Sound wave inspection device, sound wave inspection method, and holder for sound wave inspection device

Abstract

To provide a sound wave inspection device capable of easily moving a contact medium with an object to be inspected in close contact with the contact medium upon inspection, and allowing the contact medium to be easily replaced.SOLUTION: A sound wave inspection device 1 of an embodiment includes: a sound wave probe 2 having a sound wave functional surface; a contact member 10 including a contact medium 8 having a first surface in contact with the sound wave functional surface of the sound wave probe 2 directly or through an intermediate member and a second surface on an opposite side to the first surface, and containing elastomer, and a sheet member 9 laminated on the contact medium 8 in contact with the second surface and containing a polymer and having a plurality of openings; a holder 11 for holding the contact member 10 and attaching it to the sound wave probe 2, and to which a part of the sheet member 9 having the plurality of openings is fixed so that at least the part of the sheet member 9 having the plurality of openings is positioned at the outermost surface when no load is applied or when a load is applied; and a load mechanism 18 that applies a load to the sound wave probe 2.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to an acoustic wave inspection device, an acoustic wave inspection method, and a holder for an acoustic wave inspection device.

Background Art

[0002] An acoustic wave inspection device that uses the propagation of acoustic waves such as ultrasonic waves and elastic waves is used for inspecting various members, devices, infrastructures, etc. Further, ultrasonic inspection devices are also used for medical diagnosis and the like. When installing an acoustic wave inspection probe such as an ultrasonic probe, an AE (Acoustic Emission) sensor, etc., which are acoustic wave receivers, acoustic wave transmitters, acoustic wave transceivers, etc., used in such inspection devices on a test object, in order to efficiently perform the propagation of acoustic waves between the acoustic wave inspection probe and the test object, a liquid or viscous contact medium such as glycerin, petrolatum, oil, etc. is interposed between the acoustic wave functional surface that constitutes at least one of the acoustic wave transmission surface and the reception surface of the probe and the test object. This is because if air, which has a significantly different acoustic impedance from the materials constituting the probe and the test object, intervenes between the materials, the sound will be reflected there and propagation will become extremely difficult.

[0003] The above-described contact medium is important for efficiently transmitting acoustic waves such as ultrasonic waves from the probe to the test object or from the test object to the probe and improving the test accuracy. However, the process of applying or removing a liquid or viscous contact medium is complicated. For this reason, it has become a factor that increases the inspection time and man-hours. In addition, depending on the test object to be inspected, it may be contaminated with the contact medium, and in that case, the inspection itself cannot be carried out.

[0004] Solid coupling media have also been proposed, but the propagation of ultrasound is significantly inferior compared to when liquid coupling media are used. To avoid the presence of air between the mounting surface of the coupling media for sound wave inspection and the object under inspection, adhesive solid coupling media have also been proposed. However, when conventional adhesive solid coupling media are used, the mounting surface of the coupling media for sound wave inspection adheres tightly to the object under inspection, making it impossible to slide the coupling media. Therefore, even when moving the mounting position by a small distance, it is necessary to detach the transducer along with the coupling media from the object under inspection, making the inspection process complicated. Furthermore, depending on how the solid coupling media is held to the transducer, there are issues such as the time and effort required to replace the coupling media. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2020-053956 [Patent Document 2] Japanese Patent Publication No. 2021-067603 [Patent Document 3] Japanese Patent Publication No. 2022-141589 [Overview of the project] [Problems that the invention aims to solve]

[0006] The problem that the present invention aims to solve is to provide an acoustic wave inspection device, an acoustic wave inspection method, and a holder for an acoustic wave inspection device that can effectively propagate sound waves when the coupling medium is in close contact with the object to be inspected during inspection, can easily move the coupling medium, and can easily replace the coupling medium. [Means for solving the problem]

[0007] The acoustic wave inspection apparatus of the embodiment comprises a transducer configured to perform at least one of transmitting and receiving sound waves, having an acoustic functional surface that constitutes at least one of a sound wave transmitting surface and a sound wave receiving surface; a contact member comprising a coupling medium containing an elastomer, having a first surface that contacts the acoustic functional surface of the acoustic wave probe directly or via an intermediate member, and a second surface opposite to the first surface; a sheet member having a plurality of openings containing a polymer, laminated with the coupling medium so as to contact the second surface; a holder for holding the contact member and attaching it to the acoustic wave probe, wherein a portion of the sheet member having a plurality of openings is fixed such that at least a portion of the sheet member having a plurality of openings is located on the outermost surface when unloaded or under load; and a load mechanism for applying a load to the acoustic wave probe. The holder has an opening for inserting the sonar probe and a portion for housing or holding the contact member, and is configured such that the sonar function surface of the sonar probe is in close contact with the coupling medium and the sonar probe is movable within the opening so that sound waves are transmitted and received between the sonar probe and the object under test from the opening. [Brief explanation of the drawing]

