JP2010276803A - Discharge element, charging device and image forming apparatus including the discharge element, and discharge element manufacturing method - Google Patents

Abstract

【Task】
Disclosed are a discharge element that can be easily recycled and reused, a charging device and an image forming apparatus including the discharge element, and a discharge element manufacturing method.
[Solution]
A support body 120 including an insulating substrate 103, a support body 120 including the common electrode 104 and the resistor 105 provided on the substrate 103, and a support body on one surface so as to be electrically connected to the common electrode 104 through the resistor 105. A plurality of discharge electrodes 101 provided by being bonded to 120, and a sheet material having insulation and flexibility, on the surface of the plurality of discharge electrodes 101 opposite to the surface to be bonded to the support 120 The discharge element 100 including the sheet material 102 that is provided by being bonded to the plurality of discharge electrodes 101 has an adhesive strength between the support 120 and each discharge electrode 101 that is smaller than the breaking strength of the sheet material 102, and The sheet material 102 and the discharge electrode 101 are configured so as to be smaller than the adhesive strength.
[Selection] Figure 4

Description

  The present invention relates to a discharge element for charging an object to be charged by a corona discharge method, a charging device and an image forming apparatus including the discharge element, and a discharge element manufacturing method.

  Conventionally, in an image forming apparatus using an electrophotographic method, a charging device that charges a photoreceptor, a transfer device that electrostatically transfers a toner image onto a recording paper, a peeling device that electrostatically peels off the recording paper, and the like, A corona discharge charging device (corona discharge device) is often used.

  As a corona discharge device, a corotron including a shield case having an opening facing a charged object such as a photosensitive member or recording paper, and a wire-like or saw-tooth-like discharge electrode provided inside the shield case is generally known. ing. The corotron uniformly charges an object to be charged by corona discharge generated when a high voltage is applied to the discharge electrode.

  As a corona discharge device, a scorotron in which a grid electrode provided between a discharge electrode and an object to be charged is added to the structure of the corotron is also known. According to the scorotron, the object to be charged can be more uniformly charged by applying a predetermined voltage to the grid electrode during corona discharge.

  As these corona discharge devices, Patent Document 1 proposes a charger in which a plurality of wedge-shaped discharge electrodes are provided and a resistor is inserted between the discharge electrodes and a power source. According to the charger described in Patent Document 1, it is said that the discharge stability and the charging uniformity can be improved. Patent Document 2 proposes a manufacturing method for easily manufacturing the charger.

  Patent Document 3 proposes a manufacturing method in which a sawtooth discharge electrode is formed by applying a circuit pattern technology of a printed wiring board.

Japanese Patent Laid-Open No. 7-5746 JP-A-8-78135 Japanese Patent Laid-Open No. 4-86877

  In the charger having a plurality of wedge-shaped discharge electrodes described in Patent Document 1 and Patent Document 2, corona discharge is generated at the tip of each discharge electrode, and therefore, a corona discharge having a wire-shaped discharge electrode in which the discharge point is not limited. There is an advantage that the amount of generated ozone is small compared to the apparatus.

  In addition, the discharge device including the sawtooth discharge electrode described in Patent Document 3 also has a wire-like discharge electrode in which the discharge point is not limited because corona discharge occurs at the tip of the protrusion of the sawtooth discharge electrode. Compared to corona discharge devices, less ozone is generated.

  On the other hand, the corona discharge device has a problem that if the discharge is continued, the discharge product adheres to the discharge electrode and the charging performance deteriorates. This problem is more conspicuous in a corona discharge device having a sawtooth or wedge-shaped discharge electrode with a limited discharge point than a corona discharge device having a wire-like discharge electrode.

  This problem will be described in more detail. FIG. 16 is a diagram for explaining a problem associated with the corona discharge device. Here, a corona discharge device including a sawtooth discharge electrode 800 that charges the photosensitive member 801 in the image forming apparatus is considered. The photoconductor 801 faces a developing roller (not shown) that carries toner. Since the developing roller rotates at a high speed, the additive released from the toner (for example, silica added externally to improve the fluidity of the toner) or the toner itself is scattered to form a floating substance 802, and the image forming apparatus Floating inside.

  As shown in FIG. 16A, these floating substances 802 are attracted to the discharge electrode 800 by corona discharge, adhere to the discharge points, and become discharge products 803. When the photoconductor 801 is charged by the corona discharge device to which the discharge product 803 is attached, the charged potential of the photoconductor 801 becomes non-uniform. That is, as shown in FIG. 16B, at the positions P1 and P2 facing the discharge point where the discharge product 803 is adhered at the longitudinal position (horizontal axis) of the photoconductor 801, the charged potential (vertical axis) is obtained. A drop occurs.

  When the photosensitive member 801 is exposed and developed in a state where the charged potential is non-uniform, the charged potential of the photosensitive member 801 falls in the formed image 804 as shown in FIG. A blank portion w corresponding to the portion is generated.

  Since such a problem is caused by corona discharge, it becomes prominent in proportion to the time of corona discharge. Therefore, the corona discharge device including a sawtooth or wedge-shaped discharge electrode has a shorter service life than a corona discharge device including a wire-like discharge electrode. Therefore, it is an issue that the corona discharge device that has passed its service life can be easily recycled and reused.

  However, in the charger described in Patent Document 1, since the wedge-shaped discharge electrodes are attached to the insulating substrate in an independent state one by one, the insulating substrate and the discharge electrode are separated and recovered. Is very difficult. In addition, since the tip of the discharge electrode has a sharp shape, there is a risk of injury by catching a finger or the like during separation work. Therefore, the charger described in Patent Document 1 cannot efficiently disassemble parts, and it is difficult to recycle and reuse the parts.

  Furthermore, when the charger is manufactured by the manufacturing method described in Patent Document 2, the inserted resistor is fixed by caulking in the mounting hole of the wedge-shaped discharge electrode. Removal is extremely difficult.

  In addition, the discharge device described in Patent Document 3 applies a circuit pattern technology of a printed wiring board, and a sawtooth discharge electrode is formed on a base material. Therefore, the base material and the discharge electrode are separated from each other. Is difficult.

Further, the corona discharge devices described in Patent Documents 1 to 3 have the following problems, respectively.
It is very difficult to manufacture a plurality of wedge-shaped discharge electrodes in the charger of Patent Document 1 with high accuracy and in large quantities so as not to cause variations in dimensions. In addition, it is a cumbersome operation to press the resistors individually without breaking them, so the productivity of the charger is very poor. Furthermore, when the resistor is mechanically press-fitted, the discharge electrode can be accidentally damaged, or the contact state of the resistor at the press-fitting part can easily vary, and the charger can be manufactured without reducing charging uniformity. It is difficult to do.

  Further, FIG. 12 of Patent Document 1 shows a method of providing a resistor without press-fitting. However, in this method, the positions of the discharge electrode and the resistor are shifted with respect to the common electrode during manufacturing. It is easy to provide the three parties with high positional accuracy. If the positions of the three members are deviated, the electric resistance value varies, and the charging uniformity is lowered.

  In the manufacturing method described in Patent Document 2, since the plurality of wedge-shaped discharge electrodes are formed by mechanically cutting the electrode connection portions, the discharge electrodes are distorted, warped, etc. due to the impact at the time of cutting. It is difficult to produce a charger without lowering the charging uniformity. Furthermore, since the number of steps involved in the manufacture of the charger is very large, it is difficult to manufacture in large quantities.

  In the discharge device described in Patent Document 3, since the sawtooth discharge electrode is formed on the insulating base material by the print pattern, the electric field at the tip of the protrusion of the discharge electrode becomes weak, and corona discharge occurs. It is difficult, and discharge uniformity will fall. That is, since one surface of the discharge electrode is in contact with the insulator, the electric field in the vicinity of the tip of the protrusion of the discharge electrode becomes weak, and corona discharge becomes unstable. This also deteriorates the charging efficiency.

  The present invention has been made to solve the above-described problems, and provides a discharge element that can be easily recycled and reused, a charging device and an image forming apparatus including the discharge element, and a discharge element manufacturing method. Objective.

The present invention provides a support including an insulating substrate, a common electrode and a resistor provided on the substrate,
A plurality of discharge electrodes provided to be bonded to the support on one surface so as to be electrically connected to the common electrode via the resistor;
A sheet material having insulation and flexibility, the sheet material provided on the surface of the plurality of discharge electrodes opposite to the surface to be bonded to the support by being bonded to the plurality of discharge electrodes. And
The discharge element characterized in that the adhesive strength between the support and the one discharge electrode is smaller than the breaking strength of the sheet material and smaller than the adhesive strength between the sheet material and the one discharge electrode. is there.

Further, the present invention has an exposed support portion that is a portion where the support is not in contact with the discharge electrode and is not covered with the sheet material,
The sheet material has an exposed sheet material portion that is a portion that is not in contact with the discharge electrode and does not cover the support.

  Further, the invention is characterized in that the sheet material has a positioning portion for determining a mounting position of the discharge element in the charging device.

In the present invention, the support comprises a plurality of partial supports adjacent to each other.
The partial support includes a partial substrate having insulating properties, a partial common electrode and a partial resistor provided on the partial substrate,
The common electrode comprises a plurality of partial common electrodes;
The resistor comprises a plurality of partial resistors,
The substrate comprises a plurality of partial substrates,
A partial common electrode connection electrode for conducting a partial common electrode provided on each of the adjacent partial supports is provided.

In the present invention, the sheet material comprises a partial sheet material provided in the same number as the one-to-one correspondence with the partial support,
The partial support is a portion that is not covered with the corresponding partial sheet material, and has a concave portion including an end of the partial support;
The partial sheet material is a portion that does not cover the corresponding partial support, and has a protruding portion that protrudes from an end of the partial support,
The convex portion of the partial sheet material corresponding to the partial support is engaged with the concave portion of the partial support adjacent to the partial support.

The present invention also provides a charging device comprising the discharge element.
The present invention also provides an image carrier that carries an electrostatic latent image;
The charging device,
The image forming apparatus is characterized in that the image carrier is charged by the charging device.

Also, the present invention provides a preparation for preparing a partial sheet material including a plurality of partial common electrodes, a partial substrate having insulation properties, and a partial support provided on the partial substrate and including the partial common electrode and the partial resistor. Process,
A portion of the partial support that is not covered by the partial sheet material, and a portion that includes the end of the partial support, and a portion of the partial sheet material that does not cover the partial support, The partial sheet material and the partial support are bonded together so that a convex portion which is a portion protruding from the end of the partial support is formed, and each partial common electrode of the partial sheet material and the partial resistance of the partial support are formed. A bonding step of forming a partial element by conducting the body;
A discharge element manufacturing method comprising a combination step of combining a plurality of partial elements by engaging a concave portion of one partial element with a convex portion of another partial element.

  According to the present invention, by pulling the sheet material, the support and the plurality of discharge electrodes can be easily separated in a short time so that the discharge electrode remains on the sheet material side while being adhered to the sheet material. Can do. Therefore, recycling of the discharge electrode is facilitated. Further, since the support is less likely to deteriorate than the discharge electrode even when used for a long time, it can be easily reused by separating the discharge electrode and the support.

  Further, according to the present invention, by supporting the exposed support portion with one hand, grasping the exposed sheet material portion with the other hand, and pulling the sheet material, the discharge electrode remains adhered to the sheet material side. Thus, it is possible to easily separate the support and the plurality of discharge electrodes in a short time. This reduces the risk of injury to the finger or the like by the tip of the discharge electrode when the separation is performed by a human hand. Accordingly, the discharge element can be reused and recycled easily and safely.

  Further, according to the present invention, the discharge element according to the present invention can be attached to the charging device with high positional accuracy using the positioning portion. Thus, the charging device can be provided so that the distance between the object to be charged and the tip of each discharge electrode is uniform. Therefore, the charging uniformity of the charging device including the discharge element according to the present invention can be improved.

  According to the present invention, since the support is composed of a partial support smaller than the support, the partial support is less likely to be damaged when the partial support and the discharge electrode are separated. Further, since the support is composed of a plurality of partial supports, the partial support and the discharge electrode can be easily separated by bending the position corresponding to the boundary between the adjacent partial supports of the sheet material. Therefore, the discharge element can be easily reused and recycled.

  Further, according to the present invention, the discharge element according to the present invention can be broken into partial elements because the partial element made of the partial support and the corresponding partial sheet material can be divided as one unit at the time of disposal. If there is no deterioration or the like, the partial element can be reused as it is.

  Further, according to the present invention, it is possible to provide a charging device that can be easily reused and recycled by including the discharge element according to the present invention.

  Further, according to the present invention, it is possible to provide an image forming apparatus that can be easily reused and recycled by including the charging device according to the present invention.

  Further, according to the present invention, a discharge element that can be easily recycled and reused can be manufactured. The discharge element manufactured according to the present invention is easily pulled in a short time so that the discharge electrode remains on the sheet material side while being adhered to the sheet material by pulling the sheet material. And can be separated. In addition, since this discharge element can be divided into a single unit when discarded, the partial element can be reused as it is if the partial element is not damaged or deteriorated.

