Vibration analysis device and abnormal part identification system equipped with the same

Abstract

The object of the present invention is to improve the accuracy of identifying a portion of a rotating body where an abnormality may exist in the vibration analysis device. [Solution] The vibration analysis device includes a control device 31 and a display device 34. The control device 31 determines candidate parts corresponding to each peak in the frequency spectrum based on a characteristic frequency caused by an abnormality in a part of the rotating body. If the frequency spectrum does not contain a second peak of a lower order than a first peak corresponding to the characteristic frequency of the specific part, the control device 31 excludes the specific part from the candidate parts and determines the remaining candidate parts as abnormal parts. The control device 31 causes the display device 34 to display the abnormal part for each peak in the frequency spectrum.

Description

[Technical Field]

[0001] The present disclosure relates to a vibration analysis device and an abnormal part identification system including the same, and more particularly to a technique for improving the accuracy of identifying an abnormal part in a rotating body. [Background technology]

[0002] As rotating parts are used, their bearings and other components may suffer from damage, wear, and other abnormalities. Therefore, abnormality diagnosis is performed on rotating parts periodically. One known method for diagnosing abnormalities in rotating parts is to analyze the vibration of the rotating parts. For example, a method is known in which signals acquired from an acceleration sensor installed in the bearing are subjected to FFT (Fast Fourier Transform) processing to extract signals of vibration-generating frequency components and identify the location of the rotating part where an abnormality exists. Vibration analyzers used for such vibration measurement generally perform frequency analysis on the signals from the acceleration sensor, and display the analysis results as a graph of acceleration for each frequency to show to the user.

[0003] Japanese Patent No. 7360887 (Patent Document 1) discloses a vibration analysis device that performs vibration analysis and indicates areas where there is a possibility of damage. Japanese Patent Application Laid-Open No. 2006-234786 (Patent Document 2) discloses an abnormality diagnosis device for mechanical equipment. These devices measure the vibration of the bearing being measured and indicate possible areas where there is an abnormality based on the frequency components of the frequency spectrum obtained by frequency analysis and the characteristic frequency of the bearing. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 7360887 [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-234786 Summary of the Invention [Problem to be solved by the invention]

[0005] The devices described in Patent Documents 1 and 2 present candidates for areas where an abnormality exists based on the peaks of the frequency spectrum. Therefore, regardless of the user's level of proficiency, the user can recognize the candidates for areas where an abnormality exists based on the presented content. However, Patent Documents 1 and 2 do not consider the validity of the candidates for areas where an abnormality exists identified by the device. Therefore, the user must identify the area where an abnormality exists from the presented candidates, and depending on the user's level of proficiency, it may be difficult to identify the area where an abnormality exists.

[0006] An object of the present disclosure is to improve the accuracy of identifying abnormal parts in a vibration analysis device that receives measurement data from a measuring instrument that measures the vibration of a rotating body that is the measurement target, and presents abnormal parts that are parts of the rotating body that may be abnormal. [Means for solving the problem]

[0007] A vibration analysis device according to one aspect of the present disclosure receives measurement data from a measuring instrument that measures the vibration of a rotating body and identifies an anomalous portion of the rotating body that may be abnormal, and includes a control device and a display device. The control device receives information about the rotating body and performs frequency analysis of the measurement data. Based on the information, the control device calculates each of the characteristic frequencies that arise due to an abnormality in each portion of the rotating body, and determines, based on each of the characteristic frequencies, a candidate portion corresponding to each peak in the frequency spectrum obtained by the frequency analysis. If a first peak corresponding to the characteristic frequency of the specific portion is present in the frequency spectrum and a second peak corresponding to the characteristic frequency of the specific portion and having a lower order than the first peak is not present in the frequency spectrum, the control device excludes the specific portion from the candidate portions and determines the remaining candidate portions as anomalous portions. The control device displays the determined anomalous portion for each peak in the frequency spectrum on the display device.

[0008] A vibration analysis device according to another aspect of the present disclosure receives measurement data from a measuring instrument that measures vibrations of a rotating body and identifies anomalous parts that are candidates for parts of the rotating body that may be abnormal. The vibration analysis device includes a control device and a display device. The control device receives information about the rotating body and an allowable width for each characteristic frequency that arises due to an abnormality in each part of the rotating body, calculated based on the information. The control device performs frequency analysis of the measurement data to calculate each characteristic frequency, and determines the anomalous part based on whether the frequency of each peak in the frequency spectrum obtained by the frequency analysis is within the allowable width. When one or more parts are determined to be anomalous parts for a fourth peak included in the frequency spectrum, the control device calculates a difference between each characteristic frequency of the one or more parts and the frequency of the fourth peak. The control device causes the display device to display the one or more parts as anomalous parts in a manner based on the difference for the fourth peak. [Effects of the Invention]

