JP2007025346A - Process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the strength of a handle of a process cartridge and the visibility of the handle, and to improve assemblability by preventing flaws and dents to a drum during assembling. <P>SOLUTION: A cleaning frame body 61 is provided with a projection 61a which becomes a core of a handle member projected from a surface of a drum 1, and the handle member in a different color of the cleaning frame body 51 is covered from above. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a process cartridge that can be attached to and detached from an electrophotographic image forming apparatus.

  Here, the electrophotographic image forming apparatus forms an image on a recording medium (for example, recording paper, OHP sheet, etc.) using an electrophotographic image forming system. Examples of the electrophotographic image forming apparatus include, for example, an electrophotographic copying machine, an electrophotographic printer (for example, a laser printer, an LED printer, etc.), a facsimile apparatus, a word processor, and a complex machine thereof (multifunction printer, etc.).

  A process cartridge (hereinafter referred to as a cartridge) refers to a cartridge in which at least developing means (developing member) and an electrophotographic photosensitive drum are integrated into a cartridge so as to be detachable from the main body of the electrophotographic image forming apparatus.

  2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus (hereinafter referred to as “image forming apparatus”), an electrostatic latent image formed on an electrophotographic photosensitive drum (hereinafter referred to as “photosensitive drum”) is developed with a developer by a developing device. Develop using.

  Further, in an image forming apparatus employing a process cartridge, the operator can perform maintenance of the apparatus himself, and this cartridge system can greatly improve operability.

  In such a process cartridge, the photosensitive drum is provided with flange members at both ends, and a shaft member penetrating the photosensitive drum via the flange member is attached. The shaft member is connected to the process cartridge via the bearing member. It is positioned so as to be rotatable on the frame.

Here, a member having a handle of a process cartridge has been devised as a member for restricting the bearing member from coming off the frame. (For example, see Patent Document 1)
JP 2001-166668 A (page 13, FIG. 6)

  The present invention is a further development of the aforementioned prior art.

  An object of the present invention is to provide a process cartridge having improved assemblability, increased strength of an operation portion, and improved operability.

  To achieve the above object, according to a first aspect of the present invention, there is provided a process cartridge having at least an electrophotographic photosensitive drum and a frame for supporting the electrophotographic photosensitive drum, which is detachable from the image forming apparatus. The frame has openings for transferring the toner on the photosensitive drum, and both ends of the opening of the frame have protrusions protruding from the surface of the electrophotographic photosensitive drum, and cover members covering the protrusions are provided. It is characterized by having. Furthermore, in the process cartridge, the cover member has a color different from that of the frame body that supports the electrophotographic photosensitive drum.

  As described above, according to the present invention, it is possible to provide a process cartridge with improved assemblability, increased strength of the operation section, and improved operability.

  The best mode for carrying out the present invention will be exemplarily described below with reference to the drawings. However, the material, shape, relative arrangement, and the like of the component parts described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. Further, the materials, shapes, etc. of the members once described in the following description are the same as those in the first description unless otherwise described.

  A process cartridge and an image forming apparatus according to the present embodiment will be described with reference to FIGS.

[Overall Description of Image Forming Apparatus]
First, the overall configuration of the color image forming apparatus will be described with reference to FIG. FIG. 2 is a schematic cross-sectional view of a color laser printer which is an embodiment of an image forming apparatus using the electrophotographic process according to the present embodiment.

  As shown in FIG. 2, a color laser printer (hereinafter referred to as “printer”) 100 is a photoreceptor that rotates at a constant speed for each color of yellow (Y), magenta (M), cyan (C), and black (K). The image forming unit having the process cartridge 7 (7Y, 7M, 7C, 7K) having the drum 1 (1Y, 1M, 1C, 1K) and the recording medium P fed from the feeding unit are developed by the image forming unit. A transfer unit that multiplex-transfers the image, a fixing unit that fixes the image on the recording medium P to which the color image has been transferred, and a discharge unit that discharges the recording medium P to the upper surface of the apparatus. The four color process cartridges 7Y, 7M, 7C, and 7K are configured to be detachable from the printer main body 100 individually.

