JPH09197745A - Image forming device and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably attach a supporting shaft for a photoreceptor drum and to obtain a uniform image without density unevenness, even if a cartridge is disassembled and assembled several times for recycling, etc. SOLUTION: A screw groove 11a is provided in one end part of the supporting shaft 11 supporting the photoreceptor drum 1, a helical projection 7b is provided inside the holding part 7a of a cleaning container 7 bearing the supporting shaft and the supporting shaft 11 can be attached to the holding part 7a by the combination of these groove 11a and projection 7b. The attached rotational direction of the supporting shaft 11 is the same as the rotational driving direction of the photoreceptor drum 1. Even if the rotational force of the photoreceptor drum 1 is applied, the supporting shaft 11 is prevented from rotating and coming off and deflection of rotation can be prevented as well because the supporting shaft 11 is in a direction where it is screwed into the holding part 7a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as a laser printer or a copying machine, and a process cartridge attachable to and detachable from the image forming apparatus.

Here, the electrophotographic image forming apparatus forms an image on a recording medium by using an electrophotographic image forming process. For example, an electrophotographic copying machine, an electrophotographic printer (eg, LED printer, laser beam printer, etc.). , An electrophotographic facsimile machine, an electrophotographic word processor, and the like.

As the process cartridge, a charging means, a developing means or a cleaning means and an electrophotographic photosensitive member are integrally made into a cartridge, and the cartridge can be attached to and detached from the main body of the electrophotographic image forming apparatus. Also, at least one of the charging means, the developing means, and the cleaning means and the electrophotographic photosensitive member are integrally made into a cartridge which can be attached to and detached from the main body of the electrophotographic image forming apparatus. Furthermore, it means that at least the developing means and the electrophotographic photosensitive member are integrally made into a cartridge and can be attached to and detached from the main body of the electrophotographic image forming apparatus (hereinafter referred to as the image forming apparatus main body).

In the present specification, the longitudinal direction means a direction perpendicular to the conveying direction of the recording medium, and is mainly used for the process cartridge.

[0005]

The present invention is a further development of the prior art described below.

The first object of the present invention according to the present application is to secure the holding of the supporting member of the image carrier even if a rotational force is applied,
Further, it is an object of the present invention to provide an image forming apparatus which has a good rotation accuracy of an image carrier and which can stably attach a supporting member of the image carrier even after disassembling and assembling such as recycling. .

A second object of the present invention is to secure the holding of the supporting member even if the rotational force of the image carrier is applied,
Moreover, it is an object of the present invention to provide an image forming apparatus in which the image carrier has good rotation accuracy and which can stably supply a good image.

A third object of the present invention is to secure the holding of the support member even when the rotational force of the image carrier is applied,
Moreover, it is an object of the present invention to provide an image forming apparatus in which the image carrier has good rotation accuracy, can stably supply a good image, and can be easily manufactured.

A fourth object of the present invention is to secure the holding of the supporting member even if the rotational force of the image carrier is applied,
Another object of the present invention is to provide a process cartridge in which the image carrier has good rotation accuracy and can stably supply a good image.

[0010]

Means for Solving the Problems A first invention of the present invention is:
An image forming apparatus for recording an image on a recording medium, comprising: an image bearing member; and a process means acting on the image bearing member,
A spiral groove is provided at one end of a supporting member that supports the image carrier, a spiral protrusion is provided inside the holding portion that holds the supporting member, and one end having the spiral groove of the supporting member,
The holding portion of the support member provided with the spiral protrusion on the inner side allows the image carrier to be attached to the image forming apparatus main body by combining the spiral groove and the protrusion. In the image forming apparatus, the rotation direction when the support member is attached to the holding portion is the same as the rotation direction of the image carrier.

A second aspect of the present invention is an image forming apparatus for recording an image on a recording medium, which comprises an image carrier and a process means acting on the image carrier, and a support for supporting the image carrier. One end of the member and the shape of the peripheral surface of the cross section perpendicular to the longitudinal direction of the holding portion that holds the support member are uneven in the circumferential direction, and the support member and the holding portion of the support member are uneven. It becomes possible to assemble the image carrier to the image forming apparatus by combining the peripheral surfaces of, and in the above-mentioned one uneven shape, the point of the minimum diameter upstream from the point of the maximum diameter in the rotation direction of the image carrier. And a distance b from the point of the maximum diameter to the point of the minimum diameter on the downstream side next to the point of the minimum diameter are a> b. is there.

A third aspect of the present invention is an image forming apparatus for recording an image on a recording medium, the image forming apparatus having an image carrier and process means acting on the image carrier, and supporting the image carrier. The image forming apparatus is characterized in that one end of the member is formed in a screw shape, and the supporting member is incorporated by cutting an inner surface of a holding portion that holds the supporting member.

