CN115784066B

CN115784066B - Lifting mechanism

Info

Publication number: CN115784066B
Application number: CN202310044659.6A
Authority: CN
Inventors: 周道; 张庆; 梁烁; 王飞; 周磊; 叶莹
Original assignee: Shanghai Guona Semiconductor Technology Co ltd
Current assignee: Shanghai Guona Semiconductor Technology Co ltd
Priority date: 2023-01-30
Filing date: 2023-01-30
Publication date: 2023-05-12
Anticipated expiration: 2043-01-30
Also published as: CN115784066A

Abstract

The invention discloses a lifting mechanism which comprises a lifting shaft, wherein the lifting shaft can rotate along the axis of the lifting shaft under the driving of a lifting driving piece. At least one winding wheel which rotates synchronously with the lifting shaft is sleeved on the lifting shaft, and each winding wheel is wound with a conductive belt. One end of the conductive belt is fixed on the winding wheel, and a cable in the conductive belt is connected with a rotor of the conductive slip ring at the end part of the lifting shaft. The rotor of the conductive slip ring rotates synchronously with the lifting shaft, and the electric wire on the stator of the conductive slip ring is connected with an external electric wire. Set up a guide way on the winding wheel, because the guide way is located between outer anchor ring and the shaft hole, conductive belt's tip is fixed in the guide way, and the preforming of fixed conductive belt can not outstanding outer anchor ring, guarantees that outer anchor ring is smooth to have not protruding, therefore when conductive belt winds around outer anchor ring, does not have the convex closure, and conductive belt can laminate on the outer anchor ring of winding wheel tightly, has improved conductive belt elevating movement's positioning accuracy.

Description

Lifting mechanism

Technical Field

The invention relates to the technical field of automatic material transmission in the semiconductor manufacturing industry, in particular to a lifting mechanism.

Background

The transfer of wafer cassettes (FOUPs) is a common step in the semiconductor processing industry and typically employs an automated material transfer system (AMHSAutomatic Material Handling System). The core part in the material automatic transmission system is a crown block (OHT, overheadHoist Transport), the crown block automatically grabs and conveys the wafer box from one base station (Loadport) to the other base station, manual intervention is not needed in the whole process, pollution of a human body to a clean room is avoided, and meanwhile, the production rate is greatly improved. After the crown block grabs the wafer cassette, the wafer cassette needs to be lifted into the crown block and positioned and clamped. The lifting mechanism is therefore an important component of the crown block.

The lifting mechanism lifts the wafer box through the lifting belt, one end of the lifting belt is connected with the grabbing mechanism which grabs the wafer box, the other end of the lifting belt is fixed on the winding wheel, the winding wheel is fixed on the lifting shaft, and when the lifting shaft rotates, the lifting belt winds or unwinds on the winding wheel to lift the wafer box. At present, the lifting belt mainly adopts the form of "conductive belt", and the lifting belt includes belt body and the inside wire of belt body, and the belt body is used for bearing the weight of snatching mechanism and wafer box, and the wire is used for supplying power and communicating for snatching mechanism, and the wire leads the electrical slip ring and connects.

However, in the existing lifting mechanism, since the conductive belt needs to be fixed on the winding wheel, and the wire needs to pass through the inside of the winding wheel, the winding wheel is usually set to be split type, and the conductive belt is directly wound on the winding wheel after being compressed. Because the conductive belt is harder in texture, the compaction block cannot tightly compact the conductive belt on the winding wheel, so that a bulge is formed at the compaction position, the bulge can seriously influence the coiling precision of the conductive belt during lifting movement, and the grabbing mechanism below cannot stably run. Meanwhile, the rotor end of the conductive slip ring needs to rotate synchronously with the lifting shaft, the conductive slip ring is a precise and fragile element, and the conductive slip ring can be damaged by adopting rigid connection between the lifting shaft and the rotor end. At present, the rotor end of the conductive slip ring and the lifting shaft are flexibly connected by the rubber ring, but the fixing effect of the rubber ring is poor, and the rotor end of the conductive slip ring and the lifting shaft are easy to have a rotating speed difference, so that the lead is pulled, and the service life of the lead is seriously influenced.

Disclosure of Invention

In order to overcome the defects, the invention aims to provide a lifting mechanism, and the lifting stability and precision are greatly improved.

In order to achieve the above purpose, the invention adopts the following technical scheme: a lifting mechanism, a lifting shaft, the lifting shaft can rotate along the self axis. The winding wheel is provided with at least one and cup joints on the lift axle with lift axle synchronous rotation, every the winding wheel all includes outer anchor ring, shaft hole, passageway one, passageway two and direction passageway, the shaft hole supplies the lift axle to pass, the direction passageway is located between shaft hole and the outer anchor ring and encircles the shaft hole setting, the direction passageway intercommunication runs through outer anchor ring's passageway one, passageway two sets up between direction passageway and shaft hole and communicates both. The conductive slip ring is arranged at the end part of the lifting shaft, and the rotor end of the conductive slip ring is fixed with the lifting shaft and synchronously rotates.

The invention has the beneficial effects that: set up a guide way on the winding wheel, because the guide way is located between outer anchor ring and the shaft hole, the lifting belt of being convenient for is fixed, and the preforming of fixed lifting belt can not outstanding outer anchor ring, guarantees that outer anchor ring is smooth to have not protruding, consequently when the lifting belt is rolled up at outer anchor ring, does not have the convex closure, and the lifting belt can laminate on the outer anchor ring of winding wheel tightly, has guaranteed lifting belt elevating movement's positioning accuracy.

Further, the device also comprises a lifting belt which is wound on the outer ring surface, and the lifting belt is arranged at the inner end part of the guide channel in a penetrating way and is fixed in the guide channel. The lifting belt is a conductive belt, and a cable in the conductive belt enters the shaft hole from the second channel, penetrates out of the winding wheel and the lifting shaft, and is connected with the rotor end. The guide channel and the channel II are convenient for the cable to be routed, and the cable is effectively protected.

Further, the first channel is arranged along the radial direction of the winding wheel, one side of the first channel, which is close to the outer ring surface, is provided with an inlet of the conductive belt, and a chamfer angle with an arc-shaped structure is formed between the side wall of the first channel at the inlet and the outer ring surface. Because the conductive belt has certain thickness, if direct 90 degrees bend, the conductive belt can not press close to the department of bending, consequently sets up an arc chamfer, lets conductive belt closely laminate in the juncture of outer annular face and passageway one, and then makes conductive belt can closely laminate on the winding wheel outer annular face.

