阅读说明：本技术 一种一步成型的自加捻纳米纤维纱线的连续制备装置及方法 (Continuous preparation device and method of self-twisting nanofiber yarn formed in one step ) 是由 石磊 王云 胡艳丽 庄旭品 程博闻 张毅 林小琳 于 2021-09-14 设计创作，主要内容包括：本发明提供了一种一步成型的自加捻纳米纤维纱线的连续制备装置,涉及纳米纤维纱线的纺织加工技术领域。该装置包括纺丝单元、收集单元和卷绕单元,纺丝单元主要由溶液供给装置、共轭喷丝模头、静电发生器和压缩气泵组成。纺丝液从共轭喷丝模头射出,在电场和气流场的双重作用下射流被牵伸、细化、固化成高度取向的纳米纤维,经旋转漏斗加捻成纱后收集在卷取辊上。本发明方法降低了溶液成纤的静电电压和气压,原料适用性广,操作简单,成纱效率高,尤其是制备的纯纳米纤维纱线品质好,不仅取向度高,结构均匀,孔隙率大而且力学性能优异,有望实现纳米纤维在诸多领域的应用。(The invention provides a continuous preparation device of self-twisting nanofiber yarns formed in one step, and relates to the technical field of spinning and processing of nanofiber yarns. The device comprises a spinning unit, a collecting unit and a winding unit, wherein the spinning unit mainly comprises a solution supply device, a conjugate spinning die head, an electrostatic generator and a compressed air pump. The spinning solution is ejected from a conjugate spinning die head, jet flow is drafted, refined and solidified into highly oriented nano fibers under the dual actions of an electric field and an air flow field, and the highly oriented nano fibers are twisted into yarns by a rotary funnel and then collected on a winding roller. The method reduces the electrostatic voltage and air pressure of solution fiber forming, has wide raw material applicability, simple operation and high yarn forming efficiency, particularly has good quality of the prepared pure nanofiber yarn, high orientation degree, uniform structure, large porosity and excellent mechanical property, and is expected to realize the application of the nanofiber in various fields.)

1. A one-step forming continuous preparation device of self-twisting nanofiber yarns is characterized in that: comprises a spinning unit, a collecting unit and a winding unit; the spinning unit mainly comprises a solution supply device, a conjugate spinning die head, an electrostatic generator and a compressed air pump, wherein the spinning die head is formed by nesting an inner needle of the die head and an outer needle of the die head, and the two needles are not in contact with each other to form an annular gap for air flow to pass through; the solution supply device is connected with the inner needle of the die head to provide spinning solution, and the compressed air pump is connected with the outer needle of the die head to provide auxiliary air flow; the two metal spinning die heads are respectively connected with the positive electrode and the negative electrode of the electrostatic generator through cables.

2. The collecting unit of claim 1 comprises a horizontally mounted motor, a through hole is arranged on the center line of the motor, and the front end of the motor is connected with the funnel collector and can drive the funnel to rotate. The vertical height of the funnel collector is lower than that of the spinning die head.

3. The winding unit according to claim 1 comprises a winding roller, a yarn guide hook and a fixing plate, wherein the winding roller is connected with a motor through a coupler; the yarn guide hook is connected with the coupler through a gear and reciprocates at one side of the fixed plate along with the winding of the winding roller; a circular through hole is formed above the fixing plate and is positioned on the same horizontal axis with the through holes of the funnel collector and the motor; the collecting unit and the winding unit are fixed on the insulating plate together.

4. The solution supply device according to claim 1, comprising a feed plate, a feed screw, and a syringe; the injector fixed to the feed plate is pressed by the rotation of the screw shaft to supply the spinning solution. The injector is communicated with the die head inner needle through a transfusion tube.

5. The spinning die head of claim 1, wherein the vertical height of the spinning die head is higher than that of the funnel collector, the distance between the spinning die head and the funnel collector is adjustable, and the adjustment range is 10-20 cm; the spinning die heads are fixed on the support and are positioned at the same height, the distance between the two die heads ranges from 5 cm to 20cm, and the angle ranges from 0 degree to 90 degrees; and the two spinning die heads are respectively wound with metal wires and extend out for a certain length to be used as auxiliary electrodes.

