WO2024204331A1 - Structural component - Google Patents

Abstract

A structural component (100, 200) is provided with a top plate (10) and side walls (21, 22). The structural component (100, 200) includes a curved region (30). When viewed from the side wall (21, 22) side, the curved region (30) is curved such that the top plate (10) side is on the inside of the curve and the opposite side to the top plate (10) is on the outside of the curve. In the curved region (30), the side walls (21, 22) are connected by the top plate (10) on the inside of the curve. The curved region (30) is open on the outside of the curve. When the curved region (30) is viewed in a cross section, ends (211, 221) of the top plate (10) in each of the side walls (21, 22) are disposed inside the structural component (100, 200) with respect to boundary portions (212, 222) between the side walls (21, 22) and the top plate (10). When the curved region (30) is viewed in the cross section, the total of the lengths of the side walls (21, 22) is greater than the length of the top plate (10).

Description

Structural parts

This disclosure relates to structural components.

For example, structures such as the body of an automobile are formed using structural parts. Structural parts are required to be durable against input loads.

For example, Patent Document 1 discloses a suspension arm for automobiles. The suspension arm in Patent Document 1 includes a plate-shaped main body and pipe-shaped reinforcing parts provided on both side edges of the main body. Patent Document 1 states that this structure increases the second moment of area about an axis that passes through the centroid of the main body and is perpendicular to the main body, thereby providing the suspension arm with sufficient rigidity to withstand bending loads.

For example, Patent Document 2 discloses a cross member for automobiles. The cross member in Patent Document 2 comprises a web folded into a saddle shape, a pair of side walls provided on both side edges of the web, and flanges provided at the tip of each side wall. In this cross member, the width of the web gradually increases from both longitudinal ends of the web toward the folded portion. Patent Document 2 describes that by making the flange-side tips of the pair of side walls at both longitudinal ends of the web more open than the base end of the web, it is possible to improve the side impact strength when the cross member is connected to a side member for use.

Japanese Patent Application Publication No. 8-188022 JP 2012-111377 A

Some structural parts, such as rear upper arms, which are one type of suspension arm for automobiles, include curved regions when viewed from the side. Such structural parts often have a closed cross-sectional structure. For example, structural parts with a closed cross-sectional structure called a "monaka structure" are formed by arranging two concave members facing each other and joining them by arc welding. However, since rust is likely to occur at arc welded parts, measures must be taken to prevent rust. In addition, performing arc welding in the manufacturing process of structural parts can increase the manufacturing costs of the structural parts.

If structural components have an open cross-section structure with no arc welds, rusting at the arc welds can be avoided and the manufacturing costs of the structural components can be reduced. However, if structural components are simply made to have an open cross-section structure, there is a problem in that the rigidity of the structural components decreases, and the reaction force of the structural components to the input load becomes small.

The objective of this disclosure is to provide a structural component that can exert a high reaction force against an input load despite having an open cross-section structure.

The structural component according to the present disclosure includes a top plate and two side walls. The two side walls are arranged to face each other. The two side walls are each continuous with the top plate. The structural component includes a curved region. When viewed from the side wall side, the curved region is curved with the top plate side being the inside of the curve and the opposite side of the top plate being the outside of the curve. In the curved region, the two side walls are connected by the top plate on the inside of the curve. The curved region opens on the outside of the curve. When the curved region is viewed in cross section, the ends of each of the two side walls that are located on the opposite side of the top plate are arranged inside the structural component with respect to the boundary between the side wall and the top plate. When the curved region is viewed in cross section, the sum of the lengths of the two side walls is greater than the length of the top plate.

The structural components disclosed herein are capable of exerting a high reaction force against an input load, despite having an open cross-section structure.

FIG. 1 is a perspective view that illustrates a structural component according to a first embodiment. FIG. 2 is a side view that diagrammatically illustrates the structural component according to the first embodiment. FIG. 3 is a cross-sectional view of the structural component shown in FIGS. FIG. 4 is a cross-sectional view of a structural component according to a second embodiment. FIG. 5 is a cross-sectional view of a structural component according to a modified example of the second embodiment. FIG. 6 is a graph showing the relationship between the width reduction rate of a structural part and the reaction force at the time of a stroke of 20 mm. FIG. 7 is a graph showing the relationship between the width reduction rate of a structural part and the maximum reaction force.

