JP2008232934A - Facility diagnosis system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the introduction cost of a facility diagnosis system, and to provide an accurate facility diagnosis system. <P>SOLUTION: A vibration generating machine including a rotary machine among facilities installed in a factory is set as a facility to be diagnosed. The facility diagnosis system comprises a sensor 20 that is attached to the facility to be diagnosed and measures the state of vibration or the like of the facility to be diagnosed, a radio unit 30 that is connected to the sensor via a wire and is attached to the facility to be diagnosed, and a data counting analyzer that receives and counts analysis data from the radio unit and performs the state diagnosis of the facility to be diagnosed. The radio unit comprises a power supply section, a receiving section 28 for receiving a measuring signal from the sensor via a signal line, an A/D converting section 33, a processing section 35 for creating analysis data consisting of the size of a digitized measuring signal and an arithmetic value of the spectrum acquired by frequency analysis, and a transmitting/receiving section 37 for radio transmitting the analysis data and the digital waveform of the digitized measuring signal with an ID code. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a facility diagnosis system, and more specifically, detects the state of a facility with a sensor attached to the diagnosis facility, evaluates the soundness and deterioration state of the facility from a measurement signal from the sensor, and occurs in the facility. By detecting abnormalities, it prevents sudden failures of equipment and supports maintenance activities based on equipment condition monitoring standards.In particular, the processing data of signals detected by sensors is transmitted wirelessly to a data totalization analyzer. This reduces the cable laying cost and eliminates the need to remove the sensor during maintenance inspection.

For example, in the materials industry, factory equipment must be operated in an appropriate state in order to produce stable products, but as long as operation continues, the equipment will always deteriorate, and sudden failures will also occur. It is possible. Therefore, maintenance activities are necessary to maintain the equipment in good condition.
The so-called preventive maintenance activities to be performed before the equipment breaks down are roughly divided into the following two methods.
(1) Periodically stop and check the equipment (in some cases, disassemble and check the equipment), and if a deterioration or failure is found, this is a maintenance method that repairs the area. Yes.
(2) Equipment that constantly monitors the state of equipment to determine whether the equipment is in a normal state or whether an abnormality has occurred, and repairs the relevant part or replaces parts only when an abnormality is found This maintenance method is called state monitoring maintenance.

In the time-scheduled maintenance of (1), since a maintenance activity is always performed if a certain time has passed even if the equipment is in a normal state, it is inevitable that the activity will be wasted.
On the other hand, in the state monitoring and maintenance of (2), it is possible to suppress the occurrence of the above waste, but the state quantity that can accurately grasp the state of the equipment is measured, the measurement data is analyzed and the equipment is analyzed. A technology that can determine whether the device is normal or abnormal is essential, and such a technology is a facility diagnosis technology.

As equipment diagnosis technology, equipment consisting of rotating machinery measures vibration, sound, acoustic emission, temperature, etc., and increases the feature quantity and frequency information to determine bearing damage, rotational axis imbalance and misalignment, basics Equipment diagnosis that detects looseness of the gantry has been proposed.
For example, Japanese Patent Laid-Open No. 11-344332 (Patent Document 1) proposes a method for detecting a backlash of a wheel bearing portion using two distance sensors and one position sensor.

As shown in FIG. 10, the backlash detection method disclosed in Patent Document 1 is located at the same distance from the track 1 and at the heights U corresponding to the upper and lower portions of the wheel 2 facing each other across the axle 3 of the wheel 2. , L, and two laser type distance sensors 4 and 5 are arranged, and the laser is moved to a position P which is a distance from the two distance sensors 4 and 5 by the same distance and corresponding to the position of the axle 3 of the wheel 2. A system position sensor 6 is arranged.
In the above configuration, when the wheel 2 rotates, the position sensor 6 detects that the upper and lower portions of the wheel 2 have reached the positions U and L corresponding to the two distance sensors 4 and 5, and at this time, the two distance sensors 4 5 measures distances X and Y with respect to the wheel 2.
The distance sensors 4 and 5 are connected to the arithmetic processing unit 9 by the data transmission / reception line 7, and the distance data X and Y are sent to the arithmetic processing unit 9 through the amplifier 8, and the arithmetic processing unit 9 has the axle 3 of the wheel 2. An inclination amount (X−Y) and an axial movement change amount (X + Y) / 2 are calculated to diagnose the play of the wheel 2. The calculation results are accumulated in the personal computer 9a and the deterioration state is monitored over time.