6. The hopper collector of claim 2 having a take-off roll mounted to the rear thereof.

7. The compressed air source of claim 1 being an air compressor.

8. The spinning unit of claim 1 including a fan mounted on the housing.

9. The use method of the one-step forming-based self-twisting nanofiber yarn continuous preparation device is characterized by comprising the following steps of:

step 1: fixing the injector added with the spinning solution on a silk feeding plate, and connecting the injector with an inner needle of a die head by using a liquid conveying pipe;

step 2: nesting and assembling the die head inner needle and the die head outer needle into a spinning die head which is arranged on a bracket, adjusting the distance of the spinning die head and setting the angle between the die heads;

and step 3: connecting the two spinning die heads with the anode and the cathode of an electrostatic generator respectively through wires, winding the two die heads respectively through metal wires, and reserving a certain length as an auxiliary electrode to dissipate charges;

and 4, step 4: the yarn wound on the yarn withdrawing roller sequentially passes through the motor, the funnel, the fixing plate and the yarn guide hook and is fixed on the winding roller;

and 5: turning on a motor of the solution supply device and setting the moving speed of the filament plate;

step 6: turning on a high-voltage power supply to set spinning voltage, turning on an air compressor to set air pressure, and turning on a fan;

and 7: opening a controller to set the rotating speed of a funnel collector and the winding speed of a winding roller so as to ensure that a yarn guide hook reciprocates in a certain area;

and 8: the spinning solution jet flow is sprayed out from the surface of a spinning die head, and is stretched, thinned and solidified into filaments under the dual actions of an electrostatic field and an air flow field; the fan is helpful for the volatilization of the solvent and the humidity maintenance of the box body; after a stable triangular inverted cone is formed on the surface of the funnel collector, cutting the yarn from a yarn withdrawal roller, controlling the size of the electrostatic voltage and the angle and the size of circular blowing air sprayed by a spinning die head to ensure that the fiber deposition amount on the funnel collector is stable, ensuring that the nanofiber filamentation process and the yarn formation process of the yarn are carried out simultaneously, and if the nanofiber core-spun yarn is spun, the yarn does not need to be cut;

and step 9: and (4) after the nanofiber yarn prepared in the step (8) passes through the yarn guide hook, winding can be carried out along with the rotation of the winding roller, and the continuous collection of the yarn can be realized by replacing a yarn drum.

Technical Field

The invention belongs to the technical field of textile processing, and particularly relates to a one-step forming self-twisting nanofiber yarn continuous preparation device and a preparation method by utilizing an electrostatic blowing technology.

Background

The nano-fiber is a kind of superfine fiber with the fiber diameter in the nano-scale range prepared by a special mode. Compared with common fibers obtained by a traditional textile process, the nanofiber has strong surface activity, is easy to perform functional finishing, has small-size effect, quantum-size effect and quantum tunnel effect, and shows special properties which are not possessed by common fibers in various fields of mechanics, thermodynamics, optics, electrics, magnetics and the like. These characteristics make nanofibers the first choice material for many important applications, and have already gained certain practical applications in the fields of biomedical, tissue engineering, high efficiency filtration, intelligent wear, environmental protection, etc.

However, most of the nanofiber products are nanofiber felts, the internal structures of the nanofibers are disordered, the secondary processing performance of the nanofiber felts is poor, and the problem of processing the nanofiber felts into other products is solved, so that the nanofiber yarns with stable mechanical properties and weavability are produced. The nanofiber yarn is a nanofiber aggregate prepared by applying a certain twist to an oriented nanofiber bundle with a certain length-diameter ratio. The nanofiber yarn with twist realizes the conversion of fiber dimension from nanometer to micrometer, and simultaneously has the unique advantages of excellent anisotropy and nanostructure of the yarn. The nanofiber yarn can participate in subsequent treatment and secondary processing processes such as modification, weaving and the like in a three-dimensional nanostructure, the added value of products is increased, the application of the nanofiber in various fields is realized, and the application market of textiles is further widened.

