阅读说明：本技术 钢丝绳检查系统和钢丝绳检查方法 (Wire rope inspection system and wire rope inspection method ) 是由 伊藤康展 潮亘 山冈信行 于 2020-04-07 设计创作，主要内容包括：钢丝绳检查系统具备控制部,该控制部进行以下控制：基于测定日期时间互不相同的第一测定数据(201a)和第二测定数据(201b)来检查钢丝绳的状态。控制部构成为：以使第一测定数据(201a)的电梯的检查动作开始点(203)与第二测定数据(201b)的电梯的检查动作开始点(203)一致的方式进行第一测定数据和第二测定数据的波形的位置对准。(The wire rope inspection system is provided with a control unit which performs the following control: the state of the wire rope is checked based on first measurement data (201a) and second measurement data (201b) having different measurement dates and times. The control unit is configured to: the waveform of the first measurement data and the waveform of the second measurement data are aligned so that the inspection operation starting point (203) of the elevator of the first measurement data (201a) and the inspection operation starting point (203) of the elevator of the second measurement data (201b) coincide with each other.)

1. A wire rope inspection system is provided with:

a detection coil that detects a change in a magnetic field of a wire rope for driving the elevator; and

a control unit which performs the following control: checking the state of the wire rope based on first measurement data and second measurement data which are acquired by the detection coil during the checking operation of the elevator and have different measurement dates and times,

wherein the control unit is configured to: an inspection operation start point of the elevator is extracted from each of the first measurement data and the second measurement data, and the waveforms of the first measurement data and the second measurement data are aligned so that the inspection operation start point of the elevator of the extracted first measurement data matches the inspection operation start point of the elevator of the second measurement data.

2. A wireline inspection system according to claim 1,

the first measurement data and the second measurement data include data of a section before the start of the inspection operation of the elevator, the section before the start of the inspection operation of the elevator being a section in which a waveform is flat,

the control unit is configured to perform the following control: the starting point of the measurement value change for the section before the start of the inspection operation of the elevator is extracted as the starting point of the inspection operation of the elevator.

3. A wireline inspection system according to claim 2,

the control unit is configured to perform the following control: a standard deviation representing a slight deviation of the measurement values of the section before the start of the inspection operation of the elevator is acquired based on the measurement values of the section before the start of the inspection operation of the elevator, and a change start point of the measurement values is determined in consideration of the acquired standard deviation.

4. A wireline inspection system according to claim 3,

the control unit is configured to perform the following control: a threshold value for determining a start point of change in the measurement value is acquired based on the standard deviation, and a point at which the measurement value exceeds the threshold value is determined as the start point of change in the measurement value.

5. A wireline inspection system in accordance with claim 4,

the control unit is configured to perform the following control: the start point of a section in which the measurement value continuously exceeds the threshold value is determined as the change start point of the measurement value.

6. A wireline inspection system according to claim 1,

the control unit is configured to perform the following control: and adjusting a position of a waveform of at least one of the first measurement data and the second measurement data based on a similarity between the first measurement data and the second measurement data after the alignment of the waveforms in a state where the waveforms of the first measurement data and the second measurement data are aligned so that inspection operation start points of the elevator coincide with each other.

7. A wireline inspection system in accordance with claim 6,

the control unit is configured to perform the following control: the first measurement data and the second measurement data after the alignment of the waveform are divided into a plurality of divided sections, and the position of the waveform of at least one of the first measurement data and the second measurement data is adjusted in the divided sections based on the similarity.

8. A wireline inspection system according to claim 1,

the control unit is configured to perform the following control: acquiring a difference between the first measurement data and the second measurement data after the waveform is aligned, and checking a state of the wire rope based on the acquired difference.

9. A steel wire rope inspection method comprises the following steps:

detecting a change in a magnetic field of a wire rope for driving an elevator; and

checking the state of the wire rope based on first measurement data and second measurement data which are acquired during the checking operation of the elevator and have different measurement dates and times,

the step of checking the state of the wire rope comprises the steps of:

extracting an inspection operation start point of the elevator from each of the first measurement data and the second measurement data; and

the alignment of the waveforms of the first measurement data and the second measurement data is performed so that the inspection operation start point of the elevator of the extracted first measurement data matches the inspection operation start point of the elevator of the second measurement data.

Technical Field

The present invention relates to a wire rope inspection system and a wire rope inspection method.

Background

Conventionally, a wire rope inspection device for inspecting a state of a wire rope is known. Such a structure is disclosed in, for example, international publication No. 2018/138850.

The above-mentioned international publication No. 2018/138850 discloses an inspection apparatus for inspecting the condition of a wire. The inspection apparatus includes a detection coil for detecting a change in a magnetic field of the wire, and an electronic circuit unit for determining a state of the wire based on a signal from the detection coil. Further, the above-mentioned international publication No. 2018/138850 discloses that the inspection apparatus is used for an X-ray imaging apparatus, a cableway, an elevator, and the like.

Documents of the prior art

Patent document

Patent document 1: international publication No. 2018/138850

Disclosure of Invention

Problems to be solved by the invention

Although not specifically described in the above international publication No. 2018/138850, there is a technique of inspecting a wire rope by using two pieces of measurement data having different measurement dates and times. In this technique, the waveforms of two pieces of measurement data having different measurement dates and times are aligned, and the difference (difference) between the two pieces of measurement data after the alignment of the waveforms is obtained. Then, the state of the wire rope is checked based on the acquired difference. Thus, the state of the wire rope is inspected in a state where noise due to the unique magnetic characteristics of the wire rope is removed.

