IO-link hub and method for operating an IO-link hub

Abstract

The IO-Link hub (1) according to the invention is designed to operate a plurality of standard actuators (2) and has an IO-Link interface (3) for connection to an IO-Link master (4), a plurality of outputs for connection to the standard actuators, and at least one first microcontroller (8) for communication with the IO-Link master and the standard actuators. Furthermore, there is provision for a second microcontroller (9), which is designed to control at least one standard actuator in the form of a solenoid valve or lift valve and to evaluate state data relating to the solenoid valve or lift valve.

Description

[0001] IO-Link hub and methods for operating an IO-Link hub

[0002] The invention relates to an IO-Link hub for operating a plurality of standard actuators with an IO-Link interface for connection to a 10-Link master and a plurality of outputs for connection to the standard actuators, as well as a method for operating an IO-Link hub.

[0003] An IO-Link master is a device specifically used in automation technology to connect and manage multiple IO-Link-enabled sensors and / or actuators. It employs a standardized communication protocol (IO-Link) for bidirectional communication between the sensors / actuators, which also includes their control. To enable communication between non-IO-Link-enabled sensors / actuators and the IO-Link master, so-called IO-Link hubs are used. The IO-Link hub acts as a central point, collecting signals from one or more conventional or digital sensors and actuators and forwarding them to the IO-Link master. This simplifies cabling and enables centralized data transmission, thereby increasing efficiency and flexibility in automation technology.In addition, the IO-Link hub enables the reading of diagnostic data and parameters of the connected devices and their configuration.

[0004] The invention is based on the objective of improving the control and / or diagnostic capabilities of an IO-Link hub.

[0005] According to the invention, this is solved by the features of claims 1 and 8.

[0006] The IO-Link hub according to the invention is designed to operate a plurality of standard actuators and has an IO-Link interface for connection to an IO-Link master, a plurality of outputs for connection to the standard actuators, and at least one first microcontroller for communication with the IO-Link master and the standard actuators. Furthermore, a second

[0007] NAS\14743\A_Apct microcontroller is provided, which is designed to control at least one standard actuator designed as a solenoid valve or lift valve and to evaluate status data of the solenoid valve or lift valve.

[0008] For the purposes of this invention, the term "standard actuators" refers to actuators that are not IO-Link capable.

[0009] The first microcontroller preferably uses a microprocessor from the Texas Instruments MSP430 family, which is characterized by its energy efficiency and versatility and is particularly suitable for applications requiring low power consumption. For controlling the standard actuators configured as solenoid valves or lift valves and for evaluating status data (diagnostics) of the solenoid valves or lift valves, the second microcontroller is specifically equipped with a microprocessor from the STMicroelectronics SMT32G family.

[0010] According to a preferred embodiment of the invention, the second microcontroller is connected to an output stage which includes a PWM module for PWM (pulse width modulation) control of the at least one connected solenoid valve or lift valve. If the standard actuator is designed as a switching valve, the switching valve can be controlled particularly energy-efficiently via PWM control. The PWM module can preferably be implemented by a transistor, in particular a field-effect transistor, which is controlled by a second transistor (in particular a field-effect transistor). This then enables the implementation of a high-side switch in which the switch is connected between the positive power line (in particular +24V) and the load, whereas in a low-side circuit the load is connected to ground.The implementation of a high-side switch enables improved output control and is therefore more versatile, making Class A or Class B operation possible in particular.

[0011] In a further embodiment of the invention, the second microcontroller is connected to an output stage which includes a load detection module for

[0012] NAS\14743\A_Apct includes the detection of a solenoid valve or lift valve connected to one of the outputs. During load diagnostics, the output can be supplied with an output voltage below 1V and a minimum current of less than 300pA, thereby detecting whether a load (standard actuator) is connected to the output without having to switch the load. In the tests and calculations underlying the invention, loads up to 12kΩ at the output can be detected. For example, a connected solenoid valve can be identified by measuring and evaluating the coil resistance of the associated coil from the IO-Link hub.

[0013] Furthermore, the output stage connected to the second microcontroller can include a current measurement and diagnostic module for measuring the current of the standard actuators connected to the outputs, in particular solenoid or lift valves, and for evaluating current measurement signals. The current measurement and diagnostic module specifically includes a shunt resistor located after the load. The shunt resistor is connected to an integrated circuit specifically designed for current measurement, which preferably operates with a fixed gain. The integrated circuit is advantageously designed such that not only the current but also the output voltage can be measured, and it is possible to generate different error signals for voltage and current.If the integrated circuit for current and voltage measurement is connected to the second microcontroller, the error signal can be provided to the user either visually (e.g. with LEDs) or digitally.

