DE102024112832A1 - system with drive and smartphone - Google Patents

Abstract

System, comprising - a drive which has a gear driven by an electric motor, - a support means with a permanent magnet and - a smartphone, wherein the smartphone has - a vibration sensor, - a data collection device, - a means for signal transformation and - an evaluation unit, wherein the smartphone is designed to - feed the values recorded by the vibration sensor to the data collection device, - store a temporal progression of the values in the data collection device as a value progression, - transform the value progression using the means for signal transformation, - evaluate the transformed value progression with the evaluation unit and compare it with transformed value progressions previously stored in the smartphone and, if the deviation of the transformed value progression from the stored transformed value progressions is unacceptably high, display and/or send a warning.

Description

The invention relates to a system with drive and smartphone.

It is generally known that a smartphone is a mobile and/or portable communications device whose largest dimension is less than 17 cm and whose mass is less than 200 grams, whereby the smartphone can be operated as a participant in a wireless local network, in particular for exchanging data with another participant in the local network.

From the KR 2022 0 077 004 A The closest state of the art is a smartphone sensor-based condition monitoring measurement method.

From the US 6 297 742 B1 Machine monitoring is known.

From the US 2021 / 0 247 269 A1 A fault analysis procedure is known.

From the AT 523 109 B1 A method for calibrating a control device of an electric motor is known.

From the DE 10 2010 051 864 B4 A method for operating a drive is known.

The invention is therefore based on the object of developing a simple and cost-effective analysis of a drive.

According to the invention, the object is achieved in the system according to the features specified in claim 1.

• - einen Antrieb, insbesonderer einen von einem Umrichter gespeisten Getriebemotor, welcher ein von einem Elektromotor angetriebenes Getriebe aufweist,
• - ein Auflagemittel mit Dauermagnet und
• - ein Smarthone

aufweist, wobei das Smartphone

• - einen Vibrationssensor, insbesondere Körperschallsensor,
• - eine Datensammelvorrichtung,
• - ein Mittel zur Signaltransformation und
• - eine Auswerteeinheit

aufweist,
wobei das Smartphone geeignet ausgeführt ist,

• - die vom Vibrationssensor erfassten Werte der Datensammelvorrichtung zuzuführen,
• - einen zeitlichen Verlauf der Werte in der Datensammelvorrichtung als Werteverlauf abzuspeichern,
• - den Werteverlauf mit dem Mittel zur Signaltransformation zu transformieren,
• - mit der Auswerteeinheit den transformierten Werteverlauf auszuwerten und dabei mit zuvor im Smartphone gespeicherten transformierten Werteverläufen zu vergleichen und bei unzulässig hoher Abweichung des transformierten Werteverlaufs zu den gespeicherten transformierten Werteverläufen eine Warnung anzuzeigen und/oder abzuschicken und/oder abzusenden.

Important features of the invention in the system are that the system

• - a drive, in particular a geared motor fed by a converter, which has a gear driven by an electric motor,
• - a support with permanent magnet and
• - a smartphone

, whereby the smartphone

• - a vibration sensor, in particular a structure-borne sound sensor,
• - a data collection device,
• - a means of signal transformation and
• - an evaluation unit

has,
whereby the smartphone is designed appropriately,

• - to feed the values recorded by the vibration sensor to the data collection device,
• - to store a temporal progression of the values in the data collection device as a value progression,
• - to transform the value curve using the signal transformation tool,
• - to evaluate the transformed value curve with the evaluation unit and to compare it with the transformed value curves previously stored in the smartphone and to display and/or send a warning if the transformed value curve deviates from the stored transformed value curves by an unacceptably high amount.

The advantage here is that the drive can be analyzed using a smartphone. The smartphone has a vibration sensor and is therefore able to detect the structure-borne noise emitted by a drive. This makes it possible to detect structure-borne noise in a simple and cost-effective manner. This also includes vibrations caused by imbalance.

By comparing it with value curves recorded in a good state, a different behavior can be recognized. A neural network in the evaluation unit is particularly well suited for this purpose, as it records the value curves corresponding to the good state in a learning phase and then assesses the currently recorded transformed value curve.

In an advantageous embodiment, the evaluation unit for comparison has a neural network to which the stored transformed value curves were fed, particularly in a learning phase. The advantage here is that a comparison can be carried out quickly and easily.

