JP2005178944A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming device capable of improving the set operation property of a recording paper sheet and visibility of the recording paper sheet. <P>SOLUTION: A manual insertion tray 32 is arranged on an upper part of a main body part 16, and the recording paper sheet is stacked on the manual insertion tray 32 in an exposed state, and thereby a number of the recording paper sheets can be easily increased or reduced compared to when the recording paper sheet is housed in a paper feeding cassette. Therefore, the set operation property of the recording paper sheet can be improved. The recording paper sheet is exposed, and thereby the visibility is improved, and the number of the recording paper sheets on the manual insertion tray 32 can be visually confirmed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus that forms an image on a recording sheet.

  Conventionally, in an image forming apparatus such as a copying machine or a printer employing an electrophotographic method, the surface of an image carrier such as a photosensitive drum is uniformly charged to a predetermined potential, and then image exposure is performed. By forming an electrostatic latent image on the surface of the image carrier and developing the electrostatic latent image with toner, the electrostatic latent image is visualized to form a toner image on the image carrier. The image is formed on the recording medium by transferring and fixing the image onto a recording medium such as paper.

For example, in Patent Document 1, as shown in FIG. 9, a sheet feeding cassette 100, a transfer device 102, and a photosensitive drum 104 are arranged so as to overlap in the vertical direction in order from the top, and a recording sheet arranged in the sheet feeding cassette 100. The main body unit 106 is reduced in size by transporting the upper part of the main body unit 106 in a substantially horizontal direction above the photosensitive drum 104, and the paper feed cassette 100 is disposed on the upper part of the main body unit 106 to supply paper. It is described that the handling operation is easy.
Japanese Patent No. 3030562

  However, since the recording sheets accommodated in the paper feeding cassette 100 can be fed only after the paper feeding cassette 100 is mounted on the main body unit 106, when the number of recording sheets in the paper feeding cassette 100 is increased or decreased, After the paper cassette 100 is removed from the main body 106, the number of recording sheets is increased and decreased, and the paper feed cassette 100 must be mounted on the main body 106 again.

  Further, the upper surface of the paper feed cassette 100 is often covered with a cover, and it is difficult to check the number of recording sheets in the paper feed cassette 100. Further, when the upper surface of the paper feed cassette 100 is covered with a cover, when setting a small size recording sheet, the cover becomes an obstacle and it is difficult to place the paper cassette 100 in the back of the paper feed cassette 100. .

  In consideration of the above facts, an object of the present invention is to provide an image forming apparatus having good recording sheet setting operability and good recording sheet visibility.

  According to the first aspect of the present invention, in the image forming apparatus, a manual feed tray disposed on an upper part of a main body provided with a recording unit for forming an image and placed with the recording sheet exposed, and the manual feed tray A U-turn conveyance path in which a recording sheet placed on the U-turns above the recording means, an image is formed by the recording means, and is discharged to a discharge tray disposed substantially parallel to the manual feed tray; It is characterized by having.

  According to the first aspect of the present invention, the manual feed tray placed with the recording sheet exposed is arranged on the upper part of the main body provided with the recording means for forming an image, and placed on the manual feed tray. The recording sheet is U-turned above the recording means by the U-turn conveyance path, an image is formed by the recording means, and is discharged to a discharge tray disposed substantially parallel to the manual feed tray.

  Here, the manual feed tray is arranged on the upper part of the main body, and the recording sheet is placed on the manual feed tray in an exposed state, so that the recording sheet is stored in the paper feeding cassette as compared with the case where the recording sheet is accommodated. Since the number of sheets can be easily increased or decreased, the recording sheet setting operability is good. Also, since the recording sheet is exposed, the visibility is good, for example, the number of recording sheets on the manual feed tray can be visually confirmed.

  In particular, in the case of a small size recording sheet, it is troublesome to place the small size recording sheet in the back of the paper feed cassette because the cover constituting the paper feeding cassette is in the way, but with the recording sheet exposed Since it is placed on the manual feed tray, the operability for setting a small-sized recording sheet is remarkably improved.

  On the other hand, it is possible to place the discharge tray below the manual feed tray by making a U-turn on the recording sheet conveyed by the U-turn conveyance path. Accordingly, the projection area of the image forming apparatus can be reduced as compared with the case where the discharge tray is disposed on the opposite side of the manual feed tray.

  In addition, since the U-turn conveyance path causes the recording sheet to be conveyed to be U-turned, the setting operation of the recording sheet to the manual feed tray and the operation of taking out the recording sheet from the discharge tray can be performed from the same direction. The operator's operation becomes easier and the operability can be improved without increasing the installation area of the image forming apparatus.