[0014] To prevent mutual interference between the two microcontrollers, the first and second microcontrollers are galvanically isolated from each other. However, a half-duplex connection exists between the two microcontrollers, allowing communication in both directions. This enables the outputs of the IO-Link hub to be controlled from the IO-Link side, and conversely, diagnostic information to be displayed on the IO-Link side.

[0015] NAS\14743\A_Apct According to a preferred embodiment of the invention, the second microcontroller is designed to control a solenoid valve configured as a switching valve. For such solenoid valves, pulse width modulation by the PWM module results in particularly energy-efficient control, as will be explained in more detail below with reference to Fig. 3.

[0016] To expand its application possibilities, the IO-Link hub is designed for both Class A and Class B operation. While Class A operation uses a 3-pin connection for 24 V and up to 500 mA, Class B operation requires an additional power source for sensors / actuators with higher current draw (up to 2 A).

[0017] The inventive method for operating an IO-Link hub is characterized by the following method steps:

[0018] - Establishing a connection between the IO-Link hub and an IO-Link master,

[0019] - Establishing a connection between the IO-Link hub and at least one standard actuator designed as a solenoid valve or lift valve,

[0020] - Providing a communication interface by means of a first microcontroller for communication with the IO-Link master and at least one standard actuator and

[0021] - Providing a second microcontroller to control at least one solenoid valve or lift valve and to evaluate status data of the solenoid valve or lift valve.

[0022] The method according to the invention is particularly suitable for operating the IO-Link hub described above, wherein a switching valve is preferably used as the solenoid valve, which is controlled via the second microcontroller by means of dynamic pulse width modulation.

[0023] NAS\14743\A_Apct Furthermore, a timer mode can be provided in which the IO-Link hub controls at least one connected solenoid valve in adjustable opening and closing cycles. The on-time and off-time can be set. It can also be configured whether the cycle starts in the open or closed state.

[0024] Another function can be to count the switching cycles for each connected solenoid valve or lift valve and generate an output signal when a predetermined limit of switching cycles is reached.

[0025] Another very helpful feature is the inclusion of LEDs on the IO-Link hub. These LEDs can be controlled to easily locate a specific IO-Link hub within a network of multiple hubs. Furthermore, the LEDs can indicate the status of connected standard actuators (2) on the IO-Link hub (1). Different operating states (e.g., a malfunction or switching state of a connected standard actuator, IO-Link communication status, power status) can be displayed using different colors (e.g., green, yellow, red, etc.) and / or different LED behaviors (e.g., slow or fast blinking, continuous illumination, or an on / off state).

[0026] Furthermore, the switching time for activating and deactivating a connected solenoid valve / lift valve can be determined and evaluated. By observing the shift in the monitored current, it is possible to measure how long it took for the valve to switch from the applied voltage to the output, thus diagnosing the coil.

[0027] In a further embodiment of the invention, the switching of the connected solenoid valve / lift valve can be determined and evaluated based on the current flowing to the solenoid valve / lift valve. Continuous current monitoring allows the condition of the solenoid coil to be monitored in order to trigger an alarm in the event of a short circuit or open circuit.

[0028] NAS\14743\A_Apct Finally, it is possible to determine and evaluate the power consumption of the connected solenoid valve / lift valve.

[0029] Of course, the second microcontroller can also be designed to collect and evaluate additional data if desired in certain applications.

[0030] Further embodiments of the invention are explained in more detail below with reference to the following description and the drawing.

[0031] The drawing shows:

[0032] Fig. 1 shows a block diagram of the IO-Link hub according to the invention.

[0033] Fig. 2 shows a block diagram of the output stage and

[0034] Fig. 3 shows a diagram illustrating the control of a switching valve in PWM mode.

[0035] Fig. 1 shows a block diagram of the IO-Link hub 1 according to the invention for operating a plurality of standard actuators 2 with an IO-Link interface 3 for connection to an IO-Link master 4 and a plurality of outputs 5a, 5b, 5c, 5d for connection to the standard actuators 2. The connection between the IO-Link hub 1 and the IO-Link master 4 is made via an IO-Link cable 6. The standard actuators 2 are connected to the outputs 5a, 5b, 5c, 5d via two-wire standard cables 7.

[0036] The IO-Link hub also includes a first microcontroller 8 for communication with the IO-Link master 4 and the standard actuators 2. This can, for example, be an MSP430 microcontroller from Texas Instruments. Furthermore, a second microcontroller 9 is used to control the connected standard actuators 2 and evaluate their status data. The SMT32G microprocessor family from STMicroelectronics has proven particularly suitable for this purpose.

