WO2014086569A1

WO2014086569A1 - Valve block

Info

Publication number: WO2014086569A1
Application number: PCT/EP2013/073896
Authority: WO
Inventors: Waldemar Foth; Wolfgang Hupp; Enrico Riegel
Original assignee: Robert Bosch Gmbh
Priority date: 2012-12-03
Filing date: 2013-11-15
Publication date: 2014-06-12
Also published as: DE102012222060A1

Abstract

The invention relates to a hydraulic arrangement with a valve block which is designed such that two pressure medium sources (6, 10) can be connected. A pressure medium connection between a load (26) connected to the valve block and the first pressure medium source (6) and between the load and a pressure medium sink can be controlled via a main path valve (36) of the valve block. Advantageously, the second pressure medium source (10) can additionally be fluidically connected to the load via an auxiliary path valve (46).

Description

manifold

description

The invention is based on a valve block according to the preamble of claim 1.

From EP 791 754 B1 a valve block is known, which is intended for use in a hydraulic excavator. The valve block comprises a housing in which, for each consumer or each movement axis of the hydraulic excavator, a main slide is received linearly movable in a transverse direction. In this case, the main slide with respect to a longitudinal direction which is perpendicular to the transverse direction, arranged side by side. In the housing, a first and a separate second pump channel are provided, each extending substantially over the entire length of the housing. The first and the second pump channel are connected via an associated first and second pump port to an associated first and second pump having an adjustable displacement volume.

Each main spool forms with the housing a first and a second main panel, each connected to an associated working port. At the two working ports, which are assigned to a main spool, is one each

Consumer of the hydraulic excavator connected. Through the first and the second main panel, the amount of pressure flowing under pressure to the consumer

Hydraulic fluid controlled. In this case, the first and the second main panel are each associated with opposite directions of movement of the consumer.

Accordingly, either the first or the second main panel is opened in each case.

Some main pushers are associated with a first and a second linearly movable auxiliary slide. The first auxiliary slider defines an adjustable first auxiliary orifice, via which the first pump channel is connected in parallel with the first and the second main panel. The second auxiliary slider defines an adjustable second auxiliary orifice over which the second pumping channel is parallel with the first and second main orifices connected is. Via the first and the second auxiliary orifice, it can be determined which of the two pumps will supply the associated consumer with pressurized fluid,

especially hydraulic oil supplied. By adjusting the cross-sectional area of the first and second auxiliary orifice, it can be determined which amount of fluid is conveyed by the first or the second pump to the relevant axis. The first and the second auxiliary orifice are preferably part of a proportional valve, as is known, for example, from US Pat. No. 4,779,836 A1, so that control of the volumetric flow can take place.

A disadvantage of such a valve block is that in the case of a summation, d. h., That both auxiliary valves are open, an extremely large amount of fluid (up to the sum of Fördervoluminas the pumps or hydraulic pumps) flows through the main spool, resulting in relatively large energy losses.

In contrast, the invention has for its object to provide a valve block in which at least one consumer of two hydraulic pumps with pressure medium can be supplied with low energy losses occur.

This object is achieved by a valve block according to the features of

Claim 1.

Other advantageous developments of the invention are the subject of further

Dependent claims.

According to the invention, a valve block is provided for controlling at least one consumer. In the valve block, further, a first and second supply line is formed. A respective supply line opens into a pump connection. A hydraulic pump can be connected to a respective pump connection, whereby the valve block can be supplied with pressure medium by two hydraulic pumps. To connect the consumer, the valve block has a first and second

Work connection on. A pressure medium connection between the working ports, the first supply line and a tank line can be controlled via a main directional control valve. Via the main way valve can thus pressure medium from the supply to Consumers and flow from the consumer to the tank line, with which the consumer is supplied with pressure medium and / or controllable. To supply the consumer with additional pressure medium of the second supply line is a bypass valve

intended. This controls a pressure medium connection between the second

Supply line and the first working port for the consumer.

This solution has the advantage that the consumer directly from the second

Feeding power over the bypass valve is supplied with pressure medium. The

Pressure medium of the second supply line thus does not flow, in contrast to the prior art explained above, via the main directional control valve. Thus, when the pressure medium volume flows of the two supply lines are summed, the pressure medium of the first supply line flows via the main directional valve and the pressure medium of the second supply line via the bypass valve, which leads to low flow losses in comparison with the prior art.

It would be conceivable to additionally connect each of the working connections via a bypass valve with the second supply line. For most consumers, such as an excavator, the summation is for both working ports (and thus

For example, in two directions of movement of a hydraulic cylinder) is not necessary, which is why a bypass valve is usually sufficient.

The main directional control valve is preferably a closed center main directional control valve whose valve spool shuts off all connections of the main directional control valve from one another in its middle position or has working connections with one another

Tank connection connects. Furthermore, the main directional control valve can be designed as a proportionally adjustable 4/3-way valve whose valve slide has two working positions in addition to its middle position or blocking position. In the first

Working position here, for example, the first working port with the first supply line and the second working port with the tank line and in the second working position of the first working port with the tank line and the second

Work connection to be connected to the feed line. As a consumer, as already explained above, be a hydraulic cylinder with two separate from a piston control chambers. The control chambers are then preferably connected to the two working ports of the valve block.

The bypass valve is preferably proportional

adjustable 2/2-way valve. Its valve slide may preferably have a blocking and open position.

In order for the by-pass valve to control the fluid connection to the first working port, it is at a pressure fluid flow path between the

Main way valve and the first working port connected.

For load maintenance, both the main directional valve and the bypass valve may be associated with a check valve.

Advantageously, the main directional valve is connected via a first supply line to the first supply line and the bypass valve via a second supply line to a second supply line. Furthermore, the bypass valve may be connected via a working line to the pressure medium flow path between the main directional control valve and the first working port. In the first supply line then a first and in the second supply line or in the working line, a second check valve may be arranged for load maintenance. The check valves open in each case in a pressure medium flow direction towards the consumer.

