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:
May. 08, 2001
Filed:
Jun. 10, 1999
NGK Spark Plug Co., Ltd., Nagoya, JP;
Abstract
In a spark plug, a main air gap (A) is formed between a parallel ground electrode (,) and the end face of a central electrode (,), a semi-surface gap (B) is formed between the end face (,C) of a semi-surface ground electrode (,) and the side face (,A) of the central electrode (,) and a semi-surface air gap (C) is formed between the end face (,C) and the side face (,E) of insulator. In addition, difference in a level E between the height of the lower end face (,D) of the insulator (,) and the height of the upper edge (,B) of the end face,C of the semi-surface ground electrode,is E≦+0.7 mm, the distance B of the semi-surface gap (B) is longer than the distance A of the main air gap (A) and the distance C of the semi-surface air gap (C) and the insulator is shorter than the distance A of the main air gap (A).