Fiber composite material extrusion molding preparation device and fiber composite preform

Abstract

The invention relates to the technical field of composite material preparation, and discloses a fiber composite material extrusion molding preparation device and a fiber composite prefabricated body, the fiber composite material extrusion molding preparation device comprises a feeding assembly, the feeding assembly comprises a cavity, and a feeding port is formed in one side of the cavity; the scattering assembly comprises a first scattering part and a second scattering part, the first scattering part is used for scattering the short fibers to remove impurities, and the second scattering part is used for carrying out airflow scattering on the short fibers; the mixing assembly comprises a mixing box, a conveying part and a mixing part, a buffer bin is arranged between the cavity and the mixing box, the conveying part is arranged in the mixing box and used for conveying the scattered short fibers, and the mixing part is arranged in the mixing box and used for mixing the short fibers and resin; and the forming assembly comprises an extruder and an adjusting part, the extruder communicates with the discharging opening of the mixing box, the adjusting part is arranged on the extruder, and the extruder is matched with the adjusting part to be used for extruding products of different shapes. The scattering effect of short fibers and uniform mixing of the short fibers and resin are guaranteed, and meanwhile the extrusion shape is convenient to adjust.

Description

Technical Field

[0001] This invention relates to the field of composite material preparation technology, and in particular to a fiber composite material extrusion molding preparation device and a fiber composite preform. Background Technology

[0002] Fiber composites, especially resin-based composites with short fibers (such as carbon fiber, glass fiber, and biomass fiber) as reinforcement, have been widely used in the automotive, construction, aerospace, and consumer goods industries due to their excellent specific strength, designability, and processing flexibility. Their performance is highly dependent on the uniformity of fiber dispersion, orientation distribution, and interfacial bonding quality within the resin matrix. However, existing extrusion molding technologies for short fiber composites still face the following key bottlenecks that urgently need to be addressed: 1. Incomplete fiber dispersion easily leads to "agglomeration" defects: Existing equipment mostly uses single-stage mechanical stirring or screw shearing to disperse fibers, which is a simple and crude method. For short fibers, especially biomass fibers, which are prone to entanglement and contain impurities, traditional dispersing rollers or stirring blades can only perform macroscopic breaking, making it difficult to achieve effective "monofilament" dissociation of fiber bundles. Insufficiently dissociated fiber clumps ("fiber agglomerates") act as stress concentration points in subsequent processes, not only severely degrading the mechanical strength and toughness of the product, but also causing appearance defects such as "white spots" and "cloudy patterns" on the product surface, affecting the commodity value.

[0003] 2. Macroscopic and microscopic inhomogeneities exist in fiber-resin blending: blending processes often rely on melt blending with screw extruders or static mixers. The former can easily cause excessive fiber shearing and aspect ratio loss at high fiber contents; the latter has flow dead zones, where fibers tend to deposit in specific areas, resulting in uneven fiber distribution within the product cross-section (i.e., "segregation"). This inhomogeneity makes the material properties anisotropic, with poor batch stability, making it difficult to meet the requirements of high-precision structural components.

[0004] 3. Poor controllability of fiber addition process affects process stability: Most equipment directly and in batches adds the dispersed fibers into the resin melt, creating instantaneous local high fiber concentration zones. This not only exacerbates fiber entanglement but also requires longer homogenization time and higher energy consumption in the initial mixing stage. The lack of precise control over the stable, uniform, and dispersed addition of fibers to the resin is a major process challenge restricting the efficient production of high-quality composite materials.

[0005] 4. Insufficient molding flexibility and low equipment intelligence: Traditional extrusion molding dies are cumbersome to change, making it impossible to quickly switch between products with different cross-sectional shapes, and the production mode of small batches and multiple specifications is costly. At the same time, existing equipment often lacks integrated solutions for controlling resin volatiles and dust pollution during the mixing process, as well as the coordinated control of mixing temperature and feeding sequence, which affects the consistency of the production environment and products.

[0006] Therefore, developing an integrated preparation device that can achieve deep fiber dispersion and impurity removal, precise and controllable addition, efficient and uniform mixing, and flexibly adapt to the molding needs of diverse products is an urgent technical and industrial need for improving the quality of short fiber composite products and expanding their application fields. Summary of the Invention

[0007] The purpose of this invention is to provide a fiber composite material extrusion molding preparation device and a fiber composite preform to solve the problems existing in the prior art.

[0008] To achieve the above objectives, the present invention provides the following solution: The present invention provides a fiber composite material extrusion molding preparation apparatus, comprising: The feeding assembly includes a cavity, and a feeding port is provided on one side of the cavity; The dispersing component includes a first dispersing element and a second dispersing element. The first dispersing element is disposed at the feed end of the feed inlet and is used to disperse and remove impurities from the short fibers. The second dispersing element is disposed in the cavity and is used to disperse the short fibers by airflow. A mixing assembly includes a mixing chamber, a conveying component, and a mixing component. The mixing chamber is connected to the cavity, and a buffer chamber is provided between the cavity and the mixing chamber. The buffer chamber is connected to a negative pressure suction fan and is used to convey the dispersed short fibers from the cavity to the mixing chamber under negative pressure. The conveying component is disposed in the mixing chamber and is used to uniformly convey the dispersed short fibers. The mixing component is disposed in the mixing chamber and is used to mix the short fibers and resin. The molding assembly includes an extruder and an adjusting component. The extruder is connected to the discharge port at the bottom of the mixing chamber, and the adjusting component is located at the output end of the extruder. The extruder, in conjunction with the adjusting component, is used to extrude products of different shapes.

