Pilot control device for at least one valve actuator of a hydraulic valve and method for operating the same

Description

[0001] The present invention relates to devices and methods for the safe and economical operation of hydraulic valves, even under harsh operating conditions. Hydraulic valves are used, among other things, in construction machinery, agricultural vehicles, and in mining. Especially in such applications, it is important that the hydraulic valves are highly robust against external influences, especially vibrations, and that the desired valve positions can be reliably adjusted in all operating situations.

[0002] Typical hydraulic valves for the above applications have a valve spool that is moved by a valve drive with a motor (also called an actuator). This allows the valve spool to be moved to different positions, allowing hydraulic lines to be (partially) opened or closed as needed. Such actuators and hydraulic valves are described, for example, in EP3 121 485 A1 or US 2008 / 0121830 A1.

[0003] The document WO 2004 / 016900 A1 and the document DE 10 2014 017 413 B3 each disclose approaches to outsourcing the parameterization of a valve drive of a hydraulic valve to other components (out of the valve drive), and from DE 10 2018 202 258 A1 approaches are known to provide an emergency control with emergency power supply for a hydraulic valve in the event of a power failure.

[0004] Such hydraulic valves are usually modular in design, so that different tasks are distributed across different modules. A so-called pilot control unit is connected to the actual valve actuator via electrical cables. A single pilot control unit can be configured to supply electrical power to multiple valve actuators. Each valve actuator can, for example, have a stepper motor, its power output stage, and electronics associated with the stepper motor.

[0005] Essentially, each individual valve and its valve actuator are individually configured and parameterized for the respective application. This can be explained using the example of a series of valves for operating an excavator arm. Each valve has specific specifications as to which volume flows and pressure it should provide for each valve position so that the hydraulics connected to this valve can perform its tasks in operating the excavator arm. For example, operating a double hydraulic cylinder to raise the excavator arm requires higher pressures and volume flows than a single cylinder to tilt the excavator bucket. To ensure that these specifications can be implemented, the individual configuration and parameterization takes place within the framework of the so-called application (the configuration of the individual valve for the respective application).Implementing certain specifications requires mechanical modifications / adjustments to the valve itself, for example, the valve spool. However, a wide range of specifications can also be achieved through pure parameterization in the valve actuator. This is achieved by storing corresponding data, particularly parameters, characteristic maps, etc., in the valve actuator.

[0006] Until now, it has been common practice for the electronics located in a valve actuator to also contain the entire parameterization of the valve actuator for the respective application and to perform control tasks. Calibration data / characteristic maps and the like are stored there, and control loops are implemented. Operating commands transmitted to the hydraulic valves by a higher-level control system (e.g., an excavator control unit) are implemented in the respective valve actuator. In this configuration, the pilot control unit only delivers commands in the form of data and receives feedback on the correct execution of the commands or on any faults. Typically, combined power and data lines are used for the power supply of the valve actuator and for communication between the pilot control unit and the valve actuator.

[0007] The pilot control unit has thus far been used purely as a support to create an error-free / fail-safe operating environment for the individual valves. Parameterization, along with other, possibly also mechanical, individualizing interventions on the valve itself, is treated as part of the valve itself or as belonging to the valve. This approach has always been considered suitable because parameterization represents an alternative approach to mechanical modification of the respective valve.

[0008] However, this division of tasks has several disadvantages. Since a specific valve actuator can be used for various valves, each requiring different parameterization and control, the electronics must be different for each individual application, or there must be a way to reprogram the electronics in each valve actuator. Even if the requirements of a given application change, intervention in the electronics is necessary. This places high demands on logistics and spare parts management. In addition, valve actuators are often subject to greater mechanical stress than pilot control devices, which can be located in more protected locations, so their electronics must be very robust and are more susceptible to failure.

[0009] The object of the present invention is to avoid or reduce these disadvantages and to realize an economically and technically advantageous distribution of tasks between the pilot control device and the valve drive.

