Continuous fiber 3D printing composite filament forming device and processing method

Abstract

The invention discloses a continuous fiber 3D printing composite filament forming device and a processing method, and relates to the technical field of continuous fiber reinforced resin materials. Comprising a machine body, a controller, an extrusion device, a continuous carbon fiber outlet roller, a composite die and a composite filament winding roller, the composite die comprises a first cavity, a second cavity, a first sprue spreader and a second sprue spreader, and the first sprue spreader and the second sprue spreader are each in a semi-cone shape and are each provided with a semi-fiber guide hole; and a fiber bundle inlet is formed after the sprue spreader I and the sprue spreader II are oppositely combined. By means of the folding structure, threading is convenient and fast, and the machining efficiency is greatly improved. The measures of segmented temperature control, pressure control of the working cavity (infiltration cavity) and walking speed and tension control are utilized, so that the yield of finished silk is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of continuous fiber reinforced resin materials technology, and in particular to improvements and processing methods for continuous fiber 3D printing composite filament forming devices. Background Technology

[0002] Currently, in fields such as aerospace, automotive, robotics, medical, and high-end equipment, where lightweighting, high specific strength, high specific modulus, and integrated structural molding are required, continuous carbon fiber reinforced 3D printing composite filaments are beginning to be used as structural-level 3D printing materials. These composite filaments are thermoplastic resin-based materials with carbon fiber as the reinforcing phase, manufactured through impregnation or co-extrusion processes, and are capable of melt deposition modeling.

[0003] Due to the low surface energy and poor wettability of carbon fiber, the processing of continuous, large-tow carbon fiber filaments with resin is difficult, resulting in a low yield. The main technical challenges in the processing of composite fibers are as follows: First, the initial guidance of continuous carbon fiber bundles is difficult. Traditional processes require the use of guide ropes for connection and then threading them through small holes in the mold. However, the mold has fiber spreading protrusions inside, making it difficult for the guide ropes to pass through smoothly, which makes the operation difficult. Secondly, the pressure on the continuous fiber bundles along the bundle direction in the impregnation tank is uneven and insufficient, which makes the finished composite yarn prone to severe fiber bundle eccentricity or even exposure.

[0004] Therefore, how to maximize the quality of composite yarns without using sizing agents (improper use can lead to interfacial blockage) and improve processing efficiency through equipment improvements has become a pressing technical problem in this field. Summary of the Invention

[0005] To address the above-mentioned technical problems, this invention provides a continuous fiber 3D printing composite filament forming device and processing method that is user-friendly, minimizes fiber bundle eccentricity, and improves the uniformity and density of the finished composite filament.

[0006] The technical solution of this invention is a continuous fiber 3D printing composite filament forming device, comprising a machine body, a controller, an extrusion device, a continuous carbon fiber output roller, a composite mold, and a composite filament winding roller. The composite mold includes a cavity one, a cavity, a flow divider cone one, and a flow divider cone two. Both the first and second diversion cones are semi-conical in shape and are provided with semi-fiber guide holes, so that the first and second diversion cones have fiber bundle inlets after they are joined together; The cavity is disposed on the machine body. The cavity has a working surface. The working surface is provided with a concave semi-conical surface for accommodating the flow divider cone, an impregnation cavity, a semi-conical diameter reduction cavity, and a semi-circular filament exit cavity. The concave semi-conical surface is provided with a resin inlet for connecting to the extrusion device. The taper of the flow divider cone is smaller than that of the concave semi-conical surface, so that a wedge cavity is formed between the flow divider cone and the concave semi-conical surface of the cavity. The port of the wedge cavity has an annular gap. The second cavity is detachably connected to the first cavity. The second cavity has a second working surface. The second working surface is sequentially provided with a second concave semi-conical surface for accommodating the second flow divider cone, a second wetting cavity, a second semi-conical diameter reduction cavity, and a second semi-circular wire exit cavity. The taper of the second flow divider cone is smaller than that of the second concave semi-conical surface, so that a second wedge cavity is formed between the second flow divider cone and the second concave semi-conical surface of the second cavity. The port of the second wedge cavity has an annular gap. After cavity two is connected to cavity one, wedge cavity one and wedge cavity two are joined together to form a complete wedge cavity, and annular gap one and annular gap two are joined together to form an annular gap; the tail end of the semi-circular filament outlet cavity one and semi-circular filament outlet cavity two after being joined together is the composite filament outlet.