[0009] Preferably, the first disintegrating component includes a cleaning box connected to the feed inlet. A first conveyor belt and a second conveyor belt are installed inside the cleaning box. The first conveyor belt and the second conveyor belt form a zigzag conveying path. Two rotating shafts are rotatably connected inside the cleaning box. Disintegrating rollers are fixedly connected to the rotating shafts. The two disintegrating rollers are respectively located directly above the first conveyor belt and the second conveyor belt. Several steel needles are fixedly connected to the disintegrating rollers.

[0010] Preferably, permanent magnet blocks are fixedly connected to the ends of both the first conveyor belt and the second conveyor belt.

[0011] Preferably, the bottom of the cavity is provided with an air inlet, which is connected to an external fan. The second dispersing component includes a gas conveying plate fixedly connected to the bottom of the cavity, which is connected to the air inlet. The top of the gas conveying plate is provided with several air outlets. An electric heating wire is fixedly connected inside the gas conveying plate. A baffle is fixedly connected inside the cavity. The top of the cavity is provided with several filter ports.

[0012] Preferably, the conveying component includes a conveying trough with open top and bottom ends. Two connecting rods are fixedly connected to one end of each end of the conveying trough, and the other end of the connecting rods extends out of the mixing box. A receiving component is provided inside the conveying trough for receiving the dispersed short fibers. A vibrating component is provided inside the mixing box for driving the conveying trough to vibrate, so that the received short fibers are spread flat on the receiving component. The receiving component is used to uniformly convey the short fibers into the resin below.

[0013] Preferably, the vibrating element is fixedly connected to a support frame on the inner side wall of the mixing box. A cam is rotatably connected to the support frame via a motor. The cam is in contact with one end of the conveying groove. One end of the connecting rod extends out of the mixing box and is fixedly connected to a limit block. A first spring is sleeved on the connecting rod. The two ends of the first spring are in contact with the limit block and the support frame, respectively.

[0014] Preferably, the receiving component includes a receiving belt, and the inner walls of the conveying trough are provided with grooves on opposite sides. A sliding rod is fixedly connected in the groove, and a slider is slidably connected on the sliding rod. A support roller is rotatably connected between two opposing sliders, and the receiving belt is sleeved on the two support rollers. A second spring is sleeved on both ends of the sliding rod, and the two ends of the second spring are fixedly connected to the inner wall of the groove and the slider, respectively. A first electric telescopic rod and two guide rollers are fixedly connected to the inner wall of the conveying trough. A drive roller is installed at the telescopic end of the first electric telescopic rod. The drive roller is located in the middle of the conveying trough and is in contact with the inner wall of the receiving belt. The two guide rollers are located on both sides of the drive roller and are in contact with the outer wall of the receiving belt.

[0015] Preferably, the bottom of the mixing chamber is provided with a heating layer and a heat insulation layer, the upper part of the mixing chamber is provided with a shielding structure for limiting the rise of resin vapor, and the mixing chamber is provided with an exhaust port connected to an exhaust fan.

[0016] Preferably, the adjusting component includes a fixed disk, which is fixedly connected to the output end of the extruder. The fixed disk has a communication port in the middle, which is connected to the output end of the extruder. The fixed disk has several slides along the axial direction, and extrusion disks are slidably connected to the slides through threaded rods. The extrusion ports on the several extrusion disks have different shapes.

[0017] A fiber composite preform, the preform being prepared by a fiber composite material extrusion molding apparatus.

[0018] Compared with existing technologies, The fiber composite material extrusion molding preparation device provided by this invention, through its innovative systematic design, brings the following significant beneficial effects: 1. The "two-stage deep dispersal and online impurity removal" mechanism of fibers improves the uniformity of material properties: Primary mechanical combing and separation: Through the cooperation of the dispersing roller with steel needles in the first dispersing component and the zigzag conveying path, the fibers are punctured and combed multiple times and at multiple angles to disassemble the fiber bundles. The permanent magnet block at the end of the conveyor belt is used to adsorb and remove metal impurities, thus achieving the initial separation and purification of the fibers.

[0019] Secondary airflow expansion and drying: Heated airflow is evenly sprayed from the gas conveying plate through the second dispersing component to flexibly expand and disperse the falling fibers, further separating any small agglomerates that may remain after mechanical dispersion; the hot air also serves as a dryer, thereby reducing the problem of uneven mixing caused by high fiber moisture content; the baffle plate is used to improve the airflow distribution within the cavity.

[0020] 2. Vibration spreading and gentle feeding mechanism achieves uniform fiber dispersion: Uniform spreading: The high-frequency micro-vibration of the conveyor trough is driven by a vibrating component, which causes the fibers falling into it to be spread into a relatively uniform thin layer on the receiving belt, thereby alleviating the problem of fibers clumping together due to their own weight.

