| 摘要 |
PROBLEM TO BE SOLVED: To provide a spark plug for temperature measurement which can be restored to a usable state fast and inexpensively since exchange of a sheathed thermocouple can be easily carried out when the sheathed thermocouple falls in an operation failure. SOLUTION: In the spark plug 1 equipped with a bottomed cylindrical center electrode 8 mounted on an axial hole 6a of an insulator 6, and the sheathed thermocouple 11 installed at an insertion hole 47 of the center electrode 8, the sheathed thermocouple 11 is detachably coupled with and fixed to the center electrode 8, and that, a fixation position of the sheathed thermocouple 11 is set so that a bottom part of the insertion hole 47 and a tip part 11a of the sheathed thermocouple 11 have a gap of 0.05 mm or more and 1.00 mm or less. COPYRIGHT: (C)2011,JPO&INPIT
|
