CN113530363B

CN113530363B - Electric power construction safety device

Info

Publication number: CN113530363B
Application number: CN202110732783.2A
Authority: CN
Inventors: 宋海涛; 王俊骄; 盛建峰; 王剑维; 范昌建; 李彦东; 刘育辰; 王汇凯; 李果; 孙韶阳
Original assignee: Qixia Power Supply Company State Grid Shandong Electric Power Co
Current assignee: Qixia Power Supply Company State Grid Shandong Electric Power Co
Priority date: 2021-06-30
Filing date: 2021-06-30
Publication date: 2023-05-16
Anticipated expiration: 2041-06-30
Also published as: CN113530363A

Abstract

The invention belongs to the field of safety protection, in particular to an electric power construction safety protection device, which aims at the problems that most of the existing electric power construction fences are fixed, inconvenient to store and move and inconvenient to carry, and the existing electric power construction fences are currently provided with a base, wherein first mounting grooves are formed in two sides of the base, connecting rods are slidably arranged in the two first mounting grooves, one ends of the two connecting rods are fixedly provided with fixing seats through welding, symmetrical two fixing blocks are fixedly arranged at the bottoms of the two fixing seats through welding, moving mechanisms are arranged at the bottoms of the four fixing blocks, and upright posts are fixedly arranged at the tops of the two fixing seats through welding.

Description

Electric power construction safety device

Technical Field

The invention relates to the technical field of safety protection, in particular to a safety protection device for electric power construction.

Background

At present, the number of electric power construction sites in society is increasing, and in order to ensure the safety of pedestrians and simultaneously provide a relatively quiet environment for electric power constructors, people start to use electric power construction fences. The electric power construction fence device is one of the technical measures for ensuring the safety of field workers, and the possibility of entering non-construction workers is greatly reduced.

Among the prior art, electric power construction rail is in the use, and is mostly fixed, is inconvenient for accomodate, and is inconvenient for remove to lead to inconvenient transport, for this reason we propose an electric power construction safety device and are used for solving above-mentioned problem.

Disclosure of Invention

The invention aims to solve the defects that in the prior art, most of electric construction fences are fixed, inconvenient to store and move in the using process, so that the electric construction fences are inconvenient to carry.

In order to achieve the above purpose, the present invention adopts the following technical scheme:

the utility model provides an electric power construction safety protection device, the on-line screen storage device comprises a base, first mounting groove has all been seted up to the both sides of base, equal slidable mounting has the connecting rod in two first mounting grooves, the one end of two connecting rods has the fixing base through welded fastening, two fixed blocks of symmetry have been all installed through welded fastening to the bottom of two fixing bases, the bottom of four fixed blocks all is provided with moving mechanism, the top of two fixing bases has the stand through welded fastening installation, the top of two stands has the fixed plate through welded fastening installation, the bottom of two fixed plates has first connecting block and second connecting block through welded fastening installation respectively, the mounting hole has been seted up on the second connecting block, install the bolt in the mounting hole rotation, threaded hole has been seted up on the first connecting block, the bolt cooperatees with the screw hole, the effect of two fixed plates can be played to the bolt, the two fixing plates are provided with a second mounting groove on one side adjacent to each other, the same slide plate is slidably mounted in the two second mounting grooves, two symmetrical pairs of first breast boards are fixedly mounted on one side adjacent to the two upright posts, the four first breast boards are provided with a third mounting groove, the four third mounting grooves are respectively and slidably provided with two second breast boards, the outer sides of the two second breast boards are fixedly provided with four limiting blocks through welding, the inner walls of the four third mounting grooves are provided with two symmetrical limiting grooves, the limiting blocks are slidably connected with the inner walls of the limiting grooves, when the four first breast boards horizontally move, eight limiting blocks can respectively and firmly play a role in stabilizing the movement of the two second breast boards, the two first through holes are provided with first through holes, the bottoms of the two fixing seats are respectively provided with a fourth mounting groove, the two fourth mounting grooves are respectively internally provided with fixing mechanisms, second spout has all been seted up to the both sides inner wall of two fourth mounting grooves, has all seted up two second empty slots of symmetry in two fixing bases, and the second through-hole has all been seted up to the inner wall in four second empty slots, and the second through-hole communicates with each other with the second spout, all rotates in four second through-holes and installs the second worm.

