JP2001324909A - Electrophotographic image forming device, process cartridge and rotation transmitting member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve image quality by improving the rotational accuracy of a photoreceptor drum. SOLUTION: As for the driving constitution of the photoreceptor drum by a coupling, a projecting part 39c is provided in the center of a main-body-side coupling 39a, and a recessed part 37b is provided in the center of a cartridge- side photoreceptor drum flange 36, then the projecting part 39c is fit in the recessed part 37b, whereby a coupling recessed shaft 39b is aligned with the center of the photoreceptor drum. The projecting part 39c is provided in the shaft 39b and the recessed part 37b is provided in a cartridge-side coupling projecting part 37. There is no possibility that vibration is caused by the coupling action of the projecting part 37a with the recessed part 39a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process cartridge detachable from an electrophotographic image forming apparatus main body, a rotation transmitting member, and an electrophotographic image forming apparatus.
Here, the electrophotographic image forming apparatus forms an image on a recording medium using an electrophotographic image forming method. Examples of the electrophotographic image forming apparatus include, for example, an electrophotographic copying machine, an electrophotographic printer (for example, a laser beam printer, an LED printer, and the like), a facsimile machine, a word processor, and the like.

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

[0003]

Any of the techniques described in the gazettes described in the description of the prior art below is 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 below.

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

Another object of the present invention is to provide an electrophotographic image forming apparatus, a process cartridge, and a rotation transmitting member which can further suppress the vibration of the process cartridge.

[0006]

The main present invention will be described below. The main invention numbers correspond to the claim numbers.

According to a first aspect of the present invention, there is provided a motor, an apparatus main body side gear rotatably driven by the motor, a main body positioning member, a protruding portion extending in a rotation center axis direction of the gear, and the protruding portion. A process cartridge having a connection hole provided on the rotation center axis of the unit and a projection provided at the bottom of the connection hole, the process cartridge being detachable from a photographic image forming apparatus main body; A process unit that acts on the photoconductor drum, a connection protrusion in contact with the connection hole, the connection protrusion provided at a longitudinal end of the electrophotographic photoconductor drum, and a process cartridge provided on the apparatus main body. When connecting the connection hole and the connection projection by being mounted on the mounted cartridge mounting portion, the connection hole may have a contact portion that aligns with the projection provided at the bottom of the connection hole. A process cartridge according to claim.

According to a fourteenth aspect of the present invention, there is provided: a, a motor, an apparatus body side gear driven and rotated by the motor, a body positioning member, and a protruding portion extending in a rotation center axis direction of the gear. A connection hole provided on the rotation center axis of the protrusion, and a protrusion provided at the bottom of the connection hole,
B, a process cartridge detachable from the electrophotographic image forming apparatus main body, comprising: an electrophotographic photosensitive drum; process means acting on the electrophotographic photosensitive drum; A connection protrusion provided in contact with the hole, the connection protrusion being provided at a longitudinal end of the electrophotographic photosensitive drum, and a process cartridge being mounted on a cartridge mounting portion provided in the apparatus main body. A rotation transmitting member provided between a process cartridge that receives a rotational driving force from the apparatus main body by connecting a connection protrusion, the rotation transmission member having the connection hole and the connection protrusion, and a protrusion at the bottom of the connection hole. A rotation transmitting member, characterized in that the connecting projection has a contact portion that is aligned with the contact portion and is aligned.

According to a twenty-fourth aspect of the present invention, there is provided an electrophotographic image forming apparatus for detachably attaching a process cartridge to form an image on a recording medium, comprising: a, a motor; A gear; c, a main body positioning member; d, a protrusion extending in the rotation center axis direction of the gear; e, a connection hole provided on the rotation center axis of the protrusion, and a connection hole provided at the bottom of the connection hole. F, an electrophotographic photosensitive drum, a process means acting on the electrophotographic photosensitive drum, and a connecting projection in contact with the connection hole, the connecting projection being in a longitudinal direction of the electrophotographic photosensitive drum. A connection protrusion provided at an end portion, and a process cartridge is provided at a bottom of the connection hole when the process cartridge is mounted on a cartridge mounting portion provided on the apparatus main body and the connection hole is connected to the connection protrusion. Comprising: a mounting means for removably mounting a process cartridge having a contact portion which is aligned with a contacted convex portion, and a conveying means for conveying the recording medium. It is a photographic image forming apparatus.

[0010]

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 means using toner to form a toner image. Thereafter, the toner image formed on the electrophotographic photosensitive member is transferred to a recording medium by a transfer unit to form an image.

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

In such a process cartridge, in order to drive at least the electrophotographic photosensitive drum, when the process cartridge is mounted on the image forming apparatus main body,
A power transmission member connected to a drive source of the image forming apparatus main body and the electrophotographic photosensitive drum are connected.

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

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

[0016]

(Embodiment 1) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Next, a preferred embodiment of the present invention will be described. In the following description, the process cartridge B
The short direction means that the process cartridge B is
4, which is the same as the direction in which the recording medium is conveyed. The longitudinal direction of the process cartridge B is
This is a direction intersecting (substantially perpendicular to) the direction in which the process cartridge B is attached to and detached from the apparatus main body 14, a direction parallel to the surface of the recording medium, and intersecting (substantially perpendicular to) the conveying direction of the recording medium. . Further, the left and right of the process cartridge are right or left when the recording medium is viewed from above according to the transport direction of the recording medium.

FIG. 1 is an explanatory diagram of a configuration of an electrophotographic image forming apparatus (laser beam printer) to which an embodiment of the present invention is applied, and FIG. 2 is an external perspective view thereof. 3 to 8 are drawings relating to a process cartridge to which the embodiment of the present invention is applied. 3 is a side sectional view of the process cartridge, FIG. 4 is an external perspective view schematically showing the external appearance, FIG. 5 is a right side view thereof, FIG. 6 is a left side view thereof, and FIG. FIG. 8 is a perspective view when the process cartridge is turned over and viewed from above. Further, in the following description, the upper surface of the process cartridge B is a surface located above when the process cartridge B is mounted on the apparatus main body 14, and the lower surface is a surface located below.

(Electrophotographic Image Forming Apparatus A and Process Cartridge B) First, a laser beam printer A as an electrophotographic image forming apparatus to which an embodiment of the present invention is applied will be described with reference to FIGS. FIG. 3 is a side sectional view of the process cartridge B.

As shown in FIG. 1, the laser beam printer A forms an image on a recording medium (for example, recording paper, OHP sheet, cloth, etc.) by an electrophotographic image forming process. Then, a toner image is formed on a drum-shaped electrophotographic photosensitive member (hereinafter, referred to as a photosensitive drum).
More specifically, the photoconductor drum is charged by a charging unit, and then the photoconductor drum is irradiated with laser light corresponding to image information from the optical unit to form a latent image corresponding to the image information on the photoconductor drum. Then, the latent image is developed by a developing unit to form a toner image. Then, in synchronization with the formation of the toner image, the recording medium 2 set in the sheet feeding cassette 3a is picked up by the pickup roller 3b and the conveying roller pair 3
It is reversed and conveyed by c, 3d and a pair of registration rollers 3e. Next, the toner image formed on the photosensitive drum 7 of the process cartridge B is transferred to the recording medium 2 by applying a voltage to a transfer roller 4 as a transfer unit. Thereafter, the recording medium 2 to which the toner image has been transferred is conveyed to the fixing unit 5 by the conveyance guide 3f. The fixing unit 5 includes a driving roller 5c and a fixing roller 5 including a heater 5a.
b. Then, heat and pressure are applied to the passing recording medium 2 to fix the transferred toner image. Then, the recording medium 2 is conveyed by a pair of discharge rollers 3g, 3h, and 3i, and is discharged to a discharge tray 6 through a reversing path 3j. The discharge tray 6 is provided on the upper surface of the apparatus main body 14 of the image forming apparatus A. It is also possible to operate the swingable flapper 3k and discharge the recording medium 2 by the discharge roller pair 3m without passing through the reversing path 3j. In the present embodiment, the pickup roller 3b, the transport roller pair 3c, 3d, the registration roller pair 3e, the transport guide 3
f, discharge roller pair 3g, 3h, 3i and discharge roller pair 3
The transport means 3 is constituted by m.

On the other hand, the process cartridge B rotates a photosensitive drum 7 having a photosensitive layer 7e (see FIG. 11) as shown in FIGS. Is uniformly charged by the application of the voltage. Next, a laser beam corresponding to the image information from the optical system 1 is applied to the photosensitive drum 7 through the exposure opening 1e to form a latent image. Then, the latent image is developed by developing means 9 using toner. That is, the charging roller 8
Is provided in contact with the photosensitive drum 7 and charges the photosensitive drum 7. The charging roller 8 is driven and rotated by the photosensitive drum 7. The developing unit 9 supplies toner to a developing area of the photoconductor drum 7 to develop a latent image formed on the photoconductor drum 7. The optical system 1 includes a laser diode 1a, a polygon mirror 1b, a lens 1
c, a reflection mirror 1d.

