DE102008034783A1 - Check valve for use during electrohydraulic hoisting gear regulation of agricultural commercial motor vehicle, has sealing arrangement arranged to valve body, where supporting body of sealing arrangement encloses sealing ring in sections - Google Patents

Abstract

The check valve (8) has a valve body (18) prestressed against a valve seat (24). The valve body closes a pressure medium flow path in a closing position and is movable into an open position against the force of a spring (22). A sealing arrangement (36) is provided with a sealing ring (38) and a supporting body (40), and is arranged to the valve body, where the supporting body encloses the sealing ring in sections. The supporting body is implemented with a circumferential edge (42) protruding into the sealing ring.

Description

The The invention relates to a check valve according to the Preamble of claim 1.

Such, for example, from the German utility model DE 297 21 109 U1 Known check valves are used to allow a pressure medium volume flow from an input port to an output port and shut off in the opposite direction. Typically, such check valves have a valve body designed with a valve body which is biased by a spring against a valve seat in a blocking position. To flow through the check valve, the valve body can be lifted against the force of the spring from the valve seat. In order to allow a leak-free shut-off, a sealing ring is arranged on the rear side of the valve cone, which is pressed by a support body and the spring in the closed position against the valve seat and thus additionally seals. When in the DE 297 21 109 U1 disclosed solution, this support body is designed as an approximately conical support disk, which rests with its outer peripheral edge on the edge region of the sealing ring.

At the practical use of such check valves showed it turns out that at a flow through the check valve with large pressure medium flow rates of the sealing ring despite the backup by the support body its position of attachment to the back of the valve body can be pulled out, making the extra seal ineffective is. In extreme cases, it may happen that this sealing ring is pulled out and washed away, so that the whole hydraulic system can be damaged.

In contrast, The invention is based on the object, a check valve to create, with the even with large pressure medium flow rates a Reliable leak-free shut-off allows is.

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

Has according to the invention the check valve biased against a valve seat Valve body associated with an additional sealing ring is. This sealing ring is about a support body fixed in position. According to the invention, this support body designed so that it at least partially the sealing ring embraces.

By This encompassing of the sealing ring can also at high Pressure fluid flows occurring flow forces do not pull the sealing body out of its set position, so this check valve is a leak-free barrier guaranteed even at high pressure medium flow rates. According to the invention Concept thus becomes of a pure non-positive Actuation of the sealing ring solved and this in addition fixed in position. By grasping is the Sealing ring thus secured both in the axial and in the radial direction.

at A preferred variant of the invention is the support body about dish or pot-shaped running and has an axially projecting peripheral edge of the sealing disc engages in sections.

One Such plate or cup-shaped support body is particularly easy to produce.

there it is preferred if the sealing ring with a Stirnflächenausnehmung is executed, in which this peripheral edge of the support body at least partially immersed.

The Sealing effect can be further improved when the support body along its face facing the sealing ring surface abuts the sealing ring.

at a particularly compact solution is used which acts on the valve body in the closing direction Spring also to the sealing ring over the support body against the back of the valve body to press.

other advantageous developments of the invention are the subject of further Dependent claims.

in the Below is a preferred embodiment of Invention explained in more detail. Show it:

1 a sectional view of an executed with a check valve according to the invention control valve and

2 a detailed view of the check valve 1 ,

1 shows a section through a control valve, as used for example in an electro-hydraulic hoist control (EHR) of an agricultural utility vehicle. About such control valves, for example, the hoist cylinder of a rear or a front lift can be controlled. The basic structure of such control valves is described in detail in the issued by the applicant data sheet RD 66 125 / 09.04, so that only the essential elements for understanding the invention elements are explained and incidentally refer to this data sheet sen, the disclosure of which is to be counted as that of the present application.

Such a control valve is as a directional valve segment (valve disc) 1 of a mobile control block. According to the sectional view in 1 has such a directional valve segment 1 a valve disc 2 , which is designed with a working port A1, a return port R, a pressure port P and control terminals, not shown. In the valve disc 2 are a 2-way pressure balance 4 , a minor module 6 with a continuously adjustable metering orifice, a check valve 8th , a sink module 10 and a secondary pressure relief valve 12 added.

The operation of the sub-module 6 and the sink module 10 takes place via a proportional magnet 14 . 16 ,

To extend a hitch cylinder connected to the working port A, the auxiliary module 6 over the proportional magnet 14 adjusted so that a pressure medium flow through the 2-way pressure compensator 4 and the minor module 6 and the opening check valve 8th flows to the consumer port A1. When closing the sink module 10 and corresponding interruption of the pressure medium volume flow is the hoist cylinder via the check valve 8th Leak-free shut off. To lower the hoist cylinder is the sink module 10 over the proportional magnet 16 controlled, so that the pressure medium from the working port A1 via the sink module 10 can flow to the return port R. The pressure in the area between the working port A and the check valve 8th via the secondary pressure relief valve 12 limited.

Regarding further details of the function of this EHR control valve will refer to the data sheet mentioned above.

