EP0839088B1 - Folded-sheet honeycomb structure - Google Patents

Abstract

A folded honeycomb, in particular a sandwich core layer, with walls (22) which are arranged in a rectangular or hexagonal configuration and which are perpendicular to the cover layers, for lightweight structures which are formed from a flat body of metal, plastic material, cloth, fiber composite material or paper by the production of cuts and by folding to constitute rectangular corrugations. The folded honeycomb has relatively large connecting surfaces (13, 16) for connection to the cover layers.

Description

The invention relates to folded honeycombs from a Plurality of cells, on method of making the Folded honeycombs and on applications of such folded honeycombs.

Sandwich core layers are usually made from honeycombs manufactured, the cells of which are equilateral hexagons form. The honeycomb layer is provided with cover layers, which are glued to the edges of the honeycomb webs. In the Practice the honeycomb by cutting off one Honeycomb block won. The sandwich composite is the Critical connection of the honeycomb edges with the cover layers, which is why you have relatively thick layers of adhesive for embedding the honeycomb edges used and the viscosity of the adhesive closely monitored.

There are also honeycombs to the cell walls integral cover layer parts known (US-A-4 197 341). However, such honeycombs must be made from individual strips of which two strips form a Row of cells are put together, which is a precise Manufacture of the cell row elements requires.

It is also known to have folded honeycombs from a flat surface Production of sheet material to be cut (WO-94/02311 = PCT / US93 / 06872). One embodiment of the folding honeycomb is with Provide pads for cover layers, which however across cell wall gaps between large, octagonal cells and smaller, hexagonal cells. The other Embodiment consistently includes hexagonal cells, however no pads for top layers.

The invention has for its object a Specify folded honeycomb with cells of the same type, made of flat Cutting sheet material is folded and sufficient offers large connection surfaces to cover layers.

The invention is defined in the claims.

Externally, the new folding honeycomb differs from   the folded honeycomb cut from the block in that it is transverse to there are bridging sections running along the honeycomb walls, form the connection surfaces for cover layers. If the Folded honeycomb is therefore used as a sandwich core layer, can be a high drum peel strength of the top layer against the sandwich core layer.

Since the folded honeycomb was oriented differently, vertical walls (i.e. walls that are perpendicular to each other) it is parallel to the layer in every direction relatively rigid and resistant to shear.

The connection surfaces are as bridging parts formed, which integrally integrates the cell walls connect and so for an additional stiffening of the Fold the honeycomb across the cell walls.

The bridging parts are in the flat blank delimited by cuts and if necessary by fold lines. It is possible to make U-shaped cuts and the flaps formed thereby in whole or in part as To use pads.

It is also possible to use wedge-shaped honeycombs or generally produce with height profile. The stripe-shaped Parts are getting wider and narrower made, and the boundary cuts of the strip-shaped Areas are curved or along route curves executed.

Before the touching wave crests and Wave sinks of the half honeycomb waves permanently with each other connected, it is possible to fold the honeycomb in itself move or distort, if necessary to adapt to curved surfaces. This form will then by establishing the permanent connection of the wave crests and wave sinks frozen to a certain extent. In this way bowl-like folded honeycombs can be produced have a certain self-bearing capacity. Such folded honeycombs can be processed into sandwich structure molded parts The honeycomb can also be used in crash structures.  

The web material is used to manufacture the folding honeycomb with cuts and folded, what by a Rolling process is feasible. Is inexpensive to manufacture therefore to be expected. With ordinary paper or cardboard as A folding honeycomb is therefore used as the starting material considered as packaging material.

Fig. 1

einen ebenen Zuschnitt mit Faltlinien und U-förmigen Schnitten,

Fig. 2

eine Rechteckwelle,

Fig. 3

die Rechteckwelle mit Schnittmuster,

Fig. 4

eine Faltwabe in perspektivischer Darstellung,

Fig. 5

eine Rechteck-Kreuz-Faltwabe,

Fig. 6

einen weiteren ebenen Zuschnitt mit Faltlinien und U-förmigen Einschnitten,

Fig. 7

eine Faltwabe in perspektivischer Darstellung, erhältlich aus dem ebenen Zuschnitt der Fig. 6,

Fig. 8

eine schematische Darstellung einer Rechteck-Falt-Wabe,

Fig. 9

nach Expansion sowie

Fig. 10

nach Kontraktion der Waben nach Fig. 8, ferner

Fig. 11

mit Stegfaltung;

Fig. 12

eine impulsförmige Rechteckwelle,

Fig. 13

die impulsförmige Rechteckwelle mit Schnittmuster,

Fig. 14

eine Rechteck-Kreuz-Faltwabe, in perspektivischer Darstellung, gemäß Fig. 12, 13 hergestellt,

Fig. 15

einen weiteren ebenen Zuschnitt mit Faltlinien und Einschnitten,

Fig. 16

eine erste Faltung des ebenen Zuschnitts nach Fig. 15,

Fig. 17

eine weitere Faltung des Zuschnitts,

Fig. 18

eine perspektivische Darstellung einer Einzelheit,

Fig. 19

eine Faltwabe, erhältlich aus dem Zuschnitt der Fig. 15;

Fig. 20

einen weiteren ebenen Zuschnitt mit Faltlinien und Ausschnitten,

Fig. 21

einen Zwischenzustand bei der Herstellung,

Fig. 22

eine hexagonale Faltwabe, gemäß Fig. 20, 21 hergestellt;

Fig. 23

einen weiteren ebenen Zuschnitt mit Faltlinien und Einschnitten,

Fig. 24

einen vergrößerten Abschnitt einer Faltwabe, die aus dem Material der Fig. 23 hergestellt werden ist;

Fig. 25

eine abgewandelte Faltwabe in vergrößerter perspektivischer Ansicht;

Fig. 26

eine vergrößerte perspektivische Ansicht einer weiteren Faltwabe aus abgewandeltem Material;

Fig. 27

einen Zuschnitt für keilförmige Waben,

Fig. 28

eine vergrößerte perspektivische Darstellung einer Faltwabe, hergestellt aus dem Material der Fig. 27;

Fig. 29

einen Zuschnitt für gekrümmte Waben,

Fig. 30

eine perspektivische Ansicht einer gekrümmten Faltwabe, hergestellt aus dem Material der Fig. 29,

Fig. 31

einen weiteren ebenen Zuchnitt mit Faltlinien und Einschnitten

Fig. 32

einen Zwischenzustand bei der Herstellung,

Fig. 33

eine hexagonale Faltwabe, gemäß Fig. 31, 32 hergestellt.