According to a fourth aspect of the present invention, in a process cartridge attachable to and detachable from an image forming apparatus main body, an image carrier, process means acting on the image carrier, and a cartridge frame for holding the image carrier and the process means. Has a body and
A spiral groove is provided at one end of a supporting member that supports the image carrier, a spiral protrusion is provided at a hole of a cartridge frame into which the supporting member is fitted, and one end of the supporting member having the spiral groove is provided. And the cartridge frame body having the spiral protrusion in the hole, the image carrier can be attached to the cartridge frame body by combining the spiral groove and the protrusion. In the process cartridge, the rotation direction when the member is attached to the cartridge frame is the same as the rotation direction of the image carrier.

According to a fifth aspect of the present invention, in a process cartridge detachable from an image forming apparatus main body, an image carrier, process means acting on the image carrier, and an image carrier and a cartridge frame holding the process means. Has a body and
One end of the supporting member that supports the image carrier and the peripheral surface of the cartridge frame that holds the supporting member in a cross section perpendicular to the longitudinal direction are uneven in the circumferential direction. The image bearing member can be assembled to the process cartridge by combining the circumferential surfaces of the unevenness, and in the above-mentioned one uneven shape, the most upstream side from the point of the maximum diameter with respect to the rotation direction of the image bearing member. A process characterized in that the relationship between a distance a to a small diameter point and a distance b to a minimum diameter point located on the downstream side next to the minimum diameter point from the maximum diameter point is a> b. It is a cartridge.

According to a sixth aspect of the present invention, in a process cartridge attachable to and detachable from an image forming apparatus main body, an image carrier, process means acting on the image carrier, and a cartridge frame body holding the image carrier and the process means. The process cartridge is characterized in that one end of a support member for supporting the image carrier is formed into a screw shape, and the support member is incorporated by cutting a hole of the cartridge frame.

In a seventh aspect of the present invention, the process cartridge comprises a charging means, a developing means or a cleaning means and an electrophotographic photosensitive member which are integrally formed into a cartridge.
The process cartridge according to the fourth, fifth, or sixth invention, wherein the cartridge is detachable from the image forming apparatus main body.

According to an eighth aspect of the present invention, the process cartridge is a cartridge in which at least one of a charging means, a developing means, and a cleaning means and an electrophotographic photosensitive member are integrally made into a cartridge and attached to and detached from the main body of the image forming apparatus. The process cartridge according to the fourth, fifth, or sixth invention that enables the process cartridge.

In a ninth aspect of the present invention, the process cartridge is the fourth or fifth or the fourth aspect in which at least the developing means and the electrophotographic photosensitive member are integrally formed into a cartridge and detachable from the main body of the image forming apparatus. 6 is the process cartridge according to the invention.

[0019]

2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus using an electrophotographic image forming process, a cartridge is integrally formed with an electrophotographic photosensitive member and process means acting on the electrophotographic photosensitive member, and the cartridge is used for image forming. A process cartridge system that can be attached to and detached from the forming apparatus main body is employed. According to this process cartridge system, the maintenance of the apparatus can be performed by the user himself without relying on a serviceman, so that the operability can be remarkably improved. Therefore, this process cartridge system is widely used in image forming apparatuses.

Such an electrophotographic photosensitive member is used as a drum-shaped image bearing member. The image carrier is rotatably supported by a drum gear attached to both sides of the drum-shaped image carrier or a fixed shaft fitted in the center of the flange, and the fixed shaft is a frame of the image forming apparatus or a process cartridge. It is fitted in the frame.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION In the embodiment of the present invention, a portion for holding a support shaft for supporting a photosensitive drum on a frame is non-rotating due to its shape. Hereinafter, a detailed description will be given with reference to the drawings.

The image forming apparatus and the process cartridge will be described before explaining the main part of the present invention.

The essential parts of the image forming apparatus are shown in FIGS.

In FIG. 2, a photosensitive drum 1 as an image bearing member is provided with a photosensitive layer on the outer circumference of a hollow cylindrical aluminum cylinder 1a, and a driving force from a driving source of the image forming apparatus main body is provided at both ends of the cylinder 1a. A receiving drum gear 14 and a gear flange 15 for driving the transfer roller 9 are fitted and fixed, and are rotatably supported by a supporting shaft (described later) that penetrates the drum gear and the center hole of the flange.

At the time of image formation, the photosensitive drum 1 is indicated by an arrow R in FIG.
It rotates in one direction, is uniformly charged by the charging roller 2, and receives a laser beam 12 for sending an image to form an electrostatic latent image. Next, the electrostatic latent image provided with toner from the non-magnetic developing sleeve 3 as a developer carrying member formed of an aluminum or stainless steel pipe becomes a toner image. More specifically, the developing sleeve 3 includes a developing container 8 containing a magnetic toner 5 as a one-component developer of the developing device.
Inside the developing sleeve 3, a plurality of magnetic poles N and S are alternately formed and fixed in the developing sleeve 3 so as to be rotatable in parallel with the photosensitive drum 1 at an opening portion facing the photosensitive drum 1. The magnet 31 is installed immovably with respect to the rotation of the developing sleeve 3. Due to the magnetic action of the magnet 31, the toner 5 in the developing container 8 is carried on the surface of the developing sleeve 3 rotating in the arrow R2 direction.

