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:
Apr. 30, 1991
Filed:
Jan. 11, 1989
Fujitsu Limited, Kawasaki, JP;
Abstract
A brush type charging unit having a constant-current regulated power supply for supplying a constant current to a moving photosensitive medium through a conductive brush fiber contacting the moving photosensitive medium for charging the photosensitive medium uniformly such that the charged potential varies within a range smaller than 10 V when an atmospheric condition changes from 5.degree. C.-20% RH to 35.degree. C.-80% RH. The constant-current regulated power supply has a pulse removing circuit for charging the moving photosensitive medium uniformly even when a few pin-holes exist in the photosensitive medium. A fiber element has a resistance between 4.5.times.10.sup.7 ohm and 1.times.10.sup.13 ohm when the fiber element has 1 denier in size and 1 mm in length, for charging the photosensitive medium and avoiding burning of the fiber element.