CONDITION MONITORING DEVICE FOR MONITORING THE CONDITION OF A MECHANICAL MACHINE COMPONENT

Abstract

The present disclosure relates to a condition monitoring device for monitoring a condition of a mechanical machine component. The condition monitoring device may include a vibration sensor configured to detect mechanical vibrations on the mechanical machine component; a controller coupled to the vibration sensor and configured to determine a condition of the mechanical machine component based at least in part on measurement data. generated by the vibration sensor; and a wired communication interface coupled to the controller and configured to communicate with an external control device, wherein, based at least in part on a request to provide information about the condition of the mechanical machine component, the controller is configured to transmit the requested information via the wired communication interface.

Claims

1. A condition monitoring device for monitoring a condition of a mechanical machine component, comprising: a vibration sensor configured to detect mechanical vibrations on the mechanical machine component; a controller coupled to the vibration sensor and configured to determine the condition of the mechanical machine component based at least in part on measurement data generated by the vibration sensor; and a wired communication interface coupled to the controller and configured to communicate with an external control device, wherein, based at least in part on a request to provide information about the condition of the mechanical machine component, the controller is configured to transmit the requested information via the wired communication interface.

2. The condition monitoring device according to claim 1, wherein the wired communication interface is configured to couple the condition monitoring device to the external control device via a point-to-point connection.

3. The condition monitoring device according to claim 1, wherein the wired communication interface is configured to supply the condition monitoring device with external direct current (DC) voltage.

4. The condition monitoring device according to claim 3, further comprising: a DC converter configured to convert the external DC voltage supplied via the wired communication interface to an internal system voltage.

5. The condition monitoring device according to claim 1, wherein the controller is configured to operate as a slave in a master/slave operation and is configured to be controlled via the wired communication interface.

6. The condition monitoring device according to clam 1, wherein the wired communication interface comprises an input output (IO)-link interface.

7. The condition monitoring device according to claim 6, further comprising: an IO-link physical layer (PHY) module configured to transmit information about the condition of the mechanical machine component to the external control device.

8. The condition monitoring device according to claim 1, further comprising: a first input configured to connect at least one external temperature sensor configured to record at least one temperature of the mechanical machine component, wherein the controller is configured to determine the condition of the mechanical machine component based at least in part on measurement data from the first input.

9. The condition monitoring device according to claim 8, wherein the first input comprises a plurality of resistance temperature detection (RTD) lines for configured to connect at least one external resistance temperature sensor.

10. The condition monitoring device according to claim 9, further comprising: an internal power source configured to drive a prespecified current through the at least one external resistance temperature sensor via the plurality of RTD lines.

11. The condition monitoring device according to claim 10, further comprising: a first analogue to digital (A/D) converter configured to detect a voltage drop at the plurality of RTD lines and relay a digital value of the voltage drop to the controller.

12. The condition monitoring device according to claim 11, wherein the controller is configured to calculate a resistance proportional to a measured temperature of the at least one external resistance temperature sensor based at least in part on the voltage drop at the plurality of RTD lines and the prespecified current driven via the plurality of RTD lines.

13. The condition monitoring device according to claim 1, further comprising: a second input configured to connect at least one external speed or position sensor configured to record at least one speed or position, respectively, of the mechanical machine component, wherein the controller is configured to determine the condition of the mechanical machine component based at least in part on measurement data from the second input.

14. The condition monitoring device according to claim 13, further comprising: at least one Synchronous Serial Interface (SSI) configured to read the measurement data of the at least one external speed or position sensor connected to the second input and transmit the measurement data from the second input to the controller.

15. The condition monitoring device according to claim 1, wherein the vibration sensor is configured as a microelectromechanical system (MEMS)-based semiconductor-based vibration sensor.

16. The condition monitoring device according to claim 1, wherein the controller is configured to determine an amplitude spectrum based at least in part on the measurement data generated by the vibration sensor.

17. The condition monitoring device according to claim 16, further comprising: a high-pass filter configured to filter the measurement data generated by the vibration sensor; a rectifier configured to rectify the high-pass filtered measurement data of the vibration sensor; and a second analogue to digital (A/D) converter configured to convert the rectified high-pass filtered measurement data of the vibration sensor to digital measurement data, wherein the controller is configured to determine the amplitude spectrum based at least in part on the digital measurement data of the vibration sensor.

