JP5533705B2 - Structure - Google Patents

Description

  The present invention relates to a structure that reduces bending of a member with respect to a load from a bracket.

  For steel structures such as automobiles, construction machinery, bridges, and building structures, in order to reduce weight or size, high-strength steel called high-tensile material is used to make the plate thickness or cross-sectional area of the member. Need to be small. However, if the thickness or cross-sectional area of the member is reduced, the rigidity of the member is reduced, and deformation with respect to external force, that is, flexure, increases, which makes it impossible to secure the safety of the steel structure. And the emergence of technology that achieves both reduction in deflection.

  Several techniques have been proposed for reducing the bending of the structure, that is, for improving the rigidity of the structure. For example, a technique for making the point of application of the pipe having a circular cross section into a rhombic cross section for the purpose of improving torsional rigidity. Patent Document 1 discloses a structure that gradually decreases the moment of inertia of the cross section by changing the height of the trailing arm in the longitudinal direction from the mounting portion of the trailing arm that is a suspension system of the automobile. In order to improve the impact resistance of the center pillar, the structure changed so that the section modulus increases from the roof side to the floor side of the center pillar is disclosed in Patent Document 3, and the rigidity and energy absorption characteristics of the center pillar of an automobile are also disclosed. Patent Document 4 discloses a structure that increases the section modulus of the upper part of the center pillar and decreases the section coefficient of the lower part for the purpose of improving Respectively have been disclosed. Further, Patent Document 5 discloses a bracket including a main plate and a pair of side plates joined to both ends of the main plate in an H shape for the purpose of improving the rigidity of the subframe of the automobile.

JP-A-6-31669 JP 2001-191775 A JP-A-10-175656 JP 2001-163257 A JP-A-11-105734

  Among the disclosed technologies, Patent Document 1 is a technology that can efficiently share the torsional load by making the point of application of the pipe having a circular cross section rhombus, and improve the torsional rigidity without increasing the cross-sectional area. There is a problem that it cannot be applied to members other than circular cross sections.

  Further, Patent Document 2 is a technique for gradually reducing the secondary moment of section by gradually changing the height of the trailing arm, which is an automobile member, from the mounting portion, but there is a problem that the deflection of the member cannot be greatly reduced.

  Patent Document 3 describes an impact-resistant structure in which the center pillar, which is also an automobile member, has a cross-sectional modulus that increases from the roof side to the floor side. There is a problem that it is continuously changing and the bending of the member cannot be greatly reduced.

  Furthermore, Patent Document 4 describes a structure in which the section modulus of the center pillar is large at the top and small at the bottom, but there is a problem that the bending of the member cannot be greatly reduced.

  In addition, Patent Document 5 describes a technique for increasing the rigidity of the side frame by a bracket composed of a main plate and a pair of side plates joined to both ends of the main plate in an H shape, but greatly reduces the bending of the member. There is a problem that you can not.

  An object of this invention is to provide the structure which reduces the bending of a member with respect to the load input from a bracket.

In order to solve the above-described problems, the present invention provides (1) a structure configured in a frame shape by combining two pairs of members, and the inner surface and the outer surface of the pair of members of the two pairs of members. There are on the curve having a radius of curvature toward the outer side from the center of the structure, the inner curvature side radius much larger than the radius of curvature of the outer surface, the radius of curvature of the outer surface of the structure R1 (mm), And the radius of curvature R2 (mm) of the inner surface is
R1 / R2 ≦ 0.95
A structure characterized by satisfying the above is provided.

According to the present invention, there is further provided (2) the structure according to (1) above, wherein R1 / R2 ≧ 0.75 and R2 ≧ 1000 (mm) .

  According to the present invention, the bending of a member can be reduced without increasing the weight of the structure, and its industrial significance is great.

It is a perspective view which shows a mode that the member 2 of the structure 1 of this invention bends. It is a perspective view which shows a mode that the member 2 of another structure 1 of this invention bends. It is a perspective view which shows a mode that the member 2 of the conventional structure 1 bends. (A) It is a figure which shows the shape of the cross section of the member 2 of FIG. (B) It is a figure which shows another shape of the cross section of the member 2 of FIG. (C) It is a figure which shows another shape of the cross section of the member 2 of FIG. It is a figure which shows the test condition and the bending of a structure in the Example of this invention.

