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. 06, 1998
Filed:
Dec. 20, 1995
Itaru Fukushima, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
The present provides a thermal head apparatus wherein temperatures of heat generation elements resulted from heat generation can be individually detected directly so that an abnormal condition of any heat generation element can be detected. A plurality of unit heat generation elements each formed from a resistor whose electric resistance value varies depending upon a temperature of itself are arranged in a row. A driving circuit is provided for each unit heat generation element and supplies an electric current to the unit heat generation element, and a temperature detection circuit is provided for each unit heat generation element and extracts, from the unit heat generation element, an electric signal which is obtained as a result of a variation of a resistance value caused by a variation in temperature of the unit heat generation element itself. An abnormal condition detection circuit is provided for each unit heat generation element and detects presence or absence of an abnormal condition of the unit heat generation element from an output of the temperature detection circuit.