DE102022210459A1 - Valve block and sealing insert - Google Patents

Abstract

Disclosed are a valve block and a sealing insert with a valve block, by means of which channel sections or valve disks/plates can be sealed against each other with little equipment effort.

Description

The invention relates to a valve block according to the preamble of patent claim 1 and a sealing insert suitable therefor.

Modern hydraulic work machines, especially work machines used in the agricultural sector, must meet the highest requirements in terms of functionality and availability. In addition, increasingly demanding legal requirements must be adhered to, for example with regard to operational safety. In order to meet these requirements, valve blocks with a large number of directional valve sections and the associated control valves are often used to control hydraulic consumers. As an example, reference is made to the type R..., SB... and RM... valve platforms developed by Bosch Rexroth AG. The individual sections of such valve blocks are usually each formed in a valve disk, which lie sealingly against one another with their side or flange surfaces and in the longitudinal direction, i.e. perpendicular to the flange surfaces of channels, in particular a tank channel, a pump channel, possibly a load signaling channel and / or control channels are interspersed. In the area of the adjacent flange surfaces, sealing ring seats are formed in the mouth area of the respective channels, into which O-rings surrounding the respective channel transition are sealingly inserted.

The valve discs forming the above-mentioned directional control valve sections generally each have two working connections, to which quick couplers can be arranged for faster coupling and uncoupling of hydraulic lines, for example hydraulic hoses, so that in the case of several directional control valves, several such quick couplers are placed together. The structure of such arrangements is in the DE 10 2020 206 582 A1 described. This known concept provides for hydraulically connecting adjacent quick couplers. This is done via a connecting line that enables the connection in one assembly position and blocks the connection in a second assembly position.

Depending on the application, it may happen that the pressure medium connection between two valve discs is not desired, for example in the area of a pump channel or a tank channel. In this case, intermediate plates are mounted that block the undesired pressure medium connection, but are continuous for the other channels mentioned. The assembly takes place in the same way as for the valve discs described above that form the directional valve sections, with O-rings again being provided on both sides of the flange surfaces of the intermediate plate.

A disadvantage of such a solution is that the intermediate plate increases the length of the valve block, which contradicts the requirements for a compact hydraulic structure. Another disadvantage is that the effort involved in sealing and also the assembly effort involved in producing the valve block are considerable.

In contrast, the object of the invention is to create a simply constructed valve block that can be flexibly adapted to different requirements.

This object is achieved by a valve block with the features of patent claim 1 and by a sealing insert suitable for such a valve block.

Advantageous developments of the invention are the subject of the subclaims.

The valve block according to the invention is composed of several disks/plates that are arranged next to one another along a longitudinal axis of the valve block. Each of the disks/plates - also referred to below as valve disks - has at least one flange surface with which it lies sealingly against a flange surface of an adjacent valve disk. The valve block has several channels, for example a tank channel, a pressure channel (pump channel) and possibly an LS channel and control channels that extend through the valve disks of the valve block, with sealing points for the channels that pass through this area being formed in adjacent flange surfaces. According to the invention, a sealing insert is inserted into at least one of the sealing points to interrupt the fluid connection, which sealing insert closes the relevant channel in a valve disk with respect to the associated channel in the adjacent valve disk.

By using such a sealing insert, it is no longer necessary to provide an intermediate plate, so that the valve block can be made more compact than with the known solutions, while ensuring optimal sealing.

This also has the advantage that the same tie rods can be used to fix the valve disks as in a version in which the relevant channel is continuous - in conventional solutions, longer tie rods have to be used to join the valve block together due to the intermediate plate.

The sealing insert according to the invention can be installed in practically all channel sections passing through the respective separating plane between two adjacent valve disks, without the need for an intermediate plate. In addition, with conventional solutions, different intermediate plates must be provided depending on the channel to be shut off and the valve block structure. The sealing inserts according to the invention, on the other hand, can be used in different valve block types regardless of the outer contour.

All in all, the solution according to the invention is characterized by a high degree of flexibility with low device-related expenditure.

In one embodiment of the invention, the sealing insert is approximately cylindrical with a central collar, to which sealing sections are connected on both sides, which are recessed in the outer diameter and are inserted in a sealing manner into the channels of adjacent valve disks that open into a sealing point. The central collar then preferably sits in the sealing ring seat formed on the flange surfaces of the valve disks, so that no changes to the valve disks are necessary. It is particularly preferred if the ring end surfaces of the central collar are in sealing contact with the flange surfaces of the valve disks on the opening side, so that no O-ring is required in this area.

