JP2019066322A - Inspection device and cable with inspection device - Google Patents

Abstract

To provide an inspection device and a cable with the inspection device with which it is possible to detect damage in the cable with high accuracy.SOLUTION: An inspection device 30 detects damage in a cable 20 using the vibration transmitted to a second end part 20b when a first end part 20a of the cable 20 is vibrated in a direction X. The inspection device comprises: a vibration unit 40 for vibrating the first end part 20a of the cable 20 while sweeping a vibration frequency; a vibration conversion unit 50 for converting the vibration transmitted to the second end part 20b when the first end part 20a of the cable 20 vibrates by vibration of the vibration unit 40 into a signal; and an inspection unit 62 for detecting damage in the cable 20 using the signal outputted by the vibration conversion unit 50. The inspection unit 62 detects damage in the cable 20 on the basis of the magnitude of the signal voltage outputted from the vibration conversion unit 50 when the first end part 20a of the cable 20 is vibrated by the vibration unit 40 while sweeping the vibration frequency.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an inspection device that detects damage to a cable, and a cable with the inspection device.

  In general, various cables are used for transmission / reception of control signals and power supply, and disconnection of these cables may lead to troubles such as breakdown of equipment. For this reason, in the case of a cable or the like installed in a place where it is easy to break or important equipment, preventive measures such as preventing the break in advance are taken by setting the usage period of the cable shorter than usual. There are also many things.

  By the way, there has also been proposed an inspection method for inspecting the presence or absence of cable damage using acoustics such as acoustic emission generated when the cable is vibrated.

  For example, in Patent Document 1, when an impact is applied to one end of a cable with a hammer or the like, a vibration waveform transmitted to the other end of the cable is measured by an accelerometer such as an AE sensor, and disconnection is detected based on the measured vibration waveform. A cable inspection method for detecting presence or absence is disclosed.

JP-A-8-130811

  However, in the inspection method described in Patent Document 1 described above, it is necessary to use a hammer to strike a cable, but when a hammer is used, the striking force (that is, the excitation force) varies among workers. It occurs. This variation in the excitation force causes the transmission of vibration to the cable to be different, which causes a problem that it is difficult to detect damage to the cable with high accuracy.

  An object of this invention is to provide the inspection apparatus which can detect the damage of a cable accurately, and the cable with an inspection apparatus.

  The inspection device according to the present invention is a cable inspection device that detects cable damage using vibration transmitted to the second end of the cable when the first end of the cable is axially vibrated. An excitation unit that excites the first end of the cable while sweeping a frequency, and an excitation transmitted to the second end when the first end of the cable vibrates due to the excitation of the excitation unit. The vibration conversion unit, and the inspection unit that detects damage to the cable using a signal output from the vibration conversion unit, and the inspection unit vibrates the cable while sweeping the vibration frequency by the excitation unit. The cable damage is detected based on the magnitude of the voltage of the signal output from the vibration converter. Here, damage to the cable means damage that may lead to disconnection of the cable.

  In the inspection apparatus of the present invention, the inspection unit stores, as reference data, a signal output from the vibration conversion unit when the excitation unit sweeps the vibration frequency while the first end of the cable is excited for the first time. Of the cable by comparing the signal obtained by the vibration excitation unit vibrating the first end of the cable after the second time with the reference data stored in the storage unit. It may be detected.

  In the inspection apparatus according to the present invention, the inspection unit is a multi-core cable including a first core wire and a second core wire, and the inspection unit is a first end of the cable while the vibration unit sweeps the vibration frequency. Damage to the first core wire based on whether the difference between the signal voltage of the first core wire output from the vibration conversion unit and the signal voltage of the second core wire is greater than a predetermined reference value when excited. It may be detected.

  Further, in the inspection device of the present invention, the excitation unit fixes the diaphragm and the pressure plate in a state in which the diaphragm is vibrated by the magnetic force of the electromagnet, the pressure plate that presses the cable against the vibration plate, and the cable. The stationary block may include a substrate that supports the stationary block so as to be able to swing in the vibration direction of the diaphragm.