  Hereinafter, the present invention will be described in detail with reference to the drawings. In the present specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  First, as shown in FIG. 3, the inventors of the present invention have a structure 1 in which two pairs of members are combined at a substantially right angle to form a frame shape. When the load P is input, that is, when the load is input in the in-plane direction of the structure 1, the bending y of the member 2 of the structure 1 was examined in detail. Here, the load P is input from, for example, a bracket provided on the member 2.

  As a result, since the structure 1 is largely deformed near the center, the deflection y when the load P is input toward the inside of the structure 1 greatly depends on the cross-sectional secondary moment in the center 4 of the member 2. As a result, various shapes for reducing the deflection y near the center 4 were studied. As a result, as shown in FIG. 1, the inner side surface 5 and the outer side surface 6 of the pair of members 2 constituting the structure 1 have a radius of curvature from the center of the structure 1 to the outside, and are within the surface of the structure 1. It has been found that it is very effective in reducing the deflection y of the member 2 that it is on a curve that fits and that the curvature radius R2 of the inner surface 5 is larger than the curvature radius R1 of the outer surface 6. That is, by making the curvature radius R2 of the inner surface 5 larger than the curvature radius R1 of the outer surface 6, the height h of the portion near the center 4 of the member 2 is made larger than the height of the end portion of the member 2. Since the second moment of section of the portion can be increased, the thickness of the section can be reduced and the weight can be reduced, and the inner surface 5 and the outer surface 6 can be moved from the center of the structure 1. It has been found that since the bending moment M at the corner portion 7 can be reduced by being on the curve having the radius of curvature toward the outside, the cross section of the other pair of members 3 to which the load P does not act can be reduced.

  When the inner side surfaces 5 of the pair of members 2 constituting the structure 1 are linear or on a curve having a radius of curvature from the center of the structure 1 to the inside, the cross-sectional secondary moment around the center 4 is large. However, since the cross-sectional area of the corner 7 is extremely smaller than the cross-sectional area in the vicinity of the center 4, the deformation of the corner 7 becomes large and the deflection y of the member 2 cannot be reduced. When the curvature radius R2 of the inner side surface 5 of the member 2 is the same as the curvature radius R1 of the outer side surface 6, the deflection of the member 2 is larger than that of the linear structure, and the curvature radius of the inner side surface 5 of the member 2 is further increased. When R2 is smaller than the radius of curvature R1 of the outer surface 6, the cross-sectional area in the vicinity of the center 4 is smaller than the corner portion 7, so that the deflection y of the member 2 cannot be reduced. Moreover, it discovered that the joining state of a pair of member 2 and the other pair of member 3 which comprises the structure 1 has the same effect not only in the form of FIG. 1 but in the form of FIG. That is, the same effect is obtained when the member 2 is joined to the end faces of both ends of the member 3 as shown in FIG. 1 and when the member 2 is joined to the inner side surfaces of both ends of the member 3 as shown in FIG. .

  As described above, the inner surface 5 and the outer surface 6 of the pair of members 2 constituting the structure 1 are on a curve having a radius of curvature from the center of the structure 1 toward the outside, and the curvature radius of the inner surface 5 is further increased. It has been clarified that in the structure in which R2 is larger than the radius of curvature R1 of the outer surface 6, the deflection y of the member 2 is greatly reduced.

  Next, the inventors examined in detail the relationship between the curvature radius R1 of the outer surface 6 and the curvature radius R2 of the inner surface in order to further reduce the deflection y of the member 2 of the structure 1.

As a result, when the radius of curvature of the outer surface 6 of the structure 1 is R1 (mm) and the radius of curvature of the inner surface 5 is R2 (mm),
R1 / R2 ≦ 0.95 (1)
The structure 1 satisfying the above has found that the deflection y of the member 2 can be greatly reduced.

  When R1 / R2 is greater than 0.95, the curvature radii of R1 and R2 are very close to each other, so that the cross-sectional area of the center 4 is almost the same as that of the corner 7 and greatly reduces the deflection y of the member 2. It is not possible. When R1 / R2 is reduced, the height h near the center 4 is increased and the second moment of section is increased to reduce the deflection y. Therefore, the lower limit is not particularly limited, but R1 / R2 is extremely limited. Since the height h of the center vicinity 4 becomes too large when it becomes smaller, the overall size of the structure 1 becomes too large, and a problem of interference with other members occurs in the structure in which the structure 1 is incorporated. It is desirable that /R2≧0.75 and R2 ≧ 1000 (mm). In the case of R1 / R2 <0.75 or R2 <1000 (mm), the height h of the member 2 becomes too large, and the increase in the area of the upper surface of the member 2 may exceed 50%. There is a problem that interferes with.