The structural component according to the embodiment includes a top plate and two side walls. The two side walls are arranged to face each other. The two side walls are each continuous with the top plate. The structural component includes a curved region. When viewed from the side wall side, the curved region is curved with the top plate side being the inside of the curve and the opposite side of the top plate being the outside of the curve. In the curved region, the two side walls are connected by the top plate on the inside of the curve. The curved region opens on the outside of the curve. When the curved region is viewed in cross section, the ends of each of the two side walls that are located on the opposite side of the top plate are arranged inside the structural component with respect to the boundary between the side wall and the top plate. When the curved region is viewed in cross section, the sum of the lengths of the two side walls is greater than the length of the top plate (first configuration).

The structural component according to the first configuration includes a curved region that is curved when viewed from the side wall side of the structural component. The curved region has an open cross-sectional structure in which two side walls are connected by a top plate on the inside of the curve, while the outside of the curve is open. When a compressive load that compresses both ends is input to the structural component according to the first configuration, compressive deformation occurs at the top plate on the inside of the curve and at the boundary between the top plate and each side wall, and tensile deformation occurs at the end of each side wall on the outside of the curve. At this time, the tensile deformation at the end of each side wall becomes the driving force and contact occurs between the both side walls. More specifically, when tension is applied to the end of both side walls in the longitudinal direction of the structural component, the side walls are tilted so that the cross section of the structural component is reduced and the deformation of the structural component is made easier. In the first configuration, in the cross-sectional view of the curved region, the end of both side walls is preliminarily positioned inside the structural component compared to the boundary between the top plate and both side walls. Therefore, when tension is applied to the end of both side walls in the longitudinal direction of the structural component, the end of both side walls is more likely to move inside the structural component. When the ends of both side walls move inwardly of the structural component, for example, the ends of both side walls come into contact with each other, and a force pressing the both side walls against each other acts on the curved region of the structural component. In this case, even after the reaction force of the structural component reaches its peak in response to the input compressive load, the decrease in the reaction force is more likely to be suppressed. Therefore, the structural component can exert a high reaction force even in the later stages of deformation.

In this way, the structural component according to the first configuration can exert a high reaction force against the input load, despite having an open cross-section structure.

In the structural component of the first configuration, when the curved region is viewed in cross section, the direction in which a straight line connecting the boundary between one of the two side walls and the top plate and the boundary between the other side wall and the top plate extends is defined as the width direction of the structural component, and the length of this straight line is defined as the width of the top plate. The distance in the width direction from the end of one side wall to the end of the other side wall may be 99.5% or less of the width of the top plate (second configuration).

In the structural component of the second configuration, the widthwise distance from the end of one side wall to the end of the other side wall may be 85.0% or more of the width of the top plate (third configuration).

The structural component according to any one of the first to third configurations may further include a flange. The flange is continuous with at least one of the two side walls on the opposite side of the top plate. The flange protrudes from at least one of the side walls in a direction intersecting the side wall. It is preferable that the flange extends along the curved region, passing through the bottom of the curved region, on the outside of the curve (fourth configuration).

In the structural component of the fourth configuration, a flange is provided on one or both ends of the two side walls at least at the bottom position of the curved region. This increases the rigidity of the curved region of the structural component, thereby increasing the peak of the reaction force against the compressive load.

In the structural component according to the fourth configuration, a flange may be provided on each of the two side walls (fifth configuration).

In a structural component according to any one of the first to fifth configurations, when the curved region is viewed in cross section, the two side walls may be arranged symmetrically with respect to the center of the top plate (sixth configuration).

In the sixth configuration, two side walls are provided symmetrically with respect to the center of the top plate in the cross section of the curved region of the structural component. In this case, when a compressive load is applied to the structural component, torsional deformation is less likely to occur in the curved region.

Below, an embodiment of the present disclosure will be described with reference to the drawings. In each drawing, the same or equivalent components are given the same reference numerals, and the same description will not be repeated.

