Method for using a hydraulic pressure medium supply device and hydraulic pressure medium supply device

Abstract

A method for using a hydraulic pressure medium supply device (100) for a hydraulic open circuit, comprising a hydraulic machine (10), an actuating mechanism (102) and an electronic control unit (1), is disclosed. The method comprises the steps of reading in a first outer control circuit (3) actual values ​​(16, 21, 25) of hydraulically actuated variables of the hydraulic machine and setpoint values ​​(15, 20, 24) associated with the actual values ​​(16, 21, 25) and determining a first actuated variable (18, 22, 26) resulting therefrom. In a further step of the method, in a second outer control circuit (5), the actual values ​​(16, 21, 25) of the hydraulically actuated variables and further setpoint values ​​(43, 45, 47, 77) are read and compared with one another, and at least one second actuated variable (33, 35, 37, 79) is determined therefrom. Subsequently, a target actuation speed (49, 73) is determined as an actuation variable for the actuation mechanism depending on the first actuation variable and the second actuation variable.Furthermore, a hydraulic pressure medium supply device (100) is disclosed which is configured for carrying out the method according to the invention.

Description

[Technical field]

[0001] The invention relates to a method using a hydraulic pressure medium supply device for a hydraulic open circuit according to the preamble of claim 1 and to a hydraulic pressure medium supply device according to claim 10. [Background technology]

[0002] From EP 3770428 A1 from Rexroth, a hydraulic pressure medium supply device with an operable axial piston machine is known. Here, the operating cylinder is driven by a control device with a cascaded control circuit consisting of an outer control circuit and an inner control circuit. The outer control circuit forms the manipulated variables as a function of the setpoints and actual values ​​of the axial piston machine, in particular the operating pressure, the swivel angle or the delivery volume and the torque. The smallest of these manipulated variables is then given priority via a minimum value former, so that the variable to be adjusted is determined as being at the upper limit compared to the setpoint.

[0003] However, such a regulation does not provide the possibility of limiting the manipulated variable of the outer control circuit downwards, especially if a limitation in the form of a minimum limit value is implemented on the system side, since only an upper limit of the manipulated variable is implemented by taking precedence via the minimum value former. For example, there may be a requirement on the pivot angle of the swash plate of the axial piston machine not to fall below a minimum pivot angle of the swash plate and thus below a predefined minimum delivery volume or displacement of the axial piston machine. This ensures, in particular, that a minimum volumetric flow rate for the load is always provided. If the actual operating pressure of the axial piston machine is higher than the defined target operating pressure, even though the predefined minimum delivery volume or displacement or the minimum pivot angle of the axial piston machine has already been reached, the pressure regulator of the outer control circuit will prescribe a negative manipulated variable value for the inner control circuit and will pivot the axial piston machine to reduce the pressure. At the same time, the swivel angle adjuster of the outer control circuit will output a positive or zero value in order to swivel the axial piston machine outward or to maintain the swivel angle so that it does not fall below the specified minimum swivel angle. Thus, if the smallest manipulated variable is given priority via the minimum value former in the superordinate sense, the operating pressure will be selected as the controlled variable / quantity to be adjusted, and the swivel angle will therefore be reduced even further below the specified minimum limit value. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] European Patent Application Publication No. 3770428 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention is based on the problem of providing a method for using a hydraulic pressure medium supply device, which allows a hydraulic working quantity, preferably a swivel angle or a displacement, an operating pressure or a torque of a hydraulic machine in the form of an axial piston machine to be limited / limited on the lower side. Furthermore, it is desirable to provide a hydraulic pressure medium supply device for carrying out the method. [Means for solving the problem]

[0006] The first of these problems is solved by a method having the features of claim 1, the second by a hydraulic pressure medium supply device having the features of claim 10. Advantageous embodiments and developments of the respective invention are the subject of the dependent claims.

