JP4997936B2 - Rolling bearing abnormality diagnosis device and vehicle - Google Patents

Description

  The present invention relates to an abnormality diagnosing device for diagnosing abnormalities such as scratches on vehicle bearings used for supporting the axles of vehicles such as railway vehicles and automobiles by analyzing vibrations generated by the bearings. The present invention relates to an abnormality diagnosis device having a function of detecting an abnormality of a vibration detector that detects vibration.

A conventional abnormality diagnosis technique is disclosed in Patent Document 1. The structure is such that sound or vibration generated from the object to be measured is detected by a sensor, converted into an electrical signal, A / D converted, envelope processing for obtaining the envelope (envelope) of the signal, fast Fourier transform After performing transformation (FFT) and smoothing by moving average processing of the frequency spectrum, a peak is detected, and abnormality is diagnosed based on the peak.
However, if the sensor for detecting vibration (hereinafter referred to as “vibration detector”) is abnormal, the output of the vibration detector is abnormal even though the bearing is normal. Will be determined to be abnormal. Conversely, even if the bearing abnormality diagnosis result is abnormal, there is a problem that it is not possible to trust the judgment result as it is because it is not known whether the bearing itself is abnormal or the vibration detector is abnormal. .
Japanese Unexamined Patent Publication No. 2006-113002

  The present invention has been made in view of the problems in such a conventional abnormality diagnosis apparatus, and is an abnormality diagnosis apparatus capable of detecting an abnormality of a vibration detector in a bearing abnormality diagnosis apparatus having a vibration detector. The purpose is to provide.

The present invention relates to a rotation detector for detecting the rotation speed of a rolling bearing, a vibration detector for detecting vibration of the bearing, and an A / D converter for A / D conversion of a vibration signal output from the vibration detector. An abnormality of the bearing, comprising: a D / D converter; and a bearing diagnosis processing means for performing an arithmetic process based on an output signal of the A / D converter and a rotation speed of the bearing to diagnose the abnormality of the bearing. The object of the present invention is to detect an envelope of a signal in a predetermined frequency band after performing filter processing for removing an unnecessary frequency band signal from the output signal of the A / D converter. implement envelope processing, the spectrum at that from the power spectrum obtained by frequency analyzing the obtained envelope by envelope processing, a frequency band other than the frequency bands of the wound component regarded as abnormal Calculates an average value or effective value of time, when these average or effective value is smaller than the vibration detector abnormality threshold, comprising a vibration detector diagnosis processing means for diagnosing the abnormality of the vibration detector, said bearing The diagnostic processing means is based on the average value or effective value of the spectrum intensity calculated by the vibration detector diagnostic processing means only when the vibration detector diagnostic processing means has diagnosed that the vibration detector is not abnormal. Diagnose the bearing abnormality by comparing the calculated reference value with the peak value of the spectrum intensity in the frequency band of each flaw component regarded as the abnormality extracted from the power spectrum obtained by the vibration detector diagnosis processing means. Achieved by doing

Further, the object of the present invention is effective because the peak value of the spectral intensity is a value obtained by performing arithmetic processing based on the output signal of the A / D converter and the rotational speed of the bearing. To be achieved.

Furthermore, the object of the present invention is thus the predetermined vibration detector abnormality threshold and this leading from the rotational speed of the bearing, is effectively achieved one layer.

  According to the abnormality diagnosing device according to the present invention, it is possible to diagnose the abnormality of the vibration detector based on data acquired in a conventionally performed abnormality diagnosing process. Therefore, since the abnormality diagnosis of the vibration detector can be performed without preparing a special device, the reliability of the bearing abnormality diagnosis is improved.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