  A charging roller 2 (2Y, 2M, 2C, 2K) serving as a charging member that uniformly charges the surface of the photosensitive drum 1 in order according to the rotation direction, and a laser beam based on image information. And a scanner unit 3 (3Y, 3M, 3C, 3K) for forming an electrostatic latent image on the photosensitive drum 1 charged by the charging roller 2. Further, it has a developing unit 4 (4Y, 4M, 4C, 4K) for developing the latent image. And it has the transfer roller 12 (12Y, 12M, 12C, 12K) which transfers the developer image on each photoconductive drum 1 to the recording medium P by the transfer part T. Further, a cleaning unit 6 (6Y, 6M, 6C, 6K) having a cleaning blade 60 for removing the developer remaining on the surface of the photosensitive drum 1 after the transfer is disposed. The transfer roller 12 is provided in the image forming apparatus main body A. In addition, the image forming apparatus main body A includes an electrostatic conveyance belt 5 that electrostatically attracts and conveys the recording medium P.

The recording medium P to which the developer image has been transferred is fixed with the developer image in the fixing device 8. Then, the paper is discharged to the discharge tray 26 on the upper surface of the apparatus by the discharge roller pair 25.
The cartridge 7 includes the above-described photosensitive drum 1, charging member 2, developing unit 4, and cleaning unit 6. Further, the printer 100 has an open / close cover 11 (FIG. 3) integrated with the electrostatic conveyance belt 5. Then, the cartridge 7 is attached to and detached from the printer 100 with the photosensitive drum 1 facing forward with the opening / closing cover 11 opened.

  Hereinafter, the photosensitive drum 1 will be described in detail.

  The photoconductor drum 1 is configured by applying an organic photoconductive layer (OPC photoconductor) to an outer peripheral surface of an aluminum cylinder having a diameter of 24 mm, for example. The photosensitive drum 1 is rotatably supported at both ends by a support member, and is driven to rotate counterclockwise by transmitting a driving force from a driving motor (not shown) to one end. The

  As the charging device 2, a conductive charging roller 2 formed in a roller shape is used as a charging member using a contact charging method. The charging roller 2 is brought into contact with the surface of the photosensitive drum 1 and a charging bias voltage is applied to the charging roller 2 to uniformly charge the surface of the photosensitive drum 1.

  A scanner unit 3 as exposure means is arranged in a substantially horizontal direction of the photosensitive drum 1, and a polygon mirror in which image light corresponding to an image signal is rotated at a high speed by a scanner motor (not shown) by a laser diode (not shown). 9 (9Y, 9M, 9C, 9K). The image light reflected by the polygon mirror 9 selectively exposes the surface of the charged photosensitive drum 1 through the imaging lens 10 (10Y, 10M, 10C, 10K) to form an electrostatic latent image. It is composed.

  The developing unit 4 includes a toner container 41 (41Y, 41M, 41C, 41K) as a developing container as shown in FIG. 4 storing toners of yellow, magenta, cyan, and black, respectively. The toner inside is fed to the toner supply roller 43 by the toner transport mechanism 42. Thereafter, toner is applied to the outer periphery of the developing roller 40 that rotates clockwise as shown in the figure by the toner supply roller 43 that rotates clockwise and the developing blade 44 that is pressed against the outer periphery of the developing roller 40 that serves as a developer carrier. A charge is imparted to. Then, by applying a developing bias to the developing roller 40 facing the photosensitive drum 1 on which the electrostatic latent image is formed, toner development is performed on the photosensitive drum 1 in accordance with the electrostatic latent image. .

  An electrostatic conveyance belt 5 that circulates and moves so as to face and contact all the photosensitive drums 1Y, 1M, 1C, and 1K is disposed. The electrostatic conveyance belt 5 is formed of a film-like member having a predetermined volume specific resistance. The electrostatic conveyance belt 5 is supported by rollers in four directions in the vertical direction, and circulates and moves so that the recording medium P is electrostatically attracted to the outer peripheral surface on the left side in the drawing to bring the recording medium P into contact with the photosensitive drum 1. . As a result, the recording medium P is transported to the transfer position by the electrostatic transport belt 5 and the toner image on the photosensitive drum 1 is transferred.

  The transfer roller 12 (12Y, 12M, 12C, 12K) is arranged in parallel at a position in contact with the inside of the electrostatic conveyance belt 5 and facing the four photosensitive drums 1Y, 1M, 1C, 1K. A positive charge is applied from the transfer roller 12 to the recording medium P via the electrostatic conveyance belt 5, and the electric field generated by the charge causes the recording medium P in contact with the photosensitive drum 1 to be moved onto the photosensitive drum 1. A negative toner image is transferred.

