Hydraulic pressure medium supply assembly, method and mobile working machine

Abstract

The present invention relates to a hydraulic pressure medium supply assembly having: a hydraulic press for supplying pressure medium to at least one hydraulic load, a hydraulic control block for controlling at least one load, and first and second control modules, wherein the control block can be controlled by the first control module via at least one adjustment signal, wherein a data interface is provided between the control modules, and the first control module transmits, as another adjustment signal, the rated output pressure for the hydraulic press and / or the rated delivery volume for the hydraulic press as input parameters to the second control module via the data interface, wherein the second control module controls the adjustment mechanism of the hydraulic press using a valve adjustment signal based on the rated output pressure and / or based on the rated delivery volume, and transmits at least one hydraulic parameter and / or another adjustment signal to the second control module for the data interface, and the hydraulic parameter and / or the signal predetermine and / or limit the dynamic characteristics of the adjustment mechanism of the hydraulic press.

Description

TECHNICAL FIELD

[0001] The present invention relates to a hydraulic pressure medium supply assembly for an open hydraulic circuit, for example for a mobile working machine, according to the preamble of claim 1. BACKGROUND ART

[0002] A pressure and delivery flow control system is known from the literature RD 30630 / 04.13 of Rexroth. This pressure and delivery flow control system is used to electrohydraulically control the swivel angle, pressure and power of an axial piston regulating pump. The control system has an axial piston regulating pump with an electrically controlled proportional valve. The regulating piston can be controlled by this control system. This regulating piston is used to adjust the swashplate of the regulating pump. A displacement sensor is provided for the regulating piston, by means of which the swivel angle of the swashplate can be determined by means of the displacement of the regulating piston. As an alternative to the displacement sensor, the swivel angle of the swashplate on the swivel axis can also be measured by a Hall sensor. The volume flow of the regulating pump can be determined from the swivel angle of the swashplate. The regulating pump is driven by a motor. If the regulating pump is not driven and the control system is pressureless, the regulating pump swings to the maximum delivery volume by the spring force of a spring. In contrast, in the driven state of the regulating pump and when the pilot valve is de-energized and the pump outlet is closed, the regulating pump swings to the zero-stroke pressure. The balance between the pump pressure on the regulating piston and the spring force of the spring occurs at approximately 4 to 8 bar. The basic setting is usually used in a voltage-free control electronics. The control device for the pilot valve has the rated pressure, the rated swivel angle and optionally the rated power value as input parameters. The actual pressure on the output side of the regulating pump is detected by a pressure sensor. As described above, the actual swivel angle is determined by a displacement sensor. The recorded actual parameters are digitally processed in an electronic unit and compared with the pre-given rated values. The minimum value generator then ensures that only the controller assigned to the desired operating point is automatically activated. The output signal of the minimum value generator is then the rated value for the proportional magnet on the pilot valve. To control the pilot valve, the displacement of the spool of the pilot valve is detected by a displacement sensor and notified to the control device. In the literature RD 30242 / 03.10 of Rexroth, an external control electronics for the described regulation of an axial piston regulating machine is disclosed. In addition, in the literature RD 92 088 / 08.04 of Rexroth, an electrohydraulic control system is disclosed.

[0003] A decoupled control of pressure and delivery flow is disclosed by EP 1 460 505 A2. Herein, a swingable hydraulic axial piston regulating machine is provided, which is connected to another hydraulic machine via a transmission shaft. In addition, a control circuit for the drive torque of the regulating machine is provided. The actual drive torque and the rated drive torque are fed to the control circuit, whereby a control parameter for the regulating device of the regulating machine is determined. The rated drive torque is in turn an output parameter of a minimum value generator. Herein, the minimum value generator selects the output parameters of pressure control and volume flow control. Herein, the volume flow of the hydraulic machine connected to the regulating machine is set as the actual volume flow. In addition, the high pressure of the hydraulic machine is set as the actual pressure.

[0004] In addition, a hydraulic machine with a swing angle sensor and a pressure sensor is respectively disclosed in documents EP 2 851 565 B1, JP 4 801 247, JP 5182 908, EP 034 9092 B1, US5 / 267,441, US 5 / 967,756 and US 5 / 170,625. Pressure, volume and power can be controlled.

[0005] In addition, a flow distribution (LUDV) system independent of load pressure is also known from the prior art. The LUDV system or LUDV control device refers to a special case of a load sensing (LS) control device, in which the highest load pressure is notified to the regulating pump and the regulating pump is controlled in such a way that there is a pump pressure in the pump line that exceeds the load pressure by a specific pressure difference δp. The adjustable metering orifice plate of the LS control device is equipped with individual pressure balances, and these individual pressure balances also maintain a constant pressure difference through the metering orifice plates of the hydraulic loads with relatively lower corresponding load pressures. In a control assembly commonly referred to as an LS control device, the individual pressure balances are arranged upstream of the metering orifice plate and throttle the fluid flow so strongly between the pump line and the metering orifice plate that the pressure before the metering orifice plate is only still higher than the individual load pressure by a specific pressure difference independently of the pump pressure. Herein, in case of insufficient supply, the load with the highest load pressure slows down because the pump pressure existing before its metering orifice plate drops and thus the pressure difference across this metering orifice plate becomes smaller. In the case of the LUDV control device, the individual pressure balances are arranged downstream of the metering orifice plate and throttle the fluid flow so strongly between the metering orifice plate and the load that the pressures after all metering orifice plates are the same, preferably equal to the highest load pressure or slightly higher than this load pressure. Here, there is no change when the pressure supply downstream of the metering orifice plate is insufficient. The pump pressure exists in the same way in front of all metering orifice plates, so that across all metering orifice plates, when the pump pressure becomes smaller due to insufficient supply, the pressure difference changes in the same way and the flow distribution between the metering orifice plates is maintained.

[0006] In the described control device, the regulation of the regulating pump is carried out by a hydro-mechanical pump governor (differential pressure regulation (DFR)). The pressure difference δp or differential pressure is preset by the spring preload on the pump governor. Once the pump pressure is lower than the set differential pressure, the control edge on the spool at the pump governor is opened in such a way that the displacement of the regulating pump increases. When this differential pressure is reached, the pump governor reaches its regulating position, so that the displacement of the regulating pump is maintained in a steady state. If the pump pressure is greater than the set differential pressure, the displacement of the regulating pump is correspondingly reduced until the rated pump pressure is reached. The adjustable differential pressure can be achieved by using an electro-hydraulic pump governor.

[0007] In addition to the function of differential pressure regulation, it may also be necessary to limit the power of the regulating pump, because the swivel power of the regulating pump is usually greater than the available drive power of the drive unit, which is, for example, an electric motor or an internal combustion engine, such as a diesel engine. This is usually achieved by using additional components. The superimposed electronic or mechanical regulating circuit limits the swing angle or displacement of the regulating pump according to the pressure level, so that the maximum torque is not exceeded or the power remains constant. This is disclosed, for example, in DE 102010 0200 04.