In the backlash detection method, the arithmetic processing device is often arranged at a location away from the measurement location, and in Patent Document 1, since the sensor is connected to the arithmetic processing device by a data transmission / reception line, data transmission / reception is performed. There is a problem that the cost of the equipment diagnosis system rises because the cable laying work of the wire is necessary.
Furthermore, in Patent Document 1, calculation results are stored in a personal computer or the like and displayed in time series, but frequency analysis using measurement data and calculation results, abnormality diagnosis using stored data, etc. are not performed. There is a problem that detailed analysis has not been made.
In addition, in the case of equipment diagnosis system that attaches a sensor to the end of the cable and performs measurement by installing the sensor in the equipment, the cable and sensor get in the way when the equipment is repaired or parts are replaced. There is also a problem that the sensor is damaged or the cable is disconnected.

  Further, as a facility diagnosis system for factory facilities, as shown in FIG. 11, a large number of vibration sensors 100 are attached in the vicinity of a bearing 101 of a rotating machine that is a facility to be diagnosed, and measurement signals are transmitted to a relay box 101 for relay. The data is transmitted from the box 101 to the local data totaling and analyzing apparatus 102, the sensor measurement signal is processed to diagnose the equipment state, and the data is further transmitted from the totalizing / analyzing apparatus 102 to the central monitoring apparatus 103. An equipment diagnosis system is provided in which the monitoring equipment 103 collectively monitors factory equipment.

In the facility diagnosis system, cable laying from each sensor 100 to the local data totaling analysis apparatus 102 via the relay box 101 and cable laying from the local data totaling analysis apparatus 102 to the central monitoring apparatus 103 are required. Thus, since it is necessary to lay the cable, the introduction cost of the equipment diagnosis system is increased. Furthermore, since the sensor 100 and the local data totalizing and analyzing apparatus 102 are connected by a cable via the relay box 101, there is a problem in that repair or part replacement cannot be performed unless the sensor 100 is once removed from the equipment when the equipment is repaired. Will occur. At that time, errors such as breakage of the sensor 100 and disconnection of the cable may occur. In addition, there is a case where means for connecting the sensor 100 and the cable with a connector so that the sensor and the cable can be easily removed may be employed. However, the connector itself deteriorates in an environment where waterproof, dustproof and corrosion resistance are required. There is a problem that the sensor cannot be used stably for a long time.
Particularly, in the vibration sensor, since the weight of the connector must be supported by the sensor, the resonance frequency of the sensor is lowered, and vibration data in a frequency range necessary for diagnosis of the rotating machine cannot be collected accurately.

Japanese Patent Laid-Open No. 11-344332

  The present invention has been made in view of the above-described problems, and reduces the cable laying cost associated with the introduction of the equipment diagnostic system, and removes the sensor and the cable connected to the sensor from the equipment during repair and maintenance of the equipment. It is an object of the present invention to provide an equipment diagnosis system that can repair and maintain equipment without any problems and can diagnose the state of equipment with high accuracy.

In order to solve the above-mentioned problems, the present invention uses a vibration generating machine including a rotating machine among facilities installed in a factory as a diagnosis facility,
A sensor that is attached to the diagnosis facility and measures one or more states of vibration, sound, acoustic emission, and temperature of the diagnosis facility;
A wireless unit that is connected to the diagnosis facility by connecting to the sensor via an electric wire;
Receiving and totaling analysis data from the wireless unit, comprising a data totalization analysis device for performing a status diagnosis of the equipment to be diagnosed,
The wireless unit is
A power supply unit for supplying drive power from a built-in battery to the sensor via a power line;
A receiver for receiving a measurement signal from the sensor via a signal line;
An A / D converter for digitizing the received measurement signal;
A processing unit for creating analysis data composed of a calculated value of a spectrum obtained by frequency analysis and the magnitude of the digitized measurement signal;
An equipment diagnosis system is provided, comprising a transmission / reception unit that wirelessly transmits the analysis data and the digitized digital waveform of the measurement signal with an ID code.

As described above, in the equipment diagnosis system according to the present invention, the state of the equipment is measured by attaching the sensor to the diagnostic equipment, and the wireless unit connected to the sensor via the electric wire is also attached to the diagnostic equipment, A combination of a connected sensor and a wireless unit is attached to a diagnosis facility at a required position.
As described above, since each sensor-equipped equipment is connected and mounted via a sensor, a wireless unit, and an electric wire, and wirelessly transmitted from the wireless unit to the data totalization analysis device, the sensor required in the prior art system is used. The installation of cables up to the data analysis and analysis device is not required, and the cost of the equipment diagnosis system can be reduced. In addition, the cables are not obstructed during repairs and maintenance of the equipment being diagnosed. And repair and maintenance inspection are possible with the wireless unit attached to the diagnostic equipment.

