| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an ignition coil for an internal combustion engine in which the seal structure having a water-proof function and a ventilating function is formed by a simple structure. SOLUTION: A case 100 of an ignition coil 2 comprises a cylindrical part 106 inserted in a plug hole 4 and a head part 107 provided on one end of the cylindrical part 106. The space between the head part 107 and an engine head cover 3 is sealed with an annular packing 115 installed on the outside of a projected part 110 projected from the cylindrical part 106. A first gap 111 communicated with the plug hole 4 is formed between the axial groove 110a formed on the projected part 110 and the inner peripheral end part of the packing 115. The lower end surface 107a of the head part 107 is provided with a radial groove 110b, one of which is connected to the axial groove 110a, the other end thereof being opened to the outer peripheral wall of the head part 107, and a head passage 112 is formed between the radial groove 110b and the upper surface 115a of the packing 115. The plug hole 4 is opened to the air by the first gap 111 and the head passage 112.</p> |
