Patent ID: 6999696

Claim:
A coupling part for an photosensitive drum engageable with a driving member of an electrophotographic image forming apparatus, the driving member having a twisted hole and a main assembly grounding contact provided in the hole, the coupling part comprising: a projection provided at a longitudinal end of the photosensitive drum and having a plurality of engaging portions engageable with an inner surface of the hole, the arrangement being such that when the driving member rotates with the hole and said projection engaged with each other, a rotational driving force is transmitted from the driving member to the photosensitive drum through engagement between the hole and said projection; and a cartridge grounding contact electrically connectable with the photosensitive drum to electrically ground the photosensitive drum when the hole and said projection are engaged with each other, said cartridge grounding contact being disposed substantially at a center of said projection and being electrically connectable with the main assembly grounding contact.