At the position of the developing container 8 on the developing sleeve 3, an elastic blade 4 as a developer regulating member is attached. The elastic blade 4 hangs above the developing sleeve 3 from above, and the abdomen portion of the free end portion of the developing sleeve 3 which extends in the direction opposite to the rotation direction indicated by the arrow R2 is the developing sleeve 3.
Abut on top. The toner 5 carried on the developing sleeve 3 is regulated in its layer thickness while passing through a portion where the elastic blade 4 contacts, so that a thin toner layer is formed on the developing sleeve 3.

The toner layer on the developing sleeve 3 is conveyed to the developing portion facing the photosensitive drum 1 by the rotation of the developing sleeve 3, and toner 5 is applied to the electrostatic latent image formed on the photosensitive drum 1 there. Are supplied and attached, whereby the latent image is developed and visualized as a toner image.

The obtained toner image is transferred by the transfer roller 9 onto the transfer material 10 sent from the paper feeding unit (not shown) by the conveying member.

The transfer roller 9 has a gear (not shown) fixed to the end portion of the transfer roller 9 meshes with a gear of a gear flange 15 coaxial with the photosensitive drum 1. The transfer material 10 on which the toner image is transferred by the transfer roller 9 is conveyed to a fixing device (not shown), where the toner image is fixed on the transfer material 10 by heat and pressure to form a permanent image, and then the image forming apparatus is operated. It is discharged outside.

On the other hand, the toner left on the surface of the photosensitive drum 1 without being transferred is cleaned and removed by the cleaning blade 6a of the cleaning device 6, and is accumulated in the cleaning container 7. After that, it is charged again by the charging roller 2, and the above image forming process is repeated.

In order to facilitate maintenance of the image forming apparatus, the developing device is the developing process unit 102,
Photosensitive drum 1, charging roller 2, and cleaning device 6
Are integrated into a process cartridge 101, and the developing process unit 102 and the process cartridge 101 are installed in the image forming apparatus main body as a detachable structure. The aspect of the process cartridge 101 is as described above.

By the way, since the photosensitive drum 1 is incorporated in the cleaning container 7, it is supported by a metal shaft such as stainless steel SUS described later. The drum gear 14 and the gear flange 15 at both ends of the photosensitive drum 1 are often supported by one or two supporting shafts 11. In the case of two supporting shafts, in addition to metals, tough plastics such as polyacetal and polycarbonate are used. Sometimes used. One support shaft 11
When the photosensitive drum 1 is supported by, there is an advantage that the shaft is less shaken and pitch unevenness due to the drive gear of the photosensitive drum 1 is not noticeable.

[Detailed Description of Embodiments] (Embodiment A) In this embodiment, as shown in FIG. 1, the photosensitive drum 1 is a cleaning member which is a frame of the process cartridge 101 by one supporting shaft 11. It is incorporated in the container 7. The support shaft 11 is made of stainless steel. Helical thread groove 11 at the end of support shaft 11 having the same diameter over the entire length
It is on the left side of the figure that a is provided and the spiral screw protrusion 7b is provided inside the bearing portion 7a of the cleaning container 7 having the center hole of the same diameter as the support shaft 11 that receives the support shaft 11. Here, the screw groove 11a of the support shaft 11 is a curve including the screw bottom and the flank as shown in FIG. 3, and in this example, it is an arc and the screw thread crest surface is flat, and the envelope circle connecting the screw threads is It is equal to the diameter d of the support shaft 11. The screw protrusion 7b of the bearing portion 7a has an arcuate cross section in contact with the screw groove 11a of the support shaft 11, and the root of the screw has a cylindrical surface.
It coincides with the top surface of the No. 1 screw thread. Therefore, by fitting the thread crest surface equal to the diameter d of the support shaft 11 made of steel material and the valley bottom between the screw projections 7b of the bearing portion 7a,
It is easy to make the center of the bearing 7a and the center of the support shaft 11 exactly coincide with each other. The support shaft 11 having the thread groove 11a is inserted from the bearing hole 7d of the bearing portion 7c on the right side in FIG. It is inserted through the aluminum cylinder 1a of the base body, fitted into the center hole 14a of the drum gear 14, and then the thread groove 11a is screwed into the projection 7b of the bearing portion 7a.

FIG. 3 shows a cross section of a contact portion between the support shaft 11 of FIG. 1 and the bearing of the cleaning container 7. In addition, the support shaft 1 is attached to the bearing portion 7c on the side opposite to the bearing portion 7a.
The cylindrical end portion on the side opposite to the side having one thread groove 11a is closely fitted.

In FIG. 1, the photosensitive drum 1 rotates in a direction in which the peripheral surface seen from the front of the drawing moves from top to bottom (R1 direction). Helical thread groove 11 at the left end of the support shaft 11
The rotation direction at the time of assembling a is also the same direction, and is left-handed.
The rotation direction of the spiral thread groove 11a means the direction (tightening direction) in which the support shaft 11 is attached to the bearing 7a of the cleaning container 7 by rotating the support shaft 11 in that direction during assembly. (The same applies hereinafter).

