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:
Aug. 28, 2007
Filed:
Apr. 26, 2006
Applicant:
Kouji Hori, Kuwana, JP;
Inventor:
Kouji Hori, Kuwana, JP;
Assignee:
Denso Corporation, Kariya, Aichi-pref, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01T 21/02 (2006.01);
U.S. Cl.
CPC ...
Abstract
The spark plug manufacturing apparatus includes a holding plate formed with a plurality of mounting holes penetrating from a front surface to a rear surface thereof for holding therein hollow tubular insulators of spark plugs, each of which is fitted therein with a center electrode and a metal stem provided with a terminal part, and is charged with a powder resistance material between the center electrode and the stem, and an electric furnace for heating the insulators held in the mounting holes of the holding plate. The holding plate is made of a ceramic material containing not less than 50 wt % of silicon nitride.