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. 20, 1986
Filed:
Apr. 18, 1984
Kazumi Ishima, Kashiwa, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A circuit for controllably driving a heater in order to speed up temperature elevation at a buildup stage of a liquid which is to be maintained at a predetermined temperature heated by the heater, particularly ink in an ink jet printer. A voltage developed by doubling an output voltage of an atmospheric temperature sensor by an amplifier is compared with a reference voltage, which is adapted to decide power to be supplied to the heater in the event of a buildup of the ink temperature. A temperature-sensitive element responsive to an atmospheric temperature has a temperature coefficient which is double the temperature coefficient of a temperature-sensitive element responsive to a heater temperature. The output voltages of the two elements are weighted by a same amount and then added together, the summation output being compared with the reference voltage.