[0008] [Figure 1] This is a cross-sectional view showing a sound wave inspection device according to the first embodiment. [Figure 2] Figure 1 shows the inspection process of an object to be inspected using the acoustic inspection device shown in Figure 1. [Figure 3] Figure 1 shows the state of the contact medium and the sheet member with multiple openings in the acoustic inspection device shown in Figure 1 when unloaded. [Figure 4] Figure 1 shows the state of the contact medium and the sheet member with multiple openings under load in the acoustic wave inspection device shown. [Figure 5] This is a cross-sectional view showing a modified example of the sound wave inspection apparatus of the first embodiment. [Figure 6] This is a cross-sectional view showing a first example of a second embodiment of an acoustic inspection device. [Figure 7] This is a cross-sectional view showing a second example of the acoustic inspection device according to the second embodiment. [Figure 8] Figure 7 is a top view of the acoustic inspection device shown. [Figure 9] This is a cross-sectional view showing a modified example of the acoustic inspection apparatus according to the first or second embodiment. [Figure 10] Figure 9 is an exploded view of the acoustic inspection device shown. [Figure 11] It is a cross-sectional view showing a modified example of the acoustic wave inspection device according to the first or second embodiment. [Figure 12] It is a cross-sectional view showing a modified example of the acoustic wave inspection device according to the first or second embodiment. [Figure 13] It is a cross-sectional view showing a modified example of the acoustic wave inspection device according to the first or second embodiment. [Figure 14] It is an exploded view showing a modified example of the acoustic wave inspection device according to the first or second embodiment. [Figure 15] It is a plan view showing a first example (mesh sheet) of a sheet member having a plurality of openings. [Figure 16] It is a plan view showing a second example of a sheet member having a plurality of openings. [Figure 17] It is a plan view showing a third example of a sheet member having a plurality of openings. [Figure 18] It is a plan view showing a fourth example of a sheet member having a plurality of openings. [Figure 19] It is a plan view showing a fifth example of a sheet member having a plurality of openings. [Figure 20] It is a plan view showing a sixth example of a sheet member having a plurality of openings. [Figure 21] It is a plan view showing a seventh example of a sheet member having a plurality of openings.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, an acoustic wave inspection device, an acoustic wave inspection method, and a holder for an acoustic wave inspection device according to an embodiment will be described with reference to the drawings. In each embodiment, substantially the same constituent parts are denoted by the same reference numerals, and the description thereof may be partially omitted. The drawings are schematic, and the relationship between the thickness and the planar dimensions of each part, the ratio of the thicknesses of each part, etc. may be different from the actual ones. The terms indicating the vertical direction in the description indicate the relative direction when the inspection surface of the inspection object is taken as the upper side, and may be different from the actual direction based on the direction of the gravitational acceleration.

[0010] The sound waves described herein refer to all elastic vibration waves that propagate through an elastic medium, regardless of whether it is a gas, liquid, or solid. It includes not only sound waves in the audible frequency range but also ultrasonic waves having a frequency higher than the audible frequency range and low-frequency sounds having a frequency lower than the audible frequency range. The frequency of the sound waves is not particularly limited and includes those from high frequencies to low frequencies.

[0011] (First Embodiment) FIG. 1 shows a sound wave inspection device 1 according to the first embodiment, and FIG. 2 shows an inspection state in which the sound wave inspection device 1 is disposed on a test object X. The sound wave inspection device 1 shown in FIG. 1 includes an angled sound wave probe 2. The sound wave inspection device 1 has, for example, a pulse-echo type sound wave probe 2 and performs non-destructive inspection such as flaw detection or film thickness measurement by measuring sound waves (reflected waves) returning from inspection objects such as flaws in the test object. Alternatively, the sound wave probe 2 may perform non-destructive inspection such as flaw detection by measuring sound waves such as stress waves generated by the inspection object. The sound wave probe 2 has at least one function of transmitting and receiving sound waves, and specific examples include an ultrasonic transceiver (ultrasonic transducer) and a sound wave receiver. A representative example of the ultrasonic transceiver is an ultrasonic probe. A representative example of the sound wave receiver is an AE sensor. The sound wave probe 2 may be a sound wave transmitter.

[0012] In the acoustic wave inspection apparatus 1 of this embodiment, the acoustic wave probe 2 has a transmitting / receiving surface, a receiving surface, a transmitting surface, etc. Here, the surface constituting at least one of the transmitting surface and the receiving surface of the acoustic wave probe is referred to as the acoustic wave functional surface. Such an acoustic wave functional surface of the acoustic wave probe 2 is, for example, an ultrasonic probe as an ultrasonic transceiver. The ultrasonic probe 2 comprises an ultrasonic transmitting / receiving element 3 having a transducer (piezoelectric body) for ultrasonic flaw detection and electrodes provided on both the upper and lower surfaces of the transducer. The angled ultrasonic transmitting / receiving element 3 is arranged on a shoe 4 having a predetermined angle and is housed in a case 5 in this state. The ultrasonic transmitting / receiving element 3 is placed on a wave-receiving plate as needed. Sound-absorbing material 6 is provided on the back side of the shoe 4. Electrodes of the ultrasonic transmitting / receiving element 3 (not shown) are electrically connected to a connector 7 provided on the case 5. The transducer, ultrasonic transmitting / receiving element 3, shoe 4, wave-receiving plate, etc. can be made of known materials and structures used in ultrasonic probes, and are not particularly limited.

[0013] Furthermore, if the sound wave probe 2 is a sound wave receiver such as an AE sensor, the same configuration as that of the ultrasonic probe 2 is applied, except that a sound wave receiving element having an AE receiving transducer (piezoelectric material) is used. In that case, known constituent materials and structures used in AE sensors can be applied to the AE receiving transducer, sound wave receiving element, wave receiving plate, etc.

[0014] In the sound wave inspection apparatus 1 of the embodiment, if the sound wave probe 2 is an ultrasonic probe having at least one of the functions of transmitting and receiving sound waves, it may have an intermediate member called a shoe 4 or delay material made of a polymer material. As shown in Figure 1, in the angled ultrasonic probe 2, the transducer is mounted on the material that makes up the shoe 4. Acrylic, polystyrene, polyetherimide, etc. can be used as the shoe material. In the case of a vertical ultrasonic probe, it is mounted on an intermediate member called a delay material, as will be described later. The shoe or intermediate member called a delay material made of a polymer material is in contact with, for example, the sound wave functional surface of the ultrasonic probe 2. Furthermore, a contact member 10 is provided on the outer peripheral surface of the intermediate member, which functions as at least one of the sound wave transmitting surface and receiving surface, and which comprises a coupling medium 8 containing an elastomer that functions as a sound wave propagation part and a sheet member 9 containing a polymer that has a plurality of openings.

[0015] The contact member 10, which comprises a coupling medium 8 and a sheet member 9 having multiple openings, is held by a holder 11 and attached to the sonar probe 2 in this state. A portion of the contact member 10 is fixed to the holder 11. A portion of the sheet member 9 having multiple openings is bonded and fixed to the holder 11 by an adhesive sheet 12. The sonar inspection device 1 is positioned on the object to be inspected X so that the contact member 10 is in contact with the object to be inspected X. The sonar inspection device 1 has, for example, a pulse reflection method and performs non-destructive inspection of defects, etc., inside the object to be inspected X by measuring sound waves from the object to be inspected X. The contact member 10 comprises a coupling medium 8 containing an elastomer and a sheet member 9 having multiple openings containing a polymer provided on the contact surface for the coupling medium 8 to contact the object to be inspected.

