CN110778087B

CN110778087B - Lifting scaffold with anti-falling function

Info

Publication number: CN110778087B
Application number: CN201911118238.3A
Authority: CN
Inventors: 卜建荣; 徐君燕
Original assignee: Zhejiang Industry Polytechnic College
Current assignee: HANGZHOU XINGWAIXING TECHNOLOGY CO.,LTD.
Priority date: 2019-11-15
Filing date: 2019-11-15
Publication date: 2021-05-28
Anticipated expiration: 2039-11-15
Also published as: CN110778087A

Abstract

The invention discloses a lifting scaffold with an anti-falling function, which comprises two groups of supporting frames, supporting plates and connecting blocks, wherein the supporting frames are arranged above the supporting frames, the supporting plates are arranged at the upper parts of the supporting frames, foot supporting units and walking units are respectively arranged at the outer sides and the inner sides of the lower parts of the supporting frames, a plurality of lug plates are connected to the left and right sides of the connecting blocks, reinforcing beams are arranged at the inner sides of the supporting frames, one ends, far away from the connecting blocks, of the lug plates are fixedly connected with the reinforcing beams, the supporting frames comprise two vertical beams, and a plurality of cross beams are connected between the two vertical beams. The scaffold provided by the invention has an anti-falling structure, has a double-protection effect, and solves the problem that the safety coefficient of the anti-falling device in the prior art is not high.

Description

Lifting scaffold with anti-falling function

Technical Field

The invention relates to the technical field of auxiliary tools for buildings, in particular to a lifting scaffold with an anti-falling function.

Background

The scaffold is various supports which are erected for workers to operate and solve vertical and horizontal transportation on a construction site, is usually applied to places which cannot be directly constructed on an outer wall, interior decoration or a high floor height on a construction site, and is mainly used for up-and-down operation of constructors or enclosure of a peripheral safety net, high-altitude installation components and the like. The lifting scaffold is suspended at the lower part after rising, so that the falling danger is caused. For safety reasons, the lifting scaffold must then be fitted with a safety brake.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a lifting scaffold with an anti-falling function.

In order to achieve the purpose, the invention provides the following technical scheme to realize the purpose:

a lifting scaffold with an anti-falling function comprises a support frame, support frames, support plates and connecting blocks, wherein the support frame is provided with two groups, the support frames are arranged above the support frame, the support plates are arranged on the upper portion of the support frame, foot supporting units are arranged on the outer side of the lower portion of the support frame, a plurality of reinforcing beams are connected to the left side and the right side of each connecting block, ear plates are arranged on the inner sides of the support frames, one ends, away from the connecting blocks, of the reinforcing beams are fixedly connected with the ear plates, the support frame comprises two vertical beams, a plurality of cross beams are connected between the two vertical beams, four support rods are connected to the lower portion of the support frame, the lower portions of the four support rods are respectively inserted into the vertical beams, racks are arranged on the front sides of the support rods, a lifting motor frame is arranged, the middle part of the gear shaft is provided with a gear, the vertical beam is provided with an opening, the gear penetrates through the opening on the vertical beam to be meshed with the rack, a moving block is arranged in the supporting frame in a sliding manner, the right side of the supporting frame is provided with a lead screw motor seat, the upper part of the lead screw motor seat is provided with a lead screw motor, the moving block is provided with a threaded hole along the length direction of the supporting frame, a lead screw is arranged in the threaded hole, one end of the lead screw is connected with an output shaft of the lead screw motor, the upper part of the moving block is connected with a supporting plate, the upper part of the supporting plate is provided with a circle of guardrails, the foot supporting unit comprises a mounting plate fixed on the vertical beam, the front side of the mounting plate is sequentially provided with a first rotating seat, a second rotating seat and a third rotating seat from top to bottom, rotating shafts are rotatably arranged on, the foot supporting plate is connected between the first reinforcing plate and the second reinforcing plate, a shock absorption block is arranged at the lower part of the foot supporting plate, clamping holes are formed in the foot supporting plate, a first clamping block and a second clamping block are respectively arranged at the positions, located on the left side and the right side of the rotating shaft, of the front side of the mounting plate, clamping grooves are formed in the first clamping block and the second clamping block, the height of each clamping groove in the first clamping block is higher than that of each clamping groove in the second clamping block, a spring is sleeved on the rotating shaft and located between the second rotating seat and the first reinforcing plate, and when the foot supporting plate rotates by taking the rotating shaft as a shaft, the clamping holes can be clamped into the clamping grooves of the first clamping block or the second clamping block for fixation; the anti-falling mechanism is arranged on the vertical beam and comprises a supporting shell, the supporting shell is fixed on one side, opposite to the gear, of the vertical beam, the cross section of the supporting shell is U-shaped, a first fixing shaft and a second fixing shaft are fixedly connected in the supporting shell, the first fixing shaft is positioned above the second fixing shaft, a first sleeve is sleeved on the first fixing shaft, a mandril is fixed on the first sleeve, the lower portion of the mandril is connected with a first tension spring, a fixing seat is fixed on the right side wall of the supporting shell and is L-shaped, one end, far away from the mandril, of the first tension spring is connected with a horizontal section of the fixing seat, a first stop block is arranged at a position below the first sleeve in the supporting shell, a second sleeve is sleeved on the second fixing shaft, a brake block is fixed on the second sleeve, and two connecting plates are fixedly connected at positions, lower portion of the brake block, on the second sleeve, an activating block is rotatably arranged between the two connecting plates, and a second stop block is arranged at the position below the second sleeve in the supporting shell.

