Measuring device for power construction

By improving the adaptive stabilizing tripod, the stability problem of traditional measuring instruments on complex terrain has been solved, realizing stable support and accurate measurement of measuring instruments in power construction, thus improving construction efficiency and safety.

CN224135614UActive Publication Date: 2026-04-17HENAN SHANXIN POWER ENG CO LTD
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
HENAN SHANXIN POWER ENG CO LTD
Filing Date
2025-06-10
Publication Date
2026-04-17

AI Technical Summary

Technical Problem

Traditional power engineering surveying instruments are prone to slippage or settlement on slopes or sloping ground, leading to decreased measurement accuracy and equipment damage, which affects construction efficiency and safety.

Method used

The adaptive stabilizing tripod uses a leg tube structure consisting of connecting tubes and support tubes, combined with telescopic rods, elastic elements, and positioning bolts to achieve stable support for the tripod on complex terrain, and adjust the support angle and height.

Benefits of technology

It improves the stability and measurement accuracy of surveying instruments in complex terrain, reduces the risk of equipment damage, and enhances construction efficiency and safety.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model relates to the technical field of measuring equipment, in particular to a measuring device for power construction. Comprising a tripod and a measuring instrument, the tripod comprises a base for loading the measuring instrument and three foot tubes rotatably installed on the periphery of the base through a damping rotating shaft, at least one foot tube is divided into a supporting tube and a connecting tube embedded in the supporting tube, a positioning bolt is arranged between the connecting tube and the supporting tube, and two sets of telescopic rods are installed at the end of the connecting tube in a spaced, radial and sliding mode. Elastic pieces are arranged between the telescopic rods and the connecting pipes, and connecting holes in one-to-one correspondence with the telescopic rods are formed in the upper ends of the supporting pipes. By adjusting the connecting state of the connecting pipes and the supporting pipes, truss supporting can be formed in the stretching state, the supporting angle of the lower side foot pipes is adjusted, the supporting range is widened, and therefore the tripod can be supported on the inclined face more stably.
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Description

Technical Field

[0001] This utility model relates to the field of measuring equipment technology, and in particular to a measuring device for power construction. Background Technology

[0002] Power engineering is a technical field centered on the production, transmission, and distribution of electrical energy, encompassing the planning, construction, and operation and maintenance of facilities such as power plants, transmission and distribution lines, and substations. In power engineering construction, surveying technology is a core element ensuring project accuracy. It requires precise measurement of parameters such as equipment installation locations, line routes, and tower verticality to ensure the stability of the power grid structure and operational safety. For example, deviations in the tilt angle of transmission towers can lead to conductor tension imbalances, and misalignments in the coordinates of substation equipment can cause potential hazards such as insufficient insulation distance.

[0003] Traditional power engineering surveying primarily relies on high-precision optical instruments such as total stations and theodolites. However, the measurement accuracy of these instruments is highly dependent on the stability of the support structure. Their standard tripod uses an equal-length hinged leg structure, unfolding into a lateral triangular support structure to ensure stable support for the total station. However, when working on sloping ground such as hillsides or riverbanks, the entire equipment tilts, and the drooping part slips or settles under gravity, causing the instrument platform to tilt slightly. This forces repeated leveling during the measurement process, severely impacting work efficiency. More seriously, support instability can cause damage to precision instruments worth tens of thousands of yuan from falls, or trigger measurement data drift, leading to accumulated construction errors.

[0004] Therefore, developing an adaptive and stable tripod that can adapt to complex terrain has become a key technical requirement for improving the reliability of power engineering measurements. Utility Model Content

[0005] The purpose of this utility model is to solve the problems existing in the prior art by proposing a measuring device for power construction.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A measuring device for power construction includes a tripod and a measuring instrument. The tripod includes a base for mounting the measuring instrument, and three legs rotatably mounted around the base via a damping shaft. At least one leg is divided into a support tube and a connecting tube embedded in the support tube. A positioning bolt is provided between the connecting tube and the support tube. Two sets of telescopic rods are radially slidably installed at a distance from the end of the connecting tube. An elastic element is provided between the telescopic rods and the connecting tube. The upper end of the support tube is provided with connecting holes corresponding to the telescopic rods.

