JP3537308B2 - Electrophotographic apparatus and process cartridge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a copying machine, a printer, a facsimile, a multifunction machine thereof, and the like, which forms an image on an image carrier by repeating, for example, charging, writing, developing, transferring, cleaning, and discharging. The present invention can be applied to an image forming apparatus that transfers the image and records the image on a recording medium such as paper. In particular, the invention relates to an image forming apparatus in which at least an image carrier is provided to constitute a process cartridge, and the process cartridge is detachably attached to an image forming apparatus main body. And preparing for such an image forming apparatus
Regarding the process cartridge.

[0002]

2. Description of the Related Art Conventionally, in order to reduce the size of an image forming apparatus and for convenience of maintenance, a process cartridge is formed by integrally providing an image carrier and a charging device or a cleaning device. In some cases, a process cartridge is made detachable from an image forming apparatus main body.

In this type of image forming apparatus, a separation claw is provided on a process cartridge, and a tip of the separation claw is pressed against a peripheral surface of an image carrier, and a recording medium after an image is transferred from the image carrier. There is something that separates.

[0004]

However, in such a conventional image forming apparatus, when the process cartridge is taken out from the main body of the image forming apparatus, the tip of the separation claw is strongly pressed against the image carrier. In such a case, there is a problem that if the image carrier is rotated in such a case, the image carrier is damaged.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming apparatus of the type described above, which eliminates the possibility of damaging the peripheral surface of the image carrier even if the process cartridge is taken out of the image forming apparatus during maintenance or the like. It is in.

[0006]

According to a first aspect of the present invention, there is provided an image forming apparatus, comprising: an image forming apparatus configured to form an image to be transferred to a recording medium according to an embodiment described with reference to the following drawings; A process cartridge 20 provided with a carrier 12 and at least the image carrier 12 and detachably mounted on an image forming apparatus main body such as a copying machine main body 10; and a process cartridge 20 provided on the process cartridge 20 and provided on the image forming apparatus main body. When the image carrier 1 is opened, it is opened.
2 was opened, and carrier cover 35 which covers the image bearing member 12 is closed when taken out of the image forming apparatus main body, the responsible
When the carrier cover 35 is opened, the rotation is transmitted when the carrier cover 35 is opened, and the recording medium after the image transfer is separated from the image carrier 12 by pressing against the image carrier 12. On the other hand, the times when closing the carrier cover 35
And a separating claw 30 provided on the process cartridge 20 for transmitting the movement and separating from the image carrier 12.

According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, when the carrier cover 35 is closed as in an embodiment described with reference to the following drawings, for example, It is characterized in that the separation claw 30 is covered with a body cover 35.

According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect, as in an embodiment described with reference to the following drawings, for example, Spur 32 to help transport
And the spur 32 is covered by the carrier cover 35 when the carrier cover 35 is closed. The invention according to claim 4 is a process cartridge.
In FIG. 20, for example,
As in the embodiment, an image forming apparatus such as
Detachably configured for Okimoto body decal to the recording medium
The image carrier 12 for forming an image and the main body of the image forming apparatus
When attached, open to release the image carrier 12 and
When taken out of the apparatus main assembly, the image carrier 12 is closed.
Carrier cover 35 that covers
When the carrier cover 35 is opened,
And transferred to the image carrier 12 to transfer the image after image transfer.
While separating the recording medium from the image carrier 12,
When the body cover 35 is closed, its rotation is transmitted and the image
A separating claw 30 for separating from the carrier 12;
And features.

According to the present invention, when the process cartridge 20 is removed from the image forming apparatus main body at the time of maintenance or the like, the carrier cover 35 is closed and the image carrier 1 is closed.
2 and separate the separation claw 30 from the image carrier 12. At that time, in the invention described in claim 2, the separation claw 30 is covered with the closed carrier cover 35, and in the invention described in claim 3, the separation claw 30 is provided separately or separately from the separation claw 30.
Together with the spur 32.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an overall schematic configuration of a laser copying machine according to the present invention. Reference numeral 10 in the figure
Denotes a copying machine main body. The apparatus main body 10 is provided with a drum-shaped image carrier 12. Around the image carrier 12, a charging device 13, a writing device 14, a developing device 15, a transfer device 16, a cleaning device 17, and the like are provided.

