CN115027143A

CN115027143A - Cylinder side surface UV lithography apparatus

Info

Publication number: CN115027143A
Application number: CN202210733961.8A
Authority: CN
Inventors: 王功庆; 涂高俊; 许贵林
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-06-24
Filing date: 2022-06-24
Publication date: 2022-09-09

Abstract

The invention discloses a cylinder side surface UV printing device, which comprises: the base, the inner chamber of base is provided with conveying mechanism, and the rear side fixed mounting of base has the stand, the front side top of stand is provided with the printing component, the right side of stand is provided with drive feed mechanism, the controller is installed to the front side of base, just conveying mechanism, printing component and drive feed mechanism all with controller electric connection. This cylinder side surface UV lithography apparatus can make the feeding motor pass through coupling assembling and remove subassembly high-speed joint, can carry out the material loading for subsequent removal subassembly at the printing in-process, avoids frequent clamping material loading, reduces the latency of course of working, is suitable for continuous large batch printing to can drive the rotatory appointed radian of stock through the rotation angle of control feeding motor output, with the stock that is suitable for different diameters.

Description

Cylinder side surface UV lithography apparatus

Technical Field

The invention relates to the technical field of printers, in particular to UV printing equipment for the side surface of a cylinder.

Background

The UV printing is a printing process for drying and curing ink through ultraviolet rays, the ink containing a photosensitizer needs to be matched with a UV curing lamp, the application of the UV printing is one of the most important contents in the printing industry, the UV printing covers the fields of offset printing, silk screen, ink jet, pad printing and the like, the UV which is generally indicated in the traditional printing world is a print effect process, namely, a layer of gloss oil (with gloss, matte, inlaid crystals, glitter powder and the like) is wrapped on a pattern which is printed with a wanted pattern, the brightness and artistic effect of the product are mainly increased, the surface of the product is protected, the hardness is high, the corrosion and friction resistance is realized, the scratch is not easy to occur, and the UV is changed into the UV at present for some multi-film products, so that the environmental protection requirement can be met;

in the prior art, when printing is carried out on the side surface of a cylindrical printing stock such as a vacuum cup, a pop can and the like, a special clamp is usually arranged below a printing probe of a UV printer, the special clamp fixes the printing stock, a rotating shaft controls the rotation of the printing stock, and the transverse and rotary combined motion of the printing stock during printing realizes 360-degree uninterrupted printing on the outer side surface of the cylindrical printing stock, so that the purpose of one-step forming of the printing on the outer side surface of the cylindrical printing stock is achieved;

common lithography apparatus that can carry out the stamp to the cylinder side surface in the market, need carry out the material loading through certain charging apparatus or manual work, carry out the unloading again after the printing finishes, the printing waits for the clearance long, can't carry out continuous printing, only can carry out the customization of small batch, be difficult to accomplish extensive stamp, furthermore, the diameter size diverse of stock, the interval of the outer peripheral face that leads to ink gun and cylinder is inconsistent, there is big or small, and under the different condition of stock diameter, the corresponding feed volume of the same angle of rotation is also different, thereby influence the problem of printing quality, be difficult to be suitable for the stock of different diameters, can't satisfy the demand of big batch printing.

Disclosure of Invention

The invention aims to provide a cylindrical side surface UV printing device, which at least solves the problems that the prior art cannot continuously print in large batch and cannot be suitable for printing stocks with different diameters.

In order to achieve the purpose, the invention provides the following technical scheme: a cylinder side surface UV printing apparatus, comprising: the base, the inner chamber of base is provided with conveying mechanism, and the rear side fixed mounting of base has the stand, the front side top of stand is provided with the printing component, the right side of stand is provided with drive feed mechanism, the controller is installed to the front side of base, just conveying mechanism, printing component and drive feed mechanism all with controller electric connection.

Preferably, the printing assembly comprises: install the first slip table on stand front side top, the removal end fixed mounting of first slip table has the lift seat, the right side of lift seat is provided with the second slip table, the removal end fixed mounting of second slip table has the movable block, the ink jet set is installed on the bottom right side of movable block, glow discharge lamp is installed in the bottom left side of movable block, first slip table, second slip table, ink jet set and glow discharge lamp all with controller electric connection.