[0008] The dynamic characteristics of the above system can only be variably adjusted to a limited extent. In particular, the dynamic characteristics of the regulating pump are adjusted by setting the nozzle and spring stiffness on the pump governor, and it is fixed for operation in the pressure medium supply assembly and cannot be changed any more. In addition, the dynamic characteristics of the regulating pump are related to the pump pressure. The influencing parameters that define the system dynamic characteristics are especially the rotational speed, pump pressure, temperature of the pressure medium, volume of the pressure medium in the hydraulic pipeline, stiffness of the pipeline / drilling, kinematics of the working equipment, rated differential pressure and external disturbing forces. The regulating pump must ensure the highest dynamic characteristics and stability in all cases. Therefore, a compromise is needed in the design of the regulating pump. In a working machine, the system is very prone to vibration quickly, because different loads, such as hydraulic cylinders or hydraulic presses, have different system responses. This will result in the movement of the load being felt as sudden, because the regulating pump does not have the best dynamic characteristics in all cases. Summary of the Invention

[0009] In contrast, the object of the present invention is to provide a hydraulic pressure medium supply assembly that is simply and inexpensively designed in terms of device technology and has relatively high dynamic characteristics and stability. In addition, the object of the present invention is to provide a method and a mobile working machine for the pressure medium supply assembly.

[0010] The object regarding the pressure medium supply assembly is solved by the features of claim 1, the object regarding the method is solved by the features of claim 9, and the object regarding the mobile working machine is solved by the features of claim 10.

[0011] Advantageous refinements of the invention are the subject matter of the dependent claims.

[0012] According to the invention, a hydraulic pressure medium supply assembly for an open hydraulic circuit, in particular for a mobile working machine, is provided. The pressure medium supply assembly has a hydraulic machine, in particular a regulating pump, for supplying pressure medium to at least one hydraulic load. In addition, the pressure medium supply assembly can have a hydraulic control block which has one or more valves or valve plates. The hydraulic control block is used to control at least one load. The hydraulic machine is preferably connected to the control block. In addition, the pressure medium supply assembly can have a first and a second control module. The control block can be controlled by the first control module via at least one regulating signal or via a plurality of regulating signals. A data interface is advantageously provided between the control modules. For example, the control modules have a common data line to which the control modules are connected. It is preferably provided that the first control module provides the second control module via the data interface, as additional regulating signals, input variables such as the nominal output pressure measured, for example, on the output side of the hydraulic machine, or the pump pressure for the hydraulic machine and / or the nominal delivery volume or nominal swing angle for the hydraulic machine and / or the nominal torque for the hydraulic machine. The second control module can then preferably control the regulating mechanism or the regulation of the hydraulic machine by means of valve regulating signals using the nominal output pressure and / or the nominal delivery volume and / or the nominal torque. It is advantageously provided that at least one hydraulic parameter and / or another regulating signal is transmitted to the second control module via the data interface, in particular from the first control module to the second control module. The hydraulic parameter and / or another regulating signal is designed such that it predetermines and / or limits the dynamic behavior of the regulating mechanism of the hydraulic machine. The parameter is, for example, the maximum gradient or maximum rate of change of the actual outlet pressure and / or the actual delivery volume and / or the actual power and / or the actual torque.

[0013] The advantage of this solution is that the dynamic behavior of the hydraulic machine can be adjusted in a simple manner by means of the pressure medium supply assembly. The dynamic behavior is then set by means of the hydraulic parameter and / or by another regulating signal. It is thus advantageous that, for the user or the machine manufacturer, the usual damping measures of hydraulic machines can be simply configured and parameterized in the dynamic behavior limitation of the control device of the hydraulic machine.

[0014] The system characteristics of the pressure medium supply assembly, in particular the vibration characteristics, the control characteristics, the driver impression when used in a mobile working machine, change decisively with the dynamic behavior of the hydraulic machine. Since this can be clearly predetermined and set by means of the hydraulic parameter and / or by another regulating signal, the characteristics of the entire pressure medium supply assembly can, for example, be better and can be better matched.

[0015] Advantageously, the maximum gradient or maximum rate of change of one or more actual parameters of the pressure medium supply assembly is set as a parameter. Thereby, the dynamic characteristics of the pressure medium supply assembly can be directly influenced by taking into account the gradient of one or more actual parameters in the control device. For example, the maximum delivery volume adjustment speed or the delivery volume adjustment speed preset value of the actual delivery volume for a hydraulic press is set as a parameter. Alternatively or additionally, it can be considered to use the maximum pressure gradient of the actual output pressure for a hydraulic press as a parameter. Furthermore, as an alternative or in addition, the nominal differential pressure can be set as a parameter and / or one or more nominal torques and / or the maximum gradient of the actual torque of the hydraulic press can be set as a parameter.

[0016] In another design of the present invention, instead of or in addition to the nominal output pressure and / or the nominal delivery volume, as an adjustment signal or input parameter for the second control module, a nominal torque can be fed via a data interface, in particular from the first control module. Thereby, the hydraulic press can also be controlled in a simple manner according to the nominal torque and / or the nominal power.

[0017] In another design of the present invention, at least one hydraulic parameter or a part or all of the parameters are adjustable as previously described in order to influence the dynamic characteristics, for example, also during the operation of the pressure medium supply assembly. The adaptation of one or more parameters is preferably carried out according to the state parameters of the pressure medium supply assembly and / or according to the preset values of the operator. For example, the temperature of the pressure medium can be regarded as a state parameter. Here, it can be, for example, the pressure medium on the output side or at the output of the hydraulic press. Alternatively or additionally, it can be stipulated that the setting or adaptation is carried out according to the actual rotational speed of the hydraulic press or according to the actual output pressure of the hydraulic press and / or according to the actual delivery volume of the hydraulic press and / or the actual swing angle. By adjusting one or more parameters based on one or more actual parameters, the dynamic characteristics of the pressure medium supply assembly can be matched with high precision in a simple manner.

[0018] Furthermore, it is advantageous that at least one hydraulic parameter can be used to match the dynamic characteristics on the one hand and, for example, also the rated parameters for controlling the hydraulic press on the other hand. This is achieved, for example, based on the operating point of the hydraulic press, i.e., for example, based on the actual volume flow or the actual output pressure. Alternatively or additionally, this can also depend on the load of the load and / or the rated parameters, such as, for example, the pressure gradient, the load pressure, or the angle gradient, in order to reduce vibrations and improve the movement quality. The determination of these states is preferably achieved by an electronic means. In summary, an improved efficiency can be achieved by the hydraulic pressure medium supply assembly according to the present invention. In addition, a simpler integration into mobile work machines, for example, can be achieved and fewer components are required compared to the prior art. In other words, it is particularly advantageous to match the dynamic characteristics of the hydraulic press with the corresponding operating states in order to generally achieve the maximum dynamic characteristics with maximum stability. The dynamic characteristics of the hydraulic press can be electronically controlled by at least one hydraulic parameter. For this reason, components such as, for example, damping nozzles or damping hoses, valves for overshooting, or hydraulic mechanical elements in the system, such as, for example, the pressure distribution line in a rotary mechanism, are no longer required to influence the dynamic characteristics.

[0019] In a preferred design of the present invention, the one or more parameters can be adjusted according to one or more loads controlled by the hydraulic pressure medium supply assembly. In particular, the adjustment is based on one or more moving loads. Therefore, the dynamic characteristics can be better influenced by using at least one parameter.

[0020] Preferably, the parameter in the form of the maximum pressure gradient is related to the actual rotational speed of the drive unit driving the hydraulic press and / or to the torque gradient of the actual torque available for the drive unit driving the hydraulic press. The drive unit refers, for example, to an internal combustion engine, especially a diesel engine, or to an electric motor.

