DE102017213118A1 - Valve block assembly and method for a valve block assembly - Google Patents

Abstract

Disclosed is a valve block assembly with a valve block having at least two main spool, which are each used to control a consumer. A respective main slide is in this case connected to two electrically adjustable hydraulic machines.

Description

Field of the invention

The invention relates to a valve block assembly and a method of controlling the valve block assembly.

Background of the invention

Mobile construction machines are known from the prior art, such as excavators, which have a hydraulic system. In this case, a fixed assignment of individual hydraulic pumps to certain consumers is usually provided. Some of the consumers can also be supplied by two hydraulic pumps. In this case, a hydraulic pump is then usually provided as the main pump and the other hydraulic pump as the summation pump. The disadvantage here is that a supply by the summation pump with simultaneous operation of several consumers is energetically inefficient.

From the DE 10 2012 218 428 A1 a valve block is disclosed which can be used in a construction machine. This has a large number of main valves for controlling consumers. A respective main slide can in this case be supplied in parallel via a first and second pump channel with pressurized fluid. The respectively flowing from the pump channels fluid flow is controlled with an associated first and second auxiliary slide.

Disclosure of the invention

In contrast, the invention has for its object to provide a valve block assembly over which consumers can be controlled efficiently with a high degree of flexibility and device-wise simple way. In addition, it is the object of the invention to provide a method for a valve block assembly with which consumers can be controlled in a simple and efficient manner.

The object with regard to the valve block assembly is achieved according to the features of claim 1 and with regard to the method according to the features of claim 8.

Advantageous developments of the invention are the subject of the dependent claims.

According to the invention, a valve block arrangement is provided with a, in particular closed center, valve block. This can have at least two, in particular electrically or electrohydraulically or hydraulically controllable, main slide or main valve spool. These are each used to control a hydraulic consumer. A respective main slide can in this case be assigned at least one pressure connection and at least one working connection. Furthermore, two hydraulic machines with adjustable flow rate, in particular two electrically adjustable hydraulic machines, may be provided, which are each connected to a respective pressure port. It is also conceivable alternatively to provide hydraulically adjustable hydraulic machines.

This solution has the advantage that this allows a variable assignment and setting of consumer-specific volume flows. This is done by suitable control of the electronically adjustable hydraulic machines and the control of the main slide. Furthermore, it is advantageous that each consumer can be efficiently supplied with more than a maximum amount of pump, since a summation of the supply volume flows of the hydraulic machines is made possible. If a required torque or a required power of a drive which can be driven by the hydraulic machine is less than required, a consumer-specific limitation of the supply volume flow can be achieved by the valve block arrangement according to the invention. Thus, a free and in operation flexible change of assignment of supply volume flows for the respective consumer is possible.

Closed-center systems are a hydraulic circuit in which directional control valves are closed to control consumers in their middle position. The volume flow is then routed with closed directional control valves usually via a circulation valve when using constant displacement pumps as the pressure medium source. In an open center system, a hydraulic circuit is provided in which series-connected directional valves for controlling consumers in their middle position for the oil flow are open, so that a pump flow of a constant pump can be passed through all directional control valves. If only one directional control valve is provided, the pressure medium volume flow to the tank can be directed in its middle position, this being referred to as neutral circulation.

The valve block is preferably used as RCS (MCV) mobile control block.

In a further embodiment of the invention can be provided in that one of the main spools or at least part of the main spool or a respective main spool is fluidically assigned between the pressure port and a connected hydraulic machine, in particular electrically or hydraulically adjustable and / or controllable throttle. As a result, a flexibility for setting a volume flow distribution is further increased. Alternatively or additionally, it is also conceivable that one of the main spool or at least part of the main spool or a respective main spool is fluidically associated between the pressure port and the corresponding other hydraulic machine one, in particular electrically or hydraulically, adjustable and / or controllable throttle. This leads to a further improvement of a volume flow distribution between the consumers, whereby the flexibility is further increased. Thus, the variable allocation and the adjustment of the consumer-specific volume flows can be further improved by the proportionally adjustable throttles. It is conceivable for cost reasons instead of one or more throttles to provide a check valve which blocks in the direction of the associated hydraulic machine. The throttles can be arranged in fluidic parallel and be connected to one each with the respective associated main spool and the other with the hydraulic machine.

In a further embodiment of the invention, it can be provided that a bypass flow path branches off fluidically between the pressure connections and the one hydraulic machine. This can then be connected via a, in particular electrically or hydraulically, adjustable and / orangesteuert cut valve with a tank or a low pressure side and be throttled over this. This has the advantage that with the cut valve, a desired load dependency or load sensitivity can be implemented, as provided in an open center system. Since the cut valve, in particular electrically, is adjustable and / or driven, an opening cross-section of the cut valve can be determined flexibly. The smaller the opening area of the cut valve, the stiffer the hydraulic system and the lower the load. For example, if the main spool is used to control a bucket of a shovel and the bucket strikes a pipe during operation, for example, the speed of the bucket would become significantly lower at high load sensitivity. An excavator operator would recognize that the bucket is hit by an obstacle due to the lower speed of the bucket, thus allowing it to "feel" the load. At low load sensitivity, ie at a comparatively small opening cross-section of the cut valve, the speed of the blade movement, for example, when hitting the tube, would not or not substantially or only slightly changed, which may not notice the excavator driver this circumstance. As a result, then there is a low load sensitivity for the excavator driver. Thus, by the, in particular electrically, adjustable and / or controllable cut valve on device-simple manner, the desired load dependence as done in an open center system.