[First embodiment]
(Structural component configuration)
Fig. 1 is a perspective view that typically shows a structural component 100 according to a first embodiment. Fig. 2 is a side view that typically shows the structural component 100. The structural component 100 is used, for example, in the body of an automobile. The structural component 100 may be, for example, a chassis component such as a suspension arm. In this embodiment, an example will be described in which the structural component 100 is an upper arm, which is a type of suspension arm.

Referring to Figures 1 and 2, the structural component 100 includes a top plate 10 and side walls 21 and 22.

When the structural component 100, which is the upper arm, is attached to the vehicle, the top plate 10 extends substantially or generally in the left-right direction of the vehicle. Hereinafter, the direction in which the top plate 10 extends is referred to as the longitudinal direction of the structural component 100.

The side walls 21, 22 are arranged to face each other. The side wall 21 is continuous with the top plate 10. The side wall 22 is continuous with the top plate 10 on the opposite side of the side wall 21. The side walls 21, 22 extend in the longitudinal direction of the structural component 100 along the top plate 10.

The structural component 100 includes a curved region 30. When viewed from the side wall 21 side, the curved region 30 is curved with the top plate 10 side being the inside of the curve and the opposite side of the top plate 10 being the outside of the curve. When viewed from the side wall 22 side opposite the side wall 21, the curved region 30 is also curved with the top plate 10 side being the inside of the curve and the opposite side of the top plate 10 being the outside of the curve. In the curved region 30, the side walls 21 and 22 are connected by the top plate 10 on the inside of the curve. On the other hand, the curved region 30 is open on the outside of the curve. In other words, on the outside of the curve of the curved region 30, the structural component 100 is divided and the side wall 21 and the side wall 22 are separated.

When the structural component 100 is used in the body of an automobile as in this embodiment, the curved region 30 is curved, for example, so as to be concave downward when the structural component 100 is attached to the automobile. The curved region 30 extends in the longitudinal direction of the structural component 100 with a radius of curvature of, for example, 400 mm or less. The curved region 30 may extend in the longitudinal direction of the structural component 100 with a radius of curvature of, for example, 200 mm or less. It is preferable that the curved region 30 extends in the longitudinal direction of the structural component 100 with a radius of curvature of, for example, 150 mm or less. The radius of curvature of the curved region 30 is, for example, 20 mm or more, and preferably 50 mm or more. The radius of curvature in this case is the radius of curvature of the inner side of the curve of the curved region 30.

Mounting portions 41, 42 are provided at both longitudinal ends of the structural component 100. The mounting portions 41, 42 are portions for mounting the structural component 100 to other components. The top plate 10 extends from the vicinity of one mounting portion 41 to the vicinity of the other mounting portion 42. The mounting portions 41, 42 may be, for example, burring portions formed on the side walls 21, 22. In this case, bushings 51, 52 are press-fitted into the mounting portions 41, 42, respectively. However, the form of the mounting portions 41, 42 is not limited to this.

Figure 3 is a diagram showing a cross section (transverse section) of the structural component 100 when cut along a plane perpendicular to the longitudinal direction. Figure 3 shows the III-III section of Figure 2, i.e., the transverse section of the structural component 100 at the position of the bottom 31 of the curved region 30.

Referring to FIG. 3, the tabletop 10 includes a tabletop body 11 and ridge portions 121 and 122. The tabletop body 11 has a substantially flat shape when viewed in a cross section of the structural component 100. The ridge portions 121 and 122 are provided continuously on both side edges of the tabletop body 11. The ridge portion 121 is a corner portion between the tabletop body 11 and one side wall 21. The ridge portion 122 is a corner portion between the tabletop body 11 and the other side wall 22. The ridge portions 121 and 122 have, for example, a substantially arc shape when viewed in a cross section of the structural component 100.

The side walls 21, 22 are provided contiguous to the ridges 121, 122 of the top plate 10, respectively. In the curved region 30, the ends 211, 221 of the side walls 21, 22 located on the opposite side of the top plate 10 are open ends. That is, the structural component 100 has an open cross-sectional structure at least in the range of the curved region 30. The structural component 100 can also have an open cross-sectional structure over the entire or almost entire longitudinal direction. An open cross-sectional structure means that the end 211 of the side wall 21 and the end 221 of the side wall 22 are arranged apart, and the structural component 100 itself does not have a continuous structure on the end 211, 221 side.

