Engineering deep foundation pit water level monitoring device

Abstract

The utility model relates to the technical field of water level monitoring devices, in particular to an engineering deep foundation pit water level monitoring device which comprises a moving control assembly and a position adjusting assembly, the front end of the moving control assembly is fixedly connected with a launching control assembly, and the lower end of the position adjusting assembly is provided with a position detecting assembly. An auxiliary detection assembly is mounted on the inner side of the position detection assembly and comprises a bearing rotating roller, extension columns are fixedly connected to the left side and the right side of the bearing rotating roller correspondingly, the outer sides of the extension columns are rotationally connected to the inner sides of fixed shaft holes through bearings, the fixed shaft holes are formed in the inner sides of movable plates, and limiting rail bars are fixedly connected to the front ends and the rear ends of the movable plates correspondingly; according to the device, a worker does not need to directly enter water to install equipment, so that the operation risk is reduced, the safety of the worker is ensured, and the accuracy and convenience of measurement are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of water level monitoring devices, and particularly relates to a water level monitoring device for an engineering deep foundation pit. Background Technique

[0002] An engineering deep foundation pit refers to a large-scale earthwork project excavated in a building project for constructing an underground structure. Its depth usually exceeds five meters and sometimes even reaches dozens of meters. The construction of a deep foundation pit needs to consider complex geological conditions, groundwater level control, support structure design, and the safety of the surrounding environment to ensure the stability of the foundation pit during construction, prevent collapse and deformation, and at the same time reduce the impact on surrounding buildings and underground pipelines;

[0003] An engineering deep foundation pit water level monitoring device is a device used to monitor the change of the underground water level in a deep foundation pit in real time. It can accurately measure the height of the underground water level and transmit the data to the monitoring system in real time. Through this device, construction personnel can timely grasp the water level dynamics in the foundation pit, so as to take effective precipitation or drainage measures to ensure the safety and stability of the foundation pit construction and prevent problems such as foundation pit collapse or damage to the surrounding environment caused by the change of the underground water level;

[0004] The engineering deep foundation pit water level monitoring device needs to be installed inside the water because only when it is directly placed in the water can it accurately and real-time measure the height and change of the underground water level. This installation method can avoid surface interference factors and ensure the accuracy of the monitoring data, thus providing a basis for drainage and precipitation measures during the foundation pit construction process and ensuring the stability and construction safety of the foundation pit. For example, an immersion type water level gauge, a device commonly used for deep foundation pit water level monitoring, uses the principle of hydrostatic pressure to measure the water level change;

[0005] The slopes of some engineering deep foundation pits are relatively steep and the water levels are relatively deep. Since it is necessary to detect the height and depth of the water level, the engineering deep foundation pit water level monitoring device needs to be installed inside the water. During the process of installing the engineering deep foundation pit water level monitoring device inside the water by the staff, there is a certain danger. Therefore, an engineering deep foundation pit water level monitoring device is proposed for the above problems. Content of the Utility Model

[0006] The purpose of the utility model is to provide an engineering deep foundation pit water level monitoring device to solve the problem that the slopes of some engineering deep foundation pits are relatively steep and the water levels are relatively deep, and there is a certain danger during the process of installing the engineering deep foundation pit water level monitoring device inside the water by the staff.

[0007] To achieve the above purpose, the utility model provides the following technical solutions:

[0008] An engineering deep foundation pit water level monitoring device includes a mobile control component and a position adjustment component. A water control component is fixedly connected to the front end of the mobile control component. A position detection component is installed at the lower end of the position adjustment component. An auxiliary detection component is installed inside the position detection component. The auxiliary detection component includes a load-bearing rotating roller. Extension columns are fixedly connected to both the left and right sides of the load-bearing rotating roller. The outer sides of the extension columns are rotationally connected inside a fixed shaft hole through bearings. The fixed shaft hole is opened inside a movable plate. Limiting rail bars are fixedly connected to both the front end and the rear end of the movable plate. A spring is fixedly connected to the bottom end of the movable plate. The position detection component includes a top plate. A pressure sensor and a frame are fixedly connected to the bottom end of the top plate. A vertical groove is opened inside the frame. A blocking column is fixedly connected to the inner side of the frame near the lower end. A weight is fixedly connected to the bottom end of the frame. A laser rangefinder is fixedly connected to the bottom end of the weight. The limiting rail bars are slidably connected inside the vertical groove. The bottom end of the spring is fixedly connected to the inner side of the frame.