When the waveform of the measurement data of the above-described technique is aligned, the wire rope inspection device acquires information (such as information of an encoder of the elevator) on the position of the wire rope from the elevator, and if the information is associated with the measurement data, the corresponding point of the measurement data is easily known, and therefore, the waveform of the measurement data can be easily aligned. However, when the wire rope inspection device cannot acquire information on the position of the wire rope from the elevator, the corresponding point between the measurement data is not known, and therefore, there is a problem that it is difficult to align the waveform between the measurement data.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a wire rope inspection system and a wire rope inspection method capable of performing alignment of waveforms between measurement data by simple processing even when information on the position of a wire rope cannot be acquired from an elevator.

Means for solving the problems

In order to achieve the above object, a wire rope inspection system according to a first aspect of the present invention includes: a detection coil that detects a change in a magnetic field of a wire rope for driving the elevator; and a control unit that performs the following control: the state of the wire rope is inspected based on first measurement data and second measurement data which are acquired by a detection coil during the inspection operation of the elevator and have different measurement dates and times, wherein the control part is configured to: the inspection operation starting point of the elevator is extracted from each of the first measurement data and the second measurement data, and the waveform of the first measurement data and the waveform of the second measurement data are aligned so that the inspection operation starting point of the elevator of the extracted first measurement data and the inspection operation starting point of the elevator of the second measurement data match each other.

A steel wire rope inspection method according to a second aspect of the present invention includes the steps of: detecting a change in a magnetic field of a wire rope for driving an elevator; and inspecting a state of the wire rope based on first measurement data and second measurement data which are acquired during an inspection operation of the elevator and have different measurement dates and times, wherein the inspecting the state of the wire rope comprises the following steps: extracting an inspection operation starting point of the elevator from the first measurement data and the second measurement data; and performing the alignment of the waveforms of the first measurement data and the second measurement data so that the inspection operation start point of the elevator of the extracted first measurement data matches the inspection operation start point of the elevator of the second measurement data.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, the start point of the inspection operation of the elevator (i.e., information on the position of the wire rope) is extracted from the measurement data as described above, and the waveform of the measurement data is aligned with the waveform of the measurement data. Thus, even if information on the position of the wire rope cannot be acquired from the elevator, the waveform of the measurement data can be aligned. In addition, since the inspection operation starting points extracted from the respective measurement data need only be matched in order to perform the alignment of the waveforms between the measurement data, the alignment of the waveforms between the measurement data can be performed by a simple process. As a result, even when information on the position of the wire rope cannot be acquired from the elevator, the waveform of the measurement data can be aligned by simple processing.

Drawings

Fig. 1 is a schematic diagram showing a configuration of a wire rope inspection system according to an embodiment.

Fig. 2 is a schematic diagram showing an elevator using a wire rope inspected by a wire rope inspection device of an embodiment.

Fig. 3 is a block diagram showing a control structure of the wire rope inspection device according to the embodiment.

Fig. 4 is a diagram for explaining the configurations of the magnetic field applying unit and the detecting unit of the magnetic substance inspection device according to the embodiment.

Fig. 5 is a diagram for explaining the characteristic magnetic characteristics of the steel cord of the embodiment.

Fig. 6 is a diagram showing output waveforms of first measurement data, second measurement data, and a difference between the first measurement data and the second measurement data acquired by the wire rope inspection device according to the embodiment.

Fig. 7 is a diagram for explaining an inspection operation of an elevator according to one embodiment.

Fig. 8 is a diagram for explaining measurement data at the time of an inspection operation of an elevator according to one embodiment.

Fig. 9 is an enlarged view of the section before the start of operation of the measurement data of fig. 8, i.e., the vicinity of the start of the inspection operation.

Fig. 10 is an enlarged view of the vicinity of a section of a predetermined width of the measurement data of fig. 9.

Fig. 11 (a) is a diagram for explaining a case where the wire rope inspection device according to one embodiment determines a measurement point exceeding a threshold value as an inspection operation start point of an elevator. Fig. 11 (B) is a diagram for explaining a case where the wire rope inspection device according to one embodiment does not determine the measurement point exceeding the threshold value as the starting point of the inspection operation of the elevator.

Fig. 12 is a diagram showing first measurement data and second measurement data after alignment of waveforms according to one embodiment.

Fig. 13 is a diagram for explaining the adjustment of the positions of the first measurement data and the second measurement data after the alignment of the waveform according to the embodiment.

Fig. 14 is a diagram for explaining the adjustment of the position of each divided section of the first measurement data and the second measurement data after the alignment of the waveform according to the embodiment.

Fig. 15 is a diagram for explaining the adjustment of the position of the second divided section in fig. 14.

Detailed Description

Hereinafter, embodiments in which the present invention is implemented will be described based on the drawings.

First, the overall configuration of a wire rope inspection system 100 according to one embodiment will be described with reference to fig. 1 to 6.

(Structure of wire rope inspection System)

As shown in fig. 1, a wire rope inspection system 100 is a system for inspecting a wire rope 101 as an inspection object. The wire rope inspection system 100 includes a wire rope inspection device 200 that magnetically detects a state of a wire rope 101; and an external device 300 that analyzes the state of the wire rope 101. The wire rope inspection system 100 is configured to inspect a wire rope 101 for damage by the wire rope inspection device 200 and the external device 300.

Further, the damage of the wire rope 101 refers to a broad concept including: a change in cross-sectional area with respect to the probe direction due to abrasion, local wear, wire breakage, dent, corrosion, cracking, fracture, or the like (including a change due to a void when a flaw or the like occurs inside the wire rope 101), a change in magnetic permeability due to rust of the wire rope 101, welding burn, inclusion of impurities, a change in composition, or the like, and other portions where the wire rope 101 becomes uneven.