  In addition, the recording sheet can be set to the manual feed tray and the recording sheet can be removed from the discharge tray from the same direction, so the main body of the image forming apparatus can be installed near the wall, saving space. Can contribute.

  According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the recording unit transfers an image carrier carrying toner and a toner image formed on the image carrier to a recording sheet. And a fixing unit that fixes the toner image transferred to the recording sheet.

  According to the second aspect of the present invention, the recording unit is applied to a xerographic image forming apparatus including an image carrier, a transfer unit, and a fixing unit, whereby the effect according to the first aspect is provided. Can be obtained more effectively.

  According to a third aspect of the present invention, in the image forming apparatus according to the second aspect, the image carrier is disposed below the transfer unit.

  In the invention described in claim 3, by disposing the image carrier below the transfer means, the recording surface of the recording sheet becomes the lower surface side, and in this state, the recording sheet is discharged to the discharge tray. The recording sheets on the discharge tray are stacked on the top in the order in which the images are formed. For this reason, there is no need to rearrange the recording sheets discharged to the discharge unit in the page order.

  In addition, since the recording surface of the recording sheet is below the U-turn conveyance path for conveying the recording sheet, it is possible to reduce the possibility that the recording sheet being conveyed is contaminated with floating toner.

  According to a fourth aspect of the present invention, in the image forming apparatus according to any one of the first to third aspects, the manual feed tray is detachably provided, and a mounting surface from which the manual feed tray is removed is substantially horizontal. It is a feature.

  In the invention according to claim 4, the manual feed tray is detachably provided, and the mounting surface from which the manual tray is removed is made substantially horizontal so that the image reading device or the like can be placed on the mounting surface. It is possible to provide an excellent image forming apparatus.

  According to a fifth aspect of the present invention, in the image forming apparatus according to the fourth aspect, a recording sheet insertion port for feeding a recording sheet to the transfer means is provided on a side surface of the main body.

  In the invention described in claim 5, the recording sheet insertion port for sending the recording sheet to the transfer means is provided on the side surface of the main body so that the recording sheet can be conveyed substantially linearly from the recording sheet insertion port to the transfer means. It becomes possible. Thereby, even a recording sheet such as cardboard can be conveyed.

  According to a sixth aspect of the present invention, in the image forming apparatus according to the fifth aspect, the main body is stacked on the mounting surface.

  According to the sixth aspect of the present invention, by stacking the main body on the mounting surface, a plurality of recording units are provided in one image forming apparatus, and it is possible to provide an image forming apparatus excellent in expandability. it can.

  According to a seventh aspect of the present invention, in the image forming apparatus according to any one of the first to sixth aspects, a sheet cassette disposed in a lower portion of the main body so as to be expandable and capable of storing a recording sheet, and the sheet cassette And a sheet conveying path that rises in a substantially vertical direction and guides to the transfer means.

  According to the seventh aspect of the present invention, a sheet cassette can be added to the lower part of the main body so that an image forming apparatus with high expandability can be provided by attaching each sheet cassette according to the size of the recording sheet. can do. Further, the projected area of the image forming apparatus can be reduced by raising the sheet conveyance path from the sheet cassette in a substantially vertical direction and guiding it to the transfer unit.

  According to an eighth aspect of the present invention, in the image forming apparatus according to the seventh aspect, a sheet reversing unit that reversely conveys the recording sheet discharged to the discharge tray in a direction opposite to the discharge direction, and disposed at a lower portion of the main body portion. And a return conveyance path for returning the reversely conveyed recording sheet to the sheet conveyance path.

  According to the eighth aspect of the invention, the recording sheet discharged to the discharge tray is reversely conveyed in the direction opposite to the discharge direction and returned to the sheet conveyance path, thereby enabling duplex printing. Thus, by providing a return conveyance path (so-called double-sided unit) for duplex printing at the bottom of the main body, there is no effect on the operability of the manual feed tray disposed at the top of the main body. Double-sided units can be added.

  According to a ninth aspect of the present invention, in the image forming apparatus according to the eighth aspect, a cover body that covers an upper portion of the sheet cassette constitutes at least a part of the return conveyance path.

  According to the ninth aspect of the present invention, the cover body that covers the upper portion of the sheet cassette also serves as at least a part of the return conveyance path, whereby the height of the image forming apparatus can be suppressed when the duplex unit is added.

