CN112764338B

CN112764338B - Drive head, photosensitive drum and processing box

Info

Publication number: CN112764338B
Application number: CN202110099873.2A
Authority: CN
Inventors: 易新华; 杨晓锋
Original assignee: Print Rite Unicorn Image Products Co Ltd
Current assignee: Print Rite Unicorn Image Products Co Ltd
Priority date: 2021-01-25
Filing date: 2021-01-25
Publication date: 2025-01-10
Anticipated expiration: 2041-01-25
Also published as: CN112764338A

Abstract

The driving head is used for receiving torque of a driving rod of a laser printer and comprises a body and a driven rod which moves back and forth in the axial direction relative to the body, the body is provided with an inner cylinder part and an outer cylinder part which are coaxially arranged, the inner cylinder part and the outer cylinder part are connected through a connecting part in the radial direction, two ends of the outer cylinder part are open, one end of the inner cylinder part is open, the other end of the inner cylinder part is a sealed bottom plate, a limiting hole is arranged in the center of the bottom plate, more than three through strip-shaped openings are formed in the center of the bottom plate, one end of each through strip-shaped opening is communicated with the limiting hole, the length direction of each through strip-shaped opening is radial, more than three through strip-shaped openings are uniformly distributed in the circumferential direction, and the driven rod is provided with a limiting disc in clearance fit with the inner cylinder part and an axial limiting head matched with the limiting hole. The drive head with the structure is arranged on the photosensitive drum and the processing box. The device has the advantages of simple structure, convenient assembly and high imaging quality.

Description

Driving head, photosensitive drum and processing box

Technical Field

The present invention relates to a drive head for transmitting rotational force, and a photosensitive drum and a process cartridge each having the drive head as a constituent member thereof.

Background

The process cartridge is an image forming process of a laser printer which basically constitutes a core, and is that the photosensitive drum surface is uniformly charged by a charging roller. The laser scanner emits a modulated laser beam containing image information toward the outer cylindrical surface of the photosensitive drum, and forms an electrostatic charge distribution pattern having a difference in distribution, that is, an electrostatic latent image corresponding to an image to be printed, on the cylindrical surface of the photosensitive drum after irradiation with the laser beam. Then, the developer such as carbon powder from the developing roller is absorbed on the surface of the photosensitive drum in a state of adjusting the layer thickness by the powder outlet knife, and the electrostatic latent image is covered and then converted into a visible image which can be observed by naked eyes. Along with the rotation of the photosensitive drum, the visible image formed on the surface of the photosensitive drum by the carbon powder is transposed to the position of the transfer roller. The toner in the form of a visible image is transferred onto the surface of a recording medium such as paper by the action of transfer voltage carried by the transfer roller, and then heated and pressurized by the heating roller and the pressurizing roller, so that the toner is infiltrated into a fiber layer of the recording medium, and the visible image formed by the toner is permanently solidified on the recording medium. After the visible image on the photosensitive drum is transferred by the transfer roller, residual carbon powder attached to the visible image is scraped into a waste powder collecting bin by a waste powder scraping blade, and the surface of the photosensitive drum is restored to a standby state without electricity and dust after static electricity is eliminated by corresponding electricity eliminating equipment. This completes a basic imaging workflow. The image required by the printer can be obtained as a result of the repeated circulation operation of the flow.

U.S. patent document US2008/0152388A1 discloses a process cartridge having a ball-and-socket type universal joint in a drive head at the end of a photosensitive drum. Such ball and socket joints are prone to undesirable separation, particularly during transportation, which is more likely to occur, resulting in loss of the ball and socket joint's transmission function or unstable operation.

As an improvement of the technical solution disclosed in US2008/0152388A1, there is a driving head as shown in fig. 10, which is formed by assembling a body 1, a driven rod 2, a spring 3, a pin 4, a limiting member 5 and a positioning member 6, and has a relatively complex structure, and is relatively troublesome to assemble, and further simplified in structure, on the other hand, after the limiting member 5 is fixed in the inner cavity of the body 1, the out-of-roundness of the gear portion on the body 1 is affected when the radial extrusion force between the two is too large, so that the problem of imaging quality occurs, and therefore, the necessity of improved design is more increased.

Disclosure of Invention

The invention mainly aims to provide a driving head which is simple in structure and convenient to assemble;

another object of the present invention is to provide a photosensitive drum constructed by the above-described drive head;

It is still another object of the present invention to provide a process cartridge constructed of the above photosensitive drum.

