Pesticide spraying device for plant protection unmanned aerial vehicle

Abstract

The invention discloses a pesticide spraying device for a plant protection unmanned aerial vehicle, and relates to the technical field of unmanned aerial vehicles, the pesticide spraying device comprises a pesticide box fixedly arranged on an unmanned aerial vehicle body, the unmanned aerial vehicle body comprises a rack, four connecting arms are symmetrically fixed to the side wall of the rack, and a driving box is fixed to the tail end of each connecting arm; a propeller is rotationally arranged on the upper end face of each driving box, a U-shaped seat is fixed to the lower end face of each driving box, an external hollow pipe is rotationally arranged on the inner wall of each U-shaped seat, an internal hollow pipe is movably arranged in each external hollow pipe, and a spraying head is fixed to the lower end of each internal hollow pipe; a conveying hose is arranged between each spraying head and the pesticide box in a communicating mode, and each U-shaped base is provided with a limiting assembly used in cooperation with an external hollow pipe. When pesticide is sprayed to crops, the spraying head can be closer to the crops, the flying height of the unmanned aerial vehicle body is higher, and the influence of wind power generated by the propellers on the crops is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicles, and in particular to a pesticide spraying device for a crop protection unmanned aerial vehicle. Background Art

[0002] Drone spraying of pesticides is an efficient and precise way of applying pesticides in modern agriculture. Drones have fast operation speed and high efficiency, which greatly saves manpower and material costs. Compared with traditional manual spraying methods, drone spraying can complete large-scale pesticide spraying tasks more quickly. Compared with traditional manual spraying, drone spraying can be remotely controlled, and people will not directly contact pesticides, which can protect people's health to a certain extent.

[0003] However, the existing pesticide spraying devices for plant protection drones have certain defects during use. For example, the spray head of the existing spraying device is fixedly arranged below the propeller of the drone, and the distance between the two is relatively close. In order to enable the spray head to spray pesticides on the crops below, the flight altitude of the drone is relatively low, and the wind force generated by the propeller will cause the crops below to bend and tilt, resulting in a general spraying effect of the pesticide. Summary of the invention

[0004] The purpose of the present invention is to solve the problems existing in the prior art:

[0005] When the existing pesticide spraying device is used in conjunction with a drone, the drone flies at a relatively low altitude, and the wind force generated by the propeller causes the crops below to bend and tilt, resulting in poor pesticide spraying results.

[0006] A pesticide spraying device for a crop protection drone is proposed.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A pesticide spraying device for a crop protection UAV comprises a medicine box fixedly arranged on a UAV body, wherein the UAV body comprises a frame, four connecting arms are symmetrically fixed on the side walls of the frame, a driving box is fixed to the end of each connecting arm, a propeller is rotatably arranged on the upper end surface of each driving box, a U-shaped seat is fixed to the lower end surface of each driving box, an external hollow tube is rotatably arranged on the inner wall of each U-shaped seat, an internal hollow tube is movably arranged in the external hollow tube, a spray head is fixed to the lower end of the internal hollow tube, a delivery hose is connected between each spray head and the medicine box, and a limit assembly used in conjunction with the external hollow tube is arranged on each U-shaped seat.

[0009] As a further technical solution of the present invention, a plurality of limit sliding blocks are fixed on the outer wall of each of the inner hollow tubes, and a plurality of limit sliding grooves for cooperating with the limit sliding blocks are symmetrically provided on the inner wall of each of the outer hollow tubes.

[0010] As a further technical solution of the present invention, the outer surface of each of the spray heads is movably provided with a lifting sleeve, the lower end surface of each lifting sleeve is detachably provided with a wear-resistant ring, and the outer side wall of each internal hollow tube is provided with a driving unit and a guide unit for use with the lifting sleeve.

[0011] As a further technical solution of the present invention, each of the driving units includes a pad fixed to one side of the internal hollow tube, an electric push rod is fixed to one side of the pad, a connecting block is fixed to the outer surface of the lifting sleeve, and the end of the telescopic end of the electric push rod is fixedly connected to the upper end surface of the connecting block.

