JP3426089B2 - Honeycomb core made of fiber reinforced plastic - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a honeycomb core made of fiber reinforced plastic. That is, a fiber-reinforced plastic (FR
The present invention relates to a honeycomb core manufactured by P). 2. Description of the Related Art FIG. 2 is a perspective view of a main part of a honeycomb core made of fiber reinforced plastic according to a conventional example of this kind.
FIG. 1A shows a fiber-reinforced plastic sheet as a base material, FIG. 2B shows a corrugated sheet, and FIG. A honeycomb core 1 made of a fiber-reinforced plastic of this type is made of a cell made of a fiber-reinforced plastic sheet 4 as a base material, in which a resin is attached to a plain woven fiber in which a warp 2 and a weft 3 intersect by adhering, impregnating, mixing, or the like. A wall 5 is formed, and is formed of a planar aggregate of a large number of hollow column-shaped cells 6 defined by the cell walls 5. In this type of conventional honeycomb core 1 made of fiber reinforced plastic, the fiber direction of the warp 2 of the fiber reinforced plastic sheet 4 as a base material constituting the cell wall 5 is parallel to the cell end face A. At the same time, the fiber direction of the weft yarn 3 was parallel to the cell axis B. The corrugated sheet 7 shown in FIG. 2 (2) is formed in the course of manufacturing the fiber reinforced plastic honeycomb core 1 using the fiber reinforced plastic sheet 4 as a base material. [0003] The following problems have been pointed out in such a conventional example. That is, this kind of honeycomb core 1 made of fiber reinforced plastic
After the fact, the cell end surface A is often formed into a curved surface as a whole so as to have a predetermined curvature. At this time, the cell wall 5 made of the fiber reinforced plastic sheet 4 as a base material is damaged by cracks, cracks and the like. It was pointed out that the problem was likely to occur. That is, when the honeycomb core 1 made of fiber reinforced plastic is formed into a curved surface from a flat plate or block, the inside of the curve is contracted and deformed, and the outside of the curve is expanded and deformed. In order to perform such a curved surface forming, when a pressing force and a pressing force are applied to both end portions of the honeycomb core 1 in the bending direction C along the cell axis B, fiber reinforcement as a base material of the cell wall 5 is performed. Since the fiber direction of the warp 2 of the plastic sheet 4 is parallel to the cell end surface A, the bending direction C along the cell axis B and the fiber direction of the warp 2 have a positional relationship orthogonal to each other. The pressing force / pressing force of C is hindered by such warp yarns 2 and receives resistance. While the presence of the warp yarns 2 as a main cause and the presence of the weft yarns 3 holding the warp yarns 2 are also combined, the honeycomb core 1 made of fiber-reinforced plastic is generally difficult to form a curved surface.
If a curved surface is forcibly formed, the cell wall 5 is liable to be damaged such as a crack or a crack, which causes a quality problem.
That is, it has been pointed out that the conventional honeycomb core 1 made of fiber reinforced plastic has difficulty in flexibility, flexibility, and high shaping property. The present invention has been made in view of the above circumstances and has been made to solve the above-mentioned problems of the prior art. In the fiber reinforced plastic sheet as a base material of the cell wall, the fiber direction of the warp and the weft is determined. First, by being inclined at a predetermined angle, not parallel to the cell end face or cell axis, first,
At the time of forming a curved surface, damage such as cracks and cracks is prevented, and it is excellent in flexibility, flexibility and high shaping properties.
Moreover, an object of the present invention is to propose a honeycomb core made of fiber-reinforced plastic, which can realize this easily and easily. [0006] The technical means of the present invention for solving such a problem is as follows. In other words, in this honeycomb core made of fiber reinforced plastic, a cell wall is formed by using a fiber reinforced plastic sheet as a base material, which is obtained by combining resin by attaching, impregnating, mixing, etc., a plain woven fiber in which warp and weft intersect, It consists of a planar assembly of a large number of hollow columnar cells defined by the cell walls. In the fiber-reinforced plastic sheet as a base material of the cell wall, the fiber direction of the warp and the weft is inclined at a predetermined angle, not parallel to the cell end face or the cell axis.
