EP4118343A1 - Hydraulic valve module for safe deactivation in the case of failure of an external current supply, and method for operating a hydraulic valve - Google Patents

Abstract

The present invention relates to a hydraulic valve module (1) having at least one hydraulic valve (4) with a valve slide (5) which can be adjusted by way of an electric actuator (3) in order to supply hydraulic lines (22) with hydraulic liquid by way of the hydraulic valve (4), wherein the hydraulic valve module (1) has a controller (14, 15, 19) and an electric energy store (8, 10, 12), wherein the controller (14, 15, 19) and the electric energy store (8, 10, 12) are set up to move the valve slide (5) out of every possible valve slide position into a deactivation position (36) by way of the electric actuator (3) and energy which is stored in the electric energy store (8, 10, 12). This allows the safe operation of hydraulic valves without a restoring spring, wherein valves of this type and the actuators thereof can be of smaller and less expensive construction than in the case of conventional valves with a restoring spring.

Description

Hydraulic valve module for safe shutdown in the event of an external power supply failure and method for operating a hydraulic valve

The present invention relates to 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. In such applications in particular, it is important that the hydraulic valves are very robust against external influences, in particular also vibrations, and that the desired valve positions can be set reliably in all operating situations.

Typical hydraulic valves for the above applications have a valve slide that is moved by a motor, also called an actuator. The valve slide can be brought into different positions, which means that hydraulic lines can be (partially) opened or closed as required. Such actuators and hydraulic valves are described, for example, in EP 3 121 485 A1 or US 2008/0121830 A1. According to the prior art, it is customary for the valve slide to be brought into or held in a rest position by means of at least one return spring when the drive is not active. This is e.g. B. described in EP 3 483 454 A1. This ensures safe shutdown of such a hydraulic valve, especially in the event of a power supply failure. With a suitable integration of the hydraulic valve in the control of a controlled movement element (excavator shovel, fork of a tractor, etc.), safe operation of the controlled movement element can also be guaranteed by safely switching off the hydraulic valve.

However, the return spring described 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 unfavorable for some applications. In addition, the actuator must not only be designed to move the valve rod against normal friction, but also overcome the spring force of the return spring. the. This requires a correspondingly powerful motor, which can lead to overall corresponding energy losses during operation. In principle, the entire drive of the valve rod, including any gears, must be designed so that the return spring can move the motor.

Proceeding from this, the present invention is intended to create a hydraulic valve module and a method for the safe operation of a hydraulic valve which manage without a return spring and thereby avoid some of the disadvantages described without compromising safety.

A hydraulic valve module according to independent claim 1 and the method described serve to achieve these objects. Advantageous refinements and / or developments, to which the invention is not limited, are specified in the respective dependent claims. The invention also comprises a computer program product, comprising instructions which cause the hydraulic valve module described to carry out the methods described.

A hydraulic valve module according to the invention has at least one hydraulic valve with a valve slide, the valve slide being adjustable with an electrical actuator in order to supply hydraulic lines through the hydraulic valve for hydraulic fluid, the hydraulic valve module having a controller and one with an electrical energy store, the controller and the electrical energy store are set up to bring the valve slide with the electrical actuator and energy stored in the electrical energy store from every possible valve slide position into a switch-off position.

A hydraulic valve module comprises at least one and possibly several hydraulic valves, which are optionally arranged in a row one behind the other in a valve block. The hydraulic valve module preferably further comprises a separately controllable electrical actuator for each hydraulic valve with which the respective hydraulic valve or the hydraulic lines of the respective hydraulic valve are selectively (according to the requirements of a higher-level controller) with hy- hydraulic fluid can be supplied (that is, specifically opened, closed or partially opened and / or closed).

The hydraulic valve module also has, in particular, the control of the electrical actuator and the electrical energy store, which are described in detail below. The electrical energy store and the controller form parts of the hydraulic valve module and as such are preferably arranged directly on the other components of the hydraulic valve module (on the at least one hydraulic valve, on the electrical actuator, etc.) and preferably also connected to these additional components. The controller and the electrical energy store can be arranged, for example, with the electrical actuator and / or the hydraulic valve in a common housing and / or in a housing which is attached (for example screwed) to the electrical actuator and / or the hydraulic valve.