[0021] Preferably, the parameter in the form of the maximum rated differential pressure is matched as follows, i.e., the maximum rated differential pressure is set during normal operation and / or a particularly small maximum rated differential pressure is set in the fine control range of the load and / or a particularly large maximum rated differential pressure is set in the erosive or rapid or rough control range of the load. Alternatively or additionally, it can be considered to match the parameter in the form of the rated differential pressure according to the type of the internal combustion engine, such as the type of a diesel engine, and / or according to the available actual torque of the drive unit. Alternatively or additionally, it can be considered to match the parameter in the form of the rated differential pressure according to "Bucket Shake" and / or according to the travel operation of the mobile working machine with a pressure medium supply assembly. That is, for example, the matching is only performed when the travel of the mobile working machine is detected. In the case of Bucket Shake, the joystick for the bucket cylinder moves quickly back and forth to shake the material out of the bucket. The pump dynamic characteristics should be particularly high here to be able to shake the bucket well.

[0022] In another design of the present invention, the parameter in the form of the maximum rated torque and / or in the form of the maximum rated differential pressure is matched according to the battery charge state of the battery of the drive unit for the hydraulic press in the form of an electric machine, especially in the form of an electric motor. Alternatively or additionally, it can be specified to match the maximum rated torque according to the type of the electric machine and / or according to the temperature of the battery.

[0023] Preferably, the parameter in the form of the maximum pressure gradient and / or in the form of the maximum delivery volume adjustment speed is related to one or more loads controlled by the hydraulic pressure medium supply assembly.

[0024] By means of the parameter in the form of the maximum differential pressure or the rated differential pressure or the pressure gradient, for example, the speed control of the mobile working machine can be performed when the mobile working machine equipped with the pressure medium supply assembly travels. The mobile working machine is driven here, for example, by a hydraulic drive device supplied by the pressure medium supply assembly. Therefore, it is possible to easily achieve travel in an open-loop hydraulic circuit with speed limitation.

[0025] It can also be considered to match the parameter in the form of the maximum pressure gradient or the maximum torque or the maximum gradient of the actual torque according to the diesel extrusion and / or the rotational speed disturbance of the diesel engine.

[0026] In another design of the present invention, the parameter in the form of the maximum delivery volume can be related to the operator's expectation, i.e., it can be adjusted by the operator, for example. Thus, it is possible to simply limit the maximum speed of the movement of one or more loads according to the expectation.

[0027] Preferably, one or more loads in the form of hydraulic cylinders are provided. The hydraulic cylinder may here, for example, have a piston which is connected to a piston rod and delimits at least one pressure chamber. The dynamic characteristics of the load can be controlled by means of the pressure medium supply assembly according to the invention, in particular the actual pressure gradient can be controlled by means of the limitation of the pump. It may be considered, for example, that the piston is braked by means of a control device in the direction of the reduction of the pressure chamber, in particular at the end of its movement displacement, in order to avoid hitting the cylinder housing or at least to reduce the impact speed. Thereby large pressure peaks can be avoided. This can be referred to as electronic end position damping. In contrast, in the prior art, costly device-technical measures are required for this purpose.

[0028] In a further design variant of the invention, it may be considered to match the pump dynamic characteristics or parameters to the operating function of the mobile working machine. If the mobile working machine is used, for example, as an excavator for power excavation in the form of an excavator, the mobile working machine has different pump dynamic characteristics than during operating work.

[0029] Advantageously, the vibration of the pressure medium supply assembly can be detected and / or calculated by means of a corresponding device, and then one or more parameters are matched according to this vibration.

[0030] In a preferred solution, it may be considered to match one or more parameters according to a stored control section model. The control section model is, for example, the control section of a mobile working machine having a pressure medium supply assembly. In the control section, for example, the type of the mobile working machine can be considered, such as the type of an excavator, its kinematics, the hydraulic capacity of the hydraulic components, the inertia of the load, the transmission ratio, etc. It may be considered to provide different control section models for different hardware configurations.

[0031] In a preferred embodiment of the invention, the matching of a parameter, in particular in the form of the maximum rated output pressure, can be related to the deflection of one or more operating elements, such as a joystick. Thereby a force feeling for the operator can be achieved in a simple manner. In the case of small operating preset values, for example, the movement of the load only starts when the load pressure is below an upper limit associated with the operating element.

[0032] In a further design variant of the invention, it may be considered that different operating modes can be set. In the respective operating mode, at least one preset parameter and / or a preset adjustment signal for the adjustment of the dynamic characteristics of the hydraulic press can be set. Then, these operating modes can differ from each other in terms of the value of at least one of their parameters and / or in terms of the value of at least one of their adjustment signals. Thereby different operating modes can be set, for example, a dynamic characteristics mode or a fine control mode, in which different parameters are preset with respect to the dynamic characteristics of the hydraulic press.

[0033] As a running mode, it can be stipulated, for example, that the matching of especially the maximum pressure gradient and / or especially the maximum swing angle gradient and / or especially the maximum angular gradient is carried out according to the moving load. Alternatively or additionally, as a running mode, it can be stipulated that the matching of the maximum pressure and / or the maximum rated output pressure or the maximum actual output pressure is carried out according to the deflection of one or more operating elements, such as one or more joysticks. Alternatively or additionally, as a running mode, it can be stipulated that when a specific running or operating situation is detected, the running mode carries out the matching of parameters. For example, when barrel shaking is detected, the matching of the parameter delta p or the rated differential pressure is carried out. As an alternative or supplement, as a running mode, it can be stipulated that the matching of the torque limit and / or the maximum rated torque and / or the maximum actual torque is carried out according to the operating state of the electric drive device, such as battery charge and / or motor temperature and / or battery temperature. The electric drive device is, for example, part of the mobile working machines listed below.

[0034] Preferably, the adjusting mechanism has an adjusting cylinder and an electro-proportionally controllable pilot valve. The adjusting cylinder has an adjusting piston for adjusting the delivery volume of the hydraulic press. By means of the pilot valve, the inflow and / or outflow in the control chamber of the adjusting cylinder defined by the adjusting piston can be controlled, for example. Thereby, the adjusting piston can be loaded with pressure medium for actuation.

[0035] In another design of the present invention, at least one filter for at least one input parameter or a corresponding filter for a part of the input parameters or for all input parameters can be provided in the second control module. Preferably, the filtered input parameter, or a part of the partially filtered input parameters, or all of the filtered input parameters can be transmitted to the first control module. Thus, filtered and stable actual parameters can be output to the superior control device or the first control module.

[0036] Preferably, the adjustment parameter for the pilot valve is set as the output parameter of the second control module. It can be considered that the second control module has a first control loop for the actual output pressure of the hydraulic press. The first control loop is preferably tapped between the high-pressure connection of the hydraulic press and the control block. Alternatively or additionally, the first control loop can be provided for the actual delivery volume of the hydraulic press.