  A cable with a check device according to the present invention comprises the check device according to any of the above inventions, and a cable having a vibration excitation unit attached to a first end and a vibration conversion unit attached to a second end. It may be something.

  According to the inspection device of the present invention, when the first end of the cable is vibrated while sweeping the vibration frequency, the vibration transmitted to the opposite second end is converted into a signal, and based on the voltage of this signal Detect cable damage. Here, the amplitude of the vibration transmitted to the second end is smaller in the case where the cable is damaged than in the case where the cable is not damaged, and the signal voltage output from the vibration conversion unit is also reduced accordingly. For this reason, when the first end of the cable is vibrated while sweeping the vibration frequency at a vibration frequency of a predetermined range, the cable damage may be caused depending on whether the signal voltage output from the vibration conversion unit is entirely reduced. The presence or absence can be detected accurately.

  According to the cable with inspection device of the present invention, when the first end of the cable is oscillated while sweeping the vibration frequency, the vibration transmitted to the opposite second end is converted into a signal, and the voltage of this signal is converted to a signal. Based on the detection of cable damage. Here, the amplitude of the vibration transmitted to the second end is smaller in the case where the cable is damaged than in the case where the cable is not damaged, and the signal voltage output from the vibration conversion unit is also reduced accordingly. For this reason, when the first end of the cable is vibrated while sweeping the vibration frequency at a vibration frequency of a predetermined range, the cable damage may be caused depending on whether the signal voltage output from the vibration conversion unit is entirely reduced. The presence or absence can be detected accurately.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram of the cable with a test | inspection apparatus which is one Embodiment of this invention. Fig.2 (a) is a disassembled perspective view of the vibration excitation part contained in FIG. FIG.2 (b) and FIG.2 (c) are figures explaining operation | movement of a vibration excitation part using sectional drawing when it cut | disconnects along the AA shown to the figure (a). Fig.3 (a) is a disassembled perspective view of the vibration conversion part contained in FIG. FIG. 3B is a side view of the vibration converter when viewed from the direction B included in FIG. FIG. 4A is a diagram showing the vibration frequency applied while sweeping the cable core wire by the vibration excitation unit. FIG.4 (b) is a figure which shows the relationship between the vibration frequency and signal voltage which a vibration conversion part outputs, when the vibration frequency shown to the figure (a) is added to a cable core wire. It is a flowchart which shows the flow of the inspection process in the control part contained in FIG. It is a figure which shows the modification of the cable with an inspection apparatus.

  An inspection apparatus-equipped cable according to an embodiment of the present invention will be described with reference to the drawings. In the following description, “X direction” indicates a direction parallel to the longitudinal (axis) direction of the cable, and “Y direction” indicates the thickness direction of each substrate of the excitation unit and the vibration conversion unit described later. The "Z direction" indicates a direction orthogonal to the X direction and the Y direction. As shown in FIGS. 1 and 2, the inspection apparatus cable 10 includes a cable 20 and an inspection apparatus 30 that inspects the cable 20 for damage. The cable 20 is used, for example, for transmission / reception of control signals and power supply in industrial equipment such as a robot arm, and is a multi-core cable including first to fourth core wires 22, 24, 26, 28. . Here, the damage of the cable 20 means the damage which leads to the disconnection of the cable 20. More specifically, it means, for example, a damage that entails an increase in internal resistance in the coaxial wire 22 even if the wire does not lead to breakage due to breakage of a part of the first core wire 22 constituting the cable 20.

