CN219179783U

CN219179783U - Process cartridge and roller acting on photosensitive drum

Info

Publication number: CN219179783U
Application number: CN202223475869.0U
Authority: CN
Inventors: 刘占伟
Original assignee: Zhuhai Dinglong New Material Co ltd
Current assignee: Zhuhai Dinglong New Material Co ltd
Priority date: 2022-12-26
Filing date: 2022-12-26
Publication date: 2023-06-13
Anticipated expiration: 2032-12-26

Abstract

The utility model discloses a process cartridge and a roller acting on a photosensitive drum. The process cartridge of the embodiment includes a photosensitive unit having a photosensitive frame on which a photosensitive drum and a charging roller for charging the photosensitive drum are provided, and a developing unit having a developing frame on which a developing roller for supplying a developer to the photosensitive drum is provided; the developing roller comprises a first elastic roller body and a first conductive plastic roller shaft penetrating through and extending out of the first elastic roller body, and the charging roller comprises a second elastic roller body and a second conductive plastic roller shaft penetrating through and extending out of the second elastic roller body. In the utility model, the developing roller and the charging roller which act on the photosensitive drum are both made of plastic roller shafts, so that the problem of imaging quality caused by deformation of an elastic roller body due to rust of the roller shafts can be avoided.

Description

Process cartridge and roller acting on photosensitive drum

Technical Field

The present utility model relates to a process cartridge of an electrophotographic image forming apparatus and a roller acting on a photosensitive drum in the process cartridge.

Background

Electrophotographic image forming apparatuses such as laser printers, copiers are generally provided with a process cartridge detachable therefrom, which includes a photosensitive drum and rollers acting on the photosensitive drum, such as a developing roller and a charging roller. In an image forming operation, the photosensitive drum is charged by a charging roller, the charged photosensitive drum is exposed to light to form an electrostatic latent image, and a developing roller supplies a developer to the photosensitive drum to develop the electrostatic latent image.

The developing roller and the charging roller generally include an elastic roller body and a roller shaft penetrating the elastic roller body, the roller shaft extending from an end of the elastic roller body so as to be mounted in position on the process cartridge. In the prior art, an iron shaft is commonly adopted as a roller shaft of a developing roller and a charging roller, a rubber roller is commonly adopted as an elastic roller body, and after a processing box is used for a long time, the elastic roller body can have local deformation (such as bulge) defects, so that even charging of a photosensitive drum and/or reliable adsorption of a developer are influenced, and imaging defects are easily caused.

Disclosure of Invention

The applicant has found that when the elastic roller body is locally deformed, the surface of the iron roller shaft corresponding to the locally deformed area is mostly corroded, i.e. the corrosion of the iron roller shaft causes the local deformation of the elastic roller body.

The main object of the present utility model is to provide a process cartridge and a roller acting on a photosensitive drum in the process cartridge, which can prevent local deformation of an elastic roller body due to rust of a roller shaft, improving image quality.

In order to achieve the above-mentioned main object, a first aspect of the present utility model discloses a process cartridge comprising:

the photosensitive unit comprises a photosensitive frame, wherein the photosensitive frame is provided with a photosensitive drum and a charging roller for charging the photosensitive drum;

a developing unit including a developing frame on which a developing roller for supplying a developer to the photosensitive drum is provided;

the developing roller comprises a first elastic roller body and a first conductive plastic roller shaft penetrating through and extending out of the first elastic roller body, and the charging roller comprises a second elastic roller body and a second conductive plastic roller shaft penetrating through and extending out of the second elastic roller body.

Further, shaft sleeves are arranged on the first conductive plastic roll shafts and are arranged at two opposite ends of the first elastic roll body; the outer diameter of the shaft sleeve is smaller than or equal to the outer diameter of the first elastic roller body.

Further, the shaft sleeve and the first conductive plastic roller shaft are of an integrated structure, and the shaft sleeve is in contact with the axial end face of the first elastic roller body.

In the utility model, the first conductive plastic roll shaft and the second conductive plastic roll shaft can be made of conductive POM, ABS, PC or PMMA materials.

According to one embodiment of the utility model, the opposite ends of the photosensitive frame are provided with supporting side plates; the developing frame is rotatably connected with the supporting side plate so that the developing unit can rotate relative to the photosensitive unit.

A second aspect of the present utility model discloses a roller acting on a photosensitive drum, which includes a roller shaft and an elastic roller body provided on the roller shaft, the roller shaft penetrating the elastic roller body and extending from an end of the elastic roller body; wherein, the roller is conductive plastic roller.

Further, the roller shaft can be made of conductive POM, ABS, PC or PMMA materials.

