CN216607592U

CN216607592U - Be used for metal furniture automatic spot welding robot

Info

Publication number: CN216607592U
Application number: CN202122946561.9U
Authority: CN
Inventors: 章国强; 章莉妍; 崔炳涛
Original assignee: Johnson Huizhou Home Development Co ltd
Current assignee: Johnson Huizhou Home Development Co ltd
Priority date: 2021-11-26
Filing date: 2021-11-26
Publication date: 2022-05-27
Anticipated expiration: 2031-11-26

Abstract

The utility model belongs to the technical field of metal furniture processing, and particularly relates to an automatic spot welding robot for metal furniture, which comprises a first positioning mechanism and a second positioning mechanism; three groups of first positioning blocks are arranged; the second positioning mechanism is provided with a movable end which can move along a preset direction; the three groups of first positioning mechanisms and the three groups of second positioning mechanisms are arranged in a rectangular shape, the movable end of the second positioning mechanism and the three groups of first positioning mechanisms are provided with two positioning surfaces for positioning, and the two positioning surfaces are respectively used for abutting against two adjacent workpieces to be welded. Therefore, the position accuracy of the placed workpieces is improved, two adjacent workpieces are tightly and firmly attached together, the welding effect is greatly improved, and the service life of the frame is prolonged.

Description

Be used for metal furniture automatic spot welding robot

Technical Field

The utility model belongs to the technical field of metal furniture processing, and particularly relates to an automatic spot welding robot for metal furniture.

Background

The metal furniture is mainly constructed by metal pipes, plates or rods and the like, and is matched with furniture made of wood, various artificial boards, glass, stone and the like and iron art furniture made of metal materials, and is generally called as metal furniture. Most furniture is provided with a supporting and overall rectangular frame, and the frames are formed by welding four metal pieces. In the prior art, four pieces of metal are typically welded into a frame by spot welding robots. However, the existing spot welding robot lacks a positioning mechanism, which causes the welding quality of the frame to be reduced, and further influences the service life of the frame.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide an automatic spot welding robot for metal furniture, and aims to solve the technical problem that a spot welding robot in the prior art is poor in welding effect.

In order to achieve the above object, an automatic spot welding robot for metal furniture provided by the embodiment of the utility model comprises a first positioning mechanism and a second positioning mechanism; three groups of first positioning blocks are arranged; the second positioning mechanism is provided with a movable end which can move along a preset direction; the three groups of first positioning mechanisms and the second positioning mechanisms are arranged in a rectangular mode, the movable end of the second positioning mechanism and the three groups of first positioning mechanisms are provided with two positioning surfaces for positioning, and the two positioning surfaces are used for abutting against two adjacent workpieces to be welded respectively.

Optionally, the spot welding robot further comprises a supporting device and a spot welding robot main body; the fixed end of the second positioning mechanism, the fixed end of the spot welding robot main body and the three groups of first positioning mechanisms are fixedly arranged on the supporting device; the spot welding robot main body is used for welding two adjacent workpieces to be welded.

Optionally, the first positioning mechanism includes a first positioning block and a first mounting block; the first mounting block is provided with at least one block, and the upper surface and the lower surface of the first mounting block are respectively and fixedly connected with the bottom surface of the first positioning block and the top surface of the supporting device; the first positioning block is provided with two positioning surfaces for positioning.

Optionally, the cross section of the first positioning block is V-shaped.

Optionally, the second positioning mechanism includes a second driving unit and a pushing block; the fixed end of the second driving unit is fixedly arranged on the supporting device; the second driving unit is in linkage connection with the pushing block so as to enable the pushing block to move, and therefore a workpiece to be welded is fixed.

Optionally, the drive unit comprises a cylinder; the cylinder is installed on the supporting device, and the telescopic end of the cylinder is fixedly connected with the push block.

Optionally, the second positioning mechanism further comprises a guide assembly; the guide assembly is arranged on the supporting device and used for guiding the push block.

Optionally, the guide assembly comprises two pins; the two pins are embedded on the supporting device and are respectively positioned at the left end and the right end of the push block.

