EP3770428A1 - Hydraulic compressed medium supply assembly for a mobile working machine and method - Google Patents

Abstract

A hydraulic pressure medium supply arrangement is disclosed which has an adjustable axial piston machine, an actuating cylinder being controlled via a pilot valve. The pilot valve is activated by a control device. The control device has an actual pressure and / or an actual pivot angle of the adjustable axial piston machine as input variables. One or more of the input variables mentioned are compared with a suitable setpoint and a manipulated variable or a manipulated variable are output. The regulation of the input variables mentioned is part of a first control loop. A subordinate second control loop has an input variable based on the manipulated variable or variables, which serves as the setpoint. Another input variable of the second control loop is an actual delivery volume adjustment speed of the axial piston machine. A control value for the pilot valve is then provided as the output variable for the second control loop.

Description

Field of invention

The invention relates to a hydraulic pressure medium supply arrangement for an open hydraulic circuit, for example for mobile work machines, according to the preamble of claim 1.

Background of the invention

A pressure and flow rate control system is known from the document RE 30630 / 04.13 from Rexroth. This is used for the electrohydraulic control of a swivel angle, a pressure and a power of an axial piston variable displacement pump. The control system has an axial piston variable displacement pump with an electrically controlled proportional valve. An actuating piston can be controlled via this. This is used to adjust a swash plate of the variable displacement pump. A displacement transducer is provided for the actuating piston, via which a swivel angle of the swash plate can be determined on the basis of the displacement path of the actuating piston. As an alternative to the position transducer, a swivel angle of the swash plate on the swivel axis can also be tapped using a Hall sensor. The volume flow of the variable displacement pump can in turn be determined from the swivel angle of the swashplate. The variable displacement pump is driven by a motor. If the variable displacement pump is not driven and the actuating system is depressurized, the variable displacement pump swivels to a maximum delivery volume by the force of a spring. When the variable displacement pump is driven and the pilot valve is de-energized and the pump outlet is closed, the variable displacement pump swivels to a zero stroke pressure. An equilibrium between the pump pressure on the setting piston and the spring force of the spring is established at around 4 to 8 bar. The basic setting is usually taken when the control electronics are de-energized. A control for the pilot valve has a setpoint pressure, a setpoint swivel angle and optionally a setpoint power value as input variable. An actual pressure on the output side of the variable displacement pump is recorded by a pressure sensor. As explained above, an actual swivel angle is determined via the displacement transducer. The recorded actual values are digitally processed in an electronic unit and compared with the specified target values. A minimum value generator then ensures that only the controller assigned to the desired operating point is automatically active. An output signal from the minimum value generator is then a setpoint value for a proportional magnet on the pilot valve. In order to control the pilot valve, a displacement path of a valve slide of the pilot valve is recorded via a displacement sensor and reported to the controller. The document RD 30242 / 03.10 from Rexroth discloses external control electronics for the described adjustment of the axial piston adjusting machine. Furthermore, in the document RD 92 088 / 08.04 from Rexroth, an electro-hydraulic control system is disclosed.

From the EP 1 460 505 A2 alternating regulation of a pressure and a delivery flow is disclosed. In this case, a pivotable hydraulic axial piston adjusting machine is provided, which is connected to another hydraulic machine via a drive shaft. Furthermore, a control loop for a drive torque of the adjusting machine is provided. An actual drive torque and a setpoint drive torque are fed to the control loop, from which a manipulated variable for an adjusting device of the variable displacement machine is determined. The target drive torque, in turn, is an output variable of a minimum value generator. This selects an output variable for a pressure control and a volume flow control. The volume flow of the hydraulic machine connected to the adjusting machine is provided as the actual volume flow. Furthermore, a high pressure of this hydraulic machine is provided as the actual pressure.

Furthermore is in the documents EP 2 851 565 B1 , U.S. 4,801,247 , U.S. 5,182,908 , EP 034 9092 B1 , US 5267441 , US 5967756 and US 5170625 each discloses a hydraulic machine with a swivel angle sensor and a pressure sensor. The pressure, the volume flow and the power can be controlled.

Disclosure of the invention

In contrast, the invention is based on the object of creating a hydraulic pressure medium supply arrangement which is designed to be simple and inexpensive in terms of device technology and which nevertheless reliably and dynamically regulates and / or limits essential control variables of an adjustable hydraulic machine and parameters. Furthermore, a simple method should be provided for the pressure medium supply arrangement.

The object with regard to the pressure medium supply arrangement is achieved according to the features of claim 1 and with regard to the method according to the features of claim 13.

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

According to the invention, a hydraulic pressure medium supply arrangement for an open hydraulic circuit, in particular for a mobile work machine, is provided. The pressure medium supply arrangement can have a hydraulic machine and an adjusting mechanism. The adjustment mechanism is preferably used to adjust a delivery volume of the hydraulic machine. For this purpose, an adjusting cylinder with an adjusting piston is provided. Furthermore, the adjustment mechanism has an electrically proportionally controllable pilot valve. This can be used to control an inflow and / or an outflow in a control chamber of the actuating cylinder that is delimited by the actuating piston, in order to apply pressure medium to the actuating piston for actuation. Furthermore, the pressure medium supply arrangement preferably has an electronic control. This further preferably has at least one setpoint output pressure of the hydraulic machine as input variables. Alternatively or in addition, a setpoint delivery volume of the hydraulic machine can be provided as an input variable for the control. It is conceivable to set the target size (s) or, alternatively, to make them adjustable, so that they can be adapted as required during operation, for example. A manipulated variable for the pilot valve is preferably provided as the output variable of the controller. Furthermore, the controller can have a first control loop for an actual output pressure of the hydraulic machine. This is preferably tapped between a high pressure connection of the hydraulic machine and a main control valve for consumers. Alternatively or additionally, the first control circuit can be provided for an actual delivery volume of the hydraulic machine. If the hydraulic machine is an axial piston machine with an adjustable swivel cradle or swash plate for setting a delivery volume, for example the actual delivery volume can be recorded using an appropriate means, for example a swivel angle sensor such as a displacement transducer for the actuating piston. As an alternative to the position transducer, a swivel angle of the swash plate on the swivel axis can also be tapped using a Hall sensor. In other words, a measuring device is provided for detecting the displacement position or the displacement volume. It would also be conceivable to determine the pivot angle via a torque of the drive shaft and pressure measurement. Preferably, the first control circuit is subordinate to a second control circuit which can be provided for a delivery volume adjustment speed. An actual delivery volume adjustment speed, in particular as a derivative of the actual delivery volume, of the hydraulic machine is preferably provided as an input variable for the second control loop. If the actual delivery volume adjustment speed is determined via the actual delivery volume, the recorded actual delivery volume can advantageously be used for both the first and the second control loop, so that separate detection of the actual delivery volume adjustment speed is not necessary. An output variable of the second control loop is preferably the manipulated variable for the pilot valve. A manipulated variable from the first can advantageously be sent to the second control loop Control loop in the form of a delivery volume adjustment speed. The manipulated variable from the first control loop can then be a setpoint variable for the second control loop.

