DE102009004322A1 - Switching valve for controlling pressurizing agent connection of two valve connections, has main stage formed as seat valve, where seat valve has controlling pressure area - Google Patents

Abstract

The switching valve has a main stage (1) formed as a seat valve. The seat valve has a controlling pressure area (12). The controlling pressure area is increased with discharge line of a pre-controlling stage connecting a tank (T). A pre-controlling stage has an electromagnetically operated seat valve.

Description

The The invention relates to a highly dynamic switching valve according to the Preamble of claim 1.

at highly dynamic switching valves will respond quickly a possible delay-free movement of a Aspired valve body. It is advantageous if the valve is constructed so that the valve body in addition for fast movement even after a short adjustment the pressure fluid connection (s) changed accordingly (z. B. opens or closes).

The publication DE 38 02 648 A1 discloses a directly controlled switching valve, which is designed as a seat valve. Its valve body is electromagnetically adjusted and causes an opening or closing of a pressure fluid connection already after a short adjustment of the valve body.

adversely At such directly controlled switching valves is their constructive Limitation to low volume flows.

For higher volume flows are pilot operated valves known in which for the feedforward control additional Control pressure lines and control pressure chambers are provided. Since, in the case of a circuit, a control pressure medium takes some time to flow through a control pressure line and to a control pressure chamber To relieve or burden, pilot valves are slower as directly controlled valves.

the opposite the invention is the object of a Highly dynamic switching valve for higher volume flows to accomplish.

These Task is solved by a switching valve according to claim 1.

Further advantageous embodiments of the invention are in the dependent Claims described.

The Switching valve according to the invention serves to control the pressure medium connection of two valve connections and has a trained as a seat valve main stage, the control pressure chamber has, that of a closing direction effective control surface a valve body is limited. In this case, a discharge line, which connects the control pressure chamber with a tank, from a pilot stage be turned on. In the control pressure chamber is a filling insert arranged, through which the volume of the control pressure space and thus reduces the hydraulic capacity of the pilot system is. This leads to an acceleration of the pressure build-up or pressure reduction in the control pressure chamber. In addition, the inventive Switching valve because of the main valve designed as a seat valve the Pressure medium connection between the two valve connections quickly opens or closes. This is the result Response speed or the dynamics of the switching valve maximizes, it is because of its execution as a pilot-controlled Switching valve for relatively high flow rates suitable.

there It is particularly preferred if the pilot stage an electromagnetic actuated seat valve has. This is also the response speed the pilot stage is maximized.

at a particularly preferred embodiment of the invention Switching valve limits a wall portion of the pilot stage the Control pressure chamber of the main stage, with an input of the pilot stage is arranged on this wall portion and thus in the control pressure chamber empties. By minimizing the cable length between control pressure chamber and pilot stage is the hydraulic capacity the pilot control system further reduces what the pressure build-up and Pressure reduction speed optimized in the control pressure chamber.

ever according to design, it may be for the sake of optimal filling the control pressure chamber be advantageous when the filling insert from several rotationally symmetrical packing consists.

there Each filler can by direct fit directly or indirectly via another filler be attached to the wall portion of the pilot stage.

at a particularly preferred embodiment of the invention Switching valve, a compression spring is arranged in the control pressure chamber, which is supported on the wall portion of the pilot stage and the valve body is acted upon in the closing direction.

at A particularly preferred embodiment is a longer filler at least in sections arranged inside the compression spring, while a shorter one Packing embraces an end portion of the compression spring. Both fillers have the shape of a hollow cylinder on and have each end-side abutment sections, on the wall section abut the pre-control stage.

at An embodiment of the shorter packing has at its front side opposite the contact section a stop ring surface for the valve body. This is the opening movement of the valve body limited.

In this case, the contact section of the extend shorter packing between the end portion of the compression spring and the wall portion of the pilot stage, so that the compression spring is supported indirectly on the contact portion of the shorter packing on the wall portion.

at A particularly preferred development is a pressure medium connection from an effective in the opening direction end face of the valve body to the control pressure chamber of the main stage intended.

Out Reasons for the fastest possible response the switching valve according to the invention is the pressure medium connection with minimum length preferably in the valve body arranged. The pressure medium connection forms a nozzle out, or it has a nozzle.

The Switching valve according to the invention is also suitable as a pilot operated pressure relief valve to limit a system pressure, the effective in the opening direction end face applied.

at an embodiment closes a valve body the pilot stage in a spring-biased home position the Relief line and connects in a switching position the control pressure chamber the main stage with the tank via the discharge line.

in the The following will be with reference to the figures, various embodiments the invention in detail. described. Show it:

1 a circuit diagram of an embodiment of a pilot-operated switching valve according to the invention; and

2 an embodiment of a pilot-operated switching valve according to the invention similar to that 1 with a trained as a seat valve pilot stage in the lateral section.

