| 摘要 |
<p>A hydraulic pilot valve comprises a valve body, in which are provided a plurality of reducing valve portions each having an inlet port, an outlet port and a pressure regulating valve and providing communication and cutoff between both ports by movements of the pressure regulating valve, a plurality of pistons for actuating the pressure regulating valves of the reducing valve portions in a direction of communication, an operating lever having push members for pushing the plurality of pistons, and springs for biasing the pistons upwardly of neutral positions to have the pistons abut against and held on the push members, and swings the operating lever from a neutral position to an actuating position in one direction, so that one of the pistons is pushed to place one of the reducing valve portions in a pressure oil supplying condition where the inlet port and the outlet port communicate with each other. The other of the pistons is provided with a switching valve portion which is opened when the spring pushes up the other of the pistons, and a pressure receiving chamber is provided which pushes up at least one of the other pistons except for the one of the plurality of pistons in order to retain the operating lever in the actuating position. The pressure receiving chamber is made to communicate with the inlet port or the outlet port of the one of the reducing valve portions through the switching valve portion.</p> |