In a further embodiment of the invention can branch off fluidically between the pressure ports and the other hydraulic machine, a bypass flow path. This can then be connected to the tank via a further, in particular electrically, adjustable and / or controlled cut valve and throttled over this. This can further improve open center behavior.

The main slide or at least one of the main slides or a part of the main slides or all the main slides can preferably be assigned a tank connection and / or a further working connection in addition to the pressure connection and the working connection. For example, pressure fluid can then flow away from the consumer via the tank connection. By further working connection is conceivable as a consumer to provide a double-acting cylinder. Preferably, it is provided in the main slide or a part of the main slide or in all main slides that they are continuously adjustable. An actuation degree of the main spool or the individual main spool can then be provided as an actuating element.

In a preferred embodiment, a main slide in a, in particular spring-centered, middle position can be brought, in which the main slide associated ports are separated from each other. Starting from the middle position, the pressure connection with the first working connection and the tank connection with the second working connection can be connected when the main slide is displaced in the direction of first switching positions. When moving the main slide starting from the middle position in the direction of second switching positions, wherein the direction is opposite to the first switching positions, then the pressure port can be connected to the second working port and the first working port to the tank port. To adjust the main spool, a valve spool control or an actuator is provided. In this case, a first actuator can be used for a first adjustment direction and a second actuator can be used for a second adjustment direction. Other main slides can be designed accordingly. A main spool with two working connections, a pressure connection and a tank connection can be part of a 4/3-way valve. The one or both throttles, which may / may be associated with a main spool, can then be provided as a valve subassembly (s).

In a further embodiment of the invention, the cut valve or a respective cut valve can be steadily openable and controllable in order to flexibly adjust the load sensitivity. Preferably, the cut valve or a respective cut valve is open in a basic position, whereby the hydraulic machine is connected to the tank. In the direction of the basic position can a Valve spool of the cut valve to be acted upon with a spring force of a valve spring. Opposite can then be moved via a valve spool control or via an actuator, the valve spool of the cut valve in the direction of closed positions.

In a further embodiment of the invention, one of the hydraulic machines as the main pump and the corresponding further hydraulic machine can be used as a summation pump. Preferably, the hydraulic machines are volume flow controlled or pressure controlled. Downstream of a respective hydraulic machine, a pressure sensor is preferably provided. If one or both hydraulic machines are pressure-controlled, then a swivel angle sensor is preferably additionally provided for such a hydraulic machine. It is also conceivable to use one or more additional hydraulic machines in addition to the two hydraulic machines. A respective hydraulic machine can then preferably promote pressure medium from the tank to the associated main slide.

In a further embodiment of the invention, an electronic control system is provided. This may have an adaptation module or a first module. In this case, a default value can be input or fed in for a consumer or for a respective consumer or for a main slider or for a respective main slider, in particular via an input device or a respective input device. The default value or a respective default value can then be changed by the adaptation module into a customized or a respective adjusted default value. In other words, a default value can be adapted, in particular smoothed, for each consumer in the adaptation module. As an input device, for example, a joystick is provided, which can then serve as a default value a joystick signal. The default value is converted, for example, by a monotone or continuously increasing characteristic and / or by a time function, such as PT1 or PT2, into an adapted default value. By adapting the default value, signal conditioning is advantageously enabled. Preferably, a joystick is provided for the main slide. If a plurality of main slides are provided, a respective joystick can be provided for a part of the main slide or for a respective main slide.

Advantageously, one or the control electronics have a default module or second module. With this, a, in particular adapted, default value or a respective, in particular adapted, default value can be converted into a volume flow specification for the consumer or into a respective volume flow specification for a respective consumer. Furthermore, with the default module, the, in particular adapted, default value or a respective, in particular adapted, default value can be converted into one, in particular desired, load-sensing information or into one, in particular desired, respective load-sensing information for the consumer or for the corresponding consumer. Alternatively or additionally, it can be provided with the default module that the, in particular adapted, default value or the respective, in particular adapted, default value is converted into one, in particular desired, or respectively in one, in particular desired, maximum pressure. With the load sensing information is a throttle specification for the cut valve available, which then advantageously a back pressure is adjustable, with which the consumer can be supplied according to the open center principle. The flow rate specification can then specify the speed of the consumer. With the maximum pressure for a respective consumer, a high control of the hydraulic machine can advantageously be implemented as a function of the default values or actuation signals.

The volume flow for the consumer or for a respective consumer can then be taken over a map depending on the adjusted default value with respect to the corresponding consumer. Alternatively or additionally, a characteristic field can be provided for the respective load-sensing information of the consumer or of a respective consumer which is based on the (respective) adjusted default value of the consumer. Furthermore, alternatively or additionally, a map for the (respective) maximum pressure for the consumer or for a respective consumer, which is also based on the adjusted default value with respect to the consumer or the corresponding consumer, are taken. On the basis of the map or the maps can thus be implemented in a very simple manner, the default value or the default values.