  According to a tenth aspect of the present invention, in an image forming apparatus, an image carrier that carries toner, a transfer unit that transfers a toner image formed on the image carrier to a recording sheet, and the image that is transferred to the recording sheet. A fixing unit that fixes the toner image; a manual feed tray that is placed on the upper portion of the main body portion where the recording means for forming an image is provided; and is placed on the side surface of the main body portion. A recording sheet insertion port for sending a recording sheet to the transfer unit; and a sheet cassette which is disposed at a lower portion of the main body and can store the recording sheet. The manual feed tray and the sheet insertion port are located upstream of the transfer unit. And a merging unit capable of merging the recording sheets supplied from the sheet cassette is provided.

  In the invention according to the tenth aspect, even if various paper feeding units are added by providing a merging section for merging the recording sheets supplied from the manual feed tray, the sheet insertion slot and the sheet cassette upstream of the transfer means. The recording sheet conveyed from the paper unit always passes through the junction.

  For this reason, the configuration of the image forming unit located on the downstream side of the merging unit is not affected. In other words, even if the various paper feeding units are added, the configuration of the image forming unit is not affected, so that the various paper feeding units can be easily added.

  According to an eleventh aspect of the present invention, in the image forming apparatus according to the tenth aspect, the manual feed tray and the sheet cassette are detachably provided, and the attachment surface from which the manual feed tray and the sheet cassette are removed is substantially horizontal. It is characterized by being.

  In the invention described in claim 11, the manual feed tray and the sheet cassette are detachably provided, and the mounting surface from which the manual feed tray and the sheet cassette are removed is substantially horizontal, so that the stability of the image forming unit is improved, and the main body Even when the main body portions are stacked in multiple stages on the upper and lower portions of the portion, they can be stacked in a stable state.

  According to a twelfth aspect of the present invention, in the image forming apparatus according to the tenth or eleventh aspect, a lid that can open and close the inside of the main body is provided, and the manual feed tray, the transfer unit, and the fixing unit are A process cartridge which is fixed to the lid and is disposed inside and stores the image carrier is detachably provided.

  In the twelfth aspect of the invention, by fixing the manual feed tray, transfer means, and fixing means to the lid, the manual feed tray, transfer means, and fixing means move together with the lid when the lid is opened and closed. Will be. For this reason, the transfer unit and the fixing unit can be retracted from the mounting / demounting space of the process cartridge, and when replacing the process cartridge, there is no risk of touching the high temperature part by mistake, and the operability is improved.

  Here, by removing the process cartridge toward the manual feed tray and the discharge tray, the operator can perform various operations at the same standing position, so that the operation becomes easy and the work efficiency can be improved.

  Since the present invention is configured as described above, in the invention described in claim 1, the manual feed tray is arranged on the upper part of the main body, and the recording sheet is placed on the manual feed tray in an exposed state, so that the inside of the paper feed cassette is provided. Compared with the case where recording sheets are accommodated, the number of recording sheets can be easily increased or decreased, so that the recording sheet setting operability is good. Also, since the recording sheet is exposed, the visibility is good, for example, the number of recording sheets on the manual feed tray can be visually confirmed.

  On the other hand, it is possible to place the discharge tray below the manual feed tray by making a U-turn on the recording sheet conveyed by the U-turn conveyance path. Accordingly, the projection area of the image forming apparatus can be reduced as compared with the case where the discharge tray is disposed on the opposite side of the manual feed tray. In addition, since the U-turn conveyance path causes the recording sheet to be conveyed to be U-turned, the setting operation of the recording sheet to the manual feed tray and the operation of taking out the recording sheet from the discharge tray can be performed from the same direction. The operator's operation becomes easier and the operability can be improved without increasing the installation area of the image forming apparatus. In addition, the recording sheet can be set to the manual feed tray and the recording sheet can be removed from the discharge tray from the same direction, so the main body of the image forming apparatus can be installed near the wall, saving space. Can contribute.

  According to the second aspect of the present invention, the effect described in the first aspect can be obtained more effectively by being applied to an xerographic image forming apparatus.

  In the invention described in claim 3, by disposing the image carrier below the transfer means, the recording surface of the recording sheet becomes the lower surface side, and in this state, the recording sheet is discharged to the discharge tray. The recording sheets on the discharge tray are stacked on the top in the order in which the images are formed. For this reason, there is no need to rearrange the recording sheets discharged to the discharge unit in the page order. In addition, since the recording surface of the recording sheet is below the U-turn conveyance path for conveying the recording sheet, it is possible to reduce the possibility that the recording sheet being conveyed is contaminated with floating toner.

  In the invention according to claim 4, the manual feed tray is detachably provided, and the mounting surface from which the manual tray is removed is made substantially horizontal so that the image reading device or the like can be placed on the mounting surface. It is possible to provide an excellent image forming apparatus.

  In the invention according to claim 5, by providing the recording sheet insertion port for sending the recording sheet to the transfer means on the side of the main body, it becomes possible to linearly convey the recording sheet from the recording sheet insertion port to the transfer means, Thereby, even a recording sheet such as cardboard can be conveyed.

