Vibration inspection apparatus

Abstract

To provide a vibration inspection apparatus capable of increasing detection sensitivity of reflected waves.SOLUTION: A vibration inspection apparatus comprises: an impact-side roller that is in contact with a target surface of an inspection target object and can roll; an impact mechanism that applies an impact to the target surface via the impact-side roller; a control unit that controls intensity of the impact by the impact mechanism; a reception-side roller that is in contact with the target surface and can roll; a vibration sensor that is provided on the reception-side roller to detect reflected waves from the inspection target object and output a detection signal; a measurement unit that measures intensity of the reflected waves on the basis of the detection signal; and a holding frame that holds the impact-side roller and the reception-side roller.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vibration inspection device. [Background technology]

[0002] In order to inspect the internal condition of an object to be inspected, an inspection device is used that strikes the object to be inspected, measures the vibrations, and evaluates any defects or the like inside the object to be inspected (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-152983 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned device, the vibration sensor is attached at a location distant from the object to be inspected, and therefore the detection sensitivity of the reflected wave may be insufficient.

[0005] An object of one aspect of the present invention is to provide a vibration inspection device that can improve the detection sensitivity of reflected waves. [Means for solving the problem]

[0006] (1) A vibration inspection device according to a first aspect of the present invention comprises an impact roller capable of rolling in contact with a target surface of an object to be inspected, an impact mechanism that applies an impact to the target surface via the impact roller, a control unit that controls the strength of the impact by the impact mechanism, a receiving roller capable of rolling in contact with the target surface, a vibration sensor provided on the receiving roller that detects reflected waves from the object to be inspected and outputs a detection signal, a measurement unit that measures the strength of the reflected waves based on the detection signal, and a holding frame that holds the impact roller and the receiving roller.

[0007] (2) A second aspect of the present invention is a vibration inspection device according to the first aspect, further comprising a microphone for detecting vibrations caused by the impact on the target surface.

[0008] (3) A third aspect of the present invention is the vibration inspection device of the first or second aspect, wherein the holding frame includes a main frame that holds the striking side roller and the receiving side roller so that their rotation axes are parallel to each other.

[0009] (4) Aspect 4 of the present invention is a vibration inspection device according to any one of aspects 1 to 3, wherein the holding frame is provided with an extension frame that supports the impact mechanism so as to apply the impact in a direction perpendicular to the alignment direction of the impact side roller and the receiving side roller.

[0010] (5) A fifth aspect of the present invention is a vibration inspection device according to any one of the first to fourth aspects, wherein a plurality of the vibration sensors are provided, and the plurality of vibration sensors are provided at different positions around the receiving roller.

[0011] (6) A sixth aspect of the present invention is directed to the vibration inspection device of the fifth aspect, wherein a plurality of the vibration sensors are provided and the plurality of vibration sensors are arranged in a circular ring shape in the circumferential direction of the receiving roller. [Effects of the Invention]

[0012] One aspect of the present invention provides a vibration inspection device that can improve the detection sensitivity of reflected waves. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic configuration diagram of a vibration inspection device according to an embodiment. [Figure 2] FIG. 2 is a configuration diagram of a receiving roller of the vibration inspection device according to the embodiment. [Figure 3] FIG. 1 is a front view of a vibration inspection device according to an embodiment. [Figure 4] 1 is a perspective view of a vibration inspection device according to an embodiment. [Figure 5]FIG. 1 is a diagram showing a first usage mode of a vibration inspection device according to an embodiment. [Figure 6] FIG. 10 is a diagram showing a second usage mode of the vibration inspection device according to the embodiment. [Figure 7] FIG. 10 is a diagram showing a third usage mode of the vibration inspection device according to the embodiment. [Figure 8] FIG. 2 is a schematic perspective view showing a first example of a roller. [Figure 9] FIG. 10 is a schematic perspective view showing a second example of the roller. [Figure 10] FIG. 10 is a schematic perspective view showing a third example of the roller. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, a vibration inspection device according to an embodiment of the present invention will be described with reference to the drawings.

[0015] [Vibration inspection equipment] Fig. 1 is a schematic diagram of a vibration inspection device 100 according to an embodiment. Fig. 2 is a diagram of a receiving roller 4. Fig. 3 is a front view of the vibration inspection device 100. Fig. 4 is a perspective view of the vibration inspection device 100.

[0016] As shown in FIG. 1, the vibration inspection device 100 includes a striking roller 1, a striking mechanism 2, a control unit 3, a receiving roller 4, a plurality of vibration sensors 5, a measuring unit 6, a holding frame 7 (see FIG. 3), a microphone 8, an operation unit 9 (see FIG. 3), and a contact terminal 10.