Further, the first channel is provided with at least one inclined plane or cambered surface, and the conductive belt is attached to the inclined plane or cambered surface and enters the guide channel. The inclined plane or the cambered surface is arranged to form a structure that the space of the first channel is gradually increased from the inlet of the first channel, namely the cross section area of the first channel is gradually increased from the position close to the outer annular surface to the position far from the outer annular surface. On one hand, the structure reserves enough space for the conductive belt to enter the guide channel from the channel I, on the other hand, the inclined plane or the circular arc faces the conductive belt to guide, so that smooth transition from the channel I to the entrance of the guide channel is realized, the conductive belt is tightly attached to the inclined plane or the circular arc face, the conductive belt is prevented from swelling at the turning part, and the conductive belt is ensured to be flat in the channel I.

Further, the guide channel surrounds the entire shaft hole or part of the shaft hole.

When the guide channel surrounds the whole shaft hole, the guide channel is of an end-to-end structure, at the moment, the central lines of the second channel and the first channel are coincident, and the second channel and the first channel are arranged along the same radial direction. When the channel surrounds part of the shaft hole, namely, a space is reserved between the inlet and the outlet of the guide channel, the guide channel is not connected end to end, and the second channel is arranged at the outlet of the guide channel.

Further, the winding wheel comprises two end faces located on two sides of the outer ring face, each end face is provided with a channel along the axial direction, the channels are arranged on the corresponding end faces at intervals along the circumferential direction, the channels on the two end faces are arranged in a staggered mode, and the channels on one end face can be communicated with the adjacent two channels on the other end face.

The channels on the two end faces are staggered, so that a large amount of hollowing treatment is only needed for the internal material of the winding wheel, a guide channel which can be processed to form an end-to-end structure is ensured, and even if a guide channel is arranged between the outer annular surface and the shaft hole, the winding wheel is still integrated, so that the feasibility of element machining is ensured. Meanwhile, the integral structure ensures the strength and rigidity of the winding wheel. Furthermore, the alternating channels, which define the conductive belt between the two end faces, do not slip out of the winding wheel from either end face, defining the axial position of the conductive belt within the guide channel.

Further, the winding wheel comprises a winding part and fixing parts located on two sides of the winding part along the axial direction, the winding part and the fixing parts are of coaxial cylindrical structures, the diameter of the winding part is larger than that of the fixing parts, the side surfaces of the winding part are outer ring surfaces, the surfaces, away from the winding part, of the two fixing parts are end surfaces provided with a channel, and the channel extends to the winding part.

Further, the end part of the conductive belt is fixed in the guide channel through a pressing sheet, a notch communicated with the guide channel is further formed in the side wall of the fixing part in the radial direction, a bolt hole corresponding to the notch is formed in the fixing part, and the pressing sheet is fixed with the fixing part through a bolt in threaded connection with the bolt hole. After the pressing sheet presses the conductive belt, the bolts are placed and screwed from the notches, and at the moment, the pressing sheet is fixed with the fixing part through the bolts penetrating through the bolt holes, namely, the end parts of the conductive belt are fixed in the guide channels. The notch is convenient for rotate the bolt, for installation and dismantlement convenience.

Furthermore, each winding wheel is fixedly provided with a baffle plate positioned on two sides of the outer ring surface, the baffle plates are of annular structures and are coaxially arranged with the winding wheel, the baffle plates extend out of the winding wheel, and a cavity for winding the conductive belt is defined between the two baffle plates and the outer ring surface. The baffle defines an axial position of the conductive belt on the outer annular surface, and reduces axial deflection of the conductive belt during winding.

Further, an inclined wedge surface is arranged on one side of the baffle plate, facing the outer annular surface, and is arranged on the part, extending out of the winding wheel, of the baffle plate, and each wedge surface flares outwards from one side, close to the outer annular surface, to one side, far away from the outer annular surface. The wedge-shaped surface enables the cavity to form a flaring structure, damage to the side edge of the conductive belt is reduced, and the service life of the conductive belt is prolonged.

Furthermore, the baffle is of a split structure and comprises at least two split parts, each split part is detachably connected with the winding wheel, and the split parts can be spliced to form the baffle of an annular structure. The pressing sheet can be removed from the guide channel after the baffle sheet is removed, and the conductive belt is taken out. The separation blade of split structure can be directly taken off the separation blade from the winding wheel under the prerequisite that other parts on the lift axle, such as bearing frame or electrically conductive sliding ring are motionless, is convenient for change electrically conductive belt.

Furthermore, a wiring groove is formed in the side wall of the lifting shaft along the axis, when the lifting shaft is in key joint with the winding wheel, the position of the wiring groove corresponds to a second channel, and a cable penetrating out of the second channel is connected to the rotor end of the conductive slip ring along the wiring groove. The wire slot guides the cable, thus playing a role in fixation. And the wiring groove is formed in the side wall of the lifting shaft, is not provided with a hole in the center, is convenient for later maintenance and is also convenient for cable threading.

Further, the rotor end is connected with the lifting shaft through a connecting component, the connecting component comprises a connecting piece and a fixing piece, the connecting piece is fixed at the end part of the lifting shaft, and the fixing piece is used for connecting the rotor end with the connecting piece and realizing synchronous rotation of the rotor end and the connecting piece. The fixing piece is used for flexibly connecting the rotor end with the connecting piece.

Further, the connecting piece comprises a round connecting plate and an annular vertical wall extending along the side surface of the connecting plate, the connecting plate is fixed with the end part of the lifting shaft, an inserting cavity for inserting a rotor end is defined between the connecting plate and the annular vertical wall, and the rotor end is inserted in the inserting cavity in a suspending manner; the part of the fixing piece located in the inserting cavity is tensioned to be a limiting plane attached to the plane of the rotor end, the rotor end is located in a limiting cavity defined by the limiting plane and synchronously rotates with the limiting cavity under the pushing of the limiting plane, and the end part of the fixing piece penetrates through the limiting groove and is fixed on the outer wall of the annular vertical wall. The rotor end is of a non-circular structure, so that a limiting cavity flexibly clamped with the rotor end is formed by penetrating the fixing piece, and the fixing piece and the connecting piece are driven to synchronously rotate when synchronously rotating.

Furthermore, the fixing piece is a belt body made of metal or plastic, and the annular vertical wall is provided with a yielding groove for the end part of the belt body to pass through. The thickness of the belt body is thin, which is convenient for bending.

