Rope Tester

Abstract

This reduces the possibility of missing a signal value due to damage to the wire. [Solution] The rope tester (1A) comprises a permanent magnet that magnetizes the rope, a detection unit that includes a plurality of first detection coils (13) and second detection coils (22) that detect magnetic flux leaking from the rope magnetized by the permanent magnet and generate electrical signals based on the detection results, a first conversion circuit (31A) and a second conversion circuit (31B) that convert each of the multiple electrical signals generated by the first detection coil (13) and the second detection coil (22), respectively, so that the signal values ​​contained in the electrical signals are all positive values, and an output cable (40) that outputs the sum of the two electrical signals converted by the first conversion circuit (31A) and the second conversion circuit (31B) to the outside.

Description

[Technical Field]

[0001] The present invention relates to a rope tester that magnetizes a wire rope and detects leakage magnetic flux generated when a wire in the wire rope is broken using a detection element. [Background technology]

[0002] For example, as disclosed in Patent Document 1, a rope tester is known in which a wire rope is magnetized with a permanent magnet and leakage magnetic flux generated when a wire in the wire rope is broken is detected by a coil. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-89172 Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology described in Patent Document 1, a detection coil is provided for each of multiple wire ropes, and the leakage magnetic flux detected by each detection coil is converted into an electric signal, and the sum of the converted electric signals is output. In this case, the signal values ​​of the electric signals cancel each other out, and there is a risk that the signal value due to damage to the wire cannot be detected.

[0005] Another possible solution is to apply detection coils to a single rope from multiple directions, convert the leakage magnetic flux detected by each detection coil into an electric signal, and output the sum of the converted electric signals. In this case, too, there is a risk that the signal values ​​of the electric signals will cancel each other out, making it impossible to detect the signal value due to damage to the wire.

[0006] One aspect of the present disclosure aims to realize a rope tester that can reduce the possibility of missing a signal value due to damage to a wire. [Means for solving the problem]

[0007] In order to solve the above problems, the rope tester according to aspect 1 of the present invention comprises a magnetization unit that magnetizes a rope, a detection unit having a plurality of detection elements that detect magnetic flux leaking from the rope magnetized by the magnetization unit and generate an electrical signal based on the detection result, a conversion unit that converts each of the electrical signals generated by each of the plurality of detection elements so that the signal values ​​contained in the electrical signal are only positive or negative values, and an output unit that outputs the sum of the electrical signals converted by the conversion unit to the outside.

[0008] According to the above configuration, the signal values ​​contained in the multiple electrical signals converted by the conversion unit are either positive or negative, so that when the multiple electrical signals are summed, the signal values ​​do not cancel each other out and peaks due to breaks in the wires of the rope do not disappear, thereby reducing the possibility of missing a signal value due to damage to the wires.

[0009] A rope tester according to aspect 2 of the present invention may be configured in the above-mentioned aspect 1 such that the detection unit detects the magnetic flux using the detection elements from multiple directions for one rope, generating multiple electrical signals for the one rope, and the output unit outputs the sum of the multiple electrical signals generated for the one rope.

[0010] According to the above configuration, the results of magnetic flux detection performed from multiple directions are used, so damage to wires in the rope can be detected more reliably than when the results of magnetic flux detection performed from a single direction are used.

[0011] A rope tester according to aspect 3 of the present invention may be configured such that, in aspect 1 above, the magnetization unit magnetizes a plurality of the ropes, and the detection unit includes at least one detection element for each of the plurality of ropes.

[0012] According to the above configuration, it is possible to detect the occurrence of wire breakage in a plurality of ropes by performing a single process.

[0013] A rope tester according to aspect 4 of the present invention may be configured in the above-mentioned aspect 3 such that the detection unit detects the magnetic flux using the detection element from multiple directions for each of the multiple ropes, and generates multiple electrical signals for each of the multiple ropes.

[0014] According to the above configuration, damage to the wires in each of the plurality of ropes can be detected more reliably than when the results of magnetic flux detection performed from a single direction are used.

[0015] A rope tester according to aspect 5 of the present invention may be configured in any one of aspects 1 to 4 above, such that the conversion unit converts the signal values ​​to only positive values ​​or only negative values ​​using an analog electrical circuit.

[0016] According to the above configuration, there is no need to provide an A / D converter, and therefore manufacturing costs can be reduced.

[0017] A rope tester according to a sixth aspect of the present invention is in any one of the first to fifth aspects, and the conversion unit may be configured to convert the signal value into an absolute value.

[0018] According to the above configuration, by converting into absolute values, each of the multiple electrical signals generated by each detection element can be converted so that the signal values ​​contained in the electrical signals are only positive values.

