JP3984999B2 - Process cartridge and electrophotographic image forming apparatus - Google Patents

Description

  The present invention relates to a process cartridge and an electrophotographic image forming apparatus to which the process cartridge can be attached and detached. Here, the electrophotographic image forming apparatus forms an image on a recording medium using an electrophotographic image forming system. Examples of the electrophotographic image forming apparatus include an electrophotographic copying machine, an electrophotographic printer (for example, a laser beam printer, an LED printer, etc.), a facsimile machine, a word processor, and the like.

    The 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, and the cartridge can be attached to and detached from the 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 that can be attached to and detached from the main body of the image forming apparatus. 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. Here, since the process cartridge can be attached to and detached from the apparatus main body by the user himself, maintenance of the apparatus main body can be easily performed.

  An electrophotographic image forming apparatus using an electrophotographic image forming system forms a latent image by performing selective exposure according to image information on an electrophotographic photosensitive drum uniformly charged by a charging unit. Then, the latent image is developed with toner by a developing unit to form a toner image. Thereafter, an image is formed by forming the toner image on the electrophotographic photosensitive drum and transferring the toner image onto a recording medium by a transfer means.

  Conventionally, in an image forming apparatus using an image forming process, the electrophotographic photosensitive drum and the process means acting on the electrophotographic photosensitive drum are integrally formed into a cartridge, and the cartridge can be attached to and detached from the main body of the image forming apparatus. The process cartridge method is adopted. According to this process cartridge system, the apparatus can be maintained by the user himself / herself without depending on the service person, so that the operability can be remarkably improved. Therefore, this process cartridge system is widely used in image forming apparatuses.

    In such a process cartridge, 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 and an electrophotographic photosensitive member serving as a drive source on the image forming apparatus main body side are provided. The body drum is connected.

  Here, various methods have been considered for rotationally driving the electrophotographic photosensitive drum. One method is described in Japanese Patent Laid-Open No. 62-65049, in which a pin fixed to a side surface of a gear provided in the main body of the image forming apparatus is attached to a side surface of the gear provided to the photosensitive drum. This is a method of rotating the photosensitive drum fitted in the provided recess.

  Another method is a method of rotating the photosensitive drum by engaging with a helical gear provided in the main body of the image forming apparatus, as described in JP-A-63-4252.

In such a process cartridge, an earth contact member disposed coaxially with the electrophotographic photosensitive drum is used to ground the electrophotographic photosensitive drum.
JP-A-62-65049 JP-A-63-4252

The present invention is a further development of the prior art.
An object of the present invention is to provide a process cartridge and an electrophotographic image forming apparatus capable of grounding an electrophotographic photosensitive drum.

  Another object of the present invention is a process cartridge capable of grounding the electrophotographic photosensitive drum between the electrophotographic photosensitive member and the apparatus main body in a configuration in which the rotational driving force of the electrophotographic photosensitive member is received from the apparatus main body by coupling, and An 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 and an electrophotographic image forming apparatus capable of grounding the electrophotographic photosensitive member without impairing the rotational accuracy of the electrophotographic photosensitive member.

  Another object of the present invention is to provide a process cartridge having a cartridge-side ground contact provided on a protrusion so as to be electrically connected to a main-body-side ground contact for grounding an electrophotographic photosensitive drum, and electrophotography An object is to provide an image forming apparatus.

A representative present invention for solving the above-mentioned problems is that a motor, an apparatus main body side gear that is rotationally driven by the motor, and an axis of the apparatus main body side gear that are twisted with a substantially triangular section. A hole and a body-side ground contact provided inside the hole, disposed at the center of rotation of the hole, movable in the longitudinal direction, and by the elastic force of a conductive spring, A process cartridge that can be attached to and detached from the electrophotographic image forming apparatus main body, and a main body side earth contact that is a tip of a conductive main body earth contact member that is biased toward the inside,
An electrophotographic photosensitive drum;
Process means acting on the electrophotographic photosensitive drum;
A twisted protrusion having a substantially triangular cross section provided at an end in the longitudinal direction of the electrophotographic photosensitive drum, the protrusion being fitted into the hole when the process cartridge is mounted on the apparatus main body; ,
In order to ground the electrophotographic photosensitive drum between the process cartridge and the apparatus main body when the process cartridge is mounted on the apparatus main body, a cartridge-side ground contact electrically connected to the electrophotographic photosensitive drum is used. A cartridge-side ground contact provided on the protrusion so as to be electrically connected to the body-side ground contact;
Have
The electrophotographic photosensitive drum included in the process cartridge mounted on the apparatus main body is configured such that when the main body side gear receives a rotational driving force from the motor and rotates while the protrusion is fitted in the hole, the protrusion Rotation drive from the motor in a state where the main body side ground contact is urged by the elastic force of the spring toward the cartridge side ground contact in a state where the main body side ground contact is biased toward the cartridge side ground contact Force is transmitted to the electrophotographic photosensitive drum, and the electrophotographic photosensitive drum is electrically grounded to the apparatus main body through the cartridge side ground contact engaged with the main body side ground contact. It is characterized by.

  The present invention can reliably ground the electrophotographic photosensitive drum between the electrophotographic photosensitive drum included in the process cartridge mounted on the main body of the electrophotographic image forming apparatus and the apparatus main body.

  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 short direction of the process cartridge B is a direction in which the process cartridge B is attached to and detached from the apparatus main body 14 and coincides with the conveyance direction of the recording medium. Further, the longitudinal direction of the process cartridge B is a direction (substantially orthogonal direction) that intersects with a direction in which the process cartridge B is attached to and detached from the apparatus main body 14, is parallel to the surface of the recording medium, and transports the recording medium. Is a direction intersecting (substantially orthogonal). The left and right with respect to the process cartridge is the right or left when the recording medium is viewed from above according to the conveyance 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 showing an outline of the external appearance thereof, FIG. 5 is a right side view thereof, FIG. 6 is a left side view thereof, and FIG. FIG. 8 is a perspective view of the process cartridge turned upside down and seen from above. In the following description, the upper surface of the process cartridge B is a surface located on the upper side in a state where the process cartridge B is mounted on the apparatus main body 14, and the lower surface is a surface located on the lower side.

(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). Specifically, the photosensitive drum is charged by a charging unit, and then a laser beam corresponding to the image information is irradiated from the optical unit to the photosensitive drum to form a latent image corresponding to the image information on the photosensitive drum. The latent image is developed by developing means to form a toner image. In synchronization with the formation of the toner image, the recording medium 2 set in the paper feed cassette 3a is reversed and conveyed by the pickup roller 3b, the conveyance roller pairs 3c and 3d, and the registration roller pair 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 the transfer roller 4 as transfer means. 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 5b incorporating a heater 5a. Then, the transferred toner image is fixed by applying heat and pressure to the passing recording medium 2. The recording medium 2 is conveyed by the discharge roller pairs 3g, 3h, 3i, and discharged to the discharge tray 6 through the reverse 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 reverse path 3j. In the present embodiment, the pickup roller 3b, transport roller pairs 3c, 3d, registration roller pair 3e, transport guide 3f, discharge roller pairs 3g, 3h, 3i and discharge roller pair 3m constitute a transport means 3. .

  On the other hand, as shown in FIGS. 3 to 8, the process cartridge B rotates the photosensitive drum 7 having the photosensitive layer 7e (see FIG. 11) and applies a voltage to the charging roller 8 as a charging means. Is uniformly charged. Next, a laser beam corresponding to the image information from the optical system 1 is irradiated onto the photosensitive drum 7 through the exposure opening 1e to form a latent image. 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 rotates following the photosensitive drum 7. The developing unit 9 supplies toner to the developing area of the photoconductor drum 7 to develop the latent image formed on the photoconductor drum 7. The optical system 1 includes a laser diode 1a, a polygon mirror 1b, a lens 1c, and a reflection mirror 1d.

  Here, the developing means 9 sends the toner in the toner container 11A to the developing roller 9c by the rotation of the toner feeding member 9b. Then, the developing roller 9c incorporating the fixed magnet is rotated, and a toner layer to which triboelectric charge is imparted is formed on the surface of the developing roller 9c by the developing blade 9d, and the toner is supplied to the developing region of the photosensitive drum 7. . Then, the toner is transferred to the photosensitive drum 7 in accordance with the latent image, thereby forming a toner image and making it a visible image. Here, the developing blade 9d defines the amount of toner on the peripheral surface of the developing roller 9c and applies a triboelectric charge. A toner agitating member 9e for circulating toner in the developing chamber is rotatably attached in the vicinity of 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, and then the residual toner on the photosensitive drum 7 is removed by the cleaning unit 10. Remove. Here, the cleaning means 10 scrapes off the toner remaining on the photosensitive drum 7 by an elastic cleaning blade 10a provided in contact with the photosensitive drum 7, and collects the toner in the waste toner reservoir 10b.

  The process cartridge B combines a toner frame 11 having a toner container (toner storage unit) 11A for storing toner and a developing frame 12 for holding the developing means 9 such as the developing roller 9c. Further, the cleaning means 10 such as the photosensitive drum 7 and the cleaning blade 10a and the cleaning frame 13 to which the charging roller 8 is attached are coupled to this. The process cartridge B can be attached to and detached from the image forming apparatus main body 14 by an operator.

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

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

  In the process cartridge B shown in the present embodiment, the photosensitive drum 7, the toner frame 11 and the developing frame 12 are coupled to each other, and the cleaning drum 13 is rotatably coupled thereto. The charging roller 8, the developing means 9, the cleaning means 10 and the like are accommodated into a cartridge. Then, the process cartridge B is detachably mounted on a cartridge mounting means provided in the image forming apparatus main body 14.

(Configuration of housing of process cartridge B)
In the process cartridge B according to the present embodiment, the toner frame 11, the developing frame 12, and the cleaning frame 13 are combined to form a housing as described above. Next, the configuration will be described.

  As shown in FIGS. 3 and 20, a toner feeding member 9b is rotatably attached to the toner frame 11. A developing roller 9c and a developing blade 9d are attached to the developing frame 12, and a stirring member 9e for circulating toner in the developing chamber is rotatably attached in the vicinity of the developing roller 9c. Further, as shown in FIGS. 3 and 19, an antenna rod 9h is attached to the developing frame 12 so as to face the longitudinal direction of the developing roller 9c and substantially parallel to the developing roller 9c. The toner frame 11 and the developing frame 12 are welded (ultrasonic welding in the present embodiment) to constitute a developing unit D (see FIG. 13) as an integral second frame.

  A drum shutter member 18 that covers the photosensitive drum 7 when the process cartridge B is removed from the image forming apparatus main body 14 and is exposed to light for a long time or from contact with foreign matter is attached to the toner developing unit. Yes.

  As shown in FIG. 6, the drum shutter member 18 includes 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. As shown in FIGS. 4 and 5, one end of the right link 18 c is pivotally attached to the hole 40 g of the developing holder 40 at both ends in the longitudinal direction of the shutter cover 18 a and upstream in the conveyance direction of the recording medium 2. 6, one end of the left link 18c is pivoted to a boss 11h provided on the lower frame 11b of the toner frame 11 as shown in FIG. The other ends of the links 18c on both sides are pivoted upstream 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 attached 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 connected to the shutter cover 18a at the downstream end in the conveyance direction of the recording medium 2, and the other end is developed. The dowel 12d provided on the frame 12 is pivotally attached. The link 18b is a synthetic resin.

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

  The drum shutter member 18 including the shutter cover 18a and the links 18b and 18c is a torsion coil spring (not shown) inserted into the dowel 12d, one end locked to the link 18b, and the other end locked to the developing device frame 12. The shutter cover 18a is urged so as to cover the transfer opening 13n.

  Further, as shown in FIGS. 3 and 12, the cleaning frame 13 is attached with the members of the photosensitive drum 7, the charging roller 8 and the cleaning means 10, and a cleaning unit C as a first frame (see FIG. 12) is provided. It is composed.

  The developing unit D and the cleaning unit C are coupled to each other by a round pin coupling member 22 to form a process cartridge B. That is, as shown in FIG. 13, a round rotation hole 20 is provided at the tip of the arm portion 19 formed on both sides of the developing frame 12 in the longitudinal direction (axial direction of the developing roller 9c) in parallel to the developing roller 9c. (See FIG. 13). On the other hand, two recesses 21 for entering the arm portion 19 are provided at two locations on both sides in the longitudinal direction of the cleaning frame 13 (see FIG. 12). The arm portion 19 is inserted into the recess 21, the coupling member 22 is press-fitted into the mounting hole 13 e of the cleaning frame 13, and is fitted into the rotation hole 20 at the end of the arm portion 19 and is further press-fitted into the inner hole 13 e. Thus, the developing unit D and the cleaning unit C are coupled so as to be rotatable about the coupling member 22. At this time, the compression coil spring 22a inserted and attached to a dowel (not shown) standing at the base of the arm portion 19 hits the upper wall of the recess 21 of the cleaning frame 13, and the development frame 12 is moved downward by the compression coil spring 22a. By energizing, the developing roller 9c is surely pressed against the photosensitive drum 7. The upper wall of the recess 21 of the cleaning frame 13 is inclined so that when the developing unit D and the cleaning unit C are assembled, the compression coil spring 22a gradually increases the compression from the uncompressed state. 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 opposes at a constant interval (about 300 μm). Therefore, the developing unit D and the cleaning unit C can rotate with respect to the coupling member 22, and therefore, the peripheral surface of the photosensitive drum 7 and the peripheral surface of the developing roller 9 c are caused by the elastic force of the compression coil spring 22 a. The positional relationship can be maintained.

  Since the compression coil spring 22a is attached to the developing device frame 12 on the base side of the arm portion 19 in this manner, the pressure applied by the compression coil spring 22a does not reach other than the arm portion 19 base, and the member attached to the developing device frame 12 Even if there is no particular reinforcement around the spring seat so that the spring seat is a spring seat, the arm 19 has a strong and rigid portion on the base side, which is effective in maintaining accuracy.

  The combined structure of the cleaning frame 13 and the developing frame 12 will be described in detail later.

(Configuration of guide means of process cartridge B)
Next, guide means for attaching / detaching the process cartridge B to / from the apparatus main body 14 will be described. This guide means is shown in FIG. 9 and FIG. 9 is a left perspective view of the process cartridge B when viewed in the direction (arrow X) in which the process cartridge B is attached to the apparatus main body A (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 a guide when the process cartridge B is attached to and detached from the apparatus main body 14 are provided on both outer side surfaces of the cleaning frame 13. ing. The guide means includes cylindrical guides 13aR and 13aL as positioning guide members, and anti-rotation guides 13bR and 13bL as guide members as posture holding means at the time of attachment / detachment.

  As shown in FIG. 5, the cylindrical guide 13aR is a hollow cylindrical member, and the anti-rotation guide 13bR is integrally formed with the cylindrical guide 13aR. The cylindrical guide 13aR is integrally formed from the circumference of the cylindrical guide 13aR in a substantially radial direction. It protrudes. A mounting flange 13aR1 is integrally provided on the cylindrical guide 13aR. In this way, the right guide member 13R having the cylindrical guide 13aR, the non-rotating guide 13bR, and the mounting flange 13aR1 is inserted through the small screw hole of the mounting flange 13aR1 and the small screw 13aR2 is screwed and fixed to the cleaning frame 13. The detent guide 13bR of the right guide member 13R fixed to the cleaning frame 13 is disposed on the side surface of the developing frame 12 so as to extend to the side of a developing holder 40 described later fixed to the developing frame 12. Has been.

  As shown in FIG. 6, the enlarged diameter portion 7a2 of the drum shaft 7a is fitted in the hole 13k1 (see FIG. 11) of the cleaning frame 13. Then, it is fitted to a positioning pin 13c protruding from the side surface of the cleaning frame 13 and is prevented from rotating, and outwardly (perpendicular to the paper surface of FIG. 6) to a flat flange 29 fixed to the cleaning frame 13 with a machine screw 13d. A cylindrical guide 13aL is provided so as to project toward the front side. Inside the flange 29, there is provided the fixed drum shaft 7a for rotatably supporting a spur gear 7n fitted in the photosensitive drum 7 (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 are integrally or integrally made of a metal material such as iron.

  As shown in FIG. 6, the cleaning guide 13 is integrally formed with the cleaning guide 13 so that the detent guide 13 bL, which is slightly separated from the cylindrical guide 13 aL and protrudes in the radial direction of the cylindrical guide 13 aL, protrudes to the side of the cleaning guide 13. Has been. The flange 29 is notched at the part where the rotation prevention guide 13bL interferes with the flange 29, and the height of the rotation prevention guide 13bL protruding to the side is such that the top surface substantially coincides with the top surface of the cylindrical guide 13aL. is there. The anti-rotation guide 13bL extends to the side of the developing roller bearing box 9v fixed to the developing frame 12. Thus, the left guide member 13L is provided as a separate member by separating the cylindrical guide 13aL made of metal and the anti-rotation guide 13bL made of synthetic resin.

  Next, the regulation contact portion 13j provided on 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 the present embodiment, as shown in FIGS. 4 to 7, on the upper surface 13i of the cleaning unit C, the right and left ends 13p and 13q perpendicular to the process cartridge mounting direction are respectively in contact with the restricting contact portions 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 apparatus image forming body 14, the restricting contact portion 13 j is brought into contact with the fixed member 25 (see FIGS. 9, 10, and 30) provided on the image forming apparatus body 14. In contact therewith, the process cartridge B has a rotational position centered on the cylindrical guides 13aR and 13aL.

  Next, guide means on the image forming apparatus main body 14 side will be described. When the opening / closing member 35 of the image forming apparatus main body 14 is pivoted counterclockwise in FIG. 1 about 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 is shown in FIGS. looks like. As shown in FIG. 9 on the left side and FIG. 10 on the right side, guide members 16R and 16L are seen from the opening where the opening / closing member 35 is opened, as viewed from the attaching / detaching direction of the process cartridge B on the left and right inner walls of the image forming apparatus main body 14. Is provided.

  As shown in the figure, the guide members 16R and 16L are respectively connected to the guide portions 16a and 16c which are obliquely provided so as to be forward and downward as viewed from the arrow X in the insertion direction of the process cartridge B, and to the guide portions 16a and 16c, respectively. Semi-circular positioning grooves 16b and 16d into which the cylindrical guides 13aR and 13aL of the process cartridge B are just inserted are provided. The positioning grooves 16b and 16d have a cylindrical peripheral wall. The centers of the positioning grooves 16b and 16d coincide with the centers 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, and therefore coincide with the center line of the photosensitive drum 7.

