Spark plug with integral retainer nut
US5697334A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 16, 1996 |
| Grant date | Dec 16, 1997 |
| Priority date | — |
| Expiry date | Feb 16, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01T13/467
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A spark plug (11) having a center conductive path (21) with a cylindrical body having a tip (33, 51, 77) at one end and a terminal (23) near the other end has an insulator (41, 45) radially surrounding the center electrode and a substantially cylindrical body with at least first and second diameter sections separated by a shoulder (29). A ground shield (37) surrounds the insulator first diameter section and including near one end a frustoconical section (31) juxtaposed with the insulator shoulder. There is a ground electrode (55, 57, 73) near the other end having a portion thereof (53, 75) aligned with the center electrode tip to form a spark gap. An annular retainer (59) surrounds the insulator second diameter section and including a threaded portion (61) threadedly engaging the threaded portion (17) of a generally cylindrical opening in the head of an internal combustion engine. The retainer includes a frustoconical portion (63) overlapping the ground shield frustoconical section and juxtaposed insulator shoulder securing the ground shield and retainer together with the insulator captured therebetween. The annular retainer has a sidewall thickness in the region of the threaded po…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.