In an advantageous embodiment, the signal transformation is a Laplace transformation or a Fourier transformation. The advantage here is that the effects resulting from periodic excitations are clearly recognizable, especially in a spectrum. In particular, the impermissibly high amplitude at a first frequency can be recognized quickly, easily and clearly in the spectrum.

In an advantageous embodiment, the drive has a ferromagnetic part, in particular the bearing flange of the gear,
whereby the support having the permanent magnet magnetically attached to the ferromagnetic part,
wherein the support means has a flat surface on its side facing the smartphone, on which a smartphone is placed, in particular wherein the holding means prevents the smartphone from slipping parallel to the plane of the flat surface,
in particular, the holding means is designed as an elastically deformable band, in particular which wraps around the smartphone and the drive, or the holding means comprises a material adhering to the housing of the transmission, in particular plastic, in particular plasticine. The advantage here is that the support means provides a flat surface and thus enables efficient coupling of the smartphone to the drive. By means of the magnetically attractive force, the smartphone is pressed onto the support means without play and is thus coupled sufficiently well for structure-borne sound.

In an advantageous embodiment, the support means is attached to the drive by means of a screw which is screwed into a threaded hole in the drive, in particular the ferromagnetic part, and is designed as a holder for the smartphone, in particular wherein the holder is pressed onto the ferromagnetic part by the screw. The advantage here is that a simple, cost-effective and stable attachment enables a sufficiently good coupling.

In an advantageous embodiment, the support means is attached to the drive by means of a threaded bolt that is integrally connected to a holder and is screwed into a threaded hole in the drive, in particular the ferromagnetic part, and is designed as a holder for the smartphone. The advantage here is that a simple, cost-effective, secure coupling and a stable attachment are possible.

In an advantageous embodiment, the converter has a higher-level control which is set up in such a way that the higher-level control regulates the amplitude of a first frequency of the vibration detected by the vibration sensor to zero by setting the phase and amplitude of a torque ripple which are transmitted to a control device for controlling the torque of the electric motor of the drive, the torque ripple being added to a torque setpoint of the control device. The advantage here is that after an impermissibly high amplitude is determined at the first frequency, active damping can be introduced at this frequency. This is because a sinusoidal torque ripple is added to the setpoint of the torque controller of the converter, which has the first frequency and whose phase and amplitude are set by a control device in such a way that the amplitude of the first frequency of the vibration is minimized. As soon as this minimum is found, the torque ripple found in this way is stored as a function of the angular position of the rotor shaft of the electric motor and is permanently added to the torque setpoint even in normal operation. This reduces the amplitude of the first frequency of vibration.

In an advantageous embodiment, the electric motor has an angle sensor for determining the angular position, in particular the absolute angular position, of the rotor of the electric motor and the drive is designed in such a way that the torque ripple determined as a function of the angular position, which has the amplitude and phase at which the amplitude of the first frequency of the vibration does not exceed a permissible level, is permanently added to the torque target value in normal operation, in particular when the smartphone is removed from the support means. The advantage here is that the amplitude and phase values found by means of the control to minimize the amplitude at the first frequency define a torque ripple that can be permanently added to the torque target value depending on the angular position of the rotor shaft.

• - in einem ersten Verfahrensschritt die vom Sensor erfassten Werte als Werteverlauf abgespeichert werden,
• - in einem zeitlich dem ersten nachfolgenden zweiten Verfahrensschritt der Werteverlauf transformiert wird,
• - in einem zeitlich dem zweiten nachfolgenden dritten Verfahrensschritt der Werteverlauf von einem neuronalen Netz auf Überschreiten eines zulässigen Maßes an Abweichung geprüft wird, insbesondere wobei dem neuronalen Netz in einer vor dem ersten Verfahrensschritt ausgeführten Lernphase zulässige transformierte Werteverläufe zugeführt wurden.

Important features of the procedure for operating a system are that

• - in a first process step, the values recorded by the sensor are stored as a value history,
• - in a second process step following the first, the value progression is transformed,
• - in a third method step following the second method step, the value curve is checked by a neural network for exceeding a permissible level of deviation, in particular wherein permissible transformed value curves were fed to the neural network in a learning phase carried out before the first method step.

The advantage is that the procedure can be carried out using a smartphone and is therefore cost-effective and simple.

