Method and apparatus for manufacturing continuous fiber-reinforced structural member

Abstract

The present application relates to the technical field of injection molding of structural members, and in particular to a method and apparatus for manufacturing a continuous fiber-reinforced structural member, aiming to solve the problem in the prior art of it being difficult to simultaneously meet the requirements of being lightweight and having high strength in the preparation of structural members. The method comprises: heating a thermoplastic composite material sheet and placing same into a mold; designing an original material formula, preparing materials on the basis of the formula, and mixing the materials into a uniform melt; controlling conveying and injection molding of a melt material by means of a reversing valve; and associating manufacturing data with a product. The apparatus comprises an extrusion mixing mechanism responsible for melting, plasticizing and mixing of the materials in the original material formula, an injection molding mechanism for injecting the melt material, an injection molding machine clamping unit for completing molding and curing, a control system for coordinating the whole process, and an information traceability mechanism for ensuring product traceability. Such a solution is suitable for the manufacture of functional components having extremely high requirements for performance and safety in aerospace and automotive industries.

Description

A method and equipment for manufacturing continuous fiber reinforced structural components

[0001] This application claims priority to Chinese Patent Application No. 202510223800.8, filed on February 27, 2025, entitled "A method and apparatus for manufacturing a continuous fiber reinforced structural component", the entirety of which is incorporated herein by reference. Technical Field

[0002] This application relates to the field of injection molding technology for structural components, and in particular to a method and equipment for manufacturing continuous fiber reinforced structural components. Background Technology

[0003] With the rapid development of the low-altitude economy, it has become an important component of the nation's strategic emerging industries. The low-altitude economy encompasses multiple fields, including low-altitude manufacturing, low-altitude flight, low-altitude support, and integrated services. Low-altitude manufacturing is particularly crucial, encompassing the research and development and production of aircraft and their components. In this field, unprecedentedly stringent requirements have been placed on the lightweighting, stability, and traceability of components, especially for new aircraft such as electric vertical takeoff and landing (eVTOL) aircraft and unmanned flying cars, where the demands for lightweighting, strength, and reliability of components are increasingly significant.

[0004] Structural components of low-altitude aircraft bear the crucial task of supporting and connecting other components. These components must possess sufficient strength and rigidity while also meeting lightweight requirements to improve the overall performance and endurance of the aircraft. While traditional metal materials possess high strength, their weight makes them unsuitable for lightweight applications. Therefore, composite materials and high-performance plastics have gradually become the preferred materials for manufacturing structural components of low-altitude aircraft.

[0005] Compounding injection molding technology is primarily used for formulation design and processing of high-performance, highly filled materials. It uses a twin-screw extrusion compounding system to melt and mix multiple materials to form a homogeneous melt. This melt is then combined with thermoplastic composite sheet processing units and processes, along with injection molding, to produce the desired parts. This technology ensures that materials achieve consistent performance while also being locally reinforced, which is crucial for manufacturing high-performance plastic parts.

[0006] However, existing compound injection molding technology may not be able to fully meet the dual requirements of lightweight and high strength when applied to the manufacture of low-altitude aircraft structural components. This results in compromised product quality during production, limiting its application in the manufacture of high-performance aircraft parts. Furthermore, existing technologies also have shortcomings in areas such as thermal history control during material processing, the introduction and retention of continuous fibers, automation control, and product traceability. Summary of the Invention

[0007] Low-altitude aircraft, such as electric vertical takeoff and landing (eVTOL) aircraft and unmanned flying cars, place extremely high demands on the lightweight, high strength, temperature resistance, corrosion resistance, and impact resistance of structural components. The first aspect of this application provides a method for manufacturing continuous fiber reinforced structural components. The structural components prepared by this method not only effectively balance the requirements for lightweight and high strength but also significantly improve the temperature resistance, corrosion resistance, and impact resistance of the materials, thereby ensuring that the structural components exhibit excellent performance in complex working environments. The method specifically includes the following steps:

[0008] The thermoplastic composite sheet is preheated;

[0009] Design the raw material formula, and feed each component of the raw material formula into the extruder in proportion to obtain the melt material;

[0010] The preheated thermoplastic composite sheet is combined with the melt material by injection molding to obtain a structural component;

[0011] The control system collects the manufacturing data of the structural component and associates the manufacturing data with the structural component;

[0012] The raw material formula includes fibers, which are fed into the extruder by a continuous fiber conveying device. The control system includes a preset proportion of fibers in the raw material formula. The control system interacts with the continuous fiber conveying device to adjust the real-time proportion of fibers so that the real-time proportion of fibers is consistent with the preset proportion.

[0013] Preferably, the fiber enters the extruder at the middle position of the extruder and after the middle position along the material flow direction in the extruder.

[0014] Preferably, the control system interacts with the continuous fiber conveying device to adjust the real-time ratio of the fibers, ensuring that the real-time ratio of the fibers remains consistent with the preset ratio, including:

[0015] The continuous fiber conveying device detects the number of fibers and linear velocity of the fibers and transmits the data to the control system.

[0016] The control system includes the Tex value of the fiber and the real-time delivery rate of each component in the raw material formulation. The control system calculates the fiber mass input into the extruder per unit time according to the following formula:

[0017] The actual fiber mass input into the extruder per unit time = number of fiber strands × linear velocity × Tex value;

[0018] The control system calculates the real-time proportion of the fiber based on the actual fiber mass input into the extruder per unit time and the real-time conveying amount of each component in the raw material formula, and compares it with the preset proportion of the fiber.

[0019] If there is a discrepancy in the comparison results, at least one of the following methods should be used to adjust and eliminate the discrepancy:

[0020] Adjust the fiber count and the extruder screw speed to a minimum of 1 revolution per second.

[0021] Preferably, the preheated thermoplastic composite sheet is combined with the molten material by injection molding to obtain a structural component, including a material storage stage and an injection holding stage.

[0022] The material storage stage includes: conveying the melt material in the extruder to the injection unit; and, if the melt buffer unit contains melt material, also conveying the melt material in the melt buffer unit to the injection unit.

[0023] The injection holding stage includes: injecting the molten material in the injection device into the mold cavity where the thermoplastic composite sheet is located, so that the thermoplastic composite sheet and the molten material are combined to obtain a structural part; at the same time, the extruder is connected to the melt buffer device, and the molten material in the extruder enters the melt buffer device.

[0024] Preferably, during the material storage stage, the temperature in the injection device is 210°C to 400°C, the back pressure is 10 bar to 200 bar, and the maximum material storage position is 5 times the diameter of the injection piston.

[0025] Preferably, during the injection pressure holding stage, the injection speed of the injection device is from 20 mm / s to the upper limit of the injection speed of the injection device, preferably from 20 mm / s to 150 mm / s, the pressure is held at 50 bar to 800 bar during the injection process, and the time is from 0 s to 1000 s, preferably from 2.5 s to 3.5 s;

[0026] Preferably, during the injection holding stage, the temperature of the melt buffer device is 210°C to 400°C;

[0027] Preferably, the material storage stage and the injection and holding stage can be repeated to achieve continuous production of structural components.

[0028] Preferably, the raw material formulation is designed, and the components of the raw material formulation are fed into an extruder in proportion for mixing to obtain a melt material, including:

[0029] The resin matrix, mineral powder and fiber are fed into an extruder in a ratio of (50-60):(1-10):(30-60) to be mixed to obtain a melt material;

[0030] Preferably, the ratio of resin matrix, mineral powder and fiber is 55:5:40;

[0031] Preferably, the resin matrix is ​​made of polypropylene resin;

[0032] Preferably, the fiber is a continuous fiber, and the Tex value of the continuous fiber is set to be between 2300 g / km and 2500 g / km;

[0033] Preferably, the extruder is a twin-screw extruder with an internal temperature of 210°C to 400°C, a yield of 110 kg / h to 120 kg / h, and a screw speed of 180 rpm to 200 rpm.