Embodiments of the invention are described with reference to the drawing. It shows:

Fig. 1

a flat cut with fold lines and U-shaped cuts,

Fig. 2

a square wave,

Fig. 3

the square wave with pattern,

Fig. 4

a folding honeycomb in perspective,

Fig. 5

a rectangular cross folding honeycomb,

Fig. 6

another flat cut with fold lines and U-shaped incisions,

Fig. 7

6 shows a folded honeycomb in perspective, obtainable from the flat blank of FIG. 6,

Fig. 8

1 shows a schematic representation of a rectangular folding honeycomb,

Fig. 9

after expansion as well

Fig. 10

after contraction of the honeycomb according to Fig. 8, further

Fig. 11

with web folding;

Fig. 12

a pulse-shaped square wave,

Fig. 13

the pulse-shaped square wave with a pattern,

Fig. 14

a rectangular cross-folded honeycomb, made in perspective, according to FIGS. 12, 13,

Fig. 15

another flat cut with fold lines and incisions,

Fig. 16

15 a first folding of the flat blank according to FIG. 15,

Fig. 17

a further folding of the blank,

Fig. 18

a perspective view of a detail,

Fig. 19

a folding honeycomb, obtainable from the blank of FIG. 15;

Fig. 20

another flat cut with fold lines and cutouts,

Fig. 21

an intermediate state of manufacture,

Fig. 22

a hexagonal folded honeycomb, produced according to Fig. 20, 21;

Fig. 23

another flat cut with fold lines and incisions,

Fig. 24

an enlarged portion of a folded honeycomb made from the material of Fig. 23;

Fig. 25

a modified folded honeycomb in an enlarged perspective view;

Fig. 26

an enlarged perspective view of another folded honeycomb made of modified material;

Fig. 27

a blank for wedge-shaped honeycombs,

Fig. 28

an enlarged perspective view of a folded honeycomb, made of the material of FIG. 27;

Fig. 29

a blank for curved honeycombs,

Fig. 30

3 shows a perspective view of a curved folded honeycomb, made from the material of FIG. 29,

Fig. 31

another flat cut with fold lines and incisions

Fig. 32

an intermediate state of manufacture,

Fig. 33

a hexagonal folded honeycomb, according to FIGS. 31, 32.

1 shows a flat sheet of thin sheet metal, Plastic, fabric, fiber composite material (with carbon, Aramid or glass fibers) or fiber-reinforced paper (Nomex® paper), which after folding a sandwich core layer forms according to the invention. For illustrative purposes, the Folded lines drawn in dashed lines in the web, which in the Folded during processing. Are in detail continuous, horizontal fold lines 1, 2, 3, 4 and broken, vertical fold lines 5 and others Fold lines 7, 8 indicated. To prepare the Processing can still strips of adhesive or solder 19 aligned to fold lines 5 on both sides of the web   be attached. You can also go through the folds Prepare embossing lines. One also sees rows of U-shaped ones Cuts 9, the legs 11, 12 with the horizontal fold lines 4, 1 or 2, 3 coincide, while the base 10 of the U is parallel to the fold lines 5, 7 extends. These U-cuts 9 can be before, during or generated after folding around fold lines 1, 2, 3, 4 stamping is preferred. The U-cuts 9 delimit layer lobes that emerge from the path plane in the sandwich core layer to be formed is bent into it should. As can be seen, the ends of the legs 11 fall 12 together with the fold lines 5, whereby for adjacent base 10 each have a pad 13 or 16 is formed, the meaning of which will be explained later becomes. The layered lobes within the respective U-shaped Sections 9 have sections 14, 15 and sections 17, 18 on, separated by the fold lines 7 and 8 are. The sections 14, 17 are for the formation of web walls provided and are initially lobed, which is why this Sections are also referred to as web tabs 14, 17.

Fig. 2 shows a square wave, as it is from a Part of the web of FIG. 1 can be produced. As Tools for this are punching or rolling, which the Gradually pull in the material web without it because of the Path shortening for tearing the material comes. How between fold lines 1 to 4 Wave crests 20, troughs 21 and ridges 22 educated. In Fig. 3, the U-shaped are still in the square wave Cuts 9 and the fold lines 7, 8 drawn in, from which it follows that the web surfaces 22 in the Sandwich core layer remain unchanged while the Wave crests 20 in the pads 13 and the Web flap 14 with tab surfaces 15 and the trough surfaces 21 with the connecting surfaces 16 and the web flaps 17 with Tab surfaces 18 are subdivided.

To form the folded honeycomb shown in FIG. 4 the sections 14 + 15 around the fold lines 5 down   and section 15 bent upward about fold line 7. This leaves the original wave crest surface 20 only the pad 13 in the plane of the Wellenberg. With regard to the trough surfaces 21 proceed similarly. Sections 17 + 18 are going up folded and section 18 then into the horizontal bent back. As a tool for this bending and Folding processes come with ram dies with the upper tool and lower tool into consideration. Are on the upper tool finger-like bending plungers are present, which the tabs 14, 15 bend down until the lower die is reached which the tab 15 is bent into the horizontal. At the Lower tools are also finger-like bending plungers provided that the tabs 17, 18 bend up to the upper die is reached where the tab 18 in the Is bent horizontally. Fill the finger-like pestles rooms 23 and 24, which are between the web walls 22 and 14 or 22 and 17 are formed before being withdrawn become. By folding and bending they come Cut edges 11 and 12 in contact with the web surface 22 and can be connected to it by suitable measures be, for example by means of adhesive or Strips of solder material 19. As can be seen, the folded honeycomb offers larger pads 13 and 16 and tab surfaces 15, 18 for connecting cover layers, so that a shear resistant Composite is easy to manufacture.