Preferably, the conveying mechanism includes: fixed mounting is in the conveyor motor of base rear side right-hand member, just conveyor motor and controller electric connection, the transmission shaft is all rotatably installed at both ends about the inner chamber rear side of base, is located the right side the transmission shaft is with conveyor motor's output fixed connection, two the equal fixed mounting of outer wall of transmission shaft has the sprocket, two the tooth lateral wall of sprocket has cup jointed the chain, the equal fixed mounting in both sides has annular spout, two around the inner chamber of base both ends all seted up flutedly, two about annular spout a plurality of removal subassembly, a plurality of are installed to the inner chamber slidable of annular spout remove subassembly and chain fixed connection, the top front side intermediate position fixed mounting of base has locating component, just locating component and controller electric connection.

Preferably, the moving assembly includes: fixed mounting is in the dead lever in the chain outside, the dead lever top is provided with removes the seat, it all rotatably installs first pulley, two to remove the front and back both sides left end of seat first pulley slidable install in the inner chamber of two annular spouts respectively, just the dead lever is corresponding with the position of two first pulleys, remove the seat around both sides right-hand member all rotatably install the second pulley, two install in the inner chamber of two annular spouts second pulley slidable respectively, remove the inner chamber rear side of seat about both ends rotatably install two drive rollers respectively, remove the front side of seat about both ends rotatably install two synchronizing wheels respectively, and two the synchronizing wheel respectively with two drive roller fixed connection, two the hold-in range has been cup jointed to the outer wall of synchronizing wheel.

Preferably, the positioning assembly comprises: install the proximity switch of the top front side of base, proximity switch and controller electric connection, the top front side fixed mounting who removes the seat has the stopper.

Preferably, the drive feed mechanism includes: fixed mounting is at the feed motor on stand right side, feed motor and controller electric connection, the output fixed mounting of feeding motor has the drive wheel, the front side of drive wheel is opened and is equipped with the synchronization groove, every the rear side of removing the subassembly all is provided with coupling assembling.

Preferably, the connection assembly includes: set up remove the installation cavity of seat rear side right-hand member, the draw-in groove has all been seted up to the upper and lower both sides of installation cavity, the installation cavity inner chamber rotatably installs the swiveling wheel, swiveling wheel and the drive roller fixed connection that is located the right side, the rear side fixed mounting of swiveling wheel has synchronous piece, first spout has been seted up at the top of swiveling wheel, the second spout has been seted up on the top of synchronous piece, the connection chamber has been seted up between first spout and the second spout, the extrusion piece is installed to the inner chamber slidable of second spout, the fixture block is installed to the inner chamber slidable of first spout, be provided with the connecting block between extrusion piece and the fixture block, just install at the connection chamber lateral wall connecting block slidable, be provided with the spring between the inner chamber bottom of connecting block and connection chamber.

Compared with the prior art, the UV printing equipment for the side surface of the cylinder has the beneficial effects that:

1. the controller drives the output end of the conveying motor to drive the transmission shaft and the chain wheel connected with the conveying motor to rotate, so that the moving assembly is driven by the chain to move towards the left side, when the proximity switch detects the limit block, the synchronous groove extrudes the extrusion block, the extrusion block drives the connecting block to slide downwards, the clamp block releases the limit on the clamp groove, the feeding motor can drive the rotating wheel to rotate through the driving wheel, and after printing is finished, the controller controls the feeding motor to enable the synchronous groove and the synchronous block to rotate and to be fixedly stopped in the horizontal direction so as to be connected with the driving wheel next time.

2. The controller controls the output end of the feeding motor to drive the driving wheel to rotate, the driving wheel drives the driving roller connected with the driving wheel to rotate through the connecting component, and the two driving rollers synchronously rotate in the same direction under the driving action of the synchronous belt and the two synchronous wheels to drive the printing stock to rotate.

Drawings

FIG. 1 is a schematic view of the structure of the present invention;

FIG. 2 is a front sectional view of the present invention;

FIG. 3 is a left side view of the present invention;

FIG. 4 is a right side sectional view of the present invention;

FIG. 5 is an enlarged view at A;

FIG. 6 is a top view of the present invention;

FIG. 7 is a schematic view of a moving assembly;

FIG. 8 is a rear view of the moving assembly;

fig. 9 is a right sectional view of the moving assembly.

