Ultrasonic probe

Abstract

The utility model provides an ultrasonic probe which comprises a probe body, a first end face of the probe body is provided with a containing groove, and an electric connecting piece penetrates through the containing groove. The ultrasonic sensing unit comprises a piezoelectric ceramic piece, the piezoelectric ceramic piece is electrically connected with the electric connecting piece, and the ultrasonic sensing unit is provided with a retraction position at least partially contained in the containing groove and a protruding position at least partially protruding out of a notch of the containing groove; the elastic piece is positioned in the accommodating groove and is clamped between the ultrasonic sensing unit and the groove bottom wall of the accommodating groove, so that the ultrasonic sensing unit can be switched from a retraction position to a protruding position; and the fixing part is used for fixing the probe main body on the bolt to be monitored. According to the utility model, the pre-tightening force of the to-be-monitored bolt with the notch and the pre-tightening force of the to-be-monitored bolt without the notch are monitored in an integrated structure, so that the installation workload of monitoring operators is effectively reduced, and the operation intensity is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of bolt pre-tightening force acoustic time monitoring device design, in particular to an ultrasonic probe. Background Art

[0002] Among the popular ultrasonic monitoring technologies today, the ultrasonic method has the advantages of high precision, easy installation and low cost, and is widely used in the field of non-destructive monitoring. It is widely used in the field of bolt condition monitoring, especially in the field of bolt preload monitoring at blades, yaw platforms and other locations of wind turbines. The principle of the method of acoustic time monitoring of bolt preload is to calculate the time difference of ultrasonic propagation inside the bolt when the bolt is loaded and unloaded, and calculate the corresponding bolt preload through the time difference, so as to realize the diagnosis of bolt condition. Before the ultrasound propagates to the bolt, an ultrasonic probe is needed. The piezoelectric ceramic piece in the ultrasonic probe is used to generate ultrasonic waves and receive reflected ultrasonic waves. In current ultrasonic technology, the probe body and piezoelectric ceramics of ultrasonic probes are mostly designed as an integrated structure. The integrated structure can reduce the installation workload before monitoring the bolts. However, for bolts with slots, the integrated ultrasonic probe must first grind the installation position of the bolts before installation. Only after grinding can the integrated ultrasonic probe be used to perform acoustic time measurement on the bolts. That is, the current integrated ultrasonic probe is not friendly to the acoustic time measurement of bolts with slots, and grinding the bolts is also time-consuming and labor-intensive. Moreover, even if some bolts with slots are grinded, they are not conducive to acoustic time measurement, which may lead to loss of measurement accuracy at the least and even make it impossible to use ultrasonic technology for measurement at the worst.

[0003] Based on the above shortcomings, the patent with publication number CN 218411510 U discloses an ultrasonic sensing device, wherein the ultrasonic probe disclosed therein includes a probe body of a split structure and a piezoelectric ceramic sheet. Before specific monitoring, the piezoelectric ceramic sheet can be placed in the notch of the bolt first, and then the probe body is adsorbed on the outer wall of the notch of the bolt. The probe body is provided with an electrical connection component (i.e., a pressure ring and an elastic probe) that can be adjusted along its axial direction. When the probe body is adsorbed on the bolt, the electrical connection between the probe body and the piezoelectric ceramic sheet is completed. The ultrasonic probe in this technical solution can objectively achieve the purpose of state monitoring of notched bolts, but compared with the integrated structure, the ultrasonic probe of the split structure leads to a large workload of pre-monitoring component installation when the number of bolts to be monitored is large, that is, the labor intensity of the operator is large. In addition, the ultrasonic probe of the split structure has a high probability of being lost at the work site because the ultrasonic probe and the piezoelectric ceramic sheet exist separately. At the same time, the elastic probe of the probe body has a high risk of being worn, bent, or even damaged and broken during use or transportation due to the lack of necessary protection. Utility Model Content

[0004] The ultrasonic probe designed in the present utility model can at least partially solve the above problems.

[0005] The utility model aims to provide an ultrasonic probe, comprising:

[0006] A probe body, wherein a first end surface of the probe body is formed with a receiving groove, and an electrical connector passes through the groove;

[0007] An ultrasonic sensitive unit, comprising a piezoelectric ceramic sheet, the piezoelectric ceramic sheet being electrically connected to the electrical connector, the ultrasonic sensitive unit having a retracted position at least partially accommodated in the accommodating groove and a protruding position at least partially protruding from a notch of the accommodating groove;

[0008] an elastic member, located in the accommodating groove and clamped between the ultrasonic sensitive unit and the groove bottom wall of the accommodating groove, so that the ultrasonic sensitive unit can be switched from the retracted position to the protruding position;

[0009] The fixing component is used to fix the probe body on the bolt to be monitored.