[0037] If the hydraulic press is an axial piston machine having an adjustable swashplate or swash drum for setting the delivery volume, then the actual delivery volume can be detected, for example, by corresponding devices, such as by a swivel angle sensor, like a displacement sensor for adjusting the piston. As an alternative to the displacement sensor, the swivel angle of the swashplate on the swivel axis can also be measured by a Hall sensor. In other words, there is a measuring device for detecting the displacement position or displacement volume. It is also possible to consider determining the swivel angle via the torque of the drive shaft or via pressure measurement. Preferably, the second control loop is subordinate to the first control loop, and the second control loop can be provided for the delivery volume adjustment speed. The actual delivery volume adjustment speed of the hydraulic press, in particular as the derivative of the actual delivery volume, is preferably set as the input parameter for the second control loop. If the actual delivery volume adjustment speed is determined from the actual delivery volume, the detected actual delivery volume can advantageously be used not only for the first control loop but also for the second control loop, so that there is no need to separately detect the actual delivery volume adjustment speed. The output parameter of the second control loop is preferably the adjustment parameter for the pilot valve. Advantageously, the adjustment value in the form of the delivery volume adjustment speed from the first control loop can be fed to the second control loop. The adjustment value from the first control loop can then be the setpoint parameter for the second control loop.

[0038] Furthermore, the first control loop of the control device can be configured for the actual torque of the hydraulic press. Then, for example, the setpoint torque and the actual torque are set as the input parameters for the control device. Alternatively or additionally, it can be considered that the first control loop of the control device is configured for the actual power taking into account the actual rotational speed of the hydraulic press. It is also possible to consider determining the actual power or the actual torque from the actual rotational speed via a characteristic curve in order to then control the actual power. For controlling the actual torque, a controller, in particular a P-controller, can be provided. Alternatively, it can be considered that the controller is configured as a PI controller or a PID controller.

[0039] In another design of the present invention, the first control loop has an adjustment parameter for the actual output pressure of the hydraulic press and / or for the actual delivery volume of the hydraulic press and / or for the actual torque of the hydraulic press, respectively. Then, the control device can provide a separate control having a minimum value generator for the output adjustment parameters of the first control loop. The output parameter of the minimum value generator is preferably an adjustment value in the form of the delivery volume adjustment speed, and this adjustment value is fed to the second control loop. The minimum value generator ensures that only the controllers assigned to the desired operating points are automatically activated. For example, the minimum value generator selects the smallest adjustment parameter among the fed adjustment parameters and then feeds this adjustment parameter as the setpoint delivery volume adjustment speed to the subordinate second control loop.

[0040] For the delivery volume of the hydraulic press or the swing angle by which the delivery volume can be determined, the first control loop preferably has a controller. The controller is preferably, for example, a P-controller. Alternatively, the controller can be configured as a PI controller or a PID controller. The controller can have a nominal swing angle and an actual swing angle or a nominal delivery volume or an actual delivery volume as input parameters.

[0041] Preferably, a filter, for example in the form of a PT1 element or a higher-order filter, is provided for the actual swing angle. Signal stabilization can be achieved in a simple manner by means of the filter.

[0042] Preferably, the first control loop has a controller for the actual output pressure of the hydraulic press. As input parameters, in particular the actual output pressure detected by means of a pressure sensor and the nominal output pressure are fed to the first control loop. Preferably, a PID controller is provided as the controller. Alternatively, a P-controller or a PI-controller can be used. The nominal output pressure of the hydraulic press is preferably adjustable. In particular, in order to determine the nominal output pressure, the actual load sensing (LS) pressure of the load supplied with pressure medium via the pressure medium supply assembly is detected. In particular, the actual LS pressure is the highest actual load pressure of the load. Preferably, the actual LS pressure is fed as an input parameter to the control device or to the controller for the actual output pressure. In the load sensing (LS) control device, the highest load pressure of the regulating pump should be notified and the regulating pump should be controlled in such a way that an actual output pressure higher than the highest actual load pressure by a specific pressure difference (delta_p) exists in the pump line. It is therefore advantageously provided that the nominal differential pressure is additionally fed as an input parameter to the controller for the actual output pressure. The nominal output pressure can then be calculated by adding the actual LS pressure and the nominal differential pressure and used as an input parameter for the controller. The nominal differential pressure can be parameterized fixedly or flexibly adjustable and pre-given as a parameter.

[0043] In particular, it is also possible to consider detecting a plurality of actual LS pressures and performing maximum value formation or priority determination in the control device. This can be achieved by feedback to the main valve or the main control valve, for example when the delivery volume of the hydraulic press (pump) is limited and thus the delivery volume guided through the main valve can be restricted, whereby, for example, priority determination for hydraulic steering can be achieved in the case of insufficient supply. Here, in addition to LS pressure control, the hydraulic press (pump) is advantageously set to the minimum amount in order to ensure steering ability even in the case of incorrect information from the pressure sensor.

[0044] In a controller for actual output pressure and / or for actual delivery volume and / or for actual torque, an I component can be provided, as in a PID controller, for example, which was described above. Then, especially when using a minimum value generator, it can be provided that in one or more controllers that are deactivated and have an I component, the I component is frozen or especially partially or completely reset. If the controller is subsequently activated, the I component is used in the normal way. This results in the I component of one or more controllers not being increased (aufziehen) when deactivated. This design can be referred to as "anti-windup".

[0045] For a controller for actual output pressure, one or more filters with pressure-dependent filter coefficients can advantageously be provided. A corresponding filter is, for example, a variable PT1 filter or a higher-order filter. Preferably, the filter or the corresponding filter arrangement is for actual output pressure and / or for actual LS pressure. The pressure-dependent filter is preferably designed such that the filtering is reduced when the actual output pressure of the hydraulic press increases and, conversely, the filtering is increased when the actual output pressure of the hydraulic press decreases, in order to influence the dynamics of the control.

[0046] Alternatively or additionally, one or more filters, especially with pressure-dependent filter coefficients, can be used for the other controllers listed above and below, especially for one or more input parameters.

[0047] Alternatively or additionally, it can be considered that for a controller for actual output pressure and / or for one or more of the controllers listed above and below, especially for one or more input parameters, an asymmetric filter is provided. This depends on the direction of swashplate oscillation. That is, the filtering of the filter in the first oscillation direction is different from the filtering in the second oscillation direction.

[0048] In another design variant of the invention, a gain factor (Kp) is provided, in particular for a regulator for the actual output pressure, which is related to the actual temperature of the pressure medium of the hydraulic press, in particular of the pressure medium on the output side, and / or to the actual rotational speed of the hydraulic press and / or to the actual output pressure of the hydraulic press and / or in particular to a predefined pressure gradient or nominal pressure gradient for the nominal output pressure of the hydraulic press. Thus, the gain factor can be determined based on these parameters. Then, for example, in the regulator, the gain factor can be multiplied by the regulation deviation, where the regulation deviation is, for example, the nominal LS pressure minus the actual LS pressure and / or, for example, the nominal output pressure minus the actual output pressure. It is preferably provided that the lower the actual temperature, the lower the gain factor, since in this way it is preferably possible to prevent or at least reduce the vibrations of the hydraulic press in the cold state of the hydraulic press. Correspondingly, vice versa, it can also apply that the higher the actual temperature, the higher the gain factor. Alternatively or additionally, it can be provided that the lower the actual rotational speed of the hydraulic press, the higher the gain factor, since the pressure build-up depends on the volume flow and thus on the rotational speed of the hydraulic press. Correspondingly, vice versa, it can also apply here that the higher the actual rotational speed, the lower the gain factor. Alternatively or additionally, it can be provided that the greater the pressure gradient of the nominal output pressure, the higher the gain factor. This is advantageous because the greater the pressure gradient, the greater the requirements for positioning the hydraulic press and thus the hydraulic press must react faster than in the small-signal range. Vice versa, it can also apply here that the smaller the pressure gradient, the lower the gain factor. Alternatively or additionally, it can be provided that the higher the actual output pressure, the higher the gain factor. This is advantageous because at a higher actual output pressure, the control section dynamics (Streckendynamik) are also higher. Thereby, the hydraulic press can oscillate faster without becoming unstable. Vice versa, the same relationship applies.