Optionally, the supporting device comprises a base, a rotating mechanism and a turntable; the rotating mechanism is provided with a rotatable movable end; the movable end of the rotating mechanism is fixedly connected with the turntable, and the fixed end of the rotating mechanism is fixedly connected with the base; the fixed end of the spot welding robot main body is fixedly arranged on the base and is positioned on the outer side of the rotary table; the fixed end of the second positioning mechanism and the three groups of first positioning mechanisms are fixedly arranged on the turntable; the rotating mechanism drives the turntable and all the workpieces to rotate by a preset angle, so that the spot welding robot main body can weld two adjacent workpieces to be welded.

Optionally, the rotating mechanism comprises a first drive unit and a worm gear reducer; the first driving unit and the worm gear reducer are both arranged on the base, and the first driving unit is in linkage connection with the worm gear reducer; and the output shaft of the worm gear reducer is fixedly connected with the turntable so as to enable the turntable to rotate.

The technical scheme or the technical schemes used in the automatic spot welding robot for the metal furniture provided by the embodiment of the utility model at least have one of the following technical effects: it should be noted that the frame is composed of four metal workpieces, and the cross section of the frame is rectangular, that is, the frame has four spot welding positions, and the four spot welding positions are respectively located at four corners of the frame. The three groups of first positioning mechanisms and the second positioning mechanisms are arranged in a rectangular shape, and the movable end of the second positioning mechanism and the three groups of first positioning mechanisms are provided with two positioning surfaces for positioning. When the workpiece positioning device is used, four workpieces are placed in an area formed by the second positioning mechanism and the three groups of first positioning mechanisms together according to the rectangular shape. At the moment, the movable end of the second positioning mechanism and the two positioning surfaces of each first positioning mechanism are respectively contacted with the two adjacent workpieces. It should be noted that the movable end of the second positioning mechanism plays a role in coarse positioning. Then, the movable end of the second positioning mechanism moves forward a small distance to push two workpieces contacted with the movable end of the second positioning mechanism, and the four workpieces are firmly and tightly attached together under the limitation of the three groups of first positioning mechanisms. Therefore, the position accuracy of the placed workpieces is improved, two adjacent workpieces are tightly and firmly attached together, the welding effect is greatly improved, and the service life of the frame is prolonged.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a schematic structural diagram of a stitch welding robot for metal furniture according to an embodiment of the present invention.

Fig. 2 is an assembly schematic diagram of the turntable, the first positioning mechanism and the second positioning mechanism provided in the embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a rotation mechanism according to an embodiment of the present invention.

Fig. 4 is a schematic structural diagram of a first positioning mechanism according to an embodiment of the present invention.

Wherein, in the figures, the respective reference numerals:

10-first positioning mechanism 20-second positioning mechanism 30-supporting device

40-spot welding robot main body 11-first positioning block 12-first mounting block

21-second drive unit 22-push block 31-rotation mechanism

32-turntable 33-base 34-rolling mechanism

311-worm gear reducer 312-first driving motor 313-driving belt pulley

314-driven pulley 315-driving belt 321-clearance groove.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be illustrative of the embodiments of the present invention, and should not be construed as limiting the utility model.

In the description of the embodiments of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the embodiments of the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

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 embodiments of the present invention, "a plurality" means two or more unless specifically limited otherwise.

In the embodiments of the present invention, unless otherwise explicitly specified or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as being fixedly connected, detachably connected, or integrated; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. Specific meanings of the above terms in the embodiments of the present invention may be understood by those of ordinary skill in the art according to specific situations.

In one embodiment of the present invention, as shown in fig. 1 to 4, there is provided a robot for stitch welding of metal furniture, comprising a first positioning mechanism 10 and a second positioning mechanism 20; three groups of first positioning blocks 11 are arranged; the second positioning mechanism 20 has a movable end movable in a predetermined direction; the three groups of first positioning mechanisms 10 and the second positioning mechanisms 20 are arranged in a rectangular shape, the movable end of the second positioning mechanism 20 and the three groups of first positioning mechanisms 10 are provided with two positioning surfaces for positioning, and the two positioning surfaces are respectively used for abutting against two adjacent workpieces to be welded.

