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. 21, 2013
Filed:
Sep. 19, 2011
David Shau Chew Wang, Taipei, TW;
Yi an Sha, Xindian, TW;
Kuo Chang Lo, New Taipei, TW;
Tai Kuang Hei, Xinpu Township, Hsinchu County, TW;
David Shau Chew Wang, Taipei, TW;
Yi An Sha, Xindian, TW;
Kuo Chang Lo, New Taipei, TW;
Tai Kuang Hei, Xinpu Township, Hsinchu County, TW;
Polytronics Technology Corp., Hsinchu, TW;
Abstract
An over-current protection device includes two metal foils and a PTC material layer laminated therebetween. The PTC material layer has a volume resistivity between 0.07 Ω-cm and 0.32 Ω-cm. The PTC material layer includes a crystalline polymer, a conductive ceramic carbide filler of a particle size between 0.1 μm and 50 μm and a volume resistivity less than 0.1 Ω-cm, and a carbon black filler. The weight ratio of the carbon black filler to the conductive ceramic carbide filler is between 1:90 and 1:4. The conductive ceramic carbide filler and the carbon black filler are dispersed in the crystalline polymer. The resistance ratio R/Ri is between 3 and 20.