Magnetic substance inspection system and magnetic substance inspection method

Abstract

To provide a magnetic substance inspection system that can easily grasp the degree of deterioration of a magnetic substance.SOLUTION: The magnetic substance inspection system 100 comprises: a magnetic substance inspection device 1 that includes a differential coil 13, and acquires a plurality of magnetic signals 30 from one wire rope W; and a processing device 2 that includes a display unit 20 and a processing unit 21. The processing unit 21 is configured to acquire the distribution of signal waveforms 31 on the basis of the plurality of magnetic signals 30 acquired by the magnetic substance inspection device 1, and cause the display unit 20 to display a deterioration index indicating the degree of deterioration of the wire rope W based on the distribution of the signal waveforms 31.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a magnetic material inspection system and a magnetic material inspection method, and particularly to a magnetic material inspection system and a magnetic material inspection method for detecting the magnetic flux of a magnetic material.

Background Art

[0002] Conventionally, a magnetic material inspection device for detecting the magnetic flux of a magnetic material has been known (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses an inspection device for a wire rope for inspecting abnormalities in a wire rope (magnetic material). The wire rope inspection device disclosed in Patent Document 1 is configured to measure leakage magnetic fluxes in the radial direction and the longitudinal direction of the wire rope. Further, the wire rope inspection device disclosed in Patent Document 1 is configured to determine the broken state of the strands of the wire rope based on the combination of the magnitudes of the measured leakage magnetic fluxes in the radial direction and the longitudinal direction.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Here, although not disclosed in the above Patent Document 1, the wire rope (magnetic material) provided in an elevator or the like is inspected based on a defined standard and replaced based on the defined standard. When the wire rope (magnetic material) provided in an elevator or the like deteriorates due to breakage, diameter reduction, wear, damage, deformation (kink, twist disorder), etc., it is necessary to replace the wire rope. That is, the replacement timing of the wire rope is determined not only by whether there is a break in the magnetic material but also by the degree of deterioration linked to the safety factor of the wire rope. However, in the wire rope (magnetic material) breakage detection device (magnetic material inspection system) as described in the above Patent Document 1, while it is possible to determine the breakage state of the strands of the wire rope, there is a disadvantage that the degree of deterioration of the wire rope cannot be determined. In this case, there is a problem that it is difficult for the operator (inspector) to grasp the degree of deterioration of the magnetic material.

[0006] This invention has been made to solve the above problems, and one object of this invention is to provide a magnetic material inspection system and a magnetic material inspection method capable of easily grasping the degree of deterioration of a magnetic material.

Means for Solving the Problems

[0007] To achieve the above object, as a result of intensive studies by the inventors of the present application, a new finding was obtained that the degree of deterioration of a magnetic material can be grasped based on the distribution of the signal waveforms based on the magnetic signals of the magnetic material. The magnetic material inspection system according to the first aspect of this invention utilizes this new finding to display a deterioration index indicating the degree of deterioration of the magnetic material. That is, the magnetic material inspection system according to the first aspect of this invention includes a magnetic material inspection device that includes a detection coil and acquires a plurality of magnetic signals from one magnetic material, a display unit, and a processing device including a processing unit. The processing unit acquires the distribution of the signal waveforms based on the plurality of magnetic signals acquired by the magnetic material inspection device, and is configured to cause the display unit to display a deterioration index indicating the degree of deterioration of the magnetic material based on the distribution of the signal waveforms.

[0008] Moreover, the magnetic body inspection method according to the second aspect of the present invention includes a step of acquiring a plurality of magnetic signals from a magnetic body, a step of acquiring a distribution of signal waveforms based on the plurality of magnetic signals based on the plurality of magnetic signals, and a step of displaying a degradation index indicating the degree of degradation of the magnetic body based on the distribution of the signal waveforms.

Advantages of the Invention

[0009] In the magnetic body inspection system according to the first aspect of the present invention and the magnetic body inspection method according to the second aspect, as described above, based on a plurality of magnetic signals acquired from the magnetic body, a distribution of waveform signals is acquired, and a degradation index indicating the degree of degradation of the magnetic body based on the acquired distribution of the signal waveforms is displayed. As a result, the operator can easily grasp the degree of degradation of the magnetic body by checking the displayed degradation index. Further, since the degradation index is displayed, even an operator with low proficiency can easily grasp the degree of degradation of the magnetic body.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments embodying the present invention will be described with reference to the drawings.

[0012] With reference to FIGS. 1 to 11, the configuration of a magnetic body inspection system 100 according to an embodiment will be described.

[0013] (Configuration of Magnetic Body Inspection System) As shown in FIG. 1, the magnetic inspection system 100 is a system for inspecting the deterioration of a wire rope W that is a magnetic object to be inspected. The magnetic inspection system 100 includes a magnetic inspection device 1 that acquires a plurality of magnetic signals 30 from one wire rope W, and a processing device 2 that displays a deterioration index, which will be described later, based on the inspection result of the wire rope W by the magnetic inspection device 1. By inspecting the wire rope W with the magnetic inspection system 100, it is possible to grasp the degree of deterioration of the wire rope W that is difficult to visually confirm. Note that the wire rope W is an example of the "magnetic object" in the claims.

[0014] The wire rope W is used, for example, in an elevator. The wire rope W is formed by a plurality of magnetic strands. Specifically, the wire rope W is formed by braiding (for example, strand braiding) a plurality of strands. The wire rope W is a magnetic object made of a long member extending along a predetermined direction. In the present embodiment, the direction in which the wire rope W extends is defined as the X direction. Of the X direction, one direction is the X1 direction and the other direction is the X2 direction. Also, the direction orthogonal to the Y direction is defined as the Y direction. Of the Y direction, one direction is the Y1 direction and the other direction is the Y2 direction.

[0015] The wire rope W is monitored by the magnetic inspection device 1 in order to prevent a rope breakage accident due to deterioration. As a result of measuring the magnetic flux, if it is determined that the degree of deterioration has exceeded a determined standard, the wire rope W is replaced by an operator. Note that the deterioration of the wire rope W includes a state in which, in addition to the disconnection of the strands of the wire rope W, disconnection, diameter reduction, wear, damage, deformation (kink, twist disorder), etc. have occurred.

