JPH10187009A - Cylindrical member, electrophotographic photoreceptor drum, and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cylindrical member in which a cylinder and an end engaging member are coupled with high accuracy and high strength, and trouble such as the irregularity of pitch or the disengagement of a gear is not caused, in a cylindrical member for electrophotographic (a photoreceptor drum or a developing sleeve). SOLUTION: This cylindrical member has the end engaging member 16 at least at one end of the cylinder 7d, and is constituted by bending and cutting and coupling the cylinder end with the recessed part 16g of the insertion part of the member 16 inserted into the cylinder end. In the case of bending and cutting the cylinder end by a butting tool 23, the cylinder end is bent and cut while the periphery of the cylinder end is pressurized and held by a pressurizing member 30. The accurate cylindrical member is provided by restraining a deforming force that expands the cylinder end to the outside in the case it is bent and cut.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical member, an electrophotographic photosensitive drum, and a process cartridge. Here, the electrophotographic photosensitive drum is mounted on a process cartridge and used in an electrophotographic image forming apparatus. An electrophotographic image forming apparatus forms an image on a recording medium using an electrophotographic image forming method. Examples of the electrophotographic image forming apparatus include, for example, an electrophotographic copying machine, an electrophotographic printer (for example, a laser beam printer, an LED printer, and the like), a facsimile machine, a word processor, and the like.

A process cartridge is a cartridge in which a charging unit, a developing unit or a cleaning unit and an electrophotographic photosensitive drum are integrally formed as a cartridge, and this cartridge is made detachable from an image forming apparatus main body. In addition, at least one of the charging unit, the developing unit, and the cleaning unit and the electrophotographic photosensitive drum are integrally formed as a cartridge so that the cartridge can be detachably attached to the image forming apparatus main body. Further, it means that at least the developing means and the electrophotographic photosensitive drum are integrally formed into a cartridge so as to be detachable from the apparatus main body.

[0003]

The techniques described in the gazettes described in the description of the prior art below are all very effective as a configuration of the photosensitive drum. The present invention is a further development of the prior art described above.

An object of the present invention is to provide a cylindrical member, an electrophotographic photosensitive drum, and a process cartridge having improved cylindricity.

[0005]

SUMMARY OF THE INVENTION A cylindrical member having an end engaging member at at least one end of a cylinder, wherein the cylindrical end is bent into a recess of a portion inserted into the cylindrical end of the end engaging member. A cylindrical member, wherein when bending the end of the cylinder, the end of the cylinder is bent while the periphery of the bent end of the cylinder is pressed from the outer periphery of the cylinder. It is a member.

The cylindrical member according to the present invention can minimize the minute deformation of the cylindrical end caused when the cylindrical end is bent. This is due to bending off while holding the vicinity of the cylindrical end under pressure. In other words, by holding under pressure, the deformation that expands outside the cylindrical end that occurs at the time of bending and cutting is suppressed, so that even after being bent, there is no slight deformation around the cylindrical end.

[0007] The cylindrical member according to the present invention has a strong coupling force between the cylinder and the end engaging member. This strong coupling force results from bending the cylindrical end into the recess of the end engaging member inserted into the cylindrical end. That is,
In addition to bending the cylindrical end into the recess of the end engaging member,
This is because, by bending, the bent cylindrical end can closely enter the concave portion of the end engaging member. The bending of the cylindrical end can be easily performed by the abutting member.

In the cylindrical member according to the present invention, a strong connection between each image holding member cylinder including the photosensitive drum and the end engaging member is required. It is also effective as various roller members that transmit driving force, such as a platen roller, a transport roller, a fixing roller, and a printing plate roll.

The photosensitive drum has various structures in order to obtain predetermined characteristics or according to the type of an electrophotographic process to be applied. As representative electrophotographic photoconductors, there are a photoconductor drum on which a cylindrical photoconductive layer is formed and a photoconductor drum having a protective layer on the surface, and are widely used. A photoreceptor drum composed of a cylinder and a photoconductive layer is used for image formation by the most general electrophotographic process, that is, charging, image exposure and development, and, if necessary, transfer. In addition, for a photosensitive drum with a protective layer, this protective layer is used for protecting the photoconductive layer, improving the mechanical strength of the photosensitive drum, improving the dark attenuation characteristic, or applying to a specific electrophotographic process, It is provided for the purpose such as.

Some typical other holding members will be described below. (1) The electrostatic image formed on the electrophotographic photosensitive member is transferred to another image holding member and developed for the purpose of improving the reusability of the electrophotographic photosensitive member, and then the toner image is transferred to the recording member. You. (2) As another electrophotographic process for forming an electrostatic image on another image holding member in correspondence with the electrostatic image formed on the electrophotographic photosensitive member, a screen-shaped electron having a large number of fine openings is used. An electrostatic image is formed on a photographic photoreceptor by a predetermined electrophotographic process, and a corona charging process is performed on another image holding member through the electrostatic image, thereby modulating the corona ion flow to form an electrostatic image. By forming it on another image holding member,
A process of developing the toner and transferring it to a recording medium to form a final image may be used. (3) According to another electrophotographic process, the toner image formed on the electrophotographic photoreceptor or other image holding member is not directly transferred to a recording medium, but is transferred to another image holding member, and then this image is formed. The toner image is transferred and fixed from the holding member to the recording medium. This process is particularly effective for forming a color image or high-speed copying. Many recording media are generally flexible, such as paper and film.
Therefore, rather than transferring the three-color image to the recording medium while accurately aligning the three-color image, the three-color image is transferred to an image holding member that can be formed of a material that hardly deforms,
Transferring the image to the recording medium at a time produces a more accurately aligned color image. In addition, it is effective to transfer a toner image to a recording medium via an image holding member also for speeding up copying. (4) As another process, an electric signal is applied to the multi-needle electrode to form an electrostatic image corresponding to the electric signal on the surface of the image holding member, and this is developed into an image.

The image holding member used in the electrostatic image forming process as described in (1) to (4) does not require a photoconductive layer.

As an image holding member on which an electrostatic image or a toner image is formed as described above, there are various kinds of electrophotographic photoreceptors whose surface layer is a protective layer or a photoconductive layer, and various types of materials whose surface layer is generally an insulating layer. Is used.

The present invention has the following means.

According to a first aspect of the present invention, there is provided a cylinder and an engaging member which is fitted to and attached to an inner periphery of one end in a longitudinal direction of the cylinder and has a concave portion facing the inner periphery of the end of the cylinder. Have
In the cylindrical member, the end of which is bent toward the concave portion of the engaging member and the end of the cylinder is bent, when the end of the cylinder is bent, the periphery of the cylindrical end to be bent is a cylinder. A cylindrical member characterized in that the cylindrical end is bent while being pressed and held from the outer periphery.

A second invention according to the present application is the cylindrical member according to the first invention, wherein the cylinder is made of a plastic metal material.

A third invention according to the present application is the cylindrical member according to the first or second invention, wherein the engagement member is formed of a synthetic resin molded product.

According to a fourth aspect of the present invention, there is provided an electrophotographic image forming apparatus for forming an image on a recording medium, comprising: an electrophotographic photosensitive drum; and processing means for acting on the electrophotographic photosensitive drum. An electrophotographic photosensitive drum used in a process cartridge detachable from an apparatus main body, comprising: a cylinder having a photosensitive layer on a surface; A drum flange provided with a concave portion facing the inner periphery of the drum, wherein the circumference is bent at an end toward the concave portion of the drum flange, and the drum flange is attached to the electrophotographic photosensitive drum. An electrophotographic photosensitive drum characterized in that when bending an end of a cylinder, the cylinder end is bent while the periphery of the bent end of the cylinder is pressed and held from the outer periphery of the cylinder.

According to a fifth aspect of the present invention, in the electrophotographic photosensitive drum according to the fourth aspect, the material of the cylinder is aluminum, aluminum alloy, iron, ferro-alloy, or copper alloy. is there.

A sixth invention according to the present application is characterized in that the drum flange is an integrally molded product, and the material of the drum flange is polyacetal, polycarbonate containing polytetrafluoroethylene, polyamide, or polyethylene. An electrophotographic photosensitive drum according to a fourth aspect.

According to a seventh aspect of the present invention, there is provided a process cartridge detachable from an apparatus main body of an electrophotographic image forming apparatus, comprising: a. A cylinder having a photosensitive layer on the surface of the cylinder and a drum flange fitted and attached to the inner periphery of one end in the longitudinal direction of the cylinder and provided with a concave portion facing the inner periphery of the end of the cylinder; An electrophotographic photosensitive drum having an end bent toward the recess of the drum flange and having the drum flange attached thereto; b. A process means for acting on the electrophotographic photosensitive drum.

