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:
Feb. 25, 1992
Filed:
Jul. 21, 1989
Beru Ruprecht GmbH & Co. KG, Ludwigsburg, DE;
Abstract
A glow plug for an air compressing internal combustion engine of the type having a tube which is closed at one end and connected to a plug housing on an opposite end with a wire filemant-like resistance element disposed in an insulating material within the tube and formed two series-connected resistance filaments, of which the rear resistance filament, serves as a regulating filament, having a higher positive temperature resistance coefficient than the front resistance filament, which serves as a heating filament, is improved so as to enable the heating up time to be reduced without adversely impacting upon the effective life of the glow plug. In accordance with various embodiments, this result is achieved through the use of, for example, special alloys for the material of the regulating filament which have a resitance at 1000.degree. C. that is greater than their resistance at 20.degree. C. by a resistance ratio over about 7.5:1, and preferably greater than 12:1, and in particular, about 14:1.