Glow plug for use in motor, has ceramic glow pin provided with cylindrical main section and end section, where inner diameter of protective tube is provided from certain value to reduced valve from outside of housing

摘要

The glow plug has a ceramic glow pin (3) provided with a cylindrical main section and an end section (2a). The thickness of the glow pin decreases between the main section and the end section. An inner diameter of a protective tube (2) is provided from a value to a reduced valve from outside of a housing (1). The former value is larger than outer diameter of the main section of the glow pin. The reduced value is smaller than outer diameter of the main section of the glow pin.