Patent ID: 7231161

Claim:
A process cartridge which is detachably mountable to a main assembly of an electrophotographic image forming apparatus for forming an image on a recording material, which apparatus includes a motor, a main assembly rotatable driving member configured to transmit a driving force from the motor, a twisted projection provided at the central portion of and integrally rotatable with a driving rotatable member and having a non-circular cross-section with a plurality of corner portions, and a main assembly grounding contact surrounded by the plurality of corner portions, wherein the main assembly grounding contact is an end portion, disposed at the rotational center of a hole of an electrophotographic main assembly grounding contact member which is urged toward the hole by a resilient force of an electroconductive spring member, said process cartridge comprising: an electrophotographic photosensitive drum; process means actable on said electrophotographic photosensitive drum; a twisted hole formed in a longitudinal end of said electrophotographic photosensitive drum and having a non-circular cross-section with a plurality of corner portions, said twisted hole being engageable with the twisted projection; and a cartridge grounding contact electrically connected with said electrophotographic photosensitive drum for electrically grounding said electrophotographic photosensitive drum when said process cartridge is mounted to the main assembly of said apparatus, said cartridge grounding contact being provided in said twisted hole so as to be electrically connectable with the main assembly grounding contact, wherein the arrangement is such that when the main assembly rotatable driving member rotates with inner surfaces of said twisted hole and engaging portions of the projection engaged with each other, said twisted hole is urged toward the projection with the main assembly grounding contact urged toward the cartridge grounding contact by the spring member, and a rotational driving force is transmitted from the main assembly rotatable driving member to said photosensitive drum through engagement between said twisted hole and the projection.