[First Embodiment]
FIG. 1 is a block diagram showing a first embodiment of an abnormality diagnosis apparatus according to the present invention. In the present embodiment, a bearing to be subjected to abnormality diagnosis is, for example, a rolling bearing disposed in a vehicle bearing device that supports an axle of a railway vehicle. In the figure, a bearing 1 is rotatably arranged between an outer ring 1a fitted in a vehicle body-side housing or the like, an inner ring 1b fitted on an axle and rotating together with the axle, and an outer ring 1a and an inner ring 1b. And a plurality of rolling elements (balls or rollers) 1c.
The abnormality diagnosis device 2 according to the present invention is intended to detect the occurrence and a sign of an abnormality due to a scratch or peeling of the bearing with the rolling bearing 1 used in such a railway vehicle or the like as a diagnosis target. In FIG. 1, the abnormality diagnosis device 2 includes a detection unit 10 for detecting vibrations generated from the bearing 1 and the rotation speed of the bearing, and an operation for diagnosing the abnormality of the bearing 1 based on the output from the detection unit 10. And a processing unit 20.
The detection unit 10 performs A / D conversion on a vibration detector 11a serving as a vibration detection unit that converts vibration generated from the bearing 1 into a vibration signal that is an electrical signal, and a vibration signal output from the vibration detector 11a. / D converter 12a, rotation detector 11b as rotation speed detecting means for converting the rotation speed of bearing 1 into a rotation speed signal that is an electrical signal, and the rotation speed signal output from rotation detector 11b as A / An A / D converter 12b for D conversion is provided.
Further, the arithmetic processing unit 20 has a function of diagnosing an abnormality of the bearing 1 based on outputs from the A / D converters 12a and 12b of the detection unit 10, and in this embodiment, a railway control system and A control signal corresponding to the abnormality diagnosis result of the bearing 1 is output to the control system. In the railway vehicle control system, the diagnosis result fed back from the arithmetic processing unit 20 is constantly monitored while the vehicle is running, and when an abnormality of the bearing 1 or its sign is detected, an appropriate coping operation is performed promptly. .

FIG. 2 is a flowchart showing an example of bearing abnormality diagnosis processing due to vibration in the present embodiment.
The arithmetic processing unit 20 in the abnormality diagnosis device 2 acquires a rotation speed signal from the A / D converter 12b of the detection unit 10 (step S1), and vibration after amplitude correction from the A / D converter 12a of the detection unit 10 Data is acquired (step S2), the vibration data is subjected to frequency analysis by fast Fourier transform (FFT), the peak frequency included in the obtained power spectrum, and the bearing specifications (the number and diameter of the rolling elements 1c). Etc.) and the characteristic frequency obtained from the rotation speed of the bearing 1, and an abnormality such as peeling of the bearing 1 is detected.

Specifically, as shown in steps S3 to S15, first, the arithmetic processing unit 20 performs a filtering process for removing signals in unnecessary frequency bands from the vibration data acquired in step S2 (step S3), and then extracted. Envelope processing for detecting the envelope (envelope waveform) of the signal in the predetermined frequency band is performed (step S4). Then, frequency analysis of the envelope obtained by the envelope process is performed (step S5).
Then, a peak frequency (spectrum intensity) is extracted in the frequency band of each flaw component regarded as abnormal from the power spectrum obtained by frequency analysis (step S6).
And while calculating the average value of the spectral intensity of another frequency band (step S7), a vibration detector abnormality threshold value is calculated from the rotational speed acquired at step S1 (step S8).
Next, the average value of the spectrum obtained in step S7 is compared with the threshold value obtained in step S8. If the average value is smaller than the threshold value ("NO" in step S9), it is determined that the vibration detector is abnormal. (Step S10), information indicating that is displayed on a monitor or the like (Step S15). Further, a control signal corresponding to the diagnosis result may be output to the railway vehicle control system.

そして、前記ステップＳ１２においては、ステップＳ１１で設定した基準値と各傷成分の特徴周波数（Ｚｆｉ，Ｚｆｃ，２ｆｂ，ｆｃ）におけるスペクトルのピーク値とを比較する。
そして、各特徴周波数（Ｚｆｉ，Ｚｆｃ，２ｆｂ，ｆｃ）におけるスペクトルのピーク値が全て基準値以下であれば、軸受１は異常なしと判定する（ステップＳ１４）。一方、各特徴周波数（Ｚｆｉ，Ｚｆｃ，２ｆｂ，ｆｃ）におけるスペクトルのピーク値のいずれかが基準値を超えている場合には、軸受１に異常ありと判断し、当該特徴周波数を基に異常部位を特定し（ステップＳ１３）、その旨を示す情報をモニタ等に表示する（ステップＳ１５）。 On the other hand, if the average value is greater than or equal to the threshold value in step S9 (“YES” in step S9), the vibration detector is normal, so a reference value is calculated based on the average value of the spectrum (step S11). The reference value is compared with the peak value of the spectrum at the characteristic frequency regarded as abnormal (step S12).
Here, the characteristic frequency regarded as abnormal will be described.
The vibration frequency when a defect such as a scratch occurs in the bearing 1 varies depending on the component (each member) of the bearing 1, but the frequency band of each component regarded as abnormal is the rotational frequency fr of the inner ring 1b that rotates with the axle. It is possible to obtain based on
Table 1 below shows the defect of each member that is a component of the bearing 1, specifically, scratches and each member (the inner ring 1b, the outer ring 1a and the rolling element 1c in FIG. 1, and a cage not shown). The relationship with the abnormal vibration frequency (frequency after envelope processing) which generate | occur | produces is shown.

