Large-angle honeycomb sandwich structure forming auxiliary device and forming method

Abstract

The invention discloses a forming auxiliary device, belongs to the technical field of large-angle honeycomb sandwich structures, and particularly relates to a large-angle honeycomb sandwich structure forming auxiliary device and a forming method. In the forming and curing process of a large-angle honeycomb sandwich structure, the viscosity of resin is gradually reduced along with temperature rise, so that the fluidity of the resin is increased; meanwhile, the friction coefficient between the prepreg and the honeycomb core is gradually reduced; a rubber auxiliary forming die with an inflation nozzle and a vacuum valve is manufactured, the auxiliary forming die is of a hollow structure, one side of the auxiliary forming die is matched with the honeycomb bevel angle of the large-angle honeycomb sandwich structure, and the other side of the auxiliary forming die is 10-20 degrees; the rubber auxiliary forming die can effectively balance the pressure difference in the chamfer curing process of the edge of the honeycomb core, reduce the lateral pressure of the honeycomb, avoid the slippage phenomenon of the honeycomb and ensure the quality of a large-angle honeycomb sandwich structure product through the friction force with the die and the breathable felt and the internal structural tension.

Description

Technical Field

[0001] The invention discloses a forming auxiliary device, belongs to the technical field of large-angle honeycomb sandwich structures, and particularly relates to a forming auxiliary device and a forming method for a large-angle honeycomb sandwich structure. Background Art

[0002] In the field of aerospace, honeycomb sandwich structures are widely used in the manufacture of aircraft and spacecraft as an important composite material structure. This structure is formed into a whole through the curing of panels, honeycomb core layers and adhesives. It not only has excellent bending stiffness, but also can effectively transmit shear force. However, in practical applications, honeycomb sandwich structures face a problem: after the honeycomb core material increases the cross-sectional height, it becomes difficult to connect with adjacent structures. In order to solve this problem, a slope transition method is usually used to connect the sandwich structure to the laminate structure, thereby forming a honeycomb bevel zone.

[0003] However, due to the influence of the lateral compression resistance of the honeycomb, the interlayer friction coefficient, the chamfer of the honeycomb core edge and the curing pressure difference, the honeycomb bevel area is prone to honeycomb slippage, resulting in extrusion deformation of the honeycomb core cell and wrinkling of the skin fiber. In particular, due to the limitations of structural load and design space, when the chamfer design of the honeycomb core edge is greater than 25°, the honeycomb sandwich structure is very likely to slip during curing, seriously affecting the quality of the product.

[0004] Therefore, combining the mechanism of honeycomb slip, a large-angle honeycomb sandwich structure forming method and auxiliary device are invented to avoid and improve the oblique angle slip of the large-angle honeycomb sandwich structure, which is of great significance for improving the product quality of honeycomb sandwich structural parts. Summary of the invention

[0005] Purpose of the invention: To provide a large-angle honeycomb sandwich structure forming auxiliary device and forming method to solve the above-mentioned problems.

[0006] Technical solution: A large-angle honeycomb sandwich structure forming auxiliary device and forming method, the rubber auxiliary forming mold comprises: a large-angle honeycomb sandwich structure, a rubber auxiliary forming mold, a breathable felt, a sealing strip and a forming mold;

[0007] In a further embodiment, the rubber-assisted molding mold is installed on the molding mold, the rubber-assisted molding mold is a hollow structure forming an installation cavity, the large-angle honeycomb sandwich structure is installed in the installation cavity of the rubber-assisted molding mold, the breathable felt and the sealing strip are installed between the rubber-assisted molding mold and the molding mold, and the sealing strip is located on the outside of the breathable felt.

[0008] In a further embodiment, the installation cavity of the rubber-assisted molding mold matches the surface of the large-angle honeycomb sandwich structure, one side of the rubber-assisted molding mold matches the honeycomb bevel angle of the large-angle honeycomb sandwich structure, and the other side is inclined by 10°-20°.

[0009] In a further embodiment, the interior of the high-angle honeycomb sandwich structure is a honeycomb sandwich structure.

[0010] In a further embodiment, the inner surface of the rubber-assisted molding mold is provided with a fiber reinforcement layer.

