| 摘要 |
PURPOSE:To cool effectively an exhaust valve featuring variable exhaust timing for a two-cycle engine by fixing one of ends of a thermal conductor such as a heat pipe or the like on the exhaust valve with the other end exposed outside the engine. CONSTITUTION:The rotatable exhaust valve 24 is located at the exhaust port 23 on the side of the cylinder in which the poston connected to the crankshaft 4 through the connecting rod 3 can slide freely. Exhaust timing is adjustable at the exhaust port 23 by rotary motion of the exhaust valve 24. For this type of engine, one of ends of a heat pipe 28 which constitutes a thermal conductor is fitted at the center of one of the shaft ends of the exhaust valve 24, while the other end of the heat pipe 28 is exposed outside the engine. The heat pipe 28 is filled with operating fluid and the inside wall of the hermetically sealed pipe body 29 is lined with porous wick 30, and many fins 31 are provided on the heat dissipating end of the pipe body 29. |
