CN108451171B

CN108451171B - Rotary changeable round table

Info

Publication number: CN108451171B
Application number: CN201810505681.5A
Authority: CN
Inventors: 王德红
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-05-24
Filing date: 2018-05-24
Publication date: 2023-07-28
Anticipated expiration: 2038-05-24
Also published as: CN108451171A

Abstract

The invention relates to a rotary changeable round table, which comprises a table top and table legs, and is characterized in that: the desktop comprises a round desk plate, a round bottom plate, an even number of fan-shaped desk plates and a folding device for folding and unfolding the fan-shaped desk plates; the circular table plates are arranged on the circular bottom plate in parallel, the even number of the fan-shaped table plates are uniformly arranged between the circular table plates and the circular bottom plate, the even number of the fan-shaped table plates are folded to form two layers of staggered and laminated fan-shaped table plates, the even number of the fan-shaped table plates are unfolded and spliced to form a complete circular ring fan-shaped table plate, the fan-shaped table plates are fixedly arranged on the circular bottom plate through a folding device, the circular table plates are driven to be connected with a receiving device, and the fan-shaped table plates are controlled to be folded and unfolded by rotating the circular table plates. Reasonable in design, rotatory circular table can realize the size transform with the desktop, simple structure, and combination simple to operate, swift.

Description

Rotary changeable round table

Technical Field

The invention relates to the field of household, in particular to a rotary variable round table.

Background

At present, when a household takes meals at ordinary times, 3-5 persons are needed, only one fixed small round table is needed, but a round table with a large diameter and a small rotary table is needed for holidays or friends and relatives to get together. At present, only a large-diameter table plate and a small-diameter turntable can be purchased separately and placed on an original table for use, but the large-diameter table plate can be stored conveniently, particularly urban residents have limited living space, and even if the large-diameter table plate and the small-diameter turntable are placed in places, the indoor attractiveness can be influenced.

Patent application number 201510426717.7 provides a variable diameter folding dining table, can realize that many people take dinner simultaneously, but its structure is complicated, and the combination installation is difficult.

Disclosure of Invention

In order to solve the problems, the invention provides the rotary changeable round table which is reasonable in design, the size of the table top can be changed by rotating the round table plate, and the rotary changeable round table is simple in structure and convenient and quick to assemble and install.

The technical scheme of the invention is as follows:

the utility model provides a rotatory changeable round table, it includes desktop and table foot, its characterized in that: the desktop comprises a round desk plate, a round bottom plate, an even number of fan-shaped desk plates and a folding device for folding and unfolding the fan-shaped desk plates.

The circular table plates are arranged on the circular bottom plate in parallel, the even number of the fan-shaped table plates are uniformly arranged between the circular table plates and the circular bottom plate, the even number of the fan-shaped table plates are folded to form two layers of staggered and laminated fan-shaped table plates, the even number of the fan-shaped table plates are unfolded and spliced to form a complete circular ring fan-shaped table plate, the fan-shaped table plates are fixedly arranged on the circular bottom plate through a folding device, the circular table plates are driven to be connected with a receiving device, and the fan-shaped table plates are controlled to be folded and unfolded by rotating the circular table plates.

The folding device comprises a transmission rod, a fixed sliding rail, a lifting sliding frame, a rotating shaft, a transmission disc, a lifting disc and a bearing base, wherein the transmission disc, the lifting disc and the bearing base are arranged in parallel from top to bottom, the bearing base is fixedly arranged on a circular bottom plate, the rotating shaft is vertically and rotatably arranged on the bearing base through a bearing, the top of the rotating shaft sequentially passes through the lifting disc and the transmission disc, the top of the rotating shaft is connected with a circular table plate, a gap is reserved between the rotating shaft and the lifting disc, the rotating shaft is fixedly connected with the transmission disc, a plurality of stand columns are uniformly arranged on the outer side of the bearing base in a circle, the stand columns pass through the lifting disc, a linear bearing is arranged between the stand columns and the lifting disc, the linear bearing is fixedly arranged on the lifting disc, a spring is sleeved on the stand columns, two ends of the spring are respectively propped against the bearing base and the lifting disc, the fixed sliding rail is radially and fixedly arranged on the circular bottom plate, the lifting sliding carriage is radially and fixedly arranged on the circular bottom plate, the fixed sliding rail and the lifting carriage are respectively in one-to-one correspondence with the fan-shaped table plate, the fan-shaped table plate is respectively, the fan-shaped table plate is fixedly connected with the fixed sliding rail and the lifting carriage, a fixed sliding rail is respectively through the sliding block and the sliding block is hinged with the fan-shaped table plate, a plurality of the driving table is hinged with the transmission disc, a plurality of stand columns are synchronously arranged along the fixed sliding table, the sliding arms and the sliding table and the force arm is uniformly move along the fixed table and the force arm, the force arm is arranged along the top and the limit, and the force arm is arranged along the same as the top and the top is arranged.

