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:
Aug. 21, 2001
Filed:
Dec. 12, 1997
Masahiko Umezawa, Kawasaki, JP;
Shinichi Omo, Kawasaki, JP;
Akira Kuronuma, Kawasaki, JP;
Takayuki Murata, Kawasaki, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
When the sub-heaters of recording heads are PWM controlled in a low-temperature environment, temperatures of the recording heads are respectively detected by temperature sensors. The number of recording heads to be heating controlled is determined from the detected recording head temperatures, and a maximum duty ratio of a pulse train supplied to the sub-heater corresponding to the recording head to be heating controlled is determined in accordance with the determined number of the recording heads, so that supply timings of pulse width controlled pulse trains supplied to the sub-heaters corresponding to the recording heads to be heating controlled are not overlapped.