JP3004370B2 - Multi-layer honeycomb structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer honeycomb structure used as a core of a structural beam member for an aircraft or the like.

[0002]

2. Description of the Related Art Sandwich structural members in which a surface plate is adhered to a core material of a honeycomb core are widely used as structural members for aircraft. As a structural member of this type, there is a structure member using a composite plate in which a prepreg obtained by impregnating a resin into carbon fiber, aramid fiber, or the like is laminated on the surface plate. With this structural member, the mechanical strength can be improved in addition to the significant weight reduction due to the use of the honeycomb core as the core material.

FIG. 8 shows a conventional example of a structural member having a honeycomb core as a core material. This structural member has a structure in which composite material plates 21 and 21 on upper and lower surfaces and composite material plates 22 and 22 on side surfaces are bonded to a honeycomb core 20 which is a core material processed into a columnar body. In such a structural member, when the strength of the core honeycomb core 20 itself is insufficient, for example, an epoxy resin or the like is filled in the cells of the honeycomb core 20 in a portion requiring reinforcement, for example. .

[0004]

However, when the thickness h of the honeycomb core 20 is extremely large with respect to the cell size s of the honeycomb core 20, it is pointed out that there is a problem in the filling and strength of the reinforcing material. Have been. In other words, when the reinforcing material is filled, the resin itself, which is a material, has viscosity and the length of the cell, so that the flow of the resin is easily obstructed. Therefore, when the reinforcing material is the honeycomb core 20
The solidification is completed before the material is uniformly filled in the thickness direction, resulting in an incomplete reinforcement. Regarding strength, the honeycomb core has an absolute thickness h.
There is a characteristic that the shear strength in the thickness direction (the direction of arrow A in FIG. 8) is significantly reduced as is larger. For example, the shear strength of a 4 "thick honeycomb core is reduced by 50% to 70% compared to the shear strength of a honeycomb core having a thickness of 1/2".

Further, there is a problem that the honeycomb core is weak against a load acting from a side surface direction (the direction of arrow B in FIG. 8) and is easily deformed by a pressure applied during processing.

Accordingly, the present invention solves the above-mentioned problems of the prior art, and provides a multilayer honeycomb structure having a high reinforcing effect by filling with a resin and having sufficient strength to withstand loads from various directions. The purpose is to provide.

[0007]

In order to achieve the above object, the present invention provides a unit honeycomb core material in which cells at predetermined portions of a honeycomb core are filled with a reinforcing material via a composite partition plate. It is characterized by being laminated and bonded in multiple layers.

[0008]

According to the present invention, since the thickness of the honeycomb core of each layer is such that the reinforcing material can be evenly filled, the reinforcing effect of the reinforcing material is effective and the strength is sufficient in the thickness direction. In addition, since the thickness of the honeycomb core of each layer can be set to a certain range or less, the shear strength of the honeycomb core of each layer is maintained at a certain level, and even if the thickness of the entire core material increases, the overall Can be suppressed from decreasing. Moreover, the rigidity is increased by the interposition of the partition plate, and a sufficient strength capable of stopping the load from the side surface can be obtained.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the multilayer honeycomb structure according to the present invention will be described with reference to the accompanying drawings. FIG.
Fig. 1 shows a multilayer honeycomb structure according to the present embodiment. This multilayer honeycomb structure is laminated in the thickness direction with a plate-shaped honeycomb core 1 having a predetermined thickness as a unit. It has a multi-layer structure with a composite partition plate 2 interposed therebetween. The configuration of such a multilayer honeycomb structure is specifically shown in FIG.
That is, the honeycomb cores 1 and the partition plates 2 of the respective layers are bonded by the adhesive 3, and the honeycomb cores 1, the adhesive 3, the partition plates 2, the honeycomb cores 1,... It has a multi-layer integrated structure. The honeycomb core 1 of each layer is filled with epoxy resin or the like as a reinforcing material 4 in advance in the cells of the predetermined portions requiring reinforcement. Regarding the thickness of the honeycomb core 1 as a unit, the thicknesses h ₁ , h ₂ , and h of the honeycomb core 1 in each layer correspond to the cell size s.
_{3, h 4} is preferable to below 16s.

