| 摘要 |
PURPOSE:To obtain good valve performance and at the same time eliminate imcomplete combustion of mixed gas by constructing the valve structure of the spark plug by using a ring-shaped member through which air can pass and a sheet of pressure resisting, heat resisting and flexible valve member, which is placed in the ring- shaped member. CONSTITUTION:In spark plug 1, its screw part 2 is screwed into fastening screw hole 3 of the engine, and valve structure 5 is provided between holding member 4, made of metal, and the opening of fastening screw hole 3. Here, valve structure 5 permits generally the passage of a small amount of air. It consists of ring-shaped member 6, having inward-directed flange 6a in its lower part, and a thin disk- shaped valve member 7, having a hole in its center, whose outer circumference is supported by its inner wall. When valve member 7 is fixed to ring-shaped member 6, step 6c is formed in advance on the inner wall of ring-shaped member 6, so that valve member 7 can be maintained horizontal in contact with the top part of ring- shaped protection 6b, and valve member 7 is mounted on step 6c. |
