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, 1999
Filed:
Jan. 26, 1994
Applicant:
Inventors:
Takahiro Suzuki, Nagoya, JP;
Kouji Okazaki, Nagoya, JP;
Yoshiaki Matsubara, Nagoya, JP;
Mamoru Kodera, Nagoya, JP;
Assignee:
NGK Spark Plug Co., Ltd., Aichi, JP;
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
313119 ; 313142 ; 313143 ;
Abstract
A threaded portion is formed on a metal shell of a spark plug. Within a mounting base of the metal shell, a pressure sensor is arranged in such a direction that it generates an electrical signal in response to a variation in a tightening load of the spark plug. A slit is formed as a pressure-introducing channel along an axis of the spark plug in the threaded portion of the metal shell so that the slit is communicated with an interior of the mounting base.