To limit the pressure can be connected to a respective supply line, a pressure relief valve, with which then a pressure medium connection to the tank or the tank line can be opened.

Device-technically simple, the associated with the bypass valve

Check valve (second check valve) and the bypass valve be designed as an assembly. The assembly may preferably be in the form of a valve spool with integrated non-return valve or in the form of a pilot-operated seat valve. In a further embodiment of the invention, two further working ports may be formed on the valve block, which a main way valve and a

Associated with bypass valve. In this case, the second main directional valve can then control a pressure medium connection of the working connections to the second supply line and the bypass valve can control a pressure medium connection between the first supply line and the first working connection. Thus, the two main directional valves are each assigned to a different supply line. The same goes for the two

By-pass valves, which are also each assigned to a different supply line. Thus, if both consumers each require at most the pressure medium flow rate of a hydraulic pump, they can be supplied with pressure medium independently of each other.

The second main way valve is preferably according to the first

Main way valve and the second bypass valve according to the first

Secondary valve formed.

In an alternative embodiment, another consumer can be connected to a first and second working port which another main and

By-pass valve is assigned corresponding to the first main and first by-pass valve. In addition, at least in a pressure medium flow path between a respective main directional control valve and the first supply line, a prioritizing valve is provided. In this way, in addition, a pressure medium volume flow to the respective main directional control valve can be adjusted, whereby advantageously one of the consumers can be prioritized and receives more pressure medium via its prioritization valve, like the other consumer. The prioritization valve is preferably a proportionally adjustable directional control valve, in particular a 2/2-way valve. Its valve slide can have a blocking and open position.

In a further preferred embodiment, hydraulic motors can be connected to two further pairs of first and second working ports. The

Working connections of the first hydraulic motor are via a main way valve with the first supply line and the working connections for the second hydraulic motor via another main way valve with a straight travel directional control valve (ST-way valve) connectable. In turn, the main directional control valve of the second hydraulic motor can be connected either to the first or second supply line via the ST-way valve. If the main directional valve of the second hydraulic motor is in this case connected to the first supply line, then the further main directional valve of the further consumer is connected to the second supply line via the ST-way valve. Is it against that

Main way valve of the second hydraulic motor via the ST-way valve connected to the second supply line, so is the other main way valve further

Consumer connected to the first supply line.

The hydraulic motors serve as a drive for a particular excavator side of the excavator.

The ST-way valve is designed such that in its neutral position the first hydraulic machine and one of the consumers are connected via its main directional control valve to the first supply line and the second hydraulic machine and the other consumer via its main directional valve to the second supply line. Between

Main way valves of the consumers and the supply lines can here again be provided a prioritization valve. The assigned to the consumers

Nebenwegeventile serve as explained above for the summation of a

Pressure medium volume flow for the consumers. In this neutral position of the ST-way valve, there is no superimposed movement of the hydraulic motors or the

Travel drives with another consumer instead. If a superimposed movement take place, the ST-way valve is adjusted such that the consumers can be connected via their main directional valves to the second supply line and the hydraulic motors via their main directional control valves to the first supply line. With partial control of the ST-way valve, a pressure equalization between the two travel drives

be ensured so that a straight ahead of the excavator is guaranteed and an unintended cornering is excluded. A summation over the

By-pass valves are preferably avoided in the superimposed movement, that is to say the connection of both hydraulic motors to the first supply line.

In a further embodiment of the invention may be connected to a respective supply line, an open-center valve, via which a pressure medium connection between the respective supply line and a tank is controllable. The open center valve is preferably a 2/2 way valve. When controlling a main and / or by-pass valve can then be controlled by the respective associated OC valve, which leads to a jam pressure in the corresponding supply line, which is necessary for the consumer. By this arrangement can thus advantageously a classic throttle control (6/3-way valve with open in the middle position neutral circulation which is throttled upon actuation of the main directional control valve to generate the necessary load pressure) allows and thus a

Load sensitivity of the hydraulic system to be readjusted.

The hydraulic pumps connected to the pump connections are preferably demand-controlled, in particular proportionally adjustable. This results in energetic advantages since, unlike constant pumps, the maximum delivery volume flow does not have to be permanently promoted.

For pressure protection of one or both working ports of one or more

Consumers can one or both work connections one

Be associated with pressure relief valve. Of course, pressure limiting valves can also be arranged for one or both working connections of the hydraulic motors.

It is conceivable to provide a central valve block section of the valve block, at which the pump connections, the supply lines, the tank line, the OC valves, the

Pressure limiting valves for the pump connections, the ST-way valve and the main directional valve for the second hydraulic motor including the associated

Work connections are arranged.

In addition, in this central valve block section or in a further standardized valve block section which can be connected thereto, the supply lines, the

Tank line, at least one main and by-pass valve for one of the consumers with working ports, the check valves associated with the main and by-pass valve, the prioritization valve and the pressure relief valves are provided for the working ports. The center and / or the further valve block section can be completed with a closure plate.

Of course, further valve block sections can be connected to the central or to the further valve block section.

The main way valve together with the working connections for the first

The hydraulic motor is preferably in the central valve block section or in the valve block section adjacent to the central valve block section

Special drilling planned.

The further valve block sections may be provided as standardized valve disks for flanging to the central valve block section, whereby these are extremely inexpensive. The valve block sections then share at least the supply lines and the tank line.

