JP2003076249A - Process cartridge and electrophotographic image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate an image defect and a decrease in picture quality due to rotational unevenness and vibration of a photoreceptor drum by increasing the rigidity of a fitting part supporting the photoreceptor drum rotatably and to actualize both lower costs by a decrease in man-hour for assembly and smaller size. SOLUTION: A process cartridge has drum bearings 24 and a drum shaft 25 which rotatably support the photoreceptor drum 7 at both ends along the length, a drum frame body 19 which holds the photoreceptor drum 7, and side coves 22 and 23 which couples the drum frame body 19 (photoreceptor unit 21) and a developing device unit 20; and the drum bearings 24 and drum shaft 25 which rotatably support the photoreceptor drum 7 and put between the drum frame body 19 and side covers 22 and 23, which are fixed to the drum frame body 19 with screws 28, etc., to fix the drum bearings 24 and drum shaft 25 at the same time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process cartridge and an electrophotographic image forming apparatus used for forming an image in a printer, a copying machine or the like.

Here, the electrophotographic image forming apparatus is an apparatus for forming an image on a recording medium by using an electrophotographic image forming process. For example, an electrophotographic copying machine, an electrophotographic printer (for example, laser beam printer, LED printers, etc.), electrophotographic facsimile machines, electrophotographic word processors, etc.

[0003]

2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus using an electrophotographic image forming process, an electrophotographic photosensitive drum and process means acting on the electrophotographic photosensitive drum are integrally made into a cartridge, and this cartridge is used. A process cartridge system is employed in which is attached detachably to the main body of the electrophotographic image forming apparatus. In such a process cartridge system, an electrophotographic photosensitive drum and at least one of a charging unit, a developing unit and a cleaning unit or at least a developing unit are integrally formed into a cartridge, and the cartridge is used as a main body of the electrophotographic image forming apparatus. There are things that can be attached and detached.

According to this type of process cartridge system, the maintenance of the apparatus can be performed by the user himself without resorting to a serviceman, so that the operability can be markedly improved. Therefore, this process cartridge system is widely used in electrophotographic image forming apparatuses.

Further, in this type of process cartridge, a photoconductor unit in which an electrophotographic photoconductor drum, cleaning means, and the like are integrally united, and a developing device unit in which a developing sleeve, a toner container, and the like are unitized are combined. It is known that an integrated cartridge is used. In this process cartridge, an electrophotographic photosensitive drum, a charging unit and a cleaning unit are attached to a drum frame as a photosensitive unit, and in particular, the electrophotographic photosensitive drum rotatably supports both ends thereof. It is attached to a supporting member provided with a bearing and the like and then fixed to the drum frame by screws and the like. Also,
As the developing device unit, in addition to the developing sleeve and the toner accommodating container, a developing blade, a toner conveying means and the like are further incorporated. Then, both side surfaces of the photoconductor unit and the developing device unit are joined by side covers or the like and fixed by screws to be integrated to form a process cartridge.

[0006]

However, in the structure of the process cartridge as described above, the following problems may occur.

(1) When the electrophotographic photosensitive drum is attached to the drum frame, if the rigidity of the mounting portion of the drum frame is low, the bearing and the shaft may tilt, resulting in uneven rotation of the electrophotographic photosensitive drum. This causes vibrations and deteriorates the image quality.

(2) A fixing portion for fixing the electrophotographic photosensitive drum to the drum frame (a screw hole for screwing a support member having a bearing or the like to the drum frame) and the both units are combined. Since a fixing portion for fixing the side cover to the drum frame (such as a screw hole for fixing a screw) is required, it becomes an obstacle to downsizing, and at the same time, an increase in the number of assembling steps leads to an increase in cost.

