Abstract: A new kind of high-speed on/off valve is recommended. It has two-stages structure, in which a special valve spool and a giant magnetostrictive actuator as electric- mechanism switchover sets are used for the pilot stage, so the switch speed and frequency of the valve are greatly increased. The second stage of the valve has a ball valve, so its sealing property and respond speed is well. The result of experiment shows that the time of switch is 8～10 ms and the maximum flow has get to 120 L/min. Comparing with the piezoelectric high-speed on-off valve, this valve can get a more output flow and the fall of con-sume of electric power and is a kind of up-and-coming high speed on-off valve.

Key words: Giant magnetostrictive actuator, High-speed on-off valve, PWM