[0009] According to the vibration analysis device according to the present disclosure, it is possible to improve the accuracy of identifying an abnormal portion of a rotating body that is the measurement target. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram illustrating a configuration of an abnormality portion identification system. [Figure 2] FIG. 2 is a diagram illustrating the configuration of a measuring device. [Figure 3] FIG. 1 is a diagram illustrating a configuration of a portable information terminal. [Figure 4] FIG. 10 is a diagram for explaining the contents of a first process. [Figure 5] FIG. 10 is a diagram for explaining the contents of a second process. [Figure 6] FIG. 10 is a diagram showing an example of display on a display device. [Figure 7] FIG. 10 is a diagram for explaining the content of a third process. [Figure 8] FIG. 10 is a diagram showing another example of display by the display device. [Figure 9]FIG. 10 is a diagram illustrating an example of setting information input by an input device. [Figure 10] 10 is a flowchart showing an example of a processing procedure in the measuring device. [Figure 11] 10 is a flowchart illustrating an example of a processing procedure in a portable information terminal. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, the present embodiment will be described in detail with reference to the drawings, in which the same or corresponding parts are designated by the same reference numerals and description thereof will not be repeated.

[0012] [Configuration of the abnormal part identification system] 1 is a diagram showing an abnormal part specifying system according to the present embodiment. Referring to FIG. 1, abnormal part specifying system 10 includes measuring instrument 20 and mobile information terminal 30.

[0013] Measuring instrument 20 is a device for measuring vibrations occurring in rolling bearing 15, which is the measurement target, and is configured to include an acceleration sensor (not shown) for detecting vibrations. Measuring instrument 20 is configured to be able to communicate wirelessly with mobile information terminal 30, and upon receiving a measurement start signal from mobile information terminal 30, it detects vibrations occurring in rolling bearing 15 using the acceleration sensor. Measuring instrument 20 then transmits acceleration data detected by the acceleration sensor to mobile information terminal 30. Note that measuring instrument 20 may also be connected to mobile information terminal 30 by wire so as to be able to communicate with it.

[0014] The mobile information terminal 30 is the "vibration analysis device" in the present disclosure, and receives measurement data (vibration acceleration data) from the measuring instrument 20 and analyzes the vibration occurring in the rolling bearing 15. The mobile information terminal 30 is a terminal that can be used by a user of the abnormal part identification system 10, and is, for example, a smartphone or a tablet. Application software running on the mobile information terminal 30 allows the mobile information terminal 30 to be used as the "vibration analysis device."

[0015] Fig. 2 is a diagram showing the configuration of measuring device 20. Referring to Fig. 2, measuring device 20 includes an acceleration sensor 102, an anti-aliasing filter 104, an A / D converter 106, a microcomputer 108, a memory 110, and a communication module 112.

[0016] Acceleration sensor 102 is attached to rolling bearing 15 (FIG. 1) that is the measurement target, and detects and outputs the acceleration of vibrations occurring in rolling bearing 15. Anti-aliasing filter 104 is a low-pass filter for suppressing aliasing errors that occur during A / D conversion in A / D converter 106. A / D converter 106 converts the measurement signal (analog signal) that has passed through anti-aliasing filter 104 into a digital signal.

[0017] Microcomputer 108 receives the acceleration data converted into a digital signal by A / D converter 106 and outputs it to memory 110. Then, when a predetermined amount of data has been accumulated in memory 110, microcomputer 108 reads the accumulated data from memory 110 and transmits it to mobile information terminal 30 via communication module 112 as measurement data from measuring instrument 20.

[0018] Memory 110 receives from microcomputer 108 acceleration data converted into a digital signal by A / D converter 106 and temporarily stores the data. Communication module 112 is a wireless module that enables measuring instrument 20 to communicate with portable information terminal 30.

[0019] 3 is a diagram showing the configuration of the mobile information terminal 30. The mobile information terminal 30 includes a control device 31, a display device , an input device 35, and a communication device .

[0020] The control device 31 includes a processor 32 and a memory 33. The processor 32 is, for example, a CPU (Central Processing Unit), and is a processing circuitry that executes predetermined arithmetic processing described in a program. The processor 32 reads out the program and data stored in the memory 33, and identifies a portion of the rolling bearing 15, which is the object of measurement by the measuring instrument 20, that is likely to have an abnormality.

[0021] The memory 33 includes non-volatile or volatile memory such as a read-only memory (ROM) or a random access memory (RAM), and / or a large-capacity storage device such as a hard disk drive (HDD) or a solid state drive (SSD). The memory 33 stores, for example, programs for executing the various processes performed by the processor 32, information received from the input device 35, and acceleration data generated by the measuring instrument 20.

[0022] The control device 31 is connected to a display device 34, an input device 35, and a communication device 36. Display device 34 is, for example, a liquid crystal display (LCD) or an organic electroluminescence (EL) display. Control device 31 causes display device 34 to display the measurement results of measuring device 20 and the candidate and / or abnormal areas identified by processor 32.

[0023] The input device 35 is, for example, a keyboard, a mouse, a pointing device, a touch panel, etc., and receives operations from the user.

[0024] Communication device 36 is a device that enables mobile information terminal 30 to communicate wirelessly with measuring instrument 20. In accordance with instructions from control device 31, communication device 36 transmits a measurement start signal to measuring instrument 20 when vibration measurement by abnormal part identification system 10 begins. Communication device 36 also receives measurement data transmitted from measuring instrument 20.

