EP3350455A1

EP3350455A1 - Valve control means, and method for operating a valve control means

Info

Publication number: EP3350455A1
Application number: EP15766121.6A
Authority: EP
Inventors: Martin Maichl; Michael Berner
Original assignee: Festo SE and Co KG
Current assignee: Festo SE and Co KG
Priority date: 2015-09-15
Filing date: 2015-09-15
Publication date: 2018-07-25
Also published as: US20190049032A1; CN108026948A; CN108026948B; US10767779B2; WO2017045701A1

Abstract

The invention relates to a valve control means for electrical actuation of at least one valve drive (51a to 51h; 16), having a control circuit (28; 89; 109) which is configured to influence an electric energy flow between an electric source and the valve drive (51a to 51h; 116), and which comprises a bus interface (20) for communication with a superordinate control arrangement (2), and a sensor means (41, 42, 43, 44; 94; 111, 112) which is configured to determine a physical quantity of the energy flow which can be varied by electrical actuation of the valve drive (51a to 51h; 116), and is configured to provide the control circuit (28; 89; 109) with a sensor signal which is dependent on the determined physical quantity. It is provided according to the invention that the control circuit (28; 89; 109) is configured to determine a condition of the valve drive (51a to 51h; 116) using the sensor signal and at least one characteristic value of a physical variable from the group comprising energy flow duration, energy flow voltage, energy flow current, fluid pressure, and is configured to communicate the condition to the bus interface (20).

Description

Valve control and

Method for operating a valve control

The invention relates to a valve control for the electrical control of at least one valve drive, with a control circuit which is designed to influence an electrical energy flow between an electrical source and the valve drive and which comprises a bus interface for communication with a higher-level control arrangement and a sensor means for determining a variable by electrical actuation of the valve drive physical variable and for providing a dependent of the determined physical quantity sensor signal to the control circuit is formed. Furthermore, the invention relates to a method for operating a valve control.

From PCT / EP2013 / 003524 a valve arrangement for influencing at least one fluid flow is known which comprises a control device and at least one valve device, the control device having a bus interface for connection to a bus communication system for receiving movement commands, processing means for processing the movement commands in control commands for valve devices and at least one connection device for the electrical coupling of valve devices and wherein the at least one valve device electrically connected to one of the on closing devices of the control device is and a processing means comprises, which is designed for processing the control commands, wherein the processing means are associated with at least a first connection means for electrical coupling of valves and at least one second connection means for electrically coupling sensor means.

The object of the invention is to provide a valve control and a method for operating a valve control, which have an improved availability.

This object is achieved for a valve control of the type mentioned with the features of claim 1. It is provided that the control circuit for determining a state value for the valve drive based on the sensor signal and at least one characteristic of a physical variable from the group: energy flow duration, energy flow voltage, energy flow, fluid pressure, fluid volume flow, and is designed for providing the state value at the bus interface ,

The valve drive, which is provided for activation by the valve control, is preferably a piezoelectric drive or a magnetic drive. In both cases, the task of the valve control is to provide electrical charges from a source to the valve drive and optionally, depending on the configuration of the valve drive, in particular as a piezo drive, to dissipate these provided and stored there electrical charges again. This provision of electrical charges preferably takes place as a function of a movement signal which is generated either in the valve control or from the outside, in particular from a superordinate one Control device is provided to the valve control and is referred to as energy flow. For the further consideration of the valve control, it is assumed that the valve drive is either designed directly as a valve body, as may be the case in particular with a piezoelectric drive, or is motion-coupled to a valve body, in any case as a function of the energy flow provided on the basis of the movement signal to bring about a change in position for the valve body. As a result of this change in position, the valve body can influence a free cross section in a valve housing, in particular between a closed position and an open position, and thus set a fluid flow from an electrical source to a fluid consumer. The fluid consumer can optionally be a valve body of a main valve, so that in this case the valve drive is formed as part of a pilot valve, alternatively, the fluid consumer is an actuator such as a fluid cylinder, in particular pneumatic cylinder.

With the help of the state value, which is determined by the control device, a statement about a state of wear of the valve drive and / or the movement-coupled with the valve drive valve is possible, can be derived from the information such as a still expected service life for the valve drive or the valve. With the condition value, which may be dimensioned (one or more SI units) or dimensionless, a precautionary replacement of the valve drive or valve should optionally be carried out or at least prepared before the failure of the valve drive or the valve occurs. As a result, the desired improvement in the (temporal) achieved availability of the fluidic system formed from the valve control and the associated valve. The state value can be displayed directly on an output device of the valve control, for example an optical display such as a warning light or an alphanumeric display. It is preferably provided that the state value, in particular when exceeding a predefinable threshold, is provided via the bus interface to a higher-level control device, which is usually equipped with an output device such as a display or screen. Additionally or alternatively it can be provided that the state value is provided wirelessly, in particular via an optical or electromagnetic transmission link to a portable user terminal such as a mobile phone or a portable computer.

It is particularly advantageous in the case of the valve control according to the invention that the state value is determined on the basis of physical variables which are directly related to the operation of the valve drive.

On the basis of an exclusive evaluation of sensors, in particular displacement measuring devices or limit switches, which are mounted on a fluid operable actuator, which is controlled by means of the provided with the valve actuator valve and the associated valve control, could also at least statements about a number of cycles for the valve drive and possibly be made about a state of aging of the valve. However, this can only be indirect statements about the actual wear on the valve drive or valve, while the determination of the state value direct statements about the Bean- spruchung and the aging or wear of the valve drive are possible.