[0009] As a further optimized content of the present utility model, wherein: the mobile control component includes a counterweight block. A mobile vehicle is fixedly connected to the bottom end of the counterweight block. An installation groove is opened at the front end of the mobile vehicle. A guiding column is fixedly connected inside the installation groove. An integrated controller is fixedly connected to the right side of the counterweight block. The integrated controller, the pressure sensor, and the laser rangefinder are electrically connected.

[0010] As a further optimized content of the present utility model, wherein: the position adjustment component includes an electric telescopic rod. A U-shaped plate is fixedly connected to the top end of the electric telescopic rod. The bottom end of the electric telescopic rod is fixedly connected to the lower end of the guiding column. A sliding hole is opened inside the U-shaped plate. The inner side of the sliding hole of the U-shaped plate is slidably connected to the outer side of the guiding column. The U-shaped plate is electrically connected to the integrated controller.

[0011] As a further optimized content of the present utility model, wherein: a first rotating arm is rotatably connected inside the U-shaped plate. A fixed plate is rotatably connected to the lower end of the first rotating arm. Shaft columns are fixedly connected to both the left and right sides of the fixed plate. The outer sides of the shaft columns are rotatably connected to a second rotating arm. Shaft columns are rotatably connected to both the front end and the rear end of the second rotating arm. One side of the rear shaft column is fixedly connected inside the installation groove.

[0012] As a further optimized content of the present utility model, wherein: a spherical groove is opened at the lower end of the fixed plate. The inner side of the spherical groove of the fixed plate is in fit with the outer side of a spherical block. A vertical rod is fixedly connected to the bottom end of the spherical block. Spherical blocks are fixedly connected to both the top end and the bottom end of the vertical rod. The outer side of the lower spherical block is in fit with the inner side of the spherical groove opened on the top plate.

[0013] As a further optimized content of the present utility model, wherein: the water discharge control component includes a wire dispenser, the rear end of the wire dispenser is fixedly connected to the front end of the mobile vehicle, a counterweight cone is fixedly connected to the bottom end of the lead wire of the wire dispenser, the lead wire of the wire dispenser passes through the inside of the wire passing hole, the outer side of the lead wire of the wire dispenser is in contact with the outer side of the roller, the roller is rotatably connected to the inside of the ear seat, the ear seat is fixedly connected to the inside of the wire passing hole, and the wire passing hole is opened in the inside of the buoyancy plate.

[0014] As a further optimized content of the present utility model, wherein: the outer side of the load-bearing roller near the upper end is in contact with the lead wire of the wire dispenser, the bottom end of the movable plate is in contact with the top end of the stop post, and there is a distance between the top end of the movable plate and the bottom end of the pressure sensor.

[0015] Compared with the prior art, the beneficial effects of the present utility model are:

[0016] In the present utility model, through the provided position adjustment component, water discharge control component, auxiliary detection component and position detection component, the device does not require workers to directly enter the water to install the equipment, reducing the operation risk and ensuring the safety of personnel. Through precise mechanical transmission and feedback control system, the accuracy and convenience of measurement are improved, the practicability and reliability of the device are enhanced, and at the same time, the measurement points can be flexibly adjusted, expanding the measurement range. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of the overall structure of the present utility model;

[0018] Figure 2 is a schematic diagram of the structure of the mobile control component of the present utility model;

[0019] Figure 3 is a schematic diagram of the sectional structure of the position adjustment component of the present utility model;

[0020] Figure 4 is an exploded schematic diagram of the position adjustment component of the present utility model;

[0021] Figure 5 is a schematic diagram of the structure of the wire dispenser of the present utility model;

[0022] Figure 6 is a schematic diagram of the structure of the counterweight cone of the present utility model;

[0023] Figure 7 is a schematic diagram of the sectional structure of the buoyancy plate of the present utility model;

[0024] Figure 8 is for the present utility model Figure 7 schematic diagram of the structure at position A;

[0025] Figure 9It is a schematic diagram of the cutaway structure of the position detection assembly of the utility model;

[0026] Figure 10 This is a schematic diagram of the structure of the laser rangefinder of the utility model;

[0027] Figure 11 For this utility model Figure 10 Schematic diagram of the structure at B;

[0028] Figure 12 It is a schematic diagram of the cutaway structure of the auxiliary detection component of the utility model.