[0016] The sound wave inspection device 1 is used by attaching a holder 11 that holds a contact member 10 to a sound wave probe 2. In the sound wave inspection device 1 shown in Figure 1, the holder 11 has a side wall portion (base member) 13 provided so as to surround the contact member 10, a cover portion 15 provided so as to cover the upper part of the side wall portion 13 and having an opening 14, and a pressing portion 16 that extends upward around the opening 14 in the same shape as the opening 14. The opening 14 is provided from inside the side wall portion 13 to inside the pressing portion 16. An adhesive sheet 12 is placed at the lower part of the side wall portion 13, and a part of a sheet member 9 having multiple openings is adhesively fixed to the holder 11 by the adhesive sheet 12. The sound wave probe 2 is movably inserted into the opening 14 formed in the holder 11.

[0017] The sonar probe 2 may be used simply by being inserted into the retaining portion 16 and the opening 12, or, as shown in Figure 5, it may be used by fixing the holder 11 to the sonar probe 2 using a mechanism such as a plunger 17 and integrating them. The holder 11 shown in Figure 5 has a side wall portion 13 that surrounds the contact member 10, and a plunger 17 is provided on the side wall portion 13. The plunger 17 is positioned and fixed in a through hole provided in the side wall portion 13 (or retaining portion 16) of the holder 11, and by pressing the ball or pin at the tip against the sonar probe 2 with an internal spring or the like, it fixes the sonar probe 2 in a state that allows for vertical movement and attachment / detachment.

[0018] The holder 11 shown in Figure 1 has an opening 14 into which a sonar probe is inserted. Furthermore, the holder 11 has a space at the bottom for storing a coupling medium 8 containing an elastomer, and a sheet member 9 having multiple openings is installed at the bottom via an adhesive sheet 12. The sonar inspection device 1 shown in Figure 5 is an example in which a contact member 10 and a holder 11 applicable to angled sonar probes 2 of various sizes are applied. The holder 11 is equipped with a mechanism for holding the sonar probe 2 around its periphery, and has a configuration that allows the holder 11 holding the contact member 10 to be attached to sonar probes 2 of different sizes and shapes.

[0019] A coupling medium 8 containing an elastomer is in close contact with the sonic function surface of the sonic probe 2. As shown in Figure 3, in the initial state (unloaded state), a sheet member 9 having multiple openings and containing a polymer, fixed to the holder 11, is located on the surface that contacts the test specimen X. The sheet member 9 with multiple openings is located on the outermost surface of the sonic inspection device 1. Here, the outermost surface refers to the contact surface with the object to be inspected X, and is the outermost surface of the sonic inspection device 1 on the side opposite to the sonic probe 2. Since a portion of the sheet member 9 with multiple openings is fixed to the holder 11, the sonic probe 2, which is integrated with the contact member 10 and the holder 11, can be easily slid over the object to be inspected X.

[0020] When performing an acoustic inspection, a load P is applied to the acoustic probe 2 by the load application device 18. This load P is then applied to the coupling medium 8, which contains an elastomer and is in contact with the acoustic surface of the acoustic probe 2. As shown in Figure 4, the coupling medium 8 containing the elastomer is pressed against a sheet member 9 having multiple openings and containing a polymer, which is partially fixed to the holder 11. Since part of the sheet member 9 with multiple openings is fixed to the holder 11, the coupling medium 8 containing the elastomer fills the mesh of the sheet member 9 and protrudes toward the object under inspection X, expelling the air that was between it and the contact member 10, and causing the coupling medium 8 to come into direct contact with the object under inspection X. This allows sound waves such as ultrasound to be propagated from the acoustic probe 2 to the object under inspection X.

[0021] The load application device 18 can be an actuator such as a mechanical, hydraulic, pneumatic, or electromagnetic actuator. The load application device 18 is installed on the sonar probe 2 and is configured to apply a load directly to the sonar probe 2, thereby applying the load to the contact member 10 via the sonar probe 2. The load application mechanism 18 for the sonar probe 2 and the contact member 10 only needs to be able to switch between a state in which a load is applied to the contact member 10 and a state in which the load is removed, and the specific load application method and the shape of the application member are not particularly limited. When the load applied by the load application device 18 is removed, the deformation of the coupling medium 8 containing the elastomer due to the load is eased, and the sheet member 9 having mainly multiple openings comes into contact with the object under inspection X. Therefore, the sonar probe 2, which is integrated with the contact member 10 and the holder 11, can easily slide over the object under inspection X again.

[0022] As described above, by fixing a portion of the contact member 10, which comprises a coupling medium 8 containing an elastomer and a sheet member 9 having multiple openings containing a polymer, to the holder 11, sound waves can be efficiently propagated between the contact member 10 and the object under inspection X when a load is applied, and when the load is removed, the sound wave probe 2, which is integrated with the contact member 10 and the holder 11, can be moved on the object under inspection X. This makes it possible to achieve both non-destructive testing by the sound wave inspection device 1 and the mobility of the sound wave inspection device 1. Here, the holder 11 may be a resin member or a metal member made by a 3D printer or the like, or it may be made from various materials such as wood, resin, metal, glass, or composite materials thereof.

[0023] When the frictional force of the elastomer constituting the coupling medium 8 is measured, it is overwhelmingly large compared to other materials. The origin of this large frictional force is presumed to be a phenomenon observed because the elastomer deforms, resulting in an extremely large contact area. Even when hard materials such as metals are brought into contact, only a very small part of the contact surface, specifically the roughness, or the tips of the microscopic protrusions on the surface, makes contact. However, in the case of materials with a low elastic modulus, such as elastomers, the contact area is larger even with the same load, and the adsorption force increases in proportion to the contact area. In addition, the viscoelasticity of the elastomer acts in a direction that increases the force that peels away the adsorption interface in contact, which also contributes to the large coefficient of friction. Thus, because the elastomer has a large effective (microscopic) contact area with the object under inspection X, it can transmit ultrasound well. However, the more easily ultrasound is transmitted, the greater the frictional force and the more difficult it becomes to peel it away.