[0034] Preferably, preheating the thermoplastic composite sheet includes:

[0035] The thermoplastic composite sheet is heated and then placed into a mold at a temperature of 210°C to 230°C.

[0036] Preferably, the thermoplastic composite sheet is made of fiber-reinforced resin material, preferably one of 30% to 60% continuous fiber-reinforced polypropylene resin material, carbon fiber-reinforced polypropylene, and nylon.

[0037] Preferably, collecting the manufacturing data of the structural component and associating it with the structural component includes:

[0038] Collect the manufacturing data of the structural component, encapsulate the received manufacturing data into an information code, and affix the information code to the structural component;

[0039] Preferably, the manufacturing data includes at least one of the following: heating temperature of thermoplastic composite sheet, material mixing parameters, molding parameters, and processor information.

[0040] A second aspect of this application provides a manufacturing apparatus for a continuous fiber reinforced structural member, used to implement the above method. The apparatus includes:

[0041] An extrusion mixing mechanism includes an extruder, a loss-in-weight metering feeder, and a continuous fiber conveying device. The loss-in-weight metering feeder is connected to the extruder and is used to add raw materials and meter the amount of raw materials added. The continuous fiber conveying device is connected to the extruder and is used to convey fibers and collect fiber conveying data in real time and feed it back to the control system.

[0042] Preferably, the fiber enters the extruder at the middle position of the extruder and after the middle position along the material flow direction in the extruder;

[0043] The injection molding mechanism includes an injection unit, a melt buffer unit, a reversing valve, and a lock-up nozzle. The extruder, the injection unit, the melt buffer unit, and the lock-up nozzle are connected through the reversing valve.

[0044] The injection molding machine clamping unit is connected to the injection molding mechanism and is used for molding the structural part;

[0045] A control system, connected to the extrusion mixing mechanism, the injection molding mechanism, and the injection molding machine clamping unit, is used to automate the manufacturing process of the structural component and to collect manufacturing data of the structural component; and

[0046] An information traceability mechanism, connected to the control system, is used to receive manufacturing data collected by the control system and associate the manufacturing data with the structural components.

[0047] Preferably, the continuous fiber conveying device includes a continuous fiber conveying frame, a continuous fiber conveying roller sensor, and a continuous fiber conveying pipe. The fiber inlet ends of the continuous fiber conveying roller sensor and the continuous fiber conveying pipe are both disposed on the continuous fiber conveying frame. Fiber rolls are placed on the continuous fiber conveying frame. The fibers enter the continuous fiber conveying pipe through the continuous fiber conveying roller sensor. The fiber outlet end of the continuous fiber conveying pipe is connected to the extruder.

[0048] Preferably, the injection molding machine clamping unit includes a machine bed, a mold, a robot arm, and a temperature control device. The mold, robot arm, and temperature control device are all mounted on the machine bed, and the mold is connected to the locking nozzle.

[0049] Preferably, the information traceability mechanism includes a data storage unit, an information encapsulation unit, and an information code generation device. The data storage unit is connected to the control system to receive and store the structural component manufacturing data that needs to be associated. The information encapsulation unit is connected to the data storage unit and is used to convert the structural component manufacturing data into information codes suitable for printing or display. The information code generation device is connected to the information encapsulation unit and is used to generate physical QR code labels.

[0050] The above-described solutions of this application have at least the following beneficial effects:

[0051] Firstly, the technical solution of this application utilizes injection molding with continuously fiber-reinforced resin materials, achieving both the mechanical properties and lightweighting goals of low-altitude aircraft structural components. It also enhances the material's temperature resistance, corrosion resistance, and especially its impact resistance. This allows the product to exhibit excellent performance in complex working environments. Furthermore, this application employs a continuous fiber conveying device to feed continuous fibers into a twin-screw extruder. Through interaction between the continuous fiber conveying roller sensor and the control system, the fiber delivery rate can be adjusted in real time to maintain an optimal ratio, further improving the final product quality. In addition, the continuously switching reversing valve and the integrated extruder-injection unit design enable continuous production, reducing production cycles and increasing efficiency. Strict control of key parameters during mixing, injection, and molding processes, such as temperature, pressure, and time, ensures that each step operates at its optimal state, thereby improving molding accuracy and consistency. This method is particularly suitable for manufacturing aerospace or automotive components requiring high mechanical strength, lightweighting, and stable processing characteristics and consistency.

[0052] Secondly, this technical solution integrates a highly efficient extrusion mixing mechanism, a precise injection molding mechanism, a stable injection molding machine clamping unit, and an advanced information traceability system. Continuous glass fiber is added at the downstream opening of the twin-screw extruder, and the fiber processing and dispersion are completed under lower shear forces through a threaded element design, ensuring complete melting and mixing with other material components. This ensures the effective retention of continuous fiber length and improves the overall performance of the composite material. Simultaneously, by using thermoplastic organic sheets, effective localized reinforcement of the product is achieved, meeting the stringent mechanical performance requirements of structural components. This integrated design allows the entire manufacturing process to be completed in one step through injection molding, greatly improving the design freedom and the ability to achieve complex shapes.

[0053] Furthermore, the information traceability mechanism included in this technical solution enhances product transparency and provides strong support for maintenance and quality assurance. The control system collects key data from the manufacturing process in real time, including the heating temperature of the thermoplastic composite sheet, material mixing parameters, molding parameters, etc., and encapsulates this information into information codes (such as QR codes) attached to each finished product. Scanning the information code allows access to detailed production process records, ensuring controllable and traceable product quality. This approach avoids product quality issues and facilitates subsequent tracking and management.

[0054] Furthermore, this equipment can flexibly configure the operating parameters of each component according to specific production requirements to meet the processing needs of different material formulations and diverse product manufacturing needs, especially suitable for low-altitude aircraft structural components requiring high strength and lightweight characteristics. Overall, this technical solution significantly improves production efficiency and product quality, reduces energy consumption and costs, and provides a new solution for the manufacturing of high-performance aircraft components. Attached Figure Description

[0055] The accompanying drawings are provided to further illustrate the present application and form part of the specification. They are used together with the embodiments of the present application to explain the application and do not constitute a limitation thereof. In the drawings:

[0056] Figure 1 is a schematic diagram of the steps of a method for manufacturing a continuous fiber reinforced structural member according to an embodiment of this application;

[0057] Figure 2 is a schematic diagram of the structure of a manufacturing equipment for a continuous fiber reinforced structural member according to an embodiment of this application;

[0058] Figure 3 is a schematic diagram of the extrusion mixing mechanism and injection molding mechanism of the manufacturing equipment for continuous fiber reinforced structural parts according to an embodiment of this application;

[0059] Figure 4 is a schematic diagram of the connection between the extrusion mixing mechanism and the injection molding mechanism of the manufacturing equipment for continuous fiber reinforced structural parts according to an embodiment of this application;

[0060] Figure 5 is a schematic diagram of the connection between the continuous fiber conveying pipe and the extruder of the manufacturing equipment for the continuous fiber reinforced structural member according to an embodiment of this application;

[0061] Figure 6 is a schematic diagram of the continuous fiber conveying device of the manufacturing equipment for continuous fiber reinforced structural parts according to an embodiment of this application;

[0062] Figure 7 is a schematic diagram of the continuous fiber conveying roller sensor of the manufacturing equipment for continuous fiber reinforced structural parts according to an embodiment of this application;

[0063] Figure 8 is a schematic diagram of the report generated by the information traceability mechanism of the manufacturing equipment for continuous fiber reinforced structural parts according to the embodiments of this application when tracing the information of the product.