[0025] The control device 31 receives information relating to the rolling bearing 15 to be measured via the input device 35. In this embodiment, the information to be set is input by the user from the screen of the mobile information terminal 30, but it may also be stored in advance in the memory 33 and read out by the control device 31 from the memory 33 when vibration measurement by the abnormal part identification system 10 begins. Information relating to the rolling bearing 15 is, for example, the bearing model number of the rolling bearing 15, and the rotational speed or rotational frequency of the rolling bearing 15 during measurement by the measuring instrument 20.

[0026] In this embodiment, specification data for various bearings whose vibrations can be measured by the abnormal part identification system 10 is associated with the bearing model number and stored in advance in the memory 33. The control device 31 then reads out the specification data for the bearing from the memory 33 using the bearing model number received from the input device 35 as an index. Note that the specification data for the rolling bearing 15 may also be input from the input device 35 as information about the rolling bearing 15.

[0027] The control device 31 also receives a judgment reference value for judging the vibration state of the rolling bearing 15 that is the measurement target. In this embodiment, this judgment reference value is also input by the user from the screen of the mobile information terminal 30, but it may also be stored in advance in the memory 33 and read from the memory 33 when the abnormal part identification system 10 starts vibration measurement.

[0028] The control device 31 performs frequency analysis on the measurement data received from the communication device 36. As an example, the control device 31 performs FFT processing on the time-series acceleration data received from the communication device 36 to generate a frequency spectrum of the measurement data.

[0029] The memory 33 stores specification data of various bearings whose vibrations can be measured by the abnormality part identification system 10, in association with the bearing model number. In this embodiment, the specification data includes data from which frequencies observed when an abnormality occurs in each part of the rotating body can be calculated. Specifically, the specification data includes at least data from which the ball pass frequency of inner ring (BPFI), ball pass frequency of outer ring (BPFO), and ball spin frequency (BSF) shown in the following equations (1) to (3) can be calculated.

[0030]

number

[0031] Here, D is the pitch diameter of the bearing, d is the diameter of the rolling elements, α is the contact angle of the rolling elements, and Z is the number of rolling elements. Note that f0 is the rotation frequency of the shaft, which is received by the control device 31 via the input device 35, or, if the rotation speed is set by the control device 31, is calculated from that rotation speed.

[0032] Memory 33 stores at least the specification data of the pitch circle diameter D, rolling element diameter d, rolling element contact angle α, and number of rolling elements Z, in association with the bearing model number. Note that instead of these specification data, coefficients Cin, Cout, and Crol of rotational frequency f0 for calculating BPFI, BPFO, and BSF, respectively, may be stored in memory 33. The coefficients Cin, Cout, and Crol are expressed by the following equations (4) to (6).

[0033]

number

[0034] The control device 31 calculates the BPFI, BPFO, and BSF of the rolling bearing 15 at the time of measurement based on the received information about the rolling bearing 15. Specifically, the control device 31 reads from the memory 33 the specification data of the bearing corresponding to the bearing model number received via the input device 35, and calculates the BPFI, BPFO, and BSF using the read specification data and the set rotational speed (or rotational frequency) using the above formulas (1) to (3).

[0035] The control device 31 identifies candidate parts, which are parts where there is a possibility that an abnormality may exist, for each peak in the frequency spectrum of the measurement data received from the measuring device 20. In this process, the tolerance included in the information received from the input device 35 is used. Specifically, for a peak whose frequency in the frequency spectrum (hereinafter referred to as the "peak frequency") falls within a tolerance range set based on the tolerance ranges of BPFI and its higher-order components, the inner ring is assumed to have a defect, and the inner ring is identified as the candidate part. For a peak whose peak frequency falls within the tolerance ranges of BPFO and its higher-order components, the outer ring is identified as the candidate part, and for a peak whose peak frequency falls within the tolerance ranges of BSF and its higher-order components, the rolling element is identified as the candidate part.

[0036] Furthermore, if the peak frequency is included in the allowable range of the shaft rotation frequency and its higher-order components, it is estimated that shaft imbalance has occurred. If the peak frequency is included in the allowable range of twice the rotation frequency and its higher-order components, it is estimated that misalignment has occurred. Therefore, if the peak frequency is included in the allowable range of the shaft rotation frequency and its higher-order components, processor 32 determines that there is a malfunction in the rotating shaft and identifies the rotating shaft as a candidate part. As described above, in this embodiment, not only are the bearing parts (inner ring, outer ring, rolling elements) corresponding to BPFI, BPFO, and BSF identified as candidate parts corresponding to the peaks, but also malfunctions of the rotating shaft caused by shaft imbalance and misalignment are identified.

[0037] In this specification, frequencies caused by damage to the inner ring, outer ring, and rolling elements, and frequencies caused by shaft imbalance and misalignment are referred to as characteristic frequencies. Candidate parts are identified based on the presence or absence of a peak whose frequency falls within an allowable range that is set based on the characteristic frequency and the allowable width.

[0038] The control device 31 judges the vibration state for each peak based on the peak value, which is the acceleration of the peak in the frequency spectrum, and the judgment reference value. For example, the control device 31 judges a peak whose peak value exceeds the judgment reference value as "danger." Furthermore, the control device 31 judges a peak whose peak value is lower than the judgment reference value but exceeds 80% of the judgment reference value as "caution," and judges a peak whose peak value is lower than 80% of the judgment reference value as "good."

