Electrophotographic image forming apparatus, process cartridge, developing device and measuring part

摘要

A process cartridge detachably mountable to an electrophotographic image forming apparatus, said process cartridge includes (a) an electrophotographic photosensitive member; (b) process means actable on the electrophotographic photosensitive member; (c) a measuring electrode member having input side and output side electrodes having at least one juxtaposed portions, the measuring electrode member being disposed at such a position that it is contacted to a developer; (d) a reference electrode member having input side and output side electrodes having at least one juxtaposed portions, the reference electrode member being disposed at such a position that it is out of contact to the developer; (e) an output contact for the measuring electrode member, connected electrically to the output side electrode of the measuring electrode member; (f) an output contact for the reference electrode member, connected electrically to the output side electrode of the reference electrode member; and (g) a common input contact connected electrically to the input side electrodes of the measuring electrode member and the reference electrode member.