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:
Jun. 18, 1991
Filed:
Oct. 31, 1989
Yasuhiro Kusuda, Osaka, JP;
Minolta Camera Kabushiki Kaisha, Osaka, JP;
Abstract
An image forming apparatus arranged to develop an electrostatic latent image formed on an electrostatic latent image holding member, and including a developing sleeve rotatably provided to confront the electrostatic latent image holding member, a sleeve driving device for rotating the developing sleeve, a magnet roller provided within the developing sleeve and having a plurality of magnetic poles, a magnet roller driving device for rotating the magnet roller through a predetermined angle, with the magnet roller driving device being arranged to rotate the magnet roller between a first state where its magnetic pole confronts the electrostatic latent image holding member and a second state where an intermediate portion between neighboring magnetic poles confronts the electrostatic latent image holding member, and a control unit for controlling the sleeve driving device and the magnet roller driving device in such a manner as to rotate the magnetic poles of the magnet roller from the first state to the second state after stopping rotation of the developing sleeve when the developing function is to be completed. A bias voltage is applied to the developing sleeve such that the amount of bias voltage applied to the developing sleeve is change from a first value to a second value upon stopping rotation of the developing sleeve or following rotation of the magnet roller, the first value being closer to zero than the second value.