JP2000338841A - Electrophotographic image forming apparatus - Google Patents

Abstract

An object of the present invention is to eliminate the possibility of an erroneous operation when replacing a process cartridge without increasing the size of an image forming apparatus main body and without increasing costs. SOLUTION: A lever-shaped operating member 49 is provided on a main body cover of the apparatus main body together with the transfer device so as to protrude inward. Then, when the process cartridge 20 is inserted into the apparatus main body and the main body cover is closed, the main body cover is moved together with the main body cover, the operating member 49 is engaged with the engaging portion 48b, and the relay member 48 is rotated. Of the shutter 18 through the engagement of the gear 48a of the shutter 48 and the gear 47 of the shutter 18.
Is opened, and the transfer window of the process cartridge 20 is opened. At the same time, the transfer device is approached to face the image carrier through the transfer window. At the same time, the operating member 49 enters the regulating position on the front side in the removing direction of the process cartridge 20, and regulates the removal of the process cartridge 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic system, such as a copying machine, a printer, a facsimile, or a multifunction machine using a laser, for forming an image formed on an image carrier such as a photoreceptor. The present invention relates to an image forming apparatus that transfers and records on a recording medium such as a sheet or an OHP sheet.

[0002]

2. Description of the Related Art Conventionally, this type of image forming apparatus includes:
A process cartridge is configured by including some of the process means such as a charging device, a developing device, and a cleaning device in a single cartridge case together with the image carrier, so that the image forming apparatus main body can be exchanged at a time, thereby improving serviceability. In addition, there is one that improves the maintenance performance and the size of the entire apparatus body.

In such a process cartridge, a transfer window is provided, and the toner image formed on the image carrier is transferred to a recording medium through the transfer window. However, if the image carrier is left exposed through the transfer window, the image carrier may be deteriorated or damaged. To protect the image carrier by closing the shutter.

When the process cartridge is mounted on the main body of the image forming apparatus and the right cover of the main body, for example, is closed, the shutter is opened by an operating member provided on the right cover of the main body and the transfer device provided on the right cover of the main body. Was brought close to the image carrier through the transfer window.

Conversely, when the right cover of the main body is opened to take out the process cartridge from the main body of the image forming apparatus, the operating member is retracted to close the shutter, and
The transfer device is separated from the image carrier. In many image forming apparatuses, for example, the front cover of the main body is opened on the front side of the main body of the apparatus, and the process cartridge is pulled out to the front side for easy handling. Then, a new process cartridge was inserted, and the front cover and the right cover were closed.

In such an image forming apparatus,
Before opening the right cover of the main body and separating the transfer device from the image carrier, if the user mistakenly opens the front cover of the main body and removes the process cartridge, the image carrier may be scratched by rubbing with the transfer device. The process cartridge may be damaged.

Therefore, in order to prevent such erroneous operation,
Conventionally, a regulating member was provided on the right cover of the main unit, and it moved together with the opening and closing operation of the right cover of the main unit.When the right cover of the main unit was opened, it was possible to remove the process cartridge. I was trying to regulate.

[0008]

However, in such a conventional image forming apparatus, the operating member for opening and closing the shutter and the regulating member for regulating the removal of the process cartridge are provided separately on the right cover of the main body. These occupied spaces need to be overlapped, and the size of the image forming apparatus main body increases, and the cost increases.

An object of the present invention is to eliminate the possibility of erroneous operation when replacing a process cartridge without increasing the size of the image forming apparatus main body and without increasing the cost.

[0010]

Accordingly, the present invention provides
A process cartridge includes at least an image carrier, a transfer window used to transfer an image formed on the image carrier, and a shutter for opening and closing the transfer window. The apparatus main body is provided with a main body cover which is opened and closed when the process cartridge is exchanged, and the main body cover is moved together with the opening / closing operation of the main body cover. An electrophotographic image forming apparatus that provides a transfer device that faces the image carrier through the transfer window when the main body cover is closed.
Interlocking with the opening and closing operation of the main body cover, a restriction release position for releasing the removal restriction of the process cartridge,
Alternatively, it is a restriction position for restricting removal.

The shutter may be urged in the closing direction based on gravity to open the shutter against gravity when the operating member is moved in conjunction with the closing operation of the main body cover. Further, it is preferable that the process cartridge can be exchanged with respect to the image forming apparatus main body in the axial direction of the image carrier.