In the following, preferred embodiments of the invention will be described

schematic drawings explained in more detail. Show it:

1 shows a hydraulic circuit diagram of the valve block according to the invention according to a first embodiment,

Figure 2 is a hydraulic circuit diagram of the valve block according to a second

embodiment,

Figure 3 is a hydraulic circuit diagram of the valve block according to a third

embodiment,

Figure 4 is a hydraulic circuit diagram of the valve block according to a fourth

embodiment,

Figure 5 is a hydraulic circuit diagram of the valve block according to a fifth

embodiment,

Figure 6 is a hydraulic circuit diagram of the valve block according to a sixth

embodiment, Figure 7 is a hydraulic circuit diagram of the valve block according to a seventh

embodiment

Figure 8 is a hydraulic circuit diagram of a central valve block section of

Valve block,

9 shows a hydraulic circuit diagram of a further valve block section of the

Valve block,

Figure 10 is a hydraulic circuit diagram of another valve block section of

Valve block,

1 1 shows a section through the further valve block section of FIG. 10.

According to FIG. 1, the valve block 1 has a first and a second pump connection P1 and P2. These are connected to a first and second supply line 2 and 4, respectively. The supply lines 2, 4 extend approximately parallel to each other through the valve block. 1 A first hydraulic pump 6 is connected to the first pump connection P1 via a first pump line 8 and to the pump connection P2 a second hydraulic pump 10 is connected via a second pump line 12. The hydraulic pumps 6 and 10 in each case convey pressure medium via their respective tank line 14 or 16 from a tank T into the first and second feed lines 2 and 4, respectively.

To limit the pressure in the first and second supply lines 2 and 4, a pressure-limiting valve 18 or 20 is connected thereto via a pressure line 22 and 24, respectively. The pressure limiting valve 18, 20 are configured in the usual manner and open from a predetermined pressure, a pressure medium connection to the tank T.

A hydraulic consumer 26 in the form of a hydraulic cylinder is connected to a first and second working port A1 and A2 of the valve block 1. The hydraulic consumer or hydraulic cylinder 26 has a piston 28 with a

Piston rod 30, wherein the piston 28 an annular space 32 of a cylinder chamber 34 of the hydraulic cylinder 26 separates. Via a main way valve 36, the spaces 32 and 34 of the hydraulic cylinder 26 with the first supply line 2 or a tank T can be connected. The main way valve 36 is designed as a proportionally adjustable 4/2-way valve or close-center directional control valve, it has a first and second Working port A1 and A2, a tank port TA and a pressure port P. The working port A1 of the main directional control valve 36 is via a working line 38 to the port A1 of the valve block 1 and thus with the cylinder chamber 34th

connected. The port A2 of the main way valve 36 is via another

Working line 40 with the connection A2 of the valve block 1 and thus with the

Annular space 32 of the hydraulic cylinder 26 in pressure medium connection. The tank connection TA is connected to the tank T and the pressure connection P via a first

Supply line 42 connected to the first supply line 2. In a middle position 0 of a valve spool of the main travel valve 36, the ports A1, A2, TA and P are separated from each other. In first working positions a of the valve spool, the cylinder chamber 34 is then connected to the tank and the first supply line 2 to the annular space 32. In second working positions b of the valve spool, however, is the

Annulus 32 with the tank and the first supply line 2 with the cylinder chamber 34 in fluid communication. Thus, the spaces 32 and 34 of the hydraulic cylinder 26 can be alternately supplied with pressure medium. An actuation of the valve spool of the main directional valve 36, for example, hydraulically via control lines 44 or if necessary in other ways, for example, pneumatically or electromagnetically.

To the hydraulic cylinder 26, in particular the cylinder space 34, in addition to

To supply pressure medium from the second supply line 4 and thus from the second hydraulic pump 10, a bypass valve 46 is provided. This is about one

Branch line 48 connected to the first working line 38. About a second

Supply line 50, the bypass valve 46 is connected to the second supply line 4. For the connection of the branch line 48, the bypass valve 46 has a working port A and for the supply line 50 a pressure port P. The bypass valve 46 is a proportionally adjustable 2/2-way valve. Its valve slide is in the direction of a locking position 0 with a spring force of a valve spring 52 and in the direction of a working position a with a

Control pressure acted upon via a control line 54. In the blocking position 0, the pressure medium connection between the second supply line 4 and the branch line 48 is blocked and opened in the working position a. The valve spool can of course be operated pneumatically or electromagnetically against the spring force of the valve spring 52 in the direction of the working position a. If the valve spool of the main directional valve 36 in its working positions b and the valve spool of the bypass valve 46 in its working positions a, the cylinder chamber 34 of the hydraulic cylinder 26 can be supplied to the maximum flow rate of both the first hydraulic pump 6 and the second hydraulic pump 10. By the bypass valve 46 thus takes place a summation of

Flow rates of the hydraulic pumps 6 and 10. Flow losses here are advantageously extremely low, since in the summation both the pressure medium from the first supply line 2 and from the second supply line 4 must flow only via a directional control valve 36 and 46 respectively.

In order to load-hold the hydraulic cylinder 26, a check valve 56 or 58 is assigned to both the main directional control valve 36 and the bypass valve 46. The check valve 56 is arranged in the first supply line 42 between the main directional control valve 36 and the first supply line 2 and opens in a pressure medium flow direction to the main directional valve 36. The other

Check valve 58 is disposed in the branch line 48 between the bypass valve 46 and the working line 38 and opens in a pressure medium flow direction away from the bypass valve 46.

In FIG. 2, in addition to the first main-way valve 36 and the first bypass valve 46, the valve block 1 has a second main-way valve 60 and a second one

By-pass valve 62 for supplying pressure medium of another hydraulic

The second main-way valve 60 controls a pressure medium connection between the second supply line 4 and the hydraulic cylinder 64 and the bypass valve 62 a pressure medium connection between the first supply line 2 and the hydraulic cylinder 64. The second main and Nebenwegeventil 60 and 62nd are according to the first main and

By-pass valve 36, 46 configured.

In a supply line 66 between the second supply line 4 and the second main-way valve 60 is in the pressure fluid flow direction to the

Main way valve 60 opening check valve 68 is provided. Another one Check valve 70 is provided in a branch line 72 between the bypass valve 62 and the working line 74.