[0019] A rope tester according to a seventh aspect of the present invention is in any one of the first to fifth aspects, and the conversion unit may be configured to convert the signal value into a square value.

[0020] According to the above configuration, by converting into squared values, each of the multiple electrical signals generated by each detection element can be converted so that the signal values ​​contained in the electrical signals are only positive values.

[0021] A rope tester according to aspect 8 of the present invention may be configured in any one of aspects 1 to 5 above, such that the conversion unit converts the signal value of a negative value to 0, or converts the signal value of a positive value to 0.

[0022] According to the above configuration, each of the plurality of electrical signals generated by each of the detection elements can be converted so that the signal values ​​contained in the electrical signal contain only positive values ​​or only negative values. [Effects of the Invention]

[0023] According to one aspect of the present invention, it is possible to reduce the possibility of a signal value being missed due to damage to the wire. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a perspective view of a rope tester according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing the configuration of a front head provided in the rope tester. [Figure 3] 10A and 10B are diagrams showing the configuration of a back head provided in the rope tester. [Figure 4] FIG. 2 is a schematic diagram showing how the rope tester is attached to the rope. [Figure 5] FIG. 2 is a top view of the rope tester attached to the rope. [Figure 6] 1 is a cross-sectional view of a rope tester attached to a rope, taken along a plane perpendicular to the direction in which the rope is stretched and including a first detection coil and a second detection coil provided in the rope tester. [Figure 7] FIG. 2 is a diagram conceptually showing the processing of electrical signals in the rope tester. [Figure 8]The figure indicated by the reference numeral 801 is a graph showing an example of an electrical signal generated by the first detection coil, and the figure indicated by the reference numeral 802 is a graph showing an electrical signal converted from the electrical signal indicated by the reference numeral 801 by the first conversion circuit provided in the rope tester. [Figure 9] The figure indicated by the reference numeral 901 is a graph showing an example of an electrical signal generated by the second detection coil, and the figure indicated by the reference numeral 902 is a graph showing an electrical signal converted from the electrical signal indicated by the reference numeral 901 by a second conversion circuit provided in the rope tester. [Figure 10] FIG. 2 is a circuit diagram illustrating an example of an adder circuit according to the first embodiment of the present invention. [Figure 11] The diagram indicated by the reference numeral 1101 is a diagram showing the sum of the electrical signal indicated by the reference numeral 801 in FIG. 8 and the electrical signal indicated by the reference numeral 901 in FIG. 9, and the diagram indicated by the reference numeral 1102 is a diagram showing the sum of the electrical signal indicated by the reference numeral 802 in FIG. 8 and the electrical signal indicated by the reference numeral 902 in FIG. 9. [Figure 12] FIG. 10 is a diagram conceptually showing the processing of an electric signal in a rope tester according to a second embodiment of the present invention. [Figure 13] FIG. 3 is a circuit diagram showing an example of a first conversion circuit included in the rope tester. [Figure 14] FIG. 10 is a perspective view of a rope tester according to a third embodiment of the present invention. [Figure 15] FIG. 2 is a diagram conceptually showing the processing of electrical signals in the rope tester. [Figure 16] FIG. 10 is a circuit diagram illustrating an example of an adder circuit according to a third embodiment of the present invention. [Figure 17] FIG. 10 is a diagram conceptually showing the processing of an electric signal in a rope tester according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0025] [Embodiment 1] An embodiment of the present invention will be described in detail below. Fig. 1 is a perspective view of a rope tester 1A in this embodiment. The rope tester 1A is a device used to detect breaks in wires in wire ropes installed in elevators and the like. In the following description, the X-axis direction shown in Fig. 1 may be referred to as the left-right direction, the Y-axis direction as the front-rear direction, and the Z-axis direction as the up-down direction.

[0026] As shown in FIG. 1, the rope tester 1A includes a front head 10, a rear head 20, a circuit box 30A, and an output cable 40 (output section).

[0027] Fig. 2 is a diagram showing the configuration of the front head 10. In Fig. 2, the diagram indicated by reference numeral 201 is a diagram of the front head 10 seen from the +X-axis direction, the diagram indicated by reference numeral 202 is a diagram of the front head 10 seen from the -Y-axis direction, and the diagram indicated by reference numeral 203 is a diagram of the front head 10 seen from the +Z-axis direction. Note that in Fig. 2, some of the members provided inside the front head 10 are shown by dashed lines.

[0028] As shown in FIG. 2, the front head 10 includes a housing 11, a pair of permanent magnets 12, and a first detection coil 13 (detection unit).

