摘要 |
<p>An oil-hydraulic system for moving a gate, comprises a double-acting oil-hydraulic cylinder (11), which is intended to be kinematically connected to the gate to move it, and an electro-hydraulic pump (12) to feed and actuate the cylinder upon command. A switching valve (13) interconnects the cylinder (11) alternatively with the pump (12) or with a tank (14) of oil-hydraulic fluid. In rest conditions, the valve (13) connects the cylinder (11) to the tank (14), to allow free manual movement of a gate connected to the cylinder, and it is automatically controlled by the pressure variations in the system that are produced by the actuation of the pump (12) to disconnect the cylinder (11) from the tank (14) and connect it to the pump (12).</p> |