Therefore, the present invention has been made in view of the above-mentioned unsolved problems of the prior art, and the rigidity of the mounting portion for rotatably supporting the electrophotographic photosensitive drum is increased to increase the rigidity of the photosensitive drum. An object of the present invention is to provide a process cartridge and an electrophotographic image forming apparatus that eliminate image defects and image quality deterioration due to rotation unevenness and vibration, reduce the assembly man-hours, and achieve cost reduction and downsizing. It is what

[0010]

In order to achieve the above object, the process cartridge of the present invention is an electrophotographic photosensitive drum and the electrophotographic photosensitive drum, wherein the process cartridge is detachable from the main body of the electrophotographic image forming apparatus. A developing device for developing the electrostatic latent image formed on the surface of the electrophotographic photosensitive drum with a developer, and a support provided at both ends in the longitudinal direction of the electrophotographic photosensitive drum and rotatably supporting the electrophotographic photosensitive drum. A member, a drum frame to which the electrophotographic photosensitive drum is attached, and a coupling frame that is disposed at both ends in the longitudinal direction of the electrophotographic photosensitive drum and that couples the drum frame and the developing device, The support member is sandwiched between the drum frame and the coupling frame and supported.

In the process cartridge of the present invention,
It is preferable that the coupling frame is fixed to the drum frame with screws.

In the process cartridge of the present invention,
It is preferable that the coupling frame and the support member are fixed to the drum frame body by being screwed together.

In the process cartridge of the present invention,
It is preferable that the coupling frame is fixed to the drum frame by a snap fit.

The electrophotographic image forming apparatus of the present invention is
An electrophotographic image forming apparatus for forming an image on a recording medium is characterized in that the above-mentioned process cartridge is detachably mounted.

Further, the electrophotographic image forming apparatus of the present invention is an electrophotographic image forming apparatus for forming an image on a recording medium, in which the electrophotographic photosensitive drum and the electrostatic formed on the electrophotographic photosensitive drum. A developing device for developing a latent image with a developer, a supporting member provided at both ends in the longitudinal direction of the electrophotographic photosensitive drum, and rotatably supporting the electrophotographic photosensitive drum, and the electrophotographic The electrophotographic photosensitive drum has a drum frame to which a photoconductor drum is attached, and coupling frames that are arranged at both ends in the longitudinal direction of the electrophotographic photoconductor drum and couple the drum frame and the developing device to each other. It is characterized in that it is supported by being sandwiched between a drum frame and the coupling frame.

In the electrophotographic image forming apparatus of the present invention,
It is preferable that the coupling frame is fixed to the drum frame with screws.

In the electrophotographic image forming apparatus of the present invention,
It is preferable that the coupling frame and the support member are fixed to the drum frame body by being screwed together.

In the electrophotographic image forming apparatus of the present invention,
It is preferable that the coupling frame is fixed to the drum frame by a snap fit.

[0019]

According to the process cartridge and the electrophotographic image forming apparatus of the present invention, the rigidity of the bearing for rotatably supporting the electrophotographic photosensitive drum and the mounting portion of the shaft member can be increased to prevent the shaft from falling. It is possible to reduce uneven density and uneven pitch due to uneven rotation and vibration of the photosensitive drum. Also, by reducing the number of screws for mounting and fixing, it is possible to reduce the cost by assembling man-hours, and it is possible to reduce the space for fixing screws for mounting and fixing. It is possible to reduce the size of the device and the device and improve the degree of freedom in design.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a process cartridge and an electrophotographic image forming apparatus according to the present invention will be described below with reference to the drawings.

First, FIG. 1 and FIG. 2 show an embodiment of an electrophotographic image forming apparatus constructed according to the present invention.
Will be described with reference to.

FIG. 1 is a schematic configuration diagram showing a configuration of an electrophotographic image forming apparatus according to the present invention, and FIG. 2 is a vertical sectional view of a process cartridge detachable from the electrophotographic image forming apparatus according to the present invention. is there. The electrophotographic image forming apparatus uses an electrophotographic image forming process to print a recording sheet,
An apparatus for forming an image on a recording medium such as a P-sheet, cloth, etc., such as an electrophotographic copying machine, an electrophotographic printer (eg, LED printer, laser beam printer, etc.), an electrophotographic facsimile machine, an electrophotographic word processor, etc. However, in the present embodiment, an electrophotographic laser beam printer will be described as an example.