The existing spinning processing methods of nanofiber yarns mainly comprise electrostatic spinning, centrifugal spinning, solution jet spinning and the like. Chinese patent CN 109355715 a discloses a conjugated electrostatic spinning device which can orderly coat nanofibers on a core yarn at a certain angle to form a nanofiber core-spun yarn.

The preparation method of the PVA nanofiber yarn disclosed in the Chinese patent CN IO 7268129A introduces a method for preparing a pure nanofiber yarn. The PVA nanofiber membrane spun by the electrostatic spinning technology is cut, twisted and drawn to obtain the PVA nano yarn with controllable twist. The yarn can be independently formed without depending on core yarn, the added value of products is further increased, but the yarn is limited in length and low in production efficiency, and industrial production cannot be realized. Chinese patent CN IO 5887223A adopts a high-speed centrifugal spinning device to collect and twist nanofibers by means of rotation of a centrifugal column, thereby realizing preparation of nanofiber yarns by one-step forming, but the fiber diameter distribution of spun yarns is wide, and the yarn twist is not obvious.

Chinese patent CN 110644080 a discloses a continuous preparation device and method for preparing nanofiber yarn by using solution jet method, the method gathers, straightens and gathers fibers into bundles by venturi effect, finally twists into yarn by twisting device. The solution jet method is safe and simple to operate, can effectively improve the yield of the nanofiber yarns, is expected to realize large-scale continuous production of the nanofiber yarns, but the prepared fibers are thick in diameter, and the fluctuation of an air field around a spinning die head is severe, so that the forming process of the yarns is unstable, and the obtained yarns are poor in appearance.

The invention designs a one-step forming continuous preparation device of self-twisting nanofiber yarns by combining the advantages of electrostatic spinning and solution jet spinning. The electrostatic voltage and air pressure lower than solution fiber forming are selected in the yarn forming process, jet flow is drafted, refined, solidified and twisted under the double actions of an electric field and an air flow field to form the highly oriented nanofiber yarn.

Disclosure of Invention

The invention aims to provide a device and a method for continuously preparing self-twisted electrostatic melt-blown nanofiber yarns, and aims to solve the problems of poor stability, uncontrollable yarn twist, poor yarn strength and the like in a yarn forming process. The invention can be used for preparing the nanofiber core-spun yarn and pure nanofiber yarn.

In order to solve the above problems, the technical solution provided by the present invention is as follows:

the continuous preparation device of the self-twisting nanofiber yarn formed in one step comprises a spinning unit, a collecting unit and a winding unit. The spinning unit mainly comprises a solution supply device, a conjugate spinning die head, an electrostatic generator and a compressed air pump, wherein the spinning die head is formed by nesting an inner needle of the die head and an outer needle of the die head, and the two needles are not in contact with each other to form an annular gap for air flow to pass through. The solution supply device is connected with the inner needle of the die head to provide spinning solution, and the compressed air pump is connected with the outer needle of the die head to provide auxiliary air flow. The two metal spinning die heads are respectively connected with the positive electrode and the negative electrode of the electrostatic generator through cables.

The collecting unit comprises a motor which is horizontally arranged, a through hole is formed in the center line of the motor, and the front end of the motor is connected with the funnel collector and can drive the funnel to rotate. The vertical height of the funnel collector is lower than that of the spinning die head.

The winding unit comprises a winding roller, a yarn guide hook and a fixing plate, and the winding roller is connected with a motor through a coupler; the yarn guide hook is connected with the coupler through a gear and reciprocates along with the winding of the winding roller on one side of the fixed plate. A circular through hole is formed above the fixing plate and is positioned on the same horizontal axis with the through holes of the funnel collector and the motor. The collecting unit and the winding unit are fixed on the insulating plate together.