[0007] The invention relates to a method for using a hydraulic pressure medium supply device for a hydraulic opening circuit, the hydraulic opening circuit comprising a hydraulic machine, preferably an axial piston machine, with an actuating mechanism, the actuating mechanism comprising an actuating cylinder with an actuating piston for actuating the displacement / delivery volume or the swivel angle of the hydraulic machine, and an electrically proportionally controllable (pilot) valve, by means of which the inflow into a control space defined by the actuating piston and / or the outflow from a control space defined by the actuating piston can be controlled for actuation, the valve being controlled via an electronic control unit of the hydraulic pressure medium supply device. The method comprises the steps of reading in a first external control circuit of the control unit respective actual values ​​and setpoint values ​​associated with the respective actual values ​​of the displacement volume or the swivel angle determinable from the displacement volume and / or of the operating pressure and / or torque of the hydraulic machine, and determining via the control unit a first actuating variable from a control deviation between the respective actual value and the setpoint value associated with the respective actual value. The method comprises the further step of determining a target operating speed of the displacement or the swivel angle in dependence on at least the first manipulated variable via a first external control circuit of the control unit. According to the invention, the method comprises the steps of reading respective actual values ​​of the displacement or the swivel angle and / or the operating pressure and / or the torque and a setpoint value associated with the respective actual values, and determining via the control unit at least one second manipulated variable from the respective actual values ​​and the setpoint value associated with the respective actual values, whereby the step of determining the target operating speed is performed further in dependence on the second manipulated variable.

[0008] In other words, the electronic control unit of the hydraulic pressure medium supply device has a first outer control circuit for a hydraulic controlled variable of a hydraulic machine, in particular of an axial piston machine, preferably for a swivel angle or a displacement or delivery volume, an operating pressure or a torque. This first outer control circuit has as input quantities the respective actual values ​​of the hydraulic machine and setpoint values ​​associated with the respective actual values. The first outer control circuit determines the first manipulated variable from an individual control deviation / control difference consisting of the difference between the respective setpoint and actual values. Additionally, the control unit has a second outer control circuit, preferably for the hydraulically manipulated variable. The second outer control circuit has as input quantities the respective actual values ​​of the hydraulic machine and defined / predetermined setpoint values ​​associated with the respective actual values. Preferably, these predetermined setpoint values ​​are minimum limit values. The second outer control circuit of the control unit determines the second manipulated variable from the control deviation of these input quantities. Preferably, one of these manipulated variables of the two outer control circuits is subsequently fed to an inner control circuit located downstream of the two outer control circuits as a target operating speed for the swivel angle or the displacement of the hydraulic machine. The inner control circuit further reads the actual operating speed as a derivative of the actual swivel angle or the actual displacement of the hydraulic machine and performs a comparison process between the target operating speed and the actual operating speed. Preferably, the selection of the manipulated variable fed to the inner control circuit is performed via a selection unit.

[0009] Thus, a method is provided for using a hydraulic pressure medium supply device, which makes it possible to limit / restrict the hydraulic working volume of a hydraulic machine at a lower side in order to comply with corresponding minimum limit values, e.g. a minimum pressure or a minimum volumetric flow rate which can be set via the swivel angle, in order to operate the components of the pressure medium supply device within the permitted range.

[0010] In a further aspect of the invention, at least one of the second manipulated variables represents a limit of the operating pressure dependent on a maximum allowable operating pressure.

[0011] In an advantageous embodiment of the invention, a regulator is located / connected downstream of the second outer control circuit of the control unit, and the step of limiting the operating pressure in dependence on the maximum permissible operating pressure is implemented via this regulator located downstream of the second outer control circuit. Alternatively, a regulator for cutting off the pressure is configured as the second outer control circuit of the control unit, and the method step of limiting the operating pressure in dependence on the maximum permissible operating pressure is implemented via this regulator as the second outer control circuit.

[0012] In other words, the method comprises a (additional) step of cutting off the pressure. The corresponding regulator is preferably located / connected upstream of the further minimum former, so that the pressure cut-off function in this embodiment of the electronic control unit has the highest priority. This makes the device comparable to the most downstream control axis of a hydromechanical regulator. Preferably, the regulator for cutting off the pressure is provided with separate parameters and setpoint definitions in order to allow different dynamics and setpoints compared to the operating pressure regulator in the first outer control circuit. Thus, the pressure regulation dynamics definition and pressure cut-off definition and the pressure cut-off dynamics are separated and can be set separately from each other.

[0013] In a further aspect of the invention, the method comprises a step of prioritizing the smallest of the first manipulated variables via a minimum value former of the control unit, in which case the step of determining the target manipulated variable speed is performed depending on at least the prioritized smallest of the first manipulated variables.