[0064] Figure label:

[0065] 1. Extrusion mixing mechanism; 11. Extruder; 12. Loss-in-weight metering feeder; 13. Continuous fiber conveying device; 131. Continuous fiber conveying frame; 132. Continuous fiber conveying roller sensor; 133. Continuous fiber conveying pipe;

[0066] 2. Injection molding mechanism; 21. Injection unit; 22. Melt buffer device; 23. Reversing valve; 24. Locking nozzle;

[0067] 3. Injection molding machine clamping unit; 31. Machine bed; 32. Mold; 33. Robot arm; 34. Temperature control device;

[0068] 4. Information traceability agency; 41. Information code generation equipment. Detailed Implementation

[0069] Embodiments of this application will now be described in detail, examples of which are illustrated in the accompanying drawings. The components of the embodiments of this application described and shown in the drawings herein can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application.

[0070] Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0071] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0072] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0073] With the booming development of the low-altitude economy, the research and development and production of new types of aircraft, such as electric vertical takeoff and landing (EVTOL) aircraft and unmanned flying cars, have become crucial. The structural components of these aircraft must not only possess sufficient strength and rigidity to ensure flight safety, but also meet lightweight requirements to improve overall performance and endurance. Traditional metal materials, due to their large weight, are difficult to meet lightweighting demands, while composite materials and high-performance plastics are gradually becoming the preferred choice for manufacturing structural components of low-altitude aircraft. However, existing compound injection molding technology has many shortcomings when applied to the manufacture of low-altitude aircraft structural components. On the one hand, it is difficult to fully balance the dual requirements of lightweighting and high strength, leading to unstable product quality; on the other hand, there are also significant deficiencies in the control of thermal history during material processing, the introduction and retention of continuous fibers, automation control, and product traceability, limiting its application in the manufacture of high-performance aircraft parts. Therefore, developing an injection molding method and equipment that can meet the high-performance requirements of low-altitude aircraft structural components is particularly urgent.

[0074] To address the shortcomings of existing technologies in the manufacturing of structural components for low-altitude aircraft, this application provides a method and equipment for manufacturing continuous fiber reinforced structural components. This aims to solve problems such as the difficulty in balancing lightweight and high strength requirements, imprecise production process control, and poor product traceability in existing technologies. By using continuous fiber reinforced resin materials for injection molding, this application not only effectively improves the mechanical properties of the structural components but also achieves the goal of lightweighting, meeting the high-performance requirements of low-altitude aircraft structural components. Simultaneously, the equipment of this application integrates a highly efficient extrusion mixing mechanism, a precise injection molding mechanism, a stable injection molding machine clamping unit, and an advanced information traceability system. This enables automated control of the production process and real-time acquisition of key data, ensuring product quality stability and traceability. Furthermore, by strictly controlling key parameters such as temperature, pressure, and time during the mixing, injection, and molding processes, this application further improves molding accuracy and product consistency, providing a reliable solution for the efficient and high-quality production of low-altitude aircraft structural components.

[0075] The technical solution of this application will be clearly and completely described below with reference to Figures 1 and 8. Obviously, the described embodiments are only some embodiments of this application, not all embodiments.

[0076] Figure 1 is a schematic diagram of the steps of a method for manufacturing a continuous fiber reinforced structural member according to an embodiment of this application.

[0077] Please refer to Figure 1. The first aspect of this application provides a method for manufacturing a continuous fiber reinforced structural member, comprising the following steps:

[0078] S100. Preheat the thermoplastic composite sheet.

[0079] Before injection molding begins, the thermoplastic composite sheet must first undergo preheating treatment to ensure it meets molding requirements, improve molding results, and enhance the performance of the final product. The specific procedure is as follows:

[0080] After the thermoplastic composite sheet is heated to a certain temperature, it is placed into an injection mold for the subsequent molding steps.

[0081] In some specific examples, the heating process can be carried out using an infrared heating station, a heating furnace, or other temperature control devices.

[0082] In some specific examples, the temperature of the heated thermoplastic composite sheet ranges from 180°C to 400°C, for example, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 300°C, 350°C, and 400°C. This preheating treatment allows the thermoplastic composite sheet to better integrate with the subsequently injected molten material during the injection molding process, thereby improving the bonding strength of the final product.

[0083] In some specific examples, the thermoplastic composite sheet material can be any fiber-reinforced resin, such as continuous fiber-reinforced polypropylene resin, carbon fiber-reinforced polypropylene, nylon, etc., preferably 30% to 60% continuous fiber-reinforced polypropylene resin, such as 30%, 40%, 45%, 50%, 60%, etc., preferably 45%. This material has excellent mechanical properties, improved temperature resistance and impact resistance, and is suitable for manufacturing high-performance components such as low-altitude aircraft.

[0084] S200. Design the raw material formula, and feed each component in the raw material formula into the extruder in proportion to obtain the melt material.

[0085] In this step, raw materials of different compositions are fed into an extruder for mixing and melting to prepare a melt material, ensuring that the final structural component possesses the required properties during the molding process. This step specifically includes:

[0086] Designing the raw material formula involves preparing the raw materials according to a certain ratio of resin matrix, mineral powder, and fiber. The specific ratio can be adjusted according to different products. A preferred ratio of resin matrix, mineral powder, and fiber is (50-60):(1-10):(30-60), for example, (50, 52, 54, 56, 58, 60):(1, 2, 4, 6, 8, 10):(30, 32, 35, 37, 39, 41, 43, 45, 50, 55, 60). Preferably, the raw materials are prepared according to a ratio of 55% resin matrix, 5% mineral powder, and 40% continuous fiber. The resin matrix and mineral powder are stored separately in individual hoppers. The addition of mineral powder can improve the rigidity and wear resistance of the material; the addition of continuous fiber improves the tensile strength, rigidity, fatigue resistance, and impact resistance of the structural components.

[0087] The resin matrix and mineral powder are accurately fed into the extruder for mixing via a loss-in-weight metering feeder. Simultaneously, continuous fiber is fed into the extruder via a continuous fiber conveying device, ensuring thorough mixing of the continuous fiber with the resin matrix and mineral powder. The input amount of continuous fiber can be calculated in real time, and the proportion of continuous fiber to the material can be maintained within a set range by fine-tuning the extruder screw speed or adjusting the fiber quantity.

[0088] The fiber inlet is located at or after the middle of the extruder along the material flow direction. Strong shearing forces are generated at the front screw of the extruder, which can easily lead to excessive shearing and damage to the fibers. Positioning the fiber inlet at or after the middle position avoids subjecting the fibers to high-intensity shearing forces upon entry into the extruder, thus maintaining fiber integrity and length. This, in turn, improves the mechanical properties of the composite material, such as tensile strength, rigidity, and fatigue resistance.

[0089] In some specific examples, continuous fibers can be made of continuous glass fiber, continuous carbon fiber, continuous aramid fiber, etc.

[0090] Finally, the extruder processes the raw materials to obtain a uniform melt, which then proceeds to the next molding process.