2 shows an enlarged view of the check valve 8th into a valve hole of the valve disc 2 is used. Accordingly, the check valve has 8th a valve body 18 , with a cone projecting in the radial direction 20 that's about a feather 22 against a in 2 indicated valve seat 24 (see also 1 ) is biased. From the back (top in 2 ) of the cone 20 a leadership federation 26 from, which is designed with a guide bore, not shown, into which a guide pin 28 a spring plate 30 dips. This one has a backing plate 32 which is in a top view from above on the representation according to 2 not as a circular disk but with regularly distributed on the circumference cutouts 34 is executed, so that the support plate 32 can flow around in the axial direction. The pressure medium can then in the illustration according to 2 flow from below in the direction of the arrow and with the cone off 20 with flow around the support plate 32 or - depending on the design - in the radial direction to the working port A1 flow. The support plate 32 is at one in the valve bore of the valve disc 2 attached circlip 35 supported.

The feather 22 is on the backing plate 32 of the spring plate 30 supported and tensioned the cone 20 against the valve seat 24 , In the solution according to the invention, an additional sealing takes place via a sealing arrangement 36 which consists essentially of a sealing ring 38 and a support body 40 consists. In the 2 bottom annular face of the sealing ring 38 lies on the back face of the cone 20 at.

According to the detailed representation Y in 2 has the annular, the guide collar 26 encompassing support body 40 an approximately plate-shaped cross-section (seen in longitudinal section) with a sealing ring 38 towards the projecting peripheral edge 42 who is in a ground 44 passes. As shown in 2 grab the pen 22 at the back of the floor 40 at.

The sealing ring 38 has in his in 2 overhead end face a corresponding to the geometry of the peripheral edge 42 trained Stirnflächenausnehmung 46 into the peripheral edge 42 dips, leaving the sealing ring 38 and the support body 40 lie substantially flat against each other. An end face section 48 of the sealing ring 38 is then correspondingly flat on the facing end face of the soil 44 of the support body 40 at.

As 2 can still be removed, the outer diameter D of the sealing ring is larger than the valve seat diameter d executed, so that the sealing ring 38 is slightly deformed when abutting the valve seat. In the illustration according to 2 is the sealing ring 38 shown in the undeformed state. The peripheral edge of the sealing ring can also dip in the axial direction in an annular recess of the valve seat.

By the partial gripping by the support body 40 becomes the sealing ring 38 supported both in the axial direction and in the radial direction, so that it is not moved out of its desired position even with large pressure medium flow rates and correspondingly high flow forces. The subsequent closing then again a leak-free system is ensured on the valve seat.

Of course, the invention is not limited to the above-described plate-like configuration of the support body 40 limited - it is important that you tring 38 positively secured both in the axial direction and in the radial direction.

The supporting body 40 can be made, for example, as a stamped or deep-drawn part of metal, while the sealing ring 38 is made of a suitable plastic material.

The Of course, check valve can also be designed with its own check valve body be and is in principle applicable to any hydraulic components.

Disclosed is a check valve whose valve body is biased against a valve seat. The valve body is associated with an additional seal, which is essentially consists of a support body and a sealing ring. According to the invention, the support body surrounds the sealing ring. In other words, the sealing ring is positively in the radial direction Position-fixed by the support body.

1

Way valve segment

2

valve disc

4

2-way pressure compensator

6

In addition to module

8th

check valve

10

lowering module

12

Pressure relief valve

14

proportional valve

16

proportional valve

18

valve body

20

cone

22

feather

24

valve seat

26

guide collar

28

spigot

30

spring plate

32

backing pad

34

peripheral recess

35

circlip

36

sealing arrangement

38

seal

40

support body

42

circumferential edge

44

ground

46

Stirnflächenausnehmung

48

Face portion

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 29721109 U1 [0002, 0002]

Claims (6)

Check valve with one against a valve seat ( 24 ) prestressed valve body ( 18 ), which in its closed position shuts off a pressure fluid flow path and which is against the force of a spring ( 22 ) is movable in an open position, wherein the valve body ( 18 ) a sealing arrangement ( 36 ) with a sealing ring ( 38 ) and a support body ( 40 ), characterized in that the supporting body ( 40 ) the sealing ring ( 38 ) at least partially encompasses. Check valve according to claim 1, wherein the support body ( 40 ) is executed approximately plate-shaped and with a sealing ring ( 38 ) projecting peripheral edge ( 42 ) is executed, the sealing ring ( 38 ) engages in sections. Check valve according to claim 2, wherein the peripheral edge ( 42 ) in a Stirnflächenausnehmung ( 46 ) of the sealing ring ( 38 immersed). Check valve according to claim 3, wherein a bottom ( 44 ) of the supporting body ( 40 ) flat on an end face portion ( 48 ) of the sealing ring ( 38 ) is present. Check valve according to one of the preceding claims, wherein an outer diameter (d) of the valve seat ( 24 ) or the valve body ( 18 ) smaller than the outer diameter (D) of the sealing ring ( 38 ). Check valve according to claim 5, wherein the spring ( 22 ) the sealing ring ( 38 ) and the support body ( 40 ) is biased against the cone rear.