Electrophotographic image forming apparatus (in this embodiment,
The laser beam printer A has an electrophotographic photosensitive drum (hereinafter, also simply referred to as a photosensitive drum) 7. The photosensitive drum 7 is charged by a charging roller 8 which is a charging unit, and then a laser diode and a polygon. mirror,
A latent image corresponding to the image information is formed on the photosensitive drum 7 by irradiating the laser beam light according to the image information from the optical unit 1 having a lens and a reflection mirror. The latent image is developed by a developing device using a developer (hereinafter, also simply referred to as toner) to be a visible image, that is, a toner image.

In the developing device, a developing sleeve 10 which is a developer carrying member for sending toner to the photosensitive drum 7, a magnet roller (fixed magnet) 11 incorporated in the developing sleeve 10, and a surface of the developing sleeve 10 are attached. Developing blade 12 which is a regulating member for regulating the amount of toner
And a developing frame 1 held by the developing frame 13 and holding the developing sleeve 10 and the developing blade 12.
Reference numeral 3 forms a developing device unit 20 in combination with a toner storage container 14 for storing toner.

Toner container 14a of toner container 14
The toner is agitated and the toner is applied to the developing frame body 13.
A toner feeding member 15 for feeding the toner to the developing chamber 13a therein is provided, and the developing sleeve 13 is provided in the developing chamber 13a.
A rotatable toner stirring member 16 is provided in the vicinity of 2, and circulates the toner in the developing chamber 13a. With this configuration, the toner accommodated in the toner accommodating portion 14a is stored in the developing chamber 13a by the rotation of the toner feeding member 15.
To the toner stirring member 16 in the developing chamber 13a.
The toner is fed to the developing sleeve 10 while being stirred by. The toner has magnetism, and the magnet roller 11
Adheres to the surface of the developing sleeve 10 containing therein. Then, the toner is conveyed by the rotation of the developing sleeve 10, a triboelectric charge is applied by the developing blade 12, a toner layer having a predetermined thickness is formed on the developing sleeve 10, and the toner is conveyed to the developing area of the photosensitive drum 7. To be done. The toner supplied to the developing area is transferred to the latent image on the photoconductor drum 7 to form a toner image on the photoconductor drum 7. The developing sleeve 10 is connected to a developing bias circuit provided in the main body of the electrophotographic image forming apparatus A, and is normally applied with a developing bias voltage in which a DC voltage is superimposed on an AC voltage.

On the other hand, in synchronization with the formation of the toner image, the recording medium 2 set in the paper feed cassette 3a is conveyed to the transfer position by the pickup roller 3b and the conveying roller pairs 3c, 3d and 3e. A transfer roller 4 as a transfer unit is disposed at the transfer position, and a toner image on the photosensitive drum 7 is transferred to the recording medium 2 by applying a voltage.

The recording medium 2 to which the toner image has been transferred is conveyed to the fixing means 5 via the conveyance guide 3f. The fixing unit 5 includes a driving roller 5c and a fixing roller 5b having a heater 5a built therein, and applies heat and pressure to the recording medium 2 passing therethrough to fix the transferred toner image on the recording medium 2.

The recording medium 2 is conveyed by the pair of discharge rollers 3g and 3h, and is discharged to the discharge tray 6 via the reversing path 3i. The discharge tray 6 is provided on the upper surface of the electrophotographic image forming apparatus A. Note that the swingable flapper 3j can be operated to eject the recording medium 2 without passing through the inversion path 3i. In the present embodiment, the conveying means 3 is constituted by the pickup roller 3b, the conveying roller pairs 3c, 3d, 3e, the conveying guide 3f, the discharge roller pairs 3g, 3h and the like.

The photosensitive drum 7 after the toner image is transferred onto the recording medium 2 by the transfer roller 4 is subjected to the next image forming process after removing the toner remaining on the photosensitive drum 7 by the cleaning means 17. It The cleaning unit 17 uses the elastic cleaning blade 17 a provided in contact with the photoconductor drum 7 to remove the photoconductor drum 7.
The upper residual toner is scraped off and collected in the waste toner reservoir 17b.

