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:
May. 07, 2019
Filed:
Oct. 16, 2017
Canon Kabushiki Kaisha, Tokyo, JP;
Jiro Kinokuni, Abiko, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An image forming apparatus includes an image bearing member, a charging roller, a toner image forming portion, a voltage source, a detecting member, a controller, and a test executing portion configured to execute an operation in a test mode in which in a period in advance of the image forming period, a plurality of test AC voltages having a test peak-to-peak voltage with different frequencies are successively applied to the charging roller and alternating currents are detected by the detecting member. The test executing portion sets a predetermined peak-to-peak voltage on the basis of a specific frequency which is a maximum frequency at which a relationship between the frequencies and the alternating currents acquired in the operation in the test mode maintains linearity.