In this way, by making the rotation direction of the spiral screw groove 11a of the support shaft 11 the same as the rotation direction of the photosensitive drum 1 (arrow R1), the support shaft 11 rotates the photosensitive drum 1. Drum gear 14 attached to photosensitive drum 1 by force
Even when the support shaft 11 is rubbed against the center hole 14a of the gear flange 15 and the center hole 15a of the gear flange 15 and a force is applied to rotate the support shaft 11 in the same direction, the spiral screw groove 11a is formed on the screw protrusion 7b of the bearing portion 7a. Since the support shaft 11 rotates in the tightening direction by engaging, the support shaft 11 does not rotate,
In addition, it does not happen that it will come out. Further, since the support shaft 11 does not rotate, the bearing portion 7a of the cleaning container 7,
The wear of 7c is also eliminated, and the shake of the support shaft 11 can be suppressed.

Further, in the embodiment B, even if the image forming apparatus of the present configuration is disassembled and assembled by recycling a plurality of times, the bearing portion 7 of the cleaning container 7 is used.
Since the a and 7c are not worn, the support shaft 11 is always stably attached as in the case of a new product, and there is an advantage that the rotational shake does not occur.

Specifically, the bearing 7a of the cleaning container 7 has a total length of 7 mm, the interval (pitch) between the spiral screw protrusions 7b is about 1 mm, and the number of windings (number of peaks) is 3 rotations. The outer diameter of the support shaft 11 and the maximum diameter d of the spiral thread groove 11a are 6 mm, and the minimum diameter (valley diameter) is 5 mm. Therefore, the bearing portions 7a and 7c of the cleaning container 7
As for the hole diameter, the bearing hole 7d on the press-fitting side is 6 mm, and the inner diameter on the side where the spiral screw protrusion 7b is provided is 5 mm.

In the image forming apparatus having the above structure, 50
The image was evaluated by passing through many sheets, but the support shaft 11 did not come off from the bearing, and no pitch unevenness due to rotational shake was observed.

Further, 15,000 sheets were passed, the cleaning container 7 of this image forming apparatus was recycled, and 15,000 sheets were passed, but there was no problem with the image. This was repeated 3 times, but the image was the same as that of a new product, and the unevenness in pitch and the like were hardly seen, which was good.
At this time, the states of the bearings 7a and 7c of the cleaning container 7 were observed, but they were scarcely worn.

With the above-described structure, the rotation of the support shaft 11 is suppressed, the support shaft 11 is prevented from coming off the bearing, the shake of the support shaft 11 due to the wear of the bearing is suppressed, and the pitch unevenness,
It is possible to prevent uneven density and the like. In addition, even if the cleaning container 7 is recycled and reused,
Since the bearing inside of the cleaning container 7 is not worn, the supporting shaft 11 is stable even in a recycled image forming apparatus, and the rotation of the photosensitive drum 1 does not occur. It is possible.

(Embodiment B) In this embodiment B, as shown in FIG. 4, the metal shaft as the support shaft 11 is two support shafts 11A and 11B, and both ends of the cleaning container 7 in the longitudinal direction are compared. It has a built-in configuration. Therefore,
Each of the two support shafts 11 is provided with a spiral screw groove 11a, and the cleaning container 7 is provided with a spiral screw protrusion 7b on the bearing portions 7a on both sides of the photosensitive drum 1.

By using the two-shaft type in which the support shaft 11 is inserted from both ends, the amount of material can be reduced and the cost can be reduced as compared with the case of one support shaft.

As shown in FIG. 5, which shows a part of FIG. 4, the support shaft 11A includes a head portion 11e, a thread groove portion 11f, and a support portion 11.
It has a cylindrical three-step difference in which the diameter is successively reduced with g. A spiral thread groove 11a is provided in the second-step thread groove portion 11f. The rotation direction at the time of screwing the spiral thread groove 11a is the same as the rotation direction (arrow R1) of the photosensitive drum 1,
In FIGS. 4 and 5, the rotation direction of the photosensitive drum 1 (arrow R1) is the moving direction of the peripheral surface of the photosensitive drum 1 on the front side of the drawing from the top to the bottom, so the left support shaft 11A is right-handed. The right side support shaft 11B is left-handed.

With such a structure, 500,000 sheets were passed in the same manner as in Embodiment A to perform image evaluation, but no pitch unevenness due to rotational blur was observed.

Further, about 10,000 sheets are passed through the photosensitive drum 1,
The process of removing the support shaft 11 of the photosensitive drum 1 mounted in the cleaning container 7 and replacing the photosensitive drum 1 with a new photosensitive drum 1 and passing 10,000 sheets was repeated three times, but the inside of the bearing of the cleaning container 7 was worn. Even after recycling, there was almost no pitch unevenness due to blurring of the photosensitive drum 1 even after recycling, and a high quality image equivalent to that of a new image forming apparatus was obtained.