Next, a process cartridge which can be attached to and detached from the electrophotographic image forming apparatus will be described with reference to FIG. As shown in FIG. 2, the process cartridge B of this embodiment includes a developing device unit 20 and a photoconductor unit 21.
The developing device unit 20 is configured by integrally forming the toner storage container 14 by welding on the developing device frame 13 that holds the developing device such as the developing sleeve 10 and the developing blade 12. The toner storage container 14 has a toner storage portion 14a for storing toner, and a toner supply opening 14b for supplying the toner in the toner storage portion 14a to the developing chamber 13a in the developing frame 13 and storing the toner. A toner feeding member 15 is rotatably supported in the portion 14a. The toner supply opening 14b is sealed by a developer seal (not shown) until the process cartridge B is used, and the developer seal is pulled out by the user when the process cartridge B is first used. Thus, the toner can be supplied.

Further, the cleaning means 17 such as the photosensitive drum 7, the charging roller 8 and the elastic cleaning blade 17a is attached to the drum frame 19 to form an integral photosensitive unit 21.

The photosensitive drum 7 is attached to the drum frame 19 as shown in FIG. That is, gear flanges 7a and 7b are attached to both ends of the photosensitive drum 7, and the gear flange 7a is a drum bearing 24.
Is rotatably supported on the drum shaft 2 by the gear flange 7b.
5, the drum bearing 24 and the drum shaft 25 are respectively held by the side plates 19a and 19b of the drum frame body 19, and the photosensitive drum 7 is connected to the photosensitive body unit 21.
Incorporated into. The gear flange 7a is provided with a rotational driving force from the apparatus main body side by connecting a rotation driving mechanism on the apparatus main body side to the end portion thereof, and the gear on the circumference transmits the driving force to the developing sleeve 10 and the like. In addition, the gears on the circumference of the gear flange 7b serve to transmit the driving force to the transfer roller 4 and the like.

The photoconductor unit 21 thus constructed
The process cartridge B is configured by coupling and integrating the developing device unit 20 and the developing device unit 20.

Next, one embodiment of the structure in which the photoconductor unit 21 and the developing device unit 20 are joined together will be described with reference to FIG.
It will be described with reference to FIGS.

FIG. 4 and FIG. 5 are exploded perspective views of the first embodiment of the process cartridge according to the present invention, and FIG. 6 is a process cartridge of the present embodiment, in which a drum bearing and a drum are provided by a side cover. It is sectional drawing which shows the structure of the attachment part of a shaft to a drum frame.

Photoreceptor unit 21 and developing device unit 2
0 is joined by side covers 22 and 23 as joining frames on both sides in the longitudinal direction. On one side cover 22, the cylindrical portion 2 of the drum bearing 24 that rotatably supports the gear flange 7a of the photosensitive drum 7.
4a, a reference boss 22b that fits into the reference hole 20a of the developing device unit 20 (see FIG. 5), a side plate 19a of the drum frame 19 of the photoconductor unit 21, and the developing device unit 20. Screw fixing portions 2 formed so as to correspond to the screw holes provided on the side surface of the
2c is provided, and the other side cover 23 is provided.
The reference hole 23a for fitting the cylindrical portion 25a of the drum shaft 25 that rotatably supports the gear flange 7b of the photosensitive drum 7, and the reference hole 20b of the developing device unit 20.
(See FIG. 4), a plurality of screws formed so as to correspond to the screw holes provided on the side wall of the developing device unit 20 and the side plate 19b of the drum frame body 19 of the photoconductor unit 21. The fixed portion 23c is provided.

Therefore, the side cover 22 is positioned with respect to the photoconductor unit 21 by fitting the reference hole 22a with the cylindrical portion 24a of the drum bearing 24,
The side cover 22 is fixed by screws 28.
Reference boss 22b and reference hole 20 of the developing device unit 20
It is positioned with respect to the developing device unit 20 by fitting a, and is similarly fixed by the screw 28. On the other hand, the side cover 23 is positioned with respect to the photoconductor unit 21 by fitting the reference hole 23a with the cylindrical portion 25a of the drum shaft 25, and is fixed with the screw 28. The developing device unit 20 is also fixed in the same manner as the opposite side.

