JPH0943939A - Electrifying device, and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent image defect from being caused by failure to electrify a photoreceptor as an electrified at a specified potential because of conduction defect by bringing part of an elastic member in contact with a circumferential surface of a rotary shaft for electrically connecting the elastic member with the rotary shaft of an electrification roller. SOLUTION: In bringing a spring and surface 36a, extended from a spring 36 for energizing an electrifying roller 30 toward a photosensitive drum, into pressure contact with a shaft circumferential surface 31b of a core metal 31 of the electrification roller 30, it is pressurized to come in contact with it through a hole 35b in a conductive shaft bearing 35. Because the shaft bearing 35 is conductive, an electrode 40 and the core metal 31 are electrically connected to each other through the spring 36 and the shaft bearing 35. In this constitution, the spring end surface 36a is position-regulated, and the shaft circumferential surface 31b of the core metal 31 of the electrification roller 30 is directly fed. Conductivity of a feed way from a power supply 38 to the electrification roller 30 is thus improved, and stabilized, thereby generation of electrification process defective in the photoreceptor by conduction defect, or image defect by this electrification process defect can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device for charging an object to be charged such as a photoconductor and a dielectric, and a process cartridge using the charging device.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus such as an electrophotographic copying machine, a corona discharger is often used as a device for charging the surface of a charged body such as a photoconductor.
This one is equipped with a wire electrode facing the photoconductor and a shield electrode surrounding the wire electrode, and charges the photoconductor by applying an appropriate voltage thereto.

However, when such a corona discharger is used, (1) the voltage applied to the wire electrode is 4 kV.
High voltage of ~ 8kV, (2) charging current is low because most of the current flows from the wire electrode to the shield electrode, and (3) ozone is generated by corona discharge.
(4) There is a problem that discharge unevenness occurs due to contamination of the discharge wire electrode.

As a charging device for solving such a problem, there is known a so-called contact charging device for charging a charging member by directly contacting a charging member with the charging member.

FIG. 6 is a schematic diagram of an electrophotographic apparatus using the contact charging device 122. The sightseeing drum 121 as the member to be charged rotates in the direction of arrow K1, and the charging roller 130 as the charging member has its core metal (axial core, rotating shaft) 13
Both end portions of the photosensitive drum 12 are supported by bearings 135, and the bearings 135 are biased by the springs 136 toward the photosensitive drum 121.
1 under pressure to form a contact portion (nip portion) n with the photosensitive drum 121. Contact 13 from power supply 138
7, a bias voltage is applied to the charging roller 130 via the spring 136, the bearing 135, and the core metal 131 to charge the periphery of the photosensitive drum 121, and an electrostatic latent image is formed by exposure L to the charged surface. It Photosensitive drum 12
The electrostatic latent image on 1 is visualized as a toner image Ta by the developing device 123, and the toner image Ta is transferred to the sheet material P as an image Tb by the transfer unit 112. The sheet material P that has received the image transfer is heated by a fixing device (not shown) to permanently fix the toner image. Photosensitive drum 1 after transfer
The toner remaining on 21 is cleaned and removed by the cleaning device 125, and the photosensitive drum 121 is repeatedly used for image formation.

Bearings 135 for bearing-supporting both ends of the core 131 of the charging roller 130 are made of a plastic material. Of the bearings 135 at both ends, the bearing 135 for supplying power to the charging roller 130 is plastic at the time of molding. The carbon fiber is dispersed in the material so as to have conductivity so that the resistance value becomes about 10 ³ to 10 ⁴ Ω · cm. Therefore, the power source 138
From the contact point 137 and the spring 13 respectively
6. A bias voltage is applied to the charging roller 130 via the bearing 135 and the core 131 described above.

[0007]

However, in the charging device as described above, the conductive bearing 135 has a dispersion of carbon fibers in the plastic material due to the molding conditions thereof, the resistance value becomes high, and the insulating state is deteriorated. I had a physical problem. Therefore, due to poor continuity, the photosensitive member as a member to be charged cannot be charged to a predetermined potential, and an image defect may occur.