  According to the sixth aspect of the present invention, it is possible to provide an image forming apparatus excellent in expandability by stacking the main body on the mounting surface.

  According to the seventh aspect of the present invention, it is possible to provide a highly expandable image forming apparatus by providing an additional sheet cassette at the lower part of the main body. Further, the projected area of the image forming apparatus can be reduced by raising the sheet conveyance path from the sheet cassette in a substantially vertical direction and guiding it to the transfer unit.

  According to the eighth aspect of the invention, the recording sheet discharged to the discharge tray is reversely conveyed in the direction opposite to the discharge direction and returned to the sheet conveyance path, thereby enabling duplex printing. In this way, by providing a return conveyance path for duplex printing at the lower part of the main body, it is possible to add a double-sided unit without affecting the operability of the manual feed tray disposed at the upper part of the main body.

  According to the ninth aspect of the present invention, the cover body that covers the upper portion of the sheet cassette also serves as at least a part of the return conveyance path, whereby the height of the image forming apparatus can be suppressed when the duplex unit is added.

  In the invention according to the tenth aspect, even if various paper feeding units are added by providing a merging section for merging the recording sheets supplied from the manual feed tray, the sheet insertion slot and the sheet cassette upstream of the transfer means. Since the recording sheet conveyed from the paper unit always passes through the merging unit, the configuration of the image forming unit located on the downstream side of the merging unit is not affected. In other words, even if the various paper feeding units are added, the configuration of the image forming unit is not affected, so that the various paper feeding units can be easily added.

  In the invention described in claim 11, the manual feed tray and the sheet cassette are detachably provided, and the mounting surface from which the manual feed tray and the sheet cassette are removed is substantially horizontal, so that the stability of the image forming unit is improved, and the main body Even when the main body portions are stacked in multiple stages on the upper and lower portions of the portion, they can be stacked in a stable state.

  In the twelfth aspect of the invention, by fixing the manual feed tray, transfer means, and fixing means to the lid, the manual feed tray, transfer means, and fixing means move together with the lid when the lid is opened and closed. Therefore, the transfer unit and the fixing unit can be retracted from the space where the process cartridge is attached / detached, and when replacing the process cartridge, there is no risk of touching the high temperature part by mistake, and the operability is improved. .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 and 2, the image forming apparatus 10 according to the embodiment of the present invention includes a main body portion 16 provided with an image forming portion 14 including a photosensitive drum 12 that carries toner. Is provided. The main body 16 has a substantially rectangular parallelepiped shape, and has an upper surface and a lower surface that are formed substantially horizontally (described later).

  An optical scanning device 18 is disposed at the bottom of the main body 16, and laser light emitted from a semiconductor laser (not shown) is polygon mirror 20 based on image data read by an image reading device (not shown). Is deflected and scanned. The laser beam deflected and scanned by the polygon mirror 20 is bent on the optical path by the mirror 22 through the fθ lens 21 and projected onto the peripheral surface of the photosensitive drum 12 to which the surface has been charged in advance by the charging roll 24, and is photosensitive. An electrostatic latent image is formed on the peripheral surface of the body drum 12.

  Here, the charging roll 24 and the photosensitive drum 12 are rotatably disposed on the process cartridge 26, and can be attached to and detached from the main body 16 integrally with the process cartridge 26. The process cartridge 26 is provided with a developing device 28 in addition to the charging roll 24 and the photosensitive drum 12, and the electrostatic latent image formed on the photosensitive drum 12 by the developing device 28 is used as a toner image. Developed.

  A transfer roll 38 is rotatably disposed above the photosensitive drum 12, and a transfer bias power source (not shown) is connected to the transfer roll 38, and a transfer bias having a polarity opposite to a predetermined toner polarity is predetermined. It is applied at the timing. When the recording sheet P passes between the transfer roll 38 and the photosensitive drum 12, a toner image is transferred to the lower surface of the recording sheet P.

  Further, a fixing device 40 is disposed on the downstream side of the photoconductive drum 12. After fixing processing is performed by applying heat and pressure to the recording sheet P onto which the toner image has been transferred, downstream of the fixing device 40. The recording sheet P is guided to the discharge roll 42 disposed on the side.

  On the other hand, a discharge tray 44 is provided below the side surface 16 </ b> A located on the discharge roll 42 side of the main body 16, and the recording sheet P guided to the discharge roll 42 is discharged to the discharge tray 44. ing.

