Hollow sandwich structure, manufacturing method thereof and pressure-resistant sandwich plate

Abstract

The invention discloses a hollowed-out sandwich structure, a manufacturing method thereof and a pressure-resistant sandwich panel, the hollowed-out sandwich structure is formed by folding a planar hollowed-out grid, a convex plane, a concave plane and a connecting surface are generated after folding, a hollowed-out gap is generated between the adjacent concave plane and convex plane, and the concave plane and the convex plane are reversible; the two sides of the hollow sandwich structure are bonded with surface plates to form an integral pressure-resistant sandwich plate; the hollow interlayer structure not only can be used as a planar pressure-resistant interlayer, but also can be used as a curved-surface or annular pressure-resistant interlayer, so that the applicability is very high; in addition, the invention also has the advantages of high compression strength, good impact resistance, low cost, convenient manufacture and the like.

Description

Technical Field

[0001] The invention relates to a lightweight plate shell structure, and in particular to a hollow sandwich structure, a manufacturing method thereof and a pressure-resistant sandwich plate. Background Art

[0002] At present, the demand for lightweight structures in the fields of submersibles, aerospace, automobiles, ships, and construction is increasing, and honeycomb sandwich panels are one of the most widely used lightweight plate and shell structures. Honeycomb sandwich panels include an upper plate, a lower plate, and a honeycomb sandwich layer in the middle, but honeycomb sandwich panels are only suitable for structures with little change in surface curvature. Summary of the invention

[0003] Purpose of the invention: The first purpose of the present invention is to provide a hollow sandwich structure capable of forming a plane, a curved surface and an annular structure; the second purpose of the present invention is to provide a method for manufacturing the hollow sandwich structure; the third purpose of the present invention is to provide a pressure-resistant sandwich plate with high compressive strength and good impact resistance based on the hollow sandwich structure.

[0004] Technical solution: The hollow sandwich structure of the present invention comprises a square grid of (4n±1)×(4n±1), wherein n is an integer greater than or equal to 1, and the square grids with even numbers of rows and columns are hollowed out;

[0005] A square grid with rows and columns of 1 bulges upward to form a convex plane, or sinks downward to form a concave plane;

[0006] Taking the convex plane or concave plane formed by the square grids whose rows and columns are both 1 as a reference, for each odd-numbered row, the square grids of each odd-numbered column alternately form a convex plane and a concave plane; for each odd-numbered column, the square grids of each odd-numbered row alternately form a convex plane and a concave plane;

[0007] The square grids of odd rows and even columns and even rows and odd columns serve as connecting surfaces to connect the corresponding convex planes and concave planes.

[0008] Furthermore, the angles formed by the concave and convex planes and the connecting surface are all α, forming a planar hollow sandwich structure.

[0009] Furthermore, in the row or column direction, the angles formed by the concave and convex planes and the connecting surface are both σ; in another corresponding direction, the angle formed by the concave plane and the connecting surface is β, and the angle formed by the convex plane and the connecting surface is γ, β≠γ; forming a curved hollow sandwich structure.

[0010] Furthermore, in the row or column direction, the angles formed by the concave and convex planes and the connecting surface are both σ; in another corresponding direction, the hollow sandwich structure is connected end to end, the angle formed by the concave plane and the connecting surface is β, and the angle formed by the convex plane and the connecting surface is γ, β≠γ; forming a ring-shaped hollow sandwich structure.

[0011] According to the method for manufacturing the hollow sandwich structure of the present invention, the planar hollow sandwich structure is formed in one step by stamping.

[0012] The manufacturing method of the hollow sandwich structure of the present invention is to firstly punch and form the planar hollow sandwich structure according to the angle σ, and then adjust the planar hollow sandwich structure or the ring-shaped hollow sandwich structure through the corresponding mold.

[0013] The pressure-resistant sandwich panel of the present invention comprises the hollow sandwich structure, and the upper and lower sides of the planar hollow sandwich structure are bonded with surface board layers through adhesive layers.

[0014] The pressure-resistant sandwich panel of the present invention comprises the hollow sandwich structure, wherein the upper and lower sides of the curved hollow sandwich structure are bonded with surface plate layers via adhesive layers; the inner and outer sides of the annular hollow sandwich structure are bonded with cylindrical surface plate layers via adhesive layers.

[0015] Furthermore, the convex plane and the concave plane are processed into arc shapes adapted to the surface board layer so that the hollow sandwich structure and the surface board layer can fit perfectly; alternatively, arc grooves are processed into the surface board layer, and then the convex plane and the concave plane are knocked and embedded into the corresponding arc grooves so that the hollow sandwich structure and the surface board layer can fit perfectly.