[0029] In the figure: 1, mobile control assembly; 11, counterweight; 12, mobile vehicle; 13, placement groove; 14, guide column; 15, integrated controller;

[0030] 2. Position adjustment assembly; 21. Electric telescopic rod; 22. U-shaped plate; 23. First rotating arm; 24. Fixed plate; 25. Second rotating arm; 26. Shaft column; 27. Ball block; 28. Vertical rod;

[0031] 3. Launch control assembly; 31. Wire release device; 32. Ear seat; 33. Counterweight cone block; 34. Buoyancy plate; 35. Roller; 36. Threading hole;

[0032] 4. Auxiliary detection components; 41. Load-bearing roller; 42. Extension column; 43. Fixed shaft hole; 44. Limit rail; 45. Spring; 46. Movable plate;

[0033] 5. Position detection component; 51. Top plate; 52. Pressure sensor; 53. Frame; 54. Vertical groove; 55. Stop column; 56. Weight block; 57. Laser rangefinder. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0035] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0036] See alsoFigure 1-12 , the present utility model provides a technical solution:

[0037] An engineering deep foundation pit water level monitoring device, including a mobile control component 1 and a position adjustment component 2. A water inlet control component 3 is fixedly connected to the front end of the mobile control component 1. A position detection component 5 is installed at the lower end of the position adjustment component 2. An auxiliary detection component 4 is installed inside the position detection component 5. The auxiliary detection component 4 includes a load-bearing roller 41. Extension columns 42 are fixedly connected to both the left and right sides of the load-bearing roller 41. The outer sides of the extension columns 42 are rotatably connected to the inside of a fixed shaft hole 43 through bearings. The fixed shaft hole 43 is opened inside a movable plate 46. Limiting rail bars 44 are fixedly connected to both the front end and the rear end of the movable plate 46. A spring 45 is fixedly connected to the bottom end of the movable plate 46. The position detection component 5 includes a top plate 51. A pressure sensor 52 and a frame 53 are fixedly connected to the bottom end of the top plate 51. A vertical groove 54 is opened inside the frame 53. A stop post 55 is fixedly connected to the inside of the frame 53 near the lower end. A weight block 56 is fixedly connected to the bottom end of the frame 53. A laser rangefinder 57 is fixedly connected to the bottom end of the weight block 56. The limiting rail bars 44 are slidably connected to the inside of the vertical groove 54. The bottom end of the spring 45 is fixedly connected to the inside of the frame 53.

[0038] As a further implementation of this solution, the mobile control component 1 includes a counterweight block 11. A mobile vehicle 12 is fixedly connected to the bottom end of the counterweight block 11. An installation groove 13 is opened at the front end of the mobile vehicle 12. A guide post 14 is fixedly connected to the inside of the installation groove 13. An integrated controller 15 is fixedly connected to the right side of the counterweight block 11. The integrated controller 15, the pressure sensor 52, and the laser rangefinder 57 are electrically connected. Through the above settings, this structural design enables the device to achieve electrical connection through the integrated controller 15, the pressure sensor 52, and the laser rangefinder 57, facilitating signal transmission and processing, and providing a basis for subsequent measurement and feedback control;

[0039] As a further implementation of this solution, the position adjustment component 2 includes an electric telescopic rod 21. A U-shaped plate 22 is fixedly connected to the top end of the electric telescopic rod 21. The bottom end of the electric telescopic rod 21 is fixedly connected to the lower end of the guide post 14. A sliding hole is opened inside the U-shaped plate 22. The inside of the sliding hole of the U-shaped plate 22 is slidably connected to the outside of the guide post 14. The U-shaped plate 22 is electrically connected to the integrated controller 15. Through the above settings, precise control of the lifting action of the U-shaped plate 22 is achieved, providing power and control basis for driving other components by the U-shaped plate 22 subsequently;