[0012] As a further technical solution of the present invention, each of the guide units includes a guide seat fixed to one side of the internal hollow tube, a connecting block 2 is fixed to the outer surface of the lifting sleeve, a guide rod is fixed to the upper end surface of the connecting block 2, and the upper end of the guide rod movably passes through the guide seat.

[0013] As a further technical solution of the present invention, each of the limiting components includes two movable rods that penetrate the side walls of the U-shaped seat, one end of each movable rod is fixed with an insertion column, the other end of each movable rod is fixed with a pull block, and two fixed seats are symmetrically fixed on the side wall of the external hollow tube, and each fixed seat is provided with an insertion groove for cooperating with the insertion column on one side close to the insertion column, and each insertion groove is provided with a limiting unit for cooperating with the insertion column.

[0014] As a further technical solution of the present invention, each of the limiting units includes a magnet layer 1 fixed on the inner wall of the insertion groove, and a magnet layer 2 is fixed to the end of each insertion column, and the magnet layer 1 and the magnet layer 2 are magnetically attracted to each other.

[0015] As a further technical solution of the present invention, the outer surface of each connecting arm is fixed with U-shaped frame 1 and U-shaped frame 2 used in conjunction with the conveying hose, and the side wall of each external hollow tube is provided with a side through groove used in conjunction with the conveying hose, and one end of the conveying hose passes through U-shaped frame 1, U-shaped frame 2 and the side through groove in sequence.

[0016] As a further technical solution of the present invention, an elastic block is fixed on the upper end face of each electric push rod, a connecting seat is fixed on the side wall of each external hollow tube, and an elastic slot is provided on the lower end face of each connecting seat for use with the elastic block.

[0017] As a further technical solution of the present invention, each of the lower end faces of the U-shaped frames 2 is provided with a notch, and a plurality of elastic card slots 2 are symmetrically provided on the inner wall of each notch, and a plurality of elastic card blocks 2 are fixed on both sides of each connecting seat for use with the corresponding elastic card slots 2.

[0018] Beneficial effects of the present invention:

[0019] 1. When the medicine box is filled with the pesticide to be sprayed, the outer hollow tube and the inner hollow tube are in a vertical downward state, and the outer hollow tube is limited and fixed by the limit assembly. When the drone body takes off, the inner hollow tube and the spray head continue to move downward for a distance under the action of gravity, so that the spray head is closer to the crops, so that the drone body can fly higher, reducing the impact of the wind generated by the propeller on the crops, so as to achieve better effect of pesticide spraying.

[0020] 2. After the drone takes off, the telescopic end of the electric push rod contracts, prompting the lifting sleeve to move upward, so that the working area of ​​the spray head is exposed, and the pesticide is sprayed. When the pesticide in the medicine box is sprayed, the drone is ready to land for refilling. At this time, the telescopic end of the electric push rod extends, and the lower end surface of the lifting sleeve is lower than the lower end surface of the spray head, so that the wear-resistant ring contacts the ground first, avoiding the spray head from colliding with the ground, and protecting the spray head. Under the resistance of the ground, the wear-resistant ring, the lifting sleeve, and the internal hollow tube are moved upward relative to the external hollow tube until the landing gear of the drone body contacts the ground.

[0021] 3. When in use, after the external hollow tube is rotated to a vertical downward position, the staff pushes the pull block toward the direction close to the external hollow tube, thereby pushing the moving rod and the plug-in column toward the direction close to the external hollow tube, until the plug-in column brings the magnet layer 2 into the plug-in slot, until the magnet layer 2 and the magnet layer 1 are magnetically attracted together to prevent the plug-in column from falling off the plug-in slot, thereby limiting the external hollow tube and restricting its continued rotation, which is easy to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the connection between the rack and the medicine box in the present invention Figure 1 ;

[0023] Figure 2 Schematic diagram of the connection between the rack and the medicine box in the present invention Figure 2 ;

[0024] Figure 3 It is a schematic diagram of the connection between the internal hollow tube and the spray head in the present invention;

[0025] Figure 4 It is a schematic diagram of the connection between the drive box and the U-shaped seat in the present invention;

[0026] Figure 5 It is a schematic diagram of the internal structure of the insertion slot in the present invention;

[0027] Figure 6 It is a structural schematic diagram of the U-shaped frame 2 in the present invention.

