CN215622792U

CN215622792U - Follow-up helicopter maintenance lifting working ladder with self-locking device

Info

Publication number: CN215622792U
Application number: CN202121450957.8U
Authority: CN
Inventors: 徐志尧; 陈晓康
Original assignee: Tianjin Zhonghang Jinjiang Aviation Maintenance Engineering Co ltd
Current assignee: Tianjin Zhonghang Jinjiang Aviation Maintenance Engineering Co ltd
Priority date: 2021-06-28
Filing date: 2021-06-28
Publication date: 2022-01-25
Anticipated expiration: 2031-06-28

Abstract

The application provides a follow-up helicopter maintenance lifting working ladder with a self-locking device, and belongs to the technical field of maintenance working ladders. The follow-up helicopter overhauling lifting working ladder with the self-locking device comprises a fixing assembly, a lifting assembly and a self-locking assembly. Fixed subassembly includes bottom plate, first ladder step, first workstation, second ladder step, second workstation and universal wheel, lifting unit includes first pivot, second pivot, lead screw, fixed plate and bracing piece, the auto-lock subassembly includes first threaded rod, fixing base and auto-lock gear. This device can highly adjust the work ladder, has improved the application scope of equipment, and this device passes through the setting of stopper and auto-lock gear simultaneously, has reached the purpose of auto-lock, prevents that first pivot from rotating under the collision of foreign object, has improved the security of equipment, and can descend the recovery to second ladder step and second workstation, has effectively reduced the volume of equipment, and then is convenient for remove.

Description

Follow-up helicopter maintenance lifting working ladder with self-locking device

Technical Field

The application relates to the field of maintenance working ladders, in particular to a follow-up helicopter maintenance lifting working ladder with a self-locking device.

Background

When the aircraft is maintained or detected by the crew, the detection and the maintenance are finished by the assistance of the working ladder when the normal height of the crew is not reached, the lifting working ladder is mainly used for the carrying personnel to maintain the wings, the fuselage, the engine and other parts of the aircraft, and the carrying personnel performs the work of checking, lubricating, repairing, troubleshooting, debugging and the like during various kinds of aircraft preparation and regular maintenance of the aircraft. When the lifting working ladder commonly used at present is used and the height of a working table needs to be adjusted, the lifting working ladder needs to be lifted, positioned and fixed every time, the steps are complicated, and the equipment is large in size and not convenient to move.

SUMMERY OF THE UTILITY MODEL

In order to compensate for above not enough, this application provides a follow-up helicopter maintenance lift work ladder of taking self-lock device, aims at improving the problem of adjusting the lift to its location and fixed comparatively loaded down with trivial details and the big not convenient for remove of workstation at every turn.

The embodiment of the application provides a follow-up helicopter overhauling lifting working ladder with a self-locking device, which comprises a fixing assembly, a lifting assembly and a self-locking assembly.

Fixed subassembly includes bottom plate, first ladder step, first workstation, second ladder step, second workstation and universal wheel, the surface mounting of bottom plate has two risers, first ladder step fixed connection in the bottom plate, first workstation fixed connection in first ladder step one end, second ladder step rotate install in the one end of first workstation, the first articulated seat of both sides fixedly connected with of second ladder step, the second workstation rotate install in the one end of second ladder step, universal wheel fixed connection in the bottom surface of bottom plate.

The lifting component comprises a first rotating shaft, a second rotating shaft, a lead screw, a fixed plate and a supporting rod, wherein one end of the first rotating shaft is rotatably installed in the bottom plate, the second rotating shaft is rotatably installed in the bottom plate, the first rotating shaft is in meshed transmission with the second rotating shaft, the lead screw is rotatably installed in the vertical plate, one end of the lead screw is rotatably penetrated through the bottom plate and in meshed transmission with the second rotating shaft, the fixed plate is provided with two fixed plates, the fixed plate is in threaded sleeve joint with the outer wall of the lead screw, one fixed plate is provided with a hinged seat of the second, two ends of the supporting rod are respectively rotatably sleeved with the hinged seat of the first hinged seat and the hinged seat of the second, the other fixed plate is provided with a sliding rod, and the other end of the sliding rod is slidably installed at the bottom of the second workbench.

The self-locking assembly comprises a first threaded rod, a fixing seat and a self-locking gear, one end of the first threaded rod is installed in the bottom plate in a threaded mode, one end of the first threaded rod is installed on the surface of the fixing seat, a third rotating shaft is installed in the fixing seat in a rotating mode, a limiting block is fixedly sleeved on the outer wall of the third rotating shaft, the self-locking gear is in keyed connection with the first rotating shaft, and the limiting block is in limited fit with the self-locking gear.

