House structure beam bottom reinforcing device

Abstract

The invention relates to the technical field of buildings, in particular to a house structure beam bottom reinforcing device. Comprising a fixing frame, extending frames are slidably connected to the two ends of the fixing frame, a transmission mechanism used for driving the extending frames to move is installed on the inner side of the fixing frame, and the transmission mechanism comprises a rotating disc, a first rotating column, a second rotating column, a threaded rod, an adjusting driving motor, an adjusting worm and an adjusting worm wheel; a second rotating column is rotationally connected into the other end of the fixing frame, and a rotating disc is fixed to the end, close to the second rotating column, of the first rotating column. According to the house structure beam bottom reinforcing device, through cooperation of the fixing frame, the extending frames and the reinforcing plate, work of the transmission mechanism can drive the two extending frames to move away from the fixing frame, then the device can be fixed to the house structure beam bottom, and meanwhile the house structure beam bottom is supported through rising of the reinforcing plate.

Description

Technical Field

[0001] The invention relates to the technical field of construction, and in particular to a beam bottom reinforcement device for a building structure. Background Art

[0002] During the construction of a house, the structural beam is the main support point of the house. In order to ensure the long-term use of the house, the bottom of the structural beam of the house needs to be reinforced. In the prior art, a tripod welded with angle steel is used to reinforce the structural beam of the building.

[0003] For example, the patent (CN113323437A) discloses a bottom reinforcement device for a building structure beam, including a supporting mechanism opposite to the left and right sides of the beam, the supporting mechanism including a horizontal plate, a vertical plate and a rotating shaft, the horizontal plate is located above the vertical plate, the vertical plate is located between the beam and the horizontal plate, a first cylinder is provided on the far upper side of the vertical plate, a second cylinder coaxial with the first cylinder is provided on the horizontal plate, the rotating shaft is coaxial with the first cylinder and the rotating shaft is inserted into the first cylinder and the second cylinder, the rotating shaft is respectively slidably fitted with the inner side walls of the first cylinder and the second cylinder, a viscous damper is connected between the horizontal plate and the vertical plate, and a spring cylinder is connected between the horizontal plate and the vertical plate; it also includes a carbon fiber cloth, the two ends of the carbon fiber cloth are in the shape of a triangle with an arc corner, and the carbon fiber cloth is in the shape of a U; it effectively solves the problem in the prior art that the carbon fiber reinforcement cannot adaptively adjust the supporting force of the beam according to the current state of the building and cannot absorb the kinetic energy when the building shakes; When using the above technology, it is found that the following technical problems exist in the prior art: the fixing and supporting effects of the existing reinforcement device after being installed at the bottom of the house beam are not good enough. Therefore, a house structure beam bottom reinforcement device is designed to provide another technical solution to the above technical problems. Summary of the invention

[0004] Based on this, it is necessary to provide a building structure beam bottom reinforcement device to address the above technical problems, so as to solve the technical problem that the existing reinforcement device has insufficient fixing and supporting effects after being installed at the bottom of the building beam.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: The cam is an electrically-operated transmission mechanism which is adapted to move the first and second frames to move the first and second frames to move the first and second frames to move the second frames to move the second frames.

[0006] As a preferred embodiment of the building structure beam bottom reinforcement device provided by the present invention, guide rods are fixed to the four end corners at both ends of the fixing frame, and the fixing frame is slidably connected to the extension frame through the guide rods.

[0007] As a preferred embodiment of the building structure beam bottom reinforcement device provided by the present invention, a synchronous assembly for connecting the rotating disk is installed at one end of the second rotating column close to the first rotating column, and the synchronous assembly comprises a synchronous block, a movable column, an anti-slip block, a sliding sleeve, a connecting rod, a movable plate and a compression spring, and a synchronous block is fixed to one end of the second rotating column close to the first rotating column, and the outer side of the synchronous block is slidably connected to the rotating disk, and the inner sides of the synchronous block are slidably connected to the movable column, and the outer side of the movable column is fixed with an anti-slip block, and the anti-slip block is slidably connected to the rotating disk, and the outer side of the second rotating column close to one end of the synchronous block is slidably connected to the sliding sleeve, and the two sides of the sliding sleeve are rotatably connected to the connecting rod, and the connecting rod is rotatably connected to the anti-slip block, and the outer side of the second rotating column and the end of the sliding sleeve away from the synchronous block is sleeved with a compression spring, and the outer side of the sliding sleeve is rotatably connected to the movable plate, and the movable plate is slidably connected to the fixed frame.

