A bridge crack detection device

Abstract

This utility model relates to a bridge crack detection device, comprising: two connecting plates, with symmetrically distributed connecting frames between the two connecting plates, and sliding grooves respectively opened at both ends of the inner cavities of the two connecting frames; two sliding plates, with sliders fixedly connected to both ends of the two sliding plates, the sliders forming a friction sliding pair with the sliding grooves, so that the sliders remain stationary when no external force is applied; and transducers for crack detection are provided at the bottom of the two sliding plates. This utility model eliminates the need for the inspector to hold the transducers when they are placed on both sides of the crack on the bridge surface being inspected, avoiding the physical exertion of maintaining limb stability. At the same time, it effectively prevents the transducers from slight displacement or angular tilting caused by hand shaking, ensuring the relative position of the transducers and cracks is stable and avoiding the problem of detection accuracy deviation caused by hand shaking.

Description

Technical Field

[0001] This utility model relates to the field of bridge crack detection technology, specifically a bridge crack detection device. Background Technology

[0002] In the safety monitoring of concrete engineering projects such as bridges, building structures, and tunnels, crack width is a key indicator for assessing the structural health status, and its accurate measurement is directly related to the scientific nature of defect diagnosis and maintenance decisions. Crack detectors, as the core tool, typically work in conjunction with two transducers (such as ultrasonic transducers or laser transceivers): the two transducers are placed on opposite sides of the crack, and the actual width of the crack is calculated by detecting parameters such as the sound wave propagation time difference and laser projection offset (the measurement accuracy needs to reach ±0.05mm level to meet the requirements of refined monitoring).

[0003] The existing two transducers require the inspector to hold them with both hands and manually align them with reference positions on both sides of the crack. In actual inspection scenarios, holding them with both hands not only requires maintaining limb stability but also requires considering the relative position of the transducers and the crack. This operation is cumbersome and labor-intensive. Furthermore, when holding them with both hands, the transducers are prone to slight displacement or angular tilt due to natural hand tremors, thus affecting the accuracy of crack detection. Therefore, a new technical solution is needed to address this issue. Utility Model Content

[0004] The purpose of this utility model is to overcome the shortcomings of the existing technology, adapt to the needs of reality, and provide a bridge crack detection device to solve the technical problems of the current actual detection scenario, where holding the device with both hands not only requires maintaining limb stability, but also requires taking into account the relative position of the transducer and the crack, which is cumbersome and labor-intensive. Furthermore, when holding the device with both hands, the transducer is prone to slight displacement or angular tilt due to the natural shaking of the hands, thus affecting the accuracy of crack detection.

[0005] To achieve the purpose of this utility model, the technical solution adopted by this utility model is as follows: A bridge crack detection device is designed, comprising: Two connecting plates are provided, and symmetrically distributed connecting frames are provided between the two connecting plates. Sliding grooves are respectively opened at both ends of the inner cavities of the two connecting frames. Two sliding plates, each with a slider fixedly connected to both ends. The slider and the groove form a friction sliding pair, so that the slider remains stationary when no external force is applied. The bottom of each sliding plate is provided with a transducer for crack detection. The folding mechanism is located between the connecting plate and the connecting frame, allowing the connecting frame to switch between an unfolded and folded state. Folding reduces the size of the device and makes it easier to carry.

[0006] Preferably, the folding mechanism includes a connecting shaft rotatably connected between the two connecting plates via a damping bearing, and the connecting frame is fixedly connected to the outside of the connecting shaft.

[0007] Preferably, the connecting plate has an arc-shaped groove with an angle of 90°, and the center of the arc-shaped groove is collinear with the center of the connecting shaft. A screw is fixedly connected to one end of the connecting frame near the connecting plate, and the screw passes through the arc-shaped groove. A nut is threaded onto the outside of the screw on the outside of the connecting plate, and the size of the nut is larger than the size of the arc-shaped groove.

[0008] Preferably, a central plate is fixedly connected between the two connecting plates between the two connecting shafts, and the central plate is integrally formed of transparent acrylic material, with a central hole in the center of the central plate.

[0009] Preferably, a circular hole is provided in the middle of the slide plate, and a sleeve is fixedly connected to the slide plate at the top of the circular hole. The sleeve and the circular hole are positioned and matched in size. A connecting post is slidably connected inside the circular hole, and the transducer is fixedly connected to the bottom of the connecting post. A spring is provided between the top of the inner cavity of the sleeve and the connecting post.