The driving head comprises a body and a driven rod which moves back and forth in the axial direction relative to the body, wherein the body is provided with an inner cylinder part and an outer cylinder part which are coaxially arranged, the inner cylinder part and the outer cylinder part are connected through a connecting part in the radial direction, two ends of the outer cylinder part are open, one end of the inner cylinder part is open, the other end of the inner cylinder part is a sealed bottom plate, the center of the bottom plate is provided with a limiting hole, more than three through strip-shaped openings are arranged, one end of each through strip-shaped opening is communicated with the limiting hole, the length direction of each through strip-shaped opening is along the radial direction, more than three through strip-shaped openings are uniformly distributed in the circumferential direction, and the driven rod is provided with a limiting disc which is in clearance fit with the inner cylinder part and an axial limiting head which is matched with the limiting hole.

According to the scheme, as the body is arranged into the structure form of the inner cylinder part and the outer cylinder part, namely, the inner cylinder part is arranged in the cylinder body in the prior art, the out-of-roundness influence of other parts assembled in the inner cylinder part on the outer cylinder part is relatively isolated, and the radial acting force of the limiting disc and the driven rod on the inner cylinder part is reduced by arranging the limiting disc and the driven rod into a whole, so that the out-of-roundness influence on the outer cylinder part is avoided. In addition, the locating piece in the prior art is omitted by matching the axial locating head with the locating hole, so that the assembly efficiency is improved while the parts of the driving head are reduced. The diameter of the limiting hole can be enlarged when the limiting head is subjected to axial force through more than three through strip-shaped openings, so that the limiting head can be conveniently extruded and penetrated axially during assembly.

The connecting part is a torus, and the torus is approximately positioned in the middle of the outer cylinder in the axial direction. The scheme can minimize the influence degree on the outer cylinder part when the axis of the inner cylinder part generates rotation angle change

In another further scheme, a plurality of reinforcing ribs are axially arranged between the outer cylinder part and the inner cylinder part, the reinforcing ribs extend from the connecting part to the direction of the bottom plate, the reinforcing ribs are uniformly distributed in the circumferential direction, and more than three through strip-shaped openings extend to the circumferential wall of the inner cylinder part in the radial direction and extend on the circumferential wall along the axial direction. The advantage of this scheme is can strengthen the support to the inner tube portion.

In a further scheme, the distance between the reinforcing rib and the adjacent end of the through strip-shaped opening in the axial direction is greater than or equal to zero. According to the scheme, the inner cylinder part is supported while the elasticity of the limiting hole can reach the design requirement in a selectable range.

In a further aspect, a mark is provided on a visible surface of the open end of the inner cylinder or the end of the outer cylinder in the same direction, and the mark is used for presetting torsion reference to a spring when the driven rod is assembled to the body. The advantage of this scheme is the production assembly of the drive head of being convenient for.

Still further, the marks may be symmetrically arranged protrusions or depressions. The scheme has the advantages that the mark is striking and is not easy to disappear.

To achieve another object of the present invention, there is provided a photosensitive drum having one end provided with the drive head described in any one of the above aspects.

In order to achieve the further object of the present invention, the present invention provides a process cartridge comprising a cartridge body on which the photosensitive drum according to the above-described aspect is mounted.

Drawings

FIG. 1 is an exploded view of a drive head embodiment of the present invention;

FIG. 2 is a perspective view of an embodiment of the drive head of the present invention;

FIG. 3 is a cross-sectional view of an embodiment of the drive head of the present invention;

FIG. 4 is a front view of the present body;

FIG. 5 is a top view of FIG. 4;

FIG. 6 is a bottom view of FIG. 4;

FIG. 7 is a perspective view of the body;

FIG. 8 is a perspective view of an embodiment of a photosensitive drum of the present invention;

FIG. 9 is a perspective view of an embodiment of a process cartridge of the present invention;

fig. 10 is an exploded view of a conventional drive head.

The invention is further described below with reference to various embodiments and the accompanying drawings.

Detailed Description

The drawings are merely schematic representations, wherein like numerals indicate like structures, and which are particularly described in text, except for a slight difference.

In addition, only the structure different from the prior art from the present invention will be described in detail below, but the working principle of the drive head itself and other structures related to the present invention, as well as the structures of the photosensitive drum and the process cartridge, will be understood and implemented by those skilled in the art with reference to the prior art of the present invention, disclosure of patent document CN103376696A, CN104155864a, etc.