An eighth invention according to the present application is the process cartridge according to the seventh invention, wherein the material of the cylinder is aluminum, aluminum alloy, iron, ferro-alloy, or copper alloy.

A ninth invention according to the present application is characterized in that the drum flange is an integrally molded product, and the material of the drum flange is polyacetal, polycarbonate containing polytetrafluoroethylene, polyamide, or polyethylene. A process cartridge according to a seventh or eighth invention.

According to a tenth aspect of the present invention, in the process cartridge, a charging unit, a developing unit or a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is attached to and detached from an image forming apparatus main body. A process cartridge according to any one of the seventh to ninth aspects of the invention, which is enabled.

According to an eleventh aspect of the present invention, in the process cartridge, at least one of a charging unit, a developing unit, and a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge and attached to and detached from an image forming apparatus main body. A process cartridge according to any one of the seventh to ninth aspects of the invention, which is enabled.

According to a twelfth aspect of the present invention, the process cartridge is any one of the seventh to ninth aspects in which at least the developing means and the electrophotographic photosensitive member are integrally formed into a cartridge and can be attached to and detached from the apparatus main body. A process cartridge according to one aspect of the present invention.

[0026]

2. Description of the Related Art An electrophotographic image forming apparatus using an electrophotographic image forming system selectively exposes an electrophotographic photosensitive drum uniformly charged by a charging means in accordance with image information to form a latent image. Form. Then, the latent image is developed by a developing unit using toner to form a toner image. Thereafter, the toner image formed on the electrophotographic photosensitive drum is transferred to a recording medium by a transfer unit to form an image.

Conventionally, in an image forming apparatus using an image forming process, an electrophotographic photosensitive drum and process means acting on the electrophotographic photosensitive drum are integrally formed into a cartridge, and this cartridge is mounted on the main body of the image forming apparatus. A detachable process cartridge system is employed. According to this process cartridge system, the maintenance of the apparatus can be performed by the user himself without relying on a service person, so that the operability can be remarkably improved. Therefore, this process cartridge system is widely used in image forming apparatuses.

In such a process cartridge, the electrophotographic photosensitive drum is connected to a driving device of the apparatus main body.

Here, various methods have been considered in order to rotate the electrophotographic photosensitive drum. As one of the methods, as described in JP-A-62-65049, a pin fixed on the side of a gear provided on the image forming apparatus main body is attached to the side of a gear provided on the photosensitive drum. This is a method in which the photosensitive drum is rotated by being fitted into the provided concave portion.

As another method, as described in Japanese Patent Application Laid-Open No. 63-4252, a method of fitting a helical gear provided in an image forming apparatus main body to rotate a photosensitive drum. is there.

The electrophotographic photoreceptor drum has an end engaging member such as a drum gear for rotating the photoreceptor drum and a drum flange bonded to both ends of a cylinder having a surface coated with a photosensitive conductive material with an adhesive. Or press-fitted into a drum cylinder and joined to the cylinder.

As a method of bonding, an appropriate amount of adhesive is applied to a portion where the gear flange is inserted into the cylinder, and after fitting,
Until the adhesive was completely cured, it was stored in a place (environment) that would not be affected by temperature and humidity, and completely cured.
As an adhesive used for bonding, an instant adhesive or
Adhesive primers, anaerobic adhesives and the like are mainly used, and they are appropriately used depending on the use, purpose, required strength and the like.

Further, there is a method in which a cylindrical end portion is bent at a plurality of positions, and the bent portion is engaged with a concave portion of the end engaging member. This method uses a kind of plastic deformation in which the cylindrical end is bent and cut into the recessed part of the flange and joined together, so even in an environment where there is a temperature change such as thermal shock (heat cycle). Has a stable and strong bonding force. Furthermore, since bonding can be performed instantaneously, a drying time such as adhesive bonding is not required, and workability is extremely good.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a case where a photosensitive drum is used as a cylindrical member will be described with reference to the drawings.

FIG. 1 is a sectional view of a photosensitive drum according to the present invention. In the figure, the photosensitive drum 7 is connected to an end of a drum cylinder 7d, and has a gear flange 16 provided as a drum flange for supporting and rotating the photosensitive drum 7. The cylindrical fitting portion 16b of the gear flange 16 and the hollow cylindrical drum cylinder 7d is provided with a concave portion 16g in the radial direction. The drum cylinder 7d made of an aluminum alloy has a photosensitive layer 7b of a photoconductive layer coated with a photosensitive substance on its surface, and is fitted with a fitting portion 16b of the gear flange 16 with a predetermined fitting tolerance. The recess 16g has a rectangular cross section perpendicular to the radial direction, and two opposing sides thereof are parallel to a plane perpendicular to the axis of the gear flange 16.

In the assembled state, the end surface 7 of the drum cylinder 7d
"e" is in contact with the side surface 16e of the gear flange 16, and is bent so as to cut a part of the cylindrical end in parallel with the axial direction to form a bent cut portion 7f. This bent cut portion 7f fits in the concave portion 16g in the circumferential direction, and
g is pressed against the caulking receiving surface 16f perpendicular to the axis. A caulking flank 1 facing the caulking receiving surface 16f of the recess 16g.
6d is on the same plane as the side surface 16e of the gear flange 16 in this example.

FIG. 2 is a cross-sectional view showing the process of bending and cutting off the end of the drum, which best illustrates the features of the present invention.
(A) is the figure seen from the upper surface, (b) is AA sectional drawing of (a). FIG. 3 is a three-dimensional perspective view showing a step of bending and cutting off the end of the drum.

First, the gear flange 16 and the photosensitive drum 7
1 with the end of the drum cylinder 7d provided in the gear flange 16
The butting tool 23 for entering, contacting, bending and shearing towards 6g will be described.

The abutment tool 23 has a contact surface 23 that contacts the side surface 16e of the gear flange 16 and the caulking relief surface 16d.
a. Bending cut 7 with this contact surface 23a
When f is formed, it is desirable that the gear flange side surface 16e and the caulking flank 16d which receive the reaction force of the bending stress and the shear stress generated simultaneously have a large area. Otherwise, when the gear flange 16 is made of a synthetic resin, the gear flange 16 may be damaged.

The tool tip 23 is positioned against the contact surface 23a.
bending action portion 23 at an angle α (about 30 °) from b
By providing c, the tool end is formed, and the cross section of the tool handle 23d is substantially a square having the same width as the circumferential width of the cross section of the recess 16g. The cutting blade is the bending action part 23
This is the corner between c and the side that intersects it. The cutting edge angle between the bending action portion 23c and the side surface following the bending action portion 23c has a 90 ° or positive rake angle. The material of the butting tool 23 is a cemented carbide or tool steel.

Next, the process of assembling the cylindrical member will be described.

The gear flange 16 and the drum cylinder 7d are fitted along the outer diameter of the fitting portion 16b of the gear flange 16.
After this fitting, the end face 7e of the drum cylinder 7d and the side face 16e of the gear flange 16 are pressed and held by a jig (not shown). At this time, the fit between the gear flange 16 and the drum cylinder 7d is preferably such that there is no play between the two and there is no deformation with respect to the outer diameter of the drum cylinder 7d. More specifically, the clearance between the gear flange 16 and the drum cylinder 7d is preferably about 0 to 10 μm.

Next, after the gear flange 16 and the drum cylinder 7d are fitted, the pressing member 30 advances from the outer periphery of the drum cylinder 7d toward the drum cylinder 7d, and presses the end of the drum cylinder 7d at a predetermined pressure. Hold under pressure. The pressure member 30 is provided in the opposite direction, contacts the outer peripheral surface of the end of the drum cylinder 7d, and uniformly presses and retains the outer peripheral surface within a range that does not damage or deform the outer peripheral surface. The pressure member 30 is provided with an entrance 30a so that the abutment tool 23 can enter, and the drum cylinder 7d
After the pressure is held, the butting tool 23 is
a toward the center of the drum cylinder 7d.
Bend off the end.