The main way valve 36 and the bypass valve 46 together with their

Check valves 56 and 58 and the working ports A1 and A2 for the

Hydraulic cylinders 26 are provided in a first valve half 76 of the valve block 1. In a second valve half 78 then the main way valve 60, the bypass valve 62, the check valves 68, 70 and the working ports A1 and A2 for the

Hydraulic cylinder 64 is provided. The first supply line 2 thus serves for the first

Valve half 76 to the primary pressure medium supply, in which case the second

Supply line 4 is used for summation. Conversely, the second serves

Feed line 4 in the second valve half 78 as the primary pressure medium supply and the first supply line 2 then to the summation.

FIG. 3 shows the valve block 1 from FIG. 1 with a further main directional valve 80 and a further bypass valve 82. The main directional valve 80 is designed in accordance with the first main directional valve 36 and controls a pressure medium connection between the first supply line 2 and a hydraulic consumer in the form of a hydraulic cylinder 84. The bypass valve 82 also corresponds to the first bypass valve 46 and controls accordingly a pressure medium connection between the second supply line 4 and the hydraulic cylinder 84. In contrast to

Embodiment of Figure 1 is further in both the supply line 42 of the first main-way valve 36 and in a supply line 86

Main way valve 86 each have a prioritization valve 88 and 90, respectively. These are each arranged in the pressure medium flow path between the check valve 56 of the supply line 42 and a check valve 92 of the supply line 86 and the first supply line 2. The prioritization valves 88 and 90 are designed as proportionally adjustable 2/2-way valves. The valve spool is in each case acted upon via a spring force of a valve spring 94 or 96 in the direction of a working position a, in which a pressure medium connection between the first supply line 2 and the respective main directional control valve 36 or 80 is opened. Over a

Control line 98 or 100, the respective valve spool of the prioritization valve 88 and 90 in the direction of a locking position 0 is displaceable. In this is the Pressure fluid connection between the main directional valve 36 and 80 and the first supply line 2 is interrupted. The valve spool of the prioritization valves 88 and 90 can also be moved, for example, pneumatically or electromagnetically, instead of the hydraulic actuation by the control line 98 and 100.

By the hydraulic arrangement according to Figure 3, the hydraulic

Consumers or hydraulic cylinders 26 and 84 primarily supplied via the first supply line 2 with pressure medium. The second supply line 4 then serves together with the

Secondary valves 46 and 82 for summation. If one of the hydraulic cylinders 26 or 84 is to be prioritized, it will simply be a flow cross section of the other one

Hydrozyl inders 26 and 84 is narrowed or closed via the prioritization valve 88 or 90 associated therewith.

In FIG. 4, in addition to the hydraulic cylinders 26 and 64, a first and second hydraulic motor 102 and 104 are connected to the valve block 1 as additional consumers. The upper hydraulic cylinder 26 in the figure is connected to the first supply line 2 via its main directional control valve 36 and the priority valve 88 associated therewith. About its bypass valve 46, the hydraulic cylinder 26 with the second supply line 4 in fluid communication. By contrast, the hydraulic cylinder 64 is connected with its bypass valve 62 to the first supply line 2 and via its main directional control valve 60 and a prioritizing valve 106 associated therewith to the second supply line 4. The hydraulic cylinder 26 with its main way valve 36, bypass valve 46 and

Prioritizing valve 88 is assigned to the first valve half 76. The other hydraulic cylinder 64 with its main directional valve 60, its bypass valve 62 and its prioritization valve 106 is associated with the second valve half 78.

In FIG. 4, between the valve halves 76 and 78, the hydraulic pumps 6 and 10 together with the pressure relief valves 18 and 20 and the hydraulic motors 102 and 104 are provided. These can be driven in both directions of rotation. The first

Hydraulic motor 102 is in fluid communication with the first supply line 2 via a main directional control valve 108. The main way valve 108 is hereby proportional

adjustable 4/3-way valve designed. It has two working ports A1 and A2 to which the first hydraulic motor 102 is connected. Furthermore, the Main way valve 108 has a pressure port P and a tank port TA. In the middle position 0 of the valve spool of the main directional control valve 108 are the two

Working ports A1 and A2 connected to the tank port TA, whereby the first hydraulic motor 102 to the tank T is depressurized. Starting from its middle position 0, the valve slide is displaceable on the one hand in the direction of working positions a in which the pressure port P is connected to the working port A1 and the working port A2 to the tank port TA, whereby the hydraulic motor 102 can be driven in a first direction of rotation. Furthermore, the valve spool of the

Main way valve 108 are proceeding from the middle position 0 in working positions b in which the pressure port P is connected to the working port A2 and the working port A1 to the tank port TA and thus the

Hydraulic motor 102 can be driven in the opposite direction of rotation.

The second hydraulic motor 104 is also connected to a main directional valve 110 in accordance with the first hydraulic motor 102. This is designed according to the main directional valve 108. The main way valve 1 10 is in this case via its pressure port P to a working port A1 of a straight-travel valve (ST valve) 1 12th

connected. This serves to be the second hydraulic motor 104 via

Main way valve 1 10 either to the first or second feed line 2, 4th

to join. Furthermore, a pressure medium flow path of the first runs

Feed line via the ST valve 1 12. In this case, the first feed line 2 has a first feed line section 1 14, which is connected to a working port A3 of the ST valve 1 12 and another second feed line section 1 16 to a working port A2 of the ST valve 1 12 is connected. The first

Supply line 2 is thus through the ST valve 1 12 in a first and second

Feed line section 1 14, 1 16 divided into two. To a further working port A4 of the ST valve 1 12 is connected via a branch line 1 18, the second supply line 4. The proportionally adjustable designed as a 4/2-way valve ST valve 1 12 has a valve spool which is acted upon by a spring force of a valve spring 120 in the direction of working positions a, in which the working ports A2 and A3 and the working ports A1 and A4 are interconnected. Thus, in the working positions a, the two feed line sections 1 14, 1 16 together in

Pressure medium connection and the main directional valve 1 10 of the second hydraulic motor 104 is connected to the branch line 1 18 via a connecting line 122 which is connected between the working port A1 of the ST valve 1 12 and the pressure port P of

Main way valve 1 10 is connected. Via a control line 124 is the

Valve slide of the ST valve 1 12 against the spring force in the direction of

Working positions b either hydraulically, pneumatically or electromagnetically displaceable. In these, the working port A2 is connected to the working port A4 and the working port A1 to the working port A3. Thus, the first supply line section 1 14 with the connection line 122 and the second

Zuführleitungsabschnitt 1 16 with the branch line 1 18 and thus with the second

Feed line 4 in pressure medium connection.

