| 摘要 |
PURPOSE:To enhance the efficiency of exhaust, by providing a third valve in addition to intake and exhaust valves, and by communicating the port for the third valve with the intake and exhaust ports in synchronization with the operation of the engine. CONSTITUTION:A third valve 11 is formed in an engine cylinder 2 in addition to intake and exhaust valves 4, 6, and the port 10 for the third valve 11 are communicated with an intake passage 12 communicated with an intake pipe 7 and an exhaust passage 13 communicated with an exhaust pipe 8, selectively by means of a rotary change-over valve 17. Upon suction stroke of the engine the intake valve 4 is opened while the rotary change-over valve 17 communicates the intake passage 12 with the port 10, and suction is effected in the engine cylinder in association with the opening of the third valve 11. Upon exhaust stroke of the engine the exhaust valve 6 is opened while the rotary change-over valve 17 communicates the port 10 with the exhaust passage 13 so that the exhaust is effected in the cylinder in association with the opening of the third valve 11. |