This solution has the advantage that an electronically controllable hydraulic machine is created for mobile applications in an open circuit, which has a simple pump adjustment mechanism without a hydro-mechanical feedback. In contrast to the prior art, it is not necessary to detect a position of the actuating piston of the pilot valve, which means that corresponding means can be dispensed with, which reduces costs and the complexity of the device. The pressure medium supply arrangement is therefore extremely simple and inexpensive. By taking into account the actual delivery volume adjustment speed, the dynamics of the system are in turn taken into account when controlling the pilot valve. The manipulated variable of the pilot valve is therefore also dependent on the delivery volume adjustment speed, which leads to a high control quality.

In a further embodiment of the invention, the first control loop preferably has the actual output pressure of the hydraulic machine and / or the actual delivery volume of the hydraulic machine as input variables.

The first control loop of the control can also be designed for an actual torque of the hydraulic machine. A setpoint torque and an actual torque, for example, are then provided as input variables for the control. As an alternative or in addition, it is conceivable that the first control loop of the controller is designed for an actual power, including an actual speed of the hydraulic machine. It is also conceivable that the actual power or the actual torque can be determined from the actual speed via a characteristic curve in order to then regulate the actual power. A regulator, in particular a P regulator, can be provided to regulate the actual torque. Alternatively, it is conceivable to design the controller as a PI controller or as a PID controller.

In a further embodiment of the invention, the first control loop has a control variable for the actual output pressure of the hydraulic machine and / or for the actual delivery volume of the hydraulic machine and / or for the actual torque of the hydraulic machine. The control can then provide a replacing regulation that has a minimum value generator for the output manipulated variables of the first control loop. An output variable of the minimum value generator is then preferably the manipulated variable in the form of the delivery volume adjustment speed, which is fed to the second control loop. The minimum value generator ensures that only the controller assigned to the desired operating point is automatically active. For example, the minimum value generator selects the smallest of the supplied manipulated variables and then feeds this to the subordinate second control loop as the setpoint delivery volume adjustment speed.

The first control circuit preferably has a controller for the delivery volume or the pivot angle - from which the delivery volume can be determined - of the hydraulic machine. This is, for example, preferably a P controller. Alternatively, it can be designed as a PI controller or as a PID controller. The controller can have a setpoint swivel angle and an actual swivel angle or a setpoint delivery volume or actual delivery volume as an input variable.

A filter, for example in the form of a PT1 element or a higher-order filter, is preferably provided for the actual swivel angle. The filter can be used to smooth the signal in a simple manner.

The first control loop preferably has a controller for the actual output pressure of the hydraulic machine. The actual output pressure, in particular detected by a pressure sensor, and the setpoint output pressure are supplied to it as input variables. A PID controller is preferably provided as the controller. Alternatively, a P controller or PI controller can be used. The target output pressure of the hydraulic machine is preferably adjustable. In particular, to determine the setpoint output pressure, an actual load sensing (LS) pressure of the consumers that are supplied with pressure medium via the pressure medium supply arrangement is recorded. In particular, the actual LS pressure is the highest actual load pressure of the consumer. The actual LS pressure is preferably fed to the control or the regulator for the actual output pressure as an input variable. With a load sensing (LS) control, the highest load pressure of the variable displacement pump should be reported and the variable displacement pump should be regulated in such a way that the actual output pressure in the pump line is a certain pressure difference (delta_p) above the highest actual load pressure. It is thus advantageously provided that the controller for the actual output pressure is additionally supplied with a setpoint differential pressure as an input variable. The target output pressure can then be calculated by adding the actual LS pressure and the target differential pressure and serve as an input variable for the controller. The target differential pressure can either be permanently parameterized or flexibly adjustable and specified as a parameter.

In particular, it is also conceivable to record several actual LS pressures and to establish a maximum value or to prioritize in the control. This can be done by feedback to a main valve or to a main control valve if, for example, a delivery rate of the hydraulic machine (pump) is limited and thus the delivery rate guided through the main valve can be limited, whereby, for example, a prioritization of a hydraulic steering in the event of a Undersupply is made possible. In addition to the LS pressure control, the hydraulic machine (pump) is advantageously set to a minimum amount in order to also ensure steering ability in the event of pressure sensor misinformation. In other words, the LS pressure, on the basis of which the hydraulic machine is regulated, can be regarded as the leading variable. In addition, it is conceivable that a minimum amount is set as a function of the steering request, so that the steering ability is maintained even in the event of incorrect information regarding the LS pressure.

In the case of a controller for the actual output pressure and / or for the actual delivery volume and / or for the actual torque, an I component can be provided, such as, for example, with a PID controller, which is explained above. It can then be provided, particularly when using the minimum value generator, that the I component is frozen or, in particular partially or completely, reset for the controller or controllers that are not active and have an I component. If the controller is then active, the I component is used in the usual way and the controller can react immediately. This means that the I component of the controller (s) is not used when inactive. This refinement can be referred to as "anti-windup", which means that freezing and resetting of the I component are combined.

One or more filters with a pressure-dependent filter coefficient can advantageously be provided for the regulator of the actual output pressure. The respective filter is, for example, a variable PT1 filter or a higher-order filter. The filter or a respective filter is preferably provided for the actual output pressure and / or for the actual LS pressure. The pressure-dependent filter is preferably designed in such a way that the filtering is reduced when the actual output pressure of the hydraulic machine increases and, conversely, when the actual output pressure of the hydraulic machine decreases, the filtering is increased in order to influence the dynamics of the control.

Alternatively or additionally, one or more filters, in particular with pressure-dependent filter coefficients, can be used for the other controllers listed above and below, in particular for one or more input variables.

Alternatively or additionally, it is conceivable to provide an asymmetrical filter for the controller of the actual output pressure and / or for one or more of the controllers listed above and below, in particular for the one or more input variable (s). This depends on the direction in which the swash plate is pivoted. That is, the filtering of the filter in the first pivoting direction is different from the filtering in the second pivoting direction.