Preferably, the moving mechanism comprises four sliding blocks, four universal wheels, four second threaded rods and four second worm wheels, wherein first sliding grooves are formed in the bottoms of the four fixed blocks, the outer sides of the four sliding blocks are respectively connected with the inner walls of the four first sliding grooves in a sliding mode, the outer sides of the four universal wheels are respectively connected with the bottoms of the four sliding blocks in a rotating mode, third through holes are formed in the inner walls of the bottoms of the four second empty grooves, the four third through holes are respectively communicated with the four first sliding grooves, the outer sides of the four second threaded rods are respectively connected with the inner walls of the four third through holes in a sliding mode, second threaded grooves are formed in the tops of the four sliding blocks, the outer sides of the four second threaded rods are respectively connected with the inner walls of the four second threaded grooves in a threaded mode, the inner rings of the four second worm wheels are respectively connected with the outer sides of the four second threaded rods in a sliding mode, and the four second worm wheels are respectively meshed with the four second worm wheels.

Preferably, the expansion mechanism comprises two handles, two first worms and two rectangular rods, wherein first empty slots are formed in the two upright posts, fourth through holes are formed in the two upright posts, the two fourth through holes are respectively communicated with the two first empty slots, the outer sides of the two first worms are respectively in sliding connection with the inner walls of the two fourth through holes, the outer sides of the two handles are respectively in fixed connection with one ends of the two first worms through welding, the outer sides of the two handles are respectively in sliding connection with the two upright posts, rectangular slots are formed in the other ends of the two first worms, and the outer sides of the rectangular rods are in sliding connection with the inner walls of the two rectangular slots.

Preferably, the fixing mechanism comprises two anchor rods, two first threaded rods and two first worm gears, the inner walls of the tops of the two fourth mounting grooves are respectively provided with a fifth through hole, the two fifth through holes are respectively communicated with the two first empty grooves, the outer sides of the two first threaded rods are respectively in sliding connection with the inner walls of the two fifth through holes, the inner rings of the two first worm gears are respectively and fixedly connected with the outer sides of the two first threaded rods through welding, the two first worm gears are respectively meshed with the two first worm gears, the outer sides of the two anchor rods are respectively in sliding connection with the inner walls of the two fourth mounting grooves, the tops of the two anchor rods are respectively provided with a first thread groove, and the outer sides of the two first threaded rods are respectively in threaded connection with the inner walls of the two first thread grooves.

Preferably, the outer sides of the two anchor rods are fixedly provided with two symmetrical racks through welding, the outer sides of the two racks are respectively in sliding connection with the inner walls of the two second sliding grooves, one ends of the four second worms are fixedly provided with gears through welding, and the gears are meshed with the racks.

Preferably, bearings are fixedly mounted on the top inner walls of the two upright posts, the two first sliding grooves, the two second empty grooves and the two fourth mounting grooves respectively through welding, and the inner rings of the eight bearings are fixedly connected with the outer sides of the two first worms, the two second threaded rods, the two second worms and the two first threaded rods respectively through welding.

Compared with the prior art, the invention has the beneficial effects that:

1. this scheme is when promoting two handles and is close to each other, and two stands drive four first fence boards respectively and are close to each other, and two fixing bases drive two connecting rods respectively and are close to each other simultaneously to can reduce its horizontal occupation volume, conveniently carry.

2. This scheme is when rotating two handles, and two first worms drive two first worm wheel rotations respectively, and two first threaded rods drive two stock respectively and vertically move downwards, and when two stock vertical move downwards to certain position, two stock can fix two fixing bases respectively, improves its stability.

3. According to the scheme, when the two anchor rods vertically move upwards, the four racks respectively drive the four gears to rotate, the four second worms respectively drive the four second worm gears to rotate, and the four second threaded rods respectively drive the four sliding blocks and the four universal wheels to vertically move downwards, so that the four sliding blocks and the four universal wheels can conveniently move through the four universal wheels.