  The widths of the guide portions 16a and 16c are such that the cylindrical guides 13aR and 13aL are loosely fitted when viewed from the attaching / detaching direction of the process cartridge B. The non-rotating guides 13bR and 13bL each having a narrower width than the diameter of the cylindrical guides 13aR and 13aL naturally fit loosely, but the cylindrical guides 13aR and 13aL and the non-rotating guides 13bR and 13bL are rotated by the guide portions 16a and 16c. The process cartridge B is mounted while maintaining a certain range of postures. 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 fitted in the positioning grooves 16b and 16d of the guide members 13R and 13L, respectively. The restriction contact portions 13j on the left and right ends of the cleaning frame 13 are in contact with the fixed member 25 of the apparatus main body 14.

  The process cartridge B described above has a weight distribution such that when the center line connecting the centers of the cylindrical guides 13aR and 13aL is kept horizontal, the developing unit D side generates a larger primary moment than the cleaning unit C side.

  For mounting the process cartridge B to the image forming apparatus main body 14, the ribs 11c on the concave portion 17 side and the lower side of the toner frame 11 are held with one hand, and the cylindrical guides 13aR and 13aL are respectively held on the image forming apparatus main body 14. The guides 16a and 16c of the cartridge mounting unit are inserted, and then the rotation guides 13bR and 13bL are inserted into the guides 16a and 16c of the main body 14 of the image forming apparatus 14 with the process cartridge B forward and downward as viewed from the insertion direction. The cylindrical guides 13aR and 13aL of the process cartridge B and the anti-rotation guides 13bR and 13bL proceed to the back side along the guide portions 16a and 16c of the main body 14 of the image forming apparatus, and the cylindrical guides 13aR and 13aL of the process cartridge B form the image. When reaching the positioning grooves 16b and 16d of the apparatus main body 14, the cylindrical guides 13aR and 13aL are seated by the gravity of the process cartridge B at the positions of the positioning grooves 16b and 16d. Thereby, the cylindrical guides 13aR and 13aL of the process cartridge B are accurately positioned 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 roughly determined in the image forming apparatus main body 14. Note that the position of the photosensitive drum relative to the apparatus main body 14 is finally determined in a state where the coupling is coupled.

  In this state, there is a slight gap between the fixed member 25 of the image forming apparatus main body 14 and the regulation contact portion 13j of the process cartridge B. Here, when the hand holding the process cartridge B is released, the process cartridge B is lowered on the developing unit D side and centered on the cylindrical guides 13aR and 13aL, and is raised on the cleaning unit C side. 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 rotated clockwise around the fulcrum 35a in FIG.

  The process cartridge B is removed from the apparatus main body 14 in the reverse manner as described above. When the opening / 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 lifted by hand, The cylindrical guides 13aR and 13aL of the process cartridge B rotate about the positioning grooves 16b and 16d of the apparatus main body 14, and the regulation contact portion 13j of the process cartridge B is separated from the fixing member 25 of the apparatus main body 14. When the process cartridge B is further pulled, the cylindrical guides 13aR and 13aL escape from the positioning grooves 16b and 16d and move to the guide portions 16a and 16c of the guide members 16R and 16L fixed to the apparatus main body 14, and the process cartridge is left as it is. When B is pulled up, the cylindrical guides 13aR and 13aL and the anti-rotation guides 13bR and 13bL of the process cartridge B are moved up in the guide portions 16a and 16c of the apparatus main body 14 and thereby the posture of the process cartridge B is regulated. Thus, 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 gear 7b in the axial direction. When the process cartridge B is mounted on the apparatus main body 14, the spur gear 7n meshes with a gear (not shown) coaxial with the transfer roller 4 provided on the apparatus main body 14 to rotate the transfer roller 4. The driving force to be transmitted is transmitted from the process cartridge B.

(Toner frame)
The toner frame will be described in detail with reference to FIGS. 3, 5, 7, 16, 20, and 21. 20 is a perspective view before the toner seal is welded, and FIG. 21 is a perspective view after the toner is filled.

  As shown in FIG. 3, the toner frame 11 is composed of two parts, an upper frame 11a and a lower frame 11b. As shown in FIG. 1, the upper frame 11a bulges upward so as to occupy the right space of the optical system 1 of the main body 14 of the image forming apparatus, and without increasing the size of the image forming apparatus A. The amount of toner in the process cartridge B is increased. As shown in FIGS. 3, 4, and 7, a recess 17 is provided from the outside at the center in the longitudinal direction of the upper frame 11 a, and has a handle function. Therefore, the operator holds the concave portion 17 of the upper frame body 11a and the lower side of the lower frame body 11b with hands. The longitudinal rib 11c provided on one side of the recess 17 and the lower side of the lower frame 11b serves as a slip stopper when the process cartridge B is provided. Then, as shown in FIG. 3, the flange 11a1 of the upper frame 11a is fitted to the flange 11b1 with a peripheral edge of the lower frame 11b, aligned at the welding surface U, and both the frames are melted by ultrasonic welding. The bodies 11a and 11b are integrated. However, the bonding method is not limited to ultrasonic welding, and may be performed by, for example, thermal welding, forced vibration, adhesion, or the like. When the two frames 11a and 11b are ultrasonically welded, both the frames 11a and 11b are supported by the flange 11b1 described above, and a step portion 11m is provided on the substantially upper surface of the flange 11b1 above the opening 11i. is there. A configuration for providing the stepped portion 11m will be described later.

  Prior to joining the frames 11a and 11b, the toner feeding member 9b is incorporated into the lower frame 11b. Further, as shown in FIG. 16, the coupling member 11e is assembled from the hole 11e1 on the side plate of the toner frame 11 so as to be engaged with the end of the toner feeding member 9b. The hole 11e1 is provided at one end in the longitudinal direction of the lower frame 11b. A toner filling port 11d having a substantially right triangle for filling the toner is provided on the same side as the hole 11e1. The edge of the toner filling port 11d has one side on the right side along the vicinity of the joint of the upper and lower toner frames 11a and 11b, one side in the vertical direction perpendicular to the one side, and a hypotenuse along the lower side of the lower frame 11b. . Therefore, the maximum size of the toner filling port 11d can be adopted. Therefore, the hole 11e1 and the toner filling port 11d are provided side by side. Furthermore, as shown in FIG. 20, in the longitudinal direction of the toner frame 11, an opening 11i of the toner frame 11 for sending toner from the toner frame 11 to the developing frame 12 is provided. A seal (described later) is welded so as to block 11i. Thereafter, toner is filled from the toner filling port 11d, and the toner filling port 11d is covered with a toner cap 11f as shown in FIG. The toner cap 11f is made of a material such as polyethylene or polypropylene, and is press-fitted or adhered to a toner filling port 11d provided in the toner frame 11 to be prevented from coming off. Further, the toner unit J is ultrasonically welded to a developing frame 12 which will be described later and becomes a developing unit D. However, the coupling method is not limited to ultrasonic welding, and may be performed by bonding or snap fitting using an elastic force.

  Further, as shown in FIG. 3, the slope K of the lower frame 11b of the toner frame 11 is an inclination angle θ that naturally falls when the toner is consumed, that is, the apparatus main body 14 with the apparatus main body 14 in a horizontal state. The angle θ formed by the inclined surface K of the process cartridge B attached to the horizontal line Z and the horizontal line Z is preferably about 65 °. Further, the lower frame 11b has a concave portion 11g on the lower side so as to escape the rotation region of the toner feeding member 9b. The rotation diameter of the toner feeding member 9b is about 37 mm. The recessed portion 11g may be recessed about 0 mm to 10 mm from the extended line of the slope K. If the concave portion 11g is above the inclined surface K, the toner that has naturally dropped from above the inclined surface K will not be sent to the developing frame 12 between the concave portion 11g and the inclined surface K. In this embodiment, the toner can be reliably sent from the toner frame 11 to the developing frame 12.

  The toner feeding member 9b is made of a rod-like iron material having a diameter of about 2 mm and has a crank shape. One of the journals 9b1 provided on one side as shown in FIG. It is pivotally attached to the hole 11r of the portion facing the opening 11i and the other is fixed to the coupling member 11e (the coupling portion is not visible in FIG. 20).

  As described above, by providing the concave portion 11g as the relief of 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.

    As shown in FIGS. 3, 20, and 22, an opening 11 i that feeds toner from the toner frame 11 to the developing frame 12 is provided at a joint portion between the toner frame 11 and the developing frame 12. A concave surface 11k is provided around the opening 11i. The groove 11n is provided in parallel on both edge sides directly in the longitudinal direction of the upper and lower flanges 11j, 11j1 of the concave surface 11k. The upper flange 11j of the concave surface 11k has a gate shape, and the lower flange 11j1 is in a crossing direction with respect to the concave surface 11k. As shown in FIG. 22, the bottom 11n2 of the groove 11n is in a position protruding outward (developing frame 12 side) from the concave surface 11k. Note that, as schematically shown in FIG. 39, the flange 11j of the opening 11i may be a single plane as a frame shape.

  As shown in FIG. 19, the surface of the developing frame 12 facing the toner frame 11 is a single plane 12u, and the plane 12u is parallel to the plane 12u at a position retreated from the plane 12u on the upper and lower sides and the longitudinal sides. A flange 12e is provided in a closed frame shape, and a protrusion 12v that fits in the groove 11n of the toner frame 11 is provided on the edge of the flange 12e along the longitudinal direction. A triangular protrusion 12v1 for ultrasonic welding is provided on the top surface of the protrusion 12v (see FIG. 22). Therefore, the toner frame 11 and the developing frame 12 after the respective parts are assembled are fitted with the groove 11n of the toner frame 11 and the protrusion 11v of the developing frame 12, and ultrasonic waves are formed along the longitudinal direction thereof. They are welded (details will be described later).

  As shown in FIG. 21, a cover film 51 that is easy to tear in the longitudinal direction is attached to the concave surface 11k so as to close the opening 11i of the toner frame 11. The cover film 51 is affixed to the toner frame 11 along the edges of the four sides of the opening 11i on the concave surface 11k. A tear tape 52 for tearing the cover film 51 is welded to the cover film 51 in order to open the opening 11i. The tear tape 52 is folded back at one end 52 b in the longitudinal direction of the opening 11 i and is attached to the end in the longitudinal direction of the flat surface facing the toner frame 11 of the developing frame 12, for example, an elastic material such as felt. A grip member 11t serving as a handle is attached to the end portion 52a which is pulled out through the seal material 54 (see FIG. 19) and the toner frame 11 and is pulled out (see FIGS. 6 and 20). FIG. 21). The handle member 11t is integrally formed with the toner frame 11, and the portion connected to the toner frame 11 is particularly thin and can be separated. The end of the tear tape 52 is attached to the handle member 11t. . A synthetic resin film tape 55 having a small friction coefficient is attached to the inside of the surface of the sealing material 54. Furthermore, an elastic seal material 56 is attached to the flat surface 12e at the end opposite to the position where the elastic seal material 54 is attached in the longitudinal direction (FIG. 19).

  The above-described elastic sealing materials 54 and 56 are affixed to the flange 12e in the full width in the short direction at both ends in the longitudinal direction of the flange 12e. The elastic sealing materials 54 and 56 coincide with the flanges 11j at both ends in the longitudinal direction of the concave surface 11k, and further overlap the ridges 12v over the entire width in the short direction of the flanges 11j.

    Further, when the toner frame 11 and the developing frame 12 are coupled, the flange 11j of the toner frame 11 is provided on the developing frame 12 in order to facilitate the alignment of the frames 11 and 12. A round hole 11r and a square hole 11q are provided to be fitted to the cylindrical dowel 12w1 and the square dowel 12w2. Here, the round hole 11r is closely fitted with the dowel 12w1, and the square hole 11q is closely engaged with the dowel 12w2 in the short direction and roughly in the longitudinal direction.

    When the toner frame 11 and the developing frame 12 are combined, the toner frame 11 and the developing frame 12 are assembled independently as a structured product. Thereafter, the cylindrical dowels 12w1 and the square dowels 12w2 for positioning the developing frame 12 are fitted into the positioning round holes 11r and the square holes 11q of the toner frame 11, respectively. Further, the protrusions 12v of the developing frame 12 are fitted into the grooves 11n of the toner frame 11, respectively. When the toner frame 11 and the developing frame 12 are pressed against each other, the sealing materials 54 and 56 are compressed in contact with the flanges 11j at both ends in the longitudinal direction of the toner frame 11, and the longitudinal direction of the flat surface 12u of the developing frame 12 is compressed. The ridges 12z serving as spacers integrally formed in the lateral direction on both sides approach the flange 11j of the toner frame 11. Here, the protrusions 12z are provided only on both sides of the tear tape 52 in the width direction (short direction) so as to allow the tear tape 52 to pass therethrough.

  In this state, the toner frame 11 and the developing frame 12 are pressed to apply ultrasonic vibration between the protrusion 12v and the groove 11n, and the triangular protrusion 12v1 is melted by frictional heat to be welded to the bottom of the groove 11n. As a result, the edge 11n1 of the groove 11n of the toner frame 11 and the spacer protrusion 12z of the developing frame 12 are in close contact with the mating member, and the developing frame 12 facing the concave surface 11k of the toner frame 11 is in contact. A space where the peripheral edge is in close contact is formed between the opposing planes 12u. The cover film 51 and the tear tape 52 are stored in this space.

  Further, in order to send out the toner stored in the toner frame 11 to the developing frame 12, the base side of the handle member 11t of the end portion 52a (FIG. 6) of the tear tape 52 protruding to the outside of the process cartridge B is toner. When the operator pulls the handle member 11t by hand after detaching or tearing the frame 11 from the frame 11, the cover film 51 is torn, the opening 11i of the toner frame 11 is opened, and the toner is removed from the toner frame 11. Can be sent to the developing frame 12. The elastic sealing materials 54 and 56 remain flat and have a hexagonal shape, and are deformed so that only the thickness is reduced at both ends in the longitudinal direction of the flange 11j of the toner frame 11, so that the sealing performance is good.

  Since the opposing surfaces of the toner frame 11 and the developing frame 12 are configured in this way, when the force for tearing the cover film 51 is applied to the tear tape 52, the tear tape 52 can be smoothly pulled out between the frames 11, 12.

  Further, when the toner frame 11 and the developing frame 12 are ultrasonically welded, frictional heat is generated, and the triangular protrusion 12v1 is melted by this frictional heat. Due to the frictional heat, the toner frame 11 and the developing frame 12 may be thermally deformed due to thermal stress. However, according to the present embodiment, the groove 11n of the toner frame 11 and the protrusion 12v of the developing frame 12 are fitted over almost the entire range in the longitudinal direction. The periphery of the welded portion is reinforced, and thermal deformation due to thermal stress hardly occurs.

  Examples of materials for forming the toner frame 11 and the developing frame 12 include plastics such as polystyrene, ABS resin acrylonitrile / butadiene / styrene copolymer, polycarbonate, polyethylene, and polypropylene.

  Here, FIG. 3 shows a side sectional view of the toner frame 11 used in the present embodiment. FIG. 3 shows the coupling surface JP where the toner frame 11 is coupled to the developing frame 12 in a substantially vertical direction.

  The toner frame 11 used in the present embodiment will be described in more detail. In order to efficiently drop the one-component toner stored in the toner container 11A in the direction of the opening 11i, two inclined surfaces K and L are provided. Both of the inclined surfaces K and L are provided in the full width of the toner frame 11 in the longitudinal direction. The inclined surface L is disposed above the opening 11i, and the inclined surface K is disposed on the back side of the opening 11i (the lateral direction of the toner frame 11). The slope L is formed in the upper frame 11a, and the slope K is constituted by the lower frame 11b. The inclined surface L is vertical in the state in which the process cartridge B is mounted on the apparatus main body 14 or the surface is downward from the vertical direction. The inclined surface K has an angle θ3 of about 20 degrees to 40 degrees with respect to a line m orthogonal to the joint surface JP of the toner frame body 11 and the developing frame body 12. In other words, in the present embodiment, when the lower frame 11b is coupled to the upper frame 11a, the shape of the upper frame 11a is defined so that the lower frame 11b can be installed at the installation angle. Therefore, according to the present embodiment, the toner container 11A containing the toner can efficiently supply the toner toward the opening 11i.

  Next, the developing frame will be described in more detail.

(Development frame)
The developing frame 12 will be described with reference to FIGS. 3, 14, 15, 16, 17, and 18. 14 is a perspective view showing a state in which each component is incorporated into the developing device frame 12, FIG. 15 is a perspective view showing a state in which the developing unit drive transmission unit DG is incorporated into the developing device frame 12, and FIG. FIG. 17 is a side view showing the developing unit drive transmission unit DG as viewed from the inside, and FIG. 18 is a perspective view showing the inside of the bearing box.

    As described above, the developing frame 12 incorporates the developing roller 9c, the developing blade 9d, the toner stirring member 9e, and the antenna rod 9h for detecting the remaining amount of toner.

  As shown in FIG. 14, the developing blade 9d is formed by fixing a urethane rubber 9d2 to a sheet metal 9d1 having a thickness of about 1 to 2 mm with hot melt, double-sided adhesive tape, etc. As a result, the amount of toner on the peripheral surface of the developing roller 9c is regulated. A dowel 12i1 (el), a square protrusion 12i3, and a screw hole 12i2 are provided at both ends in the longitudinal direction of a blade abutting flat surface 12i as a blade attachment portion provided in the developing device frame 12. Therefore, the hole 9d3 and the notch 9d5 provided in the sheet metal 9d1 are fitted into the dowel 12i1 and the protrusion 12i3, respectively. Thereafter, the screw hole 9d4 provided in the sheet metal 9d1 is inserted, the machine screw 9d6 is screwed into the screw hole 12i2, and the sheet metal 9d1 is fixed to the plane 12i. Note that an elastic seal member 12s such as a malt plane is attached to the developing frame 12 along the upper longitudinal direction of the sheet metal 9d1 in order to prevent leakage of toner to the outside. Further, the elastic seal member 12s1 is attached from both ends of the elastic seal member 12s to the arc surface 12j along the developing roller 9c. Further, a thin elastic seal member 12s2 that is in contact with the bus bar of the developing roller 9c is attached to the lower jaw portion 12h.

  Here, one end of the sheet metal 9d1 of the developing blade 9d is bent at approximately 90 ° to form a bent portion 9d1a.