Here, the developing means 9 includes the toner container 1
The toner in 1A is rotated by rotation of the toner feeding member 9b.
The toner is sent to the developing roller 9c through the toner supply opening 11i. Then, while rotating the developing roller 9c incorporating the fixed magnet, a toner layer provided with a triboelectric charge by the developing blade 9d is formed on the surface of the developing roller 9c.
The toner is supplied to a developing area of the photosensitive drum 7. Then, the toner image is transferred to the photosensitive drum 7 in accordance with the latent image, thereby forming a toner image and visualizing the toner image. Here, the developing blade 9d regulates the amount of toner on the peripheral surface of the developing roller 9c and applies a triboelectric charge. A toner stirring member 9e for circulating toner in the developing chamber is rotatably mounted near the developing roller 9c.

Then, a voltage having a polarity opposite to that of the toner image is applied to the transfer roller 4 to transfer the toner image formed on the photosensitive drum 7 to the recording medium 2.
By 0, the residual toner on the photosensitive drum 7 is removed.
Here, the cleaning means 10 scrapes off the toner remaining on the photoconductor drum 7 by an elastic cleaning blade 10a provided in contact with the photoconductor drum 7 and collects it in the waste toner reservoir 10b.

In the process cartridge B, a toner frame 11 having a toner container (toner storage section) 11A for storing toner and a developing frame 12 for holding developing means 9 such as a developing roller 9c are connected. A cleaning means 10 such as a photosensitive drum 7, a cleaning blade 10a, and the like, and a cleaning frame 13 to which a charging roller 8 is attached are combined with the photosensitive drum 7. The process cartridge B is moved by the operator to the image forming apparatus main body 14.
It is removable.

The process cartridge B is provided with an exposure opening 1e for irradiating the photosensitive drum 7 with light corresponding to image information and a transfer opening 13n for facing the photosensitive drum 7 to the recording medium 2. is there. More specifically, the exposure opening 1e is provided in the cleaning frame 13, and the transfer opening 13n is formed between the developing frame 12 and the cleaning frame 13.

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

The process cartridge B according to the present embodiment has a housing in which a toner frame 11 and a developing frame 12 are connected and a cleaning frame 13 is rotatably connected thereto. A cartridge is formed by accommodating the drum 7, the charging roller 8, the developing means 9, the cleaning means 10, and the like. Then, the process cartridge B is detachably mounted on a cartridge mounting means provided on the image forming apparatus main body 14.

(Structure of Housing of Process Cartridge B) The process cartridge B according to this embodiment is
As described above, the housing is formed by combining the toner frame 11, the developing frame 12, and the cleaning frame 13. Next, the structure will be described.

As shown in FIG. 3, a toner feeding member 9b is rotatably attached to the toner frame 11. A developing roller 9c and a developing blade 9d are mounted on the developing frame 12, and a stirring member 9e for circulating toner in the developing chamber is rotatably mounted near the developing roller 9c. As shown in FIG. 3, the developing frame 12 faces the longitudinal direction of the developing roller 9c.
An antenna rod 9h is attached substantially parallel to c. Then, the toner frame 11 and the developing frame 12 are welded (in this embodiment, ultrasonic welding JP) to form a developing unit D (see FIG. 13) as an integrated second frame.

When the process cartridge B is detached from the image forming apparatus main body 14, the drum shutter member 18 for covering the photosensitive drum 7 and protecting the photosensitive drum 7 from exposure to light for a long time or contact with foreign matter is used as a toner developing unit. Attached to.

As shown in FIG. 6, the drum shutter member 18 has a shutter cover 18a for opening and closing the transfer opening 13n shown in FIG. 3, and links 18b and 18c for supporting the shutter cover 18a. At both ends in the longitudinal direction of the shutter cover 18a and on the upstream side in the transport direction of the recording medium 2, one end of a right link 18c is pivotally attached to a hole 40g of the developing holder 40 as shown in FIGS. As shown in FIGS. 6 and 7, one end of the left link 18c is pivotally attached to a boss 11h provided on the lower frame 11b of the toner frame 11. The other ends of the links 18c on both sides are pivotally mounted on the upstream side with respect to the mounting direction of the process cartridge B of the shutter cover 18a. The link 18c is a metal wire, and a portion pivotally connected to the shutter cover 18a is connected between both sides of the process cartridge B, and the left and right links 18c are integrated. The link 18b is provided only on one side of the shutter cover 18a. One end of the link 18b is pivotally attached to the shutter cover 18a at the downstream end in the transport direction of the recording medium 2 from the position where the link 18c is pivotally connected, and the other end is developed. It is pivotally attached to a dowel 12 d provided on the frame 12. This link 18b is a synthetic resin.

The links 18b and 18c have different lengths, and form a four-bar linkage mechanism in which the shutter cover 18a and the frame including the toner frame 11 and the developing frame 12 are linked. The side projections 18c1 provided on the links 18c on both sides come into contact with a fixed member (not shown) provided near the cartridge mounting space S of the image forming apparatus 14,
The movement of the process cartridge B operates the drum shutter member 18 to open the shutter cover 18a.

This shutter cover 18a, link 18
b, 18c, the drum shutter member 18
The shutter cover 18a is biased so as to cover the transfer opening 13n by a not-shown torsion coil spring inserted into 2d and locked at one end by a link 18b and at the other end by the developing frame 12.

As shown in FIGS. 3 and 12, the photosensitive frame 7, the charging roller 8 and the cleaning means 10 are attached to the cleaning frame 13 to form a cleaning unit C (FIG. 12) as a first frame. Reference).

Then, the developing unit D and the cleaning unit C are rotatably connected to each other by a connecting member 22 having a round pin, thereby forming a process cartridge B. That is, as shown in FIG. 13, a circular turning hole 20 is provided at the tip of an arm portion 19 formed on both sides in the longitudinal direction (axial direction of the developing roller 9c) of the developing frame 12 in parallel with the developing roller 9c. (See FIG. 13).
On the other hand, concave portions 21 for entering the arm portions 19 are provided at two positions on both sides in the longitudinal direction of the cleaning frame 13 (see FIG. 12). The arm 19 is inserted into the recess 21, the coupling member 22 is pressed into the mounting hole 13 e outside the cleaning frame 13, and the rotation hole 2 at the end of the arm 19 is inserted.
Of the developing unit D and the cleaning unit C
Are rotatably coupled about the coupling member 22. Here, the outer mounting hole 13e is provided in the side plate 13s of the cleaning frame 13, and the inner mounting hole 13e is provided in the partition wall 13t inside the cleaning frame 13. At this time, a compression coil spring 22a inserted and attached to a dowel (not shown) standing upright at the base of the arm portion 19 hits the upper wall of the concave portion 21 of the cleaning frame 13, and the developing frame 12 is moved downward by the compression coil spring 22a. By urging, the developing roller 9c is reliably pressed against the photosensitive drum 7. The upper wall of the concave portion 21 of the cleaning frame 13 is inclined so that the compression coil spring 22a gradually increases the compression from the non-compression state when the developing unit D and the cleaning unit C are assembled. Therefore, as shown in FIG. 13, by attaching spacer rollers 9i having a diameter larger than that of the developing roller 9c to both ends in the longitudinal direction of the developing roller 9c, the rollers 9i are pressed against the photosensitive drum 7, and the photosensitive drum 7 and the developing roller 9c oppose each other at a constant interval (about 300 μm). Therefore,
The developing unit D and the cleaning unit C are connected to the connecting member 2.
2 can rotate around each other, and the elastic force of the compression coil spring 22a can maintain the positional relationship between the peripheral surface of the photosensitive drum 7 and the peripheral surface of the developing roller 9c.

As described above, since the compression coil spring 22a is attached to the developing frame 12 at the root side of the arm portion 19, the pressing force of the compression coil spring 22a does not reach the portion other than the root of the arm portion 19, and the developing frame 12 is Even if the circumference of the spring seat is not particularly strengthened so that the attached member is used as a spring seat, the root side of the arm portion 19 is a portion having high strength and rigidity, which is effective in maintaining accuracy.

(Structure of Guide Means for Process Cartridge B) Next, guide means for attaching and detaching the process cartridge B to and from the apparatus main body 14 will be described. This guide means is shown in FIGS. FIG. 9 is a left perspective view when the process cartridge B is viewed in a direction (arrow X) in which the process cartridge B is mounted on the apparatus main body 14 (when viewed from the developing unit D side). FIG. 10 is a perspective view of the right side.

As shown in FIGS. 4, 5, 6, and 7, guide means serving as guides for attaching and detaching the process cartridge B to and from the apparatus main body 14 are provided on both outer surfaces of the cleaning frame 13. Is provided. The guide means includes a cylindrical guide 13aR as a positioning guide member,
13aL and detent guides 13bR and 13bL as guide members serving as attitude holding means at the time of attachment / detachment.