  The feeding unit 16 feeds the recording medium P to the image forming unit, and a plurality of recording media P are stored in the feeding cassette 17. At the time of image formation, the feeding roller 18 (half-moon roller) and the registration roller pair 21 are driven and rotated according to the image forming operation to separate and feed the recording media P in the feeding cassette 17 one by one. The leading end abuts against the registration roller pair 21 and temporarily stops. After forming a loop, the rotation of the electrostatic conveyance belt 5 and the image writing position are synchronized, and the pair is fed to the electrostatic conveyance belt 5 by the registration roller pair 21. Go.

  The fixing device 8 fixes the toner images of a plurality of colors transferred to the recording medium P, and a heating roller 23 that rotates, and a pressure roller 24 that presses against the heating roller 23 and applies heat and pressure to the recording medium P. Consists of. That is, the recording medium P to which the toner image on the photosensitive drum 1 is transferred is conveyed by the heating roller 23 and the pressure roller 24 and is given heat and pressure when passing through the fixing device 8. As a result, toner images of a plurality of colors are fixed on the surface of the recording medium P.

  As an image forming operation, the process cartridge 7 is sequentially driven in accordance with the print timing, and the photosensitive drum 1 is driven to rotate counterclockwise in accordance with the drive. Then, the scanner units 3 corresponding to the respective process cartridges 7 are sequentially driven. By this driving, the charging roller 2 imparts a uniform charge to the circumferential surface of the photosensitive drum 1, and the scanner unit 3 exposes the circumferential surface of the photosensitive drum 1 according to the image signal to perform photosensitive drum 1. An electrostatic latent image is formed on the peripheral surface. The developing roller 40 in the developing device 4 forms (develops) a toner image on the circumferential surface of the photosensitive drum 1 by transferring the toner to the low potential portion of the electrostatic latent image.

  At the timing when the leading edge of the toner image on the circumferential surface of the most upstream photosensitive drum 1 (photosensitive drum 1Y in the drawing) is rotationally conveyed to the opposite point to the electrostatic conveyance belt 5, the recording medium P is located at the opposite point. The registration roller pair 21 starts to rotate so that the printing start positions coincide with each other to feed the recording medium P to the electrostatic conveyance belt 5.

  The recording medium P is pressed against the outer periphery of the electrostatic conveyance belt 5 so as to be sandwiched between the electrostatic adsorption roller 22 and the electrostatic conveyance belt 5, and a voltage is applied between the electrostatic conveyance belt 5 and the electrostatic adsorption roller 22. Is applied to induce a charge on the recording medium P, which is a dielectric, and the dielectric layer of the electrostatic conveyance belt 5, and the recording medium P is electrostatically attracted to the outer periphery of the electrostatic conveyance belt 5. Yes. As a result, the recording medium P is stably adsorbed to the electrostatic conveyance belt 5 and conveyed to the most downstream transfer unit. While being conveyed in this manner, the toner image on each photosensitive drum 1 is sequentially transferred to the recording medium P by an electric field formed between each photosensitive drum 1 and the transfer roller 12.

  The recording medium P to which the four color toner images are transferred is separated from the electrostatic conveyance belt 5 by the curvature of the belt driving roller 14 and is carried into the fixing device 8. After the toner image is thermally fixed by the fixing device 8, the recording medium P is discharged out of the main body by the discharge roller pair 25 with the image surface facing down from the discharge tray 26.

[Removal of process cartridge]
Next, a method for attaching and detaching the cartridge 7 to and from the image forming apparatus 100 will be described with reference to FIG.

  The opening / closing cover 11 of the image forming apparatus 100 has a rotation center on the lower front side of the image forming apparatus 100. The electrostatic cover belt 5 is provided on the opening / closing cover 11. Therefore, when the opening / closing cover 11 is opened, the operator can access the cartridges 7Y, 7M, 7C, and 7K. The cartridge 7 is configured to be inserted and removed in the horizontal direction when the open / close cover 11 of the image forming apparatus 100 is opened.