In the embodiment of FIG. 4, the Pads 13 and the tabs 18 after different pages while you are also the same Folding side can choose, as shown in Fig. 5 is. In this case, the tabs 15, 18 are initially not bent by the ram, rather this only takes place in a separate step when the ram is withdrawn are. Alternatively, different sets of Bending rams (also swiveling) can be used to the to generate the illustrated folding structure. The honeycomb cells form the differently oriented, vertical walls   from the web surfaces 22 and the web flaps 14, 17. Both on there is the top as well as the bottom Pads 13, 18 and 15, 16.

If the cut edges 11, 12 not with them touching web walls 22 by gluing, soldering or welding connected (bonded), there is something decreased shear rigidity of the sandwich structure that from the sandwich core layer and the bonded cover layers consists. This low level is sufficient for some applications Stiffness. The cut edges 11, 12 are preferably on bonded to the web walls for maximum shear rigidity and maintain shear strength.

Fig. 6 shows a modification of the cut and Folding pattern compared to Fig. 1. Instead of a single vertical folding line sheet 5 for the vertical web flaps 14, 17 there are now two shifted against each other Folded line sheets 5 and 6. As can be seen, the U-shaped ones Cuts 9 from row to row against each other transferred. In modification of Fig. 1 and in accordance with Fig. 3, the U-shaped cuts 9 are open to the left, i.e. fold line 5 or 6 is always to the left of the corresponding one U-shaped section 9 arranged. This represents one Possibility of variation in the manufacture of the honeycomb Can have meaning.

Based on the cutting and folding pattern of FIG. 6 the folding honeycomb according to FIG. 7 has been produced. Are there the tabs 15 or 18, the finger-like ram in Paths would have been put on afterwards.

A top view of the honeycomb is shown in FIG. 8 shown. The web walls 22 can be wavy deform, either by pulling the Rectangular folding honeycomb structure or by rows Compressing the folded honeycomb structure. After an expansion a honeycomb-like pattern is obtained, as in FIG. 9 shown. After contraction you get one Fish band pattern as shown in Fig. 10. In the Honeycomb shape reduces the honeycomb weight. In the   Fish tape shape gives it more flexibility, namely after both surface directions. This honeycomb shape is therefore for Parts with double curvature are particularly suitable. It understands yourself that depending on the requirements through expansion and Contraction different cell sizes, densities and Can achieve thicknesses for the sandwich cores to be produced.

As FIG. 11 shows, the web walls 22 can also be used Dislocations 25, 26 are folded. This hugs you Areas of the web walls 22 to the edge areas of the web walls 14, 17 so that there is a flat connection between them vertical wall walls.

There are also ways of increasing the size Interfaces between the cover layers and the sandwich core layer, by placing edge strip surfaces on the upper and creates lower cut edges of the web walls 22.

One of these options is the U-shaped Cuts 9 as in Fig. 6, bottom line, to execute, i.e. with an acute angle between the base 10 and the respective leg 11, 12 so that triangular surfaces 27th from the wave crests 20 or the troughs 21 stand still as connecting surfaces for the cover layers can be used. It is understood that the web walls 22 on the somewhat tapering web wall regions 14, 17 can be deformed in order to along the adhesive, soldering or Welds 19 to be connected (bonded) to them.

Another possibility opens up at Use of fabric as the material of the folded honeycomb. Tissue leaves to a certain extent deform in the tissue plane, so that at the upper and lower cutting edges 11, 12 edge bends can be generated by the impregnation material of the Tissue can be fixed.

If fold lines 1 and 4 and 2 and 3 are not parallel sandwich layers are obtained varying thickness. The cuts 9 are the adapted to different thicknesses of the core layer. If necessary, you can get the structure obtained on the stretch the thicker side and on the thinner side   compress to get even width.

a) Eine Bahn aus dem vorgesehenen Material wird bereitgestellt;

b) U-förmige Schnitte 9 werden in Reihen angebracht, um Steglappen zu bilden, die voneinander durch Anschlußflächen 13, 16 getrennt sind;

c) die Bahn wird in Rechteckwellen gefaltet, um Wellenbergflächen 20, Wellentalflächen 21 und Stegflächen 22 zu bilden;

d) die Steglappen 14, 17 werden aus der jeweiligen Ebene des Wellenberges bzw. Wellentals herausgefaltet, wobei die Anschlußflächen 13, 16 in diesen Ebenen verbleiben. Zur Bildung weiterer Laschen- oder Anschlußflächen 15, 18 werden die freien Enden der Steglappen umgebogen.

e) Die Schnittkanten 11, 12 werden mit den Stegflächen 22 fest verbunden (gebondet). Das Verbindungsverfahren richtet sich nach dem verwendeten Material der ebenen Bahn, aus der die Sandwichkernschicht besteht. Es kommt Kleben, Löten und Schweißen in Betracht.

A combined rolling and punching process with interlocking steps can be used to manufacture the folding honeycomb. The following steps can be considered when producing the sandwich core layer with bonded cutting edges:

a) A web of the intended material is provided;

b) U-shaped cuts 9 are made in rows to form web flaps which are separated from one another by connecting surfaces 13, 16;

c) the web is folded into rectangular waves to form wave crest surfaces 20, trough surfaces 21 and web surfaces 22;

d) the web flaps 14, 17 are folded out of the respective plane of the wave crest or wave valley, the connecting surfaces 13, 16 remaining in these planes. To form further tabs or connecting surfaces 15, 18, the free ends of the web flaps are bent over.

e) The cut edges 11, 12 are firmly connected (bonded) to the web surfaces 22. The connection process depends on the material used for the flat web from which the sandwich core layer is made. Gluing, soldering and welding are possible.

