JPH08305256A - Process cartridge and image forming device - Google Patents

Abstract

PURPOSE: To prevent rattling and strange noises without application of grease by providing an electric contact member for grounding an image carrier to a main body, and forming the electric contact member from a conductive resin. CONSTITUTION: A drum grounding electrode 16 is mounted on one of flanges 8 which are fitted into place at both of the longitudinal ends of a photosensitive drum 1 and which are freely rotatably fitted into a drum shaft 15. Inside the photosensitive drum 1, the drum grounding electrode 16 is joined to the end face of the flange 8, and when a drum gear 9 integrated with one of the flanges 8 is rotated in response to a drive force, the electrode 16 is rotated together with the photosensitive drum 1, with the result that a conductive resin member 20 which the drum grounding electrode 16 has slides against the outer peripheral surface of the drum shaft 15 to serve as a contact. The drum grounding electrode 16 has an arm 16b extending diagonally to the drum shaft 15 from the outer periphery of a disk 16a in contact with the end face of the flange 8, and has the conductive resin member 20 at the end of the arm 16b. The conductive resin member 20 makes contact with the drum shaft 16 at a different position with respect to the direction of the axis of the drum shaft 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member and a process cartridge acting on the electrophotographic photosensitive member, which is integrally formed as a cartridge, and is attachable to and detachable from an image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus using an electrophotographic image forming process, an electrophotographic photosensitive member and process means acting on the electrophotographic photosensitive member are integrally formed into a cartridge, and the cartridge is formed into an image forming apparatus. A process cartridge system that can be attached to and detached from the main body is adopted. According to this 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 image forming apparatuses.

In such a process cartridge, it is necessary to apply a bias voltage to the charging roller which constitutes the charging means and the developing sleeve which constitutes the developing means, and to electrically ground the image carrier. The charging roller, the developing sleeve, the image carrier, and the like are rotated, so that the contact member is brought into contact with the fixed member and slid, and the image forming apparatus main body and the process cartridge are electrically connected via the contact member. I am trying. For example, a metal contact member such as phosphor bronze is joined to the inner circumference of the photosensitive drum in the process cartridge, and the fixed drum shaft that penetrates the photosensitive drum slides between the metal and the drum shaft to the image forming apparatus main body. It is designed to be grounded.

[0004]

SUMMARY OF THE INVENTION The present invention is a further development of the prior art.

Therefore, the present invention is intended to solve the above problems, and an object of the present invention is to maintain good electrical conductivity and to prevent the generation of abnormal noise or noise even without applying grease. An object of the present invention is to provide a process cartridge and an image forming apparatus having a contact member that can be prevented.

[0006]

A first aspect of the present invention is an electrophotographic photosensitive member in a process cartridge detachably mountable to an image forming apparatus main body, process means acting on the electrophotographic photosensitive member, and An electric contact member for grounding the electrophotographic photosensitive member to the main body of the image forming apparatus, wherein the electric contact member is a conductive resin member.

A second aspect of the present invention is the process cartridge according to the first aspect, wherein the electric contact member is in contact with an outer peripheral surface of a shaft supporting the electrophotographic photosensitive member.

A third invention of the present invention is the process cartridge according to the second invention, wherein two or more electric contact members are provided.

A fourth aspect of the present invention is the process cartridge according to the third aspect, wherein the two or more electric contact members are arranged at different positions in the longitudinal direction of the electrophotographic photosensitive member. is there.

A fifth aspect of the present invention is the process cartridge according to the fourth aspect, wherein the electric contact member has two or more protruding portions.

According to a sixth aspect of the present invention, the process cartridge comprises a charging means, a developing means or a cleaning means as the process means, and an electrophotographic photosensitive member, which are integrally formed into a cartridge, and the cartridge is formed into an image forming apparatus main body. The process cartridge according to any one of the first to fifth aspects, wherein the process cartridge is removable.

In a seventh aspect of the present invention, the process cartridge is an image forming apparatus main body in which at least one of charging means, developing means and cleaning means as the process means and an electrophotographic photosensitive member are integrally formed into a cartridge. The process cartridge according to any one of the first to fifth aspects, wherein the process cartridge is removable.

