Fiber tow pretreatment system

Abstract

The invention relates to the technical field of composite material preparation, in particular to a fiber tow pretreatment system. The fiber tow pretreatment system comprises an impregnation tank and a treatment device, impregnation liquid is contained in the impregnation tank, the impregnation liquid comprises liquid and resin particles, the impregnation tank is used for impregnating fiber tows through the impregnation liquid, and the resin particles are attached to the fiber tows impregnated with the impregnation liquid; the processing device is arranged on the downstream side of the dipping tank in the advancing direction of the fiber tows, the processing device is used for drying liquid on the dipped fiber tows and can convert resin particles attached to the fiber tows into target resin particles, and the target resin particles are located between adjacent fiber filaments; and the adjacent fibers are spaced to form a flow guide channel. According to the design, when the fiber tows treated by the fiber tow pretreatment system are impregnated with resin, the resin can better enter the fiber tows through the flow guide channels, the infiltration effect is improved, and the quality of finished products is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of composite material preparation, and in particular to a fiber tow pretreatment system. Background Art

[0002] Prepregs are composites of a resin matrix and reinforcement, made by impregnating continuous fibers or fabrics with a resin matrix. High-performance composite materials made from prepregs are widely used in aerospace, industrial manufacturing, sports equipment, and other fields. However, during the prepreg preparation process, especially for heavyweight fabrics that require a large amount of fiber, there is a problem of insufficient resin impregnation of the fiber tows. This makes it difficult for the resin to penetrate the fiber tows, affecting the quality of the finished prepreg. Summary of the Invention

[0003] In order to overcome the problems existing in the related art, the present invention provides a fiber tow pretreatment system, which can improve the resin impregnation effect.

[0004] According to some embodiments, the present invention provides a fiber tow pretreatment system comprising: An impregnation tank containing an impregnation liquid, wherein the impregnation liquid includes liquid and resin particles, and the impregnation tank is used to impregnate fiber tows with the impregnation liquid, wherein the fiber tows impregnated with the impregnation liquid are attached with the resin particles; A processing device is arranged on the downstream side of the impregnation tank along the traveling direction of the fiber bundle. The processing device is used to dry the liquid on the impregnated fiber bundle and can convert the resin particles attached to the fiber bundle into target resin particles, and each of the target resin particles is located between adjacent fiber filaments so that adjacent fiber filaments are spaced apart to form a guide channel.

[0005] In some embodiments of the present invention, the boiling point of the liquid is lower than the melting point of the resin particles, the resin particles are thermoplastic resin particles, and the processing device includes: a drying furnace, wherein the heating temperature of the drying furnace is higher than the boiling point of the liquid, and is used to dry the liquid on the fiber tow; a melting furnace, disposed downstream of the drying furnace along the traveling direction of the fiber filaments, the melting furnace having a heating temperature lower than the melting point of the resin particles, for partially melting each of the resin particles to bond with the fiber filaments; A shaping furnace is provided on the downstream side of the melting furnace along the traveling direction of the fiber bundle, and the heating temperature of the shaping furnace is higher than the glass transition temperature of the resin particles, so as to transform each of the resin particles melted by the melting furnace into the target resin particles.

[0006] In some embodiments of the present invention, the shaping furnace comprises: a shaping furnace body, the shaping furnace body being used to gradually harden each of the resin particles melted by the melting furnace to a target state; A shaping assembly includes at least one set of pressing rollers, wherein the pressing rollers are used to press the resin particles in the target state so as to deform the resin particles in the target state into the target resin particles.

[0007] In some embodiments of the present invention, the fiber tow pretreatment system further comprises: At least one spreading roller is disposed in the impregnation tank and is used for spreading the fiber bundle so that the resin particles enter between adjacent fiber bundles.

[0008] In some embodiments of the present invention, the yarn spreading roller includes a main body and a plurality of arc-shaped protrusions and a plurality of arc-shaped grooves arranged on the outer peripheral surface of the main body, the plurality of arc-shaped protrusions are distributed in sequence along the axial direction of the main body, and each of the arc-shaped grooves is respectively located between adjacent arc-shaped protrusions, and adjacent arc-shaped protrusions and arc-shaped grooves are smoothly connected, wherein each of the arc-shaped protrusions and each of the arc-shaped grooves extend along the circumference of the main body so as to be arranged around the main body.

