Land area measuring device

Abstract

The utility model discloses a land area measuring device which comprises a point collecting rod, one side of the point collecting rod is provided with a mounting frame, the mounting frame is provided with a collector, one side of the mounting frame is provided with an adjusting device, the adjusting device comprises a fixed sleeve, a control panel, a switching sleeve, a control sleeve, a control groove, a switching groove, a switching block, a control block and a movable block, the control panel is connected to one side of the control sleeve, and the movable block is connected to the other side of the control sleeve. The control groove is formed in the outer side of the switching sleeve, the switching groove is formed in the inner side of the switching sleeve, the control block is arranged on the inner side of the control plate along a spiral line, the movable block is installed on one side of the switching block, and the locking mechanism is installed on the outer side of the fixed sleeve and comprises a shifting sleeve, a rotating plate, a round hole, an arc-shaped groove, a shifting block, a shifting spring, an ejector rod, an ejector plate and a fixed block. The circular hole is formed in one end of the arc-shaped groove, the shifting spring is connected with the two adjacent shifting blocks, the top plate is installed on the ejector rod, and the fixing blocks are installed on the outer side of the fixing sleeve. The height of the collector is flexibly adjusted, and the structural stability in the using process is guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of land area measurement technology, and more specifically, to a land area measurement device. Background Technology

[0002] In existing land area measurement devices, the data logger and the sampling rod are usually connected in a fixed manner. This design has obvious limitations. The data logger is rigidly connected to the sampling rod by welding or bolting, making it impossible to adjust the relative position between the two. In actual use, due to the large differences in the height of operators, this fixed structure makes the equipment unsuitable for users of different heights. For example, taller surveyors need to bend over to read the data, while shorter people have to stand on tiptoe to read the data. Long-term operation can easily cause personnel fatigue, affecting measurement efficiency and accuracy. In addition, in complex terrain environments, such as sloping areas, the fixed height of the data logger is often difficult to adjust to avoid obstacles and makes it inconvenient for personnel to read the data, resulting in measurement data deviations or even acquisition failures.

[0003] Some improved devices attempt to achieve height adjustment of the data logger through a simple structure, but these designs have revealed significant stability issues in practical applications. When working in the field, they are easily affected by vibration, wind, or accidental collisions, causing the data logger's position to shift. Especially when moving and measuring on uneven ground, even slight shaking of the equipment can cause the originally adjusted height to change, seriously affecting work efficiency and reducing the reliability and lifespan of the equipment. Utility Model Content

[0004] (a) Technical problems to be solved

[0005] In view of the problems existing in the prior art, this utility model provides a land area measuring device to solve the technical problems mentioned in the background art.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, this utility model provides the following technical solution: a land area measuring device, including a sampling rod, a mounting frame detachably mounted on one side of the sampling rod, a data collector detachably mounted on the mounting frame, and an adjustment device mounted on one side of the mounting frame. The adjustment device includes a fixed sleeve, a control plate, a switching sleeve, a control slot, a switching slot, a switching block, a control block, and a movable block. The fixed sleeve is movably disposed on the outside of the sampling rod and fixedly mounted on one side of the mounting frame. The control plate is fixedly connected to one side of the control sleeve. The switching sleeve is slidably disposed on the outside of the fixed sleeve and rotatably mounted on the outside of the fixed sleeve. The control slot is spirally formed on the outside of the switching sleeve, and the switching slot is inclinedly formed on the inside of the switching sleeve. The switching block is slidably mounted on the outside of the fixed sleeve. Installed in the switching slot, multiple control blocks are arranged along a spiral line on the inner side of the control plate. The control blocks slide in the control slot. The movable block is fixedly installed on one side of the switching block. A locking mechanism is installed on the outside of the fixed sleeve. The locking mechanism includes a shift sleeve, a rotating plate, a round hole, an arc groove, a shift block, a shift spring, a top rod, a top plate, and a fixed block. The shift sleeve is slidably fitted on the outside of the fixed sleeve. The rotating plate is rotatably installed on the outside of the fixed sleeve. The round hole is opened at one end of the arc groove. The arc groove is opened on the rotating plate. The shift block is movably disposed on one side of the control sleeve. The two ends of the shift spring are respectively connected to two adjacent shift blocks. The top rod is fixedly installed on one side of the shift sleeve. Two top plates are fixedly installed on the top rod. Multiple fixed blocks are fixedly installed on the outside of the fixed sleeve.