  Also, the upper limit of R2 is not particularly limited. However, when R2 is larger than 5000 mm, R1 is similarly increased, so that the cross-sectional area near the center 4 is very close to the corner 7 and the member 2 is linear. Therefore, the reduction of the deflection y is not so great.

  As described above, in the structure in which the curvature radius R1 (mm) of the outer surface 6 and the curvature radius R2 (mm) of the inner surface 5 of the structure 1 satisfy Expression (1), the bending y of the member is greatly reduced. It became clear that we could do it.

  The structure 1 of the present invention does not depend on the type of material, and can be applied to any material such as steel, aluminum and its alloys, titanium and its alloys, magnesium and its alloys, and resins. The same effect can be obtained even if the pipe material is processed or cast / forged. Further, since the present invention is a structure in which the shape of the member is devised to reduce the deflection y, it is effective for all materials regardless of the chemical composition, mechanical properties, etc. of the material.

  Moreover, the cross-sectional shape of the member 2 of the structure 1 is not particularly limited, and may be a solid cross section or a hollow cross section, a round shape, an oval shape, a triangular shape, a quadrangular shape, or a partial combination thereof. It goes without saying that even if the cross-sectional shape is different, the bending y can be reduced even in various shapes such as those shown in FIGS. However, from the viewpoint of emphasizing weight reduction of the structure, it is preferable that the hollow cross section is used. Even if the cross section is either an open cross section or a closed cross section, it is also bent with respect to a member in which a reinforcing member is included. y can be reduced.

  The member 2 of the structure 1 can be manufactured by processing a pipe material by a method such as pressing or hydroforming, or by a joining method such as welding of a member divided into two or more.

  In addition, the present invention can reduce the deflection y of the structural member even when the thickness or cross-sectional shape of the structural member changes along the length of the structural member.

  The structure 1 of the present invention can be applied to, for example, an engine cradle at the front of an automobile, a front subframe around the undercarriage, and a rear subframe.

  As mentioned above, although preferred embodiment of this invention was described, this invention is not limited to this example. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

  Based on the above-described invention, the inner surface 5 and the outer surface 6 of the pair of members 2 are on a curve having a radius of curvature from the center of the structure to the outside, and the curvature radius R2 of the inner surface 5 is the radius of the outer surface 6. A structure 1 larger than the radius of curvature R1 was produced. A load P of 1000 kg shown in FIG. 5 was applied to the member 2 in the in-plane direction of the structure 1 toward the inside of the structure 1, and the deflection y of the member 2 was measured. At this time, the influence of the rotational displacement of the corner 7 of the member 2 was subtracted, and only the deflection y of the member 2 due to deformation was obtained. As a comparative example, as shown in FIG. 3, a structure including the member 2 having no curvature on the inner side surface 5 and the outer side surface 6, and a structure in which the curvature radius R <b> 1 of the inner side surface 5 is the same as or smaller than the curvature radius R <b> 2 of the outer side surface 6. The body 1 was also manufactured and a loading test was performed in the same manner. The members 2 and 3 of the structure 1 were all made of steel with a plate thickness of 2.3 mm and a tensile strength of 780 MPa.

  The results are shown in Tables 1 to 4. In addition, the “bending reduction rate” in the table is a reduction rate with respect to the bending y of the structure 1 made of a member having no curvature on the inner side surface 5 and the outer side surface 6. Similarly, the “weight reduction rate” is the inner side surface. 5 and the weight reduction rate with respect to the weight of the structure 1 composed of the member 2 having no curvature on the outer surface 6. Further, the “area increase rate” indicates an increase rate with respect to the area of the upper surface of the member 2 of the structure 1 composed of the member 2 having no curvature on the inner surface and the outer surface. Moreover, the numerical value which underlined in the table | surface shows what does not satisfy | fill either conditions among this invention.