[0040] As a further implementation of this solution, a first rotating arm 23 is rotatably connected to the inner side of the U-shaped plate 22. The lower end of the first rotating arm 23 is rotatably connected to a fixing plate 24. Both the left and right sides of the fixing plate 24 are fixedly connected with shaft columns 26. The outer sides of the shaft columns 26 are rotatably connected to a second rotating arm 25. The front end and the rear end of the second rotating arm 25 are both rotatably connected to the shaft column 26. One side of the rear shaft column 26 is fixedly connected to the inner side of the placement groove 13. Through the above settings, the counterweight cone 33 can move along a predetermined trajectory, expanding the measurement range and improving the flexibility and accuracy of the device in adjusting the measurement point;

[0041] As a further implementation of this solution, a spherical groove is opened at the lower end of the fixing plate 24. The inner side of the spherical groove of the fixing plate 24 is in contact with the outer side of the spherical block 27. The bottom end of the spherical block 27 is fixedly connected with a vertical rod 28. The top end and the bottom end of the vertical rod 28 are both fixedly connected with the spherical block 27. The outer side of the lower spherical block 27 is in contact with the inner side of the spherical groove opened on the top plate 51. Through the above settings, the design of the spherical groove enables the spherical block 27 to rotate flexibly between the fixing plate 24 and the top plate 51. With the fixed connection of the vertical rod 28, the stability and verticality of the counterweight cone 33 during movement are ensured, further improving the accuracy of measurement;

[0042] As a further implementation of this solution, the underwater control assembly 3 includes a wire reel 31. The rear end of the wire reel 31 is fixedly connected to the front end of the mobile vehicle 12. The bottom end of the lead wire of the wire reel 31 is fixedly connected with a counterweight cone 33. The lead wire of the wire reel 31 passes through the inner side of the wire passing hole 36. The outer side of the lead wire of the wire reel 31 is in contact with the outer side of the roller 35. The roller 35 is rotatably connected to the inner side of the ear seat 32. The ear seat 32 is fixedly connected to the inner side of the wire passing hole 36. The wire passing hole 36 is opened in the inner side of the buoyancy plate 34. Through the above settings, due to the buoyancy of the buoyancy plate 34, the buoyancy plate 34 floats on the water surface, facilitating the measurement of the height of the buoyancy plate 34 by the laser rangefinder 57. At the same time, the contact between the wire and the roller 35 and the rotational connection of the roller 35 in the ear seat 32 reduce the friction when the lead wire moves, enabling the counterweight cone 33 to move more smoothly, improving the operation efficiency of the device and the reliability of measurement;

[0043] As a further implementation of this solution, the outer side of the load-bearing roller 41 near the upper end is in contact with the lead wire of the wire reel 31. The bottom end of the movable plate 46 is in contact with the top end of the stop post 55. There is a gap between the top end of the movable plate 46 and the bottom end of the pressure sensor 52. Through the above settings, the auxiliary detection assembly 4 can detect whether the counterweight cone 33 reaches the bottom of the water, and thus detect the water level based on the distance between the counterweight cone 33 and the buoyancy plate 34, providing key data support for measuring the water level and enhancing the accuracy and convenience of the device measurement.

