Abstract: A developer amount detecting method for detecting a developer amount for developing an electrostatic latent image formed on an electrophotographic photosensitive member includes a first process for successively detecting the amount of the developer contained in a containing portion by counting the number of individual image signals for forming dots of an image by a main body of an electrophotographic image forming apparatus; and a second process for successively detecting the developer amount by the apparatus main body by transmitting an electric signal according to the amount of the developer contained in the containing portion to the apparatus main body.

Abstract: A developing device includes a developer container which is mountable to an electrophotographic image forming apparatus main body, contains a developer for developing an electrostatic latent image formed on an electrophotographic photosensitive member, and includes a developer bearing member for carrying the developer to the electrophotographic photosensitive member, and a plurality of developer remaining amount detectors for successively detecting the remaining amount of developer within the developer container, wherein regions detected by the plurality of developer remaining amount detectors are overlapped with each other, and in the overlapped regions, a detected value by a previous developer remaining amount detector is changed over to a detected value by a succeeding developer remaining amount detector, and the apparatus main body detects the detected value to detect the remaining amount of developer.

Abstract: An unit detachably mountable to a main assembly of an electrophotographic image forming apparatus for forming an image on a recording material, comprising: (a) a unit including; a unit frame; and (b) a memory member provided in the process cartridge, the memory member having; a base; a storing element, provided on the base, for storing information; a memory antenna, provided in the base, for sending the information stored in the storing element to a main assembly antenna provided in a main assembly of the apparatus, when the memory member is mounted to the main assembly of the apparatus; a sending member, provided in the base, for sending the information stored in the storing element to the memory antenna; and an outer casing member covering the base provided with the storing element, the sending member and the memory antenna, wherein when the unit is mounted to the main assembly of apparatus, the unit frame is contacted to a main assembly antenna cover provided in the main assembly of the apparatus.

Abstract: A memory member usable with an electrophotographic image forming apparatus, includes a base; a storing element, provided in the base, for storing information; a memory antenna, provided in the base, for sending the information stored in the storing element to a main assembly antenna provided in a main assembly of the apparatus, when the memory member is mounted to the main assembly of the electrophotographic image forming apparatus; a sending member, provided in the base, for sending the information stored in the storing element to the memory antenna; and an outer casing member covering the base provided with the storing element, the sending member and the memory antenna.

Abstract: An unit detachably mountable to a main assembly of an electrophotographic image forming apparatus for forming an image on a recording material, comprising: (a) a unit frame; and (b) a memory member supported by said unit frame, said memory member including: a base; a storing element, provided on said base, for storing information; a memory antenna, provided in said base, for sending the information stored in said storing element to a main assembly antenna provided in a main assembly of the apparatus, when said memory member is mounted to the main assembly of the apparatus; a sending member, provided in said base, for sending the information stored in said storing element to said memory antenna; and an outer casing member covering said substrate provided with said storing element, said sending member and said memory antenna, wherein said memory member is disposed substantially at a central portion of said unit frame with respect to a direction crossing with a mounting direction in which said unit is mounted to

Abstract: An electrophotographic image formation system for forming an image on a recording material, the improvement residing in that when a process cartridge is mounted, to form an image on a recording material, to a main assembly of an electrophotographic image forming apparatus including a main assembly antenna covered with a main assembly antenna outer casing member, the process cartridge including an electrophotographic photosensitive member, process means actable on the electrophotographic photosensitive member, a storing element storing information, a memory antenna for communication with the main assembly antenna, and a memory antenna outer casing member for covering the storing element and the memory antenna, positioning is effected for a gap between the memory antenna and the main assembly antenna by contact between an outer surface of outer casing member and an outer surface of an outer casing member of the main assembly antenna.

Abstract: A developing device for developing an electrostatic latent image formed on an electrophotographic photosensitive member, the developing device being usable with a main assembly of an electrophotograhic image forming apparatus, the developing device includes a developing member for supplying a developer to the electrophotographic photosensitive member for developing the electrostatic latent image formed on the electrophotographic photosensitive member; a first electrode provided opposed to developing member; a second electrode disposed such that at least a lower end thereof takes a position lower than the first electrode when the developing device is mounted to the main assembly of the electrophotographic image forming apparatus; wherein an electric signal is generated in accordance with an electrostatic capacity between the first electrode and second electrode when the first electrode or second electrode is supplied with a voltage from the main assembly of the electrophotographic image forming apparatus, and

Abstract: A developing device for developing an electrostatic latent image formed on an electrophotographic photosensitive member, said developing device being mountable to a main assembly of an electrophotographic image forming apparatus, said developing device includes a developer carrying member for feeding a developer to said electrophotographic photosensitive member to develop the electrostatic latent image formed on the electrophotographic photosensitive member; a first electroconductive portion; a second electroconductive portion for cooperating with said first electroconductive portion to provide an electrostatic capacity; a first electrical contact for receiving a voltage to be applied to said first electroconductive portion from the main assembly of the electrophotographic image forming apparatus; a second electrical contact for transmitting, to the main assembly of the electrophotographic image forming apparatus, an electric signal corresponding to an electrostatic capacity between said first electroconducti

Abstract: In a developer amount successively indicating method used in an electrophotographic image forming apparatus capable of detachably mounting a plurality of types of cartridges differing in the fill amount of a developer, an indicating portion selected in conformity with the type of one of the plurality of types of cartridges which is mounted in the main body of the electrophotographic image forming apparatus is indicated, and the detected amount of developer in the cartridge mounted in the main body of the electrophotographic image forming apparatus is successively indicated by the use of the indicating portion.