After the pressing member 30 presses and holds the drum cylinder 7d, the butting tool 23 contacts the outer peripheral surface of the drum cylinder 7d from two circumferential positions of the gear flange 16. At this time, the height of the contact surface 23a of the butting tool 23 is
d is the same height as the position of the end face 7e, and the fitting portion 16 of the gear flange 16 fitted inside the drum cylinder 7d.
b, the width of the concave portion 16g and the width of the tip of the abutment tool 23 have the same width, and the abutment tool 23 is straightened in the radial direction of the gear flange 16 in a state where there is no deviation in the positional relationship. It moves and comes into contact with the outer peripheral portion of the drum cylinder 7d.
Then, when the butting tool 23 enters the gear flange 16 from the contact point with a predetermined entry amount,
The drum cylinder bends from the end of the drum cylinder 7d along the surface shape of the bending action portion 23c of the butting tool 23, and further advances as soon as the drum cylinder 7d moves along the corner of the concave portion 16g provided in the fitting portion 16b of the gear flange 16. The end of the 7d is sheared in the form of parallel cuts in the axial direction, and the end of the drum cylinder 7d that is partially bent is closely adhered to the caulking receiving surface 16f of the recess 16g and the surface that intersects the caulking receiving surface 16f. The gear flange 16 and the drum cylinder 7d are coupled together.

At this time, more preferably, the butting tool 2
By making 3 enter, the end of the drum cylinder 7d is completely sheared, and the sheared surface is in a state of being in close contact with the shape of the recess 16g. In this state, the sheared surface of the partially bent end portion is tightly coupled to the concave portion 16g provided in the fitting portion 16b of the gear flange 16, so that the rotational direction of the photosensitive drum 7 and It is possible to maintain a higher coupling force without causing play, loosening, and the like in the axial direction.

The process for connecting the cylinder and the end engaging member according to the present invention has been described above. Next, FIG. 4 shows a pressure holding member 30 which presses and holds the cylindrical end which is a feature of the present invention. It will be described using FIG.

The pressure member 30 is connected to a drive mechanism such as a hydraulic or air cylinder (not shown),
Direction). 7d drum cylinder
When the end portion is pressurized, it can be pressurized by linearly moving toward the center of the drum cylinder 7d. The pressurizing member 30 is arranged to face the drum cylinder 7d in two divided portions with a center therebetween, and a slight gap t exists between the two pressurizing members 30. This gap t is a pressurization allowance. When the end of the drum cylinder 7d is pressurized, the pressurizing member 30 is advanced toward the center of the cylinder within the range of the pressurization allowance t, so that the end of the drum cylinder 7d is pressurized. Pressing force can be controlled.

The material of the pressing member 30 is a drum cylinder 7d.
The material is not particularly limited as long as the material can suppress the deformation force that bulges outward when the end is bent. However, from the results of the study of the present invention, a relatively strong metal material is suitable.
More specifically, examples include iron, tool steel (SK material, SKD material), stainless steel, aluminum alloy, and carbide.

When a cylindrical member such as a photosensitive drum having a photosensitive layer on its surface or a cylindrical member whose surface is not to be scratched or dents is held, a holding layer of the pressing member 30 is provided. 30b may be provided. The holding layer 30b is made of a material that does not scratch or dent when the holding cylindrical end is pressed. For example, a synthetic resin material (POM,
PC, PBT, PET, etc.), hard rubber, urethane rubber and the like.

The entrance 3 of the abutting tool 23 is inserted into the pressing member 30 so that the abutting tool 23 can pass through the pressing member 30 and bend the end of the drum cylinder 7d.
0a is provided. When the end portion of the drum cylinder 7d is uniformly pressurized and held over the entire circumference, the butting tool 23 passes through the entrance 30a, and after the tip of the butting tool 23 comes into contact with the surface of the drum cylinder 7d, a predetermined amount of approaching is performed. And bends the end of the drum cylinder 7d.

It is important that the size of the entrance 30a is the minimum size necessary for the butting tool 23 to pass through the pressing member 30 and bend the end of the drum cylinder 7d. The reason is that if the entrance 30a is expanded more than necessary, the area of the pressing member 30 pressing the end portion of the drum cylinder 7d decreases, and effective pressing cannot be performed. Therefore, it is desirable that the cross-sectional shape of the entrance 30a on the exit side of the butting tool 23 be the same shape and the same size as the concave portion 16g provided in the drum flange.

In the present embodiment, the pressing member 30
Is divided into two parts in the direction opposite to the drum cylinder 7d. However, the present invention is not particularly limited to such a configuration.
The pressurizing member 30 may be configured to be divided into multiple directions such as six.

The above is the description of the pressure holding member 30.
The present invention is not limited to the above-described configuration, and any other method may be used as long as the end can be uniformly pressed and held without deforming the end of the drum cylinder 7d.

Next, the operation of the pressure holding member for pressing and holding the cylindrical end will be described with reference to FIG. In FIG. 5, (a) shows the process of bending and cutting connection when the cylinder end is not pressed and held, and (b) shows the bending and cutting connection when the cylinder end is pressed and held according to the present invention. FIG.
In the conventional case (a), the butting tool 23 is viewed microscopically.
When this is abutted against the end of the drum cylinder 7d and bent, the periphery of the end of the drum cylinder 7d is deformed as shown by 7g in FIG. This is because the part cut by the butting tool 23 is deformed inside the end engaging member, and the other surrounding parts are deformed outside by releasing the internal stress of the drum cylinder 7d. The edges tend to bulge. Due to this deformation, there is a deformation region L in which the roundness is deteriorated in a range of several millimeters from the end of the drum cylinder 7d. The deformation area here is defined as follows.

The deformation region L is formed by bending the cylindrical end into the concave portion of the end engaging member so as to connect the end engaging member to the cylinder. Refers to a region in the axial direction (longitudinal direction) of the cylinder, which worsens the above.

When the deformed area L reaches the position of the spacer roller 10i in contact with the developing roller 10d, the rotation behavior of the developing roller 10d becomes non-uniform, and this may appear as image density unevenness. The deformation area L is greatly affected by the thickness of the drum cylinder 7d, the width of the butting tool 23, the angle α, the amount of approach, and the like. According to our experimental results, the drum cylinder 7d
As the wall thickness increases, the bonding force increases, but the deformation region tends to increase. It is also known that the larger the amount of the abutting tool 23 entering, the larger the coupling force is, but the larger the deformation area is. Compared to bonding and the like, bonding by such bending and cutting has the advantage that the bonding force can maintain a stable high strength even during a heat cycle and can be bonded instantly by a very simple method,
There was also a disadvantage that the area around the bent section was deformed.
Therefore, in the past, the coupling conditions were determined in consideration of the balance between the coupling force and the deformation amount. However, in order to obtain a higher definition image, a highly accurate photosensitive device in which such a deformation region L is eliminated as much as possible. A cylindrical member such as a body drum and a developing sleeve is required.

Therefore, in the present invention, as shown in FIG. 5B, by pressing and holding the end portion of the drum cylinder 7d by the above-described pressing member 30, the deformation force swelling outward generated at the time of bending and cutting is suppressed, and the deformation is performed. The area can be minimized. The following advantages can be obtained by minimizing the deformation region.

Conventionally, the deformation region L is formed by the spacer roller 10i.
(See FIG. 18), the rotational behavior of the developing roller 10d is adversely affected.
It was necessary to extend the entire length of d.

However, as shown in the present invention, the pressing member 30
Since the deformation region L can be minimized by bending while holding the end portion of the drum cylinder 7d under pressure, the length of the drum cylinder 7d can be shortened, and the process cartridge is greatly reduced in size (downsizing). You can contribute.

Hereinafter, an electrophotographic image forming apparatus and a process cartridge to which the embodiment of the present invention is applied will be described in detail with reference to FIG.

In the following description, the short direction of the process cartridge B is the direction in which the process cartridge B is attached to and detached from the apparatus main body 13, and coincides with the transport direction of the recording medium. The longitudinal direction of the process cartridge B is a direction (direction substantially perpendicular to) that intersects with the direction in which the process cartridge B is attached to and detached from the apparatus main body 13, is parallel to the surface of the recording medium, and is a conveying direction of the recording medium. The direction intersects (substantially orthogonal). Further, the left and right of the process cartridge B are right or left when the recording medium is viewed from above according to the transport direction of the recording medium.

FIG. 6 is an explanatory view of a configuration of an electrophotographic image forming apparatus (laser beam printer) to which the embodiment of the present invention is applied, and FIG. 7 is an external perspective view thereof. 8 to 1
3 is a drawing related to a process cartridge to which the embodiment of the present invention is applied. 8 is a side sectional view of the process cartridge, FIG. 9 is an external perspective view schematically showing the external appearance, FIG. 10 is a right side view thereof, FIG. 11 is a left side view thereof, and FIG. FIG. 13 is a perspective view when the process cartridge is turned over and viewed from above. Further, in the following description, the upper surface is a surface located above when the process cartridge B is mounted on the apparatus main body 13, and the lower surface is a surface located below.

