METAL SHEATH GLOW PLUG

摘要

A glow plug (10) which includes an annular metal shell (12), thermally conductive tubular sheath (20), electrode (22), resistance heating element (24), and electrically insulating, thermally conductive powder (26). A metallic seal (28) is disposed in an open end of the sheath (20) in sealing engagement with the electrode (22). An insulating layer (54) is formed on the outer surface of the electrode (22) so as to prevent electrical conductivity between the metal seal (28) and the electrode (22). An optional secondary metal layer (56) may be disposed between the insulating layer (54) and the metal seal (28).