[0039] [Comparative Example] When rotating parts are used, their bearings and other parts may suffer from damage, wear, or other abnormalities. For this reason, abnormality diagnosis of rotating parts is performed periodically. One known method for diagnosing abnormalities in rotating parts is to analyze the vibration of the rotating parts. Vibration analyzers used for vibration measurement generally perform frequency analysis of signals from an acceleration sensor, and display the analysis results as a graph of acceleration for each frequency, which can be shown to the user.

[0040] Conventional vibration analysis devices, such as those disclosed in Patent Documents 1 and 2, measure the vibration of a bearing to be measured, extract a predetermined number of peaks from the largest peak values ​​in the frequency spectrum obtained by frequency analysis, and present candidate damaged areas based on the characteristic frequencies of the bearing. However, if the specifications of the bearing to be measured differ from those expected, or if the rotational speed fluctuates and the frequency changes, an area that does not actually have an abnormality may be selected as the abnormal area. While an experienced user can refer to the display of the vibration analysis device and determine the validity of the displayed content, it may be difficult for an inexperienced user to determine the validity of the displayed content. Therefore, it is desirable to improve the accuracy of identifying abnormal areas in a vibration analysis device.

[0041] [Vibration analysis device according to the embodiment] Therefore, the portable information terminal 30, which is a vibration analysis device according to this embodiment, identifies candidate abnormal parts by comparing the frequencies of the peaks in the frequency spectrum obtained by frequency analysis with the characteristic frequencies derived from each part, and then excludes from the candidate abnormal parts those parts that are unlikely to be abnormal parts and identifies the remaining candidate abnormal parts as abnormal parts.The portable information terminal 30 then presents the abnormal parts from which the parts unlikely to be abnormal have been excluded to the user.The display on the portable information terminal 30 allows the user, regardless of the user's level of proficiency, to recognize parts that are likely to be abnormal.

[0042] Furthermore, when the portable information terminal 30, which is the vibration analysis device according to this embodiment, identifies that one peak in the frequency spectrum is a peak caused by abnormalities in two or more different parts, it determines priorities for the two or more parts.The portable information terminal 30 then presents the two or more parts to the user so that the user can recognize the priorities.When it is identified that one peak in the frequency spectrum is caused by abnormalities in two or more parts, the display on the portable information terminal 30 allows the user to recognize which part is more likely to have an abnormality.

[0043] The following describes three processes performed by the mobile information terminal 30 according to the present disclosure and the content displayed on the display device 34 after the three processes.

[0044] <First process> The control device 31 identifies a candidate region for each peak based on the peak frequency and feature frequency of each peak in the frequency spectrum of the measurement data received from the measuring device 20. The control device 31 selects an abnormal region from the identified candidate regions that is highly likely to be an abnormal region. Specifically, when a peak frequency is identified as a high-order component of the feature frequency of a predetermined region, the control device 31 determines whether the peaks in the frequency spectrum include a peak identified as a low-order component of the feature frequency of the predetermined region. When the peaks in the frequency spectrum do not include a peak corresponding to a low-order component of the feature frequency of the predetermined region, the control device 31 excludes the predetermined region from the candidate regions and does not select it as an abnormal region.

[0045] Fig. 4 is a diagram for explaining the first process executed in control device 31. Fig. 4 shows an example of a frequency spectrum generated by performing FFT processing on time-series acceleration data measured by measuring instrument 20.

[0046] In FIG. 4, assume that the frequency of peak P1 is included in the allowable range of the outer ring's second-order component. In this case, processor 32 checks whether the frequency spectrum contains a peak that is included in the allowable range of the outer ring's first-order component, which is lower than the outer ring's second-order component. If control device 31 confirms that peak P2 is detected within the allowable range of the outer ring's first-order component, it determines that peak P1 corresponds to the outer ring's second-order component. On the other hand, if control device 31 cannot confirm peak P2 within the allowable range of the outer ring's first-order component, it determines that peak P1 does not correspond to the outer ring's second-order component. Therefore, if peak P2 cannot be confirmed within the allowable range of the outer ring's first-order component, even if peak P1 is confirmed within the allowable range of the outer ring's second-order component, the "outer ring" is excluded from the candidate parts and is not selected as an abnormal part.

[0047] <Second process> When the control device 31 determines that the frequency spectrum includes the peak of the high-order component of a predetermined region and the peak of the low-order component of the predetermined region, it determines whether the peak value of the high-order component is equal to or less than the peak value of the low-order component. If the peak value of the high-order component is not equal to or less than the peak value of the low-order component, the control device 31 excludes the predetermined region from the candidate regions.

[0048] Fig. 5 is a diagram for explaining the second process executed in control device 31. Fig. 5 shows an example of a frequency spectrum generated by control device 31 performing FFT processing on the time-series acceleration data measured by measuring instrument 20.