Further, each conductive belt corresponds to one steering wheel, and the conductive belt horizontally extending on the winding wheel is turned to be vertical after passing through the steering wheel. And a pair of follow-up wheels with adjustable intervals are arranged below each steering wheel, and are respectively positioned at two sides of the conductive belt and abutted against the side edges of the conductive belt. The conductive belt can move along the axial direction of the lifting shaft in the lifting movement process, if the conductive belt is limited by the baffle plate in the axial direction, the side edge of the conductive belt can generate sliding friction with the baffle plate, and the service life of the belt and the cleanliness of the cleaning room are influenced. Therefore, a pair of follow-up wheels is added, the follow-up wheels rotate along with the lifting of the conductive belt when the conductive belt is in operation, the axial position of the conductive belt is restrained, meanwhile, sliding friction between the conductive belt and the baffle plate or the flange is converted into rolling friction between the conductive belt and the follow-up wheels, and abrasion of the conductive belt is greatly slowed down.

Further, a guiding ring groove for embedding the side edge of the conductive belt is formed in the circumferential direction of the follower wheel, and the side edge of the conductive belt is always positioned in the guiding ring groove.

Drawings

FIG. 1 is a bottom view of an embodiment of the present invention;

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1 and a partial enlarged view thereof;

FIG. 3 is a perspective view of the substrate removed in accordance with an embodiment of the present invention;

FIG. 4 is a perspective view of a winding wheel in an embodiment of the invention;

FIG. 5 is another angular perspective view of a winding wheel according to an embodiment of the present invention;

FIG. 6 is a cross-sectional view of a winding wheel taken along a central plane in an embodiment of the present invention;

FIG. 7 is a front view of a winding wheel in an embodiment of the invention;

FIG. 8 is a perspective view showing a connection state of a connection assembly and a conductive slip ring according to an embodiment of the present invention;

FIG. 9 is a cross-sectional view of a connection assembly and conductive slip ring according to an embodiment of the present invention;

FIG. 10 is a schematic perspective view of a connector according to an embodiment of the present invention;

FIG. 11 is a schematic perspective view of a lifting shaft according to an embodiment of the present invention;

FIG. 12 is a schematic perspective view of a baffle according to an embodiment of the present invention;

fig. 13 is a schematic diagram showing a connection state of a pair of follower wheels and a conductive belt in an embodiment of the present invention.

In the figure:

1. a lifting shaft; 1a, wiring grooves; 2. a winding wheel; 21. a winding part; 211. an outer annulus; 22. a fixing part; 221. an end face; 224. a notch; 225. bolt holes; 23. a shaft hole; 24. a guide channel; 241. a first channel; 242. a second channel; 25. a first channel; 251. chamfering; 252. an inclined plane; 26. a second channel; 3. a conductive belt; 4. a conductive slip ring; 41. a rotor end; 5. a baffle; 51. a wedge surface; 6. a connection assembly; 61. a connecting piece; 611. a connecting plate; 6111. a wire hole; 6112. a connection hole; 612. an annular standing wall; 6121. a relief groove; 62. a fixing member; 621. a limit plane; 7. a substrate; 71. a bearing seat; 72. a mounting bracket; 8. a steering wheel; 9. a follower wheel; 91. a guide ring groove; 10. a transition wheel; 11. a synchronous pulley; 12. and a lifting shaft connecting piece.

Detailed Description

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making clear and defining the scope of the present invention.

Referring to fig. 1 to 3, a lifting mechanism of the present invention includes a lifting shaft 1, and the lifting shaft 1 can rotate along its own axis under the drive of a lifting driving member. The lifting shaft 1 is sleeved with at least one winding wheel 2 which rotates synchronously with the lifting shaft, and each winding wheel 2 is wound with a lifting belt, and in the embodiment, the lifting belt is a conductive belt 3. One end of the conductive belt 3 is fixed on the winding wheel 2, and a cable in the conductive belt 3 is connected with a rotor end 41 of the conductive slip ring 4 at the end of the lifting shaft 1. The rotor end 41 of the conductive slip ring 4 rotates synchronously with the lifting shaft 1, and the electric wire on the stator end of the conductive slip ring 4 is connected with an external electric wire.

When the lifting driving piece drives the lifting shaft 1 to rotate, the winding wheel 2 synchronously rotates, so that the conductive belt 3 is driven to be wound and unwound, and lifting of a clamping mechanism (not shown in the figure) connected with the other end of the conductive belt 3 is realized.

Referring to fig. 4 to 6, the winding wheel 2 includes an outer circumferential surface 211 for winding the conductive belt 3 and a shaft hole 23 for passing the lifting shaft 1, and the shaft hole 23 is axially formed along the winding wheel 2 and is coaxially disposed with the outer circumferential surface 211. The winding wheel 2 is also provided with a guide channel 24 which is arranged between the shaft hole 23 and the outer ring surface 211 and surrounds the shaft hole 23, the conductive belt 3 is arranged in the guide channel 24 in a penetrating way, and the end part of the conductive belt 3 is fixed in the guide channel 24. The guide channel 24 is communicated with a channel one 25 penetrating the outer ring surface 211, namely the channel one 25 is communicated with the outer ring surface 211 and the guide channel 24, and a channel two 26 communicated with the guide channel 24 and the shaft hole 23 is arranged between the guide channel and the shaft hole 23.

The guide channel 24 is arranged on the winding wheel 2, the end part of the conductive belt 3 is fixed in the guide channel 24 because the guide channel 24 is positioned between the outer annular surface 211 and the shaft hole 23, the pressing sheet for fixing the conductive belt 3 can not protrude out of the outer annular surface 211, and the outer annular surface 211 is ensured to be smooth and free of bulges, so that when the conductive belt 3 is wound on the outer annular surface 211, no convex hull exists, the conductive belt 3 can be tightly attached to the outer annular surface 211 of the winding wheel 2, and the positioning precision of the lifting movement of the conductive belt 3 is ensured. The lifting belt is not the conductive belt 3, but other conventional belts, and by adopting the winding wheel 2 structure in the application, the end part of the lifting belt can be fixed in the guide channel 24 through the arrangement of the guide channel 24, so that the lifting belt can be ensured not to have bulges on the outer ring surface 211, and the lifting precision is improved.

With respect to the conductive belt 3, the conductive belt 3 enters the guide passage 24 from the first passage 25, moves along the guide passage 24 and fixes the end portion thereof in the guide passage 24, and the cable in the conductive belt 3 continues to move along the guide passage 24 and enters the shaft hole 23 from the second passage 26, and passes out of the winding wheel 2 from between the winding wheel 2 and the lifting shaft 1. The cooperation of the guide channel 24 and the channel two 26 facilitates the threading of the cable of the conductive belt 3.

In one embodiment, referring to fig. 4 and fig. 7, the first channel 25 is disposed along the radial direction of the winding wheel 2, one side of the first channel 25 near the outer ring surface is an inlet of the conductive belt 3, a chamfer 251 with an arc structure is formed between the side wall of the first channel 25 at the inlet and the outer ring surface 211, and the chamfer 251 can enable the conductive belt 3 to be closely attached to the junction of the outer ring surface 211 and the first channel 25. Because the conductive belt 3 has a certain thickness, if the conductive belt 3 is bent directly by 90 degrees, the conductive belt 3 cannot be close to the bent position, and therefore, a chamfer 251 is provided, so that the conductive belt 3 can be tightly attached to the outer ring surface 211 of the winding wheel 2.

The inlet directions of the first channel 25 and the guide channel 24 are different, and the conductive belt 3 is turned into the guide channel 24 after entering the first channel 25, so, referring to fig. 6 and 7, the first channel 25 has a slope 252 or an arc surface, and the conductive belt 3 is attached to the slope 252 or the arc surface to enter the guide channel 24. The slope 252 or the cambered surface forms a structure that the space of the first channel 25 gradually increases from the inlet of the first channel, that is, the cross-sectional area of the first channel 25 gradually increases from the position close to the outer annular surface 211 to the position far from the outer annular surface 211. On one hand, the structure provides enough space for the conductive belt 3 to enter the guide channel 24 from the channel I25, on the other hand, the inclined plane 252 or the circular arc faces the conductive belt 3 to guide, so that smooth transition from the channel I25 to the inlet of the guide channel 24 is realized, the conductive belt 3 is tightly attached to the inclined plane 252 or the circular arc face, the conductive belt 3 is prevented from swelling at the turning part, and the conductive belt 3 is ensured to be flat in the channel I25.

Referring to fig. 6 and 7, the first passage 25 has a slope 252, and the slope 252 is inclined from the inlet of the first passage 25 toward the inlet of the guide passage 24 in the direction in which the conductive belt 3 is threaded. And the arc surface is a convex arc protruding toward the first channel 25.

Of course, in one embodiment, the first channel 25 may also have two inclined planes 252 or cambered surfaces, and the two inclined planes 252 or cambered surfaces are symmetrically disposed relative to the axis of the first channel, so that the first channel 25 may still form a structure with gradually increased space from the inlet of the first channel, and the conductive belt 3 is attached to one of the inclined planes 252 or cambered surfaces to enter the guiding channel 24. So long as the channel one 25 is guaranteed to have at least one inclined surface 252 or cambered surface for guiding the conductive belt 3.

In one embodiment, and referring to FIG. 6, the guide channel 24 surrounds the entire shaft bore 23, i.e., the guide channel 24 is in an end-to-end configuration. The arrow direction in fig. 6 is the direction of the cable in the conductive belt 3, and the conductive belt 3 is also along the arrow direction in fig. 6, but the conductive belt 3 does not need to be threaded in the entire guide channel 24, the conductive belt 3 is fixed at a position close to the channel two 26, and the cable continues to be threaded along the guide channel 24 until the cable passes through the entire guide channel 24, reaches the position of the channel two 26, and enters the channel two 26. At this time, the center lines of the second channel 26 and the first channel 25 are coincident, and the second channel 26 and the first channel 25 are opened along the same radial direction.

In this embodiment, the guide channel 24 has a radial cross section in the form of a circular ring, which is coaxial with the outer annular surface 211. The guide channel 24 of the circular ring structure facilitates the threading of the conductive belt 3. Of course, in some embodiments, the radial cross-section of the guide channel 24 is a polygonal structure with rounded corners at the junction of adjacent sides of the polygonal structure. In view of convenience in processing and threading the conductive belt 3, the guide channel 24 is generally selected from a circular ring structure and a quadrilateral structure, and as shown in fig. 6, the guide channel 24 is in a quadrilateral structure in this embodiment.

In one embodiment, the guide channel 24 surrounds a portion of the shaft bore 23, i.e., a space is left between the inlet and the outlet of the guide channel 24, the guide channel 24 is not connected end to end, and the second channel 26 is disposed at the outlet of the guide channel 24. At this time, the conductive belt enters from the inlet of the first channel 25, passes through the guide channel 24, is fixed between the inlet and the outlet of the guide channel 24, and the cable continues to pass through the guide channel 24 until the cable enters the second channel 26.

In this embodiment, the guide passage 24 has an arc-shaped structure in a radial cross section, and the arc-shaped structure has an arc whose center coincides with the center of the outer annular surface 211.

Of course, when the guide passage 24 surrounds the entire shaft hole 23, the distance of the guide passage 24 is large, and the contact area of the conductive belt 3 with the guide passage 24 is also increased, so that the connection of the conductive belt 3 with the winding wheel 2 is more stable.

Referring to fig. 4 and 5, the winding wheel 2 includes two end surfaces 221, the two end surfaces 221 are respectively located at two sides of the outer ring surface 211, each end surface 221 is provided with channels arranged at intervals along the axial direction, the channels on one end surface 221 do not penetrate the other end surface 221, and the channels are arranged at intervals along the circumferential direction on the corresponding end surface 221. The channels on both end faces 221 are staggered and the channels on one end face 221 can conduct adjacent channels on the other end face 221.

The two end surfaces 221 are a first end surface and a second end surface, as shown in fig. 5, the first end surface is provided with a first channel 241, as shown in fig. 5, the second end surface is provided with a second channel 242, the first channels 241 are arranged at intervals, the second channels 242 are arranged at intervals, and the second channels 242 are staggered with the first channels 241, i.e. the second channels 242 are positioned between two adjacent first channels 241. And referring to fig. 7, two ends of the second channel 242 are in communication with ends of two adjacent first channels 241, i.e. two adjacent first channels 241 are in communication through the second channel 242. The first channel 241 and the second channel 242 cooperate to form a guide channel 24 in the central plane of the winding wheel 2.

The channels on the two end faces 221 are staggered, and only a great deal of hollowing treatment is needed for the internal material of the winding wheel 2, so that the guide channel 24 which can be processed to form an end-to-end structure is ensured, and even if one guide channel 24 is arranged between the outer ring surface 211 and the shaft hole 23, the winding wheel 2 is still an integral body, so that the feasibility of element machining is ensured. At the same time, the integral structure ensures the strength and rigidity of the winding wheel 2. Furthermore, the alternating channels, which define the conductive belt 3 between the two end faces 221, do not slide out of the winding wheel 2 from either end face 221, define the axial position of the conductive belt 3 within the guide channel 24.

Referring to fig. 5, the winding wheel 2 includes a winding part 21 and fixing parts 22 located at both sides of the winding part 21 in an axial direction, the winding part 21 and the fixing parts 22 are of a cylindrical structure coaxially disposed, and the winding part 21 has a diameter larger than that of the fixing parts 22, and a shaft hole penetrates the winding part 21 and the two fixing parts 22. The side surface of the winding portion 21 is an outer ring surface 211 for winding the conductive belt 3, the two surfaces of the two fixing portions 22 away from the winding portion 21 are end surfaces 221 provided with channels, the channels are formed in the fixing portions 22 and can extend into the winding portion 21, and the conductive belt 3 passes through the guide channels 24 in the winding portion 21.

The end of the conductive belt 3 is fixed in the guide channel 24 by the pressing piece, and the pressing piece is also positioned in the guide channel 24, and the pressing piece does not protrude out of the outer ring surface 211, so that the winding of the conductive belt 3 is prevented from being influenced. The pressing sheet is fixed in the guide channel 24 by bolts, in order to facilitate placement of the pressing sheet, as shown in fig. 4 and 5, a notch 224 communicated with the guide channel 24 is further formed on the side wall of the two fixing portions 22 along the radial direction, and a bolt hole 225 corresponding to the notch 224 is formed on the fixing portion 22. The presser pieces are placed at the corresponding positions at the notches 224, at which time the presser pieces are fixed to the fixing portions 22 by bolts passing through the bolt holes 225, and the notches 224 facilitate the fixation and removal of the bolts to fix the ends of the conductive belt 3 in the guide channels 24. The pressing piece is positioned at the place where the first channel 241 and the second channel 242 are communicated, the pressing piece is placed at the corresponding position of the notch 224, the pressing piece placed at the notch 224 can extend from the first channel 241 to the second channel 242, and the conductive belt 3 is fixed from two sides.

The winding wheel 2 is connected with the lifting shaft 1 through keys so that the winding wheel 2 and the lifting shaft synchronously rotate, the lifting shaft 1 is provided with a flat key protruding out of the surface of the lifting shaft, and the winding wheel 2 is provided with a key slot which is communicated with the shaft hole and is used for embedding the flat key.

In one embodiment, in order to ensure that the conductive belt 3 is always located on the outer ring surface 211 during the rotation of the winding wheel 2 and does not generate axial offset during the winding process, as shown in fig. 2, two sides of each winding wheel 2 are respectively provided with a baffle 5 fixedly connected with the same, and the conductive belt 3 wound on the outer ring surface 211 of the winding wheel 2 is located between the two baffle 5.

Referring to fig. 12, the baffle 5 has an annular structure, the baffle 5 is coaxial with the winding wheel 2, the outer diameter of the baffle 5 is larger than that of the winding part 21, the baffle 5 is ensured to protrude out of the outer ring surface 211, and a cavity for winding the conductive belt 3 is defined between the two baffle 5 and the outer ring surface 211. The baffle 5 is sleeved on the fixing part 22 and is connected with the winding part 21 through bolts.

In order to allow the conductive belt 3 to be wound around the outer circumferential surface 211, the width of the outer circumferential surface 211 is not smaller than the width of the conductive belt 3. In order to improve stability and reduce offset, the width of the outer annular surface 211 is set to be the same as the width of the conductive belt 3. However, in order to avoid damage to the side edges of the conductive belt 3 by the edges of the flaps 5, the side of the flaps 5 facing the outer annular surface 211 is provided with an inclined wedge-shaped surface 51, see fig. 12, which wedge-shaped surface 51 is located on the opposite side of the two flaps 5 when the two flaps 5 are mounted on the winding wheel 2. Each wedge 51 flares outwardly from a side adjacent the outer annulus 211 to a side remote from the outer annulus 211, as shown in figure 2, the wedge 51 allowing the cavity to form a flared structure to reduce damage to the sides of the conductive strap 3.

When the conductive belt 3 is lifted and lowered, sliding friction is easily generated between the conductive belt 3 and the baffle plates 5 on two sides of the winding wheel 2, and the side surface of the conductive belt 3 is worn after long-time running, so that the bearing capacity of the conductive belt 3 is affected, and particles generated by wear damage the clean room environment. The wedge-shaped surface 51 on the baffle plate 5 reduces the contact between the baffle plate 5 and the side surface of the conductive belt 3, reduces the abrasion of the conductive belt 3, and prolongs the service life of the conductive belt 3.

As shown in fig. 2 and 12, the wedge-shaped surface 51 is provided at the portion of the flap 5 extending beyond the winding wheel 2, the other position of the side of the flap 5 facing the outer annular surface 211 remaining planar. Since the wedge-shaped surface 51 is only required at a portion which may be in contact with the conductive belt 3, and other positions are flat surfaces, the flat surfaces are closely attached to the side surfaces of the winding wheel 2, and the stability of the connection between the two surfaces is improved.

In one embodiment, the baffle 5 is a split structure, and includes at least two split parts, each of which is detachably connected to the winding wheel 2. The split parts can be spliced to form a complete baffle 5 with an annular structure. In this embodiment, the number of the split parts is two, namely a split part one and a split part two with fan-shaped structures, and the split part one and the split part two form a baffle 5 with annular structure when being combined, and after the conductive belt 3 is fixed on the winding wheel 2, the split part one and the split part two are respectively fixed on the winding wheel 2. Of course, the baffle 5 may be split into 3, 4 or more split parts. Only the baffle 5 is required to be separated, but for convenience of quick installation, see fig. 12, the separation parts are usually provided in two.

The tabs 5 are removed before the press sheet is removed from the guide channel 24 and the conductive belt 3 is removed. The separation blade 5 of the split structure can be directly taken down from the winding wheel 2 under the premise that other components on the lifting shaft 1, such as the bearing seat 71 or the conductive slip ring 4, are not moved, so that the conductive belt 3 is convenient to replace. The lifting mechanism is prevented from being integrally dismantled when the conductive belt 3 is replaced, and the maintenance is convenient.

In one embodiment, referring to fig. 11, the side wall of the lifting shaft 1 is provided with a wiring groove 1a along the axis, and the cable passing out of the second channel 26 is connected to the rotor end 41 of the conductive slip ring 4 along the wiring groove 1 a. The wiring groove 1a guides the cable and plays a role in fixation. The wiring groove 1a is formed in the side wall of the lifting shaft 1, and is not slotted in the center of the lifting shaft 1, so that wires can be directly threaded or cables can be replaced from the side surface, and later maintenance is facilitated.

When the lifting shaft 1 is in key joint with the winding wheel 2, the position of the wiring groove 1a corresponds to the second channel 26, the second channel 26 is communicated with the wiring groove 1a, and a cable penetrating out of the second channel 26 can directly enter the wiring groove 1 a.

Referring to fig. 3 and 8, the rotor end 41 of the conductive slip ring 4 is connected to the lifting shaft 1 through the connection assembly 6, and the rotor end 41 rotates in synchronization with the lifting shaft 1. The connecting assembly 6 includes a connecting member 61 and a fixing member 62, the connecting member 61 is fixed to the lifting shaft 1, and the fixing member 62 is used for flexibly connecting the rotor end 41 with the connecting member 61, and simultaneously synchronous rotation of the rotor end 41 and the connecting member 61 is achieved.

Referring to fig. 10, the connection member 61 is a cylindrical structure having one end opened, and includes a circular connection plate 611 and an annular standing wall 612 extending along a side surface of the connection plate 611, and the connection plate 611 is fixed to an end of the lifting shaft 1 by bolts. A plug-in cavity for inserting the rotor end 41 is defined between the connecting plate 611 and the annular standing wall 612, and the rotor end 41 is inserted in the plug-in cavity in a suspended manner. Because the rotor end 41 cannot be directly connected in a rigid manner, the rotor end 41 cannot be inserted into the insertion cavity in an interference manner, or cannot be directly fixed by bolts. Referring to fig. 9, a gap is left between the rotor end 41 and the annular standing wall 612, and the rotor end 41 is not in direct contact with the annular standing wall 612. The fixing piece 62 is located at the gap and extends out of the insertion cavity to be fixedly connected with the connecting piece 61, and the fixing piece 62 is used for driving the rotor end 41 and the connecting piece 61 to rotate synchronously.

The rotor end 41 is of a non-circular structure, the rotor end 41 is guaranteed to have a plane, as shown in fig. 9, the part of the fixing piece 62 located in the inserting cavity is tensioned to form a limiting plane 621 attached to the plane of the rotor end 41, the rotor end 41 is located in a limiting cavity defined by the limiting plane 621, the limiting cavity is in flexible clamping connection with the rotor end 41, and the limiting plane 621 pushes the rotor end 41 to rotate synchronously with the rotor end 41. The annular standing wall 612 is provided with a yielding groove 6121 for the end part of the fixing piece 62 to pass through, and the fixing piece 62 is fixed on the outer wall of the annular standing wall 612.

The fixing member 62 is a belt body made of metal or plastic, and the belt body is thin and is convenient to bend. In this application, the belt body is a steel belt.

In this embodiment, referring to fig. 9, the rotor end 41 has two parallel planes, which are circular arc surfaces and have a small gap (1 mm) with the annular standing wall 612. The part of the steel belt in the inserting cavity forms two parallel limiting planes 621, the two parallel surfaces of the limiting planes 621 and the rotor end 41 are contacted, the rotor end 41 is positioned between the two limiting planes 621, and the end part of the steel belt penetrates out of the inserting groove to be fixed with the connecting piece 61.

In this embodiment, as shown in fig. 10, the number of the relief grooves 6121 is four, each relief groove 6121 is axially formed along the annular standing wall 612, and the connecting lines of the four relief grooves 6121 form a square shape. The four abdication grooves 6121 are a groove one, a groove two, a groove three and a groove four in turn along the circumferential direction of the annular standing wall 612, as shown in fig. 9, the hollow arrow in the drawing is the penetrating direction of the steel belt, the steel belt enters the splicing cavity from the groove one, penetrates the splicing cavity from the groove two, winds on the outer wall of the annular standing wall 612 between the groove two and the groove three, then enters the splicing cavity from the groove three, penetrates the splicing cavity from the groove four, the two ends of the steel belt are overlapped on the outer wall of the annular standing wall 612 between the groove four and the groove one, and the steel belt is fixed by a bolt penetrating through the overlapped part of the end parts of the steel belt.

Of course, two steel belts can be adopted, one steel belt enters the plug-in cavity from the first groove and passes out of the plug-in cavity from the second groove, and then the two ends of the steel belt are fixed with the connecting piece 61 through bolts; the other steel strip enters the plug-in cavity from the third groove, passes out of the plug-in cavity from the fourth groove, and then is fixed with the connecting piece 61 at both ends.

The adapter is connected with the lifting shaft 1 through bolts, the rotor end 41 of the conductive slip ring 4 is inserted into the insertion cavity, the steel belt sequentially passes through the four abdicating grooves 6121, and is fixed on the annular vertical wall 612 through bolts after being wound on the annular vertical wall 612 for one circle. The flexible connection of the rotor end 41 and the lifting shaft 1 is realized, the installation requirement of the conductive slip ring 4 is met on one hand, the rotation synchronism of the rotor end 41 and the lifting shaft 1 is guaranteed on the other hand, the speed difference is reduced, the cable is prevented from being pulled, and the service life of the conductive slip ring 4 is effectively guaranteed.

Referring to fig. 10, the connecting plate 611 is provided with a wire hole 6111 through which the wire passes, and the position of the wire hole 6111 corresponds to the position of the wire groove 1a, and the wire groove 1a is provided on the side wall of the lifting shaft 1, so that the wire hole 6111 is also eccentrically arranged. The connection plate 611 is further provided with a connection hole 6112 through which a bolt passes, and the connection plate 611 is fixed to the lifting shaft 1 by the bolt passing through the connection hole 6112.

Referring to fig. 3, the winding wheel 2 is provided with three winding wheels respectively positioned at the middle position and two ends of the lifting shaft 1, so that three conductive belts 3 lift and lower the gripping device, and the lifting stability of the gripping device is improved.

In one embodiment, referring to fig. 3, the lifting shaft 1 is a split structure, that is, includes a lifting shaft a and a lifting shaft B, where the lifting shaft a and the lifting shaft B are connected by a lifting shaft connecting member 12, and the lifting shaft connecting member 12 connects the lifting shaft a and the lifting shaft B into a whole shaft, and at this time, the axes of the lifting shaft a and the lifting shaft B are coincident. Of course, the lifting shaft 1 can also adopt an integral structure, and a whole shaft can be directly adopted.

Referring to fig. 1-3, the lifting shaft 1 is further sleeved with a synchronous pulley 11 which rotates synchronously with the lifting shaft 1, the synchronous pulley 11 is connected with the lifting shaft 1 in a key manner, and the lifting driving piece transmits power to the synchronous pulley 11 through a synchronous belt so as to drive the lifting shaft 1 to rotate.

Referring to fig. 1 and 2, the lifting mechanism further comprises a base plate 7, and the lifting shaft 1 is rotatably connected to the base plate 7. The base plate 7 is fixed with a bearing seat 71, and the lifting shaft 1 is inserted into the bearing seat 71 and is rotatably connected with the bearing seat 71. In the present embodiment, two bearing seats 71 are provided to improve the stability of rotation of the lift shaft 1.

The lifting driving member is a motor and is fixed on the base plate 7. And the stator end of the conductive slip ring 4 is fixed on the base plate 7 through the mounting bracket 72, and the stator end of the conductive slip ring 4 is kept motionless.

Referring to fig. 3, when the lifting mechanism works, the base plate 7 is horizontally placed, the lifting shaft 1 is parallel to the base plate 7, and the same is horizontally placed, so that the conductive belt 3 needs to extend to different vertical planes to form a triangular structure, and then the triangular structure is connected with different positions of the grabbing mechanism. The triangular structure has high stability, and can improve the lifting stability of the grabbing mechanism. But three winding wheels 2 are sleeved on a lifting shaft, so that the winding wheels are positioned on the same vertical plane, and the part of the conductive belt 3 needs to be vertically turned after being horizontally extended for a certain distance, so that the horizontal direction is turned into the vertical direction to lift the grabbing mechanism. Therefore, the substrate 7 is provided with the steering wheel 8 which is arranged corresponding to the conductive belt 3, the steering wheel 8 is rotationally connected with the substrate 7, and the steering wheel 8 can rotate along the axis of the conductive belt 3 when the conductive belt 3 is lifted. The conductive belt 3 horizontally extending on the winding wheel 2 is turned to the vertical direction after passing through the turning wheel 8.

Flanges are provided along the peripheral surface at both ends of the steering wheel 8, and the conductive belt 3 is defined between the two flanges. The structure of the diverting pulley 8 can thus also define the axial position of the conductive belt 3.

In one embodiment, as shown in fig. 3, a pair of follower wheels 9 is further disposed under each of the steering wheels 8, and the pair of follower wheels 9 are respectively located on both sides of the conductive belt 3. The conductive belt 3 can move along the axial direction of the lifting shaft 1 in the lifting movement process, if the axial limiting is carried out only by virtue of the baffle plate 5 and the flange of the guide wheel, the side edge of the conductive belt 3 can generate sliding friction with the baffle plate 5 or the flange, and the service life of the belt and the cleanliness of the cleaning room are influenced. Each conductive belt 3 corresponds to a pair of follower wheels 9 positioned below the steering wheel 8, and when the conductive belt 3 operates, the follower wheels 9 rotate along with the lifting of the conductive belt 3, so that the axial position of the conductive belt 3 is restrained, and meanwhile, the sliding friction between the conductive belt 3 and the baffle 5 or the flange is converted into rolling friction between the conductive belt 3 and the follower wheels 9, so that the abrasion of the conductive belt 3 is greatly slowed down.

Referring to fig. 13, the follower wheel 9 is circumferentially provided with a guide ring groove 91 into which the side edge of the conductive belt 3 is fitted, and the side edge of the conductive belt 3 is always located in the guide ring groove 91. The guide ring groove 91 has a circular arc structure.

In one implementation, the spacing between the pair of follower wheels 9 is adjustable for ease of adjustment. The central shaft of each follower wheel 9 is fixed on a fixed block, and the two fixed blocks are jointly arranged on a fixed plate, and the fixed plate is fixed with the base plate 7. The positions of the two fixing blocks on the fixing plate are adjustable so as to adjust the distance between the two follower wheels 9. The fixed block is fixed with the fixed plate through the bolt, the waist-shaped hole through which the bolt passes is formed in the fixed block, the bolt can slide in the waist-shaped hole, and the position of the fixed block is adjusted and fixed through the cooperation of the waist-shaped hole and the bolt. The conductive belt 3 passes through the space between the pair of follower wheels 9, at the moment, the position of the fixed block is adjusted by loosening the bolts, and when the fixed block is moved to the optimal position, the bolts are locked in the waist-shaped holes, so that the positions of the follower wheels 9 are fixed.

For the conductive belt 3 which extends longer in the horizontal direction, the base plate 7 is also rotatably connected with a transition wheel 10, and the transition wheel 10 is arranged close to the winding wheel 2.

In the present embodiment, as shown in fig. 3, the conductive belts 3 on the winding wheels 2 located on the left and right sides extend too much in the horizontal direction, and therefore, one transition wheel 10 is provided at each of the winding wheels 2 near the left and right sides, and the conductive belts on the winding wheels 2 pass through the transition wheel 10, the steering wheel 8, and the pair of follower wheels 9 in this order. The conductive belt 3 on the middle winding wheel 2 extends a short distance in the horizontal direction, so that the conductive belt 3 on the middle winding wheel 2 directly turns through the steering wheel 8 and enters a pair of follower wheels 9. The structure of the transition wheel 10 is the same as that of the steering wheel 8.

The lifting shaft 1, the winding wheel 2, the transition wheel 10, the steering wheel 8 and the follower wheel 9 are all positioned above the base plate 7.

When the conductive belt 3 of this embodiment is installed, firstly, one end of the conductive belt 3 is inserted from the inlet of the first channel 25, and then enters the guide channel 24 closely along the inclined plane 252 or the cambered surface, and passes along the guide channel 24. At this time, the cable is still extended out of the conductive belt 3 (the belt body of the conductive belt 3 is peeled off in advance). The cable continues to enter the second channel 26 along the guide channel 24, the second channel 26 corresponds to the position of the wiring groove 1a, and the cable passes out of the wiring groove 1a on the lifting shaft 1 and is connected with the conductive slip ring 4. After the cable is connected, the pressing piece is placed from the notch 224 to fix the conductive belt 3 in the guide channel 24, and at this time, the fixing of the conductive belt 3 with the winding wheel 2 is completed. The other end of the conductive belt 3 is fixed with the grabbing mechanism through a transition wheel 10, a steering wheel 8 and a pair of follower wheels 9 in sequence. When the lifting shaft 1 rotates, since one end of the conductive belt 3 is fixed with the winding wheel 2, the conductive belt 3 is wound or unwound on the winding wheel 2 to lift the grabbing mechanism. In this process, on one hand, since the guide channel 24 between the outer ring surface 211 and the shaft hole 23 is machined on the winding wheel 2, the end of the conductive belt 3 is fixed in the guide channel 24, so that the conductive belt 3 can be tightly attached to the outer ring surface 211 of the winding wheel 2, and the positioning precision of the lifting movement of the conductive belt 3 is ensured. On the other hand, the guide channel 24, the channel II 26 and the wiring groove 1a are matched, so that the wiring of the cable is facilitated, and the cable is effectively protected.

