Patent Number: 6,253,036

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

Abstract: A process cartridge detachably mountable to an electrophotographic image forming apparatus, the process cartridge including (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 portion, 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.

Inventors: Karakama; Toshiyuki (Shizuoka-ken, JP), Sakata; Shirou (Mishima, JP), Matsumoto; Hideki (Mishima, JP), Yokoi; Akiyoshi (Shizuoka-ken, JP)

Assignee: Canon Kabushiki Kaisha

International Classification: G03G 21/18 (20060101); G03G 15/08 (20060101); G03G 015/08 ()

Expiration Date: 06/26/2018