The circular table plate is rotated, the circular table plate drives the rotating shaft to rotate, the driving disc is connected with the rotating shaft to rotate, the fan-shaped table plate is driven by the driving rod to outwards slide along the fixed sliding rail and the lifting sliding frame respectively, meanwhile, the force arm arranged on the rotating shaft rotates, the force arm upwards slides along the slope of the trapezoidal wedge block to push the lifting disc and the elastic force action of the spring is supposed, the lifting disc moves upwards, and the lifting disc drives the fan-shaped table plate on the lower layer to move upwards, so that the fan-shaped table plate is unfolded.

The circular table plate is rotated reversely, the circular table plate drives the rotating shaft to rotate reversely, the driving disc is connected with the rotating shaft to rotate reversely, the fan-shaped table plate is driven by the driving rod to slide inwards along the fixed sliding rail and the lifting sliding frame respectively, meanwhile, the force arm arranged on the rotating shaft rotates, the force arm slides downwards along the slope of the trapezoidal wedge block, the lifting disc presses the spring to move downwards under the action of dead weight, and the lifting disc drives the fan-shaped table plate on the lower layer to move downwards, so that the fan-shaped table plate is folded.

The technical scheme is further improved and refined, and the transmission disc and the lifting sliding frame are integrally cut and formed.

According to the technical scheme, the technical scheme is further improved and refined, the fact that the fan-shaped table plates have a certain thickness is considered, the spliced complete circular ring fan-shaped table plates cannot be folded directly, the fan-shaped table plates are required to be layered up and down, when the driving plate is designed to rotate to drive the fan-shaped table plates to be unfolded to the limit position, gaps are reserved between the fan-shaped table plates, the forward rotating driving plate drives the fan-shaped table plates folded to the limit position to be unfolded to the limit position first, then the driving plate is rotated to drive the fan-shaped table plates to be folded to the limit position first, the driving plate is rotated to drive the fan-shaped table plates to be folded to the limit position again, and accordingly the distance and time required by the vertical separation of the fan-shaped table plates are saved, and the size specification of the trapezoid wedge is set according to the lifting requirement of the lifting plate when the fan-shaped table plates are folded and unfolded, so that the folding is completed smoothly is ensured.

The technical scheme is further improved and refined, the clamping groove penetrating through the peripheral surface of the rotating shaft is formed in the top of the rotating shaft, the round groove is formed in the bottom of the round table plate, the spring positioning pin is arranged on the side wall of the round groove and penetrates through the side wall of the round groove to extend out of the round table plate, the round table plate is rotatably arranged on the rotating shaft through a bearing, the top of the rotating shaft extends into the round groove of the round table plate, the spring positioning pin extends into the round groove to be clamped with the clamping groove in the top of the rotating shaft, when the size of the table top needs to be adjusted, the spring positioning pin is pressed, the spring positioning pin is clamped in the clamping groove in the top of the rotating shaft, the table top can be adjusted by rotating the round table plate, after the adjustment is finished, the spring positioning pin is loosened, the spring positioning pin automatically resets, the round table plate is loosened, the round table plate is rotated under the action of the bearing, and the rotating shaft cannot rotate under the action of the driving disc and the fan-shaped table plate connected with the driving disc.

The technical scheme is further improved and refined, the clamping groove penetrating through the peripheral surface of the rotating shaft is formed in the top of the rotating shaft, the side coaming is sleeved on the round bottom plate, a plurality of clamping pins are uniformly arranged on the inner wall of the side coaming, inclined sliding grooves are formed in the periphery of the corresponding round bottom plate, pin grooves are formed in the upper side and the lower side of the sliding grooves respectively, the clamping pins are located in the inclined sliding grooves, the rotating side coaming slides along the sliding grooves, the clamping pins are located in the upper side pin grooves, the side coaming is propped against the round table plate, the round table plate is prevented from rotating, the clamping pins are located in the lower side pin grooves, the top of the side coaming is located below the lower fan-shaped table plate, the whole appearance of the round table is attractive, external sundries are prevented from entering, normal operation of the folding device is influenced, and a disassembling opening is further formed in the position of the clamping pins of the round bottom plate corresponding to the side coaming, and the side coaming is convenient to disassemble.

