DE4326536C2 - Hydraulic installation of longwall construction in mining - Google Patents

Description

The invention relates to a hydraulic device for longwall mining in a at least one hydraulic consumer associated control valve unit with a Pressure line and a return line is connected, according to the preamble of Claim 1.

In the hydraulic devices of a strut occur due to various causes Occasional short-term pressure peaks in the return line, which even the pumps pressure can significantly exceed.

This can cause damage. To secure against this, complicated means are indicated been turned.

From the publication DE 39 16 162 A1 a shut-off valve is known, which at the junction a face supply line is arranged by a pump line and automatically the The face supply line separates from the pump line if present in the shut-off valve existing filters for the pressure fluid are added and the pressure in the face supply line accordingly drops. The shut-off valve contains an unlockable non-return valve valve that shuts off the longwall supply line in cooperation with others Components of the shut-off valve closes when the pressure in the face supply line due to clogging of the filter has dropped. An impact on pressure peaks in the return line is not available.  

The invention has for its object damage in a simple manner by pressure peaks Avoid in the return line, especially in the control valve unit.

According to the invention, this object is achieved in that on the control valve unit an opening after the pressure line between the pressure line and the return line Check valve is arranged.

This does not mean preventing and rapidly reducing the pressure peaks. It will but avoided reversing the printing direction, which is usually the cause of the damage is.  

This is particularly important for the type of slide control with the sealing rings during the switching process from one through step for the pressure medium or such a row of holes be run over. Anyhow, at a crack would reverse the direction of flow of the sealing ring destroyed.

The check valve is preferably on a base plate a component to be attached known control valve unit designed, and the valve units are each with a provided such a check valve. Individual controls can also be used in a corresponding manner Check valve are provided.

The drawings give exemplary embodiments of the invention again.

Fig. 1 is a circuit diagram showing a first valve unit,

Fig. 2 shows a circuit diagram of a second valve unit, and

Fig. 3 is a circuit diagram showing a third valve unit.

The control valve unit denoted by 1 consists in all three cases in a manner known per se from a plate 2 with drilled connecting lines and connections on its surface as well as four slide valves 3 attached to the plate 2 and a blind part 4 .

The plate 2 is connected to a pressure line P and a return line R via further attached components with a filter 5 and a check valve 6 as a backup in the event of incorrect connection. The consumer connections are shown at 7 .

According to Fig. 1, a separate non-return valve is arranged in the vicinity of the control valve unit 1 between the pressure line P and return line R 8.

According to FIG. 2, a check valve 9 is in a construction part 10 which is inserted between the components of the filter 5 and the check valve 6 and the plate 2 and comprises a portion of the pressure line P and return line R.

According to FIG. 3, a check valve 11 is exhibiting construction part attached on the other side of the plate 12 2 and the pressure line P and the return pipe R are guided into the component 12.

The check valves 8 , 9 and 11 are each arranged so that they open after the pressure line P.

The pressure in the return line is higher than in the pressure line, there is thus a compensation. About risk of damage it also reduces energy loss.

Reference list

1

Valve unit

2nd

plate

3rd

Gate valves

4th

Blind part

5

filter

6

check valve

7

Consumer connections

8th

check valve

9

check valve

10th

Component

11

check valve

12th

Component

Claims (5)

1. Hydraulic device of the longwall construction in mining with at least one hydraulic consumer assigned control valve unit ( 1 ) which is connected to a pressure line (P) and a return line (R), characterized in that on the control valve unit ( 1 ) between the pressure line (P ) and the return line (R) a check valve ( 8 ; 9 ; 11 ) opening after the pressure line is arranged. 2. Device according to claim 1, characterized, that the check valve is arranged in a unit with the control valve unit is. 3. Device according to claim 1 or 2, characterized in that the check valve is arranged on a slide control valve unit ( 1 ) in which the sealing rings are each between different positions of a gap through which the pressure medium flows or a row of holes through which the pressure medium flows. 4. Device according to one of claims 1 to 3, characterized in that the check valve ( 9 ; 11 ) as a on a base plate ( 2 ) one or more Ven tile ( 3 ) comprising control valve unit ( 1 ) to be attached component ( 10; 12 ) is designed. 5. Device according to one of claims 1 to 4, characterized in that all control valve units ( 1 ) of a strut are each provided with a check valve arranged in the manner mentioned ( 8 ; 9 ; 11 ).