抄録
In this study, the force and velocity control of hydraulic cylinders was performed using a single proportional-type valve with a built-in overlap-type 4-way spool valve. In the case of the velocity control, the valve opening value of a proportional-type valve was calculated by mean of a personal computer to the desired flow rate flowing into the hydraulic cylinder. For the purpose of determining the valve opening, the pressure value in the hydraulic circuit was detected using pressure sensors and a characteristic restrictor equation was employed. Thus, the control method to keep the constant flow rate, which is not affected by a load, was considered.
In the force control of hydraulic cylinders, the pressure control of a cylinder chamber was carried out when the flow rate running into the cylinder was nearly equal to zero for such cases as a fastening body and a loading one. For pressure control on-off operation to a proportional-type valve method was adopted, and the desired force of the cylinder was controlled by taking a little flow in and out of the cylinder.
In this paper, the above-mentioned control methods are proposed and the control characteristics are reported.