[0016] The magnetic inspection device 1 acquires a magnetic signal 30 by measuring the magnetic flux of the wire rope W while relatively moving in the longitudinal direction (X direction) of the wire rope W along the surface of the wire rope W. For example, when the wire rope W itself moves, such as a wire rope W used in an elevator, while the magnetic inspection device 1 is fixed to the wire rope W, the magnetic flux of the wire rope W is measured by the magnetic inspection device 1 while the wire rope W is moved in the X direction. In the present embodiment, the magnetic inspection device 1 is configured to acquire magnetic signals 30 at a plurality of measurement positions of up to 100,000 to 1,000,000 or more (measurement pitch of 1 mm to 0.1 mm or less) with respect to one wire rope W.

[0017] Also, as shown in FIG. 1, the processing device 2 includes a display unit 20, a processing unit 21, a communication unit 22, and a storage unit 23.

[0018] The display unit 20 is configured to display information such as the measurement result of the wire rope W and the analysis result of the measurement result of the wire rope W by the processing unit 21. Also, in the present embodiment, the display unit 20 is configured to display a deterioration index described later. The display unit 20 includes, for example, a display device such as a liquid crystal monitor or an organic EL (Electro Luminescence) monitor.

[0019] The processing unit 21 controls each part of the processing device 2. The processing unit 21 includes a processor or circuitry such as a CPU (Central Processing Unit), and a memory. The processing unit 21 analyzes the deterioration of the wire rope W such as strand breakage based on the magnetic signal 30 of the wire rope W received via the communication unit 22. In the present embodiment, the processing unit 21 acquires a deterioration index indicating the degree of deterioration of the wire rope W based on a plurality of magnetic signals 30 acquired by the magnetic inspection device 1. Details of the configuration in which the processing unit 21 acquires the deterioration index will be described later.

[0020] The communication unit 22 is configured to communicably connect the magnetic inspection device 1 and the processing device 2. The communication unit 22 is, for example, an interface for communication.

[0021] The storage unit 23 is configured to store (save) information such as the measurement result of the wire rope W and the analysis result of the measurement result of the wire rope W by the processing unit 21. In the present embodiment, the storage unit 23 is configured to store the threshold value 40 or the reference value 41 used when obtaining the degree of deterioration of the wire rope W. Further, in the present embodiment, the storage unit 23 is configured to store a deterioration index. In the present embodiment, the deterioration index includes the standard deviation 50 or the variance 51. The storage unit 23 is, for example, a storage medium including a flash memory.

[0022] Note that when the threshold value 40 is used to obtain the degree of deterioration of the wire rope W, the storage unit 23 does not have to store the reference value 41. Further, when the reference value 41 is used to obtain the degree of deterioration of the wire rope W, the storage unit 23 does not have to store the threshold value 40. Further, when the processing unit 21 obtains the standard deviation 50 as the deterioration index, the storage unit 23 does not have to store the variance 51. Further, when the processing unit 21 obtains the variance 51 as the deterioration index, the storage unit 23 does not have to store the standard deviation 50.

[0023] (Magnetic Inspection Device) As shown in FIG. 2, the magnetic inspection device 1 includes an electronic circuit unit 10, a detection unit 11, and a magnetic field application unit 14.

[0024] The electronic circuit unit 10 is configured to control each part of the magnetic inspection device 1. The electronic circuit unit 10 includes a processor or circuitry such as a CPU, a memory, and an AD converter. Further, the electronic circuit unit 10 includes a communication interface for communicably connecting the magnetic inspection device 1 and the processing device 2.

[0025] The detection unit 11 detects (measures) the magnetic flux of the wire rope W in a non-contact state. Specifically, the detection unit 11 includes an excitation coil 12 and a differential coil 13. The differential coil 13 is an example of the "detection coil" in the claims.

[0026] The excitation coil 12 excites the magnetization state of the wire rope W. The excitation coil 12 is composed of a conducting wire and is arranged around the axis of the wire rope W so as to surround the wire rope W. When an alternating excitation current flows through the excitation coil 12, a magnetic field along the X direction (the longitudinal direction and the axial direction of the wire rope W) is generated inside (inside the loop), and the generated magnetic field is applied to the wire rope W arranged inside.

[0027] The differential coil 13 has a pair of receiving coils 13a and 13b. The differential coil 13 (the receiving coils 13a and 13b) detects (measures) the magnetic flux in the X direction of the wire rope W to which a magnetic field is applied by the excitation coil 12. The receiving coils 13a and 13b of the differential coil 13 are each composed of a conducting wire and are differentially connected to each other. The receiving coils 13a and 13b of the differential coil 13 are arranged around the axis of the wire rope W so as to surround the wire rope W. The receiving coils 13a and 13b of the differential coil 13 detect the magnetic flux (total magnetic flux) in the X direction inside the wire rope W arranged inside while being relatively moved in the X direction with respect to the wire rope W. That is, the magnetic inspection system 100 according to the present embodiment is configured to inspect the wire rope W by the total magnetic flux method.

[0028] The differential coil 13 transmits a differential signal (detection signal) as a voltage in response to the magnetic flux of the detected wire rope W in the X direction. The differential signal is a signal indicating the difference between the signal from the receiving coil 13a and the signal from the receiving coil 13b. When both the receiving coil 13a and the receiving coil 13b of the differential coil 13 are located at normal positions (non-damaged positions) of the wire rope W, the differential coil 13 transmits a differential signal having a substantially zero value. This is because at normal positions of the wire rope W, the total magnetic flux of the wire rope W (the value obtained by multiplying the magnitude of the magnetic field by the permeability and the area) is substantially the same. Also, for example, when one of the receiving coil 13a and the receiving coil 13b of the differential coil 13 is located at a damaged position of the wire rope W and the other is located at a normal position of the wire rope W, the differential coil 13 transmits a differential signal (magnetic signal 30) having a relatively large value (a varying value). This is because at the damaged position of the wire rope W, the total magnetic flux is different from that at the normal position of the wire rope W.