[0037] Of the standard actuators connected to NAS\14743\A_Apct, at least one is designed as a solenoid valve or a lift valve. However, it is also conceivable to connect different standard actuators.

[0038] The second microcontroller 9 is connected to an output stage 10, which is shown in more detail in Fig. 2 and may include one or more of the following modules: a PWM module 11 for pulse width modulation (PWM control) of the at least one connected solenoid valve or lift valve and / or a load detection module 12 for detecting a solenoid valve or lift valve connected to one of the outputs 5a, 5b, 5c, 5d and / or a current measurement and diagnostic module 13 for measuring the current of the solenoid or lift valves connected to the outputs 5a, 5b, 5c, 5d and for evaluating current measurement signals.

[0039] The first microcontroller 8 and the second microcontroller 9 are galvanically isolated from each other via an electrically non-conductive coupling element 14 in order to avoid electrical conduction between the two microcontrollers 8, 9, but to allow the exchange of signals 15.

[0040] The IO-Link hub 1 is also equipped with LEDs 16, which can be used to display various information. For example, an IO-Link hub 1 can be more easily located in a network of multiple hubs by activating one of its LEDs 16. The LEDs can also indicate the status of standard actuators 2 connected to the IO-Link hub 1. Different operating states (e.g., a malfunction or...) can be indicated by different colors (e.g., green, yellow, red, etc.) and / or different LED activation patterns (e.g., slow or fast blinking, continuous illumination, or being switched on or off).

[0041] NAS\14743\A_Apct displays the switching state of a connected standard actuator, IO-Link communication status, and power status.

[0042] The IO-Link hub 1 is designed for both Class A and Class B operation. In Class A operation, the IO-Link hub 1 is connected to the IO-Link master 4 via a 3-wire IO-Link cable, so that the first microprocessor 8 receives power via this connection and a first voltage regulator 17. The second microprocessor 9 requires a power supply via an external power source 21 and a second voltage regulator 18. This allows, in the illustrated embodiment, a maximum load of 8 A and thus the required 2 A per output 5a, 5b, 5c, 5d. The external power source 21 could also be daisy-chained to another IO-Link hub, as the cable 20 itself can handle up to 16 A.

[0043] In Class A operation, the IO-Kink Hub 1 is connected to the IO-Link Master 4 via a 5-wire IO-Link cable, so that the first microprocessor 8 receives power via this connection and a first voltage regulator 17. The second microprocessor 9 is powered from the IO-Link Master 4 via a power connection 19 and the second voltage regulator 18. This allows, in the illustrated embodiment, a maximum load of 2A and thus the required 0.5A per output 5a, 5b, 5c, 5d.

[0044] A switching valve is particularly preferred as the solenoid valve. According to the invention, pulse width modulation is used to control the switching valve, thereby reducing the power consumption of the switching valve's coil, thus lowering the operating temperature and extending its service life.

[0045] Fig. 3 shows the control of a switching valve using pulse width modulation. If a switching valve connected to one of the outputs 5a, 5b, 5c, 5d is to be switched on at time tO, it is first driven with full power for a predetermined time (pull-in time: tO to tl) to ensure the switching of the connected switching valve. Furthermore, the coil resistance can be calculated, since the coil is ohmic in this case.

[0046] NAS\14743\A_Apct exhibits resistance characteristics. The retraction time is an adjustable value that can be adapted to the connected switching valve.

[0047] The switching valve then continues to operate in PWM mode. At a constant frequency of, for example, 2,000 Hz, a desired duty cycle of a rectangular pulse is set, where the duty cycle = t / T (where t = pulse duration and T = period) is shown in the diagram in Fig. 3 as follows:

[0048] Duty cycle = (t3 - 12) / (t4 - 12)

[0049] The energy consumption is therefore proportional to the duty cycle, whereby the duty cycle is to be set so that the current through the coil of the switching valve during the off-time (t3 to t4) only drops to the point that the switching valve remains in the switched state.

[0050] Furthermore, at least one connected solenoid valve can be controlled via the second microcontroller 9 in adjustable opening and closing cycles. In a further embodiment, the switching cycles for each connected solenoid valve or lift valve are counted, and an output signal is generated when a predefined limit of switching cycles is reached. In this way, it is possible to identify in time which affected solenoid valve or lift valve needs to be replaced before it fails prematurely.