  In addition, since this discharge element is manufactured by combining a plurality of partial elements, each member constituting the partial element is a relatively small part. Therefore, according to the manufacturing method according to the present invention, the handling property of each member at the time of manufacturing becomes high, and the management of each member becomes easy. Further, according to the manufacturing method according to the present invention, the partial elements are combined so that the convex portion and the concave portion are engaged, so that the position of the tip portion of the discharge electrode can be made uniform, and the charging of the discharge element is uniform. Sex can be maintained.

2 is a schematic view schematically showing a cross section of the image forming apparatus 1. FIG. FIG. 2 is a diagram schematically illustrating the external appearance of a charging device 12 and a photosensitive drum 11. 4 is a diagram for explaining corona discharge by the charging device 12. FIG. 1 is a perspective view showing a configuration of a discharge element 100. FIG. 5 is a diagram for explaining a manufacturing process of the discharge element 100. FIG. It is a figure for demonstrating the effect in the isolation | separation operation | work of the discharge element. 2 is a perspective view showing a configuration of a discharge element 200. FIG. 3 is a perspective view showing a configuration of a discharge element 300. FIG. 2 is a perspective view showing a configuration of a discharge element 400. FIG. 6 is a diagram for explaining a manufacturing process of the discharge element 400. FIG. 3 is a perspective view showing a configuration of a discharge element 500. FIG. 2 is a perspective view showing a configuration of a discharge element 600. FIG. 6 is a diagram for explaining a manufacturing process of the discharge element 600. FIG. 3 is an exploded perspective view of a discharge element 600. FIG. 3 is a perspective view showing a configuration of a discharge element 700. FIG. It is a figure for demonstrating the problem concerning a corona discharge device.

  An image forming apparatus according to the present invention includes an image carrier and a charging device according to the present invention. Moreover, the charging device according to the present invention includes the discharge element according to the present invention. Hereinafter, an image forming apparatus 1 that is an embodiment of the image forming apparatus according to the present invention and a charging device 12 that is an embodiment of the charging apparatus according to the present invention will be described.

  FIG. 1 is a schematic view schematically showing a cross section of the image forming apparatus 1. The image forming apparatus 1 forms a multicolor toner image by sequentially superposing four color toner images of yellow (y), magenta (m), cyan (c), and black (b). Is an electrophotographic image forming apparatus having a tandem configuration, in which an image is formed by fixing the image on a recording material. The image forming apparatus 1 includes a toner image forming unit 2, an intermediate transfer unit 3, a secondary transfer unit 4, a recording material supply unit 5, a fixing unit 6, a scanner unit 7, and a control unit unit (not shown). Including.

  The scanner unit 7 includes a document table, a light source, and a CCD (charge coupled device) sensor 9. A document to be copied is placed on the upper surface of the document table. A plate-like member made of a transparent material such as transparent glass is used for the document table. The light source illuminates the document placed on the document table. The CCD sensor 9 converts the reflected light into image information (analog signal) by photoelectrically converting the reflected light from the original illuminated by the light source.

  The CCD sensor 9 includes a conversion unit, a transfer unit, and an output unit. The conversion unit converts an optical signal that is reflected light into an electrical signal. The transfer unit sequentially transfers the electric signal to the output unit in synchronization with the clock pulse. The output unit converts the electric signal into a voltage signal, amplifies it, lowers the impedance, and outputs it.

  The control unit that controls all operations of the image forming apparatus 1 includes a control unit, a calculation unit, and a storage unit as will be described later, and performs known image processing on the analog signal obtained as described above. Convert to digital signal. The image information of the original read by the scanner unit 7 is sent to the control unit unit, subjected to various image processing, converted into a digital signal, and stored in the storage unit of the control unit unit. The image information stored in the storage unit is read from the storage unit in response to the output instruction and transferred to the optical scanning unit 13 described later.

  According to the scanner unit 7, the document placed on the document table is illuminated by the light source, and the reflected light from the illuminated document is converted into analog image information by the CCD sensor 9. The image information of the analog signal is converted into a digital signal by the control unit unit and stored in the storage unit.

  The toner image forming unit 2 includes visible image forming units 10 y, 10 m, 10 c, and 10 b and an optical scanning unit 13. The visible image forming units 10y, 10m, 10c and 10b are arranged in a line in this order from the upstream side in the rotational driving direction of the intermediate transfer belt 21, which will be described later, that is, in the direction of the arrow 27. The visible image forming units 10y, 10m, 10c, and 10b form an electrostatic latent image corresponding to image information of each color input as a digital signal, and supply toner to the electrostatic latent image to form a toner image of each color. Form.

  The visible image forming unit 10y forms a toner image corresponding to yellow (y) image information, and the visible image forming unit 10m forms a toner image corresponding to magenta (m) image information. The image forming unit 10c forms a toner image corresponding to cyan (c) image information, and the visible image forming unit 10b forms a toner image corresponding to black (b) image information. As described above, when distinguishing the visible image forming units 10y, 10m, 10c, and 10b provided according to each color for each color, an alphabet representing each color is added to the end of the reference symbol, and when collectively referred to, The reference code shall not end with an alphabet. The same applies to each member constituting the visible image forming unit 10.

  The visible image forming unit 10 includes a photoconductor drum 11, a charging device 12, a developing unit 14, a drum cleaner 15, a primary pre-charging unit 16, a primary transfer unit 22, and a photoconductor neutralizing unit 33. Including.

  The photosensitive drum 11 is a roller-like member that is supported by a driving unit (not shown) so as to be rotatable around an axis. The photosensitive drum 11 is an image carrier that includes a photosensitive layer and carries an electrostatic latent image, and thus a toner image, on the surface of the photosensitive layer.

  As the photosensitive drum 11, for example, a photosensitive substrate made of aluminum or the like and a photosensitive layer formed on the surface of the conductive substrate can be used. As the conductive substrate, a cylindrical, columnar, or sheet-shaped conductive substrate can be used, and among them, a cylindrical conductive substrate can be preferably used. Examples of the photosensitive layer include an organic photosensitive layer and an inorganic photosensitive layer.

  The organic photosensitive layer is a laminate of a charge generation layer that is a resin layer containing a charge generation material and a charge transport layer that is a resin layer containing a charge transport material, or a charge generation material and a charge in one resin layer. And a resin layer containing a transport material. Examples of the inorganic photosensitive layer include a resin layer containing one or more selected from zinc oxide, selenium, amorphous silicon and the like.

  An underlayer may be interposed between the conductive substrate and the photosensitive layer. A surface layer (protective layer) for protecting the photosensitive layer may be provided on the surface of the photosensitive layer.

  FIG. 2 is a diagram schematically showing the external appearance of the charging device 12 and the photosensitive drum 11. The charging device 12 faces the photosensitive drum 11 and is disposed along the axial direction of the photosensitive drum 11. The charging device 12 includes a discharge element 100 that is a first embodiment of the discharge element according to the present invention, a shield case 34, and a grid electrode 35.

  The discharge element 100 includes a plurality of wedge-shaped discharge electrodes 101 shown in FIG. The discharge element 100 is connected to the high voltage power source 36, and a voltage from the high voltage power source 36 is applied to the discharge electrode 101, thereby generating corona discharge at the tip of the discharge electrode 101.

  Although the polarity of the applied voltage from the high-voltage power supply 36 varies depending on the polarity of the object to be charged, the absolute value of the applied voltage is controlled within the range of 4 kV to 10 kV. Further, although the necessary applied voltage varies depending on the distance between the discharge element 100 and the other members of the charging device 12, the maximum value (absolute value) may be 10 kV or less from the viewpoint of transformer cost and safety. preferable.

  The shield case 34 is a box-shaped member having an opening in the wall facing the photosensitive drum 11. The shield case 34 has an internal space, and the discharge element 100 is provided in the internal space. The shield case 34 is disposed such that the axial direction of the photosensitive drum 11 is the longitudinal direction, and the cross-sectional shape orthogonal to the longitudinal direction is substantially U-shaped.

  The shield case 34 is grounded or connected to a power source (not shown). When connected to the power supply, a voltage having a polarity opposite to the voltage applied to the discharge electrode is applied to the shield case 34. The absolute value of this voltage is in the range of 0 kv to 1 kV.

  The grid electrode 35 is provided apart from the tip of the discharge electrode 101 within a range of 2 mm to 7 mm, for example, 4 mm apart. The grid electrode 35 has a plurality of through holes formed so as to penetrate in the thickness direction, and is connected to the bias power source 37. During the corona discharge, a voltage having a polarity opposite to the voltage applied to the discharge electrode 101 is applied from the bias power source 37 to the grid electrode 35. The absolute value of this voltage is appropriately controlled to a value necessary for image formation, and the range is 300 V to 1 kV.

  As described above, the charging device 12 generates corona discharge at the tips of the plurality of discharge electrodes 101 by the voltage applied from the high voltage power source 36. This corona discharge will be described in more detail.

  FIG. 3 is a diagram for explaining corona discharge by the charging device 12. In FIG. 3, it is assumed that the charging device 12 is a charging device that positively charges an object to be charged (photosensitive drum 11). During the corona discharge, the voltage applied to the discharge electrode 101 is controlled so that the absolute value of the total amount of current applied to all the discharge electrodes 101 is in the range of 200 μA to 1000 μA. As a result, a strong electric field is generated near the tip of the discharge electrode 101. Slight electrons (ionized by cosmic rays, etc.) that exist in nature are accelerated by this strong electric field, collide with gas molecules (oxygen molecules), and ionize oxygen atoms into electrons and cations (α action) ).

  At this time, since a positive voltage is applied to the discharge electrode 101, the cation i is accelerated in a direction away from the discharge electrode 101. When the accelerated cation i collides with another oxygen molecule, a new cation i is generated. In addition, when the cation i and the electron are recombined, other gas molecules are ionized by the emission energy generated at the time of the recombination, and a new cation i is generated. This cation i (such as a cation of oxygen that has lost electrons) moves from the discharge electrode 101 toward the photosensitive drum 11 (or the shield case 34 or the grid electrode 35), which is a charged object. The object to be charged is positively charged by the discharge current generated by the flow of ions (ion flow) toward the object to be charged.

  When the charging device 12 is a charging device that negatively charges an object to be charged, since a negative voltage is applied to the discharge electrode 101, cations collide with the discharge electrode 101 and electrons are emitted from the discharge electrode 101. (Γ action). The emitted electrons adhere to oxygen molecules in the vicinity of the discharge electrode 101, and negative ions of oxygen molecules having electrons attached to the oxygen molecules are charged from the discharge electrode 101 by the electric field in the vicinity of the discharge electrode 101. 11 (or shield case 34 or grid electrode 35). The object to be charged is negatively charged by the discharge current generated by the ion flow toward the object to be charged.

  Although the charging device 12 of the present embodiment is a scorotron including the grid electrode 35, a corotron that does not include the grid electrode 35 may be used as the charging device 12.

  The optical scanning unit 13 irradiates the charged surface of the photosensitive drums 11y, 11m, 11c, and 11b with laser beams 13y, 13m, 13c, and 13b corresponding to the image information of the respective colors, and thereby the photosensitive drums 11y and 11m. , 11c, 11b, electrostatic latent images corresponding to the image information of the respective colors are formed on the respective surfaces. A semiconductor laser or the like can be used for the optical scanning unit 13.

  The developing unit 14 includes a developing roller, a developing blade, a developing tank, and a stirring roller. The developing roller is a roller-like member that is supported by the developing tank so as to be rotatable about an axis. The developing roller is provided so that a part of the developing roller protrudes outward from an opening formed on the surface of the developing tank facing the photosensitive drum 11 and is close to the surface of the photosensitive drum 11.

  The developing roller contains a fixed magnetic pole (not shown), and the developer is carried on the surface of the developing roller by the fixed magnetic pole. The developing roller supplies the carried developer to the electrostatic latent image on the surface of the photosensitive drum 11 at a proximity portion (developing nip portion) between the developing roller and the photosensitive drum 11. The developing roller is driven to rotate in the direction opposite to that of the photosensitive drum 11. Therefore, in the developing nip portion, the surface of the developing roller and the surface of the photosensitive drum 11 move in the same direction.

  The developing roller is connected to a power source (not shown), and a DC voltage (developing voltage) is applied from the power source. As a result, the developer on the surface of the developing roller is smoothly supplied to the electrostatic latent image.

  The developing blade is a plate-like member that has one end supported by the developing tank and the other end spaced apart from the surface of the developing roller. The developing blade makes the layer thickness of the developer layer carried on the surface of the developing roller uniform.

  The developing tank is a container-like member having an internal space with an opening formed on the surface facing the photosensitive drum 11. The developing tank has a stirring roller in its internal space and stores the developer. The developer is replenished to the developing tank from a developer replenishing unit (not shown) according to the consumption state of the developer. As the developer, those commonly used in this field can be used. The developer may be a one-component developer composed only of toner or a two-component developer composed of toner and carrier.

  The agitation roller is a screw-like member that is supported so as to be rotatable about an axis in the internal space of the developing tank. The stirring roller feeds the developer in the developing tank to the periphery of the surface of the developing roller by rotational driving.

  According to the developing unit 14, the developer in the developing tank is fed to the surface of the developing roller by the stirring roller, and a developer layer is formed on the surface. The developer layer has a uniform layer thickness by a developing blade. Thereafter, a developer is selectively supplied to the electrostatic latent image on the surface of the photosensitive drum 11 by a potential difference with the photosensitive drum 11, and a toner image corresponding to the image information is formed on the surface of the photosensitive drum 11.

