Abstract: The image forming apparatus has a developer container containing a developer therein, a developer toner density detecting portion for detecting the permeability of the developer in the developer container to thereby detect toner density, and an engine controller for detecting whether the image forming apparatus has gone wrong, on the basis of the toner density detected by the developer toner density detecting portion. Thereby, it becomes possible to detect the failure of a developing apparatus reliably and early by an inexpensive construction.

Abstract: The present invention relates to a developing apparatus for developing an electrostatic latent image formed on an electrophotographic photosensitive drum using a developing agent, including a developing agent carrier for supplying the developing agent to the photosensitive drum to develop the electrostatic latent image formed on the photosensitive drum, a layer thickness limiting member for limiting the layer thickness of the developing agent carried on a surface of the developing agent carrier, the layer thickness limiting member being disposed with a gap to the developing agent carrier, a sealing member for restricting the developing agent from leaking out of an end in a longitudinal direction of the developing agent carriers and an elastic member arranged in contact with the developing agent carrier to prevent the gap between the developing agent carrier and the layer thickness limiting member from changing upon bending of the developing agent carrier.

Abstract: A process cartridge and a unit include a cover member, a memory element provided on the cover member, and a unit abutting portion. The process cartridge and the unit can be detachably mounted to the main body of an electrophotographic image forming apparatus. The main body of the electrophotographic image forming apparatus includes a main body base member and a communication device. The process cartridge and the unit are positioned to a predetermined location by the unit abutting portion abutting against the main body base member, when the process cartridge and the unit are mounted to the main body of the electrophotographic image forming apparatus. In this state, the storage element is disposed at a position facing the communication device and can communicate with it in a noncontacting manner.

Abstract: A process cartridge remanufacturing method including the steps of: (a) separating photosensitive drum and developing units; (b) dismounting a first side cover member; (c) a dismounting a first gear group from a first bearing member; (d) dismounting a supporting member from the first bearing member; (e) dismounting a second gear group from the first bearing member; (f) dismounting the first bearing member; (g) dismounting a developing roller; (h) dismounting a developing blade; (i) filling a developer into a developer accommodating portion; (j) mounting the developing blade; (k) mounting the developing roller; (l) mounting the second gear group, (m) mounting the supporting member; (n) mounting the first gear group; (o) mounting the first side cover member; and (p) rotatably connecting the photosensitive drum and developing units.

Abstract: A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus includes an electrophotographic photosensitive drum, a process device actable on the drum, a drum frame, first and second drum frame openings at a different longitudinal ends of the drum frame, first and second end regulating portions at different longitudinal ends of the drum frame, a drum shaft with a through hole, a drum end flange with an end flange opening for receiving the drum shaft, first and second openings provided opposite from each other at a periphery of the end flange opening, and a connecting member penetrating the first opening and the through hole and engaged with the second opening to connect the photosensitive drum with the drum shaft. The regulating portions regulate the position of the drum in its longitudinal direction and the connecting member connects the drum shaft with the drum.

Abstract: An electrical contact member is usable with a process cartridge, and is for establishing an electrical connection between the process cartridge and a main assembly of an electrophotographic image forming apparatus, when the process cartridge is mounted to the main assembly of the apparatus. The process cartridge includes an electrophotographic photosensitive drum and a process device actable on the photosensitive drum.

Abstract: A drive transmission apparatus includes a first coupling portion having a polygonal shape; a second coupling portion having a hole portion which has a cross-sectional configuration larger than the first coupling portion, the hole portion being engageable with the first coupling portion; and a center shaft provided on the first coupling or the second coupling, the center shaft penetrating the other one of the first and second coupling.

Abstract: A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, includes a drum, a developing member, a cartridge frame including a developer accommodating portion, a first light guide adjacent one end of the cartridge frame and a leading end with respect to a cartridge mounting direction and including a light entrance portion opposed to an emitting portion to receive detecting light when the process cartridge is mounted to the main assembly and guiding the detecting light to cross with a developer accommodating space in the developer accommodating container, a second light guide adjacent the one end and the leading end, and including a light exit portion and directing, the detecting light having passed through the developer accommodating space to the light receiving portion, and a memory member communicatable with the main assembly and adjacent the one end o and the leading and including a cartridge electrical contact.

Abstract: A process cartridge which is capable of being carried on a movable guide provided in the main assembly of an electrophotographic image forming apparatus and which is movable from a receiving position toward a mount position in interrelation with movement of the movable guide, includes an electrophotographic photosensitive drum; process means actable on the drum; a cartridge frame supporting the drum and the process means; a first portion to be carried, provided at one longitudinal end of the drum, for being supported by the movable guide; a second portion to be carried, provided at the other longitudinal end of the drum, for being supported by the movable guide; a first positioning portion to be positioned relative to a main assembly, the first positioning portion extending outwardly from the cartridge frame adjacent the one longitudinal end of the drum; a second positioning portion to be positioned relative to the main assembly, the second positioning portion extending outwardly from the cartridge frame adja