[0017] The striking side roller 1 comes into contact with the target surface 101a of the inspection object 101. The striking side roller 1 transmits the impact from the striking mechanism 2 to the target surface 101a. The striking side roller 1 is rotatably supported by a holding frame 7 (see FIG. 3). The striking side roller 1 is capable of rolling in contact with the target surface 101a.

[0018] The impact mechanism 2 applies an impact to the target surface 101a via the impact side roller 1. The impact mechanism 2 is, for example, an impact device that employs an electromagnetic solenoid. The impact mechanism 2 includes an electromagnetic solenoid section 21, a plunger 22, and a hammer 23. The electromagnetic solenoid section 21 has a cylindrical section 24 that incorporates an electromagnetic coil. At least a portion of the plunger 22 is made of a magnetic material (for example, a metal such as iron). The plunger 22 is inserted into the cylindrical section 24. The plunger 22 can move back and forth in the axial direction relative to the cylindrical section 24. The hammer 23 is attached to the tip (lower end) of the plunger 22. The hammer 23 is made of, for example, metal.

[0019] When the electromagnetic coil of the electromagnetic solenoid portion 21 is energized, the plunger 22 moves by electromagnetic force along the axial direction of the cylindrical portion 24 in a direction approaching the striking roller 1. As a result, the hammer 23 strikes the striking roller 1.

[0020] The control unit 3 outputs a control signal for controlling the operation of the striking mechanism 2. The control unit 3 can control the strength of the strike that the striking mechanism 2 applies to the striking roller 1.

[0021] As shown in Fig. 2, the receiving roller 4 comes into contact with the target surface 101a of the inspection object 101. The receiving roller 4 is rotatably supported by a holding frame 7 (see Fig. 3). The receiving roller 4 is capable of rolling in contact with the target surface 101a. The vibration inspection device 100 can be moved along the target surface 101a by the impact side roller 1 and the receiving side roller 4.

[0022] The vibration sensor 5 is provided on the receiving roller 4. The vibration sensor 5 detects reflected waves from the inspection object 101. The vibration sensor 5 detects the reflected waves and outputs a detection signal. The vibration sensor 5 is, for example, a piezoelectric element or an acceleration sensor. The multiple vibration sensors 5 are provided at positions spaced apart radially outward from the center of the receiving roller 4. The multiple vibration sensors 5 are provided at different positions around the circumference of the receiving roller 4.

[0023] The plurality of vibration sensors 5 are arranged in an annular shape in the circumferential direction of the receiving roller 4. The plurality of vibration sensors 5 are arranged in the circumferential direction of the receiving roller 4 at equal intervals.

[0024] The receiving roller 4 is provided with a plurality of inner circumference electrodes 15 and an outer circumference electrode 16. The inner circumference electrodes 15 are disposed on the inner circumference side of the vibration sensor 5. The inner circumference electrodes 15 are electrically connected to the vibration sensor 5. The plurality of inner circumference electrodes 15 are provided corresponding to the respective vibration sensors 5.

[0025] The outer circumferential electrode 16 is disposed on the outer circumferential side of the vibration sensor 5. The outer circumferential electrode 16 is electrically connected to the vibration sensor 5. The outer circumferential electrode 16 functions as an electrode common to the multiple vibration sensors 5. The outer circumferential electrode 16 is formed in an annular shape along the circumferential direction of the receiving roller 4.

[0026] It is desirable that the inner circumference side electrode 15 and the outer circumference side electrode 16 are electrically connected to the vibration sensor 5, but they do not necessarily have to be electrically connected to the vibration sensor 5. When an electric field is generated in the vibration sensor 5 due to distortion, this electric field may cause a potential difference between the inner circumference side electrode 15 and the outer circumference side electrode 16. Therefore, it may be possible to detect a signal from the vibration sensor 5 even if the electrodes 15, 16 and the vibration sensor 5 are not electrically connected. The electrodes 15, 16 and the vibration sensor 5 may be fixed with an insulating adhesive or the like.

[0027] The contact terminal 10 is provided on the receiving roller 4. The contact terminal 10 extends radially outward from the center of the receiving roller 4. The tip of the contact terminal 10 comes into contact with the inner electrode 15 of a specific vibration sensor 5 among the multiple vibration sensors 5, thereby being electrically connected to that vibration sensor 5.