Optionally, the solution supply device comprises a wire feeding plate, a lead screw and an injector. The injector fixed to the feed plate is pressed by the rotation of the screw shaft to supply the spinning solution. The injector is communicated with the die head inner needle through a transfusion tube.

Optionally, the vertical height of the spinning die head is higher than that of the funnel collector, the distance between the spinning die head and the funnel collector is adjustable, and the adjusting range is 10-20 cm.

Optionally, the spinneret die heads are fixed on the support and located at the same height, the distance between the two die heads ranges from 5 cm to 20cm, and the angle ranges from 0 to 90 degrees.

Optionally, the two spinning die heads are respectively wound with metal wires and extend out for a certain length to serve as auxiliary electrodes.

Optionally, a yarn withdrawal roller is mounted behind the funnel collector.

Optionally, the compression air pump is an air compressor.

Optionally, the spinning unit comprises a fan mounted on the housing.

The invention provides a use method of the one-step forming self-twisting nanofiber yarn continuous preparation device, which is characterized by comprising the following steps of:

step 1: fixing the injector added with the spinning solution on a silk feeding plate, and connecting the injector with an inner needle of a die head by using a liquid conveying pipe;

step 2: nesting and assembling the die head inner needle and the die head outer needle into a spinning die head which is arranged on a bracket, adjusting the distance of the spinning die head and setting the angle between the die heads;

and step 3: connecting the two spinning die heads with the anode and the cathode of an electrostatic generator respectively through wires, winding the two die heads respectively through metal wires, and reserving a certain length as an auxiliary electrode to dissipate charges;

and 4, step 4: the yarn wound on the yarn withdrawing roller sequentially passes through the motor, the funnel, the fixing plate and the yarn guide hook and is fixed on the winding roller;

and 5: turning on a motor of the solution supply device and setting the moving speed of the filament plate;

step 6: turning on a high-voltage power supply to set spinning voltage, turning on an air compressor to set air pressure, and turning on a fan;

and 7: opening a controller to set the rotating speed of a funnel collector and the winding speed of a winding roller so as to ensure that a yarn guide hook reciprocates in a certain area;

and 8: the spinning solution jet is sprayed out from the surface of a spinning die head, and is stretched, refined and solidified into filaments under the dual actions of an electrostatic field and an air flow field. The fan helps to evaporate the solvent and maintain the humidity of the cabinet. After a stable triangular inverted cone is formed on the surface of the funnel collector, cutting the yarn from a yarn withdrawal roller, controlling the size of the electrostatic voltage and the angle and the size of circular blowing air sprayed by a spinning die head to ensure that the fiber deposition amount on the funnel collector is stable, ensuring that the nanofiber filamentation process and the yarn formation process of the yarn are carried out simultaneously, and if the nanofiber core-spun yarn is spun, the yarn does not need to be cut;

and step 9: and (4) after the nanofiber yarn prepared in the step (8) passes through the yarn guide hook, winding can be carried out along with the rotation of the winding roller, and the continuous collection of the yarn can be realized by replacing a yarn drum.

Compared with the prior art, the invention has the beneficial effects that: the continuous preparation device of the self-twisting nanofiber yarn formed in one step combines the advantages of electrostatic spinning and solution jet spinning, polymer jet flow is drawn, refined and solidified under the double effects of electrostatic force and circular blowing airflow to form a highly-oriented triangular inverted cone, and the inverted cone formed by the nanofibers is collected, twisted and stretched through a funnel collector and a winding device to prepare the nanofiber yarn with controllable twist and fineness.

The method reduces the electrostatic voltage and air pressure of solution fiber forming, has wide raw material applicability, simple operation and high yarn forming efficiency, particularly has good quality of the prepared pure nanofiber yarn, high orientation degree, uniform structure, large porosity and excellent mechanical property, can realize the application of the nanofiber in various fields, and is beneficial to further widening the application market of textiles.