[0010] These objects are achieved by a pilot control device according to independent claim 1 and the described method according to claim 8. Advantageous embodiments and / or further developments, to which the invention is not limited, are specified in the respective dependent claims. The invention also comprises a computer program product comprising commands that cause the described pilot control device, together with valve drives, to execute the described methods.

[0011] What is to be described here is a pilot control device for at least one valve drive of a hydraulic valve with a valve spool, wherein the valve spool can be adjusted by the valve drive in order to supply hydraulic lines through the hydraulic valve with hydraulic fluid, wherein the pilot control device is set up to supply electronics and a power output stage for actuating an electrical actuator of the valve drive with electrical energy and operating commands, wherein the pilot control device contains a controller for supplying the electronics with operating commands, in which controller a parameterization module is present for this purpose, in which operating parameters for the operation of the at least one hydraulic valve by its valve drive are stored.

[0012] With the parameterization module, some functions previously performed by the electronics in the valve actuator have been transferred from there to a pilot control unit, transforming the valve actuator into a fully functional pilot control unit. Figuratively speaking, the "intelligence" is shifted from the valve actuator to the pilot control unit, leaving a "dumb" electronics system with purely "administrative tasks" but no "control functions" in the valve actuator. Technically, this means that the pilot control unit stores the parameterizations for the valve actuators it supplies and also contains control loops and performs control tasks. The electronics in the valve actuator only receive data about when the actuator should perform certain movements / steps and transmits this data in an appropriate form to the actuator and its power output stage.The execution or any malfunction is reported to the pilot control unit, which then uses this information to control the valve actuator according to the respective parameterization and generates commands for the next movements / steps. In this way, a valve actuator can be used for different applications without modification or reprogramming, or it can be used in a given application for new requirements. Changes are made in the pilot control unit or are already stored there.

[0013] Since a pilot control unit is only connected to other components via electrical cables, it can be located in a protected, easily accessible location if necessary, although for safety reasons it is desirable to keep the connection paths to the valve controls as short as possible and to provide as few potential fault points as possible (deflection points, etc.). It is much easier to exchange memory data or reprogram in this location. Furthermore, an interface for such processes does not have to be provided on each valve actuator, but only one on the pilot control unit for a plurality of valve actuators. A powerful microprocessor can also be provided there, which contains the parameterization of many different applications and can take over the control of several valve actuators. This is more cost-effective than providing a microprocessor for control in each valve actuator.If wireless communication for updating or reprogramming is desired, this can be more easily implemented in just one pilot control unit than in numerous valve actuators.

[0014] Particularly preferably, the control system includes at least one control circuit for controlling the valve drive and a bidirectional data transmission to the valve drive.

[0015] The control loop is implemented on a microcontroller. From the control loop's perspective, the hydraulic valve is the controlled system. The control loop receives data about the operation of the hydraulic valve via a bidirectional data line between the hydraulic valve or its valve actuator or the electronics. This data can be, for example, electrical currents or forces occurring there, or information about the positions of the valve spool. This data can be considered controlled variables. It is used by the control loop, together with control data received from the pilot control unit, to calculate operating commands for the hydraulic valve or valve actuator, etc.

[0016] Bidirectional data transmission is, for example, the management of a bus system between the pilot control unit and the valve actuators, which provides a bidirectional data line via an actuator current line with which the valve actuators and the pilot control unit can communicate with each other.

[0017] The pilot control device has an electrical energy storage device and the electrical energy storage device is designed to move the valve spool from any possible valve spool position into a shut-off position by means of the valve drive and energy stored in the electrical energy storage device.

[0018] This electrical energy storage device is implemented by the dedicated control system in the pilot control unit or by a microprocessor with a data memory. The other functions of the pilot control unit described here can also be implemented by this control system.

[0019] According to the state of the art, it is common for the valve spool to be moved into a rest position by means of at least one return spring or held there when the drive is not active. This is described, for example, in EP 3 483 454 A1. This ensures the safe shutdown of such a hydraulic valve, especially in the event of a power failure. With a suitable integration of the hydraulic valve into the control of a controlled movement element (excavator bucket, tractor fork, etc.), safe operation of the controlled movement element can also be ensured by safely shutting off the hydraulic valve.