When the curved region 30 is viewed in cross section, the ends 211, 221 of the side walls 21, 22 are positioned inside the structural component 100 relative to the boundaries 212, 222 between the side walls 21, 22 and the top plate 10. When the direction in which the straight line connecting the boundaries 212, 222 extends is the width direction of the structural component 100 in the cross section of the curved region 30, the ends 211, 221 of the side walls 21, 22 are located between the boundaries 212 and 222 in the width direction of the structural component 100.

In this embodiment, the side walls 21 and 22 are each bent midway, so that the ends 211 and 221 are positioned inward in the width direction of the structural component 100 from the boundaries 212 and 222. However, the method of positioning the ends 211 and 221 inward in the width direction of the structural component 100 from the boundaries 212 and 222 is not limited to this. For example, the side walls 21 and 22 may be inclined overall with respect to a direction perpendicular to the width direction in a cross-sectional view of the structural component 100, so that the ends 211 and 221 are positioned inward in the width direction of the structural component 100 from the boundaries 212 and 222. Also, for example, the side walls 21 and 22 may be curved in a cross-sectional view of the structural component 100 so that the ends 211 and 221 are positioned inward in the width direction of the structural component 100 from the boundaries 212 and 222.

The ends 211, 221 of the side walls 21, 22 are not folded back toward the top plate 10 side with respect to the other parts of the side walls 21, 22. That is, in the cross section of the curved region 30, the angle θ ₁ that the end 211 makes with respect to the imaginary line VL ₁ that passes through the boundary 212 between the top plate 10 and the side wall 21 and is perpendicular to the width direction of the structural component 100 is less than 90°. Similarly, in the cross section of the curved region 30, the angle θ ₂ that the end 221 makes with respect to the imaginary line VL ₂ that passes through the boundary 222 between the top plate 10 and the side wall 22 and is perpendicular to the width direction of the structural component 100 is less than 90°. The angles θ _{1, θ 2 are preferably 30° or less. Each of the angles θ 1 , θ 2 may be} greater than 0°, but may be 5° or more. When the side wall 21 is curved in the cross-sectional view of the curved region 30, the angle _θ1 is the angle between a tangent to the outer surface of the side wall 21 at the tip of the end 211 and a virtual line _VL1 . When the side wall 22 is curved in the cross-sectional view of the curved region 30, the angle _θ2 is the angle between a tangent to the outer surface of the side wall 22 at the tip of the end 221 and a virtual line _VL2 .

In the cross-sectional view of the curved region 30, the direction in which a straight line connecting the boundary 212 between the side wall 21 and the top plate 10 and the boundary 222 between the side wall 22 and the top plate 10 extends is the width direction of the structural component 100, and the length of the straight line is the width _W0 of the top plate 10. The linear distance _L0 in the width direction from the end 211 of the side wall 21 to the end 221 of the side wall 22 is shorter than the width _W0 of the top plate 10. In other words, the width of the structural component 100 is reduced on the outer side of the curve of the curved region 30 compared to the inner side of the curve. In the example of FIG. 3, the width _W0 of the top plate 10 is the linear distance between the boundaries 212, 212 on the outer surface of the structural component 100, and the distance _L0 between the ends 211, 221 of the side walls 21, 22 is the width direction distance between the ends 211, 221 on the outer surface of the structural component 100. The distance _L0 between the ends 211, 221 of the side walls 21, 22 is shorter than the width _W0 of the top plate 10 in the range including at least the bottom portion 31 (FIG. 2) of the curved region 30. The distance _L0 between the ends 211, 221 may be shorter than the width _W0 of the top plate 10 only in the curved region 30, or may be shorter than the width _W0 over the entire or almost entire structural component 100.