[0091] In this step, the final product is molded directly using a specially designed formula, eliminating the need for sourcing commercially available plastic particles. This not only simplifies the production process but also effectively reduces manufacturing costs. The introduction of continuous fibers significantly increases the effective fiber retention length within the resin matrix. Compared to using chopped fibers, continuous fibers form a more complete network structure and skeletal support within the resin matrix, thereby greatly improving the energy absorption capacity of the reinforcing material and significantly enhancing its overall strength. This step ensures that the final structural component exhibits superior mechanical properties and higher reliability under external forces.

[0092] In some specific examples, the resin matrix is ​​usually made of polypropylene resin, which has good corrosion resistance, thermal stability and molding properties.

[0093] In some specific examples, continuous fibers with a Tex value of 1200 g / km to 2500 g / km are selected, such as 1200 g / km, 1500 g / km, 1800 g / km, 2000 g / km, 2100 g / km, 2200 g / km, 2300 g / km, 2400 g / km, and 2500 g / km, with 1200 g / km or 2400 g / km being preferred. "Tex value" is a unit used in the textile industry to express the fineness of yarn or fiber, defined as the weight in grams of fiber per 1000 meters. Using continuous fibers with higher Tex values ​​can help achieve better mechanical properties while reducing the risk of fiber breakage, thereby ensuring the quality and reliability of the finished product.

[0094] In some specific examples, the extruder can be a twin-screw extruder. The twin-screw extrusion compounding system is responsible for the efficient melt mixing and dispersion of raw materials (such as resin matrix, mineral powder, and continuous fibers), ensuring uniform distribution of each component. During this process, the melt is directly fed into the piston of the subsequent injection unit. Compared to traditional injection molding methods using commercial plastic particles, this approach significantly reduces the thermal history of material processing. By reducing the number of heat treatments, the performance degradation of the material during processing is effectively reduced, preserving the original properties of the material.

[0095] In some specific examples, the temperature of the twin-screw extruder is set to 210°C to 400°C, for example, 210°C, 220°C, 250°C, 280°C, 300°C, 320°C, 340°C, 380°C, 400°C, etc., preferably 240°C, to ensure that the resin matrix, mineral powder and continuous fibers can be fully melted and uniformly mixed during the extrusion process.

[0096] In some specific examples, the yield of the twin-screw extruder is set to 110 kg / h to 120 kg / h, such as 110 kg / h, 111 kg / h, 112 kg / h, 113 kg / h, 114 kg / h, 115 kg / h, 116 kg / h, 117 kg / h, 118 kg / h, 119 kg / h, 120 kg / h, etc., preferably 114 kg / h, and the screw speed is set to 180 rpm to 200 rpm, such as 180 rpm, 185 rpm, 188 rpm, 189 rpm, 190 rpm, 195 rpm, 200 rpm, etc., preferably 189 rpm, to meet the needs of large-scale production and maintain a stable mixing effect.

[0097] S300: Preheated thermoplastic composite sheet and molten material are combined by injection molding to obtain structural parts.

[0098] The molten material is fed into an injection mold containing a preheated thermoplastic composite sheet for molding, producing the target structural part. This step includes the following specific operations:

[0099] S310. Adjust the reversing valve to the first state to enter the material storage stage.

[0100] The storage stage involves transporting the molten material from the extruder to the injection unit. If the melt buffer unit contains molten material, the molten material in the melt buffer unit is also transported to the injection unit.

[0101] In its first state, the reversing valve allows the extruder and melt buffer device to be connected to the injection unit, but not to the injection mold.

[0102] In some specific examples, the extruder employs a twin-screw extruder, which can efficiently and completely melt and uniformly mix the molten material, thus allowing a piston to replace the screw used for plasticizing in the injection unit. This design not only simplifies the structure of the injection unit and reduces unnecessary parts, but also significantly increases its effective utilization rate compared to traditional screw-type injection units. Furthermore, it significantly reduces the effects of the melt being subjected to screw shearing, thereby avoiding loss of material properties. Most importantly, it effectively protects the retained length of continuous fibers, preventing them from being shortened by additional shear forces, thus ensuring the mechanical strength of the composite material.

[0103] In some specific examples, the temperature inside the injection device is set to 210°C to 400°C, for example, 210°C, 220°C, 250°C, 280°C, 300°C, 320°C, 340°C, 380°C, 400°C, etc., preferably 245°C. This temperature can ensure the fluidity of the melt material during the injection process.

[0104] In some specific examples, the back pressure of the injection device is set to 10 bar to 200 bar, for example, 10 bar, 20 bar, 30 bar, 40 bar, 50 bar, 100 bar, 150 bar, 200 bar, etc., preferably 45 bar. The back pressure is the backward pressure borne by the piston or screw inside the injection device. The function of the back pressure is to ensure that the melt can be fully compacted, remove air bubbles, increase the melt density, and ensure uniform mixing of materials.

[0105] In some specific examples, the material storage position of the injection device is set to 5 times the diameter of the injection piston. The preferred material storage position is 250mm to 300mm, such as 250mm, 260mm, 270mm, 280mm, 290mm, 300mm, etc., and more preferably 280mm. This is the position setting of the piston or screw in the injection device, that is, during the material storage stage, the piston or screw in the injection device retracts to a distance of 250mm to 300mm from the injection end of the injection device.

[0106] In some specific examples, if injection holding has been performed before this stage, then this stage is performed simultaneously with the cooling stage in the mold.

[0107] S320, Adjust the reversing valve to the second state to enter the injection pressure holding stage.

[0108] During the injection holding stage, the injection device is connected to the lock-up nozzle, allowing the molten material to be injected from the injection device into the injection mold and bonded to the thermoplastic composite sheet through injection molding, followed by holding pressure. At the same time, the injection device is disconnected from the extruder and the melt buffer device, while the extruder is connected to the melt buffer device. The molten material in the extruder enters the melt buffer device, and the piston of the melt buffer moves upward to prepare for the injection stage.

[0109] In some specific examples, the injection unit injects molten material into the injection mold containing the preheated thermoplastic composite sheet at a speed of 20 mm / s to 150 mm / s through a lock-type nozzle. For example, the injection speed can be 20 mm / s, 30 mm / s, 50 mm / s, 80 mm / s, 100 mm / s, 120 mm / s, 150 mm / s, etc., with a preferred injection speed of 65 mm / s. This operation ensures that the molten material can quickly and uniformly fill the entire mold cavity and bond tightly with the preheated thermoplastic composite sheet. The selection of the injection speed is crucial to ensuring that the melt can quickly and uniformly fill the entire mold cavity. If the injection speed is too slow, the melt may cool too quickly and fail to completely fill the mold cavity; if it is too fast, excessive shear heat may be generated or gas in the mold cavity may not be able to escape in time, forming defects such as bubbles or shrinkage cavities.

[0110] In some specific examples, a holding pressure procedure is performed simultaneously during the molten material injection process. The holding pressure can be adjusted according to the actual product being produced, ranging from 50 to over 1000 bar. The holding time can also be adjusted according to the actual product, ranging from 0 to over 1000 seconds, preferably from 50 to 800 bar, such as 50 bar, 100 bar, 150 bar, 200 bar, 300 bar, 400 bar, 500 bar, 600 bar, 700 bar, 800 bar, etc., and more preferably from 280 to 320 bar. The injection time can be determined according to product requirements, ranging from 0 to 1000 seconds, such as 1 second, 100 seconds, 500 seconds, 1000 seconds, etc., preferably from 2.5 to 3.5 seconds, such as 2.5 seconds, 2.6 seconds, 2.7 seconds, 2.8 seconds, 2.9 seconds, 3.0 seconds, 3.1 seconds, 3.2 seconds, 3.3 seconds, 3.4 seconds, 3.5 seconds, etc. When producing medium to large-sized products, a pressure of 500 bar can be maintained for 5 seconds to inject the molten material. The main purpose of holding pressure is to ensure the density and smoothness of the melt within the mold cavity, preventing product defects caused by cooling shrinkage. Appropriate holding pressure can improve the quality and dimensional accuracy of the finished product, especially important for large or complex-shaped parts.