According to an eighth aspect of the present invention, the process cartridge is a cartridge in which at least the developing means as the process means and the electrophotographic photosensitive member are integrally made into a cartridge so as to be attachable to and detachable from the apparatus main body. The process cartridge according to any one of the first to fifth aspects of the invention.

A ninth aspect of the present invention is an electrophotographic photosensitive member,
A process cartridge acting on the electrophotographic photosensitive member and an electric contact member for grounding the electrophotographic photosensitive member to the main body of the image forming apparatus are provided. The electric contact member is a conductive resin member, and the process cartridge is removable. An image forming apparatus comprising: a mounting unit for mounting the recording medium on the recording medium; and a conveying unit that conveys the recording medium.

A tenth aspect of the present invention is characterized in that the electric contact member is in contact with an outer peripheral surface of a shaft fixed to a main body of an image forming apparatus for rotatably supporting the electrophotographic photosensitive member. The image forming apparatus according to the invention.

An eleventh invention of the present invention is the image forming apparatus according to the tenth invention, wherein two or more electric contact members are provided.

The twelfth aspect of the present invention is the image forming apparatus according to the eleventh aspect, wherein the two or more electric contact members are arranged at different positions in the longitudinal direction of the electrophotographic photosensitive member. Is.

A thirteenth invention of the present invention is the image forming apparatus according to the twelfth invention, wherein the electric contact member has two or more protruding portions.

A fourteenth invention of the present invention comprises an image carrier, a process means acting on the image carrier, and an electric contact member for grounding the image carrier to the main body of the image forming apparatus. In the image forming apparatus, the electric contact member is a conductive resin member.

In the above structure, since the electric contact member is made of a conductive resin member, even if the contact member slides on another metal contact without impairing the conduction performance, an abnormal noise is generated.・ No abnormal noise will occur.

Therefore, it is not necessary to apply grease or the like as in the conventional case, so that the workability is improved, and the production line can be easily automated.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a process cartridge and an image forming apparatus according to the present invention will be specifically described with reference to the drawings.

(First Embodiment) FIG. 1 is a sectional view of a process cartridge, FIG. 2 is a schematic diagram of a ground contact of a photosensitive drum, and FIG. 3 is an explanatory view of a conductive resin member of a drum ground electrode. Process cartridge A constituting the image forming unit
Is a drum-shaped electrophotographic photosensitive member (hereinafter referred to as a photosensitive drum) 1 having a photosensitive layer, and its surface is uniformly charged by applying a voltage to a charging roller 2 serving as a charging unit. An optical image (not shown) is exposed on the photosensitive drum 1 through the exposure optical path space 9 to form a latent image, and the developing unit 3
Develop by. The developing means 3 includes a toner reservoir 3a.
The toner inside is sent out by the toner sending member 3b, and the developing sleeve 3d having the fixed magnet 3c built therein is rotated.
A toner layer to which a triboelectric charge has been applied by the developing blade 3e is formed on the surface of the developing sleeve 3d, and the toner is transferred to the photosensitive drum 1 according to the latent image, thereby forming a toner layer and visualizing it. To do. After the toner image is transferred to the recording medium (not shown), the cleaning blade 4a scrapes off the toner remaining on the photosensitive drum 1, and the squeegee sheet 4b scoops it off and collects it in the waste toner reservoir 4c. It is configured to remove the residual toner on the drum 1. Each component such as the photosensitive drum 1 includes a toner container 5 that forms a toner reservoir 3a, a developing frame body 6a that holds a developing sleeve 3d, a cleaning frame body 6b that holds the photosensitive drum 1, the charging roller 2, and a cleaning unit 4. The cartridge 11 is housed in a housing 11 configured by being combined with each other to form a cartridge, and the cartridge is mounted to a cartridge mounting unit provided in the main body of the image forming apparatus.

Next, the structure of the electrical contact member for grounding the photosensitive drum 1 will be described.