[0010] In some embodiments, the fixing component is a permanent magnetic ring, a first end surface of the permanent magnetic ring is fixedly connected to a first end surface of the probe body, and a central through hole of the permanent magnetic ring corresponds to a position of the ultrasonic sensitive unit.

[0011] In some embodiments, the ultrasonic sensitive unit also includes a protective cover, which is wrapped around the outer peripheral side of the piezoelectric ceramic sheet, and a flange extending radially outward is formed at one end of the protective cover close to the bottom wall of the accommodating groove, and the outer diameter of the flange is larger than the diameter of the central through hole of the permanent magnet ring.

[0012] In some embodiments, the end of the protective cover away from the bottom wall of the accommodating groove has a ceramic matching layer, and the piezoelectric ceramic sheet is attached to the inner end surface of the ceramic matching layer.

[0013] In some embodiments, the permanent magnetic ring is adhered to the first end surface of the probe body.

[0014] In some embodiments, the accommodating groove is filled with absorbing material.

[0015] In some embodiments, a sealing ring is provided between the flange and the groove wall of the accommodating groove.

[0016] In some embodiments, the probe body is also constructed with a channel filled with absorbing material, the inner port of the channel filled with absorbing material is connected to the accommodating space of the accommodating groove, the outer port is formed on the outer surface of the probe body, and an elastic shrinkage bag is assembled on the outer port.

[0017] In some embodiments, the elastic member is a coil spring, and the coil spring is a hollow tube. The positive and negative cables of the electrical connector pass through the hollow tube and are electrically connected to the positive and negative electrodes of the piezoelectric ceramic sheet.

[0018] The ultrasonic probe of the utility model:

[0019] The ultrasonic sensitive unit is placed in a receiving groove on the first end face of the probe body and can be switched between a retracted position and a protruding position, so that the ultrasonic probe in the utility model can be used for monitoring the preload of both the bolts to be monitored with slots and the bolts to be monitored without slots in an integrated structure, effectively reducing the installation workload of the monitoring operator and reducing the work intensity. At the same time, since the ultrasonic sensitive unit and the probe body in the utility model are an integrated assembly structure rather than a separate independent assembly structure, it can effectively reduce the probability of loss of components at the work site, and can also reduce the probability of wear or damage of electrical connectors during the use or transportation of components. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of an ultrasonic probe according to an embodiment of the utility model (from a frontal perspective).

[0021] Figure 2 yes Figure 1 Schematic diagram of the state after the ultrasonic probe is installed on the bolt to be monitored, and the bolt to be detected in the figure has an open groove.

[0022] Figure 3 It is a structural schematic diagram of an ultrasonic probe according to another embodiment of the utility model (from a frontal viewing angle).

[0023] In the figure:

[0024] 1. Probe body; 11. Accommodating groove; 12. Absorbing material filled flow channel; 13. Elastic shrink bag; 2. Ultrasonic sensitive unit; 21. Piezoelectric ceramic sheet; 22. Protective cover; 221. Flange; 23. Ceramic matching layer 3. Elastic part; 4. Fixing part; 100. Bolt to be monitored. DETAILED DESCRIPTION

[0025] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present invention will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. In the drawings, the thickness of regions and layers are exaggerated for clarity. The same reference numerals in the drawings represent the same or similar structures, and thus their detailed description will be omitted.

[0026] The described features, structures or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present invention. However, those skilled in the art will appreciate that the technical solution of the present invention may be practiced without one or more of the specific details, or other methods, components, materials, etc. may be used. In other cases, known structures, materials or operations are not shown or described in detail to avoid blurring the various aspects of the present invention.

[0027] The following example is an ultrasonic probe of the utility model. This example is only a part of the embodiments of the utility model, but the protection scope of the utility model is not limited to this. All other embodiments obtained by ordinary technicians in this field without creative work should be included in the protection scope of the utility model.