In the figure: 2. a base, 3, a column, 4, a printing assembly, 41, a first sliding table, 42, a lifting seat, 43, a second sliding table, 44, a moving block, 45, an ink jet, 46, a glow discharge lamp, 5, a conveying mechanism, 51, a conveying motor, 52, a transmission shaft, 53, a chain wheel, 54, a chain, 55, a circular sliding groove, 56, a groove, 57, a moving assembly, 571, a moving seat, 572, a fixing rod, 573, a first pulley, 574, a second pulley, 575, a driving roller, 576, a synchronizing wheel, 577, a synchronous belt, 58, a positioning assembly, 581, a proximity switch, 582, a limiting block, 6, a driving feeding mechanism, 61, a feeding motor, 62, a driving wheel, 63, a synchronous groove, 64, a connecting assembly, 641, a mounting cavity, 642, a clamping groove, 643, a rotating wheel, 644, a synchronous block, 645, a first sliding groove, a second sliding groove, 647, a connecting cavity, 648, an extrusion block, 649, a glow discharge lamp, a connecting assembly, a mounting cavity, a glow discharge lamp, a, Connecting block 6410, fixture block 6411, spring 7 and controller.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-9, in an embodiment of the present invention, an apparatus for UV printing on a side surface of a cylinder includes: base 2, stand 3, printing component 4, conveying mechanism 5, drive feed mechanism 6 and controller 7, the inner chamber of base 2 is provided with conveying mechanism 5, the rear side fixed mounting of base 2 has stand 3, the front side top of stand 3 is provided with printing component 4, the right side of stand 3 is provided with drive feed mechanism 6, controller 7 is installed to the front side of base 2, and conveying mechanism 5, printing component 4 and drive feed mechanism 6 all with controller 7 electric connection.

As shown in fig. 1-2, further, the printing element 4 preferably comprises: a first sliding table 41, a lifting seat 42, a second sliding table 43, a moving block 44, an ink jet 45 and a glow discharge lamp 46, the first sliding table 41 is installed on the top end of the front side of the upright post 3, the lifting seat 42 is fixedly installed on the moving end of the first sliding table 41, the second sliding table 43 is installed on the right side of the lifting seat 42, the moving block 44 is fixedly installed on the moving end of the second sliding table 43, the ink jet 45 is installed on the right side of the bottom of the moving block 44, the glow discharge lamp 46 is installed on the left side of the bottom of the moving block 44, the inner wall of the vacuum fluorescent tube is uniformly coated with a thin coating containing mercury components, ion discharge is generated by providing voltage difference (voltage drop) to the electrodes at the two ends, so as to generate ultraviolet radiation, the ultraviolet radiation generally emitted by the glow discharge lamp is low in ultraviolet temperature and is commonly called cold ultraviolet, the first sliding table 41, the second sliding table 42, the ink jet 45 and the glow discharge lamp 46 are all electrically connected with the controller 7, the controller 7 is modularly assembled by internal CPU, instruction and data memory, input/output unit, power module, digital analog unit, etc., and stores instructions for executing operations such as logic operation, sequence control, timing, counting, arithmetic operation, etc. in its interior, and controls various types of mechanical equipment or production processes through digital or analog input/output.

As shown in fig. 1 to 4, the conveying mechanism 5 preferably includes: a conveying motor 51, a transmission shaft 52, chain wheels 53, chains 54, annular chutes 55, grooves 56, a moving assembly 57 and a positioning assembly 58, the conveying motor 51 is fixedly installed at the right end of the rear side of the base 2, the conveying motor 51 is electrically connected with the controller 7, the transmission shaft 52 is rotatably installed at the left and right ends of the rear side of the inner cavity of the base 2, the transmission shaft 52 at the right side is fixedly connected with the output end of the conveying motor 51, the chain wheels 53 are fixedly installed on the outer walls of the two transmission shafts 52, the tooth side walls of the two chain wheels 53 are sleeved with the chains 54, the chain wheels 53 and the chains 54 form chain transmission, the chain transmission is a transmission mode of transmitting the motion and power of the chain wheels 53 with special tooth shapes to the chain wheels 53 with special tooth shapes through the chains 54, the annular chutes 55 are fixedly installed at the front and rear sides of the inner cavity of the base 2, the grooves 56 are formed at the left and right ends of the two annular chutes 55, a plurality of moving assemblies 57 are slidably mounted in the inner cavities of the two annular sliding grooves 55, the plurality of moving assemblies 57 are fixedly connected with the chain 54, a positioning assembly 58 is fixedly mounted in the middle of the front side of the top of the base 2, and the positioning assembly 58 is electrically connected with the controller 7.

