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. 14, 2017
Filed:
Mar. 18, 2016
Tatsuya Ohsugi, Kanagawa, JP;
Kenji Sugiura, Kanagawa, JP;
Hirokazu Ishii, Tokyo, JP;
Hiroyoshi Haga, Kanagawa, JP;
Naohiro Kumagai, Kanagawa, JP;
Seiichi Kogure, Kanagawa, JP;
Takehide Mizutani, Tokyo, JP;
Junpei Fujita, Kanagawa, JP;
Yuuji Wada, Kanagawa, JP;
Kazuki Yogosawa, Kanagawa, JP;
Naoto Kochi, Kanagawa, JP;
Tatsuya Ohsugi, Kanagawa, JP;
Kenji Sugiura, Kanagawa, JP;
Hirokazu Ishii, Tokyo, JP;
Hiroyoshi Haga, Kanagawa, JP;
Naohiro Kumagai, Kanagawa, JP;
Seiichi Kogure, Kanagawa, JP;
Takehide Mizutani, Tokyo, JP;
Junpei Fujita, Kanagawa, JP;
Yuuji Wada, Kanagawa, JP;
Kazuki Yogosawa, Kanagawa, JP;
Naoto Kochi, Kanagawa, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An image forming apparatus includes a plurality of image bearers, a transfer bias member, and a power source. When the transfer bias member transfers a color toner image onto a recording sheet, a second peak value of a peak-to-peak of a transfer bias, which is smaller than a first peak value of the peak-to-peak in an electrostatic force to move toner from the image bearers or an intermediate transfer body to the recording sheet, is zero or has a first polarity to generate the electrostatic force in a transfer direction to move toner from the image bearers or the intermediate transfer body to the recording sheet. When the transfer bias member transfers a monochromatic toner image including only black toner onto the recording sheet, the second peak value is zero or has a second polarity to generate an electrostatic force in an opposite direction to the transfer direction.