Specifically, it should be noted that the frame is composed of four metal workpieces, and the cross section of the frame is rectangular, that is, the frame has four spot welding positions, and the four spot welding positions are located at four corners of the frame respectively. The three groups of first positioning mechanisms 10 and the second positioning mechanisms 20 are arranged in a rectangular shape, and the movable ends of the second positioning mechanisms 20 and the three groups of first positioning mechanisms 10 are provided with two positioning surfaces for positioning. When the positioning device is used, four workpieces are placed in a rectangular shape in an area formed by the second positioning mechanism 20 and the three groups of first positioning mechanisms 10. At this time, the movable end of the second positioning mechanism 20 and the two positioning surfaces of each first positioning mechanism 10 are in contact with the two adjacent workpieces. It is worth mentioning that the movable end of the second positioning mechanism 20 plays a role of coarse positioning. Subsequently, the movable end of the second positioning mechanism 20 moves forward a short distance, so as to push two workpieces in contact with the movable end of the second positioning mechanism 20, and the four workpieces are firmly and tightly attached together under the restriction of the three groups of first positioning mechanisms 10. Therefore, the position accuracy of the placed workpieces is improved, two adjacent workpieces are tightly and firmly attached together, the welding effect is greatly improved, and the service life of the frame is prolonged.

In another embodiment of the present invention, as shown in fig. 1 to 4, the present invention further includes a supporting device 30 and a spot welding robot main body 40; the fixed end of the second positioning mechanism 20, the fixed end of the spot welding robot main body 40 and the three groups of first positioning mechanisms 10 are all fixedly arranged on the supporting device 30; the spot welding robot main body 40 is used for welding two adjacent workpieces to be welded.

In particular, when used. Four workpieces are placed on the supporting device 30 in a rectangular shape, and all four workpieces are located in an area formed by the second positioning mechanism 20 and the three groups of first positioning mechanisms 10. Subsequently, the movable end of the second positioning mechanism 20 moves forward a short distance, so as to push two workpieces in contact with the movable end of the second positioning mechanism 20, and further, the four workpieces are firmly and tightly attached together. Next, the spot welding robot main body 40 performs spot welding on two adjacent workpieces, respectively, that is, the spot welding robot main body 40 performs sequential spot welding work on four spot welding positions, respectively.

In another embodiment of the present invention, as shown in fig. 4, the first positioning mechanism 10 includes a first positioning block 11 and a first mounting block 12; the first mounting block 12 is provided with at least one block, and the upper surface and the lower surface of the first mounting block 12 are respectively and fixedly connected with the bottom surface of the first positioning block 11 and the top surface of the supporting device 30; the first positioning block 11 has two positioning surfaces for positioning.

Specifically, in this embodiment, the first mounting blocks 12 are disposed in two and respectively located at the left and right ends of the first positioning block 11, and the two first mounting blocks 12 are symmetrically disposed. The first positioning block 11 and the two first mounting blocks 12 are integrally formed. Two connecting through holes are formed in the top of the first positioning block 11, the two connecting through holes correspond to the two first mounting blocks 12 respectively, the two connecting through holes extend to the two first mounting blocks 12 respectively, and the two connecting through holes penetrate through the bottom surfaces of the corresponding first mounting blocks 12. Correspondingly, three sets of connecting threaded hole sets are formed in the supporting device 30, and the three sets of connecting threaded hole sets respectively correspond to the three sets of first positioning mechanisms 10. Each connecting threaded hole group comprises two connecting threaded holes, and the two connecting threaded holes are respectively in one-to-one correspondence with the two connecting through holes on the corresponding first positioning mechanisms 10. The detachable connection of the first positioning mechanism 10 and the supporting mechanism can be realized by using the connecting bolt to penetrate through the connecting through hole and be connected with the connecting threaded hole.