In particular, oils are used as the hydraulic fluid in such hydraulic valves.

Hydraulic lines are usually designed as channels within a valve block of the hydraulic valve. The valve slide is arranged within a channel in the valve block and the valve slide preferably has fluid control structures which interact with hydraulic lines in such a way that, depending on the position of the valve slide, the hydraulic lines are specifically supplied with hydraulic fluid. This means that hydraulic lines are either opened or closed (if necessary also partially opened or closed).

The valve slide is usually a slide that can be moved along an axis and a valve slide position and the switch-off position mean positions of the valve slide along the axis, the term "valve slide position" here meaning any position, while the term "switch-off position" here means a very specific one describes a (fixed) defined position. "Any valve spool position" is any position that the valve Slide can take in a range of motion between the maximum deflected positions of the valve slide. The switch-off position is preferably located in the middle within the range of motion or at a distance from the maximum deflected positions of the valve slide, so that the valve slide can be moved in both directions starting from the switch-off position in order to be able to quickly put the hydraulic valve back into operation after a switch-off.

The electric actuator includes, in particular, a stepper motor with which the position of the valve slide can be adjusted in order to supply hydraulic lines with hydraulic fluid through the hydraulic valve.

The electric actuator can, however, also comprise other types of electric drive motors. Basically, brushless motors (BLC motors, BLC = brushless contact) are particularly suitable for the electrical actuator, which also includes stepper motors. 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 movable element of the Mo sector can be set by energizing the motor. It is particularly preferred to use motors in which this adjustability of the position is also possible without additional position sensors and position control. This applies in particular to the stepper motors mentioned.

The electric drive motor of the actuator is preferably a rotary motor with a stator and a rotor, the rotor actuating the valve slide via a gear. In preferred embodiments, the transmission comprises a toothed rack for converting a rotation of the drive motor into a linear movement of the valve slide.

In other design variants, the electric drive motor can also be a linear motor, which directly generates a linear movement that is particularly preferably transmitted to the valve slide by a rigid connection. The control is, in particular, a control device in which a program is stored, according to which the movement of the valve slide can be carried out from any possible valve slide position into the switch-off position. This program is preferably permanently stored in a data memory of the controller.

It is particularly preferred if the control is designed as an emergency control and the electrical energy storage is designed as an emergency power supply and is set up to provide electrical energy for at least one emergency shutdown when a fault is detected in an external power supply of the hydraulic valve module, the emergency shutdown being set up for this purpose To bring the valve slide from every possible valve slide position into the switch-off position.

The electrical energy store has at least one electrical energy store cell in which the actual storage of the electrical energy takes place. In addition, the electrical energy store can comprise further components. These are preferably components that control the feeding of electrical energy into the energy store and / or the delivery of electrical energy from the energy store. For example, a charging control device for controlling the charging and discharging of the electrical energy storage cell can be a further component of the electrical energy storage.

It is particularly advantageous if no mechanical return spring is arranged in the at least one hydraulic valve module, with which the valve slide can be passively brought into a switch-off position.

It is particularly preferred that there is no spring-driven movement of the valve slide in the event that a power supply for the hydraulic valve module fails.

This can mean in particular that the actuator is designed to be smaller or weaker than in similar valves with a return spring (which means that it is also less Energy consumed for the same switching processes). This can also mean that self-locking gear such. B. worm gears can be used in the actuators / motors of the hydraulic valves.

The control or the emergency control and the energy store or the emergency power supply are set up in particular to perform an emergency shutdown without the support of a return spring.

The shut-off position of the valve slide is in particular a position in which all hydraulic lines are closed by the hydraulic valve. An emergency shutdown occurs in particular if an error is detected in an external power supply of the hydraulic valve module. An external power supply is understood here to mean all components, including electrical lines for supplying the hydraulic valve with electrical energy, which 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 at risk in everyday operation. While according to the prior art at least one return spring ensured that the valve was brought into a safe switch-off position in the event of a power failure, according to the invention the actuator or motor is used for this, which, however, requires a certain minimum energy, which is now constantly from the electrical energy store is kept ready. The control uses this energy to carry out the desired shutdown process by means of the actuator. Due to the always existing friction, which can also be increased by suitable damping means if necessary, the valve then remains in this safe state, even with normal operational vibrations. In order to rule out interference between the electrical energy storage system, the controller and the actuator as far as possible, 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, electrical energy storage, etc.). Such a construction is also referred to here as a modular construction. net. The module is preferably integrated in one piece, replaceable, in a larger machine (tractor, excavator, etc.) and, if possible, also housed in a common protective housing, as has already been explained above.

