DE19626669C1 - Brake-lining wear monitoring method for brake lining of brake motor - Google Patents

Brake-lining wear monitoring method for brake lining of brake motor

Info

Publication number
DE19626669C1
DE19626669C1 DE19626669A DE19626669A DE19626669C1 DE 19626669 C1 DE19626669 C1 DE 19626669C1 DE 19626669 A DE19626669 A DE 19626669A DE 19626669 A DE19626669 A DE 19626669A DE 19626669 C1 DE19626669 C1 DE 19626669C1
Authority
DE
Germany
Prior art keywords
characterized
brake
structure
accelerometer
device according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
DE19626669A
Other languages
German (de)
Inventor
Helmut Dr Nestler
Karl-Heinz Dr Meiser
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SEW Eurodrive GmbH and Co KG
Original Assignee
SEW Eurodrive GmbH and Co KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by SEW Eurodrive GmbH and Co KG filed Critical SEW Eurodrive GmbH and Co KG
Priority to DE19626669A priority Critical patent/DE19626669C1/en
Application granted granted Critical
Publication of DE19626669C1 publication Critical patent/DE19626669C1/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K7/00Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/10Structural association with clutches, brakes, gears, pulleys or mechanical starters
    • H02K7/102Structural association with clutches, brakes, gears, pulleys or mechanical starters with friction brakes
    • H02K7/1021Magnetically influenced friction brakes
    • H02K7/1023Magnetically influenced friction brakes using electromagnets
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D66/00Arrangements for monitoring working conditions, e.g. wear, temperature
    • F16D66/02Apparatus for indicating wear
    • F16D66/021Apparatus for indicating wear using electrical detection or indication means
    • F16D66/026Apparatus for indicating wear using electrical detection or indication means indicating different degrees of lining wear
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K11/00Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
    • H02K11/20Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection for measuring, monitoring, testing, protecting or switching
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K11/00Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
    • H02K11/30Structural association with control circuits or drive circuits
    • H02K11/35Devices for recording or transmitting machine parameters, e.g. memory chips or radio transmitters for diagnosis
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D66/00Arrangements for monitoring working conditions, e.g. wear, temperature
    • F16D2066/006Arrangements for monitoring working conditions, e.g. wear, temperature without direct measurement of the quantity monitored, e.g. wear or temperature calculated form force and duration of braking

Abstract

The method measures the sound using sensor (3) and draws conclusions from the changes in the sound measured using also acceleration sensor (3) mounted on brake motor (1). A high sampling frequency is used on the signal detected by the acceleration transducer. The spectrum of the sound in solid or of the acceleration is obtained by fast Fourier transform (FFT) of the time variation of the sound in solid or acceleration.

Description

The invention relates to a method and a device to monitor the wear of a brake pad Brake motors.

A generic method and a generic one Devices are known from DE 37 39 836 C2. The Brake wear is monitored here by a measurement looped into the lead of the brake magnet circuit, with the brake pad pressed onto the in Dependence of the working air gap and thus in dependency current of the thickness of the brake pad appeals to strength.

It is also known to monitor the brake pad wear with brake motors, i.e. electromagnets with turned on builders electromagnetic release brake, by means of di air gap measurement using sensors, Proximity switches, microswitches or distance sensors in the brake can be installed after exceeding the maximum permitted brake air gap, for example trigger a monitoring circuit. The installation  such sensors in the brake is extremely difficult because the brake is structurally modifiable must be decorated and on the other hand a manual adjustment of the built-in sensors is necessary for the smoldering lenwert for the "good" / "bad" detection correctly recorded can be. The fact that the sensor in each Brake is not a sensor for any many motors are used. Accordingly arise high manufacturing costs for brake motors with such Brake pad wear monitoring sensors. The white Due to the "good" / "bad" recognition, teren is not continuous monitoring of brake pad wear possible. Also, there is no reliable detection of the threshold value over the service life possible because the Senso are temperature sensitive.

A brake motor as such is in Meyers Lexikon Technology and the exact natural sciences, Volume 1, A-E, Mannheim u. a. Bibliographisches Institut 1969, page 411.

From DE 38 28 932 A1 it is known to use electric motors Monitor with the help of a structure-borne noise sensor.

