The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 08, 1981
Filed:
Sep. 07, 1977
Noboru Kutsuwada, Tokyo, JP;
Minoru Saito, Hachioji, JP;
Ryoichi Namiki, Hino, JP;
Katsuo Kusunoki, Machida, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A photosensitive member is exposed to light prior to primary charging so that the surface potential applied by primary charging may always be maintained at a constant level to which the photosensitive member is always charged when it is repetitively used for some time, which may be predetermined by test. Until the surface potential reaches this level, the intensity of light for pre-exposure is gradually decreased and after the surface potential has reached this level, no pre-exposure is applied. But when the surface potential rises after a predeterminable period during which the photosensitive member is not used, the pre-exposure is applied again. All the copies may have the same density.