[0014] In other words, the selection unit of the electronic control unit has a determination device, preferably in the form of a minimum value former, which has as input quantities the output quantities of the first outer control circuit in the form of a first manipulated variable. The minimum value former then prioritizes / selects from these input quantities the manipulated variable having the smallest value as the target operating speed. Due to this selection, only the regulator of the first outer control circuit, which is associated with the controlled variable prioritized by the minimum value former, is automatically activated. In this case, the manipulated variable having the smallest control deviation is the leading controlled variable, and either the swivel angle or the displacement, the operating pressure or the torque is regulated exactly, while the two other quantities, respectively, are below their respective defined target values.

[0015] This selection via the minimum value former results in the final adjustment of the controlled variable having an actual value that is at the upper limit compared to the respectively assigned setpoint value via the first outer control circuit. For example, the controlled variable having an actual value that is the most above the corresponding setpoint value is given priority, since this results in the lowest / most negative actuated variable. This achieves an upper limiting of the hydraulic actuating variable.

[0016] In a further aspect of the invention, at least one of the second manipulated variables represents limiting a minimum target swing angle and / or a minimum target displacement and / or a minimum target output pressure and / or a minimum target torque.

[0017] In a further aspect of the invention, the method further comprises a step of prioritizing the largest manipulated variable from the second manipulated variable and the smallest manipulated variable of the first manipulated variables, which is prioritized by the minimum value former, via a maximum value former of the control unit, in which case the step of determining the target manipulated variable is performed depending on the largest prioritized manipulated variable.

[0018] In other words, the selection unit of the electronic control unit has a second determination device, preferably in the form of a maximum value former, which has as input quantities the smallest manipulated variable prioritized by the minimum value former in the form of a target manipulated speed from the first outer control circuit and a manipulated variable from the second outer control circuit, which prioritizes the manipulated variable having the largest value from these input quantities and outputs as output quantity the prioritized target manipulated speed based on this MAX selection.

[0019] Due to the priority given by the maximum value former, the electronic control unit always adjusts the controlled variables that are below the minimum setpoint value assigned to them. If all actual values ​​of the hydraulic operating variables are greater than the predefined minimum setpoint / limit value, the second outer control circuit outputs a value less than zero for the controlled variable. A comparison is then made between the value less than zero and the operating variable from the first outer control circuit that is given priority by the minimum value former, and the maximum value former then gives priority to the larger value. This achieves a lower limiting of the hydraulic operating variables of the hydraulic machine, since priority is given to adjusting the hydraulic operating variables that are below the predefined minimum setpoint value. In this case, for example, the slewing behavior of the hydraulic pump is defined by the parameters of the regulator.

[0020] Additionally, a further selection unit can be connected upstream of the maximum value former, which blocks the (output) manipulated variable of the second outer control circuit or prevents it from being fed to the maximum value former if the manipulated variable of the second outer control circuit has a maximum negative value for all controlled variables, i.e. if it does not fall below any of the minimum setpoint values. In such a case, the manipulated variable prioritized by the minimum value former is always prioritized by the downstream maximum value former, since no adjustment via the second outer control circuit is necessary here.

[0021] According to a further aspect of the invention, the method includes a step of reading, in an inner control circuit located downstream of the first outer control circuit of the control unit, an actual actuation speed and a target actuation speed determined depending on at least a first actuation variable.

[0022] According to a further aspect of the invention, the method comprises a step of limiting the determined target operating speed based on the output quantities of the two outer control circuits in dependence on a predetermined maximum target operating speed and / or a predetermined minimum target operating speed via a regulator located upstream of the inner control circuit of the control unit.

[0023] In other words, an additional regulator is connected downstream of the maximum value former, preferably for limiting / restricting / prescribing the target actuation speed of the swivel angle or displacement of the hydraulic machine. Through an additionally defined upper and / or lower limit of the preferably actuable actuation speed, the actuation quantity of the maximum value former is limited in particular in order to influence the control dynamics of the pressure medium supply device and to limit the dynamics for the inward and outward swivel. This limit can be, for example, a positive or negative maximum value of the actuation speed. The higher the target actuation speed, the faster the hydraulic machine can be swiveled outward. This allows the dynamics of the hydraulic machine to be controlled externally, independently of the provisions of the (first) outer control circuit, or internally, in order to protect the components. For example, it is possible to avoid cavitation and thus deceleration of the hydraulic machine, even though relatively high swivel angles / actuation speeds are required in the system in order to adjust the actuation quantities more quickly.

