Flow control apparatus.

摘要

A flow control valve includes a cylinder (55) in which an inflow port (52), an outflow port (53) and a return port (54) are formed. A spiral choke (60) is formed between the inflow and outflow ports. A working oil introduced from the inflow port into the cylinder flows out from the outflow port through the spiral choke. An actuating valve (56) in the cylinder so as to open and close the return port in accordance with a difference in pressure between the inflow and outflow port sides of the spiral choke. When the pressure difference exceeds a predetermined value, the actuating valve opens the return port so that a part of the working oil introduced into the cylinder is returned to the inflow side of the flow control valve.