CN113636419B

CN113636419B - Automatic knotting device for fiber bundle

Info

Publication number: CN113636419B
Application number: CN202110861751.2A
Authority: CN
Inventors: 田会方; 张国武; 吴迎峰; 任政
Original assignee: Wuhan University of Technology WUT
Current assignee: Wuhan University of Technology WUT
Priority date: 2021-07-29
Filing date: 2021-07-29
Publication date: 2023-02-07
Anticipated expiration: 2041-07-29
Also published as: CN113636419A

Abstract

The invention discloses an automatic fiber bundle knotting device which comprises a yarn pulling module, a yarn clamping module, a yarn winding module and a yarn shearing and knotting module, wherein the yarn pulling module is connected with the yarn clamping module; the yarn pulling module comprises an elastic clamp for clamping the butt joint end of the two fiber bundles and an inlet and outlet mechanism for driving the elastic clamp to enter and exit the working area of the yarn clamping module; the yarn clamping module comprises a front clamping mechanism and a rear clamping mechanism, the front clamping mechanism and the rear clamping mechanism are respectively used for clamping the upstream and downstream positions of the two folded fiber bundles, and the front clamping mechanism can adjust the clamping height; the yarn winding module is positioned between the front clamping mechanism and the rear clamping mechanism and comprises a knotting nozzle consisting of an upper jaw and a lower jaw, a rotating mechanism for driving the knotting nozzle to rotate, and an opening and closing mechanism for driving the upper jaw and the lower jaw to open and close; the yarn cutting and knot forming module comprises a cutter for cutting off a fiber bundle between the knotting nozzle and the front clamping mechanism, a yarn removing block for removing the fiber bundle from the knotting nozzle, a pulling block for tensioning knots on the fiber bundle and a transmission mechanism for driving the three to act. The device can automatically form knots, and has the advantages of short time, high knot forming rate and firm knot forming.

Description

Automatic fiber bundle knotting device

Technical Field

The invention belongs to the field of fiber winding equipment, and particularly relates to an automatic knotting device for a fiber bundle.

Background

The fiber bundle, especially the glass fiber bundle, generally has continuity requirement in the using process, and needs to tie and continue the fiber bundle head between the fiber groups on the creel. At present, most of glass fibers in winding processes are artificially knotted, filiform glass fibers floating in the air often appear in the knotting process, and after the glass fibers breathe into the lungs of a person, the glass cannot be absorbed and decomposed at all, so that deposition can be formed for a long time, occupational diseases similar to silicosis can be caused, and the health of the person is seriously influenced.

Disclosure of Invention

The invention aims to provide an automatic knot-tying device for fiber bundles, which can automatically form knots, and has the advantages of short knot-forming time, high knot-forming rate and firm knot formation.

The technical scheme adopted by the invention is as follows:

an automatic knotting device for fiber bundles comprises a yarn pulling module, a yarn clamping module, a yarn winding module and a yarn shearing and knotting module; the yarn pulling module comprises an elastic clamp for clamping the butt joint end of the two fiber bundles and an in-out mechanism for driving the elastic clamp to enter and exit a yarn clamping module working area; the yarn clamping module comprises a front clamping mechanism and a rear clamping mechanism, the front clamping mechanism and the rear clamping mechanism are respectively used for clamping the upstream and downstream positions of the two folded fiber bundles, and the front clamping mechanism can adjust the clamping height; the yarn winding module is positioned between the front clamping mechanism and the rear clamping mechanism and comprises a knotting nozzle consisting of an upper jaw and a lower jaw, a rotating mechanism for driving the knotting nozzle to rotate, and an opening and closing mechanism for driving the upper jaw and the lower jaw to open and close; the yarn cutting and knot forming module comprises a cutter for cutting off a fiber bundle between the knotting nozzle and the front clamping mechanism, a yarn removing block for removing the fiber bundle from the knotting nozzle, a pulling block for tensioning knots on the fiber bundle and a transmission mechanism for driving the three to act.