The switch-off position is also preferably at the same time a calibration position which is activated or can be controlled with the valve slide for calibration. When operating hydraulic valves of this type, the case may arise that a calibration is lost due to slippage in the actuator / motor and the current position of the valve slide is not exactly known in a controller. This applies in particular when a stepper motor is used in the actuator / motor, in which a step loss can also occur. In such a situation in which the calibration has been lost, the valve slide can then be brought into the calibration position in a targeted manner so that the position of the valve slide is then known again in the control.

According to the invention, the valve slide preferably has a position marking which enables the switch-off position to be found and / or the position of the valve slide to be calibrated. In the case of valve spools with a return spring, such a position marking is not available and is only advantageous to a limited extent because the return spring is used to bring the valve spool (passively) back into a switch-off position if the current position of the valve spool cannot be correctly identified. Without a return spring and such a procedure, it can be advantageous to use another method or other means in order to detect the switch-off position. It has been found that a position marking on the valve slide is very advantageous for this. The presence of the shut-off position of the valve slide can be recognized on the basis of the position marking. In preferred embodiment variants, the position marking can be recognized with the controller and the actuator on the basis of an anomaly in the path-force relationship or the force profile of the movement of the valve slide. Position markings are possible which are recognized or scanned with corresponding (additional) sensors and / or switches. Magnetic, capacitive or optical sensors can be used. It when a mechanical position marker, in particular special in the form of a groove (on the valve slide) is attached is particularly advantageous. By means of a snap-in spring that engages in the groove in the switch-off position, a mechanical resistance can then be created that can be determined on the actuator or by the controller, so that only the energy consumption or the electrical current required for movement is supplied to the actuator Determination of the shutdown position must be observed. If the switch-off position is also a calibration position, a very similar method can be used for calibration as was previously the case with a return spring on the valve slide. If the groove for the snap-in spring leaves a little play (and there may also be inclined flanks of the groove or snap-in spring), the center of the position marking can be determined by moving the valve slide back and forth up to a defined increase in force.

The position marker can also be used for a switch-on procedure for the hydraulic valve module. With each switch-on process, a position that is maximally deflected to the right (or away from the drive) and to the left (or towards the drive) is approached starting from the position marking or starting from the calibration position. A maximally deflected position can also be recognized on the basis of a characteristic property of the path-force relationship or the force profile of the movement of the valve slide, this recognition preferably also taking place with the actuator and the controller. An increase in the force or the current that is necessary to move the actuator usually increases outwards (right / left). The outer position can be defined by a threshold value for this force or this current. The switch-on procedure can be stored in the control. The control is preferably set up in such a way that proper functioning of the hydraulic valve module is reported when the switch-on procedure for all hydraulic valves of the hydraulic valve module has been carried out as expected.

In a preferred embodiment of the invention, a hydraulic valve module includes a plurality of hydraulic valves and a common electrical valve Energy storage device, the electrical energy storage device being designed to move a plurality of valve slides from every possible valve slide position into the switch-off position.

The electrical energy store is preferably designed in such a way that the valve slides of each hydraulic valve in the hydraulic valve module can be used from any position into the (respectively provided) switch-off position. This means that even in the event that all valve spools are in a position from which the energy expenditure to bring the valve spool back into the switch-off position is at a maximum, the energy available in the electrical energy storage device is still sufficient to power all valve spools Bring the hydraulic valve module back into the switch-off position.

It is particularly advantageous if the actuators of the various hydraulic valves and the electrical energy store are connected to the external power supply via an inrush current limiter so that they can be switched on one after the other.