As preferred, the blind hole has been seted up on brake pads upper portion, be equipped with the movable block in the blind hole, the spacing groove has been seted up to the position that lies in the spacing groove both sides in the brake block, the movable block left and right sides all is connected with the pterygoid lamina, the pterygoid lamina slides and sets up at the spacing inslot, be connected with reset spring between movable block bottom and the blind hole bottom, the blind hole bottom is equipped with micro-gap switch, the movable block bottom is equipped with the lug, micro-gap switch's contact position is corresponding with lug central point, it has the telescopic pump to articulate between ejector pin and the support shell, micro-gap switch and.

As preferred, support frame lower part inboard is equipped with the walking unit, the walking unit includes the slider, the slider front side is connected with the link, the link sub-unit connection has the tie-beam, the tie-beam lower part is rotated and is provided with two and removes the wheel seat, it is provided with the removal wheel to rotate in the removal wheel seat, the embedded groove has been seted up on the perpendicular roof beam, the embedded groove sub-unit connection has the spout, the slider passes embedded groove card and goes into in erecting the roof beam, the link can remove along the spout, erect the position that is located the spout left and right sides on the roof beam and seted up two regulation holes, two the vertical setting of regulation hole is just parallel to each other, it has fixing bolt to twist on the regulation hole, be equipped with the fixed orifices on the slider, the fixing bolt front end passes behind the fixed orifices on the slider.

Preferably, two guide grooves are formed in the supporting frame along the length direction, a plurality of rollers are arranged on the lower portion of the supporting plate, and the lower portions of the rollers are located in the guide grooves.

Compared with the prior art, the invention has the beneficial effects that: the anti-falling mechanism is used for supporting the supporting rod when the lifting scaffold falls, and a double anti-falling design is adopted, so that the falling accident of the lifting scaffold when one anti-falling device fails is prevented; be provided with the heel brace unit, can open when the ground unevenness and use, the heel brace can stride across the regional and the subaerial smooth regional contact of subaerial unevenness, makes the bottom of scaffold keep the parallel and level everywhere, guarantees the stability when scaffold uses.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is an enlarged schematic view at A in FIG. 1;

FIG. 3 is a schematic structural view of the fall arrest mechanism of the present invention;

FIG. 4 is an enlarged schematic view at B of FIG. 3;

FIG. 5 is an enlarged schematic view at C of FIG. 3;

FIG. 6 is a schematic view of the brake pad of the present invention;

FIG. 7 is a side view of the present invention at the support stand;

FIG. 8 is a schematic structural view of a walking unit according to the present invention;

FIG. 9 is a schematic structural view of a foot supporting unit according to the present invention;

FIG. 10 is a top view of the support frame of the present invention;

fig. 11 is a top view of the present invention.