[0029] Also, in the differential coil 13, noise can be canceled by taking the difference between the signals of the receiving coil 13a and the receiving coil 13b, so it is possible to obtain a signal with a good S / N ratio. The magnetic inspection device 1 detects (measures) the magnetic flux of the wire rope W with the differential coil 13 of the detection unit 11 while relatively moving the differential coil 13 of the detection unit 11 in the X direction with respect to the wire rope W, and acquires the magnetic signal 30.

[0030] Also, the differential coil 13 is provided inside the excitation coil 12 (inside the ring). Note that the differential coil 13 may be provided outside the excitation coil 12 (outside the ring). The receiving coil 13a and the receiving coil 13b of the differential coil 13 are arranged along the X direction in this order from the X1 direction side toward the X2 direction side.

[0031] The magnetic field application unit 14 is configured to adjust the magnitude and direction of the magnetization of the wire rope W in advance before the detection unit 11 detects the magnetic flux of the wire rope W. Thereby, it is possible to suppress the occurrence of noise due to magnetization disturbance when the detection unit 11 detects the magnetic flux of the wire rope W. In addition, it is possible to remove in advance the magnetic flux change caused by components that do not involve plastic deformation (such as magnetization and slight bending). The magnetic field application unit 14 includes magnets 14a and 14b. The magnetic field application unit 14 (magnets 14a and 14b) is arranged upstream of the detection unit 11 in the moving direction of the wire rope W. In the example shown in FIG. 2, the magnetic field application unit 14 is arranged on the X1 direction side (one side in the longitudinal direction of the wire rope W) with respect to the detection unit 11. Note that the magnetic field application unit 14 may be provided on both sides in the X direction with respect to the detection unit 11.

[0032] In addition, the magnets 14a and 14b are arranged along the Y direction. In the example shown in FIG. 2, the magnet 14a is arranged on the Y1 direction side of the wire rope W. Also, the magnet 14b is arranged on the Y2 direction side of the wire rope W. Further, in the example shown in FIG. 2, the magnets 14a and 14b are arranged such that the same poles face each other. Specifically, the magnets 14a and 14b are arranged such that the N poles face each other. Note that the magnets 14a and 14b may be arranged such that the S poles face each other. Also, the magnets 14a and 14b may be arranged such that different poles face each other.

[0033] In FIGS. 1 and 2, for the sake of convenience, one wire rope W is illustrated, but the magnetic body inspection device 1 is configured to be able to simultaneously measure a plurality of wire ropes W by including differential coils 13 corresponding to the number of wire ropes W.

[0034] (Signal waveform and frequency distribution) Next, with reference to FIGS. 3 and 4, a configuration in which the processing unit 21 (see FIG. 1) obtains a degradation index indicating the degree of degradation of the wire rope W (see FIG. 1) will be described.

[0035] The processing unit 21 acquires the distribution of the signal waveform 31 based on a plurality of magnetic signals 30 (see FIG. 1) acquired by the magnetic body inspection device 1 (see FIG. 1). The waveform shown in FIG. 3 is the signal waveform 31 acquired by the processing unit 21. The signal waveform 31 can be represented by a graph with the calculated value on the vertical axis and time on the horizontal axis.

[0036] In the present embodiment, the processing unit 21 is configured to perform preprocessing for reducing noise on the plurality of magnetic signals 30. Specifically, the processing unit 21 is configured to perform a moving average process on the plurality of magnetic signals 30 as preprocessing. Note that the processing unit 21 performs a backward moving average process as the moving average process. Then, the processing unit 21 is configured to acquire the signal waveform 31 based on the plurality of magnetic signals 30 after the preprocessing.

[0037] Also, in the present embodiment, the processing unit 21 is configured to acquire the signal waveform 31 based on the magnetic change rate of the wire rope W acquired based on the plurality of magnetic signals 30. Specifically, the processing unit 21 is configured to acquire the signal waveform 31 based on the slopes of the intensities of the magnetic signals 30 at the start point and the end point of a section set by a predetermined number of signals. In other words, the processing unit 21 is configured to acquire the signal waveform 31 based on the calculated value obtained by subtracting the signal intensity at the start point from the signal intensity at the end point of a section set by a predetermined number of signals. The processing unit 21 acquires the signal waveform 31 by acquiring the slope of the intensity while moving the section for the plurality of magnetic signals 30.

[0038] In the present embodiment, after performing a moving average process on the plurality of magnetic signals 30, the processing unit 21 is configured to acquire the signal waveform 31 based on the calculated value obtained by subtracting the signal intensity at the start point from the signal intensity at the end point of a section set by a predetermined number of signals.

[0039] Also, in the present embodiment, the processing unit 21 is configured to acquire a deterioration index indicating the degree of deterioration of the wire rope W based on the distribution of the signal waveform 31.

[0040] Specifically, as shown in FIG. 4, the processing unit 21 (see FIG. 1) is configured to obtain a frequency distribution 32 of signal intensities acquired at a plurality of measurement positions based on the signal waveform 31 (see FIG. 3), and obtain a degradation index based on the acquired frequency distribution 32. That is, the frequency distribution 32 is the distribution of the signal waveform 31.

[0041] The frequency distribution 32 is obtained based on the number of each calculated value in the signal waveform 31 shown in FIG. 3. In other words, the frequency distribution 32 is a distribution representing the frequency of the calculated values of the signal waveform 31.

[0042] Also, as shown in FIG. 4, the frequency distribution 32 has a shape that can be regarded as a so-called normal distribution. Since the frequency distribution 32 obtained based on 100,000 to 1,000,000 or more magnetic signals 30 (see FIG. 1) has a shape that can be regarded as a so-called normal distribution, the index obtained by statistically processing the frequency distribution 32 is considered to be a reliable value. Further, the value of the magnetic signal 30 increases at the location where the wire rope W is deteriorated. Therefore, the calculated value of the signal waveform 31 obtained based on the magnetic signal 30 also increases at the location where the wire rope W is deteriorated. Based on these, the inventors of the present application have obtained the finding that an index of the deterioration of the wire rope W can be obtained by performing statistical processing on the frequency distribution 32.