  The pre-primary transfer charging unit 16 is a charging device that charges a toner image formed on the surface of the photosensitive drum 11. As the pre-primary transfer charging unit 16, the same one as the charging device 12 can be used.

  The primary transfer portion 22 is a roller-like member provided so as to be rotatable around an axis by a driving unit (not shown). The primary transfer unit 22 faces the photosensitive drum 11 with the intermediate transfer belt 21 interposed therebetween, and presses the surface of the intermediate transfer belt 21 opposite to the surface in contact with the photosensitive drum 11. For the primary transfer portion 22, for example, a roller-shaped member including a metal shaft body and a conductive layer that covers the surface of the metal shaft body is used.

  The metal shaft is made of a metal such as stainless steel, for example. The conductive layer is formed of a conductive elastic body or the like. As the conductive elastic body, those commonly used in this field can be used, and examples thereof include ethylene / propylene / diene rubber (EPDM), foamed EPDM, and foamed urethane containing a conductive agent such as carbon black.

  The primary transfer unit 22 is connected to a high voltage power source (not shown). A high voltage having a polarity opposite to the charging polarity of the toner image formed on the surface of the photosensitive drum 11 is applied to the primary transfer portion 22 from a high voltage power source. As a result, the toner image formed on the surface of the photosensitive drum 11 is transferred to the surface of the intermediate transfer belt 21.

  The drum cleaner 15 removes and collects the developer remaining on the surface of the photosensitive drum 11 after the toner image on the surface of the photosensitive drum 11 is transferred to the intermediate transfer belt 21.

  The photoconductor neutralizing unit 33 neutralizes the photoconductor drum 11 after the developer is collected by the drum cleaner 15. Illumination means such as a lamp can be used for the photoreceptor charge eliminating unit 33.

  According to the toner image forming unit 2, the photosensitive drum 11 is charged by the charging device 12. The optical scanning unit 13 irradiates the charged photosensitive drum 11 with laser light corresponding to the image information of the digital signal stored in the storage unit, thereby forming an electrostatic latent image. The developing unit 14 supplies a developer to the electrostatic latent image and forms a toner image on the surface of the photosensitive drum 11. This toner image is primarily transferred to the intermediate transfer belt 21 by the primary transfer unit 22.

  The intermediate transfer unit 3 includes a transfer belt cleaner 17, a transfer belt neutralizing unit 18, an intermediate transfer belt 21, and support rollers 23, 24, and 25. The intermediate transfer belt 21 is an endless belt-like member that is stretched between support rollers 23, 24, and 25 to form a loop-shaped movement path. The intermediate transfer belt 21 rotates and moves in the direction of the arrow 27 at substantially the same peripheral speed as the photosensitive drum 11 while carrying the toner image transferred from the photosensitive drum 11. The intermediate transfer belt 21 rotates at, for example, 167 to 225 mm / s.

  For the intermediate transfer belt 21, for example, a polyimide film having a thickness of 100 μm can be used. The material of the intermediate transfer belt 21 is not limited to polyimide, and films made of synthetic resins such as polycarbonate, polyamide, polyester, and polypropylene, and various rubbers can be used. In the film made of synthetic resin or various rubbers, a conductive material such as furnace black, thermal black, channel black, and graphite carbon is blended in order to adjust the electric resistance value of the intermediate transfer belt 21.

  The support rollers 23, 24, and 25 are roller-like members that are provided so as to be rotationally driven around an axis line by a driving unit (not shown). For the support rollers 23, 24, 25, for example, an aluminum cylinder (pipe-shaped roller) is used.

  The support roller 24 is provided downstream of the photosensitive drum 11b in the rotational driving direction of the intermediate transfer belt 21. The support roller 24 is in pressure contact with a later-described secondary transfer roller 28 via the intermediate transfer belt 21 to form a secondary transfer nip portion. The support roller 24 is electrically grounded. The support roller 24 has a role of stretching the intermediate transfer belt 21 and a secondary transfer of the toner image on the intermediate transfer belt 21 onto the recording material.

  The transfer belt cleaner 17 is provided downstream of the support roller 24 in the rotational driving direction of the intermediate transfer belt 21. The transfer belt cleaner 17 is a member that removes toner remaining on the intermediate transfer belt 21 after the toner image on the intermediate transfer belt 21 is transferred to the recording material.

  The transfer belt cleaner 17 includes a cleaning blade and a toner storage container (not shown). The cleaning blade is a plate-like member that comes into pressure contact with the surface of the intermediate transfer belt 21 that carries the toner image and scrapes off residual toner and the like on the surface. For the cleaning blade, for example, an elastic rubber material (such as urethane rubber) can be used. The toner storage container is a container-like member that temporarily stores toner scraped off by the cleaning blade.

  The transfer belt neutralizing unit 18 is provided downstream of the transfer belt cleaner 17 in the rotational driving direction of the intermediate transfer belt 21 and upstream of the photosensitive drum 11y. The transfer belt neutralization unit 18 is a brush-like member that neutralizes the intermediate transfer belt 21 after the residual toner on the intermediate transfer belt 21 is removed by the transfer belt cleaner 17.

  According to the intermediate transfer unit 3, the toner images of the respective colors formed on the photosensitive drums 11y, 11m, 11c, and 11b are superposed on predetermined positions on the surface of the intermediate transfer belt 21 that carries the toner image, so that multicolor A toner image is formed. This multicolor toner image is secondarily transferred to the recording material at the secondary transfer nip portion as will be described later. After the secondary transfer, toner, offset toner, paper dust and the like remaining on the intermediate transfer belt 21 are removed by the transfer belt cleaner 17. After removal of residual toner and the like, the intermediate transfer belt 21 is neutralized by a transfer belt neutralization unit.

  The recording material supply unit 5 includes registration rollers 19 a and 19 b, a pickup roller 20, and a recording material cassette 26. The recording material cassette 26 stores the recording material 8. Examples of the recording material 8 include plain paper, coated paper, color copy dedicated paper, OHP film, and postcards. The size of the recording material 8 includes A4, A3, B5, B4, and a postcard size.

  The pickup roller 20 is a roller-like member that feeds the recording material 8 one by one to the conveyance path P. The registration rollers 19a and 19b are a pair of roller-like members provided so as to be in pressure contact with each other. The registration rollers 19a and 19b feed the recording material 8 to the secondary transfer nip portion in synchronization with the multicolor toner image on the intermediate transfer belt 21 being conveyed to the secondary transfer nip portion.

  According to the recording material supply unit 5, the recording material 8 stored in the recording material cassette 26 is fed to the conveyance path P one by one by the pickup roller 20, and further, the secondary transfer nip by the registration rollers 19 a and 19 b. Sent to the department.

  The secondary transfer unit 4 includes a pre-secondary charging unit 32 and a secondary transfer roller 28. The pre-secondary charging unit 32 is a charging device that charges the multicolor toner image carried on the intermediate transfer belt 21. As the pre-secondary charging unit 32, the same one as the charging device 12 can be used.

  The secondary transfer roller 28 is a roller-like member provided so as to be in pressure contact with the support roller 24 via the intermediate transfer belt 21. The secondary transfer roller 28 is driven to rotate around the axis by a driving unit (not shown). As the secondary transfer roller 28, for example, a roller-shaped member including a metal shaft body and a conductive layer that covers the surface of the metal shaft body is used.

  The metal shaft is made of a metal such as stainless steel, for example. The conductive layer is formed of a conductive elastic body or the like. As the conductive elastic body, those commonly used in this field can be used, and examples thereof include EPDM, foamed EPDM, foamed urethane and the like containing a conductive agent such as carbon black.

  The secondary transfer roller 28 is connected to a high voltage power source (not shown). A high voltage having a polarity opposite to the charging polarity of the multicolor toner image carried on the intermediate transfer belt 21 is applied to the secondary transfer roller 28 from a high voltage power source. As a result, the multicolor toner image carried on the intermediate transfer belt 21 is transferred to the surface of the recording material 8 at the secondary transfer nip portion.

  According to the secondary transfer unit 4, the multicolor toner image on the intermediate transfer belt 21 is secondarily transferred to the recording material 8 fed from the recording material supply unit 5. The recording material 8 carrying the unfixed multicolor toner image is conveyed to the fixing unit 6.

  The fixing unit 6 includes a paper discharge unit 29, a fixing roller 30, and a pressure roller 31. The fixing roller 30 is a roller-like member supported by a driving unit (not shown) so as to be rotatable around an axis. Heating means such as a halogen lamp is provided inside the fixing roller 30. The fixing roller 30 heats and melts the toner constituting the unfixed multicolor toner image carried on the recording material 8 to fix it on the recording material 8.

  As the fixing roller 30, for example, a roller-shaped member including a cored bar, an elastic body layer, and a surface layer can be used. As the metal forming the metal core, a metal having high thermal conductivity can be used, and examples thereof include aluminum and iron. Examples of the shape of the core metal include a cylindrical shape and a columnar shape, but a cylindrical shape with less heat radiation from the core metal is preferable.

  The material constituting the elastic layer is not particularly limited as long as it has rubber elasticity, but is preferably excellent in heat resistance. Specific examples of such materials include silicone rubber, fluorine rubber, fluorosilicone rubber, and the like. Among these, silicone rubber having particularly excellent rubber elasticity is preferable.

  The material constituting the surface layer is not particularly limited as long as it is excellent in heat resistance and durability and has low toner adsorptivity. Examples thereof include fluorine-based resin materials such as PFA (copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether) and PTFE (polytetrafluoroethylene), and fluorine rubber.

  The pressure roller 31 is a roller-like member that is rotatably provided in a state of being pressed against the fixing roller 30 below the fixing roller 30 in the vertical direction. A pressure contact portion between the fixing roller 30 and the pressure roller 31 is a fixing nip portion. The pressure roller 31 rotates following the rotational driving of the fixing roller 30. The pressure roller 31 promotes fixing of the multicolor toner image to the recording material 8 by pressing the toner in a molten state against the recording material 8 when the multicolor toner image is heated and fixed to the recording material 8. To do.

  As the pressure roller 31, for example, a roller-shaped member made of a cored bar, an elastic body layer, and a surface layer can be used. As the metal core, the elastic body layer, and the surface layer, the same metal core, elastic body layer, and surface layer as those of the fixing roller 30 can be used, respectively. In addition, similarly to the fixing roller 30, a heating unit may be provided inside the pressure roller 31.

The paper discharge unit 29 is a tray-like member that stores the recording material 8 on which the multicolor toner image is fixed.
According to the fixing unit 6, the unfixed multicolor toner image carried on the recording material 8 is heated and melted and fixed on the recording material 8. The recording material 8 on which the multicolor toner image is fixed is discharged to the paper discharge unit 29, and the image formation is completed.

  The image forming apparatus 1 includes a control unit (not shown). The control unit unit is provided, for example, at an upper part in the vertical direction in the internal space of the image forming apparatus 1 and includes a storage unit, a calculation unit, and a control unit. In the storage unit of the control unit unit, various setting values via an operation panel (not shown) arranged on the upper surface in the vertical direction of the image forming apparatus 1, detection results from sensors (not shown) arranged at various locations inside the image forming apparatus 1 Image information from an external device is input. In addition, a program for executing various processes is written. Examples of the various processes include a recording medium determination process, an adhesion amount control process, and a fixing condition control process.

As the storage unit, those commonly used in this field can be used, and examples thereof include a read only memory (ROM), a random access memory (RAM), and a hard disk drive (HDD). As the external device, an electric / electronic device capable of forming or acquiring image information and electrically connected to the image forming apparatus 1 can be used. For example, a computer, a digital camera, a television receiver, a video recorder , DVD (Digital Versatile
Disc) recorder, HDDVD (High-Definition Digital Versatile Disc) recorder, Blu-ray disc recorder, facsimile device, portable terminal device and the like.

  The calculation unit retrieves various data (image formation command, detection result, image information, etc.) written in the storage unit and various processing programs, and performs various determinations. The control unit sends a control signal to the corresponding device according to the determination result of the calculation unit, and performs operation control.

  The control unit and the calculation unit include a processing circuit realized by a microcomputer, a microprocessor or the like provided with a central processing unit (CPU). The control unit unit includes a main power source together with the processing circuit described above, and the power source supplies power not only to the control unit unit but also to each member in the image forming apparatus 1.

  Next, the discharge element 100 will be described in detail. FIG. 4 is a perspective view showing the configuration of the discharge element 100. FIG. 4A is a perspective view of the discharge element 100. FIG. 4B is a diagram in which a part of the discharge element 100 is cut away. FIG. 5 is a diagram for explaining a manufacturing process of the discharge element 100. FIG. 5A is a perspective view of the sheet electrode 110 viewed from the side where the sheet electrode 110 is bonded to the discharge electrode 101. FIG. 5B is a perspective view of the sheet electrode 110 viewed from the side not bonded to the discharge electrode 101. FIG. 5C is a perspective view of the support 120. FIG. 5D is an exploded perspective view of the discharge element 100. The discharge element 100 includes a discharge electrode 101, a sheet material 102, a substrate 103, a common electrode 104, a resistor 105, and a connection electrode 106.

  The substrate 103 is a rectangular member having insulating properties. As the substrate 103, a known substrate used for a printed wiring board (PWB) or a ceramic substrate can be used.

