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:
Jun. 06, 1995
Filed:
Mar. 25, 1993
NEC Corporation, Tokyo, JP;
Susumu Co., Ltd., Kyoto, JP;
Abstract
A thermal printer head comprises an array of heating elements (1-1.about.1-N) mounted on an insulating base member (20). Each of the heating elements is connected to a common voltage source (V) and has a temperature dependent electrical resistance. Electrically resistive elements (2-1.about.2-N) are respectively connected in series with the heating elements to form a plurality of series circuits. Current supply circuits (3-1.about.3-N, 4-1.about.4-N, 5, 6, 7-1.about.7-N, 14) are provided corresponding respectively to the resistive elements for selectively supplying a current to the series circuits in response to a sequence of print signals. A control circuit (8-11, 14) makes a determination whether a voltage developed across each resistive element is higher or lower than a prescribed threshold value and causes one of the current supply ciruits corresponding to the resistive element to control the current depending on the determination.