[0043] Therefore, based on the above findings, the processing unit 21 according to this embodiment is configured to obtain a deterioration index based on the shape of the frequency distribution 32. Specifically, the processing unit 21 is configured to obtain, as a deterioration index based on the shape of the frequency distribution 32, the standard deviation 50 or the variance 51 of the frequency distribution 32. In this embodiment, the processing unit 21 is configured to obtain the standard deviation 50 as the deterioration index. In the example shown in FIG. 4, the frequency distribution 32 has a standard deviation 50 of "25". In the following, the configuration in which the processing unit 21 obtains and displays the standard deviation 50 as the deterioration index will be described. However, the processing unit 21 may be configured to obtain and display the variance 51 as the deterioration index. The processing unit 21 obtains the standard deviation 50 or the variance 51 by a known configuration.

[0044] Next, with reference to FIGS. 5 to 11, the signal waveforms 31 and frequency distributions 32 obtained based on the magnetic signals 30 (see FIG. 1) of a plurality of wire ropes W (see FIG. 1) provided in different elevators will be described. In the example shown below, the signal waveforms 31 and frequency distributions 32 obtained based on the magnetic signals 30 of the four wire ropes W provided in each of the three elevators, i.e., the first elevator, the second elevator, and the third elevator, will be described.

[0045] (Signal Waveform and Frequency Distribution in the First Elevator) The examples shown in FIGS. 5 and 6 show the signal waveforms 31a to 31d and the frequency distributions 32a to 32d of the four wire ropes W (see FIG. 1), No. 1 to No. 4, provided in the first elevator. Each wire rope W provided in the first elevator has a length of about 100 m.

[0046] The processing unit 21 (see FIG. 1) acquires signal waveforms 31a to 31d shown in FIG. 5 based on the magnetic signals 30 (see FIG. 1) acquired from each of the four wire ropes W provided in the first elevator. Then, the processing unit 21 acquires frequency distributions 32a to 32d shown in FIG. 6 from the signal waveforms 31a to 31d shown in FIG. 5, respectively. The configuration in which the processing unit 21 acquires the signal waveforms 31a to 31d is the same as the configuration in which the processing unit 21 acquires the signal waveform 31 shown in FIG. 3. Also, the configuration in which the processing unit 21 acquires the frequency distributions 32a to 32d is the same as the configuration in which the processing unit 21 acquires the frequency distribution 32 shown in FIG. 4.

[0047] As shown in FIG. 6, for the frequency distribution 32a, the standard deviation 50a is "25". Also, for the frequency distribution 32b, the standard deviation 50b is "24". Also, for the frequency distribution 32c, the standard deviation 50c is "23". Also, for the frequency distribution 32d, the standard deviation 50d is "28".

[0048] (Signal waveforms and frequency distributions in the second elevator) The examples shown in FIGS. 7 and 8 show the signal waveforms 31e to 31h and the frequency distributions 32e to 32h of the four wire ropes W numbered 1 to 4 (see FIG. 1) provided in the second elevator. Each wire rope W provided in the second elevator has a length of approximately 200 m.

[0049] The processing unit 21 (see FIG. 1) acquires the signal waveforms 31e to 31h shown in FIG. 7 based on the magnetic signals 30 (see FIG. 1) acquired from each of the four wire ropes W provided in the second elevator. Then, the processing unit 21 acquires the frequency distributions 32e to 32h shown in FIG. 8 from the signal waveforms 31e to 31h shown in FIG. 7, respectively.

[0050] As shown in FIG. 8, for the frequency distribution 32e, the standard deviation 50e is "34". Also, for the frequency distribution 32f, the standard deviation 50f is "33". Also, for the frequency distribution 32g, the standard deviation 50g is "31". Also, for the frequency distribution 32h, the standard deviation 50h is "36".

[0051] (Signal Waveform and Frequency Distribution in the Third Elevator) The examples shown in FIGS. 9 and 10 show the signal waveforms 31i to 31l and the frequency distributions 32i to 32l of the four wire ropes W (see FIG. 1) numbered 1 to 4 provided in the third elevator. Each wire rope W provided in the third elevator has a length of about 300 m.

[0052] The processing unit 21 acquires the signal waveforms 31i to 31l shown in FIG. 9 based on the magnetic signals 30 (see FIG. 1) acquired from each of the four wire ropes W provided in the third elevator. Then, the processing unit 21 acquires the frequency distributions 32i to 32l shown in FIG. 10 from the signal waveforms 31i to 31l shown in FIG. 9, respectively.

[0053] As shown in FIG. 10, for the frequency distribution 32i, the standard deviation 50i is "40". Also, for the frequency distribution 32j, the standard deviation 50j is "36". Also, for the frequency distribution 32k, the standard deviation 50k is "35". Also, for the frequency distribution 32l, the standard deviation 50l is "35".

[0054] When the operator (inspector) inspected each of the wire ropes W of the first to third elevators, a broken strand was detected in the No. 1 wire rope W of the third elevator. That is, in the present embodiment, the deterioration index is configured such that the larger the value of the standard deviation 50 or the variance 51, the more the deterioration of the wire rope W has progressed.

[0055] (Display of Frequency Distribution and Deterioration Index) As shown in FIG. 11, the processing unit 21 (see FIG. 1) is configured to cause the display unit 20 (see FIG. 1) to display the deterioration index. The screen 20a shown in FIG. 11 is an example of a screen when the processing unit 21 displays the deterioration index on the display unit 20. In the present embodiment, the processing unit 21 is configured to cause the display unit 20 to display at least one of the deterioration index and the frequency distribution 32. In the example shown in FIG. 11, the processing unit 21 displays both the standard deviation 50 (standard deviations 50a to 50l) which is the deterioration index and the frequency distribution 32 (frequency distributions 32a to 32l).

[0056] Here, when the standard deviation 50 is displayed as the deterioration index, a numerical value corresponding to the degree of deterioration of the wire rope W is displayed. However, in the case of an operator with low proficiency, it may be difficult to easily grasp the relationship between the numerical value of the standard deviation 50 and the degree of deterioration of the wire rope W at a glance.