As the image carrier 12 rotates in the counterclockwise direction in the figure, the surface thereof is first uniformly charged by a charging device 13 and then irradiated with a laser beam L by a writing device 14 as is well known. An electrostatic latent image is formed by writing, and then the toner is adhered by a developing device 15 to visualize the latent image, and then the image formed on the image carrier 12 is transferred by a transfer device 16. Recording on a recording medium such as paper.

After the image is recorded on the recording medium, the transferred image is fixed by a fixing device 18 and then discharged onto a paper discharge stack unit 19. The image carrier 12 after the image transfer is cleaned by a cleaning device 17. Thus, the toner remaining on the image carrier 12 is removed, and the charge is removed to prepare for the image formation again.

In the illustrated laser copying machine, as described above, the image carrier 12 and the charging device 13, the developing device 15, and the cleaning device 17 are integrally provided in order to reduce the size and for convenience of maintenance. A process cartridge 20 as shown in FIG. 2 is formed, and the process cartridge 20 is detachable from the copier main body 10.

The developing device 15 provided in the cartridge case 21 of the process cartridge 20 includes conveying screws 22 and 23, a developing sleeve 24, a doctor blade 2
5, a toner density sensor 26 and the like.

Further, the process cartridge 20 is provided with two separation claws 30 by pressing the front end against the image carrier 12. The separation claw 30 is fixed on a separation claw shaft 31 provided in parallel with the image carrier 12.

A spur 32 is fixedly provided on the separation claw shaft 31 near the separation claw 30 as shown in FIG. The spur 32 is an auxiliary member for conveying the recording medium, and although not shown, is provided with claws on the entire peripheral surface.

On the separation claw shaft 31, a separation claw shaft gear 33 is fixed at one end. The separation claw shaft gear 33 meshes with the cover shaft gear 34. The cover shaft gear 34 is fixed on a cover shaft 36 of the carrier cover 35.

The carrier cover 35 is supported rotatably about a cover shaft 36. It is normally urged in a closing direction by a coil spring (not shown). The carrier cover 35 is provided with a recess at a position corresponding to the separation claw 30 and the spur 32 to form a storage section 35a.

On the other hand, a transmission gear 37 is fixed to the end of the cover shaft 36. The transmission gear 37 meshes with a fan-shaped tooth portion 38 a of the rotating body 38. The rotating body 38 has a fan-shaped tooth portion 38.
A cam portion 38b is provided at a position symmetrical to a.

As shown in FIG. 4, a lever 39 provided integrally with a body cover (not shown) of the apparatus body 10 is engaged with the cam portion 38b. Then, the carrier cover 35 is held at the open position as shown in FIG. 3 against the urging force of the coil spring for urging the carrier cover 35.

When the main body cover (not shown) is opened in order to clear the jam or replace the process cartridge 20, the lever 39 moves in the direction indicated by the arrow in FIG. Then, the rotating body 38 is biased by the biasing force of the coil spring biasing the carrier cover 35.
Is rotated in the counterclockwise direction in FIG.
Is rotated clockwise, and the carrier cover 35 also rotates in the same direction about the cover shaft 36 integrally with the transmission gear 37.

Then, the rotation of the cover shaft 36 is transmitted to the separation claw shaft 31 via the engagement between the cover shaft gear 34 and the separation claw shaft gear 33, and the separation claw 30 is rotated counterclockwise to rotate Is separated from the image carrier 12.

When the main body cover is completely opened, the lever portion 39 is retracted to the position shown in FIG. 5, and the carrier cover 35 is completely closed as shown in FIG. U. At this time, the separation claw 30 and the spur 32 are stored in the two storage portions 35a of the carrier cover 35, respectively.

After the jam has been cleared or the process cartridge 20 has been replaced, the process cartridge 20 is mounted in the copier main body 10 again, and the main body cover is closed.
The lever 39 moves in the direction indicated by the arrow in FIG.

Then, the tip of the lever portion 39 is
b, and rotates the rotating body 38 in the clockwise direction in FIG. 5 against the biasing force of the coil spring biasing the carrier cover 35, and rotates the transmission gear 37 in the counterclockwise direction. The carrier cover 35 integrally rotates about the cover shaft 36 in the same direction.