In a further embodiment of the invention, a gain factor (Kp), in particular for the controller for the actual output pressure, is provided, which depends on the actual temperature of the pressure medium Hydromachine, in particular the output-side pressure medium, and / or the actual speed of the hydromachine and / or the actual output pressure of the hydromachine and / or a predetermined pressure gradient or setpoint pressure gradient, in particular for the setpoint output pressure of the hydromachine. The gain factor can thus be determined as a function of these variables. The gain factor can then be multiplied by the control deviation, for example, with the controller, the control deviation being, for example, the set differential pressure minus the actual differential pressure and the actual differential pressure being equal to the actual LS pressure minus the actual output pressure. It is preferably provided that the lower the actual temperature, the lower the gain factor, since this can prevent or at least reduce oscillation of the hydraulic machine, preferably when the hydraulic machine is cold. Correspondingly, conversely, the higher the actual temperature, the higher the gain factor. Alternatively or additionally, it can be provided that the lower the actual speed of the hydraulic machine, the greater the gain factor, since the pressure build-up depends on the volume flow and thus on the speed of the hydraulic machine. Correspondingly, conversely, the higher the actual speed, the smaller the gain factor. Alternatively or additionally, it can be provided that the greater the pressure gradient of the target output pressure, the greater the gain factor. This is advantageous because the greater the pressure gradient, the greater the requirement for swiveling out the hydraulic machine and thus the hydraulic machine must react more quickly than in the small-signal range. Conversely, it then also applies here that the smaller the pressure gradient, the smaller the gain factor. Alternatively or additionally, it can be provided that the greater the actual outlet pressure, the greater the gain factor. This is advantageous because the higher the actual outlet pressure, the higher the system dynamics. The hydraulic machine can thus be swiveled more quickly without becoming unstable. The reverse is also true.

The gain factor can advantageously be designed as an operating point-dependent control parameter. For the pressure control and / or for the torque control and / or for the swivel angle control, the following can apply, for example: the greater the actual output pressure, the greater the gain factor can be or the gain factor is increased up to a predetermined actual output pressure and then as it continues to rise Actual outlet pressure reduced again. In other words, a gain factor can also be provided in the regulators for the actual output pressure and / or for the actual torque, in particular for the actual variables. In particular, in other words, a pressure-dependent adaptation of the control loop gains can be provided. The control parameters can thus be adapted during operation of the pressure medium supply arrangement. There is advantageously a need-based adaptation of the control dynamics and / or control stability during operation.

In a further embodiment of the invention it can be provided that a setpoint pressure gradient is provided for the regulator of the actual output pressure. This is preferably adaptable and adjustable. The target pressure gradient can then, for example, have an influence on the target output pressure. One influence is, for example, such that the higher the setpoint pressure gradient, the faster the hydraulic machine should swivel out. The higher the target pressure gradient, the faster the requirement grows than the actual gradient, which is why the hydraulic machine is pivoted faster in order to achieve the target pressure gradient. It is conceivable to use the target pressure gradient as a limitation for the target output pressure or as a limitation for changing the target output pressure.

In a further embodiment of the invention, the first control loop preferably has a controller for the actual torque or the actual power on the basis of the actual torque multiplied by the actual speed. An actual speed can be provided as the input variable, which is picked up by a drive shaft, in particular via a speed sensor, of the hydraulic machine. The actual torque or the absorption torque of the hydraulic machine (pump) can then be calculated from the actual speed. The actual torque is calculated from the actual swivel angle multiplied by the actual output pressure divided by the hydromechanical efficiency. The hydromechanical efficiency is a function of the actual output pressure, the actual swivel angle and the actual speed and can be determined, for example, via a characteristic curve. Furthermore, a setpoint torque can be specified for the controller. The output-side manipulated variable of the controller is preferably fed to the minimum value generator. The characteristic curve for determining the actual torque is dependent, for example, on the actual pressure and / or on the actual swivel angle. In other words, an instantaneous power can be calculated with the controller, in particular if the actual speed is included.

In a further embodiment of the invention, the actual variables for the first and second control loops or a part of the actual variables and one or more derivatives thereof are filtered to calm the signals. As already explained above, a PT1 element or a variable PT1 element are used here, for example.

In a further embodiment of the invention, it is conceivable to provide a delivery volume adjustment speed specification or a maximum delivery volume adjustment speed for the control, which is fed to the second control loop, in particular downstream of the minimum value generator. In particular, the delivery volume adjustment speed specification is fed to the control via a regulating element. This preferably has the manipulated variable from the first control loop as an input variable, that is to say the manipulated variable output by the minimum value generator. The delivery volume adjustment speed specification can be provided as a further input variable be. The final setpoint delivery volume adjustment speed for the second control loop can then be provided as the output variable of the control element. In particular, the control value of the minimum value generator is limited via the additionally specified delivery volume adjustment speed specification, which can be adjusted, for example, in order to influence the control dynamics of the pressure medium supply arrangement. The delivery volume adjustment speed specification can be, for example, a positive or negative maximum of the delivery volume adjustment speed. The higher the final target delivery volume adjustment speed, the faster the hydraulic machine can swing out.

With the adjustable setpoint pressure gradient explained above and / or the adjustable delivery volume adjustment speed specification, the control dynamics of the pressure medium supply arrangement can be influenced in a simple manner. Thus, the control force for the pilot valve can be dependent on the setpoint pressure gradient and / or on the delivery volume adjustment speed specification. These values can be variably adjusted during operation. The control dynamics can thus be adapted as required during operation and, for example, be dependent on the operating point or operating point. The value (s) can thus be used to limit and / or adapt the pump dynamics. The swivel angle of the hydraulic machine and / or the delivery volume adjustment speed can then be adjusted in such a way that the desired value or the desired values are not exceeded. In other words, with the adjustable variables (target pressure gradient and / or the adjustable delivery volume adjustment speed specification), the dynamics of the pressure medium supply arrangement can be adjusted via software parameters, with which, for example, a soft or hard machine behavior can be set. The dynamics can also be changed for partial functions. One sub-function can be adapted with the set pressure gradient and the other sub-function with the delivery volume adjustment speed specification. By adapting the dynamics, it is also possible to reduce vibrations. Furthermore, jerky movements can be avoided. It has been shown that the hydraulic pressure medium supply arrangement leads to an increase in efficiency, in particular due to less control oil consumption.

Another advantage of the hydraulic pressure medium supply arrangement is easier integration compared to the hydromechanical controller, since, for example, connecting lines or hoses to the hydromechanical controller of the variable displacement pump are omitted.