In a specific embodiment of the second aspect of the present utility model, the roller is a developing roller for supplying developer to the photosensitive drum, and the roller shaft is provided with sleeves at opposite ends of the elastic roller body, and the outer diameter of the sleeves is smaller than or equal to the outer diameter of the elastic roller body.

Preferably, the shaft sleeve and the roller shaft of the developing roller have an integrated structure, so that the shaft sleeve has higher size and circle runout precision, the compression amount/contact force when the elastic roller body contacts the photosensitive drum is further accurately controlled, and the imaging quality is further improved.

In another embodiment of the second aspect of the present utility model, the roller is a charging roller for charging the photosensitive drum.

The technical scheme of the utility model has the following beneficial effects:

in the utility model, the rollers (such as the developing roller and the charging roller) acting on the photosensitive drum are all made of plastic roller shafts, so that the roller shafts have no rust problem, the defect that the photosensitive drum cannot realize uniform charging and/or reliably adsorb developer due to deformation of an elastic roller body caused by rust of the roller shafts can be avoided, and the imaging quality of the processing box in long-term use can be improved.

The objects, technical solutions and advantages of the present utility model will be more clearly described below, and the present utility model will be further described in detail with reference to the accompanying drawings and the detailed description.

Drawings

FIG. 1 is a block diagram of an embodiment of a process cartridge of the present utility model;

FIG. 2 is a block diagram of a photosensitive unit in an embodiment of the present utility model;

fig. 3 is a structural view of a developing roller in an embodiment of the present utility model;

fig. 4 is a structural view of a charging roller in an embodiment of the present utility model.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present utility model, it should be understood that the following detailed description and specific examples are presented for purposes of illustration only and are not intended to limit the scope of the utility model.

As shown in fig. 1-2, the process cartridge of the embodiment includes a photosensitive unit 10 and a developing unit 20. The photosensitive unit 10 includes a photosensitive frame 11, a photosensitive drum 12, and a charging roller 13 for charging the photosensitive drum 12, the photosensitive drum 12 and the charging roller 13 being rotatably supported on the photosensitive frame 11. One end of the photosensitive frame 11 is provided with a first driving force receiving member 14 connected to the photosensitive drum 12, the first driving force receiving member 14 for receiving a rotational driving force from the electrophotographic image forming apparatus to drive the photosensitive drum 12 to rotate. The charging roller 13 is in elastic contact with the photosensitive drum 12 with a frictional force therebetween so that the charging roller 13 can rotate together with the photosensitive drum 12.

The developing unit 20 includes a developing frame 21 having a developer accommodating chamber, and a developing roller 22 for supplying developer to the photosensitive drum 12, the developing roller 22 being rotatably supported on the developing frame 21. One end of the developing frame 21 is provided with a second driving force receiving member 23, and a gear transmission mechanism is arranged between the second driving force receiving member 23 and the developing roller 22; wherein the second driving force receiving member 23 is configured to receive a rotational driving force from the electrophotographic image forming apparatus and drive the developing roller 22 to rotate through a gear transmission mechanism.

In the embodiment, the developing unit 20 is rotatably provided with respect to the photosensitive unit 10. Specifically, the photosensitive frame 11 is provided at opposite ends thereof with support side plates 111, and the developing frame 21 is rotatably connected to the support side plates 111 so that the developing unit 20 can rotate relative to the photosensitive unit 10. Wherein by changing the relative position between the developing unit 20 and the photosensitive unit 10, the developing roller 22 can be switched between an image forming state of contacting the photosensitive drum 12 and a non-image forming state of being separated from the photosensitive drum 12.

As shown in fig. 3, in the embodiment, the developing roller 22 includes a first conductive plastic roller shaft 221 and a first elastic roller body 222 provided on the first conductive plastic roller shaft 221, and the first conductive plastic roller shaft 221 penetrates the first elastic roller body 222 and protrudes from an end of the first elastic roller body 222. The first elastic roller 222 is used to load a developer, and during an image forming operation, the first elastic roller 222 contacts the photosensitive drum 12, and supplies the developer to the photosensitive drum 12 to develop the electrostatic latent image on the photosensitive drum 12.

Further, in order to precisely control the compression/contact force of the first elastic roller body 222 with respect to the photosensitive drum 12 at the time of image forming operation, a sleeve 223 may be provided on the first conductive plastic roller shaft 221, and the sleeves 223 may be provided at opposite ends of the first elastic roller body 222. Wherein, the outer diameter of the shaft sleeve 223 is smaller than or equal to the outer diameter of the first elastic roller body 222; specifically, the difference in the outer diameter of the sleeve 223 and the first elastic roller body 222 may be-0.1 mm to 0mm, for example, -0.05mm.

