Railway device for bridge bottom detection

Abstract

The application discloses a track device for bridge bottom detection, comprising a plurality of track units and hinges, each track unit comprising a main pipe and a circular pipe connected with the main pipe, the main pipes of two connected track units being movably connected through the hinges, the plurality of track units being stacked up and down or unfolded into a V-shaped type through the hinges, the plurality of track units being used for clamping a bridge when the plurality of track units are unfolded into the V-shaped type, and the circular pipes of two connected track units located at two corners of the V-shaped type being connected through a transition section. The application designs cross-over inner and outer circular pipe structures, a transition section structure with a built-in spring for supporting and limiting a vehicle, and a hinge which can be pressed to be unlocked and automatically locked, a transition section with a built-in spring and a brake device, so as to realize switching among a folded storage state, a spreading state and a locked state of the track device.

Description

Technical Field

[0001] This invention relates to the field of bridge inspection technology, and in particular to a track device for inspecting the underside of bridges. Background Technology

[0002] Bridge aging, cracks, and other defects seriously endanger the lives of pedestrians and vehicles. Regular inspection is essential to ensure the safe use of bridges. Current methods mainly include manual inspection, inspection using bridge inspection vehicles, and inspection using drones. Manual inspection requires professionals to climb or be lifted to the bottom of the bridge for observation, which is time-consuming, labor-intensive, costly, inefficient, and poses safety hazards. Using bridge inspection vehicles is problematic because the large size of the inspection truss often obstructs traffic, severely impacting efficiency. Furthermore, the truss's adaptability is poor, making inspection difficult for bridges that are too high or too low. When using drones, the weight of the portable equipment is limited, continuous inspection time is too short, and the complex environment at the bottom of the bridge presents challenges in precise control and signal loss.

[0003] In summary, existing bridge underpass inspection technologies have limitations in their application scenarios. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a track device for bridge under-inspection. Through a hinge that can be unlocked by pressing and automatically locked, a transition section with a built-in spring, and a braking device, the track device supports and limits the inspection vehicle. The track device can switch between a folded storage state, an unfolded state, and a locked state.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] A track device for bridge underpass inspection includes multiple track units and hinges. Each track unit includes a main pipe and a circular tube connected to the main pipe. The main pipes of two connected track units are movably connected by a hinge. The hinges allow the multiple track units to be stacked vertically or unfolded into a U-shape. When the multiple track units are unfolded into a U-shape, they are used to clamp the bridge. The circular tubes of two connected track units located at two corners of the U-shape are connected by a transition section.

[0007] The circular tube includes an inner circular tube and an outer circular tube. Each track unit includes two inner circular tubes and two outer circular tubes symmetrically distributed around the main tube as the center line. The outer circular tubes are located outside the inner circular tubes. The end of the inner circular tube in each track unit that is close to the outer circular tube extends into the area enclosed by the two outer circular tubes. When multiple track units are unfolded into a U-shape, both ends of the inner circular tubes located on the lower straight line of the U-shape (excluding the edge) extend into the area enclosed by the two outer circular tubes. Adjacent inner circular tubes located at the two corners of the U-shape are connected by a transition section.

[0008] The hinge includes a hinge middle section, hinge side section one, and hinge side section two. Hinge side section one and hinge side section two are respectively attached to both sides of the hinge middle section. The hinge middle section is fixedly connected to a main pipe, and hinge side section one and hinge side section two are fixedly connected to another adjacent main pipe. The hinge middle section and hinge side section one and hinge side section two can rotate relative to each other, so that the two adjacent main pipes are arranged in a straight line, at a right angle, or stacked one on top of the other.