[0009] In some embodiments of the present invention, the at least one yarn spreading roller includes a first yarn spreading roller, a second yarn spreading roller and a third yarn spreading roller, and the first yarn spreading roller, the second yarn spreading roller and the third yarn spreading roller are arranged in sequence along the traveling direction of the fiber bundle, and along the traveling direction of the fiber bundle, the arc-shaped protrusion of the first yarn spreading roller is opposite to the arc-shaped groove of the second yarn spreading roller, the arc-shaped groove of the second yarn spreading roller is opposite to the arc-shaped protrusion of the third yarn spreading roller, the arc-shaped groove of the first yarn spreading roller is opposite to the arc-shaped protrusion of the second yarn spreading roller, and the arc-shaped protrusion of the second yarn spreading roller is opposite to the arc-shaped groove of the third yarn spreading roller.

[0010] In some embodiments of the present invention, the fiber tow pretreatment system further comprises: A stirring device is provided on the bottom wall of the impregnation tank, and is used for stirring the impregnation liquid so that the resin particles are uniformly dispersed in the liquid.

[0011] In some embodiments of the present invention, the fiber tow pretreatment system further comprises: a first yarn separating device, arranged on an upstream side of the dipping tank along the traveling direction of the fiber tow; A second yarn separating device is provided between the dipping tank and the processing device.

[0012] In some embodiments of the present invention, the fiber tow pretreatment system further comprises: At least one guide roller is arranged between the first yarn separating device and the impregnation tank. The height of each guide roller is higher than the height of the notch of the impregnation tank. The guide roller is used to guide the direction of the fiber bundle.

[0013] In some embodiments of the present invention, the fiber tow pretreatment system further comprises: a draining roller, disposed between the impregnation tank and the second yarn separating device, and configured to drain excess impregnation liquid from the fiber bundle impregnated with the impregnation liquid; A guide plate is provided in the impregnation tank and is located below the leaching roller. The guide plate is used to guide the impregnation liquid leached by the leaching roller into the impregnation tank.

[0014] The technical solutions provided by the embodiments of the present invention may have the following beneficial effects: The present invention provides a fiber bundle pretreatment system, which contains an impregnation liquid including liquid and resin particles in an impregnation tank. When the fiber bundle passes through the impregnation tank, the resin particles can adhere to it. The fiber bundle with the resin particles is then heated by a processing device. The processing device can dry the liquid on the impregnated fiber bundle and convert the resin particles attached to the fiber bundle into target resin particles. The target resin particles are located between adjacent fiber filaments to form a guide channel. Then, when the resin is subsequently impregnated to prepare a prepreg, the resin can better enter the interior of the fiber bundle through the guide channel, thereby improving the resin impregnation effect and ensuring the quality of the prepreg.

[0015] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0017] Figure 1 is a structural schematic diagram of a fiber tow pretreatment system according to an exemplary embodiment; Figure 2 is a schematic diagram showing an arrangement of multiple yarn spreading rollers according to an exemplary embodiment; Figure 3 is a schematic structural diagram of a fiber bundle including target resin particles according to an exemplary embodiment.

[0018] Reference numerals: 10. Fiber tow; 20. Target resin particles; 30. Diversion channel; 100, creel; 200, yarn arrangement plate; 310, first yarn separating device; 320, second yarn separating device; 400, guide roller; 500, dipping tank; 510, yarn spreading roller; 5110, first yarn spreading roller; 5120, second yarn spreading roller; 5130, third yarn spreading roller; 520, body; 530, arc-shaped protrusion; 540, arc-shaped groove; 550, drain roller; 560, guide plate; 570, stirring device; 600, processing device; 610, drying furnace; 620, melting furnace; 630, shaping furnace; 6310, shaping assembly; 700. Loom. DETAILED DESCRIPTION

[0019] Exemplary embodiments are described in detail herein, with examples illustrated in the accompanying drawings. When the following description refers to the drawings, identical numerals in different figures represent identical or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present invention.

[0020] Prepreg is a composite of a resin matrix and reinforcement, made by impregnating continuous fibers or fabrics with a resin matrix. High-performance composite materials made from prepreg are widely used in aerospace, industrial manufacturing, sports equipment and other fields. Prepreg is obtained by impregnating continuous fibers with resin and then curing them. However, during the process of impregnating the fiber tows with resin, especially for heavyweight fabrics, a large number of fibers need to be stacked together for resin impregnation. This leads to insufficient impregnation, making it difficult for the resin to penetrate the interior of the fiber tows, affecting the quality of the prepreg and, in turn, the appearance, mechanical properties and durability of the finished fiber-reinforced resin material.

