A preparation device and method for continuous carbon fiber thermoplastic strip

Abstract

The present invention discloses a preparation device and method for continuous carbon fiber thermoplastic strips, wherein the preparation device for the continuous carbon fiber thermoplastic strips comprises a yarn unwinding unit, an impregnation unit, a hardening unit and a traction and winding unit which are sequentially arranged; the yarn unwinding unit is used to place a number of whole rolls of carbon fiber; the impregnation unit is used to ply the yarns released by the yarn unit and impregnate them with glue, squeeze glue and shape them; the hardening unit is used to dry and harden the carbon fiber thermoplastic strips after passing through the impregnation unit. The present invention sequentially arranges a yarn unwinding unit, an impregnation unit, a hardening unit and a traction and winding unit to prepare soft and fluffy carbon fibers into continuous carbon fiber thermoplastic strips. The continuous carbon fiber thermoplastic strips not only improve the interfacial bonding performance between carbon fiber and thermoplastic resin, but also have the hardening and bundling property of yarn bundles, meet the processing requirements of thermoplastic resin, thereby greatly improving the performance of carbon fiber thermoplastic composite materials, and are easy to process and produce carbon fiber thermoplastic composite materials, thereby improving efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of composite material production, and particularly to a device and method for preparing continuous carbon fiber thermoplastic strips. Background Art

[0002] Carbon fiber has properties such as high strength, high modulus, high temperature resistance, friction resistance, heat conduction, electrical conductivity, and corrosion resistance. Therefore, it can be used as a reinforcing material to be compounded with resin to manufacture high-performance composite materials. Since the composite material reinforced by continuous carbon fiber has higher strength and modulus, its products can be applied to many high-end fields, such as the fields of automobiles, sports, aerospace, etc. However, at present, most carbon fiber composite materials are thermosetting matrices, and thermoplastic resins have also become a research hotspot due to their advantages such as good toughness and recyclability.

[0003] There are usually two difficulties in the preparation of carbon fiber thermoplastic composite materials by compounding carbon fiber with thermoplastic resin. On the one hand, for carbon fiber reinforced thermoplastic resin to better exert its performance advantages, the interfacial bonding between the fiber and the resin must be improved. Good interfacial bonding is the basis for improving the performance of carbon fiber thermoplastic composites. Usually, an effective method to improve interfacial bonding is to perform sizing treatment of thermoplastic slurry on the fiber surface. After sizing, the interfacial bonding performance between carbon fiber and resin is significantly improved. On the other hand, carbon fiber is soft and fluffy, which is not conducive to metering and processing production with thermoplastic resin, and it needs to be hardened and bundled.

[0004] Therefore, it is necessary to develop a device and method for preparing carbon fiber thermoplastic strips that can not only solve the problem of interfacial bonding between carbon fiber and thermoplastic resin, but also harden and bundle carbon fiber tows, meet the processing requirements of thermoplastic resin, and are low-cost and suitable for industrial production. Summary of the Invention

[0005] The purpose of the present invention is to provide a device and method for preparing continuous carbon fiber thermoplastic strips in view of the deficiencies of the prior art.

[0006] The technical solution of the present invention is: a device for preparing continuous carbon fiber thermoplastic strips, including a yarn feeding unit, an impregnation unit, a hardening unit, and a traction and winding unit arranged in sequence; the yarn feeding unit is used to place a plurality of whole rolls of carbon fiber; the impregnation unit is used to combine and impregnate the glue on the yarn released by the yarn unit, extrude the glue and shape it; the hardening unit is used to dry and harden the carbon fiber thermoplastic strip after passing through the impregnation unit; the traction and winding unit is used to cool and wind the dried and hardened carbon fiber thermoplastic strip.

[0007] The yarn feeding unit includes a winding rack and a plurality of winding shafts evenly distributed on the winding rack.

[0008] The impregnation unit includes a glue storage barrel and a number of impregnation barrels communicated with the glue storage barrel; one end of the impregnation barrel opposite to the yarn feeding unit is provided with a wire inlet, and the end far from the wire inlet is provided with a wire outlet.

[0009] The wire inlet of the impregnation barrel is in an inverted conical shape.

[0010] The wire outlet is a gradually changing conical orifice film, the conical orifice extends outward, and the orifice die is circular.