[0021] Gentle feeding: The position of the drive roller is adjusted by the first electric telescopic rod, causing the receiving belt with the fiber layer to deform gently, thus allowing the fibers to fall into the resin melt below in a large area, softly and continuously. This method avoids sudden fiber accumulation and excessively high local concentration, providing a more uniform initial distribution for subsequent mixing.

[0022] 3. Zoned temperature control and steam extraction system optimize the mixing environment: Efficient mixing and stable temperature: The heating and insulation layers at the bottom of the mixing chamber ensure that the resin is in the optimal and stable processing temperature range, which is beneficial to resin flow and fiber impregnation.

[0023] Steam barrier and extraction: The shielding structure at the top of the mixing chamber (such as the cover plate, baffle, and enclosure in the embodiment) works in conjunction with the exhaust fan to effectively limit and actively extract the volatile vapors generated by the resin when heated, reducing the possibility of them condensing and adhering to upstream components. This protects the equipment, maintains the cleanliness of some areas inside the mixing chamber, and improves process stability and environmental friendliness.

[0024] 4. Modular and rapid switching of molding solutions improves production flexibility and efficiency: By using multiple extrusion discs with different extrusion nozzle shapes that slide together in the adjusting mechanism, and driven by a threaded rod, extrusion dies can be quickly changed without stopping the machine or with only a short stop. This greatly meets the production needs of multi-variety, small-batch orders, reduces downtime and labor costs for die changes, and improves the overall utilization rate of the equipment.

[0025] 5. It is beneficial to obtain fiber composite preforms with uniform structure: Based on the synergistic design of the device in the fiber dispersing, conveying, spreading and mixing process of the present invention, the short fibers are in a relatively dispersed and stable state before entering the resin. As a result, the fibers in the preform prepared by the device of the present invention exhibit a relatively uniform spatial distribution in the resin matrix, reducing fiber agglomeration and local enrichment. This provides a uniform raw material basis for subsequent molding or curing processes, which is beneficial to improving the overall performance consistency of the final composite material product. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the internal structure of the impurity removal box of the present invention; Figure 3 This is a schematic diagram of the internal structure of the cavity in this invention; Figure 4 This is a schematic diagram of the internal structure of the mixing box of the present invention; Figure 5 This is a schematic diagram of the internal structure of the conveying trough of the present invention; Figure 6 This is a schematic diagram of the slide rail distribution within the fixed disc of the present invention; Figure 7 This is a schematic diagram of the overall structure of Embodiment 2 of the present invention; Figure 8 This is a schematic diagram of the overall structure of Embodiment 3 of the present invention; Figure 9 This is a schematic diagram of the fiber feeding state in Embodiment 3 of the present invention; The components include: 1. Cavity; 2. Feed inlet; 3. Mixing box; 4. Extruder; 5. Discharge port; 6. Impurity removal box; 7. First conveyor belt; 8. Second conveyor belt; 9. Rotating shaft; 10. Dispersing roller; 11. Steel needle; 12. Extrusion disc; 13. Air inlet; 14. External fan; 15. Gas conveying plate; 16. Air outlet; 17. Electric heating wire; 18. Baffle plate; 19. Filter port; 20. Conveying trough; 21. Connecting rod; 22. Support frame; 23. Motor; 24. Cam; 25. Limiting block; 26. First spring; 27. Receiving belt. ; 28. Slide rail; 29. ​​Slider; 30. Support roller; 31. First electric telescopic rod; 32. Guide roller; 33. Drive roller; 34. Slide rod; 35. Second spring; 36. Stirring shaft; 37. Fixed plate; 38. Connecting port; 39. Slide track; 40. Threaded rod; 41. Insulation layer; 42. Heating layer; 43. Cover plate; 44. Cover body; 45. Baffle; 46. Exhaust fan; 47. Second electric telescopic rod; 48. Third electric telescopic rod; 49. Buffer chamber; 50. First valve; 51. Second valve; 52. Negative pressure suction fan. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Biomass composite materials are high-biocarbon composite materials made primarily from renewable natural plant fibers, mixed with thermoplastic resins and appropriate additives through compounding and extrusion. This material not only possesses the texture of natural plant fibers but can also be processed using techniques similar to solid wood. It has wide applications in building materials, packaging, logistics pallets, and other fields, and is gradually gaining acceptance.

[0030] A biomass composite material molding device and process are disclosed in related technologies. The device includes a plastic hopper, a screw extruder connected below the plastic hopper, a sheet die connected to the end of the screw extruder, a plastic sheet extruded from the sheet die outlet, a fiber layer laid on the plastic sheet, a composite plate attached to the end of the plastic sheet, a fiber hopper on the upper part of the plastic sheet, and a pressure roller disposed above the fiber layer and a support roller disposed below the plastic sheet. This device and process can produce biomass composite materials with a biomass fiber filling content of up to 60%, without the reduction in aspect ratio caused by shearing of plant fibers. The composite material is 45% higher than that of traditional blending extrusion molding. The single extrusion molding structure in the aforementioned related technologies cannot meet the continuous production needs of multi-specification products, requiring frequent adjustments to equipment parameters. At the same time, there is no technical structure and effect of uniform mixing of short fibers and resin, affecting the final product quality. In order to solve the above problems, this invention is proposed.