[0028] Please refer to Figures 1 to 3 According to an embodiment of the utility model, an ultrasonic probe is provided, specifically an integrated ultrasonic probe, which is specifically used to monitor the bolt preload force of wind turbine blades and yaw platforms, including:

[0029] A probe body 1, wherein a first end surface of the probe body 1 is formed with an accommodating groove 11, in which an electrical connector (not shown in the figure) passes. It can be understood that the electrical connector is, for example, a cable electrically connected to a corresponding ultrasonic generating device (such as an ultrasonic transducer, etc.), and the probe body 1 can specifically be a shell structure made of metal or plastic with a certain strength;

[0030] The ultrasonic sensitive unit 2 includes a piezoelectric ceramic sheet 21, and the piezoelectric ceramic sheet 21 is electrically connected to the electrical connector. The ultrasonic sensitive unit 2 has a retracted position at least partially accommodated in the accommodating groove 11 and a protruding position at least partially protruding from the notch of the accommodating groove 11. That is, in some cases, the ultrasonic sensitive unit 2 can be completely accommodated in the accommodating groove 11 when in the retracted position, and can be completely outside the accommodating groove 11 when in the protruding position. It can be understood that the ultrasonic sensitive unit 2 is a mature ultrasonic longitudinal wave transceiver in the industry, and its core component is the piezoelectric ceramic sheet 21, wherein the piezoelectric ceramic sheet 21 generates an ultrasonic signal through the excitation of an electric pulse signal, and at the same time, it can also receive the ultrasonic signal reflected back from the interface of the bolt 100 to be monitored, so as to realize the state monitoring (such as preload) of the bolt 100 to be monitored. As a relatively well-known technology, it will not be described here.

[0031] The elastic member 3 is located in the accommodating groove 11 and is clamped between the ultrasonic sensitive unit 2 and the bottom wall of the accommodating groove 11, so that the ultrasonic sensitive unit 2 can be switched from the retracted position to the protruding position;

[0032] The fixing component 4 is used to fix the probe body 1 on the bolt 100 to be monitored.

[0033] In this technical solution, the ultrasonic sensitive unit 2 is placed in the accommodating groove 11 on the first end face of the probe body 1 and can be switched between a retracted position and a protruding position, so that the ultrasonic probe in the utility model can be used for monitoring the preload of the bolts 100 to be monitored with slots and the bolts 100 to be monitored without slots in an integrated structure, effectively reducing the installation workload of the monitoring operator and reducing the work intensity. At the same time, since the ultrasonic sensitive unit 2 and the probe body 1 in the utility model are an integrated assembly structure rather than a separate independent assembly structure, it can effectively reduce the probability of loss of components at the work site, and can also reduce the probability of wear or damage of electrical connectors during the use or transportation of components.

[0034] It should be noted that the size of the aforementioned ultrasonic sensitive unit 2 should be compatible with the slot size of the bolt 100 to be monitored. The slot size should ensure that the protruding part of the ultrasonic sensitive unit 2 can be smoothly placed in the slot. When the slot size is not met, the slot should be expanded before installing the ultrasonic probe, such as by using a reaming device to expand or grind.

[0035] The aforementioned fixing component 4 can, for example, be provided with a corresponding snap-on connection component, a clamping component, etc. on the outside of the probe body 1, so as to achieve the purpose of reliably fixing the ultrasonic probe on the bolt 100 to be monitored. As a preferred embodiment, the fixing component 4 is a permanent magnetic ring, and the first end face of the permanent magnetic ring is fixedly connected to the first end face of the probe body 1, and the central through hole of the permanent magnetic ring corresponds to the position of the ultrasonic sensitive unit 2. It should be noted that, in general, the material of the bolt 100 to be monitored mostly contains magnetic materials such as iron. Therefore, the utility model utilizes this situation and implements the fixing component 4 with a permanent magnetic ring, so as to utilize the magnetic attraction of the permanent magnetic ring to adsorb and fix the bolt 100 to be monitored, which can significantly improve the installation efficiency of the ultrasonic probe. The aforementioned permanent magnetic ring can be fixed to the probe body 1 by bolting or snap-fitting, for example. When the material of the probe body 1 contains magnetic material, it can be fixed to the probe body 1 only by magnetic attraction. When the material of the probe body 1 does not contain magnetic material, as a preferred implementation method, the permanent magnetic ring is adhered to the first end face of the probe body 1, which has a simple structure and low implementation cost.

