CN219381887U - Attaching jig of display device - Google Patents

Abstract

The utility model provides a fitting jig of a display device, which comprises a fitting box, wherein a fitting adsorption plate can adsorb a fitting cover plate in vacuum, and a piston shaft of an adjusting cylinder is fixedly provided with an adjusting rod; the bottom of the inner cavity of the laminating box is fixedly provided with a laminating base, the laminating base is fixedly provided with a heat-conducting plate, a storage cavity is formed between the elastic bag and the surface of the laminating base, a containing cavity is formed between the piston plate and the bottom of the concave regulating block groove, and a display module can be placed on the elastic bag; the heat transfer plate is arranged at the position of the bonding base close to the heat transfer plate, and the fan device is used for stirring the hot air heated by the movable heating device. The utility model provides a fitting jig of a display device, which can be used for fitting a curved screen with a bending area, and can promote the mutual fitting between a flexible board of a display module and a fitting cover plate during fitting, so that the fitting is firmer and the using effect is better.

Description

Attaching jig of display device

Technical Field

The utility model relates to the technical field of laminating devices, in particular to a laminating jig of a display device.

Background

In the prior art, a jig, a laminating device and a method for laminating a display screen and a touch screen, which are disclosed as CN107599589A, comprise a workbench, wherein a protection box is fixedly connected to the left side surface of the workbench, a controller is fixedly arranged in the protection box, a supporting metal pipe is fixedly connected to the middle end of the top of the workbench, a supporting plate is fixedly connected to the top of the supporting metal pipe, and supporting columns are fixedly connected to the top of the workbench and positioned on two sides of the supporting plate; the jig, the laminating device and the method for laminating the display screen and the touch screen are simple in structure and convenient to use, air can be heated through the heating wire, external air flow is accelerated through the rotation of the motor, hot air can be taken away when the hot air passes through the heating wire and enters the heating groove to heat the heating plate, the situation that the heating plate is at the heat degree can prevent glue on a glass plate from solidifying quickly, the problem that the glue is solidified quickly when encountering cold is solved, and the quality is reduced after the touch screen is supported is solved.

However, during the use process, the method still has obvious defects: the supporting plate and the extruding plate in the device are both planar, so that the device can only be suitable for the lamination of the planar display module, however, along with the popularization of the curved surface screen, most of the existing display devices are provided with bending areas, and the supporting plate and the extruding plate cannot be well laminated, so that improvement is needed.

Disclosure of Invention

The present utility model is directed to a bonding fixture for a display device, so as to solve the problems set forth in the background art.

In order to achieve the above purpose, the present utility model provides the following technical solutions:

the utility model provides a display device's laminating tool, includes the laminating case, the inner chamber top of laminating case is provided with the crossbeam lead screw that can be driven rotatory, the screw thread is provided with first nut piece on the crossbeam lead screw, the fixed lift cylinder that is provided with in bottom of first nut piece, the epaxial laminating adsorption plate that is provided with of piston of lift cylinder, laminating adsorption plate can vacuum adsorption laminating apron, the second through groove has been seted up to laminating adsorption plate's both ends symmetry, just all be provided with the governing cylinder in the second through groove, the epaxial fixed regulation pole that is provided with of piston of governing cylinder;

the device comprises a laminating box, wherein a laminating base is fixedly arranged at the bottom of an inner cavity of the laminating box, a heat conducting plate is fixedly arranged on the laminating base, a plurality of supporting protruding blocks are fixedly arranged on the heat conducting plate, elastic bags are covered on the outer sides of the heat conducting plate and the plurality of supporting protruding blocks, a storage cavity is formed between the elastic bags and the surface of the laminating base, concave adjusting blocks are fixedly arranged on two sides of the top surface of the laminating base, piston plates are movably arranged in grooves of the concave adjusting blocks, a containing cavity is formed between the piston plates and the bottoms of the grooves of the concave adjusting blocks, the containing cavity is communicated with the storage cavity through a communicating pipe, the top of the piston plates is connected with a limiting block through a spring, the limiting block is fixed on the inner wall of the grooves of the concave adjusting blocks, and a display module can be placed on the elastic bags;

the heat transfer plate is arranged at the position of the bonding base close to the heat transfer plate, a movable heating device and a fan device are arranged in an inner cavity of the bonding base, and the fan device is used for stirring hot air heated by the movable heating device.