[0024] Therefore, in the contact member 10 and holder 11 shown in Figure 1, a sheet member 9 having multiple openings containing a polymer is provided on the surface of the coupling medium 8 containing an elastomer. The sheet member 9 having multiple openings is made of a material with a higher modulus of elasticity than the coupling medium 8 containing an elastomer. A portion of the sheet member 9 having multiple openings is fixed to the holder 11. By using a holder 11 that holds a contact member 10 equipped with such a coupling medium 8 and a sheet member 9 having multiple openings, when no load is applied, the protrusions of the uneven surface of the sheet member 9 having multiple openings, which has a higher modulus of elasticity, come into contact with the object to be inspected X, and the coupling medium 8 containing an elastomer does not come into contact with the object to be inspected X, so it can be moved with a small frictional force. When a load is applied, the coupling medium 8 containing an elastomer deforms and protrudes between the protrusions of the sheet member 9 having multiple openings, so that the coupling medium 8 comes into contact with the object to be inspected X, and sound waves can be propagated efficiently.

[0025] In a sheet member 9 having multiple openings containing a polymer, if the sheet member 9 is a mesh sheet, the diameter of the protrusions, i.e., the threads constituting the mesh, is preferably 10 μm or more and 500 μm or less. If the sheet member 9 has multiple openings formed in the sheet, the distance between the openings is preferably 10 μm or more and 500 μm or less. This finding was obtained by measuring the sound propagation performance when a load is applied and the coefficient of friction with the object under inspection X when no load is applied. If a sheet member 9 with multiple openings that deviate from this range is used, the sound wave propagation performance tends to be low and the sliding on the object under inspection X tends to be poor. The width between the protrusions, i.e., the mesh opening of a mesh sheet or the major axis of the openings in a sheet with multiple openings, is preferably 10 μm or more and 2000 μm or less. If the minimum width between the protrusions, i.e., the mesh opening of the sheet or the major axis of the openings in a sheet with multiple openings, exceeds 2000 μm in either case, there is a risk that the frictional force reduction effect by bringing only the protrusions into contact with the object under inspection X may not be sufficiently obtained when no load is applied. If the width between the protrusions, i.e., the minimum width of the mesh opening or the major axis of the sheet opening, is less than 10 μm, there is a risk that the coupling medium 8 may not be able to come into sufficient contact with the object under inspection X when a load is applied.

[0026] Furthermore, in a contact member 10 composed of a coupling medium 8 containing an elastomer and a sheet member 9 having a plurality of openings containing a polymer, when the portion of the uneven surface that contacts the object under inspection X is defined as a convex portion, it is preferable that the total area of ​​the concave portion (area projected onto a plane) is larger than the total area of ​​the convex portion (area projected onto a plane) when the surface having an uneven structure is viewed from the normal direction. This makes it possible to improve the efficiency of sound wave propagation between the coupling medium 8 and the object under inspection X. The minimum width of the convex portion, the minimum width of the concave portion, the ratio of the total area of ​​the convex portion to the total area of ​​the concave portion, etc., are preferably selected appropriately according to the Young's modulus and acoustic impedance of the material used for the coupling medium 8.

[0027] The thickness of the coupling medium 8 containing the elastomer is preferably 10 μm or more and 10 mm or less. The appropriate thickness varies depending on the acoustic impedance and Young's modulus of the materials constituting the coupling medium 8, but when the thickness is particularly high, such as 0.2 mm or more and 2 mm or less, the sound wave propagation performance is high and the lubricity on the object X under inspection can also be improved. The elastomer included in the constituent materials of the coupling medium 8 includes thermosetting elastomers and thermoplastic elastomers, but both can be used in the coupling medium 8 of the embodiment. A thermoplastic elastomer is, for example, a copolymer of two or more polymers with different temperature dependence of elastic modulus. The elastomer used in the embodiment has a predetermined viscoelasticity and can adhere to the object, so it does not contaminate the surroundings compared to other coupling media such as water and oil, and because it is solid, it is easy to remove and can be reused. In order to eliminate the air layer by pressing the coupling medium, the elastic constant (Young's modulus) of the elastomer used is preferably 0.1 MPa or more and 0.1 GPa or less. The yield stress, which is the stress at which plasticity of the material begins, is preferably high, preferably 2 MPa or higher, and more preferably 20 MPa or higher. The tensile strength is also preferably high, preferably 2 MPa or higher.

[0028] Examples of thermoplastic elastomers that primarily constitute the coupling medium 8 include polystyrene-based thermoplastic elastomers (SBC, TPS), polyolefin-based thermoplastic elastomers (TPO), vinyl chloride-based thermoplastic elastomers (TPVC), polyurethane-based thermoplastic elastomers (TPU), polyester-based thermoplastic elastomers (TPEE, TPC), and polyamide-based thermoplastic elastomers. Examples of thermosetting elastomers include styrene-butadiene rubber (SBR), isoprene rubber (IR), butadiene rubber (BR), chloroprene rubber (CR), and acrylonitrile-butadiene rubber (NBR), which are classified as diene rubbers; butyl rubber such as isobutylene-isoprene rubber (IIR), ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), urethane rubber (U), silicone rubber, and fluororubber (FKM), which are classified as non-diene rubbers; and other rubbers such as chlorosulfonated polyethylene (CSM), chlorinated polyethylene (CM), acrylic rubber (ACM), polysulfide rubber (T), and epichlorohydrin rubber (CO, ECO). Each material has its own characteristics in terms of heat resistance, abrasion resistance, oil resistance, chemical resistance, etc., so it is preferable to select the appropriate material depending on the object to be inspected. Depending on the application, multiple elastomers may be mixed and used. Additives with a size that does not obstruct the transmission of sound waves, i.e., generally 200 μm or less in diameter, may be mixed in.