[0008] As a preferred embodiment of the building structure beam bottom reinforcement device provided by the present invention, an anti-slip groove is provided at one end of the inner side of the rotating disk close to the first rotating column, and the synchronization block is slidably connected to the rotating disk through the anti-slip groove.

[0009] As a preferred embodiment of the building structure beam bottom reinforcement device provided by the present invention, synchronization grooves are evenly distributed on the inner side of the rotating disk and at positions corresponding to the anti-detachment blocks, and the anti-detachment blocks are slidably connected to the rotating disk through the synchronization grooves.

[0010] As a preferred embodiment of the building structure beam bottom reinforcement device provided by the present invention, fixed shells are fixed at both ends of the top of the fixed frame, reinforcement plates are arranged on the tops of the two fixed shells, and a supporting mechanism is installed inside each of the fixed shells.

[0011] As a preferred embodiment of the building structure beam bottom reinforcement device provided by the present invention, the supporting mechanism includes a transmission gear, a rotating gear, a connecting column, an extrusion rod and a sliding block. The bottom end inside one end of the fixed shell is rotatably connected with a transmission gear, and the transmission gear is meshingly connected with the extension frame. The top of the transmission gear and the interior of the fixed shell are meshingly connected with a rotating gear. A connecting column is fixed inside the rotating gear, and the connecting column is rotatably connected to the fixed shell. An extrusion rod is fixed on the outside of the connecting column and located between the two rotating gears. The extrusion rod is slidably connected to the fixed shell, and the end of the extrusion rod away from the connecting column is rotatably connected with a sliding block, and the sliding block is slidably connected to the reinforcement plate.

[0012] As a preferred embodiment of the building structure beam bottom reinforcement device provided by the present invention, a toothed groove is provided at the top of the extension frame and at a position corresponding to the transmission gear, and the extension frame is meshed and connected with the transmission gear through the toothed groove.

[0013] It can be seen without a doubt that the above-mentioned technical solution of the present application can definitely solve the technical problem to be solved by the present application.

[0014] At the same time, through the above technical solutions, the present invention has at least the following beneficial effects: The present invention provides a building structure beam bottom reinforcement device, which can drive the two extension frames to move away from the fixed frame through the cooperation of the fixed frame, the extension frame and the reinforcement plate, so that the device can be fixed on the building structure beam bottom, and the building structure beam bottom is supported by the rising of the reinforcement plate; Through the cooperation of the rotating disk, the first rotating column, the second rotating column and the threaded rod, the rotation of the first rotating column drives the second rotating column to rotate simultaneously through the rotating disk, and then the two threaded rods with opposite rotation directions rotate simultaneously to drive the extension frame to move away from or close to the fixed frame at the same time, and the movement of the threaded rod drives the extrusion rod to rotate, so as to adjust the height of the reinforcement plate; When the bottom of the building structure beam is inclined, the anti-detachment block is separated from the slidingly connected rotating disk by translating the movable plate, so that the first rotating column can rotate alone, thereby driving the corresponding extension frame to move away from the fixed frame alone, thereby tilting the top of the reinforcement plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic diagram of the supporting effect of the present invention; Figure 3 It is a structural schematic diagram of the toothed groove of the present invention; Figure 4 is a schematic structural diagram of a second rotating column of the present invention; Figure 5 It is a structural schematic diagram of the sliding groove of the present invention; Figure 6 It is a schematic diagram of the internal structure of the rotating disk of the present invention; Figure 7 It is a schematic diagram of the internal structure of the synchronization block of the present invention; Figure 8 It is a schematic diagram of the internal structure of the fixed shell of the present invention.