18. The condition monitoring device according to claim 17, wherein the second A/D converter is integrated in the vibration sensor, and wherein the high-pass filter comprises a function in the controller.

19. The condition monitoring device according to claim 1, wherein the wired communication interface comprises an M12 threaded coupling connector configured to activate the external control device and to connect to a power supply.

20. A method for monitoring a condition of a mechanical machine component, comprising: detecting, by a vibration sensor, mechanical vibrations on the mechanical machine component; determining the condition of the mechanical machine component based at least in part on measurement data generated by the vibration sensor; and transmitting, via a wired communication interface to an external control device, information about the condition of the mechanical machine component based at least in part on a request to provide the information.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Further examples of the principles of the present disclosure will be explained with reference to the accompanying drawings.

[0052] FIG. 1 shows a schematic illustration of a condition monitoring device 100 for monitoring the condition of a mechanical machine component,

[0053] FIG. 2 shows a schematic illustration of an IO-link device 200 for condition monitoring according to a first example,

[0054] FIG. 3 shows a schematic illustration of an IO-link device 300 for condition monitoring according to a second example, and

[0055] FIG. 4 shows a schematic illustration of a method 400 for monitoring the condition of a mechanical machine component.

DETAILED DESCRIPTION

[0056] IO-link systems and IO-link devices and/or measuring devices with an IO-link interface are described in the following.

[0057] IO-link is a serial, bidirectional point-to-point connection for signal transmission and power supply under any type of network, fieldbus or rear wall bus.

[0058] An IO-link system consists of IO-link devices, usually sensors, actuators or combinations thereof, as well as a standard 3-lead sensor/actuator cable and an IO-link master. The master can be configured as a device of any design and protection type.

[0059] The IO-link master establishes the connection between the IO-link devices and the automation system. As a component of a peripheral system, the IO-link master is installed either in the control cabinet, for example, or directly in the field as a remote I/O. The IO-link master communicates via various fieldbuses or product-specific rear wall buses. An IO-link master can have several IO-Link ports (channels). An IO-link device can be connected to every port (via point-to-point communication). Therefore IO-link is a point-to-point communication.

[0060] Amongst other things, M12 connectors are defined for the connection technology in IP65/67, whereby sensors typically have a 4 pin plug and actuators have a 5 pin plug. IO-link masters generally have a 5 pin M12 socket.

[0061] According to IEC 60974-5-2, the pin assignment is specified as follows: Pin 1: 24 V; Pin 3: 0 V; Pin 4: Switching and communication line (C/Q). In addition to the IO-link communication, a power supply of the device with a maximum of 200 mA is realised via these 3 pins.

[0062] The measuring devices having a SPI and a universal asynchronous receiver-transmitter (UART) interface are described in the following. The serial peripheral interface (SPI) is a bus system for a synchronous serial data bus, with which digital circuits can be connected to each other according to the master/slave principle. A UART interface is used for sending and receiving data via a data line and is the standard for serial interfaces on personal computers (PCs), microcontrollers, as well as in the industrial sector. The data is transmitted as a serial digital data stream having a fixed frame, which consists of a start bit, five to at most nine data bits, an optional parity bit for detecting transmission errors and a stop bit.

[0063] The devices described in the following include communication interfaces that operate according to the master/slave principle. Master/slave, or host computer/satellite computer, is a hierarchical concept for the organisation and distribution of tasks between superordinate stations, in this case the master stations, and subordinate computing units, the slaves. Such concepts are used whenever a computing unit takes over control and task distribution from another.

[0064] The master/slave concept is realised in client/server architectures, fieldbuses and Bluetooth, amongst other things. In the client/server principle, the server operates as a master station, which is equipped with its own operating system, higher intelligence and greater functionality than the clients. The clients acting as slave stations are passive communication participants that are prompted to receive or send data by the master station.

[0065] MEMS sensors, in particular MEMS vibration sensors, will he described in the following. MEMS (micro-electro-mechanical systems) are tiny components that combine logic elements and micromechanical structures in a chip. They can process mechanical and electrical information. MEMS elements are used in sensors, actuators, oscillators and filters. These mechatronic chips are usually made of silicon. The structures can be smaller than a micron. As a result of the miniaturization, they can be produced cheaply and in bulk, like semiconductors. MEMS vibration sensors are designed to measure vibrations or mechanical vibrations.