(Steel wire rope inspection device)

As shown in fig. 2, the wire rope inspection device 200 inspects the wire rope 101 while relatively moving along the surface of the wire rope 101 as an inspection object. The wire rope 101 is a movable rope for driving the elevator 400. The elevator 400 includes a car portion 401; an elevator (an upper winding in japanese) 402 that winds up the wire rope 101 to raise and lower the car portion 401; and a position sensor 403 that detects the position of the car portion 401 (the wire rope 101). In the elevator 400, since the wire rope 101 is moved by the hoisting machine 402, the inspection is performed in accordance with the movement of the wire rope 101 in a state where the wire rope inspection device 200 is fixed. The wire rope 101 is arranged to extend in the X direction at the position of the wire rope inspection device 200.

As shown in fig. 3, the wire rope inspection device 200 includes a probe unit 1 and an electronic circuit unit 2. The probe unit 1 includes a probe coil 10 and an excitation coil 13, and the probe coil 10 is a differential coil having a pair of receiving coils 11 and 12. The electronic circuit section 2 includes a control section 21, a reception I/F22, a storage section 23, an excitation I/F24, a power supply circuit 25, and a communication section 26. The wire rope inspection device 200 includes a magnetic field applying unit 4 (see fig. 4).

The wire rope inspection device 200 is communicably connected to the external device 300 via the communication unit 26.

As shown in fig. 1, the external device 300 includes a communication unit 301, a control unit 302, a display unit 303, and a storage unit 304. The external device 300 is configured to receive measurement data of the wire rope 101 obtained by the wire rope inspection device 200 via the communication unit 301. The external device 300 is configured to analyze the type of damage such as wire breakage or a change in cross-sectional area based on the received measurement data of the wire rope 101 by the control unit 302. The external device 300 is configured to display the analysis result on the display unit 303. The external device 300 is configured to perform abnormality determination based on the analysis result and display the result on the display unit 303. The external device 300 is configured to store measurement data, analysis results, and the like of the wire rope 101 in the storage unit 304.

As shown in fig. 4, the wire rope inspection apparatus 200 is configured to detect a change in the magnetic field (magnetic flux) of the wire rope 101 by the detection coil 10. The wire rope inspection device 200 is configured such that no dc magnetizer is disposed near the coil.

Further, the change in the magnetic field refers to a broad concept including the following changes: a change over time in the strength of the magnetic field detected by the detector 1 due to the relative movement of the wire rope 101 and the detector 1; and a temporal change in the strength of the magnetic field detected by the detection unit 1 due to a temporal change in the magnetic field applied to the wire rope 101.

The wire rope inspection device 200 is configured to remove noise data (a change in a unique magnetic characteristic) included in measurement data of the wire rope 101 based on measurement data (first measurement data 201a and second measurement data 201b described later) whose measurement dates and times are different from each other. The details will be described later.

(Structure and Property of Steel wire rope)

The steel cord 101 is formed by braiding (for example, by strand braiding) a wire material having magnetic properties. The wire rope 101 is, for example, a steel wire rope (wire rope). The wire rope 101 is a magnetic body made of a long material extending in the X direction. The state of the wire rope 101 (presence or absence of damage, etc.) is monitored to prevent the occurrence of cutting due to deterioration. Then, the wire rope 101 whose deterioration has progressed more than a predetermined amount is replaced.

The wire rope 101 has a characteristic magnetic characteristic. The unique magnetic properties are magnetic properties that change due to differences in the uniformity of twist, the uniformity of the amount of steel material, and the like at the cross-sectional position of the wire rope 101 that is orthogonal to the longitudinal direction (X direction). Here, the uniformity of the twisting of the wire rope 101 and the uniformity of the amount of steel material do not substantially change with time (or hardly change significantly with time). Therefore, since the wire rope 101 has a unique magnetic characteristic, the output at each position in the longitudinal direction (X direction) of the wire rope 101 is substantially the same (measurement with good reproducibility) at each measurement performed by the wire rope inspection device 200 at different time points from each other.

Specifically, as shown in fig. 5 (a), the output at a predetermined position in the longitudinal direction of the wire rope 101 obtained by the first measurement performed by the wire rope inspection device 200 is substantially the same as the output at a predetermined position in the longitudinal direction of the wire rope 101 obtained by the second measurement after the first measurement as shown in fig. 5 (B).

Therefore, when the difference (difference) is obtained at substantially the same position in the longitudinal direction (X direction) of the wire rope, an output waveform having a small amplitude as shown in fig. 5 (C) can be obtained after removing the unique noise data. That is, the outputs based on the changes in the characteristic magnetic characteristics of the wire rope 101 at the first measurement and the second measurement are cancelled out, and a relatively flat output waveform as shown in fig. 5 (C) is obtained. Such a result can be obtained similarly even when the period between the first measurement and the second measurement is either a relatively short period (several seconds or several minutes) or a relatively long period (several months or several years).

(Structure of magnetic field applying part)

As shown in fig. 4, the magnetic field applying unit 4 is configured to: a magnetic field is applied in advance to the wire rope 101 as an inspection object in the Y direction (the direction intersecting the direction in which the wire rope 101 extends), and the magnitude and direction of magnetization of the wire rope 101 as a magnetic body are adjusted. In addition, the magnetic field applying part 4 includes a first magnetic field applying part including the magnets 41 and 42 and a second magnetic field applying part including the magnets 43 and 44. The first magnetic field applying unit (magnets 41 and 42) is disposed on one side (X1 direction side) in the direction in which the wire rope 101 extends with respect to the detecting unit 1. The second magnetic field applying unit (magnets 43 and 44) is disposed on the other side (the X2 direction side) in the direction in which the wire rope 101 extends with respect to the detecting unit 1.

