JPH1158564A - Corrugated core material sandwich panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the rigidity of the overall structure by a reduction in local bending deformation and to improve the safety of the structure by a limit of breakage to a face plate by specifying the interval between an intersection of wavelike ridges at a thickness center line of a core material and a thickness center line of a face plate. SOLUTION: In the corrugated core material sandwich panel comprising two face plates 1 extrusion molded and disposed in parallel and a corrugated core material 2 disposed between the plates 1 and integrally connected to the plates 1, the interval between an intersection of wave-like ridges at a thickness center line of the material 2 and a thickness center line of the plate 1 is set to 1/2 or less of the thickness of the face plate. From a standpoint of dynamics, its offset amount is desirably 0 (mm). It is difficult to always manufacture such a corrugated core material sandwich panel having 0 (mm) of the offset amount due to processability such as of extrusion molding or the like. Incidentally, if the offset amount exceeds 1/2, the rigidity is not improved similarly to a conventional panel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a corrugated core sandwich panel used as a structural member for vehicles, ships, buildings, and the like, and more particularly to a corrugated core sandwich panel having excellent rigidity and strength.

[0002]

2. Description of the Related Art Heretofore, as a corrugated core sandwich panel, there has been used a structure in which a corrugated core (hereinafter, referred to as a web) is disposed between two face plates arranged in parallel. The shape of the connection between the face plate and the web is determined based on restrictions in the manufacturing process and the like. FIG. 6 is a front view showing a conventional corrugated core sandwich panel. In this corrugated core sandwich panel, a corrugated web 2 is arranged between face plates 1a and 1b arranged in parallel. According to such a corrugated core sandwich panel, since the web 2 is arranged between the face plates 1a and 1b in a direction inclined with respect to the normal direction of the face plate and a triangular structure is formed, high rigidity is obtained. be able to.

[0003]

However, the connecting portions of the pair of adjacent webs 2 to the face plates 1a and 1b of the above-described corrugated core sandwich panel are slightly shifted in the longitudinal direction of the face plates 1a and 1b. For this reason, when a load is applied to the vicinity of the connecting portion due to bending deformation or the like, a couple is generated such that the face plate is rotated around one connecting portion of the pair of adjacent webs 2 at the other connecting portion. For this reason, the local bending deformation generated near the connection between the face plate and the web is superimposed on the entire panel, so that the rigidity of the panel is lower than a predetermined value.

In addition, since stress is superimposed due to local bending deformation at the connection between the face plate and the web, when designing a structure using this panel, it is necessary to set a usable load low. , The scope of application is narrowed.

[0005] Further, due to the superposition of local stresses, the stress generated in the web may exceed the stress generated in the face plate. In this case, first, the web becomes the starting point of destruction,
Thereafter, the failure spreads throughout the corrugated core sandwich panel. In order to ensure the safety of the panel, it is necessary to be able to detect the defect when it occurs, but in the panel described above, the web is covered by the face plate, However, it cannot be detected, and it is extremely difficult to prevent collapse before it occurs. For this reason, reducing the stress applied to the web sandwiched between the face plates has been demanded not only to increase the rigidity of the panel but also to ensure safety.

The present invention has been made in view of such a problem, and reduces local bending deformation occurring near a connection portion between a face plate and a web, improves rigidity of the entire structure,
It is an object of the present invention to provide a corrugated core sandwich panel in which a fracture site is limited to a face plate and structural safety is improved.

[0007]

A corrugated core sandwich panel according to the present invention is formed by extrusion molding and has two face plates provided in parallel, and a corrugated core material provided between the face plates. In the corrugated core sandwich panel composed of: the interval between the intersection of the core thickness center line at the wavy ridge and the thickness center line of the face plate is 以下 or less of the thickness of the face plate. There is a feature.

[0008] Another corrugated core sandwich panel according to the present invention is a corrugated core in which two face plates arranged in parallel and a corrugated core material arranged between the face plates are integrated by joining. In the material sandwich panel, a distance between an intersection point of the core thickness in the corrugated peak portion of the core thickness and the thickness center line of the face plate is １ ／ or less of the thickness of the face plate.

In the present invention, the distance between the intersection of the center line of thickness of the core and the center line of thickness of the face plate is not more than 1/2 of the thickness of the face plate. In this case, the local bending deformation can be suppressed, and the fracture site can be limited to the face plate, so that safety can be ensured.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The inventors of the present invention have conducted intensive studies on local bending that occurs in a conventional corrugated core sandwich panel, and have found the following causes. FIG. 7 is a front view showing a connecting portion between a face plate and a web of a conventional corrugated core sandwich panel. As shown in FIG. 7, in this conventional corrugated core sandwich panel, the intersection A between the thickness center lines of the adjacent webs 2 is located far outside the thickness center line of the face plate 1, Due to this displacement, local stress (stress that curves the face plate) is generated. Hereinafter, the displacement between the intersection A and the center line of the thickness of the face plate is referred to as an offset.