In the wireless unit mounted on the diagnosis facility and connected to the sensor via the electric wire, as described above, the measurement signal (measurement data) including the analog signal received from the sensor is digitized by the A / D conversion unit, Analysis data consisting of the magnitude of the digitized measurement signal (digital waveform) and the calculated value of the spectrum obtained by frequency analysis is created in the processing unit, and this digitized analysis data is attached with an ID code along with the digital waveform. It is wirelessly transmitted to the total analysis device.
Fast Fourier transform (FFT) analysis is preferably used as a frequency analysis method performed by the wireless unit.
Also, the magnitude of the digitized measurement signal (digital waveform) is a value that represents the magnitude of the digital waveform in the amplitude direction, and is an RMS value (Root Mean Square) or an equivalent peak value (waveform). Is obtained by calculating a value obtained by multiplying a coefficient so that the average value corresponds to a half amplitude of a sine wave. The higher the RMS value or equivalent peak value, the larger the digital waveform.

That is, in the conventional example, the measurement data from the sensor is transmitted as an analog signal to the data totaling and analyzing apparatus, and the data totaling and analyzing apparatus analyzes the sensor measurement data. In the wireless unit, sensor measurement data is created as analysis data, and the analysis data is wirelessly transmitted as a digital signal to a data totalization analyzer.
Vibration, sound, and acoustic emission signals in equipment diagnosis of rotating machinery must be analyzed with a wideband frequency signal of several Hz to several hundred kHz. Especially, high-frequency analog signals exceeding 10 kHz can be analyzed from a wireless unit to a data totalization analyzer. When wireless transmission is performed with the wireless LAN, it cannot be put into practical use because it is limited by the transmission band.
However, in the present invention, since the digital waveform and the analysis data are wirelessly transmitted as a digital signal from the wireless unit to the data totalizing and analyzing apparatus, compared with the case of transmitting a high frequency analog waveform of 10 kHz or more as it is, the power consumption is low. It can be transmitted stably and can be put to practical use.
In this way, the measurement data of the sensor is digitized by the wireless unit, the magnitude and frequency spectrum of the measurement signal is calculated, and the analysis data and digital waveform of the acquired calculation value are wirelessly transmitted to the data aggregation analysis device. The data totaling and analyzing apparatus can perform state diagnosis using the accumulated analysis data and digital waveform.

In order to accurately determine the state of a diagnostic facility such as a rotating machine, it is not sufficient to determine whether there is an abnormality in the facility from a single measurement result. Changes in the state signal by comparing past data It is important to examine (called relative judgment method).
For example, even if the vibration value is at a low level, if an upward trend is seen in the last few days, it must be determined that some abnormality has occurred in the rotating machine. Furthermore, when a plurality of rotating machines of the same type are operating, it may be determined that an abnormality has occurred in the machines having a prominent difference by comparing the status signals with each other (device mutual comparison and Called diagnostic method).
Therefore, in order to accurately determine the state of the equipment, it is not possible to determine the presence or absence of an abnormality from the single measurement result and the cause of the single state signal. A reliable equipment diagnosis apparatus cannot be established without combining a sensor for measuring and a database for storing past data and having a function capable of comparing with signals of other equipment.
In the present invention, a state diagnosis is performed by the data totaling and analyzing apparatus, a database for storing past data is provided in the data totaling and analyzing apparatus, and the diagnosis result can be compared with the past data in the database and further compared with the signal of other equipment. By providing the function, highly reliable equipment diagnosis can be performed.
Furthermore, compared with the case where frequency analysis and abnormality diagnosis are performed by the data totaling analysis apparatus, since the data totaling analysis apparatus does not require an advanced calculation means, an inexpensive CPU can be used.

As described above, a vibration sensor, a temperature sensor, an acoustic sensor (such as a microphone), and an acoustic emission measurement sensor are preferably used as the sensor attached to the diagnosis facility.
For example, when the sensor is a vibration sensor, the bearing vibration can be measured to diagnose inner ring scratches, outer ring scratches, rolling element scratches, and cage defects. Alignment and tooth wear can be diagnosed. In addition, pressure pulsation and uniform wear can be diagnosed by measuring pump and fan vibrations, and high-frequency vibration and power supply imbalance can be diagnosed by measuring motor vibrations.
When the sensor is a temperature sensor, it is possible to detect an increase in temperature of a motor, a pump, a fan, or the like, and perform equipment state diagnosis.
Furthermore, the sensor can be used as a microphone or a sensor for acoustic emission measurement, and an abnormality can be diagnosed by measuring vibration noise of a bearing, pump, fan, and acoustic emission.
Further, the sensor may be attached to a plurality of locations of one diagnostic equipment and used in combination.