Further, the honeycomb core made of the fiber reinforced plastic is entirely formed into a curved surface so that the cell end surface has a predetermined curvature. As described above, the honeycomb core made of the fiber-reinforced plastic is such that the fiber directions of the warp and the weft of the fiber-reinforced plastic sheet, which is the base material of the cell wall, are not parallel to the cell end face and the cell axis but at a predetermined angle. And tilt it. Therefore, when the cell end surface is formed into a curved surface as a whole so as to have a predetermined curvature, the inside of the curved portion is contracted and deformed, and the outside of the curved portion is expanded and deformed. The pressing force and pressing force in the applied bending direction are not hindered by the fiber and do not receive resistance. Thus, the honeycomb core made of fiber reinforced plastic is smoothly formed into a curved surface. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on embodiments of the invention shown in the drawings. FIG. 1 is a perspective view of a main part used for describing an embodiment of the present invention,
FIG. 1A shows a fiber-reinforced plastic sheet as a base material, FIG. 2B shows a corrugated sheet, and FIG. 3C shows a curved surface forming state. FIG. 3 is an explanatory front view of one example of a method for manufacturing a honeycomb core made of fiber reinforced plastic. (1) FIG. 3 shows a prepared fiber reinforced plastic sheet, (2) FIG. FIG. 3 (3) shows a formed corrugated sheet, and FIG. 4 (4) shows a step of stacking and joining corrugated sheets. FIG. 4 is a perspective view of the honeycomb core. FIG. 5 is provided for explaining the curved surface forming of the honeycomb core, (1) FIG. 5 is a schematic perspective view of the whole before the curved surface forming, (2) FIG.
(3) is a plan view of a main part after the curved surface is formed, and (4) is a bottom plan view of the main part after the curved surface is formed. First, referring to FIGS. 1 and 3, a description will be given of a corrugation method as an example of a method of manufacturing the honeycomb core 8 made of fiber-reinforced plastic. In this manufacturing method, first, as shown in FIG. 1 (1) and FIG. 3 (1), a fiber-reinforced plastic sheet 9 as a base material is prepared. This fiber reinforced plastic (FRP)
The sheet 9 is made of a plain woven glass fiber, a Kevlar fiber, a carbon fiber, a ceramic fiber, a metal fiber, a resin fiber, other plain woven fibers, that is, a fiber woven so that the warp yarn 10 and the weft yarn 11 cross sequentially, and an epoxy-based fiber. Resin, polyimide resin, other thermosetting resin or thermoplastic resin,
It consists of a combination of any of adhesion, impregnation, mixing, etc. or a combination thereof. The fiber-reinforced plastic sheet 9 is in a semi-cured state in which it is not yet completely cured, that is, in the form of a prepreg having flexibility and viscosity, and in the form of an extremely thin flat sheet. In the fiber reinforced plastic sheet 9 of the illustrated example, about 125 g / m ² of carbon fiber is used, and the warp yarn 10 and the weft yarn 11 are
About 1,000 fine carbon fibers are collected from each other to make a single carbon fiber. Epoxy resin is attached, impregnated, mixed, and the like at a weight ratio of about 40%. Then, as shown in FIG. 3 (2),
The prepreg-shaped fiber-reinforced plastic sheet 9 serving as a base material is supplied to a corrugating apparatus 13 such as a gear or a rack 12. The prepreg-shaped fiber-reinforced plastic sheet 9 is inserted between the gears and racks 12 of such a corrugating apparatus 13, sandwiched from both front and back sides, and heated and pressurized, whereby (2) in FIG. As shown in FIG. 3 and FIG. 3 (3), the corrugated plate 14 is formed into a corrugated plate 14 made of fiber reinforced plastic in which corrugations are continuously bent. The corrugated plate 14 has a trapezoidal shape, a substantially triangular shape, a substantially square shape, and other various shapes of corrugations, which are linear and parallel in the short direction and continuous in the long direction, and have a predetermined pitch and height. It is formed by bending. Thereafter, the corrugated sheet 14 made of fiber-reinforced plastic molded in this way is dried, for example, by applying a node bond, that is, an adhesive agent 15 to the lower surface of the wave valley or the upper surface of the top of the corrugation. Cut by length. Then, as shown in FIG.