As described above, the side cover 22 is positioned by the fitting of the reference hole 22a and the cylindrical portion 24a of the drum bearing 24, and the screw 28 is attached to the drum frame 19.
Fixed by. At this time, as shown in FIG. 6, a hole 24b is formed in the drum bearing 24 so as to avoid the screw fixing portion 22c of the side cover 22, and the side cover 22 is screwed to the drum frame 19 (19a) by a screw 28. When fixed by, the drum bearing 24 is attached to the side cover 22.
And the drum frame 19 (19a). Similarly to the side cover 22, the other side cover 23 is also positioned by the cylindrical portion 25a of the drum shaft 25 and fixed by the screw 28. As shown in FIG. 6, the screw fixing portion 23c of the side cover 23 is provided in the vicinity of the sheet metal portion 25b of the drum shaft 25, and the side cover 23 is fixed to the drum frame 19 (19b) with a screw 28. As a result, the sheet metal portion 25b of the drum shaft 25 is attached to the side cover 23
The drum shaft 25 is also fixed by being sandwiched between the drum frame 19 (19b).

In this embodiment, as described above, the drum bearing 24 and the drum shaft 25, which rotatably support the photosensitive drum 7, are sandwiched and fixed between the drum frame 19 and the side covers 22 and 23, respectively. As compared with the case where the drum bearing or the drum shaft is fixed only to the side wall of the drum frame, the rigidity of the mounting portion of the drum bearing 24 and the drum shaft 25 can be increased, and the fall of the shaft can be prevented. it can. As a result, it is possible to prevent uneven rotation and vibration of the photosensitive drum 7, and it is possible to reduce uneven density and uneven pitch due to uneven rotation and vibration of the photosensitive drum.
The image quality can be improved. Further, since the side covers 22 and 23 as the coupling frame are fixed to the drum frame body 19 with screws, the drum bearing 24 and the drum shaft 25 are fixed at the same time.
It is possible to eliminate the step of individually fixing the drum 4 and the drum shaft 25, and it is possible to reduce the cost. Further, since the number of fixing screws can be reduced, it is possible to reduce the space for fixing the screws, and it is possible to reduce the size of parts and devices and improve the degree of freedom in design.

Next, regarding the second embodiment of the present invention,
This will be described with reference to FIG. FIG. 7 is a cross-sectional view showing a configuration of a drum bearing by a side cover and a mounting portion of the drum shaft to a drum frame in the second embodiment of the present invention. In this embodiment, the schematic configurations of the main body of the electrophotographic image forming apparatus and the process cartridge are the same as those in the first embodiment described above, and thus detailed description thereof will be omitted.

The mounting structure of the drum bearing 24 and the drum shaft 25 to the drum frame 19 by the side covers 22 and 23 as the coupling frame in this embodiment is slightly different from the mounting structure of the first embodiment described above. ,
Other configurations are the same. In this embodiment, a hole 24c for screw insertion is formed in a portion of the drum bearing 24 corresponding to the screw fixing portion 22c of the side cover 22, and the side cover 22 and the drum bearing 24 are screwed to the drum frame 19 (19a). 28, a hole 25c for screw insertion is formed in a portion of the sheet metal portion 25b of the drum shaft 25 corresponding to the screw fixing portion 23c of the side cover 23, and the side cover 23 and the drum shaft 25 are connected to each other. The frame 19 (19b) is screwed together with a screw 28. Also in this embodiment configured as described above, the same effect as that of the first embodiment can be obtained.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 8 is a cross-sectional view showing a configuration of a drum bearing by a side cover and a mounting portion of the drum shaft to a drum frame in the third embodiment of the present invention. Note that, also in this embodiment, the schematic configurations of the image forming apparatus main body and the process cartridge are the same as those of the first embodiment described above.
The detailed description thereof is omitted because it is the same as that of the first embodiment.