Drawings

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

FIG. 2 is a front view of an electrostatic spinning of the present invention;

FIG. 3 is a schematic view of a spinning die;

description of reference numerals: 1. a spinning die head; 2. a die head bracket; 3. a die head inner needle; 4. a die head outer needle; 5. a gas delivery pipe; 6. a hopper collector; 7. an electrode; 8. a yarn withdrawing roller; 9. an electrode; 10. a fan; 11. a coupling; 12. an insulating plate; 13. a gear; 14. an air pump 15. a winding roller; 16. a yarn guide hook; 17. a fixing plate; 18. a nanofiber; 19. back taper of the nano fiber; 20. a nanofiber yarn; 21. an injector; (ii) a 22. Feeding a silk plate; 23. a lead screw; 24. a solution supply device; 25 electrostatic generator (positive); 26. electrostatic generators (negative); 27. and a controller.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the technical solutions of the present invention. The present invention is not limited to the embodiments described below, and all other embodiments obtained by those skilled in the art without any inventive step are within the scope of the present invention.

The invention aims to provide a device and a method for continuously preparing self-twisted electrostatic melt-blown nanofiber yarns, and aims to solve the problems of poor stability, uncontrollable yarn twist, poor yarn strength and the like in a yarn forming process. The device comprises a spinning unit, a collecting unit and a winding unit, and the using method comprises the following steps:

step 1: fixing the injector added with the spinning solution on a spinning plate, and connecting the injector with an inner needle of a spinning die head by using a liquid conveying pipe;

step 2: nesting and assembling the inner needle head and the outer needle head into a spinning die head which is arranged on a bracket, adjusting the distance of the spinning die head and setting the angle between the die heads;

and step 3: outer needle heads of the two spinning die heads are respectively connected with the anode and the cathode of a high-voltage power supply through wires, metal wires are respectively wound on the two die heads, and a certain length is reserved as an auxiliary electrode to dissipate charges;

and 4, step 4: the yarn wound on the yarn withdrawing roller sequentially passes through the motor, the funnel, the fixing plate and the yarn guide hook and is fixed on the winding roller;

and 5: turning on a motor of the solution supply device and setting the moving speed of the filament plate;

step 6: turning on a high-voltage power supply to set spinning voltage, turning on an air compressor to set air pressure, and turning on a fan;

and 7: opening a controller to set the rotating speed of a funnel collector and the winding speed of a winding roller so as to ensure that a yarn guide hook reciprocates in a certain area;

and 8: the spinning solution jet is sprayed out from the surface of a spinning die head, and is stretched, refined and solidified into filaments under the dual actions of an electrostatic field and an air flow field. The fan helps to evaporate the solvent and maintain the humidity of the cabinet. After a stable triangular inverted cone is formed on the surface of the funnel collector, cutting the yarn from a yarn withdrawal roller, controlling the size of the electrostatic voltage and the angle and the size of circular blowing air sprayed by a spinning die head to ensure that the fiber deposition amount on the funnel collector is stable, ensuring that the nanofiber filamentation process and the yarn formation process of the yarn are carried out simultaneously, and if the nanofiber core-spun yarn is spun, the yarn does not need to be cut;

and step 9: and (4) after the nanofiber yarn prepared in the step (8) passes through the yarn guide hook, winding can be carried out along with the rotation of the winding roller, and the continuous collection of the yarn can be realized by replacing a yarn drum.

The first embodiment is as follows: preparation of PAN pure nanofiber yarn

As shown in fig. 1, the present embodiment provides a continuous preparation apparatus of a self-twisted nanofiber yarn formed in one step, including a spinning unit, a collecting unit, and a winding unit. The spinning unit mainly comprises a solution supply device 24, a conjugate spinning die head 1, electrostatic high-voltage power supplies (25 and 26) and a compression air pump 14. FIG. 3 is a schematic structural diagram of a spinning die head, wherein the spinning die head 1 is formed by nesting an inner needle 3 and an outer needle of the die head, the two needles are not contacted with each other, and an annular gap is formed for air flow to pass through. The solution supply device 24 is connected with the inner needle 3 of the die head to supply the spinning solution, and the compressed air pump 14 is connected with the outer needle 4 of the die head to supply the auxiliary air flow. The two metal spinning die heads are respectively connected with the anode 25 and the cathode 26 of the electrostatic generator through cables.

