DEVELOPMENT OF A PNEUMATIC ON/OFF CONTROL VALVE USING A PZT FLIGHT HAMMER

Abstract

This paper deals with the development of a pneumatic on/off valve driven by impulsive force of a multilayer PZT actuator. The displacement of the actuator is so small that it is necessary to design an amplifying mechanism. However, it subtracts the advantages of this actuator. On the other hand, the actuator can snap off a contacting small object like a hammer when the voltage is applied rapidly. This type of action is called a flight hammer. Using this action we hav developed an on/off valve with a nozzle-flapper mechanism, which is normally closed by the air pressure and is opened for a short time by the PZT actuator with the help of the spring force. The application of this valve is to blow off small objects by the air pulse flows that are generated by the on/off action of the valve. The air jet could blow up a small steel ball up to 20cm in height.