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:
Sep. 21, 2004
Filed:
Jul. 19, 2002
Rudolf Pollner, Bamberg, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
The seal between the insulator and the center electrode is to be improved in a spark plug for an internal combustion engine comprising a shell ( ), an insulator ( ) located in the shell and composed of a sintered ceramic material, as well as a center electrode ( ) and a terminal stud ( ) that have an electrically conductive connection with each other and are located in the insulator. For this purpose, it is provided that a cermet ( ) abuts the center electrode, the ceramic phase of which is composed of the same or a similar material as the insulator, and the metallic phase of which is composed of a material having good electrical conductivity. Since the material properties of the cermet are similar to those of the insulator—the thermal expansion, in particular, is same—a particularly good seal is created between the cermet and insulating body.