Fig. 12 shows a limit shape of a square wave, the assumes an impulsive character. The wave crest 20 is extremely narrow, i.e. the fold lines 2, 3 are fused together. Accordingly, only areas of the Provide trough surface 21 with U cuts, as in FIG. 13 indicated. After the web flaps are unfolded, the in Fig. 14 structure shown.

Fig. 15 shows another flat track with cut and Folding pattern. There are horizontal fold lines 31, 32, 33, 34 and vertical fold lines 35 and 36 provided a Form a grid. There are also two staggered Crowds of meandering incisions 37 and 39, the each a central section 40 and two lateral   Have sections 41, 42. The middle section 40 runs in the middle of the neighboring lines 35, 36. As a result, between the horizontal fold lines 32, 33 Pads 43 and 45 are formed while between the Fold lines 34 and 31 pads 46 and 48 are formed become. In the narrower strip 55 and 57 between the Lines 35 and 36 there are still fields 44 that are part of the We will form web walls, as will be described. Between The folds of fold lines 35 and 36 are also wider Strips 56 and 58, which are divided into square fields 50, 51, 52 are divided.

The web shown in Fig. 15 becomes zigzag folded as shown in Fig. 16. The wider stripes 56, 58 are around the dimension of the narrower strips 55, 57 offset against each other and overlap each other around this Measure.

In a further step, the folding structure of the 16 transversely to the strips around the fold lines 31, 32, 33, 34 folded in a wave shape, with rectangular waves in the final state while maintaining the covering structure according to FIG. 16 be generated. The structure of Fig. 17 then becomes pulled apart, twisting around the folded edges come about, which lead to the cutting edges 41, 42 vertically and the cutting edges 40 horizontally in the Sandwich core layer are aligned. The edges 41, 42 come into contact with fields 50, 51, 52 and can be done with these by gluing, soldering or welding get connected. By moving the structure closer together also a certain surface coverage of web areas the fields 44 and 52 are achieved, thereby the quality of Connection can be improved.

18 is a perspective view of a Section from the sandwich core layer in one state immediately before the surfaces reach their final location take, but something for illustration purposes pulled apart. In practice, the one shown is Structure compressed, whereby the fields 50, 52, 51, 52, 50   etc. belong to web walls in the form of a square wave and the fields 44 are perpendicular and aligned with the web walls 52 are aligned. Such areas are therefore together connected. This is shown in Fig. 19, which is a view points to the sandwich core layer from above.

The sandwich core layer consists of narrower and wider strips 55, 56, 57, 58, which are at least along the Folded edges 36 at the areas 43 and the folded edges 32 or 34 related to fields 44. The narrower Stripes 55, 57 form square waves perpendicular to the Sandwich core layer plane, and the wider strips 56, 58 form square waves in this sandwich core layer. Here represent surfaces 43 wave crests and surfaces 46 Corrugated valleys of strip 55, to which, however, the Surfaces 48 as wave crests and surfaces 45 as Added troughs of the neighboring strip 57 to one connecting strip 59 on the top (FIG. 19) with the arranged surfaces 43, 48 and an underside Terminal strip 60 also arranged with offset Form surfaces 45, 46. The edges 44 of the square waves the narrower strips 55 and 57 and the flanks 52 of the Square waves of the wider strips 56, 58 are in the Sandwich core layer and form web walls or parts of Web walls.

The hexagonal folded honeycombs described below become flat or flat bodies as before manufactured, for example thin sheet metal, Plastic film, fabric, sheet-like bevel composite (with carbon, aramid or glass fibers) or fiber-reinforced Paper (Nomex® paper), but it also becomes normal paper or cardboard considered. The flat material is with incisions and then serves as Starting material for folding.

Fig. 20 shows a flat trajectory with periods of horizontal fold lines 1, 2, 3, 4 and periods of vertical fold lines 5, 6, 7, 8. The fold points can be prepared by embossing lines. Between the fold lines   2 and 3 and 4 and 1 cuts 9 are attached, which in 1 a rectangular area cutting out. The cuts 9 can be slightly in the direction the fold lines 5 and 8 or 6 and 7 may be extended. Such cuts can be made by punching.

Between fold lines 2 and 3, interrupted, strip-shaped areas 20 formed next to the already cuts 9 still mentioned bridging sections 13 included, and between fold lines 4 and 1 interrupted, strip-shaped areas 21 formed in addition to the notches 9, bridging sections 16 contain. Between the broken, stripe-shaped Areas 20 and 21 are continuous strip-shaped Areas 22 defined by the periodic fold lines 5, 6, 7 and 8 are interspersed. As can be seen, they are strip-shaped areas 22 over the Bridging sections 13 and 16 connected to each other, see above that the material provided for folding from a connected flat body exists.

20 can be divided into two directions perpendicular to each other are folded, namely square waves can be generated, the strip-shaped areas 20 the wave crests that strip-shaped areas 21 the troughs and the strip-shaped areas 22 which form wave flanks. The Curl in the direction perpendicular to it is by bending or partially folded around fold lines 5 through 8, what is called "wrinkling" here. It will Trapezoidal waves are generated which are called "half honeycomb waves Wave crests and wave sinks "are referred to.

21 shows an intermediate shape with half honeycomb waves from three strip-shaped areas 22. As can be seen, 20 is pleated so that the Bridging sections 13 are aligned with the wave crests, while the bridging sections 16 to the shaft sinks swear.