[0011] In a further embodiment, an inflation nozzle and a vacuum valve are provided on the surface of the rubber-assisted molding mold, the inflation nozzle is installed on one side of the hypotenuse of the rubber-assisted molding mold, and the vacuum valve is installed on the bottom surface of the rubber-assisted molding mold and connected to the breathable felt.

[0012] In a further embodiment, the rubber auxiliary molding mold has a structure that is narrow at the top and wide at the bottom, and an air cavity is provided at the connection between the upper part and the lower part.

[0013] A molding method of a large-angle honeycomb sandwich structure molding auxiliary device is implemented by using the above-mentioned large-angle honeycomb sandwich structure molding auxiliary device, and the molding method comprises:

[0014] Step 1: Make a rubber auxiliary molding mold, the inner mold matches the inner surface of the large-angle honeycomb sandwich structure. Prefabricate the inflation nozzle and vacuum nozzle, and install the valve;

[0015] Step 2: Laying a large-angle honeycomb sandwich structure on the forming mold;

[0016] Step 3, assemble the rubber auxiliary molding die, pre-pressurize the inflation nozzle and close the inflation valve, match and fit, and shape;

[0017] Step 4: Use a sealing strip to seal the periphery of the rubber-assisted molding die with the molding die, and draw a vacuum through the vacuum valve of the rubber-assisted molding die;

[0018] Step 5, open the valve of the rubber auxiliary molding mold inflation nozzle, connect the tank pressure, balance the inside and outside, and ensure the pressure;

[0019] Step 6: The outer surface quality is ensured by the molding die, and the rubber auxiliary molding die ensures the inner surface quality;

[0020] Step 7: Curing and demoulding.

[0021] The present invention has the following beneficial effects:

[0022] 1. The rubber-assisted molding die can effectively balance the pressure difference during the chamfering and curing process of the honeycomb core edge through the friction between the mold and the breathable felt, as well as the internal structural tension, reduce the lateral pressure of the honeycomb, avoid honeycomb slippage, and ensure the quality of large-angle honeycomb sandwich structure products.

[0023] 2. The rubber-assisted molding mold is elastic and deformable, matching and compensating for honeycomb processing and paving errors to ensure pressure transmission.

[0024] 3. Simple packaging, reducing the risk of vacuum bag bridging.

[0025] 4. The rubber-assisted forming mold and the forming die are used to ensure the inner and outer surface quality of the large-angle honeycomb sandwich structure.

[0026] 5. The rubber-assisted molding mold can be reused, reducing the loss of auxiliary materials such as vacuum bags and reducing manufacturing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the large-angle honeycomb sandwich structure of the present invention.

[0028] Figure 2 It is a schematic diagram of the rubber auxiliary molding die of the present invention.

[0029] Figure 3 It is a schematic diagram of packaging of a large-angle honeycomb sandwich structure of the present invention.

[0030] Figure 4 It is a schematic diagram of the use of the rubber auxiliary molding die of the present invention.

[0031] Figure 5 It is a schematic diagram of the principle of the rubber auxiliary forming mold of the present invention.

[0032] Reference numerals: high-angle honeycomb sandwich structure 1, honeycomb core 1.1, rubber-assisted forming mold 2, inflation nozzle 2.1, vacuum valve 2.2, air-permeable felt 3, sealing strip 4, forming mold 5. DETAILED DESCRIPTION

[0033] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] Embodiment 1:

[0035] A large-angle honeycomb sandwich structure forming auxiliary device, comprising: the rubber auxiliary forming mold 2 comprises: a large-angle honeycomb sandwich structure 1, a rubber auxiliary forming mold 2, a breathable felt 3, a sealing strip 4 and a forming mold 5;

[0036] In one embodiment, Figures 1 to 5 As shown, the rubber auxiliary molding mold 2 is installed on the molding mold 5, the rubber auxiliary molding mold 2 is a hollow structure forming an installation cavity, the large-angle honeycomb sandwich structure 1 is installed in the installation cavity of the rubber auxiliary molding mold 2, the air-permeable felt 3 and the sealing strip 4 are installed between the rubber auxiliary molding mold 2 and the molding mold 5, and the sealing strip 4 is located on the outside of the air-permeable felt 3.