[0007] Furthermore, a fiber spreading protrusion 1 is provided in the first impregnation chamber, and a fiber spreading protrusion 2 is provided in the second impregnation chamber. The axial positions of the fiber spreading protrusion 1 and the fiber spreading protrusion 2 are staggered, so that the axially running carbon fiber is wavy.

[0008] Furthermore, a pressure sensor mounting hole is provided on the first cavity, which is connected to the first immersion cavity. A pressure sensor is connected in the pressure sensor mounting hole, and the pressure sensor is connected to the controller.

[0009] Furthermore, at least two heating rod mounting holes 1 are provided in sections on the first cavity, and at least two heating rod mounting holes 2 are provided in sections on the second cavity. Heating rods are respectively installed in the first heating rod mounting holes and the second heating rod mounting holes, and the heating rods are connected to the controller.

[0010] Furthermore, at least two temperature sensors are provided in sections on cavity one and / or cavity two, and the temperature sensors are connected to the controller.

[0011] Furthermore, a connector is provided at the bottom of the cavity.

[0012] Furthermore, a cone sleeve adapted to the flow cone one and the flow splitting cone two is provided in the inclined wedge cavity, and the length of the cone sleeve is less than the depth of the resin inlet.

[0013] Furthermore, heat-insulating structures are provided in the rear portions of both cavity one and cavity two.

[0014] Furthermore, a cooling device is provided outside the composite filament outlet.

[0015] The method for processing continuous fiber 3D printing composite filaments using the molding apparatus of the present invention is carried out according to the following steps. S1, split cavity Disassemble cavity two from cavity one, so that the working surface of cavity one, together with the semi-fiber guide hole of flow divider cone one, is in an open state. S2, Place continuous carbon fiber. Take the head of the carbon fiber bundle from the continuous carbon fiber output roller, stretch it, and place it into the semi-fiber guide hole, the impregnation cavity, the semi-conical diameter reduction cavity, and the semi-circular output cavity on the working surface of the split cone I in the open state, and then connect it to the composite filament winding roller. S3. Preheating of carbon fiber bundles The heating rod (81) is controlled to heat the flow divider cone and the cavity as a whole, so that the carbon fiber bundle at the flow divider cone position is preheated; S4, molten resin, The resin is heated and melted until it meets the processing requirements, then kept at that temperature and set aside for later use. S5, resin injection, segmented temperature control. The resin is injected into the inclined wedge cavity (506) through the resin inlet (512), and then enters the impregnation cavity section (502), the diameter reduction section (503) and the shaping section (504) in sequence through the annular gap (507) until the composite yarn outlet (505). At this time, the carbon fiber bundle is stationary. After the resin flows to the composite filament outlet (505), the heating rod (81) is controlled to perform segmented temperature control. S6, composite filament forming The composite filament winding roller (6) drives the head of the carbon fiber bundle with tension F1 to wind the filament, and the controller (2) controls the tension of the continuous carbon fiber output roller (4) to be F2 to ensure that the carbon fiber bundle is in a taut state during operation.

[0016] From a structural perspective, the present invention firstly improves the composite mold into a mating structure, which greatly improves the threading efficiency during threading and eliminates the need for the traditional method of pulling the guide wire.

[0017] Secondly, a wedge cavity is designed between the flow divider cone and the cavity, which causes the molten resin to form a Venturi effect when it flows to the annular gap at the top of the wedge cavity, creating a "spraying" effect on the fiber bundle and individual fibers, resulting in more comprehensive contact between the fibers and the resin.

[0018] Third, a two-stage diameter reduction section (diameter reduction section and shaping section) is set at the rear of the cavity. Combined with temperature-controlled curing, the widened fiber bundles are then gathered back and cured at a position closer to the axis. Ultimately, this makes the fiber-resin composite more compact and the fiber position accuracy higher.