A relay member having a gear portion that meshes with the gear portion of the shutter and an engaging portion with which the operating member engages is provided, and the operating member is moved via the relay member in conjunction with the opening / closing operation of the main body cover. At this time, the shutter may be closed or opened.

When the main body cover is closed, the operating member enters the regulating position on the front side of the process cartridge withdrawal direction and regulates the removal of the process cartridge. When the main body cover is opened, the operating member is positioned on the front side of the process cartridge withdrawal direction. It is preferable to move to the restriction release position retracted from the printer and release the removal restriction of the process cartridge.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of a main part of a laser copying machine according to the present invention. FIG. 2 shows a process cartridge provided in the laser copying machine as viewed from a side opposite to the transfer side by opening a shutter, and FIG. 3 shows a state in which the shutter is closed and a part of the cleaning device is opened.
Shown from the transfer side.

Reference numeral 10 in the figure denotes a drum-shaped photosensitive member serving as an image carrier. As can be seen from FIG. 1, around the photoreceptor 10, a developing device 12 and a transfer device 13 are sequentially arranged in a rotating direction indicated by an arrow A of the photoreceptor 10 from a roller-shaped charging device 11 provided on the side thereof. A cleaning device 15 is provided on the sheet separating device 14.

When a copy is to be made, a document is set on a contact glass (not shown) and a copy switch is pressed, as is well known. Then, the image of the document is read by an optical reading device (not shown), and at the same time, the paper P is transported between the photoconductor 10 and the transfer device 13.

On the other hand, the surface of the photoconductor 10 is uniformly charged by the charging device 11 with its rotation, and the surface is irradiated with a laser beam L from an optical writing device (not shown) to perform writing. An electrostatic latent image of the read original image is formed thereon, and subsequently toner is attached when passing the position of the developing device 12 to sequentially visualize the electrostatic latent image. Then, the toner image formed by the visualization is transferred by the transfer device 13 onto the sheet P conveyed between the photoconductor 10 and the transfer device 13 as described above.

After the transfer, the paper P is discharged by the paper separating device 14, separated from the photoreceptor 10 to which it is electrostatically attached, transported to a fixing device (not shown), where the transferred image is fixed. To the paper discharge section. A separating claw may be provided in place of the sheet separating device 14 so as to be mechanically separated from the photoconductor 10.

On the other hand, the photoreceptor 10 after the image transfer is cleaned by scraping off the residual toner remaining on the surface with a cleaning blade 17 provided in a cleaning device 15 and then removing the charge by a discharge lamp (not shown). Initialize the surface potential.

In this laser copying machine, a charging device 11, a developing device 12, a cleaning device 15 and the like together with the photoreceptor 10 are arranged as shown in FIGS.
The process cartridge 20 is integrally formed by the two cartridge cases 19.

The process cartridge 20 has a transfer window used for transferring a toner image formed on the image carrier, and opens and closes the transfer window as shown by reference numeral 18 in FIGS. A photoconductor shutter is provided.
Then, in the state set in the copying machine main body, FIG.
As shown in FIG. 3, the photoconductor shutter 18 is opened to open the transfer window, and when not set, the photoconductor shutter 18 is closed to cover the transfer window as shown in FIG.

Now, in such a laser copying machine,
As shown in FIG. 1, the developing device 12 described above has a configuration in which a developer accommodating section 21 is provided on a lower side and a developer carrying section 22 is provided on an upper side. The developer accommodating section 21 is provided with a first agitating member 23 and a second agitating member 24 for accommodating a two-component developer and transporting the developer while agitating the developer. Although not shown, a toner concentration sensor for detecting a mixing ratio between the toner and the carrier in the developer is provided. Before use, the space between the developer holding portion 22 and the developer carrying portion 22 is sealed with a seal member (not shown).

As shown in FIG. 4, a new toner supply port 25 and a recycled toner supply port 26 are provided in the developer accommodating section 21 on the front side, respectively, and are opened upward.
Then, the toner entering from the supply ports 25 and 26 is
The first agitating member 23 and the second agitating member 24 convey the ink so as to circulate in the direction indicated by the arrow in FIG.

On the other hand, as shown in FIG.
2, a developing roller 28 is provided at a position facing the photoreceptor 10 through the developing window 27. Further, a developing doctor 29 for controlling the supply amount of the developer to the photoconductor 10 is provided.