[0028] In the figure: 1. UAV body; 2. frame; 3. connecting arm; 4. drive box; 5. propeller; 6. U-shaped seat; 7. external hollow tube; 8. internal hollow tube; 9. spray head; 10. delivery hose; 11. limit slider; 12. lifting sleeve; 13. wear-resistant ring; 14. pad; 15. electric push rod; 16. connecting block 1; 17. guide seat; 18. connecting block 2; 19. guide rod; 20. moving rod; 21. plug-in column; 22. pull block; 23. fixed seat; 24. plug-in slot; 25. magnet layer 1; 26. magnet layer 2; 27. U-shaped frame 1; 28. U-shaped frame 2; 29. ​​side through slot; 30. elastic block 1; 31. connecting seat; 33. missing slot; 34. elastic card slot 2; 35. elastic card block 2; 36. medicine box. DETAILED DESCRIPTION

[0029] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation mode, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0030] Reference Figure 1-Figure 6 A pesticide spraying device for a crop protection drone comprises a medicine box 36 fixedly arranged on a drone body 1. The drone body 1 comprises a frame 2. Four connecting arms 3 are symmetrically fixed on the side wall of the frame 2. A driving box 4 is fixed at the end of each connecting arm 3. A propeller 5 is rotatably arranged on the upper end surface of each driving box 4. A U-shaped seat 6 is fixed on the lower end surface of each driving box 4. An external hollow tube 7 is rotatably arranged on the inner wall of each U-shaped seat 6. An internal hollow tube 8 is movably arranged in the external hollow tube 7. A spraying head 9 is fixed at the lower end of the internal hollow tube 8. A conveying hose 10 is connected between each spraying head 9 and the medicine box 36. The conveying hose 10 in the external hollow tube 7 and the internal hollow tube 8 is long enough. A limiting assembly used in conjunction with the external hollow tube 7 is arranged on each U-shaped seat 6. A conveying pump and a tap used in conjunction with the conveying hose 10 are arranged in the medicine box 36. Spraying pesticides by using the drone body 1 is an existing technology.

[0031] Reference Figure 1 and Figure 2When the medicine box 36 is filled with the pesticide to be sprayed, the outer hollow tube 7 and the inner hollow tube 8 are in a vertical downward state, and the outer hollow tube 7 is limited and fixed by the limit assembly. When the drone body 1 takes off, the inner hollow tube 8 and the spray head 9 continue to move downward for a distance under the action of gravity, so that the spray head 9 is closer to the crops, so that the drone body 1 can fly higher, reducing the impact of the wind generated by the propeller 5 on the crops, so as to achieve a better effect of pesticide spraying.

[0032] Reference Figure 3 A plurality of limit slide blocks 11 are fixed on the outer wall of each inner hollow tube 8 , and a plurality of limit slide grooves for cooperating with the limit slide blocks 11 are symmetrically opened on the inner wall of each outer hollow tube 7 .

[0033] The cooperation between the limiting sliding block 11 and the limiting sliding groove can prevent the inner hollow tube 8 from falling off from the outer hollow tube 7 .

[0034] Reference Figure 3 The outer surface of each spray head 9 is movably provided with a lifting sleeve 12, and the lower end surface of each lifting sleeve 12 is detachably provided with a wear-resistant ring 13, and the outer side wall of each internal hollow tube 8 is provided with a driving unit and a guide unit used in conjunction with the lifting sleeve 12.

[0035] Reference Figure 3 Each driving unit includes a pad 14 fixed to one side of the internal hollow tube 8, an electric push rod 15 is fixed to one side of the pad 14, a connecting block 16 is fixed to the outer surface of the lifting sleeve 12, and the end of the telescopic end of the electric push rod 15 is fixedly connected to the upper end surface of the connecting block 16.