  Incidentally, a horizontal attachment surface 30 is formed on the upper surface of the main body portion 16. A manual feed tray 32 is placed on the attachment surface 30 and is detachably attached to the main body portion 16. An opening (not shown) is formed in a part of the attachment surface 30, and the recording sheet P supplied from the manual feed tray 32 is guided into the main body 16 through the opening.

  Here, the manual feed tray 32 is provided with a placement table 34 having a substantially U-shaped cross section, and the recording sheet P in the manual feed tray 32 is placed on the placement table 34 in an exposed state. It becomes.

  Further, a U-turn conveyance path 36 that guides the recording sheet P supplied from the manual feed tray 32 to the image forming unit 14 is provided from the manual feed tray 32 to the inside of the main body 16. The U-turn conveyance path 36 is substantially U-shaped when viewed from the front, and the conveyance direction of the recording sheet P conveyed on the mounting table 34 of the manual feed tray 32 and the recording sheet P passing through the photosensitive drum 12. The transport direction is reversed.

  In this way, by the U-turn conveyance path 36, the conveyance direction of the recording sheet P conveyed on the mounting table 34 of the manual feed tray 32 and the conveyance direction of the recording sheet passing through the photosensitive drum 12 are reversed. The discharge tray 44 can be disposed below the mounting table 34 of the manual feed tray 32.

  As shown in FIG. 4, the upper portion of the main body portion 16 is a lid body 46, which is pivotally supported with respect to the main body portion 16 so that the inside of the main body portion 16 can be opened and closed. The manual feed tray 32 is fixed to the upper surface of the lid 46, and the fixing device 40 and the transfer roll 38 are fixed to the rear surface of the lid 46. For this reason, when the lid 46 is opened and closed, the manual feed tray 32, the fixing device 40 and the transfer roll 38 move together with the lid 46.

  Further, as shown in FIG. 1, a recording sheet insertion port 48 through which a recording sheet can be supplied is provided on the side surface 16B facing the side surface 16A of the main body 16 provided with the discharge tray 44. On the other hand, a merging portion 50 is provided on the upstream side of the pair of registration rolls 49 located on the upstream side of the photosensitive drum 12 in the U-turn conveyance path 36, and the recording sheet supplied from the recording sheet insertion port 48 is merged. The portion 50 joins the U-turn conveyance path 36 and is guided to the image forming portion 14 by the resist roll pair 49.

  Further, a horizontal attachment surface 72 is formed at the lower part of the main body 16, and the sheet feeding cassette unit 52 having a substantially L-shaped cross section can be attached and detached with a gap 73 between the attachment surface 72. Is attached. The paper feed cassette unit 52 includes a paper feed unit 54 provided horizontally and a transport unit 56 provided perpendicular to the paper feed unit 54.

  A paper feed cassette 55 is accommodated in the paper feed unit 54 and is detachable. A pressing plate 55A is provided at the bottom of the paper feed cassette 55 so as to be swingable upward, and the recording sheet accommodated in the paper feed cassette 55 is pivotally supported by the paper feed unit 54. The recording sheet is pressed against the feed roll 58 for separating and conveying the recording sheet.

  As a result, the recording sheets to be supplied to the transport unit 56 are fed one by one, and the registration roll 60A rotatably supported by the paper feed unit 54 and the registration roll 60B rotatably supported by the paper feed cassette 55 are provided. It is guided to a resist roll pair 60 constituted by

  On the other hand, the conveyance unit 56 is provided with a sheet conveyance path 62 that raises the recording sheet guided from the resist roll pair 60 substantially vertically and guides it to the merging unit 50 in the main body unit 16. The recording sheet conveyed at 62 is merged into the U-turn conveyance path 36 through the merge unit 50 and is guided to the image forming unit 14 by the resist roll pair 49.

  By the way, as shown in FIGS. 2 and 3, a return conveyance unit 64 can be attached to a gap 73 provided between the paper feed cassette unit 52 and the attachment surface 72 as an option. When the return conveyance unit 64 is attached, the discharge tray 44 is attached to the side surface of the return conveyance unit 64.

  Further, the reverse conveyance unit 64 is provided with a reverse conveyance unit 66 so that a recording sheet on which an image is formed and discharged onto the discharge tray 44 can be reversely conveyed. In this way, the recording sheet that has been reversed and conveyed is guided to the return conveyance path 68 positioned below the main body 16.

  The return conveyance path 68 and the conveyance unit 56 of the paper feed cassette unit 52 can communicate with each other, and the conveyance unit 56 is provided with a merging conveyance path 70 that bridges the return conveyance path 68 and the sheet conveyance path 62. ing.