[0008] Preferably, the connecting pipe is a reducing pipe, and the outer wall of the part of the connecting pipe inserted into the support pipe is in contact with the inner wall of the support pipe.

[0009] Preferably, the upper end of the support tube is symmetrically provided with an upwardly extending support, the outer wall of the support is an arc shape that matches the inner wall of the support tube, and two sets of connecting holes are provided on the support.

[0010] Preferably, the outer wall of the support tube is provided with a threaded hole, and the part of the connecting tube inserted into the support tube is provided with a limiting hole corresponding to the threaded hole, and the positioning bolt is screwed into the threaded hole and passes through the limiting hole.

[0011] Preferably, the foot tube is fitted with an extension foot, the extension foot is provided with a buckle frame, and a locking bolt that abuts against the outer wall of the foot tube is screwed onto the buckle frame.

[0012] Preferably, both sides of the extended support leg are provided with C-shaped grooves, each groove is fitted with a leg tube, the upper ends of the two leg tubes on the same extended support leg are connected to a connecting seat, and the lower ends are connected to a cable tray. The connecting seat is rotatably connected to the base via a damping shaft, and the cable tray is provided with C-shaped buckles that cover the two leg tubes.

[0013] Preferably, the buckle frame is a straight groove frame, and the straight groove in the straight groove frame buckles the two leg tubes and the extension leg together.

[0014] Preferably, the contact surface between the extended leg and the leg tube is provided with friction damping.

[0015] Preferably, the outer diameter of the exposed part of the connecting pipe is the same as the outer diameter of the support pipe, and the variable diameter end of the connecting pipe is provided with a groove that mates with the support.

[0016] Preferably, a claw seat is suspended and fixed on the lower end face of the base, a central shaft is rotatably mounted on the claw seat, a connecting ring is threaded on the central shaft, and a support rod corresponding to the foot tube is rotatably mounted on the outer edge of the connecting ring. The other end of the support rod is rotatably connected to the bottom side wall of the foot tube, and at least one support rod is divided into a screw cylinder and a stud.

[0017] Compared with the prior art, this utility model provides a measuring device for power construction, which has the following advantages:

[0018] 1. This utility model improves the tripod leg tube by dividing the leg tube into a connecting tube and a support tube. By adjusting the connection state of the connecting tube and the support tube, a truss support can be formed in the extended state. The support angle of the lower leg tube can be adjusted to extend the support range, thereby making the tripod more stable on the inclined plane.

[0019] 2. In this utility model, an extension leg is provided on the leg tube, and the height of the tripod is controlled by controlling the extension and retraction of the diffraction leg on the leg tube.

[0020] 3. This utility model also includes an auxiliary support structure for providing additional support to the three legs of the tripod, making the installation more stable.

[0021] Other advantages, objectives and features of this invention will be set forth in part in the description which follows; and in part will be apparent to those skilled in the art upon examination of the following description; or may be taught from practice of this invention. Attached Figure Description

[0022] Figure 1 This is a three-dimensional schematic diagram of the present invention.

[0023] Figure 2 This is a front view schematic diagram of the present invention.

[0024] Figure 3 This is a side view of the present invention.

[0025] Figure 4 This is a schematic diagram of the foot tube adjustment when the present invention is installed on a slope.

[0026] Figure 5 This is a partial schematic diagram of point A in Figure 3 of this utility model.

[0027] Figure 6 For the present utility model Figure 4 A partial schematic diagram of point B in the middle.

[0028] Figure 7 This is a cross-sectional view of the telescopic rod at the end of the connecting pipe of this utility model.

[0029] Figure 8 This is a schematic diagram of the connection between the connecting pipe and the support pipe of this utility model.

[0030] Figure 9 This is a schematic diagram of the cable tray 10 of this utility model.

[0031] Figure 10 This is a schematic diagram of the buckle frame 16 structure of this utility model.

[0032] Figure 11 This is a schematic diagram of the single leg tube and the extended support leg of this utility model.