[0019] From a technological perspective, the mating structure of this invention facilitates yarn threading and significantly improves processing efficiency. By utilizing segmented temperature control, working chamber (immersion chamber) pressure control, and measures for controlling travel speed and tension, the yield of finished yarns is greatly enhanced. Attached Figure Description

[0020] Figure 1 This is a three-dimensional schematic diagram of the molding device of the present invention. Figure 1 , Figure 2 This is a three-dimensional schematic diagram of the molding device of the present invention. Figure 2 , Figure 3 This is a three-dimensional schematic diagram of the molding die in the molding device of the present invention. Figure 4 This is an exploded three-dimensional view of the molding die in the molding device of the present invention. Figure 5 This is a perspective view of the cavity and the flow divider cone in the molding die of the present invention. Figure 6 This is a schematic diagram of the cavity and flow divider cone in the molding die of the present invention. Figure 7 yes Figure 6 Left view, Figure 8 yes Figure 6 Sectional view AA Figure 9 yes Figure 8 Enlarged view of part B in the middle. Figure 10 This is a schematic diagram of the processing procedure of the present invention. Figure 11 This is a schematic diagram of another embodiment of the cavity and flow divider cone in the molding die of the present invention. Figure 12 This is a three-dimensional representation of the flow divider cone assembly state in the molding die of the present invention. Figure 1 , Figure 13 This is a three-dimensional representation of the flow divider cone assembly state in the molding die of the present invention. Figure 2 , Figure 14 This is a three-dimensional schematic diagram of the cavity in the molding die of the present invention. Figure 15 This is a cross-sectional schematic diagram of the finished composite filament processed by this invention. Figure 16 This is a schematic diagram of the processing principle of the present invention; In the diagram: 1 is the machine body, 2 is the controller, 3 is the extrusion device, 4 is the continuous carbon fiber output roller, 5 is the composite mold, 51 is cavity one, 510 is impregnation cavity one, 5101 is fiber spreading protrusion one, 511 is heating rod mounting hole one, 512 is the resin inlet, 513 is the pressure sensor mounting hole, 514 is the heat-insulating structure, 52 is cavity two, 520 is impregnation cavity two, 5201 is fiber spreading protrusion two, 521 is heating rod mounting hole two, 53 is the flow divider cone one, and 54 is the flow divider cone one. Flow cone two, 55 is the connector, 500 is the fiber bundle inlet, 501 is the fiber bundle preheating section, 5010 is the fiber bundle outlet, 502 is the impregnation chamber section, 503 is the diameter reduction section, 504 is the shaping section, 505 is the composite filament outlet, 506 is the wedge cavity, 507 is the annular gap, 508 is the cone sleeve, 6 is the composite filament winding roller, 61 is the cooling device, 7 is the pressure sensor, 81 is the heating rod, 82 is the temperature sensor, 9 is the composite filament, 91 is the carbon fiber, and 92 is the resin; Figure 16 In the diagram, hollow arrows indicate the direction of carbon fiber movement, dashed arrows indicate the direction of resin injection, and curved arrows indicate the direction of rotation of the composite filament winding roller. F1 represents the tension of the composite filament winding roller, and F2 represents the tension of the continuous carbon fiber output roller. The dashed lines I, II, III, IV, V, and VI represent different temperature control zones. Detailed Implementation