[0021] In order to solve the above technical problems, the present invention provides a fiber bundle pretreatment system, in which an impregnation liquid including liquid and resin particles is contained in an impregnation tank, and resin particles can adhere to the fiber bundle when the fiber bundle passes through the impregnation tank. The fiber bundle with resin particles attached is then heated by a processing device, and the processing device can dry the liquid on the impregnated fiber bundle and convert the resin particles attached to the fiber bundle into target resin particles. The target resin particles are located between adjacent fiber filaments to form a guide channel, and then, when the resin is subsequently impregnated to prepare a prepreg, the resin can better enter the interior of the fiber bundle through the guide channel, thereby improving the resin impregnation effect and ensuring the quality of the prepreg.

[0022] A fiber tow pretreatment system provided according to the present invention will be described in detail below with reference to the accompanying drawings.

[0023] It should be noted that the traveling direction of the fiber tow does not refer to the specific extension direction of the fiber at a certain device, but refers to the moving direction of the fiber tow as a whole. Figure 1 The positive direction of the x-axis is the direction of travel of the fiber tow 10, and the y-axis is the vertical direction. The movement of the fiber tow 10 is achieved by traction of a traction device (not shown in the figure); Figure 2 The coordinate axes in are only used to indicate the orientation. Figure 1 The x-axis and y-axis directions can be the same or different; in addition, the fiber tow 10 in the present invention refers to a fiber aggregate formed by multiple continuous single fibers arranged in parallel or lightly bonded, with a loose structure, weak bonding between single fibers, and no obvious twisting, which is easy to disperse, such as carbon fiber tow, glass fiber tow, etc.

[0024] The embodiment of the present invention provides a fiber tow pretreatment system, such as Figure 1 and Figure 3 As shown, it includes an impregnation tank 500 and a processing device 600. The impregnation tank 500 is filled with an impregnation liquid, which includes liquid and resin particles. The resin particles are insoluble in the liquid in which they are immersed. The liquid is used to disperse the resin particles therein, and then when the fiber bundle 10 passes through the impregnation liquid in the impregnation tank 500, the resin particles will adhere to the fiber bundle 10. The attachment here means that the resin particles are clamped between adjacent fiber filaments and on the surface of the fiber bundle 10; and the processing device 600 is arranged on the downstream side of the impregnation tank 500. When the fiber bundle 10 with resin particles attached enters the processing device 600, the processing device 600 can dry the liquid on the impregnated fiber bundle 10, and can convert the resin particles attached to the fiber bundle 10 into target resin particles 20. Each target resin particle 20 is bonded between adjacent fiber filaments so that adjacent fiber filaments are spaced apart to form a guide channel 30.

[0025] It can be understood that the resin particles can be thermoplastic resin particles or thermosetting resin particles, and the liquid can be water, methanol, ethanol, etc. For resin particles and liquids of different materials, the heating temperature of the processing device 600 can be adjusted accordingly; the size range of the resin particles is 10-20 microns, and the size here refers to the length of the longest side. The shape of the resin particles can be a cuboid, a sphere, or an irregular shape. The resin particles are randomly distributed between the fiber filaments, and the target resin particles 20 are resin particles processed according to demand to meet the required elasticity, hardness, shape and other requirements.

[0026] In this embodiment, by containing the impregnation liquid including liquid and resin particles in the impregnation tank 500, the resin particles can adhere to the fiber bundle 10 when passing through the impregnation tank 500, and the fiber bundle 10 with the resin particles attached thereto is then heated by the processing device 600. The processing device 600 can dry the liquid on the impregnated fiber bundle 10 and can convert the resin particles attached to the fiber bundle 10 into target resin particles 20. The target resin particles 20 are located between adjacent fiber filaments to form a guide channel 30. Then, when the resin is subsequently impregnated to prepare the prepreg, the resin can better enter the interior of the fiber bundle 10 through the guide channel 30, thereby improving the resin impregnation effect, reducing the porosity, and ensuring the quality of the prepreg. Experimental verification shows that the porosity of the fibers treated by the fiber bundle pretreatment system provided by the present invention is reduced by more than 6% compared with the untreated fibers directly used for the prepreg.

[0027] In one embodiment, continue to refer to Figure 1 and Figure 3 Along the traveling direction of the fiber bundle 10, the processing device 600 includes a drying furnace 610, a melting furnace 620 and a shaping furnace 630 arranged in sequence in the traveling direction of the fiber. The heating methods of the drying furnace 610, the melting furnace 620 and the shaping furnace 630 are, for example, fuel heating (gas, liquid, solid) and electric heating (resistance, induction), etc., which are not limited here.

