Electrophotographic image forming apparatus, process cartridge, developing device, developer supply container and measuring part therefor

摘要

An electrophotographic image forming apparatus for forming an image on a recording material includes a first electrostatic capacity generating portion disposed at such a position that first electrostatic capacity generating portion is contacted to the developer accommodated in said developer accommodating portion when a predetermined amount of the developer is accommodated in said developer accommodating portion, said first electrostatic capacity generating portion generating an electrostatic capacity corresponding to an amount the developer when said first electrostatic capacity generating portion is supplied with a voltage, and a second electrostatic capacity generating portion disposed at such a position that second electrostatic capacity generating portion is not contacted to the developer accommodated in said developer accommodating portion, said second electrostatic capacity generating portion generating a reference electrostatic capacity when said second electrostatic capacity generating portion is supplied with a voltage; developer amount detecting means for detecting an amount of the developer accommodated in said developer accommodating portion on the basis of the electrostatic capacity generated by said first electrostatic capacity generating portion and the reference electrostatic capacity generated by said second electrostatic capacity generating portion; electrostatic latent image forming means for forming an electrostatic latent image on said electrophotographic photosensitive member.