Small size pneumatic valve for smooth flow control using PZT vibrator

Pneumatic actuators have the potential to be downsized because they have simple structure. However, many control devices that can control pneumatic actuators continuously have large volume and weight. We have designed a flow-control valve driven by PZT vibrator. This control valve has small volume and low weight, and it can control air flow smoothly. This valve is suited to control small pneumatic actuators. The flow control valve that we propose uses resonance vibration with a PZT vibrator. The valve consists of an orifice plate, a PZT vibrator and iron particles that work as the poppet. From experimental flow quantity evaluation, this control valve controls air flow smoothly with low hysteresis at a large flow rate. In addition, this flow control valve achieves a maximum flow rate of 65 L/min under air pressure of 0.70 MPa. The results show that the valve has high controllability and can control a relatively large flow rate compared to its weight and size.