Development of 2-position 3-port control valve with self-holding function

Recently, force feedback devices in virtual reality and power assisted nursing care systems have received much attention and active research. In such a control system, an actuator and a driving device such as a control valve are mounted on the human body. In this condition, the size and weight of the valve become serious problems. At the same time, the valve should be operated with lower energy consumption because of using a limited electrical power. The typical electro magnetic solenoid valve drives its spool using a larger solenoid to open the orifice. The complex construction of the valve for sealing makes its miniaturization and the fabrication of a low cost valve more difficult. In addition, the solenoid in the valve consumes more electrical power while the valve is kept opening. The purpose of our study is to develop a small-sized, lightweight, lower energy consumption and flexible control valve that can be safe enough to mount on the human body at a lower cost. In our pervious study, we proposed and tested the control valve that can open using a vibration motor. We also proposed and tested a new type of fluid control valve with a self-holding function using a permanent magnet ball in a check valve, a cylindrical magnet and two solenoids. In this study, we propose and improve the valve so as to make 2 positions and 3 ports control valve with self-holding function. As a result, we confirm that the tested valve can realize both functions of supply and exhaust. We also find that the valve has a function of overlap by using the time lag of moving cylindrical magnet.