The pilot-operated switching valve according to the invention essentially has a main stage 1 and a pilot stage 2 , The main stage 1 is here as a seat valve with a seat piston 4 formed, wherein the seat piston 4 in the 1 and 2 closes a fluid connection from an input port P to an output port A. In this case, the pressure at the input port P acts on an opening direction of the seat piston 4 effective face 6 , while the pressure at the output port A is also in the opening direction of the seat piston 4 effective cone surface 7 of the seat piston 4 ,

The seat piston 4 is in a valve hole 8a a valve bush 8th slidably guided, with a (in 2 ) arranged below the front edge of the seat piston 4 sealing against a valve seat 8b the valve socket 8th is applied.

The output port A consists of one on the valve sleeve 8th arranged radial boring star, of which in 2 two holes are shown.

On one (in 2 ) upper end portion of the valve sleeve 8th is a pressure chamber housing 10 mounted (eg screwed on), wherein a stop ring surface 8c the valve socket 8th their position to the pressure chamber housing 10 Are defined.

Inside the pressure chamber housing 10 are next to the upper end of the valve sleeve 8th a control pressure chamber 12 , a compression spring 14 and two fillers 16 . 18 taken substantially rotationally symmetrical to each other.

At his (in 2 ) upper side is the control pressure chamber 12 through one on the pressure chamber housing 10 adjoining wall section 22 a pilot control housing 20 limited. The pilot control housing 20 is built approximately cuboid.

At the wall section 22 of the pilot housing 20 is an end face of an approximately hollow cylindrical shorter packing 16 with its fixation via a radial extension 16a takes place, the pressure chamber housing 10 engages behind. In a basically comparable way lies in the interior of the shorter packing 16 a longer filler 18 frontally on the wall section 22 at, with its fixation by a radial extension 18a takes place, which has a radial projection 16b of the shorter packing 16 engages behind. The two are on the wall section 22 adjacent end faces of the packing 16 . 18 flush with each other.

The compression spring 14 is in sections between the two packing 16 . 18 arranged and supported (in 2 ) at the top of the radial projection 16b of the housing-fixed shorter packing 16 while they are in (in 2 ) down into a recess 24 of the seat piston 4 dips and this applied in the closing direction with spring force.

The control pressure chamber 12 is from the pressure chamber housing 10 , the valve sleeve 8, the seat piston 4 and the wall section 22 the pilot stage 2 limited. The pressure medium of the control pressure chamber acts on this 12 the seat piston 4 over a piston surface 4d , over an inner ring surface 4b and over an outer ring surface 4c in the closing direction.

Between the control pressure chamber 12 and the input terminal P and the end face, respectively 6 of the seat piston 4 is a pressure fluid connection 26 exzent in the seat piston 4 arranged. In the pressure medium connection 26 is a nozzle 28 intended.

According to 2 flows at a concentric to the main stage 1 arranged location of the wall section 22 a pilot control line 30 in the control pressure chamber 12 that the control pressure chamber 12 with one in the pilot housing 20 arranged pilot cartridge 36 connects the sections in the pilot housing 20 is screwed. The pilot cartridge 36 has inside a 2/2-way valve 36a with a seat piston, which in a biased by a spring home position a connection between the pilot control line 30 and a tank line 38 closes. By energizing an electromagnet of the directional control valve 36a its seat piston is moved into a switching position, whereby the pilot control line 30 with the tank line 38 and thus the control pressure chamber 12 is connected to the tank T. This can be done via the directional control valve 36a a pressure relief from the control pressure chamber 12 the main stage 1 be effected to the tank T.

In the in the 1 and 2 shown basic position of the seat piston 4 the main stage 1 is the seat piston 4 at the valve seat 8b and thus closes the passage from the input port P to the output port A. The closing force is on the one hand by the compression spring 14 and on the other hand generated by the pressure of the voltage applied to the input port P pressure medium, wherein the pressure of the pressure medium at the input port P via the nozzle 28 and the pressure medium connection 26 also in the control pressure room 12 prevails and on the piston surface 4d , the inner ring end face 4b and the outer ring end face 4c acts. Here is the directional control valve 35 respectively. 36a initially closed so that the pressure medium does not have the pilot stage 2 can flow to the tank T.

When the the directional valve 35 respectively. 36a is energized, it opens a pressure medium connection, so that the pressure medium of the control pressure space 12 via the pilot stage 2 to the tank T is relieved. This reduces the closing force of the seat piston 4 essentially to the spring force of the compression spring 14 , In this state, the main stage opens 1 when the on the frontal area 6 acting pressure at the input port P and on the conical surface 7 acting pressure at the output terminal A are large enough. The opening stroke (in the 1 and 2 ) is up through the stop of the inner ring surface 4b of the seat piston 4 to a stop ring surface 16c of the shorter packing 16 limited. In this case, the pressure medium from the input terminal P to the output terminal A flow.