Preferably, the shaft sleeve 223 has an integrally formed structure with the first conductive plastic roller shaft 221. Compared with the structure of assembling the shaft sleeve 223 on the first conductive plastic roller shaft 221, the shaft sleeve 223 and the first conductive plastic roller shaft 221 adopt an integrated structure, so that the assembly gap and error between the shaft sleeve 223 and the first conductive plastic roller shaft 221 can be eliminated, the shaft sleeve 223 can be ensured to have higher size and circle run-out precision, and the compression amount/contact force when the first elastic roller body 222 contacts the photosensitive drum 12 can be controlled more accurately, thereby being beneficial to improving the imaging quality.

Further, the shaft sleeve 223 may contact with an axial end surface of the first elastic roller body 222, so that when the developing roller 22 is manufactured, the shaft sleeve 223 may be used as an axial dimension positioning reference of the first elastic roller body 222, so as to facilitate processing of the first elastic roller body 222.

As shown in fig. 4, the charging roller 13 includes a second conductive plastic roller shaft 131 and a second elastic roller body 132 provided on the second conductive plastic roller shaft 131, and the second conductive plastic roller shaft 131 penetrates the second elastic roller body 132 and protrudes from an end of the second elastic roller body 132. The second elastic roller 132 contacts the photosensitive drum 12, and charges the photosensitive drum 12 at the time of image forming operation.

In an embodiment, each of the first conductive plastic roller 221 and the second conductive plastic roller 131 may be made of POM (polyoxymethylene), ABS (acrylonitrile butadiene styrene), PC (polycarbonate) or PMMA (polymethyl methacrylate) material having conductivity. Preferably, the resistivity of the conductive PMMA, ABS, PC or POM material used is less than 10 ³ Ω.cm。

In the utility model, the developing roller 22 and the charging roller 13 which act on the photosensitive drum 12 are both made of plastic roller shafts, so that the problem that the photosensitive drum 12 cannot uniformly charge and/or reliably adsorb developer due to deformation of an elastic rubber roller body caused by rust of the roller shafts can be avoided, the imaging quality of the processing box in long-term use is improved, and the manufacturing cost of the developing roller 22 and the charging roller 13 can be reduced.

While the utility model has been described above by way of examples, it should be appreciated that the above examples are illustrative only of the possible embodiments of the utility model and should not be construed as limiting the scope of the utility model, and that equivalent substitutions or variations according to the utility model will be covered by the scope of the claims of the utility model.

Claims

1. A process cartridge, comprising:

a developing unit including a developing frame provided with a developing roller for supplying a developer to the photosensitive drum;

the method is characterized in that: the developing roller comprises a first elastic roller body and a first conductive plastic roller shaft penetrating through and extending out of the first elastic roller body, and the charging roller comprises a second elastic roller body and a second conductive plastic roller shaft penetrating through and extending out of the second elastic roller body.

2. A process cartridge according to claim 1, wherein: the first conductive plastic roll shaft is provided with a shaft sleeve, and the shaft sleeve is arranged at two opposite ends of the first elastic roll body; the outer diameter of the shaft sleeve is smaller than or equal to the outer diameter of the first elastic roller body.

3. A process cartridge according to claim 2, wherein: the shaft sleeve and the first conductive plastic roller shaft are of an integrated structure, and the shaft sleeve is in contact with the axial end face of the first elastic roller body.

4. A process cartridge according to claim 1, wherein: the first conductive plastic roll shaft and the second conductive plastic roll shaft are made of conductive POM, ABS, PC or PMMA materials.

5. A process cartridge according to claim 1, wherein: the opposite ends of the photosensitive frame are provided with supporting side plates; the developing frame is rotatably connected with the supporting side plate so that the developing unit can rotate relative to the photosensitive unit.

6. A roller acting on a photosensitive drum comprises a roller shaft and an elastic roller body arranged on the roller shaft, wherein the roller shaft penetrates through the elastic roller body and extends out of the end part of the elastic roller body; the method is characterized in that: the roll shaft is a conductive plastic roll shaft.

7. The roller for a photosensitive drum according to claim 6, wherein: the roller shaft is made of conductive POM, ABS, PC or PMMA materials.

8. The roller for a photosensitive drum according to claim 6, wherein: the roller is a developing roller for supplying developer to the photosensitive drum, shaft sleeves positioned at two opposite ends of the elastic roller body are arranged on the roller shaft, and the outer diameter of each shaft sleeve is smaller than or equal to the outer diameter of the elastic roller body.

9. The roller for a photosensitive drum according to claim 8, wherein: the shaft sleeve and the roll shaft are of an integrated structure.

10. The roller for a photosensitive drum according to claim 6, wherein: the roller is a charging roller for charging the photosensitive drum.