In the multilayer honeycomb structure shown in FIGS. 1 and 2, when the number of honeycomb cores 1 is generally n, the number of partition plates 2 interposed therebetween is n-1. Although the structure has been described, the partition plates 2 are bonded to the uppermost and lowermost honeycomb cores 1, that is, the structure in which the number n of the honeycomb cores 1 is n + 1 and the number of the partition plates 2 stacked alternately is n + 1. It may be.

Next, FIG. 3 is a view showing an example in which the honeycomb structure of FIG. 1 is applied as a core material to a structural beam member, FIG. 4 shows a longitudinal section, and FIG. 5 shows a transverse section. FIG. In this beam member, a multilayer honeycomb structure in which five partition plates 2 are sandwiched between each layer of a six-layer honeycomb core 1 is used as a core material. It is formed by bonding the side plates 6 and 6 having a U-shaped cross section on the side surfaces of the upper and lower flat composite material plates 5 and 5 which have been hardened and processed into a predetermined shape. In this beam member,
A joint hole 7 is cut out at the center side of the structure so that another structural member can be joined. In this beam member, the reinforcing material 4 is filled in the cells of the honeycomb core 1 in each layer for reinforcement around the portion where the load is concentrated, that is, around the support end at both ends and the hole 7 at the center. . By using the multilayer honeycomb structure as a core material in this manner, the thickness of the honeycomb core 1 of each layer is such that the reinforcing material 4 can be evenly filled, and the reinforcing effect of the reinforcing material 4 is effective. It has sufficient strength in the direction. Further, by setting the thickness of the honeycomb core 1 of each layer to a certain range or less, the shear strength of the honeycomb core 1 of each layer can be maintained at a certain level.
Even if the thickness of the core material as a whole increases, a decrease in the overall strength can be suppressed. In addition, the rigidity is increased by the interposition of the partition plate 2, and a sufficient strength capable of stopping the load from the side surface can be obtained.

Next, the beam member whose cross section is shown in FIG. 6 and whose cross section is shown in FIG. The core material is used. In this embodiment, the core material as described above and the surface plate of the composite material are simultaneously bonded and cured. That is, from the bottom, the partition plate 2, the adhesive, the honeycomb core 1, the adhesive, the partition plate 2, the adhesive, the honeycomb core 1
And the prepreg, which is the material of the surface plate 8, is wound around the entire core material. Then, while being evacuated by a vacuum bag method, it is bonded and cured while being pressurized and heated in an autoclave.

In such a beam member, in addition to being able to bear the load in the width direction by the partition plate 2, deformation of each cell of the honeycomb core 1 is prevented by the reinforcing material 4 filled with the cells 1 in both side regions. Will be done.

[0014]

As is apparent from the above description, according to the present invention, a unit honeycomb core material in which a reinforcing material is filled in a cell at a predetermined portion of a honeycomb core is multilayered through a composite partition plate. Since the honeycomb core is laminated and bonded, the thickness of the honeycomb core can be set to a thickness at which the reinforcing material is uniformly filled in the cells. And in the structural member using this multilayer honeycomb structure as a core material of a structural member, the thickness of the honeycomb core of each layer can be set to a certain range or less. Also, it is possible to suppress a decrease in strength as a whole. Moreover, the rigidity is increased by the interposition of the partition plate, and a sufficient strength capable of stopping the load from the side surface can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a multilayer honeycomb structure according to the present invention.

FIG. 2 is a perspective view showing a stacked state of the multilayer honeycomb structure of FIG. 1;

FIG. 3 is a perspective view showing an example in which the multilayer honeycomb structure of FIG. 1 is applied to a core of a structural beam member.

FIG. 4 is a cross-sectional view of the structural beam member of FIG. 3 taken along line CC.

FIG. 5 is a sectional view taken along line DD of the structural beam member of FIG. 3;

FIG. 6 is a perspective view of another example of a structural beam member in which the present invention is applied to a core material.

FIG. 7 is a sectional view taken along line EE of the structural beam member of FIG. 6;

FIG. 8 is a perspective view of a structural member having a conventional honeycomb core as a core material.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Honeycomb core 2 Partition plate 3 Adhesive 4 Reinforcement material 5 Surface plate 6 Surface plate

Claims (1)

(57) [Claims] 1. A multilayer honeycomb structure, wherein unit honeycomb core materials in which cells at predetermined portions of a honeycomb core are filled with a reinforcing material are laminated and bonded in multiple layers via a composite partition plate. .