Patent · US Expired

Anti-carbon fouling spark plug

US6166481A · kind A · utility

7Cited by
6References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 11, 1999
Grant dateDec 26, 2000
Priority date
Expiry dateFeb 11, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01T13/38
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A spark plug (100) includes a ground electrode (125), a firing electrode (115), an insulator core (105) having an insulator core nose (120), and an outer shell (110) surrounding the insulator core (105). The improvement includes the insulator core nose (120) including a high temperature glaze applied to an outer surface of the insulator core nose (120) and the high temperature glaze composition. The composition includes, by weight: PA1 (i) between about 72 and 84% SiO.sub.2 ; PA1 (ii) between about 10 and 20% Al.sub.2 O.sub.3 ; PA1 (iii) between about 2.0 and 2.5% K.sub.2 O; PA1 (iv) between about 0.50 and 0.65% Na.sub.2 O; PA1 (v) between about 3.0 and 5.5% CaO; PA1 (vi) between about 0.1 and 0.25% MgO; and PA1 (vii) the remainder impurities.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.