[0037] In one embodiment, Figures 1 to 5 As shown, the installation cavity of the rubber-assisted molding die 2 matches the surface of the large-angle honeycomb sandwich structure 1, one side of the rubber-assisted molding die 2 matches the honeycomb bevel angle of the large-angle honeycomb sandwich structure, and the other side is inclined by 10°-20°.

[0038] In one embodiment, Figures 1 to 5 As shown, the interior of the high-angle honeycomb sandwich structure 1 is a honeycomb sandwich core 1.1 structure.

[0039] In one embodiment, Figures 1 to 5 As shown, the inner surface of the rubber auxiliary molding mold 2 is provided with a fiber reinforcement layer.

[0040] In one embodiment, Figures 1 to 5 As shown, the surface of the rubber-assisted molding mold 2 is provided with an inflation nozzle 2.1 and a vacuum valve 2.2. The inflation nozzle 2.1 is installed on one side of the hypotenuse of the rubber-assisted molding mold 2, and the vacuum valve 2.2 is installed on the bottom surface of the rubber-assisted molding mold 2 and connected to the breathable felt 3.

[0041] In one embodiment, Figures 1 to 5 As shown, the rubber auxiliary molding mold 2 is narrow at the top and wide at the bottom, and an air cavity is provided at the connection between the upper part and the lower part.

[0042] In one embodiment, Figures 1 to 5 As shown, the present invention uses a rubber-assisted molding die 2 with an inflation nozzle 2.1 and a vacuum valve 2.2. The rubber-assisted molding die 2 is a hollow structure, one side of which matches the honeycomb bevel of the large-angle honeycomb sandwich structure, and the other side is 10°-20°.

[0043] In one embodiment, Figures 1 to 5 As shown, the rubber auxiliary molding mold 2 is made on the inner surface of the large-angle honeycomb sandwich structure, and a fiber reinforcement layer can be added to ensure the shape.

[0044] In one embodiment, Figures 1 to 5 As shown, the rubber auxiliary molding die 2 is made of rubber material, which is elastic, deformable, matching and compensating to ensure the fit. The rubber auxiliary molding die 2 is soft and deformable, which is easy to demould.

[0045] Embodiment 2:

[0046] A molding method of a large-angle honeycomb sandwich structure molding auxiliary device is implemented by using the above-mentioned large-angle honeycomb sandwich structure molding auxiliary device, and the molding method comprises:

[0047] Step 1: Make a rubber auxiliary molding mold 2, the inner mold matches the inner surface of the large-angle honeycomb sandwich structure. Prefabricate the inflation nozzle 2.1, the vacuum nozzle, and install the valve;

[0048] Step 2: Laying a large-angle honeycomb sandwich structure on the forming mold 5;

[0049] Step 3, assemble the rubber auxiliary molding die 2, pre-pressurize the inflation nozzle 2.1 and close the inflation valve, match and fit, and shape;

[0050] Step 4, using a sealing strip 4 to seal the periphery of the rubber auxiliary molding mold 2 and the molding mold 5, and drawing a vacuum through the vacuum valve 2.2 of the rubber auxiliary molding mold 2;

[0051] Step 5, open the valve of the rubber auxiliary forming mold 2 inflation nozzle 2.1, connect the tank pressure, balance the inside and outside, and ensure the pressure;

[0052] Step 6: The outer surface quality is ensured by the molding die 5, and the rubber auxiliary molding die 2 ensures the inner surface quality;

[0053] Step 7: Curing and demoulding.

[0054] Working principle: A rubber auxiliary molding mold 2 is manufactured, and the inner mold matches the inner surface of a large-angle honeycomb sandwich structure 1.

[0055] The rubber auxiliary molding die 2 is a hollow structure, one side of which matches the honeycomb bevel angle of the large-angle honeycomb sandwich structure, and the other side is 10°-20°.

[0056] The rubber-assisted molding die 2 can add a fiber reinforcement layer to ensure the shape.

