公开(公告)号：US20170250523A1

公开(公告)日：2017-08-31

申请号：US15521740

申请日：2015-09-23

Applicant: NGK SPARK PLUG CO., LTD.

Inventor： Hironori UEGAKI ,  Hirokazu KURONO ,  Toshitaka HONDA ,  Hiroyuki HAZAMA

IPC: H01T13/20 ,  H01T21/02 ,  B28B7/18 ,  B28B1/24 ,  B28B13/02

CPC classification number: H01T13/20 ,  B28B1/24 ,  B28B7/18 ,  B28B13/02 ,  B28B13/021 ,  H01T21/02

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.

公开(公告)号：US20190131775A1

公开(公告)日：2019-05-02

申请号：US16091144

申请日：2017-01-13

Applicant: NGK SPARK PLUG CO., LTD.

Inventor： Yusuke KAWASHIMA ,  Hiroyuki HAZAMA

IPC: H01T13/32 ,  H01T21/02

CPC classification number: H01T13/32 ,  H01T13/20 ,  H01T13/39 ,  H01T21/02

Abstract: Disclosed is a spark plug having a ground electrode in which a weld zone is formed a tip and electrode base. The weld zone has: a back region exposed at an opposite surface of the electrode base; a joint region at which the tip is joined; and a connection region connects the joint region and the back region without being exposed at side surfaces of the electrode base. In a cross section of the ground electrode taken through the side surfaces of the electrode base along a plane passing through the centers of the top and bottom surfaces of the tip, a value of a width of the top surface of the tip being divided by a width of the facing surface of the electrode base is greater than 0.3, and a maximum width of the connection region is larger than a width of the back region.