You may provide the monitoring apparatus which receives periodically the diagnostic result or / and analysis data which the said data totaling analysis apparatus totaled, and accumulate | stores in a database.
That is, when there is only one diagnosis facility, there is provided one data aggregation analysis device that receives analysis data from wireless units connected to sensors attached to a plurality of locations of the diagnosis facility, and the data aggregation analysis device A database may be provided to serve as a monitoring device.
However, when diagnosing a plurality of diagnosed facilities in a factory, the data totaling and analyzing device provided for each diagnosed facility is further connected to the monitoring device, and the diagnosis result or / and analysis collected by each data totaling and analyzing device The data is periodically transmitted to a monitoring device equipped with a database. In this case, the data tabulation / analysis device serves as a relay point, and it is only necessary to have a function of accumulating analysis data received from the wireless unit and periodically transmitting it to the monitoring device.

The monitoring device (data totaling analysis device when there is no monitoring device) can display the state of the equipment on the screen by the operation of the administrator or the like using the diagnosis result or / and the analysis data.
Further, diagnosis results or / and analysis data are accumulated in a database, and more detailed analysis is performed using the accumulated data.
Specifically, as described above, the past analysis data stored in the database is compared with the current analysis data, and when the change is large, a relative determination method is performed in which it is determined that an abnormality has occurred. be able to. Furthermore, in the monitoring device that receives the analysis data from each facility from the data totalization analysis device, when multiple devices of the same type and type are connected, the analysis data etc. are compared with each other, and the facility having a prominent difference Can perform an inter-equipment comparison method to determine that the device is abnormal.

The sensor to be attached to the diagnosis facility is a combination of a single wireless unit connected to one sensor via an electric wire, and a plurality of combinations of the combined sensor and wireless unit are mounted at a plurality of locations in one diagnosis facility. Yes.
Or the said sensor is mounted in the several places of one to-be-diagnosed installation, and one radio | wireless unit which attached these several sensors to the to-be-diagnosed installation is connected via the electric wire.
Either type may be used, but considering the repair of the equipment to be diagnosed, disassembly at the time of maintenance, etc., one wireless unit should be placed close to one sensor and connected via a short electric wire. Is preferred.

In addition, when the plurality of sensors are connected to the wireless unit, the wireless unit preferably includes a switch unit that selects a sensor that transmits measurement data from the plurality of connected sensors.
Since a plurality of sensors are connected to the contacts of the switch unit and a processing unit of the wireless unit is connected, the processing unit of the wireless unit selects a sensor from among the plurality of sensors for which measurement data is to be received by the switch unit. Measurement data can be received.
By connecting a plurality of sensors to one wireless unit, it is not necessary to provide a wireless unit for each sensor, and the cost of the equipment diagnosis system can be reduced.

The wireless unit may include memory means for storing a condition including at least one of the frequency analysis condition and the A / D conversion condition, and the condition may be rewritable.
The frequency analysis condition is the setting of the frequency analysis range or / and the number of averaging, and the A / D conversion condition is the setting of the sampling frequency or / and the number of sampling. Further, it may include a data measurement condition such as a data measurement time and a filtering condition for removing an unnecessary frequency band from the sensor measurement signal.
By storing the conditions in a rewritable memory means, the frequency analysis and A / D conversion conditions can be optimized for other equipment even when the equipment diagnosis system is attached to other equipment. It can be easily changed.

As described above, according to the equipment diagnosis system of the present invention, the sensor and the wireless unit are mounted in combination on the equipment to be diagnosed, and the analog signal transmitted from the sensor is digitized by the wireless unit and the digitized data is obtained. Analytical data consisting of spectrum calculation values obtained by measurement signal size and frequency analysis is created, and the digital waveform and analysis data are transmitted wirelessly to the data totalization analyzer as digital signals. It is not necessary to install a cable to the analysis device, and the cost of the equipment diagnosis system can be reduced.
In addition, since the cable is not laid, the cable does not get in the way during repair or maintenance of the diagnostic equipment to which the sensor and the wireless unit are attached, and repair and maintenance can be performed in the current state where the sensor is attached.
Furthermore, since the frequency analysis is performed in the wireless unit using the measurement data of the sensor and the state diagnosis is performed using the analysis data by the data totaling analysis apparatus, the accuracy of the state diagnosis can be improved.

Embodiments of the present invention will be described with reference to the drawings.
1 to 6 show a first embodiment of the present invention.
The facility diagnosis system 10 according to the present embodiment continuously monitors the state of a pump, which is one of rotating machines installed in a factory, and diagnoses the state.
As shown in FIG. 1, a plurality of combinations in which one vibration sensor 20 and one wireless unit 30 are connected to each other via a wire 21 are mounted on a pump facility 11 that is a diagnosis facility. 1 is provided with a single data totaling and analyzing apparatus 40 for receiving wireless transmission from the central monitoring apparatus 50 and a central monitoring apparatus 50 connected to the data totaling and analyzing apparatus 40 via a network 51.