Further, the cross section of the first positioning block 11 is in a V shape. In this embodiment, the first positioning block 11 is composed of two cuboids, an included angle between the two cuboids is 90 °, and the first positioning block 11 is integrally formed. So set up, be favorable to reducing the processing degree of difficulty.

In another embodiment of the present invention, as shown in fig. 1-2, the second positioning mechanism 20 includes a second driving unit 21 and a pushing block 22; the fixed end of the second driving unit 21 is fixedly arranged on the supporting device 30; the second driving unit 21 is linked with the pushing block 22 to move the pushing block 22, thereby fixing the workpiece to be welded.

Specifically, the surfaces of the pushing block 22 facing the two adjacent workpieces are provided with positioning grooves with V-shaped cross sections, and the two positioning surfaces of the positioning grooves are respectively in contact with the two workpieces. When the workpieces to be welded are placed, the pushing block 22 plays a role of coarse positioning, so that the four workpieces can be smoothly and smoothly placed in an area formed by the pushing block 22 and the three groups of first positioning blocks 11. When the welding device is used, the second driving unit 21 drives the push block 22 to enable the push block 22 to move towards the direction of the workpiece, so that two adjacent workpieces are pushed, and in this way, the four workpieces are firmly and tightly attached together, and the welding effect is greatly improved.

Further, the driving unit includes a cylinder; the cylinder is arranged on the supporting device 30, and the telescopic end of the cylinder is fixedly connected with the push block 22. The cylinder is prior art and therefore not described in detail herein. The cylinder is cheap, and the assembly degree of difficulty is low.

In another embodiment of the present invention, the second positioning mechanism 20 further comprises a guide assembly; the guiding assembly is arranged on the supporting device 30 and used for guiding the pushing block 22.

Further, the guide assembly comprises two pins; the two pins are embedded in the supporting device 30 and are respectively located at the left end and the right end of the push block 22.

Specifically, the supporting device 30 is provided with two pin holes respectively located at the left and right ends of the pushing block 22, and the two pins are respectively embedded in the two pin holes. When the device is used, the air cylinder drives the push block 22, so that the push block 22 moves forwards along a straight line under the limitation of the two pins, the movement precision is greatly improved, and the welding effect is improved.

In another embodiment of the present invention, as shown in fig. 1 to 3, the supporting device 30 includes a base 33, a rotating mechanism 31 and a turntable 32; the rotating mechanism 31 has a movable end that can rotate; the movable end of the rotating mechanism 31 is fixedly connected with the turntable 32, and the fixed end of the rotating mechanism 31 is fixedly connected with the base 33; the fixed end of the spot welding robot main body 40 is fixedly arranged on the base 33 and is positioned at the outer side of the turntable 32; the fixed end of the second positioning mechanism 20 and the three sets of the first positioning mechanisms 10 are fixed on the turntable 32; the rotating mechanism 31 drives the rotating disc 32 and all the workpieces to rotate by a predetermined angle, so that the spot welding robot main body 40 can weld two adjacent workpieces to be welded.

Specifically, two pin holes are formed in the top surface of the turntable 32, the cylinder is installed in the top of the turntable 32, three sets of connecting threaded holes are formed in the top surface of the turntable 32, and a workpiece is placed on the top of the turntable 32. When the positioning device is used, four workpieces are placed in a rectangular shape in an area formed by the push block 22 and the three groups of first positioning blocks 11. At this time, the two positioning surfaces of the push block 22 and each of the first positioning blocks 11 are in contact with the two adjacent workpieces. Subsequently, the push block 22 is moved forward by a small distance, thereby pushing two workpieces in contact with the push block 22, and further fixing the four workpieces. It is worth mentioning that, in the present embodiment, the spot welding robot main body 40 can perform the spot welding work to the first spot welding position when all the workpieces are put. Then, the movable end of the rotating mechanism 31 drives the turntable 32 to rotate, so that all the workpieces rotate by a preset angle, and the spot welding robot main body 40 can perform spot welding operation on the second spot welding. The above-described process is repeated in this manner, so that the spot welding robot main body 40 can perform spot welding work on four spot welding positions, thereby welding four workpieces into a frame. That is, by providing the rotating mechanism 31 and the turntable 32, four stations are formed, and the spot welding robot main body 40 can weld four workpieces into a frame without changing the working position, which is advantageous to reduce the production cost.