In step S12, the reference value set in step S11 is compared with the peak value of the spectrum at the characteristic frequency (Zfi, Zfc, 2fb, fc) of each flaw component.
If all the peak values of the spectrum at each characteristic frequency (Zfi, Zfc, 2fb, fc) are less than or equal to the reference value, it is determined that there is no abnormality in the bearing 1 (step S14). On the other hand, when any one of the peak values of the spectrum at each characteristic frequency (Zfi, Zfc, 2fb, fc) exceeds the reference value, it is determined that the bearing 1 is abnormal, and the abnormal part is determined based on the characteristic frequency. Is identified (step S13), and information indicating that is displayed on a monitor or the like (step S15).

In addition, although the average value of the spectrum of the other band is calculated in step S7, the present invention is not limited to this, and an effective value or the like may be used.
Further, in the vibration detector abnormality diagnosis process, the vibration detector abnormality threshold value is calculated from the rotational speed of the bearing in step S8. If the vibration detector fails, the spectrum average value or effective value is a small value. Therefore, the vibration detector abnormality threshold value may not be obtained from the rotation speed of the bearing but may be a fixed value.
The bearing rotation speed is obtained by AD conversion. However, the present invention is not limited to this. For example, a rotation pulse may be input to the input capture input terminal of the arithmetic processing unit.

[Second Embodiment]
FIG. 3 is a block diagram showing a second embodiment of the abnormality diagnosis apparatus according to the present invention. In the figure, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is simplified or omitted.
In the figure, an abnormality diagnosis device 2A according to the present embodiment is based on a detection unit 10A for detecting the temperature, vibration generated from the bearing 1, and the rotation state of the bearing 1, and an output from the detection unit 10A. And an arithmetic processing unit 20A for diagnosing abnormality of the bearing 1. That is, in the first embodiment described above, vibration data and rotation speed data are used as parameters for determining abnormality of the bearing 1 and the vibration detector 11a. However, in this embodiment, temperature data is further added to the bearing. 1 and the abnormality of the vibration detector 11a are determined.
The detection unit 10A includes a vibration detector 11a, an A / D converter 12a that performs A / D conversion on the vibration signal output from the vibration detector 11a, and converts the rotation state of the bearing 1 into a rotation speed signal that is an electrical signal. A rotation detector 11b as a rotation speed detecting means, an A / D converter 12b for A / D converting the rotation speed signal output from the rotation detector 11b, and a temperature signal which is an electrical signal indicating the temperature state of the bearing 1. And a temperature detector 11c as temperature detecting means for converting to a temperature detector, and an A / D converter 12c for A / D converting the temperature signal output from the temperature detector 11c.
The arithmetic processing unit 20A has a function of diagnosing an abnormality of the bearing 1 based on the quantized data output from the A / D converters 12a, 12b, and 12c of each detection unit 10A configured as described above. Yes. Note that the arithmetic processing unit 20A in the present embodiment is connected to a railway control system and outputs a control signal corresponding to the abnormality diagnosis result of the bearing 1 to the control system, as in the first embodiment. .

FIG. 4 is a flowchart showing an example of processing for diagnosing abnormality of the bearing 1 based on vibration data and temperature data. The arithmetic processing unit 20A according to the present embodiment can detect various abnormality of the bearing with higher accuracy by diagnosing the temperature state in addition to the vibration analysis processing shown in FIG.
The arithmetic processing unit 20A first sets the value M of the temperature data acquisition count to an initial value (M = 0) (step S21), and sets a threshold value for determining a temperature abnormality. This threshold is selected based on actual measurement or theoretical calculation, and is preset by, for example, an operator (step S22).

  Subsequently, an abnormality diagnosis process for the vibration detector 11a and the bearing 1 is performed according to the flowchart shown in FIG. 2 (step S23).

