Development of the pneumatic valve with bimorph type PZT actuator

The benefits of the pneumatic valve with bimorph type piezoelectric (PZT) actuator are faster response times, low energy consumption, and the ability to be used in hazardous environments and field bus systems. In order to develop a PZT actuator system for the pneumatic valve, bimorph type PZT actuator (length: 25.2 mm, width: 7.2 mm, thickness: 0.5 mm) using the softener type PZT with constant of −220 × 10−12 C N−1, carbon plate as a shim and its controller circuit (operating voltage range: 24 V, built-in fast recovery diode) were suggested and investigated. Performance tests and characteristics analysis, such as displacement, force, hysteresis and frequency properties, were carried out. The displacement of the actuator measured at the end point was 63 μm, force of the actuator was 0.052 N and maximum operating frequency was 15 Hz. Also, characteristics of the pneumatic valve with PZT actuator were evaluated in a testing system. The results show that the suggested PZT actuator is suitable for pneumatic micro valve.