[0029] The housing 11 has a rectangular parallelepiped shape extending in the Z-axis direction. A groove 14 extending along the Z-axis direction is formed in the surface of the housing 11 facing the rear head 20 (described later). As shown in the diagram of reference numeral 203 in Fig. 2, the bottom surface of the groove 14 has an arc shape in a cross section cut along a plane parallel to the XY plane.

[0030] The pair of permanent magnets 12 are provided inside the front head 10 near both surfaces of the front head 10 in the Z-axis direction. The pair of permanent magnets 12 are provided so that the polarities of the surfaces facing the groove 14 are opposite to each other. As a result, the pair of permanent magnets 12 function as a magnetizing section that magnetizes the rope 50 (see FIG. 4) inserted into the groove 14.

[0031] The first detection coil 13 is provided inside the front head 10, near the center of the front head 10 in the Z-axis direction. The first detection coil 13 is a detection element that detects magnetic flux leaking from the rope 50 magnetized by the pair of permanent magnets 12, and generates an electric signal based on the detection result, more specifically, an electric signal obtained by converting the magnitude of the detected magnetic flux into a voltage. The electric signal generated by the first detection coil 13 is output to the circuit box 30A via a signal line (not shown).

[0032] Fig. 3 is a diagram showing the configuration of the rear head 20. In Fig. 3, the diagram indicated by reference numeral 301 is a diagram of the rear head 20 viewed from the -X axis direction, the diagram indicated by reference numeral 302 is a diagram of the rear head 20 viewed from the -Y axis direction, and the diagram indicated by reference numeral 303 is a diagram of the rear head 20 viewed from the +Z axis direction.

[0033] 3, the rear head 20 includes a housing 21 and a second detection coil 22 (detection unit). The rear head 20 is detachable from the front head 10.

[0034] The housing 21 has a rectangular parallelepiped shape extending in the Z-axis direction. A pair of protrusions 23 extending in the Z-axis direction is formed on the housing 21 at the center in the Z-axis direction on the surface facing the front head 10. As shown in the diagram of reference numeral 303 in Fig. 3, the surfaces of the pair of protrusions 23 facing each other are arc-shaped in a cross section cut along a plane parallel to the XY plane.

[0035] The second detection coil 22 is provided inside the rear head 20, near the center of the rear head 20 in the Z-axis direction. The second detection coil 22 detects magnetic flux leaking from the rope 50 magnetized by the pair of permanent magnets 12, and generates an electric signal based on the detection result, more specifically, an electric signal obtained by converting the magnitude of the detected magnetic flux into a voltage. The electric signal generated by the second detection coil 22 is output to the circuit box 30A via a signal line (not shown).

[0036] 4 is a schematic diagram showing how the rope tester 1A is attached to the rope 50. When attaching the rope tester 1A to the rope 50, as shown in FIG. 4, the rope 50 is inserted into the groove 14 of the front head 10 with the rear head 20 removed from the front head 10, and then the rear head 20 is attached to the front head 10.

[0037] FIG. 5 is a top view of the rope tester 1A attached to the rope 50. FIG. 6 is a cross-sectional view of the rope tester 1A attached to the rope 50, taken along a plane parallel to the XY plane and including the first detection coil 13 and the second detection coil 22. As shown in FIGS. 5 and 6, when the rope tester 1A is attached to the rope 50, the rope 50 is surrounded by the groove 14 of the front head 10 and the pair of protrusions 23 of the rear head 20. Also, as shown in FIG. 6, in the rope tester 1A, the first detection coil 13 and the second detection coil 22 detect magnetic flux in opposite directions relative to the rope 50, generating two electrical signals for one rope 50.

[0038] The circuit box 30A is a housing that houses circuits that process the electrical signals output from the first detection coil 13 and the second detection coil 22. FIG. 7 is a diagram conceptually showing the processing of electrical signals in the rope tester 1A. As shown in FIG. 7, the circuit box 30A is equipped with a first conversion circuit 31A, a second conversion circuit 31B, and an adder circuit 32A as circuits that process the electrical signals output from the first detection coil 13 and the second detection coil 22.

[0039] The first conversion circuit 31A is an analog electrical circuit that converts the electrical signal generated by the first detection coil 13 so that the signal values ​​contained in the electrical signal contain only positive values. In this embodiment, the first conversion circuit 31A converts the signal values ​​contained in the electrical signal generated by the first detection coil 13 into square values, thereby converting the signal values ​​contained in the electrical signal so that the signal values ​​contained in the electrical signal contain only positive values. The first conversion circuit 31A may be a conventionally known analog multiplier, such as the AD633 manufactured by Analog Devices. By inputting the electrical signal generated by the first detection coil 13 to two input terminals of the analog multiplier, the squared values ​​of each signal value contained in the electrical signal generated by the first detection coil 13 are output. The electrical signal whose signal values ​​have been converted by the first conversion circuit 31A is output to the adder circuit 32A.