[0031] In this invention, the short fibers can be inorganic fibers, organic fibers, or combinations thereof, preferably one or more of carbon fibers, glass fibers, basalt fibers, and aramid fibers. The length of the short fibers is 1–20 mm, preferably 3–12 mm, and the fiber diameter is 5–20 μm.

[0032] The resin can be a thermoplastic resin, a thermosetting resin, or a blend of the two. Examples of thermoplastic resins include polypropylene (PP), polyethylene (PE), polyamide (PA), polyphenylene sulfide (PPS), and polyetheretherketone (PEEK); examples of thermosetting resins include epoxy resin, phenolic resin, unsaturated polyester resin, bismaleimide resin, or cyanate ester resin.

[0033] In some embodiments, appropriate amounts of toughening agents, coupling agents, lubricants, stabilizers, flame retardants, or fillers may be added to the resin to improve the processing or performance of the composite material.

[0034] Example 1: Reference Figures 1-6 This invention provides a fiber composite material extrusion molding preparation apparatus, comprising: The feeding assembly includes a cavity 1, and a feeding port 2 is provided on one side of the cavity 1; The dispersing component includes a first dispersing component and a second dispersing component. The first dispersing component is disposed at the feed end of the feed inlet 2 and is used to disperse and remove impurities from the short fibers. The second dispersing component is disposed in the cavity 1 and is used to disperse the short fibers by airflow. The mixing assembly includes a mixing box 3, a conveying component, and a mixing component. The mixing box 3 is connected to the cavity 1. A buffer chamber 49 is provided between the cavity 1 and the mixing box 3. The buffer chamber 49 is connected to a negative pressure suction fan 52 and is used to convey the dispersed short fibers from the cavity 1 to the mixing box 3 under negative pressure. The conveying component is set inside the mixing box 3 and is used to uniformly convey the dispersed short fibers. The mixing component is set inside the mixing box 3 and is used to mix the short fibers and resin. The molding assembly includes an extruder 4 and an adjusting component. The extruder 4 is connected to the discharge port 5 at the bottom of the mixing box 3. The adjusting component is located at the output end of the extruder 4. The extruder 4, in conjunction with the adjusting component, is used to extrude products of different shapes.

[0035] In one embodiment of the present invention, during use, the fiber material is first initially dispersed by a first dispersing component. The fibers move along a zigzag conveying path formed by the first and second conveyor belts and undergo multiple mechanical combing processes under the action of the dispersing rollers and their steel needles, gradually breaking down the fiber bundles. Simultaneously, a permanent magnet block at the end of the conveyor belt is used to adsorb and remove any mixed metal impurities. The short fibers after primary dispersal are then conveyed into cavity 1 and further dispersed by a second dispersing component. The second dispersing component evenly sprays heated airflow through a gas conveying plate, causing the fibers to be suspended or semi-suspended within the cavity. Under the action of the flexible airflow, any small agglomerates that may remain after mechanical dispersal are further separated. At the same time, the fibers are heated and dried. A baffle plate is provided within the cavity to improve airflow distribution.

[0036] The dispersed fibers are conveyed to the mixing chamber 3 via connecting pipes and an external negative pressure suction fan 52. A buffer chamber between the cavity 1 and the mixing chamber 3 acts as a transition and flow stabilizer for the fibers, allowing them to enter the mixing chamber 3 in a relatively stable state. Once inside the mixing chamber 3, the fibers form a relatively uniform spread layer under the vibration of the conveying components and are then carried by the receiving components and evenly conveyed to the resin below, thus preventing fiber accumulation. Subsequently, the mixing components drive the resin to flow axially and radially, gradually coating and fully mixing the short fibers within the resin. The mixed material is then extruded through the extruder 4. During extrusion, the shape of the extruded product can be adjusted using adjustable components to obtain the desired cross-sectional shape.

[0037] As an optional implementation, the first disintegrating component includes a cleaning box 6, which is connected to the feed inlet 2. A first conveyor belt 7 and a second conveyor belt 8 are installed inside the cleaning box 6. The first conveyor belt 7 and the second conveyor belt 8 form a zigzag conveying path. Two rotating shafts 9 are rotatably connected inside the cleaning box 6. Disintegrating rollers 10 are fixedly connected to the rotating shafts 9. The two disintegrating rollers 10 are located directly above the first conveyor belt 7 and the second conveyor belt 8, respectively. Several steel needles 11 are fixedly connected to the disintegrating rollers 10.

[0038] In one embodiment of the present invention, the three-dimensional dispersion of fibers is achieved by extending the material conveying path to increase the dispersing time and combining it with the piercing and dispersing by the steel needle 11.

[0039] As an optional implementation, permanent magnet blocks are fixedly connected to the ends of both the first conveyor belt 7 and the second conveyor belt 8.

[0040] In one embodiment of the present invention, a permanent magnet adsorption unit is provided at the end of the conveyor belt, which can efficiently capture metal impurities and avoid the influence of metal impurities on the performance of composite materials.

[0041] As an optional implementation, the bottom of the cavity 1 is provided with an air inlet 13, which is connected to an external fan 14. The second dispersing component includes a gas conveying plate 15 fixedly connected to the bottom of the cavity 1. The gas conveying plate 15 is connected to the air inlet 13. Several air outlets 16 are provided at the top of the gas conveying plate 15. An electric heating wire 17 is fixedly connected inside the gas conveying plate 15. A baffle plate 18 is fixedly connected inside the cavity 1. Several filter ports 19 are provided at the top of the cavity 1.

