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. 12, 2016
Filed:
Aug. 20, 2014
Canon Kabushiki Kaisha, Tokyo, JP;
Takahiro Aida, Tokyo, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
An embodiment of this invention is directed to discriminating between an ink present state and a bubble state and accurately determining the presence/absence of ink in residual ink detection. A printing apparatus measures the voltage between two electrodes in an ink tank based on an electric current supplied to one of the two electrodes, and compares the measured voltage with a first threshold voltage. When the measured voltage is lower than the first threshold voltage, the measured voltage is compared with a second threshold voltage lower than the first threshold voltage. According to results of these two comparisons, control is performed to supply the electric current, re-measure the voltage between the two electrodes, and re-inspect a residual ink amount. In a case where accurate determination is suspected, the presence/absence of ink is determined by re-inspection.