As shown in FIG. 5, the cylindrical guide 13a
R is a hollow cylindrical member, and a detent guide 13bR
Is formed integrally with the cylindrical guide 13aR, and projects almost radially integrally from the circumference of the cylindrical guide 13aR. The mounting flange 13a is attached to the cylindrical guide 13aR.
R1 is provided integrally. Thus, the cylindrical guide 13aR, the detent guide 13bR, the mounting flange 13
The right guide member 13R having aR1 is the mounting flange 1
The small screw 13aR2 is screwed and fixed to the cleaning frame 13 through the small screw hole 3aR1. The detent guide 13bR of the right guide member 13R fixed to the cleaning frame 13 is disposed on the side of the developing frame 12 so as to extend to the side of the developing holder 40 fixed to the developing frame 12. I have.

As shown in FIG. 6, a hole 13k1 (see FIG. 11) of the cleaning frame 13 has an enlarged diameter portion 7a of the drum shaft 7a.
2 are fitted. Then, it is fitted to a positioning pin 13c protruding from the side surface of the cleaning frame 13 and is stopped from rotating. The flat flange 29 fixed to the cleaning frame 13 with small screws 13d is directed outward (perpendicular to the plane of FIG. 6). The cylindrical guide 13aL protrudes toward the front side. The fixed drum shaft 7a rotatably supports the spur gear 7n fitted on the photosensitive drum 7 inside the flange 29 (see FIG. 11). The cylindrical guide 13aL and the drum shaft 7a are coaxial. The flange 29, the cylindrical guide 13aL, and the drum shaft 7a
Is integrally or integrally made of a metal material, for example, an iron material.

As shown in FIG. 6, the cylindrical guide 13aL
The rotation preventing guide 13bL, which is slightly apart from the cylindrical guide 13aL in the radial direction of the cylindrical guide 13aL,
Are formed integrally with the cleaning frame 13 so as to protrude to the side of the cleaning frame 13. The flange 29 is cut off at a portion where the detent guide 13bL interferes with the flange 29. The protrusion height of the rotation preventing guide 13bL to the side is such that the top surface substantially coincides with the top surface of the cylindrical guide 13aL. The detent guide 13bL extends to the side of the developing roller bearing box 9v fixed to the developing frame 12. As described above, the left guide member 13L includes a metal cylindrical guide 13aL and a synthetic resin detent guide 13bL.
Are provided separately from each other.

Next, the upper surface 13i of the cleaning unit C
Will be described. Here, the upper surface is a surface located above when the process cartridge B is mounted on the image forming apparatus main body 14.

In this embodiment, as shown in FIGS. 4 to 7, the right and left ends 13p and 13q of the upper surface 13i of the cleaning unit C in a direction orthogonal to the mounting direction of the process cartridge are respectively regulated. A contact portion 13j is provided. The regulation contact portion 13j defines the position of the process cartridge B when the process cartridge B is mounted on the image forming apparatus main body 14. That is, when the process cartridge B is mounted on the image forming apparatus main body 14, the regulating contact portion 13 j is attached to a fixed member 25 (see FIGS. 9 and 10) provided on the image forming apparatus main body 14.
Abuts on the process cartridge B and the cylindrical guide 1
Rotational positions around 3aR and 13aL are defined.

Next, the guide means on the image forming apparatus main body 14 side will be described. Opening / closing member 35 of image forming apparatus main body 14
1 is rotated counterclockwise in FIG. 1 around the fulcrum 35a, the upper part of the image forming apparatus main body 14 is opened, and the mounting portion of the process cartridge B looks like FIG. 9 and FIG. As shown in FIG. 9 on the left side and FIG. 10 on the right side, guide members 16R and 16L are respectively provided on the left and right inner walls of the image forming apparatus main body 14 from the opening where the opening / closing member 35 is opened, as shown in FIG. Is provided.

As shown in the figure, the guide members 16R, 16L
The guide portions 16a and 1 are obliquely provided so as to descend forward as viewed from the arrow X in the insertion direction of the process cartridge B.
6c and the cylindrical guides 13aR, 13a of the process cartridge B connected to the guide portions 16a, 16c, respectively.
It has semicircular positioning grooves 16b and 16d into which L just fits. The peripheral walls of the positioning grooves 16b and 16d have a cylindrical shape. The centers of the positioning grooves 16b and 16d are at the center of the cylindrical guides 13aR and 13aL of the process cartridge B when the process cartridge B is mounted on the apparatus main body 14.
Therefore, it also coincides with the center line of the photosensitive drum 7.

The width of each of the guide portions 16a and 16c is such that the cylindrical guide 13a is viewed from the mounting / dismounting direction of the process cartridge B.
R and 13aL have a width for loose fitting. Cylindrical guide 13
Although the detent guides 13bR and 13bL each having a narrower width than the diameters of the aR and 13aL fit loosely, the cylindrical guides 13aR and 13aL and the detent guide 13 naturally fit loosely.
The rotation of bR and 13bL is restricted by the guide portions 16a and 16c, and the process cartridge B is mounted while maintaining a certain range of posture. When the process cartridge B is mounted on the image forming apparatus main body 14, the cylindrical guides 13aR and 13aL of the process cartridge B are provided.
Are the positioning grooves 16b of the guide members 13R and 13L, respectively.
16 d and the right and left regulating contact portions 13 j of the cleaning frame 13 of the process cartridge B contact the fixed member 25 of the apparatus main body 14.

In the above-described process cartridge B, if the center lines connecting the centers of the cylindrical guides 13aR and 13aL at the cleaning unit C side and the developing unit D side are kept horizontal, the developing unit D side is higher than the cleaning unit C side. The weight distribution is such that a large first moment is generated.

To attach the process cartridge B to the image forming apparatus main body 14, the respective ribs 11c on the concave side 17 and the lower side of the toner frame 11 are gripped with one hand, and the cylindrical guides 13aR and 13aL are respectively held by the image forming apparatus. The detents 13bR and 13bL are inserted into the guides 16a and 16c of the cartridge mounting portion of the main body 14 and then the process cartridge B is lowered forward as viewed from the insertion direction, and the detent guides 13bR and 13bL are inserted into the guides 16a and 16c of the image forming apparatus main body 14. insert. Cylindrical guides 13aR, 13a of process cartridge B
L, the detent guides 13bR, 13bL advance to the back side along the guides 16a, 16c of the image forming apparatus main body 14, and the cylindrical guides 13aR, 13b of the process cartridge B.
13aL is a positioning groove 16b of the image forming apparatus main body 14,
16d, the cylindrical guides 13aR, 13a
L is seated at the positions of the positioning grooves 16b and 16d by the gravity of the process cartridge B. Thus, the positions of the cylindrical guides 13aR and 13aL of the process cartridge B are accurately determined with respect to the positioning grooves 16b and 16d. Since the center line connecting the centers of the cylindrical guides 13aR and 13aL is the center line of the photosensitive drum 7, the position of the photosensitive drum 7 is accurately determined in the image forming apparatus main body 14.

In this state, the fixing member 25 of the image forming apparatus main body 14 and the regulating contact portion 13 of the process cartridge B are
j has a slight gap. When the hand holding the process cartridge B is released, the process cartridge B descends around the cylindrical guides 13aR and 13aL, the cleaning unit C rises, and the regulating contact portion of the process cartridge B rises. Reference numeral 13j contacts the fixed member 25 of the image forming apparatus main body 14, and the process cartridge B is accurately mounted on the image forming apparatus main body 14. Thereafter, the opening / closing member 35 is connected to the fulcrum 3 in FIG.
Rotate clockwise around 5a and close.

The removal of the process cartridge B from the apparatus main body 14 is the reverse of the above, and the opening and closing member 35 of the apparatus main body 14 is opened, and the upper and lower ribs 11c forming the handle portion of the process cartridge B are put on the hands and lifted. Then, the cylindrical guides 13aR, 13aR,
13aL rotates about the positioning grooves 16b and 16d of the apparatus main body 14, and the regulating contact portion 1 of the process cartridge B is rotated.
3j is separated from the fixing member 25 of the apparatus main body 14. When the process cartridge B is further pulled, the cylindrical guide 13a
R, 13aL escape from the positioning grooves 16b, 16d and guide members 16R, 16L fixed to the apparatus main body 14.
When the process cartridge B is lifted as it is, the cylindrical guides 13aR and 13aL and the detent guides 13bR and 13bL of the process cartridge B are moved to the guide portions 16a and 16b of the apparatus body 14.
The process cartridge 16 moves up and moves upward, whereby the attitude of the process cartridge B is regulated, and the process cartridge B is taken out of the apparatus main body 14 without hitting other parts of the apparatus main body 14.

As shown in FIG. 12, the spur gear 7n
Is provided at the end of the photosensitive drum 7 opposite to the helical drum gear 7b in the axial direction. This spur gear 7n is
When the process cartridge B is mounted on the apparatus main body 14, the driving force for rotating the transfer roller 4 by engaging with a gear (not shown) coaxial with the transfer roller 4 provided on the apparatus main body 14 is provided. To communicate from.

(Toner Frame) The toner frame will be described in detail with reference to FIGS. 3, 5, and 7. FIG.