DE 41 16 345 A1 relates to a method for damage early detection of a body that is continuously in operation sound-emitting rotating component of a machine. The structure-borne noise parameters are measured using a single Sound sensor measured and through filters in one high frequency and a low frequency range of Frequency spectrum separated. There are body shells power spectra and a coherence function calculated. This can damage a component Machine, that is to say, can also be recognized by wearing parts The use of structure-borne noise measurement to determine the  Wear behavior of a wearing part is not specifically addressed.

From TR Technische Rundschau Issue 5, 1993, pp. 48-51 Known tool wear with the help of the Machining process on the tool generated ultrasound monitor signals (processing noise).

From "VDI guidelines", VDI 2563 draft, Aug. 1988, Pages 1, 11 and 12, it is known that when braking Squeaking, squeaking, brake rubbing and Scraping and rubbing noises can occur. Cause is a sliding friction process between the brake pad and brake disc or brake drum.

From "VDI Reports" No. 368, 1980, pages 59-65, it is known that each braking system from individual parts, e.g. B. brake pads gene exists, which are capable of vibrating by themselves.

The invention has for its object a method and a device of the type mentioned above to develop that while avoiding the aforementioned Disadvantages of continuous monitoring of the brake lag wear with simple assembly and low fro position costs is possible.

According to the invention, the stated task is carried out at a Process of the type mentioned solved in that the structure-borne noise of the brake motor when the brake is applied measured and from the change in structure-borne noise the wear of the brake pad is closed. A Device according to the invention is characterized by at least a structure-borne noise sensor from the one the body sound of the brake motor corresponding sensor signal  outputs a signal processing and evaluation device. Monitoring of the brake lining wear is therefore carried out no longer through direct air gap monitoring, but instead by measuring the structure-borne noise, which is caused by the opening the armature disk hits the brake pad when it drops the brake is created in the brake motor. The invention makes thereby from the surprisingly found out nis use that the structure-borne noise with increasing Air gap enlargement, i.e. increasing wear of the Brake pads, continuously changed. Since the body  perschall spreads over the entire brake motor, it is no longer necessary to directly in the structure-borne noise sensor to arrange the or on the brake, so that a simple Installation or attachment in any existing system without welding is possible and so many systems with can be controlled by a sensor. By the Si Signal processing and evaluation device can be by means of the device according to the invention a reliable Processing and evaluation of the measured sensor signals take place so that the changes in structure-borne noise corresponding changes in each case Air gap size can be assigned.

The structure-borne noise is preferably by means of an Brake motor attached accelerometer measured sen. This means that one corresponds to the structure-borne noise de size, namely the time course of the acceleration tion during the application of the brakes, i.e. the strength ßes stress on the component or brake motor, measured will. With such an accelerometer can occur when the brakes are applied and the anchor hits resulting damped vibration optimally recorded will. The structure-borne noise or the acceleration measured over a given time interval, where the sampling frequency is high in order to to enable an accurate recording of the measurement data.

In training it is provided that from the temporal Structure-borne noise or acceleration due to rapid Fourier transform (FFT) the structure-borne sound frequency spectrum or the acceleration spectrum is determined. As a result, the measured acceleration or Structure-borne noise amplitudes each different Vibration frequencies when the body spreads  be assigned to sound. There may also be one direct evaluation of the time course of the acceleration, e.g. B. on the signal energy possible.

In order to obtain a structure-borne sound frequency spectrum, which there is sufficient information about the brake condition finished, the structure-borne sound frequency spectra are preferred averaged over several successive measurements. Here is due to the shortness of the braking process per braking process only determined a single spectrum and then from successive individual spectra an averaged Structure-borne sound frequency spectrum formed. This is possible, since the number of braking operations up to a significant wear on the brake pad is high and therefore the time clear the brake air gap during the operating time are long enough to provide the necessary Number of individual spectra for a defined ver Obtain wear condition, from which an adequate Averaging is possible. The number of averages structure-borne sound frequency spectra used preferably at least five, most preferred is one Number of more than ten spectra provided to be at constant brake air gap a reproducible, with to obtain the structure-borne sound frequency spectrum. On Comparison of the averaged structure-borne sound frequency spectrum has shown that the amplitudes of certain Fre quota shares with increasing wear of the brake increasing and that also at higher frequencies additional spectral lines appear. These amplitudes are clearly on the change in brake air gap and thus the brake pad wear ren. But since a wear detection based on a direct spectral comparison via individual spectral compo the average structure-borne noise spectra  is difficult, is preferred in a preferred embodiment hen that the integral of the averaged structure-borne noise frequency spectrum over frequency as a measure of the ver wear of the brake pad is determined. It has been Lich surprisingly found that the integral of Amplitude spectrum over the frequency a monotonically steep dependent and therefore clear dependence on the brake air has gap and thus a clear function of the Brake air gap and thus brake pad wear represents a brake motor of fixed construction. The integral is above that which is predetermined by the measurement Frequency range determined.