Furthermore, the in-out mechanism comprises a motor, a speed reducer, a coupler, a transmission shaft, a connecting rod and a yarn pulling rod which are sequentially connected, the motor, the speed reducer, the coupler and the transmission shaft are vertically installed, the end part of the transmission shaft is matched on a bearing seat through a bearing, the connecting rod and the yarn pulling rod are transversely installed, and the elastic clamp is located at the free end of the yarn pulling rod.

Furthermore, the front clamping mechanism comprises a fluted disc, a rotating assembly for driving the fluted disc to rotate, a floating clamping plate and a front counter-force assembly for applying adjustable counter-force to the back surface of the clamping plate, a tooth groove for hooking the fiber bundle is formed in the outer edge of the fluted disc, and the fluted disc rotates to a certain angle after hooking the fiber bundle and then compresses the fiber bundle in the tooth groove on the front surface of the clamping plate.

Further, preceding reaction subassembly includes leaf spring and adjusting screw, and the one end and the splint of leaf spring are connected, and the other end passes through adjusting screw and adjusts deformation.

Furthermore, the rear clamping mechanism comprises an active clamping block and a passive clamping block which are in sliding fit with the guide rail, a linear moving assembly for driving the active clamping block to move linearly, and a rear counter-force assembly for applying adjustable counter-force to the back of the passive clamping block, wherein a protrusion is arranged on the active clamping block, a groove which is matched with the protrusion is arranged on the front of the passive clamping block, and the protrusion compresses the fiber bundle in the groove after the active clamping block moves linearly to a certain position.

Furthermore, the back counter-force component comprises a middle block which is in sliding fit with the guide rail, a spring connected between the middle block and the passive clamping block, an adjusting screw rod for adjusting the position of the middle block, and a limiting piece for limiting the stroke of the middle block.

Further, rotary mechanism includes motor, reduction gear, shaft coupling and the transmission shaft of vertical connection in proper order, and the mouth of knoing is installed on the transmission shaft.

Furthermore, the opening and closing mechanism comprises a cam which does not rotate along with the knotting nozzle, a roller which is arranged on the upper jaw and attached to the cam, and a pressing component which is located at the ending position and can provide adjustable pressing force for the roller, the upper jaw is hinged to the lower jaw in a swinging mode, the roller is pushed away through a long-diameter area of the cam so as to keep the knotting nozzle open, and the roller is located at the ending position and presses a short-diameter area of the cam under the action of the pressing component so as to keep the knotting nozzle closed.

Furthermore, the compressing assembly comprises a pressing block, a pressure spring for applying pressing force to the pressing block and an adjusting piece for adjusting the working length of the pressure spring.

Furthermore, the transmission mechanism comprises a bottom frame and a linear motion assembly for driving the bottom frame to do linear motion, the cutter, the doffing block and the pulling block are arranged on the bottom frame, the cutter, the pulling block and the doffing block sequentially contact the fiber bundle during working, the cutter is close to the front clamping mechanism, the pulling block is close to the rear clamping mechanism, and the doffing block is positioned between the front clamping mechanism and the rear clamping mechanism.

The invention has the beneficial effects that:

the device sequentially decomposes the whole knotting process into five actions of yarn pulling, yarn clamping, yarn winding, yarn shearing and knotting, two fiber bundles are folded and pulled to a designated area by using a yarn pulling module, the fiber bundles are in a proper tight state by using a yarn clamping module to prepare for next yarn winding, the yarn winding module is used for simulating the rotating action of a thumb and a forefinger of a human hand, and the yarn winding forms a loose yarn

The device can automatically form knots, has short knot forming time, high knot forming rate and firm knot forming, and fibers after knot forming do not lose knots in the winding process.

Drawings

Fig. 1 is a perspective view of an automatic fiber bundle knotting apparatus according to an embodiment of the present invention.

Fig. 2 is a top view of a chassis in an embodiment of the invention.

