DE102007019222B3 - Filter systemfor use in underground workings has a cartridge-type hydraulically operated directional control valve for switching the filter from filtering operation to back-flushing operation - Google Patents

Abstract

The filter system for cleaning a medium with double filter has a cartridge-type hydraulically operated 3/2 directional control valve (13) for switching the filter from filtering operation to back-flushing operation. A common valve and filter housing has pump and filter ports (5,22), and a back-flushing outlet (7) which consists of radial bores (23) with a diameter which is larger than radial bores (18) leading into the inlet chamber (19). A pilot pressure port (26) for the filtering function and a pilot pressure port (29) for back-flushing function and pressure relief are also provided.

Description

The The invention relates to a filter system with backwashing for cleaning a medium of the entrained Dirt particles z. B. in the longwall mining operation of an underground mining through the long supply routes and also the used oil / water mixture attack. It has proved to be advantageous, double filter with independent To use filter chambers. This z. B. the two filter chambers connected in such a way by two switching balls inserted in the head, that both filter chambers are flowed through in parallel filter operation. The rotation of a switching ball causes the input side Inlet is blocked to the subsequent filter chamber. simultaneously is for the locked filter chamber releases the backwash. The backwashing of the Both filter chambers always alternately and is without interruption of the current operation feasible. As a parameter for the reversal to backwash can z. B. the pressure difference between the inlet and outlet of the filter housing can be selected. The known filter systems have themselves in rough underground operation proven and are also equally successful in other applications in use.

As a further significant prior art, the published patent applications DE 31 00 016 A1 and DE 35 26 293 A1 called. Here, however, the disadvantage is seen in that, although two filter units are arranged parallel to each other, but in each case only one filter unit is in use. If the degree of contamination of the active filter unit is too high, it is excluded from the filtering process and the backwashing for this filter unit is initiated; only then will the parallel filter unit be used. By the DE 10 2005 054 028 A1 A prior art is known in which each filter is associated with a storage valve, a backwash valve and a control valve. In addition to the structural complexity of a mutual influence of mutually parallel filter units is not provided.

Of the Invention is now based on the object to provide filter systems, the even longer lifetimes reach with fewer components for easier assembly and disassembly. According to the invention Task by the filter system according to claim 1 and the downstream dependent claims solved.

The mainly by the invention achievable advantages are the fact that the above-described State of the art is enriched in that a 3/2-way valve as a cartridge valve is used, that is preferably switched automatically and all the important functions for filtering and backwashing are combined and thus forms a compact unit. Due to the smaller diameter At the pump inlet impurities are already intercepted and the larger diameter to the filter element and to the outlet of the backwash guarantee an effective passage of the medium. Because the piston surfaces and piston ring surfaces designed to compensate for pressure, hydraulic forces are reliably avoided.

The Invention will be explained in more detail below by exemplary embodiments, wherein emphasizes that all features and measures described may be of essential importance to the invention.

The Drawings show in:

1 a 3/2-way valve in cartridge design seen from the pilot bar side;

2 in sectional view 1 an inventive 3/2-way valve in switching function;

3 another sectional plane of the valve according to the invention 1 ;

4 a filter system in side view from the right;

5 a filter unit in front view with double filter;

6 a filter system in side view from the left;

7 an enlarged sectional view according to 6 ;

8th shows control functions of the filter system.

2 shows a cut in 1 according to cutting plane AA and 3 a cut in 1 according to vertical section BB. The functions of the 3/2-way valve are described in summary according to these three figures.

The filter system 1 (please refer 5 ) consists of two on a filter head 2 attached double filter 9 passing through two in the filter head 2 used 3/2-way valves 13 are so interconnected that during filter operation, the filters 10 . 11 to be flowed through in parallel (see 8th ).

The 3/2-way valve 13 consists of the cartridge case 14 and is composed of the interconnected upper and lower parts 15 . 16 , In the lower part 16 is the pump connection 17 above small radial bores 18 with the entry chamber 19 connected. In the example shown, the valve 13 switched to backwashing and the direct pump connection 17 closed. The approved pump connection 17 of the neighboring valve 13 pushes the filtered medium via a branch 40 (please refer 8th ) through the filter arranged in parallel in the backwash direction through the filter connection 22 over the big radial holes 21 in the filter chamber 20 and through the large radial bores 23 to the tank 41 (please refer 8th ). To be able to perform this switching operation, the pilot pressure backwash chamber 30 via radial recesses 28 pressurized and the pilot piston 32 with the piston 31 against the continuous pressure in the pilot pressure chamber 24 until retracted until the piston 31 the entry chamber 19 against the pump connection 17 closed. Thus the retraction of the piston 31 is easily possible, this is with a spherical surface 33 Mistake. The normal filtering process becomes the pilot pressure backwash chamber 30 relieving the pressure via the radial recesses 28 retracted. In support of this process is the pressure assist spring 27 used. The piston ring 35 is designed slightly smaller in outer diameter than the corresponding inner diameter of the lower part 16 the cartridge case 14 , This relief gap 36 brings when switching the piston 31 , Priority in the filtration position, the advantage with it that the flow through this annular gap is broken such that impermissibly high flow velocities in the actual sealing area of the seal 38 and the deflection pulley 39 be avoided. The deflection pulley 39 ensures that in the backwashing process dirt particles from the actual sealing surface of the seal 38 be kept away.

Through the pump inlet side smaller radial bores 18 For example, coarse dirt particles are difficult to pass through the small holes and some pre-filtering is done.