As shown in FIG. 3, the toner frame 11 is composed of two parts, an upper frame 11a and a lower frame 11b. The upper frame 11a bulges upward so as to occupy the space to the right of the optical system 1 of the image forming apparatus main body 14 as shown in FIG. The amount of toner in the cartridge B is increased. As shown in FIGS. 3, 4, and 7, a concave portion 17 is provided at the center in the longitudinal direction of the upper frame 11a from the outside, and has a function of a handle. Therefore, the operator holds the concave portion 17 of the upper frame 11a and the lower frame 1 by hand.
Hold the lower side of 1b and hold it. The longitudinal ribs 11c provided on one side of the recess 17 and below the lower frame 11b are non-slip when the process cartridge B is held. Then, as shown in FIG. 3, the flange 11a1 of the upper frame 11a is fitted to the flange 11b1 of the lower frame 11b having a peripheral edge, and is fitted to the welding surface U, and the welding ribs are melted by ultrasonic welding to thereby form the two frames. Body 11a, 11b
Is integrated. However, the joining method is not limited to ultrasonic welding, and may be, for example, heat welding, forced vibration, or bonding. When the two frames 11a and 11b are ultrasonically welded, the two frames 11a and 11b are
In addition to supporting the flanges 11a and 11b, a step 11m is provided on the upper surface outside the opening 11i and on the same plane as the flange 11b1.

As shown in FIG. 3, the toner frame 11
The slope K of the lower frame body 11b naturally falls when toner is consumed, that is, the slope K of the process cartridge B mounted on the apparatus main body 14 with the apparatus main body 14 being horizontal and the horizontal line. The angle θ with Z is about 65
Degree is preferred. In addition, the lower frame 11b is recessed downward so as to escape the rotation area of the toner feeding member 9b.
g. The rotation diameter of the toner feeding member 9b is 37
mm. The concave portion 11g may be recessed from the extension of the slope K by about 0 mm to 10 mm. This is because if the concave portion 11g is located above the slope K, the toner that has naturally fallen from above the slope K will not be fed into the developing frame 12 due to the toner between the concave portion 11g and the slope K. Is expected to remain, but in the present embodiment, the toner can be reliably sent from the toner frame 11 to the developing frame 12.

As described above, by providing the concave portion 11g as a relief for the toner feeding member 9b on the bottom surface of the toner frame 11, stable toner feeding performance can be obtained without increasing the cost.

When the process cartridge B is mounted on the main body 14 of the image forming apparatus, as described later, the shaft coupling member on the cartridge side and the shaft coupling member on the main body side are connected in conjunction with the closing operation of the opening / closing member 35. The photosensitive drum 7 and the like are rotatable by being driven by the apparatus main body 14.

{Coupling and Driving Configuration} Next, the configuration of a shaft coupling device which is a driving force transmission mechanism for transmitting a driving force from the image forming apparatus main body 14 to the process cartridge B will be described.

FIG. 14 shows a drum flange 36 as a driving force transmitting part in which a coupling convex shaft 37 is integrally formed.
15 is a partially cutaway perspective view of the photosensitive drum 7 to which the drum flange 36 is attached. FIG. 11 is a cross-sectional view showing a state where the photosensitive drum 7 shown in FIG. FIG. 16 is an enlarged perspective view of the vicinity of the coupling convex shaft 37 of the process cartridge B shown in FIG. 11, and FIG. 17 is a coupling convex shaft 37 (provided on the process cartridge B) as a shaft coupling member.
FIG. 4 is an explanatory diagram showing the relationship between a shaft and a concave shaft 39b (provided on the apparatus main body 14).

Now, as shown in FIGS. 15 to 17, the photosensitive drum 7 attached to the process cartridge B
A cartridge-side shaft coupling member is provided at one end in the longitudinal direction. The shaft coupling member has a coupling flange 3 attached to a drum flange 36 fixed to one end of the photosensitive drum 7.
7 (cylindrical shape), and a convex portion 37 a is formed on the distal end surface of the convex shaft 37. The projection 37a serves as one driven side connection projection of the shaft coupling member. In addition, the convex part 3
The end face of 7 a is parallel to the end face of the convex shaft 37. The convex shaft 37 is rotatably and axially movably fitted to a bearing 38 (see FIG. 11), and functions as a photosensitive drum rotating shaft. In the present embodiment, the drum flange 3
6, the coupling convex shaft 37 and the convex portion 37a are provided integrally. A helical drum gear 7b is provided integrally with the drum flange 36 in order to transmit a driving force to the developing roller 9c inside the process cartridge B. Therefore, as shown in FIG. 14, the drum flange 36 is an integrally molded product having the helical drum gear 7b, the convex shaft 37, and the convex portion 37a, and is a driving force transmitting component having a function of transmitting driving force. is there.

The convex portion 37a has a concave portion 37b at the center of the tip of the convex portion, a plurality of ribs 37c provided on the outer periphery of the convex portion 37, and a detailed shape of three ribs 37c.
Has a shape gradually twisted in the rotational direction in the axial direction. The concave portion 37b has its center on the rotation center line of the photosensitive drum 7 and is provided in the axial direction. In this example, the concave portion 37b is cylindrical. In this example, the ribs 37c are provided at three equal intervals in the circumferential direction.

A concave portion 39 fitted with the convex portion 37a.
a is a hole whose cross section is gradually twisted in the rotation direction in the polygonal axial direction. The recess 39a is a connection hole into which the projection 37a serving as the connection protrusion enters. The recess 39a
Has a substantially equilateral triangle in cross section. There is a convex portion 39d at the center of the bottom surface of the concave portion. The concave portion 39a rotates integrally with the large gear 43 (see FIG. 18) provided on the apparatus main body 14. Therefore, in the configuration of the present embodiment, the process cartridge B is mounted on the apparatus main body 14, and the convex portion 37a and the concave portion 39a provided on the apparatus main body 14 are fitted to each other, so that the rotational force of the concave portion 39a is increased. When transmitted to the portion 37a, each ridge line 37a1 of the outermost portion of the three ribs 37c and the inner surface 39a1, which is the peripheral wall of the concave portion 39a, abut equally (see FIG. 24B). When the center X1 of the coupling convex portion 37a and the center X2 of the concave portion 39a do not coincide with each other, as shown in FIG.
Only the ridge line c is pushed by one inner surface 39a1 of the concave portion 39a, and a force is applied so that the center X1 of the convex portion coincides with the center X2 of the concave portion so that the centers X1 and X2 coincide as shown in FIG. Aligned to. Further, a force acts in a direction in which the concave portion 39a draws the convex portion 37a due to the twist shape, and the convex end surface 37a2 comes into contact with the concave bottom surface 39a2. At this time, the concave portion 37b at the center of the convex portion front end and the convex portion 39d at the central portion of the concave bottom surface are fitted by the concave portion 39d by the pulling force of the convex portion 37a, and their axes are aligned. That is, the concave portion 37 b is provided on the center line of the photosensitive drum 7 and the convex portion 3
9d is provided on the rotation center line of the coupling concave shaft 39b, and the concave portion 37b and the convex portion 39d are cylindrical. In addition. The height of the projection 39d is shorter than the depth of the coupling recess 39a.

Then, as described above, there is a gap in the radial direction, and the convex portion 37a and the concave portion 39a which are easy to fit are fitted first, rotated and aligned, and the concave portion of the convex portion 37a is aligned. 37b and the concave portion 3 in the axial direction from the bottom surface 39a2 of the concave portion 39b.
7b is fitted into the concave portion 37b, so that the coupling convex portion 37a and the concave portion 3d are aligned during alignment.
9a, the coupling convex shaft 37 and the coupling concave shaft 39b are more accurately used when a lateral force acts in the radial direction.
Axis can be matched.

Therefore, the axial position and the center position of the photosensitive drum 7 integrated with the convex portion 37a in the image forming apparatus main body 14 are stably determined.

In this embodiment, when viewed from the photosensitive drum 7 side, the rotation direction of the photosensitive drum 7 is
The torsional directions of the three ribs 37c of the convex portion 37a are opposite directions from the root of the convex portion 37a toward the tip, and the torsional directions of the concave portions 39a are opposite directions from the entrance of the concave portion 39a toward the inside. The torsion direction of the helical drum gear 7b of the drum flange 36 is opposite to the torsion direction of the projection 37a.

As shown in FIG. 24, the coupling convex portion 37a and the concave portion 39a are formed such that the diameter of the circumscribed circle R0 of the three ribs 37c as the convex portion 37a = d0 and the cross section of the concave portion 39a are triangular. When the diameter of the inscribed circle R1 of the space is d1 and the diameter of the circumscribed circle R2 is d2, d1
<D0 <d2.

Specifically, a preferred example of the numerical range is as follows: d0 = about 3 mm to 70 mm, d1 = about 3 mm to 70 mm
mm and d2 = about 3 mm to about 70 mm.
Then, a size that satisfies the above-described relationship may be appropriately selected from this numerical range. In this embodiment, d0 = about 16 mm, d1 = about 9.5 mm, and
d2 was set to about 17.5 mm. The amount of twist of the convex portion 37a and the concave portion 39a is large enough to move the photosensitive drum 7 or the process cartridge B in the longitudinal direction when the convex portion 37a and the concave portion 39a are rotating. In the example of the embodiment, the angle of the twist at the contact portion between the convex portion 37a and the concave portion 39a is about 7.5 °.