In a further embodiment of the invention, a pilot control and / or an auto-calibration of a neutral current can be provided for an actuator of the pilot valve. In other words, there can be a pressure-dependent specification of a neutral signal value for the pilot valve. The neutral signal value is, for example, the full control value for the Pilot valve in which the delivery volume adjustment speed is zero. The actual outlet pressure can be used for this. A neutral current can then be determined from this, in particular via a characteristic map. This is then preferably fed to the manipulated variable of the control, in particular by addition. The control can be relieved by the pre-control of the neutral current. In other words, the neutral current can be auto-calibrated. This may be necessary to maintain a steady state of the hydraulic machine depending on an actual output pressure and / or a viscosity of the pressure medium and / or a spring spread and / or a magnetic spread of the pilot valve. This enables the hardware spread to be compensated for using the auto-calibration of the neutral current.

A target torque gradient is advantageously provided for the controller of the actual torque. This can for example be designed to be adaptable and adjustable. The target torque gradient can, for example, have an influence on the target torque. In this case, the setpoint torque gradient is preferably provided as a limit for the setpoint torque or for the limitation of the change in the setpoint torque. It is also conceivable to regulate the target torque gradient as a default. In this case, a target torque can be formed based on the target torque gradient. A filter or prefilter provided can then set a target dynamic.

In a further embodiment, a higher-level machine control can be provided in addition to the control or pump control. This is for example the actual output pressure and / or the actual swivel angle and / or the actual torque and / or the actual delivery volume and / or the actual delivery volume adjustment speed and / or the gradient of the actual output pressure and / or the Maximum torque and / or the gradient of the change in torque supplied.

In a further embodiment of the invention it can be provided that a valve slide of the pilot valve is activated in such a way that it executes an axial oscillating movement temporarily or continuously, in particular when the pressure medium supply arrangement is in operation. The oscillating movement is preferably carried out in such a way that the current switching position of the valve slide is practically not influenced. In other words, there is a pressure-dependent adaptation and optimization of the hysteresis-reducing measure (dither) with the aim of optimizing the hysteresis of the pilot valve and not influencing the control dynamics by countercompensation by the dither, especially if the controller output works in phase opposition or in phase with the dither.

In other words, a method is disclosed that is provided for regulating a stroke volume and / or a torque and / or a pressure of a hydrostatic machine.

• Erfassen eines vorgegebenen Soll-Drehmoments,
• Erfassen eines vorgegebenen Soll-Hubvolumens,
• Erfassen eines vorgegebenen Soll-Drucks,
• Erfassen eines Ist-Hubvolumens oder eingestelltem Hubvolumens,
• Erfassen eines Ist-Drucks oder eingestelltem Drucks,
• Ermittlung des Ist-Drehmoments oder des eingestellten Drehmoments an der Triebwelle der Maschine.

This can have an adjusting device for adjusting its stroke volume. The method preferably has the following steps:

• Acquisition of a specified target torque,
• Acquisition of a specified target stroke volume,
• Acquisition of a specified target pressure,
• Acquisition of an actual stroke volume or a set stroke volume,
• Acquisition of an actual pressure or a set pressure,
• Determination of the actual torque or the set torque on the drive shaft of the machine.

As a further step, regulating a volume flow into or out of the adjusting device by means of a control valve for adjusting the stroke volume based on a force difference between a control force and a force acting on the control valve in the opposite direction can be provided. The force acting on the control valve in the opposite direction to the control force can be a spring force. The control force can furthermore be an electrical force of an electromagnetic valve. The machine is set as a function of the recorded stroke volume and / or pressure and / or target stroke volume and / or target pressure and / or target torque. The stroke volume is preferably set so that the smallest stroke volume is always set, which leads to one of the target values being reached.

The hydraulic machine is preferably de-energized with zero stroke or with maximum stroke, depending on the fail-operation application.

As explained in the introduction, the volume flow of the hydraulic machine or variable displacement pump can be determined from the swivel angle of the swash plate. If the variable displacement pump is not driven and the actuating system is depressurized, the variable displacement pump swivels to a maximum delivery volume, for example, by a spring force of a spring. When the variable displacement pump is driven and the pilot valve is de-energized and the pump outlet is closed, the variable displacement pump swivels to a zero stroke pressure. A balance between the pump pressure on the setting piston and the spring force of the spring plus the pump pressure on the opposing piston is established at around 4 to 8 bar. The basic setting is usually taken when the control electronics are de-energized. Conversely, it would also be conceivable that when the pilot valve is de-energized, the variable displacement pump is swiveled to the maximum delivery volume in order to ensure a pressure medium supply to a consumer such as a steering system. A pressure limiting valve is then preferably provided in order to limit the actual output pressure of the hydraulic machine. This can be done, for example, by the valve behavior of the pilot valve is inverted. For example, when the pilot valve is de-energized, the actuating cylinder connection can be connected to the tank connection.

Brief description of the drawings

• Fig. 1 in einer schematischen Darstellung eine hydraulische Druckmittelversorgungsanordnung gemäß einem ersten Ausführungsbeispiel,
• Fig. 2 in einer schematischen Darstellung eine Steuerung für die Druckmittelversorgungsanordnung aus Fig. 1,
• Fig. 3 in einer schematischen Darstellung eine Steuerung für die Druckmittelversorgungsanordnung aus Fig. 1 gemäß einem weiteren Ausführungsbeispiel,
• Fig. 4 und Fig. 5 jeweils in einer schematischen Darstellung eine Ermittlung von Verstärkungsfaktoren eines Reglers gemäß einem Ausführungsbeispiel,
• Fig. 6a und 6b eine Raupenbagger und in einer schematischen Darstellung eine Druckmittelversorgungsanordnung für einen Raupenbagger,
• Fig. 7a und 7b einen Teleskoplader und in einer schematischen Darstellung eine Druckmittelversorgungsanordnung für einen Teleskoplader,
• Fig. 8a und 8b einen Kompaktbagger und in einer schematischen Darstellung eine Druckmittelversorgungsanordnung für einen Kompaktbagger und
• Fig. 9a und 9b ein Kühler-Lüfter-System und in einer schematischen Darstellung eine Druckmittelversorgungsanordnung für ein Kühler-Lüfter-System.