In another embodiment of the present invention, as shown in fig. 3, the rotating mechanism 31 includes a first driving unit and a worm gear reducer 311; the first driving unit and the worm gear reducer 311 are both arranged on the base 33, and the first driving unit is in linkage connection with the worm gear reducer 311; the output shaft of the worm gear reducer 311 is fixedly connected to the rotary plate 32, so that the rotary plate 32 rotates.

Specifically, the worm gear reducer 311 is prior art and therefore will not be described in detail herein. In the present embodiment, the first drive unit has an output end that rotates about a horizontal axis, and the worm gear reducer 311 has an input shaft that rotates about a horizontal axis and an output shaft that rotates about a vertical axis. The output end of the first driving unit is linked with the input shaft of the worm gear reducer 311, and the output shaft of the worm gear reducer 311 is fixedly connected with the turntable 32. In use, the first driving unit drives the input shaft of the worm gear reducer 311 to rotate, so as to drive the output shaft of the worm gear reducer 311 to rotate around the vertical shaft, and further drive the rotary table 32 and all the workpieces thereon to rotate. The worm and gear speed reducer 311 is adopted, so that the torque is large, the overload capacity is high, the operation is stable, and the noise is low, in addition, the worm and gear speed reducer 311 also has a self-locking function, and the practicability is greatly improved.

Further, the first driving unit includes a first driving motor 312, a driving pulley 313, a driven pulley 314, and a driving belt 315. The first driving motor 312 is installed in the base 33, the worm gear reducer 311 is installed on the top of the base 33, and the turntable 32 is installed on the top of the worm gear reducer 311. The driving pulley 313 is fixedly sleeved on an output shaft of the first driving motor 312, the driven pulley 314 is fixedly sleeved on an input shaft of the worm gear reducer 311, the head end and the tail end of the driving belt 315 are respectively sleeved on the driving pulley 313 and the driven pulley 314, and the driving pulley 313 and the driven pulley 314 form a belt driving structure. When in use, the first driving motor 312 drives the driving pulley 313 to rotate, and under the action of the driving belt 315, the driven pulley 314 rotates, so as to drive the input shaft of the worm gear reducer 311 to rotate, and further drive the output shaft of the worm gear reducer 311 and the turntable 32 to rotate. In the present embodiment, the diameter of the driving pulley 313 is smaller than that of the driven pulley 314 to increase torque.

In another embodiment of the present invention, as shown in fig. 2, four empty-avoiding slots 321 are formed on the turntable 32, the four empty-avoiding slots 321 correspond to four corners of the frame, i.e. four spot welding positions, respectively, and the four empty-avoiding slots 321 penetrate through the turntable 32. Therefore, two adjacent workpieces can be subjected to spot welding from the upper part and the lower part, the welding effect is greatly improved, and the service life is prolonged.

It should be noted that the upper surfaces of the push block 22 and the three first positioning blocks 11 are lower than the upper surface of the workpiece, and the lower surfaces of the push block 22 and the three first positioning blocks 11 are higher than the lower surface of the workpiece, so that the damage of the spot welding robot main body 40 to the push block 22 and the three first positioning blocks 11 can be avoided.

In another embodiment of the present invention, as shown in FIG. 1, the support device 30 further comprises four sets of rolling mechanisms 34; four sets of rolling mechanisms 34 are arranged in an annular array about the axis of the turntable 32. Each of the four rolling mechanisms 34 includes a fixed seat and a roller; the fixing seats are fixedly arranged at the top of the base 33, and the rollers are rotatably connected with the corresponding fixing seats. The turntable 32 is in contact with the rollers. So set up, provide the holding power for carousel 32, avoid the outside of carousel 32 not bearing the weight and fracture. In addition, the contact between the rollers and the turntable 32 is beneficial to reducing the friction force applied to the turntable 32 during rotation, thereby reducing energy loss.

