| 摘要 |
In an ignition plug (10), the volume V1 of a portion of an insulator (200), which projects from a metallic shell (300) to a front side (-Z), is equal to or greater than 45 mm 3 ; and an expression 0.18 ‰¤ V2/V1 ‰¤ 0.37 is satisfied, where H is a length along which the insulator (200) projects from the metallic shell (300) to the front side in an axial direction (Z), and V2 is a volume of a portion of the insulator (200), which projects from a front end of the insulator (200) along a length H/2 in the axial direction (Z). |