In the following, the operation of the ST valve 1 12 is explained in more detail. Is the

Valve block 1 of Figure 4 used for example for an excavator, so the first hydraulic motor 102 as a drive for a first, for example, left excavator side and the second hydraulic motor 104 as a drive for a second, for example, right

Be used on the excavator side. As long as the excavator no superimposed movement of the two traction drives or hydraulic motors 102 and 104 with one of the other

Consumers 26 and 64 to be made, so are the or the consumer 26 of the first valve half 76 and the drive or hydraulic motor 102 of the first excavator side primarily by the hydraulic pump 6 and the or the consumer 60 of the second

Valve half 78 and the drive or hydraulic motor 104 of the second excavator side primarily supplied by the second hydraulic pump 10 with pressure medium. The summing function takes place in each case via the other pump 6 or 10.

If, on the other hand, a superimposed movement takes place, then the valve slide of the ST valve 1 12 is displaced in the direction of the working positions b, so that the travel drives or hydraulic motors 102 and 104 through the first hydraulic pump 6 and all other consumers 26, 64 through the second hydraulic pump 10 are supplied with pressure medium. In this case, even with partial control of the ST valve 1 12 pressure equalization between the two traction drives or hydraulic motors 102 and 104 must be ensured, so that in particular ensures a straight ahead of the excavator and unintentional cornering is excluded. That's why one is Summing over the bypass valves 62 and 46 are not provided in this operating condition.

In FIG. 5, the valve block 1 is shown by way of example together with the hydraulic cylinder 26, the main directional valve 36 and the bypass valve 46 from FIG. in the

In contrast to the preceding embodiments from FIGS. 1 to 4, they are provided in parallel with the pressure-limiting valves 18 and 20 open-center valves (OC valve) 126, 128. The OC valves 126 and 128 each have a pressure port P and a tank port TA. To a respective pressure port P is in this case a branch line 130 and 132 connected, which in turn is connected to the pressure line 22 and 24 and thus is in pressure medium connection with the first or with the second supply line 2 and 4 respectively. To the tank connections TA a common tank line 134 is connected, which is connected to the tank T. The OC valves 126 and 128 are proportionally adjustable 2/2-way valves. A respective valve slide is in this case via a valve spring 136 or 138 with a

Spring force acted upon in the direction of working positions a, in which the

Pressure port P is connected to the tank connection TA. Via a control line 140 or 142, a respective valve slide in the direction of blocking positions 0 is displaceable, in which the pressure port P is separated from the tank port TA. The valve spool can of course also be adjusted pneumatically or electromagnetically against the spring force.

The OC valves 126 and 128 serve to ensure that when all valve spool the

Main way valves of the valve block 1 in a middle position or blocking position are zero, which can flow from the hydraulic pumps 6 and 10 funded pressure medium flow directly to the tank T. Now, if the valve spool of a main directional control valve and / or by-pass valve adjusted in working positions, the OC valve 126 and 128 is controlled, which is connected to that supply line 2 or 4, then from the pressure medium through the main way valve and / or bypass valve to flow. If, for example, according to FIG. 5, the valve slide of the main directional valve 36 is moved in the direction of its working positions b, the valve slide of the OC valve 126 is displaced in the direction of the blocking positions 0. As a result, a jam pressure in the first supply line 2 is generated, which is responsible for the movement of the consumer or Hydraulic cylinder 26 is necessary. By the hydraulic arrangement according to Figure 5 is advantageously known from the prior art classical

Throttle control for open-center systems readjusted, for example, in which a valve spool of a 6/3-way valve has a neutral position open in the neutral position, which is throttled when the valve spool is actuated to generate a necessary load pressure, which further a load sensitivity of the system can be adjusted ,

According to Figure 6, the valve block 1 is exemplified again with the hydraulic cylinder 26, the main directional control valve 36 and the bypass valve 46, wherein

Pressure medium source adjustable hydraulic pumps 140 and 142 for the first and second supply line 2 and 4 are provided. The hydraulic pumps 140 and 142 are thus demand-controlled as a function of the switching positions of the valve spool of the main and Nebenwegeventile of Figures 1 to 6. This leads to energy advantages, since not permanently a maximum pressure medium delivery volume must be promoted.

In Figure 7, the valve block 1 is an example according to the figure 1 with the

Hydraulic cylinder 26, the main way valve 36, the bypass valve 46, the

Hydraulic pumps 6 and 10 shown. In addition, a respective working line 38 and 40 between the hydraulic cylinder 26 and the main way valve 36 with a

Pressure limiting valve 144 and 146 connected. Thus, the

Consumer connections A1 and A2 or the working lines 38 and 40, respectively

druckabgesichert. It is conceivable that only one of the working lines 38 and 40 is connected to a pressure relief valve. Such pressure relief valves can be used for all working connections of consumers or for selected

Work connections should be provided.

