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. 28, 2020
Filed:
Sep. 23, 2015
Ngk Spark Plug Co., Ltd., Nagoya-shi, Aichi, JP;
Hironori Uegaki, Nagoya, JP;
Hirokazu Kurono, Nagoya, JP;
Toshitaka Honda, Nagoya, JP;
Hiroyuki Hazama, Nagoya, JP;
NGK SPARK PLUG CO., LTD., Nagoya-shi, Aichi, JP;
Abstract
A method for manufacturing an insulator for a spark plug includes a molding process of forming a cylindrical molded product having an axial hole that extends in a direction of an axial line, by means of injection molding using a mold that has a columnar cavity therein and a bar-shaped member disposed in the cavity and extending in the direction of the axial line. In this method, the molding process includes an injection step of injecting a material containing a ceramic. In the injection step, the material is injected into the cavity from a plurality of injection openings that are opened at an inner circumferential surface, of the mold, that forms the cavity. The plurality of injection openings include two or more injection openings located at different positions in the direction of the axial line, or two or more injection openings located at different positions in a circumferential direction.