[0028] The contact terminal 10 can maintain a predetermined posture. In the example shown in FIG. 2, the contact terminal 10 faces downward. Therefore, the contact terminal 10 is electrically connected to the inner electrode 15 of the vibration sensor 5 located at the bottom of the receiving roller 4. In this example, the receiving roller 4 contacts the target surface 101a at its bottom, so the contact terminal 10 is electrically connected to the vibration sensor 5 located at a position where it can detect the reflected wave from the target surface 101a. The contact terminal 10 can send the detection signal obtained from the vibration sensor 5 to the measurement unit 6.

[0029] The measuring unit 6 can measure the intensity of the reflected wave based on the detection signal obtained from the vibration sensor 5. The measuring unit 6 may be configured to automatically save the measurement data.

[0030] As shown in FIGS. 3 and 4, the holding frame 7 has a main frame 31 and an extension frame 32. The main frame 31 is formed in a straight line. The pair of main frames 31 are arranged parallel to each other with a gap between them. One end (first support portion 33) of the pair of main frames 31 rotatably supports the end of the rotating shaft 1A of the striking side roller 1. The other end (second support portion 34) of the pair of main frames 31 rotatably supports the end of the rotating shaft 4A of the receiving side roller 4.

[0031] The pair of main frames 31 are arranged in parallel, and therefore hold the striking side roller 1 and the receiving side roller 4 so that the rotation axis 1A and the rotation axis 4A are parallel to each other.

[0032] The main frame 31 integrally holds the striking side roller 1 and the receiving side roller 4. That is, the main frame 31 holds both the striking side roller 1 and the receiving side roller 4. In this embodiment, the main frame 31 holds the striking side roller 1 and the receiving side roller 4 in an orientation in which their rotation axes are parallel, but "holding the striking side roller and the receiving side roller integrally" also includes cases in which the rotation axes 1A, 4A of the two rollers 1, 4 are not parallel.

[0033] The extension frame 32 includes a pair of extension portions 35, a main connection portion 36, and a connection support portion 37. The pair of extension portions 35 each extend from one end of the pair of main frames 31 as a base end in a direction intersecting with the main frames 31. The pair of extension portions 35 are formed linearly. The extension portions 35 extend, for example, in a direction perpendicular to the main frames 31.

[0034] The main connecting portion 36 connects the tips of the pair of extension portions 35. The connecting support portion 37 spans the pair of extension portions 35 and supports the striking mechanism 2. The striking mechanism 2 is installed so that the movement direction of the plunger 22 is parallel to the extension direction of the extension portions 35. Therefore, the extension frame 32 supports the striking mechanism 2 so that the plunger 22 moves in a direction perpendicular to the main frame 31. In other words, the extension frame 32 supports the striking mechanism 2 so that the plunger 22 moves in a direction perpendicular to the arrangement direction of the striking side roller 1 and the receiving side roller.

[0035] The microphone 8 is an acoustic sensor that detects vibrations caused by an impact on the target surface 101a. The microphone 8 is provided, for example, on the extension portion 35 of the extension frame 32. The microphone 8 detects, for example, audible sounds. The microphone 8 outputs a detection signal based on the detected vibrations.

[0036] The operation unit 9 includes a pair of support frames 39, an intermediate connecting portion 40, an extension portion 41, and a grip portion . The pair of support frames 39 are arranged in parallel with a gap therebetween. Each support frame 39 is rotatably connected to a rotation support portion 43 provided at the middle portion of the main frame 31 in the longitudinal direction.

[0037] The intermediate connecting portion 40 connects the tips of the pair of support frames 39. The intermediate connecting portion 40 is, for example, perpendicular to the support frames 39. The extending portion 41 extends from the center of the intermediate connecting portion 40. The extending portion 41 is, for example, parallel to the support frames 39. The gripping portion 42 is provided in a portion including the tip of the extending portion 41. The gripping portion 42 is, for example, a non-slip cover member made of soft resin or the like.

[0038] [How to use the vibration inspection device] An example of how to use the vibration inspection device 100 will now be described. The vibration inspection device 100 inspects an inspection object 101. The inspection object 101 is, for example, a concrete structure. Examples of concrete structures include tunnels and bridges.

[0039] The vibration inspection device 100 can inspect, for example, defects in concrete structures. The vibration inspection device 100 can evaluate, for example, cracks inside concrete and the degree of filling of concrete injection materials. Cracks can be caused by, for example, static external forces, fatigue, expansion pressure due to corrosion of rebars, etc. after the construction of the concrete structure. Cracks can also be caused by poor construction work during the construction of the concrete structure.