[0024] If the above-mentioned regulators of the (inner and / or outer) control circuit and / or the regulators located upstream for limiting the target operating speed and / or the regulators located downstream for cutting off the pressure comprise at least one regulator with an I component, the method according to the invention preferably comprises a step of freezing or reducing the I component of the regulator with the non-prioritized operating variable.

[0025] In other words, the regulator of the electronic control unit is preferably configured as a PID regulator, the I component of which is (partially) reset or frozen if the corresponding regulator is not active, i.e. not prioritized by a minimum or maximum former, because another regulator or another controlled variable prevails. For this reason, after each priority step / priority process via a minimum or maximum former or a limit block, in addition to the value of the respective output / manipulated variable, the status of which regulator is prioritized is also reported. Depending on this status, the corresponding I component of the regulator is activated or deactivated. This avoids the winding up of the regulator when another regulator / other regulating function is prioritized, i.e. the so-called wind-up phenomenon.

[0026] In a further aspect of the invention, if the inner control circuit has an adjustment part which is pilot-controlled via a pilot control value with an I component and the manipulated variable of the adjustment part is limited via a manipulated variable limiting device, the method comprises a step of limiting the I component via the I component limiting device depending on the pilot control value and the limitation by the manipulated variable limiting device.

[0027] In other words, if the output quantity of a regulator with an I component, preferably of an inner control circuit, is composed of a pilot control component / feedforward component and a regulator component, and this output quantity is additionally limited / limited, then the method limits the I component of the regulator in dependence on the pilot control component, so that the limit / limit of the output quantity at the (total) output of the regulator is respected. In that case, the regulator only operates up to saturation in the total and does not have an absolute anti-wind-up limit. For example, the total output of a pilot-controlled regulator, consisting of a pilot control component and a (PID) regulator component, can be limited by a manipulated variable limit. Depending on the operating state of the hydraulic machine, a part of the manipulated variable is pilot-controlled. The difference between the pilot control component and the manipulated variable limit is thus additionally provided to the (PID) regulator. The I component of the regulator is accordingly limited so that the total output is not greater than the prescribed manipulated variable limit. The limiting of the I component is therefore: I Limit = Controlled variable limit - pilot control component or I Limit = Controlled variable limit - Pilot control component - P component It becomes.

[0028] This ensures that the regulator does not wind up and thus no additional phase shift or time delay occurs.

[0029] In a further aspect of the invention, the method comprises determining, via a current regulator, a drive control signal for the valve as a function of the target neutral signal value and the actual signal value.

[0030] In other words, the output quantity / operating variable of the inner control circuit in the form of a current signal is summed with the pilot control value of the pilot control device, so that the neutral current of the (pilot) valve of the hydraulic pressure medium supply device is pilot controlled. The desired neutral signal value obtained from this is compared with the actual signal value via a current regulator, preferably in the form of a PID regulator, so that the subsequent operating quantity / drive control signal is supplied to the valve.

[0031] The invention further relates to a hydraulic pressure medium supply device for a hydraulic opening circuit, the hydraulic opening circuit comprising a hydraulic machine with an actuating mechanism, the actuating mechanism having an operating cylinder with an operating piston for actuating the displacement or the swivel angle of the hydraulic machine and an electrically proportionally controllable (pilot) valve, the flow into and / or out of the control space of the operating cylinder defined by the operating piston being controllable via the valve in order to apply pressure medium to the operating piston for actuation, the hydraulic opening circuit comprising an electronic control unit, the electronic control unit being signal-connected to a distance detector of the valve, to a pressure sensor and to an actuator, the hydraulic opening circuit being configured for carrying out the method according to the invention.

[0032] In the following, the invention will be explained in more detail based on preferred embodiments and with reference to the attached drawings, which are only schematic in nature and serve only as an aid to the understanding of the invention. It should be noted that the features of the individual embodiments are mutually interchangeable and may be realized in any combination. [Brief description of the drawings]