In a further embodiment of the invention, the control electronics or control electronics may have an actuation module or third module. This can then generate based on the implemented default or the converted specifications of the default module, in particular electrical or hydraulic actuating signal or, in particular electrical or hydraulic, actuating signals. As actuation signal (e) can be a total volume flow specification for the hydraulic machine (s) or a pump volume flow specification for the main pump and a pump flow rate for the summation and / or a total throttle for the cut valve and / or a control variable or a respective control variable for the main slide or for a portion of the main spool or for a respective main spool and / or a control variable or a respective control variable for a Throttle or a portion of the throttles or be provided for a respective throttle. In other words, a third module may summarize the user-based input values and generate the individual actuation signals. The actuation module may further take into account a load pressure of a load or a portion of the loads or all loads for generating the actuation signal or the actuation signals to enable improved load sensing. The load pressure or the load pressures are preferably preset and are based, for example, on empirical values. Alternatively or additionally, it may be provided to detect the load pressure or the load pressures via one or more sensors. Thus, with the aid of the calculation variables of the adjusted default value and / or the maximum pressures for a respective consumer and / or the volume flow specification for a respective consumer and / or the load sensing information for a respective consumer and / or the load pressures for a respective consumer, the control variables for the Valve slide control of the main slide and / or a pump control for the at least one hydraulic machine and / or for the valve slide control of the cut valve can be calculated.

In other words, a control unit and software are provided to process setpoints or driver requests and to calculate necessary control signals.

In a further embodiment of the invention, a speed of the hydraulic machine or hydraulic machines for generating the actuation signal or the actuation signals is conceivable to be taken into account in the actuation module. In this way, a more accurate generation can be done in device-technically simple manner. The rotational speed of the hydraulic machine or of the hydraulic machines can be carried out as a predetermined parameter, for example based on empirical values, or as a measured value, which is recorded, for example, via one or more sensors. Alternatively or additionally, in the actuation module, a torque of a drive unit driving the hydraulic machine or the hydraulic machines, such as, for example, a motor or a diesel engine, may be considered in order to enable an even more accurate generation of actuation signals.

In other words, the data for the control of the individual consumers are supplied to an actuation module which can control the valves of the individual consumers, the cut valve and the pump control according to predetermined arithmetic operations.

The control via the actuating signal or the actuating signals is preferably carried out as a non-feedback control or in "Feed Forward Mode". This leads to a device technology extremely simple control.

The modules for the control electronics can be simple and cost-effective to software modules that are executed in particular on the control electronics.

The Applicant reserves the right to submit to the control electronics according to one or more of the preceding aspects, a separate independent claim. According to the invention, a method for controlling the valve block assembly according to one or more of the preceding aspects may be provided. In this case, supply volumetric flows which can be conveyed by the hydraulic machines for the consumers can be assigned individually or variably to the connected consumers by triggering the hydraulic machines with adjustable flow rate, in particular the electrically adjustable hydraulic machines, and by controlling the main slide, in particular electrically adjustable. It is conceivable in this case to support the assignment of the further by controlling the at least one cut valve.

This solution has the advantage that in this way an efficient limitation or displacement of the supply volume flows of the hydraulic machines, depending on the driver request and the available power is possible. Furthermore, by exceeding the available power or an available torque for driving the hydraulic machines, not only the supply volume flows but also the feed cross sections to the consumers can be reduced.

In a further embodiment of the method, the individual assignment of the deliverable supply volume flows for the consumers can additionally be effected by controlling the, in particular electrically, adjustable throttles. Thus, the variable assignment and the adjustment of the consumer-specific volume flows by proportional adjustment of the throttles and the electronically adjustable hydraulic machines can be flexible and variable. A part of the volume flow distribution can then be additionally represented by the, in particular electrically, adjustable main slide.

The method according to the invention thus makes it possible to control a valve and pump arrangement according to one or more of the preceding aspects, in which the assignment of the hydraulic machines to the respective consumers is made extremely efficient and easy to control.

In a preferred embodiment of the invention, a priority level, in particular from the control electronics, can be assigned to a respective consumer. The allocation of the supply volume flows to the consumers can then take place as a function of the priority levels. Thus, it is conceivable to provide separately for each individual consumer an adjustable or predeterminable priority level. For example, it may then be provided that the higher the priority level or a priority, the later the supply quantity of this consumer is reduced.

If at least two consumers are provided, then the first consumer may have the highest, in particular first, priority level and the second consumer a smaller, in particular second, priority level. It is conceivable that the priority levels for further consumers will be further scaled accordingly. If, for example, at least three consumers are provided, then the first consumer may have the highest, in particular first, priority level, the second consumer a smaller, in particular second, priority level and the third consumer an even smaller, in particular third, priority level.

