Patent ID: 7092658

Claim:
An image forming apparatus for forming an image on a recording material comprising: an image bearing member detachably mountable to the image forming apparatus; a driving source; coupling means for transmitting a driving force from said driving source; to said image bearing member, said coupling means comprising a rotatable first coupling portion including a coupling projection having a polygonal cross-section, and a rotatable second coupling portion, including a twisted hole having a cross-section larger than the cross-section of said coupling protection, for coupling engagement with said first coupling portion, wherein at least one of said first coupling portion and said second coupling portion is mounted to said image bearing member; a shaft provided on said first coupling portion and extending from an end surface of said first coupling portion in a direction in which said first coupling portion and said second coupling portion are coupleable with each other; and an engageable hole, provided in said second coupling portion for engagement with said shaft, for determining a positional relation between said first coupling portion and said second coupling portion.