The portable storage rack can be conveniently stored or expanded in the use process, and is convenient to move, so that the portable storage rack can be conveniently carried, and is simple in structure and convenient to use.

Drawings

Fig. 1 is a schematic structural diagram of a safety protection device for electric power construction according to the present invention;

fig. 2 is a schematic diagram of a front view of a safety protection device for electric power construction according to the present invention;

fig. 3 is a schematic sectional structural view of a safety protection device for electric power construction according to the present invention;

fig. 4 is an enlarged schematic structural view of a portion a of fig. 2 of the safety protection device for electric power construction according to the present invention;

fig. 5 is an enlarged schematic diagram of a portion B of fig. 3 of the safety device for electric power construction according to the present invention.

In the figure: 1 base, 2 connecting rods, 3 fixing seats, 4 fixing blocks, 5 first sliding grooves, 6 sliding blocks, 7 universal wheels, 8 upright posts, 9 fixing plates, 10 sliding plates, 11 first breast plates, 12 second breast plates, 13 limit grooves, 14 limit blocks, 15 first connecting blocks, 16 second connecting blocks, 17 bolts, 18 handles, 19 first empty grooves, 20 first worms, 21 rectangular rods, 22 first worm gears, 23 first threaded rods, 24 anchor rods, 25 second sliding grooves, 26 racks, 27 gears, 28 second worms, 29 second empty grooves, 30 second threaded rods and 31 second worm gears.

Description of the embodiments

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

Example 1

Referring to fig. 1-5, an electric power construction safety protection device comprises a base 1, first mounting grooves are respectively formed in two sides of the base 1, connecting rods 2 are respectively and slidably mounted in the two first mounting grooves, one ends of the two connecting rods 2 are respectively and fixedly mounted with a fixed seat 3 through welding, symmetrical two fixed blocks 4 are respectively and fixedly mounted at the bottoms of the two fixed seats 3 through welding, moving mechanisms are respectively and fixedly mounted at the bottoms of the four fixed blocks 4, upright posts 8 are respectively and fixedly mounted at the tops of the two fixed seats 3, fixed plates 9 are respectively and fixedly mounted at the tops of the two upright posts 8 through welding, first connecting blocks 15 and second connecting blocks 16 are respectively and fixedly mounted at the bottoms of the two fixed plates 9, mounting holes are respectively formed in the second connecting blocks 16, bolts 17 are rotatably mounted in the mounting holes, threaded holes are formed in the first connecting blocks 15, the bolts 17 are matched with the threaded holes, the bolts 17 can play a role of fixing two fixing plates 9, the second mounting grooves are respectively formed in the adjacent sides of the two fixing plates 9, the same slide plate 10 is slidably mounted in the two second mounting grooves, two symmetrical pairs of first baffle plates 11 are respectively fixedly mounted on the adjacent sides of the two upright posts 8, third mounting grooves are respectively formed in the four first baffle plates 11, two second baffle plates 12 are respectively slidably mounted in the four third mounting grooves, four limiting blocks 14 are respectively fixedly mounted on the outer sides of the two second baffle plates 12 through welding, two symmetrical limiting grooves 13 are respectively formed in the inner walls of the four third mounting grooves, the limiting blocks 14 are slidably connected with the inner walls of the limiting grooves 13, when the four first baffle plates 11 horizontally move, the eight limiting blocks 14 can respectively play a role of stabilizing the movement of the two second baffle plates 12, the two upright posts 8 are respectively provided with first through holes, the extension mechanism is arranged in each of the two first through holes, the fourth mounting grooves are formed in the bottoms of the two fixing seats 3, the fixing mechanisms are arranged in each of the two fourth mounting grooves, the second sliding grooves 25 are formed in the inner walls of the two sides of each of the two fourth mounting grooves, the symmetrical two second empty grooves 29 are formed in each of the two fixing seats 3, the second through holes are formed in the inner walls of the four second empty grooves 29, the second through holes are communicated with the second sliding grooves 25, and the second worm 28 is rotatably arranged in each of the four second through holes.