More specifically, the pump equipment 11 is provided above the anti-load side bearing 11b, the load side bearing 11c, the coupling side bearing base 11d, and the anti coupling side bearing base 11e of the pump driving motor provided on the foundation base 11a. Vibration sensors 20A to 20D are attached.
The wireless units 30A to 30D are connected to the vibration sensors 20A to 20D, respectively, receive the measurement data of the vibration sensors 20A to 20D and convert them into digital signals, perform frequency analysis and obtain the size of the digital waveform and analyze it. The analysis data is wirelessly transmitted to the data total analysis device 40 together with the vibration digital waveform.
In addition, the data totaling analysis device 40 performs a state diagnosis of the pump facility 11 from the analysis data, and periodically transmits a diagnosis result and analysis data to the central monitoring device 50.
The central monitoring device 50 stores the diagnosis result and analysis data in a database, and diagnoses the presence or absence of abnormality of the facility and the degree of abnormality using the past analysis data accumulated in the database.

  As shown in FIG. 2, the wireless unit 30 includes a receiving unit 28, an amplifier unit 31, a filter unit 32, an A / D conversion unit 33, a buffer unit 34, and a processing unit 35 connected to the vibration sensor 20 via the signal line 21. , A storage unit 36, a transmission / reception unit 37, an antenna 38, a battery 39, and a power supply unit 29 connected to the vibration sensor 20 via the power supply line 22.

The amplifier unit 31 is connected to the receiving unit 28 and amplifies analog signal measurement data received from the vibration sensor 20 via the receiving unit 28.
The filter unit 32 is connected to the amplifier unit 31 and removes noise from the measurement data.
The A / D conversion unit 33 is connected to the filter unit 32, converts measurement data from an analog signal to a digital signal, and creates a digital waveform.
The buffer unit 34 is connected to the A / D conversion unit 33, temporarily stores the digital waveform of the vibration subjected to A / D conversion, and temporarily stores the analysis data obtained from the digital waveform.

A processing unit (CPU) 35 is connected to the buffer unit 34, sequentially reads out digital waveforms temporarily stored in the buffer unit 34, obtains the magnitude of the vibration digital waveform, and performs frequency analysis. In the present embodiment, fast Fourier transform (FFT) is performed to calculate the spectrum of the measurement data, and the analysis data is obtained.
The storage unit 36 is connected to the processing unit 35 and stores the ID of the wireless unit 30.
When the transmission / reception unit 37 is connected to the processing unit 35 and receives an analysis data transmission instruction from the data totalization analysis device 40 via the antenna 38, the analysis data and the digital waveform including the calculated values of the measurement data measured by the vibration sensor 20 are received. Is wirelessly transmitted to the data totalizing and analyzing apparatus 40 via the antenna 38.
The amplifier unit 31, the filter unit 32, the A / D conversion unit 33, the buffer unit 34, the processing unit 35, the storage unit 36, and the transmission / reception unit 37 are configured on the printed circuit board by an IC chip or the like.

  The battery 39 supplies power to the IC chip and the like on the printed board. The battery 39 is connected to the processing unit 35 and is connected to the vibration sensor 20 from the power supply unit 29 via the power line 22. When the processing unit 35 receives an instruction to transmit analysis data from the data totalization analysis device 40, the processing unit 35 issues an instruction to the battery 39 to supply power from the battery 39 to the vibration sensor 20.

The data total analysis device 40 performs primary determination of the equipment state by comparing the magnitude of vibration with a predetermined allowable level value.
As shown in FIG. 3, the antenna 41, the transmission / reception unit 42, the processing unit 43, the recording unit 44, and the interface unit (I / F unit) 45 are connected to the antenna 41 and the antenna 41. The transmission / reception unit 42 receives the analysis data transmitted from the wireless unit 30 and transmits it to the processing unit 43.
The recording unit 44 records the analysis data and the digital waveform, and also records a reference value for judging the state of the equipment from the analysis data and the digital waveform.
The processing unit 43 compares the vibration level of the reference value read from the recording unit 44 with the received analysis data, and performs a primary diagnosis of whether there is an abnormality in the equipment, and sends the diagnosis result to the network 51 via the I / F unit 45. Sending. In addition, a command to send analysis data to the wireless unit 30 is issued.