[Process cartridge configuration]
Next, the configuration of the cartridge 7 will be described with reference to FIGS. 4 is a main cross section of the cartridge 7 containing the developer t, and FIG. 5 is a perspective view thereof. However, FIG. 5 illustrates a state in which the developing unit 4 and the cleaning unit 6 are disassembled.

  As shown in FIG. 3, the cartridge 7 includes a drum-shaped electrophotographic photosensitive member, that is, an electrophotographic photosensitive drum body 1, a cleaning unit 6 including a charging roller 2 and a cleaning blade 60, and an electrostatic on the photosensitive drum 1. The developing unit 4 has a developing roller 40 for developing the latent image.

  The photosensitive drum 1 is rotatably attached to the cleaning unit 6 via a bearing member (cartridge positioning member) 31. A charging roller 2 for uniformly charging the surface of the photosensitive drum 1 and a cleaning blade 60 for removing the developer remaining on the photosensitive drum 1 are disposed on the peripheral surface of the photosensitive drum 1. ing.

  The developer removed from the surface of the photosensitive drum 1 by the cleaning blade 60 is sequentially sent to a waste developer chamber 63 provided behind the drum unit frame 61 by the developer feeding mechanism 62.

  The photosensitive drum 1 is rotated counterclockwise according to the image forming operation by receiving the driving force of a driving motor (not shown) provided in the image forming apparatus main body A.

  The developing unit 4 includes a developing roller 40 that rotates in the direction of the arrow Y in contact with the photosensitive drum 1, a developer storage portion 41 that stores a developer, and a developing container 45. The developing roller 40 is rotatably supported by the developing container 45 via developing bearings 47 and 48. Further, on the peripheral surface of the developing roller 40, a developer supply roller 43 and a developing blade 44 that are in contact with the developing roller 40 and rotate (in the direction of arrow Z) are respectively disposed. Further, a developer transport mechanism 42 for stirring the developer stored in the developer storage section 41 and transporting the developer to the developer supply roller 43 is provided.

  As shown in FIG. 5, the developing unit 4 has the entire developing unit 4 cleaned by a pin 50 around a support hole 49 provided in each of developing bearings 47 and 48 attached to both ends of the developing unit 4. 6 is swingably supported.

  When the cartridge 7 is a single unit (not attached to the apparatus main body A), a pressure spring is applied so that the developing roller 40 is urged toward the photosensitive drum 1 by a rotational moment about the support shaft 50. The developing unit 4 is always urged by 64.

  During development, the developer agitation member 42 conveys the stored developer to the developer supply roller 43. Then, the rotating developer supply roller 43 (in the arrow Z direction) supplies the developer to the developing roller 40 by rubbing against the rotating developing roller 40 (in the arrow Y direction). Then, the developer is carried on the peripheral surface of the developing roller 40. The developer carried on the developing roller 40 reaches the developing blade 44 as the developing roller 40 rotates. Then, the developing blade 44 imparts a charge to the developer. As a result, a predetermined developer thin layer is formed on the peripheral surface of the developing roller 40, and the developer is conveyed to the developing unit where the photosensitive drum 1 and the developing roller 40 are in contact with each other. In the developing unit, a developer is formed on the surface of the photosensitive drum 1 by a DC developing bias applied to the developing roller 40 from a power source (not shown) of the image forming apparatus 100 via a developing / supply electrical contact (not shown). The latent image is developed by adhering to the electrostatic latent image.

  The developer remaining on the surface of the developing roller 40 without contributing to the development is returned to the developing device as the developing roller 40 rotates. Then, it is peeled off and collected from the developing roller 40 at the rubbing portion with the developer supply roller 43. The collected developer is stirred and mixed with the remaining developer by the developer stirring mechanism 42.

[Photosensitive drum support structure]
Next, the structure for supporting the photosensitive drum 1 of the process cartridge 7 will be described in detail with reference to FIGS. In the following description, a and b at the end of the symbol may be omitted in the case of the same configuration on the left and right.

  FIG. 6 is a front view of the support structure of the photosensitive drum in the embodiment to which the present invention is applied, and FIG. 7 is a side view of the periphery of the bearing member and the main body positioning portion in the embodiment to which the present invention is applied.

