Device for preparing continuous fiber reinforced thermoplastic resin composite prepreg wire

Abstract

The invention discloses a device for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire rod, and belongs to the technical field of composite material manufacturing. The device comprises a continuous wire releasing system, a fiber pretreatment system, a resin impregnation system, a solution volatilization system, a wire shaping system and a post-treatment system. In the preparation process of the continuous fiber reinforced thermoplastic resin prepreg wire, the thermoplastic resin in the prepreg wire is fully wetted and uniformly distributed through the continuous activation treatment of the fiber pretreatment system and the homogenization extrusion impregnation process of the resin impregnation system. And continuous preparation of the 3D printing continuous fiber reinforced thermoplastic resin prepreg wire with high fiber content and low porosity can be realized through subsequent processes such as efficient volatilization of the solution volatilization system and multi-level pultrusion shaping of the shaping system. The mechanical property and the production efficiency of the 3D printing continuous fiber reinforced thermoplastic resin prepreg wire and the composite material thereof can be obviously enhanced, and meanwhile, the manufacturing scheme is stable and reliable.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite material manufacturing, and particularly relates to a device for preparing continuous fiber reinforced thermoplastic resin composite prepreg wires. Background Art

[0002] Continuous fiber reinforced thermoplastic composites (CFRTC) are widely used as structural components in fields such as aerospace, civil engineering, transportation, and energy due to their advantages in specific strength, thermal stability, corrosion resistance, fatigue resistance, recyclability, and impact toughness. Compared with traditional manufacturing technologies such as hot pressing, automatic lamination, and extrusion molding, 3D printing CFRTC, as one of the most promising advanced technologies in the field of rapid manufacturing, has outstanding advantages in terms of processability, material utilization rate, design freedom, manufacturing speed, and moldless integrated molding of complex structures. It has created important opportunities for the further development of high-strength, multi-material integration, low-cost, and high-throughput manufacturing of complex-structured composite materials.

[0003] 3D printing CFRTC has been realized through two methods: in-situ impregnation and prepreg wires. The former is to send fiber bundles and thermoplastic resin into the nozzle simultaneously. Subsequently, the thermoplastic melt impregnates the continuous tow and deposits together to manufacture the corresponding structure. However, the above method is only applicable to general resins with low viscosity and cannot achieve the effective combination of continuous fibers and high-temperature, high-viscosity engineering polymers. Therefore, continuous fiber reinforced thermoplastic resin prepreg wires suitable for 3D printing have been developed. Although this technology has disadvantages in terms of cost and efficiency, it can effectively combine engineering plastics with continuous fibers. In addition, CFRTC printed based on the latter technology has higher mechanical strength and interfacial strength. In short, this method is expected to become the mainstream method for 3D printing CFRTC. Therefore, the preparation process and properties of prepreg wires determine the basic properties of 3D printing CFRTC.

[0004] Currently, the production of prepreg wires mainly uses the melt impregnation method, that is, the molten thermoplastic resin is filled into the impregnation mold through a screw extruder, and the molten resin is impregnated into the continuous fiber by extrusion pressure. This technology has the advantages of environmental friendliness, mature preparation method, and low porosity. For example, Chinese patents ZL202411178500.4 and ZL202110811076.2, the common feature of the two is the development of equipment based on melt impregnation for the production of continuous fiber reinforced thermoplastic prepreg wires. However, due to the limited adjustable range of the viscosity of engineering resins, problems such as large-area fracture of single fibers and high porosity are prone to occur during the preparation of high-fiber-content wires by melt impregnation, and the thermal decomposition caused by the resin being in a high-temperature environment for a long time also seriously affects the interfacial bonding and mechanical strength between continuous fibers and thermoplastic resins.

[0005] Therefore, on the premise of ensuring a high fiber content in the prepreg wire, it is a difficult problem and an urgent issue to be solved for the structural design and process departments to achieve the uniform distribution and impregnation of continuous fibers and thermoplastic resin and the low porosity of the prepreg wire, so as to improve the mechanical properties of the prepreg wire and 3D printed composite materials and promote them to a broader application field. Summary of the Invention

[0006] Aiming at the problem that under the premise of a high fiber content in the current continuous fiber reinforced thermoplastic prepreg wire, the uniform impregnation of continuous fibers and thermoplastic resin cannot be achieved and the porosity of the prepreg wire and 3D printed composite materials cannot be reduced, the present invention provides a device for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire.