In Fig. 21 are two side by side   Shaft sinks with 22a and 22b and two side by side Wave crests designated 22c and 22d. If you now the Half honeycomb shaft with part 22a folds about fold line 2, so that the wave runs along a vertical plane, and the striped area with the part 22b around the Fold line 3 folds, so that the half honeycomb wave also runs along a vertical plane, touch the Shaft sinks 22a and 22b each other and it becomes a row 23 formed by hexagonal honeycombs, as in the top row Fig. 22 correspond. This folding will be simultaneous the bridging parts 16 about the fold line 4 in the Bent back horizontally, and the half-honeycomb wave with the Part 22d is folded so that the half honeycomb waves are perpendicular stand, the surfaces 22c and 22d then touching and can be permanently connected. Thereby the second row 24 of cells in FIG. 22 emerges, the is offset from the first row 23, as in Honeycomb structures is the case.

The result is that with bridging parts 22 by folding Wave structures in mutually perpendicular directions emerged, which promises easy manufacture because you can do this by rolling.

23 shows an embodiment of a Cut with U-shaped cuts 9. This will flap formed by the fold line 7 and 5 in two Tab portions 14, 15 and 17, 18 are divided. The other features correspond to the embodiment according to FIG 20. The tab portion 14 is bent down and the Flap section 15 placed horizontally during the Tab portion 17 is bent upwards and the Tab portion 18 is also placed horizontally. After folding in two different directions, like with 21 and 22, the Tab sections 14 and 17 to respective crossbars, which enforce the respective cells 23 and 24, and Tab portions 15 and 18 become pads,   which span the respective cells 23, 24, as shown in Fig. 24 is given. The flap sections 15 and 18 offer additional pads for a possible Sandwich top layer.

Fig. 25 shows another design possibility the folded honeycomb. The starting material again has a U-shape Sections 9, however, the flaps thus formed 14 and 17 are not interrupted by fold lines. Rag 14 and 17 are bent vertically up or down, which creates stiffening webs within the respective cells arise.

Fig. 26 shows another design possibility the folded honeycomb, namely the tabs 14, 17 in their leave the respective level 20 or 21. With appropriate Length of the flaps 14, 17 border them on Bridging sections 13, 16 and can on the edges the cell walls 22 are glued. If the lobes 14, 17 are correspondingly long, it is also possible to end the Tab 14 below the respective adjacent one Bridging sections 13 to hide one to achieve natural cohesion. The same goes for with respect to the ends of the tabs 17 and Bridging sections 16. Finally, it is also possible the tabs 14, 17 on their respective Bridging sections 13, 16 (by gluing or the like) to attach to a continuous top layer to win, which spans the cells and thus the honeycomb solidified.

27 shows a blank for a transition between cells of different heights in the honeycomb a wedge-shaped tapered area, and FIG. 28 outlines such honeycombs. Since the strips 22 the Forming cell walls, strips 22 need to be higher expanding cells. Unless the edges of the Cell walls in the boundary surfaces 70, 71 of the wedge shape the height of the cell wall of each cell must be Side of the chisel tip is lower than the side of the   Wedge extension. Therefore the respective width is the Stripes 22 variable - also locally, within the stripes 22 - as shown in Fig. 27. Rag 14 and 17 are used as additional cover strips, and you front free end 15, 18 is under the respective adjacent bridging part 13 or 16 inserted. Of the The blank of Fig. 27 contains some narrow die cuts 72. It is of course also possible to apply the tabs 14, 17 shorten their respective free ends so that after the Production of the half-honeycomb shafts, the bridging parts 13, 16 just touch. It is understood that the tabs 14, 17th can also be glued to the free edges of the cell walls can, as with the top layers of Sandwich structures is known.

While in the previous embodiments the Areas 20 or areas 21 each have a constant width had, it is also possible to increase the width of these areas 20, 21 to vary, for example the areas 20 opposite to make the areas 21 increasingly wider (FIG. 29). This causes the honeycomb to curve transversely to the direction of the strip generated (FIG. 30), and that with the wave crest surfaces 20 generated area parts span like that of the trough areas created areas like this for example with a wing profile on the wing nose is desirable.

To the manufacture of the folding honeycombs described is still add the following:

The first step is to supply sheet material, where fold lines 1-8 can be embossed, but what is not absolutely necessary.

As a second step, the cuts 9 are made, for example by punching rolls.

The third step is the continuous strip-shaped areas 22 trapezoidal around the lines 5, 6, 7, 8 folded, i.e. the half-honeycomb waves with wave crests and shaft sinks. This shortens the Dimension of the material in the feed direction or in   Cross direction. There are rollers with trapezoidal teeth the top and bottom of the material used that way mesh that the half-honeycomb waves arise. To do that Tool to different width of the continuous strip-shaped areas 22 to adapt, it is possible to Assemble rollers from individual sprockets that be driven from a common spline.

In an intermediate step can be activated Adhesive areas in the strips between the fold lines 6 and 7 and 8 and 5 are attached, which the Identify shaft crests and sinks in Fig. 21.

The next step is to bend the flaps 14 and 15, if there are any and are bent should.

The next step is the folding along the continuous fold lines 1, 2, 3 and 4, where Square waves arise in their wave crests or Wave valleys to lie the pads 13 and 16 respectively come. The material is shortened again.

Within the scope of the invention are also approximate To understand square waves as they are used in the manufacture of Honeycombs with changing honeycomb heights (Fig. 28) or at curved honeycomb (Fig. 30).

As a last step, the wave crests or Wave sinks of the half honeycomb waves connected to each other, if such a connection is provided for the structure is. Adhesion is the most suitable type of connection, however, welding and soldering is also possible.

If the crests or sinks are not to be glued together, it is also possible to Attach tabs 14, 17 to the bridging sections, to ensure a certain cohesion of the honeycomb.

Before attaching the shaft crests or sinks to each other or the flap at the bridging sections the structure can be kept in the form that it should finally accept. The honeycomb then takes off with no inner Tensions, for example, a shell shape that as   Core layer for a sandwich structure diverse Applications.

