WO2017198322A1

WO2017198322A1 - Relay valve

Info

Publication number: WO2017198322A1
Application number: PCT/EP2017/000333
Authority: WO
Inventors: Michael Kaufmann; Karsten Wilhelm LÜCHAU; Armin Sieker; Arne Stephan; Olaf Wichmann
Original assignee: Wabco Gmbh
Priority date: 2016-05-14
Filing date: 2017-03-14
Publication date: 2017-11-23
Also published as: DE102016006009A1

Abstract

The invention relates to a relay valve (10) comprising a piston (12) which is guided coaxially on a hollow cylindrical guide section (14) of a piston guide (16), wherein a piston chamber (17) is formed radially between the piston (12) and the guide section (14). By supplying compressed air to the piston chamber (17), the piston (12) can be moved axially on the guide section (14). A second section (18) of the piston guide (16) is received in a valve guide (20) arranged in a housing (24), and a first radially inner annular space (30) and a second radially outer annular space (32) are formed radially between the housing (24) and the second section (18) of the piston guide (16). A valve element (38) of a valve (40), said valve element being axially pressed against a valve seat (44) by a pressure spring (36), can be actuated by means of the piston (12), and the second annular space (32) can be connected to a pressure chamber (48) by means of the valve (40). In the relay valve, the valve seat (44) can be locked with the housing (24) by means of a bayonet connection (50) in order to secure the position of the valve seat. In this manner, a particularly rational assembly and disassembly of the valve seat (44) is made possible among others.

Description

relay valve

description

The invention relates to a relay valve with a piston which is guided coaxially on a hollow cylindrical guide portion of a piston guide, in which a piston chamber is formed radially between the piston and the guide portion, in which by supplying compressed air into the piston chamber of the piston on the guide portion axially displaceable is, in which a second portion of the piston guide is received in a housing disposed in a valve guide, in which radially between the housing and the second portion of the piston guide, a first, radially inner annular space and a second, radially outer annular space are formed, in which the piston is pressed by a compression spring axially against a valve seat pressed valve body of a valve, and in which by means of the valve, the second annulus is connectable to a pressure chamber.

From the prior art compressed air operated relay valves for motor vehicles in various embodiments are known. These relay valves are usually mounted in these existing valve seats with fasteners, such as circlips or screws within the housing of the relay valve. Disadvantages of this include, inter alia, a complex assembly of the relay valve, the need for additional fasteners and the latent risk of entry of contaminants in the valve housing during assembly.

The invention is therefore based on the object to introduce a relay valve that can be mounted and dismounted easily and without separate fasteners.

This object is achieved by a relay valve having the features of claim 1. Advantageous developments are mentioned in the dependent claims. Accordingly, the invention is based on a relay valve with a piston which is guided coaxially on a hollow cylindrical guide portion of a piston guide, in which a piston chamber is formed radially between the piston and the guide portion, wherein by supplying compressed air into the piston chamber of the piston on the Guide portion is axially displaceable, in which a second portion of the piston guide is accommodated in a housing arranged in a valve guide in which radially between the housing and the second portion of the piston guide, a first, radially inner annular space and a second, radially outer annular space are formed in which by means of the piston a by a compression spring axially against a valve seat pressed valve body of a valve is actuated, and in which by means of the valve, the second annulus is connectable to a pressure chamber. To achieve the object, it is provided that the valve seat can be locked to the housing by means of a bayonet connection.

The bayonet connection means between the valve seat and the housing of the relay valve, a simple assembly and disassembly of the relay valve is given without the risk of entry of foreign particles in the housing. In addition, no additional separate fastening means for fastening and securing the position of the valve seat in the housing of the relay valve are necessary. In addition, the bayonet lock of the valve seat at the same time ensures a secure position of the valve guide in the housing.

According to an advantageous embodiment of the relay valve is provided that the valve body of the valve is annular and has an approximately U-shaped cross-sectional geometry. As a result, the valve body has a high torsional rigidity and, associated with this, a reliable sealing effect of the valve body on a valve seat is provided.