The technical scheme is further improved and refined, the chamfers are symmetrically arranged at the two corners of the inner side of the fan-shaped table plate positioned on the upper layer after the fan-shaped table plate is folded, the openings are symmetrically arranged at the two corners of the inner side of the fan-shaped table plate positioned on the lower layer after the fan-shaped table plate is folded, when the fan-shaped table plate is folded to the limiting position, the chamfers of the fan-shaped table plate positioned on the upper layer are mutually attached, the openings of the fan-shaped table plate positioned on the lower layer are spliced to form grooves, the grooves are clamped on the outer side of the sliding block of the fan-shaped table plate positioned on the upper layer, so that the fan-shaped table plate can be folded to the greatest extent, the upper limit of the length design of the fan-shaped table plate is improved, and the diameter of a large round table formed by unfolding the fan-shaped table plate is larger.

The technical scheme is further improved and refined, the side surfaces of two adjacent fan-shaped table plates of the complete circular ring fan-shaped table plate are correspondingly provided with the mutually meshed notch and the bulge, and the spliced complete circular ring fan-shaped table plate structure is firmer through the mutually meshed notch and bulge.

The technical scheme is further improved and refined, and a turntable balance wheel is arranged on the upper surface of the inner side of the fan-shaped table plate positioned on the upper layer after the fan-shaped table plate is folded, so that the circular table plate is supported to rotate stably.

The technical scheme is further improved and refined, the arm of force is sleeved with a bearing, and the bearing rolls along the slope of the trapezoidal wedge block.

The technical scheme is further improved and refined, and the buffer noise reduction pad is arranged at the bottom of the transmission disc, so that the buffer noise reduction effect is achieved.

Compared with the prior art, the rotary changeable round table is simple and convenient to operate, attractive and elegant, the table top can be changed into small by only operating the elastic locating pins and the rotary round table plate, when the table top is large, multiple people can take meals at the same time, and when the table top is small, the table top can be fully used in daily life of a family and occupies a small space; meanwhile, when the size is not required to be adjusted, the round table plate can be used in a rotating mode, and the round table plate is simple in structure and convenient to assemble and install.

Drawings

Fig. 1 is a schematic view of the structure of the rotary changeable round table when the table is folded.

Figure 2 is a schematic view of the structure of the rotary table when unfolded.

Figure 3 is a top view of the rotary table when extended.

Figure 4 is a schematic view of a circular table structure of a rotary variable round table.

Figure 5 is a partial top view of a rotary variable round table.

Figure 6 is a schematic view of a part of the structure of the folding device of the rotary changeable round table.

Figure 7 is a schematic view of a fan-shaped table being unfolded and folded.

Figure 8 is a graph of moment arm versus trapezoidal wedge for a rotary variable round table.

In the figure, a circular table 01 and a circular bottom plate 04 are provided with a fan-shaped table 02 folding device 03; the round table 01 is provided with a driving rod 05 in parallel, a sliding rail 06 is fixed, a sliding frame 07 is lifted, a rotating shaft 08 is lifted, a driving disc 09 is lifted, a bearing base 11, a column 12, a linear bearing 13, a spring 14, a trapezoidal wedge 15, a moment arm 16, a side wall 17, a bearing 18, a spring positioning pin 19, a round groove 20, a turntable balance wheel 21 and a buffering noise reduction pad 22.