(Electrophotographic Image Forming Apparatus A and Process Cartridge B) First, a laser beam printer A as an electrophotographic image forming apparatus to which the embodiment of the present invention is applied will be described with reference to FIGS. FIG.
2 shows a side cross section of the process cartridge B.

As shown in FIG. 6, the laser beam printer A forms an image on a recording medium (for example, recording paper, OHP sheet, cloth, etc.) by an electrophotographic image forming process. Then, a toner image is formed on a drum-shaped electrophotographic photosensitive member (hereinafter, referred to as a photosensitive drum).
More specifically, the photoconductor drum is charged by a charging unit, and then the photoconductor drum is irradiated with a laser beam corresponding to the image information from the optical unit to form a latent image on the photoconductor drum according to the image information. Then, the latent image is developed by a developing unit to form a toner image. Then, in synchronization with the formation of the toner image, the recording medium 2 set in the sheet feeding cassette 3a is picked up by the pickup roller 3b and the conveying roller pair 3
It is reversed and conveyed by c, 3d and a pair of registration rollers 3e. Next, the toner image formed on the photosensitive drum 7 of the process cartridge B is transferred to the recording medium 2 by applying a voltage to a transfer roller 4 as a transfer unit. Thereafter, the recording medium 2 to which the toner image has been transferred is conveyed to the fixing unit 5 by the conveyance guide 3f. The fixing unit 5 includes a driving roller 5c and a fixing roller 5 including a heater 5a.
b. Then, heat and pressure are applied to the passing recording medium 2 to fix the transferred toner image. Then, the recording medium 2 is conveyed by discharge rollers 3g, 3h, and 3i, and is discharged to a discharge tray 6 through a reversing path 3j. The discharge tray 6 is provided on the upper surface of the apparatus main body 13 of the image forming apparatus A. It is also possible to operate the swingable flapper 3k and discharge the recording medium 2 by the discharge roller pair 3m without passing through the reversing path 3j. In the present embodiment, the pickup roller 3b, the transport roller pair 3c, 3d, the registration roller pair 3e, the transport guide 3
f, discharge rollers 3g, 3h, 3i and discharge roller pair 3m
The transport means 3 is constituted by these.

On the other hand, as shown in FIGS. 8 to 13, the process cartridge B has a photosensitive layer 7b (see FIG. 16).
Is rotated, and the surface thereof is uniformly charged by applying a voltage to a charging roller 8 as charging means. Next, a laser beam corresponding to the image information from the optical system 1 is irradiated onto the photosensitive drum 7 through the exposure opening 1e to form a latent image. Then, the latent image is developed by developing means 10 using toner. That is, the charging roller 8 is provided in contact with the photosensitive drum 7 and charges the photosensitive drum 7. The charging roller 8 is driven and rotated by the photosensitive drum 7. The developing unit 10 supplies toner to a developing area of the photosensitive drum 7 to develop a latent image formed on the photosensitive drum 7. The optical system 1 is
It has a laser diode 1a, a polygon mirror 1b, a lens 1c, and a reflection mirror 1d.

Here, the developing means 10 sends out the toner in the toner container 10A to the developing roller 10d by the rotation of the toner sending member 10b. Then, while rotating the developing roller 10 d having a fixed magnet therein, a toner layer provided with a triboelectric charge by the developing blade 10 e is formed on the surface of the developing roller 10 d, and the toner is supplied to the developing area of the photosensitive drum 7. . Then, the toner image is transferred to the photosensitive drum 7 in accordance with the latent image, thereby forming a toner image and visualizing the toner image. Here, the developing blade 10e regulates the amount of toner on the peripheral surface of the developing roller 10d and applies a triboelectric charge. A toner stirring member 10f for circulating the toner in the developing chamber is rotatably mounted near the developing roller 10d.

Then, a voltage having a polarity opposite to that of the toner image is applied to the transfer roller 4 to transfer the toner image formed on the photosensitive drum 7 to the recording medium 2.
1 removes the residual toner on the photosensitive drum 7.
Here, the cleaning means 11 scrapes off the toner remaining on the photoconductor drum 7 by an elastic cleaning blade 11a provided in contact with the photoconductor drum 7 and collects it in the waste toner reservoir 11b.

In the process cartridge B, a toner frame 12a having a toner container (toner storage section) 10A for storing toner and a developing frame 12b holding the developing means 10 such as a developing roller 10d are connected. The photosensitive drum 7 and the cleaning blade 11a
Cleaning means 11 and a cleaning frame 12c to which the charging roller 8 is attached. The process cartridge B is detachable from the image forming apparatus main body 13 by an operator.

The process cartridge B is provided with an exposure opening 1e for irradiating the photosensitive drum 7 with light corresponding to image information and a transfer opening 12n for facing the photosensitive drum 7 to the recording medium 2. is there. More specifically, the exposure opening 1e is provided in the cleaning frame 12c, and the transfer opening 12n is formed between the developing frame 12b and the cleaning frame 12c.

Next, the configuration of the housing of the process cartridge B according to the present embodiment will be described.

The process cartridge B shown in the present embodiment has a housing in which a toner frame 12a and a developing frame 12b are connected, and a cleaning frame 12c is rotatably connected thereto. This is a cartridge that houses the charging roller 8, the developing unit 10, the cleaning unit 11, and the like. The process cartridge B is inserted into the image forming apparatus main body 1.
3 is detachably mounted on the cartridge mounting means provided in 3.

(Structure of Housing of Process Cartridge B) The process cartridge B according to this embodiment is
As described above, the housing is configured by combining the toner frame 12a1, the developing frame 12b, and the cleaning frame 12c. Next, the configuration will be described.

As shown in FIG. 8, the toner frame 12a
, A toner feeding member 10b is rotatably mounted. A developing roller 10d and a developing blade 10e are attached to the developing frame 12b.
In the vicinity of 0d, a toner stirring member 10f for circulating the toner in the developing chamber is rotatably mounted. As shown in FIG. 8, a developing roller 10d is provided on the developing frame 12b.
The antenna rod 10h is attached substantially in parallel with the developing roller 10d so as to face the longitudinal direction of the developing roller 10d. The toner frame 12a and the developing frame 12b are welded (in this embodiment, ultrasonic welding) to constitute a developing unit D (see FIG. 18) as an integrated second frame.

When the process cartridge B is removed from the image forming apparatus main body 13, the drum shutter member 48 that covers the photosensitive drum 7 and protects the photosensitive drum 7 from being exposed to light for a long time or from contact with foreign matter is used as a toner developing unit. Attached to.

As shown in FIGS. 8 and 17, the photosensitive drum 7, the charging roller 8 and the cleaning means 11 are attached to the cleaning frame 12c, and a cleaning unit C as a first frame (see FIG. 17). ).

The process cartridge B is constituted by connecting the developing unit D and the cleaning unit C to each other by a round pin connecting member 22 so as to be rotatable. That is, as shown in FIG. 18, a circular turning hole 19a is provided at the tip of an arm portion 19 formed on both sides in the longitudinal direction (axial direction of the developing roller 10d) of the developing frame 12b in parallel with the developing roller 10d. (See FIG. 18). On the other hand, concave portions 21 for entering the arm portions 19 are provided at two places on both sides in the longitudinal direction of the cleaning frame 12c (see FIG. 17). This recess 2
1. The arm 19 is inserted into the mounting member 1 and the coupling member 22 is press-fitted into the mounting hole 12c5 of the cleaning frame 12c, and is fitted into the pivot hole 19a at the end of the arm 19 and further press-fitted into the inner hole 12c5. Accordingly, the developing unit D and the cleaning unit C are rotatably connected around the connecting member 22. At this time, the compression coil spring 22a inserted into and attached to the dowel (not shown) standing upright at the root of the arm portion 19 is engaged with the concave portion 2 of the cleaning frame 12c.
By pressing the developing frame 12b downward by the compression coil spring 22a against the upper wall of the first developing roller 10d, the developing roller 10d is reliably pressed against the photosensitive drum 7. The upper wall of the concave portion 21 of the cleaning frame 12c is inclined so that the compression coil spring 22a gradually increases the compression from the non-compression state when the developing unit D and the cleaning unit C are assembled. Therefore, as shown in FIG. 12, the developing roller 1d is provided at both longitudinal ends of the developing roller 10d.
By attaching the spacer roller 10i having a diameter larger than 0d, the roller 10i is pressed against the photosensitive drum 7, and the photosensitive drum 7 and the developing roller 10d face each other at a constant interval (about 300 μm). Therefore,
The developing unit D and the cleaning unit C are connected to the connecting member 2.
2 can rotate around each other, and the elastic force of the compression coil spring 22a can maintain the positional relationship between the peripheral surface of the photosensitive drum 7 and the peripheral surface of the developing roller 10d.

