Electrophotographic image forming apparatus and process cartridge detachably mountable thereto comprising a positioning portion for engagement with a positioning member of a main assembly of the image forming apparatus

An electrophotographic image forming apparatus for forming an image on a recording material, wherein a process cartridge is detachably mountable to a main assembly of said image forming apparatus, comprising:

• a) a positioning member for positioning said process cartridge;
• b) a driving force transmission member rotatably supported on said positioning member and having a first projection concentric with an electrophotographic photosensitive member contained in said process cartridge and a plurality of second projections arranged radially from said first projection;
• c) mounting means for detachably mounting said process cartridge, wherein said process cartridge includes:
• the photosensitive member;
• process means actable on said photosensitive member;
• a frame for supporting at least said photosensitive member;
• a positioning portion, provided on said frame coaxially with said photosensitive member, for engagement with said positioning member;
• a driving force receiving member, disposed at said positioning portion, for receiving a driving force from the driving force transmission member;
• wherein said receiving member includes a first hole portion for engagement with said first projection of the transmission member to position said receiving member, said first hole portion being concentric with said photosensitive member when said process cartridge is mounted to the main assembly of said apparatus, and further includes a plurality of second hole portions for driving force transmission, said plurality of second hole portions arranged radially from said first hole portion to be engageable with said second projections of the transmission member for driving force transmission, when said process cartridge is mounted to the main assembly of said apparatus.