In FIG. 8, left and right side covers 32 and 33 are coupling frames for coupling the photoconductor unit and the developing device unit, as in the above-described first embodiment. A reference hole 32a for fitting the cylindrical portion 34a of the drum bearing 34 that rotatably supports the gear flange 7a of the drum 7 and a reference boss (not shown) fitted to the reference hole (not shown) of the developing device unit are provided. Further, it corresponds to a claw engaging hole 37a provided in the side plate 19a of the drum frame 19 of the photoconductor unit 21 and a claw engaging hole (not shown) provided on the side surface of the developing device unit 20, respectively. Is provided with a plurality of snap-fit claws 32c, and the side cover 33 allows the gear flange 7b of the photosensitive drum 7 to rotate. The cylindrical portion 3 of the drum shaft 35 for lifting
Reference hole 33a for fitting 5a, reference boss (not shown) for fitting in the reference hole of the developing device unit, and claw engagement hole 37b provided in side plate 19b of drum frame 19 of photoconductor unit 21. And a plurality of snap-fitting claws 33c formed so as to correspond to the claw engaging holes (not shown) provided on the side surface of the developing device unit 20.

Therefore, the side cover 32 in this embodiment is positioned on the photoconductor unit by fitting the reference hole 32a and the cylindrical portion 34a of the drum bearing 34, and the snap fit claw 32c is attached to the drum frame body 19.
It is fixed by engaging with the claw engaging hole 37a of (19a). The drum bearing 34 is provided with a hole 34b so as to avoid the snap fit claw 32c of the side cover 32. Then, when the side cover 32 is fixed to the drum frame body 19, the drum bearing 34 is sandwiched and fixed between the side cover 32 and the drum frame body 19.

On the other hand, like the side cover 32, the side cover 33 also has the reference hole 33a and the cylindrical portion 3 of the drum shaft 35.
Positioned by 5a, snap fit claw 33c
Is fixed by engaging with the claw engaging hole 37b of the drum frame 19 (19b). Snap fit claw 33
c is provided in the vicinity of the metal plate portion 35b of the drum shaft 35. The sheet metal portion 35b of the drum shaft 35 is designed to be sandwiched between the side cover 33 and the drum frame body 30. By fixing the side cover 33 to the drum frame body 19 (19b), the drum shaft 35 is also supported by the side cover 33. Drum frame 1
It is sandwiched between 9 and fixed.

In this embodiment, since the side cover and the drum frame are fixed by snap fitting, the assembly can be further facilitated. Also, the effect of increasing the rigidity of the drum bearing and the mounting part of the drum shaft is
This is similar to the first and second embodiments described above.

[0047]

As described above, according to the process cartridge and the image forming apparatus of the present invention, the rigidity of the bearing for rotatably supporting the photosensitive drum and the mounting portion of the shaft member can be increased, and It is possible to prevent tilting and reduce uneven density and uneven pitch due to uneven rotation and vibration of the photosensitive drum. Further, by reducing the number of screws for mounting and fixing, it is possible to reduce the cost by assembling man-hours. Further, it is possible to reduce the space for fixing screws and the like for mounting and fixing, and it is possible to reduce the size of parts and devices and improve the degree of freedom in design.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a configuration of an electrophotographic image forming apparatus according to the present invention.

FIG. 2 is a vertical cross-sectional view of a process cartridge detachably mountable to the electrophotographic image forming apparatus according to the present invention.

FIG. 3 is a perspective view of a photoconductor unit in the first embodiment of the process cartridge according to the present invention.

FIG. 4 is an exploded perspective view of the first embodiment of the process cartridge according to the present invention as seen from the left.

FIG. 5 is an exploded perspective view of the first embodiment of the process cartridge according to the present invention as seen from the right.

FIG. 6 is a cross-sectional view showing a configuration of a drum bearing by the side cover and a mounting portion of the drum shaft to the drum frame body in the first embodiment of the process cartridge according to the present invention.

FIG. 7 is a cross-sectional view showing a configuration of a drum bearing by a side cover and a mounting portion of the drum shaft to the drum frame body in the second embodiment of the process cartridge according to the present invention.

FIG. 8 is a cross-sectional view showing a configuration of a drum bearing by a side cover and a mounting portion of the drum shaft to a drum frame in a third embodiment of the process cartridge according to the present invention.