FIG. 8 shows a central valve block section 152. The first and second pump ports P1 and P2 are formed on the pump port P1, the adjustable hydraulic pump 140 is connected via the pump line 8 and the second adjustable hydraulic pump 142 is connected to the pump port P2 via the pump line 12. The hydraulic pumps 140 and 142 are driven via a common drive shaft 154 by a drive unit, not shown. From the pump connections P1 and P2 in the central valve block section 152, the first and second supply lines 2 and 4, respectively, extend as channels. The central valve block section 152 has to

Flanges of further valve block sections a first and a side facing away from this second valve block side 156 and 158. The second supply line 4 opens both in the first and in the second valve block side 156 and 158, each with a line connection L1 'and L1. "The first supply line 2 opens also in the second valve block side 158 with a line connection L2 'and is connected with its first supply line section 1 14 with the ST valve 1 12. Der zweite

Feed line section 1 16 then opens in the first valve block side 156 with a line connection L2 ". The ST valve 1 12 is in accordance with Figure 8 in the direction of his

Working positions a with the spring force of the valve spring 120 acted upon. In the direction of the working positions b, the ST valve 1 12 is in this case via an actuator

Electromagnetically actuated. Thus, this operation is not hindered by leakage oil, the spring chamber of the valve spring 120 via a drain line 160 with a

Leakage oil connection L connected. To the ST valve 1 12, the main directional valve 1 10 is further connected to control the first hydraulic motor 104. The hydraulic motor 104 is connected via a first working line 162 to a working connection A1 and via a second working line 164 to a working connection A2 of the central one

Valve block section 152 connected. In the pressure medium flow path between the

Working ports A1 and A2 and the main directional valve 1 10 is one

Pressure limiting valve 144 and 146 provided in accordance with Figure 7. These open from a certain pressure a pressure medium connection to a central

Valve block section 152 completely penetrating tank channel 170. The tank channel 170 opens in this case in a respective valve block side 156 and 158 with tank ports T1 and T2. The central valve block section 152 is additionally of another

Tank passage 172 completely penetrated, which also opens in both valve block sides 156 and 158 with a tank port T1 and T2.

The first hydraulic motor 102 is connected via working lines 174 and 176 to working ports A1 and A2 of the central valve block section 152. The working ports A1 and A2 are assigned to the main directional control valve 108, see also FIG. 4. To limit the pressure also branches again from the pressure fluid flow paths between the working ports A1 and A2 and the main directional control valve 108th Pressure relief valves 144 and 146 from. Valve spool of the main directional control valves 108 and 1 10 are spring-centered according to Figure 8 via valve springs 178 and 180 in its center position. Such spring centering can be provided for all main way valves.

Further, in the central valve block section 152, the OC valves 126 and 128 are arranged. The valve spool is in this case according to the figure 5 on the

Valve springs 136 and 138 acted upon by a spring force. In the opposite direction, the valve spool of the OC valves 126 and 128 are electromagnetically actuated.

So that this operation is not hindered by leakage oil, the spring chambers of the valve springs 136 and 138 are connected via a leak oil line 161 with a leakage oil connection L.

Furthermore, the pressure limiting valves 18 and 20, see also FIG. 1, are formed in the central valve block section 152. For the control lines of the

Main way valves 108 and 110, the central valve block section 152 has a plurality

Control connections S.

The central valve block section 152 has according to Figure 8, the control for both hydraulic motors 102 and 104 and thus for both traction drives of the excavator. For example, it would be conceivable alternatively to provide the control for the hydraulic motor 102 in a standardized valve disk with a special drilling variant.

FIG. 9 shows a further, in particular standardized, valve block section 182. This is sent to the central valve block section 152, preferably to the first valve block section 152

Valve block side 156, flanged with its valve block side 184. On the valve block side 184, two tank ports T1 and the two line ports L1 ^" and L2 ^" are then provided corresponding to the valve block side 156 of FIG. The valve block section 182 further includes a second one facing away from the valve block side 184

Valve block side 186, which has correspondingly the terminals T1, L1 ^" and L2 ^" . On the valve block side 186, a closure plate 188 is then flanged according to FIG. This is designed such that it connects the tank connections T1 and thus the tank channels 170 and 172 with each other. The valve block section 182 in FIG. 9 is completely penetrated by the supply lines 2 and 4, which are formed as channels, with the supply lines 2 and 4 approximately parallel with each other and approximately parallel to the tank channels 170 and 172 between the valve block sides 184 and 186 extend. To the first supply line 2, which is connected to the second supply line section 16 of FIG. 8, the main directional control valve 36 is connected via the prioritization valve 88. The main directional valve 36, the working ports A1 and A2 of the valve block section 182 are assigned, to which the hydraulic cylinder 26 is connected. Via the bypass valve 46, the hydraulic cylinder 26 is connected to the second supply line 4, which is connected to the second supply line 4 of FIG. To the pressure medium flow paths between the hydraulic cylinder 26 and the main way valve 36 are the

Pressure relief valves 144 and 146 connected.

The further hydraulic cylinder 84 is also at working ports A1 and A2 of

Valve block section 182 connected and via the main directional control valve 80 and the prioritization valve 90 to the first supply line 2 and via the bypass valve 82 to the second supply line 4 in fluid communication. In addition, the pressure relief valves 144 and 146 are again provided.

Optionally, another hydraulic consumer can be connected to working ports A1 and A2 of the valve block section 182. These working ports are connected to the first supply line 2 via a main directional control valve 190 and a prioritizing valve 192 corresponding to the hydraulic cylinders 26 and 84, and to the second supply line 4 via a bypass valve 194. Furthermore, the

Working ports A1 and A2 again associated with the pressure relief valves 144 and 146.

For controlling the main directional control valves 36, 80, 190, the by-pass valves 46, 82, 194 and the prioritizing valves 88, 90, 192, the valve block section has the control ports S. The hydraulic cylinder 26 of Figure 9 is used for example for a boom of the excavator and the hydraulic cylinder 84 for a spoon of the excavator. FIG. 10 shows a further, in particular standardized valve block section 196. It can be flange-mounted via its valve block side 198, in particular to the valve block side 158 of the central valve block section 152 from FIG. For this purpose, the tank connections T2 and the line connections L1 ^' and L2 ^{' are} provided on the valve block side 198. At the side facing away from the valve block side 198 valve block side 200 of

Valve block section 196 is also a closure plate 202 is provided according to the figure 9, which connects the tank ports T2 together and the

Line connections L1 ^' and L2 ^' terminates.