The central monitoring device 50 is composed of, for example, an operation management personal computer and includes a database B. The central monitoring device 50 is also connected via a network to other data totaling analysis devices that wirelessly receive analysis data from wireless units connected to sensors mounted in other diagnostic equipment.
That is, one data total analysis device 40 is provided for each diagnosis facility, and data from the data total analysis device 40 is collected in the central monitoring device 50.
The central monitoring device 50 periodically sums up vibration data and determination results compiled by the data summary analysis device 40, and together with the diagnosis results of other pumps (not shown), the state of the factory equipment is collectively sent to maintenance personnel. it's shown. Further, the central monitoring device 50 creates a trend management graph from the data of each vibration sensor 20 recorded in the database B. For example, the degree of increase in vibration compared to the previous result, and other pumps of the same type. If there is equipment exhibiting vibrations that are specifically deviated in comparison with the above, determine the degree of protrusion, analyze the frequency spectrum received from the local data total analysis device 40 in more detail, the presence or absence of equipment abnormality, The degree of abnormality is finally determined, and the determination result and the deterioration prediction graph are displayed.

The operation of the facility diagnosis system 10 of the present invention having the above configuration will be described with reference to the flowcharts of FIGS.
In this system, the data total analysis device 40 totals the measurement signals while sequentially scanning the plurality of vibration sensors 20. Therefore, the wireless unit 30 starts supplying power to the vibration sensor 20 in accordance with an instruction from the data totalization analysis device 40 and the power supply state is stabilized, and then the vibration digital waveform, analysis data, and ID for identifying the vibration sensor 20 are identified. The code is transmitted wirelessly.

That is, the processing unit 43 of the data totaling analysis device 40 issues a command to sequentially transmit analysis data to the four wireless units 30 (30A to 30D) (S31 in FIG. 5A).
When the wireless unit 30 receives the command (S21 in FIG. 4), the processing unit 35 of the wireless unit 30 issues a command to the battery 39 and supplies power to the vibration sensor 20 (S22). At this time, the processing unit 35 sets the measurement duration of the vibration sensor 20 to 3 seconds, for example, and issues a command to the battery 39 to supply power to the vibration sensor 20 for the measurement duration.
The vibration sensor 20 to which power is supplied measures vibration, and the wireless unit 30 receives measurement data as an analog signal from the vibration sensor 20 via the signal line 21 (S23).

The measurement data received by the wireless unit 30 via the signal line 21 and the receiving unit 28 is amplified by the amplifier unit 31, noise is removed by the filter unit 32 (S 24), and the digital signal is output by the A / D conversion unit 33. (S25). For example, FIG. 6A shows an example of a digital waveform obtained by sampling 1024 points of data at a sampling frequency of 51.2 kHz. The digital waveform is temporarily stored in the buffer unit 34, and the processing unit 35 calculates the magnitude of vibration.
In this embodiment, the RMS value is calculated as the magnitude of the vibration of the digital waveform. The RMS value is expressed by Equation (1), where T is the digital waveform measurement time.
Further, an average value may be obtained instead of the RMS value. The average value is expressed by equation (2).

Moreover, when diagnosing a bearing (rolling bearing), the filter unit 32 further performs detection processing of measurement data (S24). The detection process is a process for extracting waveform contour information, and is also referred to as an envelope process or an envelope process.
The detection waveform obtained by detecting the measurement data is an analog signal, and is converted into a digital signal by the A / D converter 33 (S25). For example, FIG. 6B is an example of a digital waveform obtained by sampling the detected waveform at 1024 points at a sampling frequency of 512 Hz.
The detected waveform that has become the digital waveform of FIG. 6B is temporarily stored in the buffer unit 34 and subjected to frequency analysis by FFT (Fast Fourier Transform) in the processing unit 35. As shown in FIG. 6C, the horizontal axis A frequency spectrum displaying the frequency and the vertical axis indicating the intensity (power) of each frequency is created (S26). In the example of FIG. 6C, the frequency analysis range of FFT is 200 Hz, and a frequency spectrum obtained by averaging four spectra.

The processing unit 35 reads the ID of the wireless unit 30 stored in the storage unit 36 (S27), the digital waveform of vibration shown in FIG. 6A, the frequency spectrum shown in FIG. 6C, and the calculated vibration. The size (RMS value) is wirelessly transmitted together with the ID to the data totalization analysis apparatus 40 via the transmission / reception unit 37 (S28).
In this way, in order to transmit the vibration waveform as a digital signal wirelessly, the signal can be stably transmitted even when a low-power wireless unit is used as compared with a case where a high-frequency analog vibration waveform of 10 kHz to 20 kHz is transmitted as it is. Can be sent.
When the transmission is completed, the processing unit 35 stops the power supply to the vibration sensor 20 and prevents the battery from being consumed.