This process requires only about two milliseconds in the switching valve according to the invention, since the to be relieved during the switching process and to be displaced pressure medium from the control pressure chamber 12 compared to comparable valves of the prior art is reduced by about 40%. This reduction is in the switching valve according to the invention by the two fillers described above 16 . 18 reached. This is the volume of the control pressure chamber 12 and thus minimizes the hydraulic capacity of the pilot control system, wherein the switching valve according to the invention is also suitable for higher flow rates.

Disclosed is a highly dynamic switching valve for controlling the pressure medium connection two valve ports, which is designed as a seat valve main stage has, where the main stage has a control pressure chamber, the one of in the closing direction effective control surface of a Valve body is limited. In this case, a discharge line, which connects the control pressure chamber with a tank, from a pilot stage be turned on. In the control pressure chamber is a filling insert arranged, through which the volume of the control pressure space and thus reduces the hydraulic capacity of the pilot system is. This leads to an acceleration of the pressure build-up or pressure reduction in the control pressure chamber. In addition, the valve body of the designed as a seat valve main stage the pressure medium connection between the two valve connections opens quickly or closes. This is the response speed or the dynamics of the switching valve according to the invention It is maximized because of its design as a pilot-operated switching valve suitable for relatively high volume flows.

1

main stage

2

pilot stage

4

seat piston

4b

inner ring surface

4c

outer ring surface

4d

piston area

6

face

7

conical surface

8th

valve sleeve

8a

valve bore

8b

valve seat

8c

Stop ring surface

10

Pressure chamber housing

12

Control pressure chamber

14

compression spring

16

shorter packing

16a

radial extension

16b

radial head Start

16c

Stop ring surface

18

longer packing

18a

radial extension

20

pilot housing

22

wall section

24

recess

26

Pressure fluid connection

28

jet

30

pilot line

35

2/2 way valve

36

pilot cartridge

36a

2/2 way valve

38

tank line

P

input port

A

output port

T

tank

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 3802648 A1 [0003]

Claims (13)

Switching valve for controlling a pressure medium connection of two valve connections (P, A) with a main valve designed as a main valve ( 1 ), which have a control pressure chamber ( 12 ), which of a closing in the effective direction control surface of a valve body ( 4 ) is limited, characterized in that a control pressure chamber ( 12 ) with a tank (T) connecting discharge line ( 30 . 38 ) from a pilot stage ( 2 ) is controllable, wherein in the control pressure space ( 12 ) a filling insert ( 16 . 18 ) is arranged. Switching valve according to claim 1, wherein the pilot control stage ( 2 ) an electromagnetically actuated seat valve ( 36a ) Has. Switching valve according to claim 1 or 2, wherein a wall section ( 22 ) of the input stage ( 2 ) with an input of the pilot stage ( 2 ) the control pressure space ( 12 ) limited. Switching valve according to one of the preceding claims, wherein the filling insert ( 16 . 18 ) of a plurality of substantially rotationally symmetrical packing ( 16 . 18 ) consists. Switching valve according to claim 4, wherein each filling body ( 16 . 18 ) by positive engagement directly or indirectly via another filler ( 16 ) on the wall section ( 22 ) is attached. Switching valve according to one of claims 3 to 5, wherein in the control pressure chamber ( 12 ) a compression spring ( 14 ) is arranged, which at the wall section ( 22 ) and the valve body ( 4 ) acted in the closing direction. Switching valve according to claim 6, wherein a longer filling body ( 18 ) in sections inside the compression spring ( 14 ), and a shorter packing ( 16 ) an end portion of the compression spring ( 14 ), wherein both fillers ( 16 . 18 ) have the shape of a hollow cylinder and each end-side radial extensions ( 16a . 18a ), which at the wall portion ( 22 ) issue. Switching valve according to claim 7, wherein the shorter packing ( 16 ) at its radial extension ( 16a ) opposite end face a stop ring surface ( 16c ) for the valve body ( 4 ) having. Switching valve according to claim 7 or 8, wherein the radial extension ( 16a ) of the shorter packing ( 16 ) between the end portion of the compression spring ( 14 ) and the wall section ( 22 ). Switching valve according to one of the preceding claims, wherein a pressure medium connection ( 26 ) between an effective in the opening direction end face ( 6 ) of the valve body ( 4 ) and the control pressure chamber ( 12 ) is provided. Switching valve according to claim 10, wherein the pressure medium connection ( 26 ) in the valve body ( 4 ) and a nozzle ( 28 ) forms or has. Switching valve according to claim 11, which is controlled by a pilot-operated Pressure relief valve is formed. Switching valve according to one of the preceding claims, wherein a valve body of the pilot stage ( 2 ) in a spring-biased basic position, the discharge line ( 30 . 38 ) closes and in a switching position the control pressure chamber ( 12 ) with the tank (T) via the relief line ( 30 . 38 ) connects.