[0040] The second conversion circuit 31B is an analog electrical circuit that converts the electrical signal generated by the second detection coil 22 so that the signal values ​​contained in the electrical signal contain only positive values. In this embodiment, the second conversion circuit 31B converts the signal values ​​contained in the electrical signal generated by the second detection coil 22 into square values, thereby converting the signal values ​​contained in the electrical signal so that the signal values ​​contained in the electrical signal contain only positive values. The second conversion circuit 31B is configured with the same circuitry as the first conversion circuit 31A. The electrical signal whose signal value has been converted by the second conversion circuit 31B is output to the adder circuit 32A.

[0041] The diagram indicated by reference numeral 801 in Fig. 8 is a graph showing an example of an electrical signal generated by the first detection coil 13, and the diagram indicated by reference numeral 802 in Fig. 8 is a graph showing an electrical signal obtained by converting the electrical signal indicated by reference numeral 801 by the first conversion circuit 31A. In the example indicated by reference numeral 801 in Fig. 8, a peak indicating the detection of leakage magnetic flux due to breakage of the wires of the rope 50 is shown in the range of 500 to 600 ms.

[0042] The diagram indicated by reference numeral 901 in Fig. 9 is a graph showing an example of an electrical signal generated by the second detection coil 22, and the diagram indicated by reference numeral 902 in Fig. 9 is a graph showing an electrical signal obtained by converting the electrical signal indicated by reference numeral 901 by the second conversion circuit 31B. In the example indicated by reference numeral 901 in Fig. 9, a peak indicating the detection of leakage magnetic flux caused by a break in the wires of the rope 50 is shown in the range of 500 to 700 ms. Note that the electrical signal indicated by the graph indicated by reference numeral 801 in Fig. 8 and the electrical signal indicated by the graph indicated by reference numeral 901 in Fig. 9 are electrical signals based on the detection results detected at the same timing by the first detection coil 13 and the second detection coil 22, respectively.

[0043] 8 and 9, by converting the electrical signal generated by the first detection coil 13 using the first conversion circuit 31A, the signal value of the electrical signal output from the first conversion circuit 31A can be limited to positive values. Also, by converting the electrical signal generated by the second detection coil 22 using the second conversion circuit 31B, the signal value of the electrical signal output from the second conversion circuit 31B can be limited to positive values.

[0044] The adder circuit 32A is a circuit that generates the sum of the electrical signals converted by the first conversion circuit 31A and the second conversion circuit 31B. Fig. 10 is a circuit diagram showing an example of the adder circuit 32A. As shown in Fig. 10, the adder circuit 32A may be configured by a circuit using an operational amplifier.

[0045] 11 is a diagram showing the sum of the electrical signal indicated by reference numeral 801 in Fig. 8 and the electrical signal indicated by reference numeral 901 in Fig. 9, and the diagram indicated by reference numeral 1102 in Fig. 11 is a diagram showing the sum of the electrical signal indicated by reference numeral 802 in Fig. 8 and the electrical signal indicated by reference numeral 902 in Fig. 9. In other words, the diagram indicated by reference numeral 1101 in Fig. 11 is a diagram showing the sum of the electrical signal generated by the first detection coil 13 and the electrical signal generated by the second detection coil 22, and is a diagram showing the sum of the electrical signal obtained by converting the electrical signal generated by the first detection coil 13 using the first conversion circuit 31A and the electrical signal obtained by converting the electrical signal generated by the second detection coil 22 using the second conversion circuit 31B.

[0046] As described above, the electric signal indicated by reference numeral 801 in Fig. 8 has a peak in the range of 500 to 600 ms, and the electric signal indicated by reference numeral 901 in Fig. 9 has a peak in the range of 500 to 700 ms, with the ranges in which the peaks partially overlap. Therefore, in the electric signal generated by taking the sum of the electric signal indicated by reference numeral 801 in Fig. 8 and the electric signal indicated by reference numeral 901 in Fig. 9, the signal values ​​of the electric signal indicated by reference numeral 801 in Fig. 8 and the electric signal indicated by reference numeral 901 in Fig. 9 cancel each other out, as indicated by reference numeral 1101 in Fig. 11, and some of the peaks due to breaks in the wires of the rope 50 disappear. Therefore, when leakage magnetic flux is detected using the electric signal indicated by reference numeral 1101 in Fig. 11, detection of a signal value due to damage to the wires will be missed.