In previously known valve blocks with several hydraulic valves and their actuators, very high currents are required when switching on, because all actuators are started up at the same time. Such currents do not occur later during operation. The inrush current limiter is preferably set up to modify control commands to the actuators of the hydraulic valves in such a way that they are offset from one another in such a way that the summed inrush currents of the actuators of the hydraulic valves of the hydraulic valve module are limited below a (predefined or predefinable) limit value. With an inrush current limiter for several actuators, the actuators can be switched on one after the other, which only insignificantly delays the entire switch-on process, but limits the current even when switched on to the inrush current of only one actuator plus the regular operating currents of the other actuators. The inrush current limiter described here can in particular also be referred to as a switch-on delay or switch-on delay. Due to the inrush current limiter, other electrical installations for supplying the hydraulic valve module with electrical power can be designed to be considerably smaller.

In an embodiment according to the invention, the electrical energy store comprises at least one electrical energy storage cell that can be charged by the external power supply.

This rechargeable electrical energy storage cell is charged immediately after operation of the hydraulic valve module with a functioning external power supply, so that it is practically always available during operation after a very short start-up phase in order to bring the valve slide into the intended switch-off position or the emergency shutdown perform. The chargeable electrical energy storage cell can also be designed to be large enough for a plurality of corresponding valve slide movements (emergency shutdowns) so that it is immediately available again after a plurality of corresponding valve slide movements (emergency shutdowns) when operation is resumed.

In principle, it depends on economic and technical considerations which type of electrical energy storage cell is used. The aim is, of course, not to lose the cost advantages achieved by eliminating a return spring through an expensive electrical energy storage cell. A preferred possibility is that the electrical energy storage cell comprises at least one capacitor and / or one accumulator.

However, a (non-rechargeable) battery can alternatively be used if cost / benefit considerations show that this is more favorable for an application. This will be the case in particular if corresponding valve slide movements / emergency shutdowns occur very rarely and changing the battery at certain time intervals (e.g. during maintenance work) is acceptable. In a particular embodiment of the invention, the control and the electrical energy storage device are arranged in a pilot control device in the hydraulic valve module and / or the control and the electrical energy storage device are part of the pilot control device. The pre-control device is in particular a pre-control device of the at least one electrical actuator. The external power supply of the hydraulic valve module is connected to the pilot control device or the actuators are connected to the external power supply of the hydraulic valve module via the pilot control device. This pilot control device, which can also contain other components, always supplies the actuator with the necessary energy and control commands. In undisturbed operation, the result is practically a passive device that passes current and control commands through, but in the event of disturbances in the external power supply, it becomes an active device and supplies energy and control commands for an emergency shutdown.

The inrush current limiter already described above is preferably also part of this pre-control device and this is thus also connected between the actuators and the external power supply.

The pilot control device described here is in particular a (common) pilot control device for all hydraulic valves in the hydraulic valve module. The described components (control, electrical energy storage etc.) are, as stated, preferably present in the hydraulic valve module centrally for several (preferably for all) hydraulic valves of the hydraulic valve module. However, design variants are also possible in which these components (possibly also in the form of a pilot control device) are available individually for each hydraulic valve. If necessary, these components can each also be arranged within the actuator of the respective hydraulic valve.

The upstream control device can in particular have a protective circuit and / or further (other) common components for several hydraulic valves, so that these do not have to be available individually for each actuator. A controller in the pilot control device can take over functions for several valves, for example wisely check the integrity of the respective signal transmission, limit the inrush current, determine the failure of the external power supply and initiate emergency shutdowns.

The pilot control device preferably has at least one sensor with which the external power supply can be monitored, the controller in the pilot control device being set up to perform an emergency shutdown if the sensor detects a fault in the external power supply. An error can e.g. B. the failure, an excessive fluctuation or an overvoltage of the external power supply. The type of external power supply can be selected and configured independently of the invention.

It may be desirable to only have to perform an emergency shutdown in rare cases. An emergency shutdown should only be carried out in rare cases, especially when the emergency power supply or the energy storage device is under load. Therefore, all options for ensuring an external power supply when operating in a vehicle can and should also be exploited, which can also mean that the pilot control device can be connected to both the ignition plus and the permanent plus (connection to the battery) of the vehicle an emergency shutdown can be carried out with the aid of the vehicle battery if the sensor detects an unexpected shutdown of the vehicle while actuators are still in the working position. In this case, the pilot control unit continues to connect the external power supply from the vehicle battery, but sends signals for an emergency shutdown to each actuator.