[0066] FIG. 1 shows a schematic illustration of a condition monitoring device 100 for monitoring the condition of a mechanical machine component. The condition monitoring device 100 comprises a vibration sensor 110, a controller 101 and a wired communication interface 120.

[0067] The vibration sensor 110 is used to detect mechanical vibrations on the machine component. The controller 101 is coupled to the vibration sensor 110 and is configured to determine a condition of the machine component on the basis of measurement data 116 generated by the vibration sensor 110. The communication interface 120 is coupled to the controller 101 in terms of communication and is designed to communicate with an external control device. Based on a request to provide information about the condition of the machine component, the controller 101 is configured to transmit the requested information via the wired communication interface 120.

[0068] The communication interface 120 can, for example, be configured to couple the condition monitoring device 100 to the external control device via a point-to-point connection. The communication interface 120 can be configured to supply the condition monitoring device with external DC voltage.

[0069] The controller 101 can operate as a slave in a master/slave operation and can be controlled via the communication interface 120.

[0070] The communication interface 120 can comprise an IO-link interface, as described. in FIGS. 2 and 3, for example.

[0071] The condition monitoring device 100 can comprise an IO-link PHY module 121, as shown in FIGS. 2 and 3 for example, which is configured to transmit the information about the condition of the machine component to the external control device.

[0072] In an example, the condition monitoring device 100 comprises a DC converter 123, which is configured to convert the external DC voltage supplied via the communication interface 120 into an internal system voltage 124, for example according to the illustration in FIG. 2 or 3.

[0073] In one example, the condition monitoring device 100 can comprise a first input 140 for connecting at least one external temperature sensor for recording at least one temperature of the machine component, as shown in FIGS. 2 and 3 for example. The controller 101 can be configured to further determine the condition of the machine component on the basis of measurement data 146 from the first input 140, as described in FIGS. 2 and 3 for example.

[0074] The first input 140 can comprise a plurality of RTD lines for connecting at least one external resistance temperature sensor. The condition monitoring device 100 can further comprise an internal power source 142, as shown in FIGS. 2 and 3 for example, which is configured to drive a prespecified current through the at least one external resistance temperature sensor via the RTD lines. The condition monitoring device 100 can further comprise a first analogue to digital (A/D) converter 143, as shown in FIGS. 2 and 3 for example, which is configured to detect a voltage drop at the RTD lines and relay it to the controller 101 converted to a digital value. The controller 101 can be configured to calculate a resistance proportional to the measured temperature of the at least one resistance temperature sensor on the basis of the voltage drop at the RTL) lines and the prespecified current driven via the RTD lines.

[0075] The condition monitoring device 100 can further comprise a second input 130 for connecting at least one external speed and/or position sensor for recording at least one speed and/or position of the machine component, as shown in FIGS. 2 and 3 for example. The controller 101 can be configured to further determine the condition of the machine component on the basis of measurement data 136 from the second input 130. The condition monitoring device 100 can further comprise at least one Synchronous Serial Interface (SSI) 132, as shown in FIGS. 2 and 3 for example, which is configured to read the measurement data 136 of the at least one external speed and/or position sensor connected to the second input 130 and transmit said data to the controller 101.

[0076] The vibration sensor 110 can, for example, be configured as a MEMS-based semiconductor-based vibration sensor.

[0077] The controller 101 can be configured to determine an amplitude spectrum on the basis of the measurement data 116 generated by the vibration sensor 110, for example using a frequency transformation such as a Discrete Fourier Transform (DFT) or a Fast Fourier Transform (FFT).

[0078] In one example, the condition monitoring device 100 can comprise a high-pass filter 111 for filtering the measurement data 116 generated by the vibration sensor 110, as well as a rectifier 112 for rectifying the high-pass filtered measurement data of the vibration sensor 110 and a second analogue to digital (A/D) converter 113 for converting the rectified high-pass-filtered measurement data of the vibration sensor 110 to digital measurement data, as shown in FIGS. 2 and 3 for example. The controller 101 can be configured to determine the amplitude spectrum on the basis of the digital measurement data of the vibration sensor 110.

