Method for manufacturing spark plug
US9496687B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 2012 |
| Grant date | Nov 15, 2016 |
| Priority date | — |
| Expiry date | Dec 12, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01T13/58
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for manufacturing a spark plug includes an assembling step of assembling an insulator into a metallic shell by insertion of the insulator into the metallic shell from an axially rear end opening portion of the metallic shell. The assembling step includes a displacement restricting step of restricting a relative positional displacement between the metallic shell and the insulator in a radial direction intersecting with the axial direction so as to reduce eccentricity between the axis of the metallic shell and the axis of the insulator to a predetermined value or less, while allowing a relative positional displacement between the metallic shell and the insulator in the axial direction. In the assembling step, whether or not the insulator is cracked in the assembling step is judged by detecting acoustic emission from the insulator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.