[0016] Furthermore, array-shaped small pits are knocked out on the convex surface and the concave surface, and the same operation is performed on the surface layer to increase the friction between the hollow sandwich structure and the surface layer.

[0017] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0018] (1) The hollow sandwich structure can be formed into a plane, a curved surface or a ring structure, which has better applicability, for example, it can be used as a sandwich structure of a plane double-layer plate or a sandwich structure of a double-layer cylindrical shell;

[0019] (2) The hollow sandwich structure can further reduce weight. The hollow sandwich structure formed by folding the plane hollow grid can, when applied to sandwich panels, have extremely excellent pressure resistance and impact resistance while being lightweight.

[0020] (3) The hollow sandwich structure has the advantages of simple structure, convenient processing and good economy. The flat hollow sandwich can be stamped once, while the curved or ring-shaped hollow sandwich structure can be trimmed by the corresponding mold after stamping.

[0021] (4) In some working environments with higher temperatures, the hollow sandwich structure has a better heat dissipation effect than the honeycomb structure;

[0022] The present invention has broad application prospects in the fields of submersibles, ships, aerospace, automobiles, construction, etc. For example, it can be used as sandwich structures such as submersible pressure hulls, ship anti-collision systems, aircraft sandwich panels, automobile protective panels, and building walls. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic diagram of the structure of a 5×7 square grid in an embodiment of the present invention;

[0024] Figure 2 Schematic diagram of a 5×7 planar hollow sandwich structure in an embodiment of the present invention;

[0025] Figure 3 yes Figure 2 The main view;

[0026] Figure 4 yes Figure 2 Left view of

[0027] Figure 5 is a schematic structural diagram of a 5×7 flat pressure-resistant sandwich panel in an embodiment of the present invention;

[0028] Figure 6 is a schematic diagram of a ring-shaped hollow sandwich structure in an embodiment of the present invention;

[0029] Figure 7 yes Figure 6 A top view of

[0030] Figure 8 yes Figure 6 The outer contour structure along the axial direction;

[0031] Fig. 9 is a top view of an annular pressure-resistant sandwich plate in an embodiment of the present invention;

[0032] Fig.10 It is a cross-sectional view of the annular hollow sandwich structure after being struck in the cylindrical surface plate layer in the embodiment of the present invention. DETAILED DESCRIPTION

[0033] The present invention will be further described below in conjunction with the accompanying drawings.

[0034] Example 1

[0035] This embodiment 1 provides a planar hollow sandwich structure, comprising a (4n±1)×(4n±1) square grid, wherein n is an integer greater than or equal to 1, and the square grid with even numbers of rows and columns is hollowed out.

[0036] A square grid with rows and columns of 1 bulges upward to form a convex plane, or sinks downward to form a concave plane.

[0037] Taking the convex plane or concave plane formed by the square grids with rows and columns of 1 as a reference, for each odd row, the square grids of each odd column alternately form a convex plane and a concave plane; for each odd column, the square grids of each odd row alternately form a convex plane and a concave plane.

[0038] The square grids of odd rows and even columns and even rows and odd columns serve as connecting surfaces to connect the corresponding convex planes and concave planes.

[0039] The angles formed by the concave and convex planes and the connecting surface are all α, forming a planar hollow sandwich structure.

[0040] A specific example is given below.

[0041] like Figure 1 The 5×7 square grid shown, wherein the square grids at the 2nd row and 2nd column, the 2nd row and 4th column, the 2nd row and 6th column, the 4th row and 2nd column, the 4th row and 4th column and the 4th row and 6th column are hollowed out.

[0042] like Figure 2 As shown, the square grids with rows and columns of 1 are concave downward to form a concave plane. With this as a reference, the 1st row, 3rd, 5th, and 7th columns alternately form a concave plane, a convex plane (the square grids bulge upward), a concave plane, etc.; the 1st, 3rd, 5th, and 7th columns of the 3rd row alternately form a convex plane, a concave plane, a convex plane, etc.; the 1st, 3rd, 5th, and 7th columns of the 5th row alternately form a concave plane, a convex plane, a concave plane, etc. The remaining square grids serve as connecting surfaces, connecting the corresponding convex planes and concave planes. Figure 3 As shown, the angles formed by the concave and convex planes and the connecting surface are all α, thereby forming a 5×7 planar hollow sandwich structure.