(Structure of Guide Means for Process Cartridge B) Next, guide means for attaching and detaching the process cartridge B to and from the apparatus main body 13 will be described. This guide means is shown in FIGS.
FIG. 14 shows the process cartridge B in the main assembly 13 of the apparatus.
(Developing unit D)
FIG. 6 is a left perspective view (when viewed from the side). FIG. 15 is a perspective view of the right side.

As shown in FIGS. 9, 10, 11 and 12, guide means are provided on both sides of the cleaning frame 12c as guides for attaching and detaching the process cartridge B to and from the apparatus main body 13. Have been. The guide means is constituted by cylindrical guides 9aR and 9aL as positioning guide members, and detent guides 9bR and 9bL as guide members as posture holding means at the time of attachment and detachment.

The cylindrical guide 9aR is a hollow cylindrical member, and the detent guide 9bR is integrally formed with the cylindrical guide 9aR, and projects substantially radially integrally from the circumference of the cylindrical guide 9aR. I have. Cylindrical guide 9
aR is integrally provided with a mounting flange 9aR1. Thus, the cylindrical guide 9aR, the detent guide 9
bR, right guide member 9 having mounting flange 9aR1
R is fixed by screwing a small screw 9aR2 into the cleaning frame 12c through a small screw hole of the mounting flange 9aR1. The detent guide 9bR of the right guide member 9R fixed to the cleaning frame 12c is disposed on the side surface of the developing frame 12b so as to extend to the side of the developing holder 41 fixed to the developing frame 12b.

As shown in FIG. 11, the enlarged diameter portion 7a2 of the drum shaft 7a is fitted into the hole 9k1 (see FIG. 16) of the cleaning frame 12c. Then, it is fitted into a positioning pin 9c protruding from the side surface of the cleaning frame 12c and is stopped from rotating.
A cylindrical guide 9aL protrudes outward (toward a direction perpendicular to the plane of the paper of FIG. 11) from a flat flange 29 fixed to the cylindrical guide 9aL. The fixed drum shaft 7a rotatably supports the spur gear 25b fitted on the photosensitive drum 7 inside the flange 29 (see FIG. 16). The cylindrical guide 9aL and the drum shaft 7a are coaxial. The flange 29 and the cylindrical guide 9aL
The drum shaft 7a is integrally or integrally made of a metal material such as an iron material.

As shown in FIG. 11, the cylindrical guide 9aL
The detent guide 9bL, which is slightly separated from the cylindrical guide 9aL in a substantially radial direction of the cylindrical guide 9aL,
c so that the cleaning frame 12 projects sideways from
c is integrally formed. This detent guide 9bL
However, in the portion where the flange 29 interferes, the flange 29 is cut out, and the protrusion height of the detent guide 9bL to the side is such that the top surface substantially coincides with the top surface of the detent guide 9bL. The detent guide 9bL is used for the developing frame 12
b and extends to the side of the developing roller bearing box 9v. As described above, the left guide member 9L is provided as a separate member separately from the metal cylindrical guide 9aL and the synthetic resin detent guide 9bL.

Next, the regulating contact portion 9j provided on the upper surface 9i of the cleaning unit C will be described. Here, the upper surface means that the process cartridge B is
3 is a surface that is located above when mounted on the device.

In this embodiment, as shown in FIGS. 9 to 12, the right and left ends 9p and 9q of the upper surface 9i of the cleaning unit C in a direction perpendicular to the mounting direction of the process cartridge are respectively regulated. A contact portion 9j is provided. The restriction contact portion 9j defines the position of the process cartridge B when the process cartridge B is mounted on the image forming apparatus main body 13. That is, when the process cartridge B is mounted on the apparatus image forming main body 13, the fixing member 26 provided on the image forming apparatus main body 13 is used.
(See FIGS. 14 and 15). The regulating contact portion 9j contacts the process cartridge B, and the process cartridge B is brought into cylindrical guides 9aR and 9a.
A rotation position about aL is defined.

Next, the guide means on the image forming apparatus main body 13 side will be described. Opening / closing cover 1 of image forming apparatus main body 13
7 is rotated counterclockwise in FIG. 7 around the shaft 14a, the upper part of the image forming apparatus main body 13 is opened, and the mounting portion of the process cartridge B is seen as in FIGS. When viewed from the mounting direction of the process cartridge B on the left and right inner walls of the image forming apparatus main body 13 from the opening portion where the opening / closing cover 14 is opened, the guide members 15 (15R, 15L) are provided on the left side as shown in FIG. ) Are provided respectively.

As shown in the figure, the guide member 15 has guide portions 15a and 15c which are obliquely provided so as to be lowered forward as viewed from the arrow X in the insertion direction of the process cartridge B, respectively.
Anti-circular positioning U-shaped grooves 15b, 15d are provided which are respectively connected to the guide portions 15a, 15c, and into which the cylindrical guides 9aR, 9aL of the process cartridge B are fitted.
The lower peripheral wall of each of the U grooves 15b and 15d has an anti-cylindrical shape. The center of the U-grooves 15b and 15d is located at the center of the process cartridge B when the process cartridge B is mounted on the apparatus main body 13.
Does not coincide with the center line connecting the centers of the cylindrical guides 9aR and 9aL. In other words, the cylindrical guide 9aL is just fitted into the U groove 15b, and the position on the non-drive side of the photosensitive drum 7 is determined. However, when the cylindrical guide 9aR is fitted into the U groove 15d, the cylindrical guide 9aR is simply supported. The shaft joint is separated from the U-shaped groove 15d by the centering action of a shaft coupling described later.

The width of each of the guide portions 15a and 15c is such that the cylindrical guide 9a is viewed from the attaching / detaching direction of the process cartridge B.
R and 9aL have a width that allows loose fit. Cylindrical guide 9a
The detent guides 9bR and 9bL each having a narrower width than the diameter of R and 9aL fit loosely, but the rotation of the cylindrical guides 9aR and 9aL and the detent guides 9bR and 9bL is restricted by the guide parts 15a and 15c. The process cartridge B is mounted while maintaining a certain range of posture. When the process cartridge B is mounted on the image forming apparatus main body 13, the cylindrical guides 9aR and 9aL of the process cartridge B
The cleaning frame 12c of the process cartridge B fits into the positioning grooves 15b and 15d of the R and 9L.
The right and left regulating contact portions 9j are fixed members 2 of the apparatus main body 13.
6.

In the process cartridge B described above, if the center lines of the cleaning unit C and the developing unit D, which are the center lines connecting the centers of the cylindrical guides 9aR and 9aL, are kept horizontal, the developing unit D will be in the cleaning unit C side.
The weight distribution is such that a momentary moment greater than the side is generated.

To mount the process cartridge B on the image forming apparatus main body 13, the concave portion 47 of the toner frame 12a is used.
Each of the side and lower ribs 47a is grasped with one hand, and the cylindrical guides 9aR and 9aL are inserted into the guide portions 15a and 15c of the cartridge mounting portion of the image forming apparatus main body 13, respectively.
Subsequently, the process cartridge B is lowered forward as viewed from the insertion direction, and the detent guides 9bR and 9bL are inserted into the guide portions 15a and 15c of the image forming apparatus main body 13. The cylindrical guides 9aR and 9aL and the detent guides 9bR and 9bL of the process cartridge B advance to the back side along the guide portions 15a and 15c of the image forming apparatus main body 13, and the cylindrical guides 9aR and 9aL of the process cartridge B form the image. When the positioning grooves 15b and 15d of the device main body 13 are reached,
These cylindrical guides 9aR, 9aL are provided with positioning grooves 15b,
The process cartridge B is seated at the position 15d by the gravity of the process cartridge B. Since the center line connecting the centers of the cylindrical guides 9aR and 9aL is the center line of the photosensitive drum 7, the position of the photosensitive drum 7 is roughly determined with respect to the image forming apparatus main body 13. The position of the photosensitive drum 7 with respect to the apparatus main body 13 is finally determined in a state where the shaft coupling is connected.

In this state, the fixed member 26 of the image forming apparatus main body 13 and the regulating contact portion 9j of the process cartridge B are
Has a slight gap. Here, process cartridge B
Is released, the process cartridge B descends on the developing unit D side around the cylindrical guides 9aR and 9aL, the cleaning unit C rises, and the regulating contact portion 9j of the process cartridge B is moved to the image forming apparatus. The process cartridge B contacts the fixed member 26 of the main body 13 and is mounted on the main body 13 of the image forming apparatus. Thereafter, the opening / closing cover 14 is closed by turning clockwise about the shaft 14a in FIG.