[0021] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0022] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual images. They should not be construed as limiting the scope of this patent. To better illustrate the embodiments of the present invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0023] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0024] In the description of this invention, unless otherwise explicitly specified and limited, the term "connection" or similar designation indicating a connection between components should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] A continuous fiber 3D printing composite filament forming device, such as Figure 1-7 As shown, it includes a machine body 1, a controller 2, an extrusion device 3, a continuous carbon fiber output roller 4, a composite mold 5, and a composite filament winding roller 6. The composite mold 5 includes cavity 1 51, cavity 52, flow divider cone 1 53, and flow divider cone 2 54. Both the first diversion cone 53 and the second diversion cone 54 are semi-conical in shape. In this invention, they specifically refer to semi-conical bodies split along the axis, and each is provided with a semi-fiber guide hole, so that the first diversion cone 53 and the second diversion cone 54 have a fiber bundle inlet 500 after being joined together. Cavity 51 is set on the machine body 1 and can also be directly connected to the discharge port of the extrusion device 3. Cavity 51 has a working surface. On the working surface, a concave semi-conical surface for accommodating the diverting cone 53, an impregnation chamber 510, a semi-conical diameter reduction chamber, and a semi-circular filament discharge chamber are sequentially provided. A resin inlet 512 for connecting the extrusion device 3 is provided on the concave semi-conical surface. The taper of the diverting cone 53 is smaller than that of the concave semi-conical surface, so that a wedge cavity is formed between the diverting cone 53 and the concave semi-conical surface of the cavity 51. An annular gap is left at the port of the wedge cavity. Cavity 2 52 is detachably connected to cavity 1 51. Cavity 2 52 has working surface 2. On working surface 2, there are sequentially formed a concave semi-conical surface 2 for accommodating flow divider cone 2 54, an impregnation cavity 2 520, a semi-conical diameter reduction cavity 2, and a semi-circular wire exit cavity 2. The taper of flow divider cone 2 54 is smaller than that of concave semi-conical surface 2, so that a wedge cavity 2 is formed between flow divider cone 2 54 and concave semi-conical surface 2 of cavity 2 52. An annular gap 2 is left at the port of wedge cavity 2. After cavity 2 52 is connected to cavity 1 51, oblique wedge cavity 1 and oblique wedge cavity 2 are combined to form a complete oblique wedge cavity 506, and annular gap 1 and annular gap 2 are combined to form annular gap 507. The structure of annular gap 507 has a Venturi effect, which allows the molten liquid resin to form an "acceleration" effect after passing through annular gap 507. The tail end after the semi-circular filament outlet cavity 1 and semi-circular filament outlet cavity 2 are combined is the composite filament outlet 505. At the same time, the design of the flow divider cone can also conduct heat to the carbon fiber filaments passing through it, ensuring that the carbon fiber filaments enter the resin in a heated state.

[0026] Impregnation chamber 1 510 and impregnation chamber 2 520 are paired to form impregnation chamber section 502, semi-conical diameter reduction chamber 1 and semi-conical diameter reduction chamber 2 are paired to form diameter reduction section 503, and semi-circular yarn exit chamber 1 and semi-circular yarn exit chamber 2 are paired to form shaping section 504; the tail end of shaping section 504 is composite yarn exit 505.

[0027] Furthermore, such as Figure 9 , 10 As shown, a fiber spreading protrusion 5101 is provided in impregnation chamber 1 510, and a fiber spreading protrusion 5201 is provided in impregnation chamber 2 520. The axial positions of the fiber spreading protrusion 1 5101 and the fiber spreading protrusion 2 5201 are staggered, making the axially running carbon fibers wavy. The wavy protrusion structure allows the carbon fiber bundle to fully spread out, increasing the contact area with the resin and providing the resin with more "attachment points" and "penetration" paths. This allows the resin to impregnate the fibers more fully and evenly, reducing defects such as dry spots and pores. Combined with the control of tension at both ends, the distribution of resin 92 and carbon fiber 91 in the composite filament 9 is closer to an ideal state, such as... Figure 15 As shown.

[0028] Furthermore, such as Figure 3 , 4 As shown, a pressure sensor mounting hole 513 is also provided on the cavity 51, which is connected to the impregnation cavity 510. A pressure sensor 7 is connected inside the pressure sensor mounting hole 513, and the pressure sensor 7 is connected to the controller 2. The bonding pressure, impregnation pressure, or molding pressure between the carbon fiber and the resin is detected in real time to avoid excessive resin extrusion due to excessive pressure, or insufficient impregnation and internal pores due to insufficient pressure, thereby stabilizing the molding quality and structural performance of the composite yarn 9.

[0029] Furthermore, at least two heating rod mounting holes 511 are provided in sections on cavity 1 51, and at least two heating rod mounting holes 521 are provided in sections on cavity 2 52. Heating rods 81 are respectively provided in heating rod mounting holes 511 and heating rod mounting holes 521, and heating rods 81 are connected to controller 2.

[0030] Furthermore, at least two temperature sensors 82 are provided in sections on cavity one 51 and / or cavity two 52, and the temperature sensors 82 are connected to the controller 2.

[0031] like Figure 3-4As shown in Figure 16, this invention features multiple heating zones at different temperatures, enabling staged control of heating temperature and rate according to the different stages of resin melting, impregnation, and curing. This avoids problems such as resin overheating and decomposition, premature curing, or insufficient fluidity caused by a single heating cycle. Segmented temperature control ensures sufficient impregnation and tight bonding between the resin and carbon fiber, while reducing defects such as bubbles, pores, localized scorching, or incomplete curing, significantly improving the molding quality, structural stability, and production efficiency of the composite filament 9.