[0020] However, the described return spring also has disadvantages. On the one hand, it is an additional component that increases the cost of the valve and requires additional installation space, which is particularly disadvantageous for some applications. Furthermore, the actuator must not only be designed to move the valve spool against normal friction, but also overcome the spring force of the return spring. This requires a correspondingly powerful motor, which can lead to corresponding energy losses during operation. Fundamentally, the entire drive of the valve spool, including any gears, must also be designed so that the return spring can move the motor.

[0021] The pilot control device has the control and the electrical energy storage device, wherein the control and the electrical energy storage device are configured to move the valve spool from any possible valve spool position into a shut-off position by means of the valve drive and energy stored in the electrical energy storage device.

[0022] A hydraulic valve module with the described pilot control device comprises at least one and optionally several hydraulic valves, which may be arranged in a row one behind the other in a valve block. The hydraulic valve module preferably further comprises, for each hydraulic valve, a valve drive with a separately controllable electric actuator, with which the respective hydraulic valve or the hydraulic lines of the respective hydraulic valve can be supplied with hydraulic fluid in a targeted manner (according to the requirements of a higher-level operating control system) (i.e., can be selectively opened, closed, or partially opened and / or closed).

[0023] The electric actuator of a hydraulic valve comprises in particular a stepper motor with which the position of the valve spool can be adjusted in order to supply hydraulic lines with hydraulic fluid through the hydraulic valve.

[0024] The electric actuator can also include other types of electric drive motors. In principle, brushless motors (BLC motors, BLC = brushless contact), which also includes stepper motors, are particularly suitable for the electric actuator. However, other types of electric drive motors can also be used in the electric actuator. In principle, however, it is also advantageous if an electric drive motor is used in the electric actuator with which certain positions of a moving element of the motor can be adjusted by supplying current to the motor. Particular preference is given to using motors with which this position adjustability is possible even without additional position sensors and position control. This applies in particular to the stepper motors mentioned. Actual values ​​or measured values ​​can then, if necessary, be determined via the currents or voltages occurring in the motor / actuator.

[0025] Preferably, the electric drive motor of the actuator is a rotary motor with a stator and a rotor, wherein the rotor actuates the valve slide via a gear. In preferred embodiments, the gear comprises a rack for converting a rotation of the drive motor into a linear movement of the valve slide.

[0026] In other embodiments, the electric drive motor can also be a linear motor that directly generates a linear movement, which is particularly preferably transmitted to the valve spool via a rigid connection.

[0027] The control is designed as an emergency control and the electrical energy storage device as an emergency power supply and is configured to provide electrical energy for at least one emergency shutdown if a fault is detected in an external power supply of the hydraulic valve module, wherein the emergency shutdown is configured to move the valve spool from any possible valve spool position into the shutdown position.

[0028] The electrical energy storage device has at least one electrical energy storage cell in which the actual storage of the electrical energy takes place. Additionally, the electrical energy storage device can comprise further components. These are preferably components that control the feed of electrical energy into the energy storage device and / or the release of electrical energy from the energy storage device. For example, a charging control unit for controlling the charging and discharging of the electrical energy storage cell can be a further component of the electrical energy storage device.

[0029] The switch-off position of the valve spool is, in particular, a position in which all hydraulic lines are closed by the hydraulic valve. An emergency switch-off occurs, in particular, if a fault is detected in an external power supply of the hydraulic valve module. An external power supply here refers to all components, including electrical lines, for supplying the hydraulic valve with electrical energy that are located outside the hydraulic valve module. A failure can therefore occur due to defective components or lines. Lines and their connections outside the hydraulic valve module are particularly at risk in everyday operation. While the prior art required at least one return spring to ensure that the valve was moved to a safe switch-off position in the event of a power failure, the invention uses the actuator orThe motor is used, which, however, requires a certain minimum amount of energy, which is now constantly provided by the electrical energy storage device. The control system uses this energy to carry out the desired shutdown process via the actuator. Due to the constant friction, which can also be increased using suitable damping devices if necessary, the valve then remains in this safe state, even during normal operational vibrations. To minimize interference between the electrical energy storage device, the control system, and the actuator, these components are arranged very close to one another. This is also expressed by the term "hydraulic valve module," which describes a compact, integrated design of a group of hydraulic valves, associated actuators, and the other intended components (control system, electrical energy storage device, etc.). This design is also referred to here as a modular design.The module is preferably integrated in a larger machine (tractor, excavator, etc.) in a replaceable piece and, if possible, housed in a common protective housing, as explained above.