[0044] Workflow: When the counterweight cone 33 is placed inside the water, the entire device is moved to the shore of the engineering deep foundation pit by the moving vehicle 12. The device is detected for levelness by an existing level, and adjusted to a level state. Then, the horizontal position of the counterweight cone 33 is adjusted. The electric telescopic rod 21 is started to drive the U-shaped plate 22 to lift and lower. When the U-shaped plate 22 moves downward, the horizontal distance between the counterweight cone 33 and the moving vehicle 12 becomes farther. The U-shaped plate 22 slides inside the guide post 14, and the U-shaped plate 22 drives the first rotating arm 23 to rotate. The first rotating arm 23 rotates to push the front end of the shaft column 26 to rotate around the rear end of the shaft column 26. The shaft column 26 drives the second rotating arm 25 to rotate. The shaft column 26 rotates inside the fixed plate 24, thereby driving the fixed plate 24 to displace. During the displacement of the fixed plate 24, under the action of the weight of the weight block 56, the laser rangefinder 57 remains facing downward at this time. At this time, the upper ball block 27 rotates inside the fixed plate 24, and the lower ball block 27 rotates inside the top plate 51. This setting can ensure that the end of the laser rangefinder 57 can face the buoyancy plate 34, laying a foundation for determining the position of the buoyancy plate 34 later. A plane mirror is provided on the surface of the buoyancy plate 34, and the light can be reflected to the laser rangefinder 57 through the reflection of the buoyancy plate 34. During this process, due to the overall movement of the auxiliary detection component 4 and the position detection component 5, the lead wire of the wire dispenser 31 also moves outside the load-bearing roller 41, and the load-bearing roller 41 is forced to rotate under the action of friction. The load-bearing roller 41 drives the extension column 42 to rotate and connect inside the fixed shaft hole 43. Under the action of the gravity of the counterweight cone 33, the counterweight cone 33 remains vertical. After the counterweight cone 33 is stationary, the lead wire of the wire dispenser 31 is released by the wire dispenser 31, causing the counterweight cone 33 to move into the water;

[0045] When measuring the height of the water level in a deep foundation pit of a project, during the process of the wire dispenser 31 paying out the wire for the counterweight cone 33, the wire of the wire dispenser 31 is pulled by the counterweight cone 33, so that the wire of the wire dispenser 31 squeezes the load-bearing roller 41. The load-bearing roller 41 drives the extension column 42 to squeeze the movable plate 46. The bottom end of the movable plate 46 is in contact with the top end of the stop column 55. The stop column 55 controls the position of the downward movement of the movable plate 46. When the counterweight cone 33 is at the bottom of the water, at this time the counterweight cone 33 will contact the ground. After the counterweight cone 33 contacts the ground, at this time the pulling force of the counterweight cone 33 on the wire dispenser 31 is weakened. At this time, under the action of the elastic force of the spring 45, the movable plate 46 is pushed upward. The movable plate 46 slides inside the vertical groove 54 through the limit rail 44. When the top end of the movable plate 46 squeezes the pressure sensor 52, at this time the integrated controller 15 receives the feedback and timely controls the wire dispenser 31 to stop paying out the wire through the integrated controller 15. The integrated controller 15 detects the wire-paying-out duration of the wire dispenser 31 to judge the wire-paying-out length of the wire dispenser 31. At the same time, when the wire dispenser 31 pays out the wire, the buoyancy plate 34 will move downward. When the buoyancy plate 34 contacts the water surface, at this time the buoyancy plate 34 will not move. The moving distance of the buoyancy plate 34 is detected by the laser rangefinder 57. When the buoyancy plate 34 no longer moves, this is the height of the water surface. Since the roller 35 is in contact with the wire of the wire dispenser 31, the friction during the movement of the buoyancy plate 34 can be reduced through the roller 35. Before the buoyancy plate 34 contacts the water surface, the bottom end of the buoyancy plate 34 is in contact with the top end of the counterweight cone 33. After the height of the buoyancy plate 34 is determined, the depth of the water is calculated by the duration of the subsequent downward movement of the counterweight cone 33 to contact the ground, so as to complete the measurement of the water level;

[0046] Based on the above principle, when the device measures the height of the water level in a deep foundation pit of a project, the measurement point can be adjusted, thereby increasing the measurement range. At the same time, such a measurement method does not require the staff to install the device into the water, which not only improves the measurement convenience but also ensures the safety of the staff.