[0033] [Figure 1] FIG. 2 is a schematic diagram of an electronic control unit with input and output quantities according to a first embodiment; [Diagram 2] FIG. 2 is a schematic diagram of the electronic control unit of FIG. 1 with an additional adjustment for limiting the turning speed according to a second embodiment. [Diagram 3] FIG. 3 is a schematic diagram of the electronic control unit of FIG. 2 with an additional regulator for pressure cut-off according to a third embodiment. [Figure 4] FIG. 1 is a schematic diagram of a pilot-controlled PID regulator with a dynamically limited I component. [Diagram 5] 1 is a schematic diagram of a hydraulic pressure medium supply device with a hydraulic machine with an operating mechanism and an electronic control unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] FIG. 1 shows an electronic control unit 1 according to a first embodiment with a first outer control circuit 3, a second outer control circuit 5 and an inner control circuit 7. The first outer control circuit 3 has a regulator 9 for the swivel angle of a swash plate of a hydraulic machine 10, preferably an axial piston machine, a regulator 11 for the operating pressure of the hydraulic machine 10 and a regulator 13 for the torque of the hydraulic machine 10. In this case, the regulator 9 has as input quantities the setpoint and actual swivel angle of the hydraulic machine 10. The output quantity of the regulator 9 forms a manipulated variable 18. The regulator 11 has as input quantities the setpoint and actual operating pressure of the hydraulic machine 10. As output quantity of the regulator 11, a manipulated variable 22 is provided. The regulator 13 has as input quantities the setpoint and actual torque of the hydraulic machine 10, whereas the output quantity of the regulator 13 forms a manipulated variable 26. The regulators 9, 11, 13 each comprise one regulator part in the form of a PID regulator in this embodiment of the control unit 1.

[0035] The three manipulated variables 18, 22, 26 of the first outer control circuit 3, which are formed from the control deviation between the setpoint and the actual value, are fed to a minimum value former 27, which ensures that only the regulator 9, 11 or 13 associated with the desired operating point is automatically activated. In this case, the manipulated variable with the smallest control deviation is the leading manipulated variable, and either one of the actuation angle, the operating pressure or the torque is adjusted exactly, while the two other variables, respectively, are below their respective setpoint values. The output variable of the minimum value former 27 forms a target actuation speed 29 of the swivel angle, which is fed as an input variable to a maximum value former 31. Further input variables of the maximum value former 31 are the output variables or manipulated variables 33, 35, 37 of the respective regulators 39, 40 and 41 of the second outer control circuit 5. In this case, the minimum setpoint swivel angle 43 and the actual swivel angle 16 of the hydraulic machine 10 form the input variables of the regulator 39. The regulator 40 has as input quantities the minimum desired operating pressure 45 and the actual operating pressure 21 of the hydraulic machine 10, whereas the regulator 41 has as input quantities the minimum desired torque 47 and the actual torque of the hydraulic machine 10. In this illustrated embodiment of the control unit 1, the regulators 39, 40 and 41 of the second outer control circuit 5 are likewise configured in the form of a PID regulator. The maximum value former 31 ensures that only the regulator with the largest control error is active, either the regulator 39, 40 or 41 of the second outer control circuit 5 or the regulator 9, 11 or 13 of the first outer control circuit 3, which is prioritized by the minimum value former 27. The output quantity of the maximum value former 31 is the desired operating speed 49 of the swivel angle, which is supplied as an input quantity to the inner control circuit 7. This inner control circuit 7 has a regulator 51 in the form of a PID regulator. A further input variable for the regulating element 51 is the actual actuation speed 53 of the swivel angle, which is obtained from the time derivative of the actual swivel angle 16. The regulating element 51 of the inner control circuit 7 has as output variable a manipulated variable 55 in the form of a current, which is summed with a pilot control value 57 of a pilot control device 58, by which the neutral current of a valve 59 (see FIG. 5) is pilot controlled.Based on this pilot control, a target valve current 60 for the valve 59 is obtained, which is supplied as an input to a current regulator 62 with a PID part. The current regulator 62 adjusts an actual valve current 65 based on the target valve current 60, thereby outputting a drive control signal 67 for the valve 59.

[0036] FIG. 2 shows an electronic control unit 1 according to a second embodiment with a first outer control circuit 3, a second outer control circuit 5 and an inner control circuit 7. This embodiment of the electronic control unit 1 has all the components of the electronic control unit 1 of the embodiment shown in FIG. 1 and has an additional extension by a regulating unit 69 for limiting the actuation speed, whereby the target actuation speed 49 is additionally limited above and below. The regulating unit 69 has as input quantities the output quantity of the maximum value former 31 in the form of the target actuation speed 49, a maximum target actuation speed 70 and a minimum target actuation speed 71. The possibly limited target actuation speed 73 forms the output quantity of the regulating unit 69 and the input quantity of the inner control circuit 7. The remaining control sequence of the electronic control unit 1 according to this second embodiment up to the output of the drive control signal 67 is carried out according to the first embodiment of the electronic control unit 1 (see FIG. 1).