  As shown in FIG. 6, the photosensitive drum 1 has flanges 200 (200a, 200b) attached to both ends of an aluminum cylindrical member 1a having a photosensitive layer formed on the peripheral surface thereof by adhesion or caulking. A shaft 201 is fitted in the center holes of the flanges 200a and 200b. The shaft 201 is a penetrating shaft, and one end and the other end protrude outward from the photosensitive drum 1 through the aluminum cylindrical member 1a. The shaft 201 is stopped from moving in the rotational direction and the axial direction so as not to slide with the flanges 200a and 200b (not shown). The shaft 201 is a conductive metal rod.

  In the photosensitive drum 1, the outer circumference of the shaft 201 is fitted into the inner circumference of the bearing members 31a and 31b, and the outer circumference of the bearing members 31a and 31b is fitted into the bearing mounting portion 231 which is a recess provided in the cleaning frame 61. . As a result, the photosensitive drum 1 is positioned so as to be rotatable with respect to the cleaning frame 61. As the bearing member 31, for example, a sliding bearing such as a ball bearing or a sintered material can be used.

  Further, in order to prevent the bearing member 31 from falling off the bearing mounting portion 231, the bearing cover member 203 (203 a, 203 b) is attached to the cleaning frame 61 so as to cover the outer periphery and the outer side surface of the bearing member 31 a, b. It is fixed. Here, the bearing cover member 203 and the bearing mounting portion 231 are notched so that a part of the outer peripheral surface of the bearing member 31 is exposed.

  When the process cartridge 7 is mounted on the image forming apparatus main body A, the photosensitive drum 1 is supported on the image forming apparatus main body A by the cleaning frame 61 and the bearing members 31a and 31b with a part of the outer peripheral surface exposed. The exposed portion is directly engaged with the main body positioning portion 102 (102a, 102b). The main body positioning unit 102 is directly provided on the sheet metal frame 101 of the image forming apparatus main body A. Therefore, when the process cartridge 7 is mounted on the image forming apparatus main body A, the process cartridge 7 is positioned with respect to the image forming apparatus main body A with the photosensitive drum 1 as the center.

  Thus, the positioning accuracy of the photosensitive drum 1 with respect to the image forming apparatus main body A is further improved by directly positioning the bearing member 31 supporting the shaft 201 of the photosensitive drum 1 with respect to the main body positioning portion 96. To do.

  Further, the cartridge pressing lever 204 of the image forming apparatus main body A presses the cartridge pressing portion 232 that is the outer peripheral surface of the bearing mounting portion 231 of the cleaning frame body 61 in which the bearing member 31 is fitted, whereby the process cartridge 7 is pressed. The image forming apparatus main body A can be securely held at the image forming position.

[Process cartridge handle configuration]
Next, the handle structure of the cartridge according to the present invention will be described in detail with reference to FIGS.

  Here, FIG. 1 is a perspective view of the periphery of the handle of the process cartridge in the embodiment to which the present invention is applied, and FIG. 8 is an exploded view of the periphery of the handle according to the embodiment of the present invention in the embodiment to which the present invention is applied. It is a perspective view.

  As shown in FIG. 8, arc-shaped ribs 232 are provided around recesses (not shown) that receive bearings 31 provided at one end and the other end of the cleaning frame 61 in the longitudinal direction. A protrusion 61 a that is a handle core adjacent to the protrusion 61 is provided so as to protrude from the cleaning frame 61.

  1 and 8 show only one end.

  Further, the protrusion 61a has a thick base portion close to the cleaning frame 61 in order to give strength.

  By providing the protrusion 61a on the cleaning frame 61, the drum surface is exposed during handling in a state before the drum shutter is attached at the time of assembling the process cartridge. There is sex. In the present invention, since the protrusions 61a provided on the cleaning frame 61 protrude more than the surface of the drum 1, it is possible to prevent the drum 1 from inadvertently coming into contact with somewhere, and to prevent scratches and dents. .

  Further, the above-described bearing cover member 203 (203a, 203b) is fixed to the cleaning frame body 61 so as to cover the outer periphery and the outer side surface of the bearing members 31a, 31b and to cover the protruding portion 61a of the cleaning frame body 61. Yes. The bearing cover member 203 is provided with a protruding portion 203b1 that serves as a handle when the process cartridge is operated. By providing the handle portion 203b1 so as to cover the projection 61a of the cleaning frame body, the strength of the handle portion 203b1 is increased compared to when a bearing cover member having a handle portion is attached to a cleaning frame body without a projection portion. (It is possible to reduce the tilt of the process cartridge in the longitudinal direction when a force is applied).