Overall, such a procedure has been created by means of which a direct statement about the wear of the brake pad by measuring the changes in structure-borne noise spectrum of the brake possible with increasing wear is. There is only calibration for wear detection the brake of the respective type is necessary when new. As a result, the brake type or the motor together Frequency components of higher amplitude to be assigned to the transmission be determined. In the subsequent measurements then by means of the accelerometer Acceleration curve recorded when the brake is applied and from it by means of a fast Fourier transformation (FFT) determines the structure-borne sound frequency spectrum. Out several continuously measured and by Fourier-Trans formation of individual spectra is then a mitit tter spectrum formed. From this averaged spectrum becomes the integral over a fixed predetermined frequency range determines which for a given brake air gap is constant.  

The acceleration acceleration serving as structure-borne noise sensor In principle, users of a vibration measuring device can be placed anywhere on the engine, if these transmit the structure-borne noise of the incident brake can. It is continuous in the following Wear monitoring only to ensure that the Accelerometers always in this place is applied. The installation positions depend individually NEN each from the size of the accelerometer from. However, it is preferably provided that the acceleration sensor on the outside of the motor housing of the brake motor is arranged. The transducer can z. B. just on Terminal box can be assembled or disassembled from it, to be used in another system.

The accelerometer preferably has for measurement a piezo sensor or a strain gauge on. In the first embodiment, a change the piezoelectric charge at which second embodiment one of the resistor. Around now the measured sensor signal to the signal processing Forwarding and evaluation device is a Measuring amplifier provided so that accelerometers can be used, which are also very fast de Measure acceleration processes safely.

To process the measured structure-borne noise signals and To be able to evaluate, it is provided in further training that the signal processing and evaluation device Device for Fourier transformation of the sensor signal, a device for averaging several successive gender body determined by Fourier transformation sound frequency spectra and a device for integra tion of the spectrum obtained by averaging over the  Frequency. This can preferably be act a microcontroller who with appropriate Storage devices such as EPROM and RAM are connected.

Since that by means of the device according to the invention and frequency obtained by the method according to the invention spectrum of structure-borne noise is very broadband, is in Training provided that the accelerometer covers a frequency range between 40 Hz to 10 KHz and has a high resonance frequency.

Overall, such a method and created a device according to the invention by means of which a continuous and reliable wear Monitoring the brake lining of brake motors under Different sizes and designs of the brake possible is. It is based on the measurement of a size, namely of structure-borne noise, the measurement of which has so far been used only for general machine monitoring is to take appropriate remedial action against unwanted To be able to initiate vibrations and noises.

Further advantages and features of the invention result from the claims and from the following description exercise in which an embodiment with reference to the drawings are explained in detail. It shows:

Figure 1 is a side external view of a brake motor with arranged on the terminal box accelerator mer.

Fig. 2 is a schematic representation of a processing and evaluation device;

Fig. 3, the Körperschallfrequenz- or Be schleunigungsspektrum of a geared motor of type R82DV 132 54 BMG idle when the brake;

FIG. 4 shows the average acceleration spectrum of the geared motor from FIG. 3 when the brake is applied with an air gap of 0.3 mm;

Fig. 5 shows the averaged acceleration spectrum of the geared motor from Fig. 3 when the brake is applied with an air gap of 1.15 mm; and

Fig. 6 shows the dependence of the integral I (A (f)) of the acceleration spectrum to the frequency of the air gap δ of the geared motor in FIG. 3.

As can be seen from FIG. 1, the brake motor 1 shown in the external view has a terminal box 2 , on the outside of which an accelerometer 3 for measuring the structure-borne noise when the brake is applied is mounted. The brake is located below the fan hood 4 shown in FIG. 1.