The first magnetic field applying unit (magnets 41 and 42) is configured to apply a magnetic field in the Y2 direction in parallel with a plane intersecting the direction in which the wire rope 101 extends (X direction). The second magnetic field applying unit (magnets 43 and 44) is configured to apply a magnetic field in the Y1 direction in parallel with a plane intersecting the direction in which the wire rope 101 extends (X direction). That is, the magnetic field applying unit 4 is configured to apply a magnetic field in a direction substantially orthogonal to the X direction, which is the longitudinal direction of the long material.

(Structure of Probe section)

The search coil 10 (the reception coils 11 and 12) and the excitation coil 13 are wound a plurality of times along the longitudinal direction with the direction in which the wire rope 101, which is a magnetic body made of a long material, extends as the central axis. The search coil 10 and the excitation coil 13 are coils including lead portions formed in a cylindrical shape along the X direction (longitudinal direction) in which the wire rope 101 extends. Therefore, the surfaces of the lead portions of the search coil 10 and the excitation coil 13 wound around are substantially perpendicular to the longitudinal direction. The wire rope 101 passes through the inside of the detection coil 10 and the excitation coil 13. In addition, the detection coil 10 is disposed inside the excitation coil 13. Further, the configuration of the detection coil 10 and the excitation coil 13 is not limited thereto. The receiving coil 11 of the search coil 10 is disposed on the X1 direction side. The receiving coil 12 of the search coil 10 is disposed on the X2 direction side. The receiving coils 11 and 12 are disposed at intervals of about several mm to several cm.

The excitation coil 13 is used to excite the magnetized state of the wire rope 101. Specifically, an excitation ac current is caused to flow through the excitation coil 13, and a magnetic field generated by the excitation ac current is applied to the inside of the excitation coil 13 in the X direction.

The detection coil 10 is configured to transmit a differential signal of the pair of receiving coils 11 and 12. Specifically, the detection coil 10 is configured to detect a change in the magnetic field of the wire rope 101 and transmit a differential signal. The detection coil 10 is configured to detect a change in the magnetic field of the wire rope 101 as an inspection object in the X direction and output a detection signal (voltage). That is, the detection coil 10 detects a change in the magnetic field in the X direction intersecting the Y direction with respect to the wire rope 101 to which the magnetic field is applied in the Y direction by the magnetic field applying unit 4. The search coil 10 is configured to output a differential signal (voltage) based on the detected change in the magnetic field of the wire rope 101 in the X direction. In addition, the detection coil 10 is arranged to be able to detect (in an input manner) substantially all of the magnetic field generated by the excitation coil 13.

When the wire rope 101 has a defect (flaw or the like), the total magnetic flux (a value obtained by multiplying the magnetic field by the magnetic permeability and the area) of the wire rope 101 becomes smaller at the portion having the defect (flaw or the like). As a result, for example, when the receiving coil 11 is located in a place with a defect (e.g., a flaw), the absolute value of the difference in the detection voltage (differential signal) obtained by the detection coil 10 becomes large because the magnetic flux passing through the receiving coil 12 changes compared to the magnetic flux passing through the receiving coil 11. On the other hand, the differential signal at a portion having no defect (flaw or the like) is substantially zero. In this way, a clear signal (signal with a good S/N ratio) indicating the presence of a defect (flaw or the like) is detected by the detection coil 10. Thus, the electronic circuit unit 2 can detect the presence of a defect (flaw or the like) in the wire rope 101 based on the value of the differential signal.

(Structure of electronic Circuit section)

The control unit 21 of the electronic circuit unit 2 shown in fig. 3 is configured to control each unit of the wire rope inspection device 200. Specifically, the control unit 21 includes a processor such as a CPU (central processing unit), a memory, an AD converter, and the like.

The control unit 21 is configured to receive a differential signal from the detection coil 10 and detect the state of the wire rope 101. The control unit 21 is configured to perform control for exciting the exciting coil 13. Further, the control unit 21 is configured to transmit the detection result of the state of the wire rope 101 to the external device 300 via the communication unit 26.

The reception I/F22 is configured to receive a differential signal from the detection coil 10 and transmit the differential signal to the control unit 21. Specifically, the reception I/F22 includes an amplifier. The reception I/F22 is configured to amplify the differential signal of the search coil 10 and transmit the amplified signal to the control unit 21. The storage unit 23 includes a storage medium such as an HDD or SSD, and stores information such as the first measurement data 201a and the second measurement data 201 b.

The excitation I/F24 is configured to receive a control signal from the control unit 21 and control the supply of electric power to the excitation coil 13. Specifically, the excitation I/F24 controls the supply of power from the power supply circuit 25 to the excitation coil 13 based on a control signal from the control unit 21.

As shown in fig. 6 (a) to (C), the control unit 21 is configured to perform waveform alignment of first measurement data 201a acquired by the search coil 10 in the first measurement and second measurement data 201b acquired by the search coil 10 in the second measurement after the first measurement, and acquire a difference 202 (difference data) between the first measurement data 201a and the second measurement data 201b after the waveform alignment. Further, the control unit 21 is configured to perform control for checking the state of the wire rope 101 based on the acquired difference 202.

As shown in (a) to (C) of fig. 6, by obtaining a difference 202 between first measurement data 201a and second measurement data 201b after waveform alignment, an output based on a change in the unique magnetic characteristics of the wire rope 101 is cancelled. As a result, the state of the wire rope 101 can be inspected while the damaged portion and the undamaged portion of the wire rope 101 can be more clearly distinguished.