The distance _L0 between the ends 211, 221 of the side walls 21, 22 is, for example, 99.5% or less of the width _W0 of the top plate 10, and preferably 98.0% or less of the width _W0 of the top plate 10. The distance _L0 between the ends 211, 221 of the side walls 21, 22 may be 85.0% or more of the width _W0 of the top plate 10. In other words, the width reduction rate of the structural component 100 in the curved region 30 is, for example, 0.5% or more, and preferably 2.0% or more. The width reduction rate may be 15.0% or less. In the cross section of the curved region 30, when the length in the width direction of the structural component 100 from the boundary 212 between the side wall 21 and the top plate 10 to the end 211 is _L1 , and the length in the width direction of the structural component 100 from the boundary 222 between the side wall 22 and the top plate 10 to the end 221 is _L2 , the width reduction rate (%) is calculated by 100 × ( _L1 + _L2 ) ÷ _W0 . The ratio (%) of the distance _L0 between the ends 211, 221 of the side walls 21, 22 to the width _W0 of the top plate 10 is the value obtained by subtracting the width reduction rate from 100.

In the cross-sectional view of the curved region 30, the sum SH of the lengths (heights) _H1 , _H2 of the side walls 21, 22: _H1 + _H2 is greater than the width _W0 of the tabletop 10. The height _H1 of the side wall 21 is the linear distance from the boundary ₂₁₂ between the side wall 21 and the tabletop 10 to the end 211 in the cross-section of the curved region 30. The height _H2 of the side wall 22 is the linear distance from the boundary 222 between the side wall 22 and the tabletop 10 to the end 221 in the cross-section of the curved region 30. The sum _SH of the heights _H1 , _H2 of the side walls 21, 22 may be more than 100% of the width _W0 of the tabletop ₁₀ , but is preferably 200% or more, and more preferably 400% or more. The sum _SH of the heights _H1 , _H2 of the side walls 21, 22 is greater than the width _W0 of the tabletop 10 at least in the area where the width of the structural component 100 is smaller on the outer side of the curve compared to the inner side of the curve. The sum _SH of the heights _H1 , _H2 of the side walls 21, 22 may be greater than the width _W0 of the tabletop 10 only in the curved region 30, or may be greater than the width _W0 over the entire length of the tabletop 10.

In this embodiment, when the curved region 30 is viewed in cross section, the side walls 21 and 22 are provided symmetrically with respect to the center of the tabletop 10. More specifically, in the cross section of the curved region 30, the side walls 21 and 22 are provided symmetrically with respect to the width center line CL of the tabletop 10, which passes through the midpoint of a line connecting the boundary portion 212 of the side wall 21 with the tabletop 10 and the boundary portion 222 of the side wall 22 with the tabletop 10 and is perpendicular to the line. Therefore, the gap between the end portion 211 of the side wall 21 and the end portion 221 of the side wall 22 is also located on the width center line CL of the tabletop 10. It is preferable that the side walls 21 and 22 are symmetrical with respect to the center of the tabletop 10 over at least the entire length of the curved region 30.

(effect)
The structural component 100 according to this embodiment includes a curved region 30 that is curved when viewed from the side walls 21 and 22. The curved region 30 has an open cross-sectional structure that opens on the outside of the curve. In other words, in the curved region 30, the ends 211 and 221 of the side walls 21 and 22 are spaced apart from each other. When a compressive load that compresses the mounting portions 41 and 42 is input to the structural component 100, compressive deformation occurs in the top plate 10 on the inside of the curve and in the boundaries 212 and 222 between the top plate 10 and the side walls 21 and 22, and tensile deformation occurs in the ends 211 and 221 of the side walls 21 and 22 on the outside of the curve. At this time, the tensile deformation of the ends 211 and 221 serves as a driving force to deform the side walls 21 and 22 in a direction approaching each other. More specifically, when tension is applied to the ends 211, 221 of the side walls 21, 22 in the extension direction, the side walls 21, 22 incline in a direction that reduces the cross section of the structural component 100 so that the structural component 100 can be easily deformed. In this embodiment, in the cross section of the curved region 30, the ends 211, 221 of the side walls 21, 22 are pre-positioned on the inner side in the width direction of the structural component 100 compared to the boundaries 212, 222 between the top plate 10 and the side walls 21, 22, so that the ends 211, 221 can easily move inward in the width direction of the structural component 100. Therefore, when a compressive load is input to the structural component 100, the side walls 21, 22 incline so that the ends 211, 221 move inward in the width direction of the structural component 100. When no inclusion is present between the ends 211, 221, the ends 211, 221 come into direct contact with each other, and the cross section of the curved region 30 becomes a pseudo-closed cross section, causing a force to press the side walls 21, 22 against each other. When an inclusion is present between the ends 211, 221, the ends 211, 221 come into contact with the inclusion from both sides, causing a force to press the side walls 21, 22 against each other. This prevents the reaction force from decreasing even after the reaction force of the structural component 100 against the compressive load reaches its peak. Therefore, the structural component 100 can exert a high reaction force even in the later stages of deformation.