[0008]

The present invention has a charging roller for charging a body to be charged, and an elastic member for pressing the charging roller against the body to be charged, and the charging is performed via the elastic member. In a charging device capable of applying a voltage to a roller, a part of the elastic member and a peripheral surface of the rotating shaft are brought into contact with each other in order to electrically connect the elastic member and the rotating shaft of the charging roller. The feature is a charging device.

The present invention also provides a process cartridge using the charging device.

[0010]

FIG. 1 is a schematic configuration diagram of an image forming apparatus using a charging device according to the present invention. The image forming apparatus of this example is a laser beam printer using a detachable electrophotographic process of a process unit (process cartridge). FIG. 2 is an enlarged cross-sectional view of the process unit.

Reference numeral 1 is a lower housing of the printer, and 2 is an upper housing of the printer. The upper housing 2 is openable and closable about the hinge support shaft 3 in a closed state with respect to the lower housing 1 as shown by a solid line and in an opened and raised state as shown by a chain double-dashed line.

Reference numeral 4 denotes a process unit. In the present embodiment, four process devices including a drum type photoconductor 5, a charging device 6, a developing device 7 and a cleaning device 8 are mounted on a frame body 9 and attached to the printer body. It is a detachable unit. The process unit 4 raises the upper housing 2 of the printer from the lower housing 1 and raises the unit housing portion 10 inside thereof.
Then, the upper casing 2 is closed and the lower casing 1 is closed, so that the printer is mounted in a predetermined manner inside the printer.

The process unit 4 may include a photoconductor 5 and at least one of a charging device 6, a developing device 7 and a cleaning device 8.

Reference numeral 11 is a laser scanner unit, 12 is a sheet cassette, 13 is a paper feed roller, 14 is a registration roller pair, 15 is a transfer guide, 16 is a transfer charger, and 17 is a transfer charger.
Is a conveying member, and 18 is a fixing device. These are devices arranged on the lower housing 1 side of the printer. Reference numeral 11a is a laser beam reflection mirror, 19 is a paper discharge roller, 20 is a paper discharge tray, and these are devices arranged on the upper housing 2 side of the printer.

In response to the print start signal, the photosensitive member 5 is rotationally driven in the clockwise direction indicated by the arrow at a predetermined peripheral speed (process speed), and the peripheral surface of the rotating photosensitive member 5 comes into contact with the photosensitive member 5. However, the charging roller (charging member) 30 of the charging device 6 to which the bias voltage in which the AC voltage and the DC voltage are superimposed is applied is uniformly and uniformly charged.

The laser scanner unit 11 outputs a laser beam L which is modulated in accordance with the time-series electric digital pixel signal of the target image information, which is reflected by the mirror 11a to expose the frame 9 of the process unit 4. Light enters the unit 4 through the window 9a, hits the charging surface of the rotating photoconductor 5, and the surface of the rotating photoconductor 5 is scanned and exposed with the laser beam L. As a result, an electrostatic latent image corresponding to the target image information is formed on the surface of the photoconductor 5. The formed latent image is developed with the toner powder applied on the developing sleeve 7a of the developing device 7 with the layer thickness regulated by the developing blade 7b.

On the other hand, one sheet of the transfer material P is delivered from the sheet cassette 12 by the paper feed roller 13, and the photoconductor 5 and the transfer charge are transferred through the transfer guide 15 at the timing when the laser is emitted by the registration roller pair 14. The sheet is time-fed to the transfer position with the container 16. As a result, the toner powder image formed on the side of the photoconductor 5 is sequentially transferred to the surface of the transfer material P.

The transfer material P having undergone the toner powder image transfer is separated from the surface of the photoconductor 5 and is conveyed to the fixing device 18 by the conveying member 17 and passes through the nip portion between the fixing roller 18a and the pressure roller 18b to form the toner powder. After the image fixing process, the paper discharge roller 1
The sheet 9 is discharged to the sheet discharge tray 20. After transfer, the photoconductor 5 is subjected to residual toner removal by the blade 8a of the cleaning device 8 and is repeatedly subjected to image formation starting from charging.

In FIG. 2, 9c is a process unit 4
Is an opening / closing cover for the photoconductor surface exposure opening 9b of
When the process unit 4 is taken out of the printer or when the upper housing 2 is opened, it moves to the closed position to conceal and protect the exposed surface of the photoconductor.