[0037] 3 shows an electronic control unit 1 according to a third embodiment. This embodiment of the electronic control unit 1 has all the components of the electronic control unit 1 of the second embodiment shown in FIG. 2 and is extended by an additional regulating element 75 with a pressure cut-off function, which regulates the actual working pressure 21 separately if the actual working pressure 21 exceeds a defined maximum working pressure 77. The regulating element 75 has as input variables a setpoint value definition in the form of a maximum working pressure 77 of the hydraulic machine 10 and the actual working pressure 21. Furthermore, the regulating element 75 is configured in the form of a PID element and has as output variable a setpoint operating speed 79, which flows as input variable into a second inner minimum value former 80. The output variable of the maximum value former 31 in the form of the setpoint operating speed 49 in this case forms the second input variable of the inner minimum value former 80. The inner minimum former 80 prioritizes the smaller of the target operating speeds 49 and 79 as the operating quantity and outputs the prioritized target operating speed 81 as an output quantity, which then flows as an input quantity to the regulator 69 for limiting the operating speed (see also FIG. 2). According to this arrangement, the regulator 75 for cutting off the pressure has the highest priority. The remaining control sequence of the electronic control unit 1 according to this third embodiment up to the output of the drive control signal 67 is performed according to the second embodiment of the electronic control unit 1 (see FIG. 2).

[0038] 4 shows a possible embodiment of the regulator 51 of the inner control circuit 7, which is pilot controlled by a pilot control device 58. The regulator 51 in the form of a PID regulator has a setpoint value 83 and an actual value 84 as input variables, and a control deviation 85 is calculated from the difference between these setpoint value 83 and actual value 84. The control deviation 85 is divided into a P component 87, an I component 88 and a D component 89, and the control deviation 85 is multiplied by an amplification factor Kp or passes through an I section 90 and then multiplied by an amplification factor Ki or passes through a D section 91 and then multiplied by an amplification factor Kd. In particular, the I component 88 passes through an I component limiter 93 and then summed with the P component 87 and the D component 89, and the manipulated variable 94 obtained from this is then summed in a further summation block 95 with the pilot control value 57 of the pilot control device 58. The total output, which is made up of the pilot control value 57 and the manipulated variable 94, further passes through a manipulated variable limiter 97, which outputs an output value 98. The I component 88 of the regulating part 51 is limited in dependence on the pilot control value 57 so that the manipulated variable limit in the total output is observed. Thus, the limiting of the I component 88 is performed dynamically in dependence on the manipulated variable limit by the manipulated variable limiter 97 and on the pilot control value 57.

[0039] FIG. 5 shows a hydraulic pressure medium supply device 100 with a hydraulic machine 10 in the form of an axial piston machine. The axial piston machine has a cradle for adjusting the delivery volume. The hydraulic machine 10 can be used both as a pump and as a motor. An actuation mechanism 102 is provided for the hydraulic machine 10. The actuation mechanism 102 has a valve 59. A valve spool of the valve 59 can be electrically proportionally actuated via an actuator 104. For this purpose, the actuator 104 is supplied with an actuation signal 67 from the electronic control unit 1. The valve spool of the valve 59 is subjected to a spring force of a valve spring 105 in the direction of a basic position. In this case, the spring force acts against the actuator force of the actuator 104. The hydraulic machine 10 is connected on the output side to a pressure line 107, which is itself connected to a main control valve or valve block, not shown. A control line 109 branches off from the pressure line 107 and is connected to a pressure connection of the valve 59. The control line 109 is arranged, for example, in the housing of the hydraulic machine 10. Furthermore, the valve 59 has a tank connection, which is connected to a tank (not shown) via a tank line 111. Furthermore, the valve 59 has a working connection which is connected to a control space 113 of an actuating cylinder 115. In this case, the control space 113 is defined by an actuating piston 116 of the actuating cylinder 115. A swash plate of the axial piston machine or hydraulic machine 10 can then be actuated via the actuating piston 116. The travel distance of the actuating piston 116 is captured via a distance detector 118. Alternatively or additionally, the pivot angle of the cradle of the axial piston machine or hydraulic machine 10 is measured from the pivot axis of the cradle via a rotary magnetic sensor. Via the captured distance, the actual delivery or displacement volume or the actual swivel angle 16 of the hydraulic machine 10 can then be determined, which are communicated to the electronic control unit 1 .