[0030] In a preferred embodiment, a plurality of hydraulic valves can be connected to the pilot control unit and supplied with data by it.

[0031] Preferably, the electrical energy storage device is also designed such that the valve spools of each hydraulic valve in the hydraulic valve module can be moved from any position to the (respectively provided) shut-off position. This means that even if all valve spools are in a position from which the energy required to return the valve spools to the shut-off position is maximum, the energy available in the electrical energy storage device is still sufficient to return all valve spools of the hydraulic valve module to the shut-off position.

[0032] It is also particularly preferred if the parameterization module, the control loop, and the bidirectional data acquisition are each configured such that they can be used for multiple hydraulic valves. Or, a controller configured on a microprocessor with a data memory is configured such that it can generate operating commands for a plurality of hydraulic valves, even under operating conditions. For example, the pilot control unit or the controller arranged therein can be configured such that five, ten, or possibly even 20 hydraulic valves can be supplied with operating commands.

[0033] In particular, the pilot control unit can have a protective circuit and / or other (other) common components for multiple hydraulic valves, so that these do not have to be present individually for each actuator. Thus, a controller in the pilot control unit can perform functions for multiple valves, for example, checking the integrity of the respective signal transmission, limiting the inrush current, detecting the failure of the external power supply, and initiating emergency shutdowns.

[0034] By using a pilot control unit for multiple hydraulic valves in a hydraulic valve module, it is also possible to loop signal and current-carrying lines. Particular preference is given to individual hydraulic valves in which the hydraulic valves are connected to one another in series, with each hydraulic valve or actuator of a hydraulic valve being connected to the adjacent hydraulic valves or their actuators. Hydraulic valves at the beginning or end of a series circuit typically have one adjacent hydraulic valve, and hydraulic valves within the series circuit typically have two adjacent hydraulic valves. The pilot control unit is then preferably connected only to a first hydraulic valve and / or to a last hydraulic valve in the series circuit.The signals and the current for further hydraulic valves in the series circuit are passed or looped through the connections between the hydraulic valves / actuators to the respective hydraulic valve / actuator.

[0035] As described above, it is advantageous if the pilot control unit has an interface for data exchange and / or reprogramming. The controller preferably contains the calibration data, parameters, and control loops required for at least one valve actuator, and is configured to operate the valve actuator as an actuator of the control loops and to process actual values ​​from the valve actuator.

[0036] Such actual values ​​can, for example, be measured values ​​determined by electronics in the valve actuator. The electronics in the valve actuator preferably have a memory in which such actual values ​​are stored for at least a certain period of time and which can be accessed subsequently if necessary to determine the actual values ​​from this memory. This can be very helpful, for example, for error diagnosis.

[0037] Particularly preferably, two or more of the functions of the parameterization module, control, control loops, and / or bidirectional data transmission are integrated into a microprocessor with data memory. Preferably, there is exactly one microprocessor in the pilot control unit, in which all essential functions take place. The microprocessor is preferably designed so that no overload occurs even during maximum data throughput events (e.g., when all connected hydraulic valves must receive new operating commands simultaneously).

[0038] A novel method for operating a valve drive for a hydraulic valve is also to be described here, wherein the valve drive receives operating commands from a separate described pilot control unit via a bidirectional data transmission and sends actual values ​​of the hydraulic valve back to the pilot control unit via the bidirectional data transmission and wherein the pilot control unit contains operating parameters for the valve drive and hydraulic valve stored in the parameterization module, which together with the actual values ​​and external specifications are used to generate the operating commands.