[0009] The hinge includes a hinge shaft and a spring. The middle section of the hinge includes a central square hole, and the first side section of the hinge includes a side square groove. The central square hole and the side square groove are directly connected. The hinge shaft includes a block segment. The thickness of the block segment is greater than the depth of the central square hole and less than the depth of the side square groove. A spring hole is provided at the center of the end face of the block segment. A spring is provided in the spring hole. The two ends of the spring abut against the bottom surface of the spring hole and the bottom surface of the side square groove, respectively. Under the action of the spring, the block segment can be limited to fit against the central square hole to restrict the relative rotation of the middle section of the hinge with the first and second side sections of the hinge. The block segment can overcome the action of the spring and be limited to fit against the side square groove to allow the middle section of the hinge to rotate relative to the first and second side sections of the hinge.

[0010] A linear bearing is installed on one end face of the second hinge side section. The hinge shaft includes a shaft section connected to the block section. The outer wall of the shaft section is fitted with the interior of the linear bearing.

[0011] It also includes a braking device located at the two corners of the U-shape. The braking device includes a brake pad and a caliper. The brake pad is fixedly installed on the hinge side section one or the hinge side section two. The caliper is fixedly installed on the main pipe connected to the middle section of the hinge. The caliper cooperates with the brake pad to lock or release.

[0012] It also includes a testing vehicle, which includes an installation platform, a testing device installed on the upper part of the installation platform, and a limiting device connected to the lower part of the installation platform. The limiting device slides and clamps the inner and outer circular tubes.

[0013] The limiting device has two sets, each set including two spaced-apart limiting devices. Each limiting device includes a connecting rod, a limiting wheel seat, and a limiting wheel. The connecting rod is connected to the lower end of the installation platform. Both ends of the connecting rod are rotatably connected to a limiting wheel via a limiting wheel seat. Each limiting wheel seat is rotatably connected to three limiting wheels. The limiting wheels of each set of limiting devices slide and clamp on the inner and outer sides and the upper side of the corresponding inner tube and the upper and lower sides and the outer side of the outer tube.

[0014] Multiple unfolded track units located at the bottom of the U-shape are in a straight line and form a space with the bottom surface of the bridge for the inspection vehicle to travel on. The inspection device faces upward to inspect the bridge.

[0015] The transition section is a hollow flexible tube with a supporting spring inside. The supporting spring causes the transition section to bend into an arc shape, and the outer diameter of the transition section is equal to that of the inner tube.

[0016] The beneficial effects of this invention are: a cross-overlapping inner and outer circular tube structure and a transition section structure with built-in springs are designed to detect the support limit of the vehicle; a hinge that can be pressed to unlock and automatically locked, a transition section with built-in springs, and a braking device are designed to realize the switching between the folded storage state, the unfolded state, and the locked state of the track device. Attached Figure Description

[0017] Figure 1 This is a perspective view of the invention after it has been folded and stored.

[0018] Figure 2 for Figure 1 Top view;

[0019] Figure 3 for Figure 2 Sectional view along the middle AA direction;

[0020] Figure 4 This is a schematic diagram of the invention unfolding at the bottom of a bridge;

[0021] Figure 5 for Figure 4 A diagram with the bridge removed;

[0022] Figure 6 for Figure 5 Enlarged view of point B in the middle;

[0023] Figure 7 for Figure 5 Enlarged view of point C in the middle;

[0024] Figure 8 This is a perspective view of the hinge of the present invention;

[0025] Figure 9 This is a cross-sectional view of the hinge of the present invention;

[0026] Figure 10 The explosion of the hinge of the present invention Figure 1 ;

[0027] Figure 11 The explosion of the hinge of the present invention Figure 2 ;

[0028] Figure 12 This is a schematic diagram of the detection vehicle moving on the track device in this invention;

[0029] Figure 13 for Figure 12 A partial schematic diagram;

[0030] Figure 14 for Figure 13 Enlarged view of point D in the middle;

[0031] Figure 15 This is a schematic diagram of the limiting wheel of the testing vehicle of the present invention;

[0032] Figure 16 This is a schematic diagram of the limiting wheel of the detection vehicle of the present invention traveling in the transition section;

[0033] Figure 17 This is a schematic diagram illustrating the process of unfolding and locking the folded track device under the bridge according to the present invention.