Thus, the structural component 100 according to this embodiment has an open cross-sectional structure in which the end 211 of the side wall 21 and the end 221 of the side wall 22 are spaced apart in the width direction, yet can exert a high reaction force against an input compressive load. In the structural component 100 according to this embodiment, the opening between the side walls 21 and 22 is not blocked. However, the opening between the side walls 21 and 22 may be blocked as long as a force can be applied that pushes the side walls 21 and 22 against each other when a compressive load is input to the structural component 100. For example, the side walls 21 and 22 may be connected by a component separate from the structural component 100.

In the structural component 100 according to this embodiment, the distance _L0 between the ends 211, 221 of the side walls 21, 22 is, for example, 99.5% or less of the width _W0 of the top plate 10, and preferably 98.0% or less. In this case, the structural component 100 is more likely to exert a high reaction force in the later stage of deformation. The distance _L0 between the ends 211, 221 of the side walls 21, 22 is preferably 85.0% or more of the width _W0 of the top plate 10. In this case, when a compressive load is input to the structural component 100, not only the reaction force in the later stage of deformation but also the peak reaction force can be increased.

In this embodiment, when the curved region 30 is viewed in cross section, the side walls 21 and 22 are arranged symmetrically with respect to the center of the top plate 10. This prevents torsional deformation in the curved region 30 from occurring when a compressive load is applied to the structural component 100.

However, in the cross section of the curved region 30, the side walls 21, 22 do not necessarily have to be symmetrical with respect to the center of the top plate 10. The side walls 21, 22 only need to be pre-positioned inward in the width direction of the structural component 100 compared to the boundaries 212, 222 with the top plate 10 so that deformation can occur in which the ends 211, 221 approach each other when a compressive load is input to the structural component 100.

[Second embodiment]
4 is a cross-sectional view of a structural component 200 according to the second embodiment. The structural component 200 according to this embodiment has basically the same configuration as the structural component 100 according to the first embodiment (FIGS. 1 to 3). However, the structural component 200 differs from the structural component 100 according to the first embodiment in that the structural component 200 includes flanges 61 and 62.

Referring to FIG. 4, the flange 61 is continuous with one side wall 21 on the opposite side of the top plate 10. That is, the flange 61 is provided continuous with the end portion 211 of the side wall 21. The flange 61 protrudes from the side wall 21 in a direction intersecting with the side wall 21. In this embodiment, the flange 61 protrudes from the end portion 211 of the side wall 21 toward the outside of the structural component 200.

The flange 62 is continuous with the other side wall 22 on the opposite side of the top plate 10. That is, the flange 62 is provided continuous with the end portion 221 of the side wall 22. The flange 62 protrudes from the side wall 22 in a direction intersecting with the side wall 22. In this embodiment, the flange 62 protrudes from the end portion 221 of the side wall 22 toward the outside of the structural component 200. The flange 62 protrudes toward the opposite side from the flange 61.

The flanges 61, 62 extend along the curved region 30, passing through the bottom 31 (FIG. 2), outside the curvature of the curved region 30. That is, the flanges 61, 62 extend along the ends 211, 221 of the side walls 21, 22 in an area that includes at least the bottom 31 of the curved region. The flanges 61, 62 may extend along the ends 211, 221 of the side walls 21, 22 over the entire length of the curved region 30. The flanges 61, 62 may extend along the ends 211, 221 of the side walls 21, 22, for example, up to the vicinity of the mounting portions 41, 42 (FIGS. 1 and 2).

In this embodiment, when the curved region 30 is viewed in cross section, the flanges 61, 62 are provided symmetrically with respect to the width center line CL of the tabletop 10. In the example of FIG. 4, the flanges 61, 62 are substantially parallel to the tabletop body 11 in cross section of the curved region 30. However, the flanges 61, 62 may be inclined with respect to the tabletop body 11 in cross section of the curved region 30.