Preferably, a respective volume flow specification for a respective consumer can be predetermined, in particular via a joystick. A respective volume flow specification can then, in particular via the control electronics, be assigned a respective limiting factor, via which a respective volume flow specification is then reduced if necessary in a predetermined manner. A respective consumer can thus be assigned a respective limiting factor. In a preferred embodiment of the invention, a respective, in particular desired, volume flow specification for a respective consumer can then be multiplied by the limiting factor assigned to it, in order then to obtain an actual volume flow specification for the respective consumer. A respective limiting factor is preferably between 0 and 1, or is 0 or 1. In other words, a respective limiting factor may be in a range between 0 and 1, with the limits 0 and 1 being added to the range. If a limiting factor for a consumer is greater than 0 and less than 1, then the limitation factor may depend on the power of the drive unit available for the hydraulic machine and / or on the required power of the other consumer (s) and / or on a minimum power assigned to it be calculated.

In a further embodiment of the invention, a minimum volume flow specification can be provided for a respective consumer or at least for a part of the consumer, wherein the volume flow specifications are the same or different. In other words, minimum quantities can be determined for each consumer or a part of the consumers, which are then - as far as possible - then maintained, whereby a minimum operation, such as a construction machine using the method, can be maintained. Preferably, the controller may provide one or more different modes in which predetermined limiting factors are provided to the consumers, particularly depending on their priority level. Thus, in one mode or modes, some sort of consumer limiting pattern may be provided. Thus, for example, in a simple and flexible way, a change in the allocation of the supply volume flows for the respective consumers by switching the modes can be achieved. In other words, it is possible to apply different summation strategies by means of suitable software functions.

The mode or modes may be one or more of the following modes:

In a, especially first, mode, the limiting factors may be equal to one or one. If they are one, then a volumetric flow preset that can correspond to an actual volumetric flow presetting can be provided for a respective consumer.

In a further, in particular second, mode, the limiting factor for the consumer with the highest, in particular first, priority level may be greater than the limiting factor for the consumer or the consumers with a lower priority level. This ensures that the consumer with the highest priority level is provided with an actual volume flow specification which is at least the highest or which corresponds to the desired volume flow specification if the limitation factor is 1. The volume flow specification (s) of the consumer or consumers with the lower priority level or a consumer with a lower priority level can then be reduced by the limitation factor being smaller than the limiting factor of the consumer with the highest priority level. In the case of a consumer with a smaller, in particular third, priority level, the limiting factor may result from the difference between the power available for the hydraulic machines and the power required by the further consumer or the further consumers, the difference being in a, in particular first, ratio to the required one Power is set by the consumer with the smaller, in particular third, priority level. Preferably, in the consumer with a middle, especially second Priority level of the limitation factor also 1 and / or corresponds to the limitation factor of the consumer with the highest, in particular first, priority level.

For the consumer with the smallest, in particular third, priority level, the, in particular first, ratio can then be provided as a limitation factor.

In a further, in particular third, mode, provision can be made for the consumer with the middle, in particular second, priority level to have the limiting factor 0. Thus, the limiting factor 1 is then provided, for example, for the consumer with the highest, in particular first, priority level, and the ratio, in particular the first, ratio is provided as the limiting factor for the consumer with the smallest, in particular third, priority level.

In a further preferred, in particular fourth, mode, the limiting factor may be for the consumer with the highest, in particular first, priority level 1 or at least greater than the limiting factor for the consumer or the consumers with a lower priority level. In the case of the consumer with a smaller, in particular third, priority level, the limiting factor can then be one, in particular second, ratio of a predetermined minimum power for the consumer with the smaller, in particular third, priority level for the required power from the consumer with the smaller, in particular third, priority level result. In the case of a further consumer with a likewise smaller, in particular second, priority level, the limiting factor can then be the difference between the services available via the hydraulic machine and the power required by the consumer with the highest, in particular first, priority level and that of the consumer with the even smaller one , especially third, priority level provided minimum performance. This difference can then be set in an, in particular third, ratio to the required power of the consumers with the smaller, in particular second, priority level.

In a further, in particular fifth, mode, the limiting factor for the consumer with the highest, in particular first, priority level 1 can then amount to 1 or at least greater than the limiting factor for the consumer or the consumers with a further smaller priority level. For consumers with the smaller, in particular second and third, priority level can be provided that they have a same limitation factor, this can then be formed from one, in particular fourth, ratio of a difference to a sum. The difference here may be the power available via the hydraulic machine with the required power of the consumer with the highest, in particular first, priority level. The sum can then be formed from the services of the consumers with the smaller, in particular with the second and third, priority level.

In a further, in particular the sixth, mode, it can be provided that the limiting factor for the consumer with the highest, in particular first, priority level comprises one, in particular fifth, ratio of the services available via the hydraulic machines to the consumer with the highest, in particular first, priority level required power is formed. For the consumers with the smaller, in particular second or third priority level, the limiting factor can then be 0. Thus, it can be advantageously provided in the sixth mode that the supply quantity of the consumer with the highest priority is only reduced if all other consumers have already been completely reduced. This is particularly advantageous in some special attachments that require higher safety during operation, such as with a magnet holder.

In a further embodiment of the invention, in particular as a further mode, it can be provided that the summation pump is then used when the supply volumetric flow which can be conveyed by the main pump is no longer sufficient to cover the volume flow specification (s) of the consumer or consumers. This has the advantage that the main pump is fully utilized and fully swung out before the summation pump is used, since it has been shown that a fully swung hydraulic machine has the best efficiency. In other words, the additional amount of the summation pump is dispensed with as far as possible, as long as the main pump is not yet fully utilized, which may then be a so-called implicit summation.

