Spark plug having improved ground electrode orientation and method of forming
US9893496B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 26, 2017 |
| Grant date | Feb 13, 2018 |
| Priority date | — |
| Expiry date | Jan 26, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01T21/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of manufacturing a spark plug (20) for being threaded into a cylinder head (28) of an internal combustion engine is provided. The spark plug (20) includes a shell (24) with threads (26) disposed at a predetermined rotational position (a) relative to a shell outer surface (64) and ground electrode (34). The position of the threads (26) relative to the ground electrode (34) places the ground electrode (34) in a desired position in the combustion chamber (22) and relative to components of the engine, thus allowing the ground electrode (34) to provide a robust and reliable ignition. When multiple spark plugs (20) are formed, the threads (26) in each of the shells (24) are repeatedly and accurately formed at the predetermined rotational position (α) by locating the ground electrode (34), threads (26), and dies (76) of a thread forming apparatus (102) in specific locations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.