This is due in particular to the fact that, in addition to the signal of the sensor means, at least one further physical variable such as the energy flow duration and / or the energy flow voltage and / or the energy flow stream and / or a fluid pressure is included at a valve inlet connection or a valve outlet connection in order to determine the state value, in order to enable direct statements about the electromechanical load of the valve drive. It is particularly advantageous if the sensor means likewise determines a physical quantity and converts it into a sensor signal which is directly related to the actuation of the valve drive. By way of example, it is provided that the sensor means for determining at least one further physical quantities from the group: energy flow time and / or energy flow and / or energy flow and / or fluid pressure and / or fluid flow or a stroke of the valve drive and / or a movement speed of the valve drive and / or an acceleration of the valve drive, is formed, so that the state value of at least two physical quantities of the aforementioned group is determined. By way of example, the state value can be determined from a combination of energy flow duration and energy flow current or from a combination of energy flow duration and energy flow voltage or from a combination of energy flow duration and fluid pressure or other at least pairwise combinations of physical quantities.

In this case, the energy flow duration is that, in particular accumulated, time span within which an electrical charge flow from an electrical source to the valve drive or from the valve drive to the electrical source. The energy flow voltage is in particular the electrical voltage with which the electric charge flow is provided to the valve drive. For example, in an embodiment of the valve drive as a piezo actuator, in particular at a constant energy flow current, a voltage difference between a charge onset and a charge end for the piezoactuator can be considered. The energy flow stream is that electric current that flows between the electrical source and the valve drive, wherein in the case of an embodiment of the valve drive as a piezoelectric drive and a current direction is considered, as it is either a charging process or a discharge process for the piezoelectric actuator. In one embodiment of the valve drive as a piezo actuator may also be considered, over which period of time the piezoelectric actuator was applied to which electrical voltage, since a more refined assessment of a state of wear of the valve drive is made possible. From a consideration of the fluid pressure, in particular at a valve inlet port or a valve outlet port, a conclusion can be drawn on a static and / or a dynamic load of the valve drive, which can also be included in the determination of the state value. In this case, in particular a pressure level of the fluid pressure is of interest, which possibly acts on the valve drive for a longer or lasting period or against which the valve drive must hold the valve body in a valve position predetermined by the movement command. By way of example, the control device is associated with two differently configured sensor means which are each designed to determine a characteristic value of a physical variable. Alternatively it can be provided that only one sensor means is used for the actual measurement of a physical quantity, while the at least one characteristic of at least one physical quantity is derived from a control signal resulting from the motion signal processed in the valve control. For example, it is not necessary to measure the energy flow time, since this can be specified by the control device, in particular taking into account an internal system clock of the control device, and need not be determined by a separate sensor device. In a similar manner, if appropriate with the acceptance of a possibly greater error, a characteristic value for the energy flow voltage and / or the energy flow stream, in particular with knowledge of the circuitry structure of the control device and the valve drive, can be provided solely on the basis of a control signal.

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

It is expedient if the control circuit for determining the state value for an evaluation of a time course of the sensor signal and / or a time profile of the at least one characteristic value, in particular for a determination of an extreme value or a gradient is formed. For this purpose, the control circuit comprises a computing unit in which the sensor signal and / or the characteristic value, preferably at regular time intervals, in particular based on an internal system clock, are detected and a comparison with temporally preceding levels of the sensor signal and / or the characteristic value to determine a maximum and / or minimum level of the sensor signal and / or the characteristic value and / or a determination of a maximum and / or minimum gradient of the sensor signal and / or the characteristic value to enable. Furthermore, the control circuit comprises a memory device in which temporally preceding levels of the sensor signal and / or the characteristic value and / or extreme values and / or gradients can be stored, in order to be able to draw conclusions about the state of the valve drive. By way of example, it may be provided to store one or more characteristic values in the memory device that were determined in a new state of the valve drive and that can later be used as the basis for a comparison with current characteristic values.

In a further embodiment of the invention, it is provided that the control circuit in addition to the bus interface comprises a sensor interface for a direct connection of the sensor means and an electric power amplifier for an immediate control of the valve drive.

The sensor interface may be formed as an analog interface, so that a sensor means can be connected, which provides only an analog signal. Such a sensor means may be, for example, a limit switch (position transmitter) or a resistive displacement measuring system. It is preferably provided that only exactly one type of communication and no conversion of the sensor signal are provided between the sensor means and the control circuit. In particular, no analog / digital conversion takes place along a transmission path between sensor means and control circuit, but rather the control circuit is optional for one formed directly processing of the provided analog signal or for an internal analog / digital conversion of the provided analog signal.

If the sensor means is designed for a digital transmission of the sensor signal, no additional conversion of the sensor signal, in particular in the sense of a digital / analog conversion or a digital / digital conversion, takes place between the sensor means and the control circuit. Rather, the sensor interface is formed in this case as a digital interface, which is designed for direct coupling of the digital sensor signal. Accordingly, the sensor interface is adapted to the digital communication protocol of the sensor means.

By means of this direct coupling of the sensor means to the control circuit, couplings of undesired external disturbing influences and / or time delays in the transmission of the sensor signal from the sensor means to the sensor interface are minimized.

The task of the electric power amplifier is to convert a control signal provided by the control circuit into a temporary release of the energy flow between the source and the valve drive. Preferably, the electrical output stage is an electronic switch, in particular a field effect transistor (FET). The electrical output stage is preferably arranged in an immediate vicinity of the control circuit, in particular on the same circuit board as the control circuit. In this way, a transmission of the drive signal without complex protective measures can be made reliable, without this interfering with the outside play a significant role. special It is preferably provided that the electrical output stage is implemented as part of an integrated circuit, which also includes the control circuit. This integrated circuit is preferably realized as an ASIC (application-specific in tegrated circuit) on a single silicon component, so that the control circuit and the output stage (s) are adapted exactly to the required application and as few, in particular no, unnecessary or unnecessarily large dimensioned circuit components exhibit.