[0007] To solve the above technical problems, the present invention adopts the following technical solutions:

[0008] A device for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire, the device comprising:

[0009] A continuous wire feeding system, placed at the forefront of the entire device, comprising a wire feeding unit and a tension unit, for continuously feeding the fiber tow at a constant speed and tension;

[0010] A fiber pretreatment system, located behind the continuous wire feeding system, comprising a fiber spreading unit and a preheating unit, for activating the physical and chemical properties of the continuous fiber;

[0011] A resin impregnation system, located behind the fiber pretreatment system, for impregnating the continuous fiber with a thermoplastic resin sizing solution;

[0012] A solution volatilization system, located behind the resin impregnation system, for volatilizing the solution of the continuous fiber containing the thermoplastic resin solution;

[0013] A shaping system, located behind the solution volatilization system, for fixing the roundness shape of the composite prepreg wire and optimizing the fiber distribution;

[0014] A post-treatment system, located behind the shaping system, comprising a cooling unit and a winding unit, for performing subsequent treatment and winding of the shaped prepreg wire.

[0015] Furthermore, the wire feeding unit is a constant speed wire feeder and is connected to the wire feeding shaft to ensure that the continuous fiber is impregnated with resin, the solution is volatilized, and the wire is shaped at a continuous and stable speed.

[0016] Further, the tension unit includes a tension sensor and a tension controller, both of which are controlled and driven by a PLC circuit and a servo motor, so as to prevent problems such as uncontrollable material winding and deformation of continuous fibers and prepreg wires caused by too small tension and prevent continuous fiber breakage caused by too large tension, thereby ensuring the stable and continuous production of continuous fiber reinforced thermoplastic resin prepreg wires and product quality.

[0017] Further, the fiber spreading unit includes a positioning guide roller, a fiber spreading unit outlet channel, a vacuum generator, and an air duct. The continuous fibers passing through the positioning guide roller are dispersed perpendicular to the air flow direction in the air flow generated by the vacuum generator through the air duct, realizing the flat and uniform broadening of the fiber bundle to improve the penetration characteristics of thermoplastic resin into continuous fibers. The fiber spreading unit outlet channel adopts a rectangular channel, and its aspect ratio is 30:1 to 50:1, maintaining the fiber spreading width of continuous fibers to reduce the porosity of the subsequent prepreg wire.

[0018] Further, the preheating unit includes a preheating unit inlet channel, a preheating unit heat preservation device, a preheating unit temperature measuring device, a preheating unit temperature control device, and a preheating unit outlet channel. Activating the physical and chemical properties of continuous fibers can improve the adsorption capacity for thermoplastic resin to improve the impregnation effect of prepreg wires and increase the production quality and efficiency of prepreg wires. Both the preheating unit inlet channel and the preheating unit outlet channel adopt rectangular channels, and their aspect ratios are both 30:1 to 50:1, avoiding the impact of the continuous fibers spread to the specified width on the product quality of the subsequent prepreg wires after retraction.

[0019] Further, the resin impregnation system is an impregnation tank, specifically including a resin impregnation system inlet channel, a guide roller, a sealed heat preservation tank, a pressure rubber roller, a scraping rubber roller, a resin impregnation system outlet channel, a resin impregnation system temperature measuring device, and a resin impregnation system heat preservation device;

[0020] The sealed heat preservation tank is used to reduce the adverse effects caused by the increase in the viscosity of the impregnating solution due to solvent volatilization. Both the resin impregnation system inlet channel and the resin impregnation system outlet channel adopt rectangular channels. The aspect ratio of the resin impregnation system inlet channel is 30:1 to 50:1, which is used to increase the impregnation area of the continuous fiber bundle to reduce the porosity of the prepreg tape. The aspect ratio of the resin impregnation system outlet channel is 20:1 - 40:1, which is used to expand the volatilization area of the prepreg tape, improve the volatilization effect and efficiency of the solvent in the prepreg tape to reduce the probability of thermoplastic resin degradation and ensure the performance of the prepreg wire.

[0021] The guide roller is located above the impregnation tank and is arranged close to the resin impregnation system inlet channel side, ensuring that the continuous fibers passing through the resin impregnation system inlet channel enter the predetermined impregnation position to ensure the uniform and stable mechanical properties of the prepreg wire.