According to a further advantageous embodiment, provision is made for the valve seat to have at least three bayonet lugs arranged radially outward relative to one another with respect to the circumference and arranged with at least three bayonet lugs open radially inwardly and circumferentially spaced from one another. recordings of the housing to create the bayonet connection interact. Preferably, the distances between the bayonet plates or between the bayonet receptacles are identical. As a result, a mechanically reliable attachment of the valve seat in the valve guide can be realized, which is relatively quickly feasible and solvable.

An advantageous embodiment provides that the bayonet connection has a latching device, wherein the latching device has a latching hook and a recess. Here, the latching hook is formed latched in the recess.

A further development of the last-mentioned co-production provides that at least one catch hook is formed on an end face of the valve guide facing the valve seat, which can be latched with an associated recess in a valve guide side end face of the valve seat. This is a reliable

Anti-rotation of the valve seat in relation to the valve guide given. There may be two or more recesses and snap hooks are provided. The latching hook is resilient.

It can further be provided that the at least one latching hook has a latching projection with a run-on slope and a latching edge lying opposite thereto, the latching edge being aligned parallel to a longitudinal center axis of the relay valve and the run-up slope being inclined to this longitudinal center axis.

In this way, if necessary, a simple disassembly of the latched with the valve guide valve seat is possible, as explained in detail in the following description of an embodiment.

According to a further technically advantageous embodiment can be provided that the piston has an axially inwardly directed hollow cylindrical extension with a wedge-shaped tapered, axially end-side actuating portion for the axial actuation of the valve body. This is a reliable operation of the Valve body at a circumferentially even distribution of the same

Actuating force given to this.

According to another embodiment of the relay valve can be provided that the valve guide with two O-rings and the valve seat with an O-ring against a radially close to the valve body bore of the housing are sealed.

As a result, a reliable seal is stationary in the housing

recorded valve guide relative to the housing.

Another refinement of the relay valve provides that the piston is sealed by means of a sealing ring, in particular an air ring, with respect to a bore of the housing which is radially remote from the valve body. This is a reliable

Ensures sealing effect at the same time smooth axial displacement of the piston.

According to a further embodiment it can be provided that the radially inwardly formed first annular space of the valve guide is at least partially coaxially surrounded by the second annular space of the valve guide, that the first annular space and the second annular space are radially separated from each other by an intermediate ring wall, and that the two annular spaces are open in the axial outward direction towards the piston. As a result, a structurally simple construction of the relay valve is given.

According to another embodiment it can be provided that in the first, radially inner annular space, the compression spring is accommodated, that a radially inner axial leg of the valve body rests against a radially inside the compression spring (36) arranged annular wall of the valve guide, and that a radially outer axial Leg of the valve body surrounds the intermediate ring wall of the valve guide radially outboard. As a result, a reliable guide is given both necessary for the automatic closing of the valve compression spring and the valve body, which serves as a shut-off. Finally, it can be provided that an outer ring wall of the valve guide rests at least partially on the valve body radially adjacent bore of the housing. As a result, a reliable seat of the valve guide is given in the housing.

For a better understanding of the invention, an embodiment is shown in the accompanying drawings. In the drawing shows

1 shows a partial longitudinal section through an inventive relay valve with a valve in the closed state, and

2 is a partial perspective view of the relay valve of FIG .. 1

The illustrated in Fig. 1, operated with compressed air relay valve 10 has an approximately funnel-shaped piston 12, which is taken with its hollow cylindrical portion coaxially on a substantially hollow cylindrical guide portion 14 of a likewise approximately funnel-shaped piston guide 16. An axially adjacent to the guide portion 14 of the piston guide 16 and approximately cylindrical second portion 18 of the piston guide 16 is received in a valve guide 20 which is arranged in a radially relative to a valve body 38 bore 22 of the housing 24 of the relay valve 10.

The valve guide 20 is sealed by means of two O-rings 26, 28 against the valve body 38 radially adjacent bore 22, wherein the valve guide 20 in the region of the piston remote O-ring 28 via a non-illustrated circumferential shoulder on the valve body 38 radially near bore 22nd is axially supported. The second portion 18 of the piston guide 16 is axially inwardly, so directed away from the piston 12. It extends into the region of the two mentioned O-rings 26, 28 and is coaxially encompassed by the valve guide 20.