Since the manufacturing process largely uses rollers works, low manufacturing costs can be expected. That is why the manufacture of packaging material made of cardboard or paper. Opposite the The new packaging material has a conventional corrugated cardboard better compressive strength and does not bend easily Bending loads. In addition, the job starts at Shock loads significantly larger, i.e. the suitability as Damping material when transporting packaged goods improved.

When the folding honeycomb is deformed, there are many webs and Walls affected so that a large deformation energy can be included. The honeycomb is therefore suitable for many crash structures that involve energy consumption.

Fig. 31 shows a blank of material that is can be deep drawn or deformed in a similar way. This happens all light metal into consideration, but can also Fabric and fiber structures from a layer plane permanently deform, possibly also with the participation of Warmth and moisture (paper, cardboard). The intended Deformation is caused by fold lines 1, 2, 3, 4 and 5, 6, 7, 8 indicated. Along fold lines 1, 2, 3, 4 run slit-like cuts 9, between which there are stripe-shaped regions 20, 21, 22 extend. Regarding of the strip-shaped regions 20, the slots 9 face each other opposite, and this also applies to the strip-shaped Areas 21 too, but the slit-like incisions 9 of the area 20 with respect to the slot-like incisions 9 of area 21 offset from one another. Between slot-like incisions 9 are bridging sections 13 and 16 provided so that the web shown one forms a coherent, flat body.

The strip-shaped areas 22 become Half honeycomb waves deformed, as shown in Fig. 32 is. The shaft sinks are 22a and 22b and   Wave crests designated 22c and 22d. The stripe-shaped Areas 20, 21 are aligned to the crests or Shaft sinks. At the bridging sections 13 and 16, respectively the respective half-waves hang together.

To produce the folded honeycomb structure of FIG. 33 32 is around the fold lines 2, 3, 4, 1 folded in the manner described in the description of the Fig. 21 has been described. So it will be Wave sinks 22a and 22b and then the wave crests 22c and 22d are overlapped and optionally bonded to each other so that the hexagonal 22 as the middle layer in FIG. 33 arises. Since nothing in the cutting of Fig. 31 the stripe-shaped remains Areas 20, 21 receive and cover those from the strip-shaped areas 22 obtained hexagonal Folded honeycomb structure. This structure of Fig. 33 shows from home out of a certain stability, but by bonding the Cut edges on the contact surfaces a considerable Increased stability can be achieved, which is why is preferred.

Depending on the material from which the folded honeycomb according to Fig. 33 is made, it is suitable as a lightweight structure, as packaging material or as a crash structure.

Claims (45)

1. Folded honeycomb, in particular as a sandwich core layer, formed from a plurality of similar cells arranged in rows, having the following features:

   the cells have lateral cell walls which adjoin each other in an annular configuration to form cell openings;

   transversely relative to the cell walls the cells are delimited by honeycomb boundary planes in which the openings of the cells lie;

   the folded honeycomb is folded from a continuous flat piece of sheet material cut to size and provided with cuts (9) to form strip-shaped regions (20, 21, 22);
   characterised by the following features:

   the strip-shaped regions are subdivided into a first plurality (22) and into a second plurality (20, 21) which alternate over the flat, cut piece;

   the second strip-shaped regions (20, 21) have bridging portions (13, 16) which connect the respectively adjacent first strip-shaped regions (22) together;

   the first strip-shaped regions (22) are folded through about 90° relative to the second strip-shaped regions (20, 21), wherein the bridging portions (13, 16) come to lie in the planes in which the openings of the cells lie and partially or completely bridge said openings.
2. Folded honeycomb according to claim 1 with the following features:

   the first strip-shaped regions (22) are folded to form half-honeycomb corrugations with corrugation ridges (22c, 22d) and corrugation troughs (22a, 22b) which have flat portions;

   adjacent half-honeycomb corrugations touch each other with said flat portions of their corrugation ridges or corrugations troughs in order to form in each case a row of cells; and

   each bridging portion (13, 16) bridges an associated cell.
3. Folded honeycomb according to claim 2 characterised in that the corrugation ridges (22c, 22d) or the corrugation troughs (22a, 22b) are durably connected together.
4. Folded honeycomb according to claim 2 or 3 characterised in that the fold spaces of the first strip-shaped regions (22) are uniform and four folds (5, 6, 7, 8) form a period.
5. Folded honeycomb according to claim 4 characterised in that the bridging portions (13, 16) are arranged on the second strip-shaped regions (20, 21) in periods corresponding to the folds (5, 6, 7, 8) of the first strip-shaped regions (22).
6. Folded honeycomb according to claim 4 or 5 characterised in that the cuts (9) in the second strip-shaped regions (20, 21) include three quarters of a period.
7. Folded honeycomb according to one of claims 2 to 6 characterised in that the cuts (9) are rectangular.
8. Folded honeycomb according to one of the claims 2 to 6 characterised in that the cuts (9) are U-shaped and form tabs (14, 17).
9. Folded honeycomb according to claim 8 characterised in that the tabs (14, 17) stay in the plane of the crest of the corrugation (20) or the plane of the trough of the corrugation (21) respectively.
10. Folded honeycomb according to claim 8 characterised in that the tabs (14, 17) are folded out of their respective plane of the crest of the corrugation or plane of the trough of the corrugation.
11. Folded honeycomb according to claim 10 characterised in that the free ends (15, 18) of the tabs (14, 17) are folded into the local plane of the trough of the corrugation or plane of the crest of the corrugation.
12. Folded honeycomb according to one of the claims 2 to 6 characterised in that the cuts (9) are slit-shaped so that the second strip-shaped regions (20, 21) are uninterrupted.
13. Folded honeycomb according to claim 12 characterised in that the slit-shaped cuts (9) are disposed in an opposing relationship to each other in pairs on the second strip-shaped regions (20, 21) and pairs of slits of adjacent second strip-shaped regions (20, 21) are displaced relative to each other.
14. Folded honeycomb according to one of claims 2 to 13 characterised in that the strip width of the first strip-shaped regions (22) varies in accordance with the desired local layer thickness of the folded honeycomb.
15. Folded honeycomb according to one of claims 2 to 14 characterised in that differing strip widths of the second strip-shaped regions for the corrugation crests (20) and the corrugation troughs (21) are selected in order to form local curvatures of the folded honeycomb.
16. Folded honeycomb according to claim 1 with the following features:

    the cell walls are formed by two series of linking walls (14, 17, 22, 44, 50, 51, 52);

    the first series of linking walls (22; 44, 52) extends on average in a first direction;

    the second series of linking walls (14, 17; 50, 51) extends in a second direction transversely with respect to the first direction;

    the linking walls (14, 17, 22; 44, 50, 51, 52) are delimited by cut edges (11, 12; 41, 42) and fold edges (5, 6, 7, 8; 35, 36) of the flat, cut piece;

    a first group of connection surfaces (13, 16; 43, 46) is formed by the bridging portions which have stayed in the honeycomb boundary planes and which are delimited by three fold edges (1, 2, 3, 4, 5, 6; 31, 32, 33, 34, 35, 36) and a cut edge (10; 40).
17. Folded honeycomb according to claim 16 characterised in that a second group of connection surfaces (15, 18; 45, 48) is formed by folded portions of the flat, cut piece, which are folded into the honeycomb boundary plane and which are delimited by at least two cut edges (10, 11, 12; 40, 41, 42).
18. Folded honeycomb according to claim 16 or 17 characterised in that a third group of connection surfaces (27) is formed by portions of the flat, cut piece, which are folded from the linking walls into at least one honeycomb boundary plane and which extend transversely to the first or second group of the connection surfaces.
19. Folded honeycomb according to claim 16 to 18 characterised in that cut edges (11, 12; 40) which are in contact with linking walls are connected thereto by glueing, soldering or welding.
20. Folded honeycomb according to one of the claims 16 to 19 characterised in that the flat, cut piece is folded along continuous fold lines (1, 2, 3, 4) into right-angled corrugations which form a plurality of surfaces of the crest of the corrugations and of surfaces of the trough of the corrugations from the second strip-shaped regions (20, 21) as well as the first series of the linking walls from the first strip-shaped regions (22),

    the cuts (9) in the flat, cut piece for forming the second series of the linking walls (14, 17) are U-shaped, wherein the cut edges (11, 12) extend in accordance with the arms of the U-shape at an acute angle or coincidentally with the continuous fold lines (1, 2, 3, 4) and the cut edge (10) extends in accordance with the base of the U-shape transversely with respect to the continuous fold lines (1, 2, 3, 4), the U-shaped cuts (9) are arranged in rows along the surfaces of the crest of the corrugations (20) and/or the surfaces of the trough of the corrugations (21) at such spacings that the first group of the connection surfaces (13, 16) is formed thereby, and

    the linking walls (14, 17) of the second side are folded out of the respective plane of the corrugation crest and/or the corrugation trough along tab fold lines (5, 6) into the honeycomb layer.
21. Folded honeycomb according to claim 20 characterised in that the tabs within the U-shaped cuts (9) are bent over at their free ends to form tongue surfaces which form the second group of connection surfaces (15, 18).
22. Folded honeycomb according to claim 20 or 21 characterised in that the tab fold line (5) of adjacent rows of the U-shaped cuts (9) are flush with each other.
23. Folded honeycomb according to claim 20 or 21 characterised in that the tab fold lines (5, 6) of adjacent rows of the U-shaped cuts (9) are displaced relative to each other.
24. Folded honeycomb according to claim 23 characterised in that the linking walls (22) of the first series are formed transversely to the plane thereof.
25. Folded honeycomb according to claim 24 characterised in that mutually opposing linking walls (22) are deformed away from each other to form hexagonal folded honeycombs (Figure 9).
26. Folded honeycomb according to claim 24 characterised in that mutually opposing linking walls (22) are shaped with respect to each other to form interpenetrating patterns (Figure 10).
27. Folded honeycomb according to claim 24 characterised in that the linking walls (22) of the first series are shaped in a stepped configuration in order to abut against the linking walls (14, 17) of the second series (Figure 11).
28. Folded honeycomb according to one of the claims 16 to 19 characterised in that the strip-shaped regions of the flat, cut piece are subdivided into narrower and wider strips (55, 56, 57, 58) which are separated from each other by fold edges (35, 36) and cut edges (37, 39), wherein the cut edges form interrupted meander portions,

    the narrower strips (55, 57) form right-angled corrugations in planes perpendicularly to the longitudinal extent of the folded honeycomb layer, wherein the surfaces of the crest of the corrugations (43, 48) or the surfaces of the trough of the corrugations (45, 46) of adjacent narrow strips (55, 57) alternately represent the first (43, 46) or the second (45, 48) group of connection surfaces and the flank surfaces (44) from a part of the first series of the linking walls, and

    the wider strips (56, 58) form right-angled corrugations in the plane of the folded honeycomb layer, the surfaces of the crest of the corrugations (50) and the surfaces of the trough of the corrugations (51) representing the second series of the linking walls and the flank surfaces (52) together with the flank surfaces (44) of the narrower strips (55, 57) forming the first series of the linking walls.
29. Folded honeycomb according to claim 28 characterised in that the surfaces of the crest of the corrugations (43, 48) or surfaces of the trough of the corrugations (45, 46) of the narrower strips (55, 57) are half as wide as the flank surfaces (44).
30. Process for the production of the folded honeycomb according to one of the claims 2 to 15, having the following steps:

    a) a sheet material of metal, plastic material, cloth, fiber composite material, fiber reinforced paper or conventional paper or cardboard is provided;

    b) the sheet material is cut to size and in that operation provided in the second strip-shaped regions (20, 21) with the cuts (9), between which the bridging portions (13, 16) remain, forming a flat, cut piece in which the first strip-shaped regions (22) and second strip-shaped regions (20, 21) alternate with each other and the bridging portions (13, 16) connect together the first strip-shaped regions (22);