[0043] Combination Figure 4 , a 5×7 square grid forms a planar hollow sandwich structure with a length of x, a width of y, and a height of h. Each square grid is the same size and has a side length of a. The following functional relationship can be obtained:

[0044] x=4a+3acos(180°-α)

[0045] y=3a+2acos(180°-α)

[0046] h=asin(180°-α)

[0047] In specific applications, the side length a and angle α of the square grid can be designed according to the size of the planar hollow sandwich structure. An array composed of more square grids can also be used to form a planar hollow sandwich structure to meet actual size requirements.

[0048] In the planar hollow sandwich structure, the concave and convex planes can be reversed, and the technical effect is the same.

[0049] Example 2

[0050] This embodiment 2 provides a method for manufacturing the planar hollow sandwich structure described in embodiment 1, comprising:

[0051] Formed in one step by stamping.

[0052] Example 3

[0053] This embodiment 3 provides a planar pressure-resistant sandwich plate, including the planar hollow sandwich structure described in embodiment 1, wherein the upper and lower sides of the planar hollow sandwich structure are bonded to the surface plate layer by an adhesive layer. The plate layer material, adhesive layer material and sandwich material can be determined according to specific needs.

[0054] The 5×7 planar hollow sandwich structure in Example 1 can form a 5×7 planar pressure-resistant sandwich panel, such as Figure 5 shown.

[0055] Example 4

[0056] like Figures 6 to 8 As shown, this embodiment 4 provides a ring-shaped hollow sandwich structure, including a (4n±1)×(4n±1) square grid, wherein n is an integer greater than or equal to 1, and the square grids with even numbers of rows and columns are hollowed out.

[0057] A square grid with rows and columns of 1 bulges upward to form a convex plane, or sinks downward to form a concave plane.

[0058] Taking the convex plane or concave plane formed by the square grids with rows and columns of 1 as a reference, for each odd row, the square grids of each odd column alternately form a convex plane and a concave plane; for each odd column, the square grids of each odd row alternately form a convex plane and a concave plane.

[0059] The square grids of odd rows and even columns and even rows and odd columns serve as connecting surfaces to connect the corresponding convex planes and concave planes.

[0060] In the row or column direction, the angles formed by the concave and convex planes and the connecting surface are both σ; in the corresponding other direction, the hollow sandwich structure is connected end to end, the angle formed by the concave plane and the connecting surface is β, and the angle formed by the convex plane and the connecting surface is γ, β≠γ; thereby forming a ring-shaped hollow sandwich structure.

[0061] The three angles β, γ and σ can be determined by the size of the annular hollow sandwich structure in practical applications.

[0062] Similar to the plane hollow sandwich structure, the length, thickness and folding angle of the ring-type hollow sandwich structure can be adjusted by adjusting the parameters of the ring-type hollow sandwich structure to adapt to different application scenarios. The folding method is the same as the plane hollow sandwich structure, but the angle is slightly different. The curved hollow sandwich structure is similar to the ring-type hollow sandwich structure, but the ends are not connected, so it will not be described here.

[0063] Example 5

[0064] This embodiment 5 provides a method for manufacturing the annular hollow sandwich structure described in embodiment 4, comprising:

[0065] First, stamping is performed at an angle σ to form a planar hollow sandwich structure;

[0066] In order to make the hollow sandwich structure better fit the cylindrical plate layer, the flat hollow sandwich structure is bent into the required ring structure. Taking the metal hollow sandwich structure as an example, the flat hollow sandwich structure passes through a mold with the same curvature as the plate layer. When passing through the mold, the mold knocks the metal sandwich structure. After completely passing through the mold, a ring-shaped hollow sandwich structure that can completely fit the plate layer is processed.

[0067] The manufacturing method of the curved hollow sandwich structure is similar to that of the ring-shaped hollow sandwich structure, which will not be described in detail here.

[0068] Example 6

[0069] This embodiment 6 provides an annular pressure-resistant sandwich plate, including the annular hollow sandwich structure described in embodiment 4, wherein the inner and outer sides of the annular hollow sandwich structure are bonded with a cylindrical surface plate layer through an adhesive layer. The plate layer material, adhesive layer material and sandwich material can be determined according to specific needs.

[0070] When manufacturing the annular hollow sandwich structure, the convex plane and the concave plane are not limited to a flat square. For example, the convex plane and the concave plane can be processed into an arc shape suitable for the metal plate layer, so that the annular hollow sandwich structure and the surface plate layer are completely fitted, and then the annular hollow sandwich structure and the surface plate layer are bonded, such as Fig. 9 As shown, a completely fitted annular pressure-resistant sandwich panel can be obtained.