[0057] Therefore, in the present embodiment, the processing unit 21 compares the deterioration index consisting of the standard deviation 50 or the variance 51 (see FIG. 1) with a preset threshold value 40 (see FIG. 1), and when the deterioration index is equal to or greater than the threshold value 40, it is configured to cause the display unit 20 to display that the degree of deterioration of the wire rope W is large. Specifically, when the standard deviation 50 is equal to or greater than the threshold value 40, the processing unit 21 is configured to display a message 60 indicating that the degree of deterioration of the wire rope W is large, together with the frequency distribution 32 and the standard deviation 50. Note that the threshold value 40 can be changed according to the type of the wire rope W, the type of the elevator, etc. The threshold value 40 is experimentally obtained and stored in the storage unit 23 in advance.

[0058] Note that the processing unit 21 may be configured to obtain the ratio between the deterioration index consisting of the standard deviation 50 or the variance 51 and the reference value 41 acquired in advance, and cause the display unit 20 to display that the degree of deterioration of the wire rope W is large when the acquired ratio is equal to or greater than a predetermined value. The reference value 41 is a deterioration index acquired based on a plurality of magnetic signals 30 measured when the wire rope W was installed. Note that if the predetermined value is too small, even for a wire rope W that does not need to be replaced, it will be determined that the degree of deterioration is large. Also, if the predetermined value is too large, it will be impossible to determine that the degree of deterioration is large for a wire rope W that has already deteriorated to the extent that replacement is necessary. Therefore, the predetermined value is preferably set to, for example, about 1.3 to about 2.0. More preferably, the predetermined value is about 1.4 to about 1.8. Even more preferably, the predetermined value is about 1.5 to about 1.6. For example, when the predetermined value is 1.5 and the ratio between the deterioration index and the reference value 41 of each frequency distribution 32 shown in FIGS. 6, 8, and 10 is obtained, only the frequency distribution 32i exceeds the predetermined value (1.5). When the inspector visually inspected the wire rope W No. 1 of the third elevator from which the frequency distribution 32i was obtained, a broken wire was confirmed in the wire rope W. Note that the predetermined value can be changed according to the type of the wire rope W, the type of the elevator, and the like.

[0059] (Inspection method for wire rope) Next, with reference to FIG. 12, the process in which the processing unit 21 (see FIG. 1) inspects the wire rope W (see FIG. 1) will be described.

[0060] In step 110, the processing unit 21 obtains a plurality of magnetic signals 30 (see FIG. 1) from the wire rope W. In the present embodiment, the processing unit 21 obtains a plurality of magnetic signals 30 from each of the four wire ropes W.

[0061] In step 111, the processing unit 21 obtains the distribution of the signal waveform 31 (see FIG. 3) based on the plurality of magnetic signals 30. In the present embodiment, in step 111, after performing a moving average process on the plurality of magnetic signals 30, the processing unit 21 obtains the signal waveform 31 based on the calculated value obtained by subtracting the signal intensity at the start point from the signal intensity at the end point of the section set by the predetermined number of signals. Then, the processing unit 21 obtains the frequency distribution 32 (see FIG. 4) from the obtained signal waveform 31.

[0062] In step 112, the processing unit 21 obtains a deterioration index. Specifically, the processing unit 21 obtains the standard deviation 50 (see FIG. 4) of the frequency distribution 32 obtained in step 111 as the deterioration index.

[0063] In step 113, the processing unit 21 obtains the threshold value 40 (see FIG. 1) or the reference value 41 (see FIG. 1) from the storage unit 23 (see FIG. 1).

[0064] In step 114, the processing unit 21 determines whether the degree of deterioration of the wire rope W is large. Specifically, the processing unit 21 determines whether the degree of deterioration of the wire rope W is large based on the standard deviation 50 obtained in step 112 and the threshold value 40 or the reference value 41 obtained in step 113.

[0065] When using the threshold value 40, the processing unit 21 compares the standard deviation 50 with the threshold value 40, and determines that the degree of deterioration of the wire rope W is large when the standard deviation 50 is greater than or equal to the threshold value 40. Also, the processing unit 21 determines that the degree of deterioration of the wire rope W is small when the standard deviation 50 is less than the threshold value 40.

[0066] Also, when using the reference value 41, the processing unit 21 obtains the ratio of the standard deviation 50 to the reference value 41, and if the obtained ratio is equal to or greater than a predetermined value, it determines that the degree of deterioration of the wire rope W is large. Further, when the ratio of the standard deviation 50 to the reference value 41 is less than the predetermined value, the processing unit 21 determines that the degree of deterioration of the wire rope W is small.

[0067] When the processing unit 21 determines that the degree of deterioration of the wire rope W is large, the process proceeds to step 115. Also, when the processing unit 21 determines that the degree of deterioration of the wire rope W is small, the process proceeds to step 116.

[0068] In step 115, the processing unit 21 causes the display unit 20 (see FIG. 1) to display the frequency distribution 32, the standard deviation 50 which is a deterioration index, and a message 60 (see FIG. 11) indicating that the degree of deterioration of the wire rope W is large. Thereafter, the process proceeds to step 117.

[0069] Also, when the process proceeds from step 114 to step 116, in step 116, the processing unit 21 causes the display unit 20 to display the frequency distribution 32 and the standard deviation 50 which is a deterioration index. Thereafter, the process proceeds to step 117.

[0070] In step 117, the processing unit 21 determines whether or not the deterioration index has been obtained for all the wire ropes W. In the present embodiment, the processing unit 21 determines whether or not the standard deviation 50 has been obtained for all the wire ropes W. If the standard deviation 50 has not been obtained for all the wire ropes W, the process proceeds to step 110. If the standard deviation 50 of all the wire ropes W has been obtained, the process ends.

[0071] In the present embodiment, as described above, in both step 115 and step 116, the processing unit 21 displays a deterioration index indicating the degree of deterioration of the wire rope W based on the distribution of the signal waveform 31.

[0072] (Effect of this embodiment) In this embodiment, the following effects can be obtained.

[0073] In this embodiment, as described above, the magnetic inspection system 100 includes a differential coil 13, a magnetic inspection device 1 that acquires a plurality of magnetic signals 30 from the wire rope W, a display unit 20, and a processing device 2 that includes a processing unit 21. The processing unit 21 is configured to acquire the distribution of the signal waveform 31 based on the plurality of magnetic signals 30 acquired by the magnetic inspection device 1, and cause the display unit 20 to display a deterioration index indicating the degree of deterioration of the wire rope W based on the distribution of the signal waveform 31.