[0036] Reference Figure 1-Figure 3 After the drone body 1 takes off, the telescopic end of the electric push rod 15 contracts, prompting the lifting sleeve 12 to move upward, so that the working area of ​​the spray head 9 is exposed, and the pesticide is sprayed. When the pesticide in the medicine box 36 is sprayed, the drone body 1 is ready to land to replenish the pesticide. At this time, the telescopic end of the electric push rod 15 is extended, and the lower end surface of the lifting sleeve 12 is lower than the lower end surface of the spray head 9, so that the wear-resistant ring 13 first contacts the ground to prevent the spray head 9 from colliding with the ground. The spray head 9 is protected by a cover. Under the resistance of the ground, the wear-resistant ring 13, the lifting sleeve 12, and the internal hollow tube 8 are moved upward relative to the external hollow tube 7 until the landing gear of the drone body 1 contacts the ground.

[0037] Reference Figure 3 Each guide unit includes a guide seat 17 fixed to one side of the internal hollow tube 8, a connecting block 18 is fixed to the outer surface of the lifting sleeve 12, a guide rod 19 is fixed to the upper end surface of the connecting block 18, and the upper end of the guide rod 19 movably passes through the guide seat 17.

[0038] By means of the cooperation of the guide seat 17 and the guide rod 19, the lifting and lowering movement of the lifting sleeve 12 is limited and guided, thereby ensuring the stability of the lifting sleeve 12 during the lifting process.

[0039] Reference Figure 1 , Figure 4 and Figure 5 Each limiting assembly includes two moving rods 20 that movably penetrate the side walls of the U-shaped seat 6, one end of each moving rod 20 is fixed with an insertion column 21, and the other end of each moving rod 20 is fixed with a pull block 22. Two fixed seats 23 are symmetrically fixed on the side wall of the external hollow tube 7, and each fixed seat 23 is provided with an insertion groove 24 used to cooperate with the insertion column 21 on one side close to the insertion column 21, and each insertion groove 24 is provided with a limiting unit used to cooperate with the insertion column 21.

[0040] Reference Figure 5 Each limiting unit includes a magnet layer 1 25 fixed on the inner wall of the insertion groove 24, and a magnet layer 2 26 is fixed to the end of each insertion column 21, and the magnet layer 1 25 and the magnet layer 2 26 are magnetically attracted to each other.

[0041] Reference Figure 1 , Figure 4 and Figure 5 When in use, after the external hollow tube 7 is rotated to a vertically downward state, the staff pushes the pull block 22 in the direction close to the external hollow tube 7, thereby pushing the moving rod 20 and the plug-in column 21 to move in the direction close to the external hollow tube 7, until the plug-in column 21 brings the magnet layer 26 into the plug-in groove 24, until the magnet layer 26 and the magnet layer 1 25 are magnetically attracted together, preventing the plug-in column 21 from falling off from the plug-in groove 24, thereby limiting and fixing the external hollow tube 7 and restricting its continued rotation, which is convenient to use.

[0042] Reference Figure 1 and Figure 2 The outer surface of each connecting arm 3 is fixed with a U-shaped frame 1 27 and a U-shaped frame 28 used in conjunction with the conveying hose 10, and the side wall of each external hollow tube 7 is provided with a side through groove 29 used in conjunction with the conveying hose 10, and one end of the conveying hose 10 passes through the U-shaped frame 1 27, the U-shaped frame 28 and the side through groove 29 in sequence.

[0043] The delivery hose 10 is supported by the cooperation of the U-shaped frame 1 27 and the U-shaped frame 2 28 .

[0044] Reference Figure 1 , Figure 3 and Figure 4An elastic block 30 is fixed to the upper end surface of each electric push rod 15, a connecting seat 31 is fixed to the side wall of each external hollow tube 7, and an elastic slot 1 for matching with the elastic block 30 is opened on the lower end surface of each connecting seat 31.

[0045] Reference Figure 6 The lower end surface of each U-shaped frame 28 is provided with a notch 33, and the inner wall of each notch 33 is symmetrically provided with a plurality of elastic card slots 2 34, and both sides of each connecting seat 31 are fixed with a plurality of elastic card blocks 2 35 used in conjunction with the corresponding elastic card slots 2 34.