[0040] The actuating mechanism 102 is further provided with a cylinder 120. The cylinder 120 has an actuating piston 121 which engages with the swash plate of the axial piston machine 10. The actuating piston 121 defines a control space 122 which is connected to the pressure line 107. Via the pressure medium in the control space 122 and via the spring force of a spring 123, the actuating piston 121 is applied with a load on the swash plate in the direction of increasing the delivery volume. Furthermore, a pressure sensor 125 is provided by means of which the pressure in the pressure line 107 is measured and communicated to the control unit 1, which in this case is the actual operating pressure 21.

[0041] When the pressure medium supply device 100 is used, the position of the swash plate of the axial piston machine 10 is controlled via the valve 59 and the operating piston 116. The volumetric flow rate of the axial piston machine 10 delivered is proportional to the position of the swash plate. The actual operating pressure or pump pressure is always applied to the operating piston 121 or the counter piston, which is biased by the spring 123. If the axial piston machine 10 is not rotating and the operating mechanism 102 is pressureless, the spring 123 holds the swash plate in the +100% position. If the axial piston machine 10 is driven and the actuator 104 of the valve 59 is currentless, the swash plate pivots up to the zero stroke pressure, because the pressure medium in the pressure line 107 is applied to the operating piston 116. The balance between the actual operating pressure at the operating piston 116 and the spring force of the spring 123 occurs at a certain pressure or pressure range, for example between 8 and 12 bar. This zero stroke operation is assumed, for example, when there is no voltage in the electronics or control unit 1. For example, the actuation control of the valve 59 is performed via the control unit 1, which is preferably a digital electronic device, alternatively an analog electronic device. The control unit 1 processes the necessary control signals. [Explanation of symbols]

[0042] 1 Electronic Control Unit 3 First outer control circuit 5 Second outer control circuit 7 Inner control circuit 9, 11, 13 First outer control circuit regulator 10 Hydraulic Machines / Axial Piston Machines 15 Target turning angle / target displacement 16 Actual turning angle / actual displacement 18, 22, 26 Operation amount of the first outer control circuit 20 Target Operating Pressure 21 Actual operating pressure 24 Target Torque 25 Actual Torque 27 Minimum Value Former 29 Target operating speed of the first outer control circuit 31 Maximum Value Forming Device 33, 35, 37 Operation variable of the second outer control circuit 39, 40, 41 Second outer control circuit regulator 43 Minimum target turning angle / minimum target displacement 45 Minimum target output pressure 47 Minimum target torque 49 Target operating speed of second outer control circuit 51 Adjustment section of the inner control circuit 53 Actual operating speed 55 Operation amount of the inner control circuit 57 Pilot Control Value 58 Pilot Control Device 59 (Pilot) Valve 60 Target valve current value 62 Current regulator 65 Actual valve current value 67 Drive control signal 69 Regulator for limiting operating speed 70 Maximum target operating speed 71 Minimum target operating speed 73 Limited target maneuver speed 75 Pressure cut-off regulator 77 Maximum Operating Pressure 79 Target operating speed of regulator for pressure cutoff 80 Inner minimum former 81 Target operation speed 83 Target value 84 Actual Value 85 Control deviation 87 P component 88 I component 89 D component 90 Part I 91 D section 93 I component limiting device 94 Manipulated amount 95 total blocks 97 Operation amount limiting device 98 Output Value 100 Hydraulic pressure medium supply device 102 Operating mechanism 104 Actuator 105 Valve spring 107 Pressure Pipeline 109 Control Pipe 111 Tank Pipeline 113 Control Space 115 Operating cylinder 116 Operating piston 118 Distance Detector 120 cylinder 121 Operating piston 122 Control Space 123 Spring 125 Pressure Sensor