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

In this embodiment, the image forming apparatus main body 14
Is provided with a body shaft coupling device. In this main body shaft coupling device, a coupling concave shaft 39b (cylindrical shape) is disposed at a position substantially coinciding with the axis of the photosensitive drum 7 when the process cartridge B is mounted on the device main body 14 (FIG. 11). reference). This coupling concave shaft 39b is shown in FIG.
As shown in FIG.
This is a drive shaft integrated with the large gear 43 for transmitting to the drive shaft. The coupling concave shaft 39b is provided at the rotation center of the large gear 43 and protrudes from a side end of the large gear 43 (see FIGS. 19 and 20).

In the above configuration, as described above, the protrusion 37
a concave portion 37b at the center of the tip and convex portion 3 at the center of the bottom surface of the concave portion 39a
By fitting 9d, the rotation center of the large gear 43 and the rotation center of the photosensitive drum 7 can be accurately positioned, and the ridge line of the coupling convex portion 37a due to the load fluctuation when the process cartridge B rotates. The looseness of the contact between the 37a1 and the inner surface 39a1 of the concave portion 39a and the uneven rotation of the coupling drive can be minimized, and the rotation accuracy of the photosensitive drum 7 can be improved (see FIG. 24). . Here, the convex shaft 37 and the convex portion 37 are used.
“a” is provided on the drum flange 36 so as to be coaxial with the axis of the photosensitive drum 7 when the drum flange 36 is attached to one end of the photosensitive drum 7. Reference numeral 36b denotes a fitting portion, which is a drum flange 36.
This is a portion that fits on the inner surface of the drum cylinder 7d when is mounted on the photosensitive drum 7. The drum flange 36 is attached to the photosensitive drum 7 by "caulking" or "adhesion". The photosensitive layer 7e is coated around the drum cylinder 7d (see FIGS. 11 and 15).

The other end of the photosensitive drum 7 has
The drum flange 34 is fixed. The spur gear 7n is integrally formed with the drum flange 34 (see FIG. 11).

It is to be noted that the process cartridge B is attached to the main assembly 1 of the apparatus.
4, the cylindrical guide 13aL is fitted and positioned in the U-shaped positioning groove 16b (see FIG. 9) of the apparatus main body 14, and the spur gear 7n formed integrally with the drum flange 34 is formed. The gear meshes with a gear (not shown) that transmits a driving force to the transfer roller 4.

The drum flanges 34 and 36 may be made of polyacetal.
l), polycarbonate (polycarbonat)
e), polyamide (polyamide) and polybutylene terephthalate (polybutylenenet)
(e.g., elephthalate). However, other materials may be appropriately selected and used.

A cylindrical boss 38 a concentric with the convex shaft 37 is integrally formed around a convex portion 37 a of the coupling convex shaft 37 of the process cartridge B with a bearing 38 fixed to the cleaning frame 13. (See FIG. 11). The process cartridge B is formed by the boss 38a.
The coupling convex portion 37a is protected when attaching and detaching the
Protected from damage and deformation due to external force. Therefore, it is possible to prevent rattling and vibration at the time of coupling driving due to damage to the convex portion 37a.

The shape of the boss 38a is not limited to the circular shape shown in the present embodiment, but may be guided by the guide portion 16c.
As long as it can be just fitted to d, for example, it may be not a perfect cylindrical shape but a partially circular arc shape. Further, in the present embodiment, an example is shown in which a bearing 38 for rotatably supporting the coupling convex shaft 37 and a cylindrical boss 38a are integrally formed and screwed to the cleaning frame 13 (not shown). However, the bearing 38 and the boss 38a may be separate bodies (see FIG. 11).

In this embodiment, the drum flange 34 is fitted to the drum shaft 7a integrated with the cylindrical guide 13aL provided on the cleaning frame 13 (FIG. 11).
The photosensitive drum 7 is attached to the cleaning frame 13 of the process cartridge B in a state where the coupling convex shaft 37 is fitted to the inner surface of the bearing 38 attached to the cleaning frame 13. I have. Then, the photosensitive drum 7 rotates around the coupling convex shaft 37 and the drum shaft 7a. In the present embodiment,
The photosensitive drum 7 is attached to the cleaning frame 13 so as to be movable in the axial direction as shown in FIG. This is because the mounting tolerance was considered. However, the present invention is not limited to this, and the photosensitive drum 7 may be attached to the cleaning frame 13 so as not to move in the axial direction. That is, the end face 7b1 of the drum flange 36 (the end face of the helical gear 7b) is connected to the end face 38 of the bearing 38.
b, and the end face 34a of the drum flange 34 may be slidably contacted with the step 7a3 of the drum shaft 7a fixed to the cleaning frame 13.

On the other hand, the image forming apparatus main body 14 is provided with a main body shaft coupling device. In this main body shaft coupling device, a coupling concave shaft 39b (cylindrical shape) is disposed at a position substantially coinciding with the axis of the photosensitive drum 7 when the process cartridge B is mounted on the device main body 14 (FIG. 11). reference). As shown in FIG. 18, the coupling concave shaft 39b is a drive shaft integrated with the large gear 43 that transmits the driving force of the motor 61 to the photosensitive drum 7. The coupling concave shaft 39b and the convex portion 39d at the bottom of the concave shaft are provided.
Is a rotation center of the large gear 43 and is provided so as to protrude from a side end side of the large gear 43 (FIGS. 17, 19, and 2).
0). In this embodiment, the large gear 43, the coupling concave shaft 39b and the convex portion 39d at the bottom of the concave shaft are formed by integral molding.

The large gear 43 on the side of the apparatus main body 14 is constituted by a helical gear.
As shown in FIG. 1, a small helical gear 62 fixed to a shaft 61a of a motor 61 is engaged with the small gear 62. When a driving force is transmitted from the small gear 62, the coupling concave shaft 39b is connected to the convex shaft 37. It has teeth with a twist direction and an inclination angle that generate a thrust to move in the direction. The concave portion 39a is the tip of the coupling concave shaft 39b,
9b and the center of rotation of the convex portion 39d at the bottom of the concave shaft.

In this embodiment, the driving force is fixed to the motor shaft 61a and the driving force is transmitted directly from the small gear 62 to the large gear 43. However, the gear train is used to reduce and transmit the driving force, or a belt and a pulley are used. A pair of friction rollers, a timing belt and a pulley may be used.

Next, a configuration in which the concave portion 39a and the convex portion 37a are fitted in conjunction with the closing operation of the opening / closing member 35 is shown in FIG.
This will be described with reference to FIGS.

As shown in FIG. 23, a side plate 67 is fixedly provided between the side plate 66 provided on the apparatus main body 14 and the large gear 43. The side plates 66, 67 are integrally formed at the center of the large gear 43. The provided coupling concave shaft 39b is rotatably supported. An outer cam 6 is provided between the large gear 43 and the side plate 66.
3 and the inner cam 64 are densely inserted. The inner cam 64 is fixed to the side plate 66, and the outer cam 63 is rotatably fitted to the coupling concave shaft 39b. The axially opposed surface of the outer cam 63 and the inner cam 64 is a cam surface, which is a threaded surface that is in contact with the coupling concave shaft 39b. A compression coil spring 68 is compressed between the large gear 43 and the side plate 67 and inserted into the coupling concave shaft 39b.

As shown in FIG. 21, an arm 63a is provided radially from the outer periphery of the outer cam 63.
Of the opening and closing member 3 from the fulcrum 35a of the opening and closing member 35
In the state in which 5 is closed, the position of the end opposite to the open side end of the opening / closing member 35 in the radial direction obliquely downward to the left in FIG. 21 is connected to one end of one link 65 by a pin 65a. . The other end of the link 65 is a pin 65b and an arm 63a.
With the tip of the

FIG. 22 is a view of FIG. 21 viewed from the right. When the opening / closing member 35 is closed, the link 65, the outer cam 63 and the like are in the positions shown in FIG.
And the concave portion 39a are engaged with each other, so that the driving force of the large gear 43 can be transmitted to the photosensitive drum 7. When the opening / closing member 35 is opened, the pin 65a rotates about the fulcrum 35a and rises, the arm 63a is pulled up via the link 65, and the outer cam 63 rotates, so that the outer cam 63 and the inner cam 64 face each other. The cam surface slides and the large gear 43 moves in a direction away from the photosensitive drum 7. At this time, the large gear 43 is pushed by the outer cam 63, and moves while pressing the compression coil spring 68 attached between the side plate 67 and the large gear 43.
As shown in (5), the coupling concave portion 39a is separated from the coupling convex portion 37a, the coupling is released, and the process cartridge B becomes detachable.