The control circuit is preferably associated with an electrical output stage with integrated sensor means for direct actuation and condition monitoring of the valve drive. In this case, provision is made in particular for the electrical output stage to include the sensor means. In this case, ei ne internal communication between the control circuit and Endstu Fe is formed in a bidirectional manner, on the one hand to transmit the control signals from the control circuit to the power amplifier and on the other hand, the sensor signals from the power amplifier to the control circuit. It is particularly advantageous if the electrical output stage is implemented as part of an integrated circuit, which also includes the control circuit, in particular as an ASIC.

It is advantageous if the electrical output stage is designed as a high-voltage driver stage for driving a piezoelectric actuator. This makes it possible to realize a highly integrated control circuit with condition monitoring for the connected piezo actuators.

It is particularly advantageous if the electrical end stage (s) is formed together with the control circuit as a one-piece, integrated circuit. It is expedient if the control circuit is set up in the determination of the state value for inclusion of a communication signal provided at the bus interface, in particular a position signal of a position sensor, which is designed for determining a position of an actuator. The bus interface can be provided as a bus bus interface for a, preferably digital, in particular bidirectional, communication of the control circuit with external components. These external components may be a higher-level control device and / or other bus subscribers, in particular control circuits, and / or position sensors. Optionally, it can be provided that the control circuit is electrically connected to the bus interface via an internal communication platform and a communication protocol is used for the internal communication between the control circuit and the bus interface, which deviates from a communication protocol with which external components communicate with the bus interface , By way of example, it is provided that the control circuit is connected to the bus interface via an SPI interface (Serial Peripheral Interface). In this case, it is preferably provided that the control circuit is designed as a "slave" and the bus interface as a "master". It is particularly preferably provided that the bus interface is a processing device for processing external bus signals, which can be provided in particular by a higher-level control device via a bus, and for processing internal bus signals, for example according to the SPI communication protocol. By way of example, it can be provided that the processing device analyzes incoming external bus signals for the presence of motion commands and converts these into control commands which are transmitted via the internal communication system. Protocol are provided to the control circuit, where finally carried out a conversion into the motion signals for the valve actuators.

It is preferably provided that the sensor means is designed for determining a position of the valve drive or for determining a position of a main valve which is fluidically coupled to a pilot valve formed by the valve drive. In an embodiment of the sensor means for determining a position of the valve drive can be provided that the sensor means determines an electrical variable such as an electrical voltage or an electric current, which are provided to the valve drive or that the sensor means movement or deformation of the valve drive Determined based on an electromechanical measuring principle. In an embodiment of the sensor means for determining a position of a pilot control valve or main control valve motion-coupled to the valve drive, an electromechanical (electrical resistance path, potentiometer) or electromagnetic (Hall sensor) measuring principle is preferably used, in which a movement of a valve body of the pilot valve or main valve is converted into an electrical measurement signal. In the same way, in the case of an embodiment of the sensor means, this applies to a determination of a position of a main valve which is fluidically coupled to a pilot control valve that can be activated by the valve drive. This is practically interposed between the pilot valve and the main control valve, a fluidic transmission path, which thus flows into the sensor signal of the sensor means with and accordingly also part of the monitoring function by the control circuit. In a further embodiment of the invention, it is provided that the control circuit comprises a memory means in which state values and / or sensor signals and / or characteristic values are stored, in particular timestamps, and in that the control circuit is for a comparison of current state values and / or sensor signals and / or characteristic values with stored state values and / or sensor signals and / or characteristic values is formed. It is preferably provided to provide determined state values and / or sensor signals and / or characteristic values for a time-dependent processing in the control circuit with a time stamp, this time stamp can be fixed, for example, to an internal system clock of the control circuit, so that a unique temporal assignment of stored values is possible. The time stamp enables a statement as to when the respective characteristic value was determined, in order to enable as exact a calculation of the state value on the basis of the time difference with more recent or current characteristic values.

The object of the invention is achieved by a method as indicated in claim 10. In this case, the following steps are provided: temporary release of an electrical energy flow between an electrical source and a valve drive by a control circuit as a function of a movement signal, determination of a physical quantity of energy flow between the source and valve drive by means of a sensor means and provision of one of the determined physical quantity dependent sensor signal to the control circuit, determination of a state value for the valve drive based on the sensor signal and at least one characteristic of a physical variable from the group: energy flow duration, energy flow voltage, energy flow stream, fluid pressure (fluid inlet pressure, fluid output pressure) in the control circuit and providing the state value to a bus interface associated with the control circuit.

In a further embodiment of the method, it is provided that an evaluation of a time profile of the sensor signal and / or a time profile of the at least one characteristic value, in particular a determination of an extreme value or a gradient, in the control circuit is performed for the determination of the state value.

In a further refinement of the method, it is provided that the control circuit for determining the state value carries out a query of signal inputs at a bus interface which is designed for communication with a superordinate control device and at a sensor interface which is designed for a direct connection of a sensor means ,

In a further refinement of the method, provision is made for the control circuit to take into account, when determining the state value, a position signal of a position sensor provided on the bus interface, which is designed to determine a position of an actuator.

In a further embodiment of the method, it is provided that a determination of a position of the valve drive or a determination of a position of a main valve, which is coupled fluidically with a pilot valve formed by the valve drive, is performed with the sensor means.

In a further embodiment of the method it is provided that the control circuit a comparison of, in particular provided with time stamps, state values and / or sensor sensor len and / or characteristic values with current state values and / or sensor signals and / or characteristic values is carried out and provides a diagnostic signal at the bus interface in the presence of a presettable deviation.