Claims

1. A method for using a hydraulic pressure medium supply device (100) for a hydraulic open circuit, comprising the steps of: The hydraulic open circuit comprises a hydraulic machine (10) having an operating mechanism (102), The operating mechanism (102) has an operating cylinder (115) equipped with an operating piston (116) for operating the displacement or the rotation angle of the hydraulic machine (10), and a valve (59) that can be electrically proportionally driven and controlled; via said valve (59) the flow into and / or out of said control space (113) of said operating cylinder (115) defined by said operating piston (116) is controllable for operation, The hydraulic opening circuit includes an electronic control unit (1) for controlling the operation of the valve (59), The method comprises: a) reading in a first external control circuit (3) of the control unit (1) actual values ​​(16, 21, 25) of the displacement or swivel angle of the hydraulic machine (10) and / or of the operating pressure and / or torque of the hydraulic machine (10) and setpoint values ​​(15, 20, 24) associated with the respective actual values ​​(16, 21, 25); b) determining, via the control unit (1), a first manipulated variable (18, 22, 26) from each of the actual values ​​(16, 21, 25) and a setpoint value (15, 20, 24) associated with each of the actual values ​​(16, 21, 25); c) determining, via said control unit (1), a target actuation speed (49; 73) as a function of at least said first actuation variable (18, 22, 26); A method comprising: d) reading the actual values ​​(16, 21, 25) of the displacement or the swivel angle and / or the operating pressure and / or the torque and the setpoint values ​​(43, 45, 47, 77) associated with the respective actual values ​​(16, 21, 25); e) determining, via the control unit (1), at least one second manipulated variable (33, 35, 37, 79) from the respective actual value (16, 21, 25) and a setpoint value (43, 45, 47, 77) associated with the respective actual value (16, 21, 25), whereby the step of determining the setpoint manipulated variable (49; 73) is performed further in dependence on the second manipulated variable (33, 35, 37, 79); 23. A method comprising:

2. At least one of the second manipulated variables represents a limit of the operating pressure (77) depending on a maximum allowable operating pressure (77). The method of claim 1.

3. The method comprises: giving priority to the smallest of the first manipulated variables (18, 22, 26) via a minimum value former (27) of the control unit (1); Equipped with Furthermore, the step of specifying the target operation speed (49; 73) is performed depending on the smallest operation amount prioritized among at least the first operation amount (18, 22, 26). The method according to claim 1 or 2.

4. at least one of the second manipulated variables represents limiting a minimum target swing angle and / or a minimum target displacement and / or a minimum target output pressure and / or a minimum target torque.

4. The method according to claim 1 .

5. The method comprises: Prioritizing the largest of the second manipulated variables (33, 35, 37) and the smallest prioritized one of the first manipulated variables (18, 22, 26) via a maximum value former (31) of the control unit (1). Equipped with Furthermore, the step of identifying the target operation speed (49; 73) is performed depending on the largest operation amount that is prioritized. The method according to claim 4.

6. The method comprises: in an inner control circuit (7) downstream of the first outer control circuit (3) of the control unit (1), reading the actual actuation speed (53) and the target actuation speed (49; 73) determined in step c), Equipped with 6. The method according to any one of claims 1 to 5.

7. The method comprises: limiting the target actuation speed (49) in dependence on a predefined maximum target actuation speed (70) and / or a predefined minimum target actuation speed (71) via a regulator (69) located upstream of the inner control circuit (7) of the control unit (1), Equipped with The method according to claim 6.

8. the inner control circuit (7) has a regulator (51) which is pilot-controlled via a pilot control value (57) with an I component (88), the manipulated variable of the regulator (51) being limited via a manipulated variable limiting device (97); The method comprises: limiting the I component (88) via an I component limiting device (93) as a function of the pilot control value (57) and the limiting by the manipulated variable limiting device (97) Equipped with The method according to claim 6 or 7.

9. The method comprises: determining, via a current regulator (62), a drive control signal (67) for said valve (59) as a function of the target valve current value (60) and the actual valve current value (65); Equipped with 9. The method according to any one of claims 1 to 8.

10. A hydraulic pressure medium supply device (100) for a hydraulic open circuit, comprising: The hydraulic opening circuit comprises a hydraulic machine (10) having an operating mechanism (102), The operating mechanism (102) has an operating cylinder (115) equipped with an operating piston (116) for operating the displacement or the rotation angle of the hydraulic machine (10), and a valve (59) that can be electrically proportionally driven and controlled; via the valve (59) it is possible to control the flow of pressure medium into and / or out of a control space (113) of the operating cylinder (115) defined by the operating piston (116) in order to apply pressure medium to the operating piston (116) for operating the operating piston, The hydraulic opening circuit includes an electronic control unit (1), The electronic control unit (1) is in signal connection with the distance detector (118) of the valve (59), with the pressure sensor (125) and with the actuator (104) and is configured to perform the method according to any one of claims 1 to 9. Pressure medium supply device (100).

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