[0111] In some specific examples, the melt buffer is maintained at 210°C to 400°C throughout the process, for example, 210°C, 220°C, 250°C, 280°C, 300°C, 320°C, 340°C, 380°C, 400°C, etc., preferably 240°C. The temperature of the melt buffer is close to or the same as the extruder temperature, ensuring that the melt material does not solidify due to temperature drop during the buffering period. Simultaneously, it receives fresh melt material from the extruder, preparing it for the next injection.

[0112] The control valve alternates between the first and second states, repeatedly performing material storage and injection pressure holding, thus achieving continuous and efficient fabrication of structural components. This dynamic switching mechanism ensures that a series of operations, including molten material delivery, injection, pressure holding, and cooling, can be completed accurately and without error in each cycle.

[0113] This continuous production model not only improves production efficiency but also reduces equipment downtime, energy consumption, and costs.

[0114] The above steps realize the integrated operation of material formulation melting and mixing and injection, which greatly shortens the thermal process of material processing and maintains the original properties of the material to the greatest extent. This not only improves production efficiency, but also ensures the stability and reliability of product quality.

[0115] S400: Collect manufacturing data of structural components and associate it with the structural components.

[0116] To ensure product quality and facilitate traceability, an information management system is used to monitor the production process and link relevant data with structural components. The specific operations are as follows:

[0117] The control system collects key data in real time during the manufacturing process, including the heating temperature of thermoplastic composite sheets, material mixing parameters, molding parameters, and processor information. The collected data is transmitted to an information traceability agency, which encapsulates the data and generates information codes (such as QR codes).

[0118] Information codes are affixed or printed on each structural component as a unique identifier for the product. These codes allow for tracing the product's production batch, manufacturing process, and relevant parameters, thus ensuring product quality control and traceability.

[0119] The manufacturing method for continuous fiber reinforced structural components provided in the above embodiments of this application, through injection molding of continuously fiber reinforced resin materials, not only improves the mechanical properties of low-altitude aircraft structural components but also increases the material's high-temperature resistance, corrosion resistance, and impact resistance, exhibiting excellent performance in complex working environments. By employing a continuously switching reversing valve and an integrated extruder-injection unit design, this method enables continuous production, reduces production cycles, and improves production efficiency. Through strict manufacturing process control and real-time data acquisition, this method ensures that each production batch meets quality standards and has high traceability, avoiding product quality issues. Precise control of key parameters in the mixing, injection, and molding processes, such as temperature, pressure, and time, ensures that each step is in optimal working condition, thereby improving molding accuracy and consistency.

[0120] In manufacturing structural components for low-altitude aircraft, the method for manufacturing continuous fiber reinforced structural components provided in the above embodiments of this application not only improves the overall performance of the material by combining a twin-screw extrusion compounding system with an injection molding system, but also achieves effective local reinforcement of the product by using thermoplastic organic sheets. This method can provide additional strength support in critical areas, thereby meeting the stringent mechanical performance requirements of the structural components. Furthermore, this integrated design allows the entire manufacturing process to be completed in one step through injection molding, greatly improving the design freedom and the ability to achieve complex shapes. This is currently an effective means of manufacturing plastic parts that require both extreme lightweight performance and high mechanical strength. For example, in manufacturing the cabin roof shell of an electric vertical takeoff and landing (eVTOL) aircraft, this method ensures that the 45% continuous fiber reinforced polypropylene resin material used maintains optimal performance during the molding process, thereby providing the required high strength and lightweight characteristics.

[0121] This method is particularly suitable for applications requiring high strength, high temperature resistance, and good toughness, such as those in the aerospace or automotive industries. It ensures that continuous fibers and other additives are uniformly distributed throughout the product, resulting in excellent mechanical properties and reliability.

[0122] The manufacturing equipment for continuous fiber reinforced structural members provided in this application will be described in detail below with reference to Figures 2 to 7. It should be understood that this equipment is used to implement the steps in the above method embodiments, that is, the descriptions of the equipment embodiments and the method embodiments correspond to each other, and therefore, the parts of the two types of embodiments that are not described in detail can be referred to each other.

[0123] Figure 2 is a structural schematic diagram of a manufacturing equipment for a continuous fiber reinforced structural member according to an embodiment of this application; Figure 3 is a structural schematic diagram of the extrusion mixing mechanism and the injection molding mechanism of the manufacturing equipment for a continuous fiber reinforced structural member according to an embodiment of this application; Figure 4 is a structural schematic diagram of the connection between the extrusion mixing mechanism and the injection molding mechanism of the manufacturing equipment for a continuous fiber reinforced structural member according to an embodiment of this application; Figure 5 is a structural schematic diagram of the connection between the continuous fiber conveying pipe and the extruder of the manufacturing equipment for a continuous fiber reinforced structural member according to an embodiment of this application; Figure 6 is a structural schematic diagram of the continuous fiber conveying device of the manufacturing equipment for a continuous fiber reinforced structural member according to an embodiment of this application; Figure 7 is a structural schematic diagram of the continuous fiber conveying roller sensor of the manufacturing equipment for a continuous fiber reinforced structural member according to an embodiment of this application.

[0124] Referring to Figures 2 to 7, the second aspect of this application provides a manufacturing equipment for continuous fiber reinforced structural parts. This equipment integrates extrusion mixing, injection molding, molding, and information traceability functions, aiming to achieve efficient and high-quality production of composite material structural parts. Specifically, it includes: an extrusion mixing mechanism 1, an injection molding mechanism 2, an injection molding machine clamping unit 3, a control system, and an information traceability mechanism 4.

[0125] The extrusion mixing mechanism 1 includes an extruder 11, a loss-in-weight metering feeder 12, and a continuous fiber conveying device 13. The loss-in-weight metering feeder 12 is connected to the extruder 11 and is used to add raw materials and meter the amount of raw materials added. The continuous fiber conveying device 13 is connected to the extruder 11 and is used to input and meter continuous fibers. The fiber inlet position in the extruder is located at or after the middle position of the extruder along the material flow direction. Preferably, the fiber inlet position in the extruder is between 1 / 2 and 1 / 3 of the length of the extruder along the material flow direction.

[0126] The extruder 11 is responsible for melting and mixing raw materials (such as polypropylene resin matrix and mineral powder) with continuous fibers to form a uniform melt material.

[0127] In some specific examples, extruder 11 uses a twin-screw extruder, with continuous glass fiber added at the downstream opening of the twin-screw extruder. The fiber is processed and dispersed under lower shear force through the design of the screw element, and is completely melted and mixed with other material components, ensuring that the continuous fiber effectively retains its length and improving the overall performance of the composite material.

[0128] The loss-in-weight metering feeder 12 is installed on the extruder 11 and is used to accurately add and meter the amount of raw materials. For example, in one specific embodiment, after designing the raw material formula, the loss-in-weight metering feeder 12 can set the input amount of each component according to the proportion of each component in the raw material formula, thereby feeding each component in the raw material formula into the extruder for mixing in proportion. This setting can ensure that the formula ratio is accurate and avoid product defects caused by inaccurate raw material ratio or uneven dispersion.