[0071] The surface plate layer can also be processed into an arc groove to better fit the annular hollow sandwich structure. After the surface plate layer and the annular hollow sandwich structure are fitted together, the connection between the inner wall of the outer plate layer and the convex plane of the annular hollow sandwich structure is knocked from the inside to the outside, and the connection between the outer wall of the inner plate layer and the concave plane of the annular hollow sandwich structure is knocked from the outside to the inside, such as Fig.10 As shown, this results in a stable sandwich structure that is completely fixed between the inner and outer plies.

[0072] At the same time, before the annular hollow sandwich structure is placed in the inner and outer plate layers, small pits in an array can be knocked out on the convex and concave planes, and the same operation can be performed on the inner wall of the outer plate layer and the outer wall of the inner plate layer. This can greatly increase the friction after the inner and outer plate layers are placed. Then, the connection between the inner wall of the outer plate layer and the convex plane of the annular hollow sandwich structure is knocked from the inside to the outside, and the connection between the outer wall of the inner plate layer and the concave plane of the annular hollow sandwich structure is knocked from the outside to the inside, so as to better ensure that the annular hollow sandwich structure will not loosen.

[0073] The curved pressure-resistant sandwich panel is similar to the ring-shaped pressure-resistant sandwich panel and will not be described in detail here.

Claims

1. A hollow sandwich structure, characterized in that: A square grid of (4n±1)×(4n±1), wherein n is an integer greater than or equal to 1, and the square grids with even numbers of rows and columns are hollowed out; A square grid with rows and columns of 1 bulges upward to form a convex plane, or sinks downward to form a concave plane; Taking the convex plane or concave plane formed by the square grids whose rows and columns are both 1 as a reference, for each odd-numbered row, the square grids of each odd-numbered column alternately form a convex plane and a concave plane; for each odd-numbered column, the square grids of each odd-numbered row alternately form a convex plane and a concave plane; The square grids of odd rows and even columns and even rows and odd columns serve as connecting surfaces to connect the corresponding convex planes and concave planes.

2. The hollow sandwich structure according to claim 1, characterized in that: The angles formed by the concave and convex planes and the connecting surface are all α, forming a planar hollow sandwich structure.

3. The hollow sandwich structure according to claim 1, characterized in that: In the row or column direction, the angles formed by the concave and convex planes and the connecting surface are both σ; in the other corresponding direction, the angle formed by the concave plane and the connecting surface is β, and the angle formed by the convex plane and the connecting surface is γ, β≠γ; forming a curved hollow sandwich structure.

4. The hollow sandwich structure according to claim 1, characterized in that: In the row or column direction, the angles formed by the concave and convex planes and the connecting surface are both σ; in the corresponding other direction, the hollow sandwich structure is connected end to end, the angle formed by the concave plane and the connecting surface is β, and the angle formed by the convex plane and the connecting surface is γ, β≠γ; forming a ring-shaped hollow sandwich structure.

5. The method for manufacturing a hollow sandwich structure according to claim 2, characterized in that: The planar hollow sandwich structure is formed in one step by stamping.

6. The method for manufacturing a hollow sandwich structure according to claim 3 or 4, characterized in that: First, it is punched into a planar hollow sandwich structure according to the angle σ, and then adjusted into a curved hollow sandwich structure or a ring-shaped hollow sandwich structure through a corresponding mold.

7. A pressure-resistant sandwich panel, characterized in that: It comprises the hollow sandwich structure as claimed in claim 2, wherein the upper and lower sides of the planar hollow sandwich structure are bonded with surface board layers via adhesive layers.

8. A pressure-resistant sandwich panel, characterized in that: It comprises the hollow sandwich structure as claimed in claim 3 or 4, wherein the upper and lower sides of the curved hollow sandwich structure are bonded with surface plate layers via adhesive layers; the inner and outer sides of the annular hollow sandwich structure are bonded with cylindrical surface plate layers via adhesive layers.

9. The pressure-resistant sandwich panel according to claim 8, characterized in that: The convex plane and the concave plane are processed into arc shapes adapted to the surface board layer so that the hollow sandwich structure and the surface board layer can be fully fitted; alternatively, arc grooves are processed into the surface board layer, and then the convex plane and the concave plane are knocked and embedded into the corresponding arc grooves so that the hollow sandwich structure and the surface board layer can be fully fitted.

10. The pressure-resistant sandwich panel according to claim 9, characterized in that: An array of small pits are knocked out on the convex and concave surfaces, and the same operation is performed on the surface layer to increase the friction between the hollow sandwich structure and the surface layer.

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