[0051] The load detection module 12 is used to detect a standard actuator 2 connected to one of the outputs 5a, 5b, 5c, or 5d. During load diagnostics, the output can be subjected to an output voltage below 1V and a minimum current of less than 300pA, thus detecting whether a load (standard actuator) is connected to the output without having to switch the load. For example, a connected solenoid valve can be identified by measuring and evaluating the coil resistance of the associated coil from the IO-Link hub.

[0052] The current measurement and diagnostic module 13 features in particular a shunt resistor which is connected to an integrated circuit specifically designed for current measurement.

[0053] NAS\14743\A_Apct is connected. The integrated circuit is preferably designed such that not only the current but also the output voltage can be measured, and it is possible to generate different error signals for voltage and current. Using the current measurement and diagnostic module 13, the switching time for activating the solenoid valve / lift valve can also be determined and evaluated.

[0054] Furthermore, the coil state of the connected solenoid valve can be determined and evaluated based on the current flowing to the solenoid valve. Additionally, the current consumption of the connected solenoid valve can be determined and evaluated.

[0055] NAS\14743\A_Apct

Claims

Patent claims:

1. IO-Link hub (1) for operating a large number of standard actuators (2) with - an IO-Link interface (3) for connection to an IO-Link master (4), - a variety of outputs (5a, 5b, 5c, 5d) for connection to the Standard actuators (2), - at least a first microcontroller (8) for communication with the IO-Link master (4) and the standard actuators (2), characterized by a second microcontroller (9) which is designed to control at least one standard actuator (2) designed as a solenoid valve or lift valve and to evaluate status data of the solenoid valve or lift valve.

2. IO-Link hub (1) according to claim 1, characterized in that the second microcontroller (9) is connected to an output stage (10) which comprises a PWM module (11) for PWM control of the at least one connected solenoid valve or lift valve.

3. IO-Link hub (1) according to claim 1 or 2, characterized in that the second microcontroller is connected to an output stage (10) which comprises a load detection module (12) for detecting a solenoid valve or lift valve connected to one of the outputs (5a, 5b, 5c, 5d).

4. IO-Link hub (1) according to one of claims 1, 2 or 3, characterized in that the second microcontroller is connected to an output stage (10) which comprises a current measurement and diagnostic module (13) for measuring the current of the solenoid or lift valves connected to the outputs (5a, 5b, 5c, 5d) and for evaluating current measurement signals. NAS\14743\A_Apct 5. IO-Link hub (1) according to claim 1, characterized in that the first microcontroller (8) and the second microcontroller (9) are arranged galvanically isolated from each other.

6. IO-Link hub (1) according to claim 1, characterized in that the second microcontroller (9) is configured to control a solenoid valve designed as a switching valve.

7. IO-Link hub (1) according to claim 1, characterized in that the IO-Link hub is designed for both Class A and Class B operation.

8. Method for operating an IO-Link hub (1) according to any one of claims 1 to 7 comprising the following method steps: Establishing a connection between the IO-Link Hub (1) and a 10-Link Master (4), - Establishing a connection between the IO-Link hub (1) and at least one standard actuator (2) designed as a solenoid valve or stroke valve, - Providing a communication interface (3) by means of a first microcontroller (8) for communication with the IO-Link master (4) and the at least one standard actuator (2), characterized by providing a second microcontroller (9) for controlling the at least one solenoid valve or lift valve and for evaluating status data of the solenoid valve or lift valve.

9. Method according to claim 8, characterized in that a switching valve is used as the solenoid valve, which is controlled via the second microcontroller (9) by means of dynamic pulse width modulation. NAS\14743\A_Apct 10. Method according to claim 8, characterized in that the at least one connected solenoid valve can be controlled in adjustable opening and closing cycles.

11. Method according to claim 8, characterized in that the switching cycles for each connected solenoid valve or lift valve are counted and an output signal is generated when a predetermined limit of switching cycles is reached.

12. Method according to claim 8, characterized in that LEDs provided on the IO-Link hub (1) are controlled for localizing the IO-Link hub (1) and / or for displaying the status of connected standard actuators (2).

13. Method according to claim 8, characterized in that the solenoid valve has a coil whose coil resistance is measured and evaluated by the IO-Link hub (1).

14. Method according to claim 8, characterized in that the switching time for activating and deactivating the solenoid valve is determined and evaluated.

15. Method according to claim 8, characterized in that a coil state of the connected solenoid valve is determined and evaluated based on the current to the solenoid valve.

16. Method according to claim 8, characterized in that the power consumption of the connected solenoid valve is determined and evaluated. NAS\14743\A_Apct

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