Carbon fiber composite unmanned aerial vehicle propeller assembly and fuselage wing rib integrated structure and process

Abstract

The application provides a carbon fiber composite unmanned aerial vehicle propeller assembly and fuselage wing rib integrated forming structure and process in the field of carbon fiber composite material structure integrated forming, and the specific process steps are as follows: (1) carbon fiber prepreg cloth is laid on the propeller assembly and assembled with the foam sandwich fuselage wing rib; (2) the carbon fiber prepreg cloth is laid on the foam sandwich fuselage wing rib structure; (3) the two layers of carbon fiber prepreg cloth cut at both ends of the propeller assembly are stripped and attached to the laid fuselage wing rib carbon fiber prepreg cloth; (4) after coating the release agent, hot pressing is performed in a vacuum environment. The carbon fiber prepreg cloth is laid on the surface of the propeller assembly, then the carbon fiber prepreg cloth at both ends is attached to the fuselage wing rib prepreg cloth, and the integrated forming is performed through the autoclave process, so that the connection strength between the structures is greatly improved, and the connection strength of the structure of the unmanned aerial vehicle in various service environments is ensured.

Description

Technical Field

[0001] This invention relates to the field of integrated molding of carbon fiber composite structures, specifically to an integrated molding structure and process for carbon fiber composite drone propeller components and fuselage wing ribs. Background Technology

[0002] Carbon fiber composites have been widely used in the aerospace field due to their excellent thermal shock resistance, low specific gravity, high strength, corrosion resistance, fatigue resistance, customizable appearance, and ability to be integrally molded. Furthermore, the use of unmanned aerial vehicles (UAVs) for specialized missions such as aerial reconnaissance, surveillance, communication, anti-submarine warfare, and electronic jamming further highlights the advantages of carbon fiber composites in multiple applications.

[0003] Currently, the connections between carbon fiber composite structures mostly employ adhesive bonding or mechanical joining methods. Adhesive bonding requires consideration not only of the compatibility between the selected adhesive and the carbon fiber composite material, but also of the impact of harsh external environments on the adhesive's performance, such as high and low temperatures and humidity. Mechanical joining uses fasteners, which significantly increase the overall weight of the fuselage, raising assembly costs and subsequent maintenance expenses. Furthermore, it necessitates drilling holes in the carbon fiber composite material, causing localized stress concentration and reducing the overall structural strength to some extent. To overcome the shortcomings of mechanical joining, a process for integrally molding the propeller assembly with the fuselage wing ribs has been invented. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide an integrated molding structure and process for carbon fiber composite material drone propeller components and fuselage wing ribs.

[0005] According to the present invention, a process for integrally molding carbon fiber composite material drone propeller assembly and fuselage wing ribs is provided, the specific steps of which are as follows:

[0006] S1. Lay the carbon fiber prepreg fabric on the propeller assembly and assemble the propeller assembly onto the foam sandwich fuselage rib. Cut the carbon fiber prepreg between the two ends of the propeller assembly and the surface of the fuselage rib into six parts along the axis of the assembly.

[0007] S2. The cut carbon fiber prepreg fabric is laid on the foam sandwich fuselage rib structure in two stages. A certain amount of carbon fiber prepreg fabric is left in the part that contacts the propeller assembly, and the excess carbon fiber prepreg fabric is attached to the propeller assembly.

[0008] S3. Peel off the carbon fiber prepreg cut at both ends of the propeller assembly in S1 and attach it to the carbon fiber prepreg fabric of the fuselage wing rib laid in S3.

[0009] S4. Apply release agent to the workbench where the mold is placed and the surface of the mold;

[0010] S5. After aligning the mold and structure on the workbench, place breathable felt and isolation film on them, make a vacuum bag and seal it with sealing strip.

[0011] S6. Vacuum the vacuum bag to ensure there is no air leakage, then place it in the autoclave.

[0012] Preferably, in step S2 above, the cut carbon fiber prepreg fabric is first laid along the inner surface of the foam sandwich fuselage ribs. Where there are round holes, square holes and irregular holes, the carbon fiber prepreg fabric passes through the holes and is then attached to the outer surface of the foam sandwich fuselage ribs so that it just covers the inner and outer surfaces of the fuselage ribs. Then, the second layer of carbon fiber prepreg is first laid on the outer surface of the fuselage rib structure that has already been covered with one layer of prepreg. The second layer is laid by laying the inner layer so that the entire foam sandwich fuselage rib structure is wrapped in two layers of carbon fiber prepreg.

