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:
Apr. 24, 2012
Filed:
Jun. 17, 2008
Hiroyasu Nomura, Tokyo, JP;
Makoto Shihoh, Kanagawa-ken, JP;
Hiroyasu Nomura, Tokyo, JP;
Makoto Shihoh, Kanagawa-ken, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
In order to prevent, in an operation for circulating liquid, an ejection port from sucking air or the ejection port from pushing out liquid, the subtank for temporally storing ink to be supplied to the ink jet head includes the air communication passage opened or closed by the air communication valve. The ink jet head is communicated with the subtank by the first passage and the second passage to constitute one circulation passage. In order to circulate the ink in the subtank into the common liquid chamber, the main pump is energized while the air communication valve is being closed. When the circulation operation is stopped, the air communication valve is opened immediately after the stoppage of the main pump, thereby eliminating the differential pressure between the common liquid chamber and the subtank within a short period of time.