In a preferred embodiment, in particular in a further mode, if the available power, in particular the drive unit, for converting the Pumpenvolumenstromvorgabe for the main pump and the summation pump is not sufficient, can be provided that then the main pump the maximum or at least in Essentially promotes the maximum possible supply volume flow, and in this case in particular full or at least substantially fully swung. This is advantageous because the main pump is most efficient when fully swung out. The summation pump can then promote less or no supply volume flow. Thus, then at least the main pump works extremely efficiently.

In a further embodiment of the invention, in particular as another mode, it can be provided that at least two consumers are used as driving axles and thus, for example, each drive a chain of a tracked vehicle or crawler excavator. Furthermore, another consumer or several other consumers can be provided. In this case, one of the hydraulic machines can then be used to supply the driving axles and the other hydraulic machine can be used to supply the consumer or other consumers. It has been found that this is extremely efficient, especially when the other consumers or the other consumer are employed for functions of the work machine that are not used to drive the work machine. In another mode, it is then conceivable that a respective driving axis is supplied via a respective hydraulic machine, wherein at least one of the hydraulic machines is then used to supply the one further consumer or at least a part of the further consumer. If necessary, the other hydraulic machine can also be used to supply the other part of the further consumers. Thus, if necessary, either a hydraulic machine for both driving axes or a respective hydraulic machine for a respective driving axis can be used extremely flexibly. The use of a hydraulic machine for both driving axes is extremely advantageous when driving straight ahead of the construction machine.

The consumer or the other consumers in addition to the driving axles can / can be: boom, spoon, slewing, handle, in particular an excavator.

In another mode can be provided that one of the hydraulic machines can be used for a single consumer, which is then in particular an attachment. The other hydraulic machine can then be provided for the further consumer or the other consumers. This is advantageous because some special attachments may require a hydraulic machine to be reserved when activating the attachment. This can be advantageous, in particular for energy reasons, when the attachment requires a certain stable pressure level.

The mode or modes may be automatically selected and / or activated by an operator.

list of figures

• 1 in einem hydraulischen Schaltplan eine Ventilblockanordnung gemäß einem Ausführungsbeispiel,
• 2 in einer schematischen Darstellung eine Steuerelektronik der Ventilblockanordnung aus 1,
• 3 in einer schematischen Darstellung unterschiedliche Modi zum Steuern von Verbrauchern aus 1,
• 4 vereinfachte Kennlinien zur Darstellung eines weiteren Modus für die Ventilblockanordnung aus 1,
• 5 und 6 jeweils eine Tabelle zur vereinfachten Darstellung eines jeweiligen Modus für die Ventilblockanordnung aus 1.

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

• 1 in a hydraulic circuit diagram, a valve block assembly according to an embodiment,
• 2 in a schematic representation of a control electronics of the valve block assembly 1 .
• 3 in a schematic representation different modes for controlling consumers 1 .
• 4 simplified characteristics for displaying a further mode for the valve block assembly from 1 .
• 5 and 6 in each case a table for the simplified representation of a respective mode for the valve block assembly 1 ,

According to 1 is a valve block assembly 1 shown according to an embodiment. This has a first hydraulic machine in the form of a hydraulic pump, which serves as the main pump 2 is used. Furthermore, a second hydraulic machine in the form of a hydraulic pump, which serves as a summation pump 4 is used provided. On the output side of a respective pump 2 and 4 is each a pressure sensor 6 connected. Furthermore, there are three main valves 8th . 10 . 12 intended. These are arranged fluidically in parallel and in each case with two pumps 2 and 4 connected. A respective main slide 8th to 12 here in each case has a pressure port P. Between a respective pressure connection P and the main pump 2 is in each case one, in particular electrically, adjustable throttle 14 . 16 and 18 intended. Furthermore, between a respective pressure port P and the summation pump 4 also in each case one, in particular electrically, adjustable throttle 20 . 22 . 24 intended. The throttles 14 . 16 and 18 are thus fluidly parallel to the main pump 2 and the throttles 20 . 22 and 24 fluidic parallel to the summation pump 4 connected.

Furthermore, for a respective main slider 8th to 12 a tank connection T provided. These are each via a tank line 26 with a tank 28 connected. Furthermore, for a respective main slider 8th to 12 a first work connection A and a second work connection B intended. To the respective work connections A . B is each a consumer 30 . 32 and 34 connected, which are each formed as a differential cylinder with one-sided piston rod. Thus serves a respective main slide 8th to 12 for controlling a respective consumer assigned to it 30 to 34 ,

A respective main slide 8th to 12 is in its basic position a spring centered. Starting from his basic position a is a respective main slider 8th to 12 in the direction of the first switching positions b via actuators 36 . 38 actuated. Here, the pressure connection P with the work connection A and the work connection B connected to the tank connection T. Furthermore, there is a respective main slide 8th to 12 starting from his basic position a in the direction of switching positions c opposite of the switching positions b displaceable. Here is a respective pressure port P with the second work connection B and the first work connection A connected to the tank connection T. The main slider 8th to 12 are each continuously adjustable.