[0039] The advantages and design features described for the pilot control unit are applicable and transferable to the described method.

[0040] It is particularly advantageous if the pilot control unit takes over the control of the valve drive by means of control loops implemented in the control system and the stored operating parameters, and no control loops are implemented and no operating parameters are stored in the valve drive itself.

[0041] It is also advantageous if the pilot control unit supplies a plurality of valve actuators with operating commands in parallel or serially and stores operating parameters for all of these valve actuators.

[0042] Furthermore, a computer program product is to be described here which has instructions which cause a described pilot control device to operate according to the described method.

[0043] The computer program product can, for example, be implemented on a microprocessor with data memory in the control of the pilot control device.

[0044] The described pilot control device is explained in more detail below with reference to the figures. It should be noted that the figures are only schematic and are intended to illustrate the principles of the invention discussed here. Individual features or functions described in the exemplary embodiment can also be meaningfully combined within the scope of the invention in ways other than those shown. They show: Fig. 1a shows a schematic cross section through an individual hydraulic valve of a hydraulic valve module with a deflected position of the valve spool, Fig. 1b shows a schematic cross section through an individual hydraulic valve of a hydraulic valve module with a position of the valve spool in the switch-off position, Fig. 2 shows a schematic view of an inventive hydraulic valve module with its connections, and Fig. 3 shows a schematic view of an inventive pilot control device with its components and connections.

[0045] Fig. 1a and Fig. 1b show schematically the cross section through a hydraulic valve 1 with a valve drive 2 and an actuator 3, wherein this hydraulic valve 1 is a component of a hydraulic valve module 41 described here. Fig. 1a and 1bshow a section through such a hydraulic valve module 41, which runs through one of the hydraulic valves 1. The hydraulic valve 1 has a hydraulic valve block 4. This hydraulic valve block 4 can also be a common block in which several hydraulic valves 1 are arranged (one behind the other). The hydraulic valve 1 each comprises hydraulic lines 22, which can be designed, for example, as bores in the hydraulic valve block 4. A control bore 29 is also provided in the hydraulic valve block 4, in which a valve spool 5 is arranged. Control structures 30 exist on the valve spool 5, which interact differently with the hydraulic lines 22 depending on the position of the valve spool 5 and can supply them with hydraulic fluid in a targeted manner or can optionally open, close and / or partially open and / or partially close them. To illustrate the functioning of the hydraulic valve 1, the Fig. 1a and1b different positions of the valve slide 5 are shown. The position of the valve slide 5 can be adjusted with the motor / actuator 3. The motor / actuator 3 is designed in conventional variants with an electric motor 32 and a gear 33, via which the electric motor 32 drives a gear 35, which acts on a rack 34 connected to the valve slide 5. In the sectional view according to the Fig. 1a and 1b The gear 35 is arranged behind the rack 34 and is concealed by the rack 34. The current position of the valve spool 5 can then be adjusted via the rack 34 using the motor / actuator 3. Fig. 1a shows, by way of example, a position of the valve spool 5, in which one of the hydraulic lines 22 in the hydraulic valve block 4 is connected to a supply channel 37 for providing hydraulic oil in order to supply this hydraulic line 22 with hydraulic oil. Preferably, the valve spool 5 has a designated shut-off position. Schematically shown in the Fig. 1a and 1b also a pilot control unit 20 for controlling the valve drive 2. The valve drive 2 has an electronics unit 26 and a power output stage 27, which serve to supply the actuator 3 in the valve drive 2. The electronics unit 26 is configured to control the power output stage 27 to supply power to the actuator 3 in order to supply the actuator 3 with electrical energy as required according to the operating commands received by the electronics unit 26. The electronics unit 26 can also record and transmit measured variables in the valve drive 2.

[0046] The valve actuators 2 are connected to the pilot control unit 20 via an actuator current line 31. The actuator current line 31 also serves as a bidirectional data line 17. Control data from the pilot control unit 20 is transmitted to the electronics 26 via a bus system via the actuator current line 31, which operates as a bidirectional data line 17. Actual values ​​or measured variables from the valve actuator 2 are transmitted back to the pilot control unit 20 in the same way.