[0042] In one embodiment of the present invention, the air inlet 13 is connected to an external fan 14, and a high-speed airflow is ejected through the air outlet 16 of the gas conveying plate 15. Combined with the hot air drying function of the electric heating wire 17, secondary dispersing and drying of the fibers are achieved, preventing fiber clumping. The baffle plate 18 is fixed on the inner wall of the cavity 1 to optimize the airflow distribution and ensure that there are no dead corners for dispersing within the cavity. The top filter device realizes dust recovery and exhaust gas purification, which meets the requirements of environmental protection production. The preferred filter device is a bag filter. The specific specifications and models can be selected by those skilled in the art according to actual needs, and are not specifically limited here.

[0043] As an optional implementation, the conveying component includes a conveying trough 20 with open top and bottom. Two connecting rods 21 are fixedly connected to one end of each end of the conveying trough 20, and the other end of the connecting rods 21 extends out of the mixing box 3. A receiving component is provided inside the conveying trough 20 to receive the broken short fibers. A vibrating component is provided inside the mixing box 3 to drive the conveying trough 20 to vibrate, so that the received short fibers are laid flat on the receiving component. The receiving component is used to uniformly convey the short fibers into the resin below.

[0044] In one embodiment of the present invention, the fiber material in the cavity 1 is conveyed to the mixing box 3 by a negative pressure suction fan 52. The conveying trough 20 is used to receive the dispersed fibers and achieve uniform fiber distribution through vibration. The receiving element ensures that the evenly distributed fibers are uniformly distributed to the resin below, thereby avoiding accumulation and ensuring the mixing effect in the later stage. The negative pressure suction fan 52 can be selected by those skilled in the art according to actual needs, and is not specifically limited here. In some embodiments, the negative pressure range generated by the negative pressure suction fan 52 can be -0.5kPa to -10kPa, preferably -1kPa to -5kPa, to achieve stable conveying of the dispersed short fibers. The buffer chamber can form a transition space between the cavity and the mixing box, making the fiber conveying process smoother. On the one hand, it can avoid the fibers from directly entering the mixing box in a pulse form and causing instantaneous accumulation; on the other hand, the stable suction provided by the negative pressure suction fan is conducive to controlling the fiber conveying speed, thereby improving the overall continuity and stability of the system.

[0045] As an optional implementation, the vibrating element is fixedly connected to the support frame 22 on the inner side wall of the mixing box 3. A cam 24 is rotatably connected inside the support frame 22 via a motor 23. The cam 24 is in contact with one end of the conveying groove 20. One end of the connecting rod 21 extends out of the mixing box 3 and is fixedly connected to a limit block 25. A first spring 26 is sleeved on the connecting rod 21. The two ends of the first spring 26 are in contact with the limit block 25 and the support frame 22, respectively.

[0046] In one embodiment of the present invention, the cam 24 and the first spring 26 drive the conveying groove 20 to reciprocate and vibrate, thereby achieving uniform spreading of short fibers in the resin.

[0047] The receiving component includes a receiving belt 27. Slide grooves 28 are provided on opposite side walls of the conveying trough 20. A slide rod 34 is fixedly connected within the slide groove 28. A slider 29 is slidably connected to the slide rod 34. A support roller 30 is rotatably connected between two opposing sliders 29. The receiving belt 27 is sleeved on the two support rollers 30. A second spring 35 is sleeved at both ends of the slide rod 34. The two ends of the second spring 35 are fixedly connected to the inner wall of the slide groove 28 and the slider 29, respectively. A first electric telescopic rod 31 and two guide rollers 32 are fixedly connected to the inner wall of the conveying trough 20. A drive roller 33 is installed at the telescopic end of the first electric telescopic rod 31. The drive roller 33 is located in the middle of the conveying trough 20 and contacts the inner wall of the receiving belt 27. The two guide rollers 32 are located on both sides of the drive roller 33 and contact the outer wall of the receiving belt 27.

[0048] In one embodiment of the present invention, the receiving belt 27 is used to receive short fibers. In the initial state, it is in contact with the inner wall of the conveying trough 20, and a trough structure is formed on the upper layer. The fibers are spread out by uniform shaking. After spreading out, the receiving belt 27 is deformed by the first electric telescopic rod 31, so that its two sides gradually shrink, so that the spread fibers are evenly spread and fall onto the resin below, ensuring the mixing effect in the later stage. The slider 29 is reset and retracted by the second spring 35.

[0049] As an optional implementation, the bottom of the mixing chamber 3 is provided with a heating layer 42 and a heat insulation layer 41, the upper part of the mixing chamber 3 is provided with a shielding structure for limiting the rise of resin vapor, and the mixing chamber 3 is provided with an exhaust port connected to the exhaust fan 46.