[0011] The hardening unit includes a base and a number of far-infrared generating devices evenly distributed on the base; a layer of glass is laid on the far-infrared generating devices.

[0012] The traction and winding unit includes a base and a traction assembly and a winding assembly sequentially arranged on the base; the traction assembly includes a traction roller and a pressure roller movably arranged above the traction roller, and the pressure between the pressure roller and the traction roller is adjustable; the winding assembly includes a winding frame and a plurality of winding rollers rotatably connected to the winding frame from top to bottom.

[0013] A circulating cooling water flow channel is arranged inside the pressure roller.

[0014] A method for preparing a continuous carbon fiber thermoplastic strip by using the above preparation device is characterized by comprising the following steps:

[0015] S1: Unwind the coiled yarn bundle from the yarn feeding unit and carry out doubling.

[0016] S2: Pass the doubled yarn bundle through the impregnation barrel to impregnate the thermoplastic slurry, pass through the gradually changing conical orifice film at the outlet, extrude the excess slurry, control the resin content, and shape the yarn bundle.

[0017] S3: Pass the impregnated yarn bundle through the glass surface of the hardening unit to carry out dehydration and hardening.

[0018] S4: Wind the dehydrated and hardened yarn bundle through the traction and winding unit to obtain a continuous carbon fiber thermoplastic strip.

[0019] By adopting the above technical solutions, the present invention has the following beneficial effects: The present invention sequentially arranges a yarn feeding unit, an impregnation unit, a hardening unit and a traction and winding unit to prepare soft and fluffy carbon fibers into continuous carbon fiber thermoplastic strips. The continuous carbon fiber thermoplastic strips not only improve the interfacial bonding performance between the carbon fibers and the thermoplastic resin, but also have the property of hardening and bundling the yarn bundle, meeting the processing requirements of the thermoplastic resin, thereby greatly improving the performance of the carbon fiber thermoplastic composite material, and being easy to process and produce the carbon fiber thermoplastic composite material, improving the efficiency.

[0020] (2) The yarn feeding unit of the present invention includes a unwind rack and a number of unwind shafts evenly distributed on the unwind rack, so as to facilitate the placement of a large number of coiled carbon fibers.

[0021] (3) The present invention provides a number of impregnation barrels, which can form several yarn bundles simultaneously, improving the production efficiency.

[0022] (4) The inlet of the impregnation barrel of the present invention is in an inverted conical shape, which can cause multiple yarn bundles to converge and enter the barrel.

[0023] (5) The outlet of the present invention is a gradually changing conical orifice film, the conical orifice extends outward, and the orifice die is circular, which can extrude the excess slurry, control the gum content, and shape the yarn bundle.

[0024] (6) The hardening unit of the present invention uses a number of far-infrared generating devices, which can be individually controlled for each one. By switching the number of far-infrared generating devices, the drying speed can be controlled.

[0025] (7) The traction assembly of the present invention uses a traction roller and a pressure roller movably arranged above the traction assembly, which can adjust the pressure between the pressure roller and the traction roller at any time. At the same time, a number of winding rollers are provided, and the multiple winding rollers wind synchronously, further improving the production efficiency.

[0026] (8) The inside of the pressure roller of the present invention is provided with a circulating cooling water flow channel, which can cool the hardened yarn bundle. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to make the content of the present invention easier to be clearly understood, the following further details the present invention according to specific embodiments in conjunction with the drawings.

[0028] Figure 1 It is a schematic structural diagram of the present invention.

[0029] Figure 2 It is a schematic structural diagram of the impregnation unit of the present invention.

[0030] Figure 3 It is a schematic structural diagram of the hardening unit of the present invention.

[0031] Figure 4 It is a schematic structural diagram of the traction and winding unit of the present invention.

[0032] The reference numerals in the drawings are:

[0033] Yarn feeding unit 1, unwinding rack 1-1, unwinding shaft 1-2, impregnation unit 2, glue storage barrel 2-1, impregnation barrel 2-2, inlet 2-3, outlet 2-4, hardening unit 3, base 3-1, far-infrared generating device 3-2, glass 3-3, traction and winding unit 4, base 4-1, traction roller 4-2, pressure roller 4-3, winding rack 4-4, winding roller 4-5. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] (Example 1)

[0035] See Figures 1 to 4 Figures 1 to 4 , a preparation device for a continuous carbon fiber thermoplastic strip according to this embodiment includes a yarn feeding unit 1, an impregnation unit 2, a hardening unit 3, and a traction and winding unit 4 arranged in sequence; the yarn feeding unit 1 is used to place a number of whole rolls of carbon fiber; the impregnation unit 2 is used to combine and impregnate the glue on the yarn released by the yarn unit, extrude the glue and shape it; the hardening unit 3 is used to dry and harden the carbon fiber thermoplastic strip after passing through the impregnation unit 2; the traction and winding unit 4 is used to cool and wind the dried and hardened carbon fiber thermoplastic strip.