  A common electrode 104 and a plurality of connection electrodes 106 are provided on the substrate 103 by a method for manufacturing a printed wiring board. The common electrode 104 is formed along the longitudinal direction of the substrate 103. The plurality of connection electrodes 106 are formed in parallel along the longitudinal direction of the substrate 103.

  Further, the connection electrode 106 and the common electrode 104 are formed at a predetermined distance so that the connection electrodes 106 and the connection electrode 106 and the common electrode 104 are not short-circuited. For the common electrode 104 and the connection electrode 106, members having conductivity and corrosion resistance such as copper, SUS, and gold are used.

  A resistor 105 is provided on the substrate 103 (FIGS. 4 to 8 show the resistor in a simplified manner). The resistor 105 is a member having electrical resistance. The resistor 105 is provided such that each of the plurality of connection electrodes 106 is electrically connected to the common electrode 104 independently. As the resistor 105, a chip resistor, a sheet resistor, a printing resistor, or the like can be used. The resistor 105 may be printed on the substrate 103.

  The resistor 105 is a member for stabilizing the corona discharge by dropping the voltage applied from the high-voltage power source 36 during the corona discharge by a predetermined value. The electrical resistance value of the resistor 105 is preferably set so that the voltage drop is 200 V or more in order to stabilize corona discharge. In this embodiment, in order to satisfy this condition, the electric resistance value of the resistor 105 is set to 500 MΩ.

  A substrate in which the common electrode 104, the resistor 105, and the connection electrode 106 are provided over the substrate 103 is referred to as a support 120.

  On the connection electrode 106, the discharge electrode 101 is provided in one-to-one correspondence with the connection electrode 106. The discharge electrode 101 is provided on one surface (hereinafter referred to as “discharge electrode back surface”) by being adhered to the corresponding connection electrode 106 by a conductive adhesive member 107. As a result, the discharge electrode 101 is electrically connected to the common electrode 104 via the connection electrode 106 and the resistor 105. Further, the discharge electrodes 101 are provided so that the discharge electrodes 101, the connection electrodes 106, and the discharge electrodes 101 and the connection electrodes 106 that do not correspond to each other are not short-circuited.

In the present embodiment, a band-shaped anisotropic conductive film (ACF, Anisotropic Conductive Film) having a thickness of 35 μm is used as the adhesive member 107. Although other conductive adhesive materials can be used as the adhesive member 107, by using ACF, the discharge electrodes 101, the connection electrodes 106, and the discharge electrodes 101 and the connection electrodes 106 that do not correspond to each other are not short-circuited. Thus, it becomes easy to make the discharge electrode 101 and the corresponding connection electrode 106 conductive. In the present embodiment, the adhesion width of the discharge electrodes 101 and the connecting electrode 106, i.e., the width _{d 2} of the ACF is an adhesive member 107 is 1.5 mm.

  The discharge electrode 101 is a wedge-shaped electrode. The discharge electrode 101 is provided in the width direction of the substrate 103 such that the tip t of the discharge electrode 101 protrudes from the end of the substrate 103. In the present embodiment, the protruding amount is 2 mm. Moreover, it is preferable that the plurality of discharge electrodes 101 are provided such that the tip portions t are arranged in a substantially straight line.

  Furthermore, in this embodiment, the distance (installation pitch) between the adjacent front-end | tip parts t is 2 mm in a longitudinal direction.

  For the discharge electrode 101, a SUS material (SUS304) having a thickness of 100 μm can be suitably used. However, the present invention is not limited to this, and a metal material such as SUS430, other stainless steel materials, tungsten, or Inconel can be used. The thickness of the discharge electrode 101 is selected from a thickness of 50 μm or more and 200 μm or less as long as the sharpness of the tip portion t is maintained. The angle of the tip t of the discharge electrode 101 is preferably 15 ° or less. In the present embodiment, the width of the discharge electrode 101 is 1.4 mm.

  On the plurality of discharge electrodes 101, a sheet material 102 is adhered and provided on the surface of the discharge electrode 101 opposite to the back surface of the discharge electrode (hereinafter referred to as “discharge electrode surface”). The sheet material 102 is an insulating and flexible member and is a rectangular member extending in the longitudinal direction of the substrate 103. The sheet material 102 is provided in the width direction of the sheet material 102 so that the leading end t of the discharge electrode 101 protrudes from the end portion of the sheet material 102.

The discharge electrode 101 and the sheet material 102 are fixed with a sheet electrode adhesive. As the adhesive for the sheet electrode, a rubber-based, epoxy-based, or silicone rubber-based adhesive material can be used. In the present embodiment, a band-shaped adhesive material composed of a thermosetting resin material such as polyimide is used for the sheet electrode adhesive. This adhesive material has a configuration similar to that of the ACF, but does not need to include a conductive filler contained in the ACF. In the present embodiment, the width of the strip-shaped adhesive for sheet electrode, that is, the adhesive width d ₁ between the sheet material 102 and the discharge electrode 101 is 3 mm.

  Although the polyimide material with a thickness of 100 μm can be suitably used for the sheet material 102, the present invention is not limited to this, and engineering plastics such as polyamideimide can be used. As the sheet material 102, one having a thickness of 50 μm to 200 μm can be suitably used. Note that the breaking strength of the sheet material 102 made of polyimide is 65.2 MPa to 86.2 MPa.

  The discharge element 100 configured as described above can be manufactured by bonding the sheet electrode 110 that is the sheet material 102 provided with the discharge electrode 101 and the support 120 with the adhesive member 107.

  In this embodiment, the sheet electrode 110 is formed by metal etching on a composite member in which a stainless steel material that is a material of the discharge electrode 101 and a polyimide material that is a material of the sheet material 102 are bonded together with the above-described adhesive for the sheet electrode. And two types of etching, polyimide etching. In this forming method, first, metal etching is performed on the stainless steel material surface of the composite member. Thereby, a plurality of wedge-shaped discharge electrodes 101 are formed at a predetermined installation pitch.

  Next, the portion of the surface of the polyimide material of the composite member bonded to the tip portion t of the discharge electrode 101 and its peripheral portion are removed by polyimide etching. As a result, the leading end t of the discharge electrode 101 protrudes from the end of the sheet material 102 in the width direction of the sheet material 102.

  The chemical | medical solution used for a polyimide etching can use the polyimide etching liquid used at the time of the flying lead process of FPC (flexible printed circuit board). Further, instead of polyimide etching, laser cutting may be performed.

  As described above, in the sheet electrode 110 formed by the two types of etching, the leading end t of the discharge electrode 101 is aligned in a straight line at a predetermined installation pitch. Thereby, the charging characteristics of the charging device 12 including the discharge element 100 are improved.

  The sheet electrode 110 is not limited to the above-described forming method, and may be formed by individually bonding a plurality of previously formed discharge electrodes 101 to the sheet material 102 individually.

  Alternatively, the sheet electrode 110 may be formed by bonding a single electrode having a plurality of wedge-shaped portions to the sheet material 102 and then dividing the electrode into a plurality of discharge electrodes 101. In this way, when one electrode having a plurality of wedge-shaped portions is divided, half etching is applied to the root portions connecting the plurality of wedge-shaped portions, and the electrodes are bonded and fixed to the sheet material 102, and then the root portions are folded. It is preferable to take.

  The charging device 12 is manufactured by providing the discharge element 100 manufactured as described above in the shield case 34. The charging device 12 performs the above-described charging operation by connecting the common electrode 104 and the high-voltage power source 36.

  Moreover, since the discharge electrode 101 is formed by etching in the discharge element 100, it is possible to bend or damage the discharge electrode by mistake compared to the case where the discharge electrode 101 is formed by cutting a metal material. The nature is small. Therefore, the yield of the discharge element 100, and hence the charging device 12, is improved.

  Further, the discharge element 100 has an advantage that each member constituting the discharge element 100 can be easily reused or recycled. FIG. 6 is a diagram for explaining an advantage in the separation operation of the discharge element 100. FIG. 6A is a diagram illustrating the process of separating the discharge element 100. FIG. 6B is a diagram illustrating a state in which the sheet electrode 110 peeled off from the support 120 is rounded down. FIG. 6C is a diagram illustrating a state where the cover material 108 is pierced into the tip t of the discharge electrode 101 of the small and round sheet electrode 110. As shown in FIG. 6A, the discharge element 100 pulls the sheet electrode 110 from the support 120 by pulling the sheet material 102 in a parallel direction A that is parallel to the parallel direction of the discharge electrodes 101. be able to.

  That is, the discharge element 100 is configured such that the adhesive strength between the support 120 and each discharge electrode 101 is smaller than the adhesive strength between the sheet material 102 and the discharge electrode 101. The reason why the sheet material 102 is pulled in the parallel direction A as described above is to make the force applied to each discharge electrode 101 the same.

  Here, the adhesive strength between the support 120 and each discharge electrode 101 is configured to be smaller than the adhesive strength between the sheet material 102 and the discharge electrode 101 in the peeling test using a tensile tester. It means that the discharge element 100 is configured such that the discharge electrode 101 remains adhered to the sheet material 102 instead of the support 120. In the peeling test, for example, using a tensile testing machine such as precision universal testing machine AGS-J (Shimadzu Corporation), the support 120 is fixed at a predetermined position, and a part of the sheet material 102 is fixed to the moving head. This can be implemented by moving the moving head in the parallel direction A at a constant speed (in this embodiment, 50 mm / min).

  There are variations in the adhesive strength between the discharge electrode 101 and the support 120 and the adhesive strength between the discharge electrode 101 and the sheet material 102 for each portion of the discharge electrode 101. However, since the peeling test is performed at a constant speed, it is possible to accurately check adhesion variations.

  Thus, according to the discharge element 100 according to the present invention, the support 120 and the sheet electrode can be easily and in a short time so that the discharge electrode 101 remains adhered to the sheet material 102 after being peeled off. 110 can be separated. Therefore, since it becomes easy to separate the discharge electrode 101 and the support 120, the discharge electrode 101 can be easily recycled. Further, the support 120 is less likely to be deteriorated than the discharge electrode 101 which is deteriorated due to adhesion of discharge products due to long-term use. Therefore, the support 120 can be easily reused by removing the adhesive member 107.

In the present embodiment, in order to configure the discharge element 100 such that the adhesive strength between the support 120 and each discharge electrode 101 is smaller than the adhesive strength between the sheet material 102 and the discharge electrode 101, the adhesive member 107. ACF is used for the sheet electrode, and an adhesive material having the same structure as the ACF is used for the sheet electrode adhesive. Further, the bonding width d ₁ between the discharge electrode 101 and the sheet material 102 is 3 mm, and the bonding width d ₂ between the discharge electrode 101 and the connection electrode 106 is 1.5 mm.

Thus, in the present embodiment, the adhesive width d ₂ by smaller than the adhesive width d _1, the bonding area between the support 120- discharge electrodes 101 and smaller than the adhesive area between the discharge electrodes 101 and the sheet material 102 ing. As a result, the discharge electrode 101 remains adhered to the sheet material 102 in the peeling test.

It is not essential that the bonding width d ₁ is 3 mm and the bonding width d ₂ is 1.5 mm. If the bonding area between the support 120 and the discharge electrode 101 is smaller than the bonding area between the discharge electrode 101 and the sheet material 102. Good. For example, the adhesion area between the support 120 and the discharge electrode 101 may be less than or equal to half the adhesion area between the discharge electrode 101 and the sheet material 102. However, in order to ensure continuity the discharge electrode 101 and the connection electrode 106, the adhesion width _{d 2} is preferably at 0.5mm or more.

  In addition, by appropriately adjusting the thickness, amount, concentration, type, and adhesion conditions (heating conditions, pressure conditions, etc.) of the sheet electrode adhesive, the adhesive strength between the support 120 and each discharge electrode 101 can be reduced. The discharge element 100 may be configured to be smaller than the adhesive strength between the material 102 and the discharge electrode 101.

  Also, the sheet material 102 is pulled from the support 120 without being broken by being pulled in the parallel direction A, and after being peeled off, as shown in FIG. Plastically deforms into a new shape. That is, the discharge element 100 is configured such that the adhesive strength between the support 120 and each discharge electrode 101 is larger than the yield point strength of the sheet material 102 and smaller than the breaking strength of the sheet material 102.

  Here, the fact that the adhesive strength between the support 120 and each discharge electrode 101 is configured to be smaller than the breaking strength of the sheet material 102 means that the sheet material 102 is supported without breaking in the peeling test. It means to be peeled off from the body 120. Further, the fact that the adhesive strength between the support 120 and each discharge electrode 101 is configured to be greater than the yield point strength of the sheet material 102 means that the sheet material 102 that has been peeled off by the peeling test has a tensile strength. It means that it is plastically deformed into a small round shape by the shearing force.

  As described above, the sheet material 102 peeled off from the support 120 is plastically deformed into a small and round shape, so that the tip portions t of the plurality of discharge electrodes 101 are within a predetermined region. Therefore, even when a finger or the like touches the tip part t of the discharge electrode 101 during the separation operation, the finger or the like touches simultaneously with the plurality of tip parts t, and the contact pressure per tip part t is Get smaller. This reduces the risk of injury to fingers and the like, so that the discharge electrode 101 can be safely recycled.