In the implementation process, the first rotating shaft, the second rotating shaft, the screw rod and the fixed seat are arranged, so that the height of the second ladder step and the height of the second workbench are conveniently raised, thereby achieving the purpose of adjusting the height, improving the application range of the equipment, simultaneously, through the arrangement of the self-locking gear, the fixed seat, the rotating shaft and the limited block, the self-locking gear is limited, the automatic rotation of the first rotating shaft is prevented, the use of the equipment is further influenced, through the arrangement, the device can adjust the height of the working ladder, improves the application range of the equipment, meanwhile, the device achieves the self-locking purpose through the arrangement of the limiting block and the self-locking gear, prevents the first rotating shaft from rotating under the collision of foreign objects, improves the safety of the equipment, and can descend to retrieve with the second workstation to the second ladder step, effectively reduce the volume of equipment, and then be convenient for remove.

In a specific embodiment, an X-shaped bracket is fixedly connected to the bottom of the first workbench, and one end of the X-shaped bracket, which is far away from the first workbench, is fixedly connected to the surface of the bottom plate.

In the implementation process, the X-shaped support is arranged to support the first workbench, so that the stability and the bearing performance of the first workbench are improved.

In a specific embodiment, a first gear is fixedly connected to one end of the first rotating shaft, a second gear is fixedly connected to both ends of the second rotating shaft, and the first gear is meshed with one of the second gears.

In the implementation process, the first gear and the second gear are arranged, so that the first rotating shaft can conveniently drive the second rotating shaft to rotate, and meanwhile, the gear transmission has the characteristic of stable transmission.

In a specific embodiment, one end of the screw rod is fixedly connected with a third gear, and the third gear is meshed with the other second gear.

In the implementation process, the second gear and the third gear are arranged, so that the second rotating shaft can conveniently drive the screw rod to rotate, and meanwhile, the gear transmission has the characteristic of stable transmission.

In a specific embodiment, a rotating disc is arranged at one end of the first rotating shaft, and the rotating disc is fixedly connected to one end of the first rotating shaft.

In the implementation process, the first rotating shaft is conveniently rotated through the rotating disc in operation through the arrangement of the rotating disc, and the purposes of time saving and labor saving are achieved.

In a specific implementation scheme, a sliding block is arranged at one end of the sliding rod, a sliding groove is formed in the bottom surface of the second workbench, and the sliding block is slidably mounted in the sliding groove.

In the implementation process, the sliding block and the sliding groove are arranged, so that the movement of the second workbench is limited, and the movement of the second workbench is more stable.

In a specific embodiment, handrails are mounted on the surfaces of the first step, the first workbench, the second step and the second workbench.

In the implementation process, the handrail is arranged, so that the operator can hold the handrail conveniently, and the safety is improved.

In a specific embodiment, the outer wall of the screw rod is sleeved with a nut seat in a threaded manner, and the two fixing plates are fixedly connected to two sides of the nut seat.

In the implementation process, the nut seat is conveniently driven to reciprocate along the screw rod through the arrangement of the nut seat.

In a specific embodiment, a limiting rod is installed in the vertical plate, and the nut seat is sleeved on the outer wall of the limiting rod in a sliding mode.

In the implementation process, the limiting rod is arranged, so that the movement of the nut seat is limited, and the nut seat is more stable in movement.

In a specific embodiment, the fixing assembly further comprises a telescopic leg, the telescopic leg comprises a threaded column, a second threaded rod and a support leg, the threaded column is fixedly connected to one side of the bottom plate, the second threaded rod is installed in the threaded column in a threaded mode, and the support leg is fixedly connected to one end of the second threaded rod.

In the implementation process, the supporting legs are arranged in a telescopic mode, the supporting legs are in contact with the ground by rotating the second threaded rod on the premise that the equipment is not influenced to move, and therefore the stability of the equipment is improved.

Drawings

In order to more clearly explain the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that for those skilled in the art, other related drawings can be obtained from these drawings without inventive effort.

FIG. 1 is a schematic structural view of a follow-up helicopter maintenance lifting working ladder with a self-locking device provided by the embodiment of the application;

fig. 2 is a schematic structural view of the follow-up helicopter overhauling lifting working ladder with the self-locking device provided by the embodiment of the application in another state;

FIG. 3 is a schematic diagram of a bottom plate structure provided in an embodiment of the present application;

fig. 4 is a schematic structural diagram of a base plate from another view angle according to an embodiment of the present disclosure;

FIG. 5 is an enlarged view of the location A in FIG. 3 according to an embodiment of the present disclosure;

fig. 6 is a schematic structural view of a telescopic leg provided in an embodiment of the present application;

fig. 7 is a schematic view of a fixing base structure according to an embodiment of the present disclosure.