The process cartridge B is detached from the apparatus main body 13 in the opposite manner as described above. The open / close cover 14 of the apparatus main body 13 is opened, and the upper and lower ribs 47a forming the handle of the process cartridge B are put on the upper and lower hands 47a and lifted. Then, the cylindrical guide 9aR,
9aL rotates about the positioning grooves 15b and 15d of the apparatus main body 13, and the regulating contact portion 9j of the process cartridge B.
Is separated from the fixed member 26 of the apparatus main body 13. When the process cartridge B is further pulled, the cylindrical guides 9aR, 9a
aL escapes from the positioning grooves 15b and 15d and moves to the guide portions 15a and 15c of the guide members 15R and 15L fixed to the apparatus main body 13, and when the process cartridge B is pulled up as it is, the cylindrical guide 9aR and 9aL, detent guides 9bR, 9b
L moves through the guide portions 15a and 15c of the apparatus main body 13 and rises, whereby the attitude of the process cartridge B is regulated.
3 is taken out of the apparatus body 13 without hitting other parts.

As shown in FIG. 17, the spur gear 25
b is provided at the end of the photosensitive drum 7 opposite to the helical gear 16a in the axial direction. When the process cartridge B is mounted on the apparatus main body 13, the spur gear 25b meshes with a gear (not shown) coaxial with the transfer roller 4 provided on the apparatus main body 13 to rotate the transfer roller 4. The driving force to be transmitted is transmitted from the process cartridge B.

(Shaft Coupling and Driving Configuration) Next, the configuration of a shaft coupling device as a drive transmission mechanism from the image forming apparatus main body 13 to the process cartridge B will be described.

As shown in FIG. 16, a cartridge-side shaft coupling member is provided at one longitudinal end of the photosensitive drum 7 attached to the process cartridge B.
This shaft coupling member has a coupling flange 17 (cylindrical shape) provided on a drum flange 16 fixed to one end of the photoreceptor drum 7. Is formed. The coupling convex shaft 17 is fitted to the bearing 24 and functions as a drum rotation shaft. In this embodiment, the gear flange 16, the coupling convex shaft 17, and the convex portion 17a are provided integrally. The gear flange 16 is integrally provided with a helical gear 16a for transmitting a driving force to the developing roller 10d inside the process cartridge B. Therefore, the gear flange 16 is an integrally molded product having a fitting portion 16b to the drum cylinder 7d, a helical gear 16a, a coupling convex shaft 17, and a convex portion 17a, and has a function of transmitting a driving force. It is a driving force transmission component.

Further, a concave portion 18 fitted with the convex portion 17a is provided.
a is a hole whose cross section is a substantially equilateral triangle and is gradually twisted in the axial direction. The recess 18a rotates integrally with the large gear 34 provided on the apparatus main body 13. Therefore, in the configuration of the present embodiment, the process cartridge B
Is mounted on the apparatus main body 13, and the convex portion 17a and the apparatus main body 1
When the rotational force of the concave portion 18a is transmitted to the convex portion 17a by fitting with the concave portion 18a provided in the third portion 3, the ridge line of the convex portion 17a and each inner surface of the concave portion 18a abut equally, so that the axial centers are mutually aligned. Match. Further, since the concave portion 18a is gradually twisted in the axial direction, a force acts in a direction in which the concave portion 18a draws the convex portion 17a, and the end face of the convex portion 17a is
Abuts the bottom of Thus, the axial position and the radial position of the photosensitive drum 7 integrated with the convex portion 17a in the image forming apparatus main body 13 are stably determined.

The other end of the photosensitive drum 7 has
The drum flange 25 is fixed. A spur gear 25b is integrally formed with the drum flange 25 (see FIG. 16). The drum flange 25 is rotatably fitted to the drum shaft 7a integral with the flange 29 fixed to the cleaning frame 12c.

The process cartridge B is installed in the main assembly 1 of the apparatus.
3, the cylindrical guide 9 aL concentric with the drum shaft 7 a is fitted and positioned in the U groove 15 b (see FIG. 14) of the apparatus main body 13, and is a flat tooth integrally formed with the drum flange 25. The gear 25b meshes with a gear (not shown) that transmits a driving force to the transfer roller 4.

A hollow cylindrical boss 24a concentric with the convex shaft 17 is provided around the convex portion 17a of the coupling convex shaft 17 of the process cartridge B.
2c (see FIGS. 9 and 16). The coupling boss 17a is protected by the boss 24a when the process cartridge B is attached or detached or the like, and is protected from damage or deformation due to external force. Therefore, it is possible to prevent rattling and vibration during coupling driving due to damage to the projection 17a.

The drum flanges 16 and 25 are made of polyacetal.
l), polycarbonate (polycarbonat)
e), polyamide (polyamide) and polybutylene terephthalate (polybutylenenet)
(e.g., elephthalate). However, other materials may be appropriately selected and used.

In the present embodiment, the drum flange 25 is fitted to the drum shaft 7a provided on the cleaning frame 12c (see FIG. 16), and the inner surface of the bearing 24 mounted on the cleaning frame 12c. The photosensitive drum 7 is attached to the cleaning frame 12c of the process cartridge B in a state where the coupling convex shaft 17 is fitted to the photosensitive drum 7. Then, the photosensitive drum 7 rotates around the coupling convex shaft 17 and the drum shaft 7a.

The large gear 34 on the side of the apparatus body 13 is constituted by a helical gear.
7 when the driving force is transmitted from the small helical gear 20 fixed to the shaft 30a of the motor 30 shown in FIG. 7 so as to generate a thrust for moving the coupling concave shaft 18 toward the convex shaft 17. It has teeth with angles. As a result, when the motor 30 is driven during image formation, the coupling concave shaft 18 moves in the direction of the convex shaft 17 due to the thrust, and the engagement between the concave portion 18a and the convex portion 17a is assisted.

A configuration is used in which the concave portion 18a and the convex portion 17a are fitted in conjunction with the closing operation of the opening / closing cover 14 (the description is omitted).

[0102]

【Example】

(Example 1) (1) Production of drum cylinder having photosensitive layer Aluminum drawing cylinder manufactured by Kobe Steel Ltd. (Product name: H6)
3S, a casein ammonia aqueous solution (casein 11.2 g, 28) was placed on an aluminum cylinder having a fitting portion inner diameter: φ62 mm, wall thickness: 1.5 mm, length: 365.5 mm).
% Aqueous ammonia, 222 ml of water) was applied by a dip coating method, and dried to form a subbing layer having a coating amount of 1.0 g / m.

Next, 1 part by weight of aluminum chloride phthalocyanine, butyral resin (trade name, ESLEC B)
M-2: 1 part by weight of Sekisui Chemical Co., Ltd.) and 30 parts by weight of isopropyl alcohol were dispersed by a ball mill disperser for 4 hours. This dispersion was applied on the previously formed undercoat layer by a dip coating method and dried to form a charge generation layer. At this time, the film thickness was 0.3 μm.

Next, 1 part by weight of a hydrazone compound, 1 part by weight of a polysulfone resin (trade name: P1700: manufactured by Union Carbide) and 6 parts by weight of monochlorobenzene were mixed and stirred and dissolved by a stirrer. This liquid was applied on the charge generation layer by a dip coating method, and dried to form a charge transport layer. At this time, the film thickness was 12 μm. (2) Manufacture of gear flange Next, use polyacetal resin (trade name: "Duracon M90
A drum gear flange having a fitting portion outer diameter of φ58.6 mm was manufactured by injection molding of “-02” a copolymer manufactured by Polyplastics Co., Ltd.). The molding conditions at this time are nozzle temperature:
200 ° C, cylinder temperature: 180 ° C at tip, middle 1
70 ° C., rear 160 ° C., injection pressure: 800 kg / cm,
Mold temperature: 60 ° C. for mold and 60 ° C. for core. At the fitting portion of the gear flange, two rectangular hole-shaped concave portions (width 3 mm, height 1 mm, depth 3 mm) were provided in two opposing directions from the center of the gear flange. (3) Coupling of Drum Cylinder and Gear Flange The drum cylinder having the photosensitive layer thus formed was fitted to the drum gear flange.

Then, the end portion of the drum cylinder is pressurized and held at a pressure of 5 kg / mm ² by a pressing member made of bakelite resin for the holding layer and stainless steel for the holder portion. The width of the tip is 3 mm and the angle is 30
°, abutment tool 23 made of material SKD30 is abutted at an infeed amount of 1.5 mm, and the end of the drum cylinder is cut and bent along the shape of the concave portion to produce a photosensitive drum in which a gear flange and a drum cylinder are combined. did.