[0034] In the diagram: Hinge 1, Hinge middle section 11, Middle section connecting seat 111, Middle section outer hole 112, Middle section middle hole 113, Middle section square hole 114, Hinge side section one 12, Side section connecting seat one 121, Side section square groove 122, Hinge side section two 13, Side section connecting seat two 131, Side section round hole 132, Hinge shaft 14, Shaft section 141, Square section 142, Spring hole 1421, Spring 15, Linear bearing 16, Bearing section 161, Flange section 162, Main pipe 2, Inner round tube 3, Inner round tube connector 31, Outer round tube 4, Outer round tube connector 41, Transition section 5, Braking device 6, Brake pad 61, Caliper 62, Converter seat 63, Bridge 7, Inspection vehicle 8, Installation platform 81, Connecting column 811, Inspection device 82, Limiting device 83, Connecting rod 831, Limiting wheel seat 832, Limiting wheel 833. Detailed Implementation

[0035] The technical solution of the present invention will be further described below through embodiments and in conjunction with the accompanying drawings.

[0036] like Figures 1-17 As shown, a track device for bridge under-slope inspection includes an inspection vehicle 8, multiple track units, and a hinge 1. Each track unit includes a main pipe 2 and a circular pipe connected to the main pipe 2. The circular pipe includes an inner circular pipe 3 and an outer circular pipe 4. Each track unit includes two inner circular pipes 3 and two outer circular pipes 4 symmetrically distributed around the main pipe 2 as the center line. The outer circular pipes 4 are located outside the inner circular pipes 3. (Refer to...) Figure 1 , Figure 2 , Figure 7 The inner tube 3 is connected to the main tube 2 via the inner tube connector 31 on the side closest to the main tube 2, and the outer tube 4 is connected to the main tube 2 via the outer tube connector 41 on the side closest to the main tube 2.

[0037] Reference Figure 12 , Figure 13 , Figure 14The testing vehicle 8 includes a mounting platform 81, a testing device 82 mounted on the upper end of the mounting platform 81, and a limiting device 83 connected to the lower end of the mounting platform 81. The limiting device 83 is slidably clamped between two inner circular tubes 3 and two outer circular tubes 4.

[0038] There are two detection devices 82, symmetrically distributed, with the detection devices 82 facing upwards to detect the bridge 7. There are two sets of limiting devices 83, each set including two spaced-apart limiting devices 83. Each limiting device 83 includes a connecting rod 831, a limiting wheel seat 832, and a limiting wheel 833. The connecting rod 831 is connected to the lower end of the mounting platform 81, and the lower end of the mounting platform 81 is connected to the upper end of the connecting rod 831 through a connecting column 811.

[0039] Reference Figure 14 , Figure 15 Both ends of the connecting rod 831 are rotatably connected to a limiting wheel 833 through a limiting wheel seat 832. Each limiting wheel seat 832 is rotatably connected to three limiting wheels 833. The limiting wheel seat 832 is provided with three holes for the corresponding insertion of the limiting wheels 833. After the limiting wheels 833 are inserted, they are connected by a pin to achieve their own rotation.

[0040] Reference Figure 14 Each set of limiting devices 83 has a limiting wheel 833 that slides and clamps on the inner and outer sides and the upper side of the corresponding inner tube 3 and the upper and lower sides and the outer side of the outer tube 4. That is, the limiting wheel seat 832 clamped on the inner tube 3 is placed horizontally and the center limiting wheel 833 is on the upper side of the inner tube 3, and the limiting wheel seat 832 clamped on the outer tube 4 is placed vertically and the center limiting wheel 833 is on the outer side of the outer tube 4. Both the inner tube 3 and the outer tube 4 have three clamping points, which ensures that the inspection vehicle 8 will not tip over.

[0041] Among them, the connection point of the inner tube connector 31 at the inner tube 3 is relatively low, lower than the middle height of the inner tube 3, so as not to hinder the movement of the limit wheel 833 of the corresponding detection vehicle 8 on that side.