  Next, the developing roller unit G will be described with reference to FIGS. The developing roller unit G includes (1) a developing roller 9c, and (2) a spacer roller 9i for making the distance between the peripheral surface of the developing roller 9c and the peripheral surface of the photosensitive drum 7 constant. Sleeve cap that is made of an insulating material and covers both ends of the developing roller 9c so that the aluminum Al cylindrical portion of the photosensitive drum 7 and the aluminum Al cylindrical portion of the developing roller 9c do not leak. Doubles as (3) A developing roller bearing 9j for supporting the developing roller 9c in a rotatable manner and positioning the developing roller 9c on the developing frame 12 (particularly enlarged in FIG. 14) (4) A helical tooth provided on the photosensitive drum 7 A developing roller gear 9k (helical gear) for rotating the developing roller 9c upon receiving driving from the drum gear 7b, and (5) a developing coil spring contact 9l (el) (one end) fitted to one end of the developing roller 9c. 18) and (6) provided inside the developing roller 9c and unitized by a magnet 9g for adhering the toner onto the peripheral surface of the developing roller 9c. In FIG. 14, the bearing box 9v is already attached to the developing roller unit G. However, the developing roller unit G uses the rear bearing box 9v passed to the side plates 12A and 12B of the developing frame 12 as the developing frame 12. Some are coupled to the bearing housing 9v when installed.

  In the developing roller unit G, as shown in FIG. 14, a metal flange 9p is fitted and fixed to one end of the developing roller 9c, and the developing roller gear mounting shaft portion 9p1 projects outward from the flange 9p. The mounting shaft portion 9p1 has a two-sided width portion in the cylindrical portion, and is fitted to the cylindrical portion with the two-sided width portion and is prevented from rotating, and a developing roller gear 9k made of synthetic resin is fitted. The developing roller gear 9k is a helical gear, and when rotating, the axial thrust is twisted so as to be directed toward the center of the developing roller 9c (see FIG. 38). Through this flange 9p, a D-cut partial circular shaft 9g1 of the magnet 9g protrudes to the outside. One of the circular circular shafts 9g1 is fitted into a developing holder 40 of a drive transmission unit DG, which will be described later, and is supported non-rotatingly. The developing roller bearing 9j described above is provided with a round hole having an anti-rotation projection 9j5 projecting inwardly, and a C-shaped bearing 9j4 is just fitted into the round hole, and the flange 9p is rotatably mounted on the bearing 9j4. It is mated. The developing roller bearing 9j is fitted into the slit 12f of the developing frame 12, and the protrusion 40f of the developing holder 40 is inserted into the hole 12g of the developing frame 12 and the hole 9j1 of the developing roller bearing 9j, and the developing holder 40 is developed. It is held by fixing to. The bearing 9j4 has a collar, and only the collar portion has a C shape. However, all axial cross sections may have a C shape. The hole into which the bearing 9j1 of the developing roller bearing 9j is fitted is a stepped hole, and the anti-rotation protrusion 9j5 is provided at the large diameter portion into which the collar of the bearing 9j4 is fitted. The bearing 9j and a bearing 9f described later are made of polyacetal, polyamide, or the like.

  Both ends of the magnet 9g through which the hollow cylindrical developing roller 9c is inserted protrude from both ends of the developing roller 9c, and the other circular shaft 9g1 is on the upper side of the drawing provided in the developing roller bearing box 9v shown in FIG. It fits into the invisible D-shaped support hole 9v3. A hollow journal 9w made of an insulating member is fitted and fixed to the inner periphery of the end of the developing roller 9c, and the reduced diameter cylindrical portion 9w1 integrated with the journal 9w is a developing coil spring contact 9l (el) that is electrically connected to the developing roller 9c. And the magnet 9g are insulated. The flanged bearing 9f is an insulator made of synthetic resin and is fitted into a bearing fitting hole 9v4 concentric with the magnet support hole 9v3. When the key portion 9f1 provided integrally with the bearing 9f is fitted into the key groove 9v5 provided in the bearing fitting hole 9v4, the bearing 9f is prevented from rotating.

  The bearing fitting hole 9v4 described above has a bottom, and an inner side end portion of the hollow disk-shaped developing bias contact 121 is formed on the bottom. When the developing roller 9c is assembled to the developing roller bearing box 9v, a metal developing coil spring contact 9l (el) is contracted and pressed against the developing bias contact 121. The developing bias contact 121 is bent from the outer diameter of the disk-shaped portion, fitted into the axial recess 9v6 of the bearing fitting hole 9v4, and a lead-out portion 121a passing through the outside of the bearing 9f, and a first lead-out portion Following 121a, the second lead-out part 121b fitted into the notch 9v7 at the end of the bearing fitting hole 9v4 and bent, the third lead-out part 121c bent from the second lead-out part 121b, The third lead-out part 121c has a fourth lead-out part 121d bent outward in the radial direction when viewed from the developing roller 9c, and the external contact part 121e is bent in the same direction from the fourth lead-out part 121d. In order to support such a developing bias contact 121, a supporting portion 9v8 protrudes toward the inner side in the longitudinal direction of the developing roller bearing box 9v, and the supporting portion 9v8 includes third and fourth lead-out portions 121c and 121d and an external portion. It contacts the contact part 121e. The second lead-out portion 121b has a stop hole 121f that is press-fitted into a dowel 9v9 that protrudes inward in the longitudinal direction on the back side of the developing roller bearing box 9v. The external contact portion 121e of the developing bias contact 121 comes into contact with a developing bias contact member 125 on the apparatus main body 14 described later when the process cartridge B is mounted on the apparatus main body 14. As a result, a developing bias is applied to the developing roller 9c.

  The developing roller bearing box 9v is fitted into the two cylindrical protrusions 9v1 provided in the developing roller bearing box 9v and the hole 12m provided at one end in the longitudinal direction of the developing frame 12 shown in FIG. Position with respect to the developing frame 12. Further, a small screw (not shown) is inserted into the female screw 12 c of the developing frame body 12 through the screw hole 9 v 2 of the developing roller bearing box 9 v to fix the developing roller bearing box 9 v to the developing frame body 12.

  Thus, in the present embodiment, the developing roller unit G is first assembled when the developing roller 9c is attached to the developing frame 12. Then, the assembled developing roller unit G is attached to the developing frame 12.

    The assembling of the developing roller unit G is performed in the following process. First, a magnet 9g is inserted into a developing roller 9c incorporating a flange 9p, a journal 9w and a developing coil spring contact 9l (el) are attached to one end of the developing roller 9c, a spacer roller 9i is attached to each of both ends, and further development is performed on the outside. Each of the roller bearings 9j is attached. Next, the developing roller gear 9k is attached to the developing roller gear mounting shaft portion 9p1 at one end of the developing roller 9c. Further, a missing circular shaft 9g1 of a magnet 9g having a D-cut at the tip is projected from both ends of the developing roller 9c to which the developing roller gear 9k is attached. In this way, the developing roller unit G is configured.

  Next, the antenna rod 9h for detecting the remaining amount of toner will be described. As shown in FIGS. 14 and 19, the antenna rod 9h has one end bent in a crank shape. The contact portion 9h1 (toner remaining amount detection contact 122) at one end is in contact with and electrically connected to a toner detection contact member 126 described later attached to the apparatus main body 14. To attach the antenna rod 9h to the developing frame 12, first, the tip of the antenna rod 9h is inserted through the through hole 12b provided in the side plate 12B of the developing frame 12. Then, the tip is supported in a hole (not shown) provided on the opposite side surface of the developing device frame 12. Thus, the antenna rod 9h is positioned and supported by the through hole 12b and the hole (not shown). Further, a seal member (not shown) (for example, a synthetic resin ring, felt, sponge, or the like) is inserted into the through hole 12b in order to prevent toner from entering.

  Note that when the developing roller bearing box 9v is attached to the developing frame 12, the arm portion of the crank-shaped contact portion 9h1 prevents the movement of the antenna rod 9h, and the antenna rod 9h moves outward. It is in a position not to escape.

    Here, the side plate 12A of the developing frame 12 on the side where the tip of the antenna rod 9h is inserted is extended to the side surface of the toner frame 11 when the toner frame 11 and the developing frame 12 are joined together, and below the toner. The toner cap 11f is partially covered so as to face the toner cap 11f provided on the frame 11b. Further, as shown in FIG. 16, the side plate 12A is provided with a hole 12x. In this hole 12x, a shaft coupling portion 9s1 (FIG. 15) of the toner feed gear 9s for transmitting a driving force to the toner feed member 9b. ) Is inserted. The toner feed gear 9s is connected to a coupling member 11e (see FIGS. 16 and 20) that engages with an end portion of the toner feed member 9b and is rotatably supported by the toner frame 11, so that the toner feed member A shaft coupling portion 9s1 for transmitting a driving force to 9b is integrally provided.

  As shown in FIG. 19, a toner stirring member 9e is rotatably supported on the developing device frame 12 in parallel with the antenna rod 9h. The toner agitating member 9e has a crank shape, and one journal is fitted in a bearing hole (not shown) of the side plate 12B, and the other journal integrally has a shaft portion rotatably supported by the side plate 12A shown in FIG. While being fitted into the toner stirring gear 9m, the crank arm is hooked on the notch of the shaft portion to transmit the rotation of the stirring gear 9m to the toner stirring member 9e.

  Next, transmission of driving force to the developing unit D will be described.

  As shown in FIG. 15, the support hole 40a of the developing holder 40 is fitted into the cut-out circular shaft 9g1 of the D-cut magnet 9g and is supported non-rotatingly. When the developing holder 40 is attached to the developing device frame 12, the developing roller gear 9k meshes with the gear 9q of the gear train GT, and the toner stirring gear 9m meshes with the small gear 9s2. As a result, the toner feeding gear 9s and the toner stirring gear 9m can receive driving force from the developing roller gear 9k.

  All the gears from the gear 9q to the toner feed gear 9s are idler gears. A gear 9q meshing with the developing roller gear 9k and a small gear 9q1 integrated with the gear 9q are rotatably supported by a dowel 40b integrated with the developing holder 40. The large gear 9r meshed with the small gear 9q1 and the small gear 9r1 integrated with the gear 9r are rotatably supported by a dowel 40c integrated with the developing holder 40. The small gear 9r1 meshes with the toner feed gear 9s. The toner feeding gear 9s is rotatably supported by a dowel 40d provided integrally with the developing holder 40. The toner feed gear 9s has a shaft coupling portion 9s1. The small gear 9s2 meshes with the toner feed gear 9s. The small gear 9s2 is rotatably supported by a dowel 40e provided integrally with the developing holder 40. The dowels 40b, 40c, 40d, and 40e have a diameter of about 5 to 6 mm and support each gear of the gear train GT.

  By adopting the above configuration, the gears constituting the gear train can be supported by the same member (developing holder 40 in the present embodiment). Therefore, regarding the assembly, the gear train GT can be partially assembled in the developing holder 40, and the assembly process can be dispersed and simplified. In other words, the antenna rod 9h and the toner stirring member 9e are assembled to the developing frame 12, and the developing roller unit G is assembled to the developing unit drive transmission unit DG and the gear box 9v is assembled to the developing frame 12 at the same time. Complete D.

  In FIG. 19, 12 p is an opening, which is provided along the longitudinal direction of the developing frame 12. The opening 12p faces the opening 11i of the toner frame 11 in a state where the toner frame 11 and the developing frame 12 are coupled. The toner contained in the toner frame 11 can be supplied to the developing roller 9c. Further, the stirring member 9e and the antenna rod 9h are attached along the full width in the longitudinal direction of the opening 12p.

  The material forming the developing frame 12 is the same as the material of the toner frame 11 described above.

(Configuration of electrical contacts)
Next, when the process cartridge B is mounted on the image forming apparatus main body 14, the connection and arrangement of contacts for electrically connecting the process cartridge B will be described with reference to FIGS. 8, 9, 11, 23, and 30. I will explain.

  The process cartridge B is provided with a plurality of electrical contacts as shown in FIG. Note that a drum grounding mechanism having a drum grounding contact 119 for releasing the electric charge staying on the photosensitive drum 7 to the apparatus main body 14 will be described later. That is, (1) a conductive charging bias contact 120 electrically connected to the charging roller shaft 8a in order to apply a charging bias from the apparatus main body 14 to the charging roller 8, and (2) development from the apparatus main body 14 to the developing roller 9c. Conductive developing bias contact 121 electrically connected to developing roller 9c to apply a bias, (3) Conductive toner remaining amount detection electrically connected to antenna rod 9h in order to detect the remaining amount of toner Four contacts 122 are provided so as to be exposed from the side surface and the bottom surface of the cartridge frame. The four contacts 119 to 122, except for the drum ground contact 119, have a distance at which no electrical leakage occurs between the contacts on the left side surface and bottom surface of the cartridge frame when viewed from the mounting direction of the process cartridge B. It is provided apart. The ground contact 119 and the charging bias contact 120 are provided in the cleaning unit C, and the development bias contact 121 and the toner remaining amount detection contact 122 are provided on the developing frame 12. The toner remaining amount detection contact 122 also serves as a process cartridge presence / absence detection contact for causing the apparatus main body 14 to detect that the process cartridge B is mounted on the apparatus main body 14.

  The charging bias contact 120 and the developing bias contact 121 are made of a conductive metal plate (for example, stainless steel, phosphor bronze) having a thickness of about 0.1 mm to 0.3 mm, which is stretched from the inside of the process cartridge. The charging bias contact 120 is exposed from the bottom surface on the counter driving side of the cleaning unit C, and the developing bias contact 121 and the toner remaining amount detection contact 122 are provided to be exposed from the bottom surface on the counter driving side of the developing unit D.

  Further details will be described.

  As described above, in this embodiment, a helical drum gear 7b is provided at one end in the axial direction of the photosensitive drum 7 as shown in FIG. The drum gear 7b meshes with the developing roller gear 9k and rotates the developing roller 9c. The drum gear 7b generates a thrust force (in the direction of the arrow d shown in FIG. 11) when rotating, and the drum gear 7b has a play in the longitudinal direction and is provided on the cleaning frame 13 with the drum gear 7b. The side end 7b1 of the drum gear 7b abuts against the inner end surface 38b of the bearing 38 fixed to the cleaning frame 13. As a result, the position of the photosensitive drum 7 in the axial direction is defined inside the process cartridge B. The drum shaft 7a enters the center of a drum cylinder 7d (made of aluminum in the present embodiment) covered with the photosensitive layer 7e.

  The charging bias contact 120 is provided in the vicinity of the portion of the cleaning frame 13 that supports the charging roller 8 (see FIG. 8). As shown in FIG. 23, the charging bias contact 120 is electrically connected to the shaft 8a of the charging roller 8 through a composite spring 8b that is in contact with the charging roller shaft 8a. The composite spring 8b is located at one end of the guide groove 13g and a charging roller bearing 8c that slides in a guide groove 13g on a line connecting the center of the charging roller 8 and the photosensitive drum 7 provided on the cleaning frame 13. An internal contact 8b2 that presses against the charging roller shaft 8a from the spring seat side winding portion of the compression coil spring portion 8b1 of the composite spring 8b that is compressed between the spring seats 120b is provided. As shown in FIG. 23, the charging bias contact 120 enters the cleaning frame 13 from the externally exposed portion 120a and is bent so as to cross the moving direction of the charging roller shaft 8a on one end side of the charging roller 8. The seat 120b is terminated.

  Next, the development bias contact 121 and the toner remaining amount detection contact 122 will be described. These two contacts 121 and 122 are provided on the bottom surface of the developing unit D provided on the same side as the one end 13k of the cleaning frame 13. The third lead-out portion of the developing bias contact 121, that is, the external contact portion 121e is disposed on the opposite side of the charging bias contact 120 with the spur gear 7n interposed therebetween. As described above, the developing bias contact 121 is electrically connected to the developing roller 9c via the developing coil spring contact 9l (el) which is electrically connected to the side end of the developing roller 9c (FIG. 18). reference).

  FIG. 38 schematically shows the relationship between the thrust generated in the drum gear 7 b and the developing roller gear 9 k and the developing bias contact 121. As already described, the photosensitive drum 7 is moved in the direction of the arrow d in FIG. 38 by driving, and the end surface on the drum gear 7b side rotates in contact with the end surface of the bearing 38 (see FIG. 32) not shown in FIG. The longitudinal position of the photosensitive drum 7 is constant. On the other hand, the developing roller gear 9k meshing with the drum gear 7b receives thrust in the direction of arrow e opposite to the arrow d, presses the developing coil spring contact 9l (el) pressing the developing bias contact 121, and the developing roller 9c and developing roller The pressing force in the direction of arrow f by the developing coil spring contact 9l acting between the bearing 9j is reduced. This ensures the contact between the developing coil spring contact 9l and the developing bias contact 121, reduces the frictional resistance between the end face of the developing roller 9c and the end face of the developing roller bearing 9j, and makes the developing roller 9c rotate smoothly.

  Further, the remaining toner detection contact 122 shown in FIG. 8 is provided to be exposed from the developing device frame 12 on the upstream side of the developing bias contact 121 with respect to the cartridge mounting direction (the arrow X direction in FIG. 9). 19, the toner remaining amount detection contact 122 is a conductive material provided on the developing frame 12 along the longitudinal direction of the developing roller 9c on the toner frame 11 side of the developing roller 9c. For example, it is part of a metal wire antenna rod 9h. As described above, the antenna rod 9h is provided at a position separated from the developing roller 9c by a certain distance over the entire length in the longitudinal direction of the developing roller 9c. When the process cartridge B is attached to the apparatus main body 14, it comes into contact with the toner detection contact member 126 on the apparatus main body 14 side. The electrostatic capacity between the antenna rod 9h and the developing roller 9c changes depending on the amount of toner existing between them. Thus, the remaining amount of toner is detected by detecting this change in capacitance as a potential difference change by a control unit (not shown) electrically connected to the toner detection contact member 126 of the apparatus main body 14. is there.

  Here, the toner remaining amount is a toner amount in which a toner amount existing between the developing roller 9c and the antenna rod 9h generates a predetermined electrostatic capacity. Thus, it can be detected that the remaining amount of toner in the toner container 11A has reached a predetermined amount. Accordingly, the controller provided in the apparatus main body 14 detects that the electrostatic capacity has reached the first predetermined value via the toner remaining amount detection contact 122, and the remaining amount of toner in the toner container 11A is reduced. It is determined that the predetermined amount has been reached. When the apparatus body 14 detects that the capacitance has reached the first predetermined value, the apparatus body 14 notifies the replacement of the process cartridge B (for example, blinking of a lamp, generation of sound by a buzzer). Further, the control unit detects that the process cartridge B is mounted on the apparatus main body 14 by detecting a second predetermined value in which the capacitance is smaller than the first predetermined value. The control unit does not start the image forming operation of the apparatus main body 14 unless it detects that the process cartridge B is mounted. That is, the image forming operation of the apparatus main body 14 is not started.