In order to examine the deformation around the flange connection portion of the photosensitive drum thus obtained, the cylindricity was measured at a position of about 50 mm from the end of the cylinder at intervals of 0.1 mm using a roundness measuring machine ( The measurement was performed using RA-600 manufactured by Mitutoyo Corporation. As a result, the cylindricity was 8 μm.

At this time, the deformation area was 2 mm.

The photosensitive drum thus obtained is mounted on a process cartridge of a laser beam printer manufactured by Canon Inc., and the process cartridge is placed in a high-temperature and high-humidity layer (specifically, a temperature of 32.5 ° C. and a relative humidity of 85%). At 48
After standing for a while, the process cartridge was set in the laser beam printer main body in the same environment, and 10,000 images were intermittently displayed. After image output, the photosensitive drum was removed from the process cartridge, and the joint between the gear flange and the drum cylinder was checked for any effects such as looseness, looseness, and separation due to durability. As a result, a very good image was obtained on the image without problems such as pitch unevenness and fog due to the photosensitive drum. Further, the photoreceptor drum after the endurance was fixed, and the breaking torque strength of the flange was measured with a commercially available torque gauge. As a result, the breaking torque strength was 158 kg-cm.

Example 2 A photosensitive drum was manufactured under the same conditions as in Example 1 except that the pressing force of the pressing member was set to 3 kg / mm ² , and the same measurement and evaluation were performed. The same result as in Example 1 was obtained. The breaking torque strength at that time was 149 kg-cm, the cylindricity at the end of the drum cylinder was 12 μm, and the deformation area was 2.5 mm.

Example 3 A photoreceptor drum was manufactured under the same conditions as in Example 1 except that the pressing force of the pressing member was set to 1 kg / mm ² , and the same measurement and evaluation were performed. The same result as in Example 1 was obtained. The breaking torque strength at that time was 151 kg-cm, the cylindricity of the drum cylinder end was 17 μm, and the deformation area was 3.2 mm.

(Comparative Example 1) Aluminum drawing cylinder manufactured by Kobe Steel Ltd. (product name: H63S, inner diameter of fitting part: φ62 m)
m, wall thickness: 1.5 mm, length: 365.5 mm) on an aluminum cylinder composed of an aqueous ammonia solution of casein (casein 11.2 g, 28% ammonia water 1 g, water 2)
22 ml) was applied by a dip coating method, and dried to form a subbing layer having a coating amount of 1.0 g / m.

Next, 1 part by weight of aluminum chloride phthalocyanine, 1 part by weight of butyral resin (trade name: Eslex BM-2, manufactured by Sekisui Chemical Co., Ltd.) and 30 parts by weight of isopropyl alcohol were dispersed by a ball mill for 4 hours. . This dispersion was applied on the previously formed undercoat layer by a dip coating method and dried to form a charge generation layer.
At this time, the film thickness was 0.3 μm.

Next, 1 part by weight of a hydrazone compound, 1 part by weight of a polysulfone resin (trade name: P1700: manufactured by Union Carbide Co., Ltd.) and 6 parts by weight of monochlorobenzene were mixed and dissolved by stirring with a stirrer. This liquid was applied on the charge generation layer by a dip coating method, and dried to form a charge transport layer. At this time, the film thickness was 12 μm.

A drum cylinder having a photosensitive layer and a polyacetal resin (trade name: “Duracon M”)
90-02 "Polyplastic Co., Ltd. copolymer) produced by injection molding a gear flange (fitting part outer diameter: φ5)
9.02 mm, molding conditions: nozzle temperature: 200 ° C., cylinder temperature: tip 180 ° C., middle 170 ° C., rear 1
60 ° C., injection pressure: 800 kg / cm, mold temperature: mold 60 ° C., core 60 ° C.), and a square hole-shaped concave portion (width 3 mm, height 1 mm, depth) of the fitting portion of the gear flange. 3 mm) are provided at four points in the direction perpendicular to the center of the gear flange, and the width of the tip is 3 mm, the angle is 30 °, and
The abutting tool 23 made of the material SKD30 is used for the inflow amount 1.
The drum was abutted against the drum cylinder at 5 mm, and the end of the drum cylinder was cut and bent along the shape of the concave portion to produce a photosensitive drum in which the gear flange and the drum cylinder were combined.

In order to examine the deformation around the flange connection portion of the photosensitive drum thus obtained, the roundness and the cylindricity were measured at intervals of 1 mm at a position of about 50 mm from the end of the cylinder. The measurement was performed using a machine (manufactured by Mitutoyo, RA-600). As a result, the cylindricity was 45 μm, and the deformation area was 9 mm.

The photosensitive drum thus obtained is mounted on a process cartridge of a laser beam printer manufactured by Canon Inc., and this process cartridge is placed in a high-temperature and high-humidity layer (specifically, a temperature of 32.5 ° C. and a relative humidity of 85%). At 48
After standing for a while, the process cartridge was set in the laser beam printer main body in the same environment, and 10,000 images were intermittently displayed. After image output, the photosensitive drum was removed from the process cartridge, and the joint between the gear flange and the drum cylinder was checked for any effects such as looseness, looseness, and separation due to durability. However, pitch unevenness occurred on the image due to the rotation cycle of the photosensitive drum, resulting in an image having severe density unevenness.

Further, the photosensitive drum after the endurance was fixed, and the breaking torque strength of the gear flange was measured with a commercially available torque gauge. As a result, it was 147 kg-cm.

(Comparative Example 2) An undercoat layer was formed on an aluminum cylinder made of a normal aluminum drawing cylinder (product name: H63S, 62 mm, wall thickness: 1.5 mm, length: 365.5 mm) in the same manner as in Example 1. A charge generation layer and a charge transport layer were formed, and a drum cylinder having a photosensitive layer was produced.

A polyacetal resin (trade name: “Duracon M”) was added to the drum cylinder having the photosensitive layer thus manufactured.
Drum gear made by injection molding of 90-02 “Polyplastic Co., Ltd.” is injected through an instant adhesive (trade name: “Aron Alpha 432FTW”, Toa Gosei Chemical Industry Co., Ltd., adhesive amount 0.08 g). The adhesive was bonded and left in an environment of a temperature of 32.5 ° C. and a relative humidity of 85% for 48 hours to completely cure the instant adhesive. The obtained photosensitive drum was measured in the same manner as in Example 1, and as a result, the cylindrical portion at the end of the drum was 9 μm.

After that, when the durability image evaluation was performed,
The gear flange came off when about 500 pieces were durable. Observation of the bond failure portion at this time revealed that the bond failure occurred at the interface between the gear flange and the adhesive.

The breaking torque strength at this time was 75 kg.
−cm.

(Comparative Example 3) Normal aluminum drawing cylinder (product name: H63S, outer diameter: 62 mm, wall thickness: 1.5 m)
m, length: 365.5 mm), an undercoat layer, a charge generation layer, and a charge transport layer were formed on an aluminum cylinder having the same structure as in Example 1 to produce a drum cylinder having a photosensitive layer.

Next, a drum gear was prepared by injection molding of a polyacetal resin (trade name: "Duracon M90-02", a copolymer manufactured by Polyplastics Co., Ltd.). At this time, the outer diameter of the fitting portion was φ59.06 mm. A gear flange was pressed into the drum cylinder to produce a photosensitive drum.

The obtained photosensitive drum was measured in the same manner as in Example 1, and as a result, the cylindricity of the drum cylinder end was 3
7 μm, and the deformation area was 18 mm. This is because the cylindricity deteriorated because the vicinity of the end portion was greatly expanded by press fitting.

Thereafter, the durability evaluation was similarly performed, and as a result, slight slight density unevenness in the rotation period of the photosensitive drum occurred on the image. Furthermore, after image output, the photosensitive drum was removed from the process cartridge, and the joint between the gear flange and drum cylinder was checked for any effects such as backlash or separation due to durability. Did not. However, there was some looseness between the gear flange and the drum cylinder.

Further, the photosensitive drum after the endurance was fixed, and the breaking torque strength of the flange was measured with a commercially available torque gauge. As a result, it was 93 kg-cm.

Table 1 summarizes the results of the above Examples and Comparative Examples.