[0042] In each track unit, the inner tube 3 extends into the area enclosed by the two outer tubes 4 at one end; refer to Figure 7 The two ends of the inner tube 3 extend into the square horizontal space enclosed by the two adjacent outer tubes 4. This includes two outer tubes 4 connected to the same main tube 2 as the inner tube 3 and an outer tube 4 connected to another adjacent main tube 2. This structure ensures that the movement of the limiting wheel 833 of the detection vehicle 8 will not be interrupted, thus ensuring the continuity of movement.

[0043] Reference Figure 13The limiting wheels 833 of the inspection vehicle 8 can have several practical applications: ① Two limiting devices 83 are clamped between two inner tubes 3, while the other two limiting devices 83 are completely suspended (i.e., the limiting wheels 833 do not clamp the two outer tubes 4); ② Two limiting devices 83 are clamped between two inner tubes 3, while the other two limiting devices 83 are half-clamped between two outer tubes 4 and half-suspended (i.e., each outer tube 4 clamps three limiting wheels 833); ③ Two limiting devices 83 are clamped between two outer tubes 4, while the other two limiting devices 83 are completely suspended; ④ Two limiting devices 83 are clamped between two outer tubes 4, while the other two limiting devices 83 are half-clamped between two inner tubes 3 and half-suspended; ⑤ (Refer to...) Figure 16 Two limiting devices 83 clamp the two transition sections 5, with the two outer limiting devices 83 completely suspended. In addition, there are many other practical applications, all of which can be derived from... Figure 5 It is directly derived that by arranging the inner and outer circular tubes 3 and 4 with overlapping lengths at the hinge 1, the support and limit of the inspection vehicle 8 at the connection of the track unit can be ensured while ensuring the folding and storage of the track device, and the contact limit at the hinge 1 is not interrupted.

[0044] The main pipes 2 of two adjacent track units are movably connected by a hinge 1, which allows multiple track units to be stacked vertically or unfolded into a U-shape. (See reference...) Figure 1 When the track device is not in use, multiple track units can be stacked one on top of the other to reduce the volume and make it easier to store and carry.

[0045] Reference Figure 4 , Figure 5 When multiple track units unfold into a U-shape, they are used to clamp the bridge 7. The circular tubes of two connected track units located at the two corners of the U-shape are connected by a transition section 5. After unfolding into a U-shape, a wheeled trolley is used on the upper part of the bridge 7, with a weight placed inside the trolley. The track units on both sides used to clamp the bridge 7 and the trolley are connected by bolts. In this way, the entire track device is held in place by the trolleys on both sides of the bridge 7.

[0046] Reference Figure 8 , Figure 9 , Figure 10 , Figure 11The hinge 1 includes a hinge middle section 11, a hinge side section one 12, a hinge side section two 13, a hinge shaft 14, and a spring 15. The hinge side section one 12 and the hinge side section two 13 are respectively attached to both sides of the hinge middle section 11. The hinge middle section 11 is fixedly connected to a main pipe 2. A middle section connecting seat 111 is integrally formed on one side of the hinge middle section 11 for connecting the main pipe 2. The hinge side section one 12 and the hinge side section two 13 are fixedly connected to another adjacent main pipe 2. A side section connecting seat one 121 is integrally formed on one side of the hinge side section one 12, and a side section connecting seat two 131 is integrally formed on one side of the hinge side section two 13. The side section connecting seat one 121 and the side section connecting seat two 131 are jointly connected to a main pipe 2.

[0047] The hinge middle section 11, hinge side section one 12, and hinge side section two 13 can rotate relative to each other, allowing two adjacent main pipes 2 to be arranged in a straight line (e.g., Figure 7 ) or arranged at right angles (e.g. Figure 6 ) or stacked vertically (e.g.) Figure 1 ).

[0048] The hinge shaft 14 includes a block segment 142 and a shaft segment 141 connected to the block segment 142. Specifically, the shaft segment 141 and the block segment 142 are integrally formed. The shaft segment 141 is a cylinder and the block segment 142 is a cuboid.