    c) the first strip-shaped regions (22) are formed transversely with respect to the strip direction in order to produce half-honeycomb corrugations with corrugation ridges (22c, 22d) and corrugation troughs (22a, 22b) on which the flat portions are formed;

    d) the flat, cut piece, which is formed in the first strip-shaped regions (22), is folded into right-angled corrugations along fold lines (1, 2, 3, 4) which separate the first and second strip-shaped regions (20, 21, 22) from each other, wherein the bridging portions (13, 16) come to lie in the corrugation crests or corrugation troughs; and

    e) planar portions of the corrugation ridges (22c, 22d) or corrugation troughs (22a, 22b) are laid on the opposing planar portions of the corrugation troughs (22a, 22b) or corrugation ridges (22c, 22d).
31. A process according to claim 30 characterised in that the flat portions which have been laid onto each other are the corrugation ridges (22c, 22d) and the corrugation troughs (22a, 22b) of the half-honeycomb corrugations, which are fixedly connected to each other.
32. A process according to claim 30 or 31 characterised in that deformation of the first strip-shaped regions (22) is effected by bending or folding.
33. A process according to claim 30 or 31 characterised in that deformation of the first strip-shaped regions (22) is effected by deep-drawing.
34. A process for the production of a folded honeycomb according to one of the claims 20 to 27, with the following steps:

    a) a sheet material of metal, plastic material, cloth, fiber composite material or fiber reinforced paper, optionally with prepared glued, soldered or welded connection locations (19), which are to be arranged in line with tab fold lines (5, 6), is provided;

    b) U-shaped cuts (9) are produced in rows in the second strip-shaped regions (20, 21) of the sheet in order to prepare flat, cut pieces with linking walls (14, 17) of a second series which are separated from each other by bridging portions (13, 16) which form connection surfaces of a first group, wherein the cut edges (11, 12) extend in accordance with the arms of the U-shape at an acute angle or coincidentally with the continuous fold lines (1, 2, 3, 4) to separate first strip-shaped regions (22) from the second strip-shaped regions (20, 21) and the cut edge (10) extends in accordance with the base of the U-shape transversely with respect to the continuous fold lines (1, 2, 3, 4);

    c) the linking walls formed from the first strip-shaped regions (22) are optionally deformed, after steps d) and e), transversely relative to the strip direction (Figures 9, 10 and 11);

    d) the flat, cut piece is folded into right-angled corrugations along the continuous fold lines (1, 2, 3, 4) in order to form surfaces of the crest of the corrugations and surfaces of the trough of the corrugations with the second strip-shaped regions (20, 21) and linking walls of a first series with the first strip-shaped regions (22);

    e) the linking walls (14, 17) of the second series are folded out of the respective plane of the corrugation crest or the corrugation trough respectively into the layer formed by the folded honeycomb along the tab fold lines (5, 6) wherein the bridging portions (13, 16) are maintained in the said plane of the crest of the corrugation or the said plane of the trough of the corrugation, respectively.
35. Process according to claim 34 characterised in that the ends of the linking walls (14, 17) are bent over to form tongue surfaces (15, 18) which form a second group of connection surfaces.
36. Process according to claim 34 or 35 characterised in that the U-shaped cuts (9) in the rows are so arranged that the tab fold lines (5, 6) of the linking walls (14, 17) of adjacent rows are flush with each other.
37. Process according to claim 34 or 35 characterised in that the U-shaped cuts (9) in the rows are so disposed that the tab fold lines (5, 6) of the linking walls (14, 17) of adjacent rows are displaced relative to each other.
38. Process according to one of the claims 34 to 37 characterised in that the cut edges (11, 12) of the arms of the U-shape are fixedly connected to the linking walls formed from the first strip-shaped regions (22) along prepared connect on locations (19).
39. Process according to claim 38 characterised in that the linking walls of the first series formed form the first strip-shaped regions (22) are formed transversely to the plane thereof to form hexagonal folded honeycombs.
40. Process according to claim 38 characterised in that the linking walls of the first series formed from the first strip-shaped regions (22) are formed transversely with respect to the plane thereof to form interpenetrating patterns.
41. Process according to claim 38 characterised in that the linking walls of the first series formed from the first strip-shaped regions (22) are formed transversely with respect to the plane thereof to form stepped edges which partially abut against the linking walls (14, 17) of the second series.
42. Process for the production of the folded honeycomb according to claim 28 or 29, with the following steps:

    a) sheet material of metal, plastic material, cloth, fiber composite material or paper is provided;

    b) the sheet material is provided with meander cuts (37, 39) to form flat, cut pieces, wherein the meander cuts (37, 39) are displaced relative to each other and the flat, cut pieces are subdivided along first fold lines (35, 36) into narrower and wider strips (55, 56, 57, 58);

    c) the flat cut piece is folded in mutually overlapping relationship along the first fold lines (35, 36) to form an overlapping structure;

    d) the overlapping structure is deformed along second fold lines (31, 32, 33, 34) which extend perpendicularly to the first fold lines (35, 36) into right-angled corrugations so that the narrower and wider strips (55, 56, 57, 58) form individual right-angled corrugations which are inserted one into the other; and

    e) the right-angled corrugations which are inserted one into the other and pulled apart, in which case the narrower strips (55, 57) are arranged with their right-angled corrugations in planes perpendicularly to the plane of the folded honeycomb and the wider strips (56, 58) are arranged with their right-angled corrugations in the plane of the folded honeycomb.
43. Process according to claim 42 characterised in that the flank: surfaces (44) of the right-angled corrugations of the narrower strips (55, 57) are made flush with or slightly overlap the flank surfaces (52) of the wider strips (56, 58) and are fixedly connected thereto to form the first series of the linking walls (44, 52).
44. Use of the folded honeycomb according to one of the claims 1 to 29 as packaging material.
45. Use of the folded honeycomb according to one of the claims 1 to 29 as a crash structure.