* Explanation of symbols in Table 1 ：: Very good 良好: Good △: Some defects but no practical problems ×: Practical problems

[0129]

As described above, the cylindrical member according to the present invention has the following effects. (1) A cylindrical member having an end engaging member at at least one end of a cylinder, and the cylindrical end is bent and cut into a concave portion of an insertion portion of the end engaging member into the cylindrical end. In the cylindrical member, the deformation near the cylindrical portion is eliminated by suppressing the deformation force swelling outward generated at the time of bending by bending while cutting the vicinity of the cylindrical end while maintaining the pressure in the vicinity of the cylindrical end. Can be provided. (2) Since it has a highly accurate cylindricity up to the vicinity of the cylindrical end,
Since it does not affect the behavior of the spacer roller,
An extremely high-precision image without image defects such as pitch unevenness can be provided. (3) Unlike the conventional bonding method, it does not require a complete curing time of the adhesive and can be bonded in a short time, which is advantageous in productivity and cost. (4) Since no adhesive is used, there is no need for quality control, a drying step after bonding, a storage space, and the like, which is excellent in terms of management and economy. (5) Since the coupling torque strength does not depend on the material of the end engaging member, the material can be freely selected depending on the purpose and application.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a photosensitive drum showing an embodiment of the present invention.

FIG. 2 shows a cylindrical end of the bending step of the present invention;
(A) is a horizontal sectional view, (b) is a longitudinal sectional view.

FIG. 3 is a perspective view of a cylindrical end of the bending step of the present invention.

4A is a plan view and FIG. 4B is a longitudinal sectional view of a pressing member according to the present invention.

FIG. 5 (a) is a longitudinal sectional view showing a conventional bending and cutting connection process. (B) is a longitudinal sectional view showing the step of cutting and bending while holding under pressure according to the present invention.

FIG. 6 is a longitudinal sectional view showing a schematic configuration of a general transfer type electrophotographic apparatus using a photosensitive drum according to the present invention.

7 is an external perspective view of the apparatus shown in FIG.

FIG. 8 is a longitudinal sectional view of the process cartridge.

9 is an external perspective view of the process cartridge shown in FIG. 8 as viewed from the upper right side.

FIG. 10 is a right side view of the process cartridge shown in FIG.

FIG. 11 is a left side view of the process cartridge shown in FIG.

12 is an external perspective view of the process cartridge shown in FIG. 9 as viewed from the upper left side.

13 is an external perspective view showing the lower left side of the process cartridge shown in FIG. 9;

FIG. 14 is an external perspective view of a process cartridge mounting portion of the apparatus main body.

FIG. 15 is an external perspective view of a mounting portion of a process cartridge of the apparatus main body.

FIG. 16 is a longitudinal sectional view of a photosensitive drum and a driving device thereof.

FIG. 17 is a perspective view of a cleaning unit.

FIG. 18 is a perspective view of a developing unit.

[Explanation of symbols]

A: Image forming apparatus (laser beam printer) B: Process cartridge C: Cleaning unit D: Developing unit L: Deformation area X1, X2: Rotation center t: Pressing allowance 1: Optical system 1a: Laser diode 1b: Polygon mirror 1c ... Lens 1d ... Reflection mirror 1e ... Exposure opening 2 ... Recording medium 3 ... Conveying means 3a ... Paper feeding cassette 3b ... Pickup roller 3c, 3d ... Transport roller pair 3e ... Registration roller pair 3f ... Transport guides 3g, 3h, 3i ... Discharge roller 3i Reverse path 3k Flapper 3m Discharge roller pair 4 Transfer roller 5 Fixing means 5a Heater 5b Fixing roller 5c
... Driving roller 6 ... Discharge tray 7 ... Photoconductor drum 7a ... Drum shaft 7a2 ... Expanded diameter section
7b: photosensitive layer 7d: drum cylinder 7e: end face 7f: bent section 8: charging roller 9aR1: mounting flange 9aR2: small screw 9aR,
9aL: Cylindrical guide 9bR, 9bL: Detent guide 9c: Positioning pin 9d: Machine screw 9i: Upper surface 9
j ... Regulation contact part 9k1 ... Hole 9L ... Left guide member
9p right end 9q left end 9R right guide member 9v developing roller bearing box 10 developing means 10A toner container 10b toner feeding member 10d developing roller 10e developing blade 10f toner stirring member 10h antenna rod 10
i: Spacer roller 11: Cleaning means 11a: Cleaning blade 11c: Waste toner reservoir 12a, 12a1: Toner frame 12b: Developing frame 12c: Cleaning frame 12c5: Mounting hole 12n: Transfer opening 13: Device body 14: Opening / closing cover 14a: Shaft 15, 15L, 15R ... guide members 15a, 15c ...
Guide portions 15b, 15d: U groove 16: Gear flange 16a: Helical gear 16b: Fitting portion 16d: Caulking flank 16e: Side surface 16f ...
Caulking receiving surface 16g concave portion 17 coupling convex shaft 17a convex portion 18 coupling concave shaft 18a concave portion 19 arm portion 19a rotating hole 20 small gear 21 concave portion 22 coupling member 22a compression coil spring Reference numeral 23: abutment tool 23a: contact surface 23b: tool tip 23c: bending action portion 23d: tool handle portion 24: bearing 24a: boss 25: drum flange 25b: spur gear 26: fixed member 29: flange 30: pressurizing Member 30a: entrance 30b: holding layer 34: large gear 41: developing holder 47: recess 47a: rib 48: drum shutter member

Claims (12)

[Claims] 1. A cylinder comprising: a cylinder; and an engagement member fitted and attached to an inner periphery of one end in a longitudinal direction of the cylinder, and provided with a concave portion facing an inner periphery of an end of the cylinder. When bending the end of the cylinder in the cylindrical member to which the end is bent toward the recess of the engagement member and the engagement member is attached,
A cylindrical member characterized in that the cylinder end is bent while the periphery of the cylinder end to be bent is held under pressure from the outer periphery of the cylinder. 2. The cylindrical member according to claim 1, wherein the cylinder is made of a plastic metal material. 3. The cylindrical member according to claim 1, wherein the engagement member is formed of a synthetic resin molded product. 4. A process detachable from an apparatus body of an electrophotographic image forming apparatus for forming an image on a recording medium, comprising: an electrophotographic photosensitive drum; and process means acting on the electrophotographic photosensitive drum. An electrophotographic photosensitive drum used in a cartridge, comprising: a cylinder having a photosensitive layer on a surface; a cylinder fitted to and attached to an inner periphery of one end in a longitudinal direction of the cylinder, and a concave portion opposed to an inner periphery of an end of the cylinder. A drum flange provided with a drum flange, wherein the end of the cylinder is bent toward the recess of the drum flange, and the end of the cylinder is cut off in the electrophotographic photosensitive drum to which the drum flange is attached. An electrophotographic photosensitive drum, wherein the cylindrical end is bent while the periphery of the cylindrical end to be bent is held under pressure from the outer periphery of the cylinder. 5. The electrophotographic photosensitive drum according to claim 4, wherein the material of the cylinder is aluminum, aluminum alloy, iron, ferro-alloy, copper alloy. 6. The electronic device according to claim 4, wherein the drum flange is an integrally formed product, and the material of the drum flange is polyacetal, polycarbonate containing polytetrafluoroethylene, polyamide, or polyethylene. Photosensitive drum. 7. A process cartridge detachable from an apparatus main body of an electrophotographic image forming apparatus, comprising: a. A cylinder having a photosensitive layer on the surface of the cylinder and a drum flange fitted and attached to the inner periphery of one end in the longitudinal direction of the cylinder and provided with a concave portion facing the inner periphery of the end of the cylinder; An electrophotographic photosensitive drum having an end bent toward the recess of the drum flange and having the drum flange attached thereto; b. A process unit that acts on the electrophotographic photosensitive drum. 8. The process cartridge according to claim 7, wherein the material of the cylinder is aluminum, aluminum alloy, iron, ferro-alloy, or copper alloy. 9. The drum flange according to claim 7, wherein the drum flange is an integrally formed product, and a material of the drum flange is polyacetal, polycarbonate containing polytetrafluoroethylene, polyamide, or polyethylene. Process cartridge. 10. The process cartridge according to claim 7, wherein a charging unit, a developing unit or a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge, and the cartridge is detachably mountable to an image forming apparatus main body. 9. The process cartridge according to any one of items 9 to 9. 11. The process cartridge according to claim 7, wherein at least one of a charging unit, a developing unit, and a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge and can be attached to and detached from an image forming apparatus main body. 9. The process cartridge according to any one of items 9 to 9. 12. The process cartridge according to claim 7, wherein the process cartridge is configured such that at least a developing unit and an electrophotographic photosensitive member are integrally formed as a cartridge and can be attached to and detached from an apparatus main body.