The accelerometer 3 shown schematically in FIG. 2 transmits the sensor signals measured by it to an amplifier 5 , which is subsequently connected to an analog / digital converter 6 for converting the measured analog signals into digital signals. From this, the digital signals then reach a microcontroller 7 , which is connected to memory devices 8 , 9 (EPROM 8 , RAM 9 ). The measured signals can be stored in the memories until they are processed and evaluated by the microcontroller 7 . The microcontroller 7 uses the FFT to determine the acceleration or structure-borne noise frequency spectrum from the acceleration curve over time when the brake is applied. The spectra determined in each case can then be stored temporarily and called up after the number of measurements required for averaging has been reached. After averaging has been carried out, the averaged spectra can then be integrated by the microcontroller over a frequency range which is predetermined by the measurement. The determined inte grals are then saved depending on the brake air gap and can be called up later for evaluation.

In a specific exemplary embodiment, the result of which is shown in FIGS. 3 to 5, an accelerometer of the type AS 020 with a vibration measuring device "Vibroport 41" according to technical documentation Vibroport 41, Karl Schenk AG, Darmstadt, version 1.01, 9202 used, the accelerometer was placed on a brake motor with gear attachment type R82-DV 132 S4 BMG according to the geared motor catalog 96, SEW-EURODRIVE GmbH, Bruchsal, radially directly on the terminal box. The structure-borne sound frequency and acceleration spectra were measured under the following conditions:

  • 1. Continuous operation of the brake motor at idle with the brake released ( Fig. 3),
  • 2. Apply the brake for brake air gaps from 0.3 to 1.15 mm with the wear turned accordingly Brake pads.

The measurements were made accordingly with wear twisted brake pads carried to the long Periods until a defined wear is reached to bypass the state of the brake.

In order to be able to clearly assign the characteristic frequency components of higher amplitudes to the brake or the motor including the transmission, measurements were first carried out in continuous operation with the motor unloaded and without the influence of the brake. The average acceleration spectrum in idle mode (16 averages) is shown in Fig. 3 Darge.

When measuring the structure-borne sound frequency or acceleration spectrum with δ = 0.3 mm (corresponds to new braking condition), the spectrum shown in FIG. 4 was obtained. As can be seen from this figure, the frequency components with the largest amplitudes are around 700 Hz, 775 Hz and 1050 Hz. A secondary maximum can be seen in the range of 6.9 KHz.

The averaged spectrum for an air gap of δ = 1.15 mm (maximum wear) in FIG. 5 shows a secondary maximum at 6.9 kHz, which is 12 times larger than in FIG. 4. In addition, there are additional secondary maxima at about 2.8 kHz and 3 kHz. The comparison of the two averaged spectra in Fig. 4 and Fig. 5 shows that with increasing wear, that is, correspondingly increasing brake air gap, both the amplitudes of certain frequency components increase and spectral lines also appear at higher frequencies. The frequency bandwidth with these relatively large ampli tuden parts is about 10 KHz.

In Fig. 6 the course of the integral of the amplitude density spectrum is shown over the frequency for the facing carrier turned according to the wear. It can be seen that there is a monotonically increasing and thus clear dependence on the air gap and thus a measure of the brake wear. Due to this clear connection, continuous wear monitoring is possible.

The continuous wear monitoring is now carried out by each time the brake is applied by means of the loading Accelerometer the structure-borne noise above one predetermined time interval measured and the sensor signal forwarded to the data processing and evaluation unit is leading. From that by the accelerometer recorded acceleration course over time is then the body by means of a fast Fourier transformation sound frequency spectrum determined. Then the Spectra of successive averaging measurements subjected. The averaged spectrum is then above the Frequency integrated, which makes a direct statement about the wear becomes possible.