A preferred example of the structure of the charging roller 30 as a charging member is shown in FIG. FIG. 3 is a schematic diagram of the layer structure of the charging roller 30. A conductive elastic layer 32 is provided on a conductive core metal 31 such as SUS, a high resistance elastic layer 33 is provided thereon, and a protective film 34 is provided on the surface. Conductive elastic layer 3
2 is composed of EPDM in which carbon is dispersed,
It serves to guide the bias voltage supplied to the core metal 31.
The high resistance elastic layer 33 is made of, for example, urethane rubber and contains a minute amount of conductive fine powder (for example, carbon). As an example, the charging roller 30 having high conductivity such as a pinhole of the photoconductor 5 is used. Even if you do,
The leak current is limited to prevent the bias voltage from dropping sharply. The surface protective film 34 is made of N-methylmethoxylated nylon, and the composition material of the conductive elastic layer 32 and the high resistance elastic layer 33 does not touch the photoconductor 5 to alter the surface of the photoconductor 1. As such, it acts as a protection.

FIG. 4 shows the structure of the power feeding portion for the charging roller 30. Although not shown in the drawing, the photoconductor 5 is rotatably supported by bearings on both end sides between the side plates of the process unit frame (9). G is a drum gear that is provided concentrically and integrally on one end side of the photoconductor 5. When the process unit 4 is attached to the printer main body in a predetermined manner, the gear G comes into a state of meshing with a drive gear (not shown) on the printer main body side, and the rotational force of the drive gear is applied to the photoconductor 5 via the gear G. The photoconductor 5 is transmitted and rotationally driven.

In the charging roller 30 as a charging member, both ends of a cored bar 31 which is a rotating shaft are supported by insulating bearings 35, and both bearings 35 and the process unit frame (not shown) (9). By biasing the charging roller 30 toward the photoconductor 5 by a coil-shaped spring 36 as a conductive elastic member such as SUS, which is contracted between the charging roller 30 and the photoconductor 5.
Is contacted with a predetermined pressure. The charging roller 30 rotates following the rotation of the photoconductor 5.

A core metal 30 in the axial direction of the charging roller 30.
Both end faces of the contact with the thrust stopper 42 (only one side is shown) integrally formed with the frame of the process unit 4,
The movement of the charging roller 30 in the axial direction is restricted. The thrust stopper 42 is formed of an insulating resin together with the frame of the process unit 4.

A spring end surface 36a extending from the spring 36 is in pressure contact with the shaft peripheral surface 31b of the cored bar 31. The base end portion of the electrode 40 is fixedly supported on the cartridge body 20 by thermal caulking or the like. When the process cartridge 4 is mounted at a predetermined position on the printer body, the power receiving terminal 41a on the process cartridge 4 side and the power feeding terminal 41b on the printer body side come into contact with each other and the power source 38 on the printer body side
And the electrode 40 on the process cartridge 4 side are electrically connected.

Further, in the structure of the power feeding portion of FIG. 4, the base end portion of the electrode 40 is bent and extended to the upper end side of the spring 36 and fixed under pressure to the cartridge main body 20, and the spring 36 is attached to the bent extension portion of the electrode 40. Make contact with the upper end of and receive. The spring 36 is electrically conductive, and the bearing 35 is electrically insulative, so that the electrode 40 and the cored bar 31 are electrically connected via the spring 36.

As described above, the bias voltage of the power source 38 is directly supplied from the shaft peripheral surface 31b of the conductive cored bar 31 of the charging roller 30 via the electrode 40 and a part of the conductive spring 36, so that the power source 38 is supplied. The conductivity of the power supply path to the charging roller 30 is improved, the charging process failure of the photoconductor 5 due to the failure of the conduction and the image failure due to the failure of the charging process are prevented, and the cost can be reduced. The bearing 35 does not need to be electrically conductive because the core roller 31 supplies power to the charging roller 30 directly. Therefore, since it is not necessary to include carbon in the plastic material of the bearing 35, there is also an advantage that the cost of the bearing can be reduced.

FIG. 5 is a perspective view of the main part near the end of the charging device of the present invention. That is, the charging roller 30
A spring end surface 36a extending from a spring 36 for urging the roller toward the photosensitive drum 5 is brought into pressure contact with the shaft peripheral surface 31b of the core metal 31 of the charging roller 30. Further, in this example, SUS is used as a common material for the core metal 31 and the spring 36. When the same materials are brought into contact with each other in this way, no oxide film is formed at the contact portion.