By using a pilot control device for several hydraulic valves in one hydraulic valve module, it is also possible to loop lines carrying signals and current. Particularly preferably, individual hydraulic valves in the hydraulic valve are connected to one another by a series connection, each hydraulic valve or each actuator of a hydraulic valve being connected to the adjacent hydraulic valves or its actuator. In this case, hydraulic valves at the beginning of a series connection or at the end of a series connection usually have an adjacent hydraulic valve and hydraulic valves within the series Series connection of two adjacent hydraulic valves. The upstream control device is then preferably only connected to a first hydraulic valve and / or to a last hydraulic valve of the series circuit. The signals and the current for further hydraulic valves of the series connection are passed through or looped through the connections of the hydraulic valves / actuators to the respective hydraulic valve / actuator concerned.

Another advantage of the pilot control device is that an electrical safety circuit, current limitation (inrush limiter), reverse polarity protection, voltage conditioning (step-up converter) only need to be provided in the pilot control device and the individual actuators can have much less extensive control electronics . If necessary, the use of such a pilot control device even completely eliminates the need for control electronics for the individual actuators and the electric drive motors arranged therein.

The invention also relates to a method for the safe operation of a hydraulic valve without a mechanical return spring, a valve slide in the hydraulic likventil (preferably exclusively) being moved by an electric valve drive and held in predeterminable positions, with further automatic on detection of a fault in an external power supply an electrical energy storage device is switched over and the valve slide is moved into a safe, predeterminable switch-off position.

The method described is preferably carried out with a hydraulic valve module described above, the essential method steps (detection of the error and automatic switching from the external power supply to the electrical energy store) being carried out in the control of the hydraulic valve module.

With the method described, inherent safety can be ensured even without a return spring. It is even possible, depending on the condition of the valve If a malfunction occurs, different positions must be specified as the switch-off position or another process must be completed.

The electrical energy store is preferably charged by the external power supply in buffer mode and held ready for an emergency shutdown during normal operation of the hydraulic valve.

In a preferred embodiment of the method, the shutdown position is determined or the position of the valve slide is calibrated by means of a position marking on the valve slide, in particular by means of a groove into which a spring engages, so that the resulting force profile can be measured by the actuator. The spring is preferably arranged in a stationary manner on the actuator or on a housing of the actuator. When the valve slide is moved, an interaction occurs between the position marking and the spring, which causes the force profile described. The actuator preferably recognizes the position marking on the basis of an anomaly in the force profile.

The position marking is also particularly helpful for calibration if the actuator detects a so-called loss of step during a movement. This process is described, for example, in EP 3 142 244 A1. If a return spring is present, the switch-off position can easily be reached in the event of a loss of step by deactivating the actuator and the switch-off position setting itself by the acting spring force. In the embodiment variant described here, the position marking and calibration is possible. If a step loss has been determined, the switch-off position for calibration can be approached in a targeted manner and recognized on the basis of the position marking.

As will be explained in more detail with reference to the drawing, the hydraulic valve module generally contains a microprocessor that evaluates the signals from the sensor, regulates the buffer mode, forwards control signals or even generates it in the event of an emergency shutdown. The invention therefore also includes a computer program product which comprises commands which cause the hydraulic valve module described to carry out the methods described. An exemplary embodiment of the invention, to which it is not limited, is explained in more detail below with reference to the figures. It should be pointed out that the figures are only schematic and are intended to explain the principles of the invention dealt with here. Individual described features or functions of the exemplary embodiment can also be meaningfully combined with one another within the scope of the invention in a manner other than that shown. Show it

La is a schematic cross section through a single hydraulic valve of a hydraulic valve module with a deflected position of the valve slide,

1b shows a schematic cross section through an individual hydraulic valve of a hydraulic valve module when the valve slide is in the switch-off position,

2 schematically shows a hydraulic valve module according to the invention with its connections,

3 schematically a pilot control device according to the invention with its components and connections,

Fig. 4a schematically shows a first representation of a valve slide with Positionsmar marking and locking element,

4b schematically shows a second representation of a valve slide with position marking and latching element,

4c schematically shows a third representation of a valve slide with position marking and latching element,

5a schematically shows a first representation of a valve slide with a further type of position marking, Fig. 5b schematically shows a second representation of a valve slide with a wide Ren type of position marking

