| 摘要 |
The invention relates to Hydraulic valve device comprising a first engine port (L) and a second engine port (N) to a double acting hydraulic motor (D ), in particular a double acting hydraulic cylinder, a tank (T), and a pump (I), a hand valve (H), which is arranged such that it connects the engine po rts (L, N) to the tank (T) and the pump (I), and which hand valve (H) has tw o open positions, wherein the pump (I) in the first open position via a line (F) is connected to the first engine port (L) and the tank (T) via a line ( G) is connected to the second engine port (N), and wherein the pump (I) in t he second open position via the line (G) is connected to the second engine p ort (N) and the tank (T) via the line (F) is connected to the first engine p ort (L), and a first nonreturn valve (IA, 8), which is arranged between the pump (I) and the second engine port (N) and opens towards the second engine port (N). Further, a piston (2), which by means of the load pressure in the first engine port (L) via a line (E) governs the first nonreturn valve (IA, 8), such that it is kept closed as long as the pump pressure does not exceed said load pres¬ sure, and a second nonreturn valve (3), which is arranged s uch that it, as long as the hand valve (H) is in its first open position, co nnects the first engine port (L) to the secondengine port (N) and opens in d irection towards the second engine port (N). |
