Abstract: An image forming apparatus includes an image bearing member, wherein a toner image is formed on the image bearing member and is transferred onto a recording material, thus forming an image on the recording material; a shaft for rotating the image bearing member, wherein the shaft is provided with a first projection and a second projection, and the image bearing member is provided with a first engaging portion and a second engaging portion which are engageable with the first projection and the second projection, respectively, and wherein the first engaging portion is abuttable to the first projection at downstream and upstream sides of the first projection with respect to a rotational direction of the shaft, and the second engaging portion is abuttable to the second projection at a downstream side of the second projection, and wherein a gap is provided between the second engaging portion and the second projection at an upstream side of the second projection.

Abstract: An electrophotographic photosensitive drum is for a process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus. The main assembly includes a motor, and a gear having a non-circular twisted hole. The drum includes a cylinder having a non-circular twisted projection engageable with the hole to receive a driving force from the main assembly when the cartridge is mounted to the main assembly. A recess is formed in of the projection and has a bottom portion and a side surface portion. When the projection receives a pulling force toward the hole by rotation of the gear with the projection and the hole being engaged with each other, the bottom portion contacts a spherical surface portion provided at a central portion of the hole, and the side surface portion contacts the spherical surface portion.

Abstract: An electrical contact member is usable with a process cartridge, and is for establishing an electrical connection between the process cartridge and a main assembly of an electrophotographic image forming apparatus, when the process cartridge is mounted to the main assembly of the apparatus. The process cartridge includes an electrophotographic photosensitive drum and a process device actable on the photosensitive drum.

Abstract: A drive transmission apparatus includes a first coupling portion having a polygonal shape; a second coupling portion having a hole portion which has a cross-sectional configuration larger than the first coupling portion, the hole portion being engageable with the first coupling portion; and a center shaft provided on the first coupling or the second coupling, the center shaft penetrating the other one of the first and second coupling.

Abstract: The image forming apparatus includes a conveying unit having a conveying member and a first transmitting portion and a driving frame for supporting the second transmitting portion, wherein the conveying unit is mountable to or removable from a body of the apparatus and when mounted, the first transmitting portion engages with the second transmitting portion and the driving frame has a positioning portion for positioning the conveying unit. By the above virtue of the image forming apparatus, the positioning accuracy of the conveying unit is improved and brings a high-quality color image.

Abstract: A drive transmission apparatus includes a first coupling portion having a polygonal shape; a second coupling portion having a hole portion which has a cross-sectional configuration larger than the first coupling portion, the hole portion being engageable with the first coupling portion; and a center shaft provided on the first coupling or the second coupling, the center shaft penetrating the other one of the first and second coupling.

Abstract: A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus includes an electrophotographic photosensitive drum; a process device actable on the electrophotographic photosensitive drum; and a load producing member for imparting a load on a peripheral surface of a cylindrical member rotatable with the photosensitive drum to increase a rotational torque required for rotation of the photosensitive drum.

Abstract: The image forming apparatus includes a conveying unit having a conveying member and a first transmitting portion and a driving frame for supporting the second transmitting portion, wherein the conveying unit is mountable to or removable from a body of the apparatus and when mounted, the first transmitting portion engages with the second transmitting portion and the driving frame has a positioning portion for positioning the conveying unit. By the above virtue of the image forming apparatus, the positioning accuracy of the conveying unit is improved and brings a high-quality color image.

Abstract: An electrical contact member, usable with a process cartridge, for establishing electrical connection between the process cartridge and a main assembly of an electrophotographic image forming apparatus, when the process cartridge is mounted to the main assembly of the apparatus, the process cartridge including an electrophotographic photosensitive drum and process means actable on the photosensitive drum, the electrical contact member including a base member; a mounting portion for mounting the base member to a frame of the process cartridge; a positioning portion for positioning the base member in the frame when the base member is mounted to the frame of the process cartridge by the mounting portion; an electrical contact portion, projected from the base member, for establishing electrical connection with a main assembly side electrical contact member, which is provided in the main assembly of the apparatus, by pressing in a direction against the main assembly side electrical contact member when the process

Abstract: A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, the process cartridge includes an electrophotographic photosensitive drum; process means actable on the electrophotographic photosensitive drum; a load producing member for imparting a load on a peripheral surface of a cylindrical member rotatable with the photosensitive drum to increase a rotational torque required for rotation of the photosensitive drum.

Abstract: A drive transmission apparatus includes a first coupling portion having a polygonal shape; a second coupling portion having a hole portion which has a cross-sectional configuration larger than the first coupling portion, the hole portion being engageable with the first coupling portion; and a center shaft provided on the first coupling or the second coupling, the center shaft penetrating the other one of the first and second coupling.