FIG. 3 is a front view of a yarn pulling module according to an embodiment of the present invention.

Figure 4 is a top view of a clamping module (including a bottom tray) according to an embodiment of the invention.

Figure 5 is a front view of a yarn winding module according to an embodiment of the invention.

Figure 6 is a top view of a yarn cutting and tying module in accordance with an embodiment of the present invention.

FIG. 7 shows a first knotting operation, hooking yarn, in accordance with an embodiment of the present invention.

FIG. 8 shows a second knotting operation, pulling yarns, in accordance with an embodiment of the present invention.

FIG. 9 shows a third knotting operation, gripping, in accordance with an embodiment of the present invention.

FIG. 10 illustrates a fourth knotting operation in which the knotting tip is rotated 90 degrees, in accordance with an embodiment of the present invention.

FIG. 11 illustrates a fifth knotting operation in accordance with an embodiment of the present invention wherein the knotting tip is rotated 180 degrees.

FIG. 12 illustrates a sixth knotting operation in accordance with an embodiment of the present invention wherein the knotting tip is rotated 270 degrees.

FIG. 13 illustrates a seventh knotting operation in which the knotting tip is rotated 360 degrees, in accordance with an embodiment of the present invention.

FIG. 14 shows an eighth knotting action in accordance with an embodiment of the present invention, where the cut yarns are doffed to form knots.

FIG. 15 illustrates a ninth knotting operation and a reduction in accordance with an embodiment of the present invention.

In the figure:

100-chassis, 101-bearing seat, 102-connecting frame, 103-fixing seat and 104-guide rail;

200-yarn pulling module, 201-motor, 202-speed reducer, 203-coupler, 204-connecting frame, 205-transmission shaft, 206-bearing, 207-connecting rod, 208-yarn pulling rod and 209-elastic clamp;

300-yarn clamping module, 301-motor, 302-speed reducer, 303-coupler, 304-bearing seat, 305-fluted disc, 306-clamping plate, 307-leaf spring, 308-adjusting screw, 311-hexagonal rod cylinder, 312-connecting frame, 313-driving clamping block, 314-driven clamping block, 315-spring, 316-middle block, 317-adjusting screw rod and 318-limiting piece (nut);

400-yarn winding module, 401-motor, 402-reducer, 403-coupler, 404-transmission shaft, 405-supporting plate, 406-pressing block, 407-pressing spring, 408-adjusting piece (screwing nut), 409-lower jaw, 410-upper jaw, 411-roller, 412-cam;

500-cutting yarn and forming knot module, 501-cylinder, 502-connecting frame, 503-bottom frame, 504-doffing block, 505-pulling block, 506-cutter and 507-guide rail.

Detailed Description

The invention is further described below with reference to the figures and examples.

As shown in fig. 1 to 15, an automatic knotting device for fiber bundles comprises a yarn pulling module 200, a yarn clamping module 300, a yarn winding module 400 and a yarn cutting and knotting module 500; the yarn pulling module 200 comprises an elastic clamp 209 for clamping the butt joint end of two fiber bundles (the tail end of the fiber bundle of the yarn group in use and the head end of the fiber bundle of the prepared yarn group) and an in-out mechanism for driving the elastic clamp 209 to enter and exit the working area of the yarn clamping module 300; the yarn clamping module 300 comprises a front clamping mechanism and a rear clamping mechanism, the front clamping mechanism and the rear clamping mechanism are respectively used for clamping the upstream and downstream positions of two closed fiber bundles, and the clamping height of the front clamping mechanism can be adjusted; the yarn winding module 400 is positioned between the front clamping mechanism and the rear clamping mechanism and comprises a knotting nozzle consisting of an upper jaw (410) and a lower jaw (409), a rotating mechanism for driving the knotting nozzle to rotate, and an opening and closing mechanism for driving the upper jaw (410) and the lower jaw (409) to open and close, when in yarn winding, the knotting nozzle rotates to hook two fiber bundles and then opens, the front clamping mechanism reduces the clamping height again, and the knotting nozzle rotates again to the end position and is closed; the yarn cutting and knot forming module 500 comprises a cutter 506 for cutting off the fiber bundle between the knotting nozzle and the front clamping mechanism, a yarn removing block 504 for removing the fiber bundle from the knotting nozzle, a pulling block 505 for tensioning knots on the fiber bundle and a transmission mechanism for driving the three to act.