Conversely, when the cover 35 is closed, the pin 65a connecting the open / close member 35 and the link 65 is moved to the fulcrum 35.
23, the link 65 moves downward and pushes down the arm 63a, and the outer cam 63 rotates in the opposite direction and is pushed by the spring 68, so that the large gear 43 moves leftward from FIG. When the gear reaches the position shown in FIG.
And the coupling concave portion 39a is fitted to the coupling convex portion 37a, and returns to a state where the drive can be transmitted.
With such a configuration, the process cartridge B can be made detachable and drivable according to the opening and closing of the opening and closing member 35. When the opening / closing member 35 is closed, the outer cam 63 rotates in the reverse direction, the large gear 43 moves leftward from FIG. 23, and the coupling concave shaft 39b and the end surface of the coupling convex shaft 37 come into contact with each other, so that the coupling convex portion 37
Even when the image forming apparatus A does not mesh with the coupling recess 39a, the meshing occurs immediately after the image forming apparatus A is started.

As described above, in the first embodiment, when the process cartridge B is attached to or detached from the apparatus main body 14, the opening / closing member 35 is opened. In conjunction with the opening / closing of the opening / closing member 35, the coupling recess 39a moves in the horizontal direction (arrow j).
Direction). Therefore, when the process cartridge B is attached to and detached from the apparatus main body 14, the couplings (37a, 39a) of the process cartridge B are not connected. They are not linked. Therefore, the process cartridge B can be smoothly attached to and detached from the apparatus main body 14. In the first embodiment, the coupling recess 39a is pressed in the direction of the process cartridge B by the large gear 43 being pressed by the compression coil spring 68. Therefore, the coupling convex portion 37a and the concave portion 3
Even when the coupling convex portion 37a and the concave portion 39a collide with each other and do not mesh well when 9a meshes with each other,
Only after the process cartridge B is mounted on the apparatus main body 14 is the motor 61 rotated, whereby the coupling recess 3 is rotated.
As the 9a rotates, the two mesh instantly.

Next, the operation of the convex portion 37a and the concave portion 39a which are the engaging portions of the coupling means will be described.

The coupling concave shaft 39b provided on the apparatus main body 14 is movable in the axial direction as described above, but is supported so as not to move in the radial direction (radial direction). On the other hand, the process cartridge B is mounted on the apparatus main body 14 so as to be movable in the longitudinal direction. In addition,
When the process cartridge B is movable in the longitudinal direction, the photosensitive drum 7 may or may not be movable in the longitudinal direction with respect to the cartridge frame. Further, the process cartridge B may be mounted so as not to move in the longitudinal direction with respect to the apparatus main body 14. In this case,
The photosensitive drum 7 is mounted movably in the longitudinal direction of the cartridge frame.

That is, when the process cartridge B is mounted on the apparatus main body 14, the drum shaft 7a into which the drum flange 34 attached to the other longitudinal end of the photosensitive drum 7 is fitted.
The cylindrical guide 13aL concentric with the drum flange 34 (see FIG. 11) enters the positioning groove 16b (see FIG. 9) of the apparatus main body 14 and is fitted and positioned without a gap. Tooth gear 7n is transfer roller 4
And a gear (not shown) for transmitting a driving force to the gear. On the other hand, at one end (drive side) in the longitudinal direction of the photosensitive drum 7, a boss 38a provided on the cleaning frame 13 is
Is fitted and positioned in the positioning groove 16d (see FIG. 10) provided in the first groove. When the opening / closing member 35 is closed as described above, the concave portion 39a moves horizontally and enters the convex portion 37a (see FIG. 24).

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

First, when the main drive motor 61 rotates, the coupling concave shaft 39b is urged in the direction of the coupling convex shaft 37 (the direction of the arrow d in FIG. 19), and is pushed and engaged by the compression coil spring 68. When there is no phase between the convex portion 37a and the concave portion 39a (in the present embodiment, since the shape connecting the tip of the rib of the convex portion 37a and the concave portion 39a are substantially equilateral triangles, both phases match each other at 120 °). ) To engage both,
The rotational force is transmitted from the apparatus main body 14 to the process cartridge B (from the state shown in FIG. 19 to the state shown in FIG. 20).

At the time of this coupling engagement, the projection 37a
When enters into the concave portion 39a, as shown in FIG.
There is a difference between the sizes of the substantially equilateral triangles, that is, the recess 39a.
Is larger than a substantially equilateral triangle having a shape connecting the tips of the protrusions 37a and the ribs 37c, so that the hole smoothly enters with a gap.

Therefore, when the image is formed, the convex portion 37a is
When the coupling concave shaft 39 rotates in a state where the coupling concave shaft 39 is inserted into the inner surface 39a1 of the concave portion 39a, as shown in FIG.
And the ridge 37a1 at the rib tip of the convex portion 37a abuts to transmit the driving force. In the state where the convex portion 37a has entered the concave portion 39a, the convex portion 39c at the center of the concave bottom surface is fitted to the concave portion 37b at the center of the convex portion front end, and the axis is aligned.

In this embodiment, since the axes are aligned, the process cartridge B is restricted from moving downward by a predetermined distance substantially perpendicular to the axis of the photosensitive drum 7. Therefore, the outer surface of the boss 38a as the cartridge positioning portion comes into contact with the extending portion 50 (see FIG. 32) of the guide portion 16 as the main body positioning portion.

On the other hand, the convex portion 37a and the concave portion 39a are a multi-threaded rib 37c having the same twisted ridgeline 37a1, a twisted inner surface 39a1, and a twisted hole having a polygonal cross section at the contact portion. When the joint is engaged and operated, a thrust is generated in the axial direction at a contact portion between the ridge line 37a1 of the convex portion 37a and the inner surface 39a1 of the concave portion 39a. Since the direction in which the thrust is generated is determined by the direction in which the concave portion 39a pulls in the convex portion 37a, the twist direction of the convex portion 37a and the concave portion 39a is determined.
When the photosensitive drum 7 is supported so as to be movable in the axial direction with respect to the cleaning frame 13, the end surface 37a2 of the convex portion 37a abuts the bottom surface 39a2 of the concave portion 39a. The longitudinal position is determined.

When the process cartridge B is mounted on the apparatus main body 14, the side plate of the cleaning frame 13, for example, is brought into contact with the mounting guide member 16R on the driving side so as to determine the position in the longitudinal direction. in case of,
The coupling flange 37a moves in the axial direction with respect to the coupling recess 39a, and the end face 7b1 of the drum gear 7b of the drum flange 36 is fixed to the bearing 38 so that the end face 37a2 of the projection 37a does not abut the recess bottom 39a2. You may make it contact | abut on the inner end surface 38b.

When the photosensitive drum 7 is attached to the cartridge frame so as not to move in the longitudinal direction, the process cartridge B can be moved in the longitudinal direction with respect to the apparatus main body 14, and as described above. The convex portion 37a is formed by the thrust when the convex shaft 37 is driven by the coupling concave shaft 39b.
The end face 37a2 of the photosensitive drum 7 is in contact with the bottom face 39a2 of the concave portion, whereby the position of the photosensitive drum 7 in the longitudinal direction is determined. Also,
Also in this case, the process cartridge B is positioned so as to abut against the guide member 16R on the longitudinal drive side, and the force for moving and pressing the process cartridge B to the drive side guide member 16R is provided by the concave portions 39a and the convex portions 37a.
It may be based on the thrust generated at the time of rotation. However, in this case,
The process cartridge B is brought into contact with the guide member 16R while the convex end face 37a2 and the concave bottom face 39a2 do not contact each other.

The above description is based on the assumption that the coupling concave shaft 39b and the convex shaft 37 generate the thrust that attracts in the axial direction.
Although the a and the concave portion 39a are formed as a multi-threaded rib 37c and a polygonal twisted hole, the twist direction may be reversed so as to urge the photosensitive drum 7 toward the non-drive side during operation. . However, in this case, in any case, the process cartridge B needs to use the non-driving side of the cartridge mounting portion of the apparatus main body 14 as the longitudinal positioning reference.

With the above configuration, the boss 38a of the cartridge positioning portion and the main body positioning portion 50 come into contact with each other, and the photosensitive drum 7 of the process cartridge B
And a position substantially perpendicular to the axis of. Further, a rotational force is generated in the process cartridge B by transmitting the driving force to the photosensitive drum 7, and the rotational force is provided on the upper surface of the cleaning frame 13 of the process cartridge B as a regulating contact provided as a surface parallel to the longitudinal direction. The part 13j (FIG. 4)
To FIG. 6) against the fixing member 25 (see FIGS. 9 and 10) fixed to the image forming apparatus main body 14.

Further, at the time of non-driving (at the time of non-image formation), a gap is provided in the radial direction (radial direction) between the convex portion 37a and the concave portion 39a, so that attachment and detachment of the shaft coupling members becomes easy. 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. Further, the vibration of the process cartridge B can be suppressed by the contact between the boss 38a of the cartridge positioning portion and the main body positioning portion 50.

In this embodiment, the concave portion 39a
The main body positioning portion 50 and the boss 38a of the cartridge positioning portion may come into contact with each other at a position where the axis of the convex portion 37a and the convex portion 37a coincide with each other.
The axes may not be aligned. However, even if the axes do not match, it is natural that the amount of deviation is within a range in which an image of the quality required for practical use can be obtained.