[0047] In contrast, the electric signal generated by summing the electric signal indicated by reference numeral 802 in Fig. 8 and the electric signal indicated by reference numeral 902 in Fig. 9 contains only positive signal values, and therefore the signal values ​​of the electric signals do not cancel each other out. Therefore, the electric signal generated by summing the electric signal indicated by reference numeral 802 in Fig. 8 and the electric signal indicated by reference numeral 902 in Fig. 9 retains all of the peaks due to breaks in the wires of the rope 50, as indicated by reference numeral 1102 in Fig. 11. Therefore, when leakage magnetic flux is detected using the electric signal indicated by reference numeral 1102 in Fig. 11, in other words, the electric signal generated by summing the electric signal generated by the first detection coil 13 converted by the first conversion circuit 31A and the electric signal generated by the second detection coil 22 converted by the second conversion circuit 31B, the possibility of missing a signal value due to damage to the wires can be reduced.

[0048] The output cable 40 is a cable that outputs to the outside the sum of the electrical signals converted by the first conversion circuit 31A and the second conversion circuit 31B, which are generated by the addition circuit 32A. The electrical signal output from the output cable 40 is converted into a digital signal by an A / D converter (not shown) and then input to an information processing device such as a computer. The digital electrical signal is then analyzed by the information processing device, which determines whether or not a break has occurred in the wires of the rope 50.

[0049] The rope tester 1A in this embodiment outputs only one electrical signal generated by the adder circuit 32A, and therefore the rope tester 1A only needs to have one output cable 40. This reduces the number of A / D converters required to one.

[0050] As described above, in the rope tester 1A of this embodiment, the first conversion circuit 31A converts the electrical signal generated by the first detection coil 13 so that the signal values ​​contained in the electrical signal are all positive, and the second conversion circuit 31B converts the electrical signal generated by the second detection coil 22 so that the signal values ​​contained in the electrical signal are all positive. The adder circuit 32A then sums the two electrical signals converted by the first conversion circuit 31A and the second conversion circuit 31B, and outputs the sum via the output cable 40. This configuration allows for the use of a single output cable 40 and reduces the possibility of missing a signal value due to damage to the wire.

[0051] Furthermore, in the rope tester 1A of this embodiment, magnetic flux is detected from two directions for one rope 50 by the first detection coil 13 and the second detection coil 22, two electric signals are generated for one rope 50, and the sum of the two electric signals generated for one rope 50 is output. This makes it possible to more reliably detect damage to the wires in the rope 50 compared to when the results of magnetic flux detection from a single direction are used.

[0052] Furthermore, in the rope tester 1A of this embodiment, the first conversion circuit 31A and the second conversion circuit 31B, which are analog electrical circuits, convert the electrical signals generated by the first detection coil 13 and the second detection coil 22 so that only positive signal values ​​are included in the electrical signals. This eliminates the need for an A / D converter, thereby reducing manufacturing costs. However, in one aspect of the present invention, instead of the first conversion circuit 31A and the second conversion circuit 31B, two A / D converters corresponding to the first conversion circuit 31A and the second conversion circuit 31B, respectively, may be provided, and the sum of the two electrical signals converted by the two A / D converters may be output to the outside.

[0053] In the rope tester 1A of the present embodiment, the detection coils (first detection coil 13 and second detection coil 22) are used to detect magnetic flux leaking from the rope 50 and generate an electric signal based on the detection result, but the rope tester of the present invention is not limited to this. A rope tester of one aspect of the present invention may be configured to detect magnetic flux leaking from the rope 50 using a Hall element and generate an electric signal based on the detection result.

[0054] [Embodiment 2] Other embodiments of the present invention will be described below. For ease of explanation, the same reference numerals will be used to designate components having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

[0055] In the rope tester 1A of the first embodiment, the first conversion circuit 31A and the second conversion circuit 31B convert the signal values ​​included in the electric signals generated by the first detection coil 13 and the second detection coil 22 into square values, thereby converting the signal values ​​included in the electric signals so that only positive values ​​are included. In contrast, in the rope tester 1B of the present embodiment, the signal values ​​included in the electric signals generated by the first detection coil 13 and the second detection coil 22 are converted into absolute values, thereby converting the signal values ​​included in the electric signals so that only positive values ​​are included.