Abstract: A developing device to be mounted on an electrophotographic image forming apparatus main body and used for developing an electrostatic latent image formed on an electrophotographic photosensitive member, including a developing container, an electrode attached to the inside of the developing container, a conductive member for securing electric conduction from the inside to the outside of the developing container, wherein the conductive member and the electrode are electrically connected by the conductive member being press-fit in a fitting portion provided in the electrode, and an elastic sealing member press-fit in a gap between the conductive member and the developing container.

Abstract: An electrophotographic process cartridge and an image forming apparatus using such a process cartridge are provided. The process cartridge includes a casing member containing a photosensitive drum; a driven gear co-axial with the drum; a charging member, a developing member, and a cleaning member operable on the drum; and a protuberance adjacent one end of the drum and protruding outwardly of the casing member at one side thereof. An earth contact is provided by the protuberance at the one side of the casing member, and a charging bias contact and a developing bias contact are provided at an opposite side of the casing member and are disposed adjacent to and respectively forwardly and rearwardly of an axis of the drum relative to an insertion direction of the process cartridge into the image forming apparatus.

Abstract: An electrophotographic image forming apparatus for forming an image on a recording medium comprises an electrophotographic photosensitive member, an electrostatic latent image forming device for forming an electrostatic latent image on the electrophotographic photosensitive member, a developing device for developing the electrostatic latent image formed on the electrophotographic photosensitive member, a developer remaining amount detecting device for successively detecting the remaining amount of developer to be used for the development of the electrostatic latent image by the developing device, and a developer remaining amount indicating device for indicating the remaining amount of developer detected by the developer remaining amount detecting device. The developer remaining amount indicating device indicates the remaining amount of developer as a gauge and indicates it with graduations shown on the gauge being changed over in conformity with the remaining amount of developer.

Abstract: A developing apparatus for developing a latent image formed on an electrophotographic photosensitive member, includes (a) a developer carrying member for feeding a magnetic developer to develop a latent image formed on the electrophotographic photosensitive member with the magnetic developer, wherein a magnet is disposed in the developer carrying member; (b) a magnetic seal member provided at each of one and the other longitudinal ends of the developer carrying member with a clearance from a peripheral surface of the developer carrying member to prevent leakage of the developer in a longitudinal direction of the developer carrying member; (c) a developer regulating member provided contacted to the peripheral surface of the developer carrying member to prevent reentering of the developer having passed through the gap between the developer carrying member and the magnetic seal member.

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 conne

Abstract: A developing apparatus includes a developing roller; a magnetic seal provided at a longitudinal end of the developing roller; a positioning surface between a developing frame supporting the developing roller and a bottom end of the magnetic seal, the positioning surface being in contact with the developing frame and the magnetic seal; an end seal provided between the developing frame and the bottom end of the magnetic seal.

Abstract: A developing device includes a developer container containing magnetic particles; a developer holding unit formed at an opening portion of the developer container, the developer holding unit rotating while holding a developer; a magnetic field generating unit placed in the developer holding unit; a magnet placed along a circumferential direction of the developer holding unit to form a magnetic seal between the magnet and the developer holding unit; and a magnetic unit placed to be adjacent to the magnet. The developing device attains a reduction in driving torque and a high magnetic sealing performance.

Abstract: A process cartridge detachably mountable to an image forming apparatus includes an image bearing member; process device actable on the image bearing member; a first frame containing the image bearing member and the process device; and a second frame engageable with and disengageable from the first frame and containing a developer container.

Abstract: A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus includes an electrophotographic photosensitive member; and developing member for developing a latent image formed on the photosensitive member; The developing member is disposed at a position deviated from a developing position corresponding to a displacement of the developing member resulting from the driving force received from the main assembly of the apparatus when the process cartridge is in the main assembly.

Abstract: A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus includes an electrophotographic photosensitive member; a cartridge coupling member, provided coaxially with the photosensitive member, for engaging with a main assembly coupling member to receive driving force for rotating the photosensitive member when the process cartridge is mounted to the main assembly; a developing roller for supplying toner to the photosensitive member to develop a latent image formed on the photosensitive member; a driving force transmission member, disposed at one longitudinal end of the photosensitive member to transmit the driving force from the photosensitive member to the developing roller; a driving force receiving member, engaged with the driving force transmission member and disposed at one longitudinal end of the developing roller, for receiving the driving force for rotating the developing roller; and a magnetic seal member, disposed with a gap from the developing rol

Abstract: The present invention provides a process cartridge mountable to an image forming apparatus, comprising an image bearing member, at least one process means acting on the image bearing member, and a detection member for detecting the presence/absence of developer supplied to the image bearing member on the basis of electrostatic capacity.