[0008] The present invention is further configured such that a top spring is connected to one side of the displacement sleeve, the top spring is movably sleeved on the outside of the top rod, and the other end of the top spring abuts against one side of the rotating plate.

[0009] The present invention is further configured such that a plurality of shifting rails are connected to one side of the control sleeve, and a plurality of shifting grooves are opened on one side of the shifting block. The shifting rails are adapted to the shifting grooves, and the precise cooperation between the shifting rails and the shifting grooves realizes reliable transmission between the control sleeve and the shifting block.

[0010] The present invention is further configured such that a shifting wheel is rotatably provided on one side of the shifting block, and the shifting wheel is engaged between two fixed blocks. The rolling design of the shifting wheel greatly reduces frictional resistance, enabling it to move smoothly between the fixed blocks, while ensuring positioning accuracy when locking.

[0011] The present invention is further configured such that a plurality of movable springs are connected to one side of the movable block, and a movable plate is connected to the other end of the movable springs.

[0012] The present invention is further configured such that a plurality of anti-slip strips are fixedly provided on one side of the movable plate, and the anti-slip strips provided on the inner side of the movable plate can generate sufficient frictional force when pressed to prevent relative sliding between the sampling rod and the mounting frame.

[0013] The present invention is further configured such that both the displacement block and the displacement groove are designed with a T-shaped structure. The T-shaped structure enhances the fit strength between the displacement block and the displacement groove, preventing deformation or separation under stress.

[0014] The present invention is further provided in that multiple rubber strips are fixedly provided on the outer sides of the rotating plate, the shifting sleeve and the control sleeve. The rubber strips not only improve the operating feel, but also play a role in preventing slippage.

[0015] (III) Beneficial Effects

[0016] Compared with the prior art, the present invention provides a land area measuring device, which has the following beneficial effects:

[0017] 1. The adjustment device, through the linkage design of the control sleeve and the switching sleeve, utilizes the cooperation of the spiral control groove and the inclined switching groove to achieve precise adjustment of the collector height. When the control sleeve is rotated, the control plate drives the control block to slide along the control groove, causing the switching sleeve to generate axial displacement. This displacement, in turn, drives the movable block to move through the switching block, ultimately releasing the fixation and realizing the adjustment function. This spiral transmission structure not only ensures a smooth and reliable adjustment process but also ensures close contact between the movable plate and the sampling rod by pressing the movable spring. This effectively solves the problem that traditional fixed structures cannot adapt to operators of different heights. At the same time, the inclined switching groove design makes height adjustment more effortless; the operator only needs to turn the control sleeve lightly to complete the adjustment, greatly improving the efficiency of field operations.

[0018] 2. The locking mechanism employs a multi-layered safety design to ensure stability after the height is fixed. Through the linkage between the rotating plate and the shifting sleeve, the first layer of locking is formed by the limiting effect of the arc groove and the top rod. When the shifting sleeve resets, its inner wall forms a radial constraint on the shifting wheel, preventing the control sleeve from rotating accidentally, thus forming the second layer of locking. The elastic reset function of the shifting spring ensures that the shifting block always has a tendency to retract inward, ensuring that the shifting wheel can accurately engage between the fixed blocks, forming the third layer of mechanical locking. This triple locking mechanism effectively overcomes the defects of traditional adjustable structures that are easily affected by vibration. Even in rugged terrain or strong wind conditions, it can maintain the stable positioning of the data collector. The overall structure, through the synergistic effect of mechanical linkage and elastic elements, achieves fixed stability while ensuring adjustment flexibility, significantly improving the accuracy of measurement data and the service life of the equipment. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of a land area measuring device according to the present invention;

[0020] Figure 2 This is a schematic diagram of the collector and mounting bracket in this utility model;

[0021] Figure 3This is a schematic diagram of the dispersed structure of the adjusting device and locking mechanism in this utility model;

[0022] Figure 4 This is a schematic cross-sectional view of the adjusting device and locking mechanism in this utility model.

[0023] Figure 5 This is a cross-sectional view of the adjusting device and locking mechanism in this utility model.