The length (width) of the flanges 61, 62 in the width direction of the structural component 200 may be constant over the entire length of the flanges 61, 62, or may vary along the extension direction of the flanges 61, 62. For example, the width of the flanges 61, 62 may be larger at the bottom 31 of the curved region 30 (FIG. 2) than at both ends of the structural component 200 in the longitudinal direction. In this case, it is preferable that the width of the flanges 61, 62 is maximum at the bottom 31 of the curved region 30. It is also preferable that the width of the flanges 61, 62 gradually decreases from the bottom 31 of the curved region 30 toward both ends of the structural component 200 in the longitudinal direction. However, the width of the flanges 61, 62 may suddenly change at any position in the longitudinal direction of the structural component 200.

In the case where the flange 61 is provided continuously on the side wall 21 as in the present embodiment, when measuring the lengths _L0 , _L1 and height _H1 related to the side wall 21, the end 211 of the side wall 21 is set to the end of the R of the corner portion between the side wall 21 and the flange 61 on the side wall 21 side. Similarly, in the case where the flange 62 is provided continuously on the side wall 22, when measuring the lengths _L0 , _L2 and height _H2 related to the side wall 22, the end 221 of the R of the corner portion between the side wall 22 and the flange 62 on the side wall 22 side is set to the end of the R. As in the first embodiment, the lengths _L0 , _L1 , _L2 and heights _H1 , _H2 related to the side walls 21 and 22, and the width _W0 of the top plate are measured on the outer surface of the structural component 200.

In the structural component 200 according to this embodiment, as in the first embodiment, when a compressive load is applied between the mounting portions 41, 42, the ends 211, 221 of the side walls 21, 22 come into direct or indirect contact with each other, causing a pushing force to act on the side walls 21, 22, and a high reaction force can be exerted even in the later stages of deformation. In addition, the structural component 200 is provided with flanges 61, 62, which increases the rigidity of the structural component 200 against compressive loads. Therefore, despite having an open cross-section structure, the structural component 200 can exert a high peak reaction force when a compressive load is applied.

In this embodiment, when the curved region 30 is viewed in cross section, the flanges 61, 62 are arranged symmetrically with respect to the center of the tabletop 10. This makes it difficult for torsional deformation to occur in the curved region 30 when a compressive load is input to the structural component 200. However, the flanges 61, 62 do not necessarily have to be arranged symmetrically with respect to the center of the tabletop 10.

The structural component 200 according to this embodiment has flanges 61, 62 that are continuous with the side walls 21, 22 on the opposite side of the top plate 10. However, the structural component 200 does not necessarily have to have either of the flanges 61, 62.

In this embodiment, the flanges 61, 62 protrude from the side walls 21, 22 toward the outside of the structural component 200. However, as shown in FIG. 5, the flanges 61, 62 can also protrude from the side walls 21, 22 toward the inside of the structural component 200. Alternatively, one of the flanges 61, 62 can protrude toward the outside of the structural component 200, and the other of the flanges 61, 62 can protrude toward the inside of the structural component 200. When the structural component 200 has only one of the flanges 61, 62, the flange can protrude toward the outside of the structural component 200 or can protrude toward the inside of the structural component 200.

　Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above embodiments, and various modifications are possible without departing from the spirit of the present disclosure.

The present disclosure will be explained in more detail below with reference to examples. However, the present disclosure is not limited to the following examples.

In order to confirm the effects of the present disclosure, a numerical analysis was performed using commercially available structural analysis software (Abaqus, Dassault Systèmes) on a structural component having the same shape as the structural component 100 (FIGS. 1 to 3) according to the first embodiment. In this analysis, the reaction force when a compressive load that compresses the mounting parts (between fastening points) of the structural component was input, more specifically, the reaction force when the displacement stroke in the load direction was 20 mm (at 20 mm stroke) was evaluated as the reaction force in the later stage of deformation. The maximum reaction force (peak reaction force) when a compressive load was input was also evaluated. For comparison, a similar analysis was performed on a structural component having a normal open cross-section structure.