[0033] Figure 12 This is a bottom view of the present invention.

[0034] In the diagram: 1. Tripod; 2. Measuring instrument; 3. Telescopic rod; 4. Connecting hole; 5. Support; 6. Slot; 7. Positioning bolt; 8. Limiting hole; 9. Connecting seat; 10. Cable tray; 11. Claw seat; 12. Central shaft; 13. Connecting ring; 14. Support rod; 15. Extension leg; 16. Frame buckle; 17. Ground cone; 18. Locking bolt; 101. Base; 102. Leg tube; 1021. Connecting tube; 1022. Support tube; 1401. Screw barrel; 1402. Stud. Detailed Implementation

[0035] The following will refer to the appendix in the embodiments of this utility model. Figure 1-12 The technical solutions in the embodiments of this utility model will be clearly and completely described. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments.

[0036] Example 1: To address the problems existing in the prior art, this example provides a measuring device for power construction, including a tripod 1 and a measuring instrument 2. The tripod 1 includes a base 101 for mounting the measuring instrument 2. Three foot tubes 102 are rotatably mounted around the base 101 via a damping shaft. At least one foot tube 102 is divided into a support tube 1022 and a connecting tube 1021 embedded in the support tube 1022. A positioning bolt 7 is provided between the connecting tube 1021 and the support tube 1022. Two sets of telescopic rods 3 are radially slidably installed at the end of the connecting tube 1021 at intervals. An elastic element is provided between the telescopic rods 3 and the connecting tube 1021. The upper end of the support tube 1022 is provided with connecting holes 4 corresponding to the telescopic rods 3.

[0037] Specifically, the measuring instrument 2 can be any measuring instrument such as a total station, theodolite, or laser instrument, and has a built-in leveling mechanism for adjusting the horizontal position. The base 101 has a through hole at its center, and a mounting bolt is inserted through the lower end of the through hole. The mounting bolt engages with the screw hole at the lower end of the base of the measuring instrument 2 to achieve fixed installation of the measuring instrument 2 on the base 101.

[0038] Tripod 1 includes a base 101 and multiple legs 102 rotatably mounted around the base 101. The legs 102 are rotatably connected to the base 101 via damping pivots. When the legs are locked in a damping manner, the friction between the pads is damped, thereby reducing the rotational flexibility of the legs 102 and preventing the legs 102 from rotating too freely, which would affect the stability of the tripod 1.

[0039] Based on the above structure, a tripod 1 can be constructed to support and install the measuring instrument 2.

[0040] In order to enable the measuring instrument 2 to be installed stably in more complex terrains, such as on a slope, it is necessary to set up an auxiliary support on the lower side of the slope to ensure the stable support of the tripod 1 and to adjust the horizontal position of the base 101 so that the measuring instrument 2 can be adjusted horizontally.

[0041] Therefore, in this solution, at least one (there can be one, two, or three; this solution uses one as an example) of the three sets of foot tubes 102 is improved: the foot tube 102 is divided into a connecting tube 1021 and a supporting tube 1022. The upper end of the connecting tube 1021 is rotatably connected to the base 101 via a damping pivot, serving as the connection basis with the base 101; the lower end of the connecting tube 1021 is inserted into the upper end of the supporting tube 1022.

[0042] The lower end of the connecting pipe 1021 has slots spaced apart on both sides, and a telescopic rod 3 is embedded in each slot. An elastic element, a spring, is provided between the telescopic rod 3 and the slot. When the lower end of the connecting pipe 1021 is inserted into the support pipe 1022, the end of the telescopic rod 3 abuts against the inner wall of the support pipe 1022 and retracts into the slot, compressing the spring. The upper end of the support pipe 1022 has connecting holes 4 on both sides, corresponding one-to-one with the telescopic rod 3. The two sets of connecting holes 4 are not arranged along the axial direction of the support pipe 1022. The protruding end of the telescopic rod 3 is circular, facilitating insertion and retraction through the connecting holes 4.