The pressure balanced design of the piston crown 34 opposite the piston ring 35 and also the pilot piston 32 compensates for the forces that occur.

The 8th represents the functioning of the filter system 1 with regard to filters and backwashing. The left-hand illustration shows the backwashing for the left-hand filter 10 becomes recognizable. It is easy to see, as well as to the 1 to 3 described that the direct high pressure supply to the left filter 10 is locked and via a branch 40 , after passing the right filter 11 the filter 10 is flushed against the actual filter direction for backwashing.

The backwashing process of the filters 10 . 11 is by electrical control of only one side of the double solenoid valve 8th (A) triggered (see 8th , Backwashing left filter).

Backwashing the right filter 11 follows from the mirror image, a description is therefore not required; also results from the function image, middle representation, the normal filter operation.

In case of a possible disassembly for the renewal of the valve or valves 13 are just a few screws on the pilot bar 3 from the filter head 2 to remove. In the description, predominantly only features relevant to the invention have been described and provided with reference numerals.

1

filter system

2

filter head

3

pilot bar

4

Valve- and filter housing

5

pump connection

6

tank connection

7

backwash

8th

Double solenoid valve

9

double filter

10

filter Left

11

filter right

12

mounting strip

13

3/2-way valve

14

cartridge case

15

top

16

lower part

17

pump connection

18

Radial bores, small diameter

19

inlet chamber

20

filter chamber

21

Radial bores, greater diameter

22

filter connection

23

Radial bores, greater diameter

24

Pilot permanent pressure chamber

25

radial bores

26

Pilot pressure port

27

Notrückstellfeder

28

radial recesses

29

Pilot pressure port

30

Pilot pressure backwash

31

piston

32

pilot piston

33

bilious surface

34

piston crown

35

piston ring

36

relief gap

37

relief wells

38

poetry

39

deflection plate

40

junction

41

tank

42

piston rod

43

pressure connection

44

tank connection

45

Rückspülanschluss

Claims (16)

Filter system for cleaning a medium with double filter in a preferably parallel arrangement, in which the two filter chambers are flowed through in parallel filter operation and are mutually reversible by means of pilot valves on backwashing, characterized in that for switching the filter ( 10 . 11 ) from filtration to backwashing the filter ( 10 . 11 ) each a hydraulically actuated 3/2-way valve ( 13 ) is assigned in cartridge design, the compact design in a common valve and filter housing ( 4 ) with pump, filter connection ( 5 . 22 ), Backwash outlet ( 7 ), wherein the backwash outlet ( 7 ) from radial bores ( 23 ) larger diameter than the radial bores ( 18 ), and a pilot pressure port ( 26 ) for the filter function and a pilot pressure connection ( 29 ) is provided for the functions backwashing and pressure relief. Filter system according to claim 1, characterized in that the cartridge case ( 14 ) is designed in two parts and from an upper part ( 15 ) and lower part ( 16 ) consists. Filter system according to claim 1 and 2, characterized in that the upper part ( 15 ) the pilot pressure connections ( 26 . 29 ) for the functions Filter, Backwash and Pressure Relief and the outlet ( 7 ) for backwashing. Filter system according to claim 1 and 2, characterized in that the lower part ( 16 ) the pump and filter connection ( 5 . 22 ) includes. Filter system according to claim 3, characterized in that the radial bores ( 23 ) of larger diameter in the direction of the lower part ( 16 ) are inclined and from the filter chamber ( 20 ) go out. Filter system according to claim 3, characterized in that in the head region of the cartridge case ( 14 ) a pilot duration pressure chamber ( 24 ) arranged in the direction of the lower part ( 16 ) inclined radial bores ( 25 ) is acted upon. Filter system according to claim 6, characterized in that in the pilot duration pressure chamber ( 24 ) an emergency return spring ( 27 ) is arranged. Filter system according to claim 3, characterized in that in the front region of the cartridge case ( 14 ) radial recesses ( 28 ) are provided via which the pilot pressure backwashing ( 30 ) is applied and the pressure relief is initiated. Filter installation according to claim 4, characterized in that the filter connection ( 22 ) is provided for both the filter function and the backwash function. Filter installation according to claim 4, characterized in that the inlet of the pump connection ( 17 ) on the cartridge case ( 14 ) in the direction of the upper part ( 15 ) inclined radial bores ( 18 ) of small diameter and into the entrance chambers ( 19 ) opens. Filter installation according to claim 9, characterized in that the filter connection ( 22 ) from radial bores ( 21 ) larger diameter than that of the radial bores ( 18 ) of the pump connection ( 17 ) and into the filter chamber ( 20 ) opens. Filter installation according to one of the preceding claims, characterized in that the piston ( 31 ) is formed in two parts and in the head area of a on the Kobenstange ( 42 ) mounted pilot pistons ( 32 ) with spherical surface ( 33 ) consists. Filter system according to claim 12, characterized in that the effective piston surfaces of the piston crown ( 34 ) and the piston ring ( 35 ) are designed to be pressure balanced. Filter system according to claim 12 and 13, characterized in that the piston ring ( 35 ) in the peripheral region with a relief gap ( 36 ) to the cartridge case ( 14 ) is equipped. Filter system according to claim 12 and 13, characterized in that in the piston ring ( 35 ) Relief bores ( 37 ) are provided. Filter system according to one of the preceding claims, characterized in that in the connecting region between the upper and lower part ( 15 . 16 ) of the seal ( 38 ) a deflection disk ( 39 ) is connected upstream.