In the figure: 100-a stationary component; 110-a base plate; 111-riser; 1111-a limiting rod; 120-a first ladder step; 121-a handrail; 130-a first stage; 131-X type stent; 140-a second ladder step; 141-a first articulated seat; 150-a second stage; 151-a chute; 160-universal wheels; 170-telescopic legs; 171-threaded post; 172-a second threaded rod; 173-a leg; 200-a lifting assembly; 210-a first shaft; 211-a first gear; 212-a rotating disc; 220-a second rotating shaft; 221-a second gear; 230-a screw rod; 231-a third gear; 232-nut seat; 240-a fixed plate; 241-a second articulated mount; 242-a slide bar; 2421-a slider; 250-support rods; 300-a self-locking assembly; 310-a first threaded rod; 320-a fixed seat; 321-a third rotating shaft; 322-a stop block; 330-self-locking gear.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.

To make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art without any inventive work based on the embodiments in the present application are within the scope of protection of the present application.

Thus, the following detailed description of the embodiments of the present application, as presented in the figures, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments obtained by a person of ordinary skill in the art without any inventive work based on the embodiments in the present application are within the scope of protection of the present application.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and thus should not be considered limiting.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact of the first and second features, or may comprise contact of the first and second features not directly but through another feature in between. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

Referring to fig. 1 and 4, the present application provides a follow-up helicopter maintenance lift working ladder with a self-locking device, which includes a fixing assembly 100, a lifting assembly 200 and a self-locking assembly 300.

Referring to fig. 1, 2, 3, 4, 5 and 6, the fixing assembly 100 includes a base plate 110, a first step 120, a first working platform 130, a second step 140, a second working platform 150 and a universal wheel 160, two risers 111 are mounted on the surface of the base plate 110, the first step 120 is fixedly connected to the base plate 110, the first working platform 130 is fixedly connected to one end of the first step 120, the bottom of the first working platform 130 is fixedly connected to an X-shaped bracket 131, one end of the X-shaped bracket 131 far away from the first working platform 130 is fixedly connected to the surface of the base plate 110, when specifically configured, the X-shaped bracket 131 is arranged to support the first working platform 130, so as to improve the stability and the load-bearing performance of the first working platform 130, the second step 140 is rotatably mounted at one end of the first working platform 130, handrails 121 are mounted on the surfaces of the first step 120, the first working platform 130, the second step 140 and the second working platform 150, when specifically setting up, through the setting of handrail 121, it is convenient for the operator to hold, the security has been improved, the first articulated seat 141 of both sides fixedly connected with of second ladder step 140, second workstation 150 rotates and installs in the one end of second ladder step 140, universal wheel 160 fixed connection is in the bottom surface of bottom plate 110, fixed subassembly 100 is still including flexible landing leg 170, flexible landing leg 170 is including threaded post 171, second threaded rod 172 and stabilizer blade 173, threaded post 171 fixed connection is in one side of bottom plate 110, second threaded rod 172 is threaded to be installed in threaded post 171, stabilizer blade 173 fixed connection is in the one end of second threaded rod 172, when specifically setting up, through the setting of flexible landing leg 170, under the prerequisite that does not influence equipment removal, make stabilizer blade 173 and ground contact through rotating second threaded rod 172, and then the stability of equipment has been improved.