[0047] The pilot control unit 20 contains an electrical energy storage device 10 and a controller 19. The controller 19 performs the control tasks described above and supplies the electronics 26 of the valve actuator 2 with control commands. The electrical energy storage device 10 can, if necessary, ensure a power supply to the valve actuator 2. Electrical energy is stored in the electrical energy storage device 10, which is sufficient to move the valve spool 5 from any possible valve spool position to the shut-off position. The implementation of such a shut-off (possibly also an emergency shut-off) is also controlled by the controller 19.

[0048] To carry out the control of the valve drives 2, the control 19 has in the

[0049] Pilot control unit 20 has a parameterization module 28 in which operating parameters for the respective hydraulic valve 1 are stored. Furthermore, the controller 19 is configured to receive measured values ​​from the valve drive 2 (from the electronics 26) and to enable controlled operation of the hydraulic valve based on control data transmitted from a higher-level controller 19. A control circuit 38 is preferably also provided for this purpose. A bus system for communication between the controller 19 or the pilot control unit 20 and the electronics 26 or the valve drive 2 can be implemented with the bidirectional data transmission 39 shown schematically here.

[0050] All these functions can be implemented on a microprocessor with data memory 36.

[0051] The pilot control unit 20 is preferably connected to an external power supply 21 for powering the pilot control unit 20 and the hydraulic valves 1. Furthermore, the pilot control unit 20 is connected to a higher-level control system via a data supply line 16, for example, to an excavator control unit if the hydraulic valve 1 is used in an excavator.

[0052] Fig. 2 shows a described hydraulic valve module 41 with, in this example, four hydraulic valves 1, which are shown schematically here. Shown in each case is the hydraulic valve 1 with the hydraulic valve block 4 and the valve drive 2 comprising the actuator 3 as well as the power output stage 27 and the electronics 26. The actuator 3 is each configured to move the valve spool (not shown here) of the respective hydraulic valve 1. The actuators 3 are connected via the actuator power line 31, which also functions as a bidirectional data line 17 via a bus system, to a pilot control unit 20, which supplies them with power and control signals. The pilot control unit 20 is supplied with power via an external power supply 21 and receives operating commands for controlling the hydraulic valves 1 via a data feed line 16. The controller 19 and the electrical energy storage unit 10 are arranged here in the pilot control unit 20. For orientation, Fig. 2 the section direction AA is shown. The representation of the Fig. 1a and 1b show such a section through the hydraulic valve 1.

[0053] Fig. 3 shows schematically and with further details a possible structure of a described pilot control device 20 (as it is in Fig. 2 already shown) with its various components. The pilot control unit 20 is connected on the input side to an external power supply 21 and data lines 16 for supplying and controlling actuators 3. On the output side, an actuator current line 31 and a bidirectional data line 17 lead from the pilot control unit 20. Schematically indicated here is that the actuator current line 31 and the bidirectional data line 17 are designed with a (common) physical combined data and power line. During normal operation of the pilot control unit 20, current is simply passed through. However, a sensor 14 monitors the integrity of the external power supply 21 and transmits its measurement signals via a sensor line 15 to the controller 19. During normal operation, the electrical energy storage unit 10 is also charged via a charging circuit 9, so that the energy storage unit 10 is always fully charged shortly after each start of operation, but is not overcharged.The electrical energy storage device 10 can contain at least one accumulator 24 and / or at least one capacitor 23 as an electrical energy storage cell. Alternatively, however, as shown in FIG. Fig. 3 As indicated, a non-rechargeable battery 25 can also be used as an energy storage cell with a battery management system 13, in which case the charging circuit 9 is omitted. A voltage converter 12 serves to maintain a constant voltage at different voltage or charge states of the electrical energy storage device 10. This can be supported by an inrush current limiter 8 so that excessive inrush currents do not occur. The controller 19 is connected to all components via signal lines 18 so that it can preferentially control all processes that occur in the pilot control unit 20.