As shown in FIG. 3, the photosensitive drum 1 has flanges 8 fitted and fixed at both ends thereof, and the flanges 8 are rotatably fitted to the drum shaft 15. The drum shaft 15 penetrating in the longitudinal direction is fixed to the cleaning frame 6b. A drum ground electrode 16 is attached to one of the flanges 8 fitted and fixed on both ends of the photosensitive drum 1 in the longitudinal direction and rotatably fitted on the drum shaft 15. Drum ground electrode 1
When the photosensitive drum 1 is rotated by the driving force of the drum gear 9 which is joined to the end surface of the flange 8 inside the photosensitive drum 1 and which is integral with one flange 8, the photosensitive drum 1 is rotated.
Along with this, the conductive resin member 20 of the drum ground electrode 16 slides on the outer peripheral surface of the drum shaft 15 to serve as a contact. When the process cartridge A is attached to the image forming apparatus main body, the base end portion of the drum shaft 15 comes into contact with a ground contact (not shown) of the image forming apparatus main body.

The drum ground electrode 16 is crimped by a heat caulking member 10 which inserts a disc 16a in contact with the end face of the flange 8 inside the photosensitive drum 1, or is fixed with a small screw, and is bent from the outer periphery of the disc 16a. An arm 16b that obliquely faces the drum shaft 15 is provided. The tip of the arm 16b is provided with a mounting portion 16c of the conductive resin member 20 that is parallel to the axial direction of the drum shaft 15 and faces the drum shaft 15. The arm 16b is provided at a position where the disc 16a is equally divided, and the conductive resin member 20 contacts the drum shaft 15 at different positions in the axial direction of the drum shaft 15.

In the above description, the drum ground electrode 16 is a conductive spring material such as spring steel or beryllium phosphor bronze.

As shown in FIGS. 2 and 4, the conductive resin member 20 is used.
Is a mounting portion 16c of the drum ground electrode 16 on the base 20a.
Has a mounting surface 20b in contact therewith, and the surface on the opposite side of the mounting surface 20b is an arc surface 20c which is substantially concentric with the drum shaft 15 and has a radius larger than that of the drum shaft 15. A cylindrical dowel 20d is erected on the mounting surface 20b, and the dowel 20d is fitted between the ends of the cantilevered cut-and-raised parts 16d provided at the center of the mounting part 16c of the drum earth electrode 16 by driving a drive fit. , Flat plate cut and raised part 16
A conductive resin member 20 is attached to the drum ground electrode 16 by bending d against elasticity.

A projection 21 is provided on the arc surface 20c of the conductive resin member 20. The protrusion 21 has a semi-cylindrical shape having a center parallel to the drum shaft 15, and the generatrix lines of the drum shaft 15 and the protrusion 21 are arranged so as to be in contact with each other. Protrusion 2
1 may be the same material as the conductive resin member 20 or may be two-color molded differently, and is integrally molded with the conductive resin member 20. The number of protrusions 21 is at least two per one side of the conductive resin member 20.

In the above, the conductive resin member 20 is brought into contact with the drum shaft 15 made of steel, for example, by the spring pressure at the tip of the drum ground electrode 16. Conductive resin member 20 by spring pressure
The load applied to the protrusion 21 is preferably about 50 to 200 g.
The conductive resin member 20 is a member in which a conductive material such as carbon fiber, potassium titanate (whisker), and stainless fiber is filled in a resin such as polyacetal (POM), polyphenylene sulfide (PPS), and polybutylene terephthalate (PBT). There are conductive resins such as CE-20 (manufacturer polyplastics), C-600SG (manufacturer Idemitsu Material), and AB362 (manufacturer Otsuka Chemical).

As the process cartridge, the charging means, the developing means or the cleaning means and the electrophotographic photosensitive member are integrally made into a cartridge, and the cartridge can be attached to and detached from the main body of the image forming apparatus.
Further, at least one of the charging means, the developing means, and the cleaning means and the electrophotographic photosensitive member are integrally made into a cartridge so that it can be attached to and detached from the main body of the image forming apparatus. Further, it means that at least the developing means and the electrophotographic photosensitive member are integrally made into a cartridge so as to be attachable to and detachable from the apparatus main body.

(Embodiment 2) In this embodiment, at least the photosensitive drum does not constitute a process cartridge with any of the process means.