[0079] In one example, the second A/D converter 113 can be integrated in the vibration sensor 110, as shown in FIG. 3 for example. The high-pass filter 111 can be realised as a function in the controller 101, for example as a DSP (digital signal processing) function.

[0080] In one example, the communication interface 120 can comprise an M12 threaded coupling connector 122 for activating the external control device and for the power supply, as shown in FIGS. 2 and 3 for example.

[0081] FIG. 2 shows a schematic illustration of an IO-link device 200 for condition monitoring according to a first example.

[0082] The IO-link device 200 is a special example of the condition monitoring device 100 described above with respect to FIG. 1. The IO-link device 200 comprises a vibration sensor 110, a controller 101 and an IO-link interface 120.

[0083] The vibration sensor 110 is used to detect mechanical vibrations on the machine component. The controller 101 is coupled to the vibration sensor 110 and is configured to determine a condition of the machine component on the basis of measurement data 116 generated by the vibration sensor 110. The IO-link interface 120 is coupled to the controller 101 in terms of communication and is designed to communicate with an external control device, for example an IO-link master. Based on a request from the external control device to provide information about the condition of the machine component, the controller 101 is configured to transmit the requested information to the external control device via the wired communication interface 120.

[0084] The IO-link device 200 comprises an IO-link PHY module, which realises communication to the IO-link master at a physical level and transmits data from the IO-link device 200, which is functioning as a slave, to the control device, which is functioning as a master. The communication interface comprises an M12 threaded coupling connector 122, to which a cable can be screwed to connect the IO-link device 200 to the control device. The supply voltage of the IO-link device 200, which can be converted into the system voltage of the IO-link device 200, e.g., 3.3 V, in a DC/DC component, is transmitted via the IO-link 120.

[0085] The vibration sensor 110 is configured as a MEMS vibration sensor and is coupled to a SPI interface of the microcontroller 101 via a high-pass filter 111, a rectifier 112 and an analogue to digital converter 113.

[0086] A first input 140 serves to connect one or more temperature sensors, e.g., resistance thermometers, via an M8 threaded coupling connector 141. A power source 142 supplies a predefined current to drive the temperature sensors with electricity. The resulting temperature-dependent voltage change is recorded by a second analogue to digital converter 143 and converted to a digital measured value, which is transmitted to a SPI interface 144 of the microcontroller 101.

[0087] A second input 130 serves to connect one or more speed and/or position sensors via an M8 threaded coupling connector 131. The measured values 136 of these sensors are read by an SSI interface 132 and made available to the microprocessor.

[0088] In the case of the IO-link device 200 shown in FIG. 2, the above-mentioned functions such as vibration, temperature and speed measurement are combined in a device. The evaluation of the measurement signals is also carried out in the device. The sensor/actuator bus standard IO-link is selected as the bus system. A 24 V power supply, which serves as a supply for the device 200, is also provided via the IO-link cable 120. The device 200 is connected with only one cable and can therefore be screwed directly to the machine in a decentralised manner. In addition to the condition of the bearing, measured values such as spectrum and amplitude of the vibration, as well as bearing temperature and speed, can be transmitted via the bus 120 as well. Using the user parameterised data relating to the bearing, such as speed and maximum bearing temperature, the condition of the bearing and the remaining service life in the device 200 are calculated by the microcontroller 101. In addition to using only one device, the user is also spared the cost of an expensive, external piezo vibration sensor.

[0089] The device 200 is configured as an IO-link slave (device) and is connected to the IO-link master via the standardised M12 threaded coupling connector 122. A 24 V operating voltage, with which the device 200 is supplied, is also provided in the IO-link line 120 in addition to the bus signals. Using an integrated DC/DC converter 123, the 3.3 V system voltage 124 is generated from the 24 V in the device 200. The data from the slave 200 is transmitted to the master via the IO-link PHY 121.

[0090] The device 200 has an integrated MEMS-based (semiconductor-based) vibration sensor 110. For an optimum evaluation of the spectrum and the amplitude of the vibration, the analogue sensor signals 116 are first discretely high-pass filtered 111, rectified 112 and collected by an analogue to digital converter 113. The transmission of the measured values from the application delivery controller (ADC) 113 to the microcontroller 101 takes place via an SPI interface 114.