The cleaning device 15 provided on the photoreceptor 10 has a screw-shaped toner conveying member 3 for conveying the residual toner scraped off by the cleaning blade 17 into a cleaning case portion 15 a of a cartridge case 19.
0 is arranged in the axial direction of the photoconductor 10. As shown in FIG. 2, the toner conveying member 30 has one end 31 of a shaft 31 thereof.
a is provided so as to enter the fall path 35 from the fall path entrance 33 provided above the front plate portion 19 a of the cartridge case 19.

The fall path 35 is provided with a peripheral wall 36 provided on the outer surface of the front plate 19a so as to surround the fall path 35, and the front side thereof is airtightly covered with a front cover which is removed and omitted in FIG. The falling path 35 includes a bottom surface 36 a of the peripheral wall 36.
The recycled toner supply port 2 of the developing device 12 described above
A fall path exit 37 leading to 6 is provided. Further, the peripheral wall 36 is partially inclined between the falling path exit 37 and the falling path entrance 33, and a falling surface 36b of the residual toner is formed on the inner surface of the inclined portion.

At the time of copying, the developing device 12 drives a drive motor (not shown) to transmit the drive to rotate the developing roller 28 and to rotate the stirring members 23 and 24 to stir the developer. The toner and the carrier are conveyed to the developing roller 28 while being frictionally charged. On the other hand, the developing roller 2
The toner in the developer is electrostatically attached to the surface of the photoreceptor 10 by applying a predetermined bias to 8, and the latent image on the surface is visualized.

On the other hand, in the cleaning device 15, the rotation of the photosensitive member 10 is transmitted via a gear to transmit the toner
Is driven to rotate, and the residual toner removed from the photoconductor 10 is transported by the toner transporting member 30 to be cleaned.
2, is dropped on the falling surface 36 b from the falling path entrance 33 as shown by the arrow in FIG. 2, and further slides down on the falling surface 36 b as shown by the arrow, and recycled toner is supplied from the falling path exit 37. Developer container 2 through port 26
Collect in 1.

FIG. 5 shows the appearance of the above-described laser copying machine. In the figure, reference numeral 40 denotes an apparatus main body, 41 denotes a main body front cover provided on the front side of the apparatus main body 10 so as to be vertically openable and closable, and 42 denotes a main body right cover similarly provided on the right side so as to be vertically openable and closable.

A lever-shaped operating member 49 protruding inward is provided on the main body right cover 42 integrally with or separately from the main body right cover 42. The actuating member 49 moves together with the opening / closing operation of the main body right cover 42, and operates in a manner described later in detail to operate the photosensitive member shutter 1 described above.
8. Close or open 8. As shown in FIG. 6, the operating member 49 has an upper edge provided in an arc shape along a distance r from the opening / closing center axis c of the main body right cover 42 so as to move about the opening / closing center axis c.

Although not shown, the main body right cover 4
2, the transfer device 13 described above is provided. When the main body right cover 42 is closed, the transfer device 13 faces the photoconductor 10 through the transfer window.

Then, as shown in FIG. 5, by opening the main body front cover 41 and opening the main body right cover 42, the apparatus main body 40 is opened through the opening 45a of the main body front side plate 45.
The process cartridge 20 can be inserted and removed in the axial direction (the direction of the arrow a in the drawing), and is supported exchangeably between a main body front side plate 45 of the apparatus main body 40 and a main body rear side plate (not shown). The jam processing is performed by opening only the main body right cover 42.

Now, the process cartridge 20 will be described in further detail. As shown in FIG. 7, the process cartridge 20 supports both ends of the support shaft 46 with the cartridge case 19, and supports the above-described photosensitive member shutter 18 so as to be freely opened and closed. A gear portion 47 is provided at one end of the support shaft 46. The gear 47 meshes with the gear of the relay member 48.

Actually, the gear portion 47 and the relay member 48
Are covered with a cover 49, and some of them are invisible from the outside. Therefore, the gear portion 47 and the relay member 48 will be described with reference to FIGS. 8 and 9 with the cover 49 removed.

As shown in FIGS. 10 and 11, the relay member 48 is provided with an engaging portion 48b and a shaft hole 48c together with the gear portion 48a. The gear portion 48a and the engaging portion 48b are provided with a step and extend in opposite directions. Shaft hole 4
A support shaft 51 erected on the front plate portion 19a is inserted into 8c, and is rotatably supported by the cartridge 19.

