Patent ID: 6823153
Filing Date: 2004-11-23
Classification: G03G

Abstract:
A developing device for developing a latent image formed on an electrophotographic photosensitive member used in an electrophotographic image forming apparatus, said developing device comprising:a developing member configured and positioned to develop a latent image formed on the electrophotographic photosensitive member; an exposure optical path configured and positioned to guide an exposure light emitted from exposure means mounted in a body of the electrophotographic image forming apparatus to the electrophotographic photosensitive member; a developer containing portion configured and positioned to contain a developer which is used by said developing member for developing the latent image; a vent port configured and positioned to allow air in the inside of said developer containing portion to pass therethrough; a cover member extending along a longitudinal direction of said developing member, said cover member being disposed between said exposure optical path and said developing member in the rotational direction of the electrophotographic photosensitive member, a first sheet member configured and positioned to prevent scattering of the developer into said exposure optical path, said first sheet member being disposed on said cover member and being in contact with the electrophotographic photosensitive member in the longitudinal direction of the electrophotographic photosensitive member; a first sealing member configured and positioned to prevent leaking of the developer in the inside of said developer containing portion from said developer containing portion, said first sealing member being in contact with one end portion of the electrophotographic photosensitive member, one end portion of said developing member and one end portion of said cover member in the longitudinal direction of the electrophotographic photosensitive member; and a second sealing member configured and positioned to prevent leaking of the developer in the inside of said developer containing portion from said developer containing portion, said second sealing member being in contact with another end portion of the electrophotographic photosensitive member, another end portion of said developing member and another end portion of said cover member in the longitudinal direction of the electrophotographic photosensitive member.