5c schematically shows a third illustration of a valve slide with a further type of position marking

Fig. La and Fig. Lb show schematically the cross section through a hydraulic valve

4 with the actuator 3, this hydraulic valve 4 being part of the hydraulic valve module 1 described here. FIGS. 1 a and 1 b show a section through such a hydraulic valve module 1, which runs through one of the hydraulic valves 4. The hydraulic valve 4 has a valve block 28. This valve block 28 can also be a common block in which several hydraulic valves 4 are arranged (one behind the other). The hydraulic valve 4 each includes hydraulic lines 22, which can be designed as bores in the valve block 28, for example. A control bore 29 is also provided in the valve block 28, in which a valve slide 5 is arranged. On the valve slide 5 there are control structures 30 which, depending on the position 31 of the valve slide, interact differently with the hydraulic lines 22 and supply them with hydraulic fluid in a targeted manner or, alternatively, can open, close and / or partially open and / or partially close. Position 31 of the valve slide

5 can be set with the motor / actuator 3. The motor / actuator 3 is designed in übli chen design 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 FIGS. La and lb, the gear 35 is arranged behind the rack 34 and covered by the rack 34. The current position 31 of the valve slide 5 can then be set with the motor / actuator 3 via the toothed rack 34. Fig. La shows an example of a position 31 of the valve slide in which one of the hydraulic lines 22 in the valve block 28 is connected to a supply line 37 to supply this hydraulic line 22 with hydraulic oil. The valve slide 5 preferably has an intended switch-off position 36, which is particularly preferably implemented by a position marking 26 on the valve slide 5. The position marking 26 is embodied in particular in such a way that it interacts with a spring 27 when the valve slide is in the shut-off position. This situation is shown in Fig. Lb. Such a position marking 26 is explained in more detail below with reference to FIGS. 4a to 4c and FIGS. 5a to 5c. The electrical energy store 10 and the controller 19 are also shown schematically in FIG The implementation of such a shutdown (possibly also an emergency shutdown) is controlled by the controller 19.

2 shows a hydraulic valve module 1 according to the invention with, in this example, four hydraulic valves 4, each of which is assigned an actuator 3, which is set up to move the valve slide, not shown here, of the respective hydraulic valve 4. The actuators 3 are connected via electrical lines 2 to a control unit 20, which supplies them with energy and control signals. The pilot control device 20 is supplied with power via an external power supply 21 in normal operation. The controller 19 and the electrical energy store 10 are arranged here in the front of the control unit 20. A data feed line 16 supplies signals for the control of the valves 4, which in turn supply hydraulic lines 22 with hydraulic fluid accordingly. For orientation purposes, the section direction A-A is shown in FIG. 2. The illustration in FIGS. 1 a and 1 b show such a section through the hydraulic valve module 1.

FIG. 3 shows schematically and with further details the structure of a described pilot control device 20 (as it is already shown in FIG. 2) with its different components. The input side of the pilot control device 20 is connected to an external power supply 21 and data lines 16 for supplying and controlling actuators 3. On the output side, an actuator power line 2 and a data line 17 go from the pilot control device 20. In passive operation of the pilot control device 20, current and signals are simply passed through. However, monitored a sensor 14 checks the integrity of the external power supply 21 and forwards its measurement signals to the controller 19 via a sensor line 15. During normal operation, the electrical energy store 10 is also charged via a charging circuit 9, so that the energy store 10 is always fully charged shortly after each start of operation, but is not overcharged. The electrical energy store can contain at least one accumulator 24 and / or at least one capacitor 23 as an electrical energy storage line. Alternatively, however, as indicated in FIG. 3, a non-rechargeable battery 25 can also be used as an energy storage cell with a battery management 13, the charging circuit 9 then being omitted. A voltage converter 12 is used to maintain a constant voltage with different voltage or charge states of the electrical energy store 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 preferably control all processes that occur in the pilot control device 20.

When the sensor 14 reports a fault in the external power supply 21 to the controller 19, the controller 19 uses a switch 7 to switch from the external power supply 21 to a power supply by means of the electrical energy store 10. All the actuators 3 are now supplied with power from the electrical energy store 10. At the same time, the controller 19 interrupts the data feed line 16 and sends signals to bring the valve slide into the switch-off position or for an emergency switch-off via the data transmission 17. An optional protective circuit 6 prevents disturbances of this process by the external power supply 21 be triggered when there are interruptions in the data line 16 or elsewhere in a data communication. Then, however, the electrical energy store or the emergency power supply is not required.