The valve guide 20 defines a radially inner first annular space 30, which is coaxially enclosed by a radially outer second annular space 32, wherein the two annular spaces 30, 32 are separated from each other in the radial direction by an intermediate ring wall 34. In the radially inner annular space 30 is a cylindrical compression spring 36th arranged, which is axially supported on the piston remote bottom of this annular space 30. With its other axial end, the compression spring 36 acts on a valve body 38 of a valve 40 in the axial outward direction with its spring force. As a result, the valve body 38 is pressed against a circular, bead-like sealing edge 42 of a valve seat 44 of the valve 40. The piston 12, the piston guide 16, the valve guide 20 and the valve 40 are formed rotatiönssymmetrisch to a longitudinal central axis 46 of the relay valve 10. By means of the valve 40, a pneumatic connection between the second, radially outer annular space 32 and a pressure chamber 48 can be produced or separated. This pressure chamber 48 is limited inter alia by the housing 24 and the radial outer side of the piston 12, and from this goes from an unrecognizable compressed air line, which leads, for example, to a vehicle brake.

The valve seat 44 is sealed by means of a third O-ring 52 with respect to the valve body 38 radially adjacent bore 22 of the housing 24. According to the invention, the valve seat 44 is connected by means of a bayonet connection 50 to the housing 24 of the relay valve 10.

The piston 12 is sealed by means of a sealing ring 54, in particular an Airzetrings, opposite to a valve body 38 radially distant bore 56 of the housing 24 of the relay valve 10. Between the radial portions of the piston guide 16 and the piston 12, a piston chamber 17 is formed, in which the operation of the piston 12 compressed air can be introduced. The piston 12 further has an axially inwardly directed, hollow cylindrical extension 58 with a wedge-shaped sharply tapered operating portion 60 which is lifted in the closed state of the valve 40 shown here or in the case of an unactuated piston 12 from the valve body 38.

In a hollow-cone-truncated initial section 62 of the valve guide 20 that widens in a funnel-like manner in an axially outward direction, a circular cover 64 is inserted. The valve body 38 radially remote bore 56 of the housing 24 is closed with a cover 66, to the axially inside the Abde- 64 and a peripheral edge 68 of the hollow frusto-conical starting portion 62 of the valve guide 20 connect. Through the lid 66, the interior of the housing 24 of the relay valve 10 is hermetically sealed relative to the environment 70.

The valve body 38 has an approximately annular geometry with a U-shaped cross-sectional geometry. A radially inwardly disposed first leg 74 of the valve body 38 abuts the radially outer side of an axially extending annular wall 76 of the valve guide 20, and a radially outer second leg 78 of the valve body 38 surrounds the intermediate ring wall 34 radially outward. An outer annular wall 80 of the valve guide 20 bears against the bore 22 of the housing 24 which is radially close to the valve body 38.

By the inflow of compressed air into the piston chamber 17, the piston 12 is displaced axially inwardly. In this case, the piston 12 moves on the guide portion 4 of the piston guide 16 in the direction of the valve body 38. As soon as the piston 12 meets with its actuating portion 60 on the valve body 38, the force of the compression spring 36 acts on the piston 12. In this spring force is overcome Valve body 38 lifted from the sealing edge 42 of the valve seat 44 and the open state of the valve 40 is reached. In the open state of the valve 40, which the figures do not show, the radially outer annular space 32, as merely indicated by a dotted flow path 82, is pneumatically connected to the piston-near pressure chamber 48.

FIG. 2 shows a perspective partial view of the relay valve 10 shown in FIG. 1.