  Note that notification that the process cartridge is not installed may be performed (for example, blinking of a lamp, etc.).

  Next, the connection between the contact provided on the process cartridge B and the contact member provided on the apparatus main body 14 will be described.

  As shown in FIG. 9, on the inner surface of one side of the cartridge mounting space S of the image forming apparatus A, there are three pieces that can be connected to the respective contacts 120 to 122 when the process cartridge B is mounted. Contact member (charging contact member 124 electrically connected to charging bias contact 120, developing bias contact member 125 electrically connected to developing bias contact 121, toner detection contact member electrically connected to toner remaining amount detection contact 122 126).

  As shown in FIG. 9, the developing bias contact member 125, the toner detection contact member 126, and the charging contact member 124 are provided on the one side wall surface of the cartridge mounting space S near the guide portion 16a outside the guide portion 16a below the guide portion 16a. It is elastically provided downward and upward.

  Here, the positional relationship between each contact and the guide will be described.

  First, in FIG. 6 in which the process cartridge B is substantially horizontal, in the vertical direction, the toner remaining amount detecting contact 122 is at the lowest position, the developing bias contact 121 is above, the charging bias contact 120 is above, and the same is above the same. A detent guide 13bL and a cylindrical guide 13aL are arranged at a height. Further, in the cartridge mounting direction (arrow X direction), the toner remaining amount detection contact 122 is most upstream, the non-rotating guide 13bL and the developing bias contact 121 are downstream, the cylindrical guide 13aL is downstream, and the charging bias contact is downstream. 120 is arranged. With this arrangement, the charging bias contact 120 approaches the charging roller 8, the developing bias contact 121 approaches the developing roller 9c, and the remaining toner detection contact 122 approaches the antenna rod 9h. By doing so, it is possible to eliminate the winding of the electrodes on the process cartridge B side and the image forming apparatus main body 14 and shorten the distance between the contacts.

    Here, the size of the contact portion of each contact with the contact member is as follows. First, the charging bias contact 120 is about 10.0 mm in length and width, the development bias contact 121 is about 6.5 mm in length and about 7.5 mm in width, and the toner remaining amount detection contact 122 is 2 mm in diameter and about horizontal length. 18.0 mm. The charging bias contact 120 and the development bias contact 121 are rectangular. Here, the vertical direction of the contact is a direction according to the mounting direction X of the process cartridge B, and the horizontal direction is a horizontal direction perpendicular to the direction X.

  The toner remaining amount detection contact member 126 is a conductive leaf spring member provided near the guide portion 16a below the guide portion 16a. Further, the other contact members 124 and 125 are provided below the guide portion 16a and beside the guide 16a, and are attached so as to protrude upward from the holder 127 by a compression coil spring 129 shown in FIG. This will be described by taking the charging contact member 124 as an example. As shown in an enlarged view in a part of FIG. 30, the charging contact member 124 is attached in the holder 127 so as not to fall off and to protrude upward. The holder 127 is fixed to an electric board 128 attached to the apparatus main body 14, and each contact member and the wiring pattern are electrically connected by a conductive compression spring 129.

  When the process cartridge B is inserted into the image forming apparatus A and guided and mounted by the guide portion 16a, the contact members 124 to 126 are projected by spring force before reaching the predetermined mounting position. is there. At this time, each contact 120-122 of the process cartridge is not in contact with each contact member. As the process cartridge B is further inserted, the contact members 120 to 122 of the process cartridge B come into contact with the contact members 124 to 126, and the cylindrical guide 13aL of the process cartridge B is fitted into the positioning groove 16b. As a result, the contacts 120 to 122 retreat the contact members 124 to 126 against these elastic forces, respectively, and increase the contact pressure.

  As described above, in this embodiment, when the process cartridge B is guided by the guide member 16 and mounted at a predetermined mounting position, the respective contacts are securely connected to the respective contact members.

  That is, the charging bias contact 120 and the charging contact member 124 are electrically connected, and a high voltage (superimposition of AC voltage and DC voltage) is applied to the charging roller 8. Further, the developing bias contact 121 and the developing bias contact member 125 are electrically connected, and a high voltage is applied to the developing roller 9c. Further, the remaining toner detection contact 122 and the toner detection contact member 126 are electrically connected, and information corresponding to the electrostatic capacity between the contact 122 and the developing roller 9c is transmitted to the apparatus main body 14.

  Further, since each contact of the process cartridge B is arranged on one side of the cartridge frame as in the above-described embodiment, the mechanical mechanism member and the electrical wiring related members for the image forming apparatus main body 14 and the process cartridge B are mounted on the cartridge. The space S and the process cartridge B can be separately arranged on both sides, so that the number of assembling steps can be reduced and maintenance and inspection can be facilitated.

  When the process cartridge B is mounted on the image forming apparatus main body 14, as will be described later, the process cartridge side coupling device and the main body side coupling are coupled in conjunction with the closing operation of the opening / closing member 35. And the like can be rotated by receiving a drive from the apparatus main body 14.

  Alternatively, by arranging each contact as in the above-described embodiment, it is possible to shorten the winding of the electrode in the cartridge of each contact.

(Coupling and drive configuration)
Next, the configuration of a coupling unit that is a driving force transmission mechanism that transmits a driving force from the image forming apparatus main body 14 to the process cartridge B will be described.

  FIG. 11 is a longitudinal sectional view of the coupling portion showing a state in which the photosensitive drum 7 is attached to the process cartridge B. FIG.

  Now, as shown in FIG. 11, cartridge side coupling means is provided at one longitudinal end of the photosensitive drum 7 attached to the process cartridge B. In this coupling means, a coupling convex shaft 37 (cylindrical shaft portion) is provided on a drum flange 36 which is a coupling member fixed to one end portion of the photosensitive drum 7. A convex portion (connecting projection) 37a is formed on the distal end surface. The end surface of the convex portion 37 a is parallel to the end surface of the convex shaft 37. The convex shaft 37 is fitted into a bearing 38 and functions as a drum rotation shaft. In this embodiment, the drum flange 36, the coupling convex shaft 37, and the convex portion 37a are provided integrally. In order to transmit a driving force to the developing roller 9c in the process cartridge B, the drum flange 36 is integrally provided with a helical drum gear 7b as a gear portion. Therefore, as shown in FIG. 11, the drum flange 36 is an integrally molded product having a fitting portion 36b, a drum gear 7b, a convex shaft 37 and a convex portion 37a, and is a power transmission member having a function of transmitting a driving force. .

  The shape of the convex portion 37a is a twisted polygonal column, specifically, a column having a substantially equilateral triangular cross section, and is gradually twisted in the rotation direction in the axial direction. The concave portion (connecting hole) 39a fitted to the convex portion 37a is a hole having a polygonal cross section and being slightly twisted in the rotational direction in the axial direction. The convex portion 37a and the concave portion 39a have substantially the same twist pitch and are twisted in the same direction. The recess 39a has a substantially triangular cross section. And this recessed part 39a is provided in the coupling concave shaft 39b integral with the gear 43 provided in the apparatus main body 14. FIG. The coupling concave shaft 39b is provided in the apparatus main body 14 so as to be rotatable and axially movable as will be described later. Therefore, in the configuration of the present embodiment, the process cartridge B is mounted on the apparatus main body 14, the convex portion 37a and the concave portion 39a provided in the main body 14 are fitted, and the rotational force of the concave portion 39a is convex. When transmitted to the portion 37a, each ridge line of the convex portion 37a of the substantially regular triangular prism and the inner surface of the concave portion 39a are in contact with each other, so that the axes coincide with each other. For this reason, the diameter of the circumscribed circle of the coupling convex portion 37a is made larger than the inscribed circle of the coupling concave portion 39a and smaller than the circumscribed circle of the coupling concave portion 39a. Further, due to the twisted shape, a force acts in a direction in which the concave portion 39a pulls the convex portion 37a, and the convex portion end surface 37a1 contacts the bottom 39a1 of the concave portion 39a. Therefore, since the thrust generated in the coupling portion and the drum gear 7b works in the same direction as indicated by the arrow d, the photosensitive drum 7 integrated with the convex portion 37a is moved in the axial direction within the image forming apparatus main body 14. The position and the position in the radial direction are determined stably.

  In this embodiment, as viewed from the photosensitive drum 7, the twisting direction of the convex portion 37a is opposite to the rotation direction of the photosensitive drum 7, from the root of the convex portion 37a to the tip, or The twisting direction of the recess 39a is opposite to the inside from the inlet of the recess 39a, and the twisting direction of the drum gear 7b of the drum flange 36 is opposite to the twisting direction of the protrusion 37a.

  Here, the convex shaft 37 and the convex portion 37 a are arranged such that the drum flange 36 is positioned coaxially with the axis of the photosensitive drum 7 when the drum flange 36 is attached to one end of the photosensitive drum 7. Is provided. Reference numeral 36b denotes a fitting portion that is fitted to the inner surface of the drum cylinder 7d when the drum flange 36 is attached to the photosensitive drum 7. The drum flange 36 is attached to the photosensitive drum 7 by “caulking” or “adhesion”. The drum cylinder 7d is covered with a photosensitive layer 7e.

  As already described, the spur gear 7n is fixed to the other end of the photosensitive drum 7.

  The drum flange 36 and the spur gear 7n are made of a resin material such as polyacetal, polycarbonate, polyamide, and polybutylene terephthalate. However, other materials may be appropriately selected and used.

  In addition, a cylindrical convex portion 38a (cylindrical guide 13aR) concentric with the convex shaft 37 is integrated with a bearing 38 fixed to the cleaning frame 13 around the convex portion 37a of the coupling convex shaft 37 of the process cartridge B. (See FIG. 12). The convex portion 38a protects the convex portion 37a of the coupling convex shaft 37 from being damaged or deformed by an external force when the process cartridge B is attached or detached. Therefore, the projection 37a can be damaged to prevent rattling and vibration during the coupling drive.

  Further, the bearing 38 can also serve as a guide member when the process cartridge B is attached to and detached from 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 convex portion 38a of the bearing 38 abuts on the main body side guide portion 16c, and the convex portion 38a mounts the process cartridge B at the mounting position. Functions as a positioning guide 13aR, and facilitates attachment / detachment of the process cartridge B to / from the apparatus main body 14. Further, when the process cartridge B is mounted at the mounting position, the convex portion 38a is supported by the positioning groove 16d provided in the guide portion 16c.

  Further, there is a relationship as shown in FIG. 11 between the photosensitive drum 7, the drum flange 36, and the coupling convex shaft 37. That is, the outer diameter of the photosensitive drum 7 = H, the root diameter of the drum gear 7b = E, the bearing diameter of the photosensitive drum 7 (the outer diameter of the shaft coupling convex shaft 37, the inner diameter of the bearing 38) = F, the cup When the circumscribed circle diameter of the ring convex portion 37a = M and the fitting portion diameter (drum inner diameter) = N with the drum flange 36 of the photosensitive drum 7, there are relationships of H> F ≧ M and E> N.

  When H> F, the sliding load torque at the bearing portion can be reduced as compared with the case where the drum cylinder 7d is supported. However, since there is no undercut part, the mold configuration can be simplified.

  Furthermore, since the shape of the gear portion is provided on the left mold as viewed from the mounting direction of the process cartridge B due to the relationship of E> N, the right mold is simplified and the durability of the mold is improved. There is.

  On the other hand, the image forming apparatus main body 14 is provided with main body coupling means. In this main body coupling means, a coupling concave shaft 39b (cylindrical shape) is disposed at a position coinciding with the photosensitive drum rotation axis when the process cartridge B is inserted (see FIGS. 11 and 25). As shown in FIG. 11, the coupling concave shaft 39 b is a driving shaft integrated with a large gear 43 that is a driving rotating body that transmits the driving force of the motor 61 to the photosensitive drum 7. (The concave shaft 39b is the center of rotation of the large gear 43 and is provided so as to protrude from the side end of the large gear 43 (see FIGS. 25 and 26)). In the present embodiment, the large gear 43 and the coupling concave shaft 39b are formed by integral molding.

  The large gear 43 on the apparatus main body 14 side is a helical gear, and this helical gear is fixed to the shaft 61a of the motor 61 or meshed with a small helical gear 62 provided integrally therewith. In addition, when the driving force is transmitted from the small gear 62, it has teeth with a twist direction and an inclination angle that generate a thrust force that moves the concave shaft 39b in the direction of the convex shaft 37. Thus, when the motor 61 is driven during image formation, the concave shaft 39b is moved in the direction of the convex shaft 37 by the thrust, and the concave portion 39a and the convex portion 37a are engaged. The concave portion 39a is provided at the tip of the concave shaft 39b and at the rotation center of the concave shaft 39b.

  In this embodiment, the driving force is directly transmitted from the small gear 62 provided on the motor shaft 61a to the large gear 43. However, the gear train is used for deceleration and driving transmission, or the belt and pulley, friction. A roller pair, a timing belt and a pulley may be used.

  Next, a configuration for fitting the concave portion 39a and the convex portion 37a in conjunction with the closing operation of the opening / closing member 35 will be described with reference to FIGS. 24 and 27 to 29. FIG.

  As shown in FIG. 29, a side plate 67 is fixedly provided with a side plate 66 and a large gear 43 provided between the apparatus main body 14, and a cup integrally provided at the center of the large gear 43 on these side plates 66 and 67. The ring concave shaft 39b is rotatably supported. An outer cam 63 and an inner cam 64 are closely inserted between the large gear 43 and the side plate 66. 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 opposing surfaces in the axial direction of the outer cam 63 and the inner cam 64 are cam surfaces, and the cam surfaces are screw surfaces that contact each other around 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. 27, an arm 63a is provided in the radial direction from the outer periphery of the outer cam 63. The opening and closing member 35 is closed from the tip of the arm 63a and the fulcrum 35a of the opening and closing member 35. The position of the end of the opening / closing member 35 in the radial direction opposite to the end on the open side is coupled to one end of one link 65 by a pin 65a. The other end of the link 65 is coupled to the tip of the arm 63a by a pin 65b.

  FIG. 28 is a right side view of FIG. 27. When the opening / closing member 35 is closed, the link 65, the outer cam 63, etc. are in the positions shown in the figure, and the coupling convex portion 37a and the concave portion 39a are engaged with each other. The driving force 43 can be transmitted to the photosensitive drum 7. When the opening / closing member 35 is opened, the pin 65a is turned up around the fulcrum 35a, the arm 63a is pulled up via the link 65, the outer cam 63 rotates, and the outer cam 63 and the inner cam 64 face each other. The cam surface slides and the large gear 43 moves away from the photosensitive drum 7. At this time, the large gear 43 is pushed by the outer cam 63 and moves while pushing the compression coil spring 68 attached between the side plate 67 and the large gear 43, and the coupling recess 39a is moved to the cup as shown in FIG. The coupling is released away from the ring protrusion 37a, and the process cartridge B becomes detachable.

  Conversely, when the opening / closing member 35 is closed, the pin 65a connecting the opening / closing member 35 and the link 65 rotates around the fulcrum 35a and descends, the link 65 moves downward and pushes down the arm 63a. By rotating reversely and being pushed by the spring 68, the large gear 43 moves left from FIG. 29 to reach the position of FIG. 28, the large gear 43 is set again to the position of FIG. 28, and the coupling recess 39a is coupled. It fits into the convex part 37a and returns to a state where drive transmission is possible. By adopting such a configuration, it becomes possible to put the process cartridge B into a detachable and driveable state according to the opening / closing of the opening / closing member 35. When the opening / closing member 35 is closed, the outer cam 63 rotates in the reverse direction, and the large gear 43 moves leftward from FIG. 29, and the coupling concave shaft 39b and the end surface of the coupling convex shaft 37 abut against each other so that the coupling convex portion 37a. Even if the coupling recess 39a is not meshed (first rotational direction relative position), it is meshed immediately after the image forming apparatus A is started (second rotational direction position where relative rotation is impossible) as will be described later.

  Thus, in the present embodiment, when the process cartridge B is attached to or detached from the apparatus main body 14, the opening / closing member 35 is opened. Then, in conjunction with opening / closing of the opening / closing member 35, the coupling recess 39a moves in the horizontal direction (direction of arrow j). Therefore, when the process cartridge B is attached to and detached from the apparatus main body 14, the coupling (37a, 39a) between the process cartridge B and the apparatus main body 14 is not connected. They are not connected. Therefore, the process cartridge B can be smoothly attached to and detached from the apparatus main body 14. In the present embodiment, the coupling recess 39 a is pressed toward the process cartridge B by pressing the large gear 43 by the compression coil spring 68. Therefore, when the coupling convex portion 37a and the concave portion 39a mesh with each other, even if the coupling convex portion 37a and the concave portion 39a collide with each other and do not mesh well, the motor 61 rotates for the first time after the process cartridge B is mounted on the apparatus main body 14. As a result of the rotation of the coupling recess 39a, the two mesh instantly.

  Next, the shape of the convex part 37a and the concave part 39a which are engaging parts of the coupling means will be described.

  The coupling concave shaft 39b provided in the apparatus main body 14 can be moved in the axial direction as described above, but is attached 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 and the X direction (see FIG. 9) of the cartridge mounting direction. In the longitudinal direction, the process cartridge B is allowed to move slightly between the guide members 16R and 16L provided in the cartridge mounting space S.

  That is, when the process cartridge B is mounted on the apparatus main body 14, the cylindrical guide 13aL (see FIGS. 6, 7, and 9) formed on the flange 29 attached to the other longitudinal end of the cleaning frame 13 is the apparatus main body. 14 is a gear (not shown) that enters the positioning groove 16b (see FIG. 9) and is fitted and positioned without a gap, and a spur gear 7n fixed to the photosensitive drum 7 transmits a driving force to the transfer roller 4. Mesh. On the other hand, on one end side (drive side) of the photosensitive drum 7 in the longitudinal direction, a cylindrical guide 13aR provided in the cleaning frame 13 is supported by a positioning groove 16d provided in the apparatus main body 14.

  The cylindrical guide 13aR is supported by the positioning groove 16d of the apparatus main body 14, whereby the rotation shaft centers of the drum shaft 7a and the concave shaft 39b are supported within the concentricity φ2.00 mm, and the first in the coupling coupling process. The alignment operation is completed.

  When the opening / closing member 35 is closed, the coupling recess 39a moves horizontally and enters the projection 37a (see FIG. 28).