[0047] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A water level monitoring device for a deep foundation pit, comprising a movement control component (1) and a position adjustment component (2), characterized in that: The front end of the movement control component (1) is fixedly connected to a launching control component (3), the lower end of the position adjustment component (2) is installed with a position detection component (5), and the inner side of the position detection component (5) is installed with an auxiliary detection component (4); The auxiliary detection component (4) comprises a load-bearing roller (41), and the left and right sides of the load-bearing roller (41) are fixedly connected to extension columns (42), the outer side of the extension column (42) is rotatably connected to the inner side of the fixed shaft hole (43) through a bearing, and the fixed shaft hole (43) is provided on the inner side of the movable plate (46), the front end and the rear end of the movable plate (46) are fixedly connected to the limit rail (44), and the bottom end of the movable plate (46) is fixedly connected to a spring (45); The position detection assembly (5) comprises a top plate (51), the bottom end of the top plate (51) is fixedly connected to a pressure sensor (52) and a frame (53), a vertical groove (54) is provided on the inner side of the frame (53), a blocking column (55) is fixedly connected to the inner side of the frame (53) near the lower end, a weight block (56) is fixedly connected to the bottom end of the frame (53), and a laser rangefinder (57) is fixedly connected to the bottom end of the weight block (56); The limiting rail (44) is slidably connected to the inner side of the vertical groove (54), and the bottom end of the spring (45) is fixedly connected to the inner side of the frame (53).

2. The deep foundation pit water level monitoring device according to claim 1 is characterized by: The mobile control assembly (1) comprises a counterweight (11), the bottom end of the counterweight (11) is fixedly connected to a moving vehicle (12), the front end of the moving vehicle (12) is provided with a placement groove (13), the inner side of the placement groove (13) is fixedly connected to a guide column (14), the right side of the counterweight (11) is fixedly connected to an integrated controller (15), and the integrated controller (15), the pressure sensor (52) and the laser rangefinder (57) are electrically connected.

3. The deep foundation pit water level monitoring device according to claim 1 is characterized in that: The position adjustment assembly (2) comprises an electric telescopic rod (21), the top end of the electric telescopic rod (21) being fixedly connected to a U-shaped plate (22), the bottom end of the electric telescopic rod (21) being fixedly connected to the lower end of a guide column (14), a sliding hole being provided on the inner side of the U-shaped plate (22), the inner side of the sliding hole of the U-shaped plate (22) being slidably connected to the outer side of the guide column (14), and the U-shaped plate (22) being electrically connected to an integrated controller (15).

4. The deep foundation pit water level monitoring device according to claim 3 is characterized by: The U-shaped plate (22) is rotatably connected to a first rotating arm (23) on the inner side, the first rotating arm (23) is rotatably connected to a fixing plate (24) on the lower end, the fixing plate (24) is fixedly connected to shaft columns (26) on both the left and right sides, the shaft column (26) is rotatably connected to a second rotating arm (25) on the outer side, the second rotating arm (25) is rotatably connected to the shaft column (26) at the front and rear ends, and one side of the shaft column (26) at the rear end is fixedly connected to the inner side of the placement groove (13).

5. The device for monitoring the water level of a deep foundation pit according to claim 4, characterized in that: A spherical groove is formed at the lower end of the fixing plate (24), the inner side of the spherical groove of the fixing plate (24) is fitted with the outer side of the ball block (27), the lower end of the ball block (27) is fixedly connected to a vertical rod (28), the top and bottom ends of the vertical rod (28) are fixedly connected to the ball block (27), and the outer side of the ball block (27) at the lower end is fitted with the inner side of the spherical groove formed on the top plate (51).

6. The water level monitoring device for a deep foundation pit according to claim 1 is characterized by: The launching control assembly (3) comprises a wire releaser (31), the rear end of the wire releaser (31) is fixedly connected to the front end of the mobile vehicle (12), the bottom end of the lead wire of the wire releaser (31) is fixedly connected to a counterweight cone block (33), the lead wire of the wire releaser (31) passes through the inner side of a threading hole (36), the outer side of the lead wire of the wire releaser (31) is in contact with the outer side of a roller (35), the roller (35) is rotatably connected to the inner side of an ear seat (32), the ear seat (32) is fixedly connected to the inner side of the threading hole (36), and the threading hole (36) is provided on the inner side of the buoyancy plate (34).

7. The device for monitoring the water level of a deep foundation pit according to claim 1, characterized in that: The outer side of the load-bearing roller (41) near the upper end is in contact with the lead wire of the wire unwinder (31), the bottom end of the movable plate (46) is in contact with the top end of the blocking column (55), and a distance is provided between the top end of the movable plate (46) and the bottom end of the pressure sensor (52).

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