| 摘要 |
[Means for Solution] An ignition plug 1 includes a tubular metallic shell 3 and an insulator 2 provided internally of an inner circumference of the metallic shell 3 and having a rear trunk portion 10 formed at a rear end portion thereof and protruding in an exposed condition from the rear end of the metallic shell 3. The ignition plug 1 is configured such that the metallic shell 3 and the insulator 2 are fixed together by means of a crimped portion 20 provided at a rear end portion of the metallic shell 3 and bent radially inward. The ignition plug 1 is utilized for detecting ionic current. The ignition plug 1 has an electrically insulative filling member 31 which fills a space SP formed between the crimped portion 20 and the insulator 2. The filling member 31 covers at least a portion of the outer circumferential surface of the rear trunk portion 10 along the entire circumference and the entirety of a rear end surface 20A which is a portion of the outer surface of the crimped portion 20 and is visible from the rear side with respect to the direction of an axial line CL1. |