Detailed Description

As shown in fig. 1-8, a rotary changeable round table comprises a table top and table legs, wherein the table top comprises a round table plate 01, a round bottom plate 04, an even number of fan-shaped table plates 02 and a folding device 03 for folding and unfolding the fan-shaped table plates 02; the round table boards 01 are arranged above the round bottom board 04 in parallel, even number of fan-shaped table boards 02 are uniformly arranged between the round table boards 01 and the round bottom board 04, the even number of fan-shaped table boards 04 are folded into two layers of staggered and laminated fan-shaped table boards, the even number of fan-shaped table boards 04 are unfolded and spliced into a complete round ring fan-shaped table board, the fan-shaped table boards 02 are fixedly arranged on the round bottom board 04 through a folding device, the round table boards 01 drive a connecting and receiving device 03, and the fan-shaped table boards 04 are controlled to be folded and unfolded by rotating the round table boards 01; the folding device 03 comprises a transmission rod 05, a fixed sliding rail 06, a lifting sliding frame 07, a rotating shaft 08, a transmission disc 09, a lifting disc 10 and a bearing base 11 which are arranged in parallel from top to bottom, wherein the bearing base 11 is fixedly arranged on a round bottom plate 04, the rotating shaft 08 is vertically and rotatably arranged on the bearing base 11 through a bearing, the top of the rotating shaft 08 sequentially passes through the lifting disc 10 and the transmission disc 09, the top of the rotating shaft 09 is connected with a round table 01, a gap is reserved between the rotating shaft 08 and the lifting disc 10, the rotating shaft 08 is fixedly connected with the transmission disc 09, a plurality of stand columns 12 are uniformly arranged on the periphery of the outer side of the bearing base 11, the stand columns 12 pass through the lifting disc 10, a linear bearing 13 is arranged between the stand columns 12 and the lifting disc 10, the linear bearing 13 is fixedly arranged on the lifting disc 10, springs 14 are sleeved on the stand columns 12, two ends of the springs 14 are respectively propped against the bearing base 11 and the lifting disc 10, the fixed slide rail 06 is radially and fixedly arranged on the circular bottom plate 04, the lifting sliding frame 07 is radially and fixedly arranged on the lifting disk 10, the fixed slide rail 06 and the lifting sliding frame 07 are mutually alternated, the fixed slide rail 06 and the lifting sliding frame 07 are respectively in one-to-one correspondence with the fan-shaped table boards 02, the fan-shaped table boards 02 are respectively connected with the fixed slide rail 06 and the lifting sliding frame 07 through sliding blocks in a sliding way, the fan-shaped table boards 02 are respectively hinged with the driving disk 09 through driving rods 05, the driving disk 09 is rotated, the driving rods 05 push the fan-shaped table boards 02 to synchronously move along the fixed slide rail 06 and the lifting sliding frame 07 for folding and unfolding, a plurality of trapezoidal wedges 15 are uniformly arranged at the bottom of the lifting disk 10 in one circle, a plurality of force arms 16 are arranged on the rotating shaft 08, the force arms 16 are in one-to-one correspondence with the trapezoidal wedges 15, the force arms 16 rotate along the rotating shaft, the force arms 16 slide along the slopes of the trapezoidal wedges 15 to push the lifting disk 10, the lifting disc 10 is positioned at the upper limit position, all the fan-shaped table boards 02 are positioned at the same horizontal plane, the lifting disc 10 is positioned at the lower limit position, and the fan-shaped table boards 02 are divided into an upper layer and a lower layer; considering that the fan-shaped table 02 has a certain thickness, the spliced complete ring fan-shaped table can not be folded directly, the fan-shaped table 02 needs to be layered up and down, when the fan-shaped table 02 is driven to be unfolded to the limit position by the rotation of the driving disc 09, a gap is reserved between the fan-shaped tables 02, so that the fan-shaped table folded to the limit position is firstly unfolded to the limit position by the forward rotation of the driving disc 09, the fan-shaped table can be spliced into the ring-shaped table only by the furling of the fan-shaped table by the forward rotation of the driving disc, the spliced ring-shaped fan-shaped table is firstly unfolded to the limit position by the backward rotation of the driving disc 09, the