[0017] In the figure: 1. fixed frame; 2. extension frame; 3. fixed shell; 4. reinforcement plate; 5. guide rod; 6. toothed groove; 7. displacement column; 8. rotating disk; 9. first rotating column; 10. second rotating column; 11. sliding groove; 12. threaded rod; 13. adjusting drive motor; 14. adjusting worm; 15. adjusting worm wheel; 16. anti-slip groove; 17. synchronous groove; 18. synchronous block; 19. moving column; 20. anti-slip block; 21. sliding sleeve; 22. connecting rod; 23. moving plate; 24. compression spring; 25. transmission gear; 26. rotating gear; 27. connecting column; 28. extrusion rod; 29. ​​sliding block. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings.

[0020] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features and technical solutions in the embodiments may be combined with each other.

[0021] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0022] Embodiment 1 Reference Figure 1-Figure 7 , a building structure beam bottom reinforcement device, including a fixed frame 1, both ends of the fixed frame 1 are slidably connected with an extension frame 2, four end corners of both ends of the fixed frame 1 are fixed with guide rods 5, the fixed frame 1 and the extension frame 2 are slidably connected through the guide rods 5, so that the extension frame 2 can be more stable when moving towards or away from the fixed frame 1, and a transmission mechanism for driving the extension frame 2 to move is installed on the inner side of the fixed frame 1, the transmission mechanism includes a rotating disk 8, a first rotating column 9, a second rotating column 10, a threaded rod 12, an adjustment drive motor 13, an adjustment worm 14 and an adjustment worm wheel 15, the internal rotation of one end of the fixed frame 1 is connected to the first rotating column 9, and the internal rotation of the other end of the fixed frame 1 is connected to the second rotating column 10, so that the rotation of the first rotating column 9 and the second rotating column 10 can be supported by the fixed frame 1, and the rotation is more stable; A rotating disk 8 is fixed to one end of the first rotating column 9 close to the second rotating column 10, so that the rotation of the first rotating column 9 drives the second rotating column 10 to rotate synchronously through the rotating disk 8, and a threaded rod 12 is fixed to one end of the first rotating column 9 and the second rotating column 10 away from each other, and the outer side of the threaded rod 12 away from the rotating disk 8 is threadedly connected with a displacement column 7, and the displacement column 7 is fixed to the extension frame 2, so that the rotation of the threaded rod 12 drives the extension frame 2 to move through the displacement column 7, and an adjusting drive motor 13 is fixed inside one end of the fixed frame 1, and an adjusting worm 14 is connected to the output end of the adjusting drive motor 13, and an adjusting worm wheel 15 is meshedly connected to one side of the adjusting worm 14, and the inner side of the adjusting worm wheel 15 is fixed to the first rotating column 9, so that the operation of the adjusting drive motor 13 drives the first rotating column 9 to rotate through the cooperation of the adjusting worm 14 and the adjusting worm wheel 15; The end of the second rotating column 10 close to the first rotating column 9 is equipped with a synchronization component for connecting the rotating disk 8, and the synchronization component includes a synchronization block 18, a moving column 19, an anti-slip block 20, a sliding sleeve 21, a connecting rod 22, a moving plate 23 and a compression spring 24. The end of the second rotating column 10 close to the first rotating column 9 is fixed with a synchronization block 18, and the outer side of the synchronization block 18 is slidably connected with the rotating disk 8, so that the synchronization block 18 can rotate and slide inside the rotating disk 8. An anti-slip groove 16 is provided on the inner side of the rotating disk 8 close to the first rotating column 9. The synchronization block 18 is slidably connected with the rotating disk 8 through the anti-slip groove 16, so that the synchronization block 18 will not be separated from the rotating disk 8 through the cooperation of the anti-slip groove 16, but the synchronization block 18 can rotate on the inner side of the rotating disk 8; The inside of both sides of the synchronous block 18 are slidably connected with moving columns 19, and the outside of the moving column 19 is fixed with an anti-dropping block 20, and the anti-dropping block 20 is slidably connected with the rotating disk 8, so that when the anti-dropping block 20 is located on the inner side of the rotating disk 8, the rotation of the rotating disk 8 drives the synchronous block 18 to rotate, and the synchronous block 18 drives the second rotating column 10 to rotate, and the inner side of the rotating disk 8 and the position corresponding to the anti-dropping block 20 are uniformly provided with synchronous grooves 17, and the anti-dropping block 20 is slidably connected with the rotating disk 8 through the synchronous grooves 17, so that whether the rotating disk 8 can drive the second rotating column 10 to rotate at the same time can be determined by whether the anti-dropping block 20 is located inside the synchronous grooves 17; A sliding sleeve 21 is slidably connected to the outer side of one end of the second rotating column 10 close to the synchronous block 18, so that the sliding sleeve 21 can rotate and slide translationally on the outer side of the second rotating column 10, and connecting rods 22 are rotatably connected to both sides of the sliding sleeve 21, and the connecting rods 22 are rotatably connected to the anti-slip block 20, so that the movement of the sliding sleeve 21 drives the movement of the anti-slip block 20 on the inner side of the synchronous block 18 through the connecting rods 22; A compression spring 24 is sleeved on the outer side of the second rotating column 10 and located at the end of the sliding sleeve 21 away from the synchronous block 18, so that the movement of the sliding sleeve 21 drives the compression spring 24 to be compressed under the obstruction of the fixed frame 1, so that the anti-slip block 20 is detached from the sliding connection with the rotating disk 8, and the outer side of the sliding sleeve 21 is rotatably connected with a moving plate 23, and the moving plate 23 is slidably connected to the fixed frame 1. A sliding groove 11 is provided inside the bottom end of the fixed frame 1 and at a position corresponding to the moving plate 23. The moving plate 23 is slidably connected to the fixed frame 1 through the sliding groove 11, so that the bottom of the moving plate 23 extends out of the fixed frame 1 through the sliding groove 11, so that the operator drives the translation of the moving plate 23 on the outer side of the fixed frame 1 to drive the anti-slip block 20 to detach from the slidably connected rotating disk 8.

