PURPOSE: To prevent a vehicle from coasting as well as to keep cargoes from falling down, and protect a driver from feeling unpleasant to a great extent by constituting a neutral communication valve to be switched so as to be held at a communication position only when an actuating lever continuously remains at a neutral position beyond the specified period of time.
CONSTITUTION: A neutral communication valve 5 is switched over by a switch control means 20 to a communication position (a) only when an actuating lever 4 continuously remains at a neutral position N beyond the specified period of time. When the actuating lever 4 is therefore, switched over, for example from a normal rotation position F to the neutral position N, and is then switched over to a reverse rotation position R before the specified time elapses, the neutral communication valve 5 is held at an interruption position (b). As a result, main lines 11 and 12 are not mutually communicated, a hydraulic motor 2 will never thereby be rotated by inertia.
KANAI TAKASHI
SONODA MITSUO