Referring to fig. 1, 2, 3, 4 and 5, the lifting assembly 200 includes a first rotating shaft 210, a second rotating shaft 220, a screw 230, a fixing plate 240 and a support rod 250, one end of the first rotating shaft 210 is rotatably installed in the bottom plate 110, one end of the first rotating shaft 210 is provided with a rotating disc 212, the rotating disc 212 is fixedly connected to one end of the first rotating shaft 210, it should be noted that, by the arrangement of the rotating disc 212, it is convenient for the operation to rotate the first rotating shaft 210 through the rotating disc 212, so as to achieve the purpose of saving time and labor, the second rotating shaft 220 is rotatably installed in the bottom plate 110, the first rotating shaft 210 is in meshing transmission with the second rotating shaft 220, one end of the first rotating shaft 210 is fixedly connected with a first gear 211, two ends of the second rotating shaft 220 are fixedly connected with second gears 221, the first gear 211 is in meshing with one of the second gears 221, it should be noted that, the first gear 211 and the second gear 221 are arranged, the first rotating shaft 210 is convenient to drive the second rotating shaft 220 to rotate, meanwhile, the gear transmission has the characteristic of smooth transmission, the screw rod 230 is rotatably installed in the vertical plate 111, one end of the screw rod 230 rotatably penetrates through the bottom plate 110 and is in meshed transmission with the second rotating shaft 220, one end of the screw rod 230 is fixedly connected with a third gear 231, the third gear 231 is mutually meshed with another second gear 221, in the application, the second rotating shaft 220 is convenient to drive the screw rod 230 to rotate through the arrangement of the second gear 221 and the third gear 231, meanwhile, the gear transmission has the characteristic of smooth transmission, two fixing plates 240 are arranged, the two fixing plates 240 are in threaded sleeve connection with the outer wall of the screw rod 230, the outer wall of the screw rod 230 is in threaded sleeve connection with the nut seat 232, the two fixing plates 240 are fixedly connected to two sides of the nut seat 232, in the application, the nut seat 232 is convenient to drive the nut seat 232 to reciprocate along the screw rod 230 through the arrangement of the nut seat 232, install gag lever post 1111 in riser 111, nut seat 232 slides and cup joints in the outer wall of gag lever post 1111, in this embodiment, through the setting of gag lever post 1111, play spacing effect to the motion of nut seat 232, it is more stable when making nut seat 232 move, the surface mounting of a fixed plate 240 has articulated seat 241 of second, the both ends of bracing piece 250 rotate respectively and cup joint in articulated seat 141 of first and second 241, another fixed plate 240 surface mounting has slide bar 242, the other end slidable mounting of slide bar 242 is provided with slider 2421 in the one end of the bottom slide bar 242 of second workstation 150, spout 151 has been seted up on the bottom surface of second workstation 150, slider 2421 slidable mounting is in spout 151, in this embodiment, through the setting of slider 2421 and spout 151, play spacing effect to the motion of second workstation 150, make the motion of second workstation 150 more stable.

Referring to fig. 4, 5 and 7, the self-locking assembly 300 includes a first threaded rod 310, a fixing base 320 and a self-locking gear 330, wherein one end of the first threaded rod 310 is threadedly mounted in the bottom plate 110, one end of the first threaded rod 310 is mounted on the surface of the fixing base 320, a third rotating shaft 321 is rotatably mounted in the fixing base 320, a limiting block 322 is fixedly sleeved on the outer wall of the third rotating shaft 321, the self-locking gear 330 is connected to the first rotating shaft 210 in a key manner, and the limiting block 322 is in limiting fit with the self-locking gear 330.

The working principle of the follow-up helicopter with the self-locking device for overhauling the lifting working ladder is as follows: when the height of the device needs to be adjusted, the first rotating shaft 210 is rotated to drive the first gear 211 to rotate, the first gear 211 is rotated to drive the second gear 221 to rotate, the second gear 221 is rotated to drive the second rotating shaft 220 to rotate, and then the third gear 231 is driven to rotate by the other second gear 221, the third gear 231 is rotated to drive the screw rod 230 to rotate, the screw rod 230 is rotated to drive the nut seat 232 to move, and then the two fixing plates 240 are driven to move, while the two fixing plates 240 move, one fixing plate 240 pushes the second ladder step 140 to ascend through the second hinge seat 241 and the support rod 250, the other fixing plate 240 drives the second workbench 150 to ascend through the slide rod 242, and then the height of the device is adjusted, because the fixing seat 320, the third rotating shaft 321, the limit block 322 and the self-locking gear 330 are arranged, the self-locking gear 330 is limited and fixed, and further the first rotating shaft 210 is prevented from rotating, the purpose of auto-lock has been reached, the security of equipment has been improved, after the use is accomplished, drive the decline of fixing base 320 through first threaded rod 310, and then remove spacing to self-locking gear 330, can retrieve through first pivot 210 drive second ladder step 140 and second workstation 150 and reset, this device can highly adjust the workstation, the application scope of equipment has been improved, this device passes through stopper 322 and self-locking gear 330's setting simultaneously, the purpose of auto-lock has been reached, prevent that first pivot 210 from rotating under the collision of foreign object, the security of equipment has been improved, and can descend second ladder step 140 and second workstation 150 and retrieve, the volume of equipment has effectively been reduced, and then be convenient for remove.