(alignment of waveform position between measurement data)

Next, the alignment of the waveforms of the first measurement data 201a and the second measurement data 201b will be described with reference to fig. 7 to 15. Specifically, the alignment of the waveforms of the first measurement data 201a and the second measurement data 201b when the information on the position of the wire rope 101 (the information of the position sensor 403) cannot be acquired from the elevator 400 will be described.

In the present embodiment, as shown in fig. 7 to 15, first, the control unit 21 performs the following control: the inspection operation starting point 203 of the elevator 400 is extracted from each of the first measurement data 201a and the second measurement data 201b (see fig. 9). The control unit 21 is configured to align (overlap) the waveforms of the first measurement data 201a and the second measurement data 201b so that the inspection operation starting point 203 of the elevator 400 of the extracted first measurement data 201a coincides with the inspection operation starting point 203 of the elevator 400 of the second measurement data 201 b. In the following description, the first measurement data 201a and the second measurement data 201b are referred to as measurement data 201 unless they need to be distinguished from each other.

< inspection operation of Elevator >

As shown in fig. 7, measurement data 201 at the time of the inspection operation of the elevator 400 is acquired by the search coil 10 by causing the elevator 400 to perform a predetermined inspection operation. During the inspection operation, the elevator 400 moves from a predetermined inspection operation start position to a predetermined inspection operation end position. From the viewpoint of obtaining the measurement data 201 suitable for the waveform alignment, the moving speed of the elevator 400 during the inspection operation can be set to a fixed speed that is lower than the moving speed of the elevator 400 during the transportation of stacked objects such as people and freight (i.e., the moving speed of the elevator 400 during normal operation).

The inspection operation is not particularly limited, and for example, a movement operation from a lowermost position as an inspection operation start position to an uppermost position as an inspection operation end position can be used. Although fig. 7 illustrates an example in which the elevator 400 ascends during the inspection operation, the moving direction of the elevator 400 during the inspection operation is not particularly limited. That is, the elevator 400 may be lowered during the inspection operation.

The wire rope inspection device 200 starts to detect the change in the magnetic field of the wire rope 101 by the search coil 10 before the start of the inspection operation of the elevator 400, and ends to detect the change in the magnetic field of the wire rope 101 by the search coil 10 after the end of the inspection operation of the elevator 400. Thereby, the measurement data 201 from before the start of the examination operation to after the end of the examination operation is acquired by the search coil 10.

< measurement data during inspection operation of Elevator >

Measurement data 201 acquired by the search coil 10 during an inspection operation of the elevator 400 will be described with reference to fig. 8. In the graph shown in fig. 8, the vertical axis represents the output value (voltage value, etc.) of the search coil 10 at the time of measurement, and the horizontal axis represents the time at the time of measurement. Note that the vertical axis and the horizontal axis of the graphs in fig. 9, 10, 12, 14, and 15 are also the same as those in fig. 8.

As shown in fig. 8, the measurement data 201 includes data of a section before the start of the inspection operation of the elevator 400 and data of a section during the inspection operation of the elevator 400. In the data of the section before the inspection operation of the elevator 400 is started, the elevator 400 stops at the inspection operation start position and does not move, and the detection coil 10 measures the fixed point of the wire rope 101, and therefore, the data becomes a flat section in which the waveform shows a substantially constant value. On the other hand, in the data of the section in the inspection operation of the elevator 400, the elevator 400 is moved from the inspection operation start position to the inspection operation end position, and the detection coil 10 measures each point of the moving wire rope 101, and therefore, the section is a zigzag section in which the waveform does not show a substantially constant value.

In the measurement data 201, when the inspection operation of the elevator 400 is started, the measurement position at which the wire rope 101 is measured by the search coil 10 changes, and the measurement value changes rapidly.

< starting point of inspection operation for elevator extraction >

Therefore, as shown in fig. 9, the control unit 21 is configured to perform the following control: a change start point (a start point of a rapid change) of a measurement value (an output value) with respect to a section before the start of the inspection operation of the elevator 400 is extracted as an inspection operation start point of the elevator 400. At this time, the control unit 21 is configured to perform the following control: the starting point of the change of the measurement value is determined based on the measurement value of the section before the start of the inspection operation of the elevator 400.

In the example shown in fig. 9, the control unit 21 performs the following control: a measurement value of a section having a predetermined width 204 among measurement values of the section before the start of an inspection operation of the elevator 400 is extracted from the measurement data 201, and a change start point of the measurement value is determined based on the extracted measurement value of the section having the width 204. The width 204 can be set, for example, according to time, the number of measurement points (number of points), and the like. Specifically, the width 204 can be set to 0.4sec, for example.

As shown in fig. 10, as the determination control of the change start point of the measured value, first, the control unit 21 performs the following control: a standard deviation σ indicating a slight deviation (a slight fluctuation width) of the measurement values in the section before the start of the inspection operation of the elevator 400 is acquired based on the measurement values in the section before the start of the inspection operation of the elevator 400 (for example, the measurement values in the section of the width 204). Then, the control unit 21 performs the following control: the start point of change in the measured value is determined in consideration of the acquired standard deviation σ. Specifically, the control unit 21 performs the following control: the threshold 205 for determining the start point of change in the measured value is acquired based on the acquired standard deviation σ. Then, the following control is performed: the point exceeding the acquired threshold value 205 is determined as the start point of change in the measured value.