FIG. 6 is a graph showing the results of this analysis. FIG. 6 shows the relationship between the width reduction rate (%): 100×(L ₁ +L ₂ )÷W ₀ described in the first embodiment and the reaction force (kN) at the time of a 20 mm stroke. As can be seen from FIG. 6, in the structural part (Example) having an open cross-sectional structure in which the ends of both side walls are separated from each other and the ends of both side walls are located on the inner side in the width direction relative to the boundary between the side wall and the top plate, the reaction force at the time of a 20 mm stroke was larger than that of a normal structural part (Comparative Example) having an open cross-sectional structure but the ends of both side walls are located at the same position in the width direction as the boundary between the side wall and the top plate. More specifically, it was confirmed that in each of the Examples in which the width reduction rate in the curved region of the structural part was 0.5% or more, the reaction force at the time of a 20 mm stroke was significantly larger than that of the Comparative Example in which the width reduction rate was 0.0%. In particular, when the width reduction rate was 2.0% or more, the reaction force at the time of a 20 mm stroke was significantly increased compared to the Comparative Example. Therefore, it can be said that the structural component according to the embodiment exerts a high reaction force in the later stage of deformation, despite having an open cross-sectional structure.

FIG. 7 is also a graph showing the results of this analysis. In FIG. 7, the relationship between the width reduction rate (%): 100×(L ₁ +L ₂ )÷W ₀ and the maximum reaction force (kN) is shown. As shown in FIG. 7, for some examples, in addition to the reaction force at the time of a stroke of 20 mm, the maximum reaction force was also larger than that of the comparative example. More specifically, when the width reduction rate was 15.0% or less, the maximum reaction force was larger than that of the comparative example in which the width reduction rate was 0.0%. Therefore, in order to increase the maximum reaction force as well as the reaction force at the later stage of deformation, it is preferable that the width reduction rate is 15.0% or less.

On the other hand, when a similar analysis was performed on a structural component with flanges on the ends of the side walls, such as the structural component 200 of the second embodiment, the maximum reaction force of this structural component increased by nearly 20% compared to the comparative example, even though the width reduction rate was 50%. Therefore, it was confirmed that a high maximum reaction force can be obtained by providing flanges on the side walls in a structural component that has an open cross-sectional structure and in which the ends of both side walls are located widthwise inward relative to the boundary between the side walls and the top plate.

100, 200: structural part 10: top plate 21, 22: side wall 211, 221: end portion 212, 222: boundary portion 30: curved region 31: bottom portion 61, 62: flange

Claims (6)

A structural part,
The top plate and
Two side walls arranged to face each other and each continuing to the top plate;
Equipped with
The structural component is curved, as viewed from the side wall side, with the top plate side being the inside of the curve and the opposite side of the top plate being the outside of the curve, and the two side walls are connected by the top plate on the inside of the curve and are open on the outside of the curve;
Including,
A structural component, wherein when the curved region is viewed in cross section, the ends of each of the two side walls that are located opposite the top plate are positioned inside the structural component relative to the boundary between the side wall and the top plate, and the sum of the lengths of the two side walls is greater than the length of the top plate. 2. A structural component according to claim 1,
A structural component, wherein, when viewing the curved region in cross section, the direction in which a straight line connecting the boundary between one of the two side walls and the top plate and the boundary between the other side wall and the top plate extends is defined as the width direction of the structural component, and the length of the straight line is defined as the width of the top plate, and the width direction distance from the end of the one side wall to the end of the other side wall is 99.5% or less of the width of the top plate. A structural component according to claim 2,
A structural component, wherein the distance is greater than or equal to 85.0% of the width of the top plate. 2. The structural component of claim 1, further comprising:
a flange that is continuous with at least one of the two side walls on the opposite side of the top plate and protrudes from the at least one side wall in a direction intersecting the side wall;
Equipped with
The flange extends along the curved region, through a bottom of the curved region, outside the curve. A structural component according to claim 4,
A structural component, wherein the flange is provided on each of the two side walls. A structural component according to any one of claims 1 to 5,
A structural component, wherein when the curved region is viewed in cross section, the two side walls are arranged symmetrically with respect to the center of the top plate.

Images