[0032] Furthermore, a connector 55 is provided at the bottom of cavity 51. It can be fixed or movable, such as a hinge, to facilitate the support and connection of cavity 52 when disassembling cavity 52.

[0033] Furthermore, such as Figure 8 As shown, a conical sleeve 508 adapted to the first and second flow-dividing cones 53 and 54 is provided in the wedge cavity 506. The length of the conical sleeve 508 is less than the depth of the resin inlet 512. This effectively prevents the resin melt from forming a dead zone on the left side of the resin inlet 512, blocking the resin inlet 512 and interfering with the flow path of the resin melt. Adding the conical sleeve 508 can effectively ensure the smooth flow of the resin melt from the resin inlet 512 into the wedge cavity 506.

[0034] Furthermore, such as Figure 11 As shown, heat-insulating structures 514 are respectively provided in the rear parts of cavity one 51 and cavity two 52. This reduces heat conduction from the front to the rear, resulting in better resin curing in the diameter reduction section 503 to the shaping section 504, thereby reducing the eccentricity.

[0035] Furthermore, such as Figure 16 As shown, a cooling device 61 is also provided outside the composite filament outlet 505. This device rapidly and uniformly cools and shapes the resin-impregnated carbon fiber composite material, allowing the resin to transition from a molten state to a solidified and stable state in a short time. This prevents the resin from flowing, deforming, or over-curing due to high temperatures, ensuring a uniform resin layer thickness and a smooth surface. At the same time, it improves the molding efficiency and dimensional stability of the composite filament 9, prevents adhesion, misalignment, or structural defects in subsequent processes, and enhances the overall product quality.

[0036] like Figure 16 As shown, the method for processing continuous fiber 3D printing composite filaments using the molding device of the present invention is carried out according to the following steps: S1, split cavity Disassemble cavity 2 52 from cavity 1 51, so that the working surface of cavity 1 51 and the semi-fiber guide hole of the flow divider cone 1 53 are in an open state. S2, Place continuous carbon fiber. Take the head of the carbon fiber bundle from the continuous carbon fiber output roller 4, stretch it, and place it into the semi-fiber guide hole, the impregnation cavity 510, the semi-conical diameter reduction cavity and the semi-circular output cavity on the working surface of the split cone 53 which is in an open state, and then connect it to the composite filament winding roller 6. S3. Preheating of carbon fiber bundles The heating rod (81) is controlled to heat the flow divider cone and the cavity as a whole, so that the carbon fiber bundle at the flow divider cone position is preheated; S4, molten resin, The resin is heated and melted until it meets the processing requirements, then kept at that temperature and set aside for later use. S5, resin injection, segmented temperature control. The resin is injected into the inclined wedge cavity (506) through the resin inlet (512), and then enters the impregnation cavity section (502), the diameter reduction section (503) and the shaping section (504) in sequence through the annular gap (507) until the composite yarn outlet (505). At this point, the carbon fiber bundle is stationary. After the resin flows to the composite filament outlet (505), the heating rod (81) is controlled for segmented temperature control. The resin fills the space inside the cavity, fully removes the gas, and then performs segmented temperature control to create a difference in the viscosity index of the resin in the axial direction. This facilitates the initial wetting and subsequent shaping.

[0037] This invention uses six temperature control zones as an example. Carbon fiber 91 enters the fiber bundle inlet 500 of the splitter cone, then proceeds to the fiber bundle preheating section 501, and finally exits at the fiber bundle outlet 5010. This is temperature control zone I, where the carbon fiber 91 undergoes initial preheating within the mold cavity. The splitter cone and the resin within it are also heated. The splitter cone conducts heat through the carbon fiber filaments, ensuring they enter the resin in a heated state. The preheating time of the fiber bundle is controlled by adjusting the fiber feed speed. The purpose is to reduce the temperature difference between the fiber bundle and the resin. When the high-temperature resin encounters the cold fiber bundle, a film quickly forms on the resin surface, and the resulting resin loses its viscous properties. Meanwhile, the carbon fiber surface is heated and in a molten state. Entering the hot resin, it can effectively mix, producing a cross-phase and resulting in a tighter bond.