As shown in fig. 1 and fig. 2, for convenience of positioning and installation, the yarn pulling module 200, the yarn clamping module 300, the yarn winding module 400 and the yarn cutting and knotting module 500 are all installed on the chassis 100; the chassis 100 is provided with a bearing seat 101, a connecting frame 102, a fixed seat and a guide rail 104, the bearing seat 101 is used for supporting the yarn pulling module 200, the connecting frame 102 is used for installing a motor 301 required for yarn clamping, the fixed seat 103 is used for installing a fluted disc 305 and a clamping plate 306 in the yarn clamping module 300 and also installing a pressing block 406 in the yarn winding module 400, and the guide rail 104 is used for matching with a rear clamping mechanism of the yarn clamping module 300.

In the yarn pulling module 200:

as shown in fig. 3, the in-out mechanism includes a motor 201, a speed reducer 202, a coupler 203, a transmission shaft 205, a connection rod 207 and a yarn pulling rod 208, which are connected in sequence, the motor 201, the speed reducer 202, the coupler 203 and the transmission shaft 205 are vertically installed, the end of the transmission shaft 205 is matched on a bearing seat through a bearing 206, the connection rod 207 and the yarn pulling rod 208 are transversely installed, an elastic clamp 209 is located at a free end of the yarn pulling rod 208, and the motor 201 drives the yarn pulling rod 208 to swing left and right through forward and reverse rotation, so that the elastic clamp 209 is driven to enter and exit from a working area of the yarn clamping module 300. The yarn pulling module 200 is connected with the chassis 100 through a connecting frame 204, the transmission shaft 205 and the connecting rod 207, the connecting rod 207 and the yarn pulling rod 208, the yarn pulling rod 208 and the elastic clamp 209 are all fixedly connected through pins, the bearing 206 adopts a ball bearing, the speed reducer 202 adopts a planetary speed reducer, and the motor 201 adopts a stepping motor.

In the thread clamping module 300:

as shown in fig. 4, the front clamping mechanism includes a toothed disc 305, a rotating assembly for driving the toothed disc 305 to rotate, a floating clamp plate 306, and a front reaction assembly for applying an adjustable reaction force to the back of the clamp plate 306, wherein a toothed slot for hooking a fiber bundle is provided at the outer edge of the toothed disc 305, and the toothed disc 305 hooks the fiber bundle and rotates to a certain angle to press the fiber bundle in the toothed slot to the front of the clamp plate 306; the counter-force subassembly has guaranteed that the inseparable clamp of tow is difficult for deviating from under the frictional force effect between fluted disc and splint, and splint are unsteady, can guarantee the adjustable of centre gripping height, and the back-up force of counter-force subassembly is adjustable, can adjust required back-up force according to the centre gripping effect.

As shown in fig. 4, the rotating assembly includes a motor 301, a reducer 302, a coupler 303, and a connecting shaft, which is used for mounting a toothed disc 305 and is supported on a bearing block 304. As shown in FIG. 4, the front reaction force assembly comprises a plate spring 307 and an adjusting screw 308, wherein one end of the plate spring 307 is connected with the clamping plate 306, the other end of the plate spring is adjusted to deform through the adjusting screw 308, and the plate spring can be adjusted by operating the adjusting screw 308, so that the operation is convenient.