When restarting after an emergency shutdown, the electrical energy store 10 (if it is discharged) is quickly recharged so that safe operation is possible again. The front of control unit 20 can also have further radio take over tasks, for example the regular checking of all data and signal lines and the energy storage. Exemplary calculations for typical hydraulic valves and actuators according to the state of the art show that the energy storage device should have stored at least approx. 4 Ws [watts x second] for each valve and each emergency shutdown. The capacity of the electrical energy store 10 can therefore be calculated according to the number of valves connected and the number of ge desired feasible emergency shutdowns and of course provided with a surcharge for safety and to take into account aging of the energy store. A voltage drop that occurs when the energy store 10 is switched on can be compensated for by the voltage converter 12. As a result, an emergency power supply according to the invention should have an energy store 10 of at least 12 Ws, which for the desired operating voltage, in particular 12 V [volts], through the interconnection of so-called supercapacitors and / or accumulator cells (e.g. lithium-ion batteries) can be reached. The cost and other technical properties of these components determine the best way to store energy for each application.

4a to 4c show a valve slide 5 with a position marking 26 in the form of a groove 26 into which a latching element 27 can latch, the latching element 27 being designed here in the form of a spring clip. The latching element 27 and the groove 26 are shaped and arranged in such a way that the latching element 27 latches into the groove 26 precisely in the shut-off position, which can be at a different location for each valve type, which is noticeable in the actuator 3 because a resistance is overcome must be in order to push the latching element 27 out of the groove 26 again. This resistance and its location can be measured, in both directions, so that the exact position can be determined in this way. In Fig. 4a the situation is shown when the spring 27 engages in the position marking 26 designed in the form of a groove 26 when the valve slide 5 is in the shut-off position. Fig. 4b shows the case that the valve slide 5 is not in the switch-off position. Then the spring 27 is spread open. FIG. 4c shows the case from FIG. 4a (valve slide 5 in switch-off position) again in FIG another perspective to mark the interaction of the spring 27 and position or groove 26 to illustrate.

It should be pointed out that the type of position marking 26 shown here is, of course, only to be understood as an example. It is preferred that the position marking 26 for the actuator / motor 3 can be felt and can thus be recognized by the electronics or the control of the motor without further sensors being required for this. As a result, the actuator / motor 3 can always be used to move to the switch-off position for calibrating the hydraulic valve, which is preferably also a calibration position at the same time.

A further variant of the position marking is shown in FIGS. 5a to 5c. It can be seen here, in each case a valve slide 5 with a toothed rack 34 with which the valve slide 5 can be moved. Fig. 5a shows the valve slide 5 with the rack 34 in a view together with parts of the actuator and in particular with a gear 33 of the actuator. In FIGS. 5b and 5c, the valve slide 5 with the toothed rack 34 is shown in a side view (FIG. 5b) and in a top view (FIG. 5c). On the valve slide 5, a height profile 39 is provided on the side, on which a spring-loaded switch 38 rests. The switch 38 is pressed against the height profile 39 and based on the height profile, depending on the position of the valve slide 5, a certain position of the switch 38 results can be recognized on the basis of these rising flanks 40. Particularly preferably, a profile height 41 is different on both sides of the switch-off position 36, so that the position of the switch 38 can be used to identify in which direction the valve slide 5 is extended.

The switch 38 is preferably connected to the controller so that the information about the position of the valve slide 5 that can be obtained with the switch 38 can be taken into account. The present invention allows the safe operation of hydraulic valves without a return spring, such valves and their actuators can be built smaller and cheaper than conventional valves with a return spring.