  Furthermore, since the tip portions t of the plurality of discharge electrodes 101 fit within a predetermined region, as shown in FIG. 6C, the plurality of tip portions t are pierced into a cover material 108 made of rubber, polystyrene foam or the like. Can be covered. As a result, the handleability of the sheet electrode 110 after being peeled off from the support 120 is improved, so that the discharge electrode 101 can be recycled easily and safely.

  In the present embodiment, the discharge element 100 is configured such that the adhesive strength between the support 120 and each discharge electrode 101 is larger than the yield point strength of the sheet material 102 and smaller than the breaking strength of the sheet material 102. Therefore, a polyimide material having a thickness of 50 μm to 200 μm is used for the sheet material 102. When the sheet material 102 is thinner than 50 μm, the sheet material 102 is easily broken when the sheet material 102 is peeled off from the support 120. Further, when the sheet material 102 is thicker than 200 μm, there is a possibility that poor adhesion between the discharge electrode 101 and the sheet material 102 or poor adhesion and poor conduction between the discharge electrode 101 and the connection electrode 106 may occur.

  In the present embodiment, a band-shaped ACF having a thickness of 35 μm is used for the adhesive member 107. The ACF extends thinly to 10 μm or less when the ACF and the discharge electrode 101 are thermocompression bonded. The thinned ACF enters between adjacent discharge electrodes 101. As a result, the discharge electrode 101, the sheet material 102, and the adhesive member 107 are firmly fixed. Furthermore, in this embodiment, since the same kind of adhesive material as that of the adhesive member 107 is used for the adhesive for the sheet electrode, the discharge electrode 101, the sheet material 102, and the adhesive member 107 are more firmly fixed.

  Therefore, in this embodiment, when the sheet electrode 110 is peeled off from the support 120, not only the discharge electrode 101 but also the ACF as the adhesive member 107 is peeled off from the support 120 while being adhered to the sheet material 102 side. It is. Therefore, the work of removing the adhesive member 107 from the support 120 for the reuse of the support 120 as described above can be omitted.

Thus, since the discharge element 100 is easy to recycle and reuse, the charging device 12
As a result, the image forming apparatus 1 can be easily recycled and reused. In this embodiment, the charging device 12 according to the present invention is used as a charging device for charging the photosensitive drum 11. However, as other charging devices, for example, the pre-primary transfer charging unit 16 or the secondary transfer device. The charging device 12 can also be used for the pre-transfer charging unit 32.

  In addition, although the discharge electrode 100 is provided with the connection electrode 106, the common electrode 104 and the resistor 105 that conducts to the common electrode 104 are provided without providing the connection electrode 106, and the resistor 105 and the discharge electrode are provided. The resistor 105 and the discharge electrode 101 may be directly connected to each other by bonding the substrate 101 with the bonding member 107.

  Next, the discharge element 200 which is 2nd Embodiment of the discharge element which concerns on this invention is demonstrated. In each member constituting the discharge element 200, members common to the discharge element 100 are denoted by the same reference numerals, and detailed description thereof is omitted. The charging device 12 can include a discharge element 200 instead of the discharge element 100.

  FIG. 7 is a perspective view showing the configuration of the discharge element 200. FIG. 7A is a perspective view of the discharge element 200. FIG. 7B is a diagram in which a part of the discharge element 200 is cut away. The discharge element 200 includes a discharge electrode 101, a sheet material 201, a substrate 103, a common electrode 104, a resistor 105, and a connection electrode 106. The discharge element 200 includes a sheet electrode 210 that is a sheet material 201 provided with a plurality of discharge electrodes 101, and a support body 120 that is a substrate 103 provided with a common electrode 104, a resistor 105, and a connection electrode 106. It can be manufactured by bonding with the adhesive member 107 having conductivity.

  The discharge element 200 has the same configuration as the discharge element 100 except that it has an exposed sheet material portion 202 and an exposed support portion 203. That is, the sheet material 201 and the sheet electrode 210 have the same configuration as the sheet material 102 and the sheet electrode 110, respectively, except that the exposed sheet material portion 202 is included.

  Here, the exposed sheet material portion 202 is a portion of the sheet material 201 that is not in contact with the discharge electrode 101 and does not cover the support 120. More specifically, the exposed sheet material portion 202 is a part of the sheet material 201 and exists outside the end of the surface of the support 120 on the side to which the plurality of discharge electrodes 101 are bonded. This is a portion where the discharge electrode 101 is not adhered. That is, the sheet material 201 is not in contact with any member constituting the discharge element 200 in the exposed sheet material portion 202.

  The exposed support portion 203 is a portion of the support 120 that is not in contact with the discharge electrode 101 and is not covered with the sheet material 201. More specifically, the exposed support member portion 203 is a part of the support member 120, and is present outside the end of the surface of the sheet material 201 on the side to which the plurality of discharge electrodes 101 are bonded. It is a part to do. That is, the support 120 is not in contact with the discharge electrode 101, the sheet material 201, and the adhesive member 107 in the exposed support portion 203.

  As with the discharge element 100, the discharge element 200 can pull the sheet electrode 210 from the support 120 so that the discharge electrode 101 remains adhered to the sheet material 201 by pulling the sheet material 201. According to the discharge element 200, the peeling work can be easily performed by a human hand by having the exposed sheet material portion 202 and the exposed support portion 203.

  That is, by supporting the exposed support portion 203 with one hand, grasping the exposed sheet material portion 202 with the other hand, and pulling the sheet material 201 in a direction parallel to the parallel direction of the discharge electrodes 101, The support 120 can be separated. This reduces the risk of injury to the finger or the like by the tip t of the discharge electrode 101 when the separation is performed by a human hand. Therefore, the discharge element 200 can be reused and recycled easily and safely.

  In addition, the sheet material 201 is pulled from the support 120 without being broken by being pulled in a direction parallel to the parallel direction of the discharge electrodes 101, and after being peeled off, without breaking. Is plastically deformed into a small rounded shape. Therefore, the risk of injury to fingers or the like during the separation is further reduced, so that the discharge electrode 101 can be recycled more safely.

  Furthermore, since the tip portions t of the plurality of discharge electrodes 101 are within a predetermined region, the plurality of tip portions t can be covered by piercing the cover material 108.

  In the present embodiment, as in the first embodiment, when the sheet electrode 210 is peeled off from the support 120, not only the discharge electrode 101 but also the ACF as the adhesive member 107 is bonded to the sheet material 201 side. It is peeled off from the support 120 as it is. Therefore, the work of removing the adhesive member 107 from the support 120 for reuse of the support 120 can be omitted.

  Next, the discharge element 300 which is 3rd Embodiment of the discharge element which concerns on this invention is demonstrated. In each member constituting the discharge element 300, members common to the discharge elements 100 and 200 are denoted by the same reference numerals, and detailed description thereof is omitted. The charging device 12 can include a discharge element 300 instead of the discharge element 100.

  FIG. 8 is a perspective view showing the configuration of the discharge element 300. FIG. 8A is a perspective view of the discharge element 300. FIG. 8B is a diagram in which a part of the discharge element 300 is cut away. The discharge element 300 includes a discharge electrode 101, a sheet material 301, a substrate 103, a common electrode 104, a resistor 105, and a connection electrode 106. The discharge element 300 includes a sheet electrode 310 that is a sheet material 301 provided with a plurality of discharge electrodes 101, and a support body 120 that is a substrate 103 provided with a common electrode 104, a resistor 105, and a connection electrode 106. It can be manufactured by bonding with the adhesive member 107 having conductivity.

  The discharge element 300 has the same configuration as the discharge elements 100 and 200 except that it includes a positioning portion 302. That is, the sheet material 301 and the sheet electrode 310 have the same configuration as the sheet material 102 and the sheet electrode 110, respectively, except that the positioning member 302 is included.

  Here, the positioning portion 302 is a portion of the sheet material 301 and is a portion for determining the mounting position of the discharge element 300 in the charging device 12. In the present embodiment, the positioning portion 302 is provided with a long hole 302a and a round hole 302b. The long hole 302a and the round hole 302b are provided at both ends in the longitudinal direction of the sheet material 301, respectively.

  When attaching the discharge element 300 to the charging device 12, first, the discharge element 300 is temporarily fixed by inserting a screw, a boss, or the like through a hole provided in a predetermined place of the charging device 12 and the round hole 302b. To do. Next, the discharge element 300 is permanently fixed by inserting a screw, a boss, or the like through a hole provided in a predetermined place of the charging device 12 and the long hole 302a. Thus, the discharge element 300 is attached to the charging device 12 using the long hole 302a and the round hole 302b provided in the positioning portion 302. As a result, the positional accuracy of the discharge element 300 in the charging device 12 can be increased. Therefore, the charging device 12 can be provided so that the distance between the photosensitive drum 11 that is an object to be charged and the tip t of each discharge electrode 101 is uniform. Thereby, the charging uniformity of the charging device 12 can be improved.

  Moreover, since the positioning part 302 is provided in the sheet electrode 310, the positional accuracy of the sheet electrode 310 with respect to the support body 120 may be lowered. Therefore, even if the position where the sheet electrode 310 is attached to the support 120 is shifted, the charging characteristics of the charging device 12 are not impaired. Therefore, the process of attaching the sheet electrode 310 to the support 120 only needs to be attached to the support 120 so that the discharge electrode 101 and the connection electrode 106 are electrically connected. Therefore, the process is simplified. can do.

  In this embodiment, the positioning portion 302 is provided with the elongated hole 302a and the round hole 302b. However, instead of this, an engagement hole or a slit with which a positioning pin or a fixing screw is engaged may be provided.

  Similarly to the discharge element 100, the discharge element 300 can pull the sheet electrode 310 from the support 120 so that the discharge electrode 101 remains adhered to the sheet material 301 by pulling the sheet material 301. it can.

  In addition, after the sheet material 301 is pulled in the direction parallel to the parallel direction of the discharge electrodes 101, the sheet material 301 is peeled off from the support 120 without being broken, and the sheet material 301 is peeled off. Is plastically deformed into a small rounded shape. Therefore, the risk of injury to fingers or the like during the separation is further reduced, so that the discharge electrode 101 can be recycled more safely.

  Furthermore, since the tip portions t of the plurality of discharge electrodes 101 are within a predetermined region, the plurality of tip portions t can be covered by piercing the cover material 108.

  Further, in this embodiment, as in the first embodiment, when the sheet electrode 310 is peeled off from the support 120, not only the discharge electrode 101 but also the ACF as the adhesive member 107 is bonded to the sheet material 301 side. It is peeled off from the support 120 as it is. Therefore, the work of removing the adhesive member 107 from the support 120 for reuse of the support 120 can be omitted.

  Next, the discharge element 400 which is 4th Embodiment of the discharge element which concerns on this invention is demonstrated. The charging device 12 can include a discharge element 400 instead of the discharge element 100.

  FIG. 9 is a perspective view showing the configuration of the discharge element 400. FIG. 9A is a perspective view of the discharge element 400. FIG. 9B is a view in which a part of the discharge element 400 is cut away. FIG. 10 is a diagram for explaining a manufacturing process of the discharge element 400. FIG. 10A is a perspective view of the sheet electrode 410 as viewed from the side where it is bonded to the discharge electrode 401. FIG. 10B is a perspective view of the sheet electrode 410 as viewed from the side not bonded to the discharge electrode 401. FIG. 10C is a perspective view of the partial support 420. FIG. 10D is an exploded perspective view of the discharge element 400. The discharge element 400 includes a discharge electrode 401, a sheet material 402, a partial substrate 403, a partial common electrode 404, a partial resistor 405, a partial connection electrode 406, a partial common electrode connection electrode 412, and power supply. Electrode 413.

  The partial substrate 403 is a rectangular member having insulating properties. As the partial substrate 403, a known substrate used for a printed wiring board, a ceramic substrate, or the like can be used.

  A partial common electrode 404 and a plurality of partial connection electrodes 406 are provided on the partial substrate 403 by a printed wiring board manufacturing method. The partial common electrode 404 is formed along the longitudinal direction of the partial substrate 403. The plurality of partial connection electrodes 406 are formed in parallel along the longitudinal direction of the partial substrate 403.

  The partial connection electrode 406 and the partial common electrode 404 are formed at a predetermined distance so that the partial connection electrodes 406 and the partial connection electrode 406 and the partial common electrode 404 are not short-circuited. For the partial common electrode 404 and the partial connection electrode 406, members having conductivity and corrosion resistance such as copper, SUS, and gold are used.

  Further, a partial resistor 405 is provided on the partial substrate 403 (the partial resistor is simply shown in FIGS. 9 to 15). The partial resistor 405 is a member having electrical resistance. The partial resistor 405 is provided such that each of the plurality of partial connection electrodes 406 is independently connected to the partial common electrode 404. As the partial resistor 405, a chip resistor, a sheet resistor, a printed resistor, or the like can be used. The partial resistor 405 may be printed on the partial substrate 403.

  The partial resistor 405 is a member for stabilizing the corona discharge by dropping the voltage applied from the high voltage power source 36 during the corona discharge by a predetermined value. The electric resistance value of the partial resistor 405 is preferably set so that the voltage drop is 200 V or more in order to stabilize corona discharge. In this embodiment, in order to satisfy this condition, the electric resistance value of the partial resistor 405 is set to 500 MΩ.

