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:
Apr. 27, 1993
Filed:
May. 04, 1992
Takashi Aota, Saitama, JP;
Jidosha Kiki Co., Ltd., , JP;
Abstract
A sheath heater is formed by connecting first and second helical resistive elements having different positive resistance temperature coefficients in series, and incorporating the first and second resistive elements in a sheath such that the two resistive elements are embedded in a heat resistance electric insulating powder. The sheath diameter of a sheath portion in which the first resistive element is embedded is set to be smaller than that of a sheath portion in which the second resistive element is embedded. In addition, the first and second resistive elements are connected to each other, through connecting ends extending to be located within the outer diameter of the first resistive element, within a gap larger than the sheath diameter of the sheath portion in which the first resistive element is embedded.