In FIG. 6, the developing unit 23 on the original table 21 is scanned by the scanning optical system 22, the optical image thereof is projected on the photosensitive drum 1, and electrostatically on the photosensitive drum 1 uniformly charged by the charging roller 2. A latent image is formed, and this image on the photosensitive drum 1 is developed by the developing means 3 equipped with the developing sleeve 3d and becomes a developed image. On the other hand, the transfer material P of the recording medium is sent to the registration roller pair 25 by the paper feeding device 24 and the registration roller 25 is rotated by adjusting the timing to the developed image so that the developed image and the transfer material P coincide with each other.
To the transfer material P, and the developed image is transferred to the transfer material P.
The transfer material P is sent to the fixing device 28 by means of 7, and the fixed transfer material P is discharged from the paper discharge port 17 onto the paper discharge tray 29.

In the above, the photosensitive drum 1 in the first embodiment has the drum shaft 15 fixed to the frame of the apparatus main body at the back side of the apparatus main body, and the photosensitive drum 1 can be pulled out to the front side of the apparatus main body.

FIG. 7 shows a mounting portion of the photosensitive drum 1 of this embodiment. The drum shaft 15 is a frame 3 on the back side of the apparatus main body.
1 is press-fitted into a boss 33 that is fixed by a small screw 32 to the drum shaft 1.
4 is rotatably fitted, and the drum gear 34 meshes with a drive gear train (not shown). A dowel 35 axially protruding from the end surface of the drum gear 34 is slidably fitted in an axial hole 8a provided in the flange 8 on the back side of the photosensitive drum 1. In order to prevent the axial escape of the drum gear 34, the drum shaft 1
A shaft retaining ring 36 is fitted in the circumferential groove of the shaft 5.
The end of the drum shaft 15 on the front side of the apparatus main body is a reduced diameter portion 15a, and a male screw is provided on the outer periphery of the reduced diameter portion 15a. A collar 37 that is in contact with the end face of the front flange 8 is fitted into the reduced diameter portion 15a, and a nut 38 is screwed into it. The nut 38 is a locked type nut. A tapered portion 15b is provided adjacent to the reduced diameter portion 15a of the drum shaft 15 so that the conductive resin member 20 can easily enter the drum shaft 15.

In the above-mentioned image forming apparatus, the charging roller 2, the developing means 3 and the cleaning means 4 are each slightly equipped with the photosensitive drum 1.
It is provided so that it can be retracted away from the surface of the. The transfer roller 26 is attached to the frame of the conveying device 27, and the frame is oscillated clockwise around the roller 27 a of the conveying device 27 so as to be separated from the photosensitive drum 1.

The photosensitive drum 1 includes the charging roller 2, the developing means 3, the cleaning means 4, and the transfer roller 26 as described above.
Are separated from the surface of the photosensitive drum 1, the nut 38 is loosened, the collar 37 is removed, and the collar is pulled out to the front side of the apparatus main body.
It can be slid in the axial direction and removed to the outside of the drum shaft 15.

To mount the photosensitive drum 1, the flange 8 on the back side is inserted into the drum shaft 15, the conductive resin member 20 then comes into contact with the tapered portion 15b of the drum shaft, and subsequently the arm 16b. Against the spring force of the drum shaft 15
Enter the large diameter part of and slide to the back side. Finally, the front flange 8
Enters the drum shaft 15, and the hole 8a of the flange 8 on the back side is fitted into the dowel 35 of the drum gear 34. Then, the collar 37 is fitted to the reduced diameter portion 15a of the drum shaft, and the nut 38 is screwed in.

[0039]

According to the first aspect of the present invention, an electrophotographic photosensitive member, a process means acting on the electrophotographic photosensitive member, and the image bearing member are formed into an image in a process cartridge which can be attached to and detached from an image forming apparatus main body. It has an electric contact member for grounding to the main body of the device, and since the electric contact member is a conductive resin member, generation of abnormal noise or noise is made without applying grease such as a contact between metals. Can be prevented. Further, since the grease application is unnecessary, the workability is improved and the automation of the production line is easily supported, so that the quality is further stable and the price can be reduced.

A second invention of the present invention is the same as the first invention, wherein the electric contact member is brought into contact with an outer peripheral surface of a shaft supporting the electrophotographic photosensitive member, whereby the material of the shaft and the electric contact member is The effect of the combination is even more effective because it slides on a shaft with a low peripheral speed.

