| 摘要 |
PROBLEM TO BE SOLVED: To provide a glow plug to prevent the occurrence of a problem on adhesion of carbon, detect an ion current with high precision, and have excellent durability. SOLUTION: A glow plug comprises a housing 4; and a body 10 supported thereat. The body 10 comprises an insulating body 11; an energization hat generating body 2 and a pair of lead wires 21 and 22, which are arranged at the internal part thereof; an electrode 3 for detecting ion. The electrode 3 for detecting ion is provided with an exposing part 30 exposed from the insulating body 11 in a manner to be exposed to flame. The exposing part 30 has a polishing part 6 polished into surface roughnes's Rz (ten points average coarseness) of 0.1-30μm. An area of the exposing part 30 is 1×10<-6> -0.5cm<2> .
|