[0046] Reference Figure 1 , Figure 3 , Figure 4 and Figure 6 After the use of the drone body 1 is finished, the internal hollow tube 8 is moved upward, and the internal hollow tube 8 moves upward together with the electric push rod 15 and the elastic card block 1 30 until the elastic card block 1 30 is engaged in the elastic card slot 1 below the connecting seat 31. The internal hollow tube 8 in this state is limited and fixed by the cooperation of the set elastic card block 1 30 and the elastic card slot 1, and then the limit fixation of the external hollow tube 7 by the limit assembly is released, and then the external hollow tube 7 is rotated 90° toward the direction of the connecting arm 3 until the elastic card block 2 35 on the connecting seat 31 is engaged in the elastic card slot 2 34 in the missing groove 33. The external hollow tube 7 in this state is limited and fixed by the cooperation of the set elastic card block 2 35 and the elastic card slot 2 34, so as to facilitate the subsequent storage and transportation of the drone body 1.

[0047] When the present invention is used, refer to Figure 1 and Figure 2 When the medicine box 36 is filled with the pesticide to be sprayed, the outer hollow tube 7 and the inner hollow tube 8 are in a vertical downward state, and the outer hollow tube 7 is limited and fixed by the limit assembly. When the drone body 1 takes off, the inner hollow tube 8 and the spray head 9 continue to move downward for a distance under the action of gravity, so that the spray head 9 is closer to the crops, so that the drone body 1 can fly higher, reduce the impact of the wind force generated by the propeller 5 on the crops, and achieve a better effect of pesticide spraying;

[0048] Reference Figure 1-Figure 3When the drone body 1 takes off, the telescopic end of the electric push rod 15 contracts, prompting the lifting sleeve 12 to move upward, so that the working area of ​​the spray head 9 is exposed, and the pesticide is sprayed. When the pesticide in the medicine box 36 is sprayed, the drone body 1 is ready to land to refill the pesticide. At this time, the telescopic end of the electric push rod 15 is extended, and the lower end surface of the lifting sleeve 12 is lower than the lower end surface of the spray head 9, so that the wear-resistant ring 13 first contacts the ground to prevent the spray head 9 from colliding with the ground. The spray head 9 is protected by a cover. Under the resistance of the ground, the wear-resistant ring 13, the lifting sleeve 12, and the internal hollow tube 8 are moved upward relative to the external hollow tube 7 until the landing gear of the drone body 1 contacts the ground;

[0049] Reference Figure 1 , Figure 4 and Figure 5 When in use, after the outer hollow tube 7 is rotated to a vertical downward state, the staff pushes the pull block 22 in the direction close to the outer hollow tube 7, thereby pushing the moving rod 20 and the plug-in column 21 to move in the direction close to the outer hollow tube 7, until the plug-in column 21 brings the second magnet layer 26 into the plug-in slot 24, until the second magnet layer 26 and the first magnet layer 25 are magnetically attracted together, so as to prevent the plug-in column 21 from falling off from the plug-in slot 24, thereby limiting and fixing the outer hollow tube 7, and limiting its continued rotation, which is convenient to use;

[0050] Reference Figure 1 , Figure 3 , Figure 4 and Figure 6 After the use of the drone body 1 is finished, the internal hollow tube 8 is moved upward, and the internal hollow tube 8 moves upward together with the electric push rod 15 and the elastic card block 1 30 until the elastic card block 1 30 is engaged in the elastic card slot 1 below the connecting seat 31. The internal hollow tube 8 in this state is limited and fixed by the cooperation of the set elastic card block 1 30 and the elastic card slot 1, and then the limit fixation of the external hollow tube 7 by the limit assembly is released, and then the external hollow tube 7 is rotated 90° toward the direction of the connecting arm 3 until the elastic card block 2 35 on the connecting seat 31 is engaged in the elastic card slot 2 34 in the missing groove 33. The external hollow tube 7 in this state is limited and fixed by the cooperation of the set elastic card block 2 35 and the elastic card slot 2 34, so as to facilitate the subsequent storage and transportation of the drone body 1.