Reference numerals: 1. a support frame; 2. a support frame; 3. a support plate; 4. a guardrail; 5. a roller; 6. a traveling unit; 7. a foot support unit; 8. connecting blocks; 9. an ear plate; 10. a reinforcing beam; 11. a guide groove; 12. a moving block; 13. a screw rod; 14. a screw motor base; 15. a screw motor; 16. erecting a beam; 17. a cross beam; 18. a support bar; 19. a rack; 20. a lifting motor frame; 21. a lifting motor; 22. a gear shaft; 23. a gear; 24. an anti-falling mechanism; 25. a support housing; 26. a first fixed shaft; 27. a first sleeve; 28. a top rod; 29. a first tension spring; 30. a fixed seat; 31. a second fixed shaft; 32. a second sleeve; 33. anti-falling teeth; 34. a clamping hole; 35. a groove is embedded; 36. a chute; 37. an adjustment hole; 38. a slider; 39. a connecting frame; 40. a connecting beam; 41. moving the wheel seat; 42. a moving wheel; 43. fixing the bolt; 44. mounting a plate; 45. a first rotating base; 46. a second rotating base; 47. a third rotating base; 48. a rotating shaft; 49. a first clamping block; 50. a second clamping block; 51. a clamping groove; 52. a first reinforcing plate; 53. a second reinforcing plate; 54. a foot supporting plate; 55. a damper block; 56. a spring; 57. a brake pad; 58. a second tension spring; 59. a connecting plate; 60. activating a block; 61. a second stopper; 62. a first hinge mount; 63. a telescopic pump; 64. a second hinge mount; 65. blind holes; 66. a movable block; 67. a limiting groove; 68. a wing plate; 69. a return spring; 70. a bump; 71. a micro switch.

Detailed Description

The lifting scaffold with the anti-falling function of the invention will be further described with reference to the attached drawings 1-11.

The utility model provides a lifting scaffold who prevents weighing down function in area, including support frame 1, carriage 2, support frame 1 is provided with two, support frame 1 comprises two perpendicular roof beams 16 and a plurality of crossbeams 17 of connection between two perpendicular roof beams 16, carriage 2 is the rectangle frame construction that four roof beams welded, the inboard of two roof beams around carriage 2 is seted up flutedly, it is provided with movable block 12 to slide in the recess, movable block 12 sets up threaded hole along the recess direction, install lead screw 13 in the screw hole, the one end of lead screw 13 links to each other with the output shaft of lead screw motor 15 is fixed, lead screw motor 15 is fixed through lead screw motor cabinet 14 of connection on support frame 2. The upper part of the moving block 12 is fixed with a support plate 3, and the upper part of the support plate 3 is provided with a circle of guardrails 4. The screw motor 15 drives the screw 13 to rotate, so that the moving block 12 moves along the groove, and the supporting plate 3 is driven to move on the supporting frame 2 and is adjusted along with the construction position of a worker. Two guide ways 11 have been seted up along length direction on the carriage 2, and 3 lower parts of backup pad are equipped with a plurality of

gyro wheels

5, and 5 lower parts of gyro wheel are located guide way 11, and guide way 11 plays guide roller 5's effect, makes backup pad 3 remove and more steady on the assigned direction.

The guardrail 4 can be provided with a door for the staff to get in and out, so that the staff can conveniently get in or leave the support plate 3.

The 2 sub-unit connection of carriage has four bracing pieces 18, the lower part of bracing piece 18 is inserted in erecting the roof beam 16, the bracing piece 18 front side is equipped with rack 19, erect the roof beam 16 outside and be equipped with elevator motor frame 20, elevator motor frame 20 upper portion is equipped with elevator motor 21, be connected with gear shaft 22 on elevator motor 21's the output shaft, gear shaft 22 middle part is equipped with gear 23, be equipped with the opening on erecting the roof beam 16, gear 23 passes opening and rack 19 meshing on erecting the roof beam 16, elevator motor 21's output shaft drive gear 23 rotates, gear 23 removes at drive meshing's rack 19, thereby drive bracing piece 18 and remove in erecting the roof beam 16, play the effect of adjusting the 2 heights of carriage.