[0049] The hinge middle section 11 includes a middle section outer hole 112, a middle section central hole 113, and a middle section square hole 114 arranged sequentially. The middle section outer hole 112 and the middle section central hole 113 are both circular holes. The diameter of the middle section outer hole 112 is larger than the diameter of the middle section central hole 113. The diameter of the middle section central hole 113 is approximately equal to the outer diameter of the shaft section 141. The shaft section 141 passes through the middle section outer hole 112 and the middle section central hole 113. The shape of the middle section square hole 114 matches that of the square section 142.

[0050] The hinge side section 12 includes a side section square groove 122, the shape of which matches the square section 142. The middle section square hole 114 and the side section square groove 122 are directly connected. The thickness of the square section 142 is greater than the depth of the middle section square hole 114 and less than the depth of the side section square groove 122. A spring hole 1421 is provided at the center of the end face of the square section 142. A spring 15 is provided in the spring hole 1421. The two ends of the spring 15 abut against the bottom surface of the spring hole 1421 and the bottom surface of the side section square groove 122, respectively.

[0051] A linear bearing 16 is installed on one end face of the hinge side section 13. The center of the hinge side section 13 is provided with a side section circular hole 132. The linear bearing 16 includes a bearing section 161 and a flange section 162 connected to each other. The outer wall of the shaft section 141 is fitted with the interior of the linear bearing 16. Specifically, the outer wall of the bearing section 161 matches the diameter of the side section circular hole 132. The flange section 162 abuts against one end face of the hinge side section 13. Through the design of the linear bearing 16, the shaft section 141 can move smoothly along the linear bearing 16.

[0052] Under normal conditions, the block segment 142 can be limited and fitted against the middle square hole 114 under the force of the spring 15 to restrict the relative rotation between the middle section 11 of the hinge and the first hinge side section 12 and the second hinge side section 13 (i.e., Figure 9 (When the block segment 142 in the middle section moves to the extreme position to the left, the block segment 142 fills the entire middle section square hole 114 and the part exceeding it is located in the side section square groove 122. In this way, the hinge side section 12 is also restricted and cannot move relative to the hinge middle section 11. At this time, the angle between each main pipe 2 cannot be adjusted.

[0053] Press the shaft section 141 to the right until it reaches its limit position to obtain the desired result. Figure 9 In the indicated state, the block segment 142 can overcome the force of the spring 15 and be confined to the side segment square groove 122, allowing the hinge middle section 11 to rotate relative to the hinge side section 12 and hinge side section 2 13. At this time, the block segment 142 is completely located within the side segment square groove 122, and the middle segment square hole 114 is completely unrestricted. The hinge middle section 11 and hinge side section 12 can rotate relative to each other, thereby adjusting the angle between the various main pipes 2. When the desired angle is reached, the shaft segment 141 is no longer pressed. The shaft segment 141 returns to its original position and locks to the left under the force of the spring 15, and the hinge middle section 11 and hinge side section 12 can no longer rotate relative to each other. By rotating the block segment 142 180°, it can still cooperate with the side segment square groove 122 and the middle segment square hole 114 to achieve 0° and 180° locking.

[0054] exist Figure 5 Rotating them 180° relative to each other in this state allows the two main tubes to be pressed together and locked in a stacked state.

[0055] When multiple track units unfold into a U-shape, both ends of the inner circular tube 3 located on the lower straight line of the U-shape (excluding the edge) extend into the area enclosed by the two outer circular tubes 4. Refer to the same explanation above regarding the positional relationship between the inner circular tube 3 and the outer circular tube 4. The adjacent inner circular tubes 3 located at the two corners of the U-shape are connected by a transition section 5.

[0056] The transition section 5 is a hollow flexible tube with a supporting spring inside. The supporting spring allows the transition section 5 to bend into an arc shape. The outer diameter of the transition section 5 is equal to that of the inner circular tube 3. The transition section 5 is a commercially available component and will not be described in detail here. The transition section 5 can be flexibly unfolded, creating a near-circular curved slide, while also providing support and limiting for the inspection vehicle 8 within the transition section 5.