As shown in fig. 4, the rear clamping mechanism includes an active clamping block 313 and a passive clamping block 314 which are slidably fitted on the guide rail 104, a linear movement component for driving the active clamping block 313 to move linearly, and a rear reaction component for applying an adjustable reaction force to the back of the passive clamping block 314, wherein a protrusion is arranged on the active clamping block 313, a groove adapted to the protrusion is arranged on the front of the passive clamping block 314, the protrusion presses the fiber bundle in the groove after the active clamping block 313 moves linearly to a certain position, the reaction component ensures that the fiber bundle is tightly clamped in the groove and is not easy to fall off under the action of friction force, the reaction force of the reaction component is adjustable, and the required reaction force can be adjusted according to the clamping effect.

As shown in fig. 4, the linear moving unit employs a hexagonal rod cylinder 311, and the hexagonal rod cylinder 311 is mounted on the base plate 100 through a connection bracket 312. As shown in fig. 4, the back reaction force assembly includes an intermediate block 316 slidably fitted to the guide rail 104, a spring 315 connected between the intermediate block 316 and the passive clamp block 314, an adjustment screw 317 for adjusting the position of the intermediate block 316, and a stopper 318 for restricting the stroke of the intermediate block 315.

In the winding module 400:

as shown in fig. 5, the opening and closing mechanism comprises a cam 412 which does not rotate along with the knotting nozzle, a roller 411 which is arranged on an upper jaw 410 and is jointed with the cam 412, and a pressing component which is positioned at the ending position and can provide adjustable pressing force for the roller 411, the upper jaw 410 is hinged on a lower jaw 409 in a swinging mode, the roller 411 is pushed away through the long diameter area of the cam 412 so as to keep the knotting nozzle open, the roller 411 is pressed against the short diameter area of the cam 412 under the action of the pressing component when the roller is positioned at the ending position so as to keep the knotting nozzle closed, the opening and closing mechanism utilizes the power of a rotating mechanism to realize opening and closing, and the structure is simple and ingenious.

As shown in fig. 5, the rotating mechanism includes a motor 401, a reducer 402, a coupler 403 and a transmission shaft 404 which are vertically connected in sequence, and the knotting nozzle is installed on the transmission shaft 404. As shown in fig. 5, the pressing assembly includes a pressing block 406, a pressing spring 407 for applying a pressing force to the pressing block 406, and an adjusting member 408 for adjusting the working length of the pressing spring 407, the rotating mechanism and the cam 412 are mounted on a supporting plate 405, and the supporting plate 405 is mounted on the connecting frame 102 and the fixing base 103. The motor 401 is a stepping motor, the reducer 402 is a planetary reducer, and the roller 411 is a cylindrical roller.

In the cut yarn knotting module 500:

as shown in figure 6, the transmission mechanism comprises a bottom frame 503 and a linear motion assembly for driving the bottom frame to do linear motion, a cutter 506, a doffing block 504 and a pulling block 505 are arranged on the bottom frame 503, the cutter 506, the pulling block 505 and the doffing block 504 sequentially contact with a fiber bundle during working, the cutter 506 is close to the front clamping mechanism, the pulling block 505 is close to the rear clamping mechanism, and the doffing block 503 is positioned between the front clamping mechanism, the pulling block 505 and the rear clamping mechanism, so that the obtained yarn is drawn

The degree of knot tightening can be controlled by adjusting the amount of displacement of the pull block 505, i.e., the amount of extension of the linear motion assembly. As shown in fig. 6, the linear motion assembly includes a cylinder 501 and a guide 507, the cylinder 501 is mounted on the chassis 100 through a connecting frame 502, and the guide 507 is mounted on the chassis 100.