In the present embodiment, the coupling convex portion has three equally arranged ribs and the concave portion has a substantially regular triangle shape. However, the convex portion 37a has a multi-threaded rib, and the concave portion has a concave shape. 3
It is needless to say that the same effect can be obtained if 9a is a substantially regular polygonal shape. If the concave portion 39a is a substantially regular polygonal shape, positioning can be performed more accurately. The rib 37c provided on the 37a is not limited to the number of sides of the polygon and may be a single twisted rib 37c as shown in FIG. 29 as long as it can be fitted and pulled. Good. In the case of FIG. 29, the convex portion 39d extending in the axial direction from the bottom surface 39a2 of the coupling concave shaft 39b is projected from the end surface of the concave shaft 39b, and the convex portion 39d is first fitted into the concave portion 37b of the coupling convex portion 37a. After centering, the rib 37c is brought into contact with the inner surface 39a1 of the recess.

Furthermore, when the coupling convex portion and the concave portion are compared, the convex portion is easily damaged in shape, and is inferior in strength to the concave portion. For this reason, in the present embodiment, a coupling convex portion is provided in the process cartridge B so as to be replaceable, and a coupling concave portion is provided in the image forming apparatus main body 14 requiring higher durability. However, a coupling concave portion may be provided in the process cartridge B, a coupling convex portion may be provided in the apparatus body 14, and the driving force may be transmitted by fitting the convex portion and the concave portion.

(Embodiment 2) Next, the shape of the convex portion 37a of the other coupling convex shaft 37 and the concave portion 39a of the coupling concave shaft 39b and the apparatus main body 1 of the process cartridge B are described.
FIG. 25 shows another embodiment 2 for positioning with respect to FIG.
This will be described with reference to FIG. Note that the basic configurations of the process cartridge B and the image forming apparatus A are the same as those in the first embodiment described above, and will not be described repeatedly, and members having the same functions as those in the first embodiment will be denoted by the same reference numerals. Is attached.

The shape of the convex portion 37a in the second embodiment is a rectangular prism twisted as shown in FIG. 25, and the concave portion 39a fitted with the convex portion 37a is a rectangular column hole in which the concave space is twisted. is there. The concave portion 3 is located at the center of the tip of the convex portion 37a.
7b, a projection 39d is provided at the center of the bottom surface 39a2 of the recess 39a. In addition, as the direction of the twist, the convex portion 37a
Is a direction opposite to the rotation direction when viewed from the center to the end of the photosensitive drum 7, and the recess 39 a is a direction opposite to the rotation direction when viewed from the photosensitive drum 7 side to the outside of the apparatus main body 14. Twisted. Then, when the convex portion 37a and the concave portion 39a provided in the apparatus main body 14 are fitted and the rotational force of the concave portion 39a is transmitted to the convex portion 37a, the ridge line 37 of the convex portion 37a is formed.
Since a1 and the inner surface 39a1 of the concave portion 39a are approximately in contact with each other, the driving force is stably transmitted, and since the inner surfaces of the convex portion 37a and the concave portion 39a are twisted in the above-described directions, a force acts in the direction of pulling each other. The end face 37a2 of the convex portion 37a and the bottom surface 39a2 of the concave portion come into contact with each other,
, The position of the process cartridge B in the axial direction of the photosensitive drum 7 is determined. Furthermore, a concave portion 37b at the center of the tip of the convex portion
The convex portion 39d at the center of the concave bottom surface is fitted to the
a and the axis of the concave portion 39a are accurately positioned.

In the second embodiment, the projections 3
The shape of the recess 7a and the recess 39a is a twisted quadrangular prism. However, the shape is not limited to this, and other polygonal pillars such as a triangular prism shown in FIG.
7a has a coupling convex shaft 37 as shown in FIG.
The support shaft 37a5 projects from the center of the end face of the
The inner surface 39a1 of the recess 39a is provided at the tip of a plurality of arms 37a4 extending in the radial direction of the support shaft 37a5 from the tip of 7a5.
Even if the shape has a spherical contact portion 37a3 that comes into contact with each other, an axial force acts at the time of driving, so that any shape that exerts a thrust at the time of driving may be used.

Further, one arm 37a4 may have a spherical contact portion 37a3 at the tip thereof (see FIG. 30). However, at this time, the concave portion 37b at the center of the convex portion tip and the convex portion 39d at the center of the concave portion bottom are connected to the coupling concave portion 39a so that the arm reliably contacts the inner surface 39a1 of the concave portion 39a.
It is desirable that the positional relationship be such that the first engagement occurs when is moved in the axial direction (see FIG. 31). For this reason, the arm 37a4 is provided on the convex portion 37a at a position retracted toward the photosensitive drum 7 from the convex end surface 37a2.

The driven and drive side shaft couplings (37
a, 39a) both have a twisted surface in the projection or hole,
Only one of the shaft coupling portions may have a twisted surface. Alternatively, as shown in FIG.
Both 7a and 39a may have no twist.
In such a case, when the process cartridge is mounted on the main body of the image forming apparatus, the leaf spring 1 is biased in the axial direction.
When 7 or the like is provided in the apparatus main body 14 (see FIG. 32) or the process cartridge B (see FIG. 33), the backlash in the axial direction can be suppressed.

[0107]

As described above, according to the present invention,
The position substantially perpendicular to the axis of the electrophotographic photosensitive member is determined by the contact between the cartridge positioning portion and the main body positioning portion. Furthermore, when the process cartridge is provided with a shaft coupling member that generates an engagement rotational thrust with a shaft coupling member on the image forming apparatus main body side, the axial positioning of the electrophotographic photosensitive drum can be performed with high accuracy.

[Brief description of the drawings]

 Each of the drawings shows an embodiment of the present invention,

FIG. 1 is a longitudinal sectional view of an electrophotographic image forming apparatus.

FIG. 2 is an external perspective view of the apparatus shown in FIG.

FIG. 3 is a vertical sectional view of the process cartridge.

4 is an external perspective view of the process cartridge shown in FIG. 3 as viewed from the upper right side.

FIG. 5 is a right side view of the process cartridge shown in FIG.

FIG. 6 is a left side view of the process cartridge shown in FIG.

7 is an external perspective view of the process cartridge shown in FIG. 3 as viewed from the upper left side.

FIG. 8 is an external perspective view showing a lower left side of the process cartridge shown in FIG. 3;

FIG. 9 is an external perspective view of a process cartridge mounting portion of the apparatus main body.

FIG. 10 is an external perspective view of a process cartridge mounting portion of the apparatus main body.

FIG. 11 is a longitudinal sectional view of a photosensitive drum and a driving device thereof.

FIG. 12 is a perspective view of a cleaning unit.

FIG. 13 is a perspective view of a developing unit.

FIG. 14 is a perspective view of a drum flange (a driving force transmitting component) according to the embodiment.

FIG. 15 is a perspective view of a photosensitive drum according to the embodiment.

FIG. 16 is a perspective view of a shaft coupling portion of the process cartridge according to the embodiment.

FIG. 17 is a perspective view of the shaft coupling according to the embodiment.

FIG. 18 is a sectional view showing a drive system of the main body of the electrophotographic image forming apparatus according to the embodiment.

FIG. 19 is a perspective view of a shaft coupling member provided on the apparatus main body according to the embodiment and a shaft coupling member provided on the process cartridge.

FIG. 20 is a perspective view of a shaft coupling member provided in the apparatus main body according to the embodiment and a shaft coupling member provided in the process cartridge.

FIG. 21 is a longitudinal sectional view illustrating a configuration of a cover and a shaft coupling portion of the apparatus main body according to the embodiment.

FIG. 22 is a side view illustrating a configuration around a coupling concave axis when the process cartridge of the apparatus main body according to the embodiment is driven.

FIG. 23 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.

FIGS. 24A and 24B are cross-sectional views of a coupling convex portion and a concave portion according to the embodiment.

FIG. 25 is a perspective view of a shaft coupling according to another embodiment.

FIG. 26 is a perspective view of a shaft coupling showing another embodiment.

FIG. 27 is a perspective view of a shaft coupling according to another embodiment.

FIG. 28 is a perspective view of a shaft coupling according to another embodiment.

FIG. 29 is a perspective view of a shaft coupling according to another embodiment.

FIG. 30 is a perspective view of a shaft coupling according to another embodiment.

FIG. 31 is a schematic plan view showing a longitudinal relationship among a photosensitive drum, a process cartridge, an apparatus main body, and a shaft coupling.

FIG. 32 is a schematic plan view showing a relationship between a photosensitive drum, a process cartridge, an apparatus main body, and a shaft coupling in a longitudinal direction.