[0036]

[0036] Furthermore, the yarn feeding unit 1 includes a winding rack 1-1 and a number of winding shafts 1-2 evenly distributed on the winding rack 1-1, which can place a large number of whole rolls of carbon fiber and improve production efficiency.

[0037]

[0037] Furthermore, the impregnation unit 2 includes a glue storage barrel 2-1 and a number of impregnation barrels 2-2 communicated with the glue storage barrel 2-1; one end of the impregnation barrel 2-2 opposite to the yarn feeding unit 1 is provided with an inlet 2-3, and the end far from the inlet 2-3 is provided with an outlet 2-4. The glue storage barrel 2-1 has the function of sealing and storing the thermoplastic slurry. A pressure regulator is provided at the inlet of the glue storage barrel 2-1. Through the operation of the pressure regulator, a constant micro-negative pressure is maintained in the glue storage barrel 2-1 as the slurry decreases. Maintaining a micro-negative pressure in the glue storage barrel 2-1 can prevent the internal slurry from flowing out too much, and the micro-negative pressure can easily further disperse the fiber filaments in the impregnation barrel, playing a role in uniform impregnation.

[0038]

[0038] Furthermore, the inlet 2-3 of the impregnation barrel 2-2 is in an inverted conical shape, which can enable multiple yarn bundles to converge and enter the barrel.

[0039]

[0039] Furthermore, the outlet 2-4 is a gradually changing conical orifice film, the conical orifice extends outward, and the orifice die is circular, which can extrude the excess slurry, control the glue content, and shape the yarn bundle.

[0040]

[0040] Furthermore, the hardening unit 3 includes a base 3-1 and a number of far-infrared generating devices 3-2 evenly distributed on the base 3-1; a layer of glass 3-3 is laid on the far-infrared generating devices 3-2, which can be individually controlled for each one. By switching the number of far-infrared generating devices, the drying speed can be controlled.

[0041] Further, the traction and winding unit 4 includes a base 4-1, a traction assembly and a winding assembly sequentially arranged on the base 4-1; the traction assembly includes a traction roller 4-2 and a pressure roller 4-3 movably arranged above the traction roller 4-2, and the pressure between the pressure roller 4-3 and the traction roller 4-2 is adjustable. The pressure roller 4-3 is slidably connected to the base 4-1 and its height is adjusted by a telescopic cylinder; the winding assembly includes a winding frame 4-4 and a plurality of winding rollers 4-5 rotatably connected to the winding frame 4-4 from top to bottom. To facilitate automatic winding, a cutting mechanism for cutting the thermoplastic strip is also provided on the base 4-1.

[0042] Further, a circulating cooling water flow channel is provided inside the pressure roller 4-3 to facilitate the cooling of the thermoplastic strip.

[0043] A method for preparing a continuous carbon fiber thermoplastic strip using the above preparation device, characterized by comprising the following steps:

[0044] S1: Unroll the wound yarn bundle from the yarn feeding unit 1 and carry out doubling.

[0045] S2: Pass the doubled yarn bundle through the impregnation tank 2-2 to impregnate with thermoplastic slurry, and extrude the excess slurry through a tapered die at the outlet, control the resin content, and shape the yarn bundle.

[0046] S3: Pass the impregnated yarn bundle through the surface of the glass 3-3 of the hardening unit 3 for dehydration and hardening.

[0047] S4: Wind the dehydrated and hardened yarn bundle through the traction and winding unit 4 to obtain a continuous carbon fiber thermoplastic strip.