The collecting unit comprises a motor 7 which is horizontally arranged, a through hole is formed in the center line of the motor 7, and the front end of the motor 7 is connected with the funnel collector 6 and drives the funnel to rotate. The vertical height of the funnel collector 6 is lower than the spinning die 1.

The winding unit comprises a winding roller 15, a yarn guide hook 16 and a fixing plate 17, wherein the winding roller 15 is connected with the motor 9 through a coupler 12; the yarn guide hook 15 is connected with the coupler 12 through a gear 13 and reciprocates along with the winding of the winding roller 15 on one side of the fixed plate 17. A circular through hole is arranged above the fixed plate 17 and is positioned on the same horizontal axis with the through holes of the funnel collector 6 and the motor 7. The collecting unit and the winding unit are fixed together on the insulating plate 11.

Optionally, the solution supply device 24 comprises a feeding plate 22, a lead screw 23, and an injector 21. The injector 21 fixed to the feed plate 22 is pressed by the rotation of the feed screw 23 to supply the spinning solution. The injector 21 is communicated with the inner needle 3 of the die head through a transfusion tube.

Optionally, the vertical height of the spinning die head 1 is higher than that of the funnel collector 6, the distance between the spinning die head and the funnel collector is adjustable, and the adjusting range is 10-20 cm.

Optionally, the spinning die head 1 is fixed on the support 2, the distance between the two die heads ranges from 5 cm to 20cm, and the angle ranges from 0 to 90 degrees.

Optionally, the two spinning die heads 1 are respectively wound with metal wires and extend out for a certain length to be used as auxiliary electrodes.

Optionally, a take-off roller 8 is mounted behind the hopper collector 6.

Optionally, the compression air pump 14 is an air compressor.

Optionally, the spinning unit comprises a fan 10 mounted at the manifold.

The embodiment provides a continuous preparation method of self-twisting pure nanofiber yarns, which specifically comprises the following steps:

step 1: preparing a PAN solution with the mass fraction of 8-16%, and stirring overnight by magnetic force to fully dissolve the PAN solution into the PAN spinning solution. Fixing an injector 21 added with spinning solution on a filament feeding plate 22, and connecting the injector 21 with the die head inner needle 3 by using a liquid conveying pipe;

step 2: nesting and assembling a die head inner needle 3 and a die head outer needle 4 into a spinning die head 1, installing the spinning die head 1 on a bracket 2, adjusting the distance between two spinning die heads, and setting the angle between the die heads;

and step 3: the two spinning die heads 1 are respectively connected with the anode 25 and the cathode 26 of the electrostatic generator through wires, metal wires are respectively wound on the two die heads, and a certain length is reserved as an auxiliary electrode to dissipate charges;

and 4, step 4: the yarn wound on the yarn withdrawing roller 8 sequentially passes through the motor 7, the funnel collector 6, the fixing plate 17 and the yarn guide hook 16 and is fixed on the winding roller 15;

and 5: opening the solution supply device 24 and setting the moving speed of the filament plate 22;

step 6: turning on the electrostatic generators (25, 26) to set spinning voltage, turning on the air compressor 14 to set air pressure, and turning on the fan 10;

and 7: the opening controller 27 sets the rotation speed of the hopper collector 6 and the winding speed of the winding roller 15 to ensure the yarn guide hook 16 to reciprocate in a certain area;

and 8: as shown in fig. 2, the spinning solution jet is ejected from the surface of the spinneret die head 1, and is stretched, thinned and solidified into the nanofibers 18 under the dual actions of the electrostatic field and the air flow field. The fan 10 helps to evaporate the solvent and maintain the humidity in the cabinet. After stable nanofiber back taper 20 is formed on the surface of the funnel collector 6, the yarn is cut off from the yarn withdrawing roller 8, the fiber deposition amount on the funnel collector is stable by controlling the size of electrostatic voltage and the angle and the size of circular air blown out by the spinning die head, the simultaneous proceeding of the nanofiber filamentation process and the yarn forming process of the yarn is ensured, and the nanofiber yarn 19 can be obtained.