On the other hand, FIG. 10 shows a method of applying a bias voltage different from the above method. That is, the bias voltage of the power source 138 is applied to the electrode 140 of the phosphor bronze plate, and the tip portion 140a of the electrode 140 is
End surface 1 of core metal 131 made of SUS of charging roller 130
Since it is in contact with 31a, power supply to the charging roller 130 can be directly performed. The charging roller 130 is pressed against the photoconductor 121 by the spring 136 pressing the bearing 135.

In the case of FIG. 10, when the charging roller 130 moves in the axial direction, the core bar 131 may cause a contact failure with the tip end part 140a, or the core bar 131 may deform the tip end part 140a. . In addition, the phosphor bronze plate electrode 14
0 and an SUS core metal 131 generate an insulating oxide film,
Poor conduction may occur.

However, if the part 36a of the spring 36 is electrically connected to the peripheral surface 31b of the cored bar 31 as in the present embodiment, even if the cored bar 31 is moved in the axial direction, a conduction failure is less likely to occur. Further, since the electrode 40 and the core metal 31 are made of the same material, an insulating oxide film is unlikely to be formed between them.

Next, a second embodiment of the power feeding method for the charging device will be described with reference to FIGS.

FIG. 7 shows the structure of the power feeding portion for the charging roller 30. Although not shown in the drawing, the photoconductor 5 is rotatably supported by bearings on both end sides between the side plates of the process unit frame (9). G is a drum gear that is provided concentrically and integrally on one end side of the photoconductor 5. When the process unit 4 is attached to the printer main body in a predetermined manner, the gear G comes into a state of meshing with a drive gear (not shown) on the printer main body side, and the rotational force of the drive gear is applied to the photoconductor 5 via the gear G. The photoconductor 5 is transmitted and rotationally driven.

The charging roller 30 serving as a charging member has a core metal 3
Both end portions of 1 are supported by insulating bearings 35, and both bearings 35 are biased toward the photoconductor 5 by a conductive spring 36 provided between the bearings and a process unit frame (9) (not shown). Then, the charging roller 30 is brought into pressure contact with the photoconductor 5 in a predetermined manner. The charging roller 30 rotates following the rotation of the photoconductor 5. The end faces of both ends of the cored bar 30 in the axial direction of the roller 30 come into contact with an insulating resin stopper 42 (only one side is shown) integrally formed with the frame of the process unit 4 to restrict the axial movement of the roller 30a. To be done.

As shown in FIG. 7, the shaft peripheral surface 31b of the cored bar 31 is shown.
The spring end surface 36a extending from the spring 36 is in pressure contact with the. The base end portion of the electrode 40 is fixedly supported on the cartridge body 20 by thermal caulking or the like. When the process cartridge 4 is mounted at a predetermined position on the printer body, the power receiving terminal 41a on the process cartridge 4 side and the power feeding terminal 41b on the printer body side contact each other, and the power source 38 on the printer body side and the electrode 40 on the process cartridge 4 side.
And are electrically connected. The core metal and the electrode 40 are connected to the spring 36.
It is electrically connected via the (spring end portion 36a).

As described above, the bias voltage of the power source 38 is directly supplied from the shaft peripheral surface 31b of the core metal 31 of the charging roller 30 via the electrode 40 and a part of the conductive spring 36. The conductivity of the power supply path to 30 is improved, and the defective charging process of the photoconductor 5 due to the defective conductivity and the image defect due to the defective charging process are prevented.

FIG. 8 is a perspective view of the vicinity of the end of the charging device of FIG. 7, and FIG. 9 is a detailed view of an example in which the insulating bearing 35 also serves as the position restriction of the conductive spring 36. That is, when the spring end surface 36a extending from the spring 36 that biases the charging roller 30 toward the photosensitive drum 21 is brought into pressure contact with the shaft peripheral surface 31b of the core metal 31 of the charging roller, the hole 3 in the conductive bearing 35 is formed.
It can be seen that pressure contact is made through 5b. With such a configuration, the position of the spring end surface 36a is regulated, and the shaft peripheral surface 31b of the cored bar 31 of the charging roller 30 is directly fed with power, so that the power supply path from the power source 38 to the charging roller is electrically connected. It is improved and stable, and it is possible to prevent defective charging processing of the photoconductor 5 due to defective conduction and occurrence of image failure due to the defective charging processing.