Further, FIG. 6 shows that the support shaft 11 provided with the spiral groove of the present invention is provided only on one side of the photosensitive drum 1, and the other side (right side in the figure) is integrated with the gear flange 15 of the photosensitive drum 1. This is the case where the support shaft 11C is used. In this case, the support shaft 11C serves as a rotation shaft, and the bearing surface 7c1 of the bearing portion 7c.
Is supported by.

The above structure has an advantage that the cost is about half that of the case where two support shafts 11 are used, because the support shaft 11 with the spiral thread groove 11a is provided only on one side.
Although the support shaft 11 with the spiral thread groove 11a is provided on only one side, wear of the bearing portion 7a of the support shaft 11 on the drum gear 14 side to which a larger tooth load is applied can be suppressed, so that the effect of the present invention is sufficient. It was confirmed that it can be achieved.

As described above, from the both ends of the photosensitive drum 1, 2
Also in a configuration in which the photosensitive drum 1 is supported by one screw shaft supporting shaft 11 or one screw shaft supporting shaft 11 on one side, a spiral screw groove 11 a is provided in a part of the supporting shaft 11 to form the photosensitive drum 1. By setting the direction of the screw groove 11a so that the rotation is in the same direction as the direction of rotation so that the screw groove 11a is self-locking, the photosensitive drum 1
The wear of the bearing portion of the support shaft 11 due to the rotation can be suppressed, and the blur can be suppressed to the minimum, and a uniform image without unevenness can be obtained. Further, the inner wear of the bearing of the cleaning container 7 can be reduced, and even if the cleaning container 7 is recycled, the support shaft 11 is prevented from blurring and the images are not affected.

(Embodiment C) In this embodiment C, the support shaft 11 and the bearing surface of the bearing portion 7a are fitted with each other in a modified cross section.

FIG. 7 is a perspective view of the support shaft 11 of this embodiment and the bearing portion 7a of the cleaning container 7 that receives it.
FIG. 8 shows a sectional view perpendicular to the axis when the support shaft 11 is incorporated in the cleaning container 7.

In the present embodiment C, one end of the support shaft 11 for supporting the photosensitive drum 1 and the cross-sectional shape of the bearing surface of the cleaning container 7 at right angles to the axis are curved irregularities in the circumferential direction as shown in FIG. The support shaft 11 is assembled to the bearing portion 7 a of the cleaning container 7 by combining the uneven shapes. In this one concavo-convex shape, the distance a from the point of the maximum diameter (point B) to the point of the minimum diameter on the upstream side (point A) in the driving rotation direction of the photosensitive drum 1 (arrow R1), The relation with the distance b from the point of maximum diameter (point B) to the point of minimum diameter (point C) on the downstream side of point A adjacent to point A is a> b.

The bearing surface 7a1 connecting the points A and B is a curve that is convex outward when viewed from the center O of the support shaft 11 and the bearing portion 7a. Further, the bearing surface 7a2 connecting the points B and C is a convex curve toward the bearing surface 7a1. These curves are circles and other quadratic curves. The end of the support shaft 11 has the same shape as the bearing surfaces 7a1 and 7a2 fitted with a margin. The points C and B are the center O
On the same straight line L in the radial direction.

The force received by the support shaft 11 by the driving rotational force of the photosensitive drum 1 is perpendicular to the radial line L passing through the center O and the point B of the support shaft 11 as viewed in the axial direction (P). Is. Therefore, in the case of a> b, the bearing surface 7a2 between B and C of the uneven portion has a curved shape that intersects substantially perpendicularly to the force (P), and the action of suppressing the rotation of the support shaft 11 is suppressed. do. Further, in the present embodiment C, a curve between A and B and a curve between B and C are curved, and the bearing surface 7a2 between B and C and the bearing surface 7a1 adjacent to the bearing surface 7a2 are provided.
Since the distance (X) to the intersection D (corresponding to the point B) of 7a2 can be set large, that is, the root side of the meat portion of the bearing portion 7a forming the bearing surface 7a2 is large, the force received between B and C ( It can withstand P) sufficiently. The reason why the cleaning container 7 has such a shape is that the cleaning container 7 is made of synthetic resin, and the support shaft 11 is generally iron-based metal so as to suppress deformation of the synthetic resin member due to load.

Therefore, since the support shaft 11 does not rotate even when the driving torque of the photosensitive drum 1 is applied, the bearing surfaces 7a1 and 7a2 inside the bearing portion 7a are not worn. Therefore, it is possible to prevent the support shaft 11 from coming off,
It is possible to suppress the blurring of.

Specifically, the support shaft 11 has an uneven shape up to 5 mm inward in the longitudinal direction from the end, and the minimum diameter of the concave through the point A is 5 mm, the maximum diameter of the convex through the point B is 7 mm, and a =
The concave and convex shape of the curve was 4.5 mm and b = 2 mm, and the concave and convex portions were arranged in six equal parts in the circumferential direction. The bearing side was also provided with 6 irregularities with similar dimensions.

In the structure of the present embodiment (B), about 400,000 sheets of the photosensitive drum 1 were passed, but there was almost no wear inside the bearing portion 7a of the cleaning container 7, and the pitch unevenness due to the blurring of the photosensitive drum 1 or the like occurred. A high quality image with almost no image was obtained.