Therefore, in the present invention, the amount of offset is set to not more than 1/2 of the thickness of the face plate. From a mechanical point of view, it is desirable that the offset amount be 0 (mm), but the offset amount is always 0 from the viewpoint of workability such as extrusion molding.
It is difficult to produce a (mm) corrugated core sandwich panel. On the other hand, if the amount of offset exceeds １ ／, the rigidity is not improved as in the case of the conventional corrugated core sandwich panel. Therefore, the amount of offset is set to 以下 or less of the thickness of the face plate.

[0012]

EXAMPLES Examples of the present invention will be specifically described below in comparison with comparative examples that fall outside the scope of the claims.

First, a 6N01-T5 material was used to produce an aluminum alloy hollow extruded material having a face plate thickness of 2 mm and a web thickness of 1.5 mm and having the offset shown in Table 1. In Table 1, a positive offset value indicates that the offset is formed outside the thickness center line of the face plate, and a negative offset value indicates that the offset is formed inside the thickness center line of the face plate. It is shown that. FIG. 1 is a front view showing the aluminum alloy hollow extruded shape of Example 4 having an offset of 0.0 (mm), and FIG. 2 is a diagram showing the aluminum alloy hollow extruded shape of Comparative Example 7 having a negative offset. FIG. 3 is a front view showing the aluminum alloy hollow extruded profile of Comparative Example 9 having a positive offset.

[0014]

[Table 1]

Next, with respect to the aluminum alloy hollow extruded shapes of Examples and Comparative Examples, a strain gauge was attached to the face plate and the web, and a three-point bending test was performed under the same conditions.
The results are shown in FIGS. FIG. 4 is a graph showing the relationship between the offset value on the horizontal axis and the amount of deformation of the aluminum alloy hollow extruded profile on the vertical axis, and FIG. 5 shows the offset value on the horizontal axis and the vertical axis on the vertical axis. It is a graph which shows the relationship between both taking a maximum principal stress.

As shown in FIGS. 4 and 5, as the amount of offset (absolute value) increases, the amount of change due to bending and the maximum stress increase. In Examples 1 to 6,
Since the amount of the offset is within the range specified in the present invention,
The amount of deformation due to bending is small and the maximum stress generated is small. Further, the place where the maximum stress occurred was on the face plate.
For this reason, even if a defect due to deterioration over time such as a fatigue crack occurs here, it can be easily detected.

On the other hand, in Comparative Examples 7 to 9, since the amount of offset exceeds the upper limit of the range of the present invention, the amount of deformation due to bending deformation and the generated maximum stress are large. Furthermore,
The location where the maximum stress occurred was near the connection of the web to the face plate. For this reason, if a defect occurs here, it is impossible to detect it, and security cannot be ensured.

[0018]

As described above, according to the present invention,
Since the amount of offset between the face plate and the web is specified appropriately, the weight of the member can be increased without changing the specifications of the member such as the conventionally used panel thickness and the web pitch. Without this, rigidity and strength can be significantly improved. For this reason, specific rigidity and specific strength become extremely high. Therefore, when applied to strength members such as railway vehicles, ships, and building structures, the design load can be set higher, and the applicable range of the corrugated core sandwich panel can be expanded.

[Brief description of the drawings]

FIG. 1 is a front view showing an aluminum alloy hollow extruded profile of Example 4 having an offset of 0.0 (mm).

FIG. 2 is a front view showing an aluminum alloy hollow extruded profile of Comparative Example 7 having a negative offset.

FIG. 3 is a front view showing an aluminum alloy hollow extruded profile of Comparative Example 9 having a positive offset.

FIG. 4 is a graph showing the relationship between the offset value on the horizontal axis and the deformation amount of the aluminum alloy hollow extruded shape on the vertical axis.

FIG. 5 is a graph showing the relationship between the offset value on the horizontal axis and the maximum stress on the vertical axis.

FIG. 6 is a front view showing a conventional corrugated core sandwich panel.

FIG. 7 is a front view showing a connection portion between a face plate and a web of a conventional corrugated core sandwich panel.

[Explanation of symbols]

 1; face plate 2; web

Claims (2)

[Claims] 1. A corrugated core sandwich panel comprising two face plates formed by extrusion and provided in parallel, and a corrugated core material provided between the face plates, wherein the core material is The distance between the intersection of the thickness center line of the wavy peaks and the thickness center line of the face plate is one of the thickness of the face plate.
/ 2 or less, wherein the sandwich panel is a corrugated core material. 2. A corrugated core sandwich panel in which two face plates arranged in parallel and a corrugated core material arranged between the face plates are integrated by joining, a thickness of the core material. A corrugated core sandwich panel, wherein a distance between an intersection of the center line in a wave-shaped peak and a center line of the thickness of the face plate is 以下 or less of a thickness of the face plate.