[0054] If the sensor 14 of the controller 19 reports a fault in the external power supply 21, the controller 19 switches from the external power supply 21 to a power supply via the electrical energy storage device 10 using a changeover switch 7. All actuators 3 are now supplied with power from the electrical energy storage device 10. At the same time, the controller 19 interrupts the data supply line 16 and sends signals to move the valve spools 5 to the shut-off position or for an emergency shutdown via the bidirectional data line 17. An optional protective circuit 6 prevents interference with this process by the external power supply 21. An emergency shutdown can also be triggered, for example, if there are interruptions in the data supply line 16 or elsewhere in data communication. In this case, however, the electrical energy storage device or the emergency power supply is not required.

[0055] Upon restarting after an emergency shutdown, the electrical energy storage device 10 (if discharged) is quickly recharged, enabling safe operation again. The pilot control unit 20 can also perform additional functions, such as regularly checking all data and signal lines and the energy storage device 10. Exemplary calculations for typical state-of-the-art hydraulic valves and actuators show that the energy storage device 10 should store at least approximately 4 Ws [watts per second] for each valve and each emergency shutdown. The capacity of the electrical energy storage device 10 can therefore be calculated based on the number of connected valves and the number of desired emergency shutdowns that can be performed, and can of course be increased for safety and to account for the aging of the energy storage device 10.A voltage drop that occurs when the energy storage device 10 is connected can be compensated by the voltage converter 12. As a result, an emergency power supply according to the invention should have an energy storage device 10 of at least 12 Ws, which can be achieved for the desired operating voltage, in particular 12 V [volts], by interconnecting so-called supercapacitors and / or accumulator cells (e.g., lithium-ion batteries). The costs and other technical properties of these components determine the best method for energy storage for each application.

[0056] The controller 19 is (as already explained above) preferably implemented on a microprocessor. The controller 19 processes control commands for the hydraulic valves 1 received from the pilot control unit 20 via the data supply line 16 during regular operation in order to generate suitable control signals for the actuators of the hydraulic valves or their power output stages. For this purpose, the controller 19 has a bidirectional data transmission 39 that manages a bus system for communication between the pilot control unit 20 and the electronics of the individual valve drives. With the bidirectional data transmission 39, the actuator current line 31 is operated as a bidirectional data line 17, with which control data can be transmitted to the hydraulic valve modules 41 or measurement data can be received from the hydraulic valve modules 41.The controller 19 further comprises a parameterization module 28 in which operating parameters for each individual hydraulic valve 1 connected to the pilot control unit 20 can be stored. The parameterization module 28 can be parameterized via an interface 40 on the pilot control unit 20. This means that operating parameters, characteristic maps, etc. can be processed or stored in the parameterization module 28 via this interface 40. The controller 19 further comprises a control loop 38. The control loop 38 is characterized in that it generates suitable operating commands for the actuator 3 of the hydraulic valve or its power output stage, taking into account the operating commands received via the data supply line 16, the parameters stored in the parameterization module 28, and the measurement or sensor data received via the bidirectional data line 17 from the valve drive 2 or its electronics 26.Control circuits 38 are no longer required in the individual hydraulic valve 1. The control circuits 38 required for controlled operation are completely implemented in the pilot control unit 20 or are closed by the pilot control unit 20.

[0057] The present invention allows the particularly efficient parameterization of hydraulic valves, whereby such valves can be applied more cost-effectively than with conventional pilot control devices. List of reference symbols

[0058] 1 Hydraulic valve 2 Valve drive 3 Actuator 4 Hydraulic valve block 5 Valve spool 6 Protective circuit 7 Changeover switch 8 Inrush current limiter 9 Charging circuit 10 Power storage, energy storage 11 Status line 12 Voltage converter 13 Battery management 14 Sensor 15 Sensor line 16 Data feed line 17 Bidirectional data line 18 Signal lines 19 Controller 20 Pilot control unit 21 External power supply 22 Hydraulic lines 23 Capacitor 24 Accumulator 25 Battery 26 Electronics 27 Power output stage 28 Parameterization module 29 Control bore 30 Control structures 31 Actuator power line 32 Electric motor 33 Gearbox 34 Rack 35 Gear 36 Microprocessor with data memory 37 Supply channel 38 Control loop 39 Bidirectional data transmission 40 Interface 41Hydraulic valve module