The production of the sealing insert is particularly simple if it is made of a metallic material.

The invention can be implemented particularly easily in valve blocks with several directional valve sections, each of which is designed by valve disks. Such valve disks forming directional valve sections usually have a main slide, which is guided in the valve disk transversely to the longitudinal axis of the valve block and via which the valve disk-side working connections can be connected either to the tank channel or the pressure channel (pump channel) of the respective directional valve section. The sealing insert can then be inserted sealingly in the area of the sealing point into the tank or pressure channels of the two adjacent directional control valve sections that open there.

Central connection plates are often provided for such valve blocks, to which additional valve discs or plates with different functions are connected on both sides. These central connection plates have pressure, tank and possibly LS channels and/or control channels that are in fluid communication with the corresponding channels on both sides of the central connection plate. Accordingly, the sealing insert is then inserted in the area of the sealing point in the channel of the directional valve section or other plate/valve disc and the central connection plate that opens there.

A corresponding positioning can also take place in an LS channel, at one end section of which there is a highest load pressure, which is equal to the highest of the pressures at the working ports of the valve block, with the sealing insert then in the area of the sealing point in the LS channel sections of adjacent valve disks/ Plates are inserted.

The sealing insert according to the invention has - as explained above - a central collar, which is adjoined on both sides by sealing sections set back in the outer diameter, the diameter of which corresponds to the diameter that the channel sections to be sealed in the area of the sealing point have. In principle, it is possible for the sealing sections to have different diameters.

• 1a, 1b Prinzipdarstellungen eines herkömmlichen bzw. eines erfindungsgemäßen Ventilblocks;
• 2a, 2b schematisierte Schnittdarstellungen weiterer Ausführungsbeispiele eines herkömmlichen Ventilblocks bzw. eines erfindungsgemäßen Ventilblocks;
• 3 eine Einzeldarstellung eines erfindungsgemäßen Ventileinsatzes und
• 4 bis 7 konkrete Ausführungsbeispiele von Ventilblöcken mit einem erfindungsgemäßen Dichteinsatz.

Preferred embodiments of the invention are explained in more detail below with reference to schematic drawings. They show:

• 1a , 1b Schematic representations of a conventional valve block or a valve block according to the invention;
• 2a , 2 B Schematized sectional views of further embodiments of a conventional valve block or a valve block according to the invention;
• 3 a detailed view of a valve insert according to the invention and
• 4 to 7 concrete embodiments of valve blocks with a sealing insert according to the invention.

1a shows a schematic diagram of a conventional valve block 1, which is designed, for example, with three directional valve disks 2, 4, 6, each forming a directional valve section, each having two working ports A, B and which are penetrated in the longitudinal direction of the valve block 1 by pressure medium channels, of which, for example, 1a a tank channel 8 and a pump channel 10 are shown. Of course, other channels, for example load signaling channels or control channels or the like, can also be provided.

The front end of the valve block 1 is formed by two connection plates 12, 14, the connection plate 12 being designed with a tank connection T and a pressure connection P. The latter is connected to a pump 16, while the tank connection T has a tank channel with a Tank is connected. In the 1a Connection plate 14 arranged on the right has only one pressure connection P, which is connected to another pump 18. Both pressure connections P are connected to the pump channel 10 mentioned above.

The five disks/plates of the valve block 1 are connected via tie rods (not shown), whereby adjacent flange surfaces 20, 22 are pressed against each other, so that the channel sections opening into this sealing point are sealed via the O-rings arranged between the flange surfaces 20, 22.

In the event that only the valve disc 6 is to be supplied with pressure medium via the pump 16, 1a In a conventional manner, an intermediate plate 24 can be inserted between the valve disks 4, 6, which blocks the pressure medium connection between the channel sections 10a, 10b, but continues to connect the tank channel 8 to all three directional valve disks 2, 4, 6.

In the representation according to 1a you can clearly see that the length of the valve block (horizontal in 1 a) is increased by inserting the intermediate plate 24, whereby longer tie rods are required for fixing. The intermediate plate 24 must also be designed with the sealing ring seats for the O-rings. In addition, the channel sections passing through the intermediate plate 24 must be designed individually according to the specification depending on the position of the channel to be blocked off.

These disadvantages are overcome by the invention described in 1b The concept presented has been overcome.