[0024] In the diagram: 1. Sampling rod; 2. Mounting frame; 3. Data collector; 4. Fixing sleeve; 5. Control board; 6. Switching sleeve; 7. Control sleeve; 8. Control groove; 9. Switching groove; 10. Switching block; 11. Control block; 12. Movable block; 13. Shifting sleeve; 14. Rotating plate; 15. Round hole; 16. Arc groove; 17. Shifting block; 18. Shifting spring; 19. Top rod; 20. Top plate; 21. Fixing block; 22. Top spring; 23. Shifting rail; 24. Shifting groove; 25. Shifting wheel; 26. Movable spring; 27. Movable plate; 28. Anti-slip strip; 29. ​​Rubber strip. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0027] In this utility model, unless otherwise stated, the orientations used, such as "up" and "down", usually refer to the direction shown in the accompanying drawings, or to the vertical, perpendicular, or gravitational direction; similarly, for ease of understanding and description, "left" and "right" usually refer to the left and right shown in the accompanying drawings; "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not used to limit this utility model.

[0028] Please see Figures 1-5A land area measuring device includes a sampling rod 1, a mounting frame 2 detachably mounted on one side of the sampling rod 1, a data collector 3 detachably mounted on the mounting frame 2, and an adjustment device mounted on one side of the mounting frame 2. The adjustment device includes a fixed sleeve 4, a control plate 5, a switching sleeve 6, a control sleeve 7, a control groove 8, a switching groove 9, a switching block 10, a control block 11, and a movable block 12. The fixed sleeve 4 is movably disposed on the outside of the sampling rod 1 and fixedly mounted on one side of the mounting frame 2. The control plate 5 is fixedly connected to one side of the control sleeve 7. The switching sleeve 6 is slidably disposed on the outside of the fixed sleeve 4, and the control sleeve 7 is rotatably mounted on the outside of the fixed sleeve 4. The control groove 8 is spirally opened on the outside of the switching sleeve 6, the switching groove 9 is inclinedly opened on the inside of the switching sleeve 6, the switching block 10 is slidably mounted in the switching groove 9, and multiple control blocks 11 are arranged along a spiral line on the control plate 12. Inside the control plate 5, the control block 11 slides in the control groove 8, the movable block 12 is fixedly installed on one side of the switching block 10, and a locking mechanism is installed on the outside of the fixed sleeve 4. The locking mechanism includes a shift sleeve 13, a rotating plate 14, a round hole 15, an arc groove 16, a shift block 17, a shift spring 18, a top rod 19, a top plate 20, and a fixed block 21. The shift sleeve 13 is slidably sleeved on the outside of the fixed sleeve 4, the rotating plate 14 is rotatably installed on the outside of the fixed sleeve 4, the round hole 15 is opened at one end of the arc groove 16, the arc groove 16 is opened on the rotating plate 14, the shift block 17 is movably set on one side of the control sleeve 7, the two ends of the shift spring 18 are respectively connected to two adjacent shift blocks 17, the top rod 19 is fixedly installed on one side of the shift sleeve 13, two top plates 20 are fixedly installed on the top rod 19, and multiple fixed blocks 21 are fixedly installed on the outside of the fixed sleeve 4.

[0029] In this embodiment, when it is necessary to adjust the height of the collector 3 on the sampling rod 1, the rotating plate 14 is first rotated forward, causing the rotating plate 14 to drive the circular hole 15 and the arc-shaped groove 16 to rotate. When the circular hole 15 rotates to a position concentric with the top plate 20, the shifting sleeve 13 is pushed. The shifting sleeve 13 drives the top rod 19 and the top plate 20 to slide through the circular hole 15, and the shifting sleeve 13 will cooperate with the rotating plate 14 to compress the top spring 22. When the top spring 22 is compressed to its limit, a part of the top plate 20 near the shifting sleeve 13 just passes through the circular hole 15. It moves to the other side of the rotating plate 14, and then rotates the rotating plate 14 in the opposite direction, causing the rotating plate 14 to drive the circular hole 15 and the arc groove 16 to rotate in the opposite direction, so that the push rod 19 enters the arc groove 16. At this time, the push rod 19 cooperates with the top plate 20 near the shift sleeve 13 to limit the shift sleeve 13 to one side of the rotating plate 14, so that the shift sleeve 13 no longer limits the outside of the shift wheel 25. Then, the control sleeve 7 is rotated in the forward direction, so that the control sleeve 7 drives the shift rail 23 to rotate in the forward direction. Then, the shift rail 23 cooperates with the shift groove 24 to drive the shift. When block 17 rotates forward, the shifting block 17 will cause the shifting wheel 25 to roll out between the two fixed blocks 21. The shifting wheel 25 will also cause the shifting block 17 to slide outward along the shifting rail 23 and the shifting groove 24, causing the shifting block 17 to stretch the shifting spring 18 outward. At the same time, the control sleeve 7 will drive multiple control blocks 11 to rotate forward through the control plate 5, causing the control blocks 11 to slide forward along the control groove 8. Then, the switching sleeve 6 will cause the inner inclined opening in the switching groove 9 to slide forward, and then the switching block 10 will... The movable block 12 moves outward, increasing the distance between the movable block 12 and the movable plate 27. Then the movable spring 26 resets. After the movable spring 26 is fully reset, the movable block 12 pulls the movable plate 27 outward through the movable spring 26, so that the inner wall of the movable plate 27 no longer clamps the outer side of the sampling rod 1. Then the position of the collector 3 can be moved, so that the collector 3 drives the fixed sleeve 4 to slide along the outer wall of the sampling rod 1 through the mounting bracket 2. When the collector 3 moves to a suitable height, the movement of the collector 3 stops.