[0049] In Figure 5, the frequency of peak P3 is included in the allowable range of the outer ring secondary component, and the frequency of peak P4 is included in the allowable range of the outer ring primary component. At this time, the control device 31 compares α, which is the peak value of peak P3, with β, which is the peak value of peak P4. In Figure 5, β, which is the peak value of the lower-order peak P4, is smaller than α, which is the peak value of the higher-order peak P3. Therefore, even if peak P4 is confirmed within the allowable range of the outer ring primary component and peak P3 is confirmed within the allowable range of the outer ring secondary component, the "outer ring" is excluded from the candidate parts and is not selected as an abnormal part.

[0050] Fig. 6 is a diagram showing an example of a display screen that the control device 31 causes the display device 34 to display. Fig. 6 shows the screen of the display device 34 on which display information is displayed.

[0051] Referring to FIG. 6, in this example, for peaks having the top 10 peak values, the peak values ​​(acceleration), peak frequencies, judgment results, and abnormal parts are displayed in descending order of peak value (a1>a2>···>a10).

[0052] In FIG. 6, the frequency of the fifth-largest peak is included in the inner ring's second-order tolerance range. However, none of the four peaks with higher peak values ​​than this peak is included in the inner ring's first-order tolerance range. Therefore, the inner ring is excluded from the candidate parts by the second process. As a result, when the control device 31 presents abnormal parts to the user, the "inner ring" is not displayed as an abnormal part.

[0053] The first process and the second process are performed based on the fact that when an abnormality occurs in a predetermined part of the rotating body, the first-order component of the characteristic frequency of the part has the largest acceleration, and the peak acceleration decreases as the order of the characteristic frequency increases. Note that whether or not to perform the first process and the second process may be determined based on a user instruction.

[0054] By executing the first process and the second process, the abnormal part identification system 10 can present to the user the parts that are highly likely to have an abnormality. This allows the user to easily grasp the parts of the measurement object that are highly likely to be damaged, without the need to search for peaks of different orders from the detected peak in the display results or to read values ​​from a frequency spectrum graph.

[0055] When misalignment occurs, a frequency twice the rotation frequency and / or its higher-order components are detected as a peak frequency. Therefore, when misalignment occurs, the frequency spectrum may contain a peak at twice the rotation frequency, but no peak at a frequency corresponding to the rotation frequency. In such a case, when the first process and / or the second process are performed, the "rotating axis" corresponding to the misalignment may not be identified as an abnormal part. Therefore, when the rotating axis is identified as a candidate part, the first process and the second process may not be applied. Note that when it is determined that no misalignment occurs, the peaks of the shaft rotation frequency and its higher-order components that fall within the respective allowable ranges may also be applied to the first process and the second process in order to improve the accuracy of unbalance determination.

[0056] <Third Processing> When a predetermined peak in the frequency spectrum is identified as being due to abnormalities in multiple parts, the control device 31 calculates the difference between the peak frequency of the predetermined peak and the characteristic frequency of each of the multiple parts, and determines the priority of the multiple parts based on the difference.

[0057] Fig. 7 is a diagram for explaining the third process executed by control device 31. Fig. 7 shows an example of a frequency spectrum generated by performing FFT processing on the time-series acceleration data measured by measuring instrument 20.

[0058] 7, peak P5 is included in both the allowable range of the inner ring primary and the allowable range of the outer ring secondary. Here, control device 31 calculates the difference X between the frequency c of peak P5 and the characteristic frequency a of the inner ring primary, and the difference Y between the frequency c of peak P5 and the characteristic frequency b of the outer ring secondary. Because difference Y is smaller than difference X, control device 31 determines that the outer ring secondary has a higher priority as an abnormal part of peak P5 than the inner ring primary.

[0059] Fig. 8 is a diagram showing an example of a display screen displayed on the display device 34. Fig. 8 shows the screen of the display device 34.

[0060] Referring to FIG. 8, the frequency of the peak with the fifth-largest peak value is included in the allowable range of the inner ring primary and the allowable range of the outer ring secondary. The control device 31 calculates the difference X between the peak frequency of the fifth-largest peak value and the characteristic frequency of the inner ring primary, and the difference Y between the peak frequency of the fifth-largest peak value and the characteristic frequency of the outer ring secondary. If the difference Y is smaller than the difference X, the control device 31 determines that the outer ring secondary has a higher priority than the inner ring primary as an abnormal part of peak P5. In the above case, the control device 31 displays the "outer ring secondary," which has a higher priority, above the "inner ring primary" on the display device 34 as a candidate part for the peak with the fifth-largest peak value.

[0061] By executing process 3, when there are multiple abnormal parts corresponding to one peak, the vibration analysis results are displayed based on priority, allowing the user to easily determine which part is most likely to be damaged.

[0062] In FIG. 8, abnormal areas are displayed in descending order of priority, but the display is not limited to this. For example, the control device 31 may change the size of the characters in descending order of priority, or change the color of the area according to the priority.

[0063] [Information to be set] Fig. 9 is a diagram showing an example of information received by the control device 31 via the input device 35. The information received by the control device 31 can be input by the user via the input device 35, and Fig. 9 shows a screen displayed on the display device 34 for the user to input the information.