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

  First, when the drive motor 61 of the apparatus main body 14 rotates, the coupling concave shaft 39b moves in the direction of the coupling convex shaft 37 (the direction opposite to the arrow d in FIG. 11), and the phase of the coupling convex portion 37a and the concave portion 39a is shifted. At a certain point (in this embodiment, since the convex portion 37a and the concave portion 39a are substantially equilateral triangles, the phases of both are engaged every 120 °), the two are engaged and rotated from the apparatus main body 14 to the process cartridge B. Force is transmitted (from the state shown in FIG. 29 to the state shown in FIG. 28).

  In this coupling engagement, when the coupling convex portion 37a enters the concave portion 39a, there is a difference in the size of the substantially equilateral triangle, that is, the hole of the coupling concave portion 39a having a substantially equilateral triangle is the coupling convex portion. Since it is larger than the substantially equilateral triangle of 37a, it enters smoothly with a gap.

  In this embodiment, the lower limit value of the inscribed circle diameter of the convex triangle is set to φ8.0 mm from the required torsional rigidity, and the inscribed circle diameter of the φ8.5 mm concave triangle is set to φ9.5 mm and the gap is set to 0.5 mm. It was.

  On the other hand, in order to fit a pair of couplings with a small gap, it is necessary to maintain their concentricity before fitting.

    Therefore, in this embodiment, in order to maintain the concentricity φ1.0 mm necessary to guide the fitting with respect to the gap 0.5 mm, the protruding amount of the cylindrical bearing convex portion 38 is set to the coupling convex portion. Coupling of the convex portion 37 and the concave shaft 39a is performed by guiding the outer diameter portion of the concave shaft 39a with a plurality of projection-shaped guides 13aR4 provided in the bearing convex portion 38a. The concentricity before fitting is maintained at φ1.0 mm or less and the coupling fitting process is stabilized (second alignment action).

  When the coupling concave shaft 39b rotates with the coupling convex portion 37a entering the concave portion 39a during image formation, the inner surface of the coupling concave portion 39a and the three ridge lines of the substantially equilateral triangular column of the convex portion 37a are in contact with each other. The driving force is transmitted in contact. At this time, the coupling convex shaft 37 is instantaneously moved so as to coincide with the center of the concave shaft 39b so that the inner surface of the coupling concave portion 39a having a regular polygon shape and the ridge line of the convex portion 37a both come into contact with each other equally.

  With the above configuration, the coupling convex shaft 37 and the concave shaft 39b are automatically aligned when the motor 61 is driven. Further, when the driving force is transmitted to the photosensitive drum 7, a rotational force is generated in the process cartridge B, and a restricting contact portion 13j (FIG. 4, FIG. 4) provided on the upper surface of the cleaning frame body 13 of the process cartridge B by this rotational force. 5, 6, 7, and 30) increases the abutting force to the fixing member 25 (see FIGS. 9, 10, and 30) fixed to the image forming apparatus main body 14, and the image forming apparatus main body 14 The position of the process cartridge B with respect to is determined.

  In addition, when not driven (non-image formation), a gap is provided in the radial direction between the coupling convex portion 37a and the concave portion 39a, so that the couplings can be easily engaged and disengaged. Further, since the abutting force at the coupling engaging portion described above is stabilized during driving, rattling and vibration at this portion can be suppressed.

  In the present embodiment, the shape of the coupling convex portion and the concave portion is a substantially regular triangle, but it goes without saying that the same effect can be obtained if it is a substantially regular polygonal shape. In addition, positioning can be performed more accurately if it is a substantially regular polygonal shape, but may be a polygonal shape or the like as long as it is a shape that can be pulled and engaged without being limited thereto. Furthermore, a male screw having a large lead may be adopted as the coupling convex portion, and a female screw screwed into the male screw may be used as the coupling concave portion. In this case, a modified example of the triple triangular screw corresponds to the above-described coupling convex portion and concave portion.

  Furthermore, when the coupling convex part is compared with the concave part, the convex part is easily damaged in shape and inferior to the concave part in terms of strength. For this reason, in the present embodiment, a coupling convex portion is provided in the replaceable process cartridge B, and a coupling concave portion is provided in the image forming apparatus main body 14 that is required to have higher durability.

  FIG. 33 is a perspective view showing in detail the attachment relationship between the right guide member 13R and the cleaning frame 13, FIG. 34 is a longitudinal sectional view of the right guide member 13R attached to the cleaning frame 13, and FIG. It is a figure which shows a part of right side of this. FIG. 35 is a side view showing an outline of a mounting portion of the bearing 38 formed integrally with the right guide member 13R.

  The mounting of the right guide member 13R (38) with the bearing 38 integrated on the cleaning frame 13 shown schematically in FIG. 11 and the mounting of the unitized photosensitive drum 7 on the cleaning frame 13 are specifically described. I will explain it.

  As shown in FIGS. 33 and 34, a bearing 38 having a small diameter and being concentric with the cylindrical guide 13aR is integrally provided on the back surface of the right guide member 13R. The bearing 38 is connected to the end portion of the cylindrical bearing 38 by a disk member 13aR3 at an intermediate portion in the axial direction (longitudinal direction) of the cylindrical guide 38aR. A circular groove 38aR4 is formed between the bearing 38 and the cylindrical guide 13aR on the side of the cleaning frame 13 when viewed from the inside of the cleaning frame 13.

  As shown in FIGS. 33 and 35, a side surface of the cleaning frame 13 is provided with a bearing mounting hole 13h having a notch cylindrical shape, and the notch circle part 13h1 has a facing interval smaller than the diameter of the bearing mounting hole 13h. The interval is larger than the diameter of the coupling protrusion shaft 37. Further, since the coupling projecting shaft 37 is fitted to the bearing 38, it is spaced from the bearing mounting hole 13h. Positioning pins 13h2 that are integrally formed on the side surface of the cleaning frame 13 are closely fitted to the flange 13aR1 of the guide member 13R. As a result, the unitized photosensitive drum 7 can be attached to the cleaning frame 13 from the cross direction in the axial direction (longitudinal direction), and the right guide member 13R is attached to the cleaning frame 13 from the longitudinal direction. The position of the member 13R relative to the cleaning frame 13 is accurately determined.

  In order to attach the unitized photosensitive drum 7 to the cleaning frame 13, the photosensitive drum 7 is moved in the cross direction in the longitudinal direction as shown in FIG. 33 so that the drum gear 7 b is in the cleaning frame 13. Then, the coupling convex shaft 37 is inserted into the bearing mounting hole 13h through the cutout portion 13h1. In this state, the drum shaft 7a integrated with the left guide 13aL shown in FIG. 11 is passed through the side end 13k of the cleaning frame 13, and the drum shaft 7a is fitted to the spur gear 7n, and the flange 29 of the guide 13aL is fitted. Is inserted into the cleaning frame 13 and the guide 13aL is fixed to the cleaning frame 13 to support one end of the photosensitive drum 7.

    Next, the outer periphery of the bearing 38 integral with the right guide member 13R is fitted into the bearing mounting hole 13h, the inner periphery of the bearing 38 is fitted into the coupling convex shaft 37, and the positioning pin 13h2 of the cleaning frame 13 is moved to the right guide member. The flange 13aR1 of 13R is fitted into the hole, the small screw 13aR2 is screwed into the cleaning frame 13 through the flange 13aR1, and the right guide member 13R is fixed to the cleaning frame 13.

  As a result, the photosensitive drum 7 is fixed to the cleaning frame 13 accurately and firmly. Since the photosensitive drum 7 is attached to the cleaning frame 13 from the crossing direction with respect to the longitudinal direction, the photosensitive drum 7 does not have to be moved in the longitudinal direction, and the size of the cleaning frame 13 in the longitudinal direction can be reduced. For this reason, the image forming apparatus main body 14 can also be made small. The left cylindrical guide 13aL abuts and fixes a large flange 29 to the cleaning frame 13, and the drum shaft 7a integral with the flange 29 is closely fitted to the cleaning frame 13 and the right cylindrical guide 13aL. The guide 13aR is concentrically integrated with a bearing 38 that supports the photosensitive drum 7, and the bearing 38 is fitted in the bearing mounting hole 13h of the cleaning frame 13, so that the photosensitive drum 7 conveys the recording medium 2. It can arrange | position so that it may orthogonally cross with respect to a normal direction correctly.

  Since the left cylindrical guide 13aL is made of an integral metal with a large-area flange 29 and a drum shaft 7a projecting from the flange 29, the position of the drum shaft 7a is accurate and wear resistance is improved. The cylindrical guide 13aL is not worn even when the process cartridge B is repeatedly attached to and detached from the image forming apparatus main body 14. Then, as described above with respect to the electrical contact, the photosensitive drum 7 can be easily grounded. The cylindrical guide 13aL on the right side has a larger diameter than the bearing 38, and the bearing 38 and the cylindrical guide 13aR are coupled by a disk member 13aR3. Since the cylindrical guide 13aR is coupled to the flange 13aR1, the cylindrical guide 13aR, The bearings 38 are reinforced and stiffened together. Since the right cylindrical guide 13aR has a large diameter, it is durable against repeated attachment / detachment of the process cartridge B to / from the image forming apparatus main body 14 while being made of synthetic resin.

  36 and 37 are developed vertical sectional views showing another method of attaching the bearing 38 integral with the right guide member 13R to the cleaning frame 13. FIG.

    In particular, the drawing schematically shows the bearing 38 of the photosensitive drum 7 as a main part.

  As shown in FIG. 36, the outer edge of the bearing mounting hole 13h has a rib 13h3 in the circumferential direction, and the outer periphery of the rib 13h3 is a part of a cylinder. In this example, the circumference of the portion of the right cylindrical guide 13aR that extends beyond the disc member 13aR3 and reaches the flange 13aR1 is closely fitted to the outer circumference of the rib 13h3. The bearing mounting portion 13h of the bearing 38 and the outer periphery of the bearing 38 are loosely fitted. In this case, since the bearing mounting portion 13h is discontinuous at the missing circle portion 13h1, it is possible to prevent the missing circle portion 13h1 from opening and to reinforce.

  For the same purpose as described above, a plurality of restraining bosses 13h4 may be provided on the outer periphery of the rib 13h3 as shown in FIG.

  The constraining boss 13h4 has a circumscribed circle diameter of, for example, an IT tolerance class 9 and a concentricity within 0.01 mm with the inner diameter portion of the mounting hole 13h of the frame body when the molding die is manufactured.

  When the drum bearing 38 is attached to the cleaning frame 13, the mounting hole 13h of the cleaning frame 13 and the outer diameter portion of the bearing 38 are fitted, and the inner peripheral surface 13aR5 of the drum shaft 38 facing the outer diameter portion is Since the restraint boss 13h4 on the cleaning frame 13 side is restrained and fitted, misalignment at the time of assembling the bearing due to the opening of the notch 13h1 can be prevented.

(Combined structure of cleaning frame (also called drum frame) and developing frame)
As described above, the cleaning frame 13 incorporating the charging roller 8 and the cleaning unit 10 and the developing frame 12 incorporating the developing unit 9 are combined. Here, in general, this coupling portion requires at least the coupling of the drum frame 13 incorporating the electrophotographic photosensitive drum 7 and the developing frame 12 incorporating the developing means 9 as an aspect of the process cartridge B.

  The gist of the combined configuration of the drum frame 13 and the developing frame 12 will be described with reference to FIGS. 12, 13, and 32 as follows. In the following description, the right side and the left side refer to the case where the recording medium 2 is viewed from the upper side according to the transport direction.

  In a process cartridge that is detachable from the electrophotographic image forming apparatus main body 14, the electrophotographic photosensitive drum 7, developing means 9 for developing a latent image formed on the electrophotographic photosensitive drum 7, and the developing means A developing frame 12 that supports the drum 9, a drum frame 13 that supports the electrophotographic photosensitive drum 7, a toner frame 11 having the toner storage portion, one end in the longitudinal direction of the developing means 9, and the like. One end of the developing frame body 12 is attached to the end of the developing frame 12 above the developing means 9, and the other end is a compression coil spring 22a that abuts the drum frame 13, and the developing means 9 A first projecting portion (right arm portion 19) provided to project in a direction intersecting with the longitudinal direction of the developing means 9 at the developing frame body 12 on one end side and the other end side in the longitudinal direction. Second protrusion (Left arm portion 19), a first opening (right hole 20) provided in (first arm portion 19) in the first projecting portion, and second projecting portion (left arm portion). 19) and a second opening (the left hole 20) and one end in the longitudinal direction of the drum frame 13 above the electrophotographic photosensitive drum 7 and in the drum frame 13 portion. A first engaging portion (right concave portion 21) that engages with the first protruding portion (right arm portion 19), and the other end side in the longitudinal direction of the drum frame 13; , A second engaging portion (left concave portion) that engages with the second projecting portion (left arm portion 19) provided in the drum frame 13 portion above the electrophotographic photosensitive drum 7. 21) and a third opening (shown in FIG. 12 on the right side) provided in the first engagement part (right side recess 21). Hole 13e), a fourth opening (hole 13e shown in FIG. 12 on the left side) provided in the second engaging portion (left concave portion 21), the drum frame 13 and the developing frame 12. In order to connect, the first opening (right hole 20) is engaged with the first protrusion (right arm 19) and the first engagement portion (right recess 21). ) And the third opening (the right hole 13e), the first penetrating member (the coupling member 22 shown in FIG. 12 on the right side), and the drum frame 13 and the developing frame 12 are coupled to each other. In the state where the second protrusion (right arm 19) and the second engagement part (left recess 21) are engaged, the second opening (left hole 20) and the fourth And a second penetrating member (joining member 22 shown in FIG. 12 on the left side) penetrating through the opening (left hole 13e). Ridge B.

  The assembling method of the developing frame 12 and the drum frame 13 in such a configuration is as follows. A first engaging step for engaging the first projecting portion (right arm portion 19) of the developing frame body 12 and the drum frame body 13 with the first engaging portion (right recess portion 21); A second engaging step for engaging the second projecting portion (left arm portion 19) and the second engaging portion (left concave portion 21), the drum frame body 13, and the developing frame body 12. In order to couple, the first protrusion (right arm 19) and the first engagement part (right recess 21) are engaged with the first protrusion (right arm). The first opening (right hole 20) provided in the portion 19) and the third opening (right hole 13e) provided in the first engagement portion (right recess 21) In order to connect the developing frame 12 and the drum frame 13 to the first penetrating step of penetrating the penetrating member (right coupling member 22), The second protrusion provided on the second protrusion (left arm 19) in a state where the protruding portion (left arm 19) and the second engagement portion (left recess 21) are engaged. The second penetrating member (left coupling member 22) and the fourth opening (left hole 20) provided in the second engagement portion (left concave portion 21). ) Through the second penetrating step, the developing frame body 12 and the drum frame body 13 become a process cartridge B formed as an integral cartridge.

  As described above, the developing frame body 12 and the drum frame body 13 are assembled by simply engaging each other and allowing the coupling member 22 to pass through both of them. Only the frame 13 is pulled apart, and assembly and disassembly can be performed very easily.

In the above description, the developing unit 9 includes a developing roller 9c, and includes a first engaging step for engaging the first projecting portion with the first engaging portion, the second projecting portion, and the first projecting portion. The second engagement step for engaging the two engagement portions is performed simultaneously,
(1) The electrophotographic photosensitive drum 7 and the developing roller 9c are substantially parallel,
(2) Move the developing roller 9c along the periphery of the electrophotographic photosensitive drum 7,
(3) The developing frame 12 rotates with the movement of the developing roller 9c,
(4) The first and second protrusions (both arm portions 19) enter the first and second engaging portions (both concave portions 21) by the rotation of the developing frame 12, respectively.
(5) The first and second projecting portions (both arm portions 19) engage with the first and second engaging portions (both concave portions 21), respectively.
By doing so, the developing roller 9c can be rotated around the photosensitive drum 7 with the spacer rollers 9i in contact with the circumferential surfaces of both ends of the photosensitive drum 7, so that the arm portion 19 can approach the concave portion 21. Therefore, it is easy to match the hole 20 provided in the arm portion 19 of the developing frame 12 and the hole 13e provided on both sides of the concave portion 21 of the drum frame 13 with each other. Thus, the shapes of the arm portion 19 and the recess 21 can be determined.

  As described above, the development unit D in which the toner frame 11 and the development frame 12 are combined and the cleaning unit C in which the cleaning frame 13 and the charging roller 8 are combined are generally combined.

  Thus, when the developing frame 12 and the drum frame 13 are engaged, the opening of the first and second protrusions (hole 20) and the opening of the first and second engaging portions (hole 13e) are It is made to correspond substantially so that a penetration member (engagement member 22) can be penetrated.

  As shown in FIG. 32, the tip 19a of the arm portion 19 has an arc shape centered on the hole 20, and the bottom 21a of the recess 21 has an arc shape centered on the hole 13e. The radius of the arc of the tip 19a of the arm 19 is slightly smaller than the radius of the arc 21a at the bottom of the recess 21. This slightly smaller degree is obtained by inserting the coupling member 22 through the hole 13e of the drum frame (cleaning frame) 13 when the tip 19a of the arm 19 is abutted against the bottom 21a of the recess 21. The coupling member 22 whose end is chamfered into the hole 20 can be easily inserted, and when the coupling member 22 is inserted, there is an arc-shaped gap between the tip 19a of the arm portion 19 and the bottom 21a of the recess 21. g, and the arm portion 19 is rotatably supported by the coupling member 22. For the sake of explanation, the gap g is exaggerated, but the gap g is smaller than the end portion of the coupling member 22 or the chamfer dimension of the hole 20.

  As shown in FIG. 32, the developing frame 12 and the drum frame 13 are assembled while the hole 20 of the arm portion 19 defines either the locus RL1 or RL2 or the locus between the locus RL1 and RL2. At this time, the inner surface 20a of the upper wall of the recess 21 is continuously inclined so that the compression coil spring 22a is gradually compressed. That is, the shape is determined so that the distance from the inner surface 20a of the upper wall of the recess 21 facing the mounting portion of the compression coil spring 22a to the developing frame 12 at the time of assembly is gradually reduced. In this example, the upper end winding portion of the compression coil spring 22a is in contact with the inclined portion 20a1 of the inner surface 20a during assembly, and the compression coil spring 22a is inclined when the developing frame 12 and the drum frame 13 are combined. It contacts the spring seat 20a2 following 20a1. The compression coil spring 22a and the spring seat portion 20a2 intersect at a right angle.

  Thus, when the developing frame 12 and the drum frame 13 are assembled, it is not necessary to compress and insert the compression coil spring 22a separately. The body drum 7 is in pressure contact.

