| 摘要 |
A Hydraulic valve device includes a first engine port and a second engine port to a double acting hydraulic motor, and a pump, a hand valve, which is arranged such that it connects the engine ports to the tank and the pump, and which hand valve has two open positions, wherein the pump in the first open position via a line is connected to the first engine port and the tank via a line is connected to the second engine port, and wherein the pump in the second open position via the line is connected to the second engine port and the tank via the line is connected to the first engine port, and a first nonreturn valve, arranged between the pump and the second engine port and opens towards the second engine port. A piston which by way of the load pressure in the first engine port via a line governs the first nonreturn valve, such that it is kept closed as long as the pump pressure does not exceed the load pressure, and a second nonreturn valve arranged such that it, as long as the hand valve is in its first open position, connects the first engine port to the second engine port and opens in direction towards the second engine port. |