Further, the power is supplied to the charging roller 30 by the spring 3.
The bearing 35 does not need to be electrically conductive because it is directly carried out from the cored bar 31 via 6. Therefore, since it is not necessary to include carbon in the plastic material of the bearing 35, there is also an advantage that the cost of the bearing can be reduced.

Next, a third embodiment of the charging device will be shown. In this embodiment, the bearing 35 shown in FIGS. 4 and 5 is made conductive. Since the configuration other than the bearing is the same as that of the embodiment shown in FIGS. 4 and 5, the description thereof will be omitted.

Since the bearing 35 is electrically conductive, the electrode 40 and the cored bar 31 are electrically connected via the spring 36 and the bearing 35.

With this configuration, the power supply 38 is connected to the charging roller 3
The power feeding path to 0 sequentially extends from the base end of the electrode 40, the conductive spring 36, the first power feeding path via the conductive bearing 35, and the base end of the electrode 40 and the conductive spring 36. There are two types of second power feeding paths for directly feeding power from the spring end surface 36a to the shaft peripheral surface 31b of the core metal 31 of the charging roller 30.

Therefore, even if the resistance value becomes high due to the molding conditions of the conductive bearing 35 and it becomes difficult to supply power to the charging roller 30, the latter second power supply path described above does not hinder the photosensitive drum 21. Can be charged, charging performance
Reliability is further improved and stabilized.

Further, since the spring end surface 36a obtained by extending the conductive spring 36 is directly fed to the shaft peripheral surface 31b of the core metal 31 of the charging roller 30, the tip of the electrode 140 such as the conventional phosphor bronze plate is provided. The portion 140a is the charging roller 1
With respect to the structure in which the end surface 131a of the SUS core bar 131 of 30 is contacted, it is possible to prevent the occurrence of conduction failure due to the generation of an insulating oxide film due to long-term storage or the like, and the electrode deformation during the assembly of parts.

Further, according to this embodiment, the cost can be reduced as compared with the above-mentioned conventional structure, and the movement of the charging roller in the axial direction can be eliminated.

Next, a fourth embodiment of the charging device will be shown. In this embodiment, the bearing 35 shown in FIGS. 7 to 9 is made conductive. Since the configuration other than the bearing is the same as that of the embodiment shown in FIGS. 7 to 9, description thereof will be omitted.

Since the bearing 35 is conductive, the electrode 40 and the cored bar 31 are electrically connected via the spring 36 and the bearing 35.

Therefore, with this configuration, the power supply path from the power source 38 to the charging roller 30 is, in order, the first power supply path via the base end portion of the electrode 40, the conductive spring 36, and the conductive bearing 35, and the electrode 40. There are two types of second power feeding paths in which power is directly fed from the base end portion, the spring end surface 36a extending from the conductive spring 36, to the shaft peripheral surface 31b of the core metal 31 of the charging roller 30.

Therefore, even if the resistance value becomes high due to the molding conditions of the conductive bearing 35 and it is difficult to supply power to the charging roller 30, the latter second power supply path described above does not hinder the photosensitive drum 21. Can be charged, charging performance
Reliability is further improved and stabilized.

Further, the spring end surface 36a obtained by extending the conductive spring 36 is directly fed to the shaft peripheral surface 31b of the core metal 31 of the charging roller 30, so that the tip portion 140a of the electrode 140 is charged as in the conventional case. The core metal 13 of the roller 130
With respect to the structure in which the first end surface 131a is contacted, it is possible to prevent the occurrence of conduction failure due to the generation of an insulating oxide film due to long-term storage or the like, and the electrode deformation at the time of assembling components.

Further, according to this embodiment, the cost is lower than that of the above-mentioned conventional structure, and the movement of the charging roller in the axial direction can be eliminated.