Preferably, one end of the beam screw rod is fixed on an output shaft of the driving motor, the other end of the beam screw rod is arranged in the first bearing seat, and the driving motor and the first bearing seat are both fixed on the inner wall of the bonding box.

Preferably, the attaching adsorption plate is provided with an adsorption hole, a first through groove and an air hole which are sequentially communicated, and the air hole is communicated with the vacuum pump.

Preferably, the heat-conducting plate and the plurality of supporting protruding blocks are integrally formed.

Preferably, the movable heating device comprises an adjusting screw rod which is hinged, the adjusting screw rod can be driven by the power device to rotate, a second nut block is arranged on the adjusting screw rod in a threaded mode, and a heating plate is arranged on one side, facing the heat transfer plate, of the second nut block.

Preferably, a heat insulation plate is fixedly arranged between the second nut block and the heating plate.

Preferably, the fan device comprises a transmission rod which is hinged, the transmission rod can be driven by the power device to rotate, and a plurality of fan blades are fixedly arranged on the transmission rod.

Preferably, the power device comprises a rotating motor, one end of a transmission rod is fixed at the output end of the rotating motor, the other end of the transmission rod is arranged in a second bearing seat, a driving wheel is fixedly sleeved on the transmission rod, the driving wheel is connected with a driven wheel through transmission of a transmission belt, the driven wheel is fixedly sleeved on an adjusting screw, two ends of the adjusting screw are respectively arranged in a third bearing seat and a fourth bearing seat, and the rotating motor, the second bearing seat, the third bearing seat and the fourth bearing seat are all fixedly arranged on the side wall of an inner cavity of the attaching base.

Compared with the prior art, the utility model has the beneficial effects that:

1. according to the utility model, the laminating base is fixedly arranged at the bottom of the inner cavity of the laminating box, the heat-conducting plate is fixedly arranged on the laminating base, the plurality of supporting protruding blocks are fixedly arranged on the heat-conducting plate, and the elastic bags are covered on the outer sides of the heat-conducting plate and the plurality of supporting protruding blocks, so that the device can laminate a curved screen display device with a bending area;

2. the elastic bag can expand and contract, the pressure of an internal medium can be adjusted, so that an impetus is formed for the display module, the flexible plate of the display module and the attaching cover plate are more tightly attached, and the problems of unsound attaching, bubbles at attaching positions and the like are avoided;

3. according to the utility model, the movable heating device and the fan device are arranged in the inner cavity of the bonding base, and the fan device is used for stirring the hot air heated by the movable heating device, so that the top surface of the bonding base can be kept at a certain temperature, the glue between the bonding cover plate and the display module can not be rapidly cooled, the bonding is convenient to adjust, and local unstable or air bubbles are avoided.

The utility model provides a fitting jig of a display device, which can be used for fitting a curved screen with a bending area, and can promote the mutual fitting between a flexible board of a display module and a fitting cover plate during fitting, so that the fitting is firmer and the using effect is better.

Drawings

FIG. 1 is a schematic cross-sectional front view of the overall structure of the present utility model;

FIG. 2 is a schematic cross-sectional front view of the internal structure of the conformable base of the present utility model;

fig. 3 is an enlarged view of fig. 2 at a in accordance with the present utility model.

In the figure: the device comprises a bonding box 1, a beam screw rod 2, a driving motor 3, a first bearing seat 4, a first nut block 5, a lifting cylinder 6, a bonding adsorption plate 7, a 701 adsorption hole, a first through groove 702, a 703 air hole, a second through groove 704, a vacuum pump 8, a regulating cylinder 9, a regulating rod 10, a bonding cover plate 11, a bonding base 12, a heat-conducting plate 13, a supporting convex block 131, a flexible bag 14, a storage cavity 141, a concave regulating block 15, a holding cavity 151, a piston plate 16, a communicating pipe 17, a spring 18, a limiting block 19, a display module 20, a heat transfer plate 21, a regulating screw rod 22, a driving rod 23, a rotating motor 24, a second bearing block 25, a driving wheel 26, a driving belt 27, a driven wheel 28, a third bearing seat 29, a fourth bearing seat 30, a second nut block 31, a heat-insulating plate 32, a heating plate 33 and a fan blade 34.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Referring to fig. 1 to 3, the present utility model provides a technical solution:

embodiment one:

the utility model provides a display device's laminating tool, including laminating case 1, the inner chamber top of laminating case 1 is provided with can be driven rotatory crossbeam lead screw 2, the screw thread is provided with first nut piece 5 on the crossbeam lead screw 2, when crossbeam lead screw 2 is driven rotatory, first nut piece 5 can be along crossbeam lead screw 2 removal, the fixed lift cylinder 6 that is provided with in bottom of first nut piece 5, the fixed laminating adsorption plate 7 that is provided with on the piston shaft of lift cylinder 6, lift cylinder 6 under the start-up state can drive laminating adsorption plate 7 and carry out the adjustment of high position, laminating adsorption plate 7 can vacuum adsorption laminating apron 11, vacuum adsorption is not only firm, can also avoid polluting or damaging laminating apron 11, second through groove 704 has been seted up to laminating adsorption plate 7's both ends symmetry, and all be provided with in the second through groove 704 and adjust cylinder 9, the epaxial fixed regulation pole 10 that is provided with of piston of adjust cylinder 9, adjust cylinder 9 can drive the removal of adjusting pole 10.

The inner chamber bottom of laminating case 1 is fixed and is provided with laminating base 12, laminating base 12 is last to be fixed to be provided with heat-conducting plate 13, heat-conducting plate 13 can even heat conduction, the fixed outside cover that is provided with a plurality of support boss 131 on heat-conducting plate 13, heat-conducting plate 13 and a plurality of support boss 131 is equipped with elastic bag 14, elastic bag 14 has good elasticity of stretching out and drawing back, form the reservoir 141 between elastic bag 14 and the laminating base 12 surface, the top surface both sides of laminating base 12 are all fixed and are provided with concave regulating block 15, all move about in the recess of concave regulating block 15 and be provided with piston plate 16, piston plate 16 can be laminated the recess inner wall of concave regulating block 15 and remove, form between piston plate 16 and the concave regulating block 15 recess bottom and hold chamber 151, hold chamber 151 and communicate in reservoir 141 through communicating pipe 17, all store the fluidic medium that heat conductivility is good in reservoir 141, communicating pipe 17 and hold chamber 151, such as pure water or heat conduction oil etc., both can flow in a flexible way according to the shape of display module 20, make the edge portion such as piston zone is more laminated in the top of a flexible display module 16, the top of buckling more has the stopper 18 to be connected in the recess of concave regulating block 15, flexible bag 14 can be placed in the elastic bag 14, flexible display module 19 is more flexible, can be placed in the elastic bag 14 inside flexible bag 20, the flexible display module is more flexible, and is placed in the inside the recess of the flexible bag is more flexible, the flexible bag 20.

The position of the laminating base 12, which is close to the heat conducting plate 13, is provided with a heat transfer plate 21, the heat transfer plate 21 is embedded to be arranged in the top panel of the laminating base 12, a movable heating device and a fan device are arranged in the inner cavity of the laminating base 12, and the fan device is used for stirring the hot air heated by the movable heating device, so that the heat transfer plate 21 can be heated.

Embodiment two:

the utility model provides a laminating tool of display device, including laminating case 1, laminating case 1's inner chamber top is provided with crossbeam lead screw 2 that can be driven rotatory, the one end of crossbeam lead screw 2 is fixed in on the output shaft of driving motor 3, the other end sets up in first bearing frame 4, and driving motor 3 and first bearing frame 4 are all fixed in on laminating case 1's the inner wall, the screw thread is provided with first nut piece 5 on crossbeam lead screw 2, when crossbeam lead screw 2 is driven rotatory, first nut piece 5 can remove along crossbeam lead screw 2, driving motor 3 is bi-directional rotating machine, after driving motor 3 starts, can drive crossbeam lead screw 2 and take place corotation or reversal, and then drive first nut piece 5 moves towards different directions, the bottom of first nut piece 5 is fixed and is provided with lift cylinder 6, the epaxial fixed laminating adsorption plate 7 that is provided with of piston of lift cylinder 6, lifting cylinder 6 under the start-up state can drive laminating adsorption plate 7 and carry out the adjustment of altitude, laminating adsorption plate 7 can vacuum adsorption laminating apron 11, vacuum adsorption is not only firm, can also avoid polluting or damaging laminating apron 11, in this embodiment, set up in laminating adsorption plate 7 and communicate in proper order adsorption port 701, first logical groove 702 and gas pocket 703, gas pocket 703 communicates in vacuum pump 8, vacuum pump 8 loops through gas pocket 703, first logical groove 702 back acts on adsorption port 701 for adsorption port 701 produces vacuum adsorption force, and then will laminate apron 11 and adsorb firmly, second logical groove 704 has been seted up to laminating adsorption plate 7's both ends symmetry, and all be provided with adjusting cylinder 9 in the second logical groove 704, the epaxial fixed regulation pole 10 that is provided with of piston of adjusting cylinder 9, adjusting cylinder 9 can drive the removal of adjusting pole 10.

The bottom of the inner cavity of the laminating box 1 is fixedly provided with a laminating base 12, the laminating base 12 is fixedly provided with a heat conducting plate 13, the heat conducting plate 13 can conduct heat uniformly, the heat conducting plate 13 is fixedly provided with a plurality of supporting protruding blocks 131, the heat conducting plate 13 and the supporting protruding blocks 131 are integrally formed, the whole is more stable, the heat conducting effect is better, the outer side of the heat conducting plate 13 and the plurality of supporting protruding blocks 131 is covered with an elastic bag 14, the elastic bag 14 has good telescopic elasticity, a storage cavity 141 is formed between the elastic bag 14 and the surface of the laminating base 12, both sides of the top surface of the laminating base 12 are fixedly provided with concave adjusting blocks 15, piston plates 16 are movably arranged in grooves of the concave adjusting blocks 15, the piston plates 16 can move along the inner walls of grooves of the concave adjusting blocks 15, the piston plate 16 and concave adjusting block 15 form between the recess bottom and hold the chamber 151, hold the chamber 151 and communicate in storing the chamber 141 through communicating pipe 17, store the chamber 141, communicating pipe 17 and hold and all store the fluidic medium that heat conductivility is good in the chamber 151, such as pure water or conduction oil etc. can both conduct heat, can flow in a flexible way according to the shape of display module assembly 20 again, make edge portion such as bending zone laminate more, the top of piston plate 16 is connected in stopper 19 through spring 18, spring 18 has good elasticity that stretches out and draws back, stopper 19 is fixed in on the recess inner wall of concave adjusting block 15, can place display module assembly 20 on the elastic bag 14, and the inside conduction fluidic medium of elastic bag 14 can free flow, make elastic bag 14 laminate display module assembly 20 more.

The position of the bonding base 12 close to the heat conducting plate 13 is provided with a heat transfer plate 21, in this embodiment, the heat transfer plate 21 may be a copper plate, the heat transfer plate 21 is embedded to be arranged in the top panel of the bonding base 12, the inner cavity of the bonding base 12 is provided with a movable heating device and a fan device, and the fan device is used for stirring the hot air heated by the movable heating device, so that the heat transfer plate 21 can be heated.

Embodiment III:

the present embodiment further discloses and defines a specific structure of the movable heating device based on the first embodiment or the second embodiment, and specifically: the movable heating device comprises an adjusting screw 22 which is hinged, the adjusting screw 22 can be driven by a power device to rotate, a second nut block 31 is arranged on the adjusting screw 22 in a threaded mode, when the adjusting screw 22 is driven to rotate forwards or reversely, the second nut block 31 can move forwards or reversely along the adjusting screw 22, a heating plate 33 is arranged on one side, facing the heat transfer plate 21, of the second nut block 31, the heating plate 33 can generate heat, the display module 20 is further heated through the heat transfer plate 21, the heat transfer plate 13 and a heat transfer medium and the like, quick cooling and hardening of adhesive between the display module 20 and the attaching cover plate 11 are avoided, the display module 20 and the attaching cover plate 11 can be fixed after aligning and attaching, attaching effect is improved, a heat insulation plate 32 is fixedly arranged between the second nut block 31 and the heating plate 33, and the heat insulation plate 32 can be prevented from being thermally damaged after the heating plate 33 is continuously heated.