Are vertically shifted by a half pitch of the wave, and are stacked in a laminated block shape having a space as a whole under the positional relationship of matching the valley and the top between the upper and lower parts. A flat plate made of the same fiber-reinforced plastic as the above-mentioned fiber-reinforced plastic sheet 9 may be further interposed between the corrugated plates 14. Thereafter, the corrugated sheets 14 stacked in this manner are heated and pressurized, whereby the resin is cured and the applied adhesive 15 is cured, and the corrugated sheets 14 are bonded to each other (as described above, further). When a flat plate is interposed, each corrugated plate 14 and the flat plate are also bonded.) In the illustrated example, the joining method using the adhesive 15 is adopted, but the joining method using a brazing material or the melt hardening by heating the resin itself constituting the corrugated plate 14 is used instead. A joining method and the like can be considered. By following these steps, FIG.
(3) The honeycomb core 8 made of fiber reinforced plastic shown in FIG. 4 and FIG. 4 is manufactured. And this honeycomb core 8 is formed into a plain weave fiber in which the warp yarn 10 and the weft yarn 11 intersect,
A cell wall 16 is formed by using a fiber-reinforced plastic sheet 9 as a base material, which is obtained by combining, impregnating, mixing, and the like resin, and is a planar assembly of a large number of hollow columnar cells 17 defined by the cell wall 16. Consisting of That is, the honeycomb core 8 made of fiber reinforced plastic is divided into independent spaces by using the corrugated plate 14 (and the above-mentioned flat plate) made of fiber reinforced plastic stacked and joined as described above as a cell wall 16. It consists of a planar assembly of a large number of hollow columnar cells 17 formed. The cross-sectional shape of the cell wall 16 and the cell 17 is typically a regular hexagonal shape as shown in the drawing, but is not limited thereto, and may be trapezoidal, substantially triangular, substantially square, or various other shapes. . This honeycomb core 8 made of fiber reinforced plastic is
Similar to general ones, it has excellent weight ratio strength, is lightweight and has high rigidity and strength.
It has excellent heat insulation and sound insulation properties, has a large surface area per unit volume, and so on, and is widely used as various structural materials. Incidentally, in the honeycomb core 8 made of fiber reinforced plastic, as shown in FIG. 1, the fiber reinforced plastic sheet 9 serving as a base material of the cell wall 16 is used.
Is that the fiber direction of the warp yarn 10 or the weft yarn 11 is the cell end face A
And is not parallel to the cell axis B but inclined at a predetermined angle. These will be described in more detail. In the honeycomb core 8, a cell axis B which is a center line of each cell 17;
The cell 17 has an orthogonal relationship with the cell end surface A, which is the opening end surface of each cell 17 (see FIG. 1C and FIG. 4). Further, in the fiber reinforced plastic sheet 9 which is the base material of the cell wall 16 which defines each cell 17, the warp 10
And the weft yarn 11 are in a mutually orthogonal relationship. At the same time, the warp yarn 10 and the weft yarn 11 of such a fiber reinforced plastic sheet 9 are inclined with respect to the cell end surface A and the cell axis B. That is, first, when preparing the fiber-reinforced plastic sheet 9 at the time of manufacturing, as shown in FIG.
Are prepared in such a manner that they are inclined in the forward or reverse direction between about 15 degrees and about 75 degrees without being parallel (refer to the conventional example in FIG. 2 (1)). This inclination angle is set to 45 degrees in the illustrated example, but is preferably set between about 30 degrees and 60 degrees. Then, using such a fiber-reinforced plastic sheet 9 as a base material, the corrugated sheet 14 shown in FIG.