In this embodiment, the moving mechanism includes four sliders 6, four universal wheels 7, four second threaded rods 30 and four second worm gears 31, the bottoms of the four fixed blocks 4 are all provided with first sliding grooves 5, the outer sides of the four sliders 6 are respectively in sliding connection with the inner walls of the four first sliding grooves 5, the outer sides of the four universal wheels 7 are respectively in rotating connection with the bottoms of the four sliders 6, third through holes are respectively formed in the inner walls of the bottoms of the four second empty grooves 29, the four third through holes are respectively communicated with the four first sliding grooves 5, the outer sides of the four second threaded rods 30 are respectively in sliding connection with the inner walls of the four third through holes, second threaded grooves are respectively formed in the tops of the four sliders 6, the outer sides of the four second threaded rods 30 are respectively in threaded connection with the inner walls of the four second threaded grooves, the inner rings of the four second worm gears 31 are respectively in fixed connection with the outer sides of the four second threaded rods 30 through welding, the four second threaded rods 31 are respectively meshed with the four second worm gears 28, and when the four second worm gears 28 rotate, the four second worm gears 31 can respectively drive the four second threaded rods 30 to rotate.

In this embodiment, the expanding mechanism includes two handles 18, two first worms 20 and two rectangular rods 21, first empty slots 19 have all been seted up in two stand 8, fourth through holes have all been seted up to two stand 8, two fourth through holes communicate with each other with two first empty slots 19 respectively, the outside of two first worms 20 respectively with the inner wall sliding connection of two fourth through holes, the outside of two handles 18 respectively with the one end of two first worms 20 through welded fastening connection, the outside of two handles 18 respectively with two stand 8 sliding connection, rectangular slots have all been seted up to the other end of two first worms 20, the outside of rectangular rods 21 and the inner wall sliding connection of two rectangular slots, when pulling two handle 18 horizontal migration, two stand 8 can drive two first worms 20 horizontal migration respectively, the outside of rectangular rods 21 is through welded fastening connection with two montants of symmetry respectively with the outside fixed connection of two second breast boards 12.

In this embodiment, the fixing mechanism includes two anchor rods 24, two first threaded rods 23 and two first worm gears 22, the top inner walls of the two fourth installation grooves are all provided with fifth through holes, the two fifth through holes are respectively communicated with the two first empty grooves 19, the outer sides of the two first threaded rods 23 are respectively in sliding connection with the inner walls of the two fifth through holes, the inner rings of the two first worm gears 22 are respectively and fixedly connected with the outer sides of the two first threaded rods 23 through welding, the two first worm gears 22 are respectively meshed with the two first worms 20, the outer sides of the two anchor rods 24 are respectively and slidably connected with the inner walls of the two fourth installation grooves, the tops of the two anchor rods 24 are respectively provided with first threaded grooves, the outer sides of the two first threaded rods 23 are respectively in threaded connection with the inner walls of the two first threaded grooves, and when the two first worms 20 rotate, the two first worm gears 22 can respectively drive the two first threaded rods 23 to rotate.

In this embodiment, two symmetrical racks 26 are fixedly mounted on the outer sides of the two anchor rods 24 through welding, the outer sides of the two racks 26 are respectively and slidably connected with the inner walls of the two second sliding grooves 25, gears 27 are fixedly mounted on one ends of four second worms 28 through welding, the gears 27 are meshed with the racks 26, and when the two anchor rods 24 move vertically, the four racks 26 can respectively drive the four gears 27 to rotate.

In this embodiment, bearings are fixedly mounted on the top inner walls of the two upright posts 8, the two first sliding grooves 5, the two second empty grooves 29 and the two fourth mounting grooves respectively through welding, the inner rings of the eight bearings are fixedly connected with the outer sides of the two first worms 20, the two second threaded rods 30, the two second worms 28 and the two first threaded rods 23 respectively through welding, and when the two first worms 20, the two second threaded rods 30, the two second worms 28 and the two first threaded rods 23 rotate, the eight bearings can play a role in stabilizing the rotation of the two first worms 20, the two second threaded rods 30, the two second worms 28 and the two first threaded rods 23 respectively.