  On the other hand, as shown in FIG. 1, the inspection device 30 includes an excitation unit 40 attached to the first end 20 a of the cable 20 and a vibration conversion unit 50 attached to the second end 20 b of the cable 20. Equipped with The vibration unit 40 includes an electromagnet 41, a substrate 42 removably attached to a connector (not shown), and a vibration unit 43 pivotally attached to the substrate 42. The substrate 42 has four strip electrodes 42a, 42b, 42c, 42d formed on the surface, and is electrically connected to a connector (not shown) via the electrodes. Further, as shown in FIGS. 2 (b) and 2 (c), a guide hole 42h is provided on one end side in the Z direction on this substrate for attaching a fixing block to be described later.

  Further, as shown in FIG. 2A, the vibration unit 43 includes the plate-like diaphragm 44, the fixing block 45 for fixing the diaphragm 44, and the core wires 22 to 28 between the diaphragm 44 and the diaphragm 44. And a holding plate 46 made of resin for holding the same. The vibrating plate 44 is provided with four electrodes 44a, 44b, 44c and 44d having a substantially rectangular appearance at regular intervals along the longitudinal direction. The electrodes 44a to 44d of the diaphragm 44 are electrically connected to the strip electrodes 42a to 42d of the substrate 42 through through holes 45a, 45b, 45c, and 45d provided in the fixed block 45. Therefore, the strip electrodes 42 a of the substrate 42 are held by sandwiching the core wires 22-28 between the presser plate 46 and the diaphragm 44 in a state where the core wires 22-28 are in contact with the electrodes 44 a-44 d of the diaphragm 44 respectively. -42d and each core wire 22-28 can be electrically connected. The pressing plate 46 has a substantially L-shaped outer shape, and a thin substantially rectangular iron plate 47 is fixed to the surface facing the electromagnet 41, and sandwiches the core wires 22 to 28 with the diaphragm 44. It is fixed to the fixed block 45 together with the diaphragm 44 with a screw or the like.

  As shown in FIGS. 2 (b) and 2 (c), the fixing block 45 includes a bolt BL1 inserted into a guide hole 42h provided on one end side of the substrate 42 in the Z direction, and a guide on the other end side. It is a resin member attached to the substrate 42 by a bolt inserted into the hole. The configuration of the guide hole and the bolt on the other end side is the same as the guide hole 42 h on the one end side and the bolt BL1. A flat washer 48a and a spring washer 48b are inserted into the bolt BL1 so as to be interposed between the bolt 42 and the base plate 42. The fixing block 45 is pressed against the base plate 42 by the elastic force of the spring washer 48b. On the other hand, the guide hole 42h is formed such that the width dimension in the X direction is slightly larger than the diameter of the shaft portion of the bolt BL1. Therefore, each of the electrodes 44a to 44d of the diaphragm 44 can vibrate in the X direction while maintaining an electrical connection with each of the strip electrodes 42a to 42d (see FIG. 2A) of the substrate 42. The fixed block 45 is held in the state.

  Next, the operation of the excitation unit 40 will be described. As shown to Fig.2 (a), the excitation part 40 reverses direction of the magnetic force which generate | occur | produces by changing the polarity of the voltage applied to the coil (not shown) contained in the electromagnet 41 alternately. As a result, the attraction force for attracting the iron plate 47 of the holding plate 46 and the repulsion force for repulsion are alternately generated, and as shown in FIGS. 2B and 2C, the vibration unit 43 approaches the electromagnet 41 or Move alternately in the direction of separation. Thus, the first end 20 a of each of the core wires 22 to 28 is vibrated by the vibration unit 40.

