DE202014002924U1 - Core for sandwich components - Google Patents

Abstract

Core for sandwich components, the core (1) comprising at least two folded partial layers (2) which at least partially interlock and each have a thickness (x1), and the thickness of the core (X) in the region of interlocking sections of the partial layers ( 2) is less than the sum of the thicknesses (x1) of the partial layers (2).

Description

The invention relates to a core for sandwich components.

Multilayer lightweight structures comprising a core disposed between two cover layers are commonly referred to as sandwich structures or sandwich components and are known in the art. They are characterized by a particularly low weight and at the same time relatively high strength and have therefore found a wide distribution in numerous fields of application. It is known to use special cores for the production of sandwich components. For example, materials such as paper, cardboard, plastic, foam or wood are used for these cores. In addition, the cores can be shaped differently depending on the application, are known for. B. wave structures of corrugated cardboard or honeycomb core structures. The disadvantage of known sandwich panels is that they are only slightly deformable and do not allow the production of highly curved moldings. Even relatively flexible corrugated board with an S-shaped core are flexible deformable in one direction only in the direction of the waves, whereas they are stiff in the direction transverse to the waveform.

The object of the present invention is to reduce or avoid one or more disadvantages of the prior art. In particular, it is an object of the present invention to provide a core for sandwich components, with which stable, yet flexibly deformable sandwich components can be produced.

This object is achieved by a core for sandwich components according to claim 1.

According to the invention, a core for sandwich components is proposed, which comprises at least two folded partial layers, wherein the folded partial layers at least partially intermesh.

Further details, features and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the drawings and illustrated figures. Showing:

1 a schematic representation of a core for a sandwich component in a perspective view;

2 a schematic representation of two partial layers of a core for a sandwich component in a perspective view, and the schematic representation of a way to arrange these partial layers so that they interlock, also shown in perspective;

3 a schematic representation of a pair of cells in a perspective view and a schematic representation of a possible folding pattern in plan view, with which such a pair of cells can be folded, and a schematic representation of the individual parts of the folding pattern in plan view;

4 a schematic representation of a sandwich component with a core in a perspective view;

5 a schematic representation of possible folding pattern in different embodiments in plan view;

6 a schematic representation of a folding pattern in plan view comprising a plurality of adjacent cell pairs;

7 a schematic representation of two partial layers (of a core) in profile section;

8th a schematic representation of two partial layers, which are interconnected and form a larger partial position;

9 a schematic representation of four partial layers, which are interconnected and form a larger partial layer;

10 a schematic representation of two larger partial layers, each comprising four smaller partial layers, and form a core;

11 a schematic representation of a partial layer, which is connected to a core comprising two partial layers;

12 a schematic representation of a partial layer, which is connected to a core comprising two partial layers;

13 a schematic representation of two partial layers, which are interconnected and form a self-contained core;

14 a schematic representation of three partial layers, which are connected to each other so that they form a double hollow chamber core;

15 a schematic representation of three partial layers, which are connected together so that they form a T-core;

16 a schematic representation of a partial layer, which is associated with it, that it forms a T-core;

17 a schematic representation of four partial layers, which are interconnected so that they form a cross-core;

18 a schematic representation of a partial layer, which is associated with it so that it forms a cross-core;

19 a schematic representation of five partial layers; which are connected to each other so that they form a cross hollow core; and

20 a schematic representation of four partial layers, which are connected together so that they form a double T-core.

1 schematically shows a possible structure of a core 1 for a sandwich component 4 , The core 1 may include a material such as paper, cardboard, wood, metal z. As sheets, plastics z. As thermoplastics, thermosets, elastomers, resins, natural fiber fabrics, fiber materials, such. As glass, metal, basalt, casein, ceramic, carbon, aramid, acrylic, polyethylene, polypropylene, polyester, polyamide fibers, nonwoven materials, scrims, films, for. As metal or glass foils, electrically conductive materials and / or combinations thereof. The material of the core 1 can be perforated.

The material of the core 1 may be at least partially treated or coated, for example it may be impregnated. Suitable impregnating agents are known in the art, for. For example, these impregnating agents may be manufactured on paraffin, wax, synthetic resin or silicone bases.

The material of the core 1 has a thickness of 0.05 to 1000 mm, preferably 0.10 to 100 mm, particularly preferably 0.5 to 50 mm.

The core 1 has a total thickness of 1 to 10,000 mm, preferably 5 to 1000 mm, particularly preferably 10 to 100 mm.