The working principle is that when in use, the bolt 17 can be rotated, the bolt 17 and the threaded hole are matched, the fixing of the fixed plate 9 can be released by the bolt 17, then the two handles 18 are pulled to be away from each other, the two handles 18 respectively drive the two upright posts 8 to be away from each other, the two upright posts 8 respectively drive the four first breast boards 11, the two fixed plates 9 and the two connecting rods 2 to be away from each other, the use area can be enlarged, then the two handles 18 are rotated, the two handles 18 respectively drive the two first worms 20 to rotate, the two first worms 20 respectively drive the two first worm wheels 22 to rotate, the two first worm wheels 22 respectively drive the two first threaded rods 23 to rotate, the two first threaded rods 23 respectively drive the two anchor rods 24 to vertically move downwards, when the two anchor rods 24 vertically move to a certain position, the two anchor rods 24 can respectively fix the two fixed seats 3, simultaneously, the two anchor rods 24 respectively drive the four racks 26 to vertically move downwards, the four racks 26 respectively drive the four gears 27 to rotate, the four gears 27 respectively drive the four second worms 28 to rotate, the four second worms 28 respectively drive the four second worm gears 31 to rotate, the four second worm gears 31 respectively drive the second threaded rods 30 to rotate, the four second threaded rods 30 respectively drive the four sliding blocks 6 and the four universal wheels 7 to vertically move upwards, when the four universal wheels 7 move to a certain position, the two fixing seats 3 are in contact with the ground, so that the stability of the two anchor rods can be improved, when the use is finished, the two first worm gears 20 are respectively driven to rotate by reversing the two handles 18, the two first worm gears 20 respectively drive the two first worm gears 22 to rotate, the two first worm gears 22 respectively drive the two first threaded rods 23 to rotate, the two first threaded rods 23 drive the two anchor rods 24 to vertically move upwards respectively, when the two anchor rods 24 vertically move to a certain position, thereby the two anchor rods 24 can respectively release the fixation of the two fixing seats 3, simultaneously the two anchor rods 24 respectively drive the four racks 26 to vertically move upwards, the four racks 26 respectively drive the four gears 27 to rotate, the four gears 27 respectively drive the four second worms 28 to rotate, the four second worms 28 respectively drive the four second worm wheels 31 to rotate, the four second worm wheels 31 respectively drive the second threaded rods 30 to rotate, the four second threaded rods 30 respectively drive the four sliding blocks 6 and the four universal wheels 7 to vertically move downwards, the four universal wheels 7 can be conveniently moved, then the two handles 18 are pushed to mutually approach, the two upright posts 8 are respectively driven to mutually approach, the two upright posts 8 respectively drive the four first breast plates 11, the two fixing plates 9 and the two connecting rods 2 to mutually approach, further the transverse occupied volumes of the two fixing plates can be reduced, the four first breast plates are conveniently carried, and then the fixing plates 9 can be fixed by setting the bolts 17 and the threaded holes to mutually match.

Example two

In this embodiment, the expansion mechanism includes two handles 18, two first worms 20 and two rectangular rods 21, first empty slots 19 are all provided in the two upright posts 8, fourth through holes are all provided in the outer sides of the two upright posts 8, the two fourth through holes are respectively communicated with the two first empty slots 19, the outer sides of the two first worms 20 are respectively in sliding connection with the inner walls of the two fourth through holes, the outer sides of the two handles 18 are respectively in fixed connection with one ends of the two first worms 20 through welding, the outer sides of the two handles 18 are respectively in sliding connection with the outer sides of the two upright posts 8, rectangular slots are provided in the other ends of the two first worms 20, the outer sides of the rectangular rods 21 are in sliding connection with the inner walls of the two rectangular slots, when the two handles 18 are pulled to move horizontally, the two upright posts 8 can respectively drive the two first worms 20 to move horizontally, the outer sides of the rectangular rods 21 are respectively in fixed connection with two symmetrical upright posts through welding, and one ends of the two upright posts are respectively in fixed connection with the outer sides of the two second breast boards 12;