[0023] The use process of the building structure beam bottom reinforcement device provided by the present invention is as follows: when in use, when the fixed frame 1 is located at the bottom of the building structure beam bottom that needs to be supported, the adjusting worm 14 is driven to rotate by adjusting the driving motor 13 to obtain power, so that the rotation of the adjusting worm 14 drives the first rotating column 9 to rotate through the meshing adjusting worm wheel 15, and the rotation of the first rotating column 9 drives the second rotating column 10 to rotate synchronously through the rotating disk 8, and the rotation of the first rotating column 9 and the second rotating column 10 is rotated through the corresponding threaded rod 12, and the threaded rod 12 drives the corresponding threaded displacement column 7 to move, so that the movement of the displacement column 7 drives the extension frame 2 to move, so that the extension frame 2 moves away from the fixed frame 1 to contact and extrude with the wall; When only a single extension frame 2 needs to be moved, the user can pull the moving plate 23 from the outside to drive the sliding sleeve 21 to slide horizontally on the outside of the second rotating column 10, so that the movement of the sliding sleeve 21 drives the compression spring 24 to compress and drives the two connecting rods 22 to move, and the connecting rod 22 drives the rotatably connected anti-slip block 20 to move inside the synchronous block 18 through the limit of the moving column 19, so that the anti-slip block 20 is separated from the slidably connected rotating disk 8, so that the rotation of the rotating disk 8 cannot drive the second rotating column 10 to rotate at the same time, and then the threaded rod 12 on the outside of the first rotating column 9 drives the corresponding extension frame 2 to move, so as to realize unilateral adjustment.