[0074] As a result, since the deterioration index is displayed on the display unit 20, the operator can easily grasp the degree of deterioration of the wire rope W by checking the deterioration index. Further, since the deterioration index is displayed, even an operator with low proficiency can easily grasp the degree of deterioration of the wire rope W.

[0075] Further, in this embodiment, as described above, the magnetic inspection method includes a step of acquiring a plurality of magnetic signals 30 from the wire rope W, a step of acquiring the distribution of the signal waveform 31 based on the plurality of magnetic signals 30, and a step of displaying a deterioration index indicating the degree of deterioration of the wire rope W based on the distribution of the signal waveform 31.

[0076] As a result, similar to the magnetic inspection system 100, a magnetic inspection method capable of easily grasping the degree of deterioration of the magnetic material can be provided.

[0077] Further, in the above embodiment, by configuring as follows, the following further effects can be obtained.

[0078] That is, in the present embodiment, as described above, the processing unit 21 is configured to obtain the frequency distribution 32 of the signal intensities acquired at a plurality of measurement positions based on the signal waveform 31, and obtain a degradation index based on the obtained frequency distribution 32. Thereby, by obtaining the frequency distribution 32, the degradation index can be obtained without performing complicated processing.

[0079] Also, in the present embodiment, as described above, the processing unit 21 is configured to obtain a degradation index based on the shape of the frequency distribution 32. Here, as a result of intensive studies by the inventors of the present application, it was found that the shape of the frequency distribution 32 changes according to the degree of degradation of the magnetic material (wire rope W). Based on this finding, it has been found that the degradation index of the wire rope W can be easily obtained by obtaining the degradation index based on the shape of the frequency distribution 32.

[0080] Also, in the present embodiment, as described above, the processing unit 21 is configured to obtain the standard deviation 50 or the variance 51 of the frequency distribution 32 as a degradation index based on the shape of the frequency distribution 32. Thereby, the standard deviation 50 or the variance 51 of the frequency distribution 32 can be displayed as a degradation index. As a result, the operator can quantitatively grasp the degree of degradation of the magnetic material based on the standard deviation 50 or the variance 51 of the frequency distribution 32.

[0081] Also, in the present embodiment, as described above, the degradation index is configured such that the greater the value of the standard deviation 50 or the variance 51, the more advanced the degradation of the magnetic material (wire rope W). Thereby, the operator can easily grasp the progress of the degradation of the wire rope W based on the value of the standard deviation 50 or the variance 51.

[0082] Also, in the present embodiment, as described above, the processing unit 21 is configured to cause the display unit 20 to display at least one of the deterioration index and the frequency distribution 32. Thereby, when the deterioration index is displayed on the display unit 20, the operator can quantitatively grasp the degree of deterioration of the magnetic body (wire rope W) based on the deterioration index. Further, when the frequency distribution 32 is displayed on the display unit 20, the operator can intuitively grasp the degree of deterioration of the wire rope W based on the shape of the frequency distribution 32. As a result, it becomes possible for the operator to quantitatively or intuitively grasp the degree of deterioration of the wire rope W, so that the convenience (usability) of the operator can be improved.

[0083] Also, in the present embodiment, as described above, the processing unit 21 is configured to acquire the signal waveform 31 based on the magnetic change rate of the magnetic body (wire rope W) acquired based on the plurality of magnetic signals 30. Here, at the location where the wire rope W is deteriorated, the magnetic change of the wire rope W becomes larger compared to the non-deteriorated location. Therefore, by configuring as described above, since the signal waveform 31 is acquired based on the magnetic change rate of the wire rope W, the peak magnitude can be made prominent according to the degree of deterioration of the wire rope W in the signal waveform 31. That is, among the signal waveforms 31, the calculated value of the peak at the deteriorated location becomes larger, and the peak of the calculated value at the non-deteriorated location becomes smaller. As a result, since the deterioration index is acquired based on the signal waveform 31 having a peak with a magnitude made prominent according to the degree of deterioration, compared with the configuration of acquiring the deterioration index based on the magnetic signal 30, a deterioration index that more reflects the degree of deterioration can be acquired.

[0084] Also, in the present embodiment, as described above, the processing unit 21 performs preprocessing for reducing noise on a plurality of magnetic signals 30, and is configured to acquire a signal waveform 31 based on the plurality of magnetic signals 30 after the preprocessing. Thereby, the noise included in the signal waveform 31 can be reduced. As a result, since it becomes possible to acquire a deterioration index based on the signal waveform 31 with reduced noise, it is possible to suppress a decrease in the accuracy of the deterioration index.

[0085] Also, in the present embodiment, as described above, the processing unit 21 compares a deterioration index composed of a standard deviation 50 or a variance 51 with a preset threshold value 40, and when the deterioration index is equal to or greater than the threshold value 40, the processing unit 21 is configured to cause the display unit 20 to display that the degree of deterioration of the magnetic body (wire rope W) is large. Thereby, when the standard deviation 50 or the variance 51 is equal to or greater than the threshold value 40, the display unit 20 displays that the degree of deterioration of the wire rope W is large. Therefore, the operator can easily determine the degree of deterioration of the magnetic body.

[0086] Also, in the present embodiment, as described above, the processing unit 21 acquires a ratio of a deterioration index composed of a standard deviation 50 or a variance 51 to a reference value 41 acquired in advance, and when the acquired ratio is equal to or greater than a predetermined value, the processing unit 21 is configured to cause the display unit 20 to display that the degree of deterioration of the magnetic body (wire rope W) is large. Thereby, when the ratio of the standard deviation 50 or the variance 51 to the reference value 41 is equal to or greater than the predetermined value, the display unit 20 displays that the degree of deterioration of the wire rope W is large. Therefore, it is possible to provide a magnetic body inspection system 100 that enables the operator to easily determine the degree of deterioration of the magnetic body.

[0087] Also, in the present embodiment, as described above, the reference value 41 is a deterioration index obtained based on a plurality of magnetic signals 30 measured when the magnetic body (wire rope W) is installed. As a result, individual reference values 41 are set for each wire rope W, so that the processing unit 21 can determine whether the degree of deterioration of the wire rope W is large based on the degree of progress of deterioration for each wire rope W. As a result, compared with a configuration in which it is determined whether the degree of deterioration of the wire rope W is large based on a common reference value 41 for a plurality of wire ropes W, it is possible to more accurately determine whether the degree of deterioration of the wire rope W is large.