[0050] In one embodiment of the present invention, the mixing component includes a stirring shaft 36 rotatably connected within a mixing chamber 3. A circulation channel is provided within the stirring shaft 36, and the circulation channel is connected to an external water source. During the mixing process, the rotation of the stirring shaft causes the resin to flow axially and radially, gradually coating and dispersing the short fibers entering the resin. Because the fibers are already in a relatively uniformly spread state before entering the resin, re-agglomeration between fibers can be reduced, improving the uniformity of fiber dispersion in the resin matrix.

[0051] In one embodiment of the present invention, a resin inlet is provided at the front or rear end of the mixing tank 3. After the resin is input, the stirring shaft 36 is used to mix and stir the resin and fiber. The stirring shaft 36 is controlled to rotate by a separate motor. The stirring shaft 36 has a built-in circulation channel connected to an external water source. The stirring shaft 36 is prevented from overheating by introducing an external cold water source.

[0052] As an optional implementation, the adjusting component includes a fixed plate 37, which is fixedly connected to the output end of the extruder 4. A connecting port 38 is provided in the middle of the fixed plate 37. The connecting port 38 is fixedly connected to and communicates with the output end of the extruder 4 through a flange. Several slides 39 are provided on the fixed plate 37 along the axial direction. Extrusion discs 12 are slidably connected in the slides 39 through threaded rods 40. The extrusion ports on the several extrusion discs 12 are all different in shape.

[0053] In one embodiment of the present invention, the fixed disk 37 drives the extrusion disk 12 to slide along the slide 39 via the threaded rod 40, and the rapid switching of different extrusion nozzle shapes such as circles and rectangles can meet the production needs of products with multiple specifications.

[0054] As a specific control method example of the above-mentioned workflow, the operation steps are as follows: short fiber material enters the impurity removal box 6, the first conveyor belt 7 and the second conveyor belt 8 start to form a zigzag conveying path, the short fiber passes through the dispersing rollers 10 set on the two rotating shafts 9 in sequence during the conveying process, the two dispersing rollers 10 rotate under the drive of the rotating shafts 9, the steel needles 11 on the dispersing rollers 10 pierce and disperse the fiber, the permanent magnet blocks (not shown in the figure) set at the ends of the first conveyor belt 7 and the second conveyor belt 8 synchronously capture metal impurities, and the dispersed and impurity-removed fiber moves with the conveyor belt and enters the cavity 1; After the fibers enter the cavity 1, the first valve 50 is closed, and the external fan 14 and electric heating wire 17 are turned on. Air is supplied to the gas conveying plate 15 through the air inlet 13. The gas enters the cavity 1 through the air outlet 16 on the gas conveying plate 15, causing airflow disturbance to the short fibers in the cavity 1. At the same time, the electric heating wire 17 heats the airflow, which further disperses and dries the fibers. The dust and exhaust gas generated during the dispersion process are discharged through the filter port 19 at the top of the cavity 1 and are recovered and purified by the bag filter (not shown in the figure). The negative pressure suction fan 52 is started, which puts the buffer chamber 49 between the cavity 1 and the mixing box 3 into a negative pressure state. The fibers that have been broken up in the cavity 1 are transported through the pipeline to the buffer chamber 49 on the mixing box 3. The negative pressure suction fan 52 is turned off and the second valve 51 is opened, so that the fibers fall into the conveying trough 20. Simultaneously, the motor 23 drives the cam 24 to rotate, pushing one end of the conveying trough 20. With the reset action of the first spring 26, the conveying trough 20 reciprocates and vibrates. Under the vibration, the fiber is spread evenly on the receiving belt 27. After the spreading is completed, the conveying trough 20 stops reciprocating and vibrates. The second valve 51 is closed, the first electric telescopic rod 31 extends, and pushes the drive roller 33 to deform the receiving belt 27. At the same time, the guide roller 32 guides the receiving belt 27 to move. The spread fiber falls evenly into the resin below the mixing box 3. As the fiber falls, the stirring shaft 36 rotates to dynamically stir the fiber and resin. The mixed material enters the extruder 4 from the discharge port 5 at the bottom of the mixing box 3 and is conveyed forward under the action of the extruder 4. Extrusion discs 12 with different extrusion nozzle shapes are selected and installed on the fixed plate 37 as needed. The extrusion discs 12 are driven to slide along the slide 39 by the threaded rod 40 to complete the cross-section switching, so that the material is extruded by the extruder 4 to form products with corresponding cross-sectional shapes.

[0055] A fiber composite preform is prepared by a fiber composite material extrusion molding preparation device.

[0056] Example 2: Reference Figure 7In this embodiment, the shielding structure includes a cover plate 43. The two cover plates 43 are hinged to the insulation layer 41 via a second electric telescopic rod 47. At the same time, an exhaust port can be reserved on the side wall of the mixing box to install an exhaust fan 46 for removing excess resin vapor. When the conveying trough 20 reciprocates to lay the fibers, the cover plate 43 is in a closed state, and the resin material is simultaneously heated by the heating device and kept in a molten state. When feeding, the cover plate 43 is in an open state. As the fibers fall, the stirring shaft 36 rotates to dynamically stir the fibers and resin. The exhaust fan 46 is simultaneously turned on at low speed to remove excess resin vapor. When feeding is completed and the mixture is further stirred thoroughly, the cover plate 43 is in a closed state to prevent hot resin from evaporating, rising and condensing into other components above the mixing box 3.

