Unconstrained pneumatic on-off poppet valve driven by piezoelectric actuator

A radically different principle from that of conventional pneumatic valves is presented, whereby a valve is actuated by piezoelectric actuators (PEAS) with a range of vibration modes. This on/off control valve has an unconstrained poppet structure and therefore the assembling procedures become much easier for miniaturized valves. In this paper, a mathematical model of an unconstrained valve’s internal system including the mechanical behavior of PEAS along with air flow dynamics through nozzles is proposed. Also, comparisons between actual characteristic and simulated results of this on off poppet valve are presented. In practical application, this valve is able to operate at pressure up to 0.5 MPa and has an average flow rate of maximum 27 L/min for orifice with diameter of 0.8 mm. Finally, the valve is tested with different levels of input voltage and frequency to observe its peculiar flow characteristics.