The valve block section 196 is completely penetrated by the supply lines 2 and 4 which are designed as channels and extend approximately parallel to one another. These also extend approximately at a distance parallel to the tank lines 170 and 172, which also fully enforce the valve block section 196. To the

Valve block section 196 is connected via working ports A1 and A2 of the hydraulic cylinder 64, see also FIG. 4. This can be connected via its main directional control valve 60 and the prioritization valve 106 to the second supply line 4. Be over

By-pass valve 62, it is connectable to the first supply line 2. to

Pressure limiting the working ports A1 and A2, the pressure relief valves 144 and 146 are provided.

Further, in the valve block section 196, one is in both directions of rotation

operable hydraulic motor 204 is provided and connected to working ports A1 and A2 of the valve block section 196. Via a main way valve 206 and a

Prioritization valve 208, the hydraulic motor 204 with the second supply line 4 is connectable. To limit the pressure of the working ports A1 and A2 for the hydraulic motor 204, the pressure limiting valves 144 and 146 are provided.

The hydraulic cylinder 64 from FIG. 10 is associated, for example, with a handle of the excavator, and the hydraulic motor 204 is used, for example, to turn one

Turning device of the excavator.

It is conceivable that the valve block sections shown in FIGS. 9 and 10 can be completely or partially inserted into the central valve block section 152 from FIG. 8 For example, if the elements listed therein can not be represented by a standard valve disc.

According to FIG. 11, a cross-section in the region of the main directional control valve 36 is represented by the valve block section 182 from FIG. In this case, a continuous slide bore 210 is provided, in which the valve slide 21 1 of the main directional control valve 36 is slidably guided. In the slide bore 210, a first annular space 212 is formed centrally, which is connected to the supply line 42 formed as a channel. The supply line 42 extends in this case away from the spool bore 210 in the figure 1 1 down. Adjacent to the supply line 42 is the first

Feed line 2 as shown in the drawing plane of Figure 1 1 extending channel. Between the first supply line 2 and the first supply line 42, the prioritization valve 88 and the check valve 56 are provided, which are shown symbolically in FIG. 11. In each case adjacent to the annular space 212, two further annular spaces 214 and 216 are provided in the slide bore 210. The one annular space 214 serves as the working port A1 and the other annular space 216 as the working port A2. The annular spaces 214 and 216 are each connected to a working line 218 or 220 designed as a channel. These extend away from the spool bore 210 approximately in the opposite direction as the

Supply line 42 toward those formed in the valve block section 182

Work connections A1 and A2. In turn, adjacent to the annular spaces 214 and 216, an annular space 222 and 224 is formed in the spool bore 210, respectively. These are in each case connected to tank lines 226 and 228 designed as tank. The annular space 216, which is connected to the working port A2, is additionally connected to the branch line 48 formed as a channel. This extends adjacent to the first supply line 42 away from the spool bore 210. About the symbolically shown by-pass valve 46, the branch line 48 is connected to the second supply line 4, which extends in parallel distance to the first feed line 2 in the direction of the plane in Figure 1 1. Furthermore, it is still symbolic

Check valve 58 shown. To the working lines 218 and 220 are the

Pressure limiting valves 144 and 146 connected, which are also shown symbolically and further connected to the tank line 226 and 228, respectively. The valve spool 21 1 has to control a connection of the annular spaces 212 to 224, a central control collar 230 and two adjacently formed control cords 232 and 234. In the shown center position of the valve spool 21 1 is a

Fluid connection between the annular spaces 212 to 224 locked. If the valve spool 21 1 moves from the center position shown to the right in the working positions b, then via the central control collar 230, a pressure medium connection between the middle annular space 212 and the adjacent annular space 214 and thus a pressure medium connection between the working port A1 and the first

Supply line 2 open. Furthermore, a pressure medium connection between the other annular space 216 adjacent to the middle annular space 212 and the annular space 224 connected to the tank line 228 is opened, as a result of which

Working port A2 is connected to the tank. If the valve slide 21 1, however, shifted from its central position to the left in the direction of the working positions a, the middle annulus 212 is connected to the adjacent annular space 216 and the other adjacent annulus 214 to the annular space 222, which on the one hand a pressure medium connections between the working port A2 and the first one

Supply line 2 and the working port A1 is opened with the tank. Via the auxiliary valve 46, the annular space 216 and thus the working port A2 can be connected to the second supply line 4 in any position of the valve spool 21 1.

Disclosed is, in particular according to the invention, a hydraulic arrangement with a valve block, which is designed such that two pressure medium sources can be connected. A main-way valve of the valve block is a pressure medium connection between a consumer connected to the valve block and the first

Pressure medium source and controllable between the consumer and a pressure medium sink. Advantageously, the second is additionally via a bypass valve

Pressure medium source fluidly connected to the consumer. List of Reference Valve Block

first supply line second supply line hydraulic pump

pump line

hydraulic pump

pump line

tank line

Pressure relief valve Pressure relief valve Pressure line

pressure line

hydraulic cylinders

piston

piston rod

annulus

cylinder space

Main way valve

working line

first supply line control line

Next-way valve

branch line

second supply line valve spring

control line

check valve

check valve second main-way valve second bypass valve hydraulic cylinder

supply line

check valve

branch line

working line

first valve half

second valve half

Main way valve

Next-way valve

hydraulic cylinders

supply line

prioritizing valve

check valve

valve spring

control line

first hydraulic motor

second hydraulic motor

prioritizing valve

Main way valve

Straight-travel valve first supply line section second supply line section branch line

valve spring

connecting line

control line Open center valve open center valve branch line

branch line

tank line

valve spring

Adjustable hydraulic pump Adjustable hydraulic pump Pressure relief valve Pressure relief valve Central valve block section Drive shaft

first valve block side second valve block side Leakage oil line

Drain line

working line

tank channel

working line

valve spring

further valve block section valve block side

Manifold Page

closing plate

Main way valve

Prioritization valve by-pass valve further valve block section 98 Valve block side 00 Valve block side