[0051] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A pesticide spraying device for a crop protection drone, comprising a pesticide box (36) fixedly mounted on a drone body (1), characterized in that: The drone body (1) comprises a frame (2), four connecting arms (3) are symmetrically fixed on the side wall of the frame (2), a driving box (4) is fixed at the end of each connecting arm (3), a propeller (5) is rotatably provided on the upper end surface of each driving box (4), a U-shaped seat (6) is fixed on the lower end surface of each driving box (4), an external hollow tube (7) is rotatably provided on the inner wall of each U-shaped seat (6), an internal hollow tube (8) is movably provided in the external hollow tube (7), a spray head (9) is fixed at the lower end of the internal hollow tube (8), a conveying hose (10) is provided between each spray head (9) and a medicine box (36), and a limit assembly used in conjunction with the external hollow tube (7) is provided on each U-shaped seat (6).

2. The pesticide spraying device for a crop protection drone according to claim 1, characterized in that: A plurality of limit slide blocks (11) are fixed on the outer wall of each of the inner hollow tubes (8), and a plurality of limit slide grooves for cooperating with the limit slide blocks (11) are symmetrically provided on the inner wall of each of the outer hollow tubes (7).

3. The pesticide spraying device for a crop protection drone according to claim 1, characterized in that: The outer surface of each of the spray heads (9) is movably provided with a lifting sleeve (12), the lower end surface of each lifting sleeve (12) is detachably provided with a wear-resistant ring (13), and the outer side wall of each internal hollow tube (8) is provided with a driving unit and a guide unit used in conjunction with the lifting sleeve (12).

4. The pesticide spraying device for a crop protection drone according to claim 3, characterized in that: Each of the driving units comprises a pad (14) fixed to one side of the internal hollow tube (8), an electric push rod (15) is fixed to one side of the pad (14), a connecting block (16) is fixed to the outer surface of the lifting sleeve (12), and the end of the telescopic end of the electric push rod (15) is fixedly connected to the upper end surface of the connecting block (16).

5. The pesticide spraying device for a crop protection drone according to claim 3, characterized in that: Each of the guide units comprises a guide seat (17) fixed to one side of the internal hollow tube (8); a connecting block 2 (18) is fixed to the outer surface of the lifting sleeve (12); a guide rod (19) is fixed to the upper end surface of the connecting block 2 (18); and the upper end of the guide rod (19) movably passes through the guide seat (17).

6. The pesticide spraying device for a crop protection drone according to claim 1, characterized in that: Each of the limiting components comprises two movable rods (20) which are movably inserted through the side wall of the U-shaped seat (6); a plug-in column (21) is fixed to one end of each movable rod (20); a pull block (22) is fixed to the other end of each movable rod (20); two fixed seats (23) are symmetrically fixed on the side wall of the external hollow tube (7); a plug-in groove (24) for cooperating with the plug-in column (21) is provided on one side of each fixed seat (23) close to the plug-in column (21); and a limiting unit for cooperating with the plug-in column (21) is provided in each plug-in groove (24).

7. The pesticide spraying device for a crop protection drone according to claim 6, characterized in that: Each of the limiting units comprises a first magnet layer (25) fixed on the inner wall of the insertion groove (24), and a second magnet layer (26) is fixed at the end of each insertion column (21), and the first magnet layer (25) and the second magnet layer (26) are magnetically attracted to each other.

8. The pesticide spraying device for a crop protection drone according to claim 4, characterized in that: The outer surface of each connecting arm (3) is fixed with a U-shaped frame 1 (27) and a U-shaped frame 2 (28) for use with the conveying hose (10), and the side wall of each external hollow tube (7) is provided with a side through groove (29) for use with the conveying hose (10), and one end of the conveying hose (10) passes through the U-shaped frame 1 (27), the U-shaped frame 2 (28) and the side through groove (29) in sequence.

9. The pesticide spraying device for a crop protection drone according to claim 8, characterized in that: An elastic card block (30) is fixed to the upper end surface of each electric push rod (15), a connecting seat (31) is fixed to the side wall of each external hollow tube (7), and an elastic card slot (31) is provided on the lower end surface of each connecting seat (31) for use with the elastic card block (30).

10. The pesticide spraying device for a crop protection drone according to claim 9, characterized in that: The lower end surface of each U-shaped frame (28) is provided with a notch (33), and the inner wall of each notch (33) is symmetrically provided with a plurality of elastic clamping grooves (34). Both sides of each connecting seat (31) are fixed with a plurality of elastic clamping blocks (35) used in conjunction with the corresponding elastic clamping grooves (34).

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