  For this reason, the recording sheet conveyed from the return conveyance path 68 is guided to the sheet conveyance path 62 through the merging conveyance path 70, and merged to the U-turn conveyance path 36 at the merging unit 50, and the surface on which the image has already been formed. Then, it is guided again to the image forming unit 14 by the resist roll pair 49, and is discharged to the discharge tray 44 in a state where both sides are printed.

  The operation of the image forming apparatus according to the embodiment of the present invention will be described.

  As shown in FIGS. 1 and 3, a manual feed tray 32 is disposed on the upper portion of the main body 16, and the manual feed tray 32 is provided with a mounting table 34 having a substantially U-shaped cross section, and recording in the manual feed tray 32 is performed. The sheet P is placed on the placement table 34 in an exposed state.

  As a result, as shown in FIG. 9, the number of recording sheets can be easily increased / decreased as compared with the case where recording sheets are stored in the paper feed cassette 100, so that the recording sheet setting operability is good. Become.

  In particular, in the case of a small size recording sheet, the cover constituting the paper feed cassette 100 becomes an obstacle, and it is troublesome to arrange the small size recording sheet in the back of the paper feed cassette 100, but FIGS. As shown in FIG. 5, since the recording sheet P is placed on the manual feed tray 32 in an exposed state, the setting operability of the small-sized recording sheet P is remarkably improved. Further, since the recording sheet P is exposed, the visibility is good because the number of recording sheets P on the manual feed tray 32 can be visually confirmed.

  On the other hand, a U-turn conveyance path 36 that guides the recording sheet P supplied from the manual feed tray 32 to the image forming unit 14 is provided from the manual feed tray 32 to the inside of the main body 16. The U-turn conveyance path 36 makes the U-turn of the recording sheet P to be conveyed, so that the discharge tray 44 can be disposed below the manual feed tray 32. As a result, the projection area of the image forming apparatus 10 can be reduced as compared with the case where the discharge tray 44 is disposed on the opposite side of the manual feed tray 32.

  Further, the recording sheet P to be conveyed is U-turned by the U-turn conveyance path 36, whereby the setting operation of the recording sheet P to the manual feed tray 32 and the operation of taking out the recording sheet P from the discharge tray 44 are performed from the same direction. Therefore, the operation of the operator is facilitated and the operability can be improved without increasing the installation area of the image forming apparatus 10.

  Further, since the setting operation of the recording sheet P to the manual feed tray 32 and the operation of taking out the recording sheet P from the discharge tray 44 can be performed from the same direction, the main body portion 16 of the image forming apparatus 10 is installed near the wall. Can contribute to space saving.

  Here, a transfer roll 38 is disposed above the photosensitive drum 12. As described above, by disposing the transfer roll 38 on the upper portion of the photosensitive drum 12, the recording surface of the recording sheet P becomes the lower surface side, and in this state, the recording sheet P is discharged to the discharge tray 44. The recording sheets on the discharge tray 44 are stacked on the top in the order in which the images are formed. For this reason, it is not necessary to rearrange the recording sheets P discharged to the discharge tray 44 in the page order. Further, since the recording surface of the recording sheet P is below the U-turn conveyance path 36 that conveys the recording sheet P, the possibility that the recording sheet P being conveyed is contaminated with floating toner can be reduced.

  Further, the main body portion 16 has a substantially rectangular parallelepiped shape, and substantially horizontal mounting surfaces 30 and 72 are formed on the upper and lower surfaces of the main body portion 16. As described above, by forming the upper surface and the lower surface of the main body 16 substantially horizontally, the stability of the image forming unit 14 can be improved.

  Further, the manual feed tray 32 or the paper feed cassette unit 52 is detachably provided on the horizontal attachment surfaces 30 and 72. Accordingly, another device or the like may be placed on the trace from which the manual feed tray 32 or the paper feed cassette unit 52 has been removed, and an image forming apparatus with excellent expandability can be provided.

  Specifically, as shown in FIG. 5, an image reading device 74 may be placed on the attachment surface 30. Further, as shown in FIGS. 1 and 3, in the paper feed cassette unit 52, the return transport unit 64 can be attached and detached, but as shown in FIG. 5, the paper feed cassette unit 75 to which the return transport unit 64 cannot be attached. May be used. In this case, since it is not necessary to provide a gap between the paper feed cassette unit 75 and the mounting surface 72, the height of the paper feed cassette unit 75 can be reduced accordingly.

  Further, as shown in FIG. 6, the main body 16 may be stacked. The mounting surfaces 30 and 72 from which the manual feed tray 32 and the paper feed cassette unit 52 are removed are made substantially horizontal, so that the main body 16 can be stacked and used in multiple stages on the upper and lower portions of the main body 16, respectively. Can be stacked.