[0049] The gain factor can advantageously be designed as a regulation parameter depending on the operating point. For pressure regulation and / or for torque regulation and / or for swing angle regulation, it can apply that: the higher the actual output pressure, the higher the gain factor or the gain factor increases up to a predefined actual output pressure and then decreases again when the actual output pressure further increases. In other words, a gain factor can also be provided in the regulator for the actual output pressure and / or for the actual torque, in particular a gain factor for the actual parameters. In other words, in particular, a pressure-dependent adaptation of the regulation loop amplification can be provided. Thus, the regulation parameters are adaptable during the operation of the pressure medium supply assembly. Advantageously, a demand-based adaptation of the regulation dynamics is carried out during operation.

[0050] In another design variant of the invention, it can be provided that a nominal pressure gradient or a maximum nominal pressure gradient is set for the regulator of the actual output pressure. The nominal pressure gradient is preferably adjustable and adaptable. Then, the nominal pressure gradient can, for example, have an influence on the nominal output pressure. For example, the influence is such that the higher the nominal pressure gradient, the faster the hydraulic press should swing out. The higher the nominal pressure gradient, the faster an increase compared to the actual gradient is required, so that the hydraulic press swings faster in order to reach the nominal pressure gradient. It can be considered to use the nominal pressure gradient as a limit for the nominal output pressure or as a limit for the change in the nominal output pressure.

[0051] In another design variant of the invention, the first control loop preferably has a regulator for the actual torque or the actual power, which is based on the product of the actual torque and the actual speed. The actual speed can be set as an input parameter, which is measured by the transmission shaft of the hydraulic press, in particular by a speed sensor. Then, the actual torque or the absorbed torque of the hydraulic press (pump) can be calculated from the actual speed. The actual torque is calculated by multiplying the actual swing angle by the actual output pressure and dividing by the hydro-mechanical efficiency. The hydro-mechanical efficiency is a function of the actual output pressure, the actual swing angle, and the actual speed and can be determined, for example, by a characteristic curve. In addition, a nominal torque can be specified for the regulator. The regulating parameter on the output side of the regulator is preferably fed to a minimum value generator. The characteristic curve for determining the actual torque depends, for example, on the actual pressure and / or the actual swing angle. In other words, the instantaneous power can be calculated by the regulator, especially when the actual speed is also taken into account.

[0052] In another design variant of the invention, the actual parameters or a part of the actual parameters and one or more derivatives thereof for the first and second control loops are filtered in order to stabilize the signals. Here, for example, as described above, PT1 elements or variable PT1 elements are used.

[0053] As described above, it can be considered to specify a delivery volume adjustment speed preset value or a maximum delivery volume adjustment speed for the second control module, and the delivery volume adjustment speed preset value or the maximum delivery volume adjustment speed can especially be fed to the second control loop downstream of the minimum value generator. In particular, the maximum delivery volume adjustment speed is fed to the control device by means of a control element. This control element preferably has the adjustment value from the first control loop as an input parameter, i.e., the adjustment value output by the minimum value generator. The delivery volume adjustment speed preset value can be set as another input parameter. Then, the final rated delivery volume adjustment speed for the second control loop can be set as the output parameter of the control element. By means of an additional pre-given, for example adjustable, delivery volume adjustment speed preset value, the adjustment value of the minimum value generator is especially restricted in order to influence the control dynamics of the pressure medium supply assembly. The delivery volume adjustment speed preset value can for example be the positive or negative maximum value of the delivery volume adjustment speed. The higher the final rated delivery volume adjustment speed, the faster the hydraulic press can be swung out.

[0054] With the adjustable maximum rated pressure gradient and / or the adjustable delivery volume adjustment speed preset value explained above, the control dynamics of the pressure medium supply assembly can be influenced in a simple manner. Thus, the control force for the pilot valve can depend on the rated pressure gradient and / or the delivery volume adjustment speed preset value. These values can be variably matched during operation. Thus, a demand-based matching of the control dynamics can be carried out during operation and is for example related to the operating point or the working point. Thus, the pump dynamics can be restricted and / or matched by means of one or more values. The swing angle and / or the delivery volume adjustment speed of the hydraulic press can then be controlled in such a way that one or more rated values are not exceeded. In other words, with the adjustable parameters (especially the maximum rated pressure gradient and / or especially the adjustable delivery volume adjustment speed preset value), the dynamics of the pressure medium supply assembly can be matched by software parameters, whereby for example a soft or hard machine characteristic can be set. For sub-functions, the dynamics can also be changed. One sub-function can be matched to the rated pressure gradient and another sub-function can be matched to the delivery volume adjustment speed preset value. By matching the dynamics, a reduction in vibration can also be achieved. In addition, sudden movements can be avoided. It has been shown that the hydraulic pressure medium supply assembly especially leads to an increase in efficiency through less control oil consumption.

[0055] In other words, a method is disclosed which is provided for controlling the displacement and / or torque and / or pressure of a hydrostatic press.

[0056] The hydrostatic press can have an adjustment device for setting its displacement. Preferably, the method has the following steps:

[0057] - Detect a preset rated torque,

[0058] - Detect a preset rated displacement,

[0059] - Detect a preset rated pressure,

[0060] - Detect the actual displacement or the set displacement,

[0061] - Detect the actual pressure or the set pressure,

[0062] - Determine the actual torque or the set torque on the transmission shaft of the machine.

[0063] As a next step, it can be provided that the volume flow entering or leaving the regulating device is regulated by means of a regulating valve in order to set the displacement based on the force difference between the control force and the force acting on the regulating valve in the opposite direction. The force acting on the regulating valve in the direction opposite to the control force can be a spring force. The control force can also be the electrical force of an electromagnetic valve. The machine is set according to the detected displacement and / or pressure and / or rated displacement and / or rated pressure and / or rated torque. The displacement is preferably set in such a way that the smallest displacement is always set, which results in reaching one of the rated parameters.

[0064] As mentioned at the beginning, the volume flow of a hydraulic press or a regulating pump can be determined from the swing angle of the swashplate. If the regulating pump is not driven and the regulating system is pressureless, the regulating pump swings, for example, to the maximum delivery volume by the spring force of a spring. Conversely, in the driven state of the regulating pump and with the pilot valve de-energized and the pump outlet closed, the regulating pump swings to the zero-stroke pressure. The balance between the pump pressure on the regulating piston and the spring force of the spring occurs at approximately 4 to 8 bar. The basic setting is usually used in a voltage-less regulating electronics. Conversely, it is also conceivable that in a de-energized pilot valve, the regulating pump swings to the maximum delivery volume in order to ensure the supply of pressure medium to a load, such as a steering device. Preferably, a pressure limiting valve is then provided in order to limit the actual output pressure of the hydraulic press.

[0065] The pressure medium supply assembly is preferably used for mobile working machines which have a load sensing (LS) or LUDV regulating system. These mobile working machines can have, for example in the form of an adjustable axial piston machine, a torque limitation and / or an angle limitation of the swing angle of the hydraulic press. As mobile working machines, for example, a compact mini-excavator or a wheel loader is provided.

