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. 13, 1998
Filed:
Jul. 24, 1996
Eiichi Sasaki, Sagamihara, JP;
Yutaka Shio, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
In a color image forming apparatus, a plurality of color images of component colors are combined to form a full color image. These images of the component colors are overlapped on an intermediate recording medium, and are then transferred to a transfer medium. Control circuitry reduces the amount of time required to form the component color images on the intermediate transfer medium, and to prevent an abnormality such as an out-of-phase or pull-out of a closed loop control circuit for controlling such a formation of the component color images. This may be achieved by abruptly changing a phase of a motor synchronizing signal. Further, for a period of time after the motor synchronizing signal is abruptly changed, a gain of an amplifier in the motor control circuit can be reduced, an abnormality detection in the motor control circuit can be reduced, the motor control circuit can be placed in an open loop state, or an addition or subtraction signal can be input to the closed loop motor control circuit. This specified period can also be detected based on a feedback including a rotational phase of a polygon motor formed as part of a unit for writing the individual component color image signals.