[0088] [Modification Example] It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is shown not by the description of the above-described embodiments but by the claims, and further includes all changes (modification examples) within the meaning and scope equivalent to the claims.

[0089] For example, in the above embodiment, an example of a configuration in which the processing unit 21 acquires the standard deviation 50 of the frequency distribution 32 as a deterioration index has been shown, but the present invention is not limited to this. For example, the processing unit may be configured to normalize the frequency distribution 32 by the number of signals and acquire the height (or low) of the normalized frequency distribution as a deterioration index. Further, the processing unit may be configured to acquire the spread of the normalized frequency distribution as a deterioration index.

[0090] Also, in the above embodiment, an example of a configuration in which the processing unit 21 displays both the standard deviation 50, which is a deterioration index, and the frequency distribution 32 on the display unit 20 has been shown, but the present invention is not limited to this. For example, the processing unit may be configured to display only one of the standard deviation 50, which is a deterioration index, and the frequency distribution 32 on the display unit 20.

[0091] In the above-described embodiment, an example of the configuration in which the processing unit 21 obtains the signal waveform 31 based on the magnetic change rate of the wire rope W obtained based on a plurality of magnetic signals 30 has been shown. However, the present invention is not limited to this. For example, the processing unit may be configured to obtain a plurality of magnetic signals 30 as they are as the signal waveform. However, when the processing unit 21 obtains a plurality of magnetic signals 30 as they are as the signal waveform, the magnitude of the peak cannot be emphasized according to the degree of deterioration of the wire rope W in the signal waveform. Therefore, it is preferable that the processing unit 21 is configured to obtain the signal waveform 31 based on the magnetic change rate of the wire rope W obtained based on a plurality of magnetic signals 30.

[0092] In the above-described embodiment, an example of the configuration in which the processing unit 21 obtains the signal waveform 31 by subtracting the calculated value of the start point from the calculated value of the end point of the section set by a predetermined number of signals for a plurality of magnetic signals 30 has been shown. However, the present invention is not limited to this. For example, the processing unit may be configured to obtain, as the signal waveform, the calculated value obtained by subtracting the calculated value of the start point from the calculated value of the end point of the section set by a predetermined number of signals for the calculated value of the signal waveform 31. That is, the processing unit may be configured to obtain the signal waveform by performing the process of subtracting the calculated value of the start point from the calculated value of the end point of the section set by a predetermined number of signals for a plurality of magnetic signals 30 twice. Further, the processing unit may be configured to obtain the signal waveform 31 by performing a differentiation process on a plurality of magnetic signals 30.

[0093] In the above-described embodiment, an example of the configuration in which the processing unit 21 performs preprocessing for reducing noise with respect to a plurality of magnetic signals 30 has been shown. However, the present invention is not limited to this. For example, the processing unit may not perform preprocessing for reducing noise with respect to the plurality of magnetic signals 30. However, when the processing unit 21 does not perform preprocessing for reducing noise with respect to the plurality of magnetic signals 30, since the frequency distribution 32 is obtained based on the signal waveform 31 including noise, the accuracy of the degradation index decreases. Therefore, it is preferable that the processing unit 21 is configured to perform preprocessing for reducing noise with respect to the plurality of magnetic signals 30.

[0094] In the above-described embodiment, an example of the configuration in which the processing unit 21 obtains the signal waveform 31 based on the calculated value obtained by subtracting the signal intensity at the start point from the signal intensity at the end point of the section set by a predetermined number of signals after performing the moving average process on the plurality of magnetic signals 30 has been shown. However, the present invention is not limited to this. For example, the processing unit 21 may be configured to perform either one of the moving average process and the process of subtracting the signal intensity at the start point from the signal intensity at the end point of the section set by a predetermined number of signals. However, from the viewpoint of the accuracy of the degradation index, it is preferable that the processing unit 21 is configured to obtain the signal waveform 31 based on the calculated value obtained by subtracting the signal intensity at the start point from the signal intensity at the end point of the section set by a predetermined number of signals after performing the moving average process on the plurality of magnetic signals 30.

[0095] In the above-described embodiment, an example of the configuration in which the reference value 41 is a degradation index obtained based on a plurality of magnetic signals 30 measured when the wire rope W is installed has been shown. However, the present invention is not limited to this. For example, the reference value may be a degradation index obtained based on a plurality of magnetic signals 30 measured when the wire rope W is manufactured.

[0096] In the above-described embodiment, an example of the configuration in which the processing unit 21 acquires the standard deviation 50 or the variance 51 as a deterioration index and displays it on the display unit 20 has been shown. However, the present invention is not limited to this. For example, the processing unit may be configured to acquire the frequency distribution 32 as a deterioration index and display it on the display unit 20. That is, the frequency distribution 32 can be used as a deterioration index of the wire rope W.

[0097] In the above-described embodiment, an example of the configuration in which the processing unit 21 displays the frequency distribution 32 and the standard deviation 50 for each of the wire ropes W provided in the first to third elevators has been shown. However, the present invention is not limited to this. For example, the processing unit may be configured to display the frequency distribution 32 and the standard deviation 50 for the wire rope W provided in one elevator. That is, the processing unit may be configured to display the frequency distribution 32 and the standard deviation 50 only for the wire rope W provided in the elevator to be inspected.

[0098] In the above-described embodiment, an example of the configuration in which the magnetic body inspection system 100 inspects the wire rope (magnetic body) provided in the elevator has been shown. However, the present invention is not limited to this. In the present invention, the magnetic body inspection system may be used for inspecting wire ropes provided other than elevators, such as cranes, suspension bridges, and robots.

[0099] [Aspect] Those skilled in the art will understand that the above-exemplified embodiments are specific examples of the following aspects.

[0100] (Item 1) A magnetic body inspection device including a differential coil and acquiring a plurality of magnetic signals from one magnetic body, A processing device including a display unit and a processing unit, The processing unit is configured to acquire a distribution of signal waveforms based on the plurality of magnetic signals acquired by the magnetic body inspection device, and cause the display unit to display a deterioration index indicating the degree of deterioration of the magnetic body based on the distribution of the signal waveforms. A magnetic body inspection system.