Abstract: A process cartridge which is capable of being carried on a movable guide, which is movable relative to a main assembly of an electrophotographic image forming apparatus and which is provided in the main assembly, the movable guide being movable from a receiving position toward a mount position in interrelation with movement of the movable guide, includes an electrophotographic photosensitive drum; process means actable on the drum; a cartridge frame; a first positioning portion to be positioned relative to a main assembly, when the cartridge is mounted to the main assembly, the first positioning portion extending outwardly from the framee adjacent the one longitudinal end of the drum; a second positioning portion to be positioned relative to the main assembly, when the cartridge is mounted to the main assembly, the second positioning portion extending outwardly from the framee adjacent the other longitudinal end of the drum; a first portion to be carried, provided at one longitudinal end of the drum, for bein

Abstract: A plurality of process cartridges, each including an electrophotographic photosensitive drum, and a process device actable on the photosensitive drum, are detachably mountable to an electrophotographic image forming apparatus for forming an image of a recording medium. The image forming apparatus includes an opening and closing member; an intermediate transfer member or a recording medium bearing member provided in the opening and closing member such that the intermediate transfer member can face the process cartridges under a condition in which the opening and closing member is closed, and the intermediate transfer member can be separated from the process cartridges under a condition in which the opening and closing member is open; and a moving guide for holding the process cartridges.

Abstract: The developer agitating member has a shaft portion, a spiral rib and an inclined rib protruding from the outer peripheral surface of the shaft portion and provided in the spiral rib in the axial direction of the shaft portion. As a result, in a developing apparatus, a process cartridge and an image forming apparatus, the developer agitating member can efficiently agitate and convey a developer.

Abstract: A drive transmission apparatus includes a first coupling portion having a polygonal shape; a second coupling portion having a hole portion which has a cross-sectional configuration larger than the first coupling portion, the hole portion being engageable with the first coupling portion; and a center shaft provided on the first coupling or the second coupling, the center shaft penetrating the other one of the first and second coupling.

Abstract: A developing device includes a developing member for developing the latent image, an exposure optical path, a developer containing portion, a vent port for allowing air in the inside of the developer containing portion to pass therethrough, a first sheet member for preventing scattering of the developer into the exposure optical path, disposed between the exposure optical path and the developing member and contacted with an electrophotographic photosensitive member, a first sealing member for preventing leaking of the developer from the developer containing portion, contacted with one end portion of the electrophotographic photosensitive member in its longitudinal direction, and a second sealing member for preventing leaking of the developer from the developer containing portion, contacted with another end portion of the electrophotographic photosensitive member in its longitudinal direction.

Abstract: A process cartridge including a flexible member capable of taking a protection position in which the flexible member protects an electrophotographic photosensitive member, and a retraction position in which the flexible member retracts from the protection position, a support member having a support portion on which the flexible member is supported, provided pivotably on a cartridge frame and adapted to move the flexible member from the protection position to the retraction position, and a regulating member provided on the flexible member so as to regulate the positions of creases which occur on the flexible member in accordance with a pivotal movement of the support member, and which extend in parallel with the longitudinal direction of the member of an electrophotographic photosensitive member, the flexible member being folded on the creases and moved to the retraction position.

Abstract: A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus includes an electrophotographic photosensitive drum; a process device actable on the electrophotographic photosensitive drum; and a load producing member for imparting a load on a peripheral surface of a cylindrical member rotatable with the photosensitive drum to increase a rotational torque required for rotation of the photosensitive drum.

Abstract: An object of the present invention is to provide a developing apparatus capable of reducing unevenness of density of an image in a longitudinal direction of a photosensitive member. For this purpose, in the present invention, a developing apparatus includes a developer bearing member, and a developer carrying screw placed adjacently to the developer bearing member in parallel with the developer bearing member, and an inclination angle of “a carrying surface facing in a developer carrying direction of a spiral blade of the developer carrying screw” to a shaft of the developer carrying screw is equal to or less than 60 degrees.

Abstract: The developer agitating member has a shaft portion, a spiral rib and an inclined rib protruding from the outer peripheral surface of the shaft portion and provided in the spiral rib in the axial direction of the shaft portion. Thereby, in a developing apparatus, a process cartridge and an image forming apparatus, the developer agitating member can efficiently agitate and convey a developer.

Abstract: The present invention relates to a developing device which includes a developing member for developing the latent image, an exposure optical path, a developer containing portion, a vent port for allowing air in the inside of the developer containing portion to pass therethrough, a first sheet member for preventing scattering of the developer into the exposure optical path, disposed between the exposure optical path and the developing member and contacted with an electrophotographic photosensitive member, a first sealing member for preventing leaking of the developer from the developer containing portion, contacted with one end portion of the electrophotographic photosensitive member in the longitudinal direction of its, and a second sealing member for preventing leaking of the developer from the developer containing portion, contacted with another end portion of the electrophotographic photosensitive member in the longitudinal direction of its.

Abstract: The image forming apparatus has a developer container containing a developer therein, a developer toner density detecting portion for detecting the permeability of the developer in the developer container to thereby detect toner density, and an engine controller for detecting whether the image forming apparatus has gone wrong, on the basis of the toner density detected by the developer toner density detecting portion. Thereby, it becomes possible to detect the failure of a developing apparatus reliably and early by an inexpensive construction.