Winglet for unmanned aerial vehicle

Abstract

The utility model belongs to the technical field of composite material parts and manufacturing, and particularly relates to a winglet for an unmanned aerial vehicle. The technical problems that the energy consumption is high and the production efficiency is low due to the fact that autoclave forming, vacuum bag forming and other forming modes are adopted are solved. According to the technical scheme, the winglet for the unmanned aerial vehicle comprises an upper skin; the mold further comprises an upper mold assembly, a lower mold assembly and a demolding assembly. The PMI foam is used, so that the structural rigidity of the winglet is increased, the weight of the composite winglet is obviously reduced compared with that of a metal winglet, the selected compression molding process can be used for efficient production of composite materials, the composite winglet has the advantages of high efficiency and low cost, post-processing of composite parts can be reduced, and the composite winglet is suitable for batch production.

Description

Technical Field

[0001] The utility model belongs to the technical field of composite material parts and manufacturing, and in particular relates to a winglet for an unmanned aerial vehicle. Background Art

[0002] In the field of aviation, as the aircraft moves forward, the wingtip vortex extends backward to form a wake vortex, which will produce induced drag. In order to reduce the induced drag, winglets came into being. Generally, the upturned section at the end of the wing is called a winglet, which can block the airflow from the lower wing surface to flow around the upper wing surface, thereby weakening the strength of the wingtip vortex, which is of great significance for reducing flight fuel consumption, improving flight economy and environmental protection. Early winglets were made of metal materials, which are heavy. Composite materials are widely used in aerospace, automotive industry, machinery manufacturing, sports and leisure fields due to their advantages such as light weight, high strength, corrosion resistance, high temperature resistance and good fatigue resistance. Widely used. In the existing technology, the aerospace field uses a lot of hot autoclave molding, vacuum bag molding and other molding methods for composite materials. They have high energy consumption and low production efficiency. After the parts are formed, subsequent processing is generally required to obtain net size products. The molding process can be used for efficient production of composite materials. It has the advantages of high efficiency and low cost, and can reduce the post-processing of composite parts to achieve the required size and shape accuracy of the product. It is suitable for mass production of composite parts. However, after the molding work is completed, it is not convenient to demold the product after the film is pressed during the demolding work, which leads to damage. Utility Model Content

[0003] In order to overcome the problems of high energy consumption and low production efficiency in the process of manufacturing winglets by using molding methods such as autoclave molding and vacuum bag molding, a winglet made by a molding process is invented, and the demoulding of the mold is improved.

[0004] The technical solution of the utility model is: a winglet for a drone, comprising an upper skin; an upper mold assembly, a lower mold assembly and a demoulding assembly; a lower skin is arranged at the lower end of the upper skin; a filling foam core material is arranged between the upper skin and the lower skin; a trailing edge is arranged on the upper skin; a leading edge is arranged on the lower skin; an upper mold assembly for film pressing is arranged on the lower mold assembly; and a demoulding assembly for demoulding is arranged on the lower mold assembly.

[0005] Preferably, the material is placed on the lower mold assembly, the upper mold assembly is placed on the lower mold assembly, and the mold is placed in a hot press to perform the film pressing work. After completion, water is injected into the demolding assembly to demold the materials on the upper mold assembly and the lower mold assembly.

[0006] Preferably, the upper mold assembly includes a first fixed block and a film pressing block; a symmetrical film pressing block is fixedly connected to the upper end of the first fixed block, and the film pressing block on the first fixed block is used as a film press for subsequent work.

[0007] Preferably, the lower mold assembly includes a second fixed block; a mold groove and demolding holes; the lower end of the first fixed block is hinged with the second fixed block; the upper end of the second fixed block is provided with a symmetrical mold groove; the mold groove is adapted to the film pressing block; the lower end of the inner wall of the mold groove is penetrated with evenly distributed demolding holes, and the material is placed on the mold groove, and then covered with the first fixed block and placed in the hot press to perform hot pressing. After the work is completed, the two mold grooves are formed into upper and lower skins through hot pressing of the film pressing block.