Fluidically between the throttles 14 . 16 and 18 and the main pump 2 branches a first bypass flow path 40 off, with the tank 28 connected is. In the bypass flow path is a continuous, in particular electrically adjustable cut valve 42 intended. A valve spool of the cut valve 42 is acted upon in the direction of its opening position with a spring force of a valve spring. In the direction of closing position is the valve slide of the cut valve 42 from an actuator, which is in particular electrically controlled, acted upon by a force. Thus, with the cut valve 42 a pressure medium connection between the output side of the main pump 2 and the tank 28 to be controlled.

Furthermore branches between the throttles 20 . 22 and 24 and the summation pump 4 another second bypass flow path 44 from. In this is also a cut valve 46 arranged to a pressure medium connection between the output side of the summation pump 4 and the tank 28 to control. The cut valve 46 is in accordance with the cut valve 42 designed.

Furthermore, in 1 schematically a control unit or an electronic control system 48 shown. This serves to control the main slide 8th to 12 , the throttles 14 to 24 , the cut valves 42 and 46 and the pumps 2 . 4 , The control electronics 48 is in the following 2 explained in more detail.

According to 2 is the control electronics 48 the valve block assembly 1 out 1 shown. This is to control a respective consumer 30 to 34 , please refer 1 , one joystick each 50 . 52 and 54 provided, each with the control electronics 48 are connected. A respective joystick 50 to 54 is in each case with a block 56 connected to the part of an adaptation module or first module 58 are. In it is a respective one of the joysticks 50 to 54 predetermined default value a1 to a3 customized. Following is a respective adjusted default value b1 to b3 from the respective block 56 output. The adaptation is based on characteristics and on the basis of a time function, such as PT1 or PT2.

The respective adjusted default value b1 to b3 is in a respective block 60 the control electronics 48 fed. The blocks 60 form a default module or second module 62 , The default values b1 to b3 are then in their respective block 60 with a characteristic in a maximum pressure p_max_1 to p_max_3 transferred. The respective maximum pressure p_max_i can increase linearly with the respective increasing adjusted default value bi up to a certain size, from which then the maximum pressure p_max_i remains constant, even if the respective adjusted default value b1 to b3 continues to rise. Thus, at the beginning of a respective deflection of a joystick 50 to 54 a respective specification for the maximum pressure p_max_i steadily increase along with the deflection. From a specific actuation path of the respective joystick 50 to 54 then the respective maximum pressure remains p_max_i constant. Furthermore, the second module 62 a respective adjusted default value b1 to b3 in a respective volume flow specification Q1 to Q3 for the respective consumer 30 to 34 , please refer 1 , implemented. These are also adjusted based on a characteristic curve. In this case, then a respective volume flow specification Q1 to Q3 with the respective adjusted default value b1 to b3 increase. Furthermore, in a respective block 60 of the second module 62 a desired load-sensing information A1 to A3 generated. A respective load-handling information A1 to A3 is also according to a characteristic of the adjusted default value b1 to b3 dependent. The larger the default value b1 to b3 is, the lower is the respective load information A1 to A3 ,

According to 2 become the adjusted default values b1 to b3 , the volume flow specifications Q1 to Q3 , the load-bearing information A1 to A3 and the maximum pressures p_max_1 to p_max_3 in a block 64 the control electronics 48 fed. This forms an actuation module or third module 66 , Furthermore, in the block 64 the over the sensors 6 out 1 tapped pump pressures p_Pmp_1 and p_Pmp_2 fed. Also, in the block 64 a speed n_engine one of the pumps 2 . 4 out 1 driving motor, which is not shown, and a torque M_engine fed to this engine. From the supplied calculation quantities and pressures and the rotational speed and the torque are the control variables or actuation signals a1 , a2 and a3 for a respective actuator 36 out 1 and b1 . b2 and b3 for a respective actuator 38 generated. Furthermore, control variables or actuating signals c1 . c2 and c3 for the throttles 14 . 16 and 18 out 1 and d1 . d2 and d3 for the throttles 20 . 22 and 24 out 1 generated. In addition, control signals x_cut_1 and x_cut_2 for the respective cut valve 42 and 46 out 1 generated as the respective throttle specification. In addition, a Pump flow rate setting Vg1 and Vg2 for a respective pump 2 . 4 out 1 generated.

According to 3 Different modes (cases) are shown, via the control electronics 48 are executable. This is a respective consumer 30 to 34 out 1 one priority level each Prio0 . Prio1 . Prio2 assigned. The consumer 34 here has the highest, first priority level Prio2 , The consumer 32 has a smaller, second priority level Prio1 and the consumer 30 an even smaller, third priority level Prio0 on. In the various modes, a minimum volume flow specification (PDemMin) is provided for the respective consumers. Furthermore, a respective consumer 30 to 34 assigned a limitation factor. For the consumer 34 is a limiting factor fac_p2 , for the consumer 32 a limiting factor fac_p1 and for the consumer 30 a limiting factor fac_p0 intended. Furthermore, for a consumer 30 to 34 in each case a volume flow specification Q1 to Q3 , see also 2 , given. This is then a desired flow rate specification Q1 to Q3 (Q_demPrio (i)). In the different modes according to 3 Then, the different limiting factors can be set, which are then multiplied by the corresponding desired volume flow specification, in which case an actual volume flow specification (Q_Prio (i)) for a respective consumer 30 . 32 . 34 what can be expressed by the following formula: Q_Prio (i) = Q_demPrio (I) * fac_p (i), where i stands for a particular consumer and 0.1 or 2 for the consumer 30 . 32 or 34 can take. Thus, this results in a resulting setpoint quantity from multiplication of the nominal quantity originally required by the driver with the corresponding limitation factor. According to 3 is in a mode (Case 1 ) provided that the limitation factors are each 1, which the consumers 30 to 34 in each case the desired flow rate specification is assigned, if this is possible.