As shown in FIGS. 11 and 12, the gear portion 48a is provided outside the main body front side plate 45.
7 so that the engaging portion 48b engages with the operating member 49 on the inside. As described above, since the step is provided between the gear portion 48a and the engaging portion 48b, the operating member 49 does not have to worry about interference with the gear portion 48a, and
Can be made smaller.

When the relay member 48 is set upside down, the engaging portion 48b is
Will not be engaged. Therefore, in the illustrated example, FIG.
As shown in FIG. 10, a shaft hole 48c of the relay member 48 is formed with a diameter D1 and a diameter D2 larger than that by providing a step in the middle, and as shown in FIG. And the diameter d1 at the tip and the diameter d2 larger than
And the relay member 48 is turned upside down so that it cannot be attached.

Now, when the main body right cover 42 shown in FIG. 5 is opened to replace the process cartridge 20, it moves together with it, and the transfer device 13 moves away from the photoreceptor 10 and operates from the engaging portion 48b. The member 49 separates,
As shown in FIG. 13, the relay member 48 is rotated by its own weight w based on gravity, and closes the photoreceptor shutter 18 via engagement between the gear portion 48a and the gear portion 47.

When the photoreceptor shutter 18 is closed, its gravitational force W is applied as shown in FIG.
As shown in FIGS. 15 and 16, the photoconductor shutter 18 is completely closed. After that, or beforehand with the exterior right cover 42, the main body front cover 41 shown in FIG. 5 is opened, and the process cartridge 20 is pulled out from the image forming apparatus main body 40.

Next, the process cartridge 20 is replaced, and a new process cartridge 20 is inserted into the apparatus main body 40. Thereafter, when the main body front cover 41 and the main body right cover 42 are closed, the main body right cover 42 is moved together with the main body right cover 42, and the operating member 49 is engaged with the engaging portion 48b, and the relay member 48 is turned against the gravity. Move. Then, as shown in FIGS. 17 and 18, the photoconductor shutter 18 is opened via the engagement between the gear portion 48a and the gear portion 47.

In the present invention, the main body right cover 4
When 2 is closed, as shown in FIGS. 17 and 18, the operating member 49 enters the regulating position on the front side in the removing direction of the process cartridge 20 in conjunction therewith, and regulates the removal of the process cartridge 20.

Naturally, when the main body right cover 42 is closed, the operating member 49 blocks, so that a new process cartridge 20 cannot be mounted.

Conversely, when the right cover 42 of the main body is opened, the operating member 49 moves to the restriction release position retracted from the front side of the process cartridge 20 in the removal direction, and the restriction is released to allow the process cartridge 20 to be removed. .

In the illustrated example, a projection 50 is provided on the front plate portion 19a of the cartridge 19, and the projection 50 regulates the rotation range of the relay member 48, and the operating member 49 and the engagement portion 48b
And the gear portion 47 and the gear portion 4
8a is always held so as to be surely engaged.

[0045]

As described above, according to the present invention, the process cartridge is provided with a shutter for protecting the image carrier, and the operating member for opening and closing the shutter is used for opening and closing the main body cover of the image forming apparatus main body. In conjunction therewith, it is set to a restriction release position for releasing the removal restriction of the process cartridge, or to a restriction position for restricting the removal of the process cartridge.

Therefore, according to the present invention, both opening and closing of the shutter and control of removal of the process cartridge can be performed by one operating member, so that the occupied space can be reduced and the size of the image forming apparatus main body can be reduced. Further, it is possible to eliminate the possibility of damaging the image carrier or damaging the process cartridge due to an erroneous operation when replacing the process cartridge, while enabling cost reduction.

According to the second aspect of the present invention, by urging the shutter in the closing direction based on gravity, an extra urging member is unnecessary, and the cost can be further reduced.

According to the third aspect of the present invention, since the process cartridge can be exchanged in the axial direction of the image carrier, the size of the take-out opening of the process cartridge can be reduced to further reduce the size.

According to the fourth aspect of the present invention, the shutter can be opened and closed without increasing the size by using the relay member to open and close the shutter in conjunction with the opening and closing operation of the main body cover.

According to the fifth aspect of the invention, the operation member is inserted into the front side of the process cartridge in the removing direction to regulate the removal of the process cartridge, or is retracted from the near side to release the regulation. From
With a simple configuration, the operating member can be set at the restriction position or at the restriction release position, and the size can be further reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a main part of a laser copying machine according to the present invention.