As shown in FIGS. 9 and 10, the charging roller 30
A spring end surface 36a extending from a spring 36 for urging the charging roller toward the photosensitive drum 21 and a shaft peripheral surface 31b of the core metal 31 of the charging roller.
When making pressure contact with, the pressure contact is made through the hole 35b in the conductive bearing 35. By adopting such a configuration and restricting the position of the spring end surface 36a, not only the charging performance, the reliability and the stability can be improved by having the above-described multiple power feeding paths, but also other components can be incorporated. It has become possible to prevent electrode deformation at the time, prevent axial movement of the charging roller, and achieve cost reduction.

Further, according to the third and fourth embodiments, since the two power supply paths are provided, even when the power supply from one power supply path is not normally performed, the other power supply path is surely provided. Power is supplied, and as a whole, the charging member is preferably supplied with power and a predetermined charge amount can be secured.

[0052]

As described above, according to the present invention, it is possible to prevent the occurrence of the defective charging process of the member to be charged due to the defective conduction of the power feeding path from the power source to the charging roller. Therefore, in the image forming apparatus using the charging device, it is possible to prevent the occurrence of the image defect due to the above-mentioned defective charging process of the photoconductor as the member to be charged.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an outline of a laser beam printer as an image forming apparatus.

FIG. 2 is an enlarged vertical sectional view of a process cartridge.

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

FIG. 4 is a front view showing a configuration of a power feeding unit according to the first and third embodiments.

5 is a perspective view of the power feeding unit of FIG.

FIG. 6 is a vertical sectional view showing a conventional image forming apparatus.

FIG. 7 is a front view showing a power feeding unit according to the second and fourth embodiments.

FIG. 8 is a perspective view of the power feeding unit of FIG.

9 is a detailed view showing the configuration of the power supply unit of FIG.

FIG. 10 is a front view of a conventional power feeding unit.

[Explanation of symbols]

 4 process cartridge 5 charged body (photosensitive drum) 6 charging device 7 developing means (developing device) 8 cleaning means (cleaning device) 30 charging member (charging roller) 31 core metal 35 bearing 36 spring (elastic member) 38 power supply 40 electrode

(72) Inventor Isao Ikemoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Shinichi Sasaki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. Within

Claims (12)

[Claims] 1. A charging roller for charging a body to be charged, and an elastic member for pressing the charging roller against the body to be charged, and a voltage can be applied to the charging roller via the elastic member. In the charging device, a part of the elastic member and a peripheral surface of the rotating shaft are brought into contact with each other in order to electrically connect the elastic member and the rotating shaft of the charging roller. 2. The charging device according to claim 1, wherein the device includes an insulating bearing member that receives the rotating shaft and is pressed by the elastic member. 3. The device includes a conductive bearing member that receives the rotating shaft and is pressed by the elastic member, and the rotating shaft and the elastic member are electrically connected via the bearing member. The charging device according to claim 1, wherein: 4. The charging device according to claim 3, wherein the bearing member regulates a position of a part of the elastic member that is in contact with the peripheral surface of the rotating shaft. 5. The charging device according to claim 1, wherein the device includes an electrode member that electrically connects the elastic member and a power supply that supplies the voltage. 6. The charging device according to claim 1, wherein the elastic member has a coil spring shape. 7. An image carrier, a charging roller that charges the image carrier, and an elastic member that presses the charging roller against the image carrier, and the charging roller is connected to the charging roller via the elastic member. In a process cartridge capable of applying a voltage, a part of the elastic member and a peripheral surface of the rotating shaft are brought into contact with each other in order to electrically connect the elastic member and the rotating shaft of the charging roller. Process cartridge. 8. The process cartridge according to claim 7, wherein the process cartridge includes an insulating bearing member that receives the rotating shaft and is pressed by the elastic member. 9. The process cartridge includes a conductive bearing member that receives the rotating shaft and is pressed by the elastic member, and the rotating shaft and the elastic member are electrically connected via the bearing member. The process cartridge according to claim 7, wherein 10. The process cartridge according to claim 9, wherein the bearing member regulates a position of a part of the elastic member that is in contact with the peripheral surface of the rotating shaft. 11. The process cartridge according to claim 7, wherein the process cartridge includes an electrode member that electrically connects the elastic member and a power supply that supplies the voltage. 12. The process cartridge according to claim 7, wherein the elastic member has a coil spring shape.