the working principle is that when in use, the bolt 17 can be rotated, the bolt 17 and the threaded hole are matched, the bolt 17 can be used for releasing the fixation of the fixed plate 9, then the two handles 18 are pulled to be away from each other, the two handles 18 respectively drive the two upright posts 8 to be away from each other, the two upright posts 8 respectively drive the four first breast boards 11, the two fixed plates 9 and the two connecting rods 2 to be away from each other, when the two first worms 20 are away from each other, the two upright posts can stabilize the rectangular rod 21, the rectangular rod 21 is prevented from falling off and expanding the use area, then the two handles 18 are rotated, the two handles 18 respectively drive the two first worms 20 to rotate, the two first worms 20 respectively drive the two first worm gears 22 to rotate, the two first worm gears 22 respectively drive the two first threaded rods 23 to rotate, the two first threaded rods 23 respectively drive the two anchor rods 24 to vertically move downwards, when the two anchor rods 24 move vertically to a certain position, the two anchor rods 24 can respectively fix the two fixing seats 3, meanwhile, the two anchor rods 24 respectively drive the four racks 26 to move vertically downwards, the four racks 26 respectively drive the four gears 27 to rotate, the four gears 27 respectively drive the four second worms 28 to rotate, the four second worms 28 respectively drive the four second worm gears 31 to rotate, the four second worm gears 31 respectively drive the second threaded rods 30 to rotate, the four second threaded rods 30 respectively drive the four sliding blocks 6 and the four universal wheels 7 to move vertically upwards, when the four universal wheels 7 move to a certain position, the two fixing seats 3 are in contact with the ground, so that the stability of the two anchor rods can be improved, when the use is finished, the two handles 18 can be reversed, the two handles 18 respectively drive the two first worms 20 to rotate, the two first worm screws 20 respectively drive the two first worm gears 22 to rotate, the two first worm gears 22 respectively drive the two first threaded rods 23 to rotate, the two first threaded rods 23 respectively drive the two anchor rods 24 to vertically move upwards, when the two anchor rods 24 vertically move to a certain position, thereby the two anchor rods 24 can respectively release fixation of the two fixing seats 3, simultaneously the two anchor rods 24 respectively drive the four racks 26 to vertically move upwards, the four racks 26 respectively drive the four gears 27 to rotate, the four gears 27 respectively drive the four second worm screws 28 to rotate, the four second worm screws 28 respectively drive the four second worm gears 31 to rotate, the four second worm gears 31 respectively drive the second threaded rods 30 to rotate, the four second threaded rods 30 respectively drive the four sliding blocks 6 and the four universal wheels 7 to vertically move downwards, the two handles 18 can be conveniently moved through the four universal wheels 7, the two handles 18 respectively drive the two stand columns 8 to mutually approach, the two stand columns 8 respectively drive the four first breast plates 11, the two fixing plates 9 and the two connecting rods 2 to mutually approach each other, the four second breast plates can be conveniently moved, the four breast plates and the screw bolts can be conveniently moved through the screw bolts 17 to be fixed by the screw bolts 17.

Claims

1. The utility model provides an electric power construction safety device, includes base (1), its characterized in that, first mounting groove has all been seted up to the both sides of base (1), equal slidable mounting has connecting rod (2) in two first mounting grooves, the equal fixed mounting of one end of two connecting rods (2) has fixing base (3), two fixed blocks (4) of equal fixed mounting of bottom of two fixing bases (3), the bottom of four fixed blocks (4) all is provided with moving mechanism, the equal fixed mounting in top of two fixing bases (3) has stand (8), the equal fixed mounting in top of two stand (8) has fixed plate (9), the second mounting groove has all been seted up to adjacent one side of two fixed plates (9), sliding mounting has same slide (10) in two second mounting grooves, two pairs of first hurdle plates (11) of equal fixed mounting of adjacent one side of two stand (8), all set up third mounting groove on four first hurdle plates (11), sliding mounting has two second hurdle plates (12) in four third mounting grooves, two equal fixed mounting groove (8) have two inner wall (25) of two equal inner walls of two stand (8), two inner wall (3) have all been seted up in two first inner wall (25), the inner walls of the four second empty slots (29) are respectively provided with a second through hole, the second through holes are communicated with the second sliding slots (25), and second worms (28) are respectively and rotatably arranged in the four second through holes;