FIG. 2 is a perspective view showing a process cartridge provided in the laser copying machine when a shutter is opened and viewed from a side opposite to a transfer side.

FIG. 3 is a perspective view showing the process cartridge when a shutter is closed and a part of a cleaning device is opened, as viewed from a transfer side.

FIG. 4 is a perspective view of a developer accommodating portion provided in the process cartridge.

FIG. 5 is an external perspective view of the above-described laser copying machine.

FIG. 6 is an operation explanatory view of an operation member provided in the main body right cover.

FIG. 7 is an external perspective view of the process cartridge.

FIG. 8 is a front view of the apparatus with a cover removed.

FIG. 9 is an external perspective view of the apparatus with a cover removed.

FIG. 10 is a perspective view of a relay member provided in the process cartridge and a support shaft for supporting the relay member.

FIG. 11 is a longitudinal sectional view of a relay member.

FIG. 12 is a cross-sectional view showing an attached state of the relay member.

FIG. 13 is a front view showing a state immediately after opening a main body right cover of the apparatus main body.

FIG. 14 is a front view showing that the relay member and the photoconductor shutter rotate by gravity.

FIG. 15 is a front view of a part of the process cartridge in a state where the photoconductor shutter is completely closed.

FIG. 16 is a perspective view of the same.

FIG. 17 is a front view illustrating a state of the process cartridge when the main body right cover of the apparatus main body is closed after replacing the process cartridge.

FIG. 18 is a perspective view at that time.

[Explanation of symbols]

 Reference Signs List 10 photoconductor (image carrier) 13 transfer device 18 photoconductor shutter (shutter) 19 cartridge case 19a front plate 20 process cartridge 40 device main body 41 main body right cover (main body cover) 42 main body front cover 45 main body front side plate 46 support shaft 47 Gear part 48 Relay member 48a Gear part 48b Engagement part 48c Shaft hole 49 Operating member 50 Projection 51 Support shaft

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Jiji Mizuishi 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Toshitaka Yamaguchi 1-3-6 Nakamagome, Ota-ku, Tokyo Share Inside Ricoh Company (72) Inventor Kenzo Tatsumi 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Inside Ricoh Company (72) Inventor Noriyuki 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh Company (72) Inventor Mayumi Ohori 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. (72) Inventor Hiroshi Mizusawa 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. (72) Invention Person Hideki Yoshinami 1-3-6 Nakamagome, Ota-ku, Tokyo F-term in Ricoh Co., Ltd. (Reference) 2H071 BA04 BA13 BA14 BA16 BA23 BA29 BA36 DA15

Claims (5)

[Claims] 1. A process cartridge comprising at least an image carrier, a transfer window used to transfer an image formed on the image carrier, and a shutter for opening and closing the transfer window. The cartridge is exchangeably stored in the main body of the image forming apparatus. The main body of the apparatus is provided with a main body cover that opens and closes when the process cartridge is exchanged. An electrophotographic image forming apparatus, comprising: an operating member that moves and closes or opens the shutter, and further includes a transfer device that faces the image carrier through the transfer window when the main body cover is closed. In conjunction with the opening and closing operation of the body cover,
An electrophotographic image forming apparatus, which is a restriction release position for releasing the process cartridge removal restriction or a restriction position for removing the process cartridge. 2. The shutter is urged in a closing direction based on gravity to open the shutter against gravity when the operating member is moved in conjunction with a closing operation of the main body cover. 2. The electrophotographic image forming apparatus according to 1. 3. The electrophotographic image forming apparatus according to claim 1, wherein the process cartridge is exchangeable with respect to the image forming apparatus main body in the axial direction of the image carrier. 4. A relay member having a gear portion that meshes with a gear portion of the shutter and an engaging portion with which the operating member engages, and the relay member interlocks with the opening and closing operation of the main body cover via the relay member. The electrophotographic image forming apparatus according to claim 1, wherein the shutter is closed or opened when the operating member is moved. 5. When the main body cover is closed, the operating member enters the restricting position on the front side in the direction in which the process cartridge is taken out to regulate the removal of the process cartridge, and when the main body cover is opened, the operating member operates. 2. The electrophotographic image forming apparatus according to claim 1, wherein the member is moved to the restriction release position retracted from the front side in the removal direction of the process cartridge to release the removal restriction of the process cartridge. 3.