[0028] The impregnated fiber bundle 10 first arrives at the drying furnace 610. Since the boiling point of the liquid is lower than the melting point of the resin particles, the heating temperature of the drying furnace 610 is set to be higher than the boiling point of the liquid, for example, 20-50°C higher than the boiling point of the liquid. The liquid on the fiber bundle 10 boils in the drying furnace 610 and is converted from liquid to gas, and the fiber bundle 10 is dried. The dried fiber bundle 10 enters the melting furnace 620. The heating temperature of the melting furnace 620 is lower than the melting point of the resin particles, for example, slightly lower than the melting point of the thermoplastic resin particles by 10-50°C. The heating temperature of the melting furnace 620 needs to be ensured. The surface of each resin particle melts but not all of it melts. The surface of the melted resin particle is sticky and can bond with the fiber filaments, ensuring the stability of the resin particle fixation; the fiber filament bundle 10 bonded with the resin particles enters the shaping furnace 630. The heating temperature of the shaping furnace 630 is higher than the glass transition temperature of the resin particles, for example, 20-100°C higher than the glass transition temperature of the thermoplastic resin particles. The shaping furnace 630 can transform the melted resin particles into target resin particles 20. The target resin particles 20 change in morphology compared to the resin particles, such as shape, elasticity, etc.

[0029] It should be noted that thermoplastic resins will undergo the following changes as the temperature rises: first, at low temperatures, they are in a glassy state, the molecular chains are in a frozen state, and the material is hard and brittle; as the temperature rises, the molecular chains begin to move, the interaction force weakens, and the material becomes soft and elastic, at this time in a highly elastic state; after the temperature reaches a certain level, the molecular chains move freely, and the material exhibits a flowing state, which is called a viscous flow state; this process is reversible, that is, a glassy thermoplastic resin can become a highly elastic state or a viscous flow state when heated, and can return to a glassy state after cooling; the critical temperature at which a thermoplastic resin material changes from a glassy state to a highly elastic state is called the glass transition temperature (Tg).

[0030] With such a design, after the fiber bundle 10 with thermoplastic resin particles attached is processed by the drying furnace 610, the melting furnace 620 and the shaping furnace 630, the target resin particles 20 can better fit between the fiber filaments, separating the fiber filaments in the fiber bundle 10 to form a guide channel 30. Subsequently, the fiber bundle 10 with the target resin particles 20 attached is woven by the loom 700 to prepare it into a reinforcement in the prepreg, and then impregnated with resin, which can improve the impregnation effect and ensure the quality of the finished product.

[0031] In another embodiment, the resin particles are thermosetting resin particles. As the temperature rises, the thermosetting resin undergoes the following changes: When the temperature rises above the glass transition temperature (Tg) of the thermosetting resin, the resin particles begin to soften, the mobility of the molecular segments increases, and the particles gradually lose their original shape, potentially experiencing slight melting or adhesion. When the temperature continues to rise above the crosslinking threshold, the resin solidifies, with the resin molecules completely crosslinked into a three-dimensional network structure, becoming a hard solid. Therefore, when the resin particles are thermosetting resin particles, the temperatures of the melting furnace 620 and the shaping furnace 630 of the processing device 600 should be set slightly above the glass transition temperature (Tg) of the thermosetting resin and below the curing temperature of the thermosetting resin, for example, 5-30°C above the glass transition temperature and below the curing temperature. At this point, the surface of the resin particles melts and adheres to the fiber filaments, and then passes through the shaping furnace 630 to set the shape.

[0032] In one embodiment, if Figure 1 and Figure 3As shown, the shaping furnace 630 includes a shaping furnace body and a shaping component 6310 arranged in the shaping furnace body. The shaping furnace body is used to gradually harden each resin particle melted by the melting furnace 620 to a target state. The target state is a state in which the elasticity, hardness, etc. of the resin particles are within a target range, that is, from a surface viscous flow state to a highly elastic state; the shaping component 6310 includes at least one group of pressing rollers, each group of pressing rollers can include two upper and lower pressing rollers in the y-axis direction, the pressing rollers can be set to have a heating function, and the heating temperature is equal to the temperature of the shaping furnace 630. The pressing rollers are used to roll the resin particles in the target state so that the resin particles in the target state are deformed into target resin particles 20.

[0033] By setting a pressing roller in the shaping furnace 630, the thickness of the fiber bundle 10 can be ensured to be uniform, which is convenient for subsequent weaving by the loom 700; in addition, the pressing roller can shape the resin particles to ensure that the resin particles and the fiber filaments fit better, and control the pores between the fiber filaments within a suitable range, avoiding the defect of resin-rich when the prepreg is subsequently made due to excessive pores.