[0036] See Figure 3 As shown, in some embodiments, the ultrasonic sensitive unit 2 also includes a protective cover 22, the protective cover 22 is wrapped around the outer peripheral side of the piezoelectric ceramic sheet 21, and the end of the protective cover 22 close to the bottom wall of the accommodating groove 11 is formed with a flange 221 extending radially outward, and the outer diameter of the flange 221 is larger than the diameter of the central through hole of the permanent magnetic ring. In this way, the ultrasonic sensitive unit 2 can be reliably limited in the accommodating groove 11 by the permanent magnetic ring via the flange 221 of the protective cover 22, that is, the permanent magnetic ring in this technical solution can not only serve as a fixing component 4 to realize convenient fixation of the ultrasonic probe, but also exist as an axial limiter for the ultrasonic sensitive unit 2, thereby simplifying the structural design of the ultrasonic probe.

[0037] See also Figure 3 As shown, in some embodiments, the protective cover 22 has a ceramic matching layer 23 at one end away from the bottom wall of the accommodating groove 11, and the piezoelectric ceramic sheet 21 is bonded to the inner end surface of the ceramic matching layer 23. Specifically, the piezoelectric ceramic sheet 21 is glued to the inner end surface of the ceramic matching layer 23 to ensure reliable bonding between the two. The aforementioned ceramic matching layer 23 can be made of alumina. In this technical solution, the ceramic matching layer 23 is provided on the outer side of the piezoelectric ceramic sheet 21 to protect the piezoelectric ceramic sheet 21 and prevent the piezoelectric ceramic sheet 21 from being damaged by external forces. At the same time, the provision of the aforementioned ceramic matching layer 23 is also conducive to improving the signal transmission efficiency. It can be understood that the thickness of the ceramic matching layer 23 should match the frequency of the piezoelectric ceramic sheet 21.

[0038] In some embodiments, the accommodating groove 11 is filled with an absorbing material, and the absorbing material is specifically filled in the gap of the accommodating groove 11. The absorbing material can absorb external electromagnetic waves, thereby preventing external electromagnetic waves from interfering with ultrasonic waves, and ensuring the accuracy and reliability of ultrasonic sound monitoring. The aforementioned absorbing material can be made of solid material, but at this time, it should not fill the space of the accommodating groove 11, and it should ensure that the ultrasonic sensitive unit 2 has sufficient axial retraction space.

[0039] In a preferred embodiment, the aforementioned absorbing material is preferably a material in a fluid state, such as a silicone oil magnetic fluid absorbing material. In order to ensure that the absorbing material does not leak out of the accommodating groove 11, in a preferred embodiment, a sealing ring (not shown in the figure) is provided between the flange 221 and the groove wall of the accommodating groove 11. Figure 3As shown, in some embodiments, the probe body 1 is further structured with an absorbing material filled flow channel 12, the inner port of the absorbing material filled flow channel 12 is communicated with the accommodating space of the accommodating groove 11, the outer port is formed on the outer surface of the probe body 1, and an elastic shrink bag 13 is assembled on the outer port, and the elastic shrink bag 13 can be specifically made of elastic rubber, so that the elastic shrink bag 13 can form a buffer storage cavity for the absorbing material in the accommodating groove 11, when the bottom surface of the ultrasonic sensitive unit 2 is upward (that is, toward the probe body), the elastic shrink bag 13 can be formed into a buffer storage cavity for the absorbing material in the accommodating groove 11, and ... 1 side), that is, during the process of the ultrasonic sensitive unit 2 moving from the protruding position to the retracted position, the absorbing material filled in the accommodating groove 11 will flow through the aforementioned absorbing material filling flow channel 12 and be stored in the elastic contraction capsule 13, thereby preventing the problem of large retraction resistance of the ultrasonic sensitive unit 2 due to being filled with absorbing material. It can be understood that during the switching process of the ultrasonic sensitive unit 2 from the retracted position to the protruding position, the elastic contraction force of the elastic contraction capsule 13 will force the absorbing material temporarily stored therein to flow back and fill in the accommodating groove 11. It can be understood that the setting of the aforementioned absorbing material filling flow channel 12 should not interfere with the routing of the electrical connector of the probe body 1.

[0040] In another preferred embodiment, the elastic member 3 is a coil spring, and the coil spring is a hollow tube, and the positive and negative cables of the electrical connector pass through the hollow tube and are electrically connected to the positive and negative electrodes of the piezoelectric ceramic sheet 21. In this technical solution, the positive and negative cables of the electrical connector pass through the hollow tube of the coil spring, which can further simplify the structural design.