[0043] To prevent the connecting pipe 1021 from moving or separating from the support pipe 1022 under non-active conditions, a threaded hole is provided on the outer wall of the support pipe 1022, and a limiting hole 8 is provided at the insertion point of the connecting pipe 1021 into the support pipe 1022. After the connecting pipe 1021 is inserted into the support pipe 1022, the threaded hole aligns with the limiting hole 8, and the positioning bolt 7 is screwed into the threaded hole and passes through the limiting hole 8. Thus, the positioning bolt 7 locks the connecting pipe 1021 and the support pipe 1022 together, thereby preventing slippage between the connecting pipe 1021 and the support pipe 1022.

[0044] According to the above plan:

[0045] On complex terrain such as slopes, the foot tube 102, consisting of the connecting tube 1021 and the support tube 1022, is placed on the lower side as slope support. Then, the positioning bolt 7 is loosened or removed to allow the connecting tube 1021 to be pulled out. The connecting tube 1021 is gradually pulled out of the support tube 1022 until the telescopic rod 3 aligns with the connecting hole 4. (Refer to the appendix.) Figure 6 As shown, at this time, the four telescopic rods 3 on both sides are pushed out by the springs and respectively embedded in the corresponding connecting holes 4, causing the connecting tube 1021 and the support tube 1022 to deflect relative to each other and maintain a stable connection in the deflected position. The state of the foot tube 102 at this time is as shown in the attached figure. Figure 4 As shown, a truss support is formed on the lower side of the slope. The support angle of the lower leg tube 102 is adjusted to extend the support range, thereby making the tripod 1 more stable.

[0046] When it is time to retract, press the telescopic rod 3 at the same time. The telescopic rod 3 will retract into the groove. At this time, the connecting pipe 1021 can be inserted into the support pipe 1022 again and tightened by the positioning bolt 7.

[0047] In this design, the connecting pipe 1021 can be solid or hollow; if hollow, the lower end where the elastic rod is located is solid. The support pipe 1022 can be solid or hollow; if solid, the upper end of the support pipe 1022 has an insertion hole for the connecting pipe 1021 to be inserted.

[0048] In this plan, refer to Appendix Figure 8 As shown, the connecting pipe 1021 is a reducing pipe. The outer wall of the part of the connecting pipe 1021 inserted into the support pipe 1022 fits against the inner wall of the support pipe 1022, so that the connecting pipe 1021 will not shake or become unstable due to gaps after being inserted into the support pipe 1022.

[0049] In this design, to facilitate the adjustment of the flow space by deflecting the connecting pipe 1021 relative to the supporting pipe 1022, the upper end of the supporting pipe 1022 is symmetrically provided with an upwardly extending support 5. The outer wall of the support 5 is arc-shaped, matching the inner wall of the supporting pipe 1022, and two sets of connecting holes 4 are provided on the support 5. The support 5 deflects the connecting pipe 1021 and the outer edge of the fixed part of the supporting pipe 1022, thereby providing sufficient adjustment space.

[0050] In this scheme, the outer wall of the support tube 1022 is provided with a threaded hole, and the part of the connecting tube 1021 inserted into the support tube 1022 is provided with a limiting hole 8 corresponding to the threaded hole. The positioning bolt 7 is screwed into the threaded hole and passes through the limiting hole 8, so that the positioning bolt 7 forms a connection and installation base between the connecting tube 1021 and the support tube 1022.

[0051] In Example 2, to extend the height of the leg tube 102 for conventional height adjustment of the measuring instrument 2, an extension leg 15 is fitted onto the leg tube 102. The extension leg 15 and the leg tube 102 form a telescopic tube structure. Height adjustment is achieved by extending and retracting the extension leg 15 on the leg tube 102. To maintain stability after the extension leg 15 is adjusted, a locking frame 16 is provided on the extension leg 15, and a locking bolt 18 is threaded onto the locking frame 16. After adjustment, the locking bolt 18 is tightened, and the locking bolt 18 abuts against the outer wall of the leg tube 102, thereby locking the extension leg 15. Preferably, a friction plate is provided on the contact surface of the locking bolt 18 to increase the contact area and thus increase the braking friction.