[0008] Preferably, the demoulding assembly includes a water storage box, a water purification box, a water inlet pipe, an air outlet, a liquid drainage groove, a first baffle and a second baffle; the lower end of the second fixed block is fixedly connected to the water storage box; the front end of the water storage box is fixedly connected to the water purification box; the front end of the water purification box is fixedly connected to the water inlet pipe; the upper end of the water storage box is penetrated by uniformly distributed air outlets; the inner wall of the air outlet and the inner wall of the demoulding hole are in the same plane; the lower end of the water storage box is penetrated by a liquid drainage groove; the inner wall of the liquid drainage groove is fixedly connected to the first baffle; the first baffle A second baffle is rotatably provided at the lower end of the plate. Water is injected into the water inlet pipe, and the water flows into the water storage box through the water purification box. The temperature of the water storage box itself is relatively high. When it contacts the water from the water inlet pipe, the generated water vapor flows into the upper end of the demoulding hole through the air outlet, thereby demolding the finished product on the mold groove through the water vapor. When drainage is required, the second baffle is rotated so that the notch of the second baffle is in the same plane as the notch of the first baffle, thereby draining the water from the water storage box.

[0009] Preferably, the upper skin and the lower skin are made of carbon fiber or glass fiber composite materials. The upper skin and the lower skin are made of carbon fiber or glass fiber composite materials, which can reduce weight and facilitate flying.

[0010] Preferably, the filling foam core material is PMI foam, which is connected to the upper and lower skins by adhesive film curing bonding. Using this material will make the overall quality clearer, but the overall strength is higher and the connectivity is stronger.

[0011] Preferably, after molding, it is connected to the end ribs and the leading and trailing edges of the wing box section by bolts and can be disassembled as a whole. It is characterized in that the wingtip winglet includes an upper skin, a lower skin and a filling foam core material, and the upper skin and the lower skin can be made by a molding device.

[0012] Beneficial effects of the utility model:

[0013] 1. Place the material on the lower mold assembly, place the upper mold assembly on the lower mold assembly, place the mold in a hot press, and perform film pressing. After completion, inject water into the demoulding assembly to demould the materials on the upper mold assembly and the lower mold assembly;

[0014] 2. The use of PMI foam increases the structural rigidity of the winglet, and the composite winglet is significantly lighter than the metal winglet. The selected compression molding process can be used for efficient production of composite materials, which has the advantages of high efficiency and low cost, can reduce the post-processing of composite parts, and is suitable for mass production;

[0015] 3. By injecting water into the water inlet pipe, the water flows into the water storage box through the water purification box. The water storage box itself has a high temperature. When it contacts the water from the water inlet pipe, the generated water vapor flows into the upper end of the demoulding hole through the air outlet, thereby demoulding the finished product on the mold groove through the water vapor. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 What is shown is a three-dimensional structural schematic diagram of a winglet for a UAV of the utility model;

[0017] Figure 2 What is shown is a three-dimensional structural schematic diagram of an upper mold assembly and a lower mold assembly of a winglet for a drone of the utility model;

[0018] Figure 3 What is shown is a top view of a three-dimensional structure of a lower mold assembly of a winglet for a drone according to the utility model;

[0019] Figure 4 What is shown is a three-dimensional structural schematic diagram of a demoulding component of a winglet for a drone of the present invention;

[0020] Figure 5 Shown is a schematic diagram of the three-dimensional structure disassembly of a demoulding component of a winglet for an unmanned aerial vehicle according to the utility model.