  The locus RL1 is an arc centered on the photosensitive drum 7, and the locus RL2 is an approximate straight line that gradually decreases as the distance from the inclined portion 20a1 increases from the right to the left in the drawing.

  As shown in FIG. 31, the compression coil spring 22 a is held by the developing device frame 12. FIG. 31 is a longitudinal sectional view according to the mounting direction X of the process cartridge B near the base of the arm portion 19 of the developing device frame 12. On the developing frame 12, a spring holding portion 12t is provided upward. The spring holding portion 12t has a cylindrical spring fixing portion 12k into which the inner periphery of the end portion of the compression coil spring 22a is press-fitted to the root side, and a diameter reduced from the fixing portion 12k and is inserted into the compression coil spring 22a halfway. 12n is provided. The height of the spring fixing portion 12k is required to be at least one turn of the end winding portion of the compression coil spring 22a, but two or more turns are desirable.

  As shown in FIG. 12, a partition wall 13t is provided between the outer wall 13s of the drum frame 13 and the inner side of the outer wall 13s, and a recess 21 is formed between these partitions.

  The inner rectangle in the longitudinal direction of the concave portion 21 shown in FIG. 12 is such that the opposing wall surfaces of the outer wall 13s and the partition wall 13t constituting the right concave portion 21 on the same side as the side where the drum gear 7b is provided are orthogonal to the longitudinal direction. The right arm portion 19 on the same side as the side where the developing roller gear 9k of the developing frame 12 is disposed is closely fitted between the opposing wall surfaces. On the other hand, the concave portion 21 of the left cleaning frame 13 on the same side as the side where the spur gear 7n is disposed and the arm portion 19 of the developing frame 12 inserted into the concave portion 21 are loosely fitted in the longitudinal direction. It has become.

  Therefore, the developing frame body 12 and the cleaning frame body 13 are accurately aligned in the longitudinal direction. This is because the dimension between the opposing wall surfaces of the concave portion 21 on one end side in the longitudinal direction can be easily obtained, and the width of the arm part 19 can be easily obtained. Even if a longitudinal dimensional difference due to thermal deformation occurs due to the temperature rise of the developing frame 12 and the cleaning frame 13, the portion that fits between the opposing walls of the concave portion 21 and the opposing wall of the arm portion 19 with a short size. This is because both have small dimensions, so that the thermal deformation difference is extremely small. Even if there is a difference in the dimensional change of the entire length in the longitudinal direction due to the thermal deformation of the developing frame 12 and the cleaning frame 13, the spur gear 7n side Since the recess 21 and the arm 19 fitted in the recess 21 are loosely fitted in the longitudinal direction, no stress is generated between the developing frame 12 and the cleaning frame 13 due to deformation due to thermal stress.

(Drum earth mechanism)
Next, a drum earth mechanism for releasing the electric charge staying on the photosensitive drum 7 to the apparatus main body 14 will be described.

  In this embodiment, the photosensitive drum 7 is grounded on the driving side.

  As shown in FIG. 11, a drum flange 34 is fitted and fixed to one end of the photosensitive drum 7 opposite to the driving side in the longitudinal direction of the drum cylinder 7d. The drum flange 34 is rotatably supported on a drum shaft 7 a fixed to the cleaning frame 13. The material of the drum shaft 7a in this example is not limited to metal and may be insulating synthetic resin.

  Further, a conductive member 119 is fitted through the center hole of the drum flange 36 fitted and fixed to the other end of the drum cylinder (cylindrical member) 7d so as to be movable in the axial direction. The conductive member 119 has a metal bar shape. One end thereof is fitted into a hole of a ground plate 118 which is a ground member provided so as to be in contact with the inner end surface 36c of the drum flange 36, and is fixed by caulking 119a (first contact portion). The ground plate 118 has a protrusion 118a at the end, and the protrusion 118a has a tip slightly facing the driving side and is elastically inserted into the inner surface 7d1 of the drum cylinder 7d (second contact portion). The ground plate 118 is made of metal and has an elastic force. Therefore, the conductive member 119 is movable in the longitudinal direction by the elastic force of the ground plate 118.

  41 is a longitudinal sectional view showing details of the ground contact in FIG. 40 in an enlarged manner, and FIG. 42 is a front view of the ground plate 118. As shown in FIG. 42, the ground plate 118 is a disc having a two-sided width and is provided with a groove 118b in parallel in an arc portion. The protrusion 118a between the grooves 118b is bent so as to be slightly laid at the root. Reference numeral 36d denotes a dowel projecting on the inner end surface 36c of the drum flange 36. A hole 118d provided in the ground plate 118 is fitted into the dowel 36d to prevent the ground plate 118 from rotating relative to the drum flange 36. . Further, a cutout hole 118c is provided between the projection 118a and the hole for the caulking 119a to increase the amount of deformation around the cutout hole 118c so that the ground plate 118 does not bend near the caulking 119a.

  Further, the ground contact 119 b at the other end of the conductive member 119 is located behind the end surface 37 a 1 of the convex portion 37 a provided at the tip of the coupling convex shaft 37. Since the ground contact 119b is located behind the convex end surface 17a1, the ground contact is used when the process cartridge B is attached to and detached from the apparatus main body 14 and when the process cartridge B removed from the apparatus main body 14 is handled. 119b is protected.

  As described above, when the ground contact 119b is pushed in the axial direction from the outside, the ground plate 118 is bent toward the inside of the drum cylinder 7d with both ends supported by the protrusions 118a, and the ground contact 119b Can be displaced in the axial direction.

  As shown in FIG. 43, the ground contact 119b is located on the same axis as the axis of the convex portion 37a (coupling convex shaft 37).

  As shown in FIG. 11, a main body ground contact member 123 is fitted and fixed at the center of a coupling concave shaft 39b provided in the apparatus main body. One end of the main body ground contact member 123 is a main body ground contact 123b that can come into contact with the ground contact 119b provided on the process cartridge B. The sliding terminal 123a at the other end is in pressure contact with a distal end portion of a leaf spring 117 fixed to a side plate 67 made of iron plate provided in the apparatus main body 14 with a machine screw 116. The main body ground contact 123b protrudes from the bottom surface 39a1 of the recess 39a to facilitate maintenance and inspection. The leaf spring 117 is a conductive material and is made of spring steel, stainless steel, phosphor bronze plate, beryllium, bronze plate or the like.

  The conductive member 119 is made of, for example, phosphor bronze, stainless steel, plated iron material, or the like. The ground contact member 123 can be made of the same material as the conductive member 119. When the leaf spring 117 is spring steel, the sliding terminal 123a is preferably phosphor bronze or beryllium bronze from the viewpoint of wear resistance.

  When the operator closes the opening / closing member 35 with the process cartridge B mounted on the apparatus main body 14, the coupling concave shaft 39b provided on the apparatus main body moves toward the convex portion 37a, and the concave portion 39a fits into the convex portion 37a. Match. Alternatively, the concave portion 39a is fitted to the convex portion 37a at the beginning of the rotation of the coupling concave shaft 39b. The ground contact 119b provided on the process cartridge B and the ground contact 123b provided on the apparatus main body 14 come into contact with each other before the projecting end surface 37a1 and the recess bottom surface 39a1 come into contact with each other. Further, the coupling concave shaft 39b and the ground contact member 123 are resisted against the spring force of the ground plate 118 by the spring force of the compression coil spring 68 (see FIG. 28) that biases the coupling concave shaft 39b in the direction of the convex shaft 37. It advances and the bottom face 39a1 of the coupling recessed part 39a and the edge part 37a1 of the convex part 37a contact. With respect to the movement of the sliding terminal 123a accompanying the forward movement of the coupling concave shaft 39b, the leaf spring 117 follows the sliding terminal 123a with a spring force.

  When the coupling concave shaft 39b starts to rotate, since the coupling concave shaft 39b has a forward end defined, the concave portion 39a generates a thrust in a direction to retract the convex portion 37a. As a result, the abutment between the projecting portion end 37a1 and the recessed portion end surface 39a1 is ensured, and a stable coupling connection is obtained. The main body ground contact member 123 rotates with the rotation of the coupling concave shaft 39b, and the sliding terminal 123a slides with the leaf spring 117. This sliding speed is slow, and a good contact state is maintained by sliding.

  Therefore, the electric charge staying on the photosensitive drum 7 can be released to the side plate 67 through the conductive member 119, the ground contact member 123, and the leaf spring 117.

  When the opening / closing member 35 is opened, the coupling concave shaft 39b moves in a direction away from the convex portion 37a. First, the end portion 37a1 of the convex portion 37a and the bottom surface 39a1 of the concave portion 39a are separated. Subsequently, the conductive member 119 moves for a short time due to the restoration of the ground plate 118, and the ground contact 119b provided in the process cartridge B follows the ground contact 123b provided in the apparatus main body 14, and then the ground contact 119b, 123b leaves. As the coupling concave shaft 39b retreats, the ground contact member 123 retreats while bending the sliding terminal 123a. Then, the recess 39a is retracted from the protrusion 37a and the fitting is released, so that the process cartridge B can be detached from the apparatus main body 14.

  In the embodiment described above, the process cartridge B is provided with the coupling convex shaft 37 having the convex portion 37a, and the apparatus main body 14 is provided with the coupling concave shaft 39b provided with the concave portion 39a that can be fitted to the convex portion 37a. It is. In the embodiment to be described next, the concavity 37c is provided at the center of the end surface 37b of the coupling convex shaft 37 as shown in FIGS. 44, 45 and 46, and the drive side coupling shaft 39b (no longer Since there is no concave portion, the convex concave portion 39c is provided at the center of the tip of the concave coupling shaft (the same reference numeral is used as the driving side coupling shaft).

  The concave portion 37c described above is a twisted hole having a substantially right-angle cross section, and the convex portion 39c is a twisted polygonal column having a shape obtained by twisting a substantially regular triangular column. The concave portion 37c is larger than the convex portion 39c. When the convex portion 39c is fitted into the concave portion 37c, each ridge line of the convex portion 39c is in contact with the inner surface of the concave portion 37c.

    The ground contact 123b on the apparatus main body 14 side is exposed at the center of the end surface 39c1 of the convex portion 39c, and the process cartridge B side ground terminal 119b is exposed on the bottom surface 37c1 of the concave portion 37c. As shown in FIG. 44, the ground contacts 119b and 123b are provided at the ends of the conductive member 119 and the ground contact member 123, respectively. In addition, what was demonstrated about FIGS. 40-43 etc. is used for another description.

(Relationship between coupling means and ground)
Since the coupling means described above is adapted to transmit a driving force by fitting a convex portion (protrusion) of a twisted polygonal column having the same number of angles to engage with a concave portion of a twisted hole having a polygonal cross section. The drive side pulls the body drum 7 in the axial direction. Therefore, it is effective to stably determine the position of the photosensitive drum 7 or the process cartridge B in the longitudinal direction.

  On the other hand, in order to press-contact the ground contacts 119b and 123b, the leaf spring 117 that pushes the coupling concave shaft 39b (drive side coupling shaft) in the axial direction is used, so that a coupling means that does not generate thrust can be employed.

  As such a coupling means, the convex portion 37a is a projection (not twisted) of a polygonal column (for example, a substantially regular triangular prism), and the concave portion 39a is a straight hole (not twisted) having a polygonal cross section (for example, a substantially triangular shape). The protrusion and the hole may be fitted. This produces a centering effect but no thrust. However, the ground contacts 119b and 123b can be pressed. On the other hand, as shown in FIG. 45, in the case where the relationship between the protrusion and the hole is reversed, the concave portion 37c is a straight hole having a polygonal cross section (for example, a substantially triangular shape) and the convex portion 39c is a polygonal column (for example, a substantially rectangular shape) Similarly, the projections of the triangular prisms have a centering action and do not generate thrust. However, the ground contacts 119b and 123b can be pressed.

  In the above description, the driving side member and the driven side member of any coupling means are both in a shape twisted in the axial direction or in a shape not twisted in the axial direction. However, depending on the mode when the process cartridge B is attached to the apparatus main body 14 and how the photosensitive drum 7 is attached to the process cartridge B, the process cartridge B having different specifications can be attached to and detached from the same apparatus main body 14.

  That is, it is assumed that the apparatus main body 14 includes a recess 39a having a twisted hole having a polygonal cross section. Here, when the process cartridge B is positioned in the longitudinal direction with respect to the apparatus main body 14 (for example, when a spring member is contracted on one side of the cartridge mounting portion of the cartridge frame and the apparatus main body 14 in the longitudinal direction, When the photosensitive drum 7 is attached to the cleaning frame 13 so as not to move in the axial direction), the convex portion 37a at the tip of the coupling convex shaft 37 can be a straight polygonal column fitted into the concave portion 39a. is there.

  When the apparatus main body 14 has a twisted polygonal column projection (projection), it is also possible to form a straight hole with a polygonal cross section that fits into the projection on the process cartridge B side.

  Next, the ground mechanism in the case of another supporting structure for supporting the photosensitive drum 7 on the cleaning frame 13 will be described. As shown in FIG. 47, drum flanges 34 and 36 are fixed to both ends of the photosensitive drum 7, and a coupling convex shaft 37 and a convex portion 37 a of a shaft coupling are provided on the drum flange 36. And inside this convex shaft 37, the end part 24a of the penetration shaft 24 made of iron is rotatably fitted so as to overlap the bearing 38. Further, the through shaft 24 is also rotatably fitted to the drum flange 34 on the opposite side. An earth plate 118 that conducts the drum cylinder 7 d and the through shaft 24 is fixed to the drum flange 34. A bearing 38 fixed and supported on the cleaning frame 13 supports the coupling convex shaft 17 in a rotatable manner. Furthermore, the opposite end 24b of the through shaft 24 is fixed to the cylindrical guide 13aL of the cleaning frame 13 by being press-fitted and supported. As a result, the photosensitive drum 7 is supported by the cleaning frame 13. The tip of the end portion 24a of the penetrating shaft 24 is reduced in diameter and penetrates the center of the convex portion 37a. Therefore, the tip of the through shaft 24 serves as a ground contact 119b, which is in pressure contact with the ground contact 123b provided on the apparatus main body 14.

  When the motor 61 rotates with the coupling convex portion 37a and the concave portion 39a engaged, the coupling convex shaft 37 rotates. The coupling convex shaft 37 and the drum flange 36 integrated therewith rotate on the through shaft 24 which is stationary. The drum flange 36 rotates together with the drum cylinder 7 d and the drum flange 34 that are integral with the drum flange 36. Further, the drum flange 34 rotates on the through shaft 24, and the ground contacts 119b and 123b slide.

  Since the ground plate 118 has one end pressed against the drum cylinder 7d and the other end pressed against the outer periphery of the through shaft 24, the ground plate 118 and the through shaft 24 slide by the rotation of the photosensitive drum 7.

  Next, an embodiment of another earth mechanism in another photoconductor drum support structure will be described with reference to FIG. Drum flanges 36 and 34 are fixed to both ends of the photosensitive drum 7, and a coupling convex shaft 37 and a convex portion 37 a of a shaft coupling member are integrally provided on the drum flange 36. An end portion 26 a of the iron penetration shaft 26 is press-fitted into the coupling convex shaft 37 so as to overlap the bearing 38. Further, the penetrating shaft 26 is also fitted to the drum flange 34 on the opposite side. Further, the bearing 38 is fixed to and supported by the cleaning frame 13 and rotatably supports the coupling convex shaft 37. Further, the opposite end 26b of the through shaft 26 is rotatably supported by a bearing 28 fitted and supported in a cylindrical guide 13aL provided in the cleaning frame 13. As a result, the photosensitive drum 7 is supported by the cleaning frame 13.

  Further, the ground plate 118 is fixed to the through shaft 26 and the drum cylinder 7d with protrusions (see 41 for the protrusion to be inserted into the drum cylinder 7d, FIG. 42, and the same shape for the protrusion to be inserted into the through shaft 26). It is.

  Next, another embodiment of the ground mechanism in the photosensitive drum support structure will be described with reference to FIG. Drum flanges 34 and 36 are fixed to both ends of the photosensitive drum 7. A through shaft 27 having a coupling convex portion 37a at the shaft end is fixed to one of the drum flanges 34 and 36 by press fitting or the like. Further, the enlarged diameter shaft portion 27 a at the end of the through shaft 27 is rotatably fitted to a bearing 38 supported by the cleaning frame body 13. Further, the other end 27 c of the through shaft 27 is rotatably fitted to a bearing 28 fixedly supported by the cleaning frame body 13. As described above, the photosensitive drum 7 is supported by the cleaning frame 13.

  In the above description, the through-shaft 27 and the drum cylinder 7d are inserted into the projections that are difficult to connect to the through-shaft 27 and the drum cylinder 7d (see FIGS. 41 and 42; A ground plate 118 made of spring steel. The through shaft 27 is made of iron or conductive resin.

  When the convex portion 37 a and the concave portion 39 a provided in the apparatus main body 14 are fitted, the convex portion end surface 37 a 1 (earth contact 119 b) comes into pressure contact with the main body ground contact 123.

    In the above description, the torsional direction of the recess 39a, that is, the hole (protrusion) is the direction in which it is screwed in the direction opposite to the rotational direction of the gear from the hole entrance to the back.

  The twist amount of the hole (projection) is a ratio of 1 ° to 15 ° in the rotation direction with respect to the axial length of 1 mm.

  In the present embodiment, the depth of the hole is about 4 mm and is twisted by about 30 °.

  In the above embodiment, an example of a twisted hole and a twisted polygonal column is shown as the coupling member, but the shape of the coupling member may be a twisted hole and a non-twisted polygonal column, for example. In this case, for example, an untwisted triangular prism as the polygonal column is fitted into the twisted hole, and when the hole rotates, the triangular column comes into contact with the inner surface of the hole at its root part, The position relative to is determined. Since the root portion is stronger than the other portions, the triangular prism as a protrusion is not deformed. In addition, the vicinity of the corner of the triangular prism and / or the inner surface of the hole is slightly locally deformed, and the vicinity of the corner is difficult to insert into the inner surface of the hole. Therefore, the connection between the recess and the hole becomes stronger. In addition, an untwisted polygonal column is easy to mold.

  Due to the alignment effect of the coupling, the rotation center of the sliding part of the earth contact part coincides with the earth contact part at the coupling center of the main body, thereby minimizing the sliding distance of the contact part and minimizing the sliding speed. Contact life and contact stabilization are achieved. Further, since the contact surface on the cartridge side is not exposed to the outside, it is possible to prevent contact failure due to touching with a hand or the like.

