JPH0446221B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Field of Application The present invention is utilized for core materials used in flash panels and the like, and for the production of this core material.

(b) Prior art and its problems Plywood with a so-called sandwich structure such as a flat panel has a core made of a lightweight material such as paper or synthetic resin, and wood or other rigid plate-like members on both sides. It is formed by combining.

As the core material, a honeycomb-shaped core material having a large number of tortoiseshell-shaped cells, generally called a honeycomb core, is used.

As shown in FIG. 9 (showing a contracted state) and FIG. 10 (showing an expanded state), such a honeycomb core has a plurality of core rows 51, 52, 5.
3 are stacked in layers and connected to each other.

As shown in FIG. 11, the core rows 51 and 52, for example, are a pair of core webs that have a plurality of bent portions 54 and are connected facing each other so as to define cells 55 between the bent portions. 56,57 or 58,5
It is formed from 9.

When the honeycomb core formed in this way is pulled in the direction of arrow D-D shown in FIG.
5 and cells 60 defined between adjacent core columns.
is deformed into an expanded state as shown in FIG. 10 while increasing its area.

However, as is clear from comparing FIG. 9 and FIG. 10, the increase in the area of the cell due to the elongation of the core in the D-D direction is necessarily perpendicular to the D-D direction of each cell. ie, the longitudinal direction of the core row, thereby reducing the overall width of the core.

Thus, as the core stretches or expands,
The inevitable reduction in the width of the core means that when inserting the core between plywood boards, the dimensions of the core in the contracted state must be determined in advance according to the degree of elongation of the core, and such a determination This is a major drawback since it is very difficult to process when dimensional accuracy is considered, and improvement in this point has been desired.

Furthermore, when the core is filled between the edge frame materials, it is desirable that the core expands or contracts simultaneously in both the stretching direction and the width direction perpendicular to this. As a result, the core and widthwise extensions could not be performed at the same time.

(c) Object of the Invention An object of the present invention is to overcome the problems of the prior art as described above, and to provide a core whose width does not decrease even when the core is elongated, and a method for manufacturing such a core. It is.

(d) Structure of the Invention The core material of the present invention includes a plurality of core rows each consisting of a pair of belt-shaped core webs that are connected face-to-face to define cells between them. The core rows are stacked in layers and connected to each other, thereby defining cells surrounded by core webs between adjacent core rows. Each of the cells defined between each pair of core webs and the cells defined between the adjacent core rows is arranged so that when the core material contracts, the inside of the cell is formed on each side in the longitudinal direction of the core rows. The cell is configured to have at least two pairs of sides extending toward each other and connected inwardly of the cell. Therefore, the core can expand and contract in both the longitudinal direction of the core row and the direction orthogonal to this longitudinal direction.

Further, according to the present invention, there are provided a plurality of core rows each consisting of a pair of belt-shaped core webs that are connected face-to-face to define a cell between them, and these plurality of core rows are stacked in a layered manner. In this way, adjacent core rows are also connected to each other so that cells surrounded by the core web are defined, and furthermore, the upper and outermost core rows of the core rows connected in a layered manner are A core material is provided, which is formed by connecting a plate-shaped side plate member to a lower core row, and expands and contracts in a direction perpendicular to the longitudinal direction of the core row. Each of the cells defined between each pair of core webs and the cells defined between the adjacent core rows is such that when the cores contract on at least one side in the longitudinal direction of the core rows, The cell has at least two pairs of sides that move inwardly and are connected inside the cell.

Further, the method for producing a core material of the present invention includes the steps of: forming a sawtooth-like stacked body having a large number of pleats by alternately folding a belt-shaped core web at approximately equal intervals along the longitudinal direction of the core web; On both sides of the pleats, excluding the adjacent folds that appear at predetermined intervals, temporarily fixing the adjacent folds to form a press-welded stacked body; forming a core web precursor by expanding adjacent pleats so as to alternately form an upper surface and a lower surface, and reversing every other core web precursor and stacking and joining them;
slicing the joined core web precursor into predetermined widths.

(e) Embodiment FIG. 1 is a plan view showing one embodiment of the core material of the present invention, and in this figure, the core material 1 is stretched in the direction of elongation (direction indicated by arrow A-A in FIG. 1). in approx.
Shown at 75% elongation. FIG. 2 shows the core material in a state of contraction and elongation of approximately 25% in the direction of arrow C--C.

This core material 1 has core rows 2, 3, and 4 that extend in a direction substantially perpendicular to the elongation direction, that is, the width direction (direction indicated by arrow B-B in FIG. 1), and It is comprised of side plate members 7 and 8 connected to both sides in the direction. In this example, the number of core rows is 3, but
The number of core rows can be arbitrarily selected depending on the purpose and use.