[0056] Fig. 12 is a diagram conceptually illustrating the processing of electrical signals in a rope tester 1B. As shown in Fig. 12, the rope tester 1B includes a circuit box 30B instead of the circuit box 30A in embodiment 1. The circuit box 30B includes a first conversion circuit 31C and a second conversion circuit 31D instead of the first conversion circuit 31A and the second conversion circuit 31B in embodiment 1.

[0057] The first conversion circuit 31C converts the signal values ​​contained in the electrical signal generated by the first detection coil 13 into absolute values, thereby converting the signal values ​​contained in the electrical signal so that only positive values ​​are included. FIG. 13 is a circuit diagram showing an example of the first conversion circuit 31C. In the rope tester 1B, the first conversion circuit 31C, which converts the signal values ​​contained in the electrical signal into absolute values, such as the full-wave rectifier circuit shown in FIG. 13, converts the electrical signal generated by the first detection coil 13 so that only positive values ​​are included in the electrical signal, and outputs the converted signal to the adder circuit 32A. Note that the first conversion circuit 31C may be configured as a full-wave rectifier circuit using a diode bridge.

[0058] The second conversion circuit 31D converts the signal values ​​contained in the electrical signal generated by the second detection coil 22 into absolute values, thereby converting the signal values ​​contained in the electrical signal so that only positive values ​​are included. The second conversion circuit 31D is configured with the same circuitry as the first conversion circuit 31C. In the rope tester 1B, the second conversion circuit 31D, which converts the signal values ​​contained in the electrical signal into absolute values, converts the electrical signal generated by the second detection coil 22 so that only positive values ​​are included in the electrical signal, and outputs the converted signal to the addition circuit 32A.

[0059] According to the above configuration, the first conversion circuit 31C converts the electrical signal generated by the first detection coil 13 so that the signal values ​​contained in the electrical signal are all positive, and the second conversion circuit 31D converts the electrical signal generated by the second detection coil 22 so that the signal values ​​contained in the electrical signal are all positive. The adder circuit 32A then sums the two electrical signals converted by the first conversion circuit 31C and the second conversion circuit 31D, respectively, and outputs the sum via the output cable 40. According to this configuration, when the adder circuit 32A generates the sum of the two electrical signals converted by the first conversion circuit 31C and the second conversion circuit 31D, respectively, the signal values ​​can be prevented from canceling each other out. As a result, all peaks due to breaks in the wires of the rope 50 remain in the sum of the two electrical signals converted by the first conversion circuit 31C and the second conversion circuit 31D, respectively, generated by the adder circuit 32A. This reduces the possibility of missed detection of signal values ​​due to damage to the wires.

[0060] In one aspect of the present invention, the rope tester may include two half-wave rectifier circuits instead of the first conversion circuit 31C and the second conversion circuit 31D, which are full-wave rectifier circuits. The half-wave rectifier circuit sets negative or positive signal values ​​contained in a signal to zero. This configuration also prevents the signal values ​​from canceling each other out when the sum of the two electrical signals converted by the two half-wave rectifier circuits is generated by the adder circuit 32A. As a result, the possibility of missing a signal value due to damage to the wire can be reduced.

[0061] [Embodiment 3] Another embodiment of the present invention will be described below. Fig. 14 is a perspective view of a rope tester 1C in this embodiment. As shown in Fig. 14, the rope tester 1C includes five front heads 10A to 10E, five rear heads 20A to 20E, a circuit box 30C, and an output cable 40.

[0062] The front heads 10A to 10E have the same configuration as the front head 10 in embodiment 1. As shown in Fig. 14, in the rope tester 1C, the front heads 10A to 10E are arranged in parallel in the order of front head 10A, front head 10B, front head 10C, front head 10D, and front head 10E from the circuit box 30C side toward the -Y direction.

[0063] The rear heads 20A to 20E have the same configuration as the rear head 20 in embodiment 1. As shown in Fig. 14, in the rope tester 1C, the rear heads 20A to 20E are arranged in parallel in the -Y direction from the circuit box 30C side in the order of rear head 20A, rear head 20B, rear head 20C, rear head 20D, and rear head 20E. The rear heads 20A to 20E are detachable from the front heads 10A to 10E, respectively.

[0064] When attaching the rope tester 1C to the rope 50, the rear heads 20A to 20E are removed from the front heads 10A to 10E, respectively, and one rope 50 is inserted into the groove provided in each of the front heads 10A to 10E, and then the rear heads 20A to 20E are attached to the front heads 10A to 10E, respectively.