[0052] The reducing end of the connecting pipe 1021 is provided with a groove 6 that mates with the support 5. When the connecting pipe 1021 retracts into the support pipe 1022, the support 5 is engaged in the groove 6, so that there is no gap at the joint between the connecting pipe 1021 and the support pipe 1022, and the joint surface is smooth and flat, thus avoiding interference with the retraction of the extension leg 15.

[0053] The contact surface between the extension leg 15 and the leg tube 102 is provided with friction damping. This increases the moving friction braking force of the extension leg 15, thereby improving the connection stability between the extension leg 15 and the leg tube 102.

[0054] The bottom end of the extended support leg 15 is provided with a ground-inserting cone 17, which is inserted into the soil layer to improve the tightness of the tripod 1 on the ground and prevent slippage. The ground-inserting cone 17 is provided with a foot pedal for easy stepping and inserting into the ground.

[0055] Common tripod leg tubes 102 are primarily made of aluminum alloy and carbon fiber. To enhance the strength of the leg tubes 102, this design employs a double-tube support structure: both sides of the extended leg 15 have C-shaped grooves, each groove holding a leg tube 102. The upper ends of the two leg tubes 102 on the same extended leg 15 are connected to a connecting seat 9, and the lower ends are connected to a bridge frame 10. The connecting seat 9 is rotatably connected to the base 101 via a damping pivot. The bridge frame 10 has C-shaped buckles that secure the two leg tubes 102. This double-tube support provides symmetrical support in two rows, distributing pressure on one side and improving support strength and stability. For the leg tubes 102, which are divided into connecting tubes 1021 and support tubes 1022, the connecting tubes 1021 connect to the connecting seat 9. Since the support tube 1022 is longer, bridge frames 10 are installed at both ends of the support tube 1022 for double-end connection, improving connection stability.

[0056] Preferably, the buckle frame 16 is a straight groove frame, and the straight groove in the straight groove frame covers the two leg tubes 102 and the extension support 15 together. By increasing the connection points between the extension support 15 and the two sets of leg tubes 102 (support tubes 1022) through the buckle frame 16, the splicing tightness of the double tube support is improved.

[0057] In Example 3, to prevent the three sets of legs 102 of the triangular rubber from slipping during support and affecting installation stability, in this design, suspensions are provided between the rotating parts of the three sets of legs 102 on the lower end face of the base 101. A claw seat 11 is fixed to the bottom end of each of the three suspensions. The distance between the claw seat 11 and the base 101 satisfies the following conditions: sufficient vertical installation space is provided, but the installation bolts are not interfered with. A central shaft 12, which is a threaded shaft or lead screw, is rotatably mounted on the claw seat 11. A connecting ring 13 is threaded onto the central shaft 12, and a support rod 14, corresponding to each leg 102, is rotatably mounted on the outer edge of the connecting ring 13. The other end of the support rod 14 is rotatably connected to the bottom side wall of the leg 102. By turning the central shaft 12, the connecting ring 13 can be raised and lowered, and the support rod 14 can be used to pull and support the leg tube 102 to control the expansion and contraction of the leg tube 102, provide auxiliary support for the leg tube 102, and thus improve the assembly stability of the tripod 1.

[0058] In this design, at least one foot tube 102 is divided into a connecting tube 1021 and a support tube 1022 for extension and deflection adjustment to adapt to different terrains. To accommodate the retraction of the connecting tube 1021 and support tube 1022, the support rod 14 corresponding to the foot tube 102 (divided into a connecting tube 1021 and a support tube 1022) is divided into a screw barrel 1401 and a stud 1402. A U-shaped seat is rotatably connected to the upper end of the screw barrel 1401, and the U-shaped seat is rotatably connected to the connecting ring 13. The lower end of the stud 1402 is rotatably connected to the foot tube 102; the stud 1402 is threadedly connected to the screw barrel 1401. By screwing the screw barrel 1401 in this way, the extension and retraction of the stud 1402 within the screw barrel 1401 can be controlled. For normal ground use, refer to the attached diagram. Figure 3 As shown, a portion of the stud 1402 is retracted into the screw barrel 1401; when used on slopes or other terrain surfaces, refer to the attached diagram. Figure 4 As shown, screwing the screw barrel 1401 causes the stud 1402 to extend outward from the screw barrel 1401. The engagement of the stud 1402 with the screw barrel 1401 provides more operational space for leveling between the connecting pipe 1021 and the support pipe 1022.