  No. in Table 1 Reference numerals 2 to 14 denote structures when the inner surface has a radius of curvature R2 of 900 mm, and the inner surface has a radius of curvature R2 larger than the radius of curvature of the outer surface, that is, R1 / R2 is smaller than 1. This is an example of the invention (invention according to claim 1 of the present application), and is a comparative example No. of a structure made up of members having no curvature on the inner and outer surfaces. The deflection reduction rate was 3% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In addition, comparative example No. of the structure in which the curvature radius R2 of the inner surface is the same as the curvature radius R1 of the outer surface. 15 and Comparative Example No. 1 of a structure in which the curvature radius R2 of the inner surface is smaller than the curvature radius R1 of the outer surface. It was also found that No. 16 does not reduce the deflection y under conditions where the weight is not increased. Furthermore, no. Nos. 2 to 13 are examples of the present invention (invention according to claim 2 of the present application) in which R1 / R2 is 0.95 or less, and a comparative example No. of a structure composed of members having no curvature on the inner surface and the outer surface. . The deflection reduction rate was 5% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases.

Similarly, No. 1 in Table 1 is used. Reference numerals 17 to 30 denote structures when the inner surface has a radius of curvature R2 of 980 mm, and the inner surface has a radius of curvature R2 larger than the radius of curvature of the outer surface, that is, R1 / R2 is smaller than 1. This is an example of the invention (invention according to claim 1 of the present application), and is a comparative example No. of a structure formed of members having no curvature on the inner side surface and the outer side surface. The deflection reduction rate was 3% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In addition, comparative example No. of the structure in which the curvature radius R2 of the inner surface is the same as the curvature radius R1 of the outer surface. 31. Further, Comparative Example No. 31 of the structure in which the curvature radius R2 of the inner surface is smaller than the curvature radius R1 of the outer surface. It has also been found that No. 32 does not reduce the deflection y under conditions where the weight is not increased. Furthermore, no. 17 to 29 are examples of the present invention (invention according to claim 2 of the present application) in which R1 / R2 is 0.95 or less, and a comparative example No. of a structure formed of members having no curvature on the inner side surface and the outer side surface . The deflection reduction rate was 5% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases.
As described above, it has been found that the structure of the present invention is effective in reducing the deflection y of the structural member.

  No. in Table 2 Reference numerals 33 to 47 denote structures when the radius of curvature R2 of the inner surface is 1010 mm, and the radius of curvature R2 of the inner surface is larger than the radius of curvature R1 of the outer surface, that is, R1 / R2 is smaller than 1. This is an example of the invention (invention according to claim 1 of the present application), and is a comparative example No. of a structure made up of members having no curvature on the inner and outer surfaces. The deflection reduction rate was 3% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In addition, comparative example No. of the structure in which the curvature radius R2 of the inner surface is the same as the curvature radius R1 of the outer surface. 48, and comparative example No. of the structure in which the curvature radius R2 of the inner surface is smaller than the curvature radius R1 of the outer surface. It was also found that No. 49 does not reduce the deflection y under conditions where the weight is not increased. Furthermore, no. 33 to 46 are examples of the present invention (invention according to claim 2 of the present application) in which R1 / R2 is 0.95 or less, and a comparative example No. of a structure formed of members having no curvature on the inner surface and the outer surface. . The deflection reduction rate was 5% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In particular, No. 1 in which R1 / R2 is in the range of 0.75 to 0.95. In 38 to 46, the area increase rate of the member is 50% or less, and the deflection reduction rate is 5% or more without greatly increasing the member area.

Similarly, in Table 2, No. Reference numerals 50 to 66 denote structures when the inner surface has a radius of curvature R2 of 2000 mm, and the inner surface has a radius of curvature R2 larger than the radius of curvature of the outer surface, that is, R1 / R2 is smaller than 1. This is an example of the invention (invention according to claim 1 of the present application), and is a comparative example No. of a structure formed of members having no curvature on the inner side surface and the outer side surface. The deflection reduction rate was 3% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In addition, comparative example No. of the structure in which the curvature radius R2 of the inner surface is the same as the curvature radius R1 of the outer surface. 67, and comparative example No. of the structure in which the curvature radius R2 of the inner surface is smaller than the curvature radius R1 of the outer surface. It was also found that No. 68 does not reduce deflection y under conditions that do not increase weight. Furthermore, no. 50 to 65 are examples of the present invention (invention according to claim 2 of the present application) in which R1 / R2 is 0.95 or less, and a comparative example No. of a structure formed of members having no curvature on the inner side surface and the outer side surface . The deflection reduction rate was 5% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In particular, No. 1 in which R1 / R2 is in the range of 0.75 to 0.95. In 56 to 65, the area increase rate of the member is as small as 20% or less, and the deflection reduction rate is 5% or more without greatly increasing the member area.
As described above, it has been found that the structure of the present invention is effective in reducing the deflection y of the structural member.