As shown in fig. 7-9, further, the moving assembly 571 comprises: a movable seat 571, a fixed rod 572, a first pulley 573, a second pulley 574, driving rollers 575, synchronizing wheels 576 and a synchronizing belt 577, the fixed rod 572 is fixedly installed outside the chain 54, the movable seat 571 is arranged on the top of the fixed rod 572, the first pulleys 573 are rotatably installed at the left ends of the front and back sides of the movable seat 571, the two first pulleys 573 are slidably installed in the inner cavities of the two annular chutes 55 respectively, the fixed rod 572 corresponds to the positions of the two first pulleys 573, the second pulleys 574 are rotatably installed at the right ends of the front and back sides of the movable seat 571, the two second pulleys 574 are slidably installed in the inner cavities of the two annular chutes 55 respectively, the two driving rollers 575 are rotatably installed at the left and right ends of the rear side of the inner cavity of the movable seat 571 respectively, the two synchronizing wheels 576 are rotatably installed at the left and right ends of the front side of the movable seat 571 respectively, and the two synchronizing wheels 576 are fixedly connected with the two driving rollers 575 respectively, synchronous belts 577 are sleeved on the outer walls of the two synchronous wheels 576, synchronous belt transmission is formed by the synchronous wheels 576 and the synchronous belts 577, annular belts with tooth shapes at equal intervals are arranged on the inner circumferential surface of the synchronous belts 577, the synchronous wheels 576 are wheels with corresponding fit of conveying belts, the synchronous belt transmission integrates the advantages of belt transmission, chain transmission and gear transmission, and power is transmitted by meshing the teeth of the synchronous belts 577 and the tooth grooves of the synchronous wheels 576 during rotation.

Preferably, as shown in fig. 4 or 6, further, the positioning assembly 58 includes: the proximity switch 581 is a position switch which can be operated without mechanical direct contact with a moving part, when the sensing surface of the object proximity switch reaches an action distance, the proximity switch 581 can be operated without mechanical contact and any pressure is applied to drive a direct current appliance or provide a control instruction for the controller 7, and the front side of the top of the movable seat 571 is fixedly provided with the limit block 582.

As shown in fig. 4 to 5, preferably, the driving feed mechanism 6 further includes: feed motor 61, drive wheel 62, synchronization groove 63 and coupling assembling 64, fixed mounting is at the feed motor 61 on stand 3 right side, feed motor 61 and controller 7 electric connection, the output fixed mounting of feed motor 61 has drive wheel 62, the front side of drive wheel 62 is opened and is equipped with synchronization groove 63, every rear side that removes subassembly 57 all is provided with coupling assembling 64, when removing the place ahead that subassembly 57 reachd drive wheel 62, drive wheel 62 is connected with drive roller 575 through coupling assembling 64.

As shown in fig. 8-9, further, the connecting assembly 64 preferably includes: the installation cavity 641, the clamping groove 642, the rotating wheel 643, the synchronizing block 644, the first sliding groove 645, the second sliding groove 646, the connecting cavity 647, the extrusion block 648, the connecting block 649, the fixture block 6410 and the spring 6411, the installation cavity 641 is arranged at the right end of the rear side of the movable seat 572, the clamping groove 642 is respectively arranged at the upper side and the lower side of the installation cavity 641, the rotating wheel 643 is rotatably installed in the inner cavity of the installation cavity 641, the rotating wheel 643 is fixedly connected with the driving roller 575 positioned at the right side, the synchronizing block 644 is fixedly installed at the rear side of the rotating wheel 643, the first sliding groove 645 is arranged at the top of the rotating wheel 643, the second sliding groove 646 is arranged at the top end of the synchronizing block 644, the connecting cavity 647 is arranged between the first sliding groove 645 and the second sliding groove 646, the extrusion block 648 is slidably installed in the inner cavity of the second sliding groove 646, the fixture block 6410 is slidably installed in the inner cavity of the first sliding groove 645, the connecting block 649 is slidably arranged between the extrusion block 648 and the connecting block 649, and the connecting block 649 is installed on the side wall of the connecting cavity 647, be provided with spring 6411 between the inner chamber bottom of connecting block 648 and connecting chamber 647, spring 6411 is rotational spring, produce elastic deformation after receiving the extrusion, resume to initial condition after removing external force, make connecting block 648 and the top in close contact with who connects chamber 647 under spring 6411's spring action, thereby make fixture block 6410 and draw-in groove 642 carry out the joint, synchronous block 644 is the level this moment, receive the extrusion lapse down when extrusion block 648, connecting block 648 overcomes spring 6411 elasticity lapse, thereby make fixture block 6410 relieve spacing to draw-in groove 642.