[0021] The markings in the accompanying drawings are: 1-upper skin, 2-lower skin, 3-filling foam core material, 4-leading edge, 5-trailing edge, 6-upper mold assembly, 601-first fixed block, 602-film pressing block, 7-lower mold assembly, 701-second fixed block, 702-mold groove, 703-demolding hole, 8-demolding assembly, 801-water storage box, 802-water purification box, 803-water inlet pipe, 804-air outlet, 805-drainage trough, 806-first baffle, 807-second baffle. DETAILED DESCRIPTION

[0022] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0023] See also Figure 1 The utility model provides an embodiment: a winglet for a drone, comprising an upper skin 1; also comprising an upper mold assembly 6, a lower mold assembly 7 and a demolding assembly 8; a lower skin 2 is arranged at the lower end of the upper skin 1; a filling foam core material 3 is arranged between the upper skin 1 and the lower skin 2; a trailing edge 5 is arranged on the upper skin 1; a leading edge 4 is arranged on the lower skin 2; an upper mold assembly 6 for film pressing is arranged on the lower mold assembly 7; a demolding assembly 8 for demolding is arranged on the lower mold assembly 7.

[0024] See also Figure 1 In this embodiment, the upper skin 1 and the lower skin 2 are made of carbon fiber or glass fiber composite materials, and the filling foam core material 3 is PMI foam, which is connected to the upper and lower skins by curing adhesive film. After molding, it is connected to the end ribs and the leading and trailing edges of the wing box section by bolts and can be disassembled as a whole. It is characterized in that the wingtip winglet includes an upper skin 1, a lower skin 2 and a filling foam core material 3.

[0025] See also Figure 2-3 In this embodiment, the upper mold assembly 6 includes a first fixed block 601 and a film pressing block 602; the upper end of the first fixed block 601 is fixedly connected with a symmetrical film pressing block 602, and the lower mold assembly 7 includes a second fixed block 701; a mold groove 702 and a demolding hole 703; the lower end of the first fixed block 601 is hinged with the second fixed block 701; the upper end of the second fixed block 701 is provided with a symmetrical mold groove 702; the mold groove 702 is adapted to the film pressing block 602; the lower end of the inner wall of the mold groove 702 is penetrated with evenly distributed demolding holes 703.

[0026] See also Figure 2-5 In the present embodiment, the demoulding assembly 8 comprises a water storage box 801, a water purification box 802, a water inlet pipe 803, an air outlet hole 804, a drainage groove 805, a first baffle 806 and a second baffle 807; the lower end of the second fixed block 701 is fixedly connected with the water storage box 801; the front end of the water storage box 801 is fixedly connected with the water purification box 802 in a through-type; the front end of the water purification box 802 is fixedly connected with the water inlet pipe 803 in a through-type; the upper end of the water storage box 801 is penetrated with uniformly distributed air outlet holes 804; the inner wall of the air outlet hole 804 is in the same plane as the inner wall of the demoulding hole 703; the lower end of the water storage box 801 is penetrated with a drainage groove 805; the inner wall of the drainage groove 805 is fixedly connected with the first baffle 806; the lower end of the first baffle 806 is rotatably provided with a second baffle 807.

[0027] Mould preparation, prepare the mould according to relevant requirements, prepreg blanking, use blanking machine to blank according to product drawings, core material preparation, filling foam core material according to the parts CATIA three-dimensional digital model, process margin and other requirements, adopt CNC machining, prepreg layering, product prepreg layering according to relevant technical conditions, mould closing, check whether the layer is compacted during the mould closing process, the installation order of each insert, check the mould clearance according to the process flow card of the corresponding part after mould closing and compaction, to ensure that the part reaches the theoretical compaction state, after confirming that the mould closing state is good, put the product on the workbench of the hot press, cure, products with upper and lower moulds, use hot press to cure by placing the material on the mould groove 702, and then close the cover through the first fixing block 601 and put it into the hot press to perform hot pressing;

[0028] After demoulding, the temperature is lowered to below 60°C and the mold is removed from the hot press. Water is injected into the water inlet pipe 803, and the water flows into the water storage box 801 through the water purification box 802. The water storage box 801 itself has a relatively high temperature. When it contacts the water from the water inlet pipe 803, the generated water vapor flows into the upper end of the demoulding hole 703 through the air outlet 804, thereby demoulding the finished product on the mold groove 702 through the water vapor. When drainage is required, the second baffle 807 is rotated so that the notch of the second baffle 807 and the notch of the first baffle 806 are in the same plane, thereby draining the water from the water storage box 801.