[0029] The polymer-containing member 9, which has multiple openings, can slide over the object to be inspected X when no load is applied, due to the convex portions of the uneven structure of the sheet member 9 with multiple openings. This is because the material constituting the sheet member 9 with multiple openings is made of a material harder than the coupling medium 8, and the convex portions have a shape that minimizes the contact area with the object to be inspected X. The sheet member 9 with multiple openings that constitute the convex portions is often made mainly of polymer material. For example, polymers with a higher elastic modulus than elastomers that mainly constitute the coupling medium 8 are used, such as polyester, polyethylene, polypropylene, nylon, tetrafluoroethylene, tetrafluoroethylene hexafluoropropylene copolymer, tetrafluoroethylene ethylene copolymer, vinylidene fluoride, and other fluororesins, ABS resin, polystyrene, methacrylic resin, polycarbonate, polyacetal, polyurethane, polyvinylidene chloride, polyethylene terephthalate, liquid crystal, and polyvinyl chloride. Alternatively, various polymer meshes may be sputtered with metal or the like. Other materials such as metals, ceramics, and oxides may also be used.

[0030] When the sheet member 9 having multiple openings containing polymer that constitutes the contact member 10 is a mesh sheet, it is not limited to a plain weave made by alternately crossing warp and weft threads. It may also be a twill weave or satin weave made by crossing warp and weft threads with two threads skipped each. Furthermore, the warp and weft threads may not be woven perpendicularly to each other; for example, the warp threads may be tilted at about 20 degrees. Moreover, it is desirable to fuse the intersections of the mesh because this often increases the strength of the sheet member 9 having multiple openings. In addition, when the contact member 10 is constructed in combination with the coupling medium 8, the sound wave propagation performance may be improved.

[0031] (Second embodiment) Figure 6 shows a second embodiment of the sound wave inspection device 1. The sound wave inspection device 1 shown in Figure 6 is equipped with a vertical type sound wave probe 2. The sound wave inspection device 1 has, for example, a pulse reflection type sound wave probe 2 and performs non-destructive testing such as flaw detection or film thickness measurement by measuring sound waves (reflected waves) returning from the object to be inspected, such as a defect inside the object to be inspected. Alternatively, the sound wave probe 2 may perform non-destructive testing such as flaw detection by measuring sound waves such as stress waves generated by the object to be inspected. The sound wave probe 2 has at least one of the functions of transmitting and receiving sound waves, and specific examples include ultrasonic transceivers (ultrasonic transducers) and sound wave receivers. A typical example of an ultrasonic transceiver is an ultrasonic probe. A typical example of a sound wave receiver is an AE sensor. The sound wave probe 2 may also be a sound wave transmitter. In the vertical type acoustic probe 2, the ultrasonic transmitting / receiving element (or acoustic wave receiving element) 3 may be placed on a delay material 31, as shown in Figure 7, and a damper 20 may be placed on top of it. The intermediate members such as the delay material 19 are as described above.

[0032] The holder 11 shown in Figure 6 has a stepped opening 23 having a first opening 21 for inserting the sonar probe 2 and a second opening 22 for inserting the coupling medium 8 of the contact member 10. The first opening 21 and the second opening 22 are arranged to communicate with each other. Below the holder 11, the second opening 22 is provided as a space for storing the coupling medium 8 containing elastomer, and above it, the first opening 21 is provided as a space for storing the sonar probe 2. A sheet member 9 having multiple openings is adhesively fixed to the bottom of the side wall portion 13 of the holder 11 where the first opening 21 and the second opening 22 are provided, via an adhesive sheet 12.

[0033] In Figure 6, the sonar probe 2 is used simply by being inserted into the first opening 21. The sonar probe 2 may also be used by fixing the holder 11 to the sonar probe 2 using a mechanism such as a plunger 17, as shown in Figures 7 and 8. Figures 7 and 8 show examples of applying the contact member 10 and holder 11, which can be applied to vertical sonar probes 2 of various shapes, such as cylindrical and rectangular parallelepipeds, and of various sizes. The periphery of the holder 11 is equipped with a mechanism for holding the sonar probe 2, making it possible to attach the holder 11 holding the contact member 10 to sonar probes 2 of different sizes and shapes. Here, a plunger 17 is used as the mechanism for holding the sonar probe 2. For example, when applying a cylindrical sonar probe 2 as shown in Figure 8, the plunger 17 is positioned to press against three points divided into three sections on the outer surface of the sonar probe 2. The plunger 17 has a compression spring 17a inside and a tip member 17b, such as a ball or pin, positioned at the tip of the compression spring 17a. The compression spring 17a presses the tip member 17b against the sonar probe 2 to secure it. Since the position of the tip member 17b of the plunger 17 is variable due to the expansion and contraction of the compression spring 17a, the sonar probe 2 can be detachably fixed.

[0034] The holder 11 shown in Figures 7 and 8 comprises a base member 24 and a retaining member 25 provided on its upper part. The base member 23 has a first opening 26 that forms a space for housing the contact member 10. The retaining member 25 has a second opening 27 that forms a space for housing the sonar probe 2. A projection 28 is provided at the inner lower end of the first opening 26 of the base member 23, on which an adhesive sheet 12 is placed. The sheet member 9 having multiple openings is adhesively fixed by the adhesive sheet 12 placed on the projection 28. Since the sheet member 9 having multiple openings is fixed to the projection 28 provided at the inner lower end of the first opening 26, it is bent according to the thickness of the projection 28 so that a part of the sheet member 9 having multiple openings is located on the outermost surface while maintaining its fixed state to the projection 28. The coupling medium 8 is placed on the sheet member 9 having multiple openings in a deformed state so as to contact such sheet member 9 having multiple openings. Furthermore, the deformed shape of the coupling medium 8 and the folded shape of the sheet member 9 having multiple openings may be such shapes from the beginning, or they may take on such shapes when a load is applied. In other words, the sheet member 9 having multiple openings may be located on the outermost surface when unloaded, or it may be deformed to be located on the outermost surface when a load is applied.