The detailed connection means is well known in the art, and the following mainly describes the working principle and process, and the specific operation is as follows.

Firstly, the printing stock is placed at the top ends of two driving rollers 575 of a moving assembly 57, a controller 7 drives the output end of a conveying motor 51 to drive a transmission shaft 52 and a chain wheel 53 connected with the output end to rotate, so that the moving assembly 57 is driven to move towards the left side by a chain 54, and when a limit block 582 is detected by a proximity switch 581, the moving assembly 57 is in place, and the controller 7 controls the conveying motor 51 to brake;

step two, when the proximity switch 581 detects the limit block 582, the sync block 644 is just inserted into the sync slot 63, the inner wall of the sync slot 63 extrudes the extrusion block 648, the extrusion block 648 drives the connection block 648 to slide downwards against the elastic force of the spring 6411, so that the fixture block 6410 relieves the limit of the slot 642, at this time, the feeding motor 61 can drive the rotation wheel 643 to rotate through the driving wheel 62, under the driving action of the sync belt 577 and the two sync wheels 576, the two driving rollers 575 rotate synchronously in the same direction, the printed material can be driven to rotate, and the controller 7 can drive the positions of the inkjet device 45 and the glow discharge lamp 46 and print the printed material by controlling the first sliding table 41 and the second sliding table 43;

step three, after printing is finished, the controller 7 controls the feeding motor 61 to enable the synchronous groove 63 and the synchronous block 644 to rotate and stay in the horizontal direction, the controller 7 controls the conveying motor 51 to rotate, the moving assembly 57 is conveyed leftwards, the synchronous block 644 slides and separates along the synchronous groove 63, the synchronous groove 63 releases the limit of the extrusion block 648, the connecting block 648 is pushed to slide upwards under the action of the elastic force of the spring 6411, the connecting block 648 is enabled to be in tight contact with the top of the connecting cavity 647, the clamping block 6410 is in clamping connection with the clamping groove 642, and the synchronous block 644 is fixed in the horizontal direction so as to be connected with the driving wheel 62 at the next time;

the invention can drive the printing stock to rotate by a designated radian, can be suitable for printing stocks with different diameters, can ensure that the feeding motor is quickly connected with the moving assembly through the connecting assembly, avoids frequent clamping, reduces the intermittent time of the processing process and is suitable for continuous large-batch printing.

The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. In the description of the present invention, it is to be understood that the indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings and are merely for convenience in describing the present invention and for simplifying the description, but are not intended to indicate or imply that the indicated devices or elements must have the specified orientations, be constructed in the specified orientations, and be operated, and all equivalent changes or modifications made according to the spirit of the present invention are intended to be covered within the scope of the present invention.

Claims

1. A cylinder side surface UV printing apparatus, comprising: base (2), the inner chamber of base (2) is provided with conveying mechanism (5), and the rear side fixed mounting of base (2) has stand (3), the front side top of stand (3) is provided with printing component (4), the right side of stand (3) is provided with drive feed mechanism (6), controller (7) are installed to the front side of base (2), just conveying mechanism (5), printing component (4) and drive feed mechanism (6) all with controller (7) electric connection.

2. The cylinder side surface UV printing apparatus according to claim 1, wherein: the printing assembly (4) comprises: install first slip table (41) on stand (3) front side top, the removal end fixed mounting of first slip table (41) has lift seat (42), the right side of lift seat (42) is provided with second slip table (43), the removal end fixed mounting of second slip table (43) has movable block (44), ink jet set (45) are installed on the bottom right side of movable block (44), glow discharge lamp (46) are installed in the bottom left side of movable block (44), first slip table (41), second slip table (42), ink jet set (45) and glow discharge lamp (46) all with controller (7) electric connection.