[0057] Reference Figure 6 The track device also includes braking devices 6 located at the two corners of the U-shape (i.e., the junction of the vertical and horizontal sections of the U-shape). The braking devices 6 include brake pads 61 and calipers 62. The brake pads 61 are fixedly installed on hinge side section 12 or hinge side section 2 13 via a conversion seat 63. The calipers 62 are fixedly installed on the main pipe 2 connected to the middle section 11 of the hinge. The calipers 62 cooperate with the brake pads 61 to lock or release the load. The braking devices 6 are also existing products and can be air brakes, cable brakes, etc. Through the braking devices 6, the hinge 1 at the transition section 5 is tightened, thus transitioning from a flexible state with variable angles to a locked state with fixed angles. The braking devices 6 tighten the track units on both sides of the transition section 5, resisting wind force and preventing swaying.

[0058] The adapter 63 provides a mounting base for the brake pad 61. The adapter 63 is mounted on the hinge 1, and during installation, the hinge shaft 14 of the hinge 1 is pressed down, placing it in a fully unlocked 360° state. This allows the transition section 5 to adapt to different angles to the width of the bridge 7. When the brake device 6 engages, the angle between the track units on both sides of the transition section 5 is fixed. The brake pad 61 is mounted on the adapter 63, and staggered threaded holes ensure sufficient working space for the screwdriver.

[0059] Reference Figure 4 The multiple unfolded track units located at the bottom of the U-shape are in a straight line and form a space for the inspection vehicle 8 to travel along the bottom surface of the bridge 7. The track device can provide support and limit for the inspection vehicle 8, so that the inspection vehicle 8 can travel along the space to carry out inspection.

[0060] like Figure 17 The diagram shows three states of the track device in its folded state, unfolded and locked at the bottom of bridge 7. At point A, the folded track device is prepared. At point B, a steel cable is lowered and transported from under the bridge to point A using equipment such as a drone. The steel cable is connected to the head of the track device via a hook. After connection, the steel cable is in the following state: Figure 17 As shown in Figure a. The track unit is lowered from point A. During the lowering process, it is converted into a rigid track state via hinge 1. During the lowering phase, the track unit hangs down naturally, while the straight section and transition section 5 remain flexible. After the connection is completed, the state is as shown. Figure 17As shown in b, the steel cable at end B retracts and pulls up the track unit. During the pulling process, the structure of the bottom track unit of the U-shape will naturally lock flat due to the mating surfaces, forming a rigid track. At this time, the drooping sections on both sides of the U-shape and the straight section at the bottom of the U-shape all form rigid tracks. The braking device 6 is activated to lock the track units at both ends of the transition section 5. The final state is as shown in b. Figure 17 As shown in c.

[0061] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A track device for bridge underpass inspection, characterized in that: It includes multiple track units and hinges (1). Each track unit includes a main tube (2) and a circular tube connected to the main tube (2). The main tubes (2) of two connected track units are movably connected by hinges (1). Multiple track units can be stacked or unfolded into a U-shape through hinges (1). When multiple track units are unfolded into a U-shape, they are used to clamp the bridge (7). The circular tubes of two connected track units located at the two corners of the U-shape are connected by transition sections (5). The circular tube includes an inner circular tube (3) and an outer circular tube (4). Each track unit includes two inner circular tubes (3) and two outer circular tubes (4) symmetrically distributed with the main tube (2) as the center line. The outer circular tubes (4) are located outside the inner circular tubes (3). The end of the inner circular tube (3) in each track unit that is close to the outer circular tube (4) extends into the area enclosed by the two outer circular tubes (4). When multiple track units are unfolded into a U-shape, both ends of the inner circular tubes (3) located on the lower straight line of the U-shape (excluding the edge) extend into the area enclosed by the two outer circular tubes (4). The adjacent inner circular tubes (3) located at the two corners of the U-shape are connected by a transition section (5). It also includes a testing vehicle (8), which includes an installation platform (81), a testing device (82) installed on the upper end of the installation platform (81), and a limiting device (83) connected to the lower end of the installation platform (81). The limiting device (83) is slidably clamped between the inner tube (3) and the outer tube (4).