The above description is only an example of the present application and is not intended to limit the scope of the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A follow-up helicopter maintenance lifting working ladder with a self-locking device is characterized by comprising

The fixing assembly (100) comprises a base plate (110), a first ladder step (120), a first workbench (130), a second ladder step (140), a second workbench (150) and universal wheels (160), wherein two vertical plates (111) are mounted on the surface of the base plate (110), the first ladder step (120) is fixedly connected to the base plate (110), the first workbench (130) is fixedly connected to one end of the first ladder step (120), the second ladder step (140) is rotatably mounted at one end of the first workbench (130), two sides of the second ladder step (140) are fixedly connected with first hinge seats (141), the second workbench (150) is rotatably mounted at one end of the second ladder step (140), and the universal wheels (160) are fixedly connected to the bottom surface of the base plate (110);

lifting assembly (200), lifting assembly (200) includes first pivot (210), second pivot (220), lead screw (230), fixed plate (240) and bracing piece (250), the one end of first pivot (210) rotate install in bottom plate (110), second pivot (220) rotate install in bottom plate (110), first pivot (210) with second pivot (220) meshing transmission, lead screw (230) rotate install with riser (111) in, the one end of lead screw (230) rotate run through in bottom plate (110) and with second pivot (220) meshing transmission, fixed plate (240) are provided with two, two fixed plate (240) screw thread cup joints in on the outer wall of lead screw (230), the surface mounting of one fixed plate (240) has articulated seat (241) of second, the both ends of bracing piece (250) rotate respectively cup joint in first articulated seat (141) with articulated seat (241) of second, (240) are connected to the bracing piece 241) A sliding rod (242) is installed on the surface of the other fixing plate (240), and the other end of the sliding rod (242) is installed at the bottom of the second workbench (150) in a sliding manner;

auto-lock subassembly (300), auto-lock subassembly (300) include first threaded rod (310), fixing base (320) and auto-lock gear (330), the one end screw thread of first threaded rod (310) install in bottom plate (110), the one end dress of first threaded rod (310) install in fixing base (320) surface, third pivot (321) are installed to fixing base (320) internal rotation, stopper (322) have been cup jointed to the outer wall of third pivot (321) is fixed, auto-lock gear (330) key-type connect in first pivot (210), stopper (322) with auto-lock gear (330) spacing cooperation.

2. The follow-up helicopter overhauling lifting working ladder with the self-locking device according to claim 1, wherein an X-shaped bracket (131) is fixedly connected to the bottom of the first working platform (130), and one end of the X-shaped bracket (131) far away from the first working platform (130) is fixedly connected to the surface of the bottom plate (110).

3. The follow-up helicopter overhauling lifting working ladder with the self-locking device as claimed in claim 1, wherein a first gear (211) is fixedly connected to one end of the first rotating shaft (210), a second gear (221) is fixedly connected to both ends of the second rotating shaft (220), and the first gear (211) is meshed with one of the second gears (221).

4. A follow-up helicopter service lift with self-locking device according to claim 3 characterized in that a third gear (231) is fixedly connected to one end of said screw rod (230), said third gear (231) is meshed with another said second gear (221).

5. The follow-up helicopter overhauling lifting working ladder with the self-locking device as recited in claim 1, wherein a rotating disc (212) is arranged at one end of the first rotating shaft (210), and the rotating disc (212) is fixedly connected to one end of the first rotating shaft (210).

6. The follow-up helicopter overhauling lifting working ladder with the self-locking device according to claim 1, wherein a sliding block (2421) is arranged at one end of the sliding rod (242), a sliding groove (151) is formed in the bottom surface of the second working table (150), and the sliding block (2421) is slidably mounted in the sliding groove (151).

7. The follow-up helicopter overhauling lifting working ladder with the self-locking device as claimed in claim 1, wherein handrails (121) are mounted on the surfaces of the first ladder step (120), the first working platform (130), the second ladder step (140) and the second working platform (150).

8. The follow-up helicopter overhauling lifting working ladder with the self-locking device as recited in claim 1, wherein a nut seat (232) is sleeved on the outer wall of the screw rod (230) in a threaded manner, and the two fixing plates (240) are fixedly connected to two sides of the nut seat (232).

9. The follow-up helicopter overhauling lifting working ladder with the self-locking device as claimed in claim 8, wherein a limit rod (1111) is installed in the vertical plate (111), and the nut seat (232) is slidably sleeved on the outer wall of the limit rod (1111).

10. The follow-up helicopter overhauling lifting working ladder with the self-locking device as claimed in claim 1, wherein the fixing assembly (100) further comprises a telescopic leg (170), the telescopic leg (170) comprises a threaded column (171), a second threaded rod (172) and a supporting foot (173), the threaded column (171) is fixedly connected to one side of the bottom plate (110), the second threaded rod (172) is installed in the threaded column (171) in a threaded manner, and the supporting foot (173) is fixedly connected to one end of the second threaded rod (172).