JPH1195639A - Process cartridge, driving force transmitting parts, electrophotographic photoreceptor drum, and electrophotographic image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the rotation accuracy of a photoreceptor drum by making the protruding part of a main body enter the recessed part of a cartridge when a process cartridge is attached to the device main body. SOLUTION: A coupling protruding shaft 17 (columnar shape) is provided on a drum flange fixed to one end part of the photoreceptor drum 7, and the protruding part 17a is formed on the leading end face of the shaft 17. Besides, the end face of the part 17a is in parallel with the end face of the shaft 17. The shaft 17 fits in a bearing, and functions as a drum rotary shaft. The flange, the shaft 17 and the part 17a are integrally provided, and a helical gear 16a is integrally provided on the flange in order to transmit driving force to a developing roller inside the process cartridge. When the part 17a fits in the recessed part 18a provided on the device main body, and the rotary force of the part 18a is transmitted to the part 17a; shaft centers are aligned with each other because the respective apexes of a nearly regular triangular part 17a equally abut on the inside surface of the part 18a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process cartridge, an electrophotographic image forming apparatus, a driving force transmitting component, and an electrophotographic photosensitive drum. Here, the electrophotographic image forming apparatus forms an image on a recording medium using an electrophotographic image forming method. As examples of the electrophotographic image forming apparatus, for example, an electrophotographic copying machine,
Electrophotographic printer (for example, laser beam printer, L
ED printers, etc.), facsimile machines, word processors, etc.

A process cartridge is a unit in which 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 made detachable from an image forming apparatus main body. And at least one of a charging unit, a developing unit, and a cleaning unit.
And an electrophotographic photosensitive member, which is integrally formed into a cartridge so that the cartridge can be attached to and detached from the image forming apparatus main body. Further, it refers to a device in which at least the developing means and the electrophotographic photosensitive member are integrally formed as a cartridge so as to be detachable from the apparatus main body. Here, the process cartridge can be attached to and detached from the apparatus main body by the user himself / herself, so that maintenance of the apparatus main body can be easily performed.

[0003]

2. Description of the Related Art An electrophotographic image forming apparatus using an electrophotographic image forming system forms a latent image by selectively exposing an electrophotographic photosensitive member uniformly charged by a charging means in accordance with image information. I do. Then, the latent image is developed by a developing unit using toner to form a toner image. afterwards,
The toner image formed on the electrophotographic photoreceptor is transferred to a recording medium by a transfer unit to form an image.

Here, various methods have been considered to rotationally drive the electrophotographic photosensitive drum.

One method is disclosed in Japanese Patent Application Laid-Open No. 62-65049.
As described in the publication, a pin fixed to a side surface of a gear provided on the main body is fitted into a concave portion provided on a side surface of a gear provided on the photosensitive drum to rotate the photosensitive drum. It is a way to make it.

Another method is disclosed in JP-A-63-4252.
As described in Japanese Patent Application Laid-Open Publication No. H10-209, a method is used in which a helical gear provided on a main body and a helical gear provided on a photosensitive drum are fitted to rotate the photosensitive drum.

[0007]

The techniques described in the above publications are all very effective as a structure for transmitting a rotational force to a 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 process cartridge, an electrophotographic image forming apparatus, a driving force transmitting component, and an electrophotographic photosensitive drum, which can improve the rotation accuracy of the electrophotographic photosensitive drum.

Another object of the present invention is to provide a process cartridge, an electrophotographic image forming apparatus, a driving force transmitting component, and an electrophotographic photosensitive member capable of reliably transmitting a driving force from an apparatus main body to an electrophotographic photosensitive drum. It is to provide a body drum.

Another object of the present invention is to provide a driving force transmission (at the time of image formation), a rotation center of a coupling provided on an apparatus main body and a coupling provided on an electrophotographic photosensitive drum. It is an object of the present invention to provide a process cartridge, an electrophotographic image forming apparatus, a driving force transmitting component, and an electrophotographic photosensitive drum which can substantially match the rotation center of the photosensitive drum.

Another object of the present invention is to provide a process cartridge and an electronic device which can improve the positioning accuracy of the process cartridge relative to the apparatus main body by pulling the electrophotographic photosensitive drum toward the apparatus main body when transmitting the driving force. An object of the present invention is to provide a photographic image forming apparatus, a driving force transmitting component, and an electrophotographic photosensitive drum.

Another object of the present invention is to provide a process cartridge, an electrophotographic image forming apparatus, a driving force transmitting component, and an electrophotographic photosensitive drum which can improve image quality.

Another object of the present invention is to disconnect the driving force transmission mechanism between the apparatus main body and the process cartridge when the driving force is not transmitted (during non-image formation). An object of the present invention is to provide a process cartridge, an electrophotographic image forming apparatus, a driving force transmitting component, and an electrophotographic photosensitive drum, which can improve the operability of removing the process cartridge from the apparatus main body.

Another object of the present invention is to provide a process cartridge, a driving force transmitting component, an electrophotographic photosensitive drum, which can prevent a foreign substance from entering the inside of the recess because the projection is provided inside the recess. Another object of the present invention is to provide an electrophotographic image forming apparatus.

Another object of the present invention is to provide a process cartridge which can improve the shape accuracy of a convex portion even if the convex portion is manufactured by molding by providing a hole in an end face of the convex portion. It is an object to provide a component, an electrophotographic photosensitive drum, and an electrophotographic image forming apparatus.

Another object of the present invention is to provide a process cartridge which can improve the shape accuracy of a concave portion even if the concave portion is manufactured by molding by expanding a portion of the concave portion which does not contact the convex portion outward. , A driving force transmitting component, an electrophotographic photosensitive drum, and an electrophotographic image forming apparatus.

Another object of the present invention is to form a projection inside the concave portion and a hole at the tip of the convex portion. The process cartridge, the driving force transmitting component, the electrophotographic photosensitive drum, and the electrophotographic image forming apparatus capable of preventing the concave portion and the convex portion from being damaged even if the device is transported or carried. To provide.

[0018]

A typical configuration according to the present invention for achieving the above object is a motor, an apparatus body gear for receiving a driving force transmitted from the motor, and an apparatus body gear. And a main body concave portion formed of a twisted surface, substantially provided on a coaxial line, and a main body convex portion provided inside the main body concave portion and substantially coaxially with the device main body gear, A process cartridge having an electrophotographic image forming apparatus for forming an image on a recording medium, the process cartridge being detachable from an apparatus main body of the electrophotographic image forming apparatus, the electrophotographic photosensitive drum, and a process unit acting on the electrophotographic photosensitive drum. A twisted cartridge projection provided at one end in the longitudinal direction of the electrophotographic photosensitive drum and fitted with the twisted concave portion; and a tip end of the cartridge projection, substantially the same as the cartridge projection. A cartridge recess provided on a coaxial line, and wherein the main body projection enters the cartridge recess when the process cartridge is mounted on the apparatus main body. When mounted, when the main body gear rotates in a state where the cartridge projection is fitted with the main body recess, through the main body recess and the cartridge projection,
The rotational force of the main body gear is transmitted to the electrophotographic photosensitive drum.

A typical configuration according to the present invention for achieving the above object is a motor, an apparatus main body gear for receiving a driving force transmitted from the motor, and an apparatus main body gear substantially equivalent to the apparatus main body gear. A main body recess provided on a coaxial line and configured with a twisted surface, wherein the main body recess is provided on the apparatus main body gear, at a tip of a cylindrical shaft provided coaxially with the apparatus main body gear. And the body recess is substantially triangular in cross section, and a portion of the twisted surface of the body recess that does not abut the cartridge projection has an arc substantially along the outer circumference of the shaft. An electrophotographic apparatus for forming an image on a recording medium, comprising: a concave portion having a shape surface; a convex portion provided inside the main body concave portion and substantially coaxially with the apparatus main body gear; Image forming device book An electrophotographic photosensitive drum, a process unit acting on the electrophotographic photosensitive drum, and the twisted recess provided at one longitudinal end of the electrophotographic photosensitive drum. A fitted cartridge projection, wherein the cartridge projection is substantially triangular prism-shaped, a tip of the cartridge projection, and a cartridge recess provided substantially coaxially with the cartridge projection; Here, when the process cartridge is mounted on the apparatus main body, the main body convex portion enters the cartridge concave portion, where a drum flange is provided at one end of the electrophotographic photosensitive drum, and A drum flange is provided for rotatably supporting the electrophotographic photosensitive drum on a cartridge frame. Wherein the cartridge projection and the cartridge recess are provided at the tip of the shaft. The cartridge projection is attached to the main assembly when the process cartridge is mounted on the apparatus main assembly. When the main body gear is rotated in a state of being fitted in the concave portion, a rotational force of the main body gear is transmitted to the electrophotographic photosensitive drum via the main body concave portion and the cartridge protrusion. And

A typical configuration according to the present invention for achieving the above object is a motor, a driving rotary body for receiving a driving force from the motor, and a rotation center axis of the driving rotary body. An electrophotographic image forming apparatus for forming an image on a recording medium having a coaxial twisted non-circular cross-section concave portion having an inner convex portion or a twisted non-circular cross-sectional convex portion having an inner concave portion. A process cartridge detachable from the main body, comprising: a rotatable electrophotographic photosensitive drum; process means acting on the electrophotographic photosensitive drum; and a rotation center axis at one longitudinal end of the electrophotographic photosensitive drum. A concave portion provided with a twisted non-circular cross section having an inner concave portion or a concave portion having an inner convex portion provided coaxially and capable of fitting with the non-circular concave portion or the convex portion. The convex portion of the photosensitive drum or The portion has a first rotational direction relative position rotatable relative to the drive rotating body, and a shape capable of taking a second rotational direction relative position in which the two rotational center axes are substantially coaxial and one direction cannot be relatively rotated. It has dimensions and can take the first rotational direction relative position and the second rotational direction relative position in a state where the inner convex portion of the twisted concave portion enters the inner concave portion of the twisted convex portion. And

A typical configuration according to the present invention for achieving the above object includes a motor, an apparatus main body gear for receiving a driving force transmitted from the motor, and substantially the apparatus main body gear. Provided in the center, a main body recess formed by a polygonal twisted cross-section that rotates integrally with the device main body gear, and a main body projection provided inside the main body recess, An electrophotographic photosensitive drum included in a process cartridge detachable from an apparatus main body of an electrophotographic image forming apparatus for forming an image on a recording medium, and a developing roller for developing a latent image formed on the electrophotographic photosensitive drum And a gear for transmitting a driving force to the developing roller, the driving force transmitting component for transmitting a driving force to the developing roller when the process cartridge is mounted on the apparatus main body. A shaft provided at the center of the gear and a hole for receiving a driving force from the apparatus main body when the process cartridge is mounted on the apparatus main body, the hole is fitted to the shaft provided at the apparatus main body. It has a twisted cartridge projection provided at the tip of the shaft portion, and a cartridge recess provided in the projection, and in a state where the main body projection has entered the cartridge recess, the main body recess and the cartridge projection are formed. The driving force received from the apparatus main body via the shaft portion is transmitted to the electrophotographic photosensitive drum via the shaft portion, and is transmitted to the developing roller via the helical gear.

A typical configuration according to the present invention for achieving the above object includes a motor, an apparatus body gear for receiving a driving force transmitted from the motor, and a substantial part of the apparatus body gear. A recording apparatus comprising: a main body recess provided in a central portion, a main body recess provided on the inside of the main body recess, and a main body recess formed by a polygonal twisted surface that rotates integrally with the apparatus main body gear. An electrophotographic photosensitive drum used in a process cartridge detachable from an apparatus main body of an electrophotographic image forming apparatus for forming an image on a medium, comprising: a. A cylinder having a photosensitive layer on a peripheral surface; b. A gear for transmitting a driving force received from the apparatus main body to the developing roller when the process cartridge is mounted on the apparatus main body, a shaft provided at a central portion of the gear, and a process cartridge mounted on the apparatus main body. A twisted cartridge projection provided at the tip of the shaft portion for receiving the driving force from the apparatus main body when fitted into the hole provided in the apparatus main body when mounted, and provided on the projection. And a driving force received from the apparatus main body via the main body concave portion and the cartridge protrusion in a state where the main body protrusion enters the cartridge concave portion via the shaft portion. To the body drum,
A driving force transmitting component attached to one end of the cylinder, the driving force transmitting component transmitting to the developing roller via the helical gear.

A typical configuration according to the present invention for achieving the above object is to provide an electrophotographic image forming apparatus for forming an image on a recording medium in which a process cartridge is detachable. A motor; and (b) an apparatus body gear for receiving transmission of driving force from the motor;
(C) a main body recess formed of a twisted surface and provided substantially coaxially with the device main body gear; and (d) inside the main body recess and substantially coaxial with the device main body gear. (E) an electrophotographic photosensitive drum, process means acting on the electrophotographic photosensitive drum, and the torsion provided at one longitudinal end of the electrophotographic photosensitive drum. A twisted cartridge projection that fits into the recess, a cartridge recess provided at the tip of the cartridge projection and substantially coaxial with the cartridge projection, and the process cartridge is mounted on the apparatus main body. When the process cartridge is mounted on the apparatus main body, the cartridge projections When the main body gear rotates in a state fitted in the concave portion, a process cartridge configured to transmit the rotational force of the main body gear to the electrophotographic photosensitive drum via the main body concave portion and the cartridge protrusion. Cartridge mounting means for removably mounting the cartridge.

