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:
Nov. 15, 1994
Filed:
Aug. 05, 1993
Takao Kumasaka, Takahagi, JP;
Yuzuru Shimazaki, Hitachi, JP;
Toru Miyasaka, Hitachi, JP;
Yukio Otome, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Koki Co., Ltd., Tokyo, JP;
Abstract
Each of a charging process on and after a second time is carried out by a charging means having a controlling electrode. The relationship between a controlling potential (Vg) applied to the controlling electrode of each charming means, the target surface potential (Vo) of a non-image portion of a surface of a photosensitive body and the direct current component potential (Vdc) of a developing bias potential in each developing process is satisfied by the formula, which is .vertline.Vo.vertline.>.vertline.Vdc.vertline..gtoreq..vertline.Vg.vertlin e.. Thereby the corona current ia supplied to flow sufficiently, it can rise the surface potential of a toner image portion of the surface of the photosensitive body after the re-charming without the excessive rise of the surface potential of the non-image portion of the photosensitive body. The surface potential of the toner image portion of the photosensitive body after the re-charging becomes to higher than the direct component potential (Vdc) of the developing bias potential, it can prevent from mixing the toners having other color.