[0040] As shown in Fig. 3, the striking roller 1 and receiving roller 4 of the vibration inspection device 100 are brought into contact with the target surface 101a of the object 101 to be inspected. In Fig. 3, the target surface 101a is a horizontal plane. The support frame 39 of the operation unit 9 is oriented perpendicular to the main frame 31. As shown in Fig. 2, the contact terminal 10 is electrically connected to the vibration sensor 5 located at a position (lowest position) where it can detect the reflected wave from the target surface 101a.

[0041] In the impact mechanism 2, when the electromagnetic coil of the electromagnetic solenoid unit 21 is energized, the plunger 22 moves by electromagnetic force along the axial direction of the cylindrical unit 24 in a direction approaching the impact side roller 1. As a result, the hammer 23 strikes the target surface 101a via the impact side roller 1.

[0042] The striking mechanism 2 is installed so that the direction of movement of the plunger 22 is parallel to the extension portion 35 of the extension frame 32 , and therefore the plunger 22 moves in a direction perpendicular to the main frame 31 .

[0043] When an impact is applied to the target surface 101a, the vibration propagates into the object under test 101 and is reflected by the bottom or other part of the object under test 101, generating a reflected wave. If there is a defect such as a crack inside the object under test 101, a reflected wave will also be generated from this defect.

[0044] The vibration sensor 5 provided on the receiving roller 4 detects the reflected wave from the inspection object 101. The vibration sensor 5 can detect not only the reflected wave from the bottom of the inspection object 101 but also the reflected wave from a defect at a shallow position. The vibration sensor 5 outputs a detection signal based on the reflected wave. The measurement unit 6 can measure the intensity of the reflected wave, etc. based on the detection signal.

[0045] The user can ascertain the presence or absence, position, etc. of defects in the inspection object 101 based on the measurement data obtained by the measurement unit 6. The user can determine the presence or absence of defects based on, for example, the propagation speed and propagation time of the reflected wave. The user can also estimate the position of the defect based on the propagation speed and propagation time of the reflected wave.

[0046] If there is a void near the surface of the inspection target 101, the part that has been peeled off by the void may vibrate when struck. This vibration is reflected in the vibration when a strike is applied to the target surface 101a.

[0047] The microphone 8 detects vibrations caused by striking the target surface 101a and outputs a detection signal based on the vibrations. The measurement unit 6 can determine the presence or absence, position, etc. of defects in the surface layer of the inspection target 101 based on the detection signal from the microphone 8. The measurement unit 6 can, for example, analyze the frequency of the vibrations and determine the presence or absence, position, etc. of defects in the surface layer of the inspection target 101 based on the sound pressure level of a specific frequency.

[0048] 5 to 7 are diagrams showing other modes of use of the vibration inspection device 100. In FIG. 5 shows a first usage mode of the vibration inspection device 100. As shown in Fig. 5, the target surface 101a may be a horizontal top surface. The support frame 39 of the operation unit 9 is oriented perpendicular to the main frame 31.

[0049] Fig. 6 shows a second usage mode of the vibration inspection device 100. As shown in Fig. 6, the target surface 101a may be an inclined surface inclined relative to the horizontal. The support frame 39 of the operation unit 9 is inclined toward the extension frame 32 with respect to the main frame 31.

[0050] Fig. 7 shows a third usage mode of the vibration inspection device 100. As shown in Fig. 7, the target surface 101a may be an inclined surface oriented in a different direction from that shown in Fig. 6. The support frame 39 of the operation unit 9 is inclined relative to the main frame 31 in a direction away from the extension frame 32.

[0051] As shown in FIGS. 3 and 5 to 7, the vibration inspection device 100 is capable of inspection regardless of the orientation of the target surface 101a.

[0052] Fig. 8 is a schematic perspective view showing a roller 201, which is a first example of the roller, and Fig. 9 is a schematic perspective view showing a roller 202, which is a second example of the roller.

[0053] The roller 201 shown in FIG. 8 has a relatively small ratio (L1 / D) of the length L1 to the outer diameter D. When the roller 201 is used, the vibration inspection device can be made smaller and lighter. The roller 202 shown in FIG. 9 has a relatively large ratio (L2 / D) of the length L2 to the outer diameter D. When the roller 202 is used, a wide range can be inspected, thereby reducing the number of work steps. The rollers 201 and 202 shown in FIGS. 8 and 9 may be used as striking rollers or receiving rollers.