  No. in Table 3 69 to 85 are structures when the inner surface has a radius of curvature R2 of 3000 mm, and the inner surface has a radius of curvature R2 larger than the radius of curvature of the outer surface R1, that is, R1 / R2 is smaller than 1. This is an example of the invention (invention according to claim 1 of the present application), and is a comparative example No. of a structure made up of members having no curvature on the inner and outer surfaces. The deflection reduction rate was 3% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In addition, comparative example No. of the structure in which the curvature radius R2 of the inner surface is the same as the curvature radius R1 of the outer surface. 86, and Comparative Example No. No. 86 of a structure in which the curvature radius R2 of the inner surface is smaller than the curvature radius R1 of the outer surface. It was also found that No. 87 does not reduce deflection y under conditions that do not increase weight. Furthermore, no. 69 to 84 are embodiments of claim 2 (invention according to claim 2) of the present invention in which R1 / R2 is 0.95 or less, and a structure formed of members having no curvature on the inner side surface and the outer side surface Comparative Example No. The deflection reduction rate was 5% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In particular, No. 1 in which R1 / R2 is in the range of 0.75 to 0.95. In 75 to 84, the area increase rate of the member is as small as 10% or less, and the deflection reduction rate is 5% or more without greatly increasing the member area.

Similarly, in Table 3, No. Reference numerals 88 to 102 denote structures in which the inner surface has a radius of curvature R2 of 5000 mm, and the inner surface has a radius of curvature R2 that is larger than the radius of curvature of the outer surface, that is, R1 / R2 is smaller than 1. This is an example of the invention (invention according to claim 1 of the present application), and is a comparative example No. of a structure formed of members having no curvature on the inner side surface and the outer side surface. The deflection reduction rate was 3% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In addition, comparative example No. of the structure in which the curvature radius R2 of the inner surface is the same as the curvature radius R1 of the outer surface. 103, and comparative example No. of the structure in which the curvature radius R2 of the inner surface is smaller than the curvature radius R1 of the outer surface. It has also been found that 104 does not reduce the deflection y under conditions that do not increase weight. Furthermore, no. Nos. 88 to 101 are examples of the present invention (invention according to claim 2 of the present application) in which R1 / R2 is 0.95 or less, and a comparative example No. of a structure formed of members having no curvature on the inner side surface and the outer side surface . The deflection reduction rate was 5% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In particular, No. 1 in which R1 / R2 is in the range of 0.75 to 0.95. In 94 to 101, the area increase rate of the member is as small as 6% or less, and the deflection reduction rate is 5% or more without greatly increasing the member area.
As described above, it has been found that the structure of the present invention is effective in reducing the deflection y of the structural member.

  No. in Table 4 105 to 118 are structures in which the inner surface has a radius of curvature R2 of 7000 mm, and the inner surface has a radius of curvature R2 larger than the radius of curvature of the outer surface, that is, R1 / R2 is smaller than 1. This is an example of the invention (invention according to claim 1 of the present application), and Comparative Example No. The deflection reduction rate was 3% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In addition, comparative example No. of the structure in which the curvature radius R2 of the inner surface is the same as the curvature radius R1 of the outer surface. 119, and Comparative Example No. 1 of a structure in which the curvature radius R2 of the inner surface is smaller than the curvature radius R1 of the outer surface. It has also been found that 120 does not reduce deflection y under conditions that do not increase weight. Furthermore, no. Nos. 105 to 117 are examples of the present invention (invention according to claim 2 of the present application) in which R1 / R2 is 0.95 or less, and a comparative example No. of a structure including members having no curvature on the inner side surface and the outer side surface . The deflection reduction rate was 5% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In particular, No. 1 in which R1 / R2 is in the range of 0.75 to 0.95. In 110 to 117, the area increase rate of the member is as small as 4% or less, and the deflection reduction rate is 5% or more without greatly increasing the member area.

Similarly, in No. 4 of Table 4, Reference numerals 121 to 134 denote structures when the inner surface has a radius of curvature R2 of 10,000 mm, and the inner surface has a radius of curvature R2 larger than the radius of curvature of the outer surface, that