Each core row has a bent portion 9 as shown in FIG.
It is formed by connecting a pair of core webs 11 and 12, in which connecting portions 10 are alternately formed, to each other in a symmetrical facing relationship. The core rows thus formed are overlapped and connected with the outer surfaces of each bent portion 9 aligned, and side plate members 7 and 8 are further connected to the outside of the core rows 2 and 4 on both sides. As a result, the core 1 shown in FIG. 1 is formed.

As the material of the core web, single-sided corrugated cardboard, double-sided corrugated cardboard, metal foil or plastic sheet can be used.

The core 1 formed as described above is formed between the opposing bent portions 9, 9 of the pair of core webs 11, 12 forming each core row, and between the connecting portions 10, 10 of the core webs of adjacent core rows. Cell 1 defined by
3, 14, and both sides of the cell in the width direction are defined by a plurality of V-shaped sides 15, 16, 17, 18 extending inwardly of the cell. ing.

As is clear from FIG. 1, such a plurality of V-shaped sides can be efficiently joined by partially joining the outer surfaces of the bent portions 9 instead of over the entire surface. can be done, but of course V
This is also possible by forming a predetermined number of sides of the letter shape. It is desirable that the length of the joint (the length along the longitudinal direction of the core row) be approximately 1/5 of the total length of the bent portion 9.

Each cell has V-shaped sides 15, 16,
17 and 18, it becomes possible for the core to expand significantly in the stretching direction A-A shown in FIG.

When the side plate members 7 and 8 of the core 1 in the 25% stretched state shown in FIG. , which causes each cell to elongate in the elongation direction. Therefore, each core row can expand in the elongation direction. During this expansion, since the core rows 2 and 4 on both sides are fixedly connected to the side plate members 7 and 8, respectively, the width direction B of each core row that occurs when the core rows are not fixed is -B is restricted from elongating, so that the upper and lower sides of each cell are alternately inclined in the width direction as shown in FIG. As is clear from FIG. 1, the width of the core does not decrease due to the elongation of the core.

Core 1 with side plate members 7 and 8 removed,
When it is stretched in the stretching direction, it also stretches in the width direction. In other words, if the side plate members are removed and the core is formed using only the core rows, elongation in two axial directions will occur simultaneously, and depending on the purpose of use, the core may be formed in this way. be. For example, it can be applied to sanderch panels made of spherical art materials.

Next, the method for manufacturing the core material of the present invention will be explained with reference to FIG. 4 and subsequent figures.

A sawtooth-like stacked body 2 consisting of a large number of pleats P ₁ to P ₁₆ is obtained by alternately bending the sheet-like core web 20 shown in FIG. 4 at approximately equal intervals along the longitudinal direction.
form 1.

Next, adhesive S is applied to the vicinity of both sides of each pleat, and then the stacked bodies are brought into pressure contact with each other as shown in FIG. 5, so that the adjacent pleats are temporarily fixed by adhesive.

What is important in applying this adhesive is not to make sure that all adjacent folds are joined, but to make sure that unjoined folds appear in a controlled manner at a predetermined interval. It is.

That is, in the embodiments shown in FIGS. 4 to 7, the pleats P ₃ , P ₄ ; P ₆ , P ₇ ; P ₉ , P ₁₀ ; P ₁₂ ,
It should be noted that no adhesive was applied to the adjacent surfaces of P ₁₃ and P ₁₅ to _{P 16} .

The width and length of the adhesive are economical if they are relatively thin and short as shown, but they can be appropriately selected depending on the rigidity, thickness, etc. of the material of the core web.

Furthermore, this temporary fixing is not limited to using adhesive, but can also be done by welding means such as hot melt.

The superimposed body 22 whose both sides are temporarily fixed as described above
is expanded so that the unjoined adjacent pleats alternately form upper and lower surfaces, a preformed core web precursor 23 is formed by temporary fixing as shown in FIG. The core web 11 or 12 shown in FIG. 3 is obtained by cutting off the stopped both sides and slicing the precursor at a predetermined width.

The steps described above are repeated to form a large number of core webs, and these core webs are joined facing each other so that the folded portions 9 and connecting portions 10 are substantially aligned, thereby forming the core array shown in FIG. 2 is formed.

In forming this core row, as shown in FIG. 7, adhesive is applied on the connecting portion 10 of one of the core webs 12 in the width direction of this core web, and these core webs 11 and 12 are pressed against each other. It is carried out by.

What is important in this regard is the width of the adhesive d
does not extend over the entire length l of the connecting portion 10 in the longitudinal direction.

In this way, by partially adhering the opposing connecting portions, rather than over the entire length of each, it is possible to increase the sides of the V-shape that extend inwardly of each cell. This makes it possible to economically increase the expansion rate of the core material.