As shown in fig. 7 to 5, the knotting process is:

s1, two fiber bundles needing to be knotted and spliced are placed in an elastic clamp 209 in an aligning manner, a motor 201 drives a connecting rod 207 to rotate, the connecting rod 207 drives the elastic clamp 209 at the tail end of a yarn pulling rod 208 to rotate to be right above a fluted disc 305, the two fiber bundles enter a fluted disc of the fluted disc 305 at the moment, the motor 301 drives the fluted disc 305 to rotate anticlockwise to a position tightly attached and meshed with a clamping plate 306, the fluted disc 305 hooks the fiber bundles and rotates to a certain angle (about 30 degrees) to tightly press the fiber bundles in the fluted disc to the front side of the clamping plate 306, meanwhile, a hexagonal rod cylinder 311 pushes a driving clamping block 313 to advance, the driving clamping block 313 linearly moves to a certain position and then presses the fiber bundles in a groove of a driven clamping block 314 in a protruding manner, the motor 201 rotates in the opposite direction to drive the connecting rod 207 to reset, the yarn pulling rod 208 also resets, and the two fiber bundles are pulled out of the elastic clamp 209 under the action of a front clamping mechanism;

s2, the motor 401 drives the knotting nozzle (namely, the lower jaw 409 and the upper jaw 410) to rotate, a roller 411 on the upper jaw 410 is pushed away through a long-diameter area of the cam 412 to keep the knotting nozzle open, meanwhile, the motor 301 drives the fluted disc 305 to rotate anticlockwise for a certain angle (about 30 degrees), namely, the clamping height is reduced through the front clamping mechanism, so that two fiber bundles can enter between the lower jaw 409 and the upper jaw 410, the motor 401 drives the knotting nozzle to rotate to an end position (rotating for 360 degrees), when the roller 411 is located at the end position, the short-diameter area of the cam 412 is pressed under the action of the pressing assembly to keep the knotting nozzle closed, and the two fiber bundles are wound with yarns on the knotting nozzle and clamped between the lower jaw 409 and the upper jaw 410 for one circle;

s3, the air cylinder 501 pushes the bottom frame 503 to advance, in the advancing process, the cutter 506 cuts the fiber bundle between the knotting nozzle and the front clamping mechanism, the doffing block 504 takes off the fiber bundle wound in a circle from the knotting nozzle, and the pulling block 505 pulls the knots on the fiber bundle tightly to form a tight knot

Finally, the air cylinder 501 drives the bottom frame 503 to retreat and reset, and the hexagonal rod air cylinder 311 drives the active clamping block 313 to retreat and reset simultaneously, so that two parts are one in two

The knotted fiber bundle is removed.

The device decomposes the whole knotting process into five actions of yarn pulling, yarn clamping, yarn winding, yarn shearing and knotting in sequence, two fiber bundles are folded and pulled to a designated area by using a yarn pulling module 200, the fiber bundles are in a proper tight state by using a yarn clamping module 300 to prepare for next yarn winding, the yarn winding module 400 simulates the rotating actions of a thumb and a forefinger of a human hand, and the yarn winding forms a loose yarn

A shaped knot, a yarn cutting and knot forming module 500 is used for cutting yarn and tensioning to form the knot, and the deviceCan automatically form knots, has short knot forming time, high knot forming rate and firm knot formation, and the fibers after knot formation do not fall off in the winding process.

It will be understood that modifications and variations can be made by persons skilled in the art in light of the above teachings and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.

Claims

1. An automatic knotting device of tow which characterized in that: comprises a yarn pulling module, a yarn clamping module, a yarn winding module and a yarn cutting and binding module; the yarn pulling module comprises an elastic clamp for clamping the butt joint end of the two fiber bundles and an in-out mechanism for driving the elastic clamp to enter and exit a yarn clamping module working area; the yarn clamping module comprises a front clamping mechanism and a rear clamping mechanism, the front clamping mechanism and the rear clamping mechanism are respectively used for clamping the upstream and downstream positions of the two folded fiber bundles, and the front clamping mechanism can adjust the clamping height; the yarn winding module is positioned between the front clamping mechanism and the rear clamping mechanism and comprises a knotting nozzle consisting of an upper jaw and a lower jaw, a rotating mechanism for driving the knotting nozzle to rotate, and an opening and closing mechanism for driving the upper jaw and the lower jaw to open and close; the yarn cutting and knot forming module comprises a cutter for cutting off a fiber bundle between the knotting nozzle and the front clamping mechanism, a yarn removing block for removing the fiber bundle from the knotting nozzle, a pulling block for tensioning knots on the fiber bundle and a transmission mechanism for driving the three to act.