[0057] Example 3: Reference Figures 8-9 The difference between this embodiment and embodiment two is that the mixing box 3 and the conveying trough 20 are rectangular cavities, and the shielding structure provided on the upper part of the mixing box 3 to limit the rise of resin vapor also includes a cover 44 and an expandable baffle 45.

[0058] In this embodiment, the cover 44 is a shell structure extending along the length of the conveying trough 20, covering the working area of ​​the conveying trough 20 used to carry the receiving component. The cover 44 is fixedly installed on the inner wall or top of the mixing box 3, located above the conveying trough 20, thereby forming a shielding space above the conveying trough 20. The installation position of the cover 44 leaves a gap between its lower edge and the side wall of the conveying trough 20 to avoid contact interference between the cover 44 and the conveying trough 20 during vibration. Four baffles 45 are hinged to the inner side wall of the mixing box 3 via a third electric telescopic rod 48. When the baffles 45 are lowered to a horizontal state, the baffles 45 are correspondingly positioned with respect to the conveying trough 20.

[0059] The baffle 45 is used to form a closed space in the mixing box 3 to block resin vapor. When it is unfolded, its outer contour fits the inner wall of the mixing box 3 and its inner contour fits the outer side of the conveying trough 20. Together with the cover 44 and the unfolded cover 43, it achieves partial space sealing. Together with the exhaust fan 46, it removes resin vapor and prevents resin from condensing on the complex structural components in the upper space.

[0060] When the conveying trough 20 reciprocates to spread the fiber, the baffle 45 is not unfolded and the cover plate 43 below is closed. The resin material is heated and kept in a molten state. After the conveying trough 20 stops shaking and the fiber is spread, the baffle 45 unfolds, the cover plate 43 opens, the first electric telescopic rod 31 extends, pushes the drive roller 33, causing the receiving belt 27 to deform. At the same time, the guide roller 32 guides the receiving belt 27 to move. The spread fiber falls evenly into the resin below the mixing box 3. As the fiber falls, the stirring shaft 36 rotates to dynamically stir the fiber and resin. The exhaust fan 46 is turned on at low speed to remove excess resin vapor. When the material is finished and the mixture is further stirred, the cover plate 43 is closed to prevent the hot resin from evaporating and rising to condense on other components above the mixing box 3.

[0061] In some embodiments, the device is further equipped with a PLC controller, which is electrically connected to the first dispersing component, the second dispersing component, the negative pressure suction fan, the conveying component, the vibrating component, the mixing component, and the extruder, respectively, for centralized control of the start-up, shutdown, and operating parameters of each actuator. The PLC controller can control the start-up sequence of each component according to a preset program, for example, starting the second dispersing component and the negative pressure suction fan first, then starting the first dispersing component and the conveying component, followed by starting the mixing component, and finally starting the extruder, to ensure the continuity and stability of the material conveying and mixing process inside the device.

[0062] In some implementations, the PLC controller is used to adjust the rotational speed of the first and second dispersing components, the vibration frequency of the conveyor, the rotational speed of the mixing component, and the extrusion speed of the extruder, thereby adapting to the processing requirements of different types of fibers and resins.

[0063] In some implementations, the PLC controller can also be connected to a human-machine interface (HMI), through which operators can set, display, and monitor various operating parameters.

[0064] The preform prepared by the device of the present invention is a mixed molding blank formed of fiber and resin, which can be used as a raw material for subsequent molding or curing processes.

[0065] Because this invention performs a two-stage dispersion treatment on the short fibers before they enter the resin, and achieves uniform addition of fibers to the resin through vibration spreading and gentle feeding, the short fibers entering the resin matrix are in a relatively dispersed state. Therefore, from a structural perspective, the preform prepared by the device of this invention exhibits an internal structure in which short fibers are dispersed in the resin matrix as monofilaments or a small number of monofilament bundles, significantly reducing fiber agglomeration; the spatial distribution of fibers in the resin matrix is ​​relatively uniform, making it difficult to form local high fiber enrichment areas; and the fiber surface can be fully coated by the resin, which is beneficial for forming good interfacial bonding during subsequent curing or molding processes.

[0066] Furthermore, since the fibers are already in a relatively uniform spread state before entering the resin, the preform exhibits a relatively uniform appearance and structure after subsequent curing or molding. The fiber content difference in different regions of its cross-section is small, which is beneficial to obtaining composite material products with a relatively uniform distribution of mechanical properties and can reduce the risk of local performance fluctuations caused by uneven fiber distribution.

[0067] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0068] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A fiber composite material extrusion molding preparation apparatus, characterized in that, include: The feeding assembly includes a cavity (1) and a feeding port (2) is provided on one side of the cavity (1); The dispersing component includes a first dispersing component and a second dispersing component. The first dispersing component is disposed at the feed end of the feed inlet (2) and is used to disperse and remove impurities from the short fibers. The second dispersing component is disposed in the cavity (1) and is used to disperse the short fibers by airflow. The mixing assembly includes a mixing box (3), a conveying component, and a mixing component. The mixing box (3) is connected to the cavity (1). A buffer chamber (49) is provided between the cavity (1) and the mixing box (3). The buffer chamber (49) is connected to a negative pressure suction fan (52) and is used to convey the dispersed short fibers from the cavity (1) to the mixing box (3) under negative pressure. The conveying component is provided in the mixing box (3) and is used to uniformly convey the dispersed short fibers. The mixing component is provided in the mixing box (3) and is used to mix the short fibers and resin. The molding assembly includes an extruder (4) and an adjusting component. The extruder (4) is connected to the discharge port (5) at the bottom of the mixing box (3). The adjusting component is located at the output end of the extruder (4). The extruder (4) works in conjunction with the adjusting component to extrude products of different shapes.