Next, the temperature data of the bearing 1 detected by the temperature detector 11c is acquired via the A / D converter 11c (step S24). And the influence of the noise superimposed at the time of A / D conversion is reduced by carrying out the moving average process of the acquired temperature data. The moving average processed temperature data is stored in a memory or the like (step S25). Thereafter, the value M of the temperature data acquisition count is incremented (M = M + 1) (step S26), the process returns to step S24, and the process up to step S26 is repeated. If it is determined in step S27 that the specified number of times (M = 9 in this example) has been repeated, the value of the temperature data after the moving average process is compared with the temperature abnormality threshold (step S28). And if the value of temperature data is below a threshold value, it will determine with the bearing 1 having no abnormality (step S29).
On the other hand, if the value of the temperature data exceeds the temperature abnormality threshold, it is determined that there is an abnormality in the bearing 1 (step S30), and a control signal corresponding to the diagnosis result is output to the control system of the railway vehicle. Information indicating that is displayed on a monitor or the like (step S31). Therefore, when a vibration or temperature abnormality of the bearing 1 is detected, the control signal is output to the railway vehicle control system and a diagnosis result is displayed.

  In the above-described embodiment, a case where a bearing for a railway vehicle is a diagnosis target has been described as an example. However, the bearing is not limited to a bearing for a railway vehicle, and a bearing used for all vehicles such as an automobile and a ship Can be a diagnostic target.

1 is a block diagram illustrating an abnormality diagnosis apparatus according to a first embodiment of the present invention. It is a flowchart for demonstrating the example of the abnormality diagnosis process of the bearing in 1st Embodiment. It is a block diagram which shows the abnormality diagnosis apparatus which concerns on 2nd Embodiment of this invention. It is a flowchart for demonstrating the example of the abnormality diagnosis process of the bearing by the vibration and temperature in 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bearing 2, 2A Abnormality diagnosis apparatus 10, 10A Detection part 11a Vibration detection means (vibration detector)
11b Rotational speed detection means (rotation detector)
11c Temperature detection means (temperature detector)
12a, 12b, 12c A / D converter 20, 20A arithmetic processing unit

Claims (6)

A rotation detector for detecting the rotational speed of the rolling bearing;
A vibration detector for detecting vibration of the bearing;
An A / D converter for A / D converting the vibration signal output from the vibration detector;
An abnormality diagnosis apparatus for diagnosing an abnormality in the bearing, comprising bearing diagnosis processing means for diagnosing the abnormality of the bearing by performing arithmetic processing based on an output signal of the A / D converter and a rotation speed of the bearing. In
After performing a filtering process to remove unnecessary frequency band signals from the output signal of the A / D converter, an envelope process for detecting an envelope of a signal of a predetermined frequency band is performed, and an envelope obtained by the envelope process is obtained. From the power spectrum obtained by frequency analysis , calculate the average value or effective value of the spectrum intensity in the frequency band other than the frequency band of each flaw component regarded as abnormal, and the average value or effective value is calculated from the vibration detector abnormal threshold value. A vibration detector diagnosis processing means for diagnosing an abnormality of the vibration detector when the vibration detector is smaller, and the bearing diagnosis processing means is diagnosed by the vibration detector diagnosis processing means that the vibration detector is not abnormal Only based on the average value or effective value of the spectrum intensity calculated by the vibration detector diagnostic processing means. Values and, carrying out the abnormality diagnosis of the vibration detector diagnostic processing the bearing by comparison with the peak value of the spectral intensity, the in the frequency band of each wound component regarded as the abnormality extracted from the power spectrum obtained by means An abnormality diagnosis device for a rolling bearing characterized by the following.   The rolling bearing abnormality diagnosis device according to claim 1, wherein the vibration detector abnormality threshold is derived from a rotation speed of the bearing.   The abnormality diagnosis device for a rolling bearing according to claim 1, wherein the vibration detector abnormality threshold is a preset fixed value. 4. The rolling bearing according to claim 1 , wherein the peak value of the spectral intensity is a value obtained by performing arithmetic processing based on an output signal of the A / D converter and a rotation speed of the bearing. Abnormality diagnosis device.   A temperature detector for detecting the temperature of the bearing is further provided, and the bearing diagnosis processing means diagnoses the abnormality of the bearing when the detected temperature exceeds a predetermined threshold value. 4. The abnormality diagnosis device for a rolling bearing according to any one of 4 above. A vehicle comprising the rolling bearing abnormality diagnosis device according to any one of claims 1 to 5 .

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