As described above, the cross-sectional shape of the one end of the support shaft 11 and the bearing of the cleaning container 7 at right angles to the longitudinal direction has a curved concave and convex shape as shown in FIG. 8, and by combining the concave and convex shapes. The support shaft 11 is assembled to the bearing of the cleaning container 7, and in one concavo-convex shape, it has the smallest diameter in the driving rotation direction of the photosensitive drum (A
Distance a from the point) to the point (point B) of the maximum diameter on the downstream side,
The rotation of the photosensitive drum 1 can be achieved by setting the relationship a> b with the distance b from the point of the maximum diameter (point B) to the point of the minimum diameter adjacent to the point A on the downstream side (point C). It is possible to suppress wear of the bearing portion of the support shaft 11 due to the above, to minimize disengagement and blurring of the support shaft 11, and obtain a uniform image without unevenness. Although the bearing surfaces 7a1 and 7a2 are curved, the same effect can be obtained even if they are straight.

(Embodiment 2) In this embodiment, 1
The end of the book support shaft 11 on the insertion side is formed into a screw shape, and the inner surface of the bearing portion into which the support shaft 11 is screwed is formed into the support shaft 11.
The cylindrical surface has a diameter smaller than the outer diameter of the screw shape.

FIG. 9 shows a perspective view of the support shaft 11 of this embodiment and the bearing of the cleaning container 7 that receives the support shaft 11.

In this embodiment, when the support shaft 11 is attached to the cleaning container 7, the end screw portion 11b of the triangular support screw shaft 11 is rotated and the bearing of the support shaft 11 of the cleaning container 7 is rotated. It is inserted into the bearing surface 7a1 of the portion 7a. The inner diameter of the bearing surface 7a1 of the bearing portion 7a of the cleaning container 7 is equal to the screw portion 11b of the support shaft 11.
Is smaller than the maximum diameter of. Screw part 11 of support shaft 11
b presses the bearing surface 7a1 while cutting the tap. Therefore, since the support shaft 11 receives a considerably large pressure from the bearing surface of the bearing portion 7a of the cleaning container 7, it is firmly held and the photosensitive drum 1 is held.
Since the support shaft 11 does not rotate even when the driving torque is applied, it is possible to prevent the support shaft 11 from coming off and the rotational shake of the support shaft 11. Further, in the present embodiment D, when the cleaning container 7 is produced by a mold, it is only necessary to make the bearing surface 7a1 into a cylindrical shape having an inner diameter smaller than the outer diameter of the screw of the support shaft 11, and therefore, compared with the previous embodiment. There is also an advantage that die cutting is very easy and the cost can be reduced.

Specifically, the screw portion 1 at the end of the support shaft 11
The screw shape of 1b has an outer diameter of 8 mm, a root diameter of 6 mm, and the bearing portion 7a has an inner diameter of 7 mm and a length of 15 mm.

In this embodiment, the image was evaluated by passing about 500,000 sheets of the photosensitive drum 1.
A high-quality image having almost no pitch unevenness due to blurring of the photosensitive drum 1 was obtained without coming out of the cleaning container 7.

As described above, one end of the support shaft 11 is formed into a screw shape, and the support shaft 11 is incorporated by cutting the inner surface of the bearing portion 7a of the cleaning container 7, whereby the support shaft 11 is rotated by the rotation of the photosensitive drum 1. The wear of the bearings can be suppressed, and the detachment and blurring of the support shaft 11 can be suppressed to the minimum, and a uniform image without unevenness can be obtained.

(Embodiment E) In this embodiment, the image forming apparatus of the present invention is incorporated in a process cartridge which is detachable from the main body of the image forming apparatus.

FIG. 10 shows a vertical sectional view of the process cartridge of the present embodiment.

Process cartridge 1 of the present embodiment E
Reference numeral 01 denotes a photosensitive drum 1 as an image carrier, a charging roller 2 as a charging device, a developing container 8, and a cleaning device 6.
It consists of four process equipments. The structure of the process cartridge 101 is described at the beginning.

The developing container 8 of the process cartridge 101 of this embodiment has a developing sleeve 3 containing a fixed magnet 31, a developing container 8 containing a magnetic toner 5 as a developer, and a uniform thickness of the toner 5 on the developing sleeve 3. It has a developing elastic blade 4 for coating.

The cleaning device 6 has a cleaning blade 6a and a cleaning container 7. The photosensitive drum 1 is supported by the frame body of the cleaning device 6 by the support shaft 11 (not shown) of the embodiment B or the embodiment B.

When the process cartridge 101 is properly mounted in the main body of the image forming apparatus, the externally exposed portion surface of the photosensitive drum 1 is in pressure contact with the transfer roller 9 on the main body side of the image forming apparatus.