[0010] Preferably, a limiting ring is fixedly connected to the outer side of the connecting column, the limiting ring is slidably connected in the circular hole, and the outer dimensions of the limiting ring are adapted to the inner dimensions of the circular hole. A fixing ring is slidably sleeved on the outer side of the connecting column, and the size of the fixing ring is larger than the size of the circular hole. A fixing bolt passes through the fixing ring, and the fixing bolt is threadedly screwed to the bottom surface of the slide plate.

[0011] Preferably, a wire hole is provided at the center of the top of the sleeve, and a wire is provided in the wire hole. One end of the wire passes through the connecting post and is electrically connected to the transducer, and the other end of the wire is electrically connected to the crack detector.

[0012] Preferably, the surface of the connecting frame is engraved with scale lines, and a pointer is fixedly connected to the slide plate. The arrow of the pointer is at a right angle, and the arrow of the pointer moves against the surface of the connecting frame.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows: This invention uses a friction sliding pair between the slide plate and the connecting frame for fixation. When the transducer is adjusted to a suitable position using the slide plate, it is placed on both sides of the crack on the bridge surface to be inspected. This eliminates the need for the inspector to hold the transducer by hand, avoiding the physical exertion of maintaining limb stability. Furthermore, the friction sliding pair formed by the slide plate and the groove remains stationary when there is no external force, effectively preventing minor displacement or angular tilting of the transducer caused by hand tremors. This ensures the relative position of the transducer and the crack remains stable, avoiding the problem of detection accuracy deviation caused by hand tremors. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the connection structure between the sliding plate, connecting post, and sleeve of this utility model; Figure 3 This is a cross-sectional structural diagram of the connection between the sliding plate, connecting column, and sleeve of this utility model.

[0015] In the diagram: 1. Connecting plate; 11. Connecting frame; 12. Slide groove; 13. Slide plate; 14. Slider; 2. Transducer; 21. Wire; 22. Connecting post; 3. Sleeve; 31. Wire hole; 32. Round hole; 4. Center plate; 41. Center hole; 5. Connecting shaft; 51. Arc groove; 52. Screw; 53. Nut; 6. Pointer; 61. Scale line; 7. Fixing ring; 71. Fixing bolt; 72. Limiting ring; 8. Spring. Detailed Implementation

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments: Example 1: A bridge crack detection device, see [link / reference] Figures 1 to 3 ,include: Two connecting plates 1, with symmetrically distributed connecting frames 11 between the two connecting plates 1, and sliding grooves 12 respectively opened at both ends of the inner cavities of the two connecting frames 11; Two sliding plates 13 are provided, and sliders 14 are fixedly connected to both ends of the two sliding plates 13. The sliders 14 and the slide groove 12 form a friction sliding pair, so that the sliders 14 remain stationary when no external force is applied. The bottom of the two sliding plates 13 is provided with transducers 2 for crack detection. A folding mechanism is provided between the connecting plate 1 and the connecting frame 11, enabling the connecting frame 11 to switch between an unfolded state and a folded state. Folding reduces the size of the device and makes it easier to carry. The folding mechanism includes a connecting shaft 5 that is rotatably connected between the two connecting plates 1 via a damping bearing, and the connecting frame 11 is fixedly connected to the outside of the connecting shaft 5.

[0017] During operation, the transducer 2 is fixed by the friction sliding pair between the slide plate 13 and the connecting frame 11. When the transducer 2 is adjusted to a suitable position with the help of the slide plate 13, it is placed on both sides of the crack on the bridge surface to be inspected. This eliminates the need for the inspector to hold the transducer, avoiding the physical exertion of maintaining limb stability. Furthermore, the friction sliding pair formed by the slider 14 and the groove 12 remains stationary when there is no external force, which can effectively prevent the transducer 2 from slight displacement or tilting due to hand tremors. This ensures the relative position of the transducer 2 and the crack is stable, avoiding the problem of detection accuracy deviation caused by hand tremors. In addition, the folding mechanism realizes the opening and folding switching of the connecting frame 11 through the damping bearing and the connecting shaft 5. After folding, the size of the equipment can be reduced, making it easy to carry and store, adapting to the needs of frequent equipment movement in bridge inspection scenarios, and further improving inspection efficiency.