The core of the invention 1 is suitable for lightweight structures in sandwich construction, which should be both stable and malleable. The folded three-dimensional structure is the entire core 1 extremely flexibly deformable and can be easily adapted to shaping surfaces. In this way, even complicated geometries such as balls can be produced in a simple manner.

2 shows an example of two folded partial layers 2 a core 1 for a sandwich component 4 , The core 1 includes at least two folded partial layers 2 which at least partially intermesh and which each have a thickness x1. The thickness of the core X is in the range of intermeshing portions of the partial layers 2 less than the sum of the thicknesses x1 of the partial layers 2 , Interlocking sections are substantially parallel to each other. The thickness of the partial layers 2 can be dimensioned transversely to its propagation direction. The partial days 2 interlock in such a way that the folding of the diagonal and the rhombic structure of the one part position 2 is formed in the direction of the core center and that the folding of the diagonal and the rhombic structure of the other part position 2 is also formed in the direction of the center of the core. In other words, the partial layers are effective 2 in opposite directions, forming a folded core in this way 1 out. Preferably, the partial layers 2 inserted into each other in opposite directions. Due to the repeating folding structure, cores can 1 be enlarged endlessly by surface in- or juxtaposition. Furthermore, the three-dimensional and flexibly deformable folding structure offers the possibility of one or more partial layers 2 to cores 1 to arrange, which may have different cross-sections ("profile cores"). The partial days 2 may be parallel, but also trapezoidal and / or conical to each other.

The partial days 2 can be connected together at one or more joints, for example by gluing or welding, whereby stable joints can be created.

It is possible, a partial position 2 to bond with a cover layer to generate a single-layer molded part.

Although in the presentation of 1 and 2 two partial days 2 are arranged one above the other, the core of the invention 1 can train, the core 1 in other examples, more than two folded superimposed partial layers 2 include.

The partial days 2 can be made of a material selected from the group of paper, cardboard, cardboard, fabric and fleece. Furthermore, the partial layers 2 also be constructed of composite materials. The materials of the partial layers 2 can have special properties, eg. B. they can be electrically conductive.

Between the partial days 2 There is a gap due to the interlocking of the folded partial layers 2 arises and which the later cavities in the from the core 1 shapeable sandwich structure 4 formed. These Gaps can be filled at least partially.

The partial days 2 comprise at least one folded cell pair 3 , Be multiple cell pairs 3 arranged next to each other, results in a 6 schematically illustrated pattern, which is infinitely expandable by joining other cell pairs 3 ,

In a partial position 2 lie single or all folded cell pairs 3 preferably at least partially against each other. The cell pairs 3 may be glued together or otherwise secured together.

3 shows a perspective view of a cell pair 3 , To the way of folding the cell pair 3 is in 3 also a schematic representation of a possible folding pattern of the cell pair 3 shown in plan view. This folding pattern is also illustrated by means of its individual parts, which are denoted by the reference numerals a to j and in stronger lines for the sake of simplicity. Taking the individual parts a to j together, this results in 3 centrally shown folding pattern.

The cell pair 3 has a rectangular base area a, wherein the base area a two rectangular and arranged in a first direction juxtaposed subunits b1, b2 and the subunits b1, b2 each include two subunits c, d or e, f, which are arranged side by side in a second direction are. The first and second directions are perpendicular to each other.

One of the two subunits b1 or b2 is folded so as to form two diagonal g, h, and the other subunit b1 or b2 is folded to form a diamond pattern i.

The cell pair 3 is folded such that between the two subunits b1 and b2 a crease edge j, between the subunits c, d a kink edge k, between the subunits e, f a crease edge l is formed and the kink edges j, k, l in the direction of a major surface A. or B are directed and that the two diagonal g, h and the diamond structure i are directed in the direction of the other major surface A or B. In other words, the kink edges j, k, l are folded in exactly the opposite direction as the two diagonals g, h and the diamond structure i.