In an advantageous embodiment, in a fourth method step following the third step, the amplitude of a first frequency of the vibration detected by the vibration sensor is regulated to zero by the higher-level control setting the phase and amplitude of a torque ripple, which is sent to a control device for Control of the torque of the electric motor of the drive, whereby the torque ripple is added to a torque setpoint of the control device. The advantage here is that the impermissibly high amplitude of the first frequency can be reduced by finding the optimal torque ripple from the control device and then this torque ripple can be added to the torque setpoint as an angle-dependent function permanently, i.e. even after the smartphone has been removed.

In an advantageous embodiment, the angular position, in particular the absolute angular position, of the rotor of the electric motor is determined and the phase and the amplitude at which the smallest amplitude of the first frequency is reached are used to determine a torque ripple which has the first frequency, in particular is sinusoidal, and is determined as a function of the angular position and which is added to the torque setpoint, in particular taking into account the angle dependency,
in particular, the amplitude of the first frequency of the vibration does not exceed a permissible level, in particular in normal operation, i.e. in particular when the smartphone is removed from the support. The advantage here is that the optimal torque ripple is determined as a function of the angular position of the rotor shaft and can therefore be taken into account in continuous operation. The electric motor is preferably a synchronous motor, in particular because the torque ripple can be specified with high precision as a function of the angular position of its rotor shaft.

Further advantages arise from the subclaims. The invention is not limited to the combination of features in the claims. The person skilled in the art will recognize further useful combination options of claims and/or individual claim features and/or features of the description and/or the figures, in particular from the task and/or the task arising from comparison with the prior art.

• In der 1 ist ein erfindungsgemäßes System, aufweisend einen Antrieb, dargestellt.
• In der 2 ist ein zweites System mit einem als Elektromotor ausgeführten Antrieb dargestellt.
• In der 3 ist für ein drittes System eine Halterung 30 mit stoffschlüssig verbundenem Gewindebolzen 31 dargestellt.

The invention will now be explained in more detail using schematic illustrations:

• In the 1 a system according to the invention, comprising a drive, is shown.
• In the 2 A second system with a drive designed as an electric motor is shown.
• In the 3 For a third system, a bracket 30 with a materially connected threaded bolt 31 is shown.

As in 1 As shown, the system has a drive, in particular a geared motor, wherein a support means 2 is attached to a ferromagnetic part of the drive, for example a bearing flange, which support means comprises a permanent magnet and is thus magnetically held on the ferromagnetic part of the drive.

The support means 2 has a flat surface on its side facing away from the drive, on which a smartphone 3 is placed.

A holding means 4 prevents the smartphone from slipping parallel to the plane of the flat surface, in particular from slipping sideways of the smartphone relative to the support means 2.

The holding means 4 can be designed as an elastically deformable band which wraps around the smartphone 3 and the drive, or the holding means 4 comprises a material adhering to the housing of the transmission, in particular plastic, in particular plasticine.

The smartphone 3 has a sensor for detecting vibration, in particular structure-borne sound. The smartphone 3 also contains a data collection device in which the values detected by the sensor are stored.

Thus, after recording the temporal progression of the vibration values, in particular the structure-borne sound, an evaluation of the recorded data can be carried out.

For this purpose, the smartphone 3 has a means for signal transformation, in particular a means for Fourier transformation.

Preferably, the recorded signal curve is transformed, in particular Fourier transformed, in particular by applying an FFT, in particular Fast Fourier Transformation.

The value curve transformed in this way is fed to an evaluation unit, which compares the transformed value curve with previously stored transformed value curves and issues a warning message on smartphone 3 if there is an unacceptably high deviation. In a further development, the evaluation unit has a neural network to which permissible value curves are fed in a learning phase, so that the evaluation unit can recognize unacceptably strongly deviating value curves when operation begins after the learning phase. For example, an imbalance can be recognized on one of the rotatably mounted shafts of the gear motor.

Preferably, the smartphone 3 has a ferromagnetic part so that the smartphone 3 is magnetically held by the permanent magnet.

In a further embodiment according to the invention, the smartphone 3 is placed in a holder 30, which is pressed against a flat surface area, in particular by the screw head of the screw, by means of a screw that is screwed into a threaded hole in the ferromagnetic part, in particular the bearing plate. The screw head has a permanent magnet, in particular so that the smartphone 3 rests as directly as possible on the screw head. The holder prevents the smartphone 3 from slipping sideways. Alternatively, as in 3 shown, instead of the screw, a threaded bolt 31 is designed as a composite part with the holder, in particular materially connected to the holder. The threaded bolt is screwed into the threaded hole in the ferromagnetic part, in particular the bearing plate. In this way, a particularly good coupling can be achieved. In a further development, a permanent magnet can also be arranged in the holder, so that the smartphone 3 is additionally magnetically attracted if it has a ferromagnetic part or a permanent magnet.