[0018] For details, see Figure 1 The connecting plate 1 has an arc-shaped groove 51 with an angle of 90°, and the center of the arc-shaped groove 51 is collinear with the center of the connecting shaft 5. A screw 52 is fixedly connected to one end of the connecting frame 11 near the connecting plate 1, and the screw 52 passes through the arc-shaped groove 51. A nut 53 is threaded on the outside of the screw 52 on the outside of the connecting plate 1, and the size of the nut 53 is larger than the size of the arc-shaped groove 51. The arc-shaped groove 51 and the screw 52 can control the angle of unfolding and folding of the connecting frame 11, ensuring that the connecting frame 11 is placed horizontally after unfolding. After unfolding and folding, the nut 53 is rotated to contact the outside of the connecting plate 1, thereby limiting the connection plate 1 after unfolding and folding, thus improving the stability of the connecting frame 11 when unfolded for use and folded for storage.

[0019] Further, see Figure 1 A center plate 4 is fixedly connected between the two connecting plates 1 between the two connecting shafts 5. The center plate 4 is integrally formed of transparent acrylic material. A center hole 41 is opened in the center of the center plate 4. The transparent acrylic material allows the inspector to directly observe the relative position of the crack and the equipment. The center hole 41 serves as a visual reference point to help quickly align the center of the crack and avoid the defects of blind alignment caused by hand.

[0020] It is worth noting that, see Figure 3The slide plate 13 has a circular hole 32 in the middle. A sleeve 3 is fixedly connected to the slide plate 13 at the top of the circular hole 32. The sleeve 3 is positioned and sized to correspond with the circular hole 32. A connecting post 22 is slidably connected inside the circular hole 32. The transducer 2 is fixedly connected to the bottom of the connecting post 22. A spring 8 is provided between the top of the inner cavity of the sleeve 3 and the connecting post 22. The spring 8 allows the transducer 2 to float up and down with the slight undulations of the crack surface (such as concrete pitting or curved surfaces), ensuring that the transducer 2 always maintains stable contact with the detection surface. This avoids signal acquisition deviation caused by uneven detection surface. Furthermore, the elastic deformation of the spring 8 can absorb the slight vibration of the equipment during the detection process, reducing the direct impact of vibration on the transducer 2 and avoiding displacement or angular deviation caused by rigid connection, further improving the stability of the detection data.

[0021] It is worth noting that, see Figure 3 A limiting ring 72 is fixedly connected to the outer side of the connecting column 22. The limiting ring 72 is slidably connected inside the circular hole 32, and the external dimensions of the limiting ring 72 are adapted to the internal dimensions of the circular hole 32. A fixing ring 7 is slidably sleeved on the outer side of the connecting column 22, and the size of the fixing ring 7 is larger than the size of the circular hole 32. A fixing bolt 71 passes through the fixing ring 7, and the fixing bolt 71 is threadedly screwed to the bottom surface of the slide plate 13. The axial displacement range of the connecting column 22 is limited by the mutual cooperation between the limiting ring 72 and the circular hole 32, which prevents the transducer 2 from accidentally falling off when the spring 8 fails. It also makes it easy to disassemble the connecting column 22 from the circular hole 32, which facilitates the repair of the damaged spring 8 and transducer 2.

[0022] It is worth mentioning that, see Figure 3 The top center of the sleeve 3 has a wire hole 31, and a wire 21 is provided in the wire hole 31. One end of the wire 21 passes through the connecting post 22 and is electrically connected to the transducer 2. The other end of the wire 21 is electrically connected to the crack detector. The wire 21 is connected through the wire hole 31 at the top of the sleeve 3 and electrically connected to the transducer 2 through the inside of the connecting post 22. This avoids the wire 21 being exposed and rubbing against the detection surface. At the same time, the movement path of the wire 21 is decoupled from the floating displacement of the transducer 2, avoiding the positional displacement of the transducer 2 caused by the pulling of the wire 21, and ensuring the stability and reliability of signal transmission during the detection process. In bridge crack detection, transducer 2 converts electrical signals into ultrasonic waves, which are transmitted to the tested material such as concrete through a coupling agent (such as petroleum jelly). The ultrasonic waves propagate along the surface or inside the material. When the ultrasonic waves encounter the crack interface (the difference in acoustic impedance between air and solid), part of the signal is reflected and captured by the receiving transducer 2. When there is no crack, the sound wave reaches the receiving end directly, and the propagation time is short. When there is a crack, the sound wave needs to bypass the crack tip, and the propagation path becomes longer. The crack depth is calculated by the time difference (formula: depth = sound speed × time difference / 2).