An advantageous embodiment of the invention is shown in the drawing. Showing:

Figure 1 is a schematic representation of a fluidic

System comprising a higher-level control device, a higher-level and a lower-level bus communication system and a valve arrangement comprising a control device and a valve device, as well as a plurality of actuators and arranged sensors,

FIG. 2 shows a detail view of FIG. 1 with an alternative coupling of the valve arrangement to the higher-level bus communication system,

3 is a schematic representation of a valve arrangement comprising eight independently controllable piezo valves and four of the piezo valves pneuma table controllable main valves,

Figure 4 is a perspective view of a concrete

Embodiment of the valve arrangement shown in Figure 3,

Figure 5 is a planar, schematic detail of a

Sensor means of Figure 4

Figure 6 is a schematic functional representation of a second embodiment of a valve device, and Figure 7 is a planar, schematic functional representation of a third embodiment of a valve device.

A fluidic system 1 shown schematically in FIG. 1 comprises a higher-order control device 2, a higher-level bus communication system 3, a bus coupler 4, a subordinate bus communication system 5, a valve arrangement 6 and several actuators 7, 8, external actuators 9 to 8 associated with the actuators 7, 8 12 and input / output modules 15, 16.

Such a fluidic system 1 can be used, for example, in a complex processing machine not shown in detail for automation purposes, for example, to temporarily clamp or transport not shown workpieces with the help of the actuators 7, 8. In order to coordinate the individual processes in such a processing machine, a higher-level control device 2 designed, for example, as a programmable logic controller (PLC) is provided, which is connected to a higher-level bus communication system 3 in order to be able to communicate with a large number of bus users. The bus subscribers are, for example, an unillustrated motor controller for controlling electric drive motors (also not shown) or bus couplers 4, which are designed to integrate complex subcomponents such as the valve arrangement 6 into the fluidic system 1. Such complex subcomponents may operate with an independent internal bus communication protocol independent of the bus communication protocol of the parent bus communication system 3 in order to be able to address a plurality of bus subscribers within the subordinate bus communication system 5. While it If the higher-level bus communication system 3 is typically a fieldbus system according to one of the usual fieldbus standards, the subordinate bus communication system 5 is typically a proprietary bus communication protocol tailored to the needs of the bus subscribers of the subordinate bus communication system 5.

In the present case, for reasons of simplified drawing, only a single bus subscriber formed as a valve arrangement 6 is connected to the subordinate bus communication system 5, the structure and mode of operation of which will be explained in more detail below. The valve arrangement 6 comprises a control device 17 and a valve control designated as a valve device 18. By way of example, it is provided that the control device 17 and the valve device 18 are structurally separated from each other and are accommodated in housings, not shown. In this case, the control device 17 is used to control a plurality of valve devices 18, of which, for reasons of clarity, however, only one is shown. Between the control device 17 and the valve device 18, a communication connection is provided, which is realized by way of example by means of a connection cable 19. The communication connection can be designed, for example, as digital, serial data communication, in particular according to the SPI standard (Serial Peripheral Interface) for bidirectional communication between the control device 17 and the valve device 18.

The control device 17 is designed as an electronic circuit and has a plurality of electronic components which are arranged on a printed circuit or printed circuit board. The electronic grinder described in more detail below Components are essential to the functional scope of the control device 17, further electronic and electrical components not described in detail below serve as peripherals and ensure, for example, the electrical supply and the internal and external electronic communication of the electronic components described below. By way of example, it is provided that the control device 17 comprises an electronic communication module 20 as a bus interface, which is provided for receiving, processing and forwarding data, which are provided via the subordinate bus communication system 5. For this purpose, the communication module 20 is connected by way of example both to the bus coupler 4 and to the input / output module 16, which is designed for connection to the subordinate bus communication system 5. The electronic communication module 20 can then use the subordinate bus communication system 5 to check whether this data is optionally intended for the control device 17. Furthermore, the electronic communication module 20 may output data to the subordinate bus communication system 5, for example, to transmit status messages about the function of the control device 17 and associated components to the control device 2. Furthermore, it can be provided that the electronic communication module 20 can also pass on data to other subscribers of the subordinate bus communication system 5, which are provided for influencing, in particular controlling or parameterizing, these further bus communication subscribers. If the communication module 20 can derive information which is sent via the subordinate bus communication system 5 and which is directed to the control device 17, it can forward this information to a processing device 21. By way of example, the processing device 21 is embodied as a computing unit, in particular in the form of a microcontroller or microprocessor, and comprises a memory device (not shown). The task of the processing device 21 is to process data which are provided on the one hand by the electronic communication module 20 and on the other hand are provided by connection devices 22 - 25 and valve devices 18 connected thereto. An essential task of the processing device 21 is to isolate motion commands from the data transmitted via the subordinate bus communication system 5 and provided by the communication module 20, which describe a specific movement of an actuator 8 which is to be controlled by the valve device 18. When such a movement command is received, it is provided that the processing device 21 first determines the current status of the actuator 8. This is done, for example, via the fact that sensor signals from external sensor devices as well as from sensor means associated with the valve device 18 are processed in the processing device 21.

Based on this determination of the current state of the connected actuator 8, the processing device 21 can create a movement profile for the connected actuator 8 in a downstream working step, which is then provided to the at least one valve device 18. The movement profile is, for example, a specific specification for a temporal movement sequence of the connected actuator 8, which is converted in the valve device 18 into control signals for releasing the corresponding fluid flows which are released by the individual valves connected to the valve device 18 and the actuator 8 should be made available. Preferably, at least one control algorithm is stored in the non-illustrated memory device of the processing device 21, with the aid of which a control of the actuator 8, in particular a position control, can be performed. In this case, the at least one stored control algorithm can preferably be parameterized in order to adapt it to the properties of the connected actuator 8. For this purpose, the processing device 21 can be addressed via the subordinate bus communication system 5 with the aid of the electronic communication module 20 and the bus coupler 4 via a suitable input device which is connected to the bus coupler 4. The input device is, for example, a personal computer, in particular a laptop. It is particularly advantageous if the bus coupler 4 and / or the processing device 21 comprise a web browser which according to a predetermined protocol provides a user interface for the connected input device, in particular in the form of an input mask for the parameters in question.