[0022] The described sizing roller is located above the sizing bath, parallel to the guiding roller, and is arranged close to the side of the resin impregnation system export channel; it is used to remove the excess sizing liquid in the fiber bundle to increase the volume content of continuous fibers in the prepreg wire and the uniformity of mechanical properties.

[0023] The described pressure roller is located below the sizing bath and is between the guiding roller and the sizing roller; it is used to increase the impregnation pressure to enhance the penetration and impregnation of the thermoplastic resin into the continuous fibers and reduce the porosity of the prepreg wire.

[0024] Furthermore, the temperature measuring device and heat preservation device of the resin impregnation system are located at the bottom of the sizing bath, which is used to keep the viscosity of the sizing liquid in the resin impregnation system constant to ensure the quality stability of the prepreg wire under different environments.

[0025] Furthermore, the solution volatilization system includes a solution volatilization system import channel, a solution volatilization system heat preservation device, a solution volatilization system temperature measuring device, a solution volatilization system temperature control device, a solution volatilization system export channel, and a nitrogen protection device;

[0026] Both the solution volatilization system import channel and the solution volatilization system export channel adopt rectangular channels, and the aspect ratio of their length to width is 20:1 to 40:1, which is used to expand the specific surface area of the composite strip to improve the solvent volatilization effect and efficiency, so as to increase the interfacial bonding strength between the continuous fibers and the thermoplastic resin and the continuous production efficiency;

[0027] The described nitrogen protection device includes a nitrogen storage device, a nitrogen supply valve, and a nitrogen discharge valve, which is used to prevent the problems of thermoplastic resin degradation and steam corrosion of the device during the solvent volatilization process.

[0028] Furthermore, the shaping system includes a first-stage temperature control device, a second-stage temperature control device, a third-stage temperature control device, a first-stage shaping die, a second-stage shaping die, a third-stage shaping die, a first-stage temperature measuring device (77), a second-stage temperature measuring device, and a third-stage temperature measuring device;

[0029] The first-stage shaping die, the second-stage shaping die, and the third-stage shaping die are arranged in sequence from the continuous fiber inlet side to the continuous fiber outlet side of the shaping system;

[0030] The first-stage temperature control device and the first-stage temperature measuring device are respectively arranged on the upper and lower parts of the first-stage shaping die; similarly, the second-stage temperature control device and the second-stage temperature measuring device are respectively arranged on the upper and lower parts of the second-stage shaping die; the third-stage temperature control device and the third-stage temperature measuring device are respectively arranged on the upper and lower parts of the third-stage shaping die.

[0031] Furthermore, the part of the first-stage shaping die in contact with the cross-section of the prepreg strip adopts a rectangular channel, and the aspect ratio of its length to width is 15:1 - 30:1, and the other end of the channel adopts an oval channel, and the aspect ratio of its length to width is 8:1 to 20:1;

[0032] The contact part between the described Class II sizing die and the cross-section of the prepreg wire adopts an oval-shaped channel, with an aspect ratio of 4:1 to 10:1. The other end of the channel adopts an oval-shaped channel, with an aspect ratio of 2:1 to 4:1;

[0033] The contact part between the described Class III sizing die and the cross-section of the prepreg wire adopts a circular channel, with a diameter of 0.40 - 0.90 mm. The other end adopts a circular channel, with a diameter of 0.30 - 0.80 mm.

[0034] Compared with the prior art, the present invention has the following advantages:

[0035] The device for preparing continuous fiber-reinforced thermoplastic resin composite prepreg wire of the present invention effectively solves the problem that continuous fiber-reinforced thermoplastic composites are difficult to have both a high fiber content and a low porosity. And under the condition of ensuring the production efficiency and quality of the prepreg wire, it eliminates the adverse effects of a large number of pores in the prepreg wire with a high fiber content. The equipment of the present invention only requires a relatively simple resin impregnation system and a solution volatilization system to realize the preparation of continuous fiber-reinforced thermoplastic composite prepreg wire with both a high fiber content and a low porosity, providing a reliable and stable technical solution for the manufacture of high-performance prepreg wire and its 3D printing composites. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0037] Figure 1 It is a schematic diagram of the overall device of the present invention;

[0038] Figure 2 It is a sectional view of the fiber spreading unit;

[0039] Figure 3 It is a sectional view of the preheating unit;

[0040] Figure 4 It is a sectional view of the resin impregnation system;

[0041] Figure 5 It is a sectional view of the solution volatilization system;

[0042] Figure 6 It is a sectional view of the wire sizing system.