[0066] The pressure medium supply assembly using hydraulics can achieve dynamic and simultaneous parallel regulation of main process parameters, such as actual pressure, actual differential pressure, actual torque, and / or actual swing angle. This results in extremely flexible use in almost all open hydraulic circuits and, in further comparison with the solutions to date, especially also the possibility of influencing the hydraulic system during operation. When operating on mobile working machines, for example, for different load conditions and / or for different drivers, the dynamic characteristics can be matched as needed by parameters via a data interface or a software interface. To set the dynamic characteristics, different from the prior art, a damping nozzle and / or a hydraulic device for manipulating the LS signal are not required, thereby avoiding or at least minimizing the loss of control oil. This leads to an efficiency increase. In addition, it is possible to simply integrate the pressure medium supply assembly using hydraulics into the mobile working machine. For example, the hydraulic hose connection or pipeline will be removed from the hydraulic press, and for example, the LS pipeline is no longer required, thereby reducing costs.

[0067] Sensors can be provided to measure the actual parameters. Here, for example, one or more sensors can be provided to measure one or more load pressures of one or more loads. It is also possible to consider using a sensor for the actual output pressure. As another sensor, a sensor for the actual rotational speed of the hydraulic press can be provided. It is also possible to consider using a sensor for measuring temperature.

[0068] Preferably, the mobile working machine is provided with a pressure medium supply assembly using hydraulics. Description of the Drawings

[0069] The preferred embodiments of the present invention will be explained in detail below with the aid of schematic drawings. Shown therein are:

[0070] Figure 1 A pressure medium supply assembly using hydraulics according to the first embodiment is shown schematically,

[0071] Figure 2 Shown schematically for Figure 1 the second control module of the pressure medium supply assembly in

[0072] Figure 3 Shown schematically for Figure 1 the second control module of the pressure medium supply assembly in

[0073] Figure 4 A pressure medium supply assembly for a mobile working machine according to the first embodiment is shown schematically,

[0074] Figure 5 A pressure medium supply assembly for a mobile working machine according to another embodiment is shown schematically. Detailed implementation manner

[0075] According to Figure 1 A pressure medium supply assembly 1 for hydraulics is shown, which has a hydraulic machine in the form of an axial piston machine 2. The hydraulic machine has a swashplate for adjusting the delivery volume. The axial piston machine 2 can be used not only as a pump but also as a motor. The axial piston machine 2 is driven by a drive unit 4, which can be, for example, an internal combustion engine, such as a diesel unit, or can be an electric motor. The axial piston machine 2 is connected to the drive unit 4 via a transmission shaft 6. The rotational speed 8 of the transmission shaft 6 can be measured by a device (not shown), such as a rotational speed sensor, and fed to the control device of the pressure medium supply assembly 1. An adjusting mechanism 12 is provided for the axial piston machine 2. The adjusting mechanism has a pilot valve 14. The spool of the pilot valve can be controlled electro-proportionally by an actuator 16. For this purpose, an adjustment parameter 18 is fed from a second control module 20 to the actuator 16. The spool of the pilot valve 14 is loaded in the direction of the basic position with the spring force of a valve spring 22. Here, the spring force acts contrary to the actuator force of the actuator 16.

[0076] The axial piston machine 2 is connected on the output side to the pressure line 24, which in turn is connected to the main control valve 26 or the valve block. The pressure medium supply between the axial piston machine 2 and one or more loads can be controlled via this main control valve. A control line 28 branches off from the pressure line 24 and is connected to the pressure connection P of the pilot valve 14. Here, the internal supply of the axial piston machine 2 can be ensured by means of a corresponding configuration. The control line 28 is, for example, configured in the housing of the axial piston machine 2. In addition, the pilot valve 14 has a reservoir connection T, which is connected to the reservoir via a reservoir line 30. In addition, the pilot valve 14 has a working connection A, which is connected to the control chamber 32 of the adjusting cylinder 34. The control chamber 32 is delimited here by the adjusting piston 36 of the adjusting cylinder. The swashplate of the axial piston machine 2 can then be adjusted by means of the adjusting piston 36. The movement displacement of the adjusting piston 36 is detected by a displacement sensor 38. Alternatively or additionally, the swing angle of the rocking cradle of the axial piston machine 2 is measured by a rotary magnetic sensor from the swing axis of the rocking cradle. The actual delivery volume or actual displacement of the axial piston machine 2 can then be determined from the detected displacement. The actual delivery volume 40 is then reported to the control device 20. In the basic position of the spool of the pilot valve 14, the pressure connection P is connected to the working connection A and the reservoir connection T is blocked. When the spool is loaded with the actuator force of the actuator 16, the spool moves from its basic position in the direction of the switching position, in which the pressure connection P is closed off and the working connection A is connected to the reservoir connection T. Thereby, the adjusting piston 36 is loaded with the pressure medium from the pressure line 24 in the basic position of the spool of the pilot valve 14. In addition, a cylinder 42 is provided in the adjusting mechanism 12. The cylinder has an adjusting piston 44, which acts on the swashplate of the axial piston machine 2. The adjusting piston 44 delimits a control chamber 46, which is connected to the pressure line 24. The adjusting piston 44 is loaded by the pressure medium in the control chamber 46 and by the spring force of the spring 48 in such a way that the adjusting piston loads the swashplate in the direction of increasing delivery volume.

[0077] In addition, a pressure sensor 50 is provided, via which the pressure in the pressure line 24 is measured and reported to the second control module 20, where this pressure is the actual output pressure 52. In addition, a pressure sensor 54 is provided, which detects the highest actual load pressure (actual LS pressure) 56 transmitted to the second control module 20.

[0078] The first control module 57 is connected to the second control module 20 via a CAN interface 58 in order to transmit in particular the actual speed 8 to the second control module 20. It is also conceivable to feed the actual speed 8 directly to the second control module 20.

[0079] In the case of using the pressure medium supply assembly 1, the position of the swash plate of the axial piston machine 2 is controlled by the pilot valve 14 and the regulating piston 36. The delivered volume flow of the axial piston machine 2 is proportional to the position of the swash plate. The regulating piston 44 or the mating piston preloaded by the spring 48 is continuously loaded with the actual output pressure or the pump pressure. When the axial piston machine 2 is not rotating and the regulating mechanism 12 is without pressure, the swash plate is held in the +100% position by the spring 48. When the axial piston machine 2 is driven and the actuator 16 of the pilot valve 14 has no current, the swash plate swings to the zero-stroke pressure because the regulating piston 36 is loaded with the pressure medium in the pressure line 24. The balance between the actual output pressure on the regulating piston 36 and the spring force of the spring 48 occurs at a predetermined pressure or pressure range, for example, between 8 and 12 bar. This zero-stroke operation is used, for example, in a voltage-free electronic device or a voltage-free second control module 20. The control of the pilot valve 14 is achieved by the second control module 20, which is preferably a digital electronic device, alternatively an analog electronic device. The second control module 20 processes the required control signals, which will be further elaborated below.

[0080] Via the data interface 58, the first control module 57 can feed, for example, the rated delivery volume 70 or the rated swing angle or the maximum rated pressure gradient 102 and / or the rated pressure difference 100 and / or the rated torque 116 and / or the maximum rated delivery volume adjustment speed 130 and / or the rated output pressure 74 to the second control module 20. It is also conceivable that the second control module 20 feeds the actual delivery volume 40 or the actual swing angle and / or the actual LS pressure 56 and / or the actual output pressure 52 and / or the actual torque 124 to the first control module 57. The parameters 40, 56, 52 and / or 124 are preferably filtered here.