In a third aspect of the present invention, in the second aspect, the two or more electric contact members are provided so that, for example, foreign matter is attached to the outer peripheral surface of the drum shaft and the conductive resin on one side is provided. Even if a member causes a contact failure for a moment, another
The individual conductive resin members are not in contact with the drum shaft to cause a ground failure.

According to a fourth aspect of the present invention, in the third aspect, the two or more electric contact members are arranged at different positions in the longitudinal direction of the electrophotographic photosensitive member to support the image carrier. The durability of the sliding surface of the shaft is increased, and even if a part of the sliding surface deteriorates, the remaining sliding surface is in good contact with the conductive resin member, so that reliability and durability are further increased.

According to a fifth aspect of the present invention, in the fourth aspect, the electric contact member has two or more protruding portions, so that the conductive material in the resin is concentrated on the protruding portions and protrudes to the surface. By bringing this protrusion into contact with the drum shaft, good electrical conductivity is achieved. Further, if two or more protrusions are provided, even if one of the protrusions is defective in conduction, the other protrusion is conductive and no contact failure occurs.

In a sixth aspect of the present invention according to any one of the first to fifth aspects, the process cartridge includes a charging means, a developing means or a cleaning means as the process means, and an electrophotographic photoreceptor. Since the cartridge is integrated into a cartridge and the cartridge can be attached to and detached from the main body of the image forming apparatus, there is no abnormal noise or noise generated from the process cartridge and no grease is applied, so that the process cartridge can be assembled. It will be easy.

In a seventh aspect of the present invention according to any one of the first to fifth aspects, the process cartridge is at least one of a charging means, a developing means, a cleaning means as the process means, and an electrophotographic apparatus. Since the photosensitive member is integrally formed into a cartridge that can be attached to and detached from the main body of the image forming apparatus, there is no abnormal noise or noise generated from the process cartridge, and no grease is applied, so that the process cartridge can be assembled. It will be easy.

An eighth aspect of the present invention is the process cartridge according to any one of the first to fifth aspects, wherein at least the developing means as the process means and the electrophotographic photosensitive member are integrally formed. By making the process cartridge removable and attachable to the apparatus main body, there is no abnormal noise or noise generated from the process cartridge and no grease is applied, so that the process cartridge can be easily assembled.

A ninth aspect of the present invention is an electrophotographic photoreceptor,
A process cartridge acting on the electrophotographic photosensitive member and an electric contact member for grounding the electrophotographic photosensitive member to the main body of the image forming apparatus are provided. The electric contact member is a conductive resin member, and the process cartridge is removable. An image forming apparatus comprising: a mounting unit for mounting the recording medium on the recording medium; and a conveying unit that conveys the recording medium.

According to a tenth aspect of the present invention, in the ninth aspect, the electric contact member comes into contact with an outer peripheral surface of a shaft fixed to a main body of an image forming apparatus which rotatably supports the electrophotographic photosensitive member. As a result, the effect of the combination of the materials of the shaft and the electrical contact member is more effective because it slides on the shaft having a low peripheral speed.

The eleventh invention of the present invention is the tenth invention, wherein two or more electric contact members are provided, so that, for example, foreign matter is attached to the outer peripheral surface of the drum shaft and the conductive resin on one side is provided. Even if the member causes a contact failure for a moment, the other conductive resin member is in contact with the drum shaft and does not cause a ground failure.

The twelfth invention of the present invention is the electrophotographic photoreceptor according to the eleventh invention, wherein the two or more electric contact members are arranged at different positions in the longitudinal direction of the electrophotographic photoreceptor. The durability of the sliding surface of the supporting shaft is increased, and even if part of the sliding surface deteriorates, the remaining sliding surface makes good contact with the conductive resin member, further increasing reliability and durability. .

The thirteenth invention of the present invention is the twelfth invention, wherein the electric contact member has two or more protruding portions, so that the conductive material in the resin is concentrated on the protruding portions and protrudes to the surface. By bringing this protrusion into contact with the drum shaft, good electrical conductivity is achieved. Further, if two or more protrusions are provided, even if one of the protrusions is defective in conduction, the other protrusion is conductive and no contact failure occurs.