Claims (22)

1. A method for monitoring the wear of a brake pad in brake motors, characterized in that the structure-borne noise of the brake motor is measured at a fall of the brake and is concluded from the change in structure-borne noise on the wear of the brake pad.
2. The method according to claim 1, characterized in that that the structure-borne noise by means of a brake motor attached accelerometer measured becomes.
3. The method according to claim 2, characterized by a high sampling frequency of the accelerometer measured signal.
4. The method according to any one of claims 1 to 3, characterized characterized in that the structure-borne or Acceleration curve through fast Fourier  Transformation (FFT) the structure-borne sound frequency or Acceleration spectrum is determined.
5. The method according to claim 4, characterized in that the structure-borne sound frequency or acceleration spectra of several successive measurements be averaged.
6. The method according to claim 5, characterized in that at least five structure-borne noise or Be acceleration spectra are averaged.
7. The method according to any one of claims 4 or 5, characterized characterized that the integral of the averaged Spectrum over frequency as a measure of the ver wear of the brake pad is determined.
8. Device for monitoring the wear of a brake lining in brake motors, characterized by at least one structure-borne noise sensor ( 3 ) which emits a signal corresponding to the structure-borne noise of the brake motor to a signal processing and evaluation device ( 5 , 6 , 7 , 8 , 9 ).
9. The device according to claim 8, characterized in that the structure-borne noise sensor ( 3 ) is an acceleration sensor.
10. The device according to claim 9, characterized in that the accelerometer ( 3 ) on the motor ( 1 ) is arranged.
11. The device according to claim 9 or 10, characterized in that the accelerometer ( 3 ) on the outside of the terminal box ( 2 ) of the brake motor ( 1 ) is arranged.
12. The device according to one of claims 9 to 11, characterized in that the accelerometer ( 3 ) has a piezo sensor.
13. Device according to one of claims 9 to 11, characterized in that the accelerometer ( 3 ) has a strain gauge.
14. Device according to one of claims 8 to 13, characterized in that the signal processing and evaluation device ( 5 to 9 ) has a measuring amplifier ( 5 ).
15. The apparatus according to claim 14, characterized in that the measuring amplifier ( 5 ) with an analog / digital converter ( 6 ) is connected.
16. Device according to one of claims 8 to 15, characterized in that the signal processing and evaluation device has a device ( 7 ) for Fourier transformation of the sensor signal.
17. The apparatus according to claim 16, characterized in that the signal processing and Auswertein direction has a device ( 7 ) for averaging a plurality of successive spectra determined by Fourier transformation.
18. The apparatus according to claim 17, characterized in that the signal processing and evaluation device has a device ( 7 ) for integrating the spectrum obtained by averaging over the frequency.
19. Device according to one of claims 16 to 18, characterized in that the signal processing and evaluation device has a microcontroller ( 7 ).
20. Device according to one of claims 8 to 19, characterized in that the signal processing and evaluation device ( 5 to 9 ) Speichereinrich lines ( 8 , 9 ).
21. Device according to one of claims 8 to 20, characterized in that the accelerometer ( 3 ) covers a frequency range between 40 Hz to 10 kHz.
22. Device according to one of claims 8 to 21, characterized in that the accelerometer ( 3 ) has a high resonance frequency.
DE19626669A 1996-07-03 1996-07-03 Brake-lining wear monitoring method for brake lining of brake motor Expired - Fee Related DE19626669C1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE19626669A DE19626669C1 (en) 1996-07-03 1996-07-03 Brake-lining wear monitoring method for brake lining of brake motor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19626669A DE19626669C1 (en) 1996-07-03 1996-07-03 Brake-lining wear monitoring method for brake lining of brake motor

Publications (1)

Publication Number Publication Date
DE19626669C1 true DE19626669C1 (en) 1997-08-28

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DE19626669A Expired - Fee Related DE19626669C1 (en) 1996-07-03 1996-07-03 Brake-lining wear monitoring method for brake lining of brake motor