[0043] Reference numerals: 1. wire feeding unit; 2. tension unit; 3. fiber spreading unit; 4. preheating unit; 5. resin impregnation system; 6. solution volatilization system; 7. shaping system; 8. cooling unit; 9. winding unit;

[0044] 31. positioning guide roller; 32. fiber spreading unit outlet channel; 33. vacuum generator; 34. air duct;

[0045] 41. preheating unit inlet channel; 42. preheating unit heat preservation device; 43. preheating unit temperature measuring device; 44. preheating unit temperature control device; 45. preheating unit outlet channel;

[0046] 51. resin impregnation system inlet channel; 52. guide roller; 53. sealed heat preservation tank; 54. rubber pressing roller; 55. rubber scraping roller; 56. resin impregnation system outlet channel; 57. resin impregnation system temperature measuring device; 58. resin impregnation system heat preservation device;

[0047] 61. solution volatilization system inlet channel; 62. solution volatilization system heat preservation device; 63. solution volatilization system temperature measuring device; 64. solution volatilization system temperature control device; 65. solution volatilization system outlet channel; 66. nitrogen protection device;

[0048] 71. Grade I temperature control device; 72. Grade II temperature control device; 73. Grade III temperature control device; 74. Grade I shaping die; 75. Grade II shaping die; 76. Grade III shaping die; 77. Grade I temperature measuring device; 78. Grade II temperature measuring device; 79. Grade III temperature measuring device. Detailed implementation manners

[0049] To deeply understand the present invention, we will describe it comprehensively and meticulously. However, the present invention has multiple implementation manners and is not limited to the specific examples listed herein. The presentation of these examples aims to deepen the comprehensive understanding of the disclosed content of the present invention.

[0050] A device for preparing continuous fiber reinforced thermoplastic resin composite prepreg wire, the device comprising:

[0051] A continuous wire feeding system, placed at the forefront of the entire device, comprising a wire feeding unit 1 and a tension unit 2, for continuously feeding a fiber filament bundle at a constant speed and tension;

[0052] A fiber pretreatment system, located behind the continuous wire feeding system, comprising a fiber spreading unit 3 and a preheating unit 4, for activating the physical and chemical properties of continuous fibers;

[0053] A resin impregnation system 5, located behind the fiber pretreatment system, for impregnating continuous fibers with a thermoplastic resin sizing solution;

[0054] The solution volatilization system 6 is located behind the resin impregnation system 5 and is used for volatilizing the solution of the continuous fiber containing the thermoplastic resin solution;

[0055] The shaping system 7 is located behind the solution volatilization system 6 and is used for fixing the roundness shape of the composite prepreg wire and optimizing the fiber distribution;

[0056] The post-treatment system is located behind the shaping system 7 and includes a cooling unit 8 and a winding unit 9, which are used for performing subsequent treatment and winding of the shaped prepreg wire.

[0057] Furthermore, the wire feeding unit 1 is a constant-speed wire feeder and is connected to the wire feeding shaft to ensure that the continuous fiber undergoes resin impregnation, solution volatilization, and wire shaping at a continuous and stable speed.

[0058] Furthermore, the tension unit 2 includes a tension sensor and a tension controller, and both the tension sensor and the tension controller are controlled and driven by a PLC circuit and a servo motor.

[0059] Furthermore, the fiber spreading unit 3 includes a positioning guide roller 31, a fiber spreading unit outlet channel 32, a vacuum generator 33, and an air duct 34; the continuous fiber passing through the positioning guide roller 31 is dispersed perpendicular to the air flow direction in the air flow generated by the vacuum generator 33 through the air duct 34, realizing the flat and uniform broadening of the fiber bundle to improve the penetration characteristics of the thermoplastic resin into the continuous fiber; the fiber spreading unit outlet channel 32 adopts a rectangular channel, and its aspect ratio is 30:1 to 50:1, maintaining the fiber spreading width of the continuous fiber to reduce the porosity of the subsequent prepreg wire.

