US Patent 8095036 Process cartridge

A member for performing separation holding of a developing roller of a process cartridge is provided at a position opposite from a photosensitive drum with respect to a swing center. A detachably mountable protective cover is mounted to the process cartridge and a projection of the protective cover is inserted between the photosensitive drum and a developing device frame which supports the developing roller. The projection of the protective cover is inserted in a non-contact state with the photosensitive drum and the developing device frame.