[0034] In one embodiment, if Figure 1 As shown, since the fiber tow 10 is always in a forward state, the length of each furnace can be set according to the required reaction time. Specifically, the length of the drying furnace 610 is determined according to the time for the liquid in the fiber tow 10 to be completely vaporized and the moving speed of the fiber. The length of the melting furnace 620 is determined according to the time for the resin particles to melt on the surface at a set temperature and the moving speed of the fiber. The length of the shaping furnace 630 is determined according to the time for the resin particles to be converted into a highly elastic state at a set temperature and the moving speed of the fiber. For example: the moving rate of the carbon fiber tow 10 is 10-15m / h, and the lengths of the drying furnace 610, the melting furnace 620 and the shaping furnace 630 are 1.5m, 0.5m and 4m respectively. Those skilled in the art can make settings according to actual conditions to ensure sufficient reaction in each stage.

[0035] In one embodiment, if Figure 1 and Figure 2 As shown, at least one spreading roller 510 is provided in the impregnation tank 500. The spreading roller 510 is used to spread the fiber tow 10 so that the resin particles enter between adjacent fiber filaments. The provision of the spreading roller 510 not only limits the position of the fiber tow 10 but also spreads the fiber tow 10 in the impregnation liquid, ensuring that the resin particles enter between adjacent fiber filaments.

[0036] In one embodiment, if Figure 2 As shown, the yarn spreading roller 510 includes a body 520 and a plurality of arc-shaped protrusions 530 and a plurality of arc-shaped grooves 540 provided on the outer peripheral surface of the body 520. Figure 2The middle y-axis direction is the axial direction of the yarn spreading roller 510, and multiple arc-shaped protrusions 530 are arranged in sequence along the y-axis direction. Each arc-shaped groove 540 is located between adjacent arc-shaped protrusions 530, and the adjacent arc-shaped protrusions 530 and the arc-shaped grooves 540 are smoothly connected. Among them, each arc-shaped protrusion 530 and each arc-shaped groove 540 extends along the circumference of the main body 520 to be arranged around the main body 520, that is, the axially extending arc-shaped protrusion 530 is approximately a spherical structure or a rugby-shaped structure.

[0037] In this embodiment, the arc-shaped protrusion 530 and the arc-shaped groove 540 of the yarn guide roller have the same shape, both of which are one-quarter arcs. In other embodiments, the shapes of the arc-shaped protrusion 530 and the arc-shaped groove 540 may also be different. For example, the arc-shaped protrusion 530 may be longer in the axial direction of the main body 520, and the arc-shaped groove 540 may be shorter in the axial direction of the main body 520.

[0038] By providing the arc-shaped protrusion 530, the fiber bundle 10 can be dispersed when passing through the surface of the arc-shaped protrusion 530, ensuring that the resin particles can enter between the fiber filaments, and the arc-shaped groove 540 smoothly connected to the arc-shaped protrusion 530 can prevent the fiber filaments from being cut.

[0039] In one embodiment, if Figure 1 and Figure 2 As shown, at least one yarn spreading roller 510 includes a first yarn spreading roller 5110, a second yarn spreading roller 5120 and a third yarn spreading roller 5130. The first yarn spreading roller 5110, the second yarn spreading roller 5120 and the third yarn spreading roller 5130 are arranged in sequence and parallel to each other along the traveling direction of the fiber bundle 10; along the traveling direction of the fiber bundle 10, the arc-shaped protrusion 530 of the first yarn spreading roller 5110 is opposite to the arc-shaped groove 540 of the second yarn spreading roller 5120, and the arc-shaped groove 540 of the second yarn spreading roller 5120 is opposite to the arc-shaped protrusion 530 of the third yarn spreading roller 5130. The arc-shaped groove 540 of the first yarn spreading roller 5110 is opposite to the arc-shaped protrusion 530 of the second yarn spreading roller 5120, and the arc-shaped protrusion 530 of the second yarn spreading roller 5120 is opposite to the arc-shaped groove 540 of the third yarn spreading roller 5130.