[0129] The continuous fiber conveying device 13 is also connected to the extruder 11 and is responsible for inputting and metering the continuous fibers. This device, in conjunction with the control system and the extruder, can achieve closed-loop control of the continuous fiber input amount, that is, automatically adjust the continuous fiber input rate according to the set parameters to ensure the uniform distribution of continuous fibers in the melt. For example, for 40% continuous fibers, its input speed can be monitored in real time by a sensor and kept stable by the closed-loop control system.

[0130] The injection mechanism 2 includes an injection unit 21, a melt buffer unit 22, a reversing valve 23, and a lock-up nozzle 24. The melt buffer unit 22 and the injection unit 21 are interconnected through the reversing valve 23.

[0131] The injection unit 21 receives molten material from the extruder 11 and the melt buffer unit 22 and injects it into the mold of the injection molding machine clamping unit 3 at a specific speed and pressure. The injection unit 21 is equipped with a precision control unit that can adjust the injection speed (e.g., 65 mm / s) and holding pressure (e.g., 300 bar, 3 seconds) to ensure the quality and repeatability of the melt filling the mold cavity.

[0132] The melt buffer device 22 is located between the extruder 11 and the injection device 21. It is used to receive the melt material in the extruder 11 during the injection holding stage and to transport the material inside the extruder to the injection device 21 during the storage stage. In other words, it plays a role in balancing the continuous operation of the extruder and the intermittent injection operation rhythm of the injection device, reducing fluctuations caused by asynchrony, and enabling the extruder 11 and the injection device 21 to work together.

[0133] As a key component connecting the extruder 11, the injection unit 21 and the lock-up nozzle 24, the reversing valve 23 can switch between the first state and the second state, realizing the storage and injection transfer of melt material.

[0134] In the first state, which is the material storage stage, the extruder 11 and the melt buffer device 22 are connected to the injection device 21 by adjusting the reversing valve 23. However, the injection device 21 cannot be connected to the mold of the injection molding machine clamping unit 3 through the locking nozzle 24.

[0135] In the second state, namely the injection holding stage, the extruder 11 is connected to the melt buffer device 22 by adjusting the reversing valve 23, but not to the injection device 21; and the injection device 21 is connected to the mold of the injection molding machine clamping unit 3 through the locking nozzle.

[0136] The lock-up nozzle 24 is installed at the front end of the injection unit 21 and directly contacts the mold 32. It is responsible for introducing the molten material into the mold cavity of the mold clamping unit 3 of the injection molding machine for injection molding of structural parts. The design of the lock-up nozzle 24 needs to consider factors such as sealing performance, high temperature resistance, and ease of cleaning to ensure stable operation over a long period of time.

[0137] The injection molding machine clamping unit 3 is connected to the injection molding mechanism 2 and is used for molding structural parts.

[0138] The control system (not shown in the figure) is electrically connected to the extrusion mixing mechanism 1, the injection molding mechanism 2, and the injection molding machine clamping unit 3, respectively, realizing a high degree of automation of the entire manufacturing process. It not only monitors the working status of each component, but also automatically adjusts some parameters according to preset programs to ensure that each step is executed under optimal conditions.

[0139] The control system is responsible for collecting key manufacturing data, such as the heating temperature of thermoplastic composite sheet, material mixing parameters, molding conditions, etc., and transmitting this information to the information traceability agency 4 for subsequent product quality tracking and management.

[0140] As shown in Figure 8, the information traceability mechanism 4 is connected to the control system, receiving and processing manufacturing data, and then encapsulating it into an information code. Each finished product is accompanied by a unique information code, which, when scanned, allows access to detailed production process records, including but not limited to organic sheet heating information, injection molding parameters, and processor information. This approach not only enhances product transparency but also provides strong support for maintenance and quality assurance.

[0141] In some embodiments, referring to Figures 3 and 6, the continuous fiber conveying device 13 includes a continuous fiber conveying frame 131, a continuous fiber conveying roller sensor 132, and a continuous fiber conveying pipe 133. The fiber inlet ends of the continuous fiber conveying roller sensor 132 and the continuous fiber conveying pipe 133 are disposed on the continuous fiber conveying frame 131. A continuous fiber roll is placed on the continuous fiber conveying frame 131. The continuous fiber passes through the continuous fiber conveying roller sensor 132, enters the continuous fiber conveying pipe 133, and enters the middle or rear section of the twin-screw extruder through the fiber outlet end of the continuous fiber conveying pipe 133, thereby avoiding the plasticizing section of the front section of the twin-screw extruder and threaded structures such as kneading blocks or mixing blocks. This can prevent the continuous fiber from being excessively crushed.

[0142] The continuous fiber conveying roller sensor 132 monitors the quantity, linear velocity (km / h), and tension of continuous fibers passing through the conveying pipe in real time, providing accurate data feedback to the control system. The control system is pre-set with the required percentage of continuous aramid fiber mass to the total material per unit time, i.e., the preset ratio of continuous fibers, and the Tex value of the continuous fibers (e.g., 2400 g / km). Then, based on the formula: Fiber mass input into the twin-screw extruder per unit time = Fiber bundle strands × Fiber input linear velocity × Tex value, the control system can calculate the real-time continuous fiber input into the twin-screw extruder per unit time. Simultaneously, the control system can monitor the real-time conveying volume of each component in the raw material formula per unit time, and then divide the real-time input fiber mass by the real-time total material conveying volume to obtain the real-time continuous fiber conveying ratio, comparing it with the preset ratio. If a deviation exists, the continuous fiber mass input into the twin-screw extruder per unit time will be controlled by fine-tuning the twin-screw extruder screw speed (minimum screw speed change is 1 revolution per second) or increasing / decreasing the continuous fiber quantity, ensuring it remains as consistent as possible with the set percentage value.

[0143] In some specific examples, the control system also includes information such as the current equipment output (in kilograms per hour).

[0144] The fiber output end of the continuous fiber conveying pipe 133 is connected to the middle and rear section of the extruder 11, forming a closed continuous fiber transmission channel. This ensures that the continuous fiber is not affected by the external environment during the process from the conveyor to the extruder, avoiding interference from pollutants such as dust and moisture, and also preventing the continuous fiber from knotting or tangling.

[0145] In this embodiment, the three components together form a closed-loop control system (this closed-loop control function can be selectively activated or deactivated) to ensure the precise input of continuous fibers. By optimizing the design and arrangement of each component, the entire conveying system can operate efficiently with minimal shear force, maximizing the preservation of the original length of the continuous fibers, which is particularly important for enhancing the mechanical properties of composite materials. Precise continuous fiber metering and a stable conveying process not only improve product quality but also reduce the scrap rate caused by uneven continuous fiber input, thereby improving overall production efficiency and consistency.

[0146] In some specific examples, the number of continuous fibers should be around 8 strands. If the number of fibers (strands) is too small or too large when the required continuous fiber feed amount is fixed, the continuous fiber linear speed needs to be increased or decreased, that is, the screw speed needs to be increased or decreased significantly. If the screw speed is changed significantly, other problems will arise. Therefore, by controlling the number of continuous fiber strands to around 8 strands, the continuous fiber feed amount can be controlled more precisely, thereby producing better quality structural components.

[0147] In some specific examples, the number of continuous fibers is 8 strands, the continuous fiber conveying roller sensor 132 measures the continuous fiber linear speed as 2.38 km / h, and the Tex value of the continuous fiber is 2400 g / km. At this time, the fiber mass input into the twin-screw extruder per unit time = fiber quantity × fiber input linear speed × Tex value = 8 × 2.38 km / h × 2400 g / km = 45700 g / h = 45.7 kg / h. The control system will compare this value with the preset required value. At this time, the screw speed of the twin-screw extruder is 195 rpm. If there is a deviation in the comparison, the control center will further fine-tune the screw speed of the twin-screw extruder to make it as close as possible to the set value.