After that, the honeycomb core 8 made of fiber reinforced plastic shown in FIG. 1 (3) and FIG. 4 is manufactured. Therefore, in the honeycomb core 8, the fiber direction of the warp 10 of the base material does not become parallel to the cell end face A (refer to the conventional example in FIG. 2 (3)). Further, the fiber direction of the weft yarn 11 orthogonal to the warp yarn 10 is not parallel to the cell axis B (see the conventional example in FIG. 2 (3)). That is, the warp 10
The weft yarn 11 and the weft yarn 11 have a fiber orientation that is not parallel to the cell end surface A and the cell axis B, but inclined. When the warp 10 is considered as a reference, the inclination angle is set at about 15 to 75 degrees, preferably about 30 to 60 degrees, for example, 45 degrees with respect to the cell end face A as described above. The honeycomb core 8 made of fiber reinforced plastic is formed into a curved surface as a whole so that the cell end surface A has a predetermined curvature. That is, as shown in FIG. 5A, the honeycomb core 8 having a flat plate shape or a block shape before the curved surface forming is formed as shown in FIG.
As shown in the drawing, both the cell end surfaces A are bent and formed into a curved surface so that each has a predetermined curvature. Then, the regular hexagonal cell 17 on the cell end face A side inside the curve (upper side in the drawing) is formed into a vertically long hexagonal shape (as shown in FIG. ) Shrinking deformation. On the other hand, the cell 17 on the cell end face A side outside the curve (the lower side in the drawing) is (4) in FIG.
As shown in the figure, it is elongated and deformed (to be over-extended) into a horizontally long hexagonal shape. Then, in order to realize such a curved surface forming, as shown in FIG. 1C, a pressing force and a pressing force are applied in the bending direction C at normal temperature or while heating. The present invention is configured as described above. Then, it becomes as follows. In the honeycomb core 8 made of fiber reinforced plastic, the fiber direction of the warp yarn 10 and the weft yarn 11 of the fiber reinforced plastic sheet 9 which is the base material of the cell wall 16 is not parallel to the cell end face A or the cell axis B, but is predetermined. It is inclined at an angle. When the cell end face A is subsequently formed into a curved surface so as to have a predetermined curvature, the honeycomb core 8 made of such a fiber-reinforced plastic is shrunk and deformed at the inside of the curvature, and is formed at the outside of the curvature. Is stretched and deformed. At this time, in order to realize such a curved surface forming, the honeycomb core 8 is formed.
Are applied along the cell axis B in the bending direction C. Now, the honeycomb core 8 made of fiber reinforced plastic is as follows. First, the pressing force and the pressing force in the bending direction C applied during the formation of the curved surface are controlled by the fiber reinforced plastic sheet 9 as the base material of the cell wall 16, that is, the warp yarn 10 and the weft yarn 11. There is no hindrance or resistance. That is, the cell end face A is perpendicular to the cell axis B, and the pressing force and the pressing force are applied in the bending direction C along the cell axis B.
0 and the weft yarn 11 are in a positional relationship in which the fiber direction is not parallel to them and is inclined at a predetermined angle. Therefore, unlike the case where the positions are orthogonal to each other, the warp 10 and the weft 1
1 does not hinder the above-described pressing force / pressing force and does not cause resistance. Thus, the honeycomb core 8 made of fiber reinforced plastic is excellent in flexibility, flexibility, and high shaping properties, and is smoothly formed into a curved surface. Second, such a honeycomb core 8 made of fiber reinforced plastic has a simple structure in which the fiber direction of the warp yarn 10 and the weft yarn 11 of the fiber reinforced plastic sheet 9 which is the base material of the cell wall 16 is inclined. Configuration. That is, when preparing the fiber-reinforced plastic sheet 9 serving as a base material at the time of manufacturing, the warp yarn 10 and the weft yarn 11 are merely cut and arranged so as to be inclined, not parallel, with respect to the long side / longitudinal direction D. According to a conventional manufacturing method, the honeycomb core 8 made of fiber-reinforced plastic is