  50 and 51 show another embodiment of the ground mechanism.

  The earth contact member 123 provided in the apparatus main body 14 is loosely inserted through the center of the coupling concave shaft 39b and is not rotated. The rear end is fixed by caulking with the leaf spring 117. The other points are the same as in FIG.

  FIG. 51 shows another embodiment.

  The ground contact member 123 provided in the apparatus main body 14 is fixed to the coupling concave shaft 39b. A compression coil spring 117 is non-rotatably attached between the rear end of the ground contact member 123 and the bearing 116 that supports the coupling concave shaft 39b fixed to the side plate 67 of the apparatus main body 14. Therefore, the compression coil spring 117 and the ground contact member 123 slide. Also in this embodiment, the ground contacts 119b and 123b come into contact with each other to ground the photosensitive drum 7.

  In each of the above-described grounding embodiments, the ground contact 119 b is provided at the center of the drum flange 36. That is, the ground contact 119b is provided on the coaxial line with the axis of the drum flange 36. The conductive member 119 can be eliminated. That is, the drum flange 36 is brought into contact with the ground contact member 123 of the apparatus main body with the center portion being solid. The drum flange 36 itself is used as a conductive member. Suitable materials for the drum flange 36 include, for example, polyacetal containing a conductive filler, polyphenylene sulfone containing a conductive filler, polyamide containing a conductive filler, and the like. Less man-hours are required. Examples of the conductive filler include carbon filler, metal powder, and metal-coated glass fiber.

  FIG. 52 shows another embodiment.

  In this embodiment, a coupling component (drum flange 36) is molded in two colors. In other words, in the present embodiment, the projecting portion 37a and the connecting portion 36d connected to the projecting portion 37a (the portion marked with a dot in the drawing) are formed of the conductive material described above. Further, the gear 7b (helical gear) portion is formed of a material having high wear resistance (for example, boriacetal, polycarbonate, etc.). In addition, 36e is a fitting part and is a part fitted to the drum cylinder 7d. According to this embodiment, the charge of the photosensitive drum 7 can be released to the apparatus main body 14 through the connecting portion 36d and the convex portion 37a.

  FIG. 53 shows another embodiment of the coupling convex portion. A support shaft 37 a 5 is provided on the end surface of the convex shaft 37 on the same axis as the convex shaft 37. The arm 37a4 is projected radially from the support shaft 37a5, and a spherical contact portion 37a3 is provided at the tip thereof. Then, the spherical contact portion 37a3 comes into contact with the inner surface of the concave portion 39a and is coupled to transmit the driving force. Then, the ground contact 119b is exposed at the tip of the support shaft 37a5.

  FIG. 54 shows the arm 37a4 shown in FIG. 53 in a triangular plate. Also in the present embodiment, the ground contact 119b is arranged on the coaxial line with the convex shaft 37.

{Other Embodiments of Process Cartridge Grounding}
In this embodiment, the conductive member 119 is fixed to the coupling component (drum flange) 36. Details will be described below.

  First, the apparatus main body 14 side will be described. As shown in FIG. 55, the ground contact member 123 provided in the apparatus main body 14 is loosely inserted through the center of the coupling concave shaft 39b as in FIG. 50 and is not rotated. The rear end is fixed by a leaf spring 117 and a caulking 117a. The other configuration on the apparatus main body 14 side is the same as that in FIG.

  The main body ground contact 123b protrudes from the bottom surface 39a1 of the recess 39a to facilitate maintenance and inspection. The leaf spring 117 is a conductive material, and is made of spring steel, stainless steel, phosphor bronze plate, beryllium bronze plate, or the like.

  The conductive member 119 is made of, for example, phosphor bronze, stainless steel, plated steel, or the like. The ground contact member 123 can be made of the same material as the conductive member 119, but the material of the ground contact member 123 and the conductive member 119 can be used. The combinations are preferably different from each other.

  As shown in FIG. 55, the drum drum 34 is fitted and fixed to the photosensitive drum 7 on the side opposite to the driving side of the drum cylinder 7d. The drum flange 34 is rotatably supported by a drum shaft 7 a fixed to the cleaning frame 13. Since the drum shaft 7a of this example is not used for grounding, the material is not limited to metal and may be insulating synthetic resin.

    A fitting portion 36d of the drum flange 36 is fitted on the drive side of the drum cylinder 7d of the photosensitive drum 7, and the end of the drum cylinder 7d is directed toward the recess 36f provided in the fitting portion 36d as shown in FIG. 56a. The drum cylinder 7d and the drum flange 36 are fixed by caulking K. The drum flange 36 has a cylindrical hole 34a from the coupling convex portion 37a side, a hole 34b diameter-reduced by a step from the hole 34a, and a center hole formed from a narrow hole 34c that is remarkably enlarged from the diameter-reduced hole 34b. 34 is provided.

  A conductive member 119 is fitted by press-fitting so as not to move in the axial direction through the center hole 34 of the drum flange 36 fixed to the drive side. The conductive member 119 has a stepped rod shape in which the small diameter portion 119d is press-fitted into the hole 34b, and the large diameter portion 119c is fitted into the hole 34a with a gap. The small-diameter portion 119d end is fitted and fixed to a ground plate 118 provided so as to be in contact with the inner end surface 36c of the drum flange 36. The ground plate 118 has a protrusion 118a at its end, and the protrusion 118a is pointed toward the driving side and is elastically inserted into the inner surface 7d1 of the drum cylinder 7d.

  56a is an enlarged longitudinal sectional view showing details of the ground contact in FIG. FIG. 57 is a front view of the ground plate 118. As shown in FIG. 57, the earth plate 118 has a disk shape and grooves 118b are formed in parallel on the circular arc portions on both sides of the diameter, and the protrusion 118a between the grooves 118b has a tip 118a1 bent toward the driving side. ing. The tip 118a1 has two chevron-shaped protrusions, and these protrusions are recessed from the inner surface 7d1 of the drum cylinder 7d. Reference numeral 36d denotes a dowel projecting from the inner end face 36c of the drum flange 36, which is a stopper for rotating the ground plate 118 with respect to the drum flange 36 with the ground plate 118 fitted therein. The tip of the dowel 36d is semi-melted and expanded in diameter, and the drum flange 36 and the ground plate 118 are fixed. The enlarged dowel 36d prevents the ground plate 118 from being separated from the drum flange 36 when the ground contact 119 is assembled.

  The ground terminal 119 b at the other end of the ground contact 119 is in a position that is recessed from the convex portion 37 a 1 provided at the tip of the coupling convex shaft 37. Since the ground terminal 119b is recessed from the convex end surface 17a1, the ground terminal 119b is protected when the process cartridge B is attached to and detached from the apparatus main body 14 and when the process cartridge B removed from the apparatus main body 14 is handled. The

  As shown in FIG. 43, the ground terminal 119b appears in the axial direction passing through the axial center of the end surface 37a1 of the convex portion 37a.

  Next, the relationship between the ground plate 118 and the shape on the inner end face 36c side of the drum flange 36 will be described. As shown in FIG. 56a, the inner end face 36c of the drum flange 36 is provided with a groove 36g in the diametrical direction. The position of the groove 36g coincides with the protrusion 118a of the ground plate 118 so that the bent end 118a1 of the protrusion 118a does not interfere with the inner surface 7d1 of the drum cylinder 7d. The ground plate 118 has a disk shape except for the protrusion 118a. The diameter of the disk is slightly smaller than the inner diameter of the drum cylinder 7d, but the protrusion 118a protrudes outward from the disk. The center hole 118d of the ground plate 118 into which the conductive member 119 is fitted has an H shape as shown in FIG. The opposing edge 118d1 of the line connecting the left and right of the H-shape is bent obliquely toward the non-driving side as shown in FIG. The distance between the opposing edges 118d1 is smaller than the diameter of the small diameter portion 119d of the ground contact 119.

  Next, the positional relationship between the protrusion 118a of the ground plate 118, the hole 118c into which the dowel 36h is fitted, and the ground contact stop hole 118d will be described. The protrusion 118a and the dowel hole 118c are provided at equal distances from the center on lines A and B passing through the center of the ground plate 118, respectively.

    Lines A and B intersect, and in this example, θ is about 30 degrees. The ground contact stop hole 118d is on a line C having the opposite edge 118d1 orthogonal to the line B and passing through the center of the ground plate 118, and the distance from the center of the ground plate 118 to the opposite edge 118d1 is equal.

  Here, the dowel hole 118c of the ground plate 118 is fitted into the dowel 36h of the drum flange 36, the ground plate 118 is brought into contact with the inner end surface 36c of the drum flange 36, the dowel 36d is heated, and the head is half melted. As shown in FIG. 56a, the diameter is expanded as a hemisphere. Here, when naturally cooled, the drum flange 36 and the ground plate 118 are fixed. Then, the conductive member 119 is inserted into the center hole 34 of the drum flange 36 in the direction of the arrow Y as shown in FIG. 56a. First, the small diameter portion 119d of the conductive member 119 is press-fitted into the small diameter hole 34b of the drum flange 36. Next, the small-diameter portion 119d of the conductive member 119 pushes the opposing edge 118d1 into the ground contact stop hole 118d at the center of the ground plate 118, and is fitted. Further, the large diameter portion 119c of the conductive member 119 is in contact with the step portion of the center hole 34 of the drum flange 36, and the axial position of the conductive member 119 relative to the drum flange 36 is determined. The ground contact point 119b is at a position retracted into the center hole 34 by a predetermined depth from the end surface 37a1 of the coupling protrusion 37a.

  Thus, the drum flange 36, the ground plate 118, and the conductive member 119 are unitized as coupling parts. Then, the fitting portion 36d of the drum flange 36 and the drum cylinder 7d are fitted, and the end of the drum cylinder 7d is fixed by caulking K toward the recess 36f of the drum flange 36. A perspective view of the coupling component C shown in FIG. 56a is shown in FIGS. 56b and 56c.

  The contact / separation of the cartridge ground contact 119b and the main body ground contact 123b in this embodiment is as follows. When the main body gear 43 is driven in the state of FIG. 55, the photosensitive drum 7 rotates. The drum flange 36 having the drum gear 7b rotates together with the conductive member 119 (earth contact 119b). Since the drum gear 7b is a helical gear, it receives a thrust force in the direction d in FIG. As described above, the coupling convex portion 37a and the coupling concave portion 39a are attracted to each other in the axial direction, and the bottom surface 39a1 of the coupling concave portion 39a and the end surface 37a1 of the coupling convex portion 37a are in pressure contact. As already described, since the coupling recess 39a is in a fixed position advanced by closing the opening / closing member 35 of the apparatus main body 14, the axial position of the photosensitive drum 7 during image formation is fixed.

  As described above, the leaf spring 117 presses the ground contact member 123 with the spring force against the ground contact 119 of the process cartridge B in the direction opposite to the arrow d in the axial direction. Since the thrust for pulling the portion 37a toward the coupling recess 39a and the thrust of the drum gear 7b are set to be weaker, the spring force of the leaf spring 117 does not impair the positioning of the photosensitive drum 7 in the axial direction.

  The ground contact member 123 is fixed to the leaf spring 117 and is pressed against the ground contact 119 by the spring force of the leaf spring 117. Therefore, the ground contact 119b of the conductive member 119 and the contact 123b of the ground contact member 123 are in pressure contact and slide.

  When removing the process cartridge B from the apparatus main body 14, the coupling concave shaft 39 b moves backward from the coupling convex portion 37 a together with the large gear 43. At the beginning of the retraction of the coupling concave shaft 39b, the ground contact member 123 is in pressure contact with the ground contact 119b of the process cartridge B by the spring force of the leaf spring 117. Then, after the rear end of the coupling concave shaft 39b comes into contact with the leaf spring 117, the leaf spring 117 is deformed to the left in FIG. 55 against the spring force by the retreat of the coupling concave shaft 39b. Then, the ground contact member 123 is retracted, the ground contact 119b is separated from the main body ground contact 123b, and the ground contact member 123 is retracted. Next, the coupling concave portion 39a comes off in the axial direction from the coupling convex portion 37a. Furthermore, it surrounds the coupling convex part 37a of the bearing 38, comes to a position away from the cylindrical convex part 38a in the axial direction, and stops at a fixed position. In this way, the operation is performed by the interlocking device of the opening / closing member 35 and the coupling concave shaft 39b shown in FIGS. 27 to 29, for example.

  As described above, the process cartridge B is attached and detached with the coupling concave shaft 39b retracted. When the opening / closing member 35 is closed after the process cartridge B is mounted on the apparatus main body 14, the coupling concave shaft 35b moves forward along the ground contact member 123, and the coupling concave portion 39a is fitted to the coupling convex portion 37a. When the coupling recess 39a deepens the fitting to the coupling protrusion 37a, the main body ground contact 123b comes into contact with the cartridge ground contact 119b. The ground contact member 123 is stopped by the conductive member 119 while being pushed by the leaf spring 117. As the coupling concave shaft 39b further advances, the bottom surface 39a1 of the coupling concave portion 39a contacts the end surface 37a1 of the coupling convex portion 37a.

  In the above, the conductive member 119 and the ground contact member 123 are made of the materials already described. In this embodiment, since the opposite edge 118d of the ground contact stop hole 118d at the center of the ground plate 118 is inserted into the conductive member 119, the material of the ground plate 118 is higher than that of the conductive member 119, for example, Spring steel, plated spring steel, etc. are desirable.

  According to this embodiment, the conductive member 119 is fixed to the drum flange 36. Therefore, the conductive member 119 can be attached simply by being inserted into the ground contact stop hole 118d of the ground plate 118 to prevent it from coming off. Even if the press-fitting of the ground contact 119 into the center hole 34 of the drum flange 36 is loosened, the conductive member 119 does not come out of the drum flange 36. Since the center hole 34 of the drum flange 36 has a step portion against which the step portion of the conductive member 119 abuts, the conductive member 119 is accurately positioned in the axial direction of the drum flange 36.

  The ground plate 118 is in contact with the inner end surface 36c of the drum flange 36 and is fixed by a dowel 36d, and a protrusion 118a inclined toward the driving side is recessed from the inner surface 7d1 of the drum cylinder 7d. Accordingly, it is possible to prevent the drum flange 36 from coming out of the drum cylinder 7d. Further, the drum cylinder 7d is prevented from rotating with respect to the drum flange 36. Since the end of the drum cylinder 7d is caulked toward the recess 36f of the drum flange 36, the drum flange 36 is firmly fixed to the drum cylinder 7d.

  In the embodiment in which the conductive member 119 is fixed to the drum flange 36, the center hole of the coupling concave shaft 39b is, for example, a rectangular shape, and the ground contact member 123 fitted into the center hole is just fitted into the square hole. Axial movement is possible. The leaf spring 117 and the ground contact member 123 may be slid using the rear end of the leaf spring 117 and the ground contact member as a contact 123a. In this case, since the ground contact member 123 is retracted when the coupling concave shaft 39b is retracted, the coupling to the ground contact member 123 is performed at a position between the coupling concave shaft 39b and the leaf spring 117 as shown in FIG. A collar 123c that contacts when the concave shaft 39b moves backward is provided.

    In each of the above embodiments, the leaf spring 117 is used to bias the earth contact member 123 toward the earth contact 119b. However, as shown in FIG. 63, a compression coil spring 130 may be used. In the present embodiment, a compression coil spring 130 is attached between the follower of the ground contact member 123 and the fixed side plate 131. Therefore, the ground contact member 123 is pressed against the cartridge ground contact 119b by the elastic force of the coil spring 130. Reference numeral 132 denotes a screw, and the fixed side plate 131 is attached to the main body side plate 67. 25, FIG. 26, FIG. 28 and FIG. 29 show the embodiment using the compression coil spring 130, but other embodiments may be used.

  In addition, you may implement each embodiment mentioned above combining suitably. For example, the embodiment shown in FIGS. 56 and 57 may be implemented in combination with the embodiment shown in FIG. 11 or 61, for example. Similarly, for example, the embodiment shown in FIGS. 53 and 54 may be combined with the embodiment shown in FIG. 11 or 61, for example. For example, the embodiment shown in FIG. 50 may be implemented in combination with, for example, FIG. 55, FIG. 60, or FIG. Further, although the embodiment shown in FIG. 52 has been described by taking the convex portion as an example, it may of course be a concave portion. The embodiment shown in FIG. 52 can also be implemented in combination with the apparatus main body shown in FIGS. 11, 55, 60 and 61, for example.

As explained above, according to the embodiment described above,
To transmit power from the image forming apparatus main body to the process cartridge, either one of the image forming apparatus main body or the process cartridge is provided with a hole, and the other is provided with a protrusion that fits into the hole. In addition, by providing a ground contact in the inside of the hole and the projection when the hole and the projection are fitted, it is possible to ground the rotating portion at the end of the electrophotographic photosensitive drum.

  Further, since this ground contact has an elastic force, a reliable connection is possible.

  By making the hole and the protrusion in the above-described twisted shape, the connection of the ground contact is further assisted and the connection is stabilized.

  The holes and protrusions have a self-aligning action by making the cross-sections substantially triangular. Further, since the hole and the protrusion can be loosely fitted, the engagement and disengagement are easy.

  The process cartridge B shown in the above-described embodiment has exemplified the case of forming a single color image. However, the process cartridge according to the present invention is provided with a plurality of developing means, and a plurality of color images (for example, two-color images, three-color images, or The present invention can also be suitably applied to a cartridge that forms a full color or the like.

  Further, the electrophotographic photosensitive member is not limited to the photosensitive drum 7 and includes, for example, the following. First, a photoconductor is used as the photoreceptor, and examples of the photoconductor include amorphous silicon, amorphous selenium, zinc oxide, titanium oxide, and organic photoconductor (OPC). As the shape for mounting the photoconductor, for example, a drum shape or a belt shape is used. For example, in the case of a drum type photoconductor, a photoconductor is vapor-deposited or coated on a cylinder such as an amyl alloy. It is the one that has been crafted.

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

  In addition, the so-called contact charging method is used in the above-described embodiment for the configuration of the charging means. However, as another configuration, a metal shield such as aluminum is provided around three sides of a tungsten wire that has been conventionally used, and the tungsten wire is attached to the tungsten wire. Of course, it is also possible to use a configuration in which positive or negative ions generated by applying a high voltage are moved to the surface of the photosensitive drum and the surface of the drum is uniformly charged.