[0059] Preferably, in this design, a single-point double-tube support structure is also provided to reinforce the tripod 1. At this time, the stud 1402 is rotatably mounted on the cable tray 10.

[0060] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

[0061] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0062] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A measuring device for electric power construction comprising a tripod (1) and a measuring instrument (2), characterized in that, The tripod (1) includes a base (101) for loading the measuring instrument (2), and three legs (102) rotatably mounted around the base (101) via a damping shaft. At least one leg (102) is divided into a support tube (1022) and a connecting tube (1021) embedded in the support tube (1022). A positioning bolt (7) is provided between the connecting tube (1021) and the support tube (1022). Two sets of telescopic rods (3) are radially slidably installed at the end of the connecting tube (1021). An elastic element is provided between the telescopic rod (3) and the connecting tube (1021). The upper end of the support tube (1022) is provided with connecting holes (4) corresponding to the telescopic rods (3).

2. The measuring device for electric power construction according to claim 1, characterized by The connecting pipe (1021) is a variable diameter pipe, and the outer wall of the part of the connecting pipe (1021) inserted into the support pipe (1022) is in contact with the inner wall of the support pipe (1022).

3. The measuring device for electric power construction according to claim 2, characterized by The upper end of the support tube (1022) is symmetrically provided with an extended support (5). The outer wall of the support (5) is an arc shape that matches the inner wall of the support tube (1022). Two sets of connecting holes (4) are provided on the support (5).

4. The measuring device for electric power construction according to claim 1, characterized by The outer wall of the support tube (1022) is provided with a threaded hole, and the part of the connecting tube (1021) inserted into the support tube (1022) is provided with a limiting hole (8) corresponding to the threaded hole. The positioning bolt (7) is screwed into the threaded hole and passes through the limiting hole (8).

5. The measuring device for electric power construction according to claim 2, characterized by The foot tube (102) is fitted with an extension foot (15), and the extension foot (15) is provided with a buckle frame (16), and a locking bolt (18) is screwed onto the buckle frame (16) and abuts against the outer wall of the foot tube (102).

6. The measuring device for electric power construction according to claim 5, wherein Both sides of the extended support leg (15) are provided with C-shaped grooves, and each groove is fitted with a leg tube (102). The upper ends of the two leg tubes (102) on the same extended support leg (15) are connected to a connecting seat (9), and the lower ends are connected to a cable tray (10). The connecting seat (9) is rotatably connected to the base (101) via a damping shaft. The cable tray (10) is provided with C-shaped buckles that cover the two leg tubes (102).

7. The measuring device for electric power construction according to claim 6, wherein The buckle frame (16) is a straight groove frame, and the straight groove in the straight groove frame will fasten the two leg tubes (102) and the extension leg (15) together.

8. The measuring device for electric power construction according to claim 5, wherein The contact surface between the extended support leg (15) and the foot tube (102) is provided with friction damping.

9. The measuring device for electric power construction according to claim 5, characterized by The outer diameter of the exposed part of the connecting pipe (1021) is the same as the outer diameter of the support pipe (1022), and the variable diameter end of the connecting pipe (1021) is provided with a groove (6) that cooperates with the support (5).

10. The measuring device for electric power construction according to claim 1, characterized by A claw seat (11) is suspended and fixed on the lower end face of the base (101). A central shaft (12) is rotatably mounted on the claw seat (11). A connecting ring (13) is threaded on the central shaft (12). A support rod (14) corresponding to the foot tube (102) is rotatably mounted on the outer edge of the connecting ring (13). The other end of the support rod (14) is rotatably connected to the bottom side wall of the foot tube (102). At least one support rod (14) is divided into a screw cylinder (1401) and a stud (1402).