[0064] 9, the user can input the bearing model number of the rolling bearing 15 (FIG. 1) to be measured from input unit 410. In FIG. 9, input unit 410 shows that "6206LLB" has been input as the bearing model number.

[0065] The user can input the rotation speed (rpm) of the shaft during measurement through input unit 420. Note that this abnormal area identification system 10 is not provided with a sensor for detecting the rotation speed of the shaft during measurement by measuring instrument 20, so it is necessary to obtain rotation speed information during measurement and input it through input unit 420. However, if a rotation speed sensor is provided, input unit 420 is not necessary. Furthermore, the user may input the rotation frequency of the shaft during measurement into input unit 420 instead of the rotation speed of the shaft during measurement.

[0066] The user can input a judgment reference value (acceleration) from input unit 430. In this embodiment, the judgment reference value is a uniform value regardless of the peak frequency.

[0067] The user can input the allowable range of the feature frequency through input unit 440 and input unit 445. The user can input the lower limit of the allowable range into input unit 440 and the upper limit of the allowable range into input unit 445. For example, as shown in Fig. 9, when "10" is input into input unit 440 and "5" is input into input unit 445, and the feature frequency of a predetermined part is "300", processor 32 sets 270 to 315 as the allowable range for the predetermined part, and determines that a peak included in the allowable range is a peak corresponding to the predetermined part.

[0068] The user can input the number of top peak values ​​to be displayed on the display device 34 from the input unit 450. The number of peaks to be displayed is set according to this input value. If there is no input from the input unit 440, a default value (for example, 10) is set.

[0069] The user can input whether or not the first process is to be executed from input unit 460. When "ON" is selected in input unit 460, the first process is executed, and when "OFF" is selected, the first process is not executed.

[0070] The user can input whether or not the second process is to be executed from input unit 470. If "ON" is selected in input unit 470, the second process is executed, and if "OFF" is selected, the second process is not executed.

[0071] The user can input whether or not the third process is to be executed from input unit 480. When "ON" is selected in input unit 480, the third process is executed, and when "OFF" is selected, the third process is not executed.

[0072] The user can set whether to execute the second process independently of the execution of the first process. If the second process is executed without executing the first process, for example, if the frequency spectrum has a peak corresponding to the outer ring secondary but no peak corresponding to the outer ring primary, the control device 31 cannot acquire the peak value of the peak corresponding to the lower order of the outer ring secondary, and therefore cannot execute the second process, and the outer ring secondary is not excluded from the candidate parts.

[0073] [Processing flow in the measuring device] 10 is a flowchart showing an example of the processing procedure in measuring device 20. Referring to FIG. 2 together with FIG. 10, when measuring device 20 is powered on, microcomputer 108 executes a predetermined initialization process (step S10). The initialization process includes, for example, establishing communication between communication module 112 and mobile information terminal 30, clearing data in memory 110, and the like.

[0074] Next, microcomputer 108 determines whether or not a measurement start signal has been received from portable information terminal 30 (step S12). If the measurement start signal has been received (YES in step S12), microcomputer 108 reads from A / D converter 106 the output of acceleration sensor 102 that has passed through anti-aliasing filter 104 and been digitally converted by A / D converter 106 (step S14).

[0075] The microcomputer 108 transmits the acquired data to the mobile information terminal 30 via the communication module 112 (step S16).

[0076] Next, microcomputer 108 determines whether or not a termination operation to terminate measurement has been performed by the user (step S18). The termination operation is performed on mobile information terminal 30, and for example, when a measurement termination signal is received from mobile information terminal 30, it is determined that the termination operation has been performed.

[0077] If it is determined that the termination operation has not been performed (NO in step S18), the process returns to step S10. On the other hand, if it is determined that the termination operation has been performed (YES in step S18), the process proceeds to END, and the series of processes in measuring device 20 ends.

[0078] [Processing flow in mobile terminal device] 11 is a flowchart showing an example of a processing procedure in mobile information terminal 30. Referring to FIG. 3 together with FIG. 11, when application software for performing vibration measurement using measuring instrument 20 is started on mobile information terminal 30 and an instruction to start measurement is given in the application software, processor 32 executes a predetermined initialization process (step S30). The initialization process includes, for example, establishing communication with measuring instrument 20 and performing a predetermined reset process.

[0079] Next, based on the information received via the input device 35, the processor 32 sets the bearing model number of the rolling bearing 15 to be measured, the rotational speed (or rotational frequency) during measurement, the judgment reference value for judging the vibration state based on the measurement data, the tolerance range, the number of peaks to be acquired, and whether or not to execute the first to third processes (step S32).

[0080] Next, processor 32 reads out from memory 33 the specification data of the bearing corresponding to the set bearing model number, and calculates the characteristic frequency of rolling bearing 15 to be measured using the specification data and the rotational frequency calculated from the set rotational speed, using the above equations (1) to (3) (step S34). Processor 32 calculates the allowable range for each part based on the values ​​calculated in step S34 and the allowable range input by the user in step S32 (step S36). Thereafter, processor 32 causes communication device 36 to send a measurement start signal to measuring instrument 20 (step S38).