  FIG. 3A is an exploded perspective view showing a partial configuration of the vibration conversion unit 50 in a disassembled state. The figure (b) is a side view of the vibration conversion part 50 when it sees from the B direction shown in FIG. As shown in FIGS. 3A and 3B, the vibration conversion unit 50 includes a substrate 52 provided with four strip electrodes 52a, 52b, 52c, 52d, and a resin pedestal 54 fixed to the substrate 52. And a presser plate 56 made of resin for pressing and fixing each of the core wires 22 to 28 to the resin pedestal 54. Through holes 54h connected to the strip electrodes 52a to 52d of the substrate 52 are respectively provided in the resin pedestal 54, and the respective core wires 22 to 28 are provided so as to cover the through holes 54h. Piezoelectric elements 58a, 58b, 58c and 58d are respectively installed on .about.28. Thus, with the core wires 22 to 28 and the piezoelectric elements 58 a to 58 d superimposed on the resin pedestal 54, the core wires 22 to 28 and the piezoelectric elements 58 a to 58 d are pressed against the resin pedestal 54 by the pressing plate 56. Fix it. Here, detection electrodes 56a, 56b, 56c and 56d are provided on the holding plate 56 at positions in contact with the piezoelectric elements 58a to 58d when the piezoelectric elements 58a to 58d are pressed and fixed to the resin pedestal 54, respectively. There is. Thereby, when the second ends 20b of the core wires 22-28 vibrate, signal voltages generated in the piezoelectric elements 58a-58d will be described later via signal lines (not shown) connected to the detection electrodes 56a-56d. It can be sent to the control unit. In the present embodiment, the vibration of each core 22 to 28 is converted into a signal using the piezoelectric elements 58a to 58 d, but the vibration of each core 22 to 28 may be converted to a signal using a micro speaker or the like. .

  Here, vibration suppression grooves 54a, 54b, 54c are provided on the resin pedestal 54 between the piezoelectric elements 58a to 58d. In addition, vibration suppression holes 56e, 56f, and 56g having a rectangular shape in top view are also provided between the detection electrodes 56a to 56d in the pressing plate 56. The vibration suppressing grooves 54a to 54c and the vibration suppressing holes 56e to 56g play a role of suppressing the transmission of the vibration of one of the adjacent core wires to the piezoelectric element in contact with the other core via the resin pedestal 54 and the holding plate 56. Have. Thereby, it is possible to prevent the noise derived from the vibration of the one core wire from being mixed in the signal transmitted from each of the piezoelectric elements 58a to 58d. In the present embodiment, both of the vibration suppression grooves 54a to 54c of the resin pedestal 54 and the vibration suppression holes 56e to 56g of the pressing plate 56 are provided, but only one of them may be provided.

  In addition, as shown in FIG. 1, the inspection apparatus-equipped cable 10 includes a control unit 60 that executes an inspection operation of causing the excitation unit 40 to vibrate the first ends 20 a of the core wires 22-28. Here, since the inspection operation for each core wire 22 to 28 is the same, in the following description, only the inspection operation for the first core wire 22 will be described, and the inspection operation for the other core wires 24 to 28 will be omitted Do.

  FIG. 4A is a diagram showing the vibration frequency that the vibration unit 40 applies to the first core wire 22 of the cable 20 while sweeping. FIG. 4B is a diagram showing the relationship between the vibration frequency and the signal voltage output from the vibration conversion unit 50 when the vibration frequency shown in FIG. 4A is applied to the first core wire 22 of the cable 20. As shown in FIG. 4A, the control unit 60 applies the first end 20a of the first core wire 22 to the excitation unit 40 while sweeping the vibration frequency between the lower limit frequency P1 and the upper limit frequency P2. Shake.

  Here, it is preferable that the lower limit frequency P1 and the upper limit frequency P2 satisfy the relationship of 10 Hz ≦ P1 <P2 ≦ 20 kHz and be set so as to include a resonance frequency region in which the core wires 22 to 28 resonate. The resonance frequency region means a region including a peak frequency Pmax where the signal voltage becomes larger than the peripheral frequency due to the resonance of the cable 20 as shown in FIG. 4B. Further, in such a resonant frequency region, the signal waveform W2 in the case where slight damage is observed in a part of the first core wire 22 with respect to the signal waveform W1 in the case where the first core wire 22 is not damaged, As in the signal waveform W3 in the case where the core wire 22 of 1 is almost disconnected, the larger the damage to the first core wire 22, the greater the attenuation of the signal voltage in the region centered on the peak frequency Pmax. For this reason, the presence or absence of the disconnection of the first core wire 22 can be easily detected from the magnitude of the attenuation of the signal voltage in the resonant frequency region. Further, as described above, by exciting the cable 20 while sweeping the vibration frequency, it is possible to obtain a signal output including the peak frequency Pmax at which the cable 20 resonates without examining the natural frequency of the cable 20 in advance. it can. In the present embodiment, only one peak frequency is included in the resonant frequency range, but a plurality of peak frequencies may be included in the resonant frequency range.