Drive head embodiment

Referring to fig. 1 and 2, the driving head according to the present invention is used for meshing with a driving rod of a laser printer, receiving and transmitting torque, and is assembled by three parts of a body 1, a driven rod 2and a spring 3, wherein the spring 3 is installed in the body 1 in a pressed and twisted manner, a main body of the spring 3 is sleeved on a rod body of the driven rod 2, and the spring 3 is a compression spring and is also a torsion spring. The body 1 has an outer cylinder 11, an inner cylinder 12, and a connecting portion 13 disposed therebetween, the outer cylinder 11 and the inner cylinder 12 being coaxially disposed, and as can be seen in fig. 3, the connecting portion 13 of this example is a torus, an outer circle of which is connected to the outer cylinder and an inner circle of which is connected to the inner cylinder, as seen in a radial direction. Two recesses 124 as marks are symmetrically provided on the open end face of the inner cylinder 12, and a pair of force receiving portions 125 are symmetrically provided on the inner wall. The spring 3 has one end of a hook 32 which is planar in the circumferential plane and the other end of a hook 31 which is planar in the radial plane. The upper end of the driven rod 2 is provided with a pair of meshing teeth 25 meshed with the driving rod, and a limiting disc 21 in clearance fit with the inner barrel 12, a pair of force transmission parts 24 symmetrically arranged, a rod body 23 and an axial limiting head 22 are sequentially arranged from top to bottom. The spring 3 is sleeved outside the rod body 23, and the hook 32 is sleeved on one of the force transmission parts 24.

Referring to fig. 3, the outer cylinder 11 is open at both ends, the gear portion is provided at the outer periphery of the upper end, the lower end is provided for inserting the drum of the photosensitive drum and is fixed to the end of the drum, while the inner cylinder 12 is connected only by the connecting portion 13, and the connecting portion 13 is located approximately in the middle of the outer cylinder 11 in the axial direction, i.e., away from both ends, and the inner cylinder 12 is not directly affected by the out-of-roundness of the outer cylinder 11 due to the out-of-roundness change or the axis inclination occurring during the assembly or operation of the driven lever 2. The upper end of the inner cylinder 12 is open, the lower part is a sealed bottom plate 121, a limiting hole is arranged in the center of the bottom plate 121, a pair of spring seats 126 are symmetrically arranged on one side of the bottom plate 121 positioned on the inner cylinder 12, the hooks 31 at the other end of the spring 3 are hooked on the spring seats 126 in a form of generating torsion restoring force, and the diameter of the axial limiting head 22 is slightly larger than the diameter of the limiting hole in a natural state, so that the spring 3 is simultaneously arranged in the cavity of the inner cylinder 12 in a pressed mode. In the state shown in fig. 3, when one end of the engagement tooth 25 receives an axial external force from the laser printer driving rod to overcome the axial restoring force of the spring 3, the driven rod 2 moves linearly along the axis downwards relative to the body 1, and after the external force disappears, the driven rod moves upwards under the action of the axial restoring force of the spring 3 until the axial limiting head 22 is blocked by the limiting hole.

Referring to fig. 4 and 5, fig. 4 is a front view of the body 1, fig. 5 is a top view of the body 1, the force receiving portion 125 is disposed on the inner wall of the inner barrel 12, and the force receiving portion 125 is matched with the force transmitting portion 24 to transmit torque in the driving head on one hand, and is matched with the limiting disc 21 to limit the downward movement of the driven rod 2 when the driven rod 2 is downward. The bottom plate 121 is provided with a limiting hole 122 in the center and four through strip openings 123, one end of each through strip opening 123 is communicated with the limiting hole 122, the length direction of the through strip opening is along the radial direction, the four through strip openings 123 are uniformly distributed when seen from the circumferential direction, and a cross opening taking the limiting hole 122 as the center is formed on the bottom plate 121. As previously described, the bottom plate 121 is also provided with a pair of spring seats 126 on the inside thereof.

Referring to fig. 6, fig. 6 is a bottom view of the body 1, and eight reinforcing ribs 111 are provided between the outer cylindrical portion 11 and the inner cylindrical portion 12, which are uniformly distributed in the circumferential direction.

Referring back to fig. 3, the reinforcing ribs 111 are axially arranged, extend from the connecting portion 13 toward the bottom plate 121, and in this example, extend radially to the peripheral wall of the inner tube 12 and axially on the peripheral wall through the strip-like openings 123. In fig. 3, the distance between the downward extending reinforcing ribs 111 and the adjacent end of the upward extending through strip-shaped opening 123 in the axial direction is 1mm, and the distance between the two extending in the axial direction can be determined according to the hardness, elasticity, structural dimension and other factors of the body material, so as to achieve the expansion requirement required when the limiting hole 122 is assembled, the limiting function during working and the strength requirement of the inner cylinder.

Referring to fig. 7, fig. 7 is a perspective view from the open end of the inner cylindrical portion 12, more clearly showing the positional relationship among the bottom plate 121, the limiting hole 122, the through-strip-shaped opening 123, the spring seat 126, and the force receiving portion 125.