Note that the spot welding robot main body 40 includes a six-axis robot arm and a spot welding head. Six manipulators are installed on base 33, and the spot welder head is used for spot welding, and it installs on six manipulators, and under the drive of six manipulators, spot welder head can move to suitable position and carry out spot welding work. The six-axis manipulator and the spot welding machine head belong to the prior art, and are common in the market, so the details are not repeated herein.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the utility model, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. The utility model provides a be used for metal furniture automatic spot welding robot which characterized in that: comprises that

A first positioning mechanism; three groups of first positioning blocks are arranged;

and a second positioning mechanism; the second positioning mechanism is provided with a movable end which can move along a preset direction;

the three groups of first positioning mechanisms and the second positioning mechanisms are arranged in a rectangular mode, the movable end of the second positioning mechanism and the three groups of first positioning mechanisms are provided with two positioning surfaces for positioning, and the two positioning surfaces are used for abutting against two adjacent workpieces to be welded respectively.

2. The robot for automatic spot welding of metal furniture according to claim 1, characterized in that: the spot welding robot further comprises a supporting device and a spot welding robot main body; the fixed end of the second positioning mechanism, the fixed end of the spot welding robot main body and the three groups of first positioning mechanisms are fixedly arranged on the supporting device; the spot welding robot main body is used for welding two adjacent workpieces to be welded.

3. The robot for automatic spot welding of metal furniture according to claim 2, characterized in that: the first positioning mechanism comprises a first positioning block and a first mounting block; the first mounting block is provided with at least one block, and the upper surface and the lower surface of the first mounting block are respectively and fixedly connected with the bottom surface of the first positioning block and the top surface of the supporting device; the first positioning block is provided with two positioning surfaces for positioning.

4. A robot for automatic spot welding of metal furniture according to claim 3, characterized in that: the cross section of the first positioning block is V-shaped.

5. The robot for automatic spot welding of metal furniture according to claim 2, characterized in that: the second positioning mechanism comprises a second driving unit and a push block; the fixed end of the second driving unit is fixedly arranged on the supporting device; the second driving unit is in linkage connection with the push block so as to enable the push block to move, and therefore the workpiece to be welded is fixed.

6. A robot for automatic spot welding of metal furniture according to claim 5, characterized in that: the driving unit comprises a cylinder; the cylinder is installed on the supporting device, and the telescopic end of the cylinder is fixedly connected with the push block.

7. A robot for automatic spot welding of metal furniture according to claim 5, characterized in that: the second positioning mechanism further comprises a guide assembly; the guide assembly is arranged on the supporting device and used for guiding the push block.

8. A robot for automatic spot welding of metal furniture according to claim 7, characterized in that: the guide assembly comprises two pins; the two pins are embedded on the supporting device and are respectively positioned at the left end and the right end of the push block.

9. The robot for automatic spot welding of metal furniture according to claim 2, characterized in that: the supporting device comprises a base, a rotating mechanism and a turntable; the rotating mechanism is provided with a rotatable movable end; the movable end of the rotating mechanism is fixedly connected with the turntable, and the fixed end of the rotating mechanism is fixedly connected with the base; the fixed end of the spot welding robot main body is fixedly arranged on the base and is positioned on the outer side of the rotary table; the fixed end of the second positioning mechanism and the three groups of first positioning mechanisms are fixedly arranged on the turntable; the rotating mechanism drives the turntable and all the workpieces to rotate by a preset angle, so that the spot welding robot main body can weld two adjacent workpieces to be welded.

10. A robot for automatic spot welding of metal furniture according to claim 9, characterized in that: the rotating mechanism comprises a first driving unit and a worm gear reducer; the first driving unit and the worm gear reducer are both arranged on the base, and the first driving unit is in linkage connection with the worm gear reducer; and the output shaft of the worm gear reducer is fixedly connected with the turntable so as to enable the turntable to rotate.