The foot supporting unit 7 comprises a mounting plate 44 fixed on the vertical beam 16, a first rotating seat 45, a second rotating seat 46 and a third rotating seat 47 are sequentially arranged on the front side of the mounting plate 44 from top to bottom, a rotating shaft 48 is rotatably arranged on the first rotating seat 45, the second rotating seat 46 and the third rotating seat 47, a first reinforcing plate 52 and a second reinforcing plate 53 are respectively fixed on the upper portion and the lower portion of the rotating shaft 48, a foot supporting plate 54 is connected between the first reinforcing plate 52 and the second reinforcing plate 53, a shock absorption block 55 is arranged on the lower portion of the foot supporting plate 54, a clamping hole 34 is arranged on the foot supporting plate 54, a first clamping block 49 and a second clamping block 50 are respectively arranged on the left side and the right side of the rotating shaft 48 on the front side of the mounting plate 44, clamping grooves 51 are respectively arranged on the first clamping block 49 and the second clamping block 50, the clamping grooves 51 on the first clamping block 49 are higher than the clamping grooves 51 on the second clamping block 50, a spring 56 is sleeved on the rotating, the spring 56 is located between the second rotating seat 46 and the first reinforcing plate 52. When the foot supporting unit 7 is used, the foot supporting plate 54 is rotated to one side of the second clamping block 50, the second clamping block 50 penetrates through the clamping hole 34 to clamp the clamping hole 34 into the clamping groove 51 on the second clamping block 50, and the bottom of the damping block 55 is in contact with the ground to play a supporting role; when the foot supporting unit 7 is not used, the foot supporting plate 54 is rotated to one side of the first clamping block 49, and since the clamping groove 51 on the first clamping block 49 is formed with a higher height, when the clamping hole 34 is clamped in the clamping groove 51 on the first clamping block 49, the spring 56 pushes the first reinforcing plate 52 upwards, and at this time, the bottom of the shock absorption block 55 is at a certain distance from the ground.

The walking unit 6 comprises a sliding block 38, a connecting frame 39 is connected to the front side of the sliding block 38, a connecting beam 40 is connected to the lower portion of the connecting frame 39, two movable wheel seats 41 are rotatably arranged on the lower portion of the connecting beam 40, movable wheels 42 are rotatably arranged in the movable wheel seats 41, embedded grooves 35 are formed in the vertical beam 16, sliding grooves 36 are connected to the lower portions of the embedded grooves 35, the sliding block 38 is inserted into the embedded grooves 35 and then moves downwards, the connecting frame 39 is clamped into the sliding grooves 36 and moves along the length direction of the sliding grooves 36, two adjusting holes 37 are formed in the positions, located on the left side and the right side of the sliding grooves 36, of the front side of the vertical beam 16, the two adjusting holes 37 are vertically arranged and parallel to each other, fixing bolts 43 are screwed into the adjusting holes 37, fixing holes are formed in the sliding block 38, the front ends of the fixing bolts 43 are abutted to the inner walls of the vertical, to select the use or non-use of the walking unit 6.

The anti-falling mechanism comprises a supporting shell 25 fixed on the rear side of a vertical beam 16, the cross section of the supporting shell 25 is U-shaped, a first fixing shaft 26 and a second fixing shaft 31 are fixedly connected in the supporting shell 25, the first fixing shaft 26 is positioned above the second fixing shaft 31, a first sleeve 27 is sleeved on the first fixing shaft 26, a mandril 28 is fixed on the first sleeve 27, a first tension spring 29 is connected to the lower portion of the mandril 28, a fixing seat 30 is fixed on the right side wall of the supporting shell 25, the fixing seat 30 is L-shaped, one end of the first tension spring 29, which is far away from the mandril 28, is connected with the horizontal section of the fixing seat 30, a first stop block is arranged at the position below the first sleeve 27 in the supporting shell 25, two second sleeves 32 are sleeved on the second fixing shaft 31, a brake block 57 is fixed on the second sleeve 32, two connecting plates 59 are fixedly connected at the position below the brake block 57 on the second, a second stopper 61 is provided in the support case 25 at a position below the second sleeve 32.

Ejector pin 28 includes bushing portion and ejector pin, bushing portion and the coaxial sliding connection of ejector pin, and threaded connection has two nut structures on the ejector pin, and two nut structures offset with bushing portion's tip. The length of the ejection part of the ejection rod is adjusted through a double-nut structure.