[0081] Figure 2 The mode of operation of the second control module 20 is schematically shown. The second control module has a first control loop 60 and a second control loop 62. The first control loop 60 has for Figure 1A controller 64 for the swivel angle of the swashplate of the axial piston machine 2, a controller 66 for the output pressure of the axial piston machine 2, and a controller 68 for the torque of the axial piston machine 2. The controller 64 has a rated delivery volume 70 and an actual delivery volume 40 as input parameters. An adjustment parameter 72 is set as the output parameter. The controller 66 has a rated output pressure 74 and an actual output pressure 52 as input parameters. An adjustment parameter 75 is set as the output parameter. The controller 68 has an actual torque 76 or a rated torque as an input parameter. The actual torque is set as the other input parameter, and this actual torque can be obtained via a characteristic curve family from the actual rotational speed 8, for example. An adjustment parameter 78 is set as the output parameter for the controller 68. In the respective controllers 64 to 68, the input parameters are fed to a control element in the form of a PID controller.

[0082] The adjustment parameters 72, 75, and 78 are fed to a minimum value generator 80. This ensures that only the controllers 72, 75, or 78 assigned to the desired operating point are automatically activated. Here, either the output pressure, the torque, or the delivery volume is precisely regulated, where the other two respective parameters are below a pre-given rated value. The output signal of the minimum value generator 80 is then a rated value in the form of a delivery volume adjustment speed or a rated delivery volume adjustment speed 82. These parameters are then input parameters for a second subordinate control loop 62. Another input parameter for the second control loop 62 is the derivative of the actual delivery volume 40, and thus this other input parameter refers to the actual delivery volume adjustment speed 84. The input parameters 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 control element then outputs an adjustment parameter 18 for Figure 1 the pilot valve 14 in

[0083] According to Figure 3 shows another embodiment of the second control module 20 for Figure 1 . The second control module has a controller 88 for the delivery volume of the axial piston machine 2 (also see Figure 1 ). In addition, a controller 90 for the output pressure of the axial piston machine 2 and a controller 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 subordinate to the first control loop for the delivery volume adjustment speed of the axial piston machine 2 is provided.

[0084] The controller 88 has a control element 98 in the form of a P element. The rated delivery volume 70 and the actual delivery volume 40 are set as input parameters. The actual delivery volume 40 is fed using the control element 98 through a filter in the form of a PT1 filter. On the output side of the controller 88, the adjustment parameter 72 is set as the output parameter fed to the minimum value generator 80.

[0085] The controller 90 has the actual output pressure 52, the actual LS pressure 56, the rated pressure difference 100, and the rated pressure gradient 102 as input parameters. The actual LS pressure 56 and the rated pressure difference 100 are combined into a rated output pressure by a summing element 104. The rated output pressure is then fed to a control element 106 in the form of an inverse PT1 element, which estimates the expected signal curve. The rated output pressure is then further fed to a control element 108, which has the rated pressure gradient 102 as another input parameter. Then, the rated pressure gradient 102 predefines the maximum possible gradient that should be set. Then, the rated output pressure is influenced by the predefined rated pressure gradient 102 by the control element 108 such that the dynamic characteristics of the pressure medium supply assembly 1 in Figure 1 can be controlled. For example, this influence can be such that the higher the rated pressure gradient 102, the faster the swashplate of the axial piston machine 2 can be adjusted. Conversely, it applies that the smaller the rated pressure gradient, the slower the swashplate of the axial piston machine 2 is adjusted. After the control element 108, the rated output pressure is then fed to a control element 110 in the form of a PID element. Then, the actual output pressure 52 is set as another input parameter for the control element 110. As the output parameter of the control element 110, an adjustment parameter 75 is obtained and fed to the minimum value generator 80.

[0086] The actual LS pressure 56 of the controller 90 is fed to a filter 112 before the summing element 104, and this filter is a variable PT1 filter. The same applies to the actual output pressure, which is also fed to a filter 114 in the form of a variable PT1 filter before the control element 110. The filters 112 and 114 have variable, especially pressure-dependent, filter coefficients, which were described in more detail above.

[0087] The controller 92 has the actual rotational speed 8, the actual delivery volume 40, the actual output pressure 52, and the rated torque 116 as input variables. These input variables are fed to the control element 118 in the form of a P element. The adjustment variable 78 is set as the output variable for the control element 118, and this adjustment variable is fed to the minimum value generator 80. After the control element 118, there is a control element 120 for the adjustment variable 78, which is a reverse PT1 filter like the control element 106. In addition, the actual rotational speed, the actual delivery volume 40, and the actual output pressure 8 are fed to the control element 122 before being fed to the control element 118. This control element calculates the actual torque 124 based on the actual rotational speed 8, the actual delivery volume 40, and the actual output pressure 8. This calculation is carried out with the aid of the characteristic curve family of the control element 122. The characteristic curve family depends on the actual output pressure 52 fed to the control element 122. In addition, the actual delivery volume 40 is fed to the control element 122. The characteristic curve family can then alternatively or additionally depend on the actual delivery volume 40. In other words, the actual torque 124 is formed by the actual rotational speed 8 and the actual output pressure 52 and / or by the actual delivery volume 40. Then, the actual torque 124 is fed to the filter 126 in the form of a PT1 element before it reaches the control element 118.

[0088] In addition, the actual delivery volume 40 is fed to the filter 99 in the form of a PT1 element before it is fed to the control element 98.

[0089] The minimum value generator 80 forms the rated delivery volume adjustment speed 82 from the adjustment variables 72, 75, and 78. This rated delivery volume adjustment speed is fed to the control element 128. With this control element, the dynamic behavior of the pressure medium supply unit 1 can be influenced. For this purpose, an adjustable rated delivery volume adjustment speed preset value 130 is set as another input variable for the control element 128. For example, with the rated delivery volume adjustment speed preset value 130, the rated delivery volume adjustment speed 82 output from the minimum value generator 80 can be limited and / or influenced in such a way that the greater the parameter 130, the faster the swashplate of the axial piston machine 2 can oscillate, and vice versa. Thus, the dynamic behavior of the pressure medium supply unit 1 can be influenced by the adjustment of the rated delivery volume adjustment speed preset value 130 and / or by the adjustment of the rated pressure gradient 102. For example, in this way, the pressure medium supply unit 1 can be matched to different working machines and / or different operating conditions and / or different purposes of use in a simple and cost-effective manner.

[0090] After the control element 128, the final setpoint delivery volume control speed 132 is fed as an input variable to the second control loop 96. The second control loop has a control element 134 in the form of a PI element. The actual delivery volume control 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 the control element 136. The derivative, i.e. the actual delivery volume control speed, is then fed to a filter 138 in the form of a PT1 filter. Before the actual variable 84 is fed to the control element 134, a control element 140 in the form of an inverted PT1 filter is then provided. The control element 134 of the second control loop 96 has a filter for Figure 1 The manipulated variable 18 of the pilot valve 14 in the summing element 142 is used as an output variable. This manipulated variable is fed to the summing element 142. A precontrol value 144 is provided as a further input variable for the summing element 142. This precontrol value is the output variable of the control element 150, which has the actual output pressure 52 as an input variable. The precontrol value 144 is then determined based on the actual output pressure 52. The summing element 142 then combines the manipulated variable 18 and the precontrol value 144 to thereby precontrol the neutral current of the pilot valve. This enables a pressure-dependent presetting of the neutral current for the Figure 1 The neutral signal value of the pilot valve 14 in . This has the advantage that the control device 20 is relieved of this control task. The final manipulated variable 146 for the pilot valve 14 is then provided as the output variable of the summing element 142 .