The section-wise funnel-shaped piston 12 is axially slidably received in the valve body 38 radially distant bore 56 of the housing 24 and sealed by means of preferably realized with the air ring ring 54 as sealing ring. The valve body 38 radially distal bore 56 of the housing 24 is closed axially outwardly with the cover 66. The approximately hollow-cylindrical valve seat 44 is located within the bore 22, which is radially close to the valve body 38, by means of the bayonet connection 50. consolidates. For this purpose, the valve seat 44 preferably has six bayonet tabs arranged radially outwardly and circumferentially equally spaced from each other, of which three bayonet tabs 90, 92, 94 are visible here. In the case of six bayonet tabs also six complementary to the bayonet tabs 90, 92, 94 formed bayonet receptacles are provided. The bayonet receptacles are circumferentially uniformly spaced apart in the region of a shoulder 96 between the valve body 38 radially distant bore 56 and the valve body 38 radially proximal bore 22 of the housing 24 formed on the same, in Fig. 2 only two bayonet receptacles 98, 100 visible and are designated.

By rotating the valve seat 44 by about 30 ° about the longitudinal central axis 46, each bayonet tab 90, 92, 94 at least partially positively in each case an associated bayonet receptacle 98, 100 of the housing 24 can be introduced.

The bayonet tabs 90, 92, 94 and the associated bayonet receptacles 98, 00 cooperate to form the bayonet lock 50. Thus, the valve seat 44 can be easily axially inserted and then rotated about its longitudinal central axis 46 by means of a suitable tool in the direction of an arrow 102 or clockwise by about 30 ° reliably lock with the housing 24 of the relay valve 10. By the positionally secured by means of the bayonet connection 50 valve seat 44 at the same time the valve guide 20 is fixed axially reliable within the radial direction of the valve body 38 bore 22. The sealing of the valve seat 44 against the housing 24 by means of the third O-ring 52 and the sealing of the valve guide 20 by means of the visible here first O-ring 26th

In order to prevent an uncontrolled rotation of the valve ring 44, on a valve seat 44 facing end face 104 of the valve guide 20, a resilient latching hook 106 integrally formed with a latching projection 108. In this case, the latching hook 106 can deflect axially in the direction of the valve guide 20. The locking projection 108 of the latching hook 106 has a run-on slope 1 10 and one of these opposite locking edge 1 12, wherein the run-on slope 1 10 under one of the better graphic overview not designated angle inclined with respect to the longitudinal central axis 46, while the locking edge 1 12 is formed parallel to this extending.

On an end face 1 14 of the valve seat 44, which rests against the end face 104 of the valve guide 20 in abutment, preferably six, each complementary to the locking projection 108 formed recesses 1 16 are provided according to the preferred number of bayonet tabs and bayonet receptacles, of which only two Recesses 1 16 are visible. The recesses 116, which are designed to be complementary to the latching projection 108, accordingly also have a run-on bevel 118 and a latching edge 120.

The locking projection 108 of the latching hook 106 is here at least partially positively locked with the recess 116, so that the valve seat 44 is reliably secured against uncontrolled rotation. When disassembling the valve seat 44, this is further rotated in the direction of the arrow 102, whereby the run-on bevel 118 of the recess 116 can slide along the run-on bevel 110 of the latching projection 108, as a result of which the latching hook 106 springs axially in the direction of the valve guide 20. As a result, the latching projection 108 of the latching hook 106 and the recess 1 16 of the valve guide 20 are unlocked, and the valve seat 44 can be further rotated in the direction of arrow 102 until the bayonet connection 50 is completely unlocked. If all the bayonet tabs are located outside the respectively assigned bayonet receptacles, the bayonet connection 50 is completely unlocked and the valve seat 44 can be lifted off the valve guide 20 in the axial direction.

In addition, an axially in the direction of the piston 12 pointing small cam 122 is exemplarily formed on a bayonet 94, which in conjunction with a recess, not shown in an associated bayonet mount 100, inter alia, reaching the locking position of the bayonet connection 50 in a haptic for a user clearly and intuitively perceptible way signals. In addition, by the in the locked position of the bayonet fitting 50 at least partially positively received in the recess cam 122 a rotation of the valve seat 44 is given to prevent the same uncontrolled release reliably. After overcoming the holding force of the cam 122, the valve seat 44 can be further rotated in the direction of the arrow 102 so that the latching hook 108 disengages from the recess 16 in the valve seat 44 and the valve seat 44 can be rotated further in the direction of the arrow 102. After the complete unlocking of the bayonet connection 50, the disassembly of the valve seat 44 can then take place by axially lifting or pulling it out of the valve body 38 radially near bore 22 of the housing 24 of the relay valve 10.