  A substrate provided with a partial common electrode 404, a partial resistor 405, and a partial connection electrode 406 on a partial substrate 403 is referred to as a partial support 420. The partial support body 420 is used as a configuration in which a plurality of partial support bodies 420 are aligned in the same direction and combined in the longitudinal direction. This configuration is the same as that of the support 120. That is, in this embodiment, the support body 120 is composed of a plurality of partial support bodies 420 adjacent to each other. At this time, the substrate 103 includes a plurality of partial substrates 403, the common electrode 104 includes a plurality of partial common electrodes 404, the resistor 105 includes a plurality of partial resistors 405, and the connection electrode 106 includes a plurality of partial connections. It consists of an electrode 406.

  The length of the partial support 420 in the longitudinal direction is 1/2 to 1/5 of the length of the support 120 in the longitudinal direction. Therefore, when the length in the longitudinal direction of the support 120 is the maximum sheet width that can be handled by the image forming apparatus 1 (the length in the longitudinal direction of the A3 size sheet in this embodiment), the length in the longitudinal direction of the partial support 420 This is 1/2 to 1/5 of the maximum sheet width (84 mm to 210 mm in this embodiment).

  Discharge electrodes 401 are provided on the partial connection electrodes 406 in a one-to-one correspondence with the partial connection electrodes 406. The discharge electrode 401 is provided on one surface (hereinafter referred to as “discharge electrode back surface”) by being adhered to the corresponding partial connection electrode 406 by a conductive adhesive member 407. As a result, the discharge electrode 401 is electrically connected to the partial common electrode 404 via the partial connection electrode 406 and the partial resistor 405. Further, the discharge electrodes 401 are provided so that the discharge electrodes 401, the partial connection electrodes 406, and the discharge electrodes 401 and the partial connection electrodes 406 that do not correspond to each other are not short-circuited.

In the present embodiment, a band-shaped ACF having a thickness of 35 μm is used as the adhesive member 407. Although other conductive adhesive materials can be used as the adhesive member 407, by using ACF, the discharge electrodes 401, the partial connection electrodes 406, and the discharge electrodes 401 and the partial connection electrodes 406 that do not correspond to each other can be obtained. It is easy to make the discharge electrode 401 and the corresponding partial connection electrode 406 conductive so as not to be short-circuited. In the present embodiment, the adhesion width of the discharge electrode 401 and the portion connecting electrodes 406, i.e., the width _{d 4} of the ACF is an adhesive member 407 is 1.5 mm.

  A partial common electrode connection electrode 412 is provided on the two partial common electrodes 404 provided on the adjacent partial supports 420 so as to conduct the two partial common electrodes 404. The partial common electrode connection electrode 412 is provided on one surface (hereinafter referred to as “partial common electrode connection electrode back surface”) by being bonded across the two partial common electrodes 404 by a conductive adhesive member 414. It is done. For the adhesive member 414, the same kind of adhesive material as that of the adhesive member 407 can be used.

  The discharge electrode 401 is a wedge-shaped electrode. The discharge electrode 401 is provided in the width direction of the partial substrate 403 so that the tip of the discharge electrode 401 protrudes from the end of the partial substrate 403. The plurality of discharge electrodes 401 are preferably provided such that the tip portions are arranged in parallel on a substantially straight line. In the present embodiment, the installation pitch of the discharge electrodes 401 is 2 mm in the longitudinal direction.

  For the discharge electrode 401 and the partial common electrode connection electrode 412, a SUS material (SUS304) having a thickness of 100 μm can be suitably used. However, the present invention is not limited to this, and SUS430, other stainless steel materials, metal materials such as tungsten and Inconel Can be used. The thickness of the discharge electrode 401 is selected from a thickness of 50 μm or more and 200 μm or less as long as the sharpness of the tip is maintained. The thickness of the partial common electrode connection electrode 412 is set to be substantially the same as that of the discharge electrode 401. The angle of the tip of the discharge electrode 401 is preferably 15 ° or less. In the present embodiment, the width of the discharge electrode 401 is 1.4 mm.

  A sheet material 402 is provided on the plurality of discharge electrodes 401 and the plurality of partial common electrode connection electrodes 412. The sheet material 402 is a surface of the discharge electrode 401 opposite to the back surface of the discharge electrode (hereinafter referred to as “discharge electrode surface”) and a partial common electrode connection electrode back surface of the partial common electrode connection electrode 412. It is provided by adhering to the opposite surface (hereinafter referred to as “partial electrode connection electrode surface”).

  The sheet material 402 is a member having insulation and flexibility. The sheet material 402 is a rectangular member extending in the longitudinal direction of the partial substrate 403, and a rectangular notch is provided on the side where the discharge electrode 401 does not exist in the width direction of the partial substrate 403. Therefore, the sheet material 402 has a U-shaped peripheral portion of the notch. The sheet material 402 is provided in the width direction of the sheet material 402 so that the tip of the discharge electrode 401 protrudes from the end of the sheet material 402.

The discharge electrode 401, the partial common electrode connection electrode 412 and the sheet material 402 are fixed with an adhesive for sheet electrode. As the adhesive for the sheet electrode, a rubber-based, epoxy-based, or silicone rubber-based adhesive material can be used. In the present embodiment, a band-shaped adhesive material composed of a thermosetting resin material such as polyimide is used for the sheet electrode adhesive. This adhesive material has a configuration similar to that of the ACF, but does not need to include a conductive filler contained in the ACF. In the present embodiment, the discharge electrodes 401 and the width of the strip-shaped sheet electrode adhesive for bonding the sheet member 402, i.e., bonding width d ₃ of the sheet material 402 and the discharge electrode 401 is 3 mm.

  As the sheet material 402, a polyimide material having a thickness of 100 μm can be suitably used, but the invention is not limited thereto, and engineering plastics such as polyamide imide can be used. As the sheet material 402, one having a thickness of 50 μm to 200 μm can be suitably used. The breaking strength of the sheet material 402 made of polyimide is 65.2 MPa to 86.2 MPa.

  The discharge element 400 has an exposed sheet material portion 408 and an exposed support portion 409. Here, the exposed sheet material portion 408 is a portion of the sheet material 402 that is not in contact with the discharge electrode 401 and does not cover the partial support 420. More specifically, the exposed sheet material portion 408 is a part of the sheet material 402, and is more outward in the surface direction than the end of the surface of the partial support 420 on the side to which the plurality of discharge electrodes 401 are bonded. It is a part that exists and is a part to which the discharge electrode 401 is not bonded. That is, the sheet material 402 is not in contact with any member constituting the discharge element 400 in the exposed sheet material portion 408.

  The exposed support portion 409 is a portion of the partial support 420 that is not in contact with the discharge electrode 401 and is not covered with the sheet material 402. More specifically, the exposed support body portion 409 is a part of the partial support body 420, and is more outward in the surface direction than the end of the surface of the sheet material 402 on the side to which the plurality of discharge electrodes 401 are bonded. It is a part that exists. That is, the partial support 420 is not in contact with the discharge electrode 401, the sheet material 402, the adhesive member 407, the partial common electrode connection electrode 412, and the adhesive member 414 in the exposed support portion 409. In the present embodiment, a rectangular exposed support portion 409 is formed by a rectangular notch provided in the sheet material 402.

  In addition, the discharge element 400 has a positioning portion 411. Here, the positioning portion 411 is a portion of the sheet material 402 and is a portion for determining the mounting position of the discharge element 400 in the charging device 12. In the present embodiment, the positioning portion 411 is provided with a long hole 411a and a round hole 411b. The long hole 411a and the round hole 411b are provided at both ends in the longitudinal direction of the sheet material 402, respectively.

  The discharge element 400 is provided with a power supply electrode 413. The power supply electrode 413 is provided so as to adhere to the sheet material 402 on one side and to the partial common electrode 404 on the other side. The power supply electrode 413 and the sheet material 402 are fixed by a sheet electrode adhesive. The power supply electrode 413 and the partial common electrode 404 are bonded by a conductive bonding member 415. For the adhesive member 415, the same kind of adhesive material as that of the adhesive member 407 can be used.

  In the present embodiment, two power supply electrodes 413 are provided. One power supply electrode 413 is provided around the positioning portion 411 and the elongated hole 411a, and the other power supply electrode 413 is provided around the positioning portion 411 and the round hole 411b. The power supply electrode 413 may be provided only at one end of the sheet material 402.

  The discharge element 400 configured as described above includes a sheet electrode 410 that is a sheet material 402 provided with a discharge electrode 401, a partial common electrode connection electrode 412, and a power supply electrode 413, and a plurality of partial supports 420. Can be manufactured by bonding them together with adhesive members 407, 414, and 415.

  In this embodiment, the sheet electrode 410 is formed by metal etching on a composite member in which a stainless steel material that is a material of the discharge electrode 401 and a polyimide material that is a material of the sheet material 402 are bonded together with the above-described adhesive for the sheet electrode. And two types of etching, polyimide etching. In this forming method, first, metal etching is performed on the stainless steel material surface of the composite member. As a result, a plurality of wedge-shaped discharge electrodes 401 are formed at a predetermined installation pitch. As a result, a plurality of partial common electrode connection electrodes 412 and two power supply electrodes 413 are formed.

  Next, the portion bonded to the tip portion of the discharge electrode 401 and its peripheral portion on the polyimide material surface of the composite member are removed by polyimide etching. As a result, the distal end portion of the discharge electrode 401 protrudes from the end portion of the sheet material 402 in the width direction of the sheet material 402.

  As a chemical solution used for polyimide etching, a polyimide etching solution used for FPC flying lead processing can be used. Further, instead of polyimide etching, laser cutting may be performed.

  Finally, a rectangular notch, a long hole 411a, and a round hole 411b are provided in the sheet material 402 by etching or mechanical punching.

  As described above, in the sheet electrode 410 formed by the two types of etching, the front ends of the discharge electrodes 401 are aligned in a straight line at a predetermined installation pitch. As a result, the charging characteristics of the charging device 12 including the discharge element 400 are improved.

  The sheet electrode 410 is not limited to the above-described forming method, and the sheet electrode 402 includes a plurality of discharge electrodes 401, a plurality of partial common electrode connection electrodes 412, and two power supply electrodes 413 that are formed in advance. It may be formed by adhering to.

  Further, the sheet electrode 410 may be formed by bonding one electrode having a plurality of wedge-shaped portions to the sheet material 402 and then dividing the electrode into a plurality of discharge electrodes 401. As described above, when one electrode having a plurality of wedge-shaped portions is divided, half etching is performed on the root portions connecting the plurality of wedge-shaped portions, and the electrodes are bonded and fixed to the sheet material 402, and then the root portions are folded. It is preferable to take.

  The charging device 12 is manufactured by providing the discharge element 400 thus manufactured in the shield case 34. When the discharge element 400 is attached to the charging device 12, first, the discharge element 400 is temporarily fixed by inserting a screw, a boss, or the like into a hole provided in a predetermined place of the charging device 12 and a round hole 411 b. . Next, the discharge element 400 is permanently fixed by inserting a screw, a boss, or the like into a hole provided in a predetermined place of the charging device 12 and the long hole 411a. Thus, the discharge element 400 is attached to the charging device 12 using the long hole 411a and the round hole 411b provided in the positioning portion 411. Thereby, the positional accuracy of the discharge element 400 in the charging device 12 can be increased. Therefore, the charging device 12 can be provided so that the distance between the photosensitive drum 11 that is the object to be charged and the tip of each discharge electrode 401 is uniform. Therefore, the charging uniformity of the charging device 12 can be improved.

  The charging device 12 performs the above-described charging operation by connecting one of the power supply electrodes 413 and the high-voltage power source 36.

  Although the partial supports 420 each have the partial common electrode 404, all the partial common electrodes 404 are electrically connected by the partial common electrode connection electrode 412, so that the power supply electrode 413, the high voltage power source 36, As a result, the voltage can be applied to all the discharge electrodes 401. Thereby, the structure of the charging device 12 can be simplified.

  Furthermore, since the power supply electrode 413 is provided around the elongated hole 411a and the round hole 411b, the fixing for attaching the discharge element 400 to the charging device 12 and the power supply electrode 413 and the high-voltage power supply 36 are made conductive. Can be fixed at the same time. In this embodiment, the long hole 411a, the round hole 411b, and the power supply electrode 413 are provided at both ends in the longitudinal direction of the sheet material 402, but are provided in the vicinity of the partial common electrode connection electrode 412. Also good.

  In the discharge element 400, since the discharge electrode 401 and the partial resistor 405 are covered with the sheet material 402, fluctuations in the charging characteristics of the charging device 12 due to environmental changes can be suppressed. Therefore, the image forming apparatus 1 can stably form an image.

  Further, since the discharge electrode 401 is formed by etching in the discharge element 400, it is possible to bend or damage the discharge electrode by mistake compared to the case where the discharge electrode 401 is formed by cutting a metal material. The nature is small. Therefore, the yield of the discharge element 400, and hence the charging device 12, is improved.

  Moreover, since the length of the partial support body 420 in the longitudinal direction is shorter than the maximum sheet width, the partial support body 420 can be manufactured using a general board mounting facility for small components. Therefore, the capital investment is reduced, and the partial support 420, and thus the discharge element 400, can be manufactured at a low cost. On the other hand, in order to attach a resistor to a substrate whose length in the longitudinal direction is equal to or greater than the maximum paper width, a large-scale board mounting facility is required.