[0060] Furthermore, the preheating unit 4 includes a preheating unit inlet channel 41, a preheating unit heat preservation device 42, a preheating unit temperature measuring device 43, a preheating unit temperature control device 44, and a preheating unit outlet channel 45; both the preheating unit inlet channel 41 and the preheating unit outlet channel 45 adopt rectangular channels, and their aspect ratios are both 30:1 - 50:1, avoiding the continuous fiber that has been spread to the specified width from retracting and affecting the product quality of the subsequent prepreg wire.

[0061] Furthermore, the resin impregnation system 5 is an impregnation tank, specifically including a resin impregnation system inlet channel 51, a guide roller 52, a sealed heat preservation tank 53, a pressure rubber roller 54, a scraping rubber roller 55, a resin impregnation system outlet channel 56, a resin impregnation system temperature measuring device 57, and a resin impregnation system heat preservation device 58;

[0062] The described sealed heat-insulating tank 53 is used to reduce the adverse effects caused by the increase in the viscosity of the impregnating solution due to solvent volatilization; both the resin impregnation system inlet channel 51 and the resin impregnation system outlet channel 56 adopt rectangular channels; the aspect ratio of the resin impregnation system inlet channel 51 is 30:1 to 50:1, which is used to increase the impregnation area of the continuous tow to reduce the porosity of the prepreg; the aspect ratio of the resin impregnation system outlet channel 56 is 20:1 - 40:1, which is used to expand the volatilization area of the prepreg strip, improve the volatilization effect and efficiency of the solvent in the prepreg strip to reduce the probability of thermoplastic resin degradation and ensure the performance of the prepreg wire;

[0063] The described guide roller 52 is located above the impregnating tank and is arranged close to one side of the resin impregnation system inlet channel 51; it ensures that the continuous fibers passing through the resin impregnation system inlet channel 51 enter the predetermined impregnation position to ensure the uniform stability of the mechanical properties of the prepreg wire;

[0064] The described sizing roller 55 is located above the impregnating tank, parallel to the guide roller 52, and is arranged close to one side of the resin impregnation system outlet channel 56; it is used to remove the excess sizing agent in the fiber bundle to increase the volume content of the continuous fibers in the prepreg wire and the uniformity of the mechanical properties;

[0065] The described pressure sizing roller 54 is located below the impregnating tank and is between the guide roller 52 and the sizing roller 55; it is used to increase the impregnation pressure to improve the penetration and impregnation of the thermoplastic resin into the continuous fibers and reduce the porosity of the prepreg wire.

[0066] Furthermore, the temperature measuring device 57 and the heat-insulating device 58 of the resin impregnation system are located at the bottom of the impregnating tank, which are used to keep the viscosity of the sizing solution in the resin impregnation system 5 constant to ensure the quality stability of the prepreg wire under different environments.

[0067] Furthermore, the solution volatilization system 6 includes a solution volatilization system inlet channel 61, a solution volatilization system heat-insulating device 62, a solution volatilization system temperature measuring device 63, a solution volatilization system temperature control device 64, a solution volatilization system outlet channel 65, and a nitrogen protection device 66;

[0068] Both the solution volatilization system inlet channel 61 and the solution volatilization system outlet channel 65 adopt rectangular channels, and their aspect ratio is 20:1 - 40:1, which is used to expand the specific surface area of the composite strip to improve the solvent volatilization effect and efficiency to increase the interfacial bonding strength between the continuous fibers and the thermoplastic resin and the continuous production efficiency;

[0069] The described nitrogen protection device 66 includes a nitrogen storage device, a nitrogen supply valve, and a nitrogen discharge valve, which are used to prevent problems such as thermoplastic resin degradation and steam corrosion of the device during the solvent volatilization process.

[0070] Further, the shaping system 7 includes a first-level temperature control device 71, a second-level temperature control device 72, a third-level temperature control device 73, a first-level shaping die 74, a second-level shaping die 75, a third-level shaping die 76, a first-level temperature measuring device 77, a second-level temperature measuring device 78, and a third-level temperature measuring device 79;

[0071] The first-level shaping die 74, the second-level shaping die 75, and the third-level shaping die 76 are arranged in sequence from the continuous fiber inlet side to the continuous fiber outlet side of the shaping system;

[0072] The first-level temperature control device 71 and the first-level temperature measuring device 77 are respectively arranged on the upper and lower parts of the first-level shaping die 74; similarly, the second-level temperature control device 72 and the second-level temperature measuring device 78 are respectively arranged on the upper and lower parts of the second-level shaping die 75; the third-level temperature control device 73 and the third-level temperature measuring device 79 are respectively arranged on the upper and lower parts of the third-level shaping die 76.