[0013] Preferably, in step S6 above, the autoclave is heated from room temperature to 123°C and kept at that temperature for 2 hours, with a pressure of 0.5 MPa.

[0014] Preferably, the heating rate of the autoclave is 1℃ / min.

[0015] Preferably, in step S6 above, when the temperature drops to 60°C, the pressure of the autoclave is adjusted to 0 MPa.

[0016] Preferably, the cooling rate of the autoclave is 1℃ / min.

[0017] A carbon fiber composite drone propeller assembly and fuselage wing rib integrated molding structure is provided, which adopts a carbon fiber composite drone propeller assembly and fuselage wing rib integrated molding process.

[0018] Preferably, the assembly includes a propeller assembly, fuselage ribs, and a molding die, with the fuselage ribs connected to the propeller assembly and the molding die connected to both the fuselage ribs and the propeller assembly.

[0019] Preferably, the fuselage wing ribs are made of carbon fiber prepreg wrapped with foam core structure, and the propeller assembly is a full carbon fiber composite material round tube formed by winding process.

[0020] Preferably, the forming mold is a slider assembly with an integral structure.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] This invention significantly improves the connection strength between structures by laying carbon fiber prepreg fabric on the surface of the propeller assembly, then bonding the carbon fiber prepreg fabric at both ends to the fuselage wing rib prepreg fabric, and performing integrated molding through a hot autoclave process, thereby ensuring the connection strength of the UAV structure in various service environments. Attached Figure Description

[0023] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0024] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 (a) is an isometric drawing of the mold;

[0026] Figure 2 (b) is a front view of the mold;

[0027] Figure 2 (c) is a triaxial view of the mold;

[0028] Figure 2 (d) is the right view of the mold;

[0029] Figure 2 (e) is a top view of the mold;

[0030] Figure 2 (f) is the left view of the mold. Detailed Implementation

[0031] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0032] Example 1

[0033] The present invention provides a process for integrally molding carbon fiber composite material drone propeller assembly and fuselage wing ribs, the specific steps of which are as follows:

[0034] S1. Both the foam core layer fuselage ribs and the all-carbon fiber propeller assembly have two layers of carbon fiber prepreg laid on their surfaces. The carbon fiber prepreg is cut into a fabric that can completely wrap the fuselage and propeller assembly according to the shape and size of the fuselage ribs and propeller assembly.

[0035] S2. First, lay the carbon fiber prepreg fabric cut in S1 onto the propeller assembly, and then assemble it onto the foam sandwich fuselage rib. Cut the carbon fiber prepreg between the two ends of the propeller assembly and the surface of the fuselage rib into six parts along the axis of the assembly so that it can be bonded to the carbon fiber prepreg of the fuselage later.

[0036] S3. The carbon fiber prepreg fabric cut in S1 is laid on the foam sandwich fuselage wing rib structure in two layers, inside and outside. First, the cut carbon fiber prepreg fabric is laid along the inner surface of the foam sandwich structure. Where there are round holes, square holes and irregular holes, the carbon fiber prepreg fabric passes through the holes and is then attached to the outer surface of the foam sandwich structure so that it just covers the inner and outer surfaces of the structure. Then, the second layer of carbon fiber prepreg is laid on the outer surface of the fuselage wing rib structure that has already been covered with one layer of prepreg. The second layer is laid by laying the inner layer, so that the entire foam sandwich fuselage wing rib structure is wrapped in two layers of carbon fiber prepreg.

[0037] S4. In step (3), a certain amount of carbon fiber prepreg cloth is left in the part that contacts the propeller assembly, and the excess carbon fiber prepreg cloth is attached to the surface of the propeller assembly, so that the connection between the fuselage rib and the propeller assembly is more stable after subsequent curing.

[0038] S5. Peel off the two layers of carbon fiber prepreg fabric cut at both ends of the propeller assembly in step (2) and attach them to the carbon fiber prepreg fabric of the fuselage wing rib laid in step (3).

[0039] S6. After laying the carbon fiber prepreg fabric, apply it three times to the workbench and mold surface using a demolding machine.

[0040] S7. Align the mold and structure on the workbench, place breathable felt and isolation film on it, make a vacuum bag and seal it with sealing strips.

[0041] S8. Vacuum the vacuum bag to ensure there is no leakage, then place it in the autoclave; raise the temperature of the autoclave from room temperature to 123°C at a rate of 1°C / min and hold for 2 hours (the heating rate depends on the curing properties of different prepregs), with a pressure of 0.5 MPa; the cooling rate is 1°C / min, and the pressure is reduced to 0 MPa when the temperature drops to 60°C.