The basic structure of the valve block 1 corresponds to that in 1a . This valve block 1 is also designed with directional valve disks 2, 4, 6 forming three directional valve sections and two connection plates 12, 14 arranged on the end sections. The connection diagram with the working connections A, B, the tank connection T and the pump connections P also corresponds to that in 1a . Instead of the intermediate plate 24, which is difficult to manufacture and assemble, according to the invention, a sealing insert 28 is inserted into the sealing point 26, which is penetrated by the two channel sections 10a, 10b to be separated from one another, which preferably seals in the mouth areas of the two channel sections 10a, 10b to be closed off from one another immerses. Such a sealing insert 28 can be used in practically every sealing point 26 of the valve block 1 and has the considerable advantage that there is no extension of the valve block 1, so that it is significantly more compact in terms of external dimensions than the one in 1a The variant shown can be carried out.

This is again demonstrated by the 2a , 2 B which show a further embodiment of a valve block 1 according to the invention.

2a shows a sectional view of a conventional valve block 1 with an end plate 30, a directional valve disc 2 and a further connecting directional valve plate 32, in which both a directional valve arrangement and the connections of the valve block, for example a tank connection T, are formed. In the sectional view according to 2a the valve slide 34, 36 is visible, which is adjustable in the respective valve disc and, as explained above, can be used to connect the pump channel and the tank channel to the working connection A or B. A section of the tank channel 8 is also visible in the end plate 30. In principle, this end plate 30 can also be designed as a connection valve plate or as an end valve plate.

As stated, the flange surfaces 20, 22 are formed in the contact area of adjacent plates/valve disks, for example in the contact area of the end plate 30 on the directional valve disk 2, with a sealing ring seat 38 recessed relative to the flange surface 22 being formed in the sealing point 26 of the tank channel 8. In the exemplary embodiment shown, this sealing ring seat 38 is only formed in the flange surface 22 of the valve disk 2. In principle, however, the sealing ring seat 38 can also be formed in the other plate, for example in the end plate 30 or in both disks/plates. An O-ring 40 is inserted into this sealing ring seat 38 so that the sealing point 26 is sealed in the transition area of the tank channel 8 from the end plate 30 to the directional valve disk 2. With appropriate adjustment of the valve slide 34, 36, pressure medium can then be discharged through the valve disk 2 and the connecting directional valve plate 32 to the tank via the common tank connection T.

2 B shows a variant of this valve block 1, whereby in this embodiment, instead of the end plate 30, a connecting directional valve plate 42 is provided, on which a tank connection T` is also formed. The other structure of the directional valve disc 2 and the first-mentioned connecting directional valve plate 32 corresponds to that in the embodiment according to the 2a .

A preload valve 44 is provided in the second connecting valve plate 42, which is acted upon in the opening direction by the pressure in the tank channel 8 and in the closing direction by the force of a return spring 46 and the pressure in the tank T`. is. The pressure medium connection to this tank T` is accordingly only opened when the inlet pressure of the pressure preload valve 44 (boost valve) is greater than the tank pressure by the spring equivalent. In the event that this pressure is to be prevented from being reduced to the other tank connection T or the connecting directional valve plate 32 is subjected to this higher tank pressure, a sealing insert 28 according to the invention can be inserted into the sealing point 26 between the flange surfaces 20, 22 (for the sake of simplicity, the same reference numeral combination 20, 22 is used for all sealing surfaces), so that the tank channel section 8b remains connected to the tank T and the tank channel section 8a of the directional valve disk 2 is subjected to the higher pressure specified by the preload valve 44. As explained in more detail below, the sealing insert 28 is inserted section by section into the sealing ring seat 38. The O-ring 40 can also be accommodated in the stepped sealing ring seat 38 so that a reliable seal to the outside is achieved.

3 shows an individual representation of this sealing insert 28. In the exemplary embodiment shown, this is made of a metallic material and designed in the manner of a stepped cylinder. Accordingly, the sealing insert 28 has a central collar 48, from which two radially recessed, approximately cylindrical sealing sections 50, 51 protrude towards the end sections, the diameter D of which is adapted to the diameter of the channel sections to be sealed against one another. The width B of the collar 48 is designed so that it can be inserted into the sealing ring seat 38. Accordingly, the length L of the two sealing sections 50, 51 each dips into the adjacent channel section, with the collar 48 serving as an axial stop which limits the immersion depth.

Due to this geometry, the sealing insert 28 can be inserted flush into the respective sealing point 26, so that it is ensured that the associated flange surfaces 20, 22 continue to lie flat against one another and the other channels opening into them are sealed via the O-rings 40.

The 4 to 7 show concrete exemplary embodiments of valve blocks 1 for applications in mobile hydraulics. A large number of valves and other hydraulic components are shown in these figures, but are not described in detail, but only to the extent necessary for understanding the function and application of the sealing insert according to the invention.