The activating block 60 is provided with a limiting part with a rounded upper part and a right-angle lower part at one end close to the second sleeve 32; through the rounding and the arrangement of the limiting part, when one end of the activating block 60, which is far away from the connecting plate 59, rotates upwards, the activating block 60 and the connecting plate 59 rotate relatively, so that the activating block 60 is kept in a vertical state, namely the activating block 60 is in an unexcited state, and the anti-falling teeth 33 cannot contact with the activating block 60 when moving downwards; when the limiting part abuts against the second sleeve 32, the activating block 60 is in a horizontal state, when the anti-falling teeth 33 move downwards to contact with the activating block 60, and the activating block 60 is driven to rotate downwards from the horizontal state, because the limiting part abuts against the second sleeve 32, the activating block 60 drives the connecting plate 59 and the second sleeve 32 to rotate together, so that the upper end of the brake block 57 moves towards the direction close to the anti-falling teeth 33, the brake block 57 stops abutting against the second stop block 61, and at the moment, the brake block 57 can be clamped into the lower part of the anti-falling teeth 33 to be supported. The end of the activating block 60 away from the connecting plate 59 is a trigger end, and the end surface of the trigger end is a circular arc surface.

The mandril 28 supports the anti-falling teeth 33 under the action of the first tension spring 29 to prevent falling for a first layer; when the first tension spring 29 is damaged and cannot pull the mandril 28 to a specified position, so that the supporting rod 18 falls down, the anti-falling teeth 33 move downwards to contact with the activating block 60, the activating block 60 is driven to rotate, the limiting part of the activating block 60 abuts against the second sleeve 32, the connecting plate 59 and the second sleeve 32 are driven to rotate together, the upper end of the brake block 57 moves towards the direction close to the anti-falling teeth 33, the stop is realized when the connecting plate 59 abuts against the second stop block 61, the brake block 57 can be clamped into the lower part of the anti-falling teeth 33 to be supported, the anti-falling effect is realized on the second layer, the two layers of anti-falling combined action is realized, and the safety of the scaffold.

Blind hole 65 has been seted up on brake pad 57 upper portion, be equipped with movable block 66 in the blind hole 65, spacing groove 67 has been seted up to the position that lies in spacing groove 67 both sides in brake pad 57, the movable block 66 left and right sides all is connected with pterygoid lamina 68, pterygoid lamina 68 slides and sets up in spacing groove 67, be connected with reset spring 69 between movable block 66 bottom and the blind hole 65 bottom, blind hole 65 bottom is equipped with micro-gap switch 71, movable block 66 bottom is equipped with lug 70, micro-gap switch 71's contact position and lug 70 central point put correspondingly, be equipped with first articulated seat 62 on the ejector pin 28, be equipped with the articulated seat 64 of second on the support shell 25, it has telescopic pump 63 to articulate between first articulated seat 62 and the articulated seat 64 of second, micro-gap.

When the brake block 57 contacts the support rod 18, the movable rod 66 is pressed to retract into the blind hole 65, the bump 70 at the bottom of the movable block 66 presses the contact on the microswitch 71, and the microswitch 71 sends a signal to the telescopic pump 63, so that the telescopic pump 63 adjusts the ejector rod to a specified position to form the first layer anti-falling again.

The left side and the right side of the connecting block 8 are both connected with a plurality of reinforcing beams 10, the inner sides of the support frames 1 are both provided with ear plates 9, and one ends, far away from the connecting block 8, of the reinforcing beams 10 are fixedly connected with the ear plates 9.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may occur to those skilled in the art without departing from the principle of the invention, and are considered to be within the scope of the invention.