  The bearing cover member 203 (203a, 203b) is fixed to the cleaning frame 61 by a screw as shown in the figure, and an adhesive is applied to the joint surface between the cleaning frame and the bearing cover member 203 (203a, 203b). You may use the method of adhere | attaching by inject | pouring.

  When bonding is used, grooves (not shown) having a width of 1 mm or less and a depth of 1 mm or less are provided in the protrusions 61 a of the cleaning frame body 61 to facilitate the flow of the adhesive. The bearing cover member 203 (203a, 203b) is provided with a hole for injecting an adhesive.

  The bearing cover member 203 (203a, 203b) has a different color from the cleaning frame 61 so that the user can easily recognize that this portion is a handle portion for handling. For example, the cleaning frame 61 is black, and the bearing cover members 203 (203a, 203b) are light blue.

  As shown in FIG. 1, even when viewed from the inside, the bearing cover member 203 (203a, 203b) covers the protrusion 61a of the cleaning frame 61 and protrudes larger than the protrusion 61a. The color of (203a, 203b) can be recognized, and the user can easily recognize the operation unit.

It is a perspective view of the handle periphery which concerns on embodiment of this invention. 1 is a schematic cross-sectional view of a color laser printer which is an embodiment of an image forming apparatus using an electrophotographic process. 1 is a schematic cross-sectional view of a color laser printer which is an embodiment of an image forming apparatus using an electrophotographic process. It is sectional drawing which shows schematic structure of a process cartridge. It is a disassembled perspective view which shows schematic structure of a process cartridge. It is a front view which shows the support structure of the photosensitive drum which concerns on embodiment of this invention. It is a side view which shows the bearing member and main body positioning part of the process cartridge which concern on embodiment of this invention. It is a disassembled perspective view of the handle periphery which concerns on embodiment of this invention.

Explanation of symbols

1 Photosensitive drum 2 Charging roller (charging member)
DESCRIPTION OF SYMBOLS 3 Scanner unit 4 Developing unit 5 Electrostatic conveyance belt 6 Cleaning unit 7 Process cartridge 8 Fixing device 9 Polygon mirror 10 Imaging lens 11 Opening / closing cover 12 Transfer roller 13 Drive roller 14 Drive roller 16 Tension roller 17 Feed cassette 18 Feed roller DESCRIPTION OF SYMBOLS 19 Separation pad 21 Registration roller pair 22 Electrostatic adsorption roller 23 Heating roller 24 Pressure roller 25 Discharge roller pair 26 Discharge tray 30 Driving force receiving part 31 Bearing member 40 Developing roller (developing member)
DESCRIPTION OF SYMBOLS 41 Developer accommodating part 42 Conveying member 43 Supply roller 44 Developing blade 45 Developing frame body 46 Helical gear 47 Developing bearing 49 Support hole 50 Support shaft 55 Memory unit 56 Communication unit 60 Cleaning blade 61 Cleaning frame body 62 Developer feeding mechanism 63 Accommodating chamber 64 Pressurizing spring 81 Cartridge rotation restricting portion 91 Charging electrical contact 92 Developing / supply electrical contact 93 Developing blade electrical contact 100 Electrophotographic image forming apparatus (printer)
DESCRIPTION OF SYMBOLS 101 Main body frame 102 Main body positioning part 200 Flange 201 Drum shaft 203 Bearing cover 204 Cartridge pressing lever A Electrophotographic image forming apparatus main body t Developer

Claims (3)

At least a process cartridge that can be attached to and detached from an image forming apparatus having an electrophotographic photosensitive drum and a frame that supports the electrophotographic photosensitive drum.
The frame has openings for transferring the toner on the photosensitive drum, both ends of the opening of the frame have protrusions protruding from the surface of the electrophotographic photosensitive drum, and cover members that cover the protrusions. Process cartridge characterized by that.   2. The process cartridge according to claim 1, wherein the cover member prevents the bearing member of the electrophotographic photosensitive drum from coming off.   3. The process cartridge according to claim 1, wherein the cover member has a color different from that of the frame that supports the electrophotographic photosensitive drum.

Images