[0101] (Item 2) The processing unit is configured to obtain a frequency distribution of signal intensities acquired at a plurality of measurement positions based on the signal waveform, and obtain the deterioration index based on the obtained frequency distribution. The magnetic inspection system according to Item 1

[0102] (Item 3) The processing unit is configured to obtain the deterioration index based on the shape of the frequency distribution. The magnetic inspection system according to Item 2

[0103] (Item 4) The processing unit is configured to obtain, as the deterioration index based on the shape of the frequency distribution, the standard deviation or variance of the frequency distribution. The magnetic inspection system according to Item 3

[0104] (Item 5) The deterioration index is configured such that the larger the value of the standard deviation or the variance, the more advanced the deterioration of the magnetic material. The magnetic inspection system according to Item 4

[0105] (Item 6) The processing unit is configured to cause the display unit to display at least one of the deterioration index and the frequency distribution. The magnetic inspection system according to any one of Items 2 to 5

[0106] (Item 7) The processing unit is configured to obtain the signal waveform based on the rate of change of magnetism of the magnetic material obtained based on the plurality of magnetic signals. The magnetic inspection system according to any one of Items 2 to 6

[0107] (Item 8) The processing unit performs preprocessing for reducing noise on the plurality of magnetic signals, and is configured to obtain the signal waveform based on the plurality of magnetic signals after the preprocessing. The magnetic inspection system according to any one of Items 2 to 7

[0108] (Item 9) The processing unit compares the deterioration index consisting of the standard deviation or the variance with a preset threshold value, and when the deterioration index is equal to or greater than the threshold value, is configured to cause the display unit to display that the degree of deterioration of the magnetic material is large. The magnetic material inspection system according to Item 4 or 5.

[0109] (Item 10) The processing unit obtains a ratio between the deterioration index consisting of the standard deviation or the variance and a reference value obtained in advance, and when the obtained ratio is equal to or greater than a predetermined value, is configured to cause the display unit to display that the degree of deterioration of the magnetic material is large. The magnetic material inspection system according to Item 4 or 5.

[0110] (Item 11) The reference value is the deterioration index obtained based on the plurality of magnetic signals measured when the magnetic material was installed. The magnetic material inspection system according to Item 10.

[0111] (Item 12) A step of obtaining the plurality of magnetic signals from the magnetic material, A step of obtaining a distribution of signal waveforms based on the plurality of magnetic signals based on the plurality of magnetic signals, A step of displaying a deterioration index indicating the degree of deterioration of the magnetic material based on the distribution of the signal waveforms. A magnetic material inspection method.

Explanation of Signs

[0112] 1 Magnetic material inspection device 2 Processing device 13 Differential coil (detection coil) 20 Display unit 21 Processing unit 30 Plurality of magnetic signals 31, 31a, 31b, 31c, 31d, 31e, 31f, 31g, 31h, 31i, 31j, 31k, 31l Signal waveforms Degree distributions of 32, 32a, 32b, 32c, 32d, 32e, 32f, 32g, 32h, 32i, 32j, 32k, 32l 40 Threshold value 41 Reference value Standard deviations of 50, 50a, 50b, 50c, 50d, 50e, 50f, 50g, 50h, 50i, 50j, 50k, 50l 51 Variance 100 Magnetic inspection system W Wire rope (magnetic material)

Claims

1. A magnetic material inspection device including a detection coil for acquiring a plurality of magnetic signals from one magnetic material; A processing device including a display unit and a processing unit, A magnetic material inspection system, wherein the processing unit is configured to acquire a signal waveform distribution based on the multiple magnetic signals acquired by the magnetic material inspection device, and to display on the display unit a deterioration index indicating the degree of deterioration of the magnetic material based on the signal waveform distribution.

2. The magnetic material inspection system of claim 1, wherein the processing unit is configured to acquire a frequency distribution of signal intensities obtained at multiple measurement positions based on the signal waveform, and to acquire the deterioration index based on the acquired frequency distribution.

3. The magnetic material inspection system according to claim 2 , wherein the processing unit is configured to obtain the deterioration index based on a shape of the frequency distribution.

4. The magnetic material inspection system according to claim 3 , wherein the processing unit is configured to obtain a standard deviation or a variance of the frequency distribution as the deterioration index based on a shape of the frequency distribution.

5. 5. The magnetic material inspection system according to claim 4, wherein the deterioration index is configured so that a larger value of the standard deviation or the variance indicates that deterioration of the magnetic material is more advanced.

6. The magnetic material inspection system according to claim 2 , wherein the processing unit is configured to cause the display unit to display at least one of the deterioration index and the frequency distribution.

7. The magnetic material inspection system according to claim 2 , wherein the processing unit is configured to acquire the signal waveform based on a rate of change of the magnetic property of the magnetic material acquired based on the plurality of magnetic signals.

8. The magnetic material inspection system of claim 2, wherein the processing unit is configured to perform preprocessing on the plurality of magnetic signals to reduce noise, and to acquire the signal waveform based on the plurality of magnetic signals after preprocessing.

9. The magnetic material inspection system of claim 4, wherein the processing unit is configured to compare the deterioration index consisting of the standard deviation or the variance with a predetermined threshold value, and when the deterioration index is equal to or greater than the threshold value, to cause the display unit to display that the degree of deterioration of the magnetic material is large.

10. The magnetic material inspection system of claim 4, wherein the processing unit is configured to acquire a ratio between the deterioration index consisting of the standard deviation or the variance and a reference value acquired in advance, and to cause the display unit to display that the degree of deterioration of the magnetic material is large when the acquired ratio is equal to or greater than a predetermined value.

11. The magnetic material inspection system according to claim 10 , wherein the reference value is the deterioration index obtained based on the plurality of magnetic signals measured when the magnetic material is installed.

12. acquiring the plurality of magnetic signals from a magnetic body; acquiring a distribution of signal waveforms based on the plurality of magnetic signals based on the plurality of magnetic signals; and displaying a deterioration index indicating a degree of deterioration of the magnetic material based on the distribution of the signal waveform.

Images