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:
Mar. 02, 2004
Filed:
Mar. 23, 2002
Heinz Geier, Leonberg, DE;
Rudolf Pollner, Bamberg, DE;
Imke Koengeter, Stuttgart, DE;
Ulrich Eisele, Stuttgart, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A glass ceramic, for use as a resistor or a gas-tight glass ceramic solder for use in a spark plug, includes a fused seal of a starting glass fused from a starting mixture containing SiO , Al O , TiO and CaO, the fused seal including crystalline phases in at least some areas. A method for producing such a glass ceramic provides for the starting glass to be processed in a first method step to form a starting material, which is heated for a first period of time in a second method step from a starting temperature, which is below the softening temperature of the starting glass, to a fusion temperature, which is above the softening temperature of the starting glass, and is kept at that temperature for a second period of time and finally is cooled again. A spark plug may include a terminal stud and a center electrode, which are electrically connected across a resistor that is formed in at least some areas by the glass ceramic.