2. The track device for bridge under-slope detection as described in claim 1, characterized in that: The hinge (1) includes a hinge middle section (11), a hinge side section one (12) and a hinge side section two (13). The hinge side section one (12) and the hinge side section two (13) are respectively attached to the two sides of the hinge middle section (11). The hinge middle section (11) is fixedly connected to a main pipe (2). The hinge side section one (12) and the hinge side section two (13) are fixedly connected to another adjacent main pipe (2). The hinge middle section (11) and the hinge side section one (12) and the hinge side section two (13) can rotate relative to each other so that the two adjacent main pipes (2) are arranged in a straight line, at right angles, or stacked one on top of the other.

3. The track device for bridge under-slope detection as described in claim 2, characterized in that: The hinge (1) includes a hinge shaft (14) and a spring (15). The middle section (11) of the hinge includes a middle section square hole (114), and the side section (12) of the hinge includes a side section square groove (122). The middle section square hole (114) and the side section square groove (122) are directly connected. The hinge shaft (14) includes a block section (142). The thickness of the block section (142) is greater than the depth of the middle section square hole (114) and less than the depth of the side section square groove (122). A spring hole (1421) is provided at the center of the end face of the block section (142). The spring hole (1421) contains... A spring (15) is provided, with its two ends abutting the bottom surface of the spring hole (1421) and the bottom surface of the side section square groove (122) respectively. Under the action of the spring (15), the square section (142) can be limited to fit against the middle section square hole (114) to restrict the relative rotation of the middle section of the hinge (11) with the first side section of the hinge (12) and the second side section of the hinge (13). The square section (142) can overcome the action of the spring (15) and be limited to fit against the side section square groove (122) so that the middle section of the hinge (11) can rotate relative to the first side section of the hinge (12) and the second side section of the hinge (13).

4. The track device for bridge under-slope detection as described in claim 3, characterized in that: A linear bearing (16) is installed on one end face of the hinge side section 2 (13), and the hinge shaft (14) includes a shaft section (141) connected to the block section (142). The outer wall of the shaft section (141) is fitted with the interior of the linear bearing (16).

5. The track device for bridge under-slope detection as described in claim 2, characterized in that: It also includes a braking device (6) located at the two corners of the U-shape. The braking device (6) includes a brake pad (61) and a caliper (62). The brake pad (61) is fixedly installed on the hinge side section one (12) or the hinge side section two (13). The caliper (62) is fixedly installed on the main pipe (2) connected to the hinge middle section (11). The caliper (62) cooperates with the brake pad (61) to lock or release.

6. The track device for bridge under-slope detection as described in claim 1, characterized in that: The limiting device (83) has two sets. Each set of limiting devices (83) includes two spaced-apart limiting devices (83). Each limiting device (83) includes a connecting rod (831), a limiting wheel seat (832), and a limiting wheel (833). The connecting rod (831) is connected to the lower end of the mounting platform (81). Both ends of the connecting rod (831) are rotatably connected to a limiting wheel (833) through a limiting wheel seat (832). Each limiting wheel seat (832) is rotatably connected to three limiting wheels (833). The limiting wheels (833) of each set of limiting devices (83) are slidably clamped on the inner and outer sides and the upper side of the corresponding inner tube (3) and the upper and lower sides and the outer side of the outer tube (4).

7. A track device for bridge under-surface detection as described in claim 1, characterized in that: Multiple unfolded track units located at the bottom of the U-shape are in a straight line and form a space for the inspection vehicle (8) to travel on the bottom surface of the bridge (7). The inspection device (82) faces upward to inspect the bridge (7).

8. The track device for bridge under-slope detection as described in claim 1, characterized in that: The transition section (5) is a hollow flexible tube. A support spring is installed inside the transition section (5). The support spring makes the transition section (5) bend into an arc shape. The outer diameter of the transition section (5) is equal to that of the inner tube (3).

Images