[0148] In some embodiments, referring to FIG2, the injection molding machine clamping unit 3 includes a machine bed 31, a mold 32, a robot arm 33, a temperature control device 34, a fixed mold plate, a moving mold plate, etc.

[0149] The machine bed 31 serves as a support platform, supporting the mold 32, the robot arm 33, and the temperature control device 34, and providing a stable installation foundation.

[0150] The mold 32 is mounted on the machine bed 31 and directly connected to the locking nozzle 24. It carries the preheated thermoplastic composite sheet and receives molten material from the injection molding mechanism. The mold is a key component that determines the shape and size of the final product. It has precision chambers and channels inside, which can accurately control the flow path of the melt and ensure that every detail meets the design requirements.

[0151] Mold 32 is typically made of high-strength alloy steel, possessing excellent thermal conductivity and wear resistance. To improve production efficiency, the mold is also equipped with a quick-change interface for easy switching between different batches. Furthermore, a heating element is integrated inside the mold.

[0152] The robotic arm 33 can be mounted on the machine bed 31, near the mold, according to actual production needs. The robotic arm 33 is responsible for automated operations, including placing the cut sheets into the infrared heating station for preheating, hanging the preheated sheets into the mold 32, and removing the finished product. The design of the robotic arm needs to consider flexibility, accuracy, and speed to ensure that each action is executed precisely.

[0153] The temperature control device 34 can be installed on the machine bed 31 or on the fixed template, arranged around the mold 32, according to actual production needs. The temperature control device 34 can preheat the thermoplastic composite sheet as needed, promote good bonding between the melt and the thermoplastic composite sheet, and avoid product defects caused by temperature difference.

[0154] In some specific examples, the temperature control device 34 is usually in the form of an infrared heating station, an electric heating plate or an induction heater, which has the characteristics of rapid heating, uniform heating and easy control.

[0155] In some embodiments, the information traceability mechanism 4 includes a data storage unit (not shown in the figure), an information encapsulation unit (not shown in the figure), and an information code generation device 41. The data storage unit is connected to the control system to receive and store the structural component manufacturing data that needs to be associated. The information encapsulation unit is connected to the data storage unit and is used to convert the structural component manufacturing data into an information code suitable for printing or display. The information code generation device 41 is connected to the information encapsulation unit and is used to generate a physical QR code label as shown in Figure 8.

[0156] The workflow of the injection molding equipment for manufacturing structural components of low-altitude aircraft provided in the second aspect of this application is as follows:

[0157] (1) Preheat-treated thermoplastic composite sheet:

[0158] The thermoplastic composite sheet is preheated by temperature control device 34, and then placed into mold 32 by robot arm 33 in preparation for subsequent molding steps.

[0159] (2) Material mixing:

[0160] The resin matrix and mineral powder are fed into the extruder 11 in proportion by the loss-in-weight metering feeder 12; at the same time, the continuous fiber is fed into the extruder 11 in proportion by the continuous fiber conveying device 13.

[0161] The extruder 11 melts and mixes the above components at a certain temperature and speed to obtain a uniform melt material.

[0162] (3) Storage and injection of melt materials:

[0163] Adjust the reversing valve 23 to the first state to transport the molten material in the extruder 11 to the injection unit 21.

[0164] After the material storage is completed, the reversing valve 23 is adjusted to the second state, so that the injection device 21 injects the molten material into the mold 32 containing the preheated thermoplastic composite material sheet at a certain injection speed through the locking nozzle 24, and holds the pressure to ensure that the molten material is tightly bonded to the thermoplastic composite material sheet and fills the entire mold cavity.

[0165] During this process, the melt buffer device 22 maintains the same temperature as the injection device 21 (this temperature is set to be the same during the initial setup) and receives fresh melt material from the extruder to prepare for the next storage stage.

[0166] After injection, the reversing valve 23 is adjusted back to the first state to transport the melt material in the extruder 11 and melt buffer device 22 to the injection device 21. Then the reversing valve is switched again to continuously prepare the structural parts in a cyclical manner.

[0167] (4) Structural component forming:

[0168] After injection, during the material storage stage, the molten material cools and solidifies in the mold 32 to form the final structural component. After the mold is opened, it is removed by the robot arm 33, and then a new preheated thermoplastic composite sheet is placed in it to wait for the next injection.

[0169] (5) Data collection and information traceability:

[0170] The control system collects key data throughout the manufacturing process, such as the heating temperature of thermoplastic composite sheets, material mixing parameters, and molding parameters.

[0171] These data are transmitted to the information traceability agency 4, which encapsulates the data into an information code (such as a QR code) as shown in Figure 8, and attaches the information code to each finished product to achieve product traceability.

[0172] The second aspect of this application provides a manufacturing equipment for continuous fiber-reinforced structural components. By rapidly alternating between a first and second state using a reversing valve, continuous and efficient fabrication of structural components is achieved, reducing equipment downtime and significantly improving overall work efficiency. The collaborative operation of a robotic arm and an intelligent control system automates the entire process from preheating of thermoplastic composite sheet to finished product removal, reducing manual intervention, minimizing human error, and improving production stability.

[0173] This equipment enables strict control over key process parameters such as injection speed, holding pressure, and melt buffer temperature, ensuring that each production step is executed under optimal conditions, thereby significantly improving the quality of the finished product. Furthermore, the use of a twin-screw extruder for material mixing reduces the risk of the melt being subjected to further shearing, protecting the length of continuous fibers and improving the mechanical strength and durability of the composite material. The equipment collects and transmits manufacturing data through a control system, and an information traceability mechanism generates a QR code containing detailed manufacturing information, which is affixed or printed on each finished product. This approach not only enhances product transparency but also provides strong support for maintenance and quality assurance, facilitating later tracking and management.

[0174] In addition, the equipment can flexibly configure the working parameters of each component according to specific production requirements to meet diverse product manufacturing needs, and is particularly suitable for low-altitude aircraft structural components that require high strength and lightweight characteristics.

[0175] It should be noted that the technical solutions in the various embodiments of this application can be combined with each other, but the basis for such combination is that they can be implemented by those skilled in the art. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist, that is, it is not within the protection scope of this application.

[0176] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for manufacturing a continuous fiber reinforced structural component, characterized in that, Includes the following steps: The thermoplastic composite sheet is preheated; Design the raw material formula, and feed each component of the raw material formula into the extruder in proportion to obtain the melt material; The preheated thermoplastic composite sheet is combined with the melt material by injection molding to obtain a structural component; The control system collects the manufacturing data of the structural component and associates the manufacturing data with the structural component; The raw material formula includes fibers, which are fed into the extruder by a continuous fiber conveying device. The control system includes a preset proportion of fibers in the raw material formula. The control system interacts with the continuous fiber conveying device to adjust the real-time proportion of fibers so that the real-time proportion of fibers is consistent with the preset proportion.

2. The method for manufacturing a continuous fiber reinforced structural member according to claim 1, characterized in that, The fiber enters the extruder at the middle position and after the middle position along the material flow direction in the extruder.