[0040] With such a design, when multiple bundles of fiber tows 10 pass through the first spreading roller 5110, the second spreading roller 5120 and the third spreading roller 5130, each bundle of fibers is distributed in the arc-shaped protrusions 530 and the arc-shaped grooves 540 in the axial direction of the main body 520, and part of the fiber tows 10 are unfolded at the arc-shaped protrusions 530 of the first spreading roller 5110, and then are gathered at the arc-shaped grooves 540 of the second spreading roller 5120, and then are unfolded again at the arc-shaped protrusions 530 of the third spreading roller 5130. Similarly, another part of the fiber tows 10 are gathered at the arc-shaped grooves 540 of the first spreading roller 5110, and then are unfolded at the arc-shaped protrusions 530 of the second spreading roller 5120, and then are gathered again at the arc-shaped grooves 540 of the third spreading roller 5130. The convex and concave matching arrangement of the multiple yarn spreading rollers 510 not only ensures that the resin particles can fully enter the interior of the fiber bundle 10, but also limits the fiber bundle 10 in the axial direction, avoids the mixing of fibers from different bundles, and reduces the possibility of entanglement between fiber filaments.

[0041] In one embodiment, the shapes of the first spreading roller 5110 and the third spreading roller 5130 can be different. For example, the curvature of the arc-shaped groove 540 of the first spreading roller 5110 is greater than the curvature of the arc-shaped groove 540 of the third spreading roller 5130. In this way, the fiber bundle 10 can be spread to different degrees to ensure that resin particles of different sizes can enter the interior of the fiber bundle 10.

[0042] In one embodiment, if Figure 1 As shown, the fiber tow pretreatment system further includes a stirring device 570 disposed on the bottom wall of the impregnation tank 500. The stirring device 570 is used to stir the impregnation liquid to uniformly disperse the resin particles in the liquid. The stirring device 570 is configured, for example, as a plurality of coaxial blades driven by a motor to rotate to achieve stirring. A certain distance is required between the stirring device 570 and the yarn spreading roller 510 to prevent the stirring device 570 from damaging the fiber tow 10.

[0043] In this embodiment, by providing the stirring device 570 , it is possible to ensure that the resin particles do not settle at the bottom of the dipping tank 500 but are dispersed in the liquid, thereby ensuring the number of resin particles entering between the fiber filaments.

[0044] In one embodiment, if Figure 1As shown, surfactants and the like can be added to the liquid. Surfactants can effectively prevent the aggregation of resin particles through charge repulsion or spatial steric effect. The ratio between the mass of the resin particles and the mass of the liquid is in the range of 0.05-0.2; the fiber tow pretreatment system also includes a replenishing device, and a first sensor and a second sensor are provided in the impregnation tank 500. The first sensor and the second sensor are both electrically connected to the replenishing device. The first sensor is used to detect the density of the resin particles in the impregnation liquid. When the first sensor detects that the resin particles in the impregnation liquid are lower than the first set threshold, the replenishing device can replenish the resin particles into the impregnation liquid in time; the second sensor is used to detect the liquid level. When the second sensor detects that the liquid level in the impregnation tank 500 is lower than the second set threshold, the second set threshold is, for example, the vertical distance between the bottom of the impregnation tank 500 and the upper end of the yarn spreading roller 510, the replenishing device can replenish the liquid into the impregnation liquid in time.

[0045] In one embodiment, if Figure 1 As shown, the fiber bundle pretreatment system also includes a first yarn splitting device 310 and a second yarn splitting device 320. Along the traveling direction of the fiber bundle 10, the first yarn splitting device 310 is arranged on the upstream side of the impregnation tank 500, and can limit the fiber bundle 10 to ensure the position of the fiber bundle 10 on the yarn spreading roller 510; the second yarn splitting device 320 is arranged between the impregnation tank 500 and the processing device 600, and unfolds the fiber bundle 10 before heating to ensure that the fiber filaments or resin particles are evenly heated.

[0046] It can be understood that the first yarn separating device 310 and the second yarn separating device 320 can be any yarn separating device such as a yarn separating comb, a yarn separating plate, etc. that can organize and limit the fiber bundle 10, and are not limited here.

[0047] In one embodiment, if Figure 1 As shown, the fiber bundle pretreatment system also includes at least one guide roller 400. In this embodiment, two guide rollers 400 are provided. The guide rollers 400 are all arranged between the first yarn dividing device 310 and the impregnation tank 500. The height of each guide roller 400 is higher than the height of the notch of the impregnation tank 500. The guide rollers 400 are used to guide the direction of the fiber bundle 10.

[0048] By setting the height of each guide roller 400 higher than the height of the notch of the dipping tank 500, friction on the notch of the dipping tank 500 during movement of the fiber tow 10 is avoided, thereby avoiding wear of the fiber tow 10.