[0057] The rubber auxiliary forming mold 2 prefabricates an inflation nozzle and a vacuum nozzle, and installs a valve.

[0058] Laying a large-angle honeycomb sandwich structure 1 on the forming mold 5;

[0059] Lay the air-permeable felt 3 and the isolation membrane around the large-angle honeycomb sandwich structure 1;

[0060] Combine the rubber auxiliary molding die 2, pre-pressurize through the inflation nozzle 2.1, match and fit, close the inflation valve, and maintain the shape;

[0061] Use a sealing strip 4 to seal the periphery of the rubber auxiliary molding die 2 and the molding die 5, and draw a vacuum through the vacuum valve 2.2 of the rubber auxiliary molding die;

[0062] Open the rubber auxiliary forming mold inflation nozzle valve 2.1, connect the tank pressure, balance the inside and outside, and ensure the pressure;

[0063] The outer surface quality is ensured by the forming die 5, and the inner surface quality is ensured by the rubber auxiliary forming die 2;

[0064] Curing and demoulding.

[0065] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A large-angle honeycomb sandwich structure forming auxiliary device, characterized in that: The rubber auxiliary molding die comprises: a large-angle honeycomb sandwich structure, a rubber auxiliary molding die, a breathable felt, a sealing strip and a molding die; The rubber auxiliary molding mold is installed on the molding mold. The rubber auxiliary molding mold is a hollow structure forming an installation cavity. The large-angle honeycomb sandwich structure is installed in the installation cavity of the rubber auxiliary molding mold. The breathable felt and the sealing strip are installed between the rubber auxiliary molding mold and the molding mold, and the sealing strip is located on the outside of the breathable felt.

2. A large-angle honeycomb sandwich structure forming auxiliary device according to claim 1, characterized in that: The installation cavity of the rubber-assisted molding die matches the surface of the large-angle honeycomb sandwich structure, one side of the rubber-assisted molding die matches the honeycomb bevel of the large-angle honeycomb sandwich structure, and the other side is inclined by 10°-20°.

3. The large-angle honeycomb sandwich structure forming auxiliary device according to claim 1, characterized in that: The interior of the large-angle honeycomb sandwich structure is a honeycomb sandwich structure.

4. The large-angle honeycomb sandwich structure forming auxiliary device according to claim 1, characterized in that: The inner surface of the rubber auxiliary forming mold is provided with a fiber reinforcement layer.

5. The large-angle honeycomb sandwich structure forming auxiliary device according to claim 1, characterized in that: The surface of the rubber auxiliary molding mold is provided with an inflation nozzle and a vacuum valve. The inflation nozzle is installed on one side of the hypotenuse of the rubber auxiliary molding mold, and the vacuum valve is installed on the bottom surface of the rubber auxiliary molding mold and connected to the breathable felt.

6. The large-angle honeycomb sandwich structure forming auxiliary device according to claim 1, characterized in that: The rubber auxiliary forming mold is in a structure that is narrow at the top and wide at the bottom, and an air cavity is provided at the connection between the upper part and the lower part.

7. A forming method of a large-angle honeycomb sandwich structure forming auxiliary device, characterized in that: The method is implemented by using a large-angle honeycomb sandwich structure forming auxiliary device as described in any one of claims 1 to 6, and the forming method comprises: Step 1: Make a rubber auxiliary molding mold, the inner mold matches the inner surface of the large-angle honeycomb sandwich structure. Prefabricate the inflation nozzle and vacuum nozzle, and install the valve; Step 2: Laying a large-angle honeycomb sandwich structure on the forming mold; Step 3, assemble the rubber auxiliary molding die, pre-pressurize the inflation nozzle and close the inflation valve, match and fit, and shape; Step 4: Use a sealing strip to seal the periphery of the rubber-assisted molding die with the molding die, and draw a vacuum through the vacuum valve of the rubber-assisted molding die; Step 5, open the valve of the rubber auxiliary molding mold inflation nozzle, connect the tank pressure, balance the inside and outside, and ensure the pressure; Step 6: The outer surface quality is ensured by the molding die, and the rubber auxiliary molding die ensures the inner surface quality; Step 7: Curing and demoulding.

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