In the example shown in fig. 10, the control unit 21 performs the following control: a standard deviation σ indicating a slight deviation of the measurement values of the interval of the width 204 is acquired based on the measurement values of the interval of the width 204, and the threshold 205 is determined based on the acquired standard deviation σ. Specifically, the control unit 21 performs the following control: a value obtained by multiplying the average value of the measurement values in the interval of the width 204 by a coefficient α by a factor of 3 times (3 σ) the standard deviation σ is determined as the threshold 205. The coefficient α can be set to a value larger than 1, for example, 1.5.

As shown in fig. 11 (a) and (B), the control unit 21 is configured to perform the following control: the start point of a section having a length of a predetermined length 206, in which the measurement value continuously exceeds the threshold value 205, is determined as the change start point of the measurement value. The length 206 can be set, for example, according to time, the number of measurement points (number of points), and the like. Specifically, the length 206 can be set to 10 points, for example. In this case, the start point (first point) of the section in which the measurement value continuously exceeds the threshold value 20510 is determined as the change point of the measurement value. Further, as shown in fig. 13 (B), when the measurement value does not continuously exceed the predetermined length 206 even if the measurement value exceeds the threshold value 205, the control unit 21 does not perform control for determining a point at which the measurement value exceeds the threshold value 205 as a change start point of the measurement value.

Fig. 12 shows first measurement data 201a and second measurement data 201b obtained by extracting the inspection operation start point 203 from the first measurement data 201a without damage to the wire rope 101 and the second measurement data 201b with damage to the wire rope 101, respectively, and aligning the waveform positions so that the extracted inspection operation start points 203 coincide with each other. As shown in fig. 12, the similarity (degree of agreement) between the first measured data 201a and the second measured data 201b is 0.99. That is, the waveforms of the first measurement data 201a and the second measurement data 201b are accurately aligned.

< adjustment of positions of first measurement data and second measurement data after alignment >

As shown in fig. 13 to 15, the control unit 21 is configured to perform the following control: after the waveforms of the first measurement data 201a and the second measurement data 201b are aligned and before the difference 202 is acquired, the positions of the first measurement data 201a and the second measurement data 201b after the alignment of the waveforms are finely adjusted.

Specifically, the control unit 21 is configured to perform the following control: in a state where the waveforms of the first measurement data 201a and the second measurement data 201b are aligned so that the inspection operation start point 203 coincides with each other, the position of the waveform of at least one of the first measurement data 201a and the second measurement data 201b is adjusted based on the similarity between the first measurement data 201a and the second measurement data 201b after the alignment of the waveforms. The measurement data 201 for adjusting the position of the waveform may be only one of the first measurement data 201a and the second measurement data 201b as a reference, or may be both of the first measurement data 201a and the second measurement data 201 b.

More specifically, as shown in fig. 13 (a) and (B), the control unit 21 is configured to perform the following control: the position of the waveform of at least one of the first measurement data 201a and the second measurement data 201b is adjusted so as to be shifted in the time axis direction so that the degree of similarity increases with respect to the degree of similarity before the position adjustment. The amount of movement in the time axis direction also depends on the amount of data, but may be, for example, about several msec (several points). In fig. 13 (a), the separation distance between the first measurement data 201a and the second measurement data 201b is shown enlarged for easy understanding.

As shown in fig. 14, the control unit 21 is configured to perform the following control during the position adjustment control: the first measurement data 201a and the second measurement data 201b, which have been subjected to the waveform alignment, are divided into a plurality of divided sections 207. The divided section 207 is configured to be able to adjust the positions of the waveforms of the first measurement data 201a and the second measurement data 201b independently of the other divided sections 207. The control unit 21 is configured to perform the following control: the position of the waveform of at least one of the first measurement data 201a and the second measurement data 201b is adjusted based on the similarity in the divided section 207. That is, the control unit 21 is configured to perform the following control: the position of the waveform of at least one of the first measurement data 201a and the second measurement data 201b is adjusted independently for each of the divided sections 207 of each of the divided sections 207.

In the example shown in fig. 14, the control unit 21 performs the following control: the first measurement data 201a and the second measurement data 201b after the alignment of the waveform are divided into three divided sections, i.e., a first divided section 207a which is a section of 0 to 4 seconds, a second divided section 207b which is a section of 4 to 8 seconds, and a third divided section 207c which is a section of 8 to 12 seconds. In this case, the control unit 21 performs the following control: the similarity is obtained independently of each other in each of the first divided section 207a, the second divided section 207b, and the third divided section 207c, and the position of the waveform of at least one of the first measurement data 201a and the second measurement data 201b is adjusted so that the similarity increases.

The result of the position adjustment of the second divided section 207b shown in fig. 14 is illustrated in fig. 15. As shown in fig. 15, the adjustment amount (displacement amount) of the position was 2msec, and the similarity increased from 0.99992 to 0.99995. That is, the accuracy of the positional alignment of the waveforms of the first measurement data 201a and the second measurement data 201b is improved. Fig. 15 shows a difference 202 between the first measurement data 201a and the second measurement data 201b after the position adjustment. As the difference 202, data that can clearly distinguish the damaged portion from the non-damaged portion of the wire rope 101 is obtained.

(Effect of the present embodiment)

In the present embodiment, the following effects can be obtained.

In the present embodiment, as described above, the inspection operation start point 203 of the elevator 400 (i.e., information on the position of the wire rope 101) is extracted from the measurement data 201, and the waveform of the measurement data 201 is aligned with each other. Thus, even if information on the position of the wire rope 101 cannot be acquired from the elevator 400, the waveform of the measurement data 201 can be aligned with each other. In addition, since the inspection operation start point 203 extracted from each measurement data 201 is only required to be matched in order to align the waveforms of the measurement data 201, the waveforms of the measurement data 201 can be aligned by a simple process. As a result, even when information on the position of the wire rope 101 cannot be acquired from the elevator 400, the waveform of the measurement data 201 can be aligned by simple processing.

