VALVE DEVICE.

摘要

The valve device (1;50;60,61;90;100) has at least one flow rate control valve (21,22;63,76;101) installed in a valve body block (20;62,82). The flow rate control valves are joined to the interior of pilot pipes (6-9) which connect a pilot valve (2). The pilot pressure oil of a predetermined pressure is set by a relief valve (19), and is fed to a pilot type direction change-over valve (3), which is adapted to be driven in a accordance with the operation of the pilot valve. This allows a free flow of the pressure oil from the pilot valve to the direction change-over valve, and restricting a flow of the pressure oil from the direction change-over valve to the pilot valve. In the valve body block (20;62,82), a first passage (31;52;68,81) is connected to a return pipe (14;71,72,86) and extend to the relief valve.