Furthermore, the control device 17 comprises at least one pressure sensor, in particular a supply pressure sensor 26 and an ambient pressure sensor 27. The supply pressure sensor 26 is connected in a manner not shown with a fluidic supply line, which is provided for providing fluid flows to the valves, not shown, with the Valve device 18 are connected. The ambient pressure sensor 27 has the task of determining an ambient pressure in the surroundings of the control device 17. By way of example, provision is made for the supply pressure sensor 26 and the ambient pressure sensor 27 to be designed as absolute pressure sensors, so that a pressure measurement is compared with an internal pressure sensor. vacuum is performed in the respective pressure sensor. This is particularly advantageous if the valve device 18 is equipped with absolute pressure sensors described in more detail below.

The valve device 18, also shown diagrammatically in FIG. 1, comprises as a central component a processing means 28 which is designed as a computer unit, in particular a microcontroller or a microprocessor and which is arranged on a printed circuit board 29. By way of example, the printed circuit 29 is manufactured as a printed circuit board with electrical interconnects not shown in detail from a flexible composite material and can therefore be bent, for example, at 90 degrees to the bending edges 30 and 31, to ensure an advantageous integration in a valve module described in more detail below. By the intended bending edges 30 and 31, the printed circuit 29 is divided into three areas 32, 34, 35, wherein also a different division can be selected or can be dispensed with a bending of the printed circuit 29.

By way of example, a connection region is formed in the first region 32 of the printed circuit, which comprises a plurality of electrically conductive connection contacts 33, which are provided for an electrical connection with valves, not shown. In the second area, the processing means 28 is arranged with an electrical and optionally electronic periphery (not shown in detail), wherein this periphery may in particular be electrical and electronic components such as resistors, capacitors or integrated circuits. By way of example, in the second region 34, an electrical output stage arrangement 38 is also provided, which is electrically coupled to the processing means 28 and which, when exposed to electrical signals. nals provided by the processing means 28 corresponding electrical power to the respective terminals 33 to electrically control the associated, not shown, valves.

In the third region 35 of the printed circuit 29, two pressure sensors 36, 37 are arranged, which are preferably designed as absolute pressure sensors and which are designed for determining a fluid pressure, in particular at a working output of a valve module. Further, in the third region 35 electrical connections 40 are provided for position sensors, not shown, with which, for example, the position of pneumatically piloted main valves can be determined.

The processing means 28 are designed for communication with the processing device 21 via a conductor-connected, exemplarily wired, communication connection 39. The communication connection 39 is guided via the connection cable 19 to one of the connection devices 22 - 25 of the control device 17. Preferably, the communication link 39 is bidirectionally performed between processing means 28 and processing means 21 according to the SPI protocol. In this case, the processing means 28 can in particular receive control commands of the processing device 21 in order to implement them locally on site by appropriate processing, in particular using stored or permanently programmed algorithms, into control signals for the valves connected to the connection contacts 33, not shown. Furthermore, the processing means 28 are for processing sensor signals received from the pressure sensors 36 and 37 and from the position sensors, not shown, which are connected to the electrical connections 40. are closed, provided, trained. In this way, for example, a pressure control for the valves based on the signals of the pressure sensors 36 and 37 and / or a position control for the valves based on the signals of the position sensors connected to the electrical terminals 40 are performed by the processing means 28, in a corresponding control of the results in the connection contacts 33 connected, not shown valves results.

The sensor signals provided by the connected sensors, in particular the pressure sensors 36, 37 and the position sensors at the terminals 40, can also be provided as raw data or raw signals via the communication link 39 to the processing device 21 in addition to the immediate processing in the processing means 28. The processing device 21 is designed in such a way that it can also use control algorithms on the basis of such raw data or raw signals, possibly together with sensor signals from external sensor devices 9, 10, which are provided via the subordinate bus communication system 5, in order, for example, to control the position of one of the connected actuators 7 or 8 make. In this case, the position sensors 9 to 12 are arranged by way of example both on the actuator 7 and on the actuator 8, which are each provided by way of example for determining a position of a piston 45 or 46 of the actuators 7, 8 designed as pneumatic cylinders. The position sensors 9 and 10 are coupled via an external input / output module 15 to the higher-level bus communication system 3. Accordingly, the position signals of these position sensors 9 and 10 via the higher-level bus communication system 3, the bus coupler 4 and the subordinate bus communication system 5 and the Communication module 20 transmitted to the processing device 21. On the other hand, the position sensors 11 and 12 are connected to the internal input / output module 16, which communicates directly with the communication module 20 via the subordinate bus communication system 5, whereby a particularly short signal propagation time between the sensors and the processing device 21 can be ensured.

FIG. 2 provides an alternative connection for the valve arrangement 6, in which a direct communication between the control device 2, the valve arrangement 6 and the input / output module 15 is provided. For this purpose, it is provided to modify the electronic communication module 20 according to FIG. 1 such that a direct communication between the control device 2 and the valve arrangement 6 is made possible. This structure is preferable if no variability is necessary for the fluidic system with regard to the selection of the bus communication protocol, but the valve arrangements 6 are always connected to the same superordinate bus communication system 3.