[0042] Example 2

[0043] This invention provides a carbon fiber composite material unmanned aerial vehicle (UAV) propeller assembly integrally molded with the fuselage wing ribs, such as... Figure 1-2As shown, the carbon fiber composite UAV propeller assembly and fuselage wing ribs are integrally molded using the process described in Example 1. This includes a propeller assembly, fuselage wing ribs, and a molding die. The fuselage wing ribs are connected to the propeller assembly, and the molding die connects both the fuselage wing ribs and the propeller assembly. Specifically, the fuselage wing ribs are a carbon fiber prepreg-wrapped foam sandwich structure, the propeller assembly is a fully carbon fiber composite cylindrical tube formed by a winding process, and the molding die is a slider assembly that mates with the overall structure.

[0044] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "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. They are 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.

[0045] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A process for integrally molding carbon fiber composite material drone propeller assembly and fuselage wing ribs, characterized in that, The specific steps are as follows: S1. Lay the carbon fiber prepreg fabric on the propeller assembly and assemble the propeller assembly onto the foam sandwich fuselage rib. Cut the carbon fiber prepreg between the two ends of the propeller assembly and the surface of the fuselage rib into six parts along the axis of the assembly. S2. The cut carbon fiber prepreg fabric is laid on the foam sandwich fuselage rib structure in two stages. A certain amount of carbon fiber prepreg fabric is left in the part that contacts the propeller assembly, and the excess carbon fiber prepreg fabric is attached to the propeller assembly. S3. Peel off the carbon fiber prepreg cut at both ends of the propeller assembly in S1 and attach it to the carbon fiber prepreg fabric of the fuselage wing rib laid in S2. S4. Apply release agent to the workbench where the mold is placed and the surface of the mold; S5. After aligning the mold and structure on the workbench, place breathable felt and isolation film on them, make a vacuum bag and seal it with sealing strips. S6. Vacuum the vacuum bag to ensure there is no air leakage, then place it in the autoclave.

2. The integral molding process of carbon fiber composite UAV propeller assembly and fuselage wing ribs according to claim 1, characterized in that, In step S2 above, the cut carbon fiber prepreg fabric is first laid along the inner surface of the foam sandwich fuselage ribs. Where there are round holes, square holes and irregular holes, the carbon fiber prepreg fabric passes through the holes and is then attached to the outer surface of the foam sandwich fuselage ribs so that it just covers the inner and outer surfaces of the fuselage ribs. Then, the second layer of carbon fiber prepreg is first laid on the outer surface of the fuselage rib structure that has already been covered with one layer of prepreg. The second layer is laid by laying the inner layer so that the entire foam sandwich fuselage rib structure is wrapped in two layers of carbon fiber prepreg.

3. The integral molding process of carbon fiber composite UAV propeller assembly and fuselage wing ribs according to claim 1, characterized in that, In step S6 above, the autoclave is heated from room temperature to 123°C and kept at that temperature for 2 hours, with a pressure of 0.5 MPa.

4. The integral molding process of carbon fiber composite UAV propeller assembly and fuselage wing ribs according to claim 3, characterized in that, The autoclave has a heating rate of 1℃ / min.

5. The integral molding process of carbon fiber composite UAV propeller assembly and fuselage wing ribs according to claim 1, characterized in that, In step S6 above, when the temperature drops to 60°C, the pressure of the autoclave is adjusted to 0 MPa.

6. The integral molding process of carbon fiber composite UAV propeller assembly and fuselage wing ribs according to claim 5, characterized in that, The autoclave has a cooling rate of 1℃ / min.

7. A carbon fiber composite material unmanned aerial vehicle propeller assembly integrally formed with the fuselage wing ribs, characterized in that, The carbon fiber composite UAV propeller assembly and fuselage wing ribs are integrally molded using the process described in any one of claims 1-6.

8. The carbon fiber composite UAV propeller assembly and fuselage wing rib integral molding structure according to claim 7, characterized in that, It includes a propeller assembly, fuselage ribs, and a molding die. The fuselage ribs are connected to the propeller assembly, and the molding die is connected to both the fuselage ribs and the propeller assembly.

9. The carbon fiber composite UAV propeller assembly and fuselage wing rib integral molding structure according to claim 8, characterized in that, The fuselage wing ribs are made of carbon fiber prepreg wrapped with foam core, and the propeller assembly is a full carbon fiber composite material round tube formed by winding process.

10. The carbon fiber composite UAV propeller assembly and fuselage wing rib integral molding structure according to claim 8, characterized in that, The forming mold is a slider assembly with an integral structure.

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