  For example, when a chip resistor is mounted on a known substrate used for PWB, when the wedge-shaped discharge electrode installation pitch is 2 mm and the maximum paper width is A3 size in the longitudinal direction, the longitudinal direction of the substrate Will be 30 cm or longer, and at least 150 resistors will be attached. In order to attach a large number of chip resistors to such a large-scale substrate, a large and dedicated substrate mounting facility such as a chip mounter, paste solder coating device, reflow furnace, etc. is required. The manufacturing cost will be high.

  In addition, when a ceramic substrate is used for the substrate, it is necessary to sinter and form a ceramic green sheet material (base material part). This also necessitates the manufacturing cost of the support.

  Further, since the length of the partial support 420 in the longitudinal direction is shorter than the maximum sheet width, the number of partial resistors 405 attached to one partial support 420 is relatively small. Therefore, since the probability that a defective resistor is attached on one substrate is reduced, the yield of the partial support 420 is improved.

  In addition, since the length in the longitudinal direction of the partial support 420 is shorter than the maximum paper width, even if unnecessary force is applied to the partial support 420 when handling the partial support 420, the partial support 420 is bent and bent, Less likely to warp. That is, the partial support body 420 has good handling properties. In general discharge elements, the length in the longitudinal direction of the substrate is 30 cm or more, while the length in the width direction is as short as 1 cm or less, so when fixing the discharge electrode by thermocompression bonding with ACF or the like, The substrate is likely to warp. Therefore, it is necessary to manage the temperature of the substrate in order to prevent the occurrence of warpage or the like.

  In addition, the discharge element 400 is manufactured by bonding a sheet electrode 410 in which all the discharge electrodes 401 are provided on one sheet material 402 to a plurality of combined partial supports 420. Even if there is a deviation between the combined partial supports 420, the tips of the plurality of discharge electrodes 401 are aligned in a straight line. Therefore, the charging uniformity of the charging device 12 is not impaired.

  Further, the discharge element 400 has an advantage that each member constituting the discharge element 400 can be easily reused or recycled. The discharge element 400 can peel the sheet electrode 410 from the partial support 420 by pulling the sheet material 402 in a direction parallel to the parallel direction of the discharge electrode 401. That is, the discharge element 400 is configured such that the adhesive strength between the partial support 420 and each discharge electrode 401 is smaller than the adhesive strength between the sheet material 402 and the discharge electrode 401.

  Here, the adhesive strength between the partial support 420 and each discharge electrode 401 is configured to be smaller than the adhesive strength between the sheet material 402 and the discharge electrode 401 in the peeling test using a tensile tester. This means that the discharge element 400 is configured such that the discharge electrode 401 remains adhered to the sheet material 402 instead of the partial support 420. In the peeling test, for example, a partial test body 420 is fixed at a predetermined position and a part of the sheet material 402 is fixed to the moving head by using a tensile testing machine such as precision universal testing machine AGS-J (Shimadzu Corporation). The moving head can be moved in a direction parallel to the parallel direction of the discharge electrodes 401 at a constant speed (50 mm / min in this embodiment).

  There are variations in the adhesive strength between the discharge electrode 401 and the partial support 420 and the adhesive strength between the discharge electrode 401 and the sheet material 402 for each portion of the discharge electrode 401. However, since the peeling test is performed at a constant speed, it is possible to accurately check adhesion variations.

  Further, since the discharge element 400 includes a plurality of partial support bodies 420, the sheet electrode can be easily removed from the partial support body 420 by bending the position corresponding to the boundary between the adjacent partial support bodies 420 of the discharge element 400. 410 can be peeled off. Further, since the length in the longitudinal direction of the partial support 420 is shorter than the maximum sheet width, the partial support 420 is damaged by the force applied to the partial support 420 when the sheet electrode 410 is peeled off from the partial support 420. It is rare to end up.

  As described above, according to the discharge element 400 according to the present invention, the partial support 420 and the sheet can be easily and in a short time so that the discharge electrode 401 remains adhered to the sheet material 402 after being peeled off. The electrode 410 can be separated. Further, according to the discharge element 400, the separation work can be easily performed by a human hand by having the exposed sheet material portion 408 and the exposed support portion 409. Therefore, since it becomes easy to separate the discharge electrode 401 and the partial support body 420, the discharge electrode 401 can be easily recycled. Further, the partial support 420 can be easily reused by removing the adhesive members 407, 414, and 415.

In this embodiment, in order to configure the discharge element 400 so that the adhesive strength between the partial support 420 and each discharge electrode 401 is smaller than the adhesive strength between the sheet material 402 and the discharge electrode 401, the adhesive member ACF is used for 407, and an adhesive material having the same structure as that of ACF is used for the sheet electrode adhesive. Also a bonding width _{d 3} of the discharge electrode 401 and the sheet material 402 3 mm, the adhesion width _{d 4} of the discharge electrode 401 and the portion connecting electrodes 406 and 1.5 mm.

Thus, in the present embodiment, by an adhesive width d ₄ smaller than the adhesive width d _3, the adhesion area between the partial support 420 - the discharge electrodes 401 less than the adhesion area between the discharge electrodes 401- sheet 402 is doing. As a result, the discharge electrode 401 remains adhered to the sheet material 402 in the peeling test.

It is not essential that the bonding width d ₃ is 3 mm and the bonding width d ₄ is 1.5 mm, and the bonding area between the partial support 420 and the discharge electrode 401 is smaller than the bonding area between the discharge electrode 401 and the sheet material 402. I just need it. For example, the adhesion area between the partial support 420 and the discharge electrode 401 may be equal to or less than half the adhesion area between the discharge electrode 401 and the sheet material 402. However, in order to ensure conduction between the discharge electrodes 401 and the partial connection electrode 406, it is preferred adhesion width _{d 4} is 0.5mm or more.

  In addition, by appropriately adjusting the thickness, amount, concentration, type, and bonding conditions (heating conditions, pressure conditions, etc.) of the sheet electrode adhesive, the bonding strength between the partial support 420 and each discharge electrode 401 is The discharge element 400 may be configured to be smaller than the adhesive strength between the sheet material 402 and the discharge electrode 401.

  Further, the sheet material 402 is pulled away from the partial support 420 without being broken by being pulled in a direction parallel to the parallel direction of the discharge electrode 401, and after being peeled off, the sheet material 402 has a small and round shape. Plastically deformed. That is, the discharge element 400 is configured such that the adhesive strength between the partial support 420 and each discharge electrode 401 is larger than the yield point strength of the sheet material 402 and smaller than the breaking strength of the sheet material 402. .

  Here, the fact that the adhesive strength between the partial support 420 and each discharge electrode 401 is configured to be smaller than the breaking strength of the sheet material 402 means that the sheet material 402 does not break in the peeling test. It means to be peeled off from the partial support 420. Further, the fact that the adhesive strength between the partial support 420 and each discharge electrode 401 is configured to be larger than the yield point strength of the sheet material 402 means that the sheet material 402 peeled off by the peeling test is pulled. It means that it is plastically deformed into a small round shape by the shearing force at the time.

  Thus, since the sheet material 402 peeled off from the partial support body 420 is plastically deformed into a small and rounded shape, the tips of the plurality of discharge electrodes 401 are within a predetermined region. Therefore, even when a finger or the like touches the distal end portion of the discharge electrode 401 during the separation operation, the finger or the like touches simultaneously with the plurality of distal end portions, and the contact pressure per each distal end portion is reduced. This reduces the risk of injury to fingers and the like, and the discharge electrode 401 can be safely recycled.

  Furthermore, since the tip portions of the plurality of discharge electrodes 401 are within a predetermined region, the plurality of tip portions can be covered by piercing the cover material 108. As a result, the handleability of the sheet electrode 410 after being peeled off from the partial support 420 is improved, so that the discharge electrode 401 can be recycled easily and safely.

  In this embodiment, in the discharge element 400, the adhesive strength between the partial support 420 and each discharge electrode 401 is greater than the yield point strength of the sheet material 402 and smaller than the breaking strength of the sheet material 402. In order to configure, a polyimide material having a thickness of 50 μm to 200 μm is used for the sheet material 402. When the sheet material 402 is thinner than 50 μm, the sheet material 402 is easily broken when the sheet material 402 is peeled off from the partial support body 420. Further, when the sheet material 402 is thicker than 200 μm, there is a possibility that poor adhesion between the discharge electrode 401 and the sheet material 402 or poor adhesion and poor conduction between the discharge electrode 401 and the partial connection electrode 406 may occur.

  In the present embodiment, a band-shaped ACF having a thickness of 35 μm is used for the adhesive member 407. The ACF extends thinly to 10 μm or less when the ACF and the discharge electrode 401 are thermocompression bonded. The thinned ACF enters between adjacent discharge electrodes 401. As a result, the discharge electrode 401, the sheet material 402, and the adhesive member 407 are firmly fixed. Furthermore, in this embodiment, since the same kind of adhesive material as that of the adhesive member 407 is used for the sheet electrode adhesive, the discharge electrode 401, the sheet material 402, and the adhesive member 407 are more firmly fixed.

  Therefore, in this embodiment, when the sheet electrode 410 is peeled off from the partial support 420, not only the discharge electrode 401 but also the ACF that is the adhesive member 407 is adhered to the sheet material 402 side from the partial support 420. Torn off. Therefore, the work of removing the adhesive member 407 from the partial support 420 for the reuse of the partial support 420 as described above can be omitted.

  Next, a discharge element 500 which is a fifth embodiment of the discharge element according to the present invention will be described. The charging device 12 can include a discharge element 500 instead of the discharge element 100.

  FIG. 11 is a perspective view showing the configuration of the discharge element 500. FIG. 11A is a perspective view of the discharge element 500. FIG. 11B is a diagram in which a part of the discharge element 500 is cut away. The discharge element 500 has the same configuration as the discharge element 400 except that the shape of the notch provided in the sheet material 501 and the shape of the exposed support portion 502 are different. That is, the discharge element 500 includes a discharge electrode 401, a sheet material 501, a partial substrate 403, a partial common electrode 404, a partial resistor 405, a partial connection electrode 406, a partial common electrode connection electrode 412, And a power supply electrode 413. Similarly to the discharge element 400, the discharge element 500 includes a sheet electrode 510 that is a sheet material 501 provided with a discharge electrode 401, a partial common electrode connection electrode 412, and a power supply electrode 413, and a plurality of partial supports 420. Can be manufactured by bonding them together with adhesive members 407, 414, and 415.

  The sheet material 501 has a trapezoidal shape in which the shape of the notch provided in the sheet material 501 is different from the shape of the notch provided in the sheet material 402. Therefore, the trapezoidal exposed support portion 502 is formed on the discharge element 500.

  According to the discharge element 500 according to the present invention, the partial support 420 and the sheet electrode 510 can be easily separated in a short time so that the discharge electrode 401 remains adhered to the sheet material 501. According to the discharge element 500, similarly to the discharge element 400, the separation operation can be easily performed by a human hand by having the exposed sheet material portion 408 and the exposed support body portion 502.

  Next, the discharge element 600 which is 6th Embodiment of the discharge element which concerns on this invention is demonstrated. In each member constituting the discharge element 600, members common to the discharge elements 400 and 500 are denoted by the same reference numerals, and detailed description thereof is omitted. The charging device 12 can include a discharge element 600 instead of the discharge element 100.

  FIG. 12 is a perspective view showing the configuration of the discharge element 600. FIG. 12A is a perspective view of the discharge element 600. FIG. 12B is a diagram in which a part of the discharge element 600 is cut away. FIG. 12C is a perspective view of the partial element 620. FIG. 13 is a diagram for explaining a manufacturing process of the discharge element 600. FIG. 13A is a perspective view of the partial sheet electrode 610 viewed from the side where it is bonded to the discharge electrode 401. FIG. 13B is a perspective view of the partial sheet electrode 610 viewed from the side not bonded to the discharge electrode 401. FIG. 13C is a perspective view of the partial support 420. FIG. 13D is an exploded perspective view of the partial element 620. FIG. 14 is an exploded perspective view of the discharge element 600. The discharge element 600 includes a discharge electrode 401, a partial sheet material 601, a partial substrate 403, a partial common electrode 404, a partial resistor 405, a partial connection electrode 406, and a partial common electrode connection electrode 412. .

  Also in the present embodiment, as in the fourth embodiment, a substrate in which a partial common electrode 404, a partial resistor 405, and a partial connection electrode 406 are provided on a partial substrate 403 is referred to as a partial support 420. As in the fourth embodiment, the partial support 420 is used as a configuration in which a plurality of partial supports 420 are aligned in the same direction and combined in the longitudinal direction.

  Discharge electrodes 401 are provided on the partial connection electrodes 406 in a one-to-one correspondence with the partial connection electrodes 406. The discharge electrode 401 is provided on the back surface of the discharge electrode by being adhered to the corresponding partial connection electrode 406 by a conductive adhesive member 407.

  A partial common electrode connection electrode 412 is provided on the two partial common electrodes 404 provided on the adjacent partial supports 420 so as to conduct the two partial common electrodes 404. The partial common electrode connection electrode 412 is provided on the back surface of the partial common electrode connection electrode by being bonded to one partial common electrode 404 by one adhesive member 414, and the other portion by the other adhesive member 414. It is provided by being bonded to the common electrode 404.