A schematic representation of possible folding patterns of a cell pair 3 in different embodiments in plan view is in 5 shown. In the first illustrated embodiment, the folding of the subunits b1 and b2 of the cell pair results 3 of four isosceles triangles and eight right triangles, the area of each of these right triangles being only half the area of each isosceles triangle. In other embodiments, the triangles may also be acute-angled or obtuse-angled ( 5 Middle and bottom). Multiple contiguous folding patterns of the same cell pairs 3 yield a folding pattern 6 ,

4 shows schematically a sandwich component 4 with a core 1 , which is arranged between two cover layers. To achieve high flexibility is the core 1 of the sandwich component 4 preferably constructed in a folding structure. The fold structure according to the invention is particularly preferred. The sandwich component 4 comprises at least two outer layers and a core arranged between these outer layers. The core 1 is in the in 4 folded example and includes two folded partial layers 2 , which (as in 2 shown) are arranged so that they interlock.

The cover layers may be made of a material selected from the group consisting of paper, cardboard, metal, glass, stone, concrete, cement, ceramics and plastics and / or combinations thereof. Furthermore, the cover layers can also be constructed of composite materials. The materials of the cover layers can be reinforced. The cover layers may be at least partially treated, for example impregnated.

The bond between the core 1 and the cover layers in the sandwich component 4 can be prepared by known joining techniques, for example by adhesive bonds, welding, brazing, mechanical bonding, z. B. by screws, rivets or snap connections.

The sandwich component 4 can be used in a wide variety of applications, such as aircraft, truck, rail vehicle, watercraft, container, wind turbine, furniture and house construction.

The invention further includes a method for producing a folded core 1 for sandwich components 4 , The production of the core 1 can be done manually or mechanically by, for example, folding, bending, punching and / or embossing techniques. That for the folding of the core 1 used folding pattern can by various techniques on the core 1 used material are applied, for. B. drawn, printed, punched.

LIST OF REFERENCE NUMBERS

1

core

2

nests

3

cell pair

a

rectangular base of a cell pair

b1 + b2

rectangular subunits of a

c + d

rectangular subunits (from b)

e + f

rectangular subunits (from b)

g + h

diagonal

i

diamond texture

j

Buckling edge between the subunits b1 + b2

k

Buckling edge between the subunits c + d

l

Buckling edge between the subunits e + f

A + B

main areas

X

Thickness of the core

x1

Thickness of the partial layers

Claims (10)

Core for sandwich components, the core ( 1 ) at least two folded partial layers ( 2 ), which at least partially intermesh and each have a thickness (x1), and wherein the thickness of the core (X) in the region of intermeshing portions of the partial layers ( 2 ) is less than the sum of the thicknesses (x1) of the partial layers ( 2 ). Core according to claim 1, characterized in that the folded partial layers ( 2 ) at least one folded cell pair ( 3 ). Core according to claim 1 or 2, characterized in that the cell pair ( 3 ) has a rectangular base area (a), the base area (a) having two rectangular subunits (b1, b2) arranged side by side in a first direction, and the subunits (b1, b2) each having two subunits (c, d or e, f) juxtaposed in a second direction, the first and second directions being perpendicular to each other. Core according to one of claims 1 to 3, characterized in that one of the two subunits (b1 or b2) is folded so that it forms two diagonal (g, h) and the other subunit (b1 or b2) is folded such that she forms a diamond structure (i). Core according to one of claims 1 to 4, characterized in that the cell pair ( 3 ) is folded such that between the two subunits (b1 and b2) a buckling edge (j), between the subunits (c, d) a buckling edge (k), between the subunits (e, f) a buckling edge (l) is formed and the kink edges (j, k, l) are directed in the direction of a major surface (A or B), and that the two diagonals (g, h) and the diamond structure (i) are directed in the direction of the other major surface (A or B) , Core according to one of claims 1 to 5, characterized in that the partial layers mesh in such a way that the folding of the diagonal and the rhombic structure of a partial layer is formed in the direction of the core center and that the folding of the diagonal and the rhombic structure of the other partial layer also in the direction of the core center is formed. Core according to one of claims 1 to 6, characterized in that the core ( 1 ) has a total thickness of 1 to 10,000 mm, preferably 5 to 1000 mm, particularly preferably 10 to 100 mm. Core according to one of claims 1 to 7, characterized in that the partial layers ( 2 ) consist of a material selected from the group of paper, cardboard, cardboard, plastics, scrim, sheet metal, fabric, non-woven and / or combinations thereof. Sandwich component ( 4 ) of at least two outer layers and a core arranged between these layers according to one of claims 1 to 8. Sandwich component ( 4 ) according to claim 9, wherein the cover layers are made of a material selected from the group consisting of paper, cardboard, metal, glass, stone, concrete, cement, ceramics, plastics and / or combinations thereof.

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