[0065] In the rope tester 1C, the rope 50 is magnetized by a pair of permanent magnets 12 provided in the front head 10A, and the first detection coil 13 provided in the front head 10A and the second detection coil 22 provided in the back head 20A detect magnetic flux from opposite directions for one rope 50, generating two electric signals for that one rope 50. Similarly, two electric signals are generated for one rope 50 by the front head 10B and the back head 20B, the front head 10C and the back head 20C, the front head 10D and the back head 20D, and the front head 10E and the back head 20E, respectively.

[0066] The circuit box 30C is a housing that houses circuits that process the electrical signals output from the first detection coils 13 of the front heads 10A to 10E and the second detection coils 22 of the rear heads 20A to 20E. Fig. 15 is a diagram conceptually showing the processing of electrical signals in the rope tester 1C. As shown in Fig. 15, the circuit box 30C includes conversion circuits 34A to 34J (conversion units) and an addition circuit 32B.

[0067] The conversion circuits 34A to 34J are analog electrical circuits that convert the signal values ​​contained in the electrical signals so that only positive values ​​are included. The conversion circuits 34A to 34J may be the same circuit as the first conversion circuit 31A in the first embodiment. As shown in FIG. 15, the conversion circuits 34A, 34C, 34E, 34G, and 34I each convert the electrical signals generated by the first detection coils 13 included in the front heads 10A to 10E so that only positive values ​​are included in the electrical signals. The conversion circuits 34B, 34D, 34F, 34H, and 34J each convert the electrical signals generated by the second detection coils 22 included in the rear heads 20A to 20E so that only positive values ​​are included in the electrical signals. The electrical signals whose signal values ​​have been converted by the conversion circuits 34A to 34J are output to the adder circuit 32B.

[0068] The adder circuit 32B is a circuit that generates the sum of the electrical signals converted by the conversion circuits 34A to 34J. Fig. 16 is a circuit diagram showing an example of the adder circuit 32B. As shown in Fig. 16, the adder circuit 32B may be configured by a circuit that uses an operational amplifier and outputs the sum of three or more input values. The sum of the electrical signals generated by the adder circuit 32B is output to the outside via an output cable 40.

[0069] In the rope tester 1B of this embodiment, only one electrical signal generated by the addition circuit 32B is output, and therefore the rope tester 1B is required to have only one output cable 40. Note that, since the rope tester 1B outputs the sum of the electrical signals converted by the conversion circuits 34A to 34J, it is not possible to detect which of the five ropes 50 has a wire breakage, but it is possible to detect that at least one of the five ropes 50 has a wire breakage.

[0070] As described above, the rope tester 1C in this embodiment includes a pair of permanent magnets 12 provided in each of the front heads 10A to 10E, which magnetize the five ropes 50, and a first detection coil 13 and a second detection coil 22 provided in each of the front heads 10A to 10E, which generate electrical signals for each of the five ropes 50. This makes it possible to detect a wire break in at least one of the five ropes 50 in a single process. Therefore, the inspection process time can be shortened compared to when each rope 50 is processed individually.

[0071] Furthermore, the rope tester 1C detects magnetic flux from the first detection coil 13 and the second detection coil 22 from opposite directions for each of the five ropes 50, and generates two electric signals for each of the five ropes 50. This makes it possible to more reliably detect damage to the wires in each of the ropes 50 compared to using the results of magnetic flux detection from a single direction.

[0072] Note that a rope tester according to one embodiment of the present invention may be configured without rear heads 20A-20E, conversion circuits 34B, 34D, 34F, 34H, and 34J. In this case, adder circuit 32B may output the sum of electrical signals converted by conversion circuits 34A, 34C, 34E, 34G, and 34I from electrical signals generated by first detection coils 13 of front heads 10A-10E. Even in this case, a single process can detect a wire break in at least one of five ropes 50. This reduces the inspection process time compared to a process performed on each individual rope 50.

[0073] Although the rope tester 1C of this embodiment is configured to detect leakage magnetic flux from two directions for each rope 50 using the first detection coil 13 and the second detection coil 22, the rope tester of the present invention is not limited to this. A rope tester of one aspect of the present invention may be configured to provide three or more detection coils around the rope 50 and detect leakage magnetic flux from three or more mutually different directions.

[0074] Furthermore, although the rope tester 1C of this embodiment is configured to test five ropes 50, the present invention is not limited to this. The rope tester of one aspect of this embodiment may be configured to test a plurality of ropes 50 other than five.

[0075] <Modification> The rope tester 1C in the third embodiment is configured such that the sum of the electrical signals converted by the conversion circuits 34A to 34J is generated by the adder circuit 32B, that is, the sum of all the electrical signals for the five ropes 50 is output. In contrast, the rope tester 1D in this modification outputs the sum of the electrical signals for each of the five ropes. The rope tester 1D will be described in detail below.