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

• Fig. 1 in a schematic representation a hydraulic pressure medium supply arrangement according to a first embodiment,
• Fig. 2 in a schematic representation of a control for the pressure medium supply arrangement Fig. 1 ,
• Fig. 3 in a schematic representation of a control for the pressure medium supply arrangement Fig. 1 according to a further embodiment,
• FIGS. 4 and 5 in each case in a schematic representation a determination of gain factors of a controller according to an embodiment,
• Figures 6a and 6b a crawler excavator and, in a schematic representation, a pressure medium supply arrangement for a crawler excavator,
• Figure 7a and 7b a telescopic loader and, in a schematic representation, a pressure medium supply arrangement for a telescopic loader,
• Figure 8a and 8b a compact excavator and, in a schematic representation, a pressure medium supply arrangement for a compact excavator and
• Figures 9a and 9b a cooler-fan system and, in a schematic representation, a pressure medium supply arrangement for a cooler-fan system.

According to Fig. 1 a hydraulic pressure medium supply arrangement 1 is shown, which has a hydraulic machine in the form of an axial piston machine 2. This has a swivel cradle for adjusting a delivery volume. The axial piston machine 2 can be used both as a pump and as a motor. The axial piston machine 2 is driven via a drive unit 4, which can be, for example, an internal combustion engine, such as a diesel unit, or an electric motor. The axial piston machine 2 is connected to the drive unit 4 via a drive shaft 6. A speed 8 of the drive shaft 6 can be tapped via means not shown, for example via a speed sensor, and fed to a control of the pressure medium supply arrangement 1. An adjusting mechanism 12 is provided for the axial piston machine 2. This has a pilot valve 14. Its valve slide can be controlled electrically proportionally via an actuator 16. For this is A manipulated variable 18 is supplied to the actuator 16 by a controller 20. The valve slide of the pilot valve 14 is acted upon by a spring force of a valve spring 22 in the direction of a basic position. The spring force acts against the actuator force of the actuator 16.

The output side of the axial piston machine 2 is connected to a pressure line 24, which in turn is connected to a main control valve 26 or valve block. This can be used to control the pressure medium supply between the axial piston machine 2 and one or more consumers. A control line 28 branches off from the pressure line 24 and is connected to a pressure connection P of the pilot valve 14. The control line 28 is formed, for example, in a housing of the axial piston machine 2. The pilot valve 14 also has a tank connection T which is connected to a tank via a tank line 30. In addition, the pilot valve 14 has a working connection A, which is connected to a control chamber 32 of an actuating cylinder 34. The control chamber 32 is delimited by an actuating piston 36 of the actuating cylinder. A swash plate of the axial piston machine 2 can then be adjusted via the adjusting piston 36. A displacement path of the actuating piston 36 is detected via a displacement transducer 38. Alternatively or additionally, a swivel angle of the swivel cradle of the axial piston machine 2 is tapped from a swivel axis of the swivel cradle via a rotary, magnetic sensor. The actual delivery volume or the actual displacement volume of the axial piston machine 2 can then be determined via the detected path. The actual delivery volume 40 is then reported to the controller 20. In the basic position of the valve slide of the pilot valve 14, the pressure connection P is connected to the working connection A and the tank connection T is blocked. When the actuator force of the actuator 16 is applied to the valve slide, the valve slide, starting from its basic position, is moved in the direction of switching positions in which the pressure connection P is blocked and the working connection A is connected to the tank connection T. Thus, in the basic position of the valve slide of the pilot valve 14, pressure medium from the pressure line 24 is applied to the actuating piston 36. Furthermore, a cylinder 42 is provided in the adjustment mechanism 12. This has an actuating piston 44 which engages the swash plate of the axial piston machine 2. The actuating piston 44 delimits a control chamber 46 which is connected to the pressure line 24. The actuating piston 44 is acted upon by pressure medium of the control chamber 46 and by the spring force of a spring 48 in such a way that it loads the swash plate in the direction of increasing the delivery volume.

Furthermore, a pressure sensor 50 is provided, via which the pressure in the pressure line 24 is tapped and reported to the controller 20, the pressure being an actual output pressure 52. In addition, a pressure sensor 54 is provided, which detects the highest actual load pressure (actual LS pressure) 56 that is transmitted to controller 20.

A controller 57 is connected to the controller 20 via a CAN interface 58 in order, in particular, to transmit the actual speed to the controller 20. It is also conceivable to feed the actual speed 8 directly to the controller 20.

When the pressure medium supply arrangement 1 is in use, the position of the swash plate of the axial piston machine 2 is controlled via the pilot valve 14 and the actuating piston 36. A conveyed volume flow of the axial piston machine 2 is proportional to the position of the swash plate. The adjusting piston 44 or counter-piston, which is pretensioned by the spring 48, is constantly subjected to the actual output pressure or pump pressure. When the axial piston machine 2 is not rotating and the adjusting mechanism 12 is depressurized, the swash plate is held in a position +100 percent by the spring 48. When the axial piston machine 2 is driven and the actuator 16 of the pilot valve 14 is de-energized, the swash plate swivels to a zero stroke pressure, since the actuating piston 36 is acted upon by pressure medium from the pressure line 24. An equilibrium between an actual output pressure at the setting piston 36 and the spring force of the spring 48 is established at a predetermined pressure or pressure range, for example between 8 to 12 bar. This zero-stroke operation is assumed, for example, in the case of de-energized electronics or control 20. The control of the pilot valve 14 takes place via the controller 20, which is, for example, preferably digital electronics, or alternatively analog electronics. The controller 20 processes the required control signals, which is explained in more detail below.

Fig. 2 shows schematically a mode of operation of the controller 20. This has a first control circuit 60 and a second control circuit 62. The first control circuit 60 has a controller 64 for a swivel angle of the swash plate of the axial piston machine 2 Fig. 1 , a regulator 66 for the output pressure of the axial piston machine 2 and a regulator 68 for a torque of the axial piston machine 2. The controller 64 has a setpoint delivery volume 70 and the actual delivery volume 40 as input variables. A manipulated variable 72 is provided as the output variable. The controller 66 has a setpoint output pressure 74 and the actual output pressure 52 as input variables. A manipulated variable 75 is provided as the output variable. The controller 68 has an actual torque 76 or a setpoint torque as input variables. The actual torque is provided as a further input variable, which in turn can be determined using a characteristic map for the actual speed 8, for example. A manipulated variable 78 is provided as the output variable for the controller 68. In the case of the respective controller 64 to 68, the input variables are each fed to a control element in the form of a PID controller.

The manipulated variables 72, 75 and 78 are fed to a minimum value generator 80. This ensures that only the controller 72, 75 or 78 is active. In this case, either the output pressure, the torque or the delivery volume is precisely regulated, the other two variables in each case being below a predetermined setpoint. An output signal of the minimum value generator 80 is then a setpoint in the form of a delivery volume adjustment speed or a set delivery volume adjustment speed 82. This is then an input variable for the second subordinate control loop 62. Another input variable of the second control loop 62 is the derivation of the actual delivery volume 40 , which is then an actual delivery volume adjustment speed 84. The input variables 82 and 84 for the second control loop 62 are then fed to a control element in the form of a PID element 86. This then outputs the manipulated variable 18 for the pilot valve 14 Fig. 1 out.

