Abstract
The benefits of the electro-pneumatic regulator 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. However, the PZT actuator has a hysteresis nonlinearity due to the ferroelectric characteristics of the PZT element. This causes problems in the system pressure control characteristics and deteriorates the performance of the system. This paper presents a new mechanism for the proportional pressure control which is accomplished by electro-pneumatic regulator with two PZT actuators. Proportional pressure control technique is very important because that can derive improvement of product quality and driving ability in the pneumatic system. Solenoid actuator method for pressure control is widely used but this actuator has a high power consumption characteristics. So new actuator is required for the energy saving. In this study, PZT actuator for the pressure control was fabricated and experimented instead of the conventional type solenoid actuator. Operating voltage of 24[V], maximum pressure of 0.1[MPa] and maximum flow of 1.5[lpm] were gotten from the experimented PZT actuator. Experiments for the new control mechanism of the electro-pneumatic regulator were operated under the input condition of 0.1[MPa] and it was confirmed that this mechanism has a good control characteristics to the response sensitivity and hysteresis.