[0076] Fig. 17 is a diagram conceptually showing the processing of electrical signals in a rope tester 1D. As shown in Fig. 17, the rope tester 1D includes a circuit box 30D instead of the circuit box 30C in the third embodiment. Furthermore, the rope tester 1D includes output cables 40A to 40E instead of the output cable 40 in the third embodiment.

[0077] The circuit box 30D includes adder circuits 35A to 35E instead of the adder circuit 32B in the third embodiment. The adder circuits 35A to 35E include the same circuit as the adder circuit 32A in the first embodiment, and output the sum of two electrical signals. The electrical signals output from the conversion circuits 34A and 34B are input to the adder circuit 35A, and the sum of the two input electrical signals is output from the adder circuit 35A. The sum of the electrical signals output from the adder circuit 35A is output to the outside via an output cable 40A.

[0078] The electrical signals output from conversion circuits 34C and 34D are input to addition circuit 35B, and the sum of the two input electrical signals is output from addition circuit 35B. The sum of the electrical signals output from addition circuit 35B is output to the outside via output cable 40B.

[0079] The electrical signals output from the conversion circuits 34E and 34F are input to the addition circuit 35C, and the sum of the two input electrical signals is output from the addition circuit 35C. The sum of the electrical signals output from the addition circuit 35C is output to the outside via the output cable 40C.

[0080] The electrical signals output from the conversion circuits 34G and 34H are input to the addition circuit 35D, and the sum of the two input electrical signals is output from the addition circuit 35D. The sum of the electrical signals output from the addition circuit 35D is output to the outside via the output cable 40D.

[0081] The electrical signals output from the conversion circuits 34I and 34J are input to the addition circuit 35E, and the sum of the two input electrical signals is output from the addition circuit 35E. The sum of the electrical signals output from the addition circuit 35E is output to the outside via the output cable 40E.

[0082] As described above, the rope tester 1D of this modified example outputs the sum of electrical signals obtained by converting the electrical signals generated by the corresponding first detection coil 13 and second detection coil 22 into signals containing only positive values ​​for each of the five ropes 50. This allows the rope tester 1D to output the sum of electrical signals for each of the five ropes, making it possible to detect the occurrence of wire breaks in each of the ropes 50 using an external information processing device. Furthermore, in the rope tester 1D, magnetic flux is detected from two directions for each rope 50 by the first detection coil 13 and the second detection coil 22, so damage to the wires in the rope 50 can be detected more reliably.

[0083] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Explanation of symbols]

[0084] 1A, 1B, 1C, 1D Rope Tester 12 Permanent magnet (magnetization part) 13 First detection coil (detection unit) 22 Second detection coil (detection section) 31A, 31C First conversion circuit (conversion section) 31B, 31D Second conversion circuit (conversion unit) 34A~34J Conversion circuit (conversion section) 40, 40A, 40B, 40C, 40D, 40E Output cable (output section) 50 Rope

Claims

1. a magnetizing unit that magnetizes the rope; a detection unit including a plurality of detection elements that detect magnetic flux leaking from the rope magnetized by the magnetization unit and generate an electric signal based on the detection result; a conversion unit that converts each of the plurality of electrical signals generated by each of the plurality of detection elements so that signal values ​​included in the electrical signals are only positive values ​​or only negative values; An output unit that outputs the sum of the multiple electrical signals converted by the conversion unit to the outside.

2. The detection unit detects the magnetic flux by the detection element from a plurality of directions with respect to one rope, and generates a plurality of the electric signals with respect to one rope, The rope tester according to claim 1 , wherein the output unit outputs a sum of the plurality of electrical signals generated for one rope.

3. The magnetizing unit magnetizes the plurality of ropes, The rope tester according to claim 1 , wherein the detection unit includes at least one detection element for each of the plurality of ropes.

4. The rope tester according to claim 3, wherein the detection unit detects the magnetic flux using the detection elements from a plurality of directions for each of the plurality of ropes, and generates a plurality of the electrical signals for each of the plurality of ropes.

5. The rope tester according to claim 1 , wherein the conversion unit converts the signal values ​​to be only positive values ​​or only negative values ​​using an analog electrical circuit.

6. The rope tester according to claim 1 , wherein the conversion unit converts the signal value into an absolute value.

7. The rope tester according to claim 1 , wherein the conversion unit converts the signal value into a squared value.

8. The rope tester according to claim 1 , wherein the conversion unit converts the signal value of a negative value to 0 or converts the signal value of a positive value to 0.

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