When receiving the analysis data and the ID of the wireless unit 30 (S32 in FIG. 5A), the data totalization analysis apparatus 40 records the data in the recording unit 44 (S33).
Further, the reference value recorded in the recording unit 44 is read (S34), and compared with the analysis data, it is determined whether or not the equipment is abnormal (S35).
For example, in the case of bearing diagnosis, the characteristic frequency determined by the rotational speed of the shaft and the rating of the bearing can be uniquely determined according to the location where the bearing is damaged, so that the reference value and the analysis data received can be determined. The value of the characteristic frequency can be compared to determine the state of the equipment. In the frequency spectrum of the bearing shown in FIG. 6C received by the data totalization analyzer 40, a peak appears at approximately 80 Hz, and 80 Hz is a characteristic frequency when an outer ring flaw occurs in the bearing. By comparing the intensity of vibration at 80 Hz with a reference value, it can be diagnosed that an outer ring flaw has occurred in the bearing. The peak near 160 Hz is a secondary component of the characteristic frequency.
Moreover, since the data totalization analysis apparatus 40 has received analysis data from each of the four wireless units 30, it records each analysis data in the recording unit 44 and performs state diagnosis. These state diagnosis results are recorded in the recording unit 44 (S36).

The processing unit 43 transmits the analysis data and the diagnosis result to the central monitoring device 50, for example, at predetermined intervals every hour (S37).
When the transmission to the central monitoring device 50 is completed, the analysis data and the diagnosis result recorded in the recording unit 44 are cleared (S38).

The central monitoring device 50 receives the diagnosis result and analysis data accumulated by the data totaling analysis device 40 (S41 in FIG. 5B).
The diagnosis result and analysis data are recorded in a database (S42), and the state of the pump equipment, the digital waveform of vibration, the magnitude of vibration (RMS value), the frequency spectrum, etc. are displayed on the screen by the operation of an administrator or the like. (S43). As a result, it is possible to present data sufficient for an administrator or the like to grasp the vibration state of the pump equipment 11.
Further, the past analysis data stored in the database and the current analysis data are compared to determine the degree of increase in vibration (S44), and the pump equipment 11 is diagnosed in detail and displayed on the screen ( S45). FIG. 6D is an example of a trend management graph showing a change in vibration by combining the magnitude of past vibration and the magnitude of current vibration. In such a trend management graph, when the magnitude of vibration exceeds a predetermined level, or when there is a recent trend of increasing magnitude of vibration, the magnitude of vibration compared to other equipment of the same type The central monitoring device 50 issues an alarm when, for example, protrudes.

According to the facility diagnosis system 10 of the present invention, it is not necessary to install a cable from the facility to be diagnosed equipped with the vibration sensor 20 and the wireless unit 30 to the data totaling analysis device 40, and the cost of the facility diagnosis system can be reduced. The cable does not get in the way during the repair or maintenance of the diagnosis facility, and the repair or maintenance can be performed in the current state with the sensor attached.
Further, the measurement data is digitally converted by the wireless unit 30 attached to the diagnosis facility using the measurement data of the sensor, the frequency analysis is performed, the magnitude of the digital waveform of vibration is obtained, and the analysis data is obtained. Since the data and the digital waveform of vibration are wirelessly transmitted to the data totalization analyzer 40, wireless transmission with low power is possible. In addition, since the radio unit 30 calculates the magnitude and frequency spectrum of the status signal, the monitoring device can accurately diagnose the equipment by making use of trend management, device comparison, deterioration prediction, etc. The accuracy of diagnosis can be improved.

The present invention is not limited to the present embodiment, and a temperature sensor, a microphone, and / or an acoustic emission measurement sensor may be used instead of the vibration sensor 20.
For example, when an abnormality such as wear, delamination, or seizure occurs in a slide bearing, a remarkable change appears in the acoustic emission and the acoustic signal at the initial stage of the abnormality, and the temperature of the bearing also increases rapidly. Therefore, depending on the type of bearing, an acoustic sensor, an acoustic emission sensor, or a temperature sensor may be attached instead of the vibration sensor.

In addition, the central monitoring device 50 may be connected to other equipment in the factory where the pump equipment is installed or equipment in other places, and receives analysis data from each equipment to measure vibrations. The abnormality diagnosis result of the factory equipment including the abnormality diagnosis result of the pump equipment may be displayed collectively. Furthermore, when a plurality of equipment of the same type and the same type are connected, mutual analysis data and the like may be compared, and equipment having a prominent difference may be determined to be abnormal and displayed on the screen.
In addition, a deterioration prediction graph or the like may be displayed on the screen based on the analysis data accumulated in the database.

7 and 8 show a second embodiment of the present invention.
In the facility diagnosis system 10 of the second embodiment, one wireless unit 30 is attached to one pump facility similar to that of the first embodiment, and four units attached to a plurality of positions of the pump facility similarly to the first embodiment. The vibration sensor 20 (20A to 20D) is connected to the one wireless unit 30 via signal lines 21A to 21D (power supply lines 22A to 22D). The wireless unit 30 is attached to the upper surface of the bearing mount 11e.
As shown in FIG. 8, the wireless unit 30 is provided with a switch unit 70, and the four input contacts 70 a-1 to 70 a-4 of the switch unit 70 are connected to each vibration sensor 20 and the output contact 70 b is connected to the amplifier unit 31. Connected. The processing unit 35 is connected to the switch unit 70.