[0073] Further, the part of the first-level shaping die 74 in contact with the cross-section of the prepreg tape uses a rectangular channel with an aspect ratio of 15:1 - 30:1, and the other end of the channel uses an oval channel with an aspect ratio of 8:1 - 20:1;

[0074] The part of the second-level shaping die 75 in contact with the cross-section of the prepreg wire uses an oval channel with an aspect ratio of 4:1 - 10:1, and the other end of the channel uses an oval channel with an aspect ratio of 2:1 - 4:1;

[0075] The part of the third-level shaping die 76 in contact with the cross-section of the prepreg wire uses a circular channel with a diameter of 0.40 - 0.90 mm, and the other end uses a circular channel with a diameter of 0.30 - 0.80 mm.

[0076] As Figure 1 shown in the overall schematic diagram of the device of the present invention, the process of preparing the 3D printing continuous fiber reinforced thermoplastic resin composite prepreg wire based on solution impregnation specifically includes the following steps:

[0077] Step 1, the continuous filament bundle is drawn from the wire feeding unit 1 and the tension unit 2 to the fiber pretreatment system at a constant rate and tension, and the fiber is processed by the fiber spreading unit 3 and the preheating unit 4 to obtain an activated continuous fiber bundle with improved properties; as Figure 2 is the cross-sectional view of the fiber spreading unit and Figure 3 is the cross-sectional view of the preheating unit shown;

[0078] Step 2: Add the resin in solution state to the resin impregnation system 5, and convey the above-mentioned continuous fiber tow to the resin impregnation system 5, so that the thermoplastic resin dispersed in the solvent completely wraps around the outside of the fiber. Through the extrusion of the pressure rubber roller 54, the thermoplastic resin dipping solution fully penetrates into the continuous tow to eliminate the pores inside the prepreg wire and obtain the prepreg tape; as Figure 4 shown in the cross-sectional view of the resin impregnation system;

[0079] Step 3: Introduce the prepreg tape into the solution volatilization device 6 through the channel 61 of the solution volatilization system. The solution volatilization temperature needs to be higher than the boiling point of the solvent to ensure that the solution is completely volatilized to guarantee the bonding strength between the fiber and the thermoplastic resin, thereby enhancing the mechanical strength of the prepreg wire; as Figure 5 shown in the cross-sectional view of the solution volatilization system;

[0080] Step 4: Pull the prepreg tape to the shaping device 7, and pass through a multi-stage shaping die higher than the melting point of the thermoplastic resin to realize the transformation from the prepreg tape to a prepreg wire with high roundness, low porosity and uniform fiber distribution; as Figure 6 shown in the cross-sectional view of the wire shaping system;

[0081] Step 5: Cool and wind up the continuous fiber reinforced thermoplastic resin prepreg wire through the post-treatment system via the cooling device 8 and the winding device 9.

[0082] The content not described in detail in the specification of the present invention belongs to the prior art well-known to those skilled in the art. Although the illustrative specific embodiments of the present invention are described above to facilitate the understanding of the present invention by those skilled in the art, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention defined and determined by the appended claims, these changes are obvious, and all inventions and creations using the concept of the present invention are within the scope of protection.

Claims

1. An apparatus for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire, characterized in that: The device includes: A continuous wire feeding system, placed at the very front of the entire device, including a wire feeding unit (1) and a tension unit (2), for continuously feeding the fiber tow at a constant speed and tension; A fiber pretreatment system, located behind the continuous wire feeding system, including a fiber spreading unit (3) and a preheating unit (4), for activating the physical and chemical properties of continuous fibers; A resin impregnation system (5), located behind the fiber pretreatment system, for impregnating continuous fibers with a thermoplastic resin sizing solution; A solution volatilization system (6), located behind the resin impregnation system (5), for volatilizing the solution of continuous fibers containing the thermoplastic resin solution; A shaping system (7), located behind the solution volatilization system (6), for fixing the roundness shape of the composite prepreg wire and optimizing the fiber distribution; A post-treatment system, located behind the shaping system (7), including a cooling unit (8) and a winding unit (9), for performing subsequent treatment and winding of the shaped prepreg wire.