  As described above, when stacking the main body parts 16, even if there is a conveyance path that is not used, there is no problem in the conveyance property of the recording sheet. Costs may be reduced.

  Here, as shown in FIG. 3, at the upstream of the transfer roll 38, a joining unit 50 that joins the recording sheets supplied from the manual feed tray 32, the recording sheet insertion port 48, the paper feed cassette unit 52, and the return conveyance unit 64 is provided. Provided.

  For this reason, even if various sheet feeding units such as the manual feed tray 32, the recording sheet insertion port 48, the sheet feeding cassette unit 52, and the return conveying unit 64 are added, the recording sheet conveyed from the sheet feeding unit is always the joining section 50. Will pass.

  Therefore, the configuration of the image forming unit 14 located on the downstream side of the merging unit 50 is not affected. In other words, even if the various paper feeding units are added, the configuration of the image forming unit 14 is not affected, so that the various paper feeding units can be easily added.

  Further, as shown in FIG. 4, a fixing device 40 and a transfer roll 38 are fixed to the back surface of a lid body 46 that opens and closes the inside of the main body portion 16. In this way, by fixing the transfer roll 38 and the fixing device 40 to the lid 46, the transfer roll 38 and the fixing device 40 move together with the lid 46 when the lid 46 is opened and closed. .

  Therefore, the transfer roll 38 and the fixing device 40 can be retracted from the space where the process cartridge 26 is attached / detached, and when replacing the process cartridge 26, there is no risk of touching the high temperature part by mistake, and operability is improved. To do.

  Here, by removing the process cartridge 26 toward the manual feed tray 32 and the discharge tray 44 (in the direction of arrow A), the operator can perform various operations at the same standing position, and the operation becomes easy. Work efficiency can be achieved.

  As shown in FIGS. 1 and 3, a recording sheet insertion port 48 is provided on the side surface 16 </ b> B of the main body 16, and the recording sheet supplied from the recording sheet insertion port 48 is transferred to the photosensitive drum of the U-turn conveyance path 36. 12 is joined to the U-turn conveyance path 36 from the joining portion 50 located upstream of the guide 12 and guided to the image forming portion 14 by a resist roll pair 49. As a result, the recording sheet is conveyed on a substantially straight line, so that even a recording sheet such as cardboard can be conveyed.

  Further, the sheet conveyance path 62 is formed so as to rise in a substantially vertical direction from the paper feed cassette 55 of the paper feed cassette unit 52 and guide it to the junction 50. Thereby, the projected area of the image forming apparatus 10 can be reduced.

  On the other hand, as shown in FIG. 3, the recording sheet discharged to the discharge tray 44 is reversely conveyed in the direction opposite to the discharge direction and returned to the sheet conveyance path 62, thereby enabling duplex printing. Thus, by providing the return conveyance path 68 for duplex printing at the lower part of the main body part 16, the operability of the manual feed tray 32 arranged at the upper part of the main body part 16 is not affected at all. Double-sided units can be added.

  Here, as shown in FIGS. 2 and 3, the paper feed cassette unit 52 and the return conveyance unit 64 are provided independently and detachably provided to the main body 16. However, the present invention is not limited to this. .

  For example, as shown in FIGS. 6 and 7, the return conveyance path 78 may be composed of a main body 80 and a paper feed cassette 82. Specifically, a transport unit 88 including a part of the return transport path 78, a transport unit 84, and a storage unit 86 to which the paper feed cassette 82 can be attached and detached can be attached to the main body unit 80, and the return transport is performed. The upper part 90A of the pair of conveying rolls 90 disposed as a part of the path 78 so as to face the attachment surface 72 is pivotally supported in a state where it is exposed to the storage part 86. On the other hand, a conveyance path 92 is provided at the front end of the side wall of the paper feed cassette 82, and the lower portion 90B of the conveyance roll pair 90 is rotatably supported.

  As a result, the return conveyance path 78 is configured in a state where the paper feed cassette 82 is mounted in the storage portion 86. Thus, by configuring the return conveyance path 78 with the main body 80 and the paper feed cassette 82, the height of the image forming apparatus 94 can be suppressed when the return conveyance path 78 is added.

  Here, a pressing plate 82A is provided at the bottom of the paper feed cassette 82 so as to be swingable upward, and the recording sheet accommodated in the paper feed cassette 82 is fed into a feed roll for separating and conveying the recording sheet. 58, when the recording sheet passes through the return conveyance path 78 in order to supply the recording sheet to the conveyance unit 84, the pressing plate 82 </ b> A is swung downward to return the recording sheet in the paper feeding cassette 82. It is necessary to retreat from the conveyance path 78.