When the processing unit 43 of the data totalization analysis device 40 issues a command to transmit analysis data for, for example, the vibration sensor 20A among the four vibration sensors 20A to 20D, the processing unit 35 of the wireless unit 30 is switched to the switch unit 70. Command to connect the input contact 70a-1 and the output contact 70b to the vibration sensor 20A.
According to this embodiment, since only one radio unit 30 is provided, the number of parts of the equipment diagnosis system 10 can be reduced, and the cost is reduced.
In addition, since another structure and an effect are the same as that of 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

FIG. 9 shows a third embodiment of the present invention.
A memory card 71 as a memory means is connected to the processing unit 35 of the wireless unit 30 of the facility diagnosis system 10 of the third embodiment.
In the memory card 71, measurement conditions such as a measurement duration of vibration data, a filtering condition of the filter unit 32, a setting condition such as a sampling frequency of the A / D conversion unit 33, an FFT analysis condition, and the like are recorded. The recorded contents can be rewritten arbitrarily by a personal computer (not shown).
According to the present invention, even when the equipment diagnosis system 10 is attached to other equipment instead of pump equipment, the measurement conditions, analysis conditions, etc. of the memory card 71 are easily changed to optimum settings for other equipment. be able to.
In addition, since another structure and an effect are the same as that of 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

It is a block diagram which shows 1st Embodiment of the equipment diagnostic system which is this invention. It is a block diagram of a wireless unit. It is a block diagram of a data totalization analysis apparatus. It is a flowchart which shows operation | movement of a radio | wireless unit. (A) is a flowchart which shows operation | movement of a data totaling analysis apparatus, (B) is a flowchart which shows operation | movement of a central monitoring apparatus. (A) is an example of a digital waveform, (B) is an example of a detection processing waveform, (C) is an example of a frequency spectrum, and (D) is an example of a trend management graph. It is a block diagram which shows 2nd Embodiment. It is a block diagram of a wireless unit. It is a block diagram of the radio | wireless unit which shows 3rd Embodiment. It is a figure which shows a prior art example. It is a figure which shows another prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Equipment diagnostic system 20 (20A-20D) Vibration sensor 21 Signal line 22 Power supply line 30 (30A-30D) Wireless unit 33 A / D conversion part 35 Processing part 36 Storage part 37 Transmission / reception part 40 Data totaling analysis apparatus 43 Processing part 50 Central monitoring device 51 Network 70 Switch unit 71 Memory card

Claims (5)

Of the equipment installed in the factory, vibration generating machines including rotating machines are used as diagnostic equipment.
A sensor that is attached to the diagnosis facility and measures one or more states of vibration, sound, acoustic emission, and temperature of the diagnosis facility;
A wireless unit that is connected to the diagnosis facility by connecting to the sensor via an electric wire;
Receiving and totaling analysis data from the wireless unit, comprising a data totalization analysis device for performing a status diagnosis of the equipment to be diagnosed,
The wireless unit is
A power supply unit for supplying drive power from a built-in battery to the sensor via a power line;
A receiver for receiving a measurement signal from the sensor via a signal line;
An A / D converter for digitizing the received measurement signal;
A processing unit for creating analysis data composed of a calculated value of a spectrum obtained by frequency analysis and the magnitude of the digitized measurement signal;
A facility diagnosis system comprising: a transmission / reception unit that wirelessly transmits the analysis data and the digitized digital waveform of the measurement signal with an ID code.   The facility diagnosis system according to claim 1, further comprising a monitoring device that periodically receives the diagnosis results or / and analysis data collected by the data totaling analysis device and accumulates them in a database. A single wireless unit is connected to and combined with the one sensor via an electric wire, and a plurality of sets of the combined sensor and wireless unit are mounted at a plurality of locations in one diagnosis facility.
Or the said sensor is mounted in several places of one diagnostic equipment, and the one radio | wireless unit which attached these several sensors to the said diagnostic equipment is connected via the electric wire to Claim 1 or Claim 2 The facility diagnostic system described. The plurality of sensors are connected to the wireless unit,
The equipment diagnosis system according to claim 3, wherein the wireless unit includes a switch unit that selects a sensor that transmits measurement data from a plurality of connected sensors.   5. The wireless unit includes memory means for storing a condition including at least one of the frequency analysis condition and the A / D conversion condition, and the condition is rewritable. The facility diagnosis system according to any one of the preceding claims.

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