3. The method for manufacturing a continuous fiber reinforced structural member according to claim 1, characterized in that, The control system interacts with the continuous fiber conveying device to adjust the real-time ratio of the fibers, ensuring that the real-time ratio of the fibers remains consistent with the preset ratio, including: The continuous fiber conveying device detects the number of fibers and linear velocity of the fibers and transmits the data to the control system. The control system includes the Tex value of the fiber and the real-time delivery rate of each component in the raw material formula. The control system calculates the mass of fibers input into the extruder per unit time according to the following formula: The actual fiber mass input into the extruder per unit time = number of fiber strands × linear velocity × Tex value; The control system calculates the real-time proportion of the fiber based on the actual fiber mass input into the extruder per unit time and the real-time conveying amount of each component in the raw material formula, and compares it with the preset proportion of the fiber. If there is a discrepancy in the comparison results, at least one of the following methods should be used to adjust and eliminate the discrepancy: Adjust the fiber count and the extruder screw speed to a minimum of 1 revolution per second.

4. The method for manufacturing a continuous fiber reinforced structural member according to claim 1, characterized in that, The preheated thermoplastic composite sheet is combined with the molten material by injection molding to obtain a structural component, including a material storage stage and an injection holding stage. The material storage stage includes: conveying the melt material in the extruder to the injection unit; and, if the melt buffer unit contains melt material, also conveying the melt material in the melt buffer unit to the injection unit. The injection holding stage includes: injecting the molten material in the injection device into the mold cavity where the thermoplastic composite sheet is located, so that the thermoplastic composite sheet and the molten material are combined to obtain a structural part; at the same time, the extruder is connected to the melt buffer device, and the molten material in the extruder enters the melt buffer device.

5. The method for manufacturing a continuous fiber reinforced structural member according to claim 4, characterized in that, During the material storage stage, the temperature in the injection device is 210°C to 400°C, the back pressure is 10 bar to 200 bar, and the maximum material storage position is 5 times the diameter of the injection piston.

6. The method for manufacturing a continuous fiber reinforced structural member according to claim 4, characterized in that, During the injection and pressure holding phase, the injection speed of the injection device is from 20 mm / s to the upper limit of the injection speed of the injection device, and the pressure is held from 50 bar to 800 bar during the injection process for 0 s to 1000 s.

7. The method for manufacturing a continuous fiber reinforced structural member according to claim 4, characterized in that, The injection speed of the injection device is from 20 mm / s to 150 mm / s.

8. The method for manufacturing a continuous fiber reinforced structural member according to claim 4, characterized in that, The injection process takes 2.5 to 3.5 seconds.

9. The method for manufacturing a continuous fiber reinforced structural member according to claim 4, characterized in that, During the injection holding stage, the temperature of the melt buffer device is 210°C to 400°C.

10. The method for manufacturing a continuous fiber reinforced structural member according to claim 4, characterized in that, The material storage stage and the injection and holding stage can be repeated to achieve continuous production of structural components.

11. The method for manufacturing a continuous fiber reinforced structural member according to claim 1, characterized in that, Design the raw material formulation, and feed each component of the raw material formulation into an extruder in proportion for mixing to obtain the melt material, including: The resin matrix, mineral powder and fiber are fed into an extruder in a ratio of (50-60):(1-10):(30-60) to be mixed to obtain a melt material.

12. The method for manufacturing a continuous fiber reinforced structural member according to claim 11, characterized in that, The ratio of resin matrix, mineral powder and fiber is 55:5:

40.

13. The method for manufacturing a continuous fiber reinforced structural member according to claim 11, characterized in that, The resin matrix is ​​made of polypropylene resin.

14. The method for manufacturing a continuous fiber reinforced structural member according to claim 11, characterized in that, The fiber is a continuous fiber, and the Tex value of the continuous fiber is set to be between 2300 g / km and 2500 g / km.

15. The method for manufacturing a continuous fiber reinforced structural member according to claim 11, characterized in that, The extruder is specifically a twin-screw extruder with an internal temperature of 210°C to 400°C, a yield of 110 kg / h to 120 kg / h, and a screw speed of 180 rpm to 200 rpm.

16. The method for manufacturing a continuous fiber reinforced structural member according to claim 1, characterized in that, Preheating thermoplastic composite sheets includes: The thermoplastic composite sheet is heated and then placed into a mold at a temperature of 210°C to 230°C.

17. The method for manufacturing a continuous fiber reinforced structural member according to claim 16, characterized in that, The thermoplastic composite sheet is made of fiber-reinforced resin material.

18. The method for manufacturing a continuous fiber reinforced structural member according to claim 17, characterized in that, The thermoplastic composite sheet uses a fiber-reinforced resin material, which is one of 30% to 60% continuous fiber-reinforced polypropylene resin, carbon fiber-reinforced polypropylene, or nylon.

19. The method for manufacturing a continuous fiber reinforced structural member according to claim 1, characterized in that, Collecting the manufacturing data of the structural component and associating it with the structural component includes: The manufacturing data of the structural component is collected, the received manufacturing data is encapsulated into an information code, and the information code is affixed to the structural component.

20. The method for manufacturing a continuous fiber reinforced structural member according to claim 19, characterized in that, The manufacturing data includes at least one of the following: heating temperature of thermoplastic composite sheet, material mixing parameters, molding parameters, and processor information.

21. A manufacturing apparatus for continuous fiber reinforced structural components, characterized in that, include: An extrusion mixing mechanism includes an extruder, a loss-in-weight metering feeder, and a continuous fiber conveying device. The loss-in-weight metering feeder is connected to the extruder and is used to add raw materials and meter the amount of raw materials added. The continuous fiber conveying device is connected to the extruder and is used to convey fibers and collect fiber conveying data in real time and feed it back to the control system. The injection molding mechanism includes an injection unit, a melt buffer unit, a reversing valve, and a lock-up nozzle. The extruder, the injection unit, the melt buffer unit, and the lock-up nozzle are connected through the reversing valve. The injection molding machine clamping unit is connected to the injection molding mechanism and is used for molding structural parts; The control system is connected to the extrusion mixing mechanism, the injection molding mechanism, and the injection molding machine clamping unit, and is used to realize the automated control and coordination of the manufacturing process of the structural component and to collect the manufacturing data of the structural component; and An information traceability mechanism, connected to the control system, is used to receive manufacturing data collected by the control system and associate the manufacturing data with the structural components.

22. The manufacturing equipment for continuous fiber reinforced structural components according to claim 21, characterized in that, The fiber enters the extruder at the middle position and after the middle position along the material flow direction in the extruder.

23. The manufacturing equipment for continuous fiber reinforced structural components according to claim 21, characterized in that, The continuous fiber conveying device includes a continuous fiber conveying frame, a continuous fiber conveying roller sensor, and a continuous fiber conveying pipe. The fiber inlet ends of the continuous fiber conveying roller sensor and the continuous fiber conveying pipe are both located on the continuous fiber conveying frame. Fiber rolls are placed on the continuous fiber conveying frame. The fibers enter the continuous fiber conveying pipe through the continuous fiber conveying roller sensor. The fiber outlet end of the continuous fiber conveying pipe is connected to the extruder.

24. The manufacturing equipment for continuous fiber reinforced structural components according to claim 21, characterized in that, The injection molding machine clamping unit includes a machine bed, a mold, a robot arm, and a temperature control device. The mold, robot arm, and temperature control device are all mounted on the machine bed, and the mold is connected to the locking nozzle.

25. The manufacturing equipment for continuous fiber reinforced structural components according to claim 21, characterized in that, The information traceability mechanism includes a data storage unit, an information encapsulation unit, and an information code generation device. The data storage unit is connected to the control system to receive and store the structural component manufacturing data that needs to be associated. The information encapsulation unit is connected to the data storage unit and is used to convert the structural component manufacturing data into information codes suitable for printing or display. The information code generation device is connected to the information encapsulation unit and is a device for generating physical QR code labels.

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