[0091] The ADC 113 can alternatively be integrated in the vibration sensor 110, as shown in the second example of the IO-link device 300 in FIG. 3. The data is transmitted to the microcontroller 101 via an SPI interface 114. The high-pass filter 111 is realised in the microcontroller 101 with a DSP function, as shown in FIG. 3. An amplitude spectrum is calculated from the discrete time measured values in the microcontroller 101 using an FFT (fast Fourier transform).

[0092] Temperature sensors can be connected to the two or more RTD temperature inputs 140 using M8 threaded coupling connectors 141, e.g., PT100. The electrical resistance of the sensor is proportional to the temperature. Internal power sources 142 drive a defined current through the temperature sensor. The voltage drop at the sensor measured with an analogue to digital converter 143 is transmitted to the microcontroller 101 via an SPI interface 144. The temperature-proportional resistance is calculated in the microcontroller 101 using the voltage drop and the driven current.

[0093] Speed or position sensors can be connected to the one or more SSI interfaces 132. The data is transmitted from the sensor to the microcontroller 101 via the hardware driver and evaluated by the microcontroller.

[0094] The microcontroller 101 records the individual sensor signals and from them calculates the bearing temperature, the speed, the amplitude and spectrum of the vibration, and the condition of the bearing. The microcontroller 101 is connected to the IO-link PHY 121 via a UART interface, includes the IO-link stack and establishes the communication to the master for data transmission.

[0095] FIG. 3 shows a schematic illustration of an IO-link device 300 for condition monitoring according to a second example.

[0096] The IO-link device 300 is a special example of the condition monitoring device 100 described above with respect to FIG. 1. The IO-link device 300 corresponds to the IO-link 200 described in FIG. 2, wherein the analogue to digital converter 113 is integrated in the MEMS vibration sensor 110 and the high-pass filter 111 is realised as a function, e.g., a DSP function, in the microcontroller 101.

[0097] FIGS. 2 and 3 thus respectively show an IO-link device 200, 300 having an M12 threaded coupling connector 122 for the bus interface and the power supply; an integrated DC/DC converter 123 for generating the internal system voltage; an integrated microcontroller 101 for signal processing and signal evaluation and bus communication; an integrated MEMS-based vibration sensor 110 for vibration measurement (amplitude and spectrum); RTD inputs 140 for connecting external temperature sensors with M8 threaded coupling connectors 141; and SSI inputs 130 for connecting external speed and position sensors with M8 threaded coupling connectors 131.

[0098] FIG. 4 shows a schematic illustration of a method 400 for monitoring the condition of a mechanical machine component.

[0099] The method 400 comprises the following steps: Detection 401 of mechanical vibrations on a machine component by a vibration sensor; determining 402 a condition of the machine component on the basis of measurement data generated by the vibration sensor; and transmitting 403 information about the condition of the machine component via a wired communication interface based on a request to provide the information.

[0100] The method 400 can, for example, be realised in a condition monitoring device 100 or an IO-link device 200, 300 as described above with respect to FIGS. 1 to 3.

LIST OF REFERENCE NUMBERS

[0101] 100 Condition monitoring device [0102] 101 Controller, microcontroller [0103] 110 Vibration sensor, MEMS vibration sensor [0104] 111 High-pass filter [0105] 112 Rectifier [0106] 113 Analogue to digital converter [0107] 114 SPI interface [0108] 116 Measurement data of the vibration sensor [0109] 120 Communication interface wired, IO-link bus to master [0110] 121 IO-link PHY [0111] 122 M12 threaded coupling connector [0112] 130 Second input [0113] 131 M8 threaded coupling connector [0114] 132 SSI interface [0115] 136 Measurement data of the second input [0116] 140 First input [0117] 141 M8 threaded coupling connector [0118] 142 Power source [0119] 143 Analogue to digital converter [0120] 144 SPI interface [0121] 146 Measurement data of the first input [0122] 200 IO-link device according to the first example [0123] 300 IO-link device according to the second example [0124] 400 Method for monitoring the condition of a mechanical machine component [0125] 401 First step: Recording [0126] 402 Second step: Determining [0127] 403 Third step: Transmitting