The in 4 Valve block 1 shown has a connection plate 12 with a pressure connection P, a tank connection T, an LS connection and a control connection Y. In this connection plate 12, a primary pressure relief valve, an LS pressure relief valve and a pressure compensator arrangement are arranged in a manner known per se.

A reversing plate 52 is arranged adjacent to the connection plate 12, which has a directional control valve via which the pump channel 10 and the tank channel 8 can optionally be connected to LS directional control valve discs 4, 6 arranged following the valve plate 52, in each of which an LS directional control valve section is integrated with a structure known per se. A primary pressure relief valve is also provided in the reversing plate 52. The directional control valve sections of the LS directional control valve discs 4, 6 each have an LS proportional valve to which a section pressure compensator is assigned. Depending on the design, pressure valves with a combined feed function and unlockable check valves can also be provided. The lateral end of the valve block 1 is formed by a connection plate 14, on which an LS connection, a tank connection T1 and a pressure connection P1 are formed. A bypass line 54 connects the pressure port P1 with the pressure port P' of the reversing plate 52. Shuttle valves are also arranged in the individual plates/valve disks, via which the highest load pressure is tapped at the working ports A, B and reported to the LS pump 16.

As in 4 As shown, a sealing insert 28 according to the invention is inserted into the pump channel 10 at the sealing point 26 between the LS directional valve disc 4 and the LS directional valve disc 6, so that a common pressure medium supply to both LS directional valve discs 6, 8 via the pump channel 10 to the LS directional valve disc 6 and to the LS directional valve disc 8 (depending on the switching position of the directional valve of the reversing plate 52) is not possible (double flow cut off).

Accordingly, the consumers connected to the directional valve discs 2, 4 are supplied individually depending on the switching position of the directional control valve of the reversing plate 52. With this concept, the consumers arranged on the LS directional valve discs 4, 6 can be supplied with the maximum system pressure p _max independently of one another .

5 shows a valve block 1 with a central connection plate 55, one on the right (view from 5 ) attached to it is a priority valve disk 56, an LS directional control valve disk 6 and an end plate 30. The central connection plate 55 has, as shown in 5 a control port X, an LS port and a pressure port P. Another LS directional valve disk 4 is shown position according to 5 attached to the left flange surface of the central connection plate 55. In the 5 The left end face of the valve block 1 is formed by a connection plate 12, on which a tank connection T, an LS connection and a pressure connection P1 are provided.

The priority valve disc 56 has an LS connection and a pressure connection D, which is connected to the pressure connection P1 of the connection plate 12 via a pressure line 60. Depending on the switching of the priority valve of the priority valve disk 56, the LS directional control valve disk 4 can then be supplied with priority or both LS directional valve disks 4, 6 can be supplied with pressure medium together. To make this possible, valve block 1 is as follows 5 In the sealing area between the central connection plate 55 and the LS directional valve disk 4, sealing inserts 28 according to the invention are inserted into the pump channel 10 and into LS channel sections 58a, 58b, so that the pressure medium supply to the LS directional control valve disk 4 takes place with priority and the corresponding load pressure to the LS -Pump 16 is reported.

In the spring-loaded basic position of the priority valve, the LS directional control valve disc 4 and the consumers connected to it are supplied with pressure medium as priority consumers. When switching the priority valve, both LS directional control valve discs 4, 6 and the consumers connected to them are supplied with pressure medium.

6 shows a variant of the valve block 1 according to 4 , wherein the shuttle valve plate 52 is designed without a maximum pressure limiting function and the maximum pressure in the directional control valve section of the LS directional control valve disk 4 is limited to a lower value than in the other LS directional control valve disk 6. In addition, the right (view according to 7 ) Connection plate 14 only has a pressure connection P and a tank connection T. In the pressure channel 10, a sealing insert 28 is provided at the sealing point between the LS directional valve disk 4 and the LS directional valve disk 6, so that the pressure medium supply to the directional valve disk 6 - as in the exemplary embodiment 4 - via the bypass line 54. The LS pressure limitation in this section is effected via a pressure relief valve 62, which limits the LS pressure in this section to a lower value than in the other LS directional valve disk 6. Accordingly, the maximum pressure p _max in the LS directional valve section 4 is limited to a lower value (e.g. 280 bar) than in the LS directional valve section 6 (e.g. 400 bar).