Embodiment four:

the present embodiment further discloses and defines a specific structure of the fan device based on the first embodiment or the second embodiment, and specifically: the fan device includes the drive rod 23 that articulates the setting, the drive rod 23 can be driven by power device and then take place to rotate, and fixed a plurality of flabellums 34 of being provided with on the drive rod 23, after the drive rod 23 is driven rotatory, a plurality of flabellums 34 can take place to rotate thereupon, and then produce the air current, promote the inside gas flow of laminating base 12, make the different positions of heat transfer plate 21 all can heat up because of the heat conduction, but, the local temperature of heat transfer plate 21 that the heating plate 33 corresponds can be higher, and then can realize local heating to display module assembly 20, be fit for the control to key region, avoid glue rapid cooling and dry hard, and then can realize laminating apron 11 and the alignment laminating of display module assembly 20 more steadily.

Fifth embodiment:

the present embodiment further discloses and defines a specific structure of the power device on the basis of the third embodiment and the fourth embodiment, and specifically: the power device comprises a rotating motor 24, the rotating motor 24 is a bidirectional rotating motor, forward rotation and reverse rotation can occur, one end of a transmission rod 23 is fixed at the output end of the rotating motor 24, the other end of the transmission rod 23 is arranged in a second bearing seat 25, therefore, the rotating motor 24 can drive the transmission rod 23 to rotate, a driving wheel 26 is fixedly sleeved on the transmission rod 23, the driving wheel 26 is connected with a driven wheel 28 through a transmission belt 27, the driven wheel 28 is fixedly sleeved on an adjusting screw 22, therefore, the driving wheel 26 on the transmission rod 23 drives the driven wheel 28 on the adjusting screw 22 to rotate through the transmission belt 27, two ends of the adjusting screw 22 are respectively arranged in a third bearing seat 29 and a fourth bearing seat 30, the adjusting screw 22 can stably rotate in situ, and the rotating motor 24, the second bearing seat 25, the third bearing seat 29 and the fourth bearing seat 30 are fixedly arranged on the side wall of an inner cavity of the attaching base 12.

Working principle:

in use, the display module 20 is first placed on the outside of the elastic bag 14, and then the attaching cover plate 11 is vacuum-adsorbed on the bottom of the attaching adsorption plate 7. When laminating, can drive crossbeam lead screw 2 rotation for first nut piece 5 takes place to remove, and then indirectly drives laminating apron 11 and take place the displacement, until laminating apron 11 aim at display module assembly 20 after, start lift cylinder 6, lift cylinder 6 can drive laminating apron 11 through laminating adsorption plate 7 and descend, makes laminating apron 11 laminating at display module assembly 20's upper surface.

Meanwhile, the adjusting cylinders 9 on two sides can be independently or simultaneously started, the adjusting cylinders 9 can drive the adjusting rods 10 to extend downwards, the adjusting rods 10 press the piston plate 16 downwards, so that the heat conducting medium in the accommodating cavity 151 is extruded to the storage cavity 141 along the communicating pipe 17, the elastic bag 14 is further expanded, the elastic bag 14 is attached to the bottom surface of the display module 20 and generates thrust to the display module 20, and the display module 20 and the attaching cover plate 11 are attached to each other, particularly, the edge of a bending area is attached to each other, and the problems of air bubbles and the like are avoided.

If the heat-conducting plate is used under the condition of low ambient temperature, in order to avoid the bonding glue from being cooled and dried and hard too fast, the heating plate 33 can be started, so that the heating plate 33 continuously generates heat, the adjusting screw 22 can lead the second nut block 31 to move when rotating, and the heating plate 33 can heat the heat transfer plates 21 in different areas in a key way; when the transmission rod 23 is driven to rotate, the fan blades 34 rotate, so that air flow is generated, air flow inside the attaching base 12 is promoted, and different positions of the heat transfer plates 21 can be heated due to heat conduction, but the local temperature of the heat transfer plates 21 corresponding to the heating plates 33 is higher, so that the display module 20 can be locally heated, the control of key areas is realized, the glue is prevented from being rapidly cooled and dried and hard, and the alignment attaching of the attaching cover plate 11 and the display module 20 can be realized more stably.