[0041] The following is a brief description of the principle of ultrasonic method for measuring bolt preload. It should be emphasized that the method of using ultrasonic sound timing principle to monitor bolt preload is well known to those skilled in the art, as follows:

[0042] According to the principle of acoustic elasticity, the speed of ultrasonic wave propagation will be affected by material stress, and the relationship between the two is shown in the following formula (1).

[0043] c=(1-kσ)c0 (1)

[0044] Where k is the acoustoelastic coefficient related to the bolt material; σ is the axial stress of the bolt; c0 is the speed of sound when there is no stress; and c is the speed of sound when there is stress.

[0045] The time difference of ultrasonic wave propagation in the bolt before and after the bolt is subjected to force is:

[0046]

[0047] Where L0 is the effective clamping length of the bolt; E is the Young's elastic modulus of the bolt material.

[0048]

[0049] Where A is the ultrasonic stress coefficient of the bolt. According to the relationship between stress and axial force, we can get:

[0050]

[0051] In the formula, F is the axial force on the bolt, and S is the effective area of ​​the middle section of the bolt. By measuring the time difference of the ultrasonic wave propagating in the bolt before and after the bolt is subjected to force, the tightening force of the bolt can be calculated. When the corresponding bolt sound is collected by the ultrasonic monitoring system, the bolt tightening force can be calculated by formula (4).

[0052] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An ultrasonic probe, characterized in that: include: A probe body (1), wherein a first end surface of the probe body (1) is formed with a receiving groove (11), and an electrical connector passes through the groove; An ultrasonic sensitive unit (2), comprising a piezoelectric ceramic sheet (21), the piezoelectric ceramic sheet (21) being electrically connected to the electrical connector, the ultrasonic sensitive unit (2) having a retracted position at least partially accommodated in the accommodating groove (11) and a protruding position at least partially protruding from a notch of the accommodating groove (11); an elastic member (3) located in the accommodating groove (11) and clamped between the ultrasonic sensitive unit (2) and the bottom wall of the accommodating groove (11), so that the ultrasonic sensitive unit (2) can be switched from the retracted position to the protruding position; A fixing component (4) is used to fix the probe body (1) on the bolt (100) to be monitored.

2. The ultrasonic probe according to claim 1, characterized in that: The fixing component (4) is a permanent magnetic ring, the first end surface of the permanent magnetic ring is fixedly connected to the first end surface of the probe body (1), and the central through hole of the permanent magnetic ring corresponds to the position of the ultrasonic sensitive unit (2).

3. The ultrasonic probe according to claim 2, characterized in that: The ultrasonic sensitive unit (2) further comprises a protective cover (22), the protective cover (22) being wrapped around the outer peripheral side of the piezoelectric ceramic sheet (21), and a flange (221) extending radially outward is formed at one end of the protective cover (22) close to the bottom wall of the accommodating groove (11), the flange (221) having an outer diameter greater than the diameter of the central through hole of the permanent magnet ring.

4. The ultrasonic probe according to claim 3, characterized in that: One end of the protective cover (22) away from the bottom wall of the accommodating groove (11) has a ceramic matching layer (23), and the piezoelectric ceramic sheet (21) is attached to the inner end surface of the ceramic matching layer (23).

5. The ultrasonic probe according to claim 2, characterized in that: The permanent magnetic ring is adhered to the first end surface of the probe body (1).

6. The ultrasonic probe according to claim 3, characterized in that: The accommodating groove (11) is filled with wave absorbing material.

7. The ultrasonic probe according to claim 6, characterized in that: A sealing ring is provided between the flange (221) and the groove wall of the accommodating groove (11).

8. The ultrasonic probe according to claim 6, characterized in that: The probe body (1) is also provided with a channel (12) filled with absorbing material, the inner port of the channel (12) filled with absorbing material is in communication with the accommodation space of the accommodation groove (11), the outer port is formed on the outer surface of the probe body (1), and an elastic shrink bag (13) is assembled on the outer port.

9. The ultrasonic probe according to claim 1, characterized in that: The elastic member (3) is a coil spring, and the coil spring is a hollow tube. The positive and negative cables of the electrical connector pass through the hollow tube and are electrically connected to the positive and negative electrodes of the piezoelectric ceramic sheet (21).

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