  On the other hand, it is also conceivable that the above-mentioned resonance frequency range is not included between the lower limit frequency P1 and the upper limit frequency P2 described above. Even in such a case, the excitation portion 40 adds the first end 20a of the first core wire 22 more in the case where the first core wire 22 is damaged than in the case where the first core wire 22 is not damaged. The vibration transmitted to the second end 20b when being shaken is relatively greatly attenuated. For this reason, the voltage of the signal output from the vibration conversion unit 50 is also relatively greatly attenuated in the case where the first core wire 22 is damaged than in the case where the first core wire 22 is not damaged. Therefore, even when the resonance frequency range is not included between the lower limit frequency P1 and the upper limit frequency P2, the presence or absence of the disconnection of the first core wire 22 is detected based on the magnitude of attenuation of the signal voltage output from the vibration conversion unit 50. It is possible. However, in this case, a large attenuation of the signal voltage is not observed as compared to the above-described resonant frequency range, so it is more preferable to set the resonant frequency range to be included between the lower limit frequency P1 and the upper limit frequency P2. is there.

  In addition, the control unit 60 causes the excitation unit 40 to excite the first end 20 a of the first core wire 22 while sweeping the vibration frequency as shown in FIG. The inspection unit 62 (see FIG. 1) detects damage to the cable 20 based on the magnitude of the voltage of the signal (see FIG. 4B) output from the vibration conversion unit 50 attached to 20b. The inspection unit 62 performs the first inspection operation, that is, the vibration conversion when the excitation unit 40 excites the first end 20 a of the first core wire 22 for the first time with the cable 20 attached to the industrial device. The storage unit 64 stores a signal output from the unit 50 as reference data. Thus, the signal waveform output from the vibration conversion unit 50 at the start of use of the cable 20 can be used as reference data at the time of the second and subsequent inspections. The inspection unit 62 sets a signal (hereinafter referred to as “measurement signal”) output from the vibration conversion unit 50 at the time of the second and subsequent inspection operations as a signal of reference data stored in the storage unit 64. The damage of the cable 20 is detected by comparison.

  More specifically, the inspection unit 62 performs noise removal processing on the measurement signal and then calculates a difference value ΔV between the sum of the signal voltage values of the reference data and the sum of the voltage values of the measurement signal. As a method of this noise removal processing, the voltage value Vr of the reference data signal at the same frequency and the voltage value Vp of the measurement signal are compared, and the voltage value Vp of the measurement signal is higher than the signal voltage value Vr of the reference data. When it becomes large, there is a method of removing noise of the voltage value included in the measurement signal by replacing the voltage value Vp of the measurement signal at the frequency with the voltage value Vr of the reference data. Thereby, for example, the sum of the voltage values of the measurement signals is calculated in a state in which the influence of the vibration frequency in which the voltage value of the measurement signals is increased due to external factors such as resonance of the coating of the cable 20 is eliminated. it can.

