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. 04, 2000
Filed:
Jul. 13, 1998
Chin-Fong Chang, Morris Plains, NJ (US);
Richard Dale Taylor, Findlay, OH (US);
Lee Randall Franz, Findlay, OH (US);
Edgar Arnold Leone, Randolph, NJ (US);
AlliedSignal Inc., Morristown, NJ (US);
Abstract
A spark plug and method of making same, wherein the spark plug includes a platinum alloy tip portion which takes the form of a rivet or a sphere. The tip portion is annealed in an annealing furnace at a temperature between about 700.degree.-1400.degree. C. for a time between about 5-30 minutes. The annealed tip portion is then resistance welded to an electrode of the spark plug. The annealing provides the tip portion with added resistance to corrosion and attack by lead. Preferred embodiments of the spark plug tip material comprise 80% platinum--20% rhodium; 80% platinum--20% iridium; 96% platinum--4% tungsten; and Pt (bal)-Ir(a)%-W(b)%, where 'a' ranges from about 15 to 19 percent by weight, 'b' ranges from about 1 to 4 percent by weight, and the balance is comprised of platinum and incident impurities, and wherein the sum of iridium and tungsten present ranges from about 16 to 19.