[0023] It is worth mentioning that, see Figure 1 The surface of the connecting frame 11 is engraved with scale lines 61, and a pointer 6 is fixedly connected to the slide plate 13. The arrow of the pointer 6 is at a right angle, and the arrow of the pointer 6 moves against the surface of the connecting frame 11. Through the cooperation of the scale lines 61 on the surface of the connecting frame 11 and the pointer 6, the inspector can directly read the relative distance between the two transducers 2. The distance can be quickly adjusted to the preset detection distance without additional measuring tools, thereby improving the efficiency of crack detection.

[0024] In addition, all components designed in this utility model are general standard parts or components known to those skilled in the art. Their structure and principle can be learned by those skilled in the art through technical manuals or conventional experimental methods. Those skilled in the art can fully implement them, so there is no need to elaborate. The content protected by this utility model does not involve improvements to the internal structure and method.

[0025] The embodiments disclosed herein are preferred embodiments, but are not limited thereto. Those skilled in the art can readily grasp the spirit of this utility model based on the above embodiments and make different extensions and variations. However, as long as they do not depart from the spirit of this utility model, they are all within the protection scope of this utility model.

Claims

1. A bridge crack detection device, characterized in that, include: Two connecting plates (1), and symmetrically distributed connecting frames (11) are provided between the two connecting plates (1). Sliding grooves (12) are respectively opened at both ends of the inner cavity of the two connecting frames (11). Two slide plates (13), each end of which is fixedly connected to a slider (14). The slider (14) and the groove (12) form a friction sliding pair, so that the slider (14) remains stationary when no external force is applied. The bottom of each slide plate (13) is provided with a transducer (2) for crack detection. The folding mechanism is located between the connecting plate (1) and the connecting frame (11), so that the connecting frame (11) can switch between the unfolded state and the folded state. Folding reduces the size of the equipment and makes it easy to carry.

2. The bridge crack detection device as described in claim 1, characterized in that, The folding mechanism includes a connecting shaft (5) rotatably connected between the two connecting plates (1) via a damping bearing, and the connecting frame (11) is fixedly connected to the outside of the connecting shaft (5).

3. The bridge crack detection device as described in claim 2, characterized in that, The connecting plate (1) has an arc groove (51) with an angle of 90°. The center of the arc groove (51) is collinear with the center of the connecting shaft (5). The connecting frame (11) is fixedly connected to a screw (52) at one end near the connecting plate (1). The screw (52) passes through the arc groove (51). A nut (53) is threaded on the outside of the screw (52) on the connecting plate (1). The size of the nut (53) is larger than the size of the arc groove (51).

4. The bridge crack detection device as described in claim 2, characterized in that, A center plate (4) is fixedly connected between the two connecting plates (1) between the two connecting shafts (5), and the center plate (4) is integrally formed of transparent acrylic material, and a center hole (41) is opened in the center of the center plate (4).

5. The bridge crack detection device as described in claim 1, characterized in that, The slide plate (13) has a circular hole (32) in the middle. A sleeve (3) is fixedly connected to the slide plate (13) at the top of the circular hole (32). The sleeve (3) and the circular hole (32) are in the same position and are of the same size. A connecting post (22) is slidably connected inside the circular hole (32). The transducer (2) is fixedly connected to the bottom of the connecting post (22). A spring (8) is provided between the top of the inner cavity of the sleeve (3) and the connecting post (22).

6. The bridge crack detection device as described in claim 5, characterized in that, A limiting ring (72) is fixedly connected to the outside of the connecting post (22). The limiting ring (72) is slidably connected in the round hole (32), and the external dimensions of the limiting ring (72) are adapted to the internal dimensions of the round hole (32). A fixing ring (7) is slidably sleeved on the outside of the connecting post (22), and the size of the fixing ring (7) is larger than the size of the round hole (32). A fixing bolt (71) passes through the fixing ring (7), and the fixing bolt (71) is threadedly screwed to the bottom surface of the slide plate (13).

7. A bridge crack detection device as described in claim 5, characterized in that, The top center of the sleeve (3) is provided with a wire hole (31), and a wire (21) is provided in the wire hole (31). One end of the wire (21) passes through the connecting post (22) and is electrically connected to the transducer (2). The other end of the wire (21) is electrically connected to the crack detector.

8. The bridge crack detection device as described in claim 1, characterized in that, The surface of the connecting frame (11) is engraved with scale lines (61), and a pointer (6) is fixedly connected to the slide plate (13). The arrow of the pointer (6) is at a right angle, and the arrow of the pointer (6) moves against the surface of the connecting frame (11).

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