Furthermore, as shown in FIG. 8, the number of sides of the V-shape can be further increased, but in this case, the distance between the unjoined adjacent folds is increased (for example, as shown in FIGS. 4 to 6). In the figure, P ₃ and P ₄ are replaced by P ₅ ,
It is clear that this can be easily done by doing the following: P ₆ ).

Further, in the above method, the temporarily fixed portion of the temporarily fixed core web is cut and the core web is sliced to form a core web of a predetermined width,
Next, a pair of core webs are joined to form a core row, and then these core rows are overlapped and joined to obtain a core material, but the effect of temporary fixing to maintain a predetermined shape is maximized. For this purpose, the core material can also be manufactured by stacking and joining every other core web precursor in an inverted state, and finally cutting the temporary joint and slicing the core web precursor to a predetermined width. can.

[Brief explanation of drawings]

Figure 1 is a plan view showing the core material of the present invention in a state of approximately 75% expansion, Figure 2 is a plan view of the core material of the present invention in a state of approximately 25% expansion, and Figure 3 shows the structure of the core material. 4 is a perspective view showing the stage of forming the weight body, FIG. 5 is a perspective view showing the state in which the stacked bodies are pressed together, FIG. 6 is a perspective view showing the precursor of the core web, FIG. 7 is a side view showing the step of forming core rows, FIG. 8 is a side view showing the step of forming core rows in another embodiment, and FIG. 9 is a plan view showing the conventional honeycomb core in a contracted state. , FIG. 10 is a plan view showing the expanded state of the honeycomb core shown in FIG. 9, and FIG. 11 is a plan view showing the structure of the core array of the honeycomb core shown in FIG. 9. 1: Core material, 2, 3, 4: Core row, 7, 8: Side plate member, 9: Bent part, 10: Connecting part, 11, 12:
Core web, 11, 12': Core web, 13,
14: Cell, 15, 16, 17, 18: Side, 2
0: Sheet-like core web, 21: Superimposed body, 2
2: Pressed superimposed body, 23: Core web precursor,
P ₁ ...P ₁₆ : Fold section.

Claims (1)

[Scope of Claims] 1. A plurality of core rows each consisting of a pair of belt-shaped core webs connected face-to-face to define a cell between them are provided, and these plurality of core rows are stacked in a layered manner. The core webs are connected to each other in a state in which the core webs are connected to each other so as to define cells surrounded by core webs between adjacent core rows, and the core webs are arranged in the longitudinal direction of the core rows and orthogonal to the longitudinal direction. Each core web is made up of a connecting part and a bent part, and among the pair of core webs constituting each core row,
The connecting portion of one core web is bonded to the connecting portion of the other core web, and each bent portion of the pair of core webs is bonded to each bent portion of the core webs constituting an adjacent core row, and only a portion thereof is bonded to each of the bent portions of the core webs. Each of the cells defined between the pair of core webs and the cells defined between the adjacent core rows moves inward when the core material contracts on each side in the longitudinal direction of the core rows. A core material characterized in that it has at least two pairs of side edges connected inside the cell. 2. A plurality of core rows each consisting of a pair of belt-shaped core webs that are connected face-to-face and formed to define a cell between them are provided, and these multiple core rows are stacked in layers and connected to each other. As a result, cells surrounded by the core web are defined between adjacent core rows, and the upper and lower core rows located at the outermost side of the layered core rows are further defined. The core material is formed by connecting plate-shaped side plate members to each other, and expands and contracts in a direction perpendicular to the longitudinal direction of the core row, and each core web has a connecting part and a bent part. Of the pair of core webs constituting each core row, the connecting portion of one core web is connected to the connecting portion of the other core web, and each bent portion of the pair of core webs is connected to each of the core webs constituting the adjacent core row. Only a portion of each of the bent portions is bonded, and each of the cells defined between each pair of core webs and the cells defined between the adjacent core rows are connected to each other in the longitudinal direction of the core rows. A core material characterized in that it has at least two pairs of side edges that move inward of the cells when the core material contracts and are connected inside the cells. 3. A step of folding a belt-shaped core web alternately at approximately equal intervals along its longitudinal direction to form a sawtooth-shaped heavy body having a large number of folds, and forming phases appearing at predetermined intervals on both sides of each fold. excluding the adjacent pleats, temporarily fixing only a part of the adjacent pleats to form a press-welded superimposed body; and a step of forming a core web precursor by spreading it out to form a lower surface, and a step of inverting every other core web precursor and stacking them to join only a part of each of the overlapped parts, A method for manufacturing a core material comprising the step of slicing the joined core web precursor into predetermined widths.