FIG. 3 shows an exemplary application for a valve arrangement 6 shown in FIG. The valve assembly 6 is electrically connected to a valve disc 50 and provided for the electrical control of exemplary eight piezo valves 51a to 51h. The piezo valves 51a to 51h are each electrically connected in a manner not shown with the terminal contacts 33 of the valve assembly 6 shown in Figure 1 and can thus be supplied individually by the processing means 28 with electrical energy. By way of example, it is provided in the embodiment according to FIG. 3 that in each case two of the Piezoventile 51a to 51h are housed in a common receiving slot 52a to 52d, wherein in each of the receiving slots 52a to 52d a specifiable pneumatic pressure level is present, which provided by each accommodated in the corresponding receiving shaft 52a to 52d piezo valves 51a to 51h can be released at connection points 53a to 53h. The receiving wells 52b and 52c are provided for admission with a supply pressure provided by a pneumatic source 54. The two receiving wells 52a and 52d, however, are communicatively connected to the ambient pressure and serve for the removal of pressurized fluid. Preferably, a first connection point 53a with a third connection point 53c and a second connection point 53b with a fourth connection point 53d are pneumatically connected and each form a working connection 55a or 55b. Furthermore, a fifth connection point 53e with a seventh connection point 53g and a sixth connection point 53f with an eighth connection point 53h are pneumatically connected and each form a working connection 55c or 55d. Thus, either a supply pressure or an ambient pressure can be applied to the working ports 55a to 55d.

The working ports 55a to 55d are each connected by way of example to pneumatically pilot-controlled main valves 56a to 56d in order selectively to switch these main valves 56a to 56d, which are designed as 2/2-way valves, between a first and a second switching position, thereby selectively providing or discharging allow pressurized fluid to or from a fluidic consumer, not shown, which can be connected to output terminals 74a, 74b. By way of example, it is provided that each of the working ports 74a, 74b is assigned a respective pressure sensor 36 or 37 in order to be able to give the processing means 28 of the valve device 18 electrical pressure signals via the pressure levels respectively present at the working ports 74a, 74b. Further, each of the main valves 56a to 56d is assigned a position sensor 41 to 44 configured to detect a switching position of the respective main valve 56a to 56d. In another embodiment, not shown, the pneumatically pilot-operated main valves in other

Switching configurations, in particular as 3/2 way valves, be designed as 5/2 way valves or as proportional valves.

FIG. 4 shows a practical embodiment of the valve disc 50 shown in FIG. 3, whose mechanical and fluidic structure is known from EP 2 549 125 A1, which is hereby incorporated in full, wherein for the sake of clarity a summary of the essential elements of the known valve disc is provided below he follows. Here, the reference numbers used in EP 2 549 125 A1 are adapted to the reference numerals of the present description of the figures.

The valve disc 50 includes a valve module 57 and a

Main valve module 58, both of which are exemplary square-shaped. On narrow sides 59, 60 of the valve disc 50 protrude in each case as a flat plug 61, 62 formed contact means, the tab 61 is electrically associated with the valve module 57 and the tab 62 electrically the main valve module 58. The main valve module 58 is penetrated by a plurality of recesses 63, 64, 65 aligned normal to the sectional plane of the illustration according to FIG in a series of several valve disks 50 through channels for fluid supply and fluid disposal for the main valves 56a to 56 d are formed. In the same way, the valve module 57 is penetrated by recesses which are provided for a fluid supply and disposal of the piezo valves 51a to 51h and which are not recognizable in FIG.

The valve module 57 is connected to the main valve module 58 by elastic locking tongues 66 which are formed on a connecting part 67 arranged between the valve module 57 and the main valve module 58. The locking tongues 66 have recesses 68 which are adapted to locking projections 69, 70 on the valve module 57 and to the main valve module 58 and which form a positive coupling with these locking projections 69, 70. The connecting part 67 is used in addition to the mechanical coupling of the main valve module 58 with the valve module 57 and the electrical coupling of the

Main valve module 58 associated, in Figure 5 schematically illustrated position sensors with the not shown in Figure 4 processing means 28 according to the figure 3. In addition, signals of the position sensors on the tab 62 can be provided. In the connection part 67, the third region 35 of the printed circuit 29 shown in FIG. 1 with the electrical connections 40 is preferably arranged in order to ensure simple electrical connection of the position sensors to the processing means 28.

On the narrow side of the valve module 57 facing away from the main valve module 58, the first region 32 of the printed circuit 29 shown in FIG. 1 is connected to the electrically conductive connection contacts 33 for the electrical supply Piezo valves 51a to 51h arranged. Between the first region 32 and the third region 35, the second region 34 of the printed circuit 29 extends, thereby enabling compact integration of the printed circuit 29 into the valve module 57. By way of example, it is provided that the three areas 32, 34 and 35 of the printed circuit are electrically and mechanically connected to one another with flexible circuit sections, so-called "flex prints." With the flat plug 61, the valve arrangement can be connected to a bus coupler, not shown, for communication be connected to a control device, also not shown.

From the sectional view of Figure 4, the structure of the valve module 57 and the main valve module 58 is shown in more detail. Four valve cartridges 72a to 72d are accommodated in receiving shafts 52a to 52d in a valve housing 71 of the valve module 57 by way of example, each of the valve cartridges 72a to 72d respectively comprising two piezo valves 51a to 51h.

In the main valve housing 73 four main valves 56a to 56d are arranged by way of example, which are designed for optionally providing a supply pressure or an ambient pressure at the output connections 74a, 74b.

In the schematic representation of Figure 5, a portion 80 of the circuit formed as a third portion 35 of the printed circuit 29 is shown in a planar view. This section 80 is penetrated by a bore 81 which is designed for a fluidic connection between one of the valves of the valve module 57 and one of the valves of the main valve module 58 and which is also shown in FIG. 4 for orientation purposes. At one of the Main surfaces of the portion 80 shown in Figure 5, a spiral-shaped conductor assembly 82 is formed, which communicates with non-illustrated electronic components on the circuit board 29 conductively connected and which is arranged at least substantially concentric with the bore 81. The helical conductor arrangement 82 serves as a detector coil for determining an axial position of the respective associated main valve 56a, 56b, 56c or 56d. A sensor device using a detector coil is disclosed in PCT / EP2012 / 003051, which is expressly incorporated by reference into this disclosure. With such a spiral conductor arrangement 82 integrated in the printed circuit board 29, a precise determination of the stroke position of the respective associated main valve 56a, 56b, 56c or 56d can be made on the basis of a cost-effective production method.