[0024] Embodiment 2 Reference Figure 2 and Figure 8 A device for reinforcing the bottom of a beam of a building structure, wherein fixed shells 3 are fixed at both ends of the top of a fixed frame 1, and reinforcing plates 4 are arranged on the tops of the two fixed shells 3, and a supporting mechanism is installed inside each fixed shell 3, and the supporting mechanism includes a transmission gear 25, a rotating gear 26, a connecting column 27, an extrusion rod 28 and a sliding block 29, and a transmission gear 25 is rotatably connected to the bottom end of one end of the fixed shell 3, and the transmission gear 25 is meshed and connected with the extension frame 2, so that the movement of the extension frame 2 drives the transmission gear 25 to rotate, and a toothed groove 6 is provided at the top of the extension frame 2 and at a position corresponding to the transmission gear 25, and the extension frame 2 is meshed and connected with the transmission gear 25 through the toothed groove 6, so that the movement of the extension frame 2 drives the transmission gear 25 to rotate through the toothed groove 6; A rotating gear 26 is meshed and connected to the top of the transmission gear 25 and is located inside the fixed shell 3. A connecting column 27 is fixed inside the rotating gear 26. The connecting column 27 is rotatably connected to the fixed shell 3, so that the rotating gear 26 rotates through the rotation of the transmission gear 25 under the support of the connecting column 27. An extrusion rod 28 is fixed to the outside of the connecting column 27 and located between the two rotating gears 26. The extrusion rod 28 is slidably connected to the fixed shell 3. A sliding block 29 is rotatably connected to the end of the extrusion rod 28 away from the connecting column 27. The sliding block 29 is slidably connected to the reinforcement plate 4, so that the rotation of the connecting column 27 drives the sliding block 29 to rotate and move through the extrusion rod 28, and the height of the reinforcement plate 4 is adjusted by the sliding connection between the sliding block 29 and the reinforcement plate 4.

[0025] The use process of the building structure beam bottom reinforcement device provided by the present invention is as follows: when the extension frames 2 at both ends of the fixed frame 1 move at the same time, the movement of the extension frame 2 drives the meshing transmission gear 25 to rotate through the toothed groove 6, so that the rotation of the transmission gear 25 drives the meshing rotation gear 26 to rotate, and the rotation gear 26 drives the connection column 27 to rotate, so that the rotation of the connection column 27 drives the extrusion rod 28 to rotate synchronously, and the rotation of the extrusion rod 28 drives the rotationally connected sliding block 29 to adjust its position by sliding inside the reinforcement plate 4, so that the reinforcement plate 4 is horizontally raised, and then the bottom of the building structure beam is supported; When the bottom of the building structure beam is inclined, the movable plate 23 is moved to disengage the anti-slip block 20 from the slidingly connected rotating disk 8, so that the rotation of the first rotating column 9 drives the corresponding threaded rod 12 to rotate independently, and the extension frame 2 outside the threaded rod 12 fixed to the first rotating column 9 is rotated to move independently through the threaded connection, so that the transmission gear 25 located inside the fixed shell 3 at the top of the first rotating column 9 rotates, and then the extrusion rod 28 at the top of the first rotating column 9 rotates, so that one end of the reinforcement plate 4 located at the top of the first rotating column 9 is tilted and raised, thereby supporting the inclined bottom of the building structure beam.

[0026] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the present invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A building structure beam bottom reinforcement device, characterized in that: The invention comprises a fixed frame (1), both ends of which are slidably connected to an extension frame (2), a transmission mechanism for driving the extension frame (2) to move is installed on the inner side of the fixed frame (1), the transmission mechanism comprising a rotating disk (8), a first rotating column (9), a second rotating column (10), a threaded rod (12), an adjustment drive motor (13), an adjustment worm (14) and an adjustment worm wheel (15), one end of the fixed frame (1) is internally rotatably connected to the first rotating column (9), the other end of the fixed frame (1) is internally rotatably connected to the second rotating column (10), the first rotating column (9) is close to the second rotating column (10), and the second rotating column (10) is close to the first rotating column (9). ) is fixed with a rotating disk (8) at one end, and a threaded rod (12) is fixed to each end of the first rotating column (9) and the second rotating column (10) which are away from each other, and a displacement column (7) is threadedly connected to the outer side of the end of the threaded rod (12) away from the rotating disk (8), and the displacement column (7) is fixed to the extension frame (2), and an adjustment drive motor (13) is fixed inside one end of the fixed frame (1), and an adjustment worm (14) is connected to the output end of the adjustment drive motor (13), and an adjustment worm gear (15) is meshedly connected to one side of the adjustment worm gear (14), and the inner side of the adjustment worm gear (15) is fixed to the first rotating column (9).