In another mode (Case 2 ) are the limiting factors for consumers 32 and 34 1 , whereby they are assigned the desired flow rate specification. For the consumer 30 a limitation factor smaller than 1 is provided, which can also result from the following formula:
fac_p0 = (P_avail - P_Prio1 - P_Prio2) / P_Prio0 where P_avail is the available power of the pumps 2 . 4 . P_Prio1 for the required power of the consumer 32 . P_Prio2 for the required power of the consumer 34 and P - Prio0 for the required power of the consumer 30 stands. Thus, in the second mode for the consumer 30 only a smaller proportion of the desired flow rate specification is provided for this, with which the limitation factor is less than 1. The flow rate specification for the consumer 30 is preferably greater than the minimum volume flow specification (PDemMin).

In another mode, unlike the mode (Case 2 ) provided that the limitation factor for the second consumer 32 0 is, with which only the first consumer 30 and the third consumer 34 are in use.

In another mode (Case 3 ) is for the consumer 34 as a limitation factor 1 intended. The limiting factor for the consumer 30 is less than 1 and can be derived from the following formula: fac_p0 = P_Prio0Min / P_prio0, where P_Prio0Min is a minimum for the consumer 30 provided volume flow specification is and P_Prio0 the desired flow rate specification for the consumer 30 , The limiting factor for the consumer 32 is less than 1 and can then result from the following formula: $$\text{fac\_p1}=\left(\text{P\_avail}-\text{P\_Prio2}-\text{P\_Prio0Min}\right)/\text{P\_Prio1},$$

In another mode (Case 4 ) can be provided that the limiting factor for the consumer 34 1 is. The consumers 30 and 32 may have a same limiting factor and / or a limitation factor of less than 1, which may result from the following formula:
fac_p0 = fac_p1 = (P_avail - P_Prio2 ) / ( P_Prio0 + P_Prio1 ). The flow rate specification for the consumer 30 can then correspond to the minimum flow rate specification (PDemMin), while the flow rate specification for the consumer 32 above the minimum volume flow specification (PDemMin).

In another mode (Case 5 ) are the limiting factors for consumers 30 and 32 0 and the limiting factor for the third consumer is less than 1 and may be given by the formula:
fac_p2 = P_avail / P_Prio2 , The supply quantity of the consumer 34 with the highest priority is thus reduced only if all other consumers have already been completely reduced. The flow rate specification for a respective consumer 30 . 32 can be below the minimum volume flow specification (PDemMin).

In 4 four diagrams are shown. The two left show an old solution and the two right a solution of the invention. The upper diagrams each show the ordinates available standing power for the pumps 2 . 4 out 1 (P_wr) and on its abscissa a time. The bottom diagrams show a volumetric flow Q on the ordinate and a time (time) on the abscissa. According to the upper left diagram, an available power for the pumps 2 . 4 out 1 (P_wr_avail) first increase linearly and then take a constant value. The required power (P_wr_demand) is initially below the available power and should then correspond to the available power in the further course of time. Thus, the required power is limited by the available power. This then leads according to the in 4 Lower left diagram that a required volume flow (Q_demHauptPmp) of the main pump 2 and a required volume flow (Q_dem SumPmp) of the summation pump 4 can not be provided because the available power (P_wr_avail) is insufficient. So far it was like that both pumps 2 . 4 have been swung back in such a case. Both the main pump 2 as well as the summation pump 4 in each case promote a lower volume flow (Q_limHauptPmp, Q_limSumPmp) and are in particular not fully swung. According to the invention then according to the in 4 right upper diagram a corresponding initial situation regarding the services available. On the other hand, according to the in 4 bottom right chart uses the available power to the main pump 2 full use, with what about the main pump 2 the required volume flow (Q_demHauptPmp) is eligible. In contrast, then the summation pump 4 in comparison to the previous solution significantly further swung back and promotes a correspondingly lower flow. This is extremely advantageous because a pump in the swung or fully swung out state is much more efficient. Thus, according to the new solution, at least one pump is used efficiently, whereas in the old solution both pumps are used inefficiently.

According to 5 Two further modes are shown. In a mode "driving not active" becomes the main pump 2 (Pmp1) for the left chain drive (left chain) of a tracked vehicle and the summation pump 4 (Pmp2) for a right chain drive (right chain) used. Furthermore, the main pump 2 for a slewing and a stem of the valve block assembly 1 used construction machine. The summation pump 4 is also used for a boom and a spoon. In contrast, the summation pump is provided in another mode (driving active) 4 to provide for both chain drives while the main pump 2 then used for the boom, the bucket, the slewing gear and the handle.