In a variant of the spiral-shaped conductor arrangement not shown in more detail, the bore is arranged in the edge region of the spiral-shaped conductor arrangement so that it is surrounded by only a few turns, in particular only by the last turn, of the spiral-shaped conductor arrangement, whereby one advantageous for certain measuring purposes and concentric Arrangement of the bore in the spiral conductor arrangement deviating measuring characteristic can be achieved.

A second embodiment, shown in FIG. 6, of a valve controller 88, which can be integrated into the fluidic system 1 instead of the valve apparatus 18, comprises a control circuit 89 and a power amplifier arrangement 90. By way of example, it is provided that the processing means 89 and the output stage assembly 90 are each formed as discrete integrated circuits, which are arranged on a common printed circuit 91 and electrically connected to each other.

In this case, the processing means 89 has a digital interface 92 for a bidirectional communication, in particular according to the SPI bus protocol, with the processing device 21 shown in FIG. 1 via the connection cable 19.

Furthermore, the processing means 89 has a sensor interface 93, which is designed for connection of an external sensor means 94. Purely by way of example, it is provided that the external sensor means 94 is designed as a current sensor, which is looped into a connection line 95 between the output stage arrangement 90 and a valve drive designed by way of example as a piezo valve 96. In this case, the electrical sensor signal provided by the sensor means 94, which may in particular be an analog signal, is provided directly to the sensor interface 93. It is preferably provided that the sensor means 94 is arranged on the same printed circuit 91 as the processing means 89 and the output stage arrangement 90.

It is further provided that the sensor signal in the processing means 89 is optionally further processed analog or digital, preferably a digital processing is provided. Furthermore, the processing means 89 comprises a computing unit 97, a memory means 98 and a clock generator 99. The computing unit 97 is provided for processing incoming sensor signals of the sensor means 94 and in this processing uses clock signals provided by the clock generator 99, for example ne analysis of temporal waveforms of the sensor signal to enable. In addition, the arithmetic unit 97 is designed to provide selected or all sensor signals and / or results of processed sensor signals based on the clock signals of the clock generator 99 with time stamps and to store in the memory means 98.

On the basis of the currently arriving sensor signals and the clock signals of the clock 99 and possibly taking into account stored sensor signals and / or results of processed sensor signals, the arithmetic unit 97 using a hard-coded or freely definable algorithm can determine a state value, a state of the in the form of the piezoelectric valve 96 connected valve drive plays. The determined state value can be stored in the storage means 98, it is preferably provided to provide the determined state value to the digital interface 92, so that it can be forwarded to the processing device 21. In addition, the arithmetic unit 97 is adapted to implement at the digital interface 92 incoming motion signals, which are also referred to as motion profiles and can be provided by the processing device 21, in control signals for the power amplifier assembly 90, via a signal interface to the power amplifier assembly 90, in particular in unidirectional Communication way to be provided. In addition or as an alternative, the arithmetic unit 97 can be designed to make provision of control signals to the output stage arrangement 90 on the basis of fixedly programmed or freely definable movement programs.

In addition, and therefore only shown in dashed lines, the processing means 88 can be provided with an additional 100 parts to be equipped. At this additional interface 100, an external sensor means 101, for example, a limit switch (position transmitter) for a position determination of a main valve by means of a sensor line 102 can be connected. A sensor signal provided by the external sensor means 101 may be taken into account in the determination of the state value in the processing means 89.

The valve device 108 shown in FIG. 7, like the valve device 88, is likewise designed as a valve controller and differs from the valve device 88 in that the processing means 109 and the output stage arrangement 110 are constructed on a common silicon carrier as an integrated circuit. The valve device 108 can be integrated into the fluidic system 1 instead of the valve device 18. Deviating from the output stage arrangement 90, the output stage arrangement 110 has an integrated current sensor 111 and an integrated voltage sensor 112, with which a voltage current characteristic for the valve drive 116 designed as a piezo valve can be determined directly in the output stage arrangement 110 and via a bidirectional internal communication connection 113 can be provided to the arithmetic unit 117 of the processing means 109. There, processing of the sensor signals of the current sensor 111 and of the voltage sensor 112 takes place in the same manner as already described in connection with the valve device 88, preferably taking into account the clock signal of the clock generator 119, to determine the state value and to provide the state value at the digital interface 114 In addition or as an alternative, sensor signals stored in the memory means 118, in particular with time stamps, may also be used in determining the supply voltage. Standing value to be included. It is preferably provided over a specifiable period of time, which is also referred to as the energy flow duration, to provide a predeterminable flow (energy flow stream) to the valve drive and to determine the electric voltage (energy flow voltage) at the valve drive 116 before and after the end of the time duration, thereby To be able to calculate state value.

In addition, and therefore only indicated in dashed lines, the processing means 108 may be equipped with an additional cut 120. At this additional interface 120, an external sensor means 121, for example a limit switch (position transmitter) for determining the position of a main valve by means of a sensor line 122 can be connected. A sensor signal provided by the external sensor means 121 may be taken into account in the determination of the state value in the processing means 109.

The output stage arrangements 90 and 110 are preferably designed as constant current sources and are provided in particular for the actuation of piezoactuators. Accordingly, the state value in knowledge of the constant current which is output by the respective output stage arrangement 90, 110 can preferably be determined by determining the energy flow duration, that is to say the time interval which can be determined on the basis of the clock signal or those time segments in which a charge transport from an electrical source, not shown to the valve drive or in the reverse direction is made. In addition, the processing means 89, 109 may be designed to determine time periods in which one or more predefinable, by corresponding electrical charging of the valve drive 96, 116 exceeded load threshold in order to be able to include this information in the calculation of the state value.