And step 9: the nanofiber yarn 19 prepared in the step 8 can be wound along with the rotation of the winding roller 15 after passing through the fixing plate 17 and the yarn guide hook 16, and the continuous collection of the yarn is realized by replacing a bobbin.

The embodiment combines the advantages of electrostatic spinning and solution jet spinning, the polymer jet flow is drafted, thinned and solidified under the dual actions of electrostatic force and circular blowing airflow to form a highly-oriented triangular inverted cone, and the inverted cone edge formed by the nanofibers is collected, twisted and stretched by the funnel collector and the winding device to prepare the nanofiber yarn with controllable twist and fineness. The prepared pure nanofiber yarn has good quality, high orientation degree, uniform structure, large porosity and excellent mechanical property.

Example two: preparation of cotton/PAN nanofiber core-spun yarn

This example provides a continuous preparation method of nanofiber core spun yarn, and the structure of the device used is the same as that of the first example. The continuous preparation method of the nanofiber core-spun yarn comprises the following steps:

step 1: preparing a PAN solution with the mass fraction of 8-16%, and stirring overnight by magnetic force to fully dissolve the PAN solution into the PAN spinning solution. Fixing an injector 21 added with spinning solution on a filament feeding plate 22, and connecting the injector 21 with the die head inner needle 3 by using a liquid conveying pipe;

step 2: nesting and assembling a die head inner needle 3 and a die head outer needle 4 into a spinning die head 1, installing the spinning die head 1 on a bracket 2, adjusting the distance between two spinning die heads, and setting the angle between the die heads;

and step 3: the two spinning die heads 1 are respectively connected with the anode 25 and the cathode 26 of the electrostatic generator through wires, metal wires are respectively wound on the two die heads, and a certain length is reserved as an auxiliary electrode to dissipate charges;

and 4, step 4: the cotton yarn wound on the yarn withdrawing roller 8 sequentially passes through the motor 7, the funnel collector 6, the fixing plate 17 and the yarn guide hook 16 and is fixed on the winding roller 15;

and 5: opening the solution supply device 24 and setting the moving speed of the filament plate 22;

step 6: the electrostatic generators (25, 26) are turned on to set spinning voltage, the air compressor 14 is turned on to set air pressure, and the fan 10 is turned on.

And 7: the opening controller 27 sets the rotation speed of the hopper collector 6 and the winding speed of the winding roller 15 to ensure the yarn guide hook 16 to reciprocate in a certain area;

and 8: as shown in fig. 2, the spinning solution jet is ejected from the surface of the spinneret die head 1, and is stretched, thinned and solidified into the nanofibers 18 under the dual actions of the electrostatic field and the air flow field. The fan 10 helps to evaporate the solvent and maintain the humidity in the cabinet. By controlling the electrostatic voltage and the angle and the size of the circular air blown by the spinning die head, the fiber deposition amount on the funnel collector is stable, the simultaneous proceeding of the nanofiber filamentation process and the yarn forming process of the yarn is ensured, and the nanofiber core-spun yarn 19 can be obtained.

And step 9: and (3) the core-spun yarn prepared in the step (8) passes through the fixing plate 17 and the yarn guide hook 16 and then can be wound along with the rotation of the winding roller 15, and the yarn drum is replaced to realize the continuous collection of the yarn.

The method reduces the electrostatic voltage and air pressure for solution fiber forming, and has the advantages of wide raw material applicability, simple operation and high yarn forming efficiency. Different nano-fiber core-spun yarns can be prepared by replacing the core yarns and the spinning solution, the prepared core-spun yarns are good in quality, high in orientation degree, uniform in structure and excellent in mechanical property, the application of nano-fibers in various fields can be realized, and the application market of textiles can be further widened.