[0035] As shown in Figures 9 and 10, the base member 24 may have a shape such that a space is created between it and the sheet member 9 having multiple openings on its outer circumference for placing the adhesive sheet 12. In Figures 9 and 10, the sheet member 9 having multiple openings is placed below the base member 24, and a portion of the sheet member 9 having multiple openings is bonded and fixed to the lower side of the base member 24 by the adhesive sheet 12 placed between the outer circumference of the base member 24 and the sheet member 9 having multiple openings. Figure 9 is a cross-sectional view of the sound wave inspection device 1, and Figure 10 is an exploded view of the sound wave inspection device 1.

[0036] In the sound wave inspection apparatus 1 shown in Figures 9 and 10, the base member 23 has a first opening 26 that forms a space for housing the contact member 10, and the retaining member 25 has a second opening 27 that forms a space for inserting the sound wave probe 2. The space for housing the contact member 10 is provided by the first opening 26, which is larger than the bottom area of ​​the sound wave probe 2. The coupling medium 8 is stored in the first opening 26. The sheet member 9 having multiple openings is bonded to the bottom of the base member 24 with an adhesive sheet 12, as described above. The coupling medium 8 stored in the first opening 26 is pressed against the sheet member 9 having multiple openings and deformed, thereby enabling it to propagate sound waves between itself and the object to be inspected X. In this case, the sound wave probe 2 is only housed in the first opening 26 formed in the retaining member 25 and is not fixed to the holder 11.

[0037] As shown in Figure 11, the sound wave probe 2 in the sound wave inspection device 1 may be detachably fixed by a plunger 17 provided on the retaining member 25. By fixing the sound wave probe 2 with the plunger 17 provided on the retaining member 25, the contact member 10 and the holder 11 are integrated with the sound wave probe 2, thereby improving the mobility of the sound wave inspection device 1 equipped with the sound wave probe 2 on the object to be inspected X.

[0038] As shown in Figure 12, the holder 11 of the sound wave inspection device 1, similar to Figure 7, has a projection 28 provided at the inner lower end of the first opening 26 of the base member 23, and a sheet member having multiple openings may be bonded and fixed by an adhesive sheet 12 placed on the projection 28. In this case, similar to Figure 7, the sheet member 9 having multiple openings may have a folded shape according to the thickness of the projection 28 so that a part of it is located on the outermost surface. The folded shape of the sheet member 9 having multiple openings may be such from the beginning, or it may take on such a shape when a load is applied. That is, the sheet member 9 having multiple openings may be located on the outermost surface when unloaded, or it may be deformed to be located on the outermost surface when loaded.

[0039] In the acoustic wave inspection apparatus 1 shown in Figure 12, the contact member 10, which comprises a coupling medium 8 and a sheet member 9 having multiple openings, is housed between the base member 24 and the pressing member 25. In this case, it is preferable to deform the sheet member 9 having multiple openings to match the irregularities of the base member 24. If the sheet member 9 having multiple openings is mainly made of thermoplastic resin, heating it causes, for example, the peripheral portion to deform upward by a dimension equal to the thickness of the innermost part of the base member 24 plus the thickness of the adhesive sheet 12. The sheet member 9 having multiple openings, thus deformed, is then bonded to the base member 24 via the adhesive sheet 12.

[0040] Furthermore, the coupling medium 9 and the sheet member 9 having multiple openings in the contact member 10 of the sound wave inspection device 1 may be mechanically fixed by a holder 11 comprising a base member 24 and a pressing member 25, as shown in Figure 13. In the sound wave inspection device 1 shown in Figure 13, the coupling medium 9 and the sheet member 9 having multiple openings are sandwiched between the base member 24 and the pressing member 25, and the coupling medium 9 and the sheet member 9 having multiple openings are mechanically fixed using a mechanical fastener such as a bolt 29 attached from the side of the pressing member 25.

[0041] As shown in Figure 14, the sonar probe 2 and the contact member 10 are housed in a holder 11 consisting of a box-shaped retaining member 30. The sheet member 9 having multiple openings, which is placed inside the box-shaped retaining member 30, is fixed to the box-shaped retaining member 30 using an adhesive sheet 12 or adhesive. In this case, it is preferable to deform the sheet member 9 having multiple openings so that its peripheral portion conforms to the box-shaped retaining member 30 before housing it, as in Figure 12. This is preferable so that when the holder 11 is viewed from the side, the box-shaped retaining member 3 and the sheet member 9 having multiple openings are on the same plane, or the sheet member 9 having multiple openings is convex downwards from the box-shaped retaining member 3.

[0042] The sonar 2, contact member 10, holder 11, etc. in the first embodiment and the sonar 2, contact member 10, holder 11, etc. in the second embodiment can be applied in various combinations. For example, various combinations can be applied, such as applying a vertical sonar 2 to the sonar inspection device 1 shown in Figure 1. Also, if the surface of the object to be inspected is not flat, the holder 11 may have a curved surface with an arc-shaped cross-section to conform to the object to be inspected. In such cases, it is preferable to process the shape and thickness of the coupling medium 8 containing elastomer, or the shoe, protective layer, or delay material of the sonar 2 to conform to the object to be inspected.

[0043] Figures 15 to 21 show examples of sheet members 9 having multiple openings. Figure 15 is an example of a mesh sheet member, and Figures 16 to 21 are examples of sheet members with multiple openings formed in the sheet. In the mesh sheet member shown in Figure 15, 32 indicates the mesh portion (warp or weft threads), and 33 indicates the opening (mesh opening). In the sheet member 34 with multiple openings formed in the sheet, the shape of the openings 35 may be any of the following shapes: round holes as shown in Figures 16 and 17, square holes (polygonal holes) as shown in Figure 18, hexagonal holes (polygonal holes) as shown in Figure 19, oval holes as shown in Figure 20, rectangular holes as shown in Figure 21, etc. In Figures 16 to 21, reference numeral 36 indicates a sheet portion, and reference numeral 37 indicates the shortest distance between the openings 35. [Examples]

[0044] The following describes examples and their evaluation results.