Assembly of drive head

Referring to fig. 1, during the assembly of this embodiment, the spring 3 is first sleeved on the rod body 23, the hook 32 at one end is hooked on one force transmission portion 24, then the hook 31 at the other end of the spring 3 is hooked on the spring seat 126, when the limiting disc 21 is located at the upper end of the force bearing portion 125, the driven rod 2 is rotated counterclockwise to the position shown in fig. 2 relative to the body 1, that is, when the connecting line of the pair of engaging teeth 25 is overlapped with the connecting line of the pair of concave portions 124, the driven rod 2 is pressed down in the axial direction, the axial limiting head 22 presses the limiting hole 122, and due to the existence of the through strip-shaped opening 123, the diameter of the limiting hole 122 expands, and when the axial limiting head 22 passes through the limiting hole 122, the limiting hole 122 rebounds to the diameter in a natural state, and forms a clearance fit with the rod body 23, thereby completing the assembly of the whole driving head.

Other embodiments of the drive head

Other embodiments according to the inventive concept may have the following aspects. The connection 13 may also be a discontinuous torus, even a spoke-like connection if the material strength is sufficient. The through-strip-shaped openings 123 should be provided in three at a minimum, and when the elasticity of the material from which the body 1 is made is excessively small, the number of the through-strip-shaped openings should be increased so as to facilitate assembly, and of course, if the elasticity of the material is large, the length of the through-strip-shaped openings 123 may be limited to the bottom plate 121, even without reaching the boundary of the bottom plate 121. Obviously, the recess 124 serving as the mark may be a protrusion, or may be provided on the visible surface of the outer tube 11 at the same end. The above-described variants can likewise achieve the corresponding object of the invention.

Photosensitive drum embodiment

Referring to fig. 8, since the present invention is mainly an improvement of the driving head 100, the photosensitive drum according to the present invention is provided with the driving head 100 in the above-described various embodiments at one end of the drum 200.

Process cartridge embodiment

Referring to fig. 9, also because the present invention is mainly an improvement of the drive head 100, the process cartridge according to the present invention is a photosensitive drum with the drive head 100 described above rotatably mounted between both end walls of the cartridge body 300.

Claims

1. A driving head, used to receive the torque of a driving rod of a laser printer, comprising a body and a driven rod that reciprocates axially relative to the body;

Features:

The body comprises an inner cylinder portion and an outer cylinder portion arranged coaxially, wherein the inner cylinder portion and the outer cylinder portion are connected in radial direction via a connecting portion;

The two ends of the outer cylinder are open;

The inner cylinder is open at one end and is sealed at the other end. A limit hole is provided at the center of the bottom plate, and more than three through strip openings are provided. One end of the through strip opening is connected to the limit hole and the length direction is radial. The more than three through strip openings are evenly distributed in the circumferential direction.

The driven rod has a limit plate that is clearance-matched with the inner cylinder and an axial limit head that is blocking-matched with the limit hole. The diameter of the axial limit head is slightly larger than the diameter of the limit hole in a natural state. The diameter of the limit hole expands when subjected to axial force, which facilitates axial extrusion of the axial limit head during assembly. After the axial limit head passes through the limit hole, the limit hole rebounds to the diameter in the natural state, forming a clearance fit with the rod body of the driven rod.

2. The drive head according to claim 1, characterized in that:

The connecting portion is a circular ring, and the circular ring is approximately located in the middle of the outer cylinder in the axial direction.

3. The drive head according to claim 1, characterized in that:

A plurality of axially arranged reinforcing ribs are also provided between the outer cylinder portion and the inner cylinder portion, the reinforcing ribs extending from the connecting portion toward the bottom plate, and the plurality of reinforcing ribs are evenly distributed in the circumferential direction;

The three or more through-strip openings extend radially to the peripheral wall of the inner cylinder portion and extend axially on the peripheral wall.

4. The drive head according to claim 3, characterized in that:

The axial distance between the reinforcing rib and the adjacent ends of the through strip opening is greater than or equal to zero.

5. The drive head according to any one of claims 1 to 4, characterized in that:

A mark is provided on the visible surface of the open end of the inner cylinder or the same-direction end of the outer cylinder, and the mark is used as a reference for the pre-set torque of the spring when the driven rod is assembled to the body.

6. The drive head according to claim 5, characterized in that:

The mark is a pair of symmetrically arranged protrusions or depressions.

7. A photosensitive drum, comprising a drum, characterized in that:

A drive head according to any one of claims 1 to 6 is mounted on one end of the drum.

8. A processing box, comprising a box body, characterized in that:

The box body is mounted with the photosensitive drum according to claim 7.