  And the inspection part 62 detects the presence or absence of the damage in the 1st core wire 22 based on whether the said difference value (DELTA) V is more than a predetermined reference value. When the inspection unit 62 detects that the first core wire 22 is damaged, the control unit 60 transmits an abnormality signal notifying a cable abnormality to an information terminal 70 (see FIG. 1) or the like that operates the industrial device on which the cable 20 is installed. Do. As a result, for example, a message prompting to replace the cable is displayed on the monitor 72 of the information terminal 70, and the operator is notified of the abnormality of the cable 20. The inspection unit 62 may provide a plurality of predetermined reference values in order to use the difference value ΔV in accordance with the degree of damage to the cable 20. In this case, for example, when the damage to the cable 20 is minor, only the message prompting the replacement of the cable 20 is transmitted as described above to transmit an abnormal signal to be displayed on the monitor 72 of the information terminal 70 and the damage to the cable 20 is large. In this case, the above message may be displayed and an abnormal signal may be transmitted to prevent the start of the industrial device. As a result, it is possible to prevent the cable 20 from being completely disconnected during startup of the industrial device, and the device may be damaged due to the disconnection.

  FIG. 5 is a flow chart for explaining the flow of the inspection process in the cable 10 with an inspection device. As shown in FIG. 5, the control unit 60 starts an inspection operation at a predetermined inspection timing, for example, when the main power of the industrial device in which the cable 20 is installed is switched from the OFF state to the ON state (step S1). . The inspection unit 62 stores the signal output from the vibration conversion unit 50 as reference data in the storage unit 64 when the excitation unit 40 excites the cable 20 in the first inspection operation (see FIG. Steps S2 and S3). On the other hand, the inspection unit 62 compares the signal of reference data stored in the storage unit 64 with the signal output from the vibration conversion unit 50 in the second and subsequent inspection operations, and detects the first core 22. The presence or absence of damage is detected (steps S2 and S4). When the inspection unit 62 detects the damage of the first core wire 22, the control unit 60 transmits an abnormality signal notifying an abnormality of the first core wire 22 to the information terminal 70 (steps S5 and S6). Thereby, the abnormality of the cable 20 is notified to the operator via the information terminal 70.

  According to the inspection apparatus-equipped cable 10 of the present embodiment, when the first end 20 a of the cable 20 is vibrated while sweeping the vibration frequency, the vibration converting unit 50 attached to the opposite second end 20 b Damage to the cable 20 is detected based on the output signal voltage. Here, the amplitude of the vibration transmitted to the second end 20b is smaller in the case where the cable 20 is damaged than in the case where the cable 20 is not damaged, and the signal voltage output from the vibration conversion unit 50 accordingly Also becomes smaller. Therefore, depending on whether or not the signal voltage output from the vibration conversion unit 50 is generally lowered when the vibration is performed while sweeping the first end 20a of the cable 20 at a vibration frequency of a predetermined range. The presence or absence of damage can be accurately determined and detected.

  In the above embodiment, the inspection unit 62 cites an example using the signal output from the vibration conversion unit 50 as reference data when the vibration unit 40 vibrates the first end 20 a of the cable 20 for the first time. However, the present invention is not limited to this. For example, the inspection unit 62 corresponds to both cores 22 and 24 from the vibration conversion unit 50 when the exciter 40 excites each of the first core wire 22 and the second core wire 24 while sweeping the vibration frequency. You may use the signal output by In this case, the sum of the signal voltages output from the vibration conversion unit 50 corresponding to the second core wire 24 is subtracted from the sum of the signal voltages output from the vibration conversion unit 50 corresponding to the first core wire 22. Whether or not the cable 20 is damaged can be detected based on whether or not the difference value is larger than a preset reference value.

  In the above embodiment, the control unit 60 performs the inspection operation by causing the excitation unit 40 to vibrate the first end 20a of the cable 20. However, the excitation unit 40 is used instead of the control unit 60. The control function may be provided to perform the inspection operation at a predetermined inspection timing. Also in this case, the inspection unit 62 can detect whether the cable 20 is damaged or not based on the signal voltage output from the vibration conversion unit 50 when the excitation unit 40 performs the inspection operation at a predetermined inspection timing. .