[0045] (Example 1, Comparative Example 1) As shown in Tables 1 and 2, various combinations of contact members and holders were prepared, and their performance was evaluated using a vertical or angled beam probe with a frequency of 2.0 MHz. The shoe material of the probe shown in Tables 1 and 2 refers to the shoe material in the case of an angled beam probe, and the delay material material in the case of a vertical beam probe. The items in Tables 1 and 2 are explained below. A holder is a device that integrates an elastomer sheet and a mesh sheet member and attaches them to the probe. The presence or absence of a holder indicates whether or not a holder was used in the test. The holder structure used was as shown in Figures 1 to 10. "Presence or absence of fixing of the mesh sheet member" indicates whether or not the mesh sheet member is fixed to the holder by adhesive, adhesive sheet, or physical process such as a jig. Mesh sheet members with different materials, mesh thread diameters, and mesh openings (distance between threads) were used to confirm the effects of the embodiment. For the elastomer, polystyrene thermoplastic elastomers (SBC, TPS) with different hardness and thickness were used.

[0046] First, the movement characteristics of the ultrasonic inspection device were evaluated. Initially, a shear tensile test was performed to determine whether the ultrasonic inspection device (ultrasonic probe) could be moved using only its own weight without any additional load. A load cell was connected to the ultrasonic probe, and it was placed on a stainless steel plate with a surface roughness Rz of 18 μm. The device was then moved at a low speed across the stainless steel plate, and the static friction coefficient was measured. As a comparative example, measurements were also taken when no holder was used and when the mesh sheet member was not fixed to the holder. As a result, when no holder was used or the mesh sheet member was not fixed to the holder, the static friction coefficient was larger compared to when the mesh was fixed to the holder. When a holder that housed or fixed various contact members was used, the static friction coefficient uniformly decreased, indicating that movement was possible. In the case of the holders shown in Figures 12, 13, and 14, the shape of the mesh sheet member was processed to match the shape of the holder so that the mesh sheet member contacts the surface of the object being inspected. In these cases, the coefficient of static friction was higher compared to when the mesh sheet member was installed along the surface of the object being inspected, as shown in Figures 1 and 9. The results are shown in Tables 1 and 2.

[0047] Next, ultrasonic testing was performed. A 300 mm long carbon steel block was prepared. The surface roughness Rz of the surface on which the ultrasonic waves were incident was set to 18 μm, and the surface roughness Rz of the surface on which the ultrasonic waves were reflected was set to 1.6 μm. An ultrasonic probe with a load of 18 kPa was applied to the ultrasonic probe using an electromagnetic actuator and the testing was performed under conditions where the probe was pressed against the carbon steel block. The results, along with the friction coefficient results, are shown in Table 1. It was observed that the larger the mesh opening ratio of the mesh sheet, the larger the amplitude of the reflected wave waveform and the better the result tended to be. When an elastomer with a high Asker C hardness was used, the amplitude of the reflected wave waveform decreased, making ultrasonic testing more difficult.

[0048] [Table 1]

[0049] [Table 2]

[0050] (Example 2, Comparative Example 2) As shown in Table 3, various combinations of contact members and holders were prepared, and their performance was evaluated using a vertical or angled beam probe with a frequency of 3.5 MHz. The shoe material of the probe shown in Table 3 refers to the shoe material in the case of an angled beam probe, and the delay material material in the case of a vertical beam probe. The items in Table 3 are explained below. A holder is a device that integrates an elastomer sheet and a sheet with multiple openings and attaches it to the probe. The presence or absence of a holder indicates whether or not a holder was used in the test. The holder structures used were those shown in Figures 1 to 10. "Presence or absence of fixing of the sheet member" indicates whether or not the sheet with multiple openings containing polymer is fixed to the holder by adhesive, adhesive sheet, or physical process such as a jig. Sheet members with different materials, opening shapes, protrusion widths or distances between openings, distances between protrusions or opening diameters were used to confirm the effects of the embodiments. The material, hardness, and thickness of the elastomers used are also shown in Table 3.

[0051] First, the movement characteristics of the ultrasonic inspection device were evaluated. Initially, a shear tensile test was performed to determine if the ultrasonic inspection device (ultrasonic probe) could be moved under its own weight without any additional load. A load cell was connected to the ultrasonic probe, placed on an aluminum plate with a surface roughness Rz of 35 μm, and moved at a low speed across the aluminum plate to measure the static friction coefficient. For comparative examples, measurements were also taken without a holder and without fixing the sheet member to the holder. The results showed that the static friction coefficient was higher without a holder or without fixing the sheet member compared to when the sheet member was fixed to the holder. When a holder containing or fixing various contact members was used, the static friction coefficient uniformly decreased, indicating that movement was possible. The results are shown in Table 3 along with the measurement conditions.

[0052] Next, ultrasonic testing was performed. A carbon steel block with a length of 300 mm was prepared. The surface roughness Rz of the surface on which the ultrasonic waves were incident was set to 18 μm, and the surface roughness Rz of the surface on which the ultrasonic waves were reflected was set to 1.6 μm. An ultrasonic probe with a load of 18 kPa was applied using an electromagnetic actuator and the testing was performed under conditions where it was pressed against the carbon steel block. The results, along with the friction coefficient results, are shown in Table 3. It was observed that the larger the distance between the protrusions of the sheet member or the larger the aperture diameter, the larger the amplitude of the reflected wave waveform and the better the result tended to be.

[0053] [Table 3]

[0054] Although several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0055] 1...Sound wave inspection device, 2...Sound wave probe, 3...Ultrasonic transmitting / receiving element (sound wave receiving element), 4...Shoe, 5...Probe case, 6...Sound absorbing material, 7...Connector, 8...Coupling medium, 9...Sheet member with multiple openings, 10...Contact member, 11...Holder, 12...Adhesive sheet or adhesive, 13...Holder, 14...Opening, 15...Holder, 16...Holder, 17...Plunger, 18...Load application device, 19...Holder, 20...Damper 21...Opening, 22...Opening, 23...Opening, 24...Holder (base member), 25...Holder (pressing member), 26...First opening, 27...Second opening, 28...Holder, 29...Fixing device, 30...Box-shaped pressing member, 31...Delaying material, 32...Mesh part of mesh sheet, 33...Opening (mesh opening), 34...Sheet with multiple openings, 35...Opening, 36...Sheet portion, 37...Width of protrusion or distance between openings.