Easily manufactured. As described above, in the honeycomb core made of fiber reinforced plastic according to the present invention, the fiber direction of the warp or weft of the fiber reinforced plastic sheet as the base material of the cell wall is changed to the cell end face. The following effects are exhibited by tilting at a predetermined angle instead of being parallel to the cell axis. First, damages such as cracks and cracks are prevented during the formation of the curved surface. That is, since the fiber direction of this honeycomb core made of fiber-reinforced plastic is inclined as described above, when the curved surface is formed from a flat plate or block shape, the pressing force and the pressing force in the bending direction are reduced. The surface is smoothly formed without being hindered by the presence of the fiber and receiving resistance. In other words, unlike the honeycomb core made of fiber-reinforced plastic of the above-described conventional example, there is no possibility of forcibly forming a curved surface to cause damage such as cracks or cracks on the cell wall. Become excellent. As described above, the honeycomb core made of the fiber-reinforced plastic is excellent in flexibility, flexibility, and high shaping property. Second, and this is easily and easily realized. That is, the honeycomb core made of fiber-reinforced plastic has a simple configuration in which the fiber direction is simply inclined, and can be manufactured while being excellent in cost. Thus, the first point described above is easily realized. As described above, the effects exhibited by the present invention are remarkable and large, for example, the problems existing in this type of conventional example are surely solved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a main part of a honeycomb core made of fiber-reinforced plastic according to the present invention, which is used for describing an embodiment of the present invention. Fig. 2 shows a fiber-reinforced plastic sheet, and Fig. 2 shows a corrugated sheet;
(3) The figure shows a curved surface forming state. FIG. 2 is a perspective view of a main part of a honeycomb core made of fiber-reinforced plastic according to a conventional example of this type, in which (1) a fiber-reinforced plastic sheet as a base material, (2) a corrugated sheet,
(3) The figure shows a curved surface forming state. FIG. 3 is an explanatory front view of one example of a method of manufacturing a honeycomb core made of fiber-reinforced plastic, wherein FIG. 1A shows a prepared base material, and FIG. FIG. 3 (3) shows a step of stacking and bonding the formed corrugated sheet, and FIG. 4 (4) shows a step of stacking and joining the corrugated sheet. FIG. 4 is a perspective view of the honeycomb core. FIG. 5 is provided for explaining the curved surface forming of the honeycomb core;
(1) FIG. 1 is a schematic perspective view of the whole before curved surface forming, (2) FIG. 2 is a schematic perspective view of the whole after curved surface forming, (3) FIG. 4) FIG. 4 is an explanatory bottom view of the main part after the curved surface is formed. [Description of Signs] 1 Honeycomb core (conventional example) 2 Warp (conventional example) 3 Weft (conventional example) 4 Fiber reinforced plastic sheet (conventional example) 5 Cell wall (conventional example) 6 Cell (conventional example) 7 Corrugated sheet (conventional example) 8 Honeycomb core (of the present invention) 9 Fiber reinforced plastic sheet (of the present invention) 10 Warp yarn (of the present invention) 11 Weft yarn (of the present invention) 12) Rack 13 Corrugating device 14 Corrugated sheet (of the present invention) 15 Adhesive 16 Cell wall (of the present invention) 17 Cell (of the present invention) A Cell end surface B Cell axis C Bending direction D Long side・ Longitudinal direction

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-8-142237 (JP, A) JP-A-7-300378 (JP, A) JP-A-7-266476 (JP, A) JP-A-7- 16963 (JP, A) JP-A-6-312473 (JP, A) JP-A-5-131218 (JP, A) JP 9-500840 (JP, A) JP 7-504621 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B32B 1/00-35/00

Claims (1)

(57) [Claims 1] A cell wall is formed by using a fiber reinforced plastic sheet as a base material, which is obtained by combining, for example, adhering, impregnating, or mixing a resin to a plain woven fiber in which a warp and a weft intersect. A honeycomb core formed of a planar aggregate of a large number of hollow columnar cells partitioned by the cell wall, wherein the fiber reinforced plastic sheet as a base material of the cell wall is:
The fiber direction of the warp or weft is not parallel to the cell end face or cell axis, but is inclined at a predetermined angle, and the honeycomb core is entirely formed into a curved surface so that the cell end face has a predetermined curvature. A honeycomb core made of fiber reinforced plastic.