As described above, according to the present embodiment,
Power transmission from the image forming apparatus main body to the process cartridge is provided with a hole in one of the image forming apparatus main body and the process cartridge, and the other is provided with a protrusion that fits into this hole. By providing a ground contact to be connected when each is fitted, it is possible to ground the rotating portion at the end of the electrophotographic photosensitive drum.

  Further, since this ground contact has an elastic force, a reliable connection is possible.

  By making the holes and protrusions in the above-described twisted shape, the connection of the ground contact is further assisted and the connection is stabilized.

    The holes and protrusions have a substantially equilateral triangle in cross section, thereby providing a self-aligning action. Further, since the hole and the protrusion can be loosely fitted, the engagement and disengagement are easy.

Each drawing shows an embodiment of the present invention,
1 is a longitudinal sectional view of an electrophotographic image forming apparatus. It is an external appearance perspective view of the apparatus shown in FIG. It is a longitudinal cross-sectional view of a process cartridge. FIG. 4 is an external perspective view of the process cartridge shown in FIG. 3 as viewed from the upper right side. FIG. 4 is a right side view of the process cartridge shown in FIG. 3. FIG. 4 is a left side view of the process cartridge shown in FIG. 3. FIG. 4 is an external perspective view of the process cartridge shown in FIG. 3 as viewed from the upper left side. FIG. 4 is an external perspective view showing the lower left side of the process cartridge shown in FIG. 3. FIG. 3 is an external perspective view of a process cartridge mounting portion of the apparatus main body. FIG. 3 is an external perspective view of a process cartridge mounting portion of the apparatus main body. It is a longitudinal cross-sectional view of a photosensitive drum and its driving device. It is a perspective view of a cleaning unit. It is a perspective view of a developing unit. It is a partial exploded perspective view of a developing unit. It is a perspective view which looks at the back part of a development holder. FIG. 3 is a side view of a side plate of a developing frame and a toner frame. FIG. 16 is a side view of the developing holder portion of FIG. 15 viewed from the inside to the outside. It is a perspective view of a developing roller bearing box. It is a perspective view of a developing device frame. 3 is a perspective view of a toner frame. FIG. 3 is a perspective view of a toner frame. FIG. FIG. 22 is a longitudinal sectional view of the toner seal portion in FIG. 21. It is a longitudinal cross-sectional view which shows the support apparatus of a charging roller part. 2 is a schematic longitudinal sectional view showing a drive system of the electrophotographic image forming apparatus main body. FIG. It is a perspective view of the coupling provided in the apparatus main body and the coupling provided in the process cartridge. It is a perspective view of the coupling provided in the apparatus main body and the coupling provided in the process cartridge. It is sectional drawing showing the structure of the opening / closing member and coupling part of an apparatus main body. FIG. 6 is a front view illustrating a configuration around a coupling concave axis when the process cartridge of the apparatus main body is driven. FIG. 6 is a front view illustrating a configuration around a coupling concave axis when the process cartridge of the apparatus main body is attached / detached. It is a longitudinal cross-sectional view which shows the electrical contact relationship at the time of process cartridge attachment or detachment to an apparatus main body. It is a side view which shows the attaching part of a compression coil spring. It is a longitudinal cross-sectional view which shows the coupling | bond part of a drum frame and a developing device frame. It is a perspective view which shows the attachment part to the cleaning frame of a photosensitive drum. It is a longitudinal cross-sectional view which shows a drum bearing part. It is a side view which shows the external shape of a drum bearing part. It is an expanded sectional view showing other embodiments of a drum bearing part. It is a perspective view which shows a drum bearing part typically. It is an expanded view which shows the relationship of the generated thrust in a process cartridge. FIG. 6 is a perspective view of another embodiment showing an opening of a toner frame. (A) (b) is a longitudinal cross-sectional view which shows the coupling part of an apparatus main body and a process cartridge. It is a longitudinal cross-sectional view showing a ground contact on the photosensitive drum side. It is a front view of a ground plate. It is a perspective view which shows a ground terminal part. It is a longitudinal cross-sectional view which shows the earthing | grounding of a photoconductor drum. It is a perspective view which shows a ground terminal part. It is a longitudinal cross-sectional view which shows the earth contact of a photoconductive drum. It is a longitudinal cross-sectional view which shows the earth contact of the photoconductive drum supported by the penetration shaft. It is a longitudinal cross-sectional view which shows the earth contact of the photoconductive drum supported by the penetration shaft. It is a longitudinal cross-sectional view which shows the earth contact of the photoconductive drum supported by the penetration shaft. It is a longitudinal cross-sectional view which shows the earthing | grounding of a photoconductor drum. It is a longitudinal cross-sectional view which shows the earthing | grounding of a photoconductor drum. It is a perspective view which shows the earthing | grounding of a photoconductive drum. It is a perspective view which shows the earthing | grounding of a photoconductive drum. It is a longitudinal cross-sectional view which shows the earthing | grounding of a photoconductor drum. It is a longitudinal cross-sectional view which shows the earthing | grounding of a photoconductor drum. It is a longitudinal cross-sectional view which shows the detail of the drum flange of FIG. FIG. 57 is a right side view of FIG. 56. It is a perspective view which sees FIG. 56 from right diagonal. It is a perspective view which sees FIG. 56 from the left diagonal. FIG. 57 is a partially enlarged view of FIG. 56. FIG. 58 is a partially enlarged view of FIG. 57. It is a longitudinal cross-sectional view which shows the earthing | grounding of a photoconductor drum. It is a longitudinal cross-sectional view which shows the earthing | grounding of a photoconductor drum.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Optical system 1a ... Laser diode 1b ... Polygon mirror 1c ... Lens 1d ... Reflection mirror 1e ... Exposure opening part 2 ... Recording medium 3 ... Conveying means 3a ... Paper feed cassette 3b ... Pickup roller 3c ... Conveying roller pair 3d ... Conveying roller Pair 3e: Registration roller pair 3f: Conveying 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 ... photosensitive drum 7a ... drum shaft 7a1 ... end face 7a2 ... enlarged diameter portion 7b ... drum gear 7b1 ... side end 7d ... drum cylinder 7d1 ... inner surface 7e ... photosensitive layer 7f ... ground plate 7n ... spur gear 8 ... Charging roller 8a ... Charging roller shaft 8b ... Composite spring 8b1 ... Compression coil spring 8b2 ... Internal contact 8c ... Band Electric roller bearing 9 ... developing means 9b ... toner feeding member 9b1 ... journal 9c ... developing roller 9d ... developing blade 9d1 ... sheet metal 9d1a ... bending portion 9d2 ... urethane rubber 9d3 ... hole 9d4 ... screw hole 9d5 ... cut 9d6 ... small screw 9e ... Toner agitating member 9f ... bearing 9f1 ... key part 9g ... magnet 9g1 ... missing circular shaft 9h ... antenna rod 9h1 ... contact 9i ... spacer roller 9j ... developing roller bearing 9j1 ... hole 9j4 ... bearing 9k ... developing roller gear 9l (el) ... developing coil spring Contact 9m ... Toner stirring gear 9p ... Flange 9p1 ... Developing roller gear mounting shaft 9q ... Gear 9q1 ... Small gear 9r ... Large gear 9r1 ... Small gear 9s ... Toner feed gear 9s1 ... Shaft coupling 9s2 ... Small gear 9u ... Helical tooth Gear 9v ... Bearing box 9v1 ... Cylindrical protrusion 9v2 ... Screw hole 9 v3 ... Magnet support hole 9v4 ... Bearing fitting hole 9v5 ... Key groove 9v6 ... Recess 9v7 ... Notch 9v8 ... Notch 9v9 ... Dowel 9w ... Journal 9w1 ... Reduced diameter cylindrical part 10 ... Cleaning means 10a ... Cleaning blade 10b ... Waste toner Reservoir 11 ... toner frame 11A ... toner container 11a ... upper frame 11a1 ... flange 11b ... lower frame 11b1 ... flange 11c ... rib 11d ... toner filling port 11e ... coupling member 11e1 ... hole 11f ... toner cap 11g ... concave Part 11h: Boss 11i: Opening 11J: Toner unit 11j, 11j1 ... Flange 11k ... Concave surface 11m ... Stepped part 11n ... Groove 11n1 ... Edge 11n2 ... Bottom 11q ... Square hole 11r ... Round hole 11t ... Handle member 11v ... Projection 12 ... Development frame 12A, 12B ... Side plate 1 b ... Through hole 12c ... Female screw 12d ... Dowel 12e ... Flange 12f ... Slit 12g ... Hole 12h ... Lower jaw 12i ... Plane 12i1 ... Dowel 12i2 ... Female screw 12i3 ... Protrusion 12j ... Arc surface 12k ... Spring fixing part 12m ... Hole Part 12n: Spring guide part 12p: Opening part 12s, 12s1, 12s2 ... Seal member 12t ... Spring holding part 12u ... Plane 12v ... Projection 12v1 ... Triangular projection 12w1 ... Cylindrical dowel 12w2 ... Square dowel 12x ... Hole 12z ... Projection Strip 13 ... Cleaning frame (drum frame) 13a ... Cylindrical guide 13aR1 ... Flange 13aR2 ... Machine screw 13aR3 ... Disc member 13aR4 ... Inner diameter guide 13aR5 ... Restricted inner peripheral surface 13aR, 13aL ... Cylindrical guide 13bR, 13bL ... Non-rotating guide 13c ... Positioning pin 13d ... Small Screw 13e ... Mounting hole 13f ... Regulating contact part 13g ... Guide groove 13h ... Mounting hole 13h1 ... Circular part 13h2 ... Positioning pin 13h3 ... Rib 13h4 ... Restraining boss 13i ... Upper surface 13j ... Regulating contact part 13k ... Side end 13k1 ... Hole 13L ... Guide member 13n ... Transfer opening 13p ... Right end 13q ... Left end 13R ... Guide member 13s ... Outer wall 13t ... Partition wall 14 ... Image forming apparatus body 16 ... Guide member 16a ... Guide portion 16b ... Positioning groove 16c ... Guide 16d, positioning groove 16R, 16L ... guide member 17 ... recess 18 ... drum shutter member 18a ... shutter cover 18b, 18c ... link 18c1 ... projecting part 19 ... arm part 19a ... tip 20 ... rotating hole 20a ... inner surface 20a1 ... inclined Part 20a2 ... Spring seat part 21 ... Recessed part 21a ... Bottom 22 ... Coupling Member 22a ... compression coil spring 24 ... penetrating shaft 25 ... fixed member 26 ... penetrating shaft 27 ... penetrating shaft 29 ... flange 34 ... center hole 34a, 34b, 34c ... hole 35 ... opening / closing member 35a ... fulcrum 35b ... coupling concave shaft 36 ... Drum flange 36a ... Hole 36b ... Fitting part 36c ... Inner end face 36d ... Dowel 36e ... Arc shaped part 36f ... Concave part 36g ... Groove 37 ... Coupling convex shaft 37a ... Coupling convex part 37a1 ... Convex part end face 38 ... Bearing 38a ... Convex part 38b ... Inner end face 39 ... Gear 39a ... Concave part 39a1 ... Bottom face 39b ... Coupling concave shaft 40 ... Development holder 40a ... Support holes 40b, 40c, 40d, 40e ... Dowel 40f ... Projection 43 ... Large gear 51 ... cover film 52 ... tearing tape 52a ... end 52b ... one end 54 ... elastic sealing material 55 ... tape 56 ... Elastic seal material 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 69 ... Side plate 118 ... Ground plate 118a ... Projection 118a1 ... tip 118b ... groove 118c ... dowel hole 118d ... ground contact stop hole 118d ... opposite edge 119 ... ground contact 119a ... terminal 119b ... ground terminal 119c ... large diameter portion 119d ... small diameter portion 120 ... charging bias contact 120a ... external exposure Part 120b ... Spring seat 121 ... Development bias contact 121a ... Deriving part 121b ... Second deriving part 121c ... Third deriving part 121d ... Fourth deriving part 121e ... External contact part 121f ... Stop hole 122 ... Toner remaining amount detection Contact 123 ... Earth contact member 123a ... Sliding terminal 123b ... Body arm Terminal 123c ... flange 124 ... charging contact member 125 ... developing bias contact member 126 ... toner detecting contact point member 127 ... holder 128 ... circuit board 129 ... compression coil spring A ... laser beam printer (image forming apparatus)
B ... Process cartridge C ... Cleaning unit D ... Developing unit DG ... Developing unit drive transmission unit G ... Developing roller unit GT ... Gear train J ... Toner unit JP ... Connecting surface L, K ... Slope S ... Cartridge mounting space Z ... Horizontal line m ... Line g ... Gap

Claims (13)

A motor, a device main body side gear driven to rotate by the motor, a twisted hole having a substantially triangular cross section provided on an axis of the device main body side gear, and a main body side ground provided inside the hole; A conductive main body grounding contact disposed at the center of rotation of the hole, movable in the longitudinal direction, and biased toward the inside of the hole by an elastic force of a conductive spring A process cartridge that is detachable from the main body of the electrophotographic image forming apparatus including a main body-side ground contact that is a tip of a member,
An electrophotographic photosensitive drum;
Process means acting on the electrophotographic photosensitive drum;
A twisted protrusion having a substantially triangular cross section provided at an end in the longitudinal direction of the electrophotographic photosensitive drum, the protrusion being fitted into the hole when the process cartridge is mounted on the apparatus main body; ,
In order to ground the electrophotographic photosensitive drum between the process cartridge and the apparatus main body when the process cartridge is mounted on the apparatus main body, a cartridge-side ground contact electrically connected to the electrophotographic photosensitive drum is used. A cartridge-side ground contact provided on the protrusion so as to be electrically connected to the body-side ground contact;
Have
The electrophotographic photosensitive drum included in the process cartridge mounted on the apparatus main body is configured such that when the main body side gear receives a rotational driving force from the motor and rotates while the protrusion is fitted in the hole, the protrusion Rotation drive from the motor in a state where the main body side ground contact is urged by the elastic force of the spring toward the cartridge side ground contact in a state where the main body side ground contact is biased toward the cartridge side ground contact Force is transmitted to the electrophotographic photosensitive drum, and the electrophotographic photosensitive drum is electrically grounded to the apparatus main body through the cartridge side ground contact engaged with the main body side ground contact. Process cartridge characterized by   The process cartridge according to claim 1, wherein the cartridge-side ground contact is located on an inner side than a tip end surface of the protrusion.   The process cartridge according to claim 1, wherein the cartridge-side ground contact is located on a line coaxial with the axis of the protrusion.   The process cartridge according to claim 1, wherein the protrusion is provided at one end of a drum flange attached to one end of a drum cylinder of the electrophotographic photosensitive drum.   The drum flange includes a shaft portion rotatably supported by a bearing, a gear portion for transmitting a rotational driving force to the developing roller, and a fitting portion for fitting with a drum cylinder of the electrophotographic photosensitive drum. The protrusion is provided at a side end of the shaft portion, and the cartridge-side ground contact is located on the same axis as the axis of the drum flange, and the inside of the drum flange is axially The process cartridge according to claim 4, wherein the process cartridge is a front end surface of a conductive member passing along the surface.   A ground plate is attached to a portion of the drum flange located on the inner side of the electrophotographic photosensitive drum, and the ground plate has a hole through which the conductive member passes, and a first contact with the conductive member. The process cartridge according to claim 4, further comprising a contact portion and a second contact portion that contacts an inner surface of a cylinder of the electrophotographic photosensitive drum. In an electrophotographic image forming apparatus for forming an image on a recording medium,
(A) a motor;
(B) an apparatus main body side gear that receives a driving force from the motor;
(C) a twisted hole having a substantially triangular cross section provided on a coaxial line with the gear;
(D) A body-side ground contact provided inside the hole, disposed at the center of rotation of the hole, movable in the longitudinal direction, and by the elastic force of a conductive spring, A body-side ground contact that is a tip of a conductive body ground contact member that is biased inward;
(E) an electrophotographic photosensitive drum;
Process means acting on the electrophotographic photosensitive drum;
A twisted protrusion having a substantially triangular cross section provided at an end in the longitudinal direction of the electrophotographic photosensitive drum, wherein the hole is formed when the process cartridge is mounted on the main body of the electrophotographic image forming apparatus. A protrusion that fits into the
In order to ground the electrophotographic photosensitive drum between the process cartridge and the apparatus main body when the process cartridge is mounted on the apparatus main body, a cartridge-side ground contact electrically connected to the electrophotographic photosensitive drum is used. A cartridge-side ground contact provided on the protrusion so as to be electrically connected to the body-side ground contact;
A process cartridge that is detachably mounted on the apparatus main body, and
The electrophotographic photosensitive drum included in the process cartridge mounted on the apparatus main body is configured such that when the main body side gear receives a rotational driving force from the motor and rotates while the protrusion is fitted in the hole, the protrusion Rotation drive from the motor in a state where the main body side ground contact is urged by the elastic force of the spring toward the cartridge side ground contact in a state where the main body side ground contact is biased toward the cartridge side ground contact Force is transmitted to the electrophotographic photosensitive drum, and the electrophotographic photosensitive drum is electrically grounded to the apparatus main body through the cartridge side ground contact engaged with the main body side ground contact. An electrophotographic image forming apparatus. The electrophotographic image forming apparatus according to claim 7 , wherein the cartridge-side ground contact is located on an inner side than a tip end surface of the protrusion. 9. The electrophotographic image forming apparatus according to claim 7 , wherein the cartridge-side ground contact is located on a line coaxial with an axis of the protrusion. The electrophotographic image forming apparatus according to claim 7 , wherein the protrusion is provided at one end of a drum flange attached to one end of a drum cylinder of the electrophotographic photosensitive drum. The drum flange includes a shaft portion rotatably supported by a bearing, a gear portion for transmitting a rotational driving force to the developing roller, and a fitting portion for fitting with a drum cylinder of the electrophotographic photosensitive drum. The protrusion is provided at a side end of the shaft portion, and the cartridge-side ground contact is located on the same axis as the axis of the drum flange, and the inside of the drum flange is axially The electrophotographic image forming apparatus according to claim 10 , wherein the electrophotographic image forming apparatus is a front end surface of a conductive member passing along the surface. A ground plate is attached to a portion of the drum flange located on the inner side of the electrophotographic photosensitive drum, and the ground plate has a hole through which the conductive member passes, and a first contact with the conductive member. The electrophotographic image forming apparatus according to claim 10 , further comprising a contact portion and a second contact portion that contacts an inner surface of a cylinder of the electrophotographic photosensitive drum. The electrophotographic image forming apparatus according to claim 7, wherein the protrusion is a twisted substantially equilateral triangular prism, and the hole has a substantially equilateral triangular cross section.