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:
Jan. 17, 2012
Filed:
Feb. 13, 2009
Takatsugu Iwami, Tokyo, JP;
Yoshie Tsuchida, Osaka, JP;
Mitsutoshi Kichise, Osaka, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An image forming apparatus includes an image carrier; a movable endless belt member forming a nip between the image carrier; and a transfer roller made of metal contacting the belt member at a region corresponding to the nip. At the nip, a toner image on the image carrier is transferred onto the belt member. The transfer roller slidably rotates in bearings supporting its shaft. Members having a higher friction coefficient than that of the transfer roller are provided at end portions of the transfer roller. F>Fand F>Fare satisfied, where Fis a maximum static friction between the transfer roller and the belt member, Fis a dynamic friction between the transfer roller and the belt member, Fis a maximum static friction between the shaft of the transfer roller and the bearings, and Fis a dynamic friction between the shaft of the transfer roller and the bearings.