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. 03, 1980
Filed:
Feb. 17, 1976
William H Rhodes, Lexington, MA (US);
Paul O Haugsjaa, Acton, MA (US);
John C Gustafson, Waltham, MA (US);
GTE Laboratories Incorporated, Waltham, MA (US);
Abstract
An electric gas ignitor is disclosed having a gas igniting fiber comprising a core of conductive refractory material and an outer, high strength, oxidation resistant coating. One aspect of the invention concerns a primary current path defined by at least a portion of the fiber core and comprising a material having a highly uniform resistance per unit length. A substantially uniform temperature distribution is thereby promoted on the fiber surface and the formation of localized 'hot spots' is inhibited. The primary current path is preferably an anisotropic material having a preferred crystal orientation which uniformly conducts electricity along the fiber length. A second aspect of the invention is directed to the inclusion of a diffusion-barrier material between the fiber core and the oxidation-resistant coating to prevent diffusion of the core and coating, which changes the fiber operating temperature and decreases its operating life. The diffusion-barrier material is preferably refractory, closely packed, dense and, more perferably, is an anisotropic material having its preferred crystal orientation in a direction which inhibits the diffusion while forming the primary current path of the fiber.