The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and to implement the same, but are not intended to limit the scope of the present invention, and all equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of the present invention.

Claims

1. A lifting mechanism, characterized in that: comprising

The lifting shaft can rotate along the axis of the lifting shaft;

the winding wheels are provided with at least one winding wheel, are sleeved on the lifting shaft and synchronously rotate with the lifting shaft, each winding wheel comprises an outer ring surface, a shaft hole, a first channel, a second channel and a guide channel, the shaft hole is used for the lifting shaft to pass through, the guide channel is positioned between the shaft hole and the outer ring surface and surrounds the shaft hole, the guide channel is communicated with the first channel penetrating through the outer ring surface, and the second channel is arranged between the guide channel and the shaft hole and is communicated with the first channel;

the winding wheel comprises two end faces positioned on two sides of the outer ring face, each end face is provided with a channel along the axial direction, the channels are arranged on the corresponding end face at intervals along the circumferential direction, the channels on the two end faces are arranged in a staggered manner, and the channels on one end face can be communicated with two adjacent channels on the other end face;

The conductive slip ring is arranged at the end part of the lifting shaft, and the rotor end of the conductive slip ring is fixed with the lifting shaft and synchronously rotates.

2. The lifting mechanism of claim 1, wherein: the lifting belt is wound on the outer ring surface, and the inner end part of the lifting belt penetrating through the guide channel is fixed in the guide channel.

3. The lifting mechanism of claim 2, wherein: the first channel is arranged along the radial direction of the winding wheel, one side of the first channel, which is close to the outer ring surface, is provided with an inlet of the lifting belt, and a chamfer angle of an arc-shaped structure is formed between the side wall of the first channel at the inlet and the outer ring surface.

4. A lifting mechanism according to claim 3, wherein: the first passage is provided with at least one inclined plane or cambered surface, the lifting belt is attached to the inclined plane or cambered surface and enters the guide passage, and the cross section area of the first passage gradually increases from the position close to the outer annular surface to the position far away from the outer annular surface.

5. The lifting mechanism of claim 1, wherein: the guide channel surrounds the whole shaft hole; or the guide passage surrounds a portion of the shaft hole.

6. The lifting mechanism of claim 1, wherein: the winding wheel comprises a winding part and fixing parts located on two sides of the winding part along the axial direction, wherein the winding part and the fixing parts are of coaxial cylindrical structures, the diameter of the winding part is larger than that of the fixing parts, the side surfaces of the winding part are outer ring surfaces, the two surfaces of the fixing parts far away from the winding part are end surfaces provided with a channel, and the channel extends to the winding part.

7. The lifting mechanism of claim 6, wherein: the guide channel is internally provided with a notch communicated with the guide channel by pressing the end part of the lifting belt, the side wall of the fixing part is also provided with a bolt hole corresponding to the notch, and the pressing sheet is fixed with the fixing part by a bolt in threaded connection with the bolt hole.

8. The lifting mechanism of any one of claims 2-4, wherein: the winding wheels are respectively fixed with baffle plates positioned at two sides of the outer ring surface, the baffle plates are of annular structure and are coaxially arranged with the winding wheels, the baffle plates extend out of the winding wheel, and a cavity for winding the lifting belt is defined between the two baffle plates and the outer ring surface;

the baffle plate is provided with an inclined wedge surface towards one side of the outer annular surface, the wedge surfaces are arranged on the parts, extending out of the winding wheel, of the baffle plate, and each wedge surface flares outwards from one side close to the outer annular surface to one side far away from the outer annular surface.

9. The lifting mechanism of claim 8, wherein: the separation blade is split structure, including two at least components of a whole that can function independently portion every the separation blade that can splice to form an annular structure with the winding wheel detachable connection.

10. The lifting mechanism of claim 2, wherein: the lifting belt is a conductive belt, and a cable in the conductive belt enters the shaft hole from the second channel and passes through the winding wheel and the lifting shaft to be connected with the rotor end; the side wall of the lifting shaft is provided with a wiring groove along the axis, when the lifting shaft is in key joint with the winding wheel, the position of the wiring groove corresponds to a second channel, and a cable penetrating out of the second channel is connected to the rotor end of the conductive slip ring along the wiring groove.

11. The lifting mechanism of claim 1, wherein: the rotor end is connected with the lifting shaft through a connecting component, the connecting component comprises a connecting piece and a fixing piece, the connecting piece is fixed at the end part of the lifting shaft, and the fixing piece is used for connecting the rotor end with the connecting piece so as to realize synchronous rotation of the rotor end and the connecting piece.

12. The lifting mechanism of claim 11, wherein: the connecting piece comprises a round connecting plate and an annular vertical wall extending along the side surface of the connecting plate, the connecting plate is fixed with the end part of the lifting shaft, an inserting cavity for inserting a rotor end is defined between the connecting plate and the annular vertical wall, and the rotor end is inserted in the inserting cavity in a suspending manner; the part of the fixing piece, which is positioned in the inserting cavity, is tensioned to be a limiting plane which is jointed with the plane of the rotor end, the rotor end is positioned in a limiting cavity which is limited by the limiting plane and synchronously rotates with the limiting cavity under the pushing of the limiting plane, and the end part of the fixing piece passes through the limiting groove and is fixed on the outer wall of the annular vertical wall;

The fixing piece is a belt body made of metal or plastic, and the annular vertical wall is provided with a yielding groove for the end part of the belt body to pass through.

13. The lifting mechanism of claim 2, wherein: each lifting belt corresponds to one steering wheel, and the lifting belt horizontally extending from the winding wheel is turned to be vertical after passing through the steering wheel;

and a pair of follow-up wheels with adjustable intervals are arranged below each steering wheel, and the pair of follow-up wheels are respectively positioned at two sides of the lifting belt and are abutted against the side edges of the lifting belt.