Claims

1. A lifting scaffold with an anti-falling function comprises a support frame, support frames, support plates and connecting blocks, wherein the support frame is provided with two groups, the support frames are arranged above the support frame, the support plates are arranged on the upper portion of the support frame, foot supporting units are arranged on the outer side of the lower portion of the support frame, a plurality of reinforcing beams are connected to the left side and the right side of each connecting block, ear plates are arranged on the inner sides of the support frames, one ends, away from the connecting blocks, of the reinforcing beams are fixedly connected with the ear plates, the support frame comprises two vertical beams, a plurality of cross beams are connected between the two vertical beams, four support rods are connected to the lower portion of the support frame, the lower portions of the four support rods are respectively inserted into the vertical beams, racks are arranged on the front sides of the support rods, a lifting motor frame is arranged, the middle part of the gear shaft is provided with a gear, the vertical beam is provided with an opening, the gear penetrates through the opening on the vertical beam to be meshed with the rack, a moving block is arranged in the supporting frame in a sliding manner, the right side of the supporting frame is provided with a lead screw motor seat, the upper part of the lead screw motor seat is provided with a lead screw motor, the moving block is provided with a threaded hole along the length direction of the supporting frame, a lead screw is arranged in the threaded hole, one end of the lead screw is connected with an output shaft of the lead screw motor, the upper part of the moving block is connected with a supporting plate, the upper part of the supporting plate is provided with a circle of guardrails, the foot supporting unit comprises a mounting plate fixed on the vertical beam, the front side of the mounting plate is sequentially provided with a first rotating seat, a second rotating seat and a third rotating seat from top to bottom, rotating shafts are rotatably arranged on, the foot supporting plate is connected between the first reinforcing plate and the second reinforcing plate, a shock absorption block is arranged at the lower part of the foot supporting plate, clamping holes are formed in the foot supporting plate, a first clamping block and a second clamping block are respectively arranged at the positions, located on the left side and the right side of the rotating shaft, of the front side of the mounting plate, clamping grooves are formed in the first clamping block and the second clamping block, the height of each clamping groove in the first clamping block is higher than that of each clamping groove in the second clamping block, a spring is sleeved on the rotating shaft and located between the second rotating seat and the first reinforcing plate, and when the foot supporting plate rotates by taking the rotating shaft as a shaft, the clamping holes can be clamped into the clamping grooves of the first clamping block or the second clamping block for fixation; the anti-falling mechanism is arranged on the vertical beam and comprises a supporting shell, the supporting shell is fixed on one side, opposite to the gear, of the vertical beam, the cross section of the supporting shell is U-shaped, a first fixing shaft and a second fixing shaft are fixedly connected in the supporting shell, the first fixing shaft is positioned above the second fixing shaft, a first sleeve is sleeved on the first fixing shaft, a mandril is fixed on the first sleeve, the lower portion of the mandril is connected with a first tension spring, a fixing seat is fixed on the right side wall of the supporting shell and is L-shaped, one end, far away from the mandril, of the first tension spring is connected with a horizontal section of the fixing seat, a first stop block is arranged at a position below the first sleeve in the supporting shell, a second sleeve is sleeved on the second fixing shaft, a brake block is fixed on the second sleeve, and two connecting plates are fixedly connected at positions, lower portion of the brake block, on the second sleeve, an activating block is rotatably arranged between the two connecting plates, a second stop block is arranged at a position below the second sleeve in the supporting shell, and a second tension spring is connected between the brake block and the vertical section of the fixed seat;

the brake block is characterized in that a blind hole is formed in the upper part of the brake block, a movable block is arranged in the blind hole, limiting grooves are formed in positions, located on two sides of each limiting groove, in the brake block, wing plates are connected to the left side and the right side of each movable block, the wing plates are arranged in the limiting grooves in a sliding mode, a reset spring is connected between the bottom of each movable block and the bottom of the corresponding blind hole, a microswitch is arranged at the bottom of each blind hole, a protruding block is arranged at the bottom of each movable block, the contact position of the microswitch corresponds to the central position of the protruding block, a telescopic pump is hinged between;

the utility model discloses a support frame, including support frame, walking unit, link, embedded groove, link sub-unit, link card and connecting beam, the link is provided with two removal wheel seats, it is provided with the removal wheel to rotate in the removal wheel seat, the embedded groove has been seted up on the perpendicular roof beam, embedded groove sub-unit connection has the spout, the slider passes embedded groove card and goes into in the perpendicular roof beam, the link can remove along the spout, erect the position that lies in the spout left and right sides on the roof beam and seted up two regulation holes, two the vertical setting of regulation hole is just parallel to each other, it has fixing bolt to twist on the regulation hole, be equipped with the fixed orifices on the slider, the fixing bolt front end passes behind the fixed orifices on the slider and the inner wall butt of erecting the roof beam.

2. The lifting scaffold with the anti-falling function according to claim 1, characterized in that: two guide grooves are formed in the supporting frame along the length direction, a plurality of idler wheels are arranged on the lower portion of the supporting plate, and the lower portions of the idler wheels are located in the guide grooves.