[0029] Inspection and testing: the product appearance, size, thickness, weight, etc. are inspected according to the drawings, digital models and acceptance documents. After passing the inspection, the product is subjected to non-destructive testing according to the acceptance documents. The prepreg used for the ply is T300-grade medium-temperature cured epoxy resin carbon fiber fabric prepreg or medium-temperature cured epoxy resin glass fiber fabric prepreg, with a surface density of 100-200g / m2. The curing parameters are: when the mold is heated to 80°C, pressurization begins, the pressure is 9MPa, and the air is released at least twice; after heating to 120°C, keep warm for 90-100min, and the heating rate is 0-10°C / min; after the insulation is over, remove the live block locating pin, release the pressure and cool down to below 60°C, and the cooling rate is 0-3°C / min.

[0030] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of those skilled in the art without departing from the purpose of the present invention.

Claims

1. A winglet for an unmanned aerial vehicle, comprising an upper skin (1); characterized in that: It also includes an upper mold assembly (6), a lower mold assembly (7) and a demoulding assembly (8); a lower skin (2) is arranged at the lower end of the upper skin (1); a filling foam core material (3) is arranged between the upper skin (1) and the lower skin (2); a trailing edge (5) is arranged on the upper skin (1); a leading edge (4) is arranged on the lower skin (2); an upper mold assembly (6) for film pressing is arranged on the lower mold assembly (7); and a demoulding assembly (8) for demoulding is arranged on the lower mold assembly (7).

2. The winglet for a drone according to claim 1, characterized in that: The upper mold assembly (6) comprises a first fixed block (601) and a film pressing block (602); the upper end of the first fixed block (601) is fixedly connected to a symmetrical film pressing block (602).

3. The winglet for a drone according to claim 2, characterized in that: The lower mold assembly (7) includes a second fixed block (701); a mold groove (702) and a demoulding hole (703); the lower end of the first fixed block (601) is hinged with the second fixed block (701); the upper end of the second fixed block (701) is provided with a symmetrical mold groove (702); the mold groove (702) is adapted to the film pressing block (602); and the lower end of the inner wall of the mold groove (702) is penetrated by evenly distributed demoulding holes (703).

4. The winglet for a drone according to claim 3, characterized in that: The demoulding assembly (8) comprises a water storage box (801), a water purification box (802), a water inlet pipe (803), an air outlet (804), a liquid drain groove (805), a first baffle (806) and a second baffle (807); the lower end of the second fixed block (701) is fixedly connected to the water storage box (801); the front end of the water storage box (801) is fixedly connected to the water purification box (802); the front end of the water purification box (802) is fixedly connected to the water inlet pipe (803). The water pipe (803) is provided at the upper end of the water storage box (801) with evenly distributed air outlet holes (804); the inner wall of the air outlet holes (804) and the inner wall of the demoulding hole (703) are in the same plane; the lower end of the water storage box (801) is provided with a liquid drainage groove (805); the inner wall of the liquid drainage groove (805) is fixedly connected with a first baffle (806); and the lower end of the first baffle (806) is rotatably provided with a second baffle (807).

5. The winglet for a drone according to claim 1, characterized in that: The upper skin (1) and the lower skin (2) are made of carbon fiber or glass fiber composite materials.

6. The winglet for a drone according to claim 1, characterized in that: The filling foam core material (3) is PMI foam, which is connected to the upper and lower skins by curing adhesive bonding through an adhesive film.

7. The winglet for a drone according to claim 1, characterized in that: After being formed, the winglet is connected to the end ribs and the leading and trailing edges of the wing box section by bolts and can be disassembled as a whole. The winglet is characterized in that it comprises an upper skin (1), a lower skin (2) and a filling foam core material (3).

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