the moving mechanism comprises four sliding blocks (6), four universal wheels (7), four second threaded rods (30) and four second worm wheels (31), wherein the bottoms of the four fixed blocks (4) are provided with first sliding grooves (5), the outer sides of the four sliding blocks (6) are respectively in sliding connection with the inner walls of the four first sliding grooves (5), the outer sides of the four universal wheels (7) are respectively in rotating connection with the bottoms of the four sliding blocks (6), the inner walls of the bottoms of the four second empty grooves (29) are provided with third through holes, the four third through holes are respectively communicated with the four first sliding grooves (5), the outer sides of the four second threaded rods (30) are respectively in sliding connection with the inner walls of the four third through holes, the tops of the four sliding blocks (6) are respectively provided with second threaded grooves, the outer sides of the four second threaded rods (30) are respectively in threaded connection with the inner walls of the four second threaded grooves, the inner rings of the four second threaded rods (31) are respectively fixedly connected with the outer sides of the four second worm wheels (30), and the four second worm wheels (31) are respectively meshed with the four second worm wheels (28);

the expansion mechanism comprises two handles (18), two first worms (20) and two rectangular rods (21), wherein first empty slots (19) are formed in the two upright posts (8), fourth through holes are formed in the two upright posts (8), the two fourth through holes are respectively communicated with the two first empty slots (19), the outer sides of the two first worms (20) are respectively and slidably connected with the inner walls of the two fourth through holes, the outer sides of the two handles (18) are respectively and fixedly connected with one ends of the two first worms (20), the outer sides of the two handles (18) are respectively and slidably connected with the two upright posts (8), rectangular slots are formed in the other ends of the two first worms (20), and the outer sides of the rectangular rods (21) are slidably connected with the inner walls of the two rectangular slots;

the fixing mechanism comprises two anchor rods (24), two first threaded rods (23) and two first worm gears (22), wherein fifth through holes are formed in the inner walls of the tops of the two fourth mounting grooves, the two fifth through holes are respectively communicated with the two first empty grooves (19), the outer sides of the two first threaded rods (23) are respectively and slidably connected with the inner walls of the two fifth through holes, the inner rings of the two first worm gears (22) are respectively and fixedly connected with the outer sides of the two first threaded rods (23), the two first worm gears (22) are respectively meshed with the two first worms (20), the outer sides of the two anchor rods (24) are respectively and slidably connected with the inner walls of the two fourth mounting grooves, first threaded grooves are formed in the tops of the two anchor rods (24), and the outer sides of the two first threaded rods (23) are respectively and slidably connected with the inner walls of the two first threaded grooves;

two symmetrical racks (26) are fixedly arranged on the outer sides of the two anchor rods (24), the outer sides of the two racks (26) are respectively connected with the inner walls of the two second sliding grooves (25) in a sliding mode, gears (27) are fixedly arranged at one ends of the four second worms (28), and the gears (27) are meshed with the racks (26);

four limiting blocks (14) are fixedly arranged on the outer sides of the two second breast boards (12), two symmetrical limiting grooves (13) are formed in the inner walls of the four third mounting grooves, and the limiting blocks (14) are in sliding connection with the inner walls of the limiting grooves (13);

the bottoms of the two fixing plates (9) are respectively and fixedly provided with a first connecting block (15) and a second connecting block (16), the second connecting block (16) is provided with a mounting hole, a bolt (17) is rotatably arranged in the mounting hole, the first connecting block (15) is provided with a threaded hole, and the bolt (17) is matched with the threaded hole;

bearings are fixedly arranged on the top inner walls of the two upright posts (8), the two first sliding grooves (5), the two second empty grooves (29) and the two fourth installation grooves, and inner rings of the eight bearings are fixedly connected with the outer sides of the two first worms (20), the two second threaded rods (30), the two second worms (28) and the two first threaded rods (23) respectively.