2. The automatic fiber bundle knotting device according to claim 1, wherein: the in-out mechanism comprises a motor, a speed reducer, a coupler, a transmission shaft, a connecting rod and a yarn pulling rod which are sequentially connected, the motor, the speed reducer, the coupler and the transmission shaft are vertically installed, the end part of the transmission shaft is matched on a bearing seat through a bearing, the connecting rod and the yarn pulling rod are transversely installed, and the elastic clamp is located at the free end of the yarn pulling rod.

3. The automatic fiber bundle knotting device according to claim 1, wherein: the front clamping mechanism comprises a fluted disc, a rotating assembly for driving the fluted disc to rotate, a floating clamping plate and a front counter-force assembly for applying adjustable counter-force to the back surface of the clamping plate, wherein a tooth groove for hooking a fiber bundle is formed in the outer edge of the fluted disc, and the fluted disc is used for hooking the fiber bundle and tightly pressing the fiber bundle in the tooth groove on the front surface of the clamping plate after rotating to a certain angle.

4. The automatic fiber bundle knotting device according to claim 3, wherein: the front counter-force assembly comprises a plate spring and an adjusting screw, one end of the plate spring is connected with the clamping plate, and the other end of the plate spring is adjusted to deform through the adjusting screw.

5. The automatic fiber bundle knotting device according to claim 1, wherein: the rear clamping mechanism comprises an active clamping block and a passive clamping block which are in sliding fit with the guide rail, a linear moving assembly for driving the active clamping block to move linearly, and a rear counter-force assembly for applying adjustable counter-force to the back of the passive clamping block, wherein a protrusion is arranged on the active clamping block, a groove matched with the protrusion is arranged on the front of the passive clamping block, and the protrusion compresses the fiber bundle in the groove after the active clamping block moves linearly to a certain position.

6. The automatic fiber bundle knotting device according to claim 5, wherein: the back reaction assembly comprises a middle block which is in sliding fit with the guide rail, a spring connected between the middle block and the passive clamping block, an adjusting screw for adjusting the position of the middle block, and a limiting part for limiting the stroke of the middle block.

7. The automatic fiber bundle knotting device according to claim 1, wherein: the rotating mechanism comprises a motor, a speed reducer, a coupler and a transmission shaft which are sequentially and vertically connected, and the knotting nozzle is arranged on the transmission shaft.

8. The automatic fiber bundle knotting device according to claim 1, wherein: the opening and closing mechanism comprises a cam which does not rotate along with the knotting nozzle, a roller which is arranged on the upper jaw and attached to the cam, and a pressing component which is located at the ending position and can provide adjustable pressing force for the roller, the upper jaw can be hinged on the lower jaw in a swinging mode, the roller is pushed away through a long-diameter area of the cam to keep the knotting nozzle open, and the roller is located at the ending position and presses a short-diameter area of the cam under the action of the pressing component to keep the knotting nozzle closed.

9. The automatic fiber bundle knotting apparatus of claim 8, wherein: the compressing assembly comprises a pressing block, a pressure spring for applying pressing force to the pressing block and an adjusting piece for adjusting the working length of the pressure spring.

10. The automatic fiber bundle knotting device according to claim 1, wherein: the transmission mechanism comprises a bottom frame and a linear motion assembly for driving the bottom frame to do linear motion, the cutter, the doffing block and the pulling block are arranged on the bottom frame, the cutter, the pulling block and the doffing block sequentially contact the fiber bundle during working, the cutter is close to the front clamping mechanism, the pulling block is close to the rear clamping mechanism, and the doffing block is positioned between the front clamping mechanism and the rear clamping mechanism.