Claims

claims

1 . Relay valve (10) having a piston (12) coaxially on a hollow cylindrical guide portion (14) of a piston guide (16) is guided, in which a piston chamber (17) is formed radially between the piston (12) and the guide portion (14) in which, by supplying compressed air into the piston chamber (17), the piston (12) is axially displaceable on the guide section (14), in which a second section (18) of the piston guide (16) is arranged in a housing (24) Valve guide (20) is received, in which radially between the housing (24) and the second portion (18) of the piston guide (16), a first, radially inner annular space (30) and a second, radially outer annular space (32) are formed, in which by means of the piston (12) by a compression spring (36) axially against a valve seat (44) depressed valve body (38) of a valve (40) is actuated, and in which by means of the valve (40) of the second annular space (32) with a pressure chamber (48) is connectable, dad urch marked,

in that the valve seat (44) can be locked to the housing (24) by means of a bayonet connection (50).

2. Relay valve according to claim 1, characterized in that the valve body (38) of the valve (40) is annular and has an approximately U-shaped cross-sectional geometry.

3. Relay valve according to claim 1 or 2, characterized in that the valve seat (44) at least three radially outwardly, circumferentially spaced from each other arranged bayonet tabs (90, 92, 94) arranged with at least three radially inwardly open and circumferentially spaced from each other Bayonet receptacles (98, 100) of the housing (24) cooperate to create the bayonet connection (50).

4. Relay valve according to one of claims 1 to 3, characterized in that the bayonet connection (50) has a latching device, wherein the latching device a latching hook (106) and a recess (1 16), and wherein the latching hook (106) in the recess (1 6) is formed latched.

5. Relay valve according to claim 4, characterized in that at one of the valve seat (44) facing end side (104) of the valve guide (20) at least one latching hook (106) is formed, which with an associated recess (1 16) in a valve guide end face (14) of the valve seat (44) can be latched.

6. Relay valve according to claim 5, characterized in that the at least one latching hook (106) has a latching projection (108) with a run-on slope (1 10) and a locking edge opposite thereto (12).

7. Relay valve according to claim 6, characterized in that the latching edge (1 12) parallel to a longitudinal central axis (46) of the relay valve (10) and the run-on slope (1 10) inclined to this longitudinal central axis (46) is aligned.

8. Relay valve according to one of claims 1 to 7, characterized in that the piston (12) has an axially inwardly directed hollow cylindrical extension (58) with a wedge-shaped, axially end-side actuating portion (60) for the axial actuation of the valve body (38).

9. Relay valve according to one of claims 1 to 8, characterized in that the valve guide (20) with two O-rings (26, 28) and the valve seat (44) with an O-ring (52) opposite to the valve body (38 ) radially close bore (22) of the housing (24) is sealed.

10. Relay valve according to one of claims 1 to 9, characterized in that the piston (12) by means of a sealing ring (54) relative to a valve body (38) radially remote bore (56) of the housing (24) is sealed.

1 relay valve according to one of claims 1 to 10, characterized in that the radially inwardly formed first annular space (30) of the valve guide (20) of the second annular space (32) of the valve guide (20) is at least partially coaxially surrounded, that the first annular space (30) and the second annular space (32) by an intermediate ring wall (34) are radially separated from each other, and that the two annular spaces (30, 32 ) in the axially outward direction towards the piston (12) are open.

12. Relay valve according to claim 1 1, characterized in that in the first, radially inner annular space (30), the compression spring (36) is accommodated, that a radially inner axial leg (74) of the valve body (38) at a radially within the compression spring (36) arranged annular wall (76) of the valve guide (20) is present, and that a radially outer axial leg (78) of the valve body (38) engages around the intermediate ring wall (34) of the valve guide (20) radially outboard. 3. Relay valve according to claim 9 or 12, characterized in that an outer ring wall (80) of the valve guide (20) at least partially against the valve body (38) radially adjacent bore (22) of the housing (24).