Translation of "Vorspannventil" in English

The surplus can flow back into the tank through the so-called precharge valve.

The precharge valve 46 preferably is formed of a spring-loaded nonreturn valve.

In this replenishment case, the precharge valve 46 then remains in its closed position.

The system can hence not be evacuated via the bias valve.

Filling the system with hydraulic fluid is also blocked by the bias valve.

Optionally, also the biasing valve 4 is provided downstream of the second blocking member G 2 .

The remaining excess oil quantity in the suction/return filter system is conducted to the tank via the preload valve.

In the tank line 20 a tank line attenuator 22 and a biasing valve 24 are arranged.

Precharge valve with two different cross sections in open state.

It will be clear that only one of the hydraulic circuits can be equipped with a biasing valve of the type described.

Reference numeral 22 relates to a valve which is used here as a return gas valve and a pre-charge valve.

Excess amounts travel via the back pressure valve to the tank connection and are drained towards the tank.

The remaining excess oil quantity in the suction/return filter circuit is conducted via a preload valve 70 to the tank 68 .

In order to avoid e.g. cavitation effects it may be expedient to provide a biasing valve downstream of the second blocking member.

When retracting the volume flow is directed back to the main control valve via a check valve in parallel to the sequence valve.

After the valve 15 and the flushing valve 11 are closed, valve 17 opens as is the situation which exists in FIG. 3.

In this way the pressure in the line 61 rises, so that the pressure medium now reaches the filling spaces of the cylinders 12 through the pressurizing valve 62, the lines 63, the blocks 66 and the lines 64.

In this way, pressure builds up in a line 45 so that a pretensioning valve 46 opens and the longitudinal cylinder 47 starts a longitudinal feed.

Main lines 21, 22, 23 and 24 are connected to a circuit with one fill line 29 via branches having check valves 17, 18, 19 and 20, with the circuit being fed by a priming pump 15 via priming valve 16.

Using a control line 30, the three-way valves 11, 12, 13 and 14 are connected to a circuit that is fed by a pump 9 with a priming valve 10.

The invention teaches that the hydraulic pump 5, the distributing valve block 8, the descent braking valve 15 and the pilot valve 16 are preferably located inside the reservoir 1 .

It is convenient for the respective biasing valve to comprise a moving shut off valve member, which is biased by spring force corresponding to the desired opening pressure into a closed position interrupting the fluid path and which is acted upon by the hydraulic fluid of the output working chamber opposing the spring force in the opening direction.

The outer frontal chambers (pressure chambers) 34 and 35 on the regulating drives 6 and 7 are connected with one another by axial bores 10 and 11 in the control pistons 4 ? and 5 ? and are further connected with the pressure medium outlet T via a pressure-limiting valve 36 disposed in the center.

This pressure-limiting valve 36 is realized here as an elastic sealing ring 15, which is pre-stressed from the outside in radial direction over the ends of the two control sleeve segments 23 and 33 .

A pressure valve can be present particularly within ascending pipe 10, which is not to be described in greater detail, allowing for increased pressure to be applied within the ascending pipe, for example in the range of from 0.5 to 1 bar.

Thus the biasing valve is responsible for biasing of the hydraulic medium located in the output working chamber, which medium can not be immediately displaced, when there is an increase in pressure in the input chamber.