Although embodiments of the present utility model have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents.

Claims (8)

1. The utility model provides a display device's laminating tool, includes laminating case (1), its characterized in that: the device is characterized in that a beam screw rod (2) capable of being driven to rotate is arranged at the top of an inner cavity of the laminating box (1), a first nut block (5) is arranged on the beam screw rod (2) in a threaded mode, a lifting cylinder (6) is fixedly arranged at the bottom of the first nut block (5), a laminating adsorption plate (7) is fixedly arranged on a piston shaft of the lifting cylinder (6), a laminating cover plate (11) can be adsorbed by the laminating adsorption plate (7), second through grooves (704) are symmetrically formed in two ends of the laminating adsorption plate (7), adjusting cylinders (9) are arranged in the second through grooves (704), and adjusting rods (10) are fixedly arranged on the piston shaft of the adjusting cylinders (9);

the utility model discloses a thermal insulation box, including laminating base (12) and piston plate (16), including laminating base (12), heat conduction plate (13) are gone up fixedly and are provided with a plurality of supports protruding piece (131), the outside cover of heat conduction plate (13) and a plurality of supports protruding piece (131) is equipped with elastic bag (14), form between elastic bag (14) and laminating base (12) surface and store chamber (141), the top surface both sides of laminating base (12) are all fixed and are provided with concave regulating block (15), all be provided with piston plate (16) in the recess of concave regulating block (15) activity, form between piston plate (16) and concave regulating block (15) recess bottom and hold chamber (151), hold chamber (151) through communicating pipe (17) intercommunication in store chamber (141), the top of piston plate (16) is connected in stopper (19) through spring (18), stopper (19) are fixed in on the recess inner wall of concave regulating block (15), can place on elastic display module (20);

the heat transfer plate (21) is arranged at the position of the bonding base (12) close to the heat transfer plate (13), a movable heating device and a fan device are arranged in the inner cavity of the bonding base (12), and the fan device is used for stirring hot air heated by the movable heating device.

2. The bonding jig of a display device according to claim 1, wherein: one end of the beam screw rod (2) is fixed on an output shaft of the driving motor (3), the other end of the beam screw rod is arranged in the first bearing seat (4), and the driving motor (3) and the first bearing seat (4) are both fixed on the inner wall of the bonding box (1).

3. The bonding jig of a display device according to claim 1, wherein: an adsorption hole (701), a first through groove (702) and an air hole (703) which are sequentially communicated are formed in the attaching adsorption plate (7), and the air hole (703) is communicated with the vacuum pump (8).

4. The bonding jig of a display device according to claim 1, wherein: the heat conducting plate (13) and the plurality of supporting protruding blocks (131) are integrally formed.

5. The bonding jig of a display device according to claim 1, wherein: the movable heating device comprises an adjusting screw rod (22) which is hinged, the adjusting screw rod (22) can be driven by a power device to rotate, a second nut block (31) is arranged on the adjusting screw rod (22) in a threaded mode, and a heating plate (33) is arranged on one side, facing the heat transfer plate (21), of the second nut block (31).

6. The bonding jig of a display device according to claim 5, wherein: a heat insulation plate (32) is fixedly arranged between the second nut block (31) and the heating plate (33).

7. The bonding jig of a display device according to claim 6, wherein: the fan device comprises a transmission rod (23) which is hinged, the transmission rod (23) can be driven by the power device to rotate, and a plurality of fan blades (34) are fixedly arranged on the transmission rod (23).

8. The bonding jig of a display device according to claim 7, wherein: the power device comprises a rotating motor (24), one end of a transmission rod (23) is fixed at the output end of the rotating motor (24), the other end of the transmission rod is arranged in a second bearing seat (25), a driving wheel (26) is fixedly sleeved on the transmission rod (23), a driven wheel (28) is connected with the driving wheel (26) through a transmission belt (27), the driven wheel (28) is fixedly sleeved on an adjusting screw (22), two ends of the adjusting screw (22) are respectively arranged in a third bearing seat (29) and a fourth bearing seat (30), and the rotating motor (24), the second bearing seat (25), the third bearing seat (29) and the fourth bearing seat (30) are fixedly arranged on the side wall of an inner cavity of a jointing base (12).