List of reference symbols

1 hydraulic valve module

2 actuator power line

3 motor, actuator

4 hydraulic valve

5 valve spool

6 protective circuit

7 changeover switches

8 inrush current limiters

9 Charging circuit

10 power storage, energy storage

11 Status line

12 voltage converters

13 B atterymanagement

14 sensor

15 sensor cable

16 Data feed

17 Forwarding data

18 signal lines

19 Control

20 pilot control unit

21 External power supply

22 hydraulic lines

23 capacitor

24 accumulator

25 battery

26 Position marker, groove

27 locking element, locking spring

28 valve lock

29 Control hole

30 tax structures 31 position

32 electric motor

33 transmission

34 rack 35 gear

36 Switch-off position

37 supply channel

38 switches

39 Elevation profile 40 rising flank

41 profile height

Claims

Claims 1. Hydraulic valve module (1) having at least one hydraulic valve (4) with a valve slide (5), the valve slide (5) being adjustable with an electrical actuator (3) in order to connect hydraulic lines (22) through the hydraulic valve (4) To supply hydraulic fluid, the hydrau likventilmodul (1) has a controller (19) and an electrical energy store (10), the controller (19) and the electrical energy store (10) being set up to connect the valve slide (5) to the elec - Tric actuator (3) and in the electrical energy store (10) stored ter energy from every possible valve slide position in a switch-off position (36). 2. Hydraulic valve module (1) according to claim 1, wherein the controller (14, 15, 19) is designed as an emergency control and the electrical energy store (10) is designed as an emergency power supply and is configured to provide electrical energy for at least one emergency shutdown when in an external power supply (21) of the hydraulic valve module (1) a fault is detected, the emergency shutdown being set up to move the valve slide (5) from every possible valve slide position into the shutdown position (36) bring. 3. Hydraulic valve module (1) according to one of the preceding claims, wherein in the at least one hydraulic valve module (1) no mechanical return spring is arranged with which the valve slide (5) passively in a Shutdown position (36) can be brought. 4. Hydraulic valve module (1) according to one of the preceding claims, wherein the valve slide (5) has a position marker (26) which enables the switch-off position (36) to be found and / or the position of the valve slide to be calibrated. 5. Hydraulic valve module (1) according to claim 4, wherein the position marker (26) is a groove into which a latching element (27) can engage. 6. Hydraulic valve module (1) according to one of the preceding claims, wherein a plurality of hydraulic valves (4) and a common electrical energy store (10) belong to the hydraulic valve module (1) and the electrical energy store (10) is designed for a plurality of valve spools ( 5) from every possible valve slide position to the shut-off position (36). 7. Hydraulic valve module (1) according to claim 6, wherein the actuators (3) of the various hydraulic valves (4) and the electrical energy store (10) via an inrush current limiter (8) are connected to the external power supply (21) so that they are switched on one after the other can be. 8. Hydraulic valve module according to one of the preceding claims, wherein the electrical energy store (10) comprises at least one of the external power supply (21) chargeable electrical energy storage cell (23,24,25). 9. Hydraulic valve module (1) according to claim 8, wherein the electrical energy storage cell comprises at least one capacitor (23) and / or an accumulator (24). 10. Hydraulic valve module (1) according to one of claims 1 to 7, wherein the electrical energy storage cell comprises a battery (25). 11. Hydraulic valve module (1) according to one of the preceding claims, wherein the controller (19) and the electrical energy store (10) in one Pilot control device (20) of the at least one electrical actuator (3) are arranged, to which the external power supply (21) of the hydraulic valve module (1) is connected. 12. Hydraulic valve module (1) according to claim 11, wherein the pilot control device (20) has a protective circuit (6) and / or other common components for a plurality of hydraulic valves (4). 13. Hydraulic valve module (1) according to claim 11 or 12, wherein the pilot control device (20) has at least one sensor (14) with which the external power supply (21) can be monitored and the controller (19) in the pilot control device (20) to it is set up to perform an emergency shutdown if the sensor (14) detects a fault in the external power supply (21). 14. A method for the safe operation of a hydraulic valve (1) without mechanical cal return spring, wherein a valve slide (5) in the hydraulic valve (4) is moved by an electric actuator (3) and held in predeterminable positions, further in case of detection of an error in an external power supply (21) is automatically switched to an electrical energy store (10) of the hydraulic valve module and the valve slide (5) is moved into a safe, predeterminable switch-off position (36). 15. The method according to any one of claims 13 or 14, wherein the shutdown position (36) is determined by means of a position marker (26) on the valve slide (5). 16. A computer program product having commands which cause a hydraulic valve module according to one of claims 1 to 12 to carry out the method according to one of claims 13 to 15.