The evaluation unit, the means for signal transformation and the data collection device are arranged within the signal electronics of the smartphone 3 and are preferably implemented in one component, in particular IC.

In further embodiments according to the invention, a Laplace transformation is carried out instead of the Fourier transformation.

In further embodiments according to the invention, the electric motor has an angle sensor which detects the absolute angular position of the rotor shaft of the electric motor and feeds it to the signal electronics of a converter which feeds the electric motor. The signal electronics have a control device which is given a torque setpoint and also the motor current detected at the electric motor.

The converter has a rectifier which provides a unipolar intermediate circuit voltage to the inverter of the converter, whereby the electric motor is supplied from the AC voltage side connection of the inverter. The intermediate circuit voltage is also detected by a sensor and fed to the control device.

An actual value, in particular a model value, of the torque of the electric motor is determined from the recorded variables, in particular motor current and intermediate circuit voltage. The control device determines a motor voltage as a control variable, whereby the motor voltage is provided by the inverter supplied from the intermediate circuit voltage by operating its power semiconductor switches in a pulse width modulated manner.

The actual value of the torque is regulated by the control device to the torque setpoint by setting the pulse width modulation ratio for the power semiconductor switches.

From the value curve determined by the smartphone 3, at least a first frequency of the spectrum with an unacceptably high amplitude can be identified, especially in the case of a problem. The cause of this is, for example, bearing damage or wear on a tooth in the gearing of a gear part of the transmission. However, if the excessive amplitude is caused by a geometric deviation in the tooth shape or the tooth spacing, there is an increased amplitude, but no direct damage.

According to the invention, a sinusoidal torque ripple is added to the specified torque setpoint by appropriately specifying the temporal progression of the pulse width modulation ratio, so that the controller device regulates the actual value of the torque to this rippled torque setpoint. The first frequency is specified as the frequency of the torque ripple. The amplitude and phase of the torque ripple are set by a higher-level control system in such a way that the impermissibly high amplitude is regulated to zero or at least pushed into the permissible range. In this way, a reduction in structure-borne noise emissions can be achieved.

The torque ripple mentioned above therefore functions as a portion of the torque setpoint that varies periodically over time. The total torque setpoint is therefore formed as the sum of the torque setpoint and the torque ripple, with the torque ripple changing more quickly over time relative to the torque setpoint. In particular, the torque setpoint is constant over time.

The smartphone 3 is connected wirelessly, in particular by means of a radio wave transmission and/or communication connection Bluetooth, WLAN or NFC to the signal electronics of the converter, so that the amplitude of the first frequency can be transmitted to the signal electronics after being determined by the smartphone 3. The higher-level control is either in the smartphone 3 or in the signal electronics of the converter.

The torque ripple determined in this way can then be determined as a function of the angular position of the rotor shaft and can thus be permanently applied later in the normal operation of the drive to reduce emissions.

The first frequency may differ from the speed of the electric motor if the high amplitude is caused by a geared part whose speed is reduced according to a gear ratio of the gearbox. Nevertheless, the speed of the geared part is used for the torque ripple.

list of reference symbols

1

drive, especially gear motor

2

support with permanent magnet

3

smartphone

4

holding device

30

bracket

31

threaded bolt

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• KR 2022 0 077 004 A [0003]
• US 6 297 742 B1 [0004]
• US 2021 / 0 247 269 A1 [0005]
• AT 523 109 B1 [0006]
• DE 10 2010 051 864 B4 [0007]

Claims (10)

