| 摘要 |
PURPOSE:To reduce a noise and a friction loss, by constituting both suction and exhaust valves with a hydraulic cylinder unit, while setting up a rotary valve in position between this unit and a pump, opening or closing the valve in a way of adding hydraulic pressure to an oil chamber of the unit alternately, and miniaturizing a cylinder head. CONSTITUTION:Each piston 12 is isntalled in a suction valve 5 and an exhaust valve 6 and this piston 12 is housed inside a cylinder 11 whereby a hydraulic cylinder unit 10 is formed up. Both oil chambers S1 and S2 of this unit 10 is slidable in an axial direction and connected to a hydraulic pump P via a hydraulic selector valve V to be rotated in synchronization with an engine. The selector valve V is provided with a rotary valve 22 having notches 22a, 22b and 22c opening or closing oil passage 21a, 21b and 21c, and slidden in an axial direction on demand by a fork 23, controlling on-off timing of the valve. According to this method, a cylinder head pat is miniaturized and reduction in noise and friction loss power is well promoted and, what is more, valve on-off timing and valve lift are controllable. |