[Explanation of symbols]

A Electrophotographic image forming apparatus B process cartridge 1 Optical means 2 recording media 3 (3a, 3b ...) Conveying means 4 Transfer roller (transfer means) 5 fixing means 6 discharge tray 7 Photosensitive drum (electrophotographic photosensitive drum) 7a, 7b Gear flange 8 Charging roller (charging means) 10 Development sleeve 11 Magnet roller (fixed magnet) 12 Development blade 13 Development frame 13a Development room 14 Toner storage container 14a toner container 14b Toner supply opening 15 Toner feed member 16 Toner stirring member 17 Cleaning means 17a cleaning blade 17b Waste toner storage 19 drum frame 20 Development unit 21 Photoconductor unit 22 Side cover (combined frame) 22a Reference hole 22b Standard boss 22c screw fixing part 23 Side cover (combined frame) 23a Reference hole 23b Reference boss 23c screw fixing part 24 drum bearing 24a cylindrical part 24c (for screw insertion) hole 25 drum shaft 25a cylindrical part 25b Sheet metal part 25c (for screw insertion) hole 28 (for fixing) screw 32 Side cover (combined frame) 32a reference hole 32c snap fit claw 33 Side cover (combined frame) 33a Reference hole 33c snap fit claw 34 drum bearing 34a cylindrical part 35 drum shaft 35a cylindrical part 35b Sheet metal part 37a, 37b Claw engagement hole

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Ryuta Murakami             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F term (reference) 2H035 CA07 CB03 CB04 CD05 CD07                       CD11 CD14 CG03                 2H071 BA05 BA13 BA16 BA29 CA05                       DA08 DA15

Claims (9)

[Claims] 1. A process cartridge attachable to and detachable from a main body of an electrophotographic image forming apparatus, wherein an electrophotographic photosensitive drum and an electrostatic latent image formed on the electrophotographic photosensitive drum are developed by using a developer. A developing device, a support member provided at both ends in the longitudinal direction of the electrophotographic photosensitive drum, and rotatably supporting the electrophotographic photosensitive drum, a drum frame to which the electrophotographic photosensitive drum is attached, The electrophotographic photosensitive drum is provided at both ends in the longitudinal direction, and has a coupling frame that couples the drum frame and the developing device, and the support member is sandwiched between the drum frame and the coupling frame. A process cartridge characterized in that it is supported by the process cartridge. 2. The process cartridge according to claim 1, wherein the coupling frame is fixed to the drum frame with screws. 3. The process cartridge according to claim 1, wherein the coupling frame and the support member are fixed to the drum frame body by being screwed together. 4. The process cartridge according to claim 1, wherein the coupling frame is fixed to the drum frame body by a snap fit. 5. An electrophotographic image forming apparatus for forming an image on a recording medium, wherein the process cartridge according to any one of claims 1 to 4 is detachably mounted. Electrophotographic image forming apparatus. 6. An electrophotographic image forming apparatus for forming an image on a recording medium, wherein an electrophotographic photosensitive drum and an electrostatic latent image formed on the electrophotographic photosensitive drum are developed using a developer. A developing device for supporting the electrophotographic photosensitive drum, the supporting member being provided at both ends in the longitudinal direction of the electrophotographic photosensitive drum, and rotatably supporting the electrophotographic photosensitive drum; and a drum frame to which the electrophotographic photosensitive drum is attached. The electrophotographic photosensitive drum is provided at both ends in the longitudinal direction, and has a coupling frame for coupling the drum frame and the developing device, and the support member is provided between the drum frame and the coupling frame. An electrophotographic image forming apparatus characterized in that it is sandwiched between and supported by. 7. The electrophotographic image forming apparatus according to claim 6, wherein the coupling frame is fixed to the drum frame with screws. 8. The electrophotographic image forming apparatus according to claim 6, wherein the coupling frame and the support member are fixed to the drum frame body by being screwed together. 9. The electrophotographic image forming apparatus according to claim 6, wherein the coupling frame is fixed to the drum frame body by a snap fit.