According to Fig. 3 is another embodiment for the controller 20 from Fig. 1 shown. This has a regulator 88 for the delivery volume of the axial piston machine 2, see also Fig. 1 . Furthermore, a regulator 90 for the output pressure of the axial piston machine 2 and a regulator 92 for the torque of the axial piston machine 2 are provided. This is part of a first control loop 94. In addition, a second control loop 96, which is subordinate to the first control loop, is provided for the delivery volume adjustment speed of the axial piston machine 2.

The controller 88 has a control element 98 in the form of a P element. The target delivery volume 70 and the actual delivery volume 40 are provided as input variables. The actual delivery volume 40 is supplied with the regulating element 98 via a filter in the form of a PT1 filter. On the output side of the controller 88, the manipulated variable 72 is provided as an output variable which is fed to the minimum value generator 80.

The controller 90 has the actual output pressure 52, the actual LS pressure 56, a target pressure difference 100 and a target pressure gradient 102 as input variables. The actual LS pressure 56 and the desired pressure difference 100 are linked via a summing element 104 to form a desired output pressure. The target output pressure is then fed to a control element 106 in the form of an inverted PT1 element, which estimates a probable signal profile. The target output pressure is then fed to a control element 108, which has the target pressure gradient 102 as a further input variable. The setpoint pressure gradient 102 then specifies the maximum possible gradient that should be provided. The setpoint output pressure is then influenced by the predefined setpoint pressure gradient 102 via the control element 108 in such a way that the dynamics of the pressure medium supply arrangement 1 start with the setpoint pressure gradient 102 Fig. 1 is controllable. For example, the influencing can be such that the higher the setpoint pressure gradient 102, the faster the swash plate of the axial piston machine 2 can be adjusted. Conversely, the smaller the target pressure gradient, the slower the swash plate of the axial piston machine 2 is adjusted. After the control element 108 is then the The set output pressure is fed to a control element 110 in the form of a PID element. The actual output pressure 52 is then provided as a further input variable for the control element 110. The manipulated variable 75, which is fed to the minimum value generator 80, results as the output variable of the control element 110.

The actual LS pressure 56 of the regulator 90 is fed to a filter 112, which is a variable PT1 filter, before the summing element 104. The same applies to the actual output pressure, which is also fed to a filter 114 in the form of a variable PT1 filter upstream of the control element 110. The filters 112 and 114 have variable, in particular pressure-dependent, filter coefficients, which is explained in more detail above.

The controller 92 has the actual speed 8, the actual delivery volume 40, the actual output pressure 52 and a target torque 116 as input variables. The input variables are fed to a control element 118 in the form of a P element. The manipulated variable 78, which is fed to the minimum value generator 80, is provided as the output variable for the control element 118. After the control element 118, a control element 120 is provided for the manipulated variable 78, which, like the control element 106, is an inverted PT1 filter. Furthermore, the actual speed, the actual delivery volume 40 and the actual output pressure 8 are fed to a control element 122 before being fed to the control element 118. This is used to calculate an actual torque 124 based on the actual speed 8, on the actual delivery volume 40 and the actual output pressure 8. The calculation is carried out using a map of the control element 122. The map is dependent on the actual output pressure 52 , which is fed to the control element 122. Furthermore, the actual delivery volume 40 is fed to the control element 122. The characteristic map can then alternatively or additionally depend on the actual delivery volume 40. In other words, the actual torque 124 is formed from the actual speed 8 and from the actual output pressure 52 and / or from the actual delivery volume 40. The actual torque 124 is then fed to a filter 126 in the form of a PT1 element before it reaches the regulating element 118.

Furthermore, the actual delivery volume 40 is fed to a filter 99 in the form of a PT1 element before it is fed to the regulating element 98.

The minimum value generator 80 forms the setpoint delivery volume adjustment speed 82 from the manipulated variables 72, 75 and 78. This is fed to a control element 128. The dynamics of the pressure medium supply arrangement 1 can be influenced with this. For this purpose, a delivery volume adjustment speed preset 130, which is adjustable, is provided as a further input variable for the regulating element 128. For example, with the delivery volume adjustment speed specification 130, the set delivery volume adjustment speed 82 output from the minimum value generator 80 can be limited and / or influenced in such a way that the higher the size 130, the faster the swash plate of the axial piston machine 2 can be pivoted and vice versa. The dynamics of the pressure medium supply arrangement 1 can thus be influenced by adjusting the delivery volume adjusting speed specification 130 and / or by adjusting the setpoint pressure gradient 102. For example, the pressure medium supply arrangement 1 can hereby be adapted in a simple and inexpensive manner to different work machines and / or to different conditions of use and / or to different purposes.

After the control element 128, the final setpoint delivery volume adjustment speed 132 is fed to the second control circuit 96 as an input variable. This has a control element 134 in the form of a PI element. The actual delivery volume adjustment speed 84 is provided as a further input variable for the control element 134. This is based on the actual delivery volume 40, which is derived in a control element 136. The derivation, that is to say the actual delivery volume adjustment speed, is then fed to a filter 138 in the form of a PT1 filter. A control element 140 in the form of an inverted PT1 filter is then provided before the actual variable 84 is fed to the control element 134. The control element 134 of the second control circuit 96 has the manipulated variable 18 for the pilot valve 14 as an output variable Fig. 1 on. This is fed to a summing element 142. A precontrol value 144 is provided as a further input variable for the summing element 142. This is an output variable of a control element 150, which has the actual output pressure 52 as an input variable. The pilot control value 144 is then determined on the basis of the actual output pressure 52. The summing element 142 then combines the manipulated variable 18 and the precontrol value 144, with which a neutral current of the pilot valve is precontrolled. There is thus a pressure-dependent specification of a neutral signal value for the pilot valve 14 Fig. 1 . This has the advantage that the controller 20 is relieved of this control task. A final manipulated variable 146 for the pilot valve 14 is then provided as the output variable of the summing element 142.