A typical configuration according to the present invention for achieving the above object is to provide an electrophotographic image forming apparatus for forming an image on a recording medium in which a process cartridge is detachable. A motor; and (b) an apparatus body gear for receiving transmission of driving force from the motor;
(C) a body recess formed of a twisted surface substantially coaxially provided with the device body gear, wherein the body recess is provided in the device body gear and coaxially with the device body gear. Provided at the tip of a shaped cylindrical shaft, and the body recess is substantially triangular in cross section,
And, among the twisted surfaces of the main body concave portion, a portion not in contact with the cartridge projection has a concave portion having an arc-shaped surface substantially along the outer periphery of the shaft. (D) Inside the main body concave portion A process cartridge detachable from an apparatus main body of an electrophotographic image forming apparatus for forming an image on a recording medium, the process cartridge comprising: the apparatus main body gear; and a main body projection provided substantially coaxially. (E) an electrophotographic photoreceptor drum, process means acting on the electrophotographic photoreceptor drum, and a twisted engagement with the twisted recess provided at one longitudinal end of the electrophotographic photoreceptor drum. A cartridge projection, wherein the cartridge projection is a substantially triangular prism-shaped tip of the cartridge projection, the cartridge projection being substantially coaxial with the cartridge projection. A cartridge recess and, when the process cartridge is mounted on the apparatus main body, the main body protrusion enters the cartridge recess. Here, a drum flange is provided at one end of the electrophotographic photosensitive drum. And a shaft for rotatably supporting the electrophotographic photosensitive drum on a cartridge frame on the drum flange, and a cartridge projection and a cartridge recess provided at a tip of the shaft. When the process cartridge is mounted on the apparatus main body and the main body gear is rotated in a state where the cartridge protrusion is fitted into the main body concave portion, the main body concave portion and the cartridge protrusion are connected to each other. A process cartridge configured to transmit the rotational force of the main body gear to the electrophotographic photosensitive drum via And having a cartridge mounting means for detachably mounting a di-, a.

A typical configuration according to the present invention for achieving the above object is an electrophotographic image forming apparatus for forming an image on a recording medium in which a process cartridge is detachable. A motor; (b) a driving rotator for receiving a driving force from the motor; and (c) a concave portion having a twisted non-circular cross-section having an inner convex portion substantially coaxial with a rotation center axis of the driving rotator. Or (d) a rotatable electrophotographic photosensitive drum, process means acting on the electrophotographic photosensitive drum, and a longitudinal length of the electrophotographic photosensitive drum. A concave portion having a convex or inner convex portion having a twisted non-circular cross section with an internal concave portion, which is provided coaxially with the rotation center axis at one end in the direction, and can be fitted with the non-circular concave portion or convex portion Having the electrophotographic feeling The convex portion or the concave portion of the body drum has a first rotational direction relative position rotatable relative to the drive rotating body, and a second rotational direction relative non-rotatable one direction substantially coaxially from the two rotation center axes. It has a shape and dimensions that can take a position, the first rotational direction relative position and the second rotational direction relative position in a state where the inner convex portion of the twisted concave portion enters the inner concave portion of the twisted convex portion. And a mounting means for removably mounting a process cartridge that can take any of the following.

A typical configuration according to the present invention for achieving the above object is as follows. In each of the above inventions, a hole is provided on the electrophotographic photosensitive drum side, and the hole is provided on the gear side provided on the apparatus main body side. A projection is provided.

[0027]

Embodiments of the present invention will be described below with reference to the drawings.

First Embodiment First, a process cartridge according to a first embodiment and an electrophotographic image forming apparatus to which the process cartridge can be detachably mounted will be specifically described with reference to FIGS. Here, as an order of description, first, the overall configuration of the process cartridge and the electrophotographic image forming apparatus used by mounting the process cartridge will be described with reference to FIGS. 1 to 6, and then FIGS. 3, 6, and 7 to 7 will be described. The configuration of a coupling which is a driving force transmission mechanism between the process cartridge and the image forming apparatus main body will be described with reference to FIG.

{Overall Configuration} FIG. 1 is a schematic view of an electrophotographic image forming apparatus A in which a process cartridge is detachably mounted, FIG. 2 is a side sectional view of a process cartridge B, and FIGS. FIGS. 5 and 6 are external perspective views, and are explanatory views of a mounting configuration for mounting the process cartridge to the apparatus main body.

As shown in FIG. 1, the electrophotographic image forming apparatus (laser beam printer in the embodiment) A irradiates a drum-shaped electrophotographic photosensitive member 7 with a laser beam based on image information from an optical system 1. Then, a latent image is formed on the photosensitive member, and the latent image is developed using toner to form a toner image. In synchronization with the formation of the toner image, the recording medium 2 (recording paper or the like) is transferred from the feeding cassette 3a to the pickup roller 3b, the feeding roller pair 3c, the conveying roller pair 3d,
The sheet is conveyed by conveying means 3 including a pair of registration rollers 3e and the like. Then, the toner image formed on the photosensitive drum 7 is transferred to the recording medium 2 by applying a voltage to the transfer roller 4 as a transfer unit. Then, the recording medium 2 is conveyed to the fixing unit 5 while being guided by the guide plate 3f. The fixing unit 5 includes a driving roller 5a and a fixing roller 5c having a heater 5b therein, and applies heat and pressure to the recording medium 2 passing therethrough to fix the transferred toner image on the recording medium 2. Then, the recording medium 2 is conveyed by a pair of discharge rollers 3g and 3h, and is discharged to a discharge section 6 through a reverse conveyance path.
The image forming apparatus A can also be manually fed by a manual tray 3i and a roller 3j.

On the other hand, the process cartridge B has an electrophotographic photosensitive member and at least one process means. Here, as the process means, for example, a charging means for charging an electrophotographic photosensitive member, a developing means for developing a latent image formed on the electrophotographic photosensitive member, a cleaning means for cleaning toner remaining on the surface of the electrophotographic photosensitive member And so on.

The process cartridge B of this embodiment has an electrophotographic photosensitive drum 7, a charging roller 8, an exposure opening 9, and a developing means 10, as shown in FIGS. The process cartridge B rotates the electrophotographic photosensitive drum 7 from the apparatus main body 13 by a coupling mechanism described later. Then, the surface is uniformly charged by applying a voltage to a charging roller 8 serving as a charging unit,
The information light from the optical system 1 is exposed to the photosensitive drum 7 through the exposure opening 9 to form a latent image.
Develop with 0.

The developing means 10 includes a toner storage section 10a.
Is sent out by the rotation of the sending member 10b,
While rotating the developing roller 10d containing the fixed magnet 10c, a toner layer provided with a triboelectric charge by the developing blade 10e is formed on the surface of the developing roller 10d.
The toner is transferred to the photosensitive drum 7 in accordance with the latent image to form a toner image and visualize the toner image. Then, a voltage having a polarity opposite to that of the toner image is applied to the transfer roller 4 provided in the apparatus main body 13 to transfer the toner image to the recording medium 2. The residual toner is removed from the photosensitive drum 7 after the transfer by the cleaning unit 11.
That is, the remaining toner is scraped off by the cleaning blade 11a. The scraped toner is
The squeeze sheet 11b collects the waste toner in the waste toner reservoir 11c.

The charging roller 8 is in contact with the photosensitive drum 7 and is driven to rotate by the photosensitive drum 7. Also,
The cleaning blade 11a is in contact with the photosensitive drum 7.

In the process cartridge B, a toner frame 12a having a toner storage portion 10a for storing toner and a developing frame 12b supporting a developing member such as a developing roller 10d are welded (in this embodiment, ultrasonic welding). ) To form a developing unit. Then, the developing unit is provided with a cleaning frame 12 for supporting the photosensitive drum 7, the charging roller 8, the cleaning means 11 and the like.
c is swingably connected to each other. The process cartridge B is removably mounted by a user on a cartridge mounting means provided on the apparatus main body 13 from a direction intersecting the longitudinal direction of the photosensitive drum 7 (see FIGS. 5 and 6). The cleaning frame 12c
A mounting guide 12c4 is provided near a bearing 12c2 described later.
Is provided. Further, the cleaning frame 12
The guide 24c is provided on the bearing 24 (of the convex portion 24) attached to the bearing 24c. In addition, this bearing 24, convex part 2
4a and the guide part 24c are integrally formed. The mounting guides 12c4 and 24c are guided by the guides 15a and 15c when mounting the process cartridge B.

As shown in FIG. 5, as the cartridge mounting means, a cartridge mounting guide member 15 is mounted on both left and right sides of a cartridge mounting space provided in the apparatus main body 13 so as to face each other (FIG. 5 shows one side surface). , FIG. 6 shows the other side surface), and the left and right guide members 15 are provided with guide portions 15a and 15c serving as guides when the process cartridge B is pushed in. Bosses and the like, which will be described later, protrudingly formed on both sides in the longitudinal direction of the cartridge frame are inserted into the guide portions 15a and 15c. In order to mount the process cartridge B on the apparatus main body 13, a cover 14 that can be opened and closed with respect to the apparatus main body 13 around the shaft 14a is opened. Then, the process cartridge B is mounted on the image forming apparatus A by closing the opening / closing cover 14. When the process cartridge B is removed from the apparatus main body 13, the opening / closing cover 14 is opened.

When the process cartridge B is mounted on the image forming apparatus A, as described later, the open / close cover 1 is opened.
The coupling on the cartridge side and the coupling on the main body side are coupled in conjunction with the closing operation of 4, so that the photosensitive drum 7 and the like can be rotated by being driven from the apparatus main body.

{Coupling and Driving Configuration} Next, a description will be given of the configuration of a coupling means which is a driving force transmission mechanism for transmitting a driving force from the image forming apparatus main body 13 to the process cartridge B.

FIG. 7 is a perspective view of a drum flange 16 as a driving force transmitting part integrally formed with a convex shaft 17, and FIG.
Denotes a photosensitive drum 7 to which the drum flange 16 is attached.
FIG. 9 is a partially cut perspective view of the photosensitive drum 7 shown in FIG.
Is a cross-sectional view showing a state in which is attached to the process cartridge B, FIG. 10 is an enlarged perspective view of the vicinity of the convex shaft 17 of the process cartridge B shown in FIG. 9, and FIG. 11 is a convex shaft 17 (process cartridge B) as a coupling. ) And a concave shaft 18 (provided on the apparatus main body 13)
FIG.

As shown in FIGS. 8 to 10 and 28, a cartridge-side coupling means is provided at one end in the longitudinal direction of the photosensitive drum 7 attached to the process cartridge B. In this coupling means, a coupling convex shaft 17 (cylindrical shape) is provided on a drum flange 16 fixed to one end of the photosensitive drum 7, and a convex portion 17 a is formed on the tip end surface of the convex shaft 17. I have. Note that the end face of the convex portion 17a is parallel to the end face of the convex shaft 17. The convex shaft 17 is fitted to a bearing 24 and functions as a drum rotation shaft. And in this embodiment,
The flange 16, the coupling convex shaft 17 and the convex portion 17a are provided integrally. A helical gear 16a is provided integrally with the flange 16 to transmit a driving force to the developing roller 10d inside the process cartridge. Therefore, as shown in FIG. 7, the drum flange 16 is an integrally molded product having a helical gear 16a, a convex shaft 17 and a convex portion 17a, and is a driving force transmitting component having a function of transmitting driving force.

The shape of the projection 17a is a twisted polygonal prism, more specifically, a substantially equilateral triangular prism twisted in the rotation direction of the shaft. The concave portion 18a fitted with the convex portion 17a is a hole twisted in the rotation direction of a shaft having a polygonal cross section. The cross section of the recess 18a is a substantially equilateral triangle. The recess 18a rotates integrally with the 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 17 a and the concave portion 18 a provided on the apparatus main body 13 are fitted, and the rotational force of the concave portion 18 a is reduced. When transmitted to the projection 17a, the projection 17a of a substantially equilateral triangular prism
And the inner surfaces of the recesses 18a abut equally, so that the axes coincide with each other (FIGS. 18A and 18B). Furthermore,
Due to the twisted shape, a force acts in a direction in which the concave portion 18 pulls the convex portion 17, and the convex end face 17 a 1 becomes concave portion 18 a 1
Abut. Therefore, the axial position and the radial position of the photosensitive drum 7 integrated with the projection 17a in the image forming apparatus main body 13 are stably determined.

Next, the hole 1 provided at the tip of the projection 17a will be described.
7, 8, 9, 10, 11, 18, 22, 28, 29, 3, 7 a 2, projections 18 a 4 provided inside recess 18 a, and shapes of recess 18 a.
0, FIG. 31, FIG. 32, and FIG.

FIG. 18 is a cross-sectional view of the coupling convex and concave portions, FIG. 22 is a perspective view of the coupling convex and concave portions, and FIG.
8 is a perspective view of a coupling concave shaft, FIG. 29 is an axial sectional view of a coupling convex portion and a concave portion (showing a state at the time of driving transmission), and FIG. 30 is an axial sectional view of a coupling convex portion and a concave portion (convex portion). FIG. 31 shows a state before the engagement between the coupling protrusion and the concave portion), FIG. 31 shows a sectional view around the coupling convex portion and the concave portion (shows a state at the time of driving force transmission), and FIG. FIG. 33 is a sectional view (showing a state at the time of standby) and FIG. 33 is a sectional view (at the time of driving force transmission) around a coupling convex portion and a concave portion showing another embodiment. FIGS. 31 to 32 show a state where the process cartridge B is mounted on the apparatus main body 13.

