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:
Oct. 25, 1994
Filed:
May. 07, 1992
Toshiyuki Hanada, Kawaguchi, JP;
Mayumi Takata, Tokyo, JP;
Naoki Yamazaki, Tokyo, JP;
Isao Morooka, Hachioji, JP;
Kazuhiko Harazaki, Hachioji, JP;
Daito Communication Apparatus Co., Ltd., Tokyo, JP;
Abstract
A PTC device has two electrodes affixed to opposed surfaces. The electrodes consist of a metal foil having a conductive layer on their surfaces that contact the PTC material. The conductive layer has a thermal coefficient of expansion intermediate between the thermal coefficients of expansion of the metal foil and the PTC material. The intermediate value of the thermal coefficient of expansion of the conductive layer prevents peeling of the electrodes off the PTC element due to the variation of the temperature of the PTC device resulting from repeated voltage applications. In addition, improved adhesion of the electrodes to the PTC material reduces resistance changes after repeated temperature cycling.