[0049] In one embodiment, if Figure 1As shown, the fiber bundle pretreatment system also includes a drain roller 550 and a guide plate 560. The drain roller 550 is arranged between the immersion tank 500 and the second yarn separation device 320. The drain roller 550 includes an upper roller and a lower roller arranged opposite to each other in the vertical direction. The upper roller and the lower roller are set to be made of rubber, for example. The lower roller is fixed. The height of the upper roller is adjustable in the vertical direction. After the fiber bundle 10 leaves the immersion tank 500, it passes between the upper roller and the lower roller. Different pressures are applied to the fiber bundle 10 by adjusting the height of the upper roller. force, for example, the pressure within the unit width is controlled at 30-60 kg / m, so as to ensure that the liquid is fully squeezed out without breaking the fibers; the excess impregnation liquid on the fiber bundle 10 impregnated with the impregnation liquid is drained away by the pressure between the upper roller and the lower roller, so as to avoid the excessive impregnation liquid being difficult to dry; the guide plate 560 is provided on the notch of the impregnation tank 500 and is located below the draining roller 550, and the guide plate 560 is used to drain the impregnation liquid drained by the draining roller 550 into the impregnation tank 500 for reuse, thereby saving the cost of raw materials.

[0050] In one embodiment, the guide plate 560 has an arc-shaped cross-section and a filter screen disposed therein. This design allows the drained impregnation liquid to collect at the bottom of the guide plate 560, preventing it from leaking or splashing out of the guide plate 560 and causing waste. The filter screen can filter out impurities, ensuring the impregnation effect of the impregnation liquid.

[0051] In one embodiment, the processing process of the fiber tow pretreatment system is as follows: First, the fiber bundles 10 on the yarn rack 100 are bundled and passed through the yarn arrangement plate 200 and the first yarn dividing device 310, and then pass through the upper part of the two guide rollers 400, enter the impregnation tank 500, and pass through the lower end of the first yarn spreading roller 5110, the upper end of the second yarn spreading roller 5120 and the lower end of the third yarn spreading roller 5130 in turn, and multiple bundles of fiber bundles 10 pass through the multiple arc-shaped protrusions 530 or the multiple arc-shaped grooves 540 of the first yarn spreading roller 5110, the second yarn spreading roller 5120 and the third yarn spreading roller 5130 respectively; then pass out from the extraction roller 550, pass through the second yarn dividing device 320, and pass through the drying furnace 610, the melting furnace 620 and the shaping furnace 630 in turn, and pass through the shaping component 6310 in the shaping furnace 630, and finally reach the loom 700.

[0052] Then, the traction equipment is started, and the fiber bundle 10 begins to move. After passing through the first yarn splitting device 310 and the two guide rollers 400, the impregnation is completed under the spreading action of the first yarn spreading roller 5110, the second yarn spreading roller 5120 and the third yarn spreading roller 5130 in the impregnation tank 500. The resin particles are attached to the fiber bundle 10, and then the excess impregnation liquid is drained by the draining roller 550. After being combed by the second yarn splitting device 320, the fiber bundle 10 enters the drying furnace 610, and is dried. The dried fiber bundle 10 enters the melting furnace 620, and the surface of each resin particle melts and bonds with the fiber filaments. The fiber bundle 10 bonded with resin particles enters the shaping furnace 630. The shaping furnace 630 can convert the molten resin particles into a highly elastic state, and then the resin particles in the target state are pressed by the pressure roller of the shaping component 6310 to deform the resin particles in the target state into target resin particles 20. After being processed in the shaping furnace 630 , the surface of the fiber tow 10 is smooth, the target resin particles 20 are firmly bonded and of appropriate size, and then enter the loom 700 for weaving, and the pretreatment process is completed.

[0053] In the present invention, the fiber bundle 10 is pretreated before manufacturing the prepreg, so that the resin particles and the fiber filaments are interconnected to form a guide channel 30. During the subsequent impregnation process, this porous structure allows the resin to better infiltrate into the interior of the fiber bundle 10, playing a role in interface toughening, thereby ensuring the appearance, mechanical properties and durability of the prepreg.

[0054] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, features defined as "first" or "second" may explicitly or implicitly include at least one of such features.

[0055] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0056] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0057] Other embodiments of the present invention will readily occur to those skilled in the art after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein.

Claims

1. A fiber tow pretreatment system, characterized in that: The fiber tow pretreatment system comprises: An impregnation tank containing an impregnation liquid, wherein the impregnation liquid includes liquid and resin particles, and the impregnation tank is used to impregnate fiber tows with the impregnation liquid, wherein the fiber tows impregnated with the impregnation liquid are attached with the resin particles; A processing device is arranged on the downstream side of the impregnation tank along the traveling direction of the fiber bundle. The processing device is used to dry the liquid on the impregnated fiber bundle and can convert the resin particles attached to the fiber bundle into target resin particles, and each of the target resin particles is located between adjacent fiber filaments so that adjacent fiber filaments are spaced apart to form a guide channel.