[0030] Please see Figures 2-5 As a further implementation of the overall equipment: a top spring 22 is connected to one side of the shift sleeve 13, the top spring 22 is movably sleeved on the outside of the top rod 19, and the other end of the top spring 22 abuts against one side of the rotating plate 14.

[0031] Multiple shift rails 23 are connected to one side of the control sleeve 7, and multiple shift grooves 24 are opened on one side of the shift block 17. The shift rails 23 and the shift grooves 24 are adapted to each other.

[0032] A shifting wheel 25 is provided on one side of the shifting block 17, and the shifting wheel 25 is engaged between two fixed blocks 21.

[0033] Multiple movable springs 26 are connected to one side of the movable block 12, and a movable plate 27 is connected to the other end of the movable spring 26.

[0034] Multiple anti-slip strips 28 are fixedly installed on one side of the movable board 27.

[0035] Both the shift block 17 and the shift slot 24 are designed with a T-shaped structure.

[0036] Multiple rubber strips 29 are fixedly provided on the outer sides of the rotating plate 14, the shifting sleeve 13 and the control sleeve 7.

[0037] More specifically, after the collector 3 is moved to a suitable height, the control sleeve 7 is rotated in the reverse direction. The control sleeve 7, through the shift rail 23 on one side and the shift groove 24, drives the shift block 17 and the shift wheel 25 to rotate in the reverse direction. The control sleeve 7, through the control plate 5, drives the control block 11 to slide in the reverse direction along the control groove 8. Then, the switching sleeve 6 drives the inner switching groove 9 to slide in the reverse direction. Then, the switching block 10 drives the movable block 12 to slide inward and reset. Then, the movable block 12, through the movable spring 26, drives the movable plate 27 to move inward. After the inner wall of the moving plate 27 contacts the outer wall of the sampling rod 1, the moving block 12 continues to move. Then, the moving block 12 and the moving plate 27 work together to press the moving spring 26, causing the moving spring 26 to be compressed. Then, the moving plate 27 clamps the outer wall of the sampling rod 1 through the multiple anti-slip strips 28 set on the inner wall. At this time, the shifting rail 23 and the shifting groove 24 work together to drive the shifting block 17 to move between the two original fixed blocks 21. Then, the shifting spring 18 resets and pulls the shifting block 17 to slide inward along the shifting rail 23 and the shifting groove 24, thus shifting the position. Block 17 drives the shifting wheel 25 to engage between the two fixed blocks 21, and then rotates the rotating plate 14 forward again, causing the rotating plate 14 to drive the circular hole 15 and the arc-shaped groove 16 to rotate forward. When the circular hole 15 rotates to the position corresponding to the top plate 20, the top spring 22 pushes the shifting sleeve 13 to slide back to its original position. Then, the shifting sleeve 13 drives the two top plates 20 to slide back to their original position through the top rod 19. When the top spring 22 is fully reset, the top plate 20 set at the top of the top rod 19 moves back to the original side of the rotating plate 14, and then rotates the plate 14 again. Plate 14 causes the rotating plate 14 to rotate and reset the circular hole 15 and the arc groove 16 to a position that does not correspond to the top plate 20. Then, the top rod 19, together with the top plate 20, limits and supports the shift sleeve 13 to one side of the rotating plate 14, so that the shift sleeve 13 cannot slide easily. Then, the inner wall of the shift sleeve 13 limits the outer wall of the shift wheel 25, so that the shift wheel 25 and the shift block 17 cannot slide outward, thereby realizing the rotation limit of the control sleeve 7, preventing accidental movement, and thus ensuring the stable fixation of the height of the collector 3.