[0081] When the measurement start signal is sent to measuring device 20, processor 32 determines whether measurement data has been received from measuring device 20 (step S40). If measurement data is received from measuring device 20 (YES in step S40), processor 32 stores the received measurement data in memory 33 (step S42). If measurement data cannot be received from measuring device 20 (NO in step S40), processor 32 repeats the process of step S38.

[0082] Processor 32 reads data from memory 33 and performs frequency analysis on the data measured by measuring instrument 20 (step S44). Specifically, FFT processing is performed on the time-series acceleration data measured by measuring instrument 20 to obtain a frequency spectrum of the measured acceleration data. Processor 32 extracts peaks from the obtained frequency spectrum in descending order of acceleration, and obtains the peak accelerations and peak frequencies of the extracted peaks (step S46). Processor 32 determines whether the number of peaks for which the peak accelerations and peak frequencies have been obtained has reached a set number of peaks (step S48), and if the number of peaks for which the peak accelerations and frequencies have been obtained has not reached the set number of peaks (NO in step S48), the process of step S46 is repeated.

[0083] In step S50, if the number of peaks for which the peak accelerations and peak frequencies have been obtained reaches the set number of peaks (YES in step S48), the processor 32 determines the vibration state of each peak based on the judgment reference value set in step S32 and the peak acceleration of the peak obtained in step S46.

[0084] Next, for the peaks extracted in step S46, processor 32 identifies candidate parts corresponding to the peak frequencies of each peak. Specifically, for each extracted peak, processor 32 identifies candidate parts for that peak depending on whether the peak frequency is within the allowable range for that part (step S52). Candidate parts are, for example, parts of rolling bearing 15 (inner ring, outer ring, and rolling elements), and rotating shafts that exhibit abnormalities due to shaft imbalance and misalignment.

[0085] If processor 32 has identified a candidate site for the peak extracted in step S46 (YES in step S52), processor 32 causes display device 34 to display the candidate site (step S54). If processor 32 has not identified a candidate site (NO in step S52), processor 32 proceeds to step S68.

[0086] Next, processor 32 determines whether or not execution of the first process was set in step S32 (step S56). If execution of the first process was set (YES in step S56), processor 32 executes the first process (step S58). Specifically, processor 32 excludes from the candidate regions identified in step S52 any region in which a peak of a higher-order component was detected but no peak of a lower-order component was detected. If execution of the first process was not set (NO in step S56), processor 32 proceeds to step S60 without executing the first process.

[0087] Processor 32 determines whether or not execution of the second process has been set in step S32 (step S60). If execution of the second process has been set (YES in step S60), processor 32 executes the second process (step S62). Specifically, for a region in which a peak of a lower-order component corresponding to a peak of a higher-order component has been detected, among the candidate regions identified in step S52, if the peak value of the peak of the lower-order component is equal to or less than the peak value of the peak of the higher-order component, processor 32 excludes the region from the candidate regions. If execution of the second process has not been set (NO in step S60), processor 32 proceeds to step S64 without executing the second process.

[0088] Processor 32 determines whether or not execution of the third process is set in step S32 (step S64). If execution of the third process is set (YES in step S64), processor 32 executes the third process (step S66). Specifically, if there is a peak identified as originating from multiple regions among the peaks extracted in step S46, processor 32 calculates the difference between the peak frequency of the peak and the characteristic frequency of each of the multiple regions, and prioritizes the multiple regions in order of the smallest difference. If execution of the third process is not set (NO in step S64), processor 32 proceeds to step S68 without executing the third process. Processor 32 determines the region selected as the candidate region at this time as the abnormal region.

[0089] Then, processor 32 causes display device 34 to display the vibration state determination result and abnormal part for each of the top 10 peaks in terms of peak value (step S68). Furthermore, if there is a peak for which priorities have been assigned to multiple abnormal parts as a result of executing the third process, processor 32 causes display device 34 to display the multiple parts based on the priorities.

[0090] Next, processor 32 determines whether or not the user has performed an end operation to end the measurement (step S72). If the end operation has not been performed (NO in step S72), the process returns to step S32. On the other hand, if the end operation has been performed (YES in step S72), processor 32 transitions the process to END, and the series of processes in mobile information terminal 30 ends.

[0091] As described above, in this embodiment, the validity of a possibly damaged portion identified based on a peak in the frequency spectrum of the measurement data is verified based on its relationship with other peaks in the frequency spectrum. Then, of the identified possibly damaged portions, only those portions with a high probability of being damaged are displayed on the display device 34. This allows the user to easily identify portions with a high probability of an abnormality.

[0092] Furthermore, according to this embodiment, when multiple abnormal portions are identified from one peak, the priorities of the multiple abnormal portions are determined based on the frequency of the one peak and the characteristic frequencies of each of the multiple abnormal portions. Then, the multiple abnormal portions are displayed on the display device 34 in accordance with the priorities. This allows the user to easily identify portions that are highly likely to have an abnormality.

[0093] In this embodiment, a tolerance is set, but the tolerance does not need to be set when the first process and the second process are executed without executing the third process. In this case, a peak of a frequency that coincides with a feature frequency is determined to be a peak derived from an abnormality in a part corresponding to the feature frequency.