  FIG. 6 is a view showing a configuration of a cable with inspection device 100 which is a modification of the cable with inspection device 10 in the above embodiment. In the following description, in the inspection apparatus cable 100, parts different in configuration from the inspection apparatus cable 10 of the above embodiment will be mainly described, and parts having the same configuration as the inspection apparatus cable 10 have the same reference numerals. The description is omitted as appropriate. As shown in FIG. 6, the inspection device-equipped cable 100 includes a branch type cable 120, an inspection device 130, and a control unit 60. The branched cable 120 has two second end portions 120b-1 and 120b-2 opposite to the first end portion 120a. In addition, the inspection device 130 is a vibration conversion unit attached to the first end 120 a of the branch cable 120 and a vibration conversion attached to the second ends 120 b-1 and 120 b-2 of the branch cable 120. And units 152 and 154. The vibration converters 152 and 154 each have the same configuration as the vibration converter 50 of the above embodiment. As described above, in the case of the branched cables, the same effects as the inspection apparatus-equipped cable 10 in the above-described embodiment can be obtained by providing the vibration conversion parts at the branched end portions of the cables. In addition, although 2nd end part 120b-1 and 120b-2 branch in the branch type cable 120, the branch type cable to which the opposite 1st end part has branched may be sufficient. As described above, in the case of the branched cable in which the first end side is branched, it is sufficient to respectively provide the excitation portion at a plurality of first ends.

  The present invention can also be carried out in variously modified, modified or modified forms based on the knowledge of those skilled in the art without departing from the spirit of the invention. Moreover, you may implement in the form which substituted any invention specific matter to the other technique in the range to which the same effect | action or effect arises.

10, 100 Cable with Inspection Device 20, 120 Cable 20a, 120a First End 20b, 120b-1, 120b-2 Second End 22, 24, 26, 28 Core Wire 30, 130 Inspection Device 40 Excitation Unit 41 Electromagnet 42, 52 substrate 43 vibration unit 44 diaphragm 46, 56 pressing plate 47 iron plate 50, 152, 154 vibration converting unit 52 substrate 54 resin pedestal 56 pressing plate 60 control unit 62 inspection unit 64 storage unit S1 to S6 step W1 to W3 signal Waveform

Claims (5)

A cable inspection device for detecting damage to a cable by using vibration transmitted to the second end of the cable when the first end of the cable is axially vibrated,
An excitation unit for exciting the first end of the cable while sweeping the vibration frequency;
A vibration conversion unit that converts vibration transmitted to the second end into a signal when the first end of the cable vibrates due to the excitation of the excitation unit;
An inspection unit that detects damage to the cable using the signal output from the vibration conversion unit;
Equipped with
The inspection unit detects damage to the cable based on the magnitude of the voltage of the signal output from the vibration conversion unit when the vibration unit vibrates the cable while sweeping the vibration frequency. Characterized by
Inspection device. The inspection unit stores the signal output from the vibration conversion unit as reference data when the vibration unit sweeps the vibration frequency and vibrates the first end of the cable for the first time And the excitation unit excites the first end of the cable after the second time and the reference data stored in the storage unit are compared with each other. Detect cable damage,
The inspection device according to claim 1. The cable is a multicore cable including a first core wire and a second core wire,
The inspection unit is configured to generate the second core wire from the signal voltage of the first core wire output from the vibration conversion unit when the vibration portion sweeps the vibration frequency and vibrates the first end of the cable. And detecting the damage to the first core wire based on whether or not the difference obtained by subtracting the signal voltage of the second line is greater than a predetermined reference value.
The inspection device according to claim 1. The excitation unit includes: a vibrating plate that vibrates by the magnetic force of an electromagnet; a pressing plate that presses the cable against the vibrating plate; and a fixing block that fixes the vibrating plate and the pressing plate with the cable interposed therebetween. And a substrate swingably supporting the fixed block in the vibration direction of the diaphragm.
The inspection device according to any one of claims 1 to 3. The inspection device according to any one of claims 1 to 4;
The cable in which the excitation unit is attached to the first end, and the vibration converter is attached to the second end;
Cable with inspection device equipped with.

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