Claims

1. A sound wave probe comprising a vibrator configured to perform at least one of transmitting and receiving sound waves, and having a sound wave functional surface that constitutes at least one of the sound wave transmitting surface and the sound wave receiving surface, A contact member comprising a coupling medium containing an elastomer, having a first surface that contacts the acoustic functional surface of the acoustic probe directly or via an intermediate member, and a second surface opposite to the first surface, and a sheet member laminated with the coupling medium so as to contact the second surface, and having a plurality of openings containing a polymer, A holder for holding the contact member and attaching it to the sound wave probe, wherein a portion of the sheet member having a plurality of openings is fixed such that at least a portion of the sheet member having a plurality of openings is located on the outermost surface when unloaded or under load, A load mechanism for applying a load to the aforementioned sound wave probe and It is equipped with, The holder has an opening for inserting the sonar probe and a portion for housing or holding the contact member, and is configured such that the sonar functional surface of the sonar probe is in close contact with the coupling medium and the sonar probe is movable within the opening so that sound waves are transmitted and received between the sonar probe and the object under test from the opening.

2. A sonar probe comprising a vibrator configured to perform at least one of transmitting and receiving sound waves, and having a sound wave functional surface that constitutes at least one of a sound wave transmitting surface and a sound wave receiving surface, A contact member comprising a coupling medium containing an elastomer, having a first surface that contacts the acoustic functional surface of the acoustic probe directly or via an intermediate member, and a second surface opposite to the first surface, and a sheet member laminated with the coupling medium so as to contact the second surface, and having a plurality of openings containing a polymer, A holder for holding the contact member and attaching it to the sound wave probe, wherein a portion of the sheet member having a plurality of openings is fixed such that at least a portion of the sheet member having a plurality of openings is located on the outermost surface when unloaded or under load, A load mechanism for applying a load to the aforementioned sound wave probe and It is equipped with, The acoustic inspection device comprises a retaining member having a first opening into which the acoustic probe is inserted so as to be movable, and a base member provided to communicate with the first opening and having a second opening into which the coupling medium is stored.

3. The acoustic wave inspection apparatus according to claim 2, wherein the sheet member having the plurality of openings is adhesively fixed to the lower end surface of the base member.

4. The sound wave inspection apparatus according to claim 2, wherein the sheet member having the plurality of openings is adhesively fixed to a projection provided inward at the lower end of the second opening.

5. The acoustic wave inspection apparatus according to claim 2, wherein the sheet member having the plurality of openings is fixed by adhesive sheet placed in the space on the outer periphery between the base member and the sheet member having the plurality of openings.

6. The acoustic wave inspection apparatus according to claim 2, wherein the coupling medium and the sheet member having the plurality of openings are sandwiched and fixed between the base member and the pressing member.

7. The sound wave inspection apparatus according to claim 2, wherein the retaining device is provided on the pressing member and comprises a plurality of plungers whose tips are pressed against the outer surface of the sound wave probe to be detachably fixed.

8. A sonar probe comprising a vibrator configured to perform at least one of transmitting and receiving sound waves, and having a sound wave functional surface that constitutes at least one of a sound wave transmitting surface and a sound wave receiving surface, A contact member comprising a coupling medium containing an elastomer, having a first surface that contacts the acoustic functional surface of the acoustic probe directly or via an intermediate member, and a second surface opposite to the first surface, and a sheet member laminated with the coupling medium so as to contact the second surface, and having a plurality of openings containing a polymer, A holder for holding the contact member and attaching it to the sound wave probe, wherein a portion of the sheet member having a plurality of openings is fixed such that at least a portion of the sheet member having a plurality of openings is located on the outermost surface when unloaded or under load, A load mechanism for applying a load to the aforementioned sound wave probe and It is equipped with, The holder comprises a side wall portion having an opening into which the sonar probe is inserted so as to be movable and into which the coupling medium is stored, and a plurality of plungers provided on the side wall portion, the tips of which are pressed against the outer surface of the sonar probe to fix it detachably. The sheet member having the plurality of openings is adherently fixed to the lower end surface of the side wall portion in an acoustic inspection device.

9. A sound wave inspection method using a sound wave inspection apparatus according to any one of claims 1 to 8, The steps include: placing the sound wave inspection device on the object to be inspected; A step of applying a load to the sound wave probe and pressing the coupling medium against the object to be inspected via the sheet member having the plurality of openings, The process involves pressing the coupling medium against the object to be inspected and performing a non-destructive inspection of the object to be inspected using the sound wave probe, The process involves removing the load on the contact member, moving the sound wave inspection device over the object to be inspected while the sheet member having the plurality of openings is in contact with the object to be inspected, and A sound wave inspection method comprising the following:

10. A holder for attaching a contact member to an acoustic probe, comprising a coupling catalyst containing an elastomer and a sheet member having a plurality of openings containing a polymer, A holder for an acoustic inspection device, comprising: an opening for inserting the acoustic probe; a portion for housing or holding the contact member such that at least a part of the sheet member having the plurality of openings is located on the outermost surface when unloaded or under load; a retaining member having a first opening into which the acoustic probe is movably inserted; and a base member provided to communicate with the first opening and having a second opening into which the coupling medium is stored, wherein a part of the sheet member having the plurality of openings is fixed.

11. The holder for an acoustic inspection device according to claim 10, wherein the sheet member having the plurality of openings is adhesively fixed to the lower end surface of the base member.

12. The holder for an acoustic inspection device according to claim 10, wherein the sheet member having the plurality of openings is adhesively fixed to a projection provided inward at the lower end of the second opening.

13. The holder for an acoustic inspection device according to claim 10, comprising a plurality of plungers provided on the pressing member, the tip of which is pressed against the outer surface of the acoustic probe to fix it detachably.

14. The sound wave probe is inserted so as to be movable and the side wall portion has an opening into which the coupling medium is stored, and the device comprises a plurality of plungers provided on the side wall portion, the tip of which is pressed against the outer surface of the sound wave probe to fix it detachably, The holder for an acoustic inspection device according to claim 10, wherein the sheet member having the plurality of openings is adhesively fixed to the lower end surface of the side wall portion.

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