02 closure plate

04 hydraulic engine

06 main way valve

08 Prioritization valve

10 slide bore

1 1 valve spool

212 annulus

214 annulus

216 annulus

218 work management

220 work management

222 annulus

224 annulus

226 tank line

228 tank line

230 tax code

232 tax code

234 tax code

P1, P2 Pump connection A, A1, A2 working connection

T tank

TA, T1, T2 tank connection

L leakage oil connection

0 blocking position

a, b working position

Ι_, Ι_ \ L2 \ L2 ^"Le ^{'itungsanschluss}

S control connection

Claims

claims

Valve block for controlling at least one consumer (26), wherein the valve block (1) has a first and second supply line (2, 4), each in a pump port (P1, P2) of the valve block (1) open and via the pump connections ( P1, P2) can be connected to a respective pressure medium source (6, 10), and wherein for connecting the load (26) a first and second working port (A1, A2) is provided on the valve block (1), wherein a main way valve (36 ) a respective working port (A1, A2) or both working ports (A1, A2) with the first supply line (2) or a tank line (T) are fluidically connectable, characterized in that via a bypass valve (46) a pressure medium connection between the second

Supply line (4) and the first working port (A1) is controllable.

Valve block according to claim 1, wherein the bypass valve (46) to a

Pressure medium flow path (38) between the main directional control valve (36) and the first working port (A1) is connected.

Valve block according to claim 2, wherein the main way valve (36) via a first supply line (42) to the first supply line (2) and the bypass valve (46) via a second supply line (50) to the second supply line (4) and via a working line ( 48) to the pressure medium flow path (38)

is connected, and wherein in the first supply line (42) a first and in the second supply line (48) or in the working line (50) a second check valve (56, 58) is provided, each in a

Open the pressure medium flow direction towards the consumer (26)

Valve block according to one of claims 1 to 3, wherein a first and second working port (A1, A2) for a second consumer (64) and a second main way valve (60) are provided, via which a pressure medium connection between a respective working port (A1, A2). or both

Working ports (A1, A2) for the second consumer (64) and the second supply line (4) or the tank line (T) is controllable, and wherein via a second bypass valve (62) a pressure medium connection between the first supply line (2) and the first working port (A1) for the second

Consumer (64) is controllable.

5. Valve block according to one of claims 1 to 4, wherein a first and second

Work connection (A1, A2) for a further consumer (84) and another main way valve (80) is provided, via which a respective working port (A1, A2) or both working ports (A1, A2) for the further consumer (84) with the first supply line (2) or a tank line (T) are fluidically connectable, and wherein a further bypass valve (82) a

Pressure medium connection between the second supply line (4) and the first working port (A1) of the further consumer (84) is controllable, wherein the further main way valve (80) via a first supply line (86) to the first supply line (2) is connected, wherein in at least one of the first

Supply lines (42, 86) of the main directional control valves (36, 80)

Prioritization valve (88, 90) is provided.

6. Valve block according to one of the preceding claims, wherein a first and second working port (A1, A2) for a first hydraulic motor (102) via a further main way valve (108) with the first supply line (2) or the

Tank line (T) are connectable, and wherein a first and second

Working port (A1, A2) for a second hydraulic motor (104) via another main directional control valve (1 10) with a straight-travel directional control valve (ST-way valve) (1 12) or the tank line (T) are connected, said on the ST -Wegeventil (1 12) the main way valve (1 10) of the second hydraulic motor (104) with either the first or second supply line (2, 4) is connectable, wherein in connecting the main directional valve (1 10) of the second hydraulic motor (104) the first supply line (2), the second main way valve (36) of the consumer (26) via the ST-way valve (1 12) to the second supply line (4) and otherwise to the first supply line (2) is connected.

7. Valve block according to one of the preceding claims, wherein to a respective supply line (2, 4) an open-center valve (OC valve) (126, 128) connected is, via which a pressure medium connection between the respective supply line (2, 4) and a tank (T) is controllable.

8. Valve block according to one of the preceding claims, wherein the to the

Pump connections (P1, P2) connected to hydraulic pumps (6, 8)

are demand-driven.

9. Valve block according to one of the preceding claims, wherein in

Pressure medium flow path between a working port (A1, A2) at least one consumer (26) and the main directional control valve (36) associated therewith, a pressure relief valve (144, 146) is connected

10. Valve block according to one of claims 7 to 9, wherein in a central

Valve block section (152) of the valve block (1) the pump ports (P1, P2), the supply lines (2, 4), the tank line (T), the OC valves (126, 128), a first and second pressure relief valve (18, 20 ) for the first and second

Supply line (2, 4), the ST-way valve (1 12) and the main way valve (108) for the first hydraulic motor (102) are provided.

1 1. Valve block according to claim 10, wherein a further valve block section (182) which can be connected to the central valve block section (152) is provided, which the

Feed lines (2, 4), the tank line (T), at least one main and

By-pass valve (36, 46) for a consumer (26), the check valves (56, 58) associated with the main and by-pass valve (46, 36), the

Piorisierungsventil (88) and the pressure relief valves (144, 146) for the working ports (A1, A2).

12. Valve block according to claim 10 or 1 1, wherein the central and / or the further valve block section (152, 182) with a closure plate (186, 202) are lockable.

13. Valve block according to claim 1 1 or 12, wherein a further to the central

Valve block section (152) connectable valve block section (196) is provided.

14. Valve block according to one of claims 1 1 to 13, wherein the main directional valve (1 10) is provided for the second hydraulic motor (104) in the central valve block section (152) or in the valve block section (182, 196) arranged adjacent to the central valve block section ,