A fourteenth invention of the present invention comprises an image carrier, process means acting on the image carrier, and an electric contact member for grounding the image carrier to the main body of the image forming apparatus. Since the contact member is a conductive resin member, it is possible to prevent the generation of abnormal noise or noise without applying grease such as a contact between metals. Further, since the grease application is unnecessary, the workability is improved, the quality is more stable, and the price can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a process cartridge.

FIG. 2 is a front view of the photosensitive drum viewed from a direction perpendicular to the axis.

FIG. 3 is a vertical cross-sectional view of FIG.

FIG. 4 is a perspective view of a conductive resin member of a drum ground electrode.

FIG. 5 is a vertical sectional view of the image forming apparatus.

FIG. 6 is a vertical sectional view of the photosensitive drum in FIG.

[Explanation of symbols]

 1 Photosensitive Drum 2 Charging Roller 3 Developing Means 3a Toner Reservoir 3b Toner Feeding Member 3c Fixed Magnet 3d Developing Sleeve 3e Developing Blade 4 Cleaning Means 4a Cleaning Blade 4b Squisheet 4c Waste Toner Reservoir 5 Toner Container 6a Developing Frame 6b Cleaning Frame 15 Drum Shaft 16 Drum ground electrode 20 Conductive resin member 21 Protrusion

Claims (14)

[Claims] 1. A process cartridge attachable to and detachable from an image forming apparatus main body, comprising: an electrophotographic photosensitive member; process means acting on the electrophotographic photosensitive member; and grounding the electrophotographic photosensitive member to the image forming apparatus main body. An electric contact member, wherein the electric contact member is a conductive resin member. 2. The process cartridge according to claim 1, wherein the electric contact member is in contact with an outer peripheral surface of a shaft supporting the electrophotographic photosensitive member. 3. The process cartridge according to claim 2, wherein two or more electric contact members are provided. 4. The process cartridge according to claim 3, wherein the two or more electric contact members are arranged at different positions in the longitudinal direction of the electrophotographic photosensitive member. 5. The process cartridge according to claim 4, wherein the electric contact member has two or more protruding portions. 6. The process cartridge comprises a charging means, a developing means or a cleaning means as the process means and an electrophotographic photosensitive member which are integrally formed into a cartridge, and the cartridge can be attached to and detached from the main body of the image forming apparatus. 6. The method according to claim 1, wherein
The process cartridge according to any one of 1. 7. The process cartridge is configured such that at least one of a charging unit, a developing unit, and a cleaning unit as the process unit and an electrophotographic photosensitive member are integrally made into a cartridge and can be attached to and detached from an image forming apparatus main body. The process cartridge according to any one of claims 1 to 5, wherein the process cartridge comprises: 8. The process cartridge is a cartridge in which at least a developing device as the process device and an electrophotographic photosensitive member are integrally made into a cartridge, which is attachable to and detachable from the apparatus main body. 5. The process cartridge according to any one of 5 to 5. 9. An electric contact member, comprising: an electrophotographic photosensitive member; process means acting on the electrophotographic photosensitive member; and an electric contact member for grounding the electrophotographic photosensitive member to an image forming apparatus main body. Is an image forming apparatus comprising: mounting means for removably mounting a process cartridge, which is a conductive resin member, and transporting means for transporting the recording medium. 10. The image forming apparatus according to claim 9, wherein the electric contact member is in contact with an outer peripheral surface of a shaft fixed to an apparatus body of the image forming apparatus that rotatably supports the electrophotographic photosensitive member. . 11. The image forming apparatus according to claim 10, wherein two or more electric contact members are provided. 12. The image forming apparatus according to claim 11, wherein the two or more electric contact members are arranged at different positions in the longitudinal direction of the electrophotographic photosensitive member. 13. The image forming apparatus according to claim 12, wherein the electrical contact member has two or more protruding portions. 14. An image carrier, a process means acting on the image carrier, and an electric contact member for grounding the image carrier to the main body of the image forming apparatus, wherein the electric contact member is a conductive resin. An image forming apparatus, which is a member.