It is conceivable that the summing element 142 has an in Fig. 3 downstream control element, not shown, which has the manipulated variable 146 as an input variable. This is superimposed by the control element with a low-frequency signal so that the valve slide of the pilot valve 14 is constantly in an axial oscillating movement in order to prevent the valve slide from sticking. The final manipulated variable for the pilot valve 14 is then provided as the output variable of the control element. The superposition with the low-frequency signal can be referred to as "dithering". The aim of the dither is to reduce the hysteresis of the pilot valve 14 by maintaining a small movement of the valve slide. This movement must not become too large in order to avoid effects on the system (for example pilot valve 14 vibrates too violently so that the pivot angle or pressure also sees this vibration). The dither (frequency and amplitude) is optimized so that the hysteresis is minimal and the system is not is stimulated. The lower the frequency and the greater the amplitude, the easier it is to keep the valve slide in motion. A small frequency, however, leads to a long period of the superimposed "sine signal". This creates the problem that this period can run in the opposite direction to the setpoint signal. You get a delayed reaction if the superimposed dither runs in the other direction than the target signal, which can be disadvantageous in the pump control. However, there is the possibility that the dither frequency can be increased and / or the amplitude reduced at higher pressures, since better lubrication takes place due to the pressure and the hysteresis of the pilot valve 14 decreases. This also reduces the influence of an out-of-phase dither and increases the control dynamics.

Fig. 4 shows schematically an operating point-dependent control parameter for the controller 20. This is, for example, a gain factor Kp of the controller 90 for the output pressure of the axial piston machine 2. The gain factor Kp is fed to the controller 20 via the control element 110, for example. According to Fig. 4 For example, the gain factor Kp can be calculated via a control element 152 as a function of a temperature 154 of a pressure medium of the pressure medium supply arrangement 1. The temperature is tapped from the pressure medium in the pressure line 24, for example via a sensor. The gain factor Kp is then determined, for example, using a map. Alternatively or in addition, the gain factor can depend on the actual speed 8 via a control element 156. The gain factor Kp is also determined using a characteristic map. As an alternative or in addition, a control element 158 is provided, by means of which the gain factor Kp can be determined via the actual output pressure 52, and this can also take place via a characteristic map. Furthermore, as an alternative or in addition, the gain factor Kp can be determined via a control element 160 based on the setpoint pressure gradient 102. The setpoint pressure gradient 102 can be derived from the setpoint output pressure 74 via a control element 162. If the gain factor Kp is determined via a plurality of control elements 152, 156, 158, 160, it can be linked via a respective output-side control element 164 and then finally output as the output variable of the control element 164.

According to Fig. 5 can alternatively or in addition to the in Fig. 4 The control elements 152, 156, 158, 160 shown, the gain factor Kp can be determined via the actual output pressure 52. A control element 166 is provided for this, in which the gain factor Kp is then determined based on the actual output pressure 52 via a characteristic map. In this case, the greater the actual outlet pressure, the greater the gain Kp. The gain factor Kp can also be used for the controller 88 and / or 92 as an alternative or in addition to the controller 90.

It is also conceivable that a temporal adaptation of the transit times of at least one signal or part of the signals or all signals of the control loops 94 and 96 can be made Fig. 3 is provided, wherein in particular a phase position of the signal or signals can be adjusted. This can take place, for example, via the control element 106 and / or 120.

In the control element 150, the pilot control value 144 can be determined, preferably based on a model, taking into account flow forces in the pilot valve 14 and / or a magnetic characteristic of the actuator 16 and / or a control edge characteristic of the valve slide of the pilot valve 14 and / or a spring stiffness of the valve spring 22.

According to Figure 6a is shown a crawler excavator according to Figure 6b a pressure medium supply arrangement, see Fig. 1 , having. This has the axial piston machine 2, which is driven by the drive unit 4 in the form of a diesel unit. The supply of pressure medium to hydraulic cylinders 168 and 170, to hydraulic machines 172, 174 for moving the crawler excavator and to an auxiliary hydraulic drive 176 is controlled via the main control valve 26. The crawler excavator here has various input means 178 for an operator that are connected to a CAN bus 180. Furthermore, pressure sensors 182, 184 are connected to the CAN bus 180. These pick up the actual output pressure of the axial piston machine 2. A safety valve is provided on the inlet side of the hydraulic cylinders 168, 170, which safeguard the hydraulic cylinders 168, 170 in the event of a break in a feed line. As explained above, the required input variables are detected via the controller 20 and, in particular, the pilot valve 14 is controlled. In addition, the main control valve 26 is controlled as a function of the signals of the input means 178 detected via the CAN bus 180.

Figure 7a shows a telehandler with one of the pressure medium supply arrangement according to FIG Figure 7b . This has two axial piston machines 2 and 186, which are driven by the drive unit 4 in the form of a diesel unit via a common drive shaft. Pilot valves of the axial piston machine 2, 186 are controlled via the controller 20 as explained above. The axial piston machine 186 serves to supply pressure medium to a wheel brake 188, a steering system 190 and a pilot oil supply 192. The pilot oil supply 192 is provided for the main control valve 26 or the main control valve block. The pressure medium supply to hydraulic cylinders 168, 170, 194, 196 is controlled via this. Furthermore, a hydraulic machine 198 used and the auxiliary hydraulic motor 176 are controlled via the main control valve 26. According to the embodiment in Figures 6a and 6b Input means 178 are also provided here, which are connected, for example, to controller 20 via CAN bus 180. Furthermore, a communication device 200 is provided in order to carry out wireless communication with a server and / or with a computer, for example via radio or WiFi. For example, input variables for the controller 20 can then be adapted via the communication device 200 and / or software can be expanded or updated. It is also possible to send data via the communication device 200 that contain information about a state of the pressure medium supply arrangement 1.

According to Figure 8a is a compact excavator with a pressure medium supply arrangement according to Figure 8b shown. Here, the axial piston machine 2 can be seen, which is driven by the drive unit 4 in the form of a diesel unit. Furthermore, the controller 20 is shown, which is connected, for example, to a pressure sensor 202 which picks up the actual output pressure of the axial piston machine 2. In addition, the controller 20 is connected to a pressure sensor 204 which picks up the highest load pressure via the main control valve 26 or the main control block. Furthermore, the controller 20 is connected to the controller 20 with a displacement transducer 206 for the swivel angle of the swash plate of the axial piston machine 2. In addition, the pilot valve 14 is connected to the controller 20. Five hydraulic cylinders 208 are connected to the main control valve 26. Furthermore, the hydraulic machines 172, 174 and the hydraulic auxiliary motor 176 are connected. The pilot oil supply 192 can optionally be provided. Input means 178 can hydraulically control the main control valve 26, for example, or be connected to the pressure medium supply arrangement via the CAN bus 180.