System, comprising - a drive, in particular a geared motor fed by a converter, which has a gear driven by an electric motor, - a support means with a permanent magnet and - a smartphone characterized in that the smartphone has - a vibration sensor, in particular a structure-borne sound sensor, - a data collection device, - a means for signal transformation and - an evaluation unit, wherein the smartphone is designed to - feed the values recorded by the vibration sensor to the data collection device, - store a temporal progression of the values in the data collection device as a value progression, - transform the value progression with the means for signal transformation, - evaluate the transformed value progression with the evaluation unit and compare it with transformed value progressions previously stored in the smartphone and, if the transformed value progression deviates from the stored transformed value progressions to an unacceptably high degree, display and/or send a warning. system according to claim 1 , characterized in that the evaluation unit for comparison has a neural network to which the stored transformed value curves were fed, in particular in a learning phase. System according to one of the preceding claims, characterized in that the signal transformation is a Laplace transformation or a Fourier transformation. System according to one of the preceding claims, characterized in that the drive has a ferromagnetic part, in particular a bearing flange of the gear, wherein the support means having the permanent magnet is magnetically attached to the ferromagnetic part, wherein the support means has a flat surface on its side facing the smartphone, on which a smartphone is placed, in particular wherein the holding means prevents the smartphone from slipping parallel to the plane of the flat surface, in particular wherein the holding means is designed as an elastically deformable band, in particular which wraps around the smartphone and the drive, or wherein the holding means has a material adhering to the housing of the gear, in particular plastic, in particular plasticine. System according to one of the preceding claims, characterized in that the support means is fastened to the drive by means of a screw which is screwed into a threaded bore of the drive, in particular the ferromagnetic part, and is designed as a holder for the smartphone, in particular wherein the holder is pressed onto the ferromagnetic part by the screw, or that the support means is fastened to the drive by means of a metallic threaded bolt which is integrally connected to a holder and which is screwed into a threaded bore of the drive, in particular the ferromagnetic part, and is designed as a holder for the smartphone, in particular wherein the permanent magnet is arranged in the holder, in particular is arranged encapsulated with plastic. System according to one of the preceding claims, characterized in that the converter has a higher-level control which is suitably set up in such a way that the higher-level control regulates the amplitude of a first frequency of the vibration detected by the vibration sensor to zero, in that the higher-level control sets, in particular as manipulated variables, the phase and the amplitude of a torque ripple, in particular a portion of the torque setpoint that runs periodically over time, wherein the torque ripple is added to a torque setpoint to form the torque setpoint, which is transmitted to a control device for controlling the torque of the electric motor of the drive, wherein the control device regulates the actual value of the torque of the electric motor of the drive to the torque setpoint, in particular by setting the motor voltage and/or the motor current of the electric motor. System according to one of the preceding claims, characterized in that the electric motor has an angle sensor for determining the angular position, in particular the absolute angular position, of the rotor of the electric motor and the drive is designed in such a way that the torque ripple determined as a function of the angular position, which has the amplitude and phase at which the amplitude of the first frequency of the vibration does not exceed a permissible level is permanently added to the torque setpoint during normal operation, especially when the smartphone is removed from the support. Method for operating a system, in particular according to one of the preceding claims, characterized in that - in a first method step, the values detected by the sensor are stored as a value curve, - in a second method step following the first in time, the value curve is transformed, - in a third method step following the second in time, the value curve is checked by a neural network for exceeding a permissible degree of deviation, in particular wherein permissible transformed value curves were fed to the neural network in a learning phase carried out before the first method step. Method according to one of the preceding claims, characterized in that in a fourth method step following the third, the amplitude of a first frequency of the vibration detected by the vibration sensor is regulated to zero by the higher-level control setting the phase and amplitude of a torque ripple, in particular a temporally periodic portion of the torque setpoint, which are transmitted to a control device for controlling the torque of the electric motor of the drive, wherein the torque ripple is added to a torque setpoint of the control device, and/or in a fourth method step following the third, the amplitude of a first frequency of the vibration detected by the vibration sensor is regulated to zero by the higher-level control setting the phase and amplitude of a torque ripple, in particular as manipulated variables, wherein the torque ripple is added to a torque setpoint to form the torque setpoint, which is transmitted to a control device for controlling the torque of the electric motor of the drive, wherein the control device sets the actual value of the torque of the electric motor of the drive to the torque setpoint in particular by adjusting the motor voltage and/or the motor current of the electric motor. System according to one of the preceding claims, characterized in that the angular position, in particular absolute angular position, of the rotor of the electric motor is determined and the phase and the amplitude at which the smallest amplitude of the first frequency is reached are used to determine a torque ripple which has the first frequency, in particular is sinusoidal, and is determined as a function of the angular position and which is added to the torque target value, in particular taking the angular dependence into account, in particular wherein the amplitude of the first frequency of the vibration does not exceed a permissible level, in particular in normal operation, i.e. in particular when the smartphone is removed from the support means.

Images