fan-shaped table is driven to be furled to the limit position by the furling of the driving disc, and the distance and time needed by the up-down separation of the fan-shaped table 02 are saved, and the size specification of the trapezoid wedge 14 is set according to the lifting requirement of the fan-shaped table when the fan-shaped table is furled and unfolded, and smooth completion of the furling is ensured; the top of the rotating shaft 08 is provided with a clamping groove penetrating through the peripheral surface of the rotating shaft, the bottom of the round table plate 01 is provided with a round groove 20, the side wall of the round groove is provided with a spring positioning pin 19, the spring positioning pin 19 penetrates through the side wall of the round groove and stretches out of the round table plate 01, the round table plate 01 is rotatably arranged on the rotating shaft 08 through a bearing, the top of the rotating shaft 08 stretches into the round groove 20 of the round table plate, the elastic positioning pin stretches into the round groove 20 to be clamped with the clamping groove at the top of the rotating shaft 08, when the size of a table top needs to be adjusted, the spring positioning pin 19 is pressed, the elastic positioning pin 19 is clamped in the clamping groove at the top of the rotating shaft 08, the size adjustment of the table top can be realized by rotating the round table plate, after the adjustment is finished, the elastic positioning pin is loosened, the elastic positioning pin automatically resets to loosen the round table plate 01, the round table plate 01 rotates around the rotating shaft 08 under the action of the bearing, and the rotating shaft 08 cannot rotate under the action of the driving disc 09 and the fan-shaped table plate 02 connected with the driving disc 09; the round bottom plate 01 is sleeved with the side coaming 17, a plurality of clamping pins are uniformly arranged on the inner wall of the side coaming 17, an inclined chute is arranged on the periphery of the corresponding round bottom plate, pin grooves are respectively arranged on the upper side and the lower side of the chute, the clamping pins are positioned in the inclined chute, the side coaming 17 rotates, the clamping pins slide along the chute, the clamping pins are positioned in the upper side pin grooves, the side coaming 17 is propped against the round table 01, the round table is prevented from rotating, the clamping pins are positioned in the lower side pin grooves, the top of the side coaming 17 is positioned below the lower layer fan-shaped table 02, a disassembling opening is further arranged on the periphery of the round bottom plate 04 corresponding to the clamping pins of the side coaming 17, the whole appearance of the round table is more attractive, and meanwhile, the entering of external sundries is prevented from being influenced, and the normal operation of the gathering device 03 is influenced; chamfer angles are symmetrically arranged at two corners of the inner side of the fan-shaped table plate 02 positioned on the upper layer after the fan-shaped table plate 02 is folded, openings are symmetrically arranged at two corners of the inner side of the fan-shaped table plate 02 positioned on the lower layer after the fan-shaped table plate 02 is folded to the limit position, the chamfer angles of the fan-shaped table plates on the upper layer are mutually attached, grooves are spliced between the openings of the fan-shaped table plates on the lower layer, the grooves are clamped on the outer side of the sliding block of the fan-shaped table plate on the upper layer, so that the fan-shaped table plate 02 can be folded to the greatest extent, the upper limit of the length design of the fan-shaped table plate 02 is improved, and the diameter of a large round table formed by unfolding the fan-shaped table plate 02 is larger; the side surfaces of two adjacent fan-shaped table plates of the complete ring fan-shaped table plate are correspondingly provided with mutually meshed notches and protrusions, and the spliced complete ring fan-shaped table plate structure is firmer through the mutually meshed notches and protrusions; the upper surface of the inner side of the fan-shaped table plate 02 positioned on the upper layer after being folded is provided with a turntable balance wheel for supporting the circular table plate to rotate stably; the arm 16 is sleeved with a bearing 18, and the bearing 18 rolls along the slope of the trapezoidal wedge; a buffering noise reduction pad 21 is arranged at the periphery of the bottom of the transmission disc.

Because of the limited text expression and the limitless specific structure, it is possible for those skilled in the art to make several improvements, modifications or changes without departing from the principles of the present invention, and to combine the above technical features in a suitable manner; such modifications, variations and combinations, or the direct application of the inventive concepts and aspects to other applications without modification, are contemplated as falling within the scope of the present invention.

Claims

1. The utility model provides a rotatory changeable round table, it includes desktop and table foot, its characterized in that: the desktop comprises a round desk plate, a round bottom plate, an even number of fan-shaped desk plates and a folding device for folding and unfolding the fan-shaped desk plates;

the circular table plates are arranged on the circular bottom plate in parallel, even number of fan-shaped table plates are uniformly arranged between the circular table plates and the circular bottom plate, the even number of fan-shaped table plates are folded into two layers of fan-shaped table plates which are stacked in a staggered mode, the even number of fan-shaped table plates are unfolded and spliced into a complete circular ring fan-shaped table plate, the fan-shaped table plates are fixedly arranged on the circular bottom plate through a folding device, the circular table plates drive a connecting and receiving device, and the fan-shaped table plates are controlled to be folded and unfolded by rotating the circular table plates;

the folding device comprises a transmission rod, a fixed sliding rail, a lifting sliding frame, a rotating shaft, a transmission disc, a lifting disc and a bearing base which are arranged in parallel from top to bottom, wherein the bearing base is fixedly arranged on a circular bottom plate, the rotating shaft is vertically and rotatably arranged on the bearing base through a bearing, the top of the rotating shaft sequentially penetrates through the lifting disc and the transmission disc, the top of the rotating shaft is connected with a circular table plate, a gap is reserved between the rotating shaft and the lifting disc, the rotating shaft is fixedly connected with the transmission disc, a plurality of stand columns are uniformly arranged on the outer side of the bearing base in a circle, the stand columns penetrate through the lifting disc, a linear bearing is arranged between the stand columns and the lifting disc, the linear bearing is fixedly arranged on the lifting disc, springs are sleeved on the stand columns, two ends of each spring are respectively propped against the bearing base and the lifting disc, the fixed sliding rail is radially and fixedly arranged on the circular bottom plate, the lifting sliding frame is radially and fixedly arranged on the lifting disc in a radial manner, the fixed sliding rails and the lifting sliding frame are mutually alternated, the fixed sliding rails and the lifting sliding frame are respectively in one-to-one correspondence with the fan-shaped table plates, the fan-shaped table plates are respectively connected with the fixed sliding rails and the lifting sliding frame through sliding blocks in a sliding manner, the fan-shaped table plates are respectively hinged with the driving disc through driving rods, the driving discs are rotated, the driving rods push the fan-shaped table plates to synchronously move along the fixed sliding rails and the lifting sliding frame to fold and unfold, a plurality of trapezoidal wedges are uniformly arranged on one circle of the bottom of the lifting disc, a plurality of force arms are arranged on a rotating shaft, the force arms are in one-to-one correspondence with the trapezoidal wedges, the force arms rotate along the slopes of the trapezoidal wedges, the trapezoidal wedges are pushed to push the lifting disc to move, the lifting disc is located at an upper limit position, all the fan-shaped table plates are located at the same horizontal plane, and the lifting disc is located at a lower limit position, and the fan-shaped table plates are divided into an upper layer and a lower layer;

the transmission disc and the lifting sliding frame are integrally cut and formed;

when the transmission disc rotates to drive the fan-shaped table plates to be unfolded to the limit position, gaps are reserved among the fan-shaped table plates, and the size specification of the trapezoid wedge blocks is set according to the lifting requirement of the lifting disc when the fan-shaped table plates are folded and unfolded;

the top of the rotating shaft is provided with a clamping groove penetrating through the peripheral surface of the rotating shaft, the bottom of the circular table plate is provided with a circular groove, the side wall of the circular groove is provided with a spring positioning pin, the spring positioning pin penetrates through the side wall of the circular groove to extend out of the circular table plate, the circular table plate is rotatably arranged on the rotating shaft through a bearing, and the top of the rotating shaft extends into the circular groove of the circular table plate;

the periphery of the round bottom plate is provided with an inclined chute, the round bottom plate is sleeved with a side coaming, the inner wall of the side coaming is uniformly provided with a plurality of clamping pins, the inclined chute corresponding to the periphery of the round bottom plate is respectively provided with pin grooves at the upper side and the lower side of the chute, the clamping pins are positioned in the inclined chute, the rotary side coaming slides along the chute, the clamping pins are positioned in the upper side pin grooves, the side coaming is propped against the round table plate, the round table plate is prevented from rotating, the clamping pins are positioned in the lower side pin grooves, the top of the side coaming is positioned below the lower layer fan-shaped table plate, the whole appearance of the round table is more attractive, meanwhile, the effect of blocking external sundries from entering and affecting the normal operation of the folding device is achieved, and the clamping pin positions corresponding to the side coaming at the periphery of the round bottom plate are also provided with a disassembly opening, so that the side coaming is convenient to disassemble;

chamfer angles are symmetrically arranged at two corners of the inner side of the fan-shaped table plate positioned on the upper layer after the folding, openings are symmetrically arranged at two corners of the inner side of the fan-shaped table plate positioned on the lower layer after the folding, when the folding is carried out to the limit position, the chamfer angles of the fan-shaped table plates on the upper layer are mutually attached, grooves are spliced between the openings of the fan-shaped table plates on the lower layer, and the grooves are clamped on the outer sides of the sliding blocks of the fan-shaped table plates on the upper layer;

locating pins are correspondingly arranged on the side surfaces of two adjacent fan-shaped table plates of the complete circular ring fan-shaped table plate;

a turntable balance wheel is arranged on the upper surface of the inner side of the fan-shaped table plate positioned on the upper layer after being folded;

the arm of force is sleeved with a bearing which rolls along the slope of the trapezoid wedge;

the bottom of the transmission disc is provided with a buffering noise reduction pad.