2. The fiber composite material extrusion molding preparation apparatus according to claim 1, characterized in that: The first disintegrating component includes a cleaning box (6) connected to the feed inlet (2). A first conveyor belt (7) and a second conveyor belt (8) are installed inside the cleaning box (6). The first conveyor belt (7) and the second conveyor belt (8) form a zigzag conveying path. Two rotating shafts (9) are rotatably connected inside the cleaning box (6). Disintegrating rollers (10) are fixedly connected to the rotating shafts (9). The two disintegrating rollers (10) are located directly above the first conveyor belt (7) and the second conveyor belt (8), respectively. Several steel needles (11) are fixedly connected to the disintegrating rollers (10).

3. The fiber composite material extrusion molding preparation apparatus according to claim 2, characterized in that: Both the first conveyor belt (7) and the second conveyor belt (8) have permanent magnet blocks fixedly connected to their ends.

4. The fiber composite material extrusion molding preparation apparatus according to claim 1, characterized in that: The cavity (1) has an air inlet (13) at the bottom, which is connected to an external fan (14). The second dispersing component includes a gas conveying plate (15) fixedly connected to the bottom of the cavity (1). The gas conveying plate (15) is connected to the air inlet (13). The top of the gas conveying plate (15) has several air outlets (16). An electric heating wire (17) is fixedly connected inside the gas conveying plate (15). A baffle plate (18) is fixedly connected inside the cavity (1). The top of the cavity (1) has several filter ports (19).

5. The fiber composite material extrusion molding preparation apparatus according to claim 1, characterized in that: The conveying component includes a conveying trough (20) with an open structure at both the top and bottom. Two connecting rods (21) are fixedly connected to one end of each end of the conveying trough (20). The other end of the connecting rods (21) extends out of the mixing box (3). A receiving component is provided inside the conveying trough (20) to receive the short fibers after they have been broken up. A vibrating component is provided inside the mixing box (3) to drive the conveying trough (20) to vibrate, so that the received short fibers are laid flat on the receiving component. The receiving component is used to uniformly convey the short fibers into the resin below.

6. The fiber composite material extrusion molding preparation apparatus according to claim 5, characterized in that: The vibrating element is fixedly connected to the support frame (22) on the inner side wall of the mixing box (3). A cam (24) is rotatably connected inside the support frame (22) via a motor (23). The cam (24) is in contact with one end of the conveying groove (20). One end of the connecting rod (21) extends out of the mixing box (3) and is fixedly connected to a limit block (25). A first spring (26) is sleeved on the connecting rod (21). The two ends of the first spring (26) are in contact with the limit block (25) and the support frame (22) respectively.

7. The fiber composite material extrusion molding preparation apparatus according to claim 5, characterized in that: The receiving component includes a receiving belt (27). Slide grooves (28) are provided on opposite sidewalls of the conveying trough (20). A slide rod (34) is fixedly connected within each slide groove (28). A slider (29) is slidably connected to each slide rod (34). A support roller (30) is rotatably connected between two opposing sliders (29). The receiving belt (27) is sleeved on both support rollers (30). A second spring (35) is sleeved at both ends of the slide rod (34). The two ends of the second spring (35) are respectively connected to the receiving belt. The inner wall of the chute (28) and the slider (29) are fixedly connected. The inner wall of the conveying trough (20) is fixedly connected to a first electric telescopic rod (31) and two guide rollers (32). The telescopic end of the first electric telescopic rod (31) is equipped with a drive roller (33). The drive roller (33) is located in the middle of the conveying trough (20) and is in contact with the inner ring wall of the receiving belt (27). The two guide rollers (32) are located on both sides of the drive roller (33) and are in contact with the outer ring wall of the receiving belt (27).

8. The fiber composite material extrusion molding preparation apparatus according to claim 1, characterized in that: The bottom of the mixing box (3) is provided with a heating layer (42) and a heat insulation layer (41). The upper part of the mixing box (3) is provided with a shielding structure to limit the rise of resin vapor. The mixing box (3) is provided with an exhaust port that is connected to the exhaust fan (46).

9. The fiber composite material extrusion molding preparation apparatus according to claim 1, characterized in that: The adjusting component includes a fixed disk (37) which is fixedly connected to the output end of the extruder (4). A connecting port (38) is provided in the middle of the fixed disk (37), and the connecting port (38) is connected to the output end of the extruder (4). Several slides (39) are provided on the fixed disk (37) along the axial direction. Extrusion disks (12) are slidably connected in the slides (39) through threaded rods (40). The extrusion ports on the several extrusion disks (12) are all different in shape.

10. A fiber composite preform, characterized in that, The preform is prepared by an extrusion molding apparatus for fiber composite materials as described in any one of claims 1-9.

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