FIG. 33 is a schematic plan view showing the relationship in the longitudinal direction among the photosensitive drum, the process cartridge, the apparatus main body, and the shaft coupling.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical system 1a ... Laser diode 1b ... Polygon mirror 1c ... Lens 1d ... Reflection mirror 1e ... Exposure opening 2 ... Recording medium 3 ... Conveying means 3a ... Paper feed cassette 3b ... Pickup rollers 3c, 3d ... Conveyance roller pair 3e ... Registration roller pair 3f Transport guide 3g, 3h, 3i Discharge roller pair 3j Reverse path 3k Flapper 3m Discharge roller pair 4 Transfer roller 5 Fixing means 5a Heater 5b Fixing roller 5c
... Driving roller 6 ... Discharge tray 7 ... Photoconductor drum 7a ... Drum shaft 7a2 ... Expanded diameter section
7a3 Stepped portion 7b Drum gear 7b1 End face 7d
... drum cylinder 7e ... photosensitive layer 7n ... spur gear 8 ... charging roller 9 ... developing means 9b ... toner feeding material 9c ... developing roller 9d ... developing blade 9e ... toner stirring member 9h ... antenna rod 9i ... spacer roller 9j ... developing roller bearing 9k developing roller gear 9v bearing box 10 cleaning means 10a cleaning blade 10b waste toner reservoir 11 toner frame 11A toner container 11a upper frame 11a1 flange 11b lower frame 11b
DESCRIPTION OF SYMBOLS 1 ... Flange 11c ... Rib 11i ... Toner supply opening 12 ... Developing frame 13 ... Cleaning frame (drum frame) 13aR1 ...
Flange 13aR2 ... Machine screw 13aR, 13aL ...
Cylindrical guide 13bR, 13bL ... detent guide
13c: Positioning pin 13d: Small screw 13e: Mounting hole 13f: Restricting contact part 13i: Upper surface 13j: Restricting contact part 13L: Guide member 13n: Transfer opening part 1
3p ... right end 13q ... left end 13R ... guide member
13R3 Positioning portion 13s Side plate 13t Partition wall 14 Image forming apparatus main body 16 (16R, 16L) Guide member 16a Guide portion 16b Positioning groove 16c Guide portion 16d
Positioning groove 16f Positioning part 17 Plate spring 18 Drum shutter member 18a Shutter cover 18b, 18c link 18c1 Projecting part 19 Arm part 20 Rotating hole 21 Depression 22 Joint member 22a Compression coil spring 25 Fixed member 33 ... leaf spring 34 ... drum flange 34a ... end surface 35 ... opening and closing member 35a ... fulcrum 36 ... drum flange 36a ... fitting part 37 ... coupling convex shaft 37a ... convex part (driven side shaft coupling part) 37a1 ... Ridge 37a2 ... End face 37a3 ...
Spherical contact portion 37a4 ... arm 37a5 ... support shaft 3
7a8: spherical contact portion 37a9: ridge line 37b: concave portion
37c ... rib 38 ... bearing 38a ... boss 38b ... inner end surface 39a ... concave portion (drive side shaft coupling portion) 39a1 ... inner surface 3
9a2 Bottom surface 39b Coupling concave shaft 39d Convex portion 40 Developing holder 43 Large gear 50 Extended guide portion (main body positioning portion) 61 Motor 61a Shaft 62 Small gear 63 Outer cam 63a Arm 64 ... Inner cam 65 ... Link 65a, 65b ... Pin 66 ... Side plate 67 ... Side plate 68 ... Compression coil spring A ... Laser beam printer (image forming apparatus) B ... Process cartridge C ... Cleaning unit D ... Development unit JP ... Coupling surface K ... Slope

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Akika Yokoi 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 2H035 CA07 CB01 CD07 CD11 CD14 CG03 2H071 BA13 BA16 CA02 CA05 DA06 DA08 DA13 DA15

Claims (24)

[Claims] 1. A motor, an apparatus body side gear rotatably driven by the motor, a body positioning member, a protrusion extending in the rotation center axis direction of the gear, and provided on the rotation center axis of the protrusion. An electrophotographic photosensitive drum, a process acting on the electrophotographic photosensitive drum, the process cartridge having a connection hole provided, and a projection provided at the bottom of the connection hole. Means, a connection protrusion in contact with the connection hole, the connection protrusion provided at a longitudinal end of the electrophotographic photosensitive drum, and a process cartridge mounted on a cartridge mounting portion provided on the apparatus main body. And a contact portion for aligning by contacting a convex portion provided at the bottom of the connection hole when connecting the connection hole and the connection protrusion. Scan cartridge. 2. The process cartridge according to claim 1, wherein the connection projection has a contact portion that contacts the inner surface of the connection hole at at least one point and transmits a rotational driving force. 3. The process cartridge according to claim 1, wherein the connection protrusion is twisted. 4. The connection projection according to claim 1, wherein said connection projection is not twisted.
Or the process cartridge according to 2. 5. The process cartridge according to claim 1, wherein the connection hole has a substantially polygonal cross section. 6. The substantially polygonal shape is a substantially triangular shape.
The process cartridge according to 1. 7. The connection hole according to claim 1, wherein said connection hole is twisted.
The process cartridge according to any one of 2, 5, and 6. 8. The method according to claim 1, wherein the connection hole is not twisted.
The process cartridge according to any one of 2, 5, and 6. 9. When the electrophotographic photosensitive drum receives rotational driving force via the connection hole and the connection protrusion, the connection protrusion receives a pulling force in the direction of the connection hole.
Or the process cartridge according to 7. 10. The electrophotographic photosensitive drum according to claim 3, wherein when the process cartridge is mounted on the image forming apparatus, the connection protrusion is pressed in the direction of the connection hole and positioned in the axial direction of the electrophotographic photosensitive drum. Process cartridge. 11. The process cartridge according to claim 1, wherein a charging unit, a developing unit or a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge, and the cartridge is detachably mountable to an image forming apparatus main body. 11. The process cartridge according to any one of items 10 to 10. 12. The process cartridge according to claim 1, wherein at least one of a charging unit, a developing unit, and a cleaning unit and an electrophotographic photosensitive member are integrally formed as a cartridge and can be attached to and detached from an image forming apparatus main body. 11. The process cartridge according to any one of items 10 to 10. 13. The process cartridge according to claim 1, wherein at least the developing means and the electrophotographic photosensitive member are integrally formed as a cartridge so as to be detachable from the main body of the image forming apparatus.
11. The process cartridge according to any one of items 1 to 10. 14. A motor, a device main body side gear rotatably driven by the motor, a main body positioning member, a protruding portion extending in the rotation center axis direction of the gear, and a rotation center axis of the protruding portion. An electrophotographic image forming apparatus main body having a connecting hole provided in the electrophotographic image forming apparatus main body and a projecting portion provided on the bottom of the connecting hole, and a process cartridge detachable from the electrophotographic image forming apparatus main body. A photographic photoreceptor drum, a process unit acting on the electrophotographic photoreceptor drum, and a connection protrusion contacting the connection hole, the connection protrusion being provided at a longitudinal end of the electrophotographic photoreceptor drum, A process cartridge in which a process cartridge is mounted on a cartridge mounting portion provided in the apparatus main body and which receives the rotational driving force from the apparatus main body by connecting the connection hole and the connection protrusion; A rotation transmitting member provided between the connecting projections, wherein the connecting projection has the connecting hole and the connecting projection, and the connecting projection has an abutting portion that abuts on the convex portion of the bottom of the connecting hole to perform alignment. And a rotation transmitting member. 15. The rotation transmitting member according to claim 14, wherein the connection protrusion has a contact portion that contacts the inner surface of the connection hole at at least one point and transmits a rotational driving force. 16. The rotation transmitting member according to claim 14, wherein the connection protrusion is twisted. 17. The rotation transmitting member according to claim 14, wherein the connection protrusion is not twisted. 18. The rotation transmitting member according to claim 14, wherein the connection hole has a substantially polygonal cross section. 19. The rotation transmitting member according to claim 18, wherein the substantially polygonal shape is a substantially triangular shape. 20. The connection hole according to claim 1, wherein the connection hole is twisted.
The rotation transmitting member according to any one of 4, 15, 18, and 19. 21. The connection hole according to claim 1, wherein the connection hole is not twisted.
The rotation transmitting member according to any one of 4, 15, 18, and 19. 22. The rotation according to claim 16, wherein when the rotation transmitting member receives a rotational driving force via the connection hole and the connection protrusion, the connection protrusion receives a pulling force in the direction of the connection hole. Transmission member. 23. The electrophotographic photosensitive drum according to claim 16, wherein when the process cartridge is mounted on the image forming apparatus, the connection protrusion is pressed in the direction of the connection hole and positioned in the axial direction of the electrophotographic photosensitive drum. Rotation transmission member. 24. An electrophotographic image forming apparatus which detachably attaches a process cartridge to form an image on a recording medium, comprising: a, a motor; b, a device body side gear driven to rotate by the motor; and c, a body positioning member. D, a protrusion extending in the direction of the rotation center axis of the gear; e, a connection hole provided on the rotation center axis of the protrusion, and the protrusion provided at the bottom of the connection hole; An electrophotographic photosensitive drum; a process unit acting on the electrophotographic photosensitive drum; and a connecting protrusion provided in contact with the connection hole, the connecting protrusion being provided at a longitudinal end of the electrophotographic photosensitive drum. When the process cartridge is mounted on the cartridge mounting portion provided on the apparatus main body and connects the connection hole and the connection protrusion, the process cartridge comes into contact with the projection provided on the bottom of the connection hole and is aligned. An electrophotographic image forming apparatus, comprising: a mounting means for removably mounting a process cartridge having a contact portion which performs the printing operation; and a conveying means for conveying the recording medium.