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:
Oct. 12, 1993
Filed:
May. 15, 1990
Akihiko Takeuchi, Yokohama, JP;
Takayasu Yuminamochi, Yokohama, JP;
Hiroto Hasegawa, Kawasaki, JP;
Koichi Tanigawa, Tokyo, JP;
Yasumasa Ohtsuka, Yokohama, JP;
Hiroki Kisu, Ichikawa, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An image forming apparatus includes a movable image bearing member; an image forming device for forming a toner image on the image bearing member; an image transfer device for transferring the toner image onto a transfer material at a transfer position, the transfer device including a rotatable member contactable to such a side of the transfer material as is opposite from a side contactable to the image bearing member and an electric field forming device for forming an electric field between the image bearing member and the rotatable member; wherein the electric field forming device forms a first electric field effective to transfer the toner from the rotatable member to the image bearing member and a second electric field which is opposite in a direction from the first electric field during a period in which the transfer material is absent at the transfer position, wherein each of the first and second electric fields is formed at least for a period required for the entire surface of the rotatable member passes through the transfer position.