Then, the rotation of the cover shaft 36 is transmitted to the separation claw shaft 31 through the meshing of the cover shaft gear 34 and the separation claw shaft gear 33, and the separation claw 30 is rotated clockwise to adjust the tip. It is pressed against the image carrier 12.

Then, when the body cover is completely closed,
The lever 39 is again in the state shown in FIG. 4, and the carrier cover 35 is completely opened as shown in FIG.
To release.

Thus, the recording medium after the image transfer is separated from the image carrier 12 by the separation claw 30 and guided to the fixing device 18 by assisting the conveyance by the spur 32.

[0029]

Therefore, according to the present invention, when the process cartridge is taken out of the image forming apparatus main body during maintenance or the like, the carrier cover is closed to cover the image carrier, and is separated from the image carrier. Since the nails are separated, even if the image carrier is rotated, the image carrier is not damaged, the film of the image carrier is prevented from being scraped, and the life can be extended.

According to the second aspect of the present invention,
When the process cartridge is taken out at the time of jam clearance or the like, the separation claws are covered with the carrier cover, so that there is no risk of the user touching the separation claws and being injured.

According to the third aspect of the invention, when the process cartridge is taken out, the spur covers the carrier cover separately from the separation claw or together with the separation claw, so that the user touches the spur and is injured. The fear can be eliminated.

[Brief description of the drawings]

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

FIG. 2 is an overall schematic configuration diagram of a process cartridge used in the copying machine.

FIG. 3 is a schematic perspective view of an area around an image carrier of the process cartridge.

FIG. 4 is a side view of the process cartridge.

FIG. 5 is a side view of the process cartridge in a state where a main body cover of the copier main body is opened.

FIG. 6 is a schematic perspective view of an area around an image carrier of the process cartridge with its main body cover opened.

[Explanation of symbols]

10 Copying machine body (image forming apparatus body) 12 Image carrier 20 process cartridge 30 Separating claws 31 Separating claw shaft 32 spurs 33 Separating claw shaft gear 34 Cover shaft gear 35 Carrier cover 36 Cover axis 37 Transmission gear 38 Rotating body 39 Main unit cover lever

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenzo Tatsumi 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Hiroshi Mizusawa 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Ken Amamiya 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. Inside Ricoh Co., Ltd. (72) Hideki Yoshinami 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. Ricoh Co., Ltd. (72) Inventor Mayumi Ohori 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. Ricoh Co., Ltd. (56) References JP-A-60-104961 (JP, A) JP-A-3-140971 ( JP, A) JP-A-62-178991 (JP, A) JP-A-63-174642 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 13/14-13/16 G03G 15/00 G03G 15/00 550 G03G 15/045 G03G 15/14-15/16 103 G03G 21 / 00 345-352 G03G 21/06-21/08 G03G 21/16-21/18

Claims (4)

(57) [Claims] 1. An image carrier for forming a transfer image on a recording medium, a process cartridge provided with at least the image carrier and configured to be detachable from an image forming apparatus main body, and an image provided on the process cartridge. The image carrier is opened to open the image carrier when attached to the main body of the forming apparatus, and is closed and closed when taken out of the main body of the image forming apparatus, and is provided separately from the carrier cover. When the carrier cover is opened, the rotation is transmitted, and the recording medium after the image transfer is pressed against the image carrier to separate from the image carrier,
An image forming apparatus, comprising: a separation claw provided on the process cartridge for transmitting the rotation of the cover when the cover is closed and separating the cover from the image carrier. 2. The image forming apparatus according to claim 1, wherein, when the carrier cover is closed, the separation claw is covered by the carrier cover. 3. The process cartridge according to claim 1, wherein the process cartridge is provided with a spur for assisting conveyance of a recording medium, and the spur is covered with the carrier cover when the carrier cover is closed. Image forming device. 4. An image forming apparatus which is detachably attached to an image forming apparatus main body.
And Image carrier for forming an image transferred to a recording medium, and image formation
Open to open the image carrier when attached to the device body
When it is taken out of the image forming apparatus main body, it is closed and the image is closed.
Carrier cover for covering the carrier, and separate from the carrier cover
And the rotation is transmitted when the carrier cover is opened.
Then, the recording medium after the image transfer by pressing against the image carrier is
While separating from the image carrier, close the carrier cover
When it is turned, the rotation is transmitted and it is separated from the image carrier.
A process cartridge provided with a separation claw.