2. The device for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire according to claim 1, wherein: The wire feeding unit (1) is a constant-speed wire feeder and is connected to a wire feeding shaft to ensure that continuous fibers are impregnated with resin, have their solution volatilized, and are shaped into wire at a continuous and stable speed.

3. The device for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire according to claim 1, wherein: The tension unit (2) includes a tension sensor and a tension controller, both of which are controlled and driven by a PLC circuit and a servo motor.

4. The device for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire according to claim 1, wherein: The fiber spreading unit (3) includes a positioning guide roller (31), a fiber spreading unit outlet channel (32), a vacuum generator (33), and an air duct (34); the continuous fibers passing through the positioning guide roller (31) are dispersed perpendicular to the air flow direction in the air flow generated by the vacuum generator (33) through the air duct (34), achieving smooth and uniform broadening of the fiber tow to enhance the penetration characteristics of the thermoplastic resin into the continuous fibers; the fiber spreading unit outlet channel (32) is a rectangular channel with an aspect ratio of 30:1 to 50:1 to maintain the spreading width of the continuous fibers and reduce the porosity of the subsequent prepreg wire.

5. The device for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire according to claim 1, characterized in that: The preheating unit (4) includes a preheating unit inlet channel (41), a preheating unit heat preservation device (42), a preheating unit temperature measuring device (43), a preheating unit temperature control device (44), and a preheating unit outlet channel (45); both the preheating unit inlet channel (41) and the preheating unit outlet channel (45) are rectangular channels with an aspect ratio of 30:1 - 50:1 to prevent the continuous fibers spread to the specified width from affecting the product quality of the subsequent prepreg wire after retraction.

6. The device for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire according to claim 1, characterized in that: The resin impregnation system (5) is an impregnation tank, specifically including a resin impregnation system inlet channel (51), a guide roller (52), a sealed heat preservation tank (53), a pressure rubber roller (54), a scraping rubber roller (55), a resin impregnation system outlet channel (56), a resin impregnation system temperature measuring device (57), and a resin impregnation system heat preservation device (58); The described sealed heat-insulating tank (53) is used to reduce the adverse effects caused by the increase in the viscosity of the impregnating solution due to solvent volatilization; both the resin impregnation system inlet channel (51) and the resin impregnation system outlet channel (56) adopt rectangular channels; the aspect ratio of the resin impregnation system inlet channel (51) is 30:1 to 50:1, which is used to increase the impregnation area of the continuous filament bundle to reduce the porosity of the prepreg; the aspect ratio of the resin impregnation system outlet channel (56) is 20:1 - 40:1, which is used to expand the volatilization area of the prepreg strip, improve the volatilization effect and efficiency of the solvent in the prepreg strip to reduce the probability of thermoplastic resin degradation and ensure the performance of the prepreg wire; The described guide roller (52) is located above the impregnating tank and is arranged on the side close to the resin impregnation system inlet channel (51); it ensures that the continuous fiber passing through the resin impregnation system inlet channel (51) enters the predetermined impregnation position to ensure the uniform stability of the mechanical properties of the prepreg wire; The described sizing roller (55) is located above the impregnating tank, parallel to the guide roller (52), and is arranged on the side close to the resin impregnation system outlet channel (56); It is used to remove the excess sizing agent in the fiber bundle to increase the volume content of the continuous fiber in the prepreg wire and the uniformity of the mechanical properties; The described pressure sizing roller (54) is located below the impregnating tank and is between the guide roller (52) and the sizing roller (55); it is used to increase the impregnation pressure to enhance the penetration and impregnation of the thermoplastic resin into the continuous fiber and reduce the porosity of the prepreg wire.

7. An apparatus for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire according to claim 6, characterized in that: The described resin impregnation system temperature measuring device (57) and resin impregnation system heat insulation device (58) are located at the bottom of the impregnating tank, which is used to keep the viscosity of the impregnating solution in the resin impregnation system (5) constant to ensure the quality stability of the prepreg wire under different environments.