[0038] In summary, during the use or operation of the overall equipment: when it is necessary to adjust the height of the collector 3 on the sampling rod 1, first rotate the rotating plate 14 in the forward direction, so that the rotating plate 14 drives the circular hole 15 and the arc groove 16 to rotate. When the circular hole 15 rotates to a position concentric with the top plate 20, it pushes the shifting sleeve 13. The shifting sleeve 13 drives the top rod 19 and the top plate 20 to slide through the circular hole 15, and the shifting sleeve 13 will cooperate with the rotating plate 14 to compress the top spring 22. When the top spring 22 is compressed to its limit, a part of the top plate 20 near the shifting sleeve 13 just... It passes through the circular hole 15 and moves to the other side of the rotating plate 14. Then, the rotating plate 14 is rotated in the opposite direction, causing the circular hole 15 and the arc groove 16 to rotate in the opposite direction, so that the push rod 19 enters the arc groove 16. At this time, the push rod 19 cooperates with the top plate 20 near the shift sleeve 13 to limit the shift sleeve 13 to one side of the rotating plate 14, so that the shift sleeve 13 no longer limits the outside of the shift wheel 25. Then, the control sleeve 7 is rotated in the forward direction, so that the control sleeve 7 drives the shift rail 23 to rotate in the forward direction. Then, the shift rail 23 cooperates with the shift groove 2. 4. The shift block 17 rotates forward, causing the shift wheel 25 to roll out from between the two fixed blocks 21. The shift wheel 25 then causes the shift block 17 to slide outward along the shift rail 23 and the shift groove 24, stretching the shift spring 18 outward. Simultaneously, the control sleeve 7 rotates forward via the control plate 5, causing the control blocks 11 to slide forward along the control groove 8. Then, the switching sleeve 6, with its inner inclined opening in the switching groove 9, slides forward, and the switching block 1... 0 will cause the movable block 12 to move outward, thus increasing the distance between the movable block 12 and the movable plate 27. Then the movable spring 26 will reset. After the movable spring 26 is fully reset, the movable block 12 will pull the movable plate 27 outward through the movable spring 26, so that the inner wall of the movable plate 27 will no longer clamp the outer side of the sampling rod 1. Then the position of the collector 3 can be moved, so that the collector 3 will slide along the outer wall of the sampling rod 1 through the mounting bracket 2 and the fixing sleeve 4. When the collector 3 moves to a suitable height, the movement of the collector 3 will stop.

[0039] After the collector 3 is moved to a suitable height, the control sleeve 7 is rotated in the reverse direction. The control sleeve 7, through the shift rail 23 on one side and the shift groove 24, drives the shift block 17 and the shift wheel 25 to rotate in the reverse direction. The control sleeve 7, through the control plate 5, drives the control block 11 to slide in the reverse direction along the control groove 8. Then, the switching sleeve 6 drives the inner switching groove 9 to slide in the reverse direction. Then, the switching block 10 drives the movable block 12 to slide inward and reset. Then, the movable block 12, through the movable spring 26, drives the movable plate 27 to move inward. When the movable plate 27 moves inward... After the inner wall of the sampling rod 1 contacts the outer wall, the movable block 12 continues to move. Then, the movable block 12 and the movable plate 27 cooperate to press the movable spring 26, so that the movable spring 26 is compressed. Then, the movable plate 27 clamps the outer wall of the sampling rod 1 through the multiple anti-slip strips 28 set on the inner wall. At this time, the shifting rail 23 and the shifting groove 24 cooperate to drive the shifting block 17 to move between the two fixed blocks 21. Then, the shifting spring 18 resets and pulls the shifting block 17 to slide inward along the shifting rail 23 and the shifting groove 24, so that the shifting block 17... 7. The shifting wheel 25 is engaged between the two fixed blocks 21. Then, the rotating plate 14 is rotated forward again, causing the circular hole 15 and the arc groove 16 to rotate forward. When the circular hole 15 rotates to the position corresponding to the top plate 20, the top spring 22 pushes the shifting sleeve 13 to slide back to its original position. Then, the shifting sleeve 13 drives the two top plates 20 to slide back to their original position through the top rod 19. When the top spring 22 is fully reset, the top plate 20 at the top of the top rod 19 moves back to the original side of the rotating plate 14. Then, the rotating plate is rotated again. 14. This causes the rotating plate 14 to rotate and reset the circular hole 15 and the arc groove 16 to a position that does not correspond to the top plate 20. Then, the top rod 19, in conjunction with the top plate 20, limits and supports the shift sleeve 13 to one side of the rotating plate 14, making it impossible for the shift sleeve 13 to slide easily. Then, the inner wall of the shift sleeve 13 limits the outer wall of the shift wheel 25, making it impossible for the shift wheel 25 and the shift block 17 to slide outward. This achieves rotational limitation of the control sleeve 7, preventing accidental movement and ensuring stable fixation of the height of the collector 3.