[0091] It can be considered that Figure 3 A control element (not shown) is connected downstream of the summing element 142, which has a control variable 146 as an input variable. This input variable is superimposed with the low-frequency signal by the control element, whereby the valve core of the pilot valve 14 is constantly in an axial oscillating motion to prevent the valve core from getting stuck. The final control variable for the pilot valve 14 is then specified as the output variable of the control element. The superposition with the low-frequency signal can be called "dithering".

[0092] according to Figure 3 , the actual delivery volume 40 is fed after the filter 99 as a filtered actual delivery volume 152 to Figure 1 In addition, the actual LS pressure after the filter 112 can be fed to the first control module 57 as the filtered actual LS pressure 154. Figure 1 After the filter 114 , the actual output pressure 52 may also be fed to the first control module 57 as a filtered actual output pressure 156 . In addition, the actual torque 124 after the filter 126 may be fed to the first control module 57 as a filtered actual torque 158 .

[0093] Figure 4 Shows a pressure medium supply assembly for a mobile working machine in the form of a telescopic manipulator. The pressure medium supply assembly has two axial piston machines 2 and 186, which are driven by a drive unit 4 in the form of a diesel engine set via a common transmission shaft. The pilot valves of the axial piston machines 2, 186 are controlled by a control device 20 as described above. The axial piston machine 186 is used to supply pressure medium to the wheel braking device 88, the steering system 190 and the pilot oil supply device 192. The pilot oil supply device 192 is provided for the main control valve 26 and the main control valve block. The pressure medium supply to the hydraulic cylinders 168, 170, 194, 196 is controlled by this main control valve block. In addition, the hydraulic press 198 and the hydraulic auxiliary motor 176 used are controlled by the main control valve 26. There is provided an input device 178 which is connected, for example, to the second control module 20 via a CAN bus 180. In addition, a communication device 200 is provided in order to perform communication with a server and / or with a computer wirelessly, for example via radio or WiFi. For example, then the input parameters for the second control module 20 can be matched and / or the software can be extended or updated via the communication device 200. In addition, data can be sent via the communication device 200, the data including information about the state of the pressure medium supply assembly 1.

[0094] The control modules 20 and 57 are arranged Figure 4 in a common housing. In the housing, there is provided a data interface through which parameters 70, 102, 100, 116, 130, 74, 40, 56, 52 and 124 can be transmitted.

[0095] According to Figure 5A pressure medium supply assembly for a compact excavator is shown. Here, an axial piston machine 2 can be seen, which is driven by a drive unit 4 in the form of a diesel engine unit. Furthermore, a second control module 20 is shown, which is connected, for example, to a pressure sensor 202 that measures the actual output pressure of the axial piston machine 2. In addition, the second control module 20 is connected to a pressure sensor 204 that measures the maximum load pressure via a main control valve 26 or a main control block. Furthermore, the second control module 20 is connected to a sensor 206 for the swivel angle of the swashplate of the axial piston machine 2. In addition, a pilot valve 14 is connected to the second control module 20. Five hydraulic cylinders 208 are connected to the main control valve 26. In addition, hydraulic presses 172, 174 and a hydraulic auxiliary motor 176 are connected. Optionally, a pilot oil supply device 192 can be provided. An input device 178 can hydraulically control, for example, the main control valve 26 or be connected to the pressure medium supply assembly via a CAN bus 180. In addition to the second control module 20, a first control module 57 is also shown. Thus, parameters 70, 102, 100, 116, 130, 74, 40, 56, 52 and / or 124 can be exchanged via a data interface in the form of a CAN bus.

Claims

1. A hydraulic pressure medium supply assembly having a hydraulic press (2) for supplying pressure medium to at least one hydraulic load (168, 170, 194, 196, 208), the hydraulic pressure medium supply assembly having a hydraulic control block (26) for controlling the at least one load (168, 170, 194, 196, 208), and the hydraulic pressure medium supply assembly having first and second control modules (20, 57), wherein the control block (26) can be controlled by at least one first adjustment signal via the first control module (57), wherein, A data interface (58) is provided between the control modules (20, 57), and wherein the first control module (57) is configured to transmit, as a second adjustment signal, the rated output pressure (74) for the hydraulic press (2, 186) and / or the rated delivery volume (70) for the hydraulic press (2, 186) as input parameters to the second control module (20) via the data interface (58), wherein the second control module (20) is configured to control the adjustment mechanism (12) of the hydraulic press (2) with a valve adjustment signal (18, 146) according to the rated output pressure (74) and / or according to the rated delivery volume (70), and wherein the hydraulic pressure medium supply assembly is configured to transmit at least one hydraulic parameter (70, 74, 100, 102, 116, 130) and / or another adjustment signal to the second control module (20) via the data interface (58), the hydraulic parameter or adjustment signal predefining and / or limiting the dynamic characteristics of the adjustment structure (12) of the hydraulic press (2), wherein the maximum delivery volume adjustment speed (130) of the hydraulic press (2) and / or the maximum pressure gradient (102) for the actual output pressure (52) of the hydraulic press (2) and / or the maximum rated differential pressure (100) for the hydraulic press (2) and / or the maximum torque gradient are set as parameters.

2. The pressure medium supply assembly according to claim 1, wherein, As an additional adjustment signal for the second control module (20), the rated torque (116) can be fed via the data interface (58).

3. The pressure medium supply assembly according to claim 1, wherein, One parameter or a part of the parameter or all the parameters can be set according to the temperature of the pressure medium and / or according to the actual rotational speed of the hydraulic press (2) and / or according to the actual output pressure (52) of the hydraulic press (2) and / or according to the actual delivery volume (40) of the hydraulic press (2).

4. The pressure medium supply assembly according to any one of claims 1 to 3, wherein, The matching of the maximum rated differential pressure (100) is carried out such that the maximum rated differential pressure (100) for the normal operation of the pressure medium supply assembly is set, and / or the maximum rated differential pressure for the fine control range of the load is set, and / or the maximum rated differential pressure is set within the coarse control range of the load.

5. The pressure medium supply assembly according to any one of claims 1 to 3, wherein, Different operating modes can be set, wherein the respective operating mode has at least one predefined parameter and / or a predefined adjustment signal for the dynamic characteristics of the adjustment of the hydraulic press (2), and wherein the operating modes are different from each other in terms of at least one parameter and / or in terms of at least one adjustment signal.

6. The pressure medium supply assembly according to claim 5, wherein, As an operating mode, the pressure gradient and / or the swing angle gradient can be matched according to the moving load, and / or wherein, as an operating mode, the maximum pressure can be matched according to the deflection of at least one operating element, and / or wherein, as an operating mode, the parameters can be matched when a specific operating or control situation is detected, and / or wherein, as an operating mode, the torque limit can be matched according to the operating state of the electric drive device.

7. The pressure medium supply assembly according to any one of claims 1 to 3, wherein, In the second control module (20), a filter (99, 112, 114, 126, 138) for at least one input parameter or a corresponding filter for a part of the input parameters or a filter for all input parameters is provided.

8. A mobile working machine having a pressure medium supply assembly according to any one of claims 1 to 7.

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