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19814042C1 (en) * 1998-03-30 1999-07-15 Sew Eurodrive Gmbh & Co Method of monitoring wear of brake linings in electric motors with brakes
EP1132730A1 (en) * 2000-03-07 2001-09-12 Sulzer Markets and Technology AG Method and device for determining the friction between two moving parts
US6778894B2 (en) 2001-01-08 2004-08-17 Deere & Company Monitoring device for a working vehicle
DE102004022822A1 (en) * 2004-05-08 2005-12-01 Conti Temic Microelectronic Gmbh Motor vehicle sensor, for detecting impact sound, has measured-value sensor for detecting impact sound together with sensing elements coupled to vehicle's structure
DE102004022830A1 (en) * 2004-05-08 2005-12-01 Conti Temic Microelectronic Gmbh Sensor system/trigger sensor, suitable for diagnostic safety device, especially accident protection device for motor vehicle, has elastic coupling coating/viscoelastic coupling coating for acoustic wave coupling
DE102004022831A1 (en) * 2004-05-08 2005-12-01 Conti Temic Microelectronic Gmbh Sensor system for diagnostic and safety system used to provide crash protection in an automobile
US7856880B2 (en) 2004-03-26 2010-12-28 Conti Temic Microelectronics Gmbh Vehicle sensor for detecting impact sound
DE102018219802A1 (en) * 2018-11-19 2020-05-20 Deutsches Zentrum für Luft- und Raumfahrt e.V. Method for operating an electromechanical brake and device for detecting the presence of a braking effect of an electromechanical brake

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3828932A1 (en) * 1988-08-26 1990-03-01 Teves Gmbh Alfred Method for monitoring the operation of a hydraulic, pneumatic, mechanical and/or electrical device
DE3739836C2 (en) * 1987-11-24 1991-05-16 Holec Gmbh, 4750 Unna, De
DE4116345A1 (en) * 1991-05-18 1992-11-19 Rhein Westfael Tech Ueberwach Early detection of damage in rotary machine - using single acoustic pick=up to measure structure-borne sound parameters in high and low frequency bands for calculation of coherence function

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3739836C2 (en) * 1987-11-24 1991-05-16 Holec Gmbh, 4750 Unna, De
DE3828932A1 (en) * 1988-08-26 1990-03-01 Teves Gmbh Alfred Method for monitoring the operation of a hydraulic, pneumatic, mechanical and/or electrical device
DE4116345A1 (en) * 1991-05-18 1992-11-19 Rhein Westfael Tech Ueberwach Early detection of damage in rotary machine - using single acoustic pick=up to measure structure-borne sound parameters in high and low frequency bands for calculation of coherence function

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
Meyers Lexikon der Technik und der exakten Naturwissenschaften, 1. Bd., A-E, Mannheim u. a.: Bibliographisches Institut 1969, S. 411 *
TR Technische Rundschau, Heft 5, 1993, S. 48-51 *
VDI-Berichte Nr. 368, 1980, S. 59-65 *
VDI-Richtlinien, VDI 2563 Entwurf, Ang. 1988, S. 1,11 und 12 *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19814042C1 (en) * 1998-03-30 1999-07-15 Sew Eurodrive Gmbh & Co Method of monitoring wear of brake linings in electric motors with brakes
EP0947725A2 (en) 1998-03-30 1999-10-06 SEW-EURODRIVE GMBH & CO. Method for monitoring the wear of the brake pad of a brake motor
EP1132730A1 (en) * 2000-03-07 2001-09-12 Sulzer Markets and Technology AG Method and device for determining the friction between two moving parts
US6778894B2 (en) 2001-01-08 2004-08-17 Deere & Company Monitoring device for a working vehicle
DE10100522B4 (en) * 2001-01-08 2013-03-28 Deere & Company Monitoring device for monitoring the function of a work machine
US7856880B2 (en) 2004-03-26 2010-12-28 Conti Temic Microelectronics Gmbh Vehicle sensor for detecting impact sound
DE102004022822A1 (en) * 2004-05-08 2005-12-01 Conti Temic Microelectronic Gmbh Motor vehicle sensor, for detecting impact sound, has measured-value sensor for detecting impact sound together with sensing elements coupled to vehicle's structure
DE102004022830A1 (en) * 2004-05-08 2005-12-01 Conti Temic Microelectronic Gmbh Sensor system/trigger sensor, suitable for diagnostic safety device, especially accident protection device for motor vehicle, has elastic coupling coating/viscoelastic coupling coating for acoustic wave coupling
DE102004022831A1 (en) * 2004-05-08 2005-12-01 Conti Temic Microelectronic Gmbh Sensor system for diagnostic and safety system used to provide crash protection in an automobile
DE102018219802A1 (en) * 2018-11-19 2020-05-20 Deutsches Zentrum für Luft- und Raumfahrt e.V. Method for operating an electromechanical brake and device for detecting the presence of a braking effect of an electromechanical brake

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