According to 6 Two further modes are shown. In the other mode (attachment not active) the main pump is again used for the left chain drive and the summation pump for the right chain drive. Besides, the main pump is 2 for the slewing and the stem, while the summation pump is used for the boom and the spoon. The use of an attachment is not intended in this mode. If an attachment is now used, it is switched to another mode (attachment active). Here then is the main pump 2 used alone for the attachment, while the summation pump 4 intended for the other consumers.

Disclosed is a valve block assembly with a valve block having at least two main spool, which are each used to control a consumer. A respective main slide is in this case connected to two, in particular electrically, adjustable hydraulic machines.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been 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 102012218428 A1 [0003]

Claims (15)

Valve block assembly comprising a valve block having at least two main spools (8, 10, 12), each for controlling a hydraulic consumer (30, 32, 34) are provided, wherein a respective main spool (8, 10, 12), a pressure port (P ) and at least one working port (A, B) is associated, and wherein two hydraulic machines with adjustable flow rate (2, 4) are provided, which are each connected to a respective pressure port (P). Valve block arrangement according to Claim 1 , wherein at least a part of the main slide fluidly between the pressure port (P) and one of the connected hydraulic machine (2, 4) is associated with a throttle (14, 16, 18). Valve block arrangement according to Claim 2 , wherein at least a part of the main slide fluidly between the pressure port (P) and the corresponding other hydraulic machine (2, 4) is associated with a throttle (20, 22, 24). Valve block arrangement according to one of the preceding claims, wherein fluidically between the pressure ports (P) and a hydraulic machine (2) branches off a bypass flow path (40) which is connectable via an adjustable cut valve (42) with a tank (28) and can be throttled over this, and / or fluidly between the pressure ports (P) and the other hydraulic machine (4) branches off a bypass flow path (44), which via an adjustable cut valve (46) with the tank (28) is connectable and about this is throttleable. Valve block arrangement according to one of the preceding claims, wherein, depending on the consumer, one hydraulic machine serves as main pump (2) and the further hydraulic machine as summation pump (4). Valve block arrangement according to one of the preceding claims, wherein an electronic control unit (48) is provided which has an adaptation module (58) in which for a respective consumer (30, 32, 34) via an input device (50, 52, 54) a default value ( a1, a2, a3) can be entered. Wherein a respective default value (a1, a2, a3) is changed via the adaptation module (58) in a respective adjusted default value (b1, b2, b3), and / or wherein one or the control electronics (48) has a default module (62), to the respective or a respective default value (a1, a2, a3) in a volume flow specification (Q1, Q2, Q3) for the corresponding consumer (30, 32, 34) and / or in a load sensing information (A1, A2, A3) for the corresponding consumer (30, 32, 34) and / or in a maximum pressure (p_max_1, P_max_2, p_max_3) implement. Valve block arrangement according to Claim 6 wherein the control electronics (48) comprises an actuation module (66) which generates an actuation signal or actuation signals based on the converted specifications, wherein as actuating signal (e) a Pumpenvolumenstromvorgabe (Vg1, Vg2) for the main pump (2) and a pump volume flow specification for the Summing pump (4) and / or an overall throttle specification (x_cut_1, x_cut_2) for the cut valve (42, 46) or for a respective cut valve (42, 46) and / or a respective control variable (ai, bi) for a respective Main slide and / or a respective control variable (ci, di) for a respective throttle (14 to 24) is provided / are. A method for controlling a valve block assembly (1) according to one of the preceding claims, wherein by hydromachines (2, 4) deliverable supply flow rates for the consumer (30, 32, 34) individually by controlling the hydromachines with adjustable flow rate (2, 4) and by control the adjustable main slide (8, 10, 12) and / or by controlling the at least one cut valve (42, 46) the connected consumers (30, 32, 34) are assignable. Method according to Claim 8 , wherein the individual assignment of the deliverable supply volume flows for the consumers (30, 32, 34) additionally by controlling the adjustable throttles (14 to 24) takes place. Method according to Claim 8 or 9 , wherein a priority level is assigned to a respective consumer (30 to 34), wherein the allocation of the supply volume flows to the consumers (30, 32, 34) takes place in dependence on the priority levels. Method according to Claim 10 wherein at least three consumers, the first consumer (34) has the highest priority level, the second consumer (32) a smaller priority level and the third consumer (30) has an even lower priority level. Method according to one of Claims 8 to 11 , wherein a respective volume flow specification (Q1 to Q3) for a respective consumer (30, 32, 34) can be predetermined, wherein a respective volume flow specification (Q1 to Q3) is assigned a respective limitation factor (fac_pi), via which a respective volume flow specification (Q1 to Q3) is reduced as required in a predetermined manner. Method according to Claim 12 in that the control electronics (48) provide one mode or several different modes in which predetermined limiting factors (fac_pi) are provided for the consumers (30, 32, 34). Method according to Claim 13 wherein the mode or modes are automatically selected and / or activated by an operator. Method according to one of Claims 8 to 14 , wherein it is provided that the one hydraulic machine (4) is used when the supply volumetric flow that can be conveyed by the other hydraulic machine (2) is no longer sufficient to cover the volume flow specification (s) of the consumer (s) (30, 32, 34).

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