  One partial sheet material 601 is provided on the plurality of discharge electrodes 401 on one partial support 420 and on one partial common electrode connection electrode 412 on the partial support 420. That is, the partial sheet material 601 is provided in the same number as the partial support 420 in one-to-one correspondence with the partial support 420. The partial sheet material 601 is provided by adhering to the discharge electrode surface and the partial common electrode connection electrode surface with the above-mentioned sheet electrode adhesive.

  The partial sheet material 601 is a rectangular member extending in the longitudinal direction of the partial substrate 403. The partial sheet material 601 has a convex portion 602 that is a portion that does not cover the corresponding partial support body 420 and is a rectangular portion that protrudes from one end portion in the longitudinal direction of the partial support body 420. The portion of the partial sheet material 601 that is the convex portion 602 and the vicinity thereof and covers the corresponding partial support 420 is adhered to the surface of the partial common electrode connection electrode.

  Further, the partial sheet material 601 is provided with a notch having the same shape as the convex portion 602 at the end opposite to the end having the convex portion 602. Due to this notch, the partial support 420 is formed with a concave portion 603 that is a portion that is not covered with the corresponding partial sheet material 601 and that includes the end of the partial support 420.

  Therefore, the convex portion 602 of the partial sheet material 601 corresponding to the partial support body 420 engages with the concave portion 603 of the partial support body adjacent to the partial support body 420. The plurality of partial sheet materials 601 have the same configuration as the sheet material 402 by being combined in the longitudinal direction so that the convex portions 602 and the concave portions 603 are engaged.

  As described above, in the discharge element 600, the partial sheet material 601 is combined in the longitudinal direction and used as the same configuration as the sheet material 402, and thus can be composed of the same material as the sheet material 402. Similarly to the sheet material 402, the partial sheet material 601 is provided with a rectangular notch on the side where the discharge electrode 401 does not exist in the width direction of the partial substrate 403.

  Similarly to the discharge element 400, the discharge element 600 includes an exposed sheet material portion 604 and an exposed support body portion 605. Also in the present embodiment, similarly to the discharge element 400, the rectangular exposed support portion 605 is formed by the rectangular cutout provided in the partial sheet material 601.

  In addition, the discharge element 600 has a positioning portion 606 as with the discharge element 400. The positioning portion 606 is provided with a long hole 606a and a round hole 606b. In the present embodiment, the long hole 606 a and the round hole 606 b are provided at the end of the partial sheet material 601 on the side not bonded to the discharge electrode 401 in the width direction.

  The discharge element 600 configured as described above can be manufactured by combining a plurality of partial elements 620. The partial element 620 includes a partial sheet electrode 610 that is a partial sheet material 601 provided with the discharge electrode 401 and the partial common electrode connection electrode 412, and a partial support body 420 corresponding to the partial sheet material 601. , 414. The discharge electrode 401 and the partial common electrode connection electrode 412 provided on the partial sheet material 601 of the partial sheet electrode 610 are provided on the partial support 420 corresponding to the partial sheet material 601 in the discharge element 600. . The partial sheet electrode 610 can be manufactured by the same method as the sheet electrode 410.

  When the discharge element 600 is manufactured by combining a plurality of partial elements 620, the discharge element 600 includes a partial common electrode connection electrode 412 of one partial element 620 and a part of the other partial element 620 in the adjacent partial elements 620. The common electrode 404 is manufactured by bonding with an adhesive member 414. At this time, the partial elements 620 are combined so that the convex portion 602 and the concave portion 603 are engaged. Therefore, in the discharge element 600, since the position of the front-end | tip part of the discharge electrode 401 is aligned, the charging uniformity of the charging device 12 is not impaired. At this time, in order to combine the sub-elements 620 with higher positional accuracy, the long hole 606a and the round hole 606b can be used.

  At this time, although the partial common electrode connection electrode 412 and the partial common electrode 404 are indirectly connected by the conductive adhesive member 414, the partial common electrode connection electrode 412 and the partial common electrode 404 are connected to each other. It may be brought into contact and directly conducted. For example, a fastening screw hole is provided in the convex portion 602 of one partial element 620 and the partial substrate 403 of the other partial element 620, and the partial common electrode connection electrode 412 and the partial common electrode 404 are brought into contact with each other by pressure due to screw fastening. You may let them.

  The charging device 12 is manufactured by providing the discharge element 600 manufactured as described above in the shield case 34. When attaching the discharge element 600 to the charging device 12, first, the discharge element 600 is temporarily inserted by inserting a screw, a boss, or the like through a hole provided at a predetermined location of the charging device 12 and one round hole 606 b. Fix it. Next, the discharge element 600 is permanently fixed by inserting a screw, a boss, or the like through a hole provided at a predetermined location of the charging device 12 and the one long hole 606a. As described above, the discharge element 600 is attached to the charging device 12 using the long hole 606a and the round hole 606b provided in the positioning portion 606. Thereby, the positional accuracy of the discharge element 600 in the charging device 12 can be improved. Therefore, the charging device 12 can be provided so that the distance between the photosensitive drum 11 that is the object to be charged and the tip of each discharge electrode 401 is uniform. Therefore, the charging uniformity of the charging device 12 can be improved.

  Further, when the discharge element 600 is manufactured by combining the partial elements 620 in this way, since each member constituting the partial element 620 is a relatively small part, the handling property of each member at the time of manufacturing is high, and the management of each member is performed. Becomes easy.

  In the discharge element 600, adjacent partial common electrodes 404 are electrically connected to each other by the partial common electrode connection electrode 412. Therefore, in the discharge element 600, all the partial common electrodes 404 are conducted. As a result, it is possible to apply a voltage to all the discharge electrodes 401 simply by bringing the partial common electrode 404 and the high-voltage power supply 36 into conduction, so that the configuration of the charging device 12 can be simplified.

  Further, as described above, the partial support 420 in the discharge element 600 can be manufactured at a low cost and has a high yield. Therefore, the discharge element 600 can be manufactured at a low cost similarly to the discharge element 400.

  In addition, according to the discharge element 600 according to the present invention, as in the discharge element 400, the partial support 420 and the partial support 420 can be easily and in a short time so that the discharge electrode 401 remains adhered to the partial sheet material 601. The sheet electrode 610 can be separated. Further, according to the discharge element 600, the separation work can be easily performed by a human hand by having the exposed sheet material portion 604 and the exposed support portion 605. Therefore, since it becomes easy to separate the discharge electrode 401 and the partial support body 420, the discharge electrode 401 can be easily recycled. Further, the partial support 420 can be easily reused by removing the adhesive members 407 and 414.

  Further, since the length of the partial support 420 in the longitudinal direction is shorter than the maximum sheet width, the partial support 420 is damaged by the force applied to the partial support 420 when the partial sheet electrode 610 is peeled off from the partial support 420. It is less likely to end up.

  Further, since the discharge element 600 includes a plurality of partial support bodies 420, the partial sheet electrode can be easily removed from the partial support body 420 by bending the position corresponding to the boundary between the adjacent partial support bodies 420 of the discharge element 600. 610 can be peeled off.

  In addition, the partial sheet material 601 is pulled away from the partial support body 420 without being broken by being pulled in a direction parallel to the parallel direction of the discharge electrodes 401, without being broken. After that, it plastically deforms into a small round shape. Therefore, the risk of injury to fingers or the like during the separation is further reduced, so that the discharge electrode 401 can be recycled more safely. Furthermore, since the tip portions of the plurality of discharge electrodes 401 are within a predetermined region, the plurality of tip portions can be covered by piercing the cover material 108.

  Similarly to the discharge element 400, when the partial sheet electrode 610 is peeled from the partial support 420, the discharge element 600 adheres not only the discharge electrode 401 but also the ACF as the adhesive member 407 to the partial sheet material 601 side. As it is, it is peeled off from the partial support 420. Therefore, the work of removing the adhesive member 407 from the partial support 420 for reuse of the partial support 420 can be omitted.

  Further, since the discharge element 600 can be divided into one unit when discarded, the partial element 620 can be reused as it is when the partial element 620 is not damaged or deteriorated. .

  Next, a discharge element 700 which is a seventh embodiment of the discharge element according to the present invention will be described. The charging device 12 can include a discharge element 700 instead of the discharge element 100.

  FIG. 15 is a perspective view showing the configuration of the discharge element 700. FIG. 15A is a perspective view of the discharge element 700. FIG. 15B is a diagram in which a part of the discharge element 700 is cut away. FIG. 15C is a perspective view of the partial element 720. The discharge element 700 has the same configuration as the discharge element 600 except that it does not have the exposed support portion 605. That is, the discharge element 700 includes a discharge electrode 401, a partial sheet material 701, a partial substrate 403, a partial common electrode 404, a partial resistor 405, a partial connection electrode 406, and a partial common electrode connection electrode 412. Is provided. Similarly to the discharge element 600, the discharge element 700 is formed by bonding the partial sheet electrode 710 that is the partial sheet material 701 provided with the discharge electrode 401 and the partial common electrode connection electrode 412 and the partial support body 420 to the adhesive members 407 and 414. Can be manufactured by combining a plurality of partial elements 720 that are bonded together.

  The partial sheet material 701 has the same configuration as that of the partial sheet material 601 except that the notch provided at the end in the width direction of the partial sheet material 601 is not provided.

  According to the discharge element 700 according to the present invention, the partial support 420 and the partial sheet electrode 710 can be easily separated in a short time so that the discharge electrode 401 remains adhered to the partial sheet material 701. it can.

1 Image forming apparatus 11, 11y, 11m, 11c, 11b Photosensitive drum 12, 12y, 12m, 12c, 12b Charging device 34 Shield case 35 Grid electrode 100, 200, 300, 400, 500, 600, 700 Discharge element 101, 401 Discharge electrode 102, 201, 301, 402, 501 Sheet material 103 Substrate 104 Common electrode 105 Resistor 106 Connection electrode 107, 407, 414, 415 Adhesive member 110, 210, 310, 410, 510 Sheet electrode 120 Support body 202 , 408, 604 Exposed sheet material portion 203, 409, 502, 605 Exposed support portion 302, 411, 606 Positioning portion 302a, 411a, 606a Long hole 302b, 411b, 606b Round hole 403 Partial substrate 404 Partial common electrode 40 Partial resistor 406 parts connecting electrodes 412 parts common electrode connecting electrodes 413 power supply electrodes 420 parts support 601 and 701 parts sheet 602 convex portions 603 concave portions 610 and 710 partial sheet electrodes 620 and 720 subelement

Claims (8)

A support including an insulating substrate, and a common electrode and a resistor provided on the substrate;
A plurality of discharge electrodes provided to be bonded to the support on one surface so as to be electrically connected to the common electrode via the resistor;
A sheet material having insulation and flexibility, the sheet material provided on the surface of the plurality of discharge electrodes opposite to the surface to be bonded to the support by being bonded to the plurality of discharge electrodes. And
The discharge element, wherein an adhesive strength between the support and each discharge electrode is smaller than a breaking strength of the sheet material and smaller than an adhesive strength between the sheet material and the discharge electrode. The support is a portion not in contact with the discharge electrode, and has an exposed support portion that is a portion not covered with the sheet material,
The discharge element according to claim 1, wherein the sheet material has an exposed sheet material portion that is a portion that is not in contact with the discharge electrode and does not cover the support.   The discharge element according to claim 1, wherein the sheet material has a positioning portion for determining a mounting position of the discharge element in the charging device. The support comprises a plurality of partial supports adjacent to each other,
The partial support includes a partial substrate having insulating properties, and a partial common electrode and a partial resistor provided on the partial substrate,
The common electrode comprises a plurality of partial common electrodes,
The resistor comprises a plurality of partial resistors,
The substrate comprises a plurality of partial substrates,
The discharge element according to any one of claims 1 to 3, further comprising a partial common electrode connection electrode that conducts a partial common electrode provided on each of the adjacent partial supports. The sheet material is composed of partial sheet materials that are provided in the same number corresponding to the partial support,
The partial support is a portion that is not covered with the corresponding partial sheet material, and has a concave portion including an end portion of the partial support.
The partial sheet material is a portion that does not cover the corresponding partial support, and has a protruding portion that protrudes from an end of the partial support.
The discharge element according to claim 4, wherein a convex portion of the partial sheet material corresponding to the partial support is engaged with a concave portion of the partial support adjacent to the partial support.   A charging device comprising the discharge element according to claim 1. An image carrier for carrying an electrostatic latent image;
A charging device according to claim 6,
An image forming apparatus, wherein the image carrier is charged by the charging device. A preparation step of preparing a partial sheet material including a plurality of partial common electrodes, a partial substrate having insulation properties, and a partial support provided on the partial substrate and including the partial common electrode and the partial resistor,
A portion of the partial support that is not covered by the partial sheet material, and a portion that includes the end of the partial support, and a portion of the partial sheet material that does not cover the partial support, The partial sheet material and the partial support are bonded together so that a convex portion which is a portion protruding from the end of the partial support is formed, and each partial common electrode of the partial sheet material and the partial resistance of the partial support are formed. A bonding step of forming a partial element by conducting the body;
A discharge element manufacturing method comprising a combination step of combining a plurality of partial elements by engaging a concave portion of one partial element with a convex portion of another partial element.

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