2. The fiber tow pretreatment system according to claim 1, characterized in that: The boiling point of the liquid is lower than the melting point of the resin particles, the resin particles are thermoplastic resin particles, and the processing device includes: a drying furnace, wherein the heating temperature of the drying furnace is higher than the boiling point of the liquid, and is used to dry the liquid on the fiber tow; a melting furnace, disposed downstream of the drying furnace along the traveling direction of the fiber filaments, the melting furnace having a heating temperature lower than the melting point of the resin particles, for partially melting each of the resin particles to bond with the fiber filaments; A shaping furnace is provided on the downstream side of the melting furnace along the traveling direction of the fiber bundle, and the heating temperature of the shaping furnace is higher than the glass transition temperature of the resin particles, so as to transform each of the resin particles melted by the melting furnace into the target resin particles.

3. The fiber tow pretreatment system according to claim 2, characterized in that: The shaping furnace comprises: a shaping furnace body, the shaping furnace body being used to gradually harden each of the resin particles melted by the melting furnace to a target state; A shaping assembly includes at least one set of pressing rollers, wherein the pressing rollers are used to press the resin particles in the target state so as to deform the resin particles in the target state into the target resin particles.

4. The fiber tow pretreatment system according to claim 1, characterized in that: The fiber tow pretreatment system also includes: At least one spreading roller is disposed in the impregnation tank and is used for spreading the fiber bundle so that the resin particles enter between adjacent fiber bundles.

5. The fiber tow pretreatment system according to claim 4, characterized in that: The yarn spreading roller includes a main body and a plurality of arc-shaped protrusions and a plurality of arc-shaped grooves arranged on the outer peripheral surface of the main body. The plurality of arc-shaped protrusions are distributed in sequence along the axial direction of the main body, and each of the arc-shaped grooves is respectively located between adjacent arc-shaped protrusions, and adjacent arc-shaped protrusions and arc-shaped grooves are smoothly connected, wherein each of the arc-shaped protrusions and each of the arc-shaped grooves extend along the circumference of the main body to be arranged around the main body.

6. The fiber tow pretreatment system according to claim 4, characterized in that: The at least one yarn spreading roller includes a first yarn spreading roller, a second yarn spreading roller and a third yarn spreading roller. The first yarn spreading roller, the second yarn spreading roller and the third yarn spreading roller are arranged in sequence along the traveling direction of the fiber bundle, and along the traveling direction of the fiber bundle, the arc-shaped protrusion of the first yarn spreading roller is opposite to the arc-shaped groove of the second yarn spreading roller, the arc-shaped groove of the second yarn spreading roller is opposite to the arc-shaped protrusion of the third yarn spreading roller, the arc-shaped groove of the first yarn spreading roller is opposite to the arc-shaped protrusion of the second yarn spreading roller, and the arc-shaped protrusion of the second yarn spreading roller is opposite to the arc-shaped groove of the third yarn spreading roller.

7. The fiber tow pretreatment system according to claim 1, characterized in that: The fiber tow pretreatment system also includes: A stirring device is provided on the bottom wall of the impregnation tank, and is used for stirring the impregnation liquid so that the resin particles are uniformly dispersed in the liquid.

8. The fiber tow pretreatment system according to any one of claims 1 to 7, characterized in that: The fiber tow pretreatment system also includes: a first yarn separating device, arranged on an upstream side of the dipping tank along the traveling direction of the fiber tow; A second yarn separating device is provided between the dipping tank and the processing device.

9. The fiber tow pretreatment system according to claim 8, characterized in that: The fiber tow pretreatment system also includes: At least one guide roller is arranged between the first yarn separating device and the impregnation tank. The height of each guide roller is higher than the height of the notch of the impregnation tank. The guide roller is used to guide the direction of the fiber bundle.

10. The fiber tow pretreatment system according to claim 8, characterized in that: The fiber tow pretreatment system also includes: a draining roller, disposed between the impregnation tank and the second yarn separating device, and configured to drain excess impregnation liquid from the fiber bundle impregnated with the impregnation liquid; A guide plate is provided in the impregnation tank and is located below the leaching roller. The guide plate is used to guide the impregnation liquid leached by the leaching roller into the impregnation tank.

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