[0048] In this embodiment, the yarn feeding unit 1, the impregnation unit 2, the hardening unit 3 and the traction and winding unit 4 are sequentially arranged to prepare soft and fluffy carbon fibers into continuous carbon fiber thermoplastic strips. The continuous carbon fiber thermoplastic strips not only improve the interfacial bonding performance between carbon fibers and thermoplastic resins, but also have the property of hardening and bundling of the yarn bundle, meeting the processing requirements of thermoplastic resins, thus greatly improving the performance of carbon fiber thermoplastic composites and being easy to process and produce carbon fiber thermoplastic composites, improving efficiency.

[0049] The specific embodiments described above have further elaborated on the purpose, technical solution and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A device for preparing continuous carbon fiber thermoplastic strips, characterized in that: The invention comprises a yarn unwinding unit (1), an impregnation unit (2), a hardening unit (3) and a traction and winding unit (4) which are arranged in sequence; the yarn unwinding unit (1) is used to place a plurality of full rolls of carbon fiber; the impregnation unit (2) is used to fold and impregnate the yarn unwinding from the yarn unit, squeeze the glue and shape the yarn; the hardening unit (3) is used to dehydrate, dry and harden the carbon fiber thermoplastic strip after passing through the impregnation unit (2); the traction and winding unit (4) is used to cool and wind the carbon fiber thermoplastic strip after dehydration, drying and hardening; the impregnation unit (2) comprises a glue storage barrel (2-1) and a plurality of impregnation barrels (2-2) connected to the glue storage barrel (2-1); the impregnation barrels (2-2) are arranged relative to the yarn unwinding unit (1). A wire inlet (2-3) is provided at one end, and a wire outlet (2-4) is provided at the end away from the wire inlet (2-3); the wire inlet (2-3) of the impregnation barrel (2-2) is in an inverted cone shape; the wire outlet (2-4) is a gradually changing cone-shaped die, the cone mouth extends outward, and the die is circular; the glue storage barrel (2-1) has the function of sealing and storing thermoplastic slurry; a pressure regulator is provided at the inlet of the glue storage barrel (2-1); through the operation of the pressure regulator, a constant micro-negative pressure is maintained in the glue storage barrel (2-1) as the slurry decreases; the micro-negative pressure prevents the slurry inside the glue storage barrel (2-1) from flowing out too much, and the micro-negative pressure makes it easy for the fiber bundles to be further dispersed in the impregnation barrel, so that the fiber bundles are evenly impregnated.

2. The device for preparing a continuous carbon fiber thermoplastic strip according to claim 1, characterized in that: The yarn unwinding unit (1) comprises an unwinding frame (1-1) and a plurality of unwinding shafts (1-2) evenly distributed on the unwinding frame (1-1).

3. The device for preparing a continuous carbon fiber thermoplastic strip according to claim 1, characterized in that: The hardening unit (3) comprises a base (3-1) and a plurality of far-infrared generating devices (3-2) evenly distributed on the base (3-1); a layer of glass (3-3) is laid on the far-infrared generating devices (3-2).

4. The device for preparing a continuous carbon fiber thermoplastic strip according to claim 1, characterized in that: The traction and winding unit (4) comprises a base (4-1) and a traction assembly and a winding assembly which are arranged on the base (4-1) in sequence; the traction assembly comprises a traction roller (4-2) and a pressure roller (4-3) movably arranged above the traction roller (4-2), and the pressure between the pressure roller (4-3) and the traction roller (4-2) is adjustable; the winding assembly comprises a winding frame (4-4) and a plurality of winding rollers (4-5) which are rotatably connected to the winding frame (4-4) from top to bottom.

5. The device for preparing a continuous carbon fiber thermoplastic strip according to claim 4, characterized in that: A circulating cooling water channel is provided inside the pressure roller (4-3).

6. A method for preparing continuous carbon fiber thermoplastic strips using the preparation device according to claim 3, characterized in that: The following steps are involved: S1: releasing the rolled yarn bundle from the yarn releasing unit (1) and performing stranding; S2: passing the stranded yarn bundle through an impregnation barrel (2-2) to be impregnated with thermoplastic slurry, and passing through a gradual tapered die at the outlet to squeeze out excess slurry, control the glue content, and complete the shaping of the yarn bundle; S3: passing the impregnated yarn bundle through the glass (3-3) surface of the hardening unit (3) for dehydration and hardening; S4: The dehydrated and hardened yarn bundle is wound up by a traction winding unit (4) to obtain a continuous carbon fiber thermoplastic strip.

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