The in 7 Valve block 1 shown has a connection plate 12, which has approximately the same structure as the connection plates 12 of the exemplary embodiments according to 4 and 6 has. Two LS directional control valve discs 4, 6 are attached to the connection plate 12, with the in 7 The valve block 1 is terminated on the right by a connection plate 14, on which a tank connection T1 is formed. As in the previously described exemplary embodiments, the tank channel 8 passes through the valve block 1 in the longitudinal direction, with this opening on the one hand into the tank connection T of the connection plate 12. In the sealing area between the two LS directional control valve disks 4, 6, the connection of the tank channel 8 to a tank channel section 8b is blocked by a sealing insert 28 according to the invention, so that this tank channel section 8b is connected to another tank T' via the right connection plate 14. Similar to the exemplary embodiment according to 2 B In this tank channel section 8b, which extends through the connection plate 14, a preload valve 44 designed as a pressure relief valve is provided, via which the pressure in the tank channel section 8b can be set to a higher level than in the tank channel 8 (tank boost).

As mentioned, the embodiments according to the 4 to 7 merely to illustrate the possibilities of using the sealing insert 28 according to the invention in valve blocks to realize certain circuit variants without significant modification.

Disclosed are a valve block and a sealing insert for a valve block, by means of which channel sections or valve disks/plates can be sealed against one another with little technical effort.

List of reference symbols:

1

Valve block

2

Directional valve disc

4

Directional valve disc

6

Directional valve disc

8th

Tank channel

10

Pump channel

12

Connection plate

14

Connection plate

16

pump

18

additional pump

20

flange surface

22

Flange surface

24

intermediate plate

26

Sealing point

28

Sealing insert

30

End plate

32

Connection directional valve plate

34

valve slide

36

valve slide

38

sealing ring seat

40

O-ring

42

Connection valve plate

44

Bias valve

46

Return spring

48

Federation

50

sealing section

51

sealing section

52

Reversing plate

55

Bypass line

55

central connection plate

56

Priority valve disc

58

LS channel section

60

pressure line

62

Pressure relief valve

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102020206582 A1 [0003]

Claims (9)

Valve block with a plurality of disks which are arranged next to one another along a longitudinal axis, each disk having at least one flange surface (20, 22) with which it rests sealingly against a flange surface of an adjacent disk, the valve block (1) having a plurality of channels, preferably a tank channel (8), a pressure channel (10) and optionally an LS channel (58) or control channels, which extend at least partially through the disks of the valve block (1), sealing points (26) for the channels passing through this area being formed in adjacent flange surfaces (20, 22), characterized in that a sealing insert (28) is inserted into at least one sealing point (26), which sealingly closes the relevant channel in a disk with respect to the associated channel in the adjacent disk. Valve block after Patent claim 1 , wherein the sealing insert (28) is cylindrical with a central collar (48), to which sealing sections (50, 51) set back in the outer diameter are connected on both sides, which are sealingly inserted into the channels of adjacent disks which open into a sealing point (26). Valve block after Patent claim 2 , wherein the annular end faces of the collar (48) are in sealing contact with the flange surface sections of the discs on the mouth side. Valve block after Patent claim 3 , wherein the ring end faces are immersed in sealing ring seats (38) of the adjacent discs. Valve block according to one of the preceding claims, wherein the sealing insert (28) consists of a metallic material. Valve block according to one of the preceding claims, wherein at least two adjacent disks are designed as directional valve disks (2, 4, 6), each of which is designed as a directional valve section with a valve slide (34, 36), via the two working ports (A, B) of the directional valve section can be connected either to the tank channel (8) or the pressure channel (10), the sealing insert (28) being sealingly inserted in the area of the sealing point (26) into the tank or pressure channels of the two directional valve sections that open there. Valve block according to one of the preceding claims, with a central connection plate (55), the pressure, tank and possibly LS channel of which are in pressure medium connection with corresponding channels of directional valve sections arranged on both sides of the central connection plate (55), wherein the sealing insert (28) is sealingly inserted in the region of the sealing point (26) into the channel of the directional valve section and the central connection plate (55) opening there. Valve block according to one of the preceding claims, with an LS channel (58), at one end section of which there is a highest load pressure which is equal to the highest of the pressures at the working ports (A, B), the sealing insert (28) being in the area of Sealing point (26) is inserted into the LS channel sections of adjacent directional control valve disks (2, 4, 6). Sealing insert, which is designed to be inserted into a valve block (1) according to the preceding patent claims, the sealing insert (28) being approximately cylindrical and having a central collar (48) on which sealing sections (50, set back in the outer diameter) are located on both sides. 51), whose diameter (D) corresponds to that of the channels of the valve block (1) to be sealed.

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