  In this embodiment, the present invention is applied to an xerographic image forming apparatus. However, the present invention is not limited to this, and an inkjet method may be used.

1 is a configuration diagram of an image forming apparatus according to an embodiment of the present invention, in a state where a return conveyance unit is not mounted. 1 is an exploded view of each configuration of an image forming apparatus according to an embodiment of the present invention. 1 is a configuration diagram of an image forming apparatus according to an embodiment of the present invention. 1 is a configuration diagram of an image forming apparatus according to an embodiment of the present invention, showing a state where a lid is opened. FIG. It is a block diagram which shows the 1st modification of the image forming apparatus which concerns on embodiment of this invention. It is a block diagram which shows the 2nd modification of the image forming apparatus which concerns on embodiment of this invention. FIG. 6 is a configuration diagram illustrating another example of a return conveyance path that constitutes the image forming apparatus according to the embodiment of the present invention. FIG. 6 is an exploded view showing another example of a return conveyance path constituting the image forming apparatus according to the embodiment of the present invention. It is a block diagram of a conventional image forming apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 12 Photosensitive drum (Image carrier, recording means)
14 Image forming unit (recording means)
16 Main body 26 Process cartridge 30 Mounting surface 32 Manual feed tray 36 U-turn conveyance path 38 Transfer roll (transfer means, recording means)
40 Fixing device (fixing means, recording means)
46 Lid 48 Recording sheet insertion port 50 Junction section 55 Paper feed cassette (sheet cassette)
62 Sheet conveying path 66 Reverse conveying section (sheet reversing means)
68 Return conveyance path 70 Junction conveyance path (return conveyance path)
72 Attaching surface 77 Sheet conveyance path 78 Return conveyance path 80 Main body 82 Paper feed cassette 84 Conveyance section (sheet conveyance path)
92 Transport path (return transport path)
94 Image forming apparatus

Claims (12)

A manual feed tray placed on the upper part of the main body provided with recording means for forming an image, and placed with the recording sheet exposed;
The recording sheet placed on the manual feed tray makes a U-turn above the recording means, an image is formed by the recording means, and the U-turn is discharged to a discharge tray disposed substantially parallel to the manual feed tray. A transport path;
An image forming apparatus comprising:   An image carrier that carries toner; a transfer unit that transfers a toner image formed on the image carrier to a recording sheet; and a fixing unit that fixes the toner image transferred to the recording sheet. The image forming apparatus according to claim 1, further comprising:   The image forming apparatus according to claim 2, wherein the image carrier is disposed under the transfer unit.   The image forming apparatus according to claim 1, wherein the manual feed tray is detachably provided, and an attachment surface from which the manual feed tray is removed is substantially horizontal.   The image forming apparatus according to claim 4, wherein a recording sheet insertion port for feeding a recording sheet to the transfer unit is provided on a side surface of the main body.   The image forming apparatus according to claim 5, wherein the main body is stacked on the mounting surface. A sheet cassette that can be added to the lower portion of the main body and can store recording sheets;
A sheet conveyance path that rises from the sheet cassette in a substantially vertical direction and guides it to the transfer unit;
An image forming apparatus according to claim 1, comprising: Sheet reversing means for reversing and conveying the recording sheet discharged to the discharge tray in a direction opposite to the discharge direction;
A return conveyance path that is disposed at a lower part of the main body and returns the reversely conveyed recording sheet to the sheet conveyance path;
The image forming apparatus according to claim 7, further comprising:   The image forming apparatus according to claim 8, wherein a cover body that covers an upper portion of the sheet cassette constitutes at least a part of the return conveyance path. An image carrier that carries toner, a transfer unit that transfers a toner image formed on the image carrier to a recording sheet, a fixing unit that fixes the toner image transferred to the recording sheet, and an image are formed. A manual feed tray placed on the upper portion of the main body provided with the recording means and placed with the recording sheet exposed; a recording sheet insertion opening provided on a side surface of the main body for sending the recording sheet to the transfer means; A sheet cassette disposed at the bottom of the main body and capable of storing recording sheets,
An image forming apparatus comprising: a merging unit capable of merging recording sheets supplied from the manual feed tray, the sheet insertion port, and the sheet cassette upstream of the transfer unit.   The image forming apparatus according to claim 10, wherein the manual feed tray and the sheet cassette are detachably provided, and an attachment surface from which the manual feed tray and the sheet cassette are removed is substantially horizontal.   A process cartridge provided with a lid capable of opening and closing the inside of the main body, wherein the manual feed tray, the transfer means and the fixing means are fixed to the lid, and the image carrier is accommodated therein. The image forming apparatus according to claim 10, wherein the image forming apparatus is detachably provided.

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