In the present embodiment, as described above, the first measurement data 201a and the second measurement data 201b are configured to include data of a section before the start of the inspection operation of the elevator 400, and the section before the start of the inspection operation of the elevator 400 is a section in which the waveform is flat. The control unit 21 is configured to perform the following control: the starting point of the measurement value change for the section before the start of the inspection operation of the elevator 400 is extracted as the inspection operation starting point 203 of the elevator 400. This makes it possible to extract the start point of the measurement value for the section having a flat waveform, which is easily recognized due to a rapid change, as the inspection operation start point 203 of the elevator 400, and thus it is possible to extract the inspection operation start point 203 of the elevator 400 with high accuracy.

In the present embodiment, as described above, the control unit 21 is configured to perform the following control: a standard deviation σ indicating a slight deviation of the measurement values of the section before the start of the inspection operation of the elevator 400 is acquired based on the measurement values of the section before the start of the inspection operation of the elevator 400, and a start point of the change of the measurement values is determined in consideration of the acquired standard deviation σ. Accordingly, the start point of change in the measurement value can be determined in consideration of the minute variation in the measurement value in the section before the start of the inspection operation of the elevator 400, and therefore, the minute variation in the measurement value in the section before the start of the inspection operation of the elevator 400 can be suppressed from being erroneously detected as the start point of change in the measurement value.

In the present embodiment, as described above, the control unit 21 is configured to perform the following control: a threshold value 205 for determining a start point of change in the measured value is acquired based on the standard deviation σ, and a point at which the measured value exceeds the threshold value 205 is determined as the start point of change in the measured value. Thus, the start point of change in the measured value can be determined in consideration of slight variations in the measured value in the section before the start of the inspection operation of the elevator 400 without involving complicated processing, and therefore the start point of change in the measured value can be determined easily and accurately.

In the present embodiment, as described above, the control unit 21 is configured to perform the following control: the start point of the section in which the measurement value continuously exceeds the threshold value 205 is determined as the change start point of the measurement value. Thus, since the measurement value does not exceed the threshold value 205, the measurement value change start point cannot be determined, and therefore, it is possible to suppress erroneous detection of noise as the measurement value change start point.

In the present embodiment, as described above, the control unit 21 is configured to perform the following control: in a state where the waveforms of the first measurement data 201a and the second measurement data 201b are aligned so that the inspection operation start point 203 of the elevator 400 coincides with each other, the position of the waveform of at least one of the first measurement data 201a and the second measurement data 201b is adjusted based on the similarity between the first measurement data 201a and the second measurement data 201b after the alignment of the waveforms. As a result, compared to the case where the waveforms of the first measurement data 201a and the second measurement data 201b are aligned only so that the inspection operation start point 203 of the elevator 400 coincides with each other, the similarity between the first measurement data 201a and the second measurement data 201b can be improved, and therefore the accuracy of the alignment of the waveforms of the first measurement data 201a and the second measurement data 201b can be improved.

In the present embodiment, as described above, the control unit 21 is configured to perform the following control: the first measurement data 201a and the second measurement data 201b, which have been subjected to the alignment of the waveform, are divided into a plurality of divided sections 207, and the position of the waveform of at least one of the first measurement data 201a and the second measurement data 201b is adjusted within the divided sections 207 based on the similarity. Thus, the degree of freedom of position adjustment can be improved compared to the case where the positions of the first measurement data 201a and the second measurement data 201b are adjusted over the entire section. As a result, the similarity between the first measurement data 201a and the second measurement data 201b can be further improved by the position adjustment, and therefore the accuracy of the positional alignment of the waveforms of the first measurement data 201a and the second measurement data 201b can be further improved.

In the present embodiment, as described above, the control unit 21 is configured to perform the following control: a difference 202 between the first measurement data 201a and the second measurement data 201b after the alignment of the waveform is acquired, and the state of the wire rope 101 is checked based on the acquired difference 202. This enables the state of the wire rope 101 to be inspected while noise due to the unique magnetic properties of the wire rope 101 is removed, and therefore the state of the wire rope 101 can be inspected with higher accuracy.

[ modified examples ]

The embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the claims rather than the description of the above embodiments, and includes all modifications (variations) within the meaning and scope equivalent to the claims.

For example, although the above embodiment shows an example in which the wire rope inspection device of the wire rope inspection system performs the extraction control of the start point of the inspection operation and the alignment control of the waveforms of the measurement data, the present invention is not limited to this. In the present invention, the external device of the wire rope inspection system may perform extraction control of the start point of the inspection operation and alignment control of the waveforms of the measurement data. In this case, for example, the control unit of the external device may be configured as follows: the inspection operation starting point is extracted from each of the first measurement data and the second measurement data, and the waveforms of the first measurement data and the second measurement data are aligned so that the inspection operation starting point of the elevator of the extracted first measurement data and the inspection operation starting point of the elevator of the second measurement data match each other.

In the above-described embodiment, the example in which the search coil is a differential coil having a pair of receiving coils is shown, but the present invention is not limited to this. In the present invention, the detection coil may also be constituted by a single coil.

In the above-described embodiment, the example in which the start point of change in the measurement value is determined in consideration of the standard deviation of the minute deviation of the measurement value indicating the section before the start of the inspection operation of the elevator has been described, but the present invention is not limited to this. In the present invention, the starting point of change in the measured value may be determined without considering the standard deviation of the minute deviation of the measured value indicating the section before the start of the inspection operation of the elevator. For example, the threshold value may be determined based on the maximum value or the minimum value of the measurement value in the section before the elevator inspection operation is started, and the start point of the change in the measurement value may be determined.