2. A building structure beam bottom reinforcement device according to claim 1, characterized in that: Four end corners at both ends of the fixed frame (1) are fixed with guide rods (5), and the fixed frame (1) and the extension frame (2) are slidably connected via the guide rods (5).

3. A building structure beam bottom reinforcement device according to claim 1, characterized in that: A synchronizing assembly for connecting to a rotating disk (8) is installed at one end of the second rotating column (10) close to the first rotating column (9), the synchronizing assembly comprising a synchronizing block (18), a moving column (19), an anti-dropping block (20), a sliding sleeve (21), a connecting rod (22), a moving plate (23) and a compression spring (24). A synchronizing block (18) is fixed to one end of the second rotating column (10) close to the first rotating column (9), the outer side of the synchronizing block (18) is slidably connected to the rotating disk (8), the inner sides of both sides of the synchronizing block (18) are slidably connected to the moving columns (19), and the outer sides of the moving columns (19) are fixed. An anti-slip block (20) is provided, the anti-slip block (20) is slidably connected to the rotating disk (8), a sliding sleeve (21) is slidably connected to the outer side of one end of the second rotating column (10) close to the synchronous block (18), connecting rods (22) are rotatably connected to both sides of the sliding sleeve (21), the connecting rods (22) are rotatably connected to the anti-slip block (20), a compression spring (24) is sleeved on the outer side of the second rotating column (10) and located at one end of the sliding sleeve (21) away from the synchronous block (18), a movable plate (23) is rotatably connected to the outer side of the sliding sleeve (21), and the movable plate (23) is slidably connected to the fixed frame (1).

4. A building structure beam bottom reinforcement device according to claim 3, characterized in that: An anti-slip groove (16) is provided at one end of the inner side of the rotating disk (8) close to the first rotating column (9), and the synchronous block (18) is slidably connected to the rotating disk (8) via the anti-slip groove (16).

5. A building structure beam bottom reinforcement device according to claim 3, characterized in that: Synchronous grooves (17) are evenly distributed on the inner side of the rotating disk (8) and at positions corresponding to the anti-slip blocks (20). The anti-slip blocks (20) are slidably connected to the rotating disk (8) via the synchronous grooves (17).

6. A building structure beam bottom reinforcement device according to claim 1, characterized in that: A fixing shell (3) is fixed to both ends of the top of the fixing frame (1), a reinforcing plate (4) is provided on the top of the two fixing shells (3), and a supporting mechanism is installed inside each fixing shell (3).

7. A building structure beam bottom reinforcement device according to claim 6, characterized in that: The support mechanism comprises a transmission gear (25), a rotating gear (26), a connecting column (27), an extrusion rod (28) and a sliding block (29); the bottom end of one end of the fixed shell (3) is rotatably connected to the transmission gear (25); the transmission gear (25) is meshingly connected to the extension frame (2); the top of the transmission gear (25) and located inside the fixed shell (3) is meshingly connected to the rotating gear (26); a connecting column (27) is fixed inside the rotating gear (26); the connecting column (27) is rotatably connected to the fixed shell (3); an extrusion rod (28) is fixed outside the connecting column (27) and located between the two rotating gears (26); the extrusion rod (28) is slidably connected to the fixed shell (3); the end of the extrusion rod (28) away from the connecting column (27) is rotatably connected to the sliding block (29); the sliding block (29) is slidably connected to the reinforcing plate (4).

8. A building structure beam bottom reinforcement device according to claim 7, characterized in that: A toothed groove (6) is provided at the top of the extension frame (2) and at a position corresponding to the transmission gear (25), and the extension frame (2) and the transmission gear (25) are meshedly connected via the toothed groove (6).

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