8. The device for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire according to claim 1, wherein: The described solution volatilization system (6) includes a solution volatilization system inlet channel (61), a solution volatilization system heat insulation device (62), a solution volatilization system temperature measuring device (63), a solution volatilization system temperature control device (64), a solution volatilization system outlet channel (65), and a nitrogen protection device (66); Both the solution volatilization system inlet channel (61) and the solution volatilization system outlet channel (65) adopt rectangular channels, and their aspect ratio is 20:1 - 40:1, which is used to expand the specific surface area of the composite strip to improve the solvent volatilization effect and efficiency to increase the interfacial bonding strength between the continuous fiber and the thermoplastic resin and the continuous production efficiency; The described nitrogen protection device (66) includes a nitrogen storage device, a nitrogen supply valve, and a nitrogen discharge valve, which is used to prevent problems such as thermoplastic resin degradation and steam corrosion of the device during the solvent volatilization process.

9. The device for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire according to claim 1, wherein: The described shaping system (7) includes a first-stage temperature control device (71), a second-stage temperature control device (72), a third-stage temperature control device (73), a first-stage shaping die (74), a second-stage shaping die (75), a third-stage shaping die (76), a first-stage temperature measuring device (77), a second-stage temperature measuring device (78), and a third-stage temperature measuring device (79); The described Class-I shaping die (74), Class-II shaping die (75) and Class-III shaping die (76) are arranged in sequence from the continuous fiber inlet side to the continuous fiber outlet side of the shaping system; The described Class-I temperature control device (71) and Class-I temperature measuring device (77) are respectively arranged at the upper and lower parts of the Class-I shaping die (74); similarly, the Class-II temperature control device (72) and Class-II temperature measuring device (78) are respectively arranged at the upper and lower parts of the Class-II shaping die (75); the Class-III temperature control device (73) and Class-III temperature measuring device (79) are respectively arranged at the upper and lower parts of the Class-III shaping die (76); the part of the Class-I shaping die (74) in contact with the cross-section of the prepreg strip uses a rectangular channel, and the aspect ratio of its length to width is 15:1 - 30:1, and the other end of the channel uses an oval channel, and the aspect ratio of its length to width is 8:1 - 20:1; The part of the described Class-II shaping die (75) in contact with the cross-section of the prepreg wire uses an oval channel, and the aspect ratio of its length to width is 4:1 - 10:1, and the other end of the channel uses an oval channel, and the aspect ratio of its length to width is 2:1 - 4:1; The part of the described Class-III shaping die (76) in contact with the cross-section of the prepreg wire uses a circular channel with a diameter of 0.40 - 0.90 mm, and the other end uses a circular channel with a diameter of 0.30 - 0.80 mm.

10. A method for preparing a continuous fiber reinforced thermoplastic resin composite prepreg wire based on the device according to any one of claims 1 to 9, characterized in that: It includes the following steps: Step 1, lead the continuous tow out from the wire feeding unit (1) and the tension unit (2) to the fiber pretreatment system at a constant rate and tension, and process the fiber through the fiber spreading unit (3) and the preheating unit (4) to obtain a continuous fiber bundle with activated performance; Step 2, add the resin in a solution state to the resin impregnation system (5), convey the above continuous fiber tow to the resin impregnation system (5), make the thermoplastic resin dispersed in the solvent completely wrap the outside of the fiber, and make the thermoplastic resin impregnating solution fully penetrate and impregnate into the continuous tow through the extrusion of the rubber pressing roller (54) to eliminate the pores inside the prepreg wire and obtain the prepreg strip; Step 3, introduce the prepreg strip into the solution volatilization device (6) through the channel (61) of the solution volatilization system. The solution volatilization temperature needs to be higher than the boiling point of the solvent to ensure that the solution is completely volatilized to ensure the bonding strength between the fiber and the thermoplastic resin, thereby improving the mechanical strength of the prepreg wire; Step 4, tow the prepreg strip to the shaping device (7), and pass through multi-stage shaping dies with a temperature higher than the melting point of the thermoplastic resin to realize the transformation from the prepreg strip to a prepreg wire with high roundness, low porosity and uniform fiber distribution; Step 5, perform cooling and winding treatments on the continuous fiber reinforced thermoplastic resin prepreg wire through the post-treatment system via the cooling device (8) and the winding device (9).

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