According to Figures 9a and 9b the possibility of using the pressure medium supply arrangement 1 is off Fig. 1 shown for a fan system. According to Figure 9a the axial piston machine 2 is provided, which is driven via the drive unit 4, for example in the form of a diesel unit. The actual output pressure of the axial piston machine 2 is tapped via the pressure sensor 50. A fan motor in the form of a hydraulic machine 210 is driven via the axial piston machine 2. This in turn drives blades 212 to generate a flow of air. The coolant of a cooling circuit is then cooled via the air flow. The pilot valve 14 can be controlled via the controller 20. One or more temperatures picked up by sensors can be fed to controller 20, for example, via CAN bus 180. The temperature can, for example, be a temperature of the coolant in a coolant line 214 and / or a temperature of the drive unit 4 and / or a temperature of the pressure medium. It is also conceivable to feed further input variables to the controller 20, as explained above.

Claims (15)

Hydraulic pressure medium supply arrangement for an open hydraulic circuit, with a hydraulic machine (2), with an adjusting mechanism (12), which has an adjusting cylinder (34) with an adjusting piston (36) for adjusting a delivery volume of the hydraulic machine (2) and which has an electrically proportional controllable pilot valve (14), wherein via the pilot valve (14) an inflow and / or an outflow in a control chamber (32) of the actuating cylinder (34) bounded by the actuating piston (36) can be controlled in order to control the actuating piston (36) To apply pressure medium, and wherein an electronic control (20) is provided, which as input variables at least a target output pressure (74) of the hydraulic machine (2) and / or a target delivery volume or target pivot angle (70) of the hydraulic machine (2) and which has a manipulated variable for the pilot valve (14) as the output variable, the controller (20) having a first control circuit (60) for an actual output pressure (52) of the hydraulic machine (2) and / or for an actual delivery volume or actual swivel angle (40) of the hydraulic machine (2), characterized in that the controller (20) has a second control loop (62) subordinate to the first control loop (60) for a delivery volume adjustment speed or swivel angle -Adjusting speed of the hydraulic machine (2), which has as an input variable an actual delivery volume adjusting speed or actual swivel angle adjusting speed (84) of the hydraulic machine and which has the manipulated variable (18) for the pilot valve (14) as an output variable, the second control loop (62) a control value (82) from the first control loop (60) in the form of a target delivery volume adjustment speed or target swivel angle adjustment speed (82) is supplied. Pressure medium supply arrangement according to claim 1, wherein the first control loop (60) of the controller (20) is designed for an actual torque (8) of the hydraulic machine (2), and wherein the input variable for the controller (20) is a setpoint torque (76) and the actual torque (8) is provided. Pressure medium supply arrangement according to claim 1 or 2, wherein the first control circuit (60) for the actual output pressure (52) of the hydraulic machine (2) and / or for the actual delivery volume or actual pivot angle (40) of the hydraulic machine (2) and / or outputs a manipulated variable for the actual torque (8) of the hydraulic machine (2), the controller (20) having an alternating control which has a minimum value generator (80) for the output manipulated variables (72, 75, 78). Pressure medium supply arrangement according to claim 3, wherein the first control circuit (60) for the actual output pressure (52) of the hydraulic machine (2) and / or for the actual delivery volume or Actual swivel angle (40) of the hydraulic machine (2) and / or for the actual torque (8) of the hydraulic machine (2) has a controller (110) with an I component, with the one having the I component when it is inactive Controller (110) or the controller (110) having the I component, the I component is frozen or partially or completely reduced. Pressure medium supply arrangement according to one of Claims 1 to 4, a setpoint pressure gradient (102) for regulating the actual output pressure (52) in the first control loop (60) being provided as an input variable. Pressure medium supply arrangement according to Claim 5, the setpoint pressure gradient (102) being adjustable to adapt the control dynamics of the pressure medium supply arrangement. Pressure medium supply arrangement according to Claim 5 or 6, the setpoint pressure gradient (102) being used to limit the change in the setpoint output pressure. Pressure medium supply arrangement according to one of the preceding claims, wherein a delivery volume adjustment speed specification or swivel angle adjustment speed specification (130) is provided as an input variable for the controller (20), which can be adjusted to adapt the control dynamics of the pressure medium supply arrangement. Pressure medium supply arrangement according to claim 8, wherein the delivery volume adjustment speed specification or swivel angle adjustment speed (130) is fed to a control element (128) which, as a further input variable, is the control value of the first control loop (60) in the form of the target delivery volume adjustment speed or setpoint Swivel angle adjustment speed (82), and wherein the control element (128) outputs a final target delivery volume adjustment speed (132) for the second control circuit (96) as an output variable, which is limited by the delivery volume adjustment speed specification (130). Pressure medium supply arrangement according to one of the preceding claims, wherein the highest actual load pressure (56) of consumers (168, 170), which are supplied by the pressure medium supply arrangement, is recorded as the actual load sensing (LS) pressure (56) and the control ( 20) is supplied as an input variable, and a desired pressure difference (100) is provided as an input variable for the controller (20), a desired pressure from the actual LS pressure (56) and the desired pressure difference (100) for the controller (20) is determined, which is provided as an input variable for the first control loop (60), and / or where actual LS pressures (56) from some of the consumers (168, 170) or from all consumers (168 , 170) are recorded by appropriate means, and a maximum value formation or prioritization of the actual LS pressures (56) takes place in the control (20). Pressure medium supply arrangement according to one of the preceding claims, wherein a filter (99, 112, 114, 126, 138) is provided for at least one input variable or for some of the input variables or for all input variables of the controller (20). Pressure medium supply arrangement according to one of the preceding claims, wherein one or a respective gain factor (Kp) for the first control loop (60) for regulating the actual output pressure (52) of the hydraulic machine (2) and / or for regulating the actual delivery volume (40 ) the hydraulic machine (2) and / or the regulation of the actual torque (8) of the hydraulic machine (2) is provided, the gain factor (Kp) depending on an actual temperature (154) and / or the actual speed ( 8) of the hydraulic machine (2) and / or of the actual output pressure (52) of the hydraulic machine (2) and / or of the setpoint pressure gradient (102) of the hydraulic machine (2). Pressure medium supply arrangement according to one of the preceding claims, wherein a neutral flow of the pilot valve (14) is pre-controlled. Pressure medium supply arrangement according to one of the preceding claims, wherein a valve slide of the pilot valve (14) is controlled in such a way that it temporarily or constantly executes an axial oscillating movement, the frequency and amplitude of the oscillating movement being controllable as a function of the actual output pressure Method with a hydraulic pressure medium supply arrangement according to one of the preceding claims, wherein the pilot valve (14) is controlled with the first and second control circuits (60, 62).

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