[0054] FIG. 10 is a schematic perspective view showing roller 203, a third example of a roller. Roller 203 shown in FIG. 10 can be used as a striking roller. A plurality of protrusions 204 are formed on the outer peripheral surface of roller 203. Protrusions 204 are formed along the length direction of roller 203. The plurality of protrusions 204 are formed at intervals in the circumferential direction of roller 203. It is desirable that the plurality of protrusions 204 be formed at equal intervals (or at equal pitch) in the circumferential direction of roller 203.

[0055] The roller 203 has a protrusion 204, which can strike the target surface 101a at regular intervals. This makes it easier to detect defects in the surface layer of the inspection target 101.

[0056] [Effects of the vibration inspection device according to the embodiment] The vibration inspection device 100 includes a receiving roller 4 equipped with a vibration sensor 5, so that the reflected waves from the target surface 101a can be directly detected by the receiving roller 4. This improves the detection sensitivity of the reflected waves compared to when the reflected waves are detected via a striking roller.

[0057] The vibration inspection device 100 is equipped with a microphone 8 that detects vibrations caused by impact, and is therefore able to detect defects in the surface layer of the inspection object 101 by vibrations, thereby enabling highly accurate inspection.

[0058] The holding frame 7 includes a main frame 31 that holds the striking roller 1 and the receiving roller 4 so that the rotation axes 1A, 4A are parallel to each other, so that the striking roller 1 and the receiving roller 4 can be brought into uniform contact with the target surface 101a in a stable posture. This reduces the variation in the striking force that the striking mechanism 2 applies to the inspection target 101.

[0059] The holding frame 7 includes an extension frame 32 that supports the striking mechanism 2 so that the striking mechanism 2 strikes the striking roller 1 in a direction perpendicular to the alignment direction of the striking roller 1 and the receiving roller 4, so that the striking direction of the striking roller 1 can be kept constant, thereby improving the accuracy of the inspection.

[0060] The vibration sensors 5 are provided at different positions around the circumference of the receiving roller 4, so that reflected waves can be detected with high precision even when the receiving roller 4 is rolling. The vibration sensors 5 are arranged in a circular pattern in the circumferential direction of the receiving roller 4, so that the reflected waves can be detected with high precision.

[0061] The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. In Figure 2, it is desirable that all of the multiple vibration sensors 5 are arranged at different positions around the circumference of the receiving roller 4, but it is sufficient that two or more of the multiple vibration sensors 5 are arranged at different positions around the circumference of the receiving roller 4. As shown in FIG. 2, the vibration inspection device 100 includes multiple vibration sensors 5, but the number of vibration sensors may be one. In this case, the vibration sensor is formed, for example, in a circular ring shape along the circumferential direction of the receiving roller. The vibration sensor may be a sheet-type sensor. The number of vibration sensors may be one or more.

[0062] In addition, it is possible to replace the components in the above-described embodiments with well-known components as appropriate, and the above-described embodiments and variations may be combined as appropriate, without departing from the spirit of the present invention. [Explanation of symbols]

[0063] 1...Impact roller 1A...Rotating shaft 2...Striking mechanism 3...Control unit 4...Receiving roller 4A...Rotating shaft 5...Vibration sensor 6...Measuring section 7...Holding frame 8. Mike 31...Main frame 32...Extended frame 100...Vibration inspection device 101...Inspection object 101a...Target surface

Claims

1. an impact roller that can roll in contact with the target surface of the object to be inspected; a striking mechanism that strikes the target surface via the striking roller; a control unit that controls the strength of the impact by the impact mechanism; a receiving roller capable of rolling in contact with the target surface; a vibration sensor provided on the receiving roller for detecting a reflected wave from the object to be inspected and outputting a detection signal; a measuring unit that measures the intensity of the reflected wave based on the detection signal; a holding frame for holding the striking roller and the receiving roller; Equipped with Vibration testing equipment.

2. Further, a microphone is provided to detect vibrations caused by the impact on the target surface. The vibration inspection device according to claim 1.

3. The holding frame includes a main frame that holds the striking side roller and the receiving side roller so that their rotation axes are parallel to each other. The vibration inspection device according to claim 1.

4. the holding frame includes an extension frame that supports the striking mechanism so as to apply the striking in a direction perpendicular to the alignment direction of the striking-side roller and the receiving-side roller. The vibration inspection device according to claim 1.

5. The vibration sensor is provided in plurality, The plurality of vibration sensors are provided at different positions in the circumferential direction of the receiving roller. The vibration inspection device according to claim 1.

6. The vibration sensor is provided in plurality, The plurality of vibration sensors are arranged in an annular shape in the circumferential direction of the receiving roller.

6. The vibration inspection device according to claim 5.

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