[0094] In addition, the number of peaks to be displayed can be set by the user, allowing for a display that meets the user's wishes. Furthermore, since communication is performed wirelessly between measuring instrument 20 and mobile information terminal 30, the user can check the vibration analysis results from anywhere within the range of wireless communication, as long as measuring instrument 20 is installed at the measurement target.

[0095] In this embodiment, the control device 31 identifies the locations of the top 10 peaks in terms of peak value and causes the display device 34 to display the abnormal locations corresponding to those peaks, but the control device 31 may also identify the locations of all identified peaks, or cause the display device 34 to display the locations corresponding to all identified peaks.

[0096] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0097] 10 Abnormal part identification system, 15 Measurement object (rolling bearing), 20 Measuring instrument, 30 Portable information terminal, 31 Control device, 32 Processor, 33 Memory, 34 Display device, 35 Input device, 36 Communication device, 102 Acceleration sensor, 104 Anti-aliasing filter, 106 A / D converter, 108 Microcomputer, 110 Memory, 112 Communication module.

Claims

1. A vibration analysis device that receives measurement data from a measuring device that measures vibrations of a rotating body and identifies an abnormal part that is a part of the rotating body that may have an abnormality, A control device and a display device are provided, The control device receiving information about the rotating body; performing a frequency analysis of the measurement data; calculating, based on the information, each of the characteristic frequencies caused by an abnormality in each portion of the rotating body; determining candidate regions corresponding to each peak of the frequency spectrum obtained by the frequency analysis based on each of the characteristic frequencies; When a first peak corresponding to a characteristic frequency of a specific region is present in the frequency spectrum, if a second peak corresponding to the characteristic frequency of the specific region and having a lower order than the first peak is not present in the frequency spectrum, the specific region is excluded from the candidate regions, and the remaining candidate regions are determined to be the abnormal region; a vibration analysis device that causes the display device to display the abnormal portion for each peak of the frequency spectrum;

2. The control device further receiving a reference value for determining a vibration state of the rotating body; generating a determination result for determining a vibration state for each of the peaks in the frequency spectrum based on the peak value of each of the peaks in the frequency spectrum and the determination reference value; The vibration analysis device according to claim 1 , wherein the display device displays the peak values ​​of the peaks in the frequency spectrum and the determination results.

3. 3. The vibration analysis device according to claim 1, wherein the order of the second peak is first order.

4. 3. The vibration analysis device according to claim 1, wherein the control device further excludes the specific part from the candidate parts when the second peak is present in the frequency spectrum and the peak value of the second peak is equal to or less than the peak value of the first peak.

5. The control device further Accepting a tolerance range for each of the characteristic frequencies; 3. The vibration analysis device according to claim 1, wherein the candidate portions are determined based on whether or not the frequency of each peak in the frequency spectrum is included in the tolerance range.

6. The vibration analysis device according to claim 5 , wherein the tolerance is set by a user of the vibration analysis device.

7. The control device further When one or more regions are determined as the candidate regions for a third peak included in the frequency spectrum, a difference between each of the characteristic frequencies of the one or more regions and the frequency of the third peak is calculated; The vibration analysis device according to claim 6 , wherein the display device displays the one or more portions of the third peak in a manner based on the difference.

8. The vibration analysis device according to claim 7 , wherein the control device causes the display device to display the one or more parts in ascending order of the difference.

9. A vibration analysis device that receives measurement data from a measuring instrument that measures vibrations of a rotating body and identifies an abnormal portion that is a candidate for an abnormal portion of the rotating body, A control device and a display device are provided, The control device receiving information about the rotating body and a tolerance range for each of characteristic frequencies caused by an abnormality in each part of the rotating body, the tolerance range being calculated based on the information; performing a frequency analysis of the measurement data; calculating each of the characteristic frequencies; determining the abnormal portion based on whether or not each frequency of a peak in the frequency spectrum obtained by the frequency analysis is included in the tolerance range; When one or more regions are determined as the abnormal region for a fourth peak included in the frequency spectrum, a difference between each of the characteristic frequencies of the one or more regions and the frequency of the fourth peak is calculated; a vibration analysis device that displays, on the display device, the one or more portions as the abnormal portion for the fourth peak in a manner based on the difference;

10. The vibration analysis device according to claim 9 , wherein the control device causes the display device to display the one or more parts in ascending order of the difference.

11. 10. The vibration analyzer according to claim 1, wherein the rotating body is a bearing.

12. The information about the rotating body includes: the rotational speed or frequency of the bearing; 12. The vibration analyzer according to claim 11, further comprising: specifications of the bearing, or a coefficient of the rotational frequency used to calculate a ball pass frequency of the inner ring (BPFI), a ball pass frequency of the outer ring (BPFO), and a rolling element rotational frequency (Ball Spin Frequency (BSF)) of the bearing.

13. 10. The vibration analysis device according to claim 1, further comprising a communication device that performs wireless communication with said measuring device.

14. a measuring instrument for measuring the vibration of a rotating body that is a measurement target; 10. An abnormality portion identifying system comprising: the vibration analysis device according to claim 1, which receives measurement data from the measuring instrument and performs vibration analysis.

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