The process cartridge 101 and the image forming apparatus main body are mechanically and electrically coupled to each other, and the process cartridge 10 is driven by the drive mechanism of the image forming apparatus main body.
It is possible to drive the photosensitive drum 1, the developing sleeve 3, etc. on the first side, and to apply a charging bias to the charging roller 2 via the electrode contact on the process cartridge 101 side by the power source (electrical circuit) on the main body side of the image forming apparatus. It is possible to apply a developing bias to the developing sleeve 3, and the image forming operation can be executed.

An output laser beam 12 from a laser scanner (not shown) on the image forming apparatus main body side enters the process cartridge 101, and the surface of the rotating photosensitive drum 1 is scanned and exposed.

In such a process cartridge 101, the number of prints until the end of its life is small, but since the life of the image forming apparatus main body is extremely long, the number of times of replacement of the process cartridge 101 is large, and the main body of the image forming apparatus is increased. Process cartridge 101 against the number of production of
The production number of is very large. Therefore, the process cartridge 101 is recycled, and it is conceivable that the process cartridge 101 is recycled not only once but also several times.

According to the present invention, the support shaft 11 of the photosensitive drum 1 has a spiral groove, as described in Embodiments A and B.
The bearing 7a of the cleaning device 6 is a spiral protrusion, and since the support shaft 11 is in the direction of being fastened to the bearing 7a of the cleaning container 7 with respect to the rotation direction of the photosensitive drum 1, the support shaft 11 rotates and the bearing is rotated. It does not come off from the portion 7a, and the bearing portion 7 is formed by the rotation of the support shaft 11.
Since there is almost no wear inside a, the support shaft 11 does not shake even when the cleaning container 7 is reused several times. Therefore, the pitch unevenness and the density unevenness due to the blurring of the photosensitive drum 1 do not occur at all, and the image can always maintain the high image quality. Therefore, in the case of a process cartridge that is easily recycled, the effect of the present invention is very large.

It is needless to say that the same effect can be obtained when the present embodiment E includes the embodiment C and the embodiment D.

[0076]

As described above, according to the first invention of the present application, the spiral groove is provided at one end of the supporting member for supporting the image carrier, and the holding portion for holding the supporting member is provided. One end of the support member having a spiral groove provided inside and the spiral groove of the support member and the holding portion of the support member provided with the spiral projection inside of the support member are a combination of the spiral groove and the projection. The photosensitive drum can be attached to the main body of the image forming apparatus by being combined, and the rotation direction when attaching the supporting member to the holding portion by the spiral groove is the same as the rotation direction of the image carrier. Since it is a featured image forming device, it is possible to suppress wear inside the holding part, the support member is stable, and there is no rotational shake of the image carrier, so it is possible to obtain image quality as good as new. Is.

According to the second invention of the present application, the shape of the one end of the supporting member for supporting the image carrier and the peripheral surface of the cross section perpendicular to the longitudinal direction of the holding portion for holding the supporting member is the circumferential direction. The supporting member and the holding member of the time member can be assembled in the image forming apparatus by the combination of the uneven shapes, and in the one uneven shape, the image carrier is The distance a from the point of the maximum diameter to the point of the minimum diameter upstream from the point of the maximum diameter, and from the point of the maximum diameter to the point of the minimum diameter downstream of the point of the minimum diameter. Since the image forming apparatus is characterized in that the relationship with the distance b is a> b, wear inside the holding portion can be suppressed, and movement of the support member can be prevented. Therefore, the supporting member is stable, and the image carrier does not rotate, so that a high quality image can be obtained.

According to the third invention of the present application, one end of the supporting member for supporting the image carrier is formed into a screw shape, and the supporting member is incorporated by cutting the inner surface of the holding portion for holding the supporting member. Since the image forming apparatus is characterized by the above, the supporting member does not rotate even if the supporting member receives sliding friction of the driving rotation of the image carrier, and the supporting member is immovable. Therefore, since the supporting member is stable and the image carrier does not rotate, it is possible to obtain a high quality image.

The above-described configurations of the invention can obtain the same effects as described above by being applied to any one of the fourth to ninth process cartridges, and can increase the number of times of recycling, thus saving resources. .

[0080]

[Embodiments] These are described together with the embodiments.

[Brief description of drawings]

FIG. 1 is a front view of a cleaning container according to a first embodiment.

FIG. 2 is a longitudinal sectional view of a main part of the image forming apparatus according to the embodiment A.

FIG. 3 is a vertical cross-sectional view of a contact portion between the support shaft and the bearing of the cleaning container according to the embodiment A.

FIG. 4 is a front view of the cleaning container showing the embodiment B.

FIG. 5 is a vertical cross-sectional view of a contact portion between the support shaft and the bearing of the cleaning container according to the embodiment B.

FIG. 6 is a front view showing an application example of the embodiment B.

FIG. 7 is a perspective view of a support shaft and a bearing of a cleaning container showing the embodiment C.

FIG. 8 is a sectional view perpendicular to the axis of the bearing of the cleaning container showing the embodiment C.

FIG. 9 is a perspective view of the support shaft and the bearing of the cleaning container according to the second embodiment.

FIG. 10 is a vertical cross-sectional view of the process cartridge showing the embodiment E.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Photosensitive drum 1a ... Aluminum cylinder 2 ... Charging roller 3 ... Developing sleeve 4 ... Elastic blade 5 ... Magnetic toner 6 ... Cleaning device 6a ... Cleaning blade 7 ... Cleaning container 7a ... Bearing part 7a1 ... Bearing surface 7b ... Screw protrusion 7c ... Bearing portion 7c1 ... Bearing surface 7d ... Bearing hole 8 ... Developing container 9 ... Transfer roller 10 ... Transfer material 11 ... Support shaft 11A, 11B, 11C ... Support shaft 11
a ... screw groove 11b ... screw part 11e ... head part 11f ...
Screw groove portion 11g ... Support portion 12 ... Laser light 14 ... Drum gear 14a ... Center hole 15 ... Gear flange 15a ... Center hole 31 ... Fixed magnet 101 ... Process cartridge 102 ... Development process unit

Claims (9)

[Claims] 1. An image forming apparatus for recording an image on a recording medium, comprising: an image bearing member; and process means acting on the image bearing member, wherein a spiral member is provided at one end of a supporting member for supporting the image bearing member. A groove is provided, a spiral projection is provided inside the holding portion that holds the support member, and one end of the support member having the spiral groove is provided.
The holding portion of the support member provided with the spiral protrusion on the inner side allows the image carrier to be attached to the main body of the image forming apparatus by combining the spiral groove and the protrusion. An image forming apparatus, wherein a rotation direction when the support member is attached to the holding portion is the same as a rotation direction of the image carrier. 2. An image forming apparatus for recording an image on a recording medium, comprising: an image bearing member; and a process means acting on the image bearing member; one end of a supporting member for supporting the image bearing member; The shape of the peripheral surface of the holding portion that holds the member in a cross section perpendicular to the longitudinal direction is uneven in the circumferential direction, and the supporting member and the holding portion of the supporting member have a combination of uneven peripheral surfaces. It becomes possible to assemble the image carrier to the image forming apparatus, and in the above-mentioned one uneven shape, with respect to the rotation direction of the image carrier,
Distance a from the point of maximum diameter to the point of minimum diameter upstream
And the distance b from the point of the maximum diameter to the point of the minimum diameter on the downstream side next to the point of the minimum diameter is a> b. 3. An image forming apparatus for recording an image on a recording medium, comprising: an image bearing member; and process means acting on the image bearing member, wherein one end of a supporting member for supporting the image bearing member has a screw shape. hand,
An image forming apparatus, wherein the supporting member is incorporated by cutting an inner surface of a holding portion that holds the supporting member. 4. A process cartridge attachable to and detachable from a main body of an image forming apparatus, comprising: an image carrier, process means acting on the image carrier, and a cartridge frame body holding the image carrier and the process means. A spiral groove is provided at one end of a supporting member that supports the image carrier, a spiral protrusion is provided at a hole of a cartridge frame into which the supporting member is fitted, and one end of the supporting member having the spiral groove is provided. And the cartridge frame body having the spiral protrusion in the hole, the image carrier can be attached to the cartridge frame body by combining the spiral groove and the protrusion. A process cartridge characterized in that a rotation direction when the member is attached to the cartridge frame is the same as a rotation direction of the image carrier. 5. A process cartridge attachable to and detachable from a main body of an image forming apparatus, comprising: an image carrier, process means acting on the image carrier, and a cartridge frame body holding the image carrier and the process means. One end of the supporting member that supports the image carrier and the peripheral surface of the cartridge frame that holds the supporting member in a cross section perpendicular to the longitudinal direction are uneven in the circumferential direction. The image bearing member can be assembled to the process cartridge by combining the circumferential surfaces of the unevenness, and in the above-mentioned one uneven shape, the maximum diameter on the upstream side of the maximum diameter with respect to the rotation direction of the image bearing member. The process is characterized in that the relationship between the distance a to the point of the small diameter and the distance b to the point of the smallest diameter on the downstream side of the point of the smallest diameter from the point of the largest diameter is a> b. Cartridge. 6. A process cartridge attachable to and detachable from an image forming apparatus main body, comprising: an image carrier, process means acting on the image carrier, and a cartridge frame body holding the image carrier and the process means. One end of the support member that supports the image carrier is formed into a screw shape,
A process cartridge, wherein the support member is incorporated by cutting a hole of a cartridge frame. 7. The process cartridge comprises a charging means, a developing means or a cleaning means, and an electrophotographic photosensitive member which are integrally formed into a cartridge, and the cartridge can be attached to and detached from the main body of the image forming apparatus. 5
Alternatively, the process cartridge according to item 6. 8. The process cartridge, wherein at least one of a charging unit, a developing unit, and a cleaning unit and an electrophotographic photosensitive member are integrally made into a cartridge, which is attachable to and detachable from the main body of the image forming apparatus. The process cartridge according to 5 or 6. 9. The process cartridge according to claim 4, 5 or 6, wherein at least the developing means and the electrophotographic photosensitive member are integrally made into a cartridge so as to be attachable to and detachable from the main body of the image forming apparatus.