[0038] The impregnation chamber 502 is divided into temperature control zone II and temperature control zone III. To ensure the impregnation effect, segmented temperature control can be adopted. Temperature control zone II ensures that the resin 92 is in a molten state, ensuring that the resin 92 flows smoothly and fully impregnates each carbon fiber 91 in the fiber bundle. Temperature control zone III is slightly lower than the temperature of the front zone to reduce the viscosity of the resin 92. At this time, the pressure value in this area needs to be monitored in real time by the pressure sensor 7. If it exceeds the design threshold, the controller 2 adjusts the temperature of temperature control zone III to maintain the flow properties of the resin 92.

[0039] Temperature control zone IV, where the temperature is further lower than that of temperature control zone III, and the shape inside the cavity is conical, that is, the shaping and diameter reduction begin. The purpose is to initially cool down the composite filament 9 after high-temperature impregnation, so that the resin 92 is initially shaped and prevents the resin 92 from deforming, which would cause the carbon fiber 91 to become eccentric.

[0040] The tail section is temperature control zone V, where the temperature is further reduced to allow the resin to transition from a molten state to a cured state, ensuring uniform resin layer thickness and structural stability, with the carbon fiber positioned in the middle.

[0041] Cooling device 61 is temperature control zone VI, located outside the cavity, which deeply cools the composite filament 9, so that the resin is completely cured and shaped, improving the dimensional accuracy and structural strength of the composite material, and meeting the requirements of subsequent winding, cutting and other processes.

[0042] To avoid poor temperature control reliability due to the thermal conduction effect of the cavity metal material, the present invention also proposes to set a heat-insulating structure 514 between several temperature control areas at the tail.

[0043] Furthermore, the temperature control measures in this invention are dynamic controls, i.e., the preheating process, which differs from the control strategy of the actual molding process. The preheating process requires the resin to be poured into the cavity space to completely cover the static fiber bundles; then molding is carried out, and during molding, segmented temperature control is required according to the aforementioned temperature control measurements.

[0044] S6, composite filament forming The composite filament winding roller (6) drives the head of the carbon fiber bundle with tension F1 to wind the filament, and the controller (2) controls the tension of the continuous carbon fiber output roller (4) to be F2 to ensure that the carbon fiber bundle is in a taut state during operation.

[0045] It should be stated that the above-described specific embodiments are merely preferred embodiments of the present invention and the technical principles employed. Those skilled in the art should understand that various modifications, equivalent substitutions, and variations can be made to the present invention based on the technical content disclosed in this application. However, such variations, as long as they do not depart from the spirit of the present invention, should be within the protection scope of the present invention. Furthermore, some terminology used in this specification and claims is not limiting, but merely for ease of description.

Claims

1. A continuous fiber 3D printing composite filament forming device, comprising a machine body (1), a controller (2), an extrusion device (3), a continuous carbon fiber filament output roller (4), a composite mold (5), and a composite filament winding roller (6), characterized in that, The composite mold (5) includes cavity one (51), cavity (52), flow divider cone one (53) and flow divider cone two (54). Both the first diversion cone (53) and the second diversion cone (54) are semi-conical in shape and are respectively provided with semi-fiber guide holes, so that the first diversion cone (53) and the second diversion cone (54) have fiber bundle inlets (500) after they are joined together. The cavity 1 (51) is disposed on the machine body (1). The cavity 1 (51) has a working surface 1. The working surface 1 is provided with a concave semi-conical surface 1 for accommodating the flow divider cone 1 (53), an impregnation cavity 1 (510), a semi-conical diameter reduction cavity 1 and a semi-circular filament exit cavity 1 in sequence. The concave semi-conical surface 1 is provided with a resin inlet (512) for connecting the extrusion device (3). The taper of the flow divider cone 1 (53) is smaller than that of the concave semi-conical surface 1, so that a wedge cavity 1 is formed between the flow divider cone 1 (53) and the concave semi-conical surface 1 of the cavity 1 (51). The port of the wedge cavity 1 has an annular gap 1. The second cavity (52) is detachably connected to the first cavity (51). The second cavity (52) has a working surface, on which a concave semi-conical surface for accommodating the second diverter cone (54), an impregnation cavity (520), a semi-conical diameter reduction cavity, and a semi-circular wire exit cavity are sequentially provided. The taper of the second diverter cone (54) is smaller than that of the concave semi-conical surface, so that a wedge cavity is formed between the second diverter cone (54) and the concave semi-conical surface of the second cavity (52). The port of the wedge cavity has an annular gap. After cavity two (52) is connected to cavity one (51), the oblique wedge cavity one and oblique wedge cavity two are matched to form a complete oblique wedge cavity (506), and the annular gap one and annular gap two are matched to form an annular gap (507); the tail end of the semi-circular filament outlet cavity one and semi-circular filament outlet cavity two after being matched is the composite filament outlet (505).

