Hydraulic actuator, defroster for vehicle, and hydraulic circuit of single dynamic hydraulic cylinder

摘要

Problem to be solved: to provide a technique for simply suppressing oil leakage to a non pressurizing chamber of a single dynamic hydraulic cylinder.The inside of the cylinder case 11 is partitioned into a pressurizing chamber 10a and a non pressurizing chamber 10B by a piston 12.A return spring 15 is disposed in the non pressurizing chamber 10B, andA hydraulic actuator provided with a single dynamic hydraulic cylinder 10 to which the piston 12 is retracted by operating oil supplied to the pressurizing chamber 10A through the supply conduitThe first check valve 25 inserted into the supply line 23 andIn the supply lineA bypass passage 24 is connected between the upstream side of the first check valve 25 and the downstream side of the first check valve 25 to bypass the first check valve 25, andThe bypass passageFor pressure chamber 10AThe first check valve 25 and the second check valve 26 opposite to the flow direction of the fluid.Diagram