Claims

claims

A valve controller for electrically controlling at least one valve drive (51a to 51h; 116), comprising a control circuit (28; 89; 109) adapted to influence an electrical energy flow between an electrical source and the valve drive (51a to 51h; 116) and a bus interface (20) for communicating with a higher-level control arrangement (2) and a sensor means (41, 42, 43, 44; 94; 111, 112), which is used to determine a by electric actuation of the valve drive (51 a to 51 h; 116) of variable physical size and for providing a sensor signal dependent on the ascertained physical variable to the control circuit (28; 89; 109), characterized in that the control circuit (28; 89; 109) determines a state value for the valve drive (51a to 51h, 116) on the basis of the sensor signal and at least one characteristic of a physical quantity from the group: Energi flow duration, energy flow voltage, energy flow stream, fluid pressure, fluid volume flow, and is designed for providing the state value at the bus interface (20).

2. Valve controller according to claim 1, characterized in that the control circuit (28; 89; 109) for determining the state value for an evaluation of a time course of the sensor signal and / or a time course of the sensor least one characteristic value, in particular for a determination of an extreme value or a gradient is formed.

3. Valve controller according to claim 1 or 2, characterized in that the control circuit (28; 89; 109) in addition to the bus interface (20) has a sensor interface (40; 93) for a direct connection of the sensor means (41, 42, 43, 44; 94; 111, 112) and an electric output stage (38; 90; 110) for direct actuation of the valve drive (51a to 51h; 116).

4. Valve controller according to claim 1 or 2, characterized in that the control circuit (28; 89; 109) has an electrical output stage (38; 90; 110) with integrated sensor means (41, 42, 43, 44; 94; 111, 112). for immediate activation and condition monitoring of the valve drive (51a to 51h, 116).

5. Valve controller according to claim 3 or 4, characterized in that the electrical output stage (38; 90; 110) is designed as a high-voltage driver stage for driving a Piezoaktua- sector.

6. Valve controller according to claim 3, 4 or 5, characterized in that the electrical output stage (38; 90; 110) is formed together with the control circuit (28; 89; 109) as a one-piece, integrated circuit.

7. Valve controller according to one of the preceding claims, characterized in that the control circuit (28; 89; 109) in the determination of the state value for inclusion of a provided at the bus interface (20) communication signal, in particular a position signal of a position sensor (41, 42, 43, 44), for an investigation a position of an actuator (56a, 56b, 56c, 56d) is formed, is set up.

8. Valve controller according to one of the preceding claims, characterized in that the sensor means (41, 42, 43, 44; 94; 111, 112) for determining a position of the valve drive (51 a to 51 h, 116) or for a determination of a position a main valve (56, 56b, 56c, 56d) fluidly coupled to a pilot valve (52a, 52b, 52c, 52d) formed by the valve drive (51a to 51h; 116).

9. Valve controller according to one of the preceding claims, characterized in that the control circuit (28; 89; 109) comprises a memory means (98) in which state values and / or sensor signals and / or characteristic values provided in particular with time stamps are stored, and in that the control circuit (28; 89; 109) is designed for a comparison of current state values and / or sensor signals and / or characteristic values with stored state values and / or sensor signals and / or characteristic values.

10. A method for operating a valve control which is supplied with an electrical energy flow by a control circuit (28; 89; 109) in response to a predeterminable movement signal, comprising the steps of: temporarily releasing an electrical energy flow between an electrical source and a valve drive (51a to 51h; 116) by means of a control circuit (28; 89; 109) in response to a movement signal, determination of a physical quantity of the energy flow between source and valve drive (51a to 51h; 116) by means of a sensor means (41, 42, 43 , 44, 94, 111, 112) and provision of a physical to the control circuit (28; 89; 109), determining a state value for the valve drive (51a to 51h; 116) on the basis of the sensor signal and at least one characteristic of a physical variable from the group: energy flow duration, energy flow voltage, energy flow current, fluid pressure ( Fluid input pressure, fluid output pressure) in the control circuit (28; 89; 109) and provision of the state value at a bus interface (20) assigned to the control circuit (28; 89; 109).

11. A method for operating a valve control according to claim 10, characterized in that for the determination of the state value, an evaluation of a time profile of the sensor signal and / or a time course of the at least one characteristic value, in particular a determination of an extreme value or a gradient in the control circuit (28; 89; 109).

12. A method for operating a valve control according to claim 10 or 11, characterized in that the control circuit (28; 89; 109) for the determination of the state value, a query of signal inputs to a bus interface (20), which is for communication with a higher-level control device is formed and at a sensor interface (40, 93), which is designed for an immediate connection of a sensor means (41, 42, 43, 44, 94, 111, 112) performs.

13. A method for operating a valve control according to claim 12, characterized in that the control circuit (28; 89; 109) in the determination of the state value at the bus interface (20) provided position signal of a position sensor (41, 42, 43, 44), the one for a determination a position of an actuator (56a, 56b, 56c, 56d) is taken into account.

14. A method for operating a valve control according to claim 10, 11, 12 or 13, characterized in that with the sensor means (41, 42, 43, 44; 94; 111, 112) a determination of a position of the valve drive (51a to 51h; 116) or a determination of a position of a main valve (56a, 56b, 56c, 56d) fluidly coupled to a pilot valve (52a, 52b, 52c 52d) formed by the valve driver (51a to 51h; 116).

15. A method for operating a valve control according to claim 10, 11, 12, 13 or 14, characterized in that the control circuit (28; 89; 109) a comparison of, in particular special time stamped with, state values and / or sensor signals and / or Carrying characteristics with current States and / or sensor signals and / or characteristic values and provides a diagnostic signal at the bus interface (20) in the presence of a predeterminable deviation.