[0040] Of all the solutions mentioned above, those involving the connection between two components can be selected according to the actual situation, such as welding, bolt and nut connection, bolt or screw connection, or other known connection methods, which will not be elaborated here. For all the fixed connections mentioned above, welding is preferred. Although embodiments of this utility model have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this utility model. The scope of this utility model is defined by the appended claims and their equivalents.

Claims

1. A land area measuring device, comprising a sampling rod (1), a mounting frame (2) on one side of the sampling rod (1), and a data collector (3) mounted on the mounting frame (2), characterized in that: An adjustment device is installed on one side of the mounting bracket (2). The adjustment device includes a fixed sleeve (4), a control plate (5), a switching sleeve (6), a control sleeve (7), a control groove (8), a switching groove (9), a switching block (10), a control block (11), and a movable block (12). The control plate (5) is connected to one side of the control sleeve (7). The control groove (8) is spirally opened on the outside of the switching sleeve (6). The switching groove (9) is inclinedly opened on the inside of the switching sleeve (6). Multiple control blocks (11) are arranged along a spiral line on the inside of the control plate (5). The movable block (12) is installed on one side of the switching block (10). The fixed sleeve (4) is on the outside of the control plate (5). A locking mechanism is installed on the side, which includes a shift sleeve (13), a rotating plate (14), a round hole (15), an arc groove (16), a shift block (17), a shift spring (18), a top rod (19), a top plate (20), and a fixing block (21). The round hole (15) is opened at one end of the arc groove (16), the arc groove (16) is opened on the rotating plate (14), the shift spring (18) is connected to two adjacent shift blocks (17), the top rod (19) is installed on one side of the shift sleeve (13), two top plates (20) are installed on the top rod (19), and multiple fixing blocks (21) are installed on the outside of the fixing sleeve (4).

2. The land area measuring device according to claim 1, characterized in that: The shift sleeve (13) is connected to a top spring (22) on one side. The top spring (22) is movably sleeved on the outside of the top rod (19), and the other end of the top spring (22) abuts against one side of the rotating plate (14).

3. The land area measuring device according to claim 2, characterized in that: The control sleeve (7) is connected to a plurality of shift rails (23) on one side, and the shift block (17) is provided with a plurality of shift grooves (24) on one side, and the shift rails (23) and shift grooves (24) are adapted to each other.

4. A land area measuring device according to claim 3, characterized in that: The shifting block (17) has a shifting wheel (25) on one side that rotates, and the shifting wheel (25) is engaged between two fixed blocks (21).

5. A land area measuring device according to any one of claims 1-4, characterized in that: The movable block (12) is connected to a plurality of movable springs (26) on one side, and a movable plate (27) is connected to the other end of the movable springs (26).

6. A land area measuring device according to claim 5, characterized in that: Multiple anti-slip strips (28) are fixedly provided on one side of the movable plate (27).

7. A land area measuring device according to claim 4, characterized in that: Both the shift block (17) and the shift groove (24) are T-shaped structures.

8. A land area measuring device according to claim 1, characterized in that: Multiple rubber strips (29) are fixedly provided on the outer sides of the rotating plate (14), the shifting sleeve (13) and the control sleeve (7).

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