In the above-described embodiment, an example is shown in which the threshold value for determining the change start point of the measurement value is determined based on the measurement value of the section before the start of the inspection operation of the elevator. In the present invention, the threshold value for determining the change start point of the measurement value may be a preset value as long as the inspection operation start point can be extracted with high accuracy.

In the above-described embodiment, an example is shown in which the start point of the section in which the measurement value continuously exceeds the threshold value is determined as the change start point of the measurement value, but the present invention is not limited to this. In the present invention, a point at which the measurement value exceeds the threshold value may be determined as a change start point of the measurement value without determining whether or not the measurement value continuously exceeds the threshold value.

In the above-described embodiment, an example is shown in which fine adjustment is performed after the alignment of the waveforms of the first measurement data and the second measurement data is performed based on the similarity between the first measurement data and the second measurement data after the alignment of the waveforms is performed, but the present invention is not limited to this. In the present invention, it is not always necessary to perform fine adjustment after the waveforms of the first measurement data and the second measurement data are aligned.

In the above-described embodiment, the first measurement data and the second measurement data after the alignment of the waveforms are divided into a plurality of divided sections, and fine adjustment after the alignment of the waveforms of the first measurement data and the second measurement data is performed in the divided sections is described. In the present invention, when fine adjustment is performed after the alignment of the waveforms of the first measurement data and the second measurement data, the first measurement data and the second measurement data after the alignment of the waveforms are not necessarily divided into a plurality of divided sections. For example, fine adjustment after the alignment of the waveforms of the first measurement data and the second measurement data may be performed by moving the entire waveform of at least one of the first measurement data and the second measurement data after the alignment of the waveforms.

[ means ]

It will be appreciated by those skilled in the art that the above-described exemplary embodiments are specific in the following manner.

(item 1)

A wire rope inspection system is provided with:

a detection coil that detects a change in a magnetic field of a wire rope for driving the elevator; and

a control unit which performs the following control: checking the state of the wire rope based on first measurement data and second measurement data which are acquired by the detection coil during the checking operation of the elevator and have different measurement dates and times,

wherein the control unit is configured to: an inspection operation start point of the elevator is extracted from each of the first measurement data and the second measurement data, and the waveforms of the first measurement data and the second measurement data are aligned so that the inspection operation start point of the elevator of the extracted first measurement data matches the inspection operation start point of the elevator of the second measurement data.

(item 2)

The wire rope inspection system according to item 1, wherein the first measurement data and the second measurement data include data of a section before an inspection operation of the elevator is started, the section before the inspection operation of the elevator is a section in which a waveform is flat,

the control unit is configured to perform the following control: the starting point of the measurement value change for the section before the start of the inspection operation of the elevator is extracted as the starting point of the inspection operation of the elevator.

(item 3)

The wire rope inspection system according to item 2, wherein the control unit is configured to perform the following control: a standard deviation representing a slight deviation of the measurement values of the section before the start of the inspection operation of the elevator is acquired based on the measurement values of the section before the start of the inspection operation of the elevator, and a change start point of the measurement values is determined in consideration of the acquired standard deviation.

(item 4)

The wire rope inspection system according to item 3, wherein the control unit is configured to perform the following control: a threshold value for determining a start point of change in the measurement value is acquired based on the standard deviation, and a point at which the measurement value exceeds the threshold value is determined as the start point of change in the measurement value.

(item 5)

The wire rope inspection system according to item 4, wherein the control unit is configured to perform the following control: the start point of a section in which the measurement value continuously exceeds the threshold value is determined as the change start point of the measurement value.

(item 6)

The wire rope inspection system according to any one of items 1 to 5, wherein the control unit is configured to perform control of: and adjusting a position of a waveform of at least one of the first measurement data and the second measurement data based on a similarity between the first measurement data and the second measurement data after the alignment of the waveforms in a state where the waveforms of the first measurement data and the second measurement data are aligned so that inspection operation start points of the elevator coincide with each other.

(item 7)

The wire rope inspection system according to item 6, wherein the control unit is configured to perform the following control: the first measurement data and the second measurement data after the alignment of the waveform are divided into a plurality of divided sections, and the position of the waveform of at least one of the first measurement data and the second measurement data is adjusted in the divided sections based on the similarity.

(item 8)

The wire rope inspection system according to any one of items 1 to 7, wherein the control unit is configured to perform control of: acquiring a difference between the first measurement data and the second measurement data after the waveform is aligned, and checking a state of the wire rope based on the acquired difference.

(item 9)

A steel wire rope inspection method comprises the following steps:

detecting a change in a magnetic field of a wire rope for driving an elevator; and

checking the state of the wire rope based on first measurement data and second measurement data which are acquired during the checking operation of the elevator and have different measurement dates and times,

the step of checking the state of the wire rope comprises the steps of:

extracting an inspection operation start point of the elevator from each of the first measurement data and the second measurement data; and

the alignment of the waveforms of the first measurement data and the second measurement data is performed so that the inspection operation start point of the elevator of the extracted first measurement data matches the inspection operation start point of the elevator of the second measurement data.

Description of the reference numerals

10: a detection coil; 21: a control unit; 100: a wire rope inspection system; 101: a wire rope; 201 a: first measurement data; 201 b: second measurement data; 202: a difference; 203: checking an action starting point; 205: a threshold value; 207: dividing the interval; 400: an elevator; σ: standard deviation.