Claims

1. Pilot control unit (20) for at least one valve drive (2) of a hydraulic valve (1) with a valve slide (5), wherein the valve slide (5) can be adjusted by the valve drive (2), in order to supply hydraulic lines (22) with hydraulic fluid through the hydraulic valve (1), wherein the pilot control unit (20) is set up to supply electronics (26) and a power end stage (27) for actuating an electrical actuator (3) of the valve drive (2) with electrical energy and operating commands, wherein for the supply of the electronics (26) with operating commands the pilot control unit (20) comprises a control (19), in which for this purpose a parametrization module (28) is present, in which operating parameters for the operation of the at least one hydraulic valve (1) by the valve drive (2) thereof are stored, characterized in that the pilot control unit (20) has an electrical energy store (10), wherein the electrical energy store (10) is set up so that the valve slide (5) is moved by the valve drive (2) and energy stored in the electrical energy store (10) from any possible valve slide position into a cutout position, wherein the respective setup of the electrical energy store (10) is realized by the control (19) set up for this purpose in the pilot control unit, wherein the control (19) is configured as an emergency control and the electrical energy store (10) as an emergency power supply and they are set up to supply electrical energy for at least one emergency cutout, when a fault is detected in an external power supply (21) of the hydraulic valve (1), wherein the emergency cutout is set up to move the valve slide (5) from each possible valve slide position into the cutout position.

2. Pilot control unit (20) according to Claim 1, wherein there is at least one control loop (38) for controlling the valve drive (2) and a bidirectional data transmission (39) to the valve drive (2) in the control (19).

3. Pilot control unit (20) according to one of the preceding claims, wherein a plurality of hydraulic valves (4) is connectable to the pilot control unit and can be supplied with data by said pilot control unit.

4. Pilot control unit (20) according to Claim 3, wherein the pilot control unit (20) has a protective circuit (6) and / or further joint components for multiple hydraulic valves (1).

5. Pilot control unit (20) according to one of the preceding claims, wherein the pilot control unit (20) has an interface (40) for data exchange and / or reprogramming.

6. Pilot control unit (20) according to one of the preceding claims, wherein the control (19) contains the calibration data, parameters and control loops (38) needed for at least one valve drive (2), and it is set up to operate the valve drive (2) as an actuating element of the control loops (38) and to process actual valves of the valve drive (2).

7. Pilot control unit (20) according to one of the preceding claims, wherein two or more of the functions of the parametrization module (28), control (29), control loops (38) and / or bidirectional data transmission (39) are integrated in a microprocessor (36) with a data store.

8. Method for operating a valve drive (2) for a hydraulic valve (1), wherein the valve drive (2) receives operating commands from a separate pilot control unit (20) according to one of the preceding claims via a bidirectional data transmission (39) and sends actual values of the hydraulic valve (1) back to the pilot control unit (20) via the bidirectional data transmission (39), and wherein the pilot control unit (20) contains operating parameters stored in the parametrization module (28) for the valve drive (2) and hydraulic valve (1), which are used along with the actual values and external inputs to generate the operating commands.

9. Method according to Claim 8, wherein the pilot control unit (20) takes over control of the valve drive (2) by means of control loops (38) realized in the control (19) and the stored operating parameters and no control loops (38) are realized in the valve drive (2) itself and no operating parameters are stored.

10. Method according to Claim 8 or 9, wherein the pilot control unit (20) supplies a plurality of valve drives (2) with operating commands in parallel or in series and stores operating parameters for all these valve drives (2).

11. Computer program product having commands which cause a pilot control unit (20) according to one of Claims 1 to 7 to carry out the method according to one of Claims 8 to 10.