2. The continuous fiber 3D printing composite filament forming device according to claim 1, characterized in that, A fiber spreading protrusion 1 (5101) is provided in the first impregnation chamber (510), and a fiber spreading protrusion 2 (5201) is provided in the second impregnation chamber (520). The axial positions of the fiber spreading protrusion 1 (5101) and the fiber spreading protrusion 2 (5201) are staggered, so that the axially running carbon fiber is wavy.

3. The continuous fiber 3D printing composite filament forming device according to claim 1, characterized in that, A pressure sensor mounting hole (513) is also provided on the cavity (51) to connect to the immersion cavity (510). A pressure sensor (7) is connected in the pressure sensor mounting hole (513), and the pressure sensor (7) is connected to the controller (2).

4. The continuous fiber 3D printing composite filament forming device according to claim 1, characterized in that, At least two heating rod mounting holes (511) are provided in sections on the first cavity (51), and at least two heating rod mounting holes (521) are provided in sections on the second cavity (52). Heating rods (81) are provided in the first heating rod mounting hole (511) and the second heating rod mounting hole (521), and the heating rods (81) are connected to the controller (2).

5. The continuous fiber 3D printing composite filament forming device according to claim 4, characterized in that, At least two temperature sensors (82) are also provided in sections on the first cavity (51) and / or the second cavity (52), and the temperature sensors (82) are connected to the controller (2).

6. The continuous fiber 3D printing composite filament forming device according to claim 1, characterized in that, A connector (55) is provided at the bottom of the cavity (51).

7. The continuous fiber 3D printing composite filament forming device according to claim 1, characterized in that, The inclined wedge cavity (506) is provided with a cone sleeve (508) adapted to the first flow splitter cone (53) and the second flow splitter cone (54), the length of the cone sleeve (508) being less than the depth of the resin inlet (512).

8. The continuous fiber 3D printing composite filament forming device according to claim 1, characterized in that, Heat-insulating structures (514) are provided in the rear parts of cavity one (51) and cavity two (52).

9. A continuous fiber 3D printing composite filament forming device according to claim 1, characterized in that, A cooling device (61) is also provided outside the composite filament outlet (505).

10. A method for processing continuous fiber 3D printing composite filaments using the molding apparatus of claim 1, comprising the following steps: S1, split cavity Disassemble cavity 2 (52) from cavity 1 (51) so that the working surface of cavity 1 (51) and the semi-fiber guide hole of the flow divider cone 1 (53) are in an open state. S2, Place continuous carbon fiber. Take the head of the carbon fiber bundle from the continuous carbon fiber output roller (4), stretch it, and place it into the semi-fiber guide hole, the impregnation cavity (510), the semi-conical diameter reduction cavity and the semi-circular output cavity on the working surface of the split cone (53) in the open state, and then connect it to the composite filament winding roller (6). S3. Preheating of carbon fiber bundles The heating rod (81) is controlled to heat the flow divider cone and the cavity as a whole, so that the carbon fiber bundle at the flow divider cone position is preheated; S4, molten resin, The resin is heated and melted until it meets the processing requirements, then kept at that temperature and set aside for later use. S5, resin injection, segmented temperature control. The resin is injected into the inclined wedge cavity (506) through the resin inlet (512), and then enters the impregnation cavity section (502), the diameter reduction section (503) and the shaping section (504) in sequence through the annular gap (507) until the composite yarn outlet (505). At this time, the carbon fiber bundle is stationary. After the resin flows to the composite filament outlet (505), the heating rod (81) is controlled to perform segmented temperature control. S6, composite filament forming The composite filament winding roller (6) drives the head of the carbon fiber bundle with tension F1 to wind the filament, and the controller (2) controls the tension of the continuous carbon fiber output roller (4) to be F2 to ensure that the carbon fiber bundle is in a taut state during operation.

Images