3. The cylinder side surface UV printing apparatus according to claim 1, wherein: the conveying mechanism (5) comprises: the conveying motor (51) is fixedly installed at the right end of the rear side of the base (2), the conveying motor (51) is electrically connected with the controller (7), transmission shafts (52) are rotatably installed at the left end and the right end of the rear side of the inner cavity of the base (2), the transmission shafts (52) positioned on the right side are fixedly connected with the output end of the conveying motor (51), chain wheels (53) are fixedly installed on the outer walls of the two transmission shafts (52), chains (54) are sleeved on the tooth side walls of the two chain wheels (53), annular sliding grooves (55) are fixedly installed on the front side and the rear side of the inner cavity of the base (2), grooves (56) are formed in the left end and the right end of the two annular sliding grooves (55), a plurality of moving assemblies (57) are slidably installed in the inner cavities of the two annular sliding grooves (55), and the plurality of moving assemblies (57) are fixedly connected with the chains (54), the top front side middle position fixed mounting of base (2) has locating component (58), just locating component (58) and controller (7) electric connection.

4. The cylinder side surface UV printing apparatus according to claim 3, wherein: the moving assembly (571) comprises: a fixed rod (572) fixedly installed on the outer side of the chain (54), a movable seat (571) is arranged at the top of the fixed rod (572), first pulleys (573) are rotatably installed at the left ends of the front side and the rear side of the movable seat (571), the two first pulleys (573) are respectively slidably installed in the inner cavities of the two annular sliding grooves (55), the fixed rod (572) corresponds to the two first pulleys (573), second pulleys (574) are rotatably installed at the right ends of the front side and the rear side of the movable seat (571), the two second pulleys (574) are respectively slidably installed in the inner cavities of the two annular sliding grooves (55), two driving rollers (575) are respectively rotatably installed at the left end and the right end of the rear side of the inner cavity of the movable seat (571), and two synchronizing wheels (576) are respectively rotatably installed at the left end and the right end of the front side of the movable seat (571), and two synchronizing wheel (576) respectively with two drive rollers (575) fixed connection, two the outer wall of synchronizing wheel (576) has cup jointed hold-in range (577).

5. The cylinder side surface UV printing apparatus according to claim 4, wherein: the positioning assembly (58) comprises: the proximity switch (581) is installed on the front side of the top of the base (2), the proximity switch (581) is electrically connected with the controller (7), and a limiting block (582) is fixedly installed on the front side of the top of the moving seat (571).

6. The cylinder side surface UV printing apparatus according to claim 4, wherein: the drive feed mechanism (6) includes: fixed mounting is at feeding motor (61) on stand (3) right side, feeding motor (61) and controller (7) electric connection, the output fixed mounting of feeding motor (61) has drive wheel (62), the front side of drive wheel (62) is opened and is equipped with synchronization groove (63), every the rear side of removal subassembly (57) all is provided with coupling assembling (64).

7. The cylinder side surface UV printing apparatus according to claim 6, wherein: the connection assembly (64) includes: the installation cavity (641) is arranged at the right end of the rear side of the movable seat (572), clamping grooves (642) are formed in the upper side and the lower side of the installation cavity (641), a rotating wheel (643) is rotatably installed in the inner cavity of the installation cavity (641), the rotating wheel (643) is fixedly connected with a driving roller (575) located on the right side, a synchronizing block (644) is fixedly installed on the rear side of the rotating wheel (643), a first sliding groove (645) is formed in the top of the rotating wheel (643), a second sliding groove (646) is formed in the top end of the synchronizing block (644), a connecting cavity (647) is formed between the first sliding groove (645) and the second sliding groove (646), an extrusion block (648) is slidably installed in the inner cavity of the second sliding groove (646), a clamping block (6410) is slidably installed in the inner cavity of the first sliding groove (645), and a connecting block (649) is arranged between the extrusion block (648) and the clamping block (6410), and the connecting block (649) can be slidably arranged on the side wall of the connecting cavity (647), and a spring (6411) is arranged between the connecting block (648) and the bottom of the inner cavity of the connecting cavity (647).