As shown in the above-described drawings, in the present embodiment, a hole 17a2 is provided at the tip of the projection 17a.
The inner surface of the hole 17a2 is inclined inward from the distal end toward the back. It is a so-called “mortar” shape.
The hole 17a2 has a circular cross section and is provided substantially coaxially with the projection 17a. The hole 17a2 is provided on the bottom surface of the convex portion 17a (the coupling convex portion 1).
7).

A hole is also provided on the bottom surface of the hole 17a2.
6.

On the other hand, the projection 18a
4 are provided. The projection 18a4 has a so-called “mountain shape” that is inclined outward from the distal end toward the back. The projection 18a4 has a circular cross section and is provided substantially coaxially with the coupling concave shaft 18. The projection is provided on the bottom surface of the concave portion 18a and projects slightly inward from the distal end surface of the concave shaft 18.

When the process cartridge B is mounted on the apparatus main body 13 and the cover 14 is closed, the projection 18a4 enters the inside of the hole 17a2. At this time, there is play between the outer peripheral surface of the projection 18a4 and the inner peripheral surface of the hole 17a2 (see FIGS. 18 (a) and (b), FIGS. 29 and 31 to 33). As shown in each figure, when driving is transmitted, the entire outer peripheral surface of the projection 18a4 and the hole 17a
2 has a play with the entire inner peripheral surface (FIG. 18 (b),
29, 31, and 33). Therefore, the projection 18a4 and the hole 17a2 do not affect the drive transmission. On the other hand, during standby (during non-driving force transmission), a part of the outer peripheral surface of the projection 18a4 comes into contact with a part of the inner peripheral surface of the hole 17a2 (see FIGS. 18A and 32).

As shown in FIGS. 29, 30, and 31, the relationship between the hole 17a2 and the projection 18a4 is such that the gap in the radial direction when the convex shaft 17 and the concave shaft 18 are connected to each other is as follows.
A gap between the convex portion 24a (described later) and the main body guide concave portion 15d (described later), and the coupling convex portion 17a and the concave portion 18
a is less than or equal to the radial gap with
1.0).

That is, the coupling convex portion 17a and the concave portion 18
S, the gap between the projection 24a and the main body guide recess 15d is T, and the hole 17 in the end face of the projection 17a is S.
The radial gap in the state where the convex shaft 17 and the concave shaft 18 of the a2 and the projection 18a4 inside the concave portion 18a are connected to each other is U
, The relationship of S ≧ T ≧ U is established.

Further, as shown in FIGS. 29 and 30, when the gap in the radial direction between the entrance of the hole 17a2 and the tip of the projection 18a4 in this embodiment is V, V ≧ S. From this, when the coupling convex portion 17a and the concave portion 18a are coupled, the hole 17a2 on the end face of the convex portion 17a and the concave portion 18a
Does not interfere with the projections 18a4 inside.

Further, regarding the shape of the concave portion 18a,
This will be described with reference to FIGS. 18 (a) and (b), FIGS. 28, 31, 32, and 33.

The concave portion 18a fitted with the convex portion 17a has
The hole is twisted in the direction of rotation of the polygonal shaft as a whole.
That is, it functions as a twisted hole in terms of drive transmission. Therefore, the convex portion 17a has a hole shape in which the cross section of the portion in contact with the convex portion 17a is twisted in the rotation direction of the polygonal shaft. However, the portion not in contact with the convex portion 17a is
The shape is extended outward and along the outer periphery of the concave shaft 18.
Thereby, the thickness of the portion of the concave shaft 18 where the concave 18a is provided is made to be as uniform as possible over the entire peripheral surface of the concave shaft 18. Incidentally, specifically, the concave portion 18a
Has a substantially equilateral triangle in cross section at a portion that comes into contact with the convex portion 17a, and has an arc shape 18a3 along the outer periphery (circle) of the concave shaft 18 except for this portion.

Next, the effects based on the above-described configurations will be described.

First, since the convex portion 17a is an integrally molded product made of resin, by providing a hole 17a2 on the end face of the convex portion 17a, variation in resin temperature and pressure fluctuation in the molding die are suppressed, and Can be reduced, and the shape accuracy of the convex portion 17a can be stabilized.

Further, since the concave portion 18a is also an integrally molded product made of resin, the portion other than the contact portion of the concave portion 18a with the convex portion 17a is formed into an arc shape along the outer periphery of the concave shaft 18, thereby forming the concave portion. Variation in resin temperature and pressure fluctuation in the mold can be suppressed, shrinkage after molding can be reduced, and the shape accuracy of the concave portion 18a can be stabilized. From this, it is possible to minimize the backlash of the contact point and the rotation unevenness of the coupling drive due to the load fluctuation during the rotation of the process cartridge B, and to further improve the rotation accuracy of the photosensitive drum 7. Was completed.

Next, the effect brought about by the coupling of the hole 17a2 and the projection 18a4 will be described.

First, as described above, the relationship between the entrance of the hole 17a2 and the tip of the projection 18a4 is that the radial gap is equal to or greater than the gap between the convex portion 24a and the main body guide concave portion 15d. It does not hinder the match. Further, the relationship between the hole 17a2 and the projection 18a4 is that the radial gap when the convex shaft 17 and the concave shaft 18 are coupled is equal to or less than the radial gap between the coupling convex portion 17a and the concave portion 18a. Therefore, even when the process cartridge B is vibrated when the process cartridge B is mounted or mounted on the apparatus main body 13, the contact portion between the coupling convex portion 17a and the concave portion 18a is prevented from being damaged. I can do it. That is, as described above, a part of the outer circumferential surface of the projection 18a4 and the hole 17a
2 is in contact with a part of the inner peripheral surface (FIG. 18 (a),
And FIG. 32). Therefore, even if the apparatus (printer or the like) is moved while the process cartridge is mounted, the protrusions 1a are formed by the holes 17a2 and the projections 18a4.
Since the radial movement of the recess 7a and the recess 7a is restricted, it is possible to prevent the projection 17a and the recess 18a from being damaged by vibration or the like.

The provision of the projection 18a4 in the recess 18a allows the process cartridge to be removed from the apparatus main body during assembly work at the factory, when the process cartridge is mounted on the apparatus main body, or for maintenance of the apparatus main body. Foreign matter can be prevented from entering the concave portion 18a when it is removed. Therefore, it is possible to prevent the concave portion 18a from being damaged.

In the present embodiment, the photosensitive drum 7
When viewed from the side, the twisting direction of the projection 17a is opposite to the rotation direction of the photosensitive drum 7 from the root to the tip of the projection 17a, and the twisting direction of the recess 18a is from the entrance of the recess 18a. In the opposite direction towards the inside,
The torsion direction of the helical gear 16a of the drum flange 16 described later is opposite to the torsion direction of the projection 17a.

The convex portion 17a and the concave portion 18a are
As shown in FIG. 18, the diameter of the circumscribed circle R0 of the triangular prism as the convex portion 17a = d0, the diameter of the inscribed circle R1 of the space having the triangular section as the concave portion 18a = d1, and the circumscribed circle R2.
When the diameter of d = d2, there is a relationship of d1 <d0 <d2.

More specifically, preferred examples of the numerical value range are as follows: d0 = about 3 mm to 70 mm, d1 = about 3 mm to 70 mm, and d2 = about 3 mm to 70 mm. Then, a size that satisfies the above-described relationship may be appropriately selected from this numerical range. In this embodiment, d0 is about 16 mm, d1 is about 9.5 mm, and d2 is about 17.5 mm. The amount of twist of the projection 17a is 1 ° to 15 ° in the rotational direction with respect to the axial length of about 1 mm of the projection 17a. Specifically, in the present embodiment, the shaft is twisted at a rate of about 7.5 ° in the rotational direction with respect to the length of the axis of about 1 mm.

The amount of twist of the concave portion 18a is also substantially
This is the same as the amount of twist of the convex portion 17a described above.

Further, specific examples of the sizes of the holes 17a2 and the projections 18a4 are as follows.

The diameter of the tip side of the hole 17a2 is about 1.0 mm to 50.0 mm (about 7.5 mm in this embodiment).
mm) The diameter of the bottom side of the hole 17a2 is about 1.0 mm to 50.0 mm (about 5.5 mm in the present embodiment).
mm) The depth of the hole 17a2 is about 1.0 mm to 30.0 mm (about 4.5 in this embodiment).
mm) The diameter of the tip side of the hole 18a4 is about 1.0 mm to 50.0 mm (about 4.5 mm in the present embodiment).
mm) The diameter of the root side of the hole 18a4 is about 1.0 mm to 50.0 mm (about 6.5 mm in the present embodiment).
mm) The length (projection amount) of the hole 18a4 is about 1.0 mm to 30.0 mm (about 4.0 mm in the present embodiment).
mm)

However, the shapes and sizes of the convex portions 17a and the concave portions 18a are not limited to the above-described embodiment, but may be selected as appropriate. For example, as shown in FIG. 11, the hole 17a2 may be a hole having a triangular cross section, and the protrusion 18a4 may be a triangular prism slightly smaller than the hole.

However, the present invention is not limited to the above numerical values and numerical value ranges, and may be appropriately selected.

Here, the number of the contact points for determining the theoretical three-dimensional sectional position is three, and the convex portion 1 as in the present embodiment is used.
When the shape of the concave portion 7a and the concave portion 18a is a substantially equilateral triangular prism, the vertex of the substantially equilateral triangle of the convex portion 17a abuts on the condition that the cross section of the concave portion 18a is equal to the inner surface of the substantially equilateral triangular space. Accordingly, it is possible to minimize the backlash of the contact point and the uneven rotation of the coupling drive due to the load fluctuation during the rotation of the process cartridge B, and it is possible to improve the rotation accuracy of the photosensitive drum 7. (See FIG. 18). Here, the convex shaft 17 and the convex portion 17a are arranged so that the drum flange 16 is positioned coaxially with the axis of the photosensitive drum 7 when the drum flange 16 is attached to one end of the photosensitive drum 7. It is provided in. Reference numeral 16b denotes a fitting portion which is fitted to the inner surface of the drum cylinder 7a when the drum flange 16 is mounted on the photosensitive drum 7. The drum flange 16 is provided on the photosensitive drum 7.
It is attached by "caulking" or "adhesion". The photosensitive drum 7b is coated around the drum cylinder 7a (see FIGS. 8 and 9).

The other end of the photosensitive drum 7 has
A drum flange 25 is fixed. The drum flange 25 has a drum shaft 25 a and a spur gear 25.
b is integrally molded (see FIG. 9).

It should be noted that the process cartridge B is
3, the drum shaft 25a (bearing 12c2)
Is fitted into a U-shaped groove 15b (see FIG. 5) of the apparatus main body 13, and a spur gear 25b formed integrally with the flange 25 transmits a driving force to the transfer roller 4 (see FIG. 5). (Not shown).

The drum flanges 16 and 25 may be made of polyacetal, polycarbonate, polyamide, or the like.
And polybutylene terephthalate
hthalate). However, other materials may be appropriately selected and used.

Around the convex portion 17a of the coupling convex shaft 17 of the process cartridge B, a circular convex portion 24a concentric with the convex shaft 17 is provided on the cleaning frame 12c (FIG. 3, FIG. 3). 9). The projection 24a protects the coupling projection 17a when the process cartridge B is attached or detached, and protects the coupling projection 17a from damage or deformation due to external force. Thus, it is possible to prevent rattling and vibration during coupling driving due to damage to the projection 17a.

Further, the convex portion 24a can also serve as a guide member when the process cartridge B is attached to and detached from the image forming apparatus main body 13. That is, when the process cartridge B is mounted on the main body A, the convex portion 24a comes into contact with the main body side guide portion 15c, and the convex portion 24a functions as a guide member when the process cartridge B is mounted on the mounting position. To facilitate attachment and detachment of the process cartridge B to and from the main body 13. When the process cartridge B is mounted at the mounting position, the convex portion 24a is supported by the concave portion 15d provided in the guide portion 15c. And
When the coupling convex shaft 17 and the concave shaft 18 are aligned by receiving the drive during the image formation, the convex portion 24a becomes the U groove 15d.
Rises slightly (about 0.3mm to 1.0mm),
The gap between the convex portion 24a and the main body guide portion 15a (the concave portion 15d) is smaller than the radial gap between the coupling convex portion 17a and the concave portion 18a. Accordingly, the coupling convex portion 17a and the concave portion 18a can be engaged with the process cartridge B mounted on the main body 13. In addition, a concave portion 18a is provided to face the U groove 15d. Further, the shape of the convex portion 24a is not limited to the circular shape shown in the present embodiment,
c as long as it can be supported by the U-groove 15d, and may be, for example, an arc shape. Further, in the present embodiment, an example is shown in which the bearing 24 for rotatably supporting the shaft portion 17 and the circular convex portion 24a are integrally molded and screwed (not shown) to the cleaning frame 12c (FIG. 9), bearing 24 and convex portion 24a
May be separate.

In this embodiment, the drum shaft 25a is fitted to a bearing portion 12c2 provided on the cleaning frame 12c (see FIGS. 4 and 9), and the bearing mounted on the cleaning frame 12c is provided. The photosensitive drum 7 is mounted on the cleaning frame 1 of the process cartridge B in a state where the convex shaft 17 is fitted to the inner surface of the cleaning cartridge 1.
2c. Then, the photosensitive drum 7 rotates around the shafts 17 and 25a. In this embodiment, the photosensitive drum 7 is attached to the cleaning frame 12c so as to be movable in the thrust direction. This is because the mounting tolerance was considered. However, the present invention is not limited to this, and the photosensitive drum 7 may not be movable in the sliding direction.

Further, the photosensitive drum 7 and the flange 1
6, there is a relationship as shown in FIG. That is, the outer diameter of the photosensitive drum 7 (the outer diameter of the cylinder 7a) = D1, the helical gear root diameter = G, the photosensitive drum bearing diameter (the outer diameter of the shaft 17 and the inner diameter of the bearing 24) =
F, diameter of the circumscribed circle of the coupling convex portion = C, diameter of the fitting portion of the photosensitive drum 7 with the drum flange 16 (drum inner diameter) = D2
Then, there is a relationship of D1> F ≧ C and G> D2.

The sliding load torque at the bearing portion can be reduced by D1> F, and when the flange portion is formed according to the relationship of F ≧ C, the mold is normally divided in the direction of arrow H in the drawing. Since there is no undercut portion, the mold configuration can be simplified.

Further, since the shape of the gear portion is provided on the left mold in FIG. 6 due to the relationship of G> D2, the right mold having a coupling shape and a complicated mold structure can be simplified. This has the effect of improving the durability of the mold.

The dimensional relationship between the convex shaft 17 and the concave shaft 18
Is reversed, that is, the concave portion 18 is provided on the photosensitive drum side.
a, a convex portion 17a is provided on the apparatus body side, and a concave portion 18a is provided.
The same effect can be obtained by setting the same relationship when the circumscribed circle diameter of the polygon is C = C.

More specifically, a preferred example of the numerical range is as follows: D1 = about 10 mm to 60 mm, G = about 10 mm to 70 mm,
F = about 5 mm to 70 mm, C = about 3 mm to 70 mm, D2 = about 9
It is preferably about mm to 59 mm. Then, a size that satisfies the above relationship may be appropriately selected from this numerical range. In this embodiment, in particular, D1 = about 30 mm, G = about 3
1 mm, F = about 16 mm, C = about 14 mm, D2 = about 28 mm. However, the present invention is not limited to the above numerical values and numerical value ranges, and may be appropriately selected.

On the other hand, the image forming apparatus main body 13 is provided with a main body coupling means. The main body coupling means is provided with a coupling concave shaft 18 at a position coinciding with the photosensitive drum rotation axis when the process cartridge B is inserted.
(Cylindrical shape) is provided (see FIGS. 6 and 13). As shown in FIG. 12, the coupling concave shaft 18 has a large-diameter gear 34 for transmitting the driving force of the motor 30 to the photosensitive drum 7.
The drive shaft is integrated with the drive shaft. (And this concave shaft 18
Is a rotation center of the gear 34 and is provided so as to protrude from a side end of the gear 34 (see FIGS. 13 and 14). In the present embodiment, the large-diameter gear 34 and the coupling concave shaft 18 are used.
Is formed by integral molding.

The gear 34 on the main body side is constituted by a helical gear. When the driving force is transmitted from the helical gear 20 fixed to the shaft 30 a of the motor 30. In addition, there is a tooth having an inclination angle such that a thrust for moving the concave shaft 18 in the direction of the convex shaft 17 is generated. Thus, when the motor 30 is driven at the time of image formation, the concave shaft 18 moves in the direction of the convex shaft 17 by the thrust and the concave 18
a engages with the convex portion 17a. The concave portion 18 a is provided at the tip of the concave shaft 18 and at the center of rotation of the concave shaft 18.

In this embodiment, the driving force is transmitted directly from the gear 20 fixed to the motor shaft 30a to the gear 34. However, the gear train is used to reduce and transmit the driving force, or the belt and the pulley, A roller pair, a timing belt and a pulley may be used.

Next, a configuration in which the concave portion 18a and the convex portion 17a are fitted together with the closing operation of the opening / closing cover 14 will be described with reference to FIGS.

FIG. 15 is a view of the photosensitive drum 7 as viewed from the axial direction. An outer cam 35 and an inner cam 36 (see FIG. 17) are arranged between the gear 34 and the photosensitive drum 7 (not shown). The moving means is constituted by connecting the cover 14 of the image forming apparatus and the outer cam 35 with a rod 37. Also, 40
Is a side plate provided on the apparatus main body 13. FIG.
In FIG. 17, reference numeral 34 a denotes a shaft supporting portion for supporting the gear 34 to the side plate 39.

FIG. 16 is a view of FIG. 15 as viewed from the right. When the cover 14 is closed, the rod 37, the outer cam 35 and the like are in the positions shown in the drawing, and the coupling convex portion 17a and the concave portion 18a are engaged. The driving force of the gear 34 can be transmitted to the photosensitive drum 7. And cover 1
When the outer cam 4 is opened, as shown in FIG.
The gear 34 moves in a direction away from the photosensitive drum 7 by the contact between the inner cam 36 and the inner cam 36. At that time, gear 3
4 and the coupling concave shaft 18 are pushed by the outer cam 35, and similarly move while pressing the spring 38 attached to the fixed plate 39, the concave portion 18a is separated from the convex portion 17a, and the coupling is released. Then, the cartridge B becomes detachable.

Conversely, when the cover 14 is closed, the cam 35 rotates in the reverse direction and is pushed by the spring 38, so that the gear 34 is set again to the position shown in FIG. With such a configuration, the cartridge B
Can be made detachable and drivable according to the opening and closing of the cover 14.

As described above, in this embodiment, when the process cartridge B is attached to or detached from the apparatus main body 13, the cover 1
Release 4. Then, in conjunction with the opening and closing of the cover 14, the concave portion 18a moves in the horizontal direction (the direction of the arrow j).
Therefore, when the process cartridge B is attached to and detached from the apparatus main body 13, the coupling (17a, 18a) between the process cartridge B and the apparatus main body 13 is not connected. They are not linked. Accordingly, the process cartridge B can be smoothly attached to and detached from the apparatus main body 13. In the present embodiment, the concave portion 18a is
Is pressed in the direction of the process cartridge B. Therefore, even when the projections 17a and the recesses 18a mesh with each other, even if the projections 17a and the recesses 18a collide with each other and do not mesh well, the two are instantly meshed by the rotation of the recess 18a.

Next, the shapes of the convex portion 17a and the concave portion 18a which are the engaging portions of the coupling means will be described.

Although the coupling concave shaft 18 provided on the apparatus main body 13 is movable in the rotation axis direction as described above, it is positioned so as not to move in the rotation radius direction (radial direction). . On the other hand, the process cartridge B is mounted on the apparatus main body 13 so as to be movable in the longitudinal direction of the photosensitive drum 7 and in the radial direction of rotation of the photosensitive drum 7 (radial direction).

That is, when the process cartridge B is mounted on the apparatus main body 13, a portion of the drum shaft 25a (see FIGS. 4 and 9) formed on the flange 25 attached to the other end of the photosensitive drum 7 in the longitudinal direction (bearing 12c2). Is the device body 13
Gears (see FIG. 5) which fit into the receiving portion (U-groove) 15b (see FIG. 5), and are fitted and positioned without any gap, and the spur gear 25b formed integrally with the flange 25 transmits the driving force to the transfer roller 4. (Not shown). On the other hand, on one end side (drive side) in the longitudinal direction of the photosensitive drum 7, a convex portion 24a provided on the cleaning frame 12c is supported by a concave portion 15d provided on the apparatus main body 13. When the cover 14 is closed, the concave portion 18a moves horizontally and enters the convex portion 17a (see FIG. 18A).

Next, positioning and drive transmission are performed on the drive side (coupling side) as follows.

First, when the main body drive motor 30 rotates,
The coupling concave shaft 18 moves in the direction of the coupling convex shaft 17 (the direction of arrow d in FIG. 13), and the convex portion 17a and the concave portion 18a
(In this embodiment, the projections 17a and the recesses 18a are substantially equilateral triangles, so that they are in phase with each other every 120 °). (From the state shown in FIG. 17 to the state shown in FIG. 16).

At the time of this coupling engagement, the projection 17a
As shown in FIG. 18 (a), there is a difference in the size of the substantially equilateral triangle between the two when the hole enters the concave portion 18a. Is large, so it enters smoothly with a gap. Thus, the positioning accuracy of the coupling convex shaft 17 and the coupling concave shaft 18 may be in a rough state.

In this embodiment, the circular projection 24a is used.
Is larger than the protrusion amount of the protrusion 17a (see FIG. 9). Therefore, the convex portion 17a and the concave portion 18a
When the two are engaged with each other, the inner surface of the circular convex portion 24a is fitted with the outer peripheral surface of the coupling concave shaft 18, and functions as a guide when the two are engaged.

When the image is formed, the convex portion 17a is
When the coupling concave shaft 18 rotates in a state where the coupling concave shaft 18a has entered the inner surface 1a of the concave portion 18a, as shown in FIG.
8a1 and three ridge lines 17a1 of a substantially equilateral triangular prism of the convex portion 17a
And the driving force is transmitted. At this time, the convex shaft 17 instantaneously moves so that the inner surface 18a1 of the concave portion 18a and the ridge line 17a1 of the convex portion 17a abut equally (from the state shown in FIG. 18A to the state shown in FIG. 18B). Becomes). Since the convex portion 17a and the concave portion 18a are substantially equilateral triangles, the axes of the convex shaft 17 and the concave shaft 18 coincide with each other in a state where the contact force is uniform. That is, the protrusion 17
When a enters the concave portion 18a, the rotational center X1 of the convex portion 17a and the rotational center X2 of the concave portion 18a are displaced from each other (FIG. 18A). When the concave portion 18a starts rotating and comes into contact with the three ridge lines 17a1 of the convex portion 17a, the rotational centers X1 and X2 substantially match.

With the above configuration, the coupling shafts 17 and 18 are automatically substantially aligned when the motor 30 is driven. Further, when a driving force is transmitted to the photosensitive drum 7, a rotational force is generated in the process cartridge B, and the rotational force causes the contact portion 12c1 provided on the upper surface of the cleaning frame 12c of the process cartridge B (see FIGS. 3 and 4). ) Abuts against an abutting portion 13 a (see FIG. 1) fixed to the image forming apparatus main body 13, and the position of the process cartridge B with respect to the image forming apparatus main body A is determined.

Further, at the time of non-driving (at the time of non-image formation), a gap is provided in the rotational radial direction (radial direction) between the convex portion 17a and the concave portion 18a. The process cartridge can be easily attached to and detached from the printer. Further, at the time of driving, the contact force at the above-described coupling engagement portion is stabilized, so that rattling and vibration at this portion can be suppressed.

In the present embodiment, the shapes of the coupling projections and the recesses are substantially equilateral triangles. However, it goes without saying that the same effect can be obtained if the coupling projections and depressions are approximately regular polygons. Further, the positioning can be performed more accurately if it is a substantially regular polygonal shape. However, the shape is not limited to this, and for example, a polygonal shape or the like may be used as long as it can be drawn and meshed.

Furthermore, when the coupling convex portion and the concave portion are compared, the convex portion is easily damaged in shape, and the strength is inferior to the concave portion. For this reason, in this embodiment, a coupling convex portion is provided on the replaceable process cartridge B, and a coupling concave portion is provided on the image forming apparatus main body 13 requiring higher durability.

Here, the above-described embodiment will be summarized as follows using the process cartridge B as an example. The process cartridge B of the present embodiment includes a motor 30
An apparatus body gear 34 for receiving the transmission of the driving force from the motor, and provided at a central portion of the apparatus body gear;
It has a twisted hole 18a having a polygonal cross section that rotates integrally with the apparatus body gear, and is detachable from the apparatus body 13 of the electrophotographic image forming apparatus A that forms an image on the recording medium 2. The process cartridge according to the present embodiment includes:
Electrophotographic photosensitive drum 7 and process means (charging roller 8, developing roller 1) acting on the electrophotographic photosensitive drum
0, a cleaning blade 11a) and a twisted polygonal column projection (projection 17) provided at one longitudinal end of the electrophotographic photosensitive drum and fitted into the polygonal twisted hole.
a), when the process cartridge B is mounted on the apparatus main body 13, the main body gear 34 rotates with the projection 17 a of the polygonal column fitted into the twisted hole 18 a having a polygonal cross section. Then, the projection 17a is moved to the hole 1
While being pulled in the direction 8a, the rotational force of the main gear 34 is transmitted to the electrophotographic photosensitive drum 7.

A hole 17a2 is formed on the end face of the projection 17a.
Are provided and are fitted with play to the projections 18a4 of the concave portions 18a.

The projection 17a is provided at a tip end of a shaft portion 17 projecting outward from the center of rotation of the drum 7 in the longitudinal direction of the drum. Here, the shaft portion rotatably supports the drum 7 on the cartridge frame 12c.

The shaft 17 is provided at the center of the helical gear 16a, and the electrophotographic apparatus is provided on the opposite side of the helical gear 16a from the shaft. An engagement portion 16b for engaging with the inner surface of the photoconductor drum 7 is provided. Here, the protrusion 17a, the shaft 17,
The helical gear 16a and the engaging portion 16b are integrally formed of resin. The helical gear transmits a rotational force to the developing roller 10a as the process means.

Further, a circular outer wall 24a provided surrounding the polygonal column projection 17a or an arcuate outer wall provided along a part of the polygonal column projection is provided. Here, the outer wall 24a serves as a guide when the hole 18a and the projection 17a are relatively moved and fitted.

The outer diameter of the electrophotographic photosensitive drum 7 is D1, the outer diameter of the shaft 17 is F,
Assuming that the diameter of the circumscribed circle 7a is C, the relationship is D1> F ≧ C.

The outer diameter of the shaft portion 17 is F, the diameter of a circumscribed circle of the projection 17a of the polygonal column is C, the root diameter of a gear 16a provided on the electrophotographic photosensitive drum 7 is G, Assuming that the inner diameter of the electrophotographic photosensitive drum 7 is D2, G>
D2 and G> F ≧ C.

If the outer diameter D1 of the electrophotographic photosensitive drum 7 and the root diameter of the gear 34 of the apparatus main body are L, it is preferable that L is about 1.0 to 5.0 times D1. . This relationship may be appropriately selected in consideration of the space of the apparatus main body, desired image quality, and the like. The present invention is not limited to this numerical range. Incidentally, in this embodiment, it is about three times.

The module of the apparatus body gear 34 has a size of about 0.4 to 0.7. The device body gear 3
The tooth root circle diameter L of No. 4 is about 30 mm to 150 mm, and the number of teeth of the apparatus body gear 34 is about 40 to 400 teeth. These values may be appropriately selected in consideration of the space of the apparatus main body and the desired image quality. The present invention is not limited to this numerical range. In this embodiment, the gear 34 is used.
Is about 0.5, L is about 100 mm, and the gear 34 has 200 teeth.

Here, the positioning of the process cartridge B with respect to the apparatus main body 13 at the time of image formation (at the time of driving transmission) is summarized as follows.

First, during non-image formation (non-drive), the process cartridge B is positioned with the bearing 12c2 fitted in the U groove 15b. The convex portion 24a is simply supported by the receiving portion 15d, and at the same time, the concave shaft 18
After moving in the direction of the photosensitive drum 7, the projection 18a4 also receives the hole 17a2, and roughly regulates the position of the process cartridge B in the apparatus main assembly A. At the time of image formation (at the time of drive transmission), the process cartridge B
a is drawn to the concave portion 18a provided in the apparatus main body 13, and the convex portion 17a and the concave portion 18a are positioned in a state of being engaged with each other. That is, at the time of image formation, the process cartridge B is positioned at one end in the longitudinal direction of the photosensitive drum 7 by the U groove 15b and at the other end by the recess 18a. Here, in the present embodiment, the photosensitive drum 7 can be moved in the longitudinal direction (about 0.1 mm to
(About 1.0 mm). Therefore, the protrusion 1
7a is drawn toward the recess 18a, the end 16c (FIGS. 7, 8, 9) of the drum flange 16 is brought into contact with the bearing 24.
Abuts the end 24b. Also, in consideration of assembly tolerance,
The process cartridge B mounted movably (about 0.1 to 3 mm) with respect to the main body side plates (mounting guide portions 15a and 15c) is drawn in the longitudinal direction and the radial direction of the photosensitive drum 7 (almost obliquely upward). Move to).
When the end 16c is in contact with the end 24b from the beginning, or when the photosensitive drum 7 has no play in the longitudinal direction, the process cartridge B immediately moves to the longitudinal direction of the photosensitive drum 7. Direction and radial direction (moving almost obliquely upward).

The process cartridge B receives a rotational force in the direction of rotation of the photosensitive drum 7 during image formation.
The contact portion 12c1 contacts the fixed portion 13a by this rotational force.

Therefore, the process cartridge B is positioned in the apparatus main body 13 in the longitudinal direction and the radial direction of the photosensitive drum 7 during image formation.

When the process cartridge B is pressed by an elastic member (for example, the embodiment shown in FIG. 21), the process cartridge B may not move in the longitudinal direction of the photosensitive drum 7 depending on the magnitude of the elastic force of the elastic member. It is conceivable that they do not move. However, even in this case, when the drive is transmitted, the process cartridge B moves in the radial direction of the drum 7 (moves substantially upward), and the apparatus main body 1
3 is performed. In this case, even when the photosensitive drum 7 has no play in the longitudinal direction, the process cartridge B is similarly positioned with respect to the apparatus main body 13.

[Second Embodiment] Next, the coupling convex shaft 1 will be described.
Another embodiment of the shape of the projection 17a of FIG. 7 will be described with reference to FIG. The basic configurations of the process cartridge and the image forming apparatus are the same as those of the first embodiment described above, and will not be described repeatedly, and members having the same functions as those of the first embodiment will be denoted by the same reference numerals. .

The coupling projection 17a shown in FIG. 19 is different from the above-described embodiment in that the shape of each of the item points 17a2 of the substantially regular polygonal prism shape (substantially equilateral triangle in FIG. 19) of the projection is chamfered. That is the point. This chamfer is shown in FIG.
19B or a shape in which vertices of a substantially regular polygon are linearly dropped as shown in FIG.

With the above-described configuration, it is possible to prevent the protrusion 17a from being crushed at the top when the process cartridge B is operated or when the coupling is engaged. Then, at the time of driving, bending or deformation due to insufficient strength of each term can be suppressed. Therefore, it is possible to prevent the accuracy of alignment between the convex shaft 17 and the concave shaft 18 from being lowered, and to suppress rattling and vibration at the coupling portion.

In FIG. 19A, if this shape is introduced as the shape of the convex portion 17a in FIG. 18B, the portion in contact with the inner surface of the concave portion can be easily understood.
It is not the outermost part of the shape of FIG. 9 (a) but a part slightly shifted therefrom (at each vertex). From the viewpoint of alignment accuracy, it is preferable that these three contacts form a substantially equilateral triangle.

Similarly, in FIG. 19B, it is preferable that the three contact points form a substantially equilateral triangle.

Similarly, also in the example of the polygonal column convex portion (polygonal concave portion), the fact that the convex portion and the concave portion substantially contact at three points and these three points form a substantially equilateral triangle means that the alignment accuracy is high. It is preferable from the viewpoint of.

In the case of FIG. 19A, each contact point is not one point but has a slight width. In this case, the central part of the width (or the end in the same direction of the width) is regarded as the contact point. Good.

[Third Embodiment] Next, another embodiment of the shape of the convex portion of the coupling convex shaft 17 will be described with reference to FIG. Note that the basic configurations of the process cartridge and the image forming apparatus are the same as those of the above-described embodiment, and therefore, duplicate description is omitted, and members having the same functions as those of the above-described embodiment are denoted by the same reference numerals.

In the above-described first embodiment, the flange 16 of the photosensitive drum 7 and the coupling convex shaft 17 are integrated. However, as shown in FIG. good.

As in this embodiment, the coupling convex shaft 1
If the flange 7 is provided separately from the flange 16, the coupling convex shaft 17 can be assembled into the engagement portion 16 b of the flange 16 by press fitting or the like after the photosensitive drum 7 with the flange 16 is assembled into the frame 12 c. The photosensitive drum 7
Need not be assembled diagonally to the frame 12c.

[Fourth Embodiment] Next, another embodiment of a structure for positioning a process cartridge to the image forming apparatus main body using the coupling structure of the present invention will be described with reference to FIG. Note that the basic configurations of the process cartridge and the image forming apparatus are the same as those of the above-described embodiment, and thus redundant description is omitted, and members having the same functions as those of the above-described embodiment are denoted by the same reference numerals.

As shown in FIG. 21, the image forming apparatus main body 1
3 is provided with an elastic member 13b for urging the process cartridge B in the rotation direction of the photosensitive drum 7.
The elastic member 13b abuts on the contact portion 12c3 of the cleaning frame 12c of the process cartridge B when the process cartridge B is mounted on the main body, and applies a rotational force to the process cartridge B in the same direction as the rotation direction of the photosensitive drum 7. (See FIGS. 3, 4, and 21). The process cartridge B to which the rotational force is applied tries to rotate in the rotation direction of the photosensitive drum 7 (clockwise direction in FIG. 21), but the contact portion 12c1 of the frame 12c and the main body contact portion 13a contact. Held in state. As a result, the process cartridge B urged in the rotation direction of the photosensitive drum 7 by the coupling driving force
Vibration in the rotation direction due to load fluctuations or the like in the inside can be prevented. In addition, two contact portions 12c3 are provided on the upper surface of the cleaning frame 12c, on one end side and the other end side in the longitudinal direction of the photosensitive drum 7 (FIG. 3, FIG.
(See FIG. 4).

[Fifth Embodiment] Another embodiment of the coupling structure of the present invention will be described with reference to FIG.

The basic configuration of the process cartridge and the image forming apparatus is the same as that of the above-described embodiment, and therefore, the description thereof will not be repeated, and members having the same functions as those of the above-described embodiment will be denoted by the same reference numerals. Attach.

In this embodiment, as shown in FIG. 22, the convex portion 17a of the coupling convex shaft 17 and the concave portion 18 of the concave shaft 18 are used.
In a, the cross section in the direction perpendicular to the shaft has a substantially square shape, and further has a shape twisted in the rotation direction of the shaft. Further, similarly to the first embodiment, a durable coupling recess 18 a is provided in the image forming apparatus main body 13. In this configuration, when the drive is transmitted while the coupling is engaged, the coupling concave shaft 18 causes the coupling shaft 17 to become convex due to the twisted shape.
Is generated in the direction of drawing the shaft in the axial direction, and the convex end face 17a1 of the coupling convex shaft 17 and the concave bottom face 18a1 abut (or the convex shaft end face 17b and the concave shaft end face 18b abut).

In this embodiment, the hole 17a2 has a rectangular cross section, and the projection 18a4 has a rectangular parallelepiped shape slightly smaller than the hole 17a2. Also in the present embodiment, a part of the concave portion 18a may be spread outward.

As a result, at the time of driving, the image forming apparatus main body A
In this case, the position of the process cartridge B is always constant in the coupling axial direction, so that the vibration of the process cartridge can be suppressed.

In this embodiment, the cross section of the coupling shaft in the direction perpendicular to the axis of the convex portion 17a and the concave portion 18a has a substantially square shape. However, the present invention is not limited to this, and the cross sectional shape is not limited to the coupling shape. Other twisted polygonal pillars that can engage the protrusions when the recesses rotate may be used.

When the process cartridge B is detached from the apparatus main body, if the motor 30 is driven in a direction opposite to the direction in which the image is formed, the thrust of the gears 34 and 33 constituted by the helical gears is used. , The coupling is automatically released. In this case, it is not necessary to provide the coupling release mechanism as described in the first embodiment.

[Sixth Embodiment] Next, another embodiment will be described with reference to FIG. The embodiment shown in FIG. 23 is different from the first embodiment in that no gear is provided on the drum flange 16.

In the coupling structure shown in FIGS. 23A and 23B, the main body side coupling means is made of polyacetal (P
The cartridge is constituted by a coupling shaft 17 made of OM), and the coupling means on the cartridge side to be engaged with this is constituted by a coupling shaft 18 made of POM. Around the coupling convex shaft 18, a cylindrical wall 24 concentric with the rotation center of the photosensitive drum 7 is provided integrally with the flange 16. Note that FIG. 23 (b) corresponds to FIG.
It is the arrow D and E figure of (a).

Around the convex shaft 18, a convex portion 18a
By providing the wall portion 24 having the same height as
The protrusion 18a does not protrude from the cartridge frame, so that the end of the protrusion 18a can be prevented from being damaged.

As described above, the cylindrical wall 2
Reference numeral 4 can be used as a guide for attaching and detaching the process cartridge B along the guide portion 15c (see FIG. 6) of the image forming apparatus A.

[Seventh Embodiment] Next, another embodiment will be described with reference to FIGS. In the embodiment described below, a concave shaft 117 is provided on a drum flange 116 provided on the photoconductor drum 7 and a large-diameter gear 121 provided on the apparatus main body 13 is opposite to the above-described embodiments. A shaft 118 is provided. With this, the rotation accuracy of the photosensitive drum 7 can be improved.

As shown in FIG. 24, also in the present embodiment, the convex portion 118 of the coupling convex shaft 118 having a substantially equilateral triangular prism.
a has a shape twisted in the rotation direction, and accordingly, the concave portion 117a of the coupling concave shaft 117 has a shape twisted in the rotation direction. And coupling concave shaft 1
A seating surface 117b is provided on an end surface of the device.

As described above, by forming the engaging portion into a shape twisted in the rotation direction, when the coupling convex shaft 118 rotates in the image forming direction (the direction of arrow c) in the engaged state, the coupling convex shaft is rotated. 118 is the concave shaft 117 and the seat 11
Pull until it hits 7b. As a result, the connection between the two becomes more reliable.

When removing the process cartridge B from the apparatus main body 13, as shown in FIG. 25, when the motor 119 is driven in the opposite direction (the direction of arrow d) from the image formation, a pinion composed of a helical gear is formed. The coupling of the coupling can be automatically released by the thrust between the gear 120 and the transmission gear 121.

In this embodiment, if the allowable transmission torque of the concave shaft 117 is smaller than the allowable transmission torque of the convex shaft 118, the damage of the convex shaft 118 can be prevented.

For example, the coupling concave shaft provided on the cartridge is made of polyacetal (POM), and the coupling convex shaft provided on the main body is made of zinc die-cast. With this configuration, if abnormal torque is generated, the allowable transmission torque of the coupling convex shaft on the main body side is large, so that the convex shaft is prevented from being damaged.

The above embodiment is the same as the first embodiment except that a concave shaft is provided on the drum flange and a convex shaft is provided on the gear of the apparatus main body. Therefore, in the embodiment in which the above-described embodiment is applied to an electrophotographic image forming apparatus, a process cartridge, a drive transmission component, and an electrophotographic photosensitive drum, in the first embodiment, the convex shaft provided on the drum flange is changed to the concave shaft. Alternatively, the concave shaft provided on the gear of the apparatus main body is replaced with a convex shaft, and the description of the first embodiment is cited.

For the sake of simplicity, the process cartridge will be described as an example. The motor 30 (119) and the device main body for receiving the driving force transmitted from the motor 30 (119) are composed of a helical gear 34 ( 121), the apparatus body has a twisted substantially triangular prism protrusion 118a provided at the center of the helical gear 34 (121), and the apparatus body rotates integrally with the helical gear. The process cartridge B is detachable from the apparatus main body 13 of the electrophotographic image forming apparatus A that forms an image on a medium. That is, the process cartridge B includes the cartridge frames 12a, 12b, 12
c, the electrophotographic photosensitive drum 7 (107), a charging roller 8 for charging the electrophotographic photosensitive drum 7 (107), and the electrophotographic photosensitive drum 7 (10).
7) a cleaning blade 11a for removing toner remaining on the electrophotographic photosensitive drum 7 (10);
Developing roller 10 for developing the latent image formed in 7)
and a twisted hole 117a provided at one longitudinal end of the electrophotographic photosensitive drum 7 (107) and having a substantially triangular cross section for fitting with the projection 118a. Here, the process cartridge B is moved to the apparatus main body 13.
The hole 117a, when mounted on the
When the helical gear 34 (121) rotates in a state in which the helical gear 34 (121) is fitted, the main body helical gear 34 (12) is pulled in a state where the hole 117a is drawn in the direction of the protrusion 118a.
The rotational force of 1) is applied to the electrophotographic photosensitive drum 7 (107).
Is transmitted to The hole 117a is provided in the shaft 17 provided in the center of the helical gear 16a (116a).
It is recessed at the tip of (117). The drum helical gear 16a (116a) transmits a rotational force to the developing roller 10d. Also,
The shaft portion 17 (117) is connected to the electrophotographic photosensitive drum 7
(107) is rotatably supported by the cartridge frame 112c. The drum of the hole 117 has a helical gear 16 (116a) and a shaft 17 (11
7) is a resin integrally molded product. When the outer diameter of the electrophotographic photosensitive drum 7 (107) is D1, the outer diameter of the shaft portion is F, and the diameter of the circumscribed circle of the hole 117a is C, the relationship is D1>F> C. .

The outer diameter of the shaft portion 17 (117) is F, the diameter of the circumscribed circle of the hole is C, the root diameter of the gear provided on the electrophotographic photosensitive drum is G, and Assuming that the inner diameter of the photographic photosensitive drum is D2, the relationship is G> D2 and G>F> C. The outer diameter of the electrophotographic photosensitive drum 7 (107) is D1 and the apparatus body gear 3
Assuming that the root diameter of the tooth 4 (121) is L, L is about 1.0 to about 5.0 times D1. Also, the module of the device body gear 34 (121) is about 0.4 to 0.7.
It is. Also, the root circle diameter L of the device body gear is about 30.
mm to 150 mm, and the number of teeth of the device body gear is about 40
Teeth ~ 400 teeth.

In the present embodiment, the photosensitive drum 7
When viewed from the side of (107), the twisting direction of the protrusion 118a is the same as the rotation direction of the photosensitive drum 7 (107) from the root to the tip of the protrusion 118a.
The torsion direction of the hole 117a is the same from the entrance of the hole 117a toward the inside, and the drum flange 16a (1
The twist direction of 16a) is opposite to the twist direction of the hole 117a.

[Eighth Embodiment] In the first embodiment, when the cover 14 is opened, the rod 3
Although the engagement between the coupling convex portion 17a and the concave portion 18a is released by operating the cam 7 and the cam 35, this coupling releasing configuration may be configured as shown in FIGS. 26 and 27.

That is, as shown in FIG. 26A, the opening / closing cover 14 has an arc-shaped release member 1 centered on the shaft 14a.
26, a cam portion 140a is formed at the distal end of the release member 140, as shown in FIG. Therefore, FIG.
As shown in (b), when the cover 114 is opened to remove the process cartridge B, the cam portion 140a enters between the wall portion 141, the concave shaft 18, and the integrated gear 34, and a side view of the gear 34 is illustrated. Extrude in the direction of arrow b at 27.
As a result, the concave shaft 18 is retracted from the wall portion 141 and disengaged from the coupling convex shaft 17 provided on the photosensitive drum 7, and the process cartridge B can be removed smoothly.

It is not necessary to limit the release member 140 to the open / close cover 14 as long as the member is operated when the process cartridge B is attached and detached. Further, when the drive transmission gear 34 is formed by a helical gear, the coupling can be released by the thrust of the helical gear without necessarily having the release member 140.

[Other Embodiments] In the first embodiment described above, an example is shown in which the coupling provided on the photosensitive drum is constituted by the convex shaft 17 and the coupling provided on the main body is constituted by the concave shaft 18. Even if the concave shaft and the convex shaft are exchanged between the photosensitive drum side and the apparatus main body side, the same effect on the rotation accuracy of the photosensitive drum can be obtained (see FIGS. 23 and 24). At this time, by configuring the allowable transmission torque of the concave shaft provided on the photosensitive drum to be smaller than the allowable transmission torque of the convex shaft provided on the apparatus main body, damage to the convex shaft provided on the apparatus main body can be prevented. Can be prevented.

For example, the concave shaft provided on the photosensitive drum is formed of polyacetal (POM), and the convex shaft provided on the apparatus body is formed by zinc die casting. With this configuration, if abnormal torque is generated, it is possible to prevent the coupling shaft provided on the main body from being damaged due to a large allowable transmission torque of the coupling shaft.

In the above-described embodiment, the protrusion 1
If a taper is formed at the front end of the recess 7a or at the entrance of the recess 18a, or both, the protrusion 17a and the recess 18a are formed.
Will be more smoothly combined.

Note that FIGS. 3, 6, 13, 14, and 2
In FIG. 0, FIG. 23, and FIGS. 24 to 27, the illustration of the hole 17a2, the projection 18a4, and the arc shape 18a3 is omitted. This is to avoid complicating the drawing.

Another embodiment is shown in FIGS. 34 and 35.
This will be described with reference to FIG. In the present embodiment, a lid that can be opened and closed is provided in the hole 17a2. According to the present embodiment, the hole 1
Foreign matter can be prevented from entering the inside of 7a2.

Since the basic constructions of the process cartridge and the image forming apparatus are the same as those of the first embodiment described above, a duplicate description will be omitted, and members having the same functions as those of the first embodiment will be omitted. Are assigned the same reference numerals.

In this embodiment, a cover 19 for closing the hole 17a2 on the end face of the projection 17a is provided. Lid 19
Has a portion 19b that fits the lid 19a and the inside 16c of the drum gear 16a, and a portion 19c that fits the spring 20. The drum gear 16 includes a spring receiving member 21.
Are attached by bonding or the like.

When the process cartridge B is not mounted on the apparatus main body 13, as shown in FIG.
Is urged by the spring 20, the fitting portion 19b comes into contact with the drum gear butting portion 16d, and in this state, the lid portion 19a
Closes the hole 17a2. When the process cartridge B is mounted on the apparatus main body 13, the lid 19a is pushed in the axial direction by the projection 18a4 of the main body gear shaft 18, the spring 20 is bent, and the projection 18a4 is in the hole 17a2.
Get into it.

In this embodiment, the same effects as those of the above-described embodiments can be obtained. Further, since the hole 17a2 is closed, the effect of preventing foreign matter from entering the hole 17a2 or the photosensitive drum 7 can be obtained. is there.

Although the process cartridge B described above is for forming a single-color image, the process cartridge is not only used for forming a single-color image, but also provided with a plurality of developing means and provided with a plurality of color images (for example, 2-color image, 3
The present invention can be suitably applied to a cartridge for forming a color image or a full color.

As the developing method, various developing methods such as a known two-component magnetic brush developing method, a cascade developing method, a touch-down developing method, and a cloud developing method can be used.

The electrophotographic photosensitive member includes, for example, amorphous silicon, amorphous selenium, zinc oxide, titanium oxide, organic photoconductor (OPC), and the like. As a method for mounting the photoconductor, a photoconductor is deposited or coated on a cylinder of an aluminum alloy or the like.

In the first embodiment described above, a so-called contact charging method is used. However, as another structure, a metal shield such as aluminum is provided around three sides of a conventionally used tungsten wire. It is a matter of course that a configuration may be used in which positive or negative ions generated by applying a high voltage to the tungsten wire are moved to the surface of the photosensitive drum, and the surface of the drum is uniformly charged.

The charging means may be of a blade type (charging blade), a pad type, a block type, a rod type, a wire type, or the like, in addition to the roller type.

As a method for cleaning the toner remaining on the photosensitive drum, the cleaning means may be constituted by using a blade, a fur brush, a magnetic brush or the like.

The process cartridge described above is
For example, an electrophotographic photosensitive member and at least one of the process means
It has one. Therefore, as an aspect of the process cartridge, in addition to the above-described embodiment, for example, an electrophotographic photosensitive drum and a charging unit are integrally formed into a cartridge and can be attached to and detached from the apparatus main body.
An electrophotographic photosensitive drum and a developing means are integrally made into a cartridge and made detachable from the apparatus main body. An electrophotographic photosensitive drum and a cleaning unit are integrally formed into a cartridge so that the cartridge can be attached to and detached from the apparatus main body. Further, there is a type in which an electrophotographic photosensitive drum and two or more of the above-mentioned process means are combined into a cartridge to be detachable from the apparatus main body.

That is, the above-described 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 into a cartridge, and this cartridge is detachably mountable to an image forming apparatus main body. is there. 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. The process cartridge can be attached to and detached from the apparatus main body by the user himself. Therefore, the maintenance of the apparatus main body can be performed by the user himself.

In the above-described embodiment, the photosensitive drum and the developing roller are formed into a cartridge, and an apparatus for forming an image by mounting the process cartridge is illustrated. However, the photosensitive drum and the developing roller are not formed into a cartridge. The present invention can be similarly applied to an image forming apparatus directly attached to the apparatus main body.

Further, in the above-described embodiment, a laser beam printer is exemplified as an image forming apparatus. However, the present invention is not limited to this. For example, another image forming apparatus such as an electrophotographic copying machine, a facsimile machine, or a word processor may be used. Of course, it is also possible to use.

As described above, by providing a hole in the end face of the coupling projection, variation in resin temperature and pressure fluctuation in the molding die is suppressed, and shrinkage after molding is reduced.
The shape accuracy of the projection can be stabilized. Furthermore,
Since the concave portion is also an integrally molded product, a part of the concave portion (other than the contact portion with the convex portion) is formed along the outer periphery of the concave shaft, so that the resin temperature variation and the pressure in the molding die are reduced. Variation can be suppressed, shrinkage after molding can be reduced, and the shape accuracy of the concave portion can be stabilized. From this, it is possible to minimize the backlash of the contact point and the rotation unevenness of the coupling drive due to the load fluctuation during the rotation of the process cartridge B, and to improve the rotation accuracy of the photosensitive drum 7. I can do it.

Also, a hole is provided on the end face of the projection, and a projection is provided inside the recess, and the projection is fitted with a gap, the radial gap between the coupling projection and the recess is S, and the gap between the projection and the body guide recess. Is defined as T, and when a gap in the radial direction in a state where the convex axis and the concave axis of the hole in the end face of the convex portion and the protrusion inside the concave portion are coupled to each other is U, the relationship of S ≧ T ≧ U is obtained. In addition, when the process cartridge is transported with the process cartridge mounted on the apparatus main body, the contact portion between the coupling convex portion and the concave portion can be prevented from being damaged.

When a gap in the radial direction between the entrance of the hole and the tip of the projection is V, V ≧ S. For this reason, when the coupling convex portion and the concave portion are coupled, the hole in the end face of the convex portion does not interfere with the projection inside the concave portion.

That is, the hole 17a2 on the end face of the projection 17a and the projection 18a4 inside the recess 18a are, as described above,
The relationship between the entrance of the hole 17a2 and the tip of the projection 18a4 is that the radial gap is the coupling convex portion 17a and the concave portion 18a.
Is not less than the radial gap between the projections 17a and the recesses 18a. Also, hole 1
The relationship between 7a2 and the projection 18a4 is that the convex shaft 17 and the concave shaft 18
Is smaller than the radial gap between the coupling convex portion 17a and the concave portion 18a. Therefore, for example, a state in which the process cartridge B is mounted on the apparatus main assembly A when not driven. When the process cartridge B vibrates, for example, when transported by a user or carried by a user, the contact portion between the coupling convex portion 17a and the concave portion 18a can be prevented from being damaged (see FIG. 32). Specifically, even if vibration occurs,
When the main body guide concave portion 15d receives the convex portion 24a and / or the projection 18a4 receives the hole 17a2, the coupling convex portion 17a and the concave portion 18a can be prevented from being damaged. In the direction indicated by the arrow, which is the mounting direction of the process cartridge, the projection 18a4 receives the hole 17a2, so that the coupling convex portion 17a and the concave portion 18a are formed.
Can prevent damage.

As described above, the rotation accuracy of the coupling drive transmission can be improved, and the positioning of the photosensitive drum shaft relative to the apparatus main body in the cross-sectional direction and the axial direction can be accurately performed during driving.

[0173]

As described above, according to the present invention, since the rotational accuracy of the drive transmission can be improved, the rotational accuracy of the electrophotographic photosensitive drum can be improved.

Further, according to the present invention, it was possible to surely transmit the driving force from the apparatus main body to the electrophotographic photosensitive drum.

Further, according to the present invention, when transmitting the driving force (at the time of image formation), the rotation center of the coupling provided on the apparatus main body and the coupling center provided on the electrophotographic photosensitive drum are controlled. The center of rotation could be substantially matched.

According to the present invention, when the driving force is transmitted (at the time of image formation), the electrophotographic photosensitive drum is pulled toward the apparatus main body side, so that the photosensitive drum and the process cartridge are moved toward the apparatus main body. The positioning accuracy could be improved.

According to the present invention, when no drive transmission is performed (during non-image formation), the connection of the drive force transmission mechanism between the apparatus main body and the process cartridge is cut off.
Thereby, the operability of taking out the process cartridge from the apparatus main body can be improved.

According to the present invention, since the projection is provided inside the concave portion, it is possible to prevent foreign matter from entering the inside of the concave portion.

Further, according to the present invention, by providing a hole in the end face of the projection, the shape accuracy of the projection can be improved even if the projection is manufactured by molding.

Further, according to the present invention, even if the concave portion is manufactured by molding, the shape accuracy of the concave portion can be improved by expanding the portion of the concave portion that does not contact the convex portion outward.

Further, according to the present invention, since the projection is provided inside the concave portion and the hole is provided at the tip of the convex portion, the projection enters the hole, so that the process cartridge remains mounted. Even if the device is transported or carried, it is possible to prevent the concave portion and the convex portion from being damaged.

[Brief description of the drawings]

FIG. 1 is a side sectional view of an electrophotographic image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a side sectional view of a process cartridge according to one embodiment of the present invention.

FIG. 3 is a perspective view illustrating a process cartridge according to an embodiment of the present invention.

FIG. 4 is an explanatory perspective view of a process cartridge according to an embodiment of the present invention.

FIG. 5 is a perspective view of a process cartridge mounting portion of an electrophotographic image forming apparatus main body according to an embodiment of the present invention.

FIG. 6 is a perspective view of a process cartridge mounting portion of the main body of the electrophotographic image forming apparatus according to the embodiment of the present invention.

FIG. 7 is a perspective view of a drum flange (a driving force transmitting component) according to an embodiment of the present invention.

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

FIG. 9 is a cross-sectional view of a coupling portion on a process cartridge side according to an embodiment of the present invention.

FIG. 10 is a perspective view of a coupling portion of the process cartridge according to one embodiment of the present invention.

FIG. 11 is a cross-sectional view illustrating a drive system of an electrophotographic image forming apparatus main body according to an embodiment of the present invention.

FIG. 12 is a cross-sectional view illustrating a drive system of an electrophotographic image forming apparatus main body according to an embodiment of the present invention.

FIG. 13 is a perspective view of a coupling provided on an apparatus main body and a coupling provided on a process cartridge according to an embodiment of the present invention.

FIG. 14 is a perspective view of a coupling provided on an apparatus main body and a coupling provided on a process cartridge according to an embodiment of the present invention.

FIG. 15 is a cross-sectional view illustrating a configuration of a cover and a coupling unit of the apparatus main body according to an embodiment of the present invention.

FIG. 16 is a side view illustrating a configuration around a coupling concave axis when the process cartridge is driven in the apparatus main body according to the embodiment of the present invention.

FIG. 17 is a side view illustrating a configuration around a coupling concave axis when the process cartridge is attached to / detached from the main body according to the embodiment of the present invention.

FIG. 18 is a sectional view of a coupling convex portion and a concave portion showing one embodiment of the present invention.

FIG. 19 is a cross-sectional view of a coupling protrusion showing one embodiment of the present invention.

FIG. 20 is a sectional view of a process cartridge side coupling portion according to an embodiment of the present invention.

FIG. 21 is a sectional view of an electrophotographic image forming apparatus according to an embodiment of the present invention.

FIG. 22 is a perspective view of a coupling convex portion and a concave portion according to an embodiment of the present invention.

FIG. 23 is a side sectional view and a plan view of a convex shaft of a twisted triangular prism provided in a process cartridge and a concave shaft provided in an apparatus main body according to an embodiment of the present invention.

FIG. 24 is a schematic cross-sectional view of a process cartridge according to an embodiment of the present invention.
FIG. 4 is a perspective view showing a twisted substantially triangular prism convex portion provided on the apparatus main body.

FIG. 25 is a perspective view showing a driving mechanism of the coupling shown in FIG. 24;

FIG. 26 is an explanatory diagram of an interlocking mechanism between an opening / closing cover and a driving unit according to an embodiment of the present invention.

FIG. 27 is an explanatory diagram of an interlocking mechanism between an opening / closing cover and a driving unit according to an embodiment of the present invention.

FIG. 28 is a perspective view of a coupling concave shaft.

FIG. 29 is an axial sectional view of a coupling convex portion and a concave portion (showing a state at the time of driving transmission).

FIG. 30 is an axial sectional view of a coupling convex portion and a concave portion (showing a state before the convex portion and the concave portion are engaged).

FIG. 31 is a cross-sectional view of the vicinity of a coupling convex portion and a concave portion (showing a state at the time of driving force transmission).

FIG. 32 is a cross-sectional view of the vicinity of a coupling convex portion and a concave portion (showing a state during standby).

FIG. 33 is a cross-sectional view (at the time of driving force transmission) around a coupling protrusion and a recess showing another embodiment.

FIG. 34 is a cross-sectional view of a coupling recess showing another embodiment.

FIG. 35 is a cross-sectional view of a coupling convex portion and a concave portion showing another embodiment.

[Explanation of symbols]

 Reference Signs List A Image forming apparatus B Process cartridge 1 Optical system 2 Recording medium 3 Conveying means 4 Transfer roller 5 Fixing means 6 Discharge unit 7 Photosensitive drum 8 Charging roller 9 Exposure opening 10 Developing means 11 Cleaning means 12a, 12b, 12c Frame 13 Image forming apparatus Main body 13a Main body side contact portion 14 Cover 14a Cover shaft 15 Cartridge detachable guide member 16 Photoreceptor drum flange 16a Gear portion 17 Coupling convex shaft 17a Coupling convex portion 17a2 hole 17b Convex end surface 18 Coupling concave shaft 18a Recess 18a1 Recess Bottom 18a4 Projection 24 Bearing 24a Bearing projection 25 Flange 30 Motor 34 Gear 35 Outer cam 36 Inner cam 37 Rod 38 Spring 39 Fixing plate

Claims (56)

[Claims] 1. A motor, an apparatus body gear for receiving a driving force transmitted from the motor, and a body recess formed by a twisted surface and provided substantially coaxially with the apparatus body gear. Inside the main body concave portion, the main body convex portion provided substantially coaxially with the device main body gear,
A process cartridge detachable from an apparatus main body of an electrophotographic image forming apparatus that forms an image on a recording medium, comprising: an electrophotographic photosensitive drum; and a process unit acting on the electrophotographic photosensitive drum. A twisted cartridge projection that is provided at one end in the longitudinal direction of the electrophotographic photosensitive drum and that fits into the twisted recess; and a tip of the cartridge projection, which is provided substantially coaxially with the cartridge projection. When the process cartridge is mounted on the main body of the apparatus, the cartridge concave section having the main body convex portion penetrating into the cartridge concave portion when the process cartridge is mounted on the main body of the apparatus. When the main body gear rotates with the cartridge projection fitted in the main body concave portion, the main body concave portion and the cartridge are rotated. Via the projections, the process cartridge rotational force of the main body gear is characterized by being configured so as to be transmitted to said electrophotographic photosensitive drum. 2. The process cartridge according to claim 1, wherein an inner surface of the cartridge recess is inclined inward from a front end toward a back. 3. The process cartridge according to claim 1, wherein a hole penetrates a depth side of the cartridge concave portion. 4. The process cartridge according to claim 1, wherein when the main body convex portion enters the cartridge concave portion, there is play between the cartridge concave portion and the main body convex portion. 5. When the rotational driving force is transmitted to the electrophotographic photosensitive drum, the inner peripheral surface of the cartridge recess does not contact the outer peripheral surface of the main body projection. The process cartridge according to claim 4. 6. The process cartridge according to claim 1, wherein the shape of the cartridge projection is substantially a triangular prism. 7. The triangular prism is substantially a regular triangular prism.
7. The process cartridge according to claim 6, wherein a corner portion of the equilateral triangular prism has a chamfered shape. 8. A drum flange is provided at one end of the electrophotographic photosensitive drum, wherein the drum flange rotatably supports the electrophotographic photosensitive drum on a cartridge frame. 2. The process according to claim 1, wherein the shaft is provided with the cartridge protrusion and the cartridge recess at the end of the shaft, and the drum flange is a one-piece molded product made of plastic. cartridge. 9. The cartridge frame further includes a circular outer wall provided over the entire outer peripheral surface of the twisted projection, or an arc-shaped outer wall extending along a part of the outer peripheral surface of the twisted cartridge projection. 2. The process cartridge according to claim 1, wherein the outer wall engages with a concave portion provided on the apparatus main body when the process cartridge is mounted on the apparatus main body. 3. 10. When the process cartridge is mounted on the apparatus main body, and when the electrophotographic photosensitive drum is in a standby state in which a rotational driving force is not transmitted, the outer wall and the apparatus main body recess and / or the The process cartridge according to claim 9, wherein a part of an inner surface of the cartridge recess contacts a part of an outer peripheral surface of the main body protrusion. 11. The process cartridge according to claim 1, wherein when a rotational driving force is transmitted to the electrophotographic photosensitive drum, the cartridge projection receives a pull-in action force by the main body recess. 12. The electrophotographic photosensitive drum, wherein the process cartridge comprises: the electrophotographic photosensitive drum; and developing means for developing at least a latent image formed on the electrophotographic photosensitive drum as the process means. One of a charging unit for charging the photosensitive drum and a cleaning unit for removing toner remaining on the electrophotographic photosensitive drum is integrally unitized, and is detachable from the apparatus main body. The process cartridge according to claim 1, wherein 13. The device according to claim 3, further comprising an outwardly extending portion provided at a portion of the twisted surface of the main body concave portion that does not contact the cartridge projection.
The process cartridge according to 1. 14. The process cartridge according to claim 13, wherein the surface of the outwardly extending portion has a shape substantially along the outer periphery of a main body shaft provided with a main body concave portion. 15. The process cartridge according to claim 1, wherein an outer peripheral surface of the main body convex portion is inclined outward from a front end toward a back. 16. The twist amount of the cartridge projection is
2. The process cartridge according to claim 1, wherein a ratio of the rotation direction is about 1 to 15 degrees with respect to an axis length of about 1 mm. 17. The process cartridge according to claim 1, wherein a cross section of the main body recess is substantially triangular. 18. The process cartridge according to claim 17, wherein the triangle is a substantially equilateral triangle. 19. A motor, an apparatus body gear for receiving a driving force from the motor, and a body recess formed of a twisted surface and provided substantially coaxially with the apparatus body gear. Wherein the body recess is provided in the device body gear, at the tip of a cylindrical shaft provided coaxially with the device body gear, and the body recess is substantially triangular in cross section. And, among the twisted surfaces of the main body concave portion, a portion not in contact with the cartridge projection has a concave portion having an arc-shaped surface substantially along the outer periphery of the shaft, inside the main body concave portion, A main body convex portion provided substantially coaxially with the device main body gear,
A process cartridge detachable from an apparatus main body of an electrophotographic image forming apparatus that forms an image on a recording medium, comprising: an electrophotographic photosensitive drum; and a process unit acting on the electrophotographic photosensitive drum. A twisted cartridge projection that is provided at one longitudinal end of the electrophotographic photosensitive drum and that fits into the twisted recess; and wherein the cartridge projection is substantially triangular prism-shaped. A cartridge recess provided substantially coaxially with the cartridge projection; and the main body projection enters the cartridge recess when the process cartridge is mounted in the apparatus main body. A drum flange is provided at one end of the electrophotographic photosensitive drum, and a cart is provided on the drum flange. A shaft for rotatably supporting the electrophotographic photosensitive drum on a cartridge frame, and a cartridge projection and a cartridge recess provided at a tip of the shaft. When the cartridge is mounted on the apparatus main body and the main body gear rotates in a state where the cartridge projection is fitted into the main body recess, the rotational force of the main body gear is increased via the main body recess and the cartridge projection. A process cartridge configured to be transmitted to the electrophotographic photosensitive drum. 20. The process cartridge according to claim 19, wherein the inner surface of the cartridge recess is inclined inward from the front end toward the back. 21. The cartridge according to claim 19, wherein a hole extends through the inside of the concave portion of the cartridge.
0. The process cartridge according to 0. 22. The apparatus according to claim 19, wherein when the main body convex portion enters the cartridge concave portion, play exists between the cartridge concave portion and the main body convex portion.
The process cartridge according to 1. 23. The method according to claim 19, wherein when a rotational driving force is transmitted to the electrophotographic photosensitive drum, an inner peripheral surface of the cartridge concave portion does not contact an outer peripheral surface of the main body convex portion. The process cartridge according to claim 22. 24. The process cartridge according to claim 19, wherein the triangular prism is substantially a regular triangular prism, wherein a corner of the regular triangular prism has a chamfered shape. 25. Further, the cartridge frame is provided with a circular outer wall over the entire outer peripheral surface of the twisted projection, or an arc-shaped outer wall is formed along a part of the outer peripheral surface of the twisted cartridge projection. 20. The process cartridge according to claim 19, wherein, when the process cartridge is mounted on the apparatus main body, the outer wall is engaged with a concave portion provided on the apparatus main body. 26. When the process cartridge is mounted on the apparatus main body, and when the electrophotographic photosensitive drum is in a standby state in which rotational driving force is not transmitted, the outer wall and the apparatus main body concave portion and / or the 26. The process cartridge according to claim 25, wherein a part of an inner surface of the cartridge recess contacts a part of an outer peripheral surface of the main body projection. 27. The process cartridge according to claim 19, wherein when a rotational driving force is transmitted to the electrophotographic photosensitive drum, the cartridge projection receives a pull-in action force by the main body recess. 28. The process cartridge, comprising: the electrophotographic photosensitive drum; developing means for developing at least a latent image formed on the electrophotographic photosensitive drum as the process means; and the electrophotographic photosensitive drum. One of a charging unit for charging the photosensitive drum and a cleaning unit for removing toner remaining on the electrophotographic photosensitive drum is integrally unitized, and is detachable from the apparatus main body. 20. The process cartridge according to claim 19, wherein: 29. The process cartridge according to claim 19, wherein an outer peripheral surface of the main body convex portion is inclined outward from a front end side to a rear side. 30. The amount of twist of the cartridge projection is
20. The process cartridge according to claim 19, wherein the ratio of the rotation direction is about 1 to 15 degrees with respect to the axis length of about 1 mm. 31. The process cartridge according to claim 19, wherein the triangle is a substantially equilateral triangle. 32. A motor, a driving rotator for receiving a driving force from the motor, and a concave portion having a twisted non-circular cross section having an inner convex portion substantially coaxial with a rotation center axis of the driving rotator. A process cartridge having a twisted non-circular cross-sectional convex portion having an inner concave portion and detachable from an apparatus main body of an electrophotographic image forming apparatus for forming an image on a recording medium, comprising a rotatable electrophotographic photosensitive member. A process drum acting on the electrophotographic photosensitive drum; and a non-circular concave or convex portion provided coaxially with a rotation center axis at one longitudinal end of the electrophotographic photosensitive drum. A projection having a twisted non-circular cross section having an inner depression or a depression having an inner projection. The projection or the depression of the electrophotographic photosensitive drum is relatively rotated with respect to the driving rotating body. First possible rotation direction The paired position has a shape and dimensions that can take a second rotational direction relative position in which the two rotational center axes are substantially coaxial with each other and cannot rotate in one direction, and the inner convex portion of the twisted concave portion is twisted. A process cartridge wherein the first relative position in the rotational direction and the second relative position in the rotational direction can be taken in a state of entering the concave portion inside the convex portion. 33. The process cartridge according to claim 32, wherein the inner surface of the inner concave portion is inclined inward from the front end toward the back. 34. The process cartridge according to claim 32, wherein a hole penetrates a depth side of the inner concave portion. 35. The process cartridge according to claim 32, wherein when the inner convex portion enters the inner concave portion, a play exists between the inner concave portion and the inner convex portion. 36. An inner peripheral surface of the inner concave portion does not contact an outer peripheral surface of the inner convex portion when a rotational driving force is transmitted to the electrophotographic photosensitive drum. 36. The process cartridge according to claim 35. 37. The process cartridge according to claim 32, wherein the shape of the twisted convex portion is substantially a triangular prism. 38. The process cartridge according to claim 37, wherein the triangular prism is substantially a regular triangular prism, wherein a corner of the regular triangular prism has a chamfered shape. 39. A drum flange is provided at one end of the electrophotographic photosensitive drum, wherein the drum flange rotatably supports the electrophotographic photosensitive drum on a cartridge frame. 33. The shaft according to claim 32, wherein the twisted convex portion and the inner concave portion are provided at a tip of the shaft, and the drum flange is an integrally molded product made of plastic.
The process cartridge according to 1. 40. The cartridge frame is provided with a circular outer wall over the entire outer peripheral surface of the twisted cartridge convex portion, or an arc shape along a part of the outer peripheral surface of the twisted cartridge convex portion. 33. The process according to claim 32, wherein the outer wall engages with a concave portion provided in the apparatus main body when the process cartridge is mounted on the apparatus main body. cartridge. 41. When the process cartridge is mounted on the apparatus main body, and in a standby state in which a rotational driving force is not transmitted to the electrophotographic photosensitive drum, the outer wall and the apparatus main body concave portion and / or the 41. The process cartridge according to claim 40, wherein a portion of the inner surface of the inner concave portion contacts a portion of the outer peripheral surface of the inner convex portion. 42. The method according to claim 32, wherein when a rotational driving force is transmitted to the electrophotographic photosensitive drum, the twisted convex portion receives a pull-in action force by the twisted concave portion. Process cartridge. 43. The electrophotographic photosensitive drum, comprising: the electrophotographic photosensitive drum; and developing means for developing at least a latent image formed on the electrophotographic photosensitive drum as the processing means. One of a charging unit for charging the photosensitive drum and a cleaning unit for removing toner remaining on the electrophotographic photosensitive drum is integrally unitized, and is detachable from the apparatus main body. 33. The process cartridge according to claim 32, wherein: 44. The device according to claim 32, further comprising an outwardly extending portion provided in a portion of the twisted surface of the concave portion of the main body that does not contact the twisted convex portion. Process cartridge. 45. The process cartridge according to claim 44, wherein the surface of the outwardly extending portion has a shape substantially along the outer periphery of a main body shaft provided with a twisted concave portion. 46. The process cartridge according to claim 32, wherein the outer peripheral surface of the inner convex portion is inclined outward from the front end toward the rear. 47. The process according to claim 32, wherein the amount of twist of the twisted protrusion is about 1 to 15 degrees in the rotational direction with respect to about 1 mm of the axis length. cartridge. 48. The process cartridge according to claim 32, wherein the cross section of the twisted recess is substantially triangular. 49. The process cartridge according to claim 48, wherein said triangle is a substantially equilateral triangle. 50. A motor, a device body gear for receiving a driving force transmitted from the motor, and a cross-section provided at a substantially central portion of the device body gear and integrally rotating with the device body gear. Has a main body recess formed by a polygonal twisted surface, and a main body projection provided inside the main body recess, and is attached to and detached from an apparatus main body of an electrophotographic image forming apparatus for forming an image on a recording medium. A driving force transmitting component for transmitting a driving force to an electrophotographic photosensitive drum of a possible process cartridge and a developing roller for developing a latent image formed on the electrophotographic photosensitive drum, A gear for transmitting a driving force received from the apparatus main body to the developing roller when the process cartridge is mounted on the apparatus main body, a shaft provided at a central portion of the gear, and a process cartridge. When the cartridge is mounted on the apparatus main body, it is fitted with the hole provided in the apparatus main body, and a twisted cartridge projection provided at the tip of the shaft portion for receiving transmission of driving force from the apparatus main body. A cartridge recess provided in the projection, wherein the shaft receives a driving force received from the apparatus body via the body recess and the cartridge projection in a state where the main body projection has entered the cartridge recess. A driving force transmitting part for transmitting the driving force to the electrophotographic photosensitive drum through the helical gear and to the developing roller via the helical gear. 51. The driving force transmitting component according to claim 50, wherein the helical gear, the shaft portion, and the cartridge projection are integrally formed of resin. 52. A motor, an apparatus body gear for receiving a driving force from the motor, and a cross-section provided at a substantially central portion of the apparatus body gear and integrally rotating with the apparatus body gear. A main body recess formed of a polygonal twisted surface and a main body projection provided inside the main body recess,
An electrophotographic photosensitive drum used in a process cartridge detachable from an apparatus main body of an electrophotographic image forming apparatus for forming an image on a recording medium, comprising: a. A cylinder having a photosensitive layer on a peripheral surface; b. A gear for transmitting a driving force received from the apparatus main body to the developing roller when the process cartridge is mounted on the apparatus main body; a shaft provided at a central portion of the gear; and a process cartridge provided on the apparatus main body. A twisted cartridge projection provided at the end of the shaft portion for receiving transmission of driving force from the apparatus main body when fitted in the hole provided in the apparatus main body when mounted, and provided on the projection. And a driving force received from the apparatus main body via the main body concave portion and the cartridge protrusion in a state where the main body protrusion enters the cartridge concave portion through the shaft portion. A driving force transmitting component attached to one end of the cylinder, for transmitting the driving force to a body drum, and transmitting the driving force to the developing roller via the helical gear. An electrophotographic photosensitive drum characterized by the following. 53. The electrophotographic photosensitive drum according to claim 52, wherein the gear, the shaft, and the cartridge projection are integrally formed of resin, and the resin is polyacetal, polycarbonate, polyamide, or polybutylene terephthalate. 54. An electrophotographic image forming apparatus for detachably attaching a process cartridge and forming an image on a recording medium, comprising: (a) a motor; and (b) receiving a driving force from the motor. (C) a main body recess formed of a twisted surface and provided substantially coaxially with the main body gear; and (d) inside the main body recess, wherein the main body of the device is provided. (E) an electrophotographic photosensitive drum, a process unit acting on the electrophotographic photosensitive drum, and a longitudinal end of the electrophotographic photosensitive drum. A twisted cartridge projection that fits into the twisted recess provided; and a cartridge that is a distal end of the cartridge projection and is substantially coaxial with the cartridge projection. And a unit, wherein when the process cartridge is mounted on the apparatus main body, the main body convex portion enters the cartridge concave portion, and when the process cartridge is mounted on the apparatus main body, the cartridge When the main body gear is rotated in a state where the projection is fitted to the main body concave portion, the rotational force of the main body gear is transmitted to the electrophotographic photosensitive drum via the main body concave portion and the cartridge protrusion. And a cartridge mounting means for removably mounting the process cartridge. 55. An electrophotographic image forming apparatus for detachably attaching a process cartridge to form an image on a recording medium, comprising: (a) a motor; and (b) receiving a drive force from the motor. (C) a main body recess formed of a twisted surface provided substantially coaxially with the main body gear, wherein the main body recess is provided in the main body gear, Is provided at the tip of a cylindrical shaft provided coaxially with the gear, and the body recess is substantially triangular in cross section;
A portion of the twisted surface of the main body recess that does not contact the cartridge projection has a recess having an arc-shaped surface substantially along the outer periphery of the shaft. (D) Inside the main body recess A process cartridge detachable from an apparatus main body of an electrophotographic image forming apparatus for forming an image on a recording medium, the process cartridge comprising: the apparatus main body gear; and a main body projection provided substantially coaxially. (E) an electrophotographic photoreceptor drum, a process means acting on the electrophotographic photoreceptor drum, and a twisted fitting provided with the twisted recess provided at one longitudinal end of the electrophotographic photoreceptor drum. A cartridge projection, wherein the cartridge projection is substantially triangular prism-shaped; a tip of the cartridge projection, which is provided substantially coaxially with the cartridge projection. When the process cartridge is mounted on the apparatus main body, the main body convex portion enters the cartridge concave portion, and a drum flange is provided at one end of the electrophotographic photosensitive drum. And a shaft for rotatably supporting the electrophotographic photosensitive drum on a cartridge frame on the drum flange, and a cartridge projection and a cartridge recess provided at a tip of the shaft. When the process cartridge is mounted on the apparatus main body and the main body gear is rotated in a state where the cartridge protrusion is fitted into the main body concave portion, the main body concave portion and the cartridge protrusion are connected to each other. Process car configured to transmit the rotational force of the main body gear to the electrophotographic photosensitive drum via And cartridge mounting means for removably mounting the cartridge. 56. An electrophotographic image forming apparatus for detachably attaching a process cartridge and forming an image on a recording medium, comprising: (a) a motor; and (b) a drive for receiving a driving force from the motor. (C) a concave portion having a twisted non-circular cross section having an inner convex portion or a convex portion having a twisted non-circular cross section having an inner concave portion, which is substantially coaxial with the rotation center axis of the driving rotary member; d) a rotatable electrophotographic photosensitive drum, a process means acting on the electrophotographic photosensitive drum, and the non-circular shape provided at one longitudinal end of the electrophotographic photosensitive drum coaxially with a rotation center axis thereof. A concave portion having a twisted non-circular cross section having an inner concave portion or a concave portion having an inner convex portion, which can be fitted with the concave portion or the convex portion. , Relative rotation with the driving rotating body A possible first rotational direction relative position, having a shape and dimensions capable of taking a second rotational direction relative position in which the two rotational center axes are substantially coaxial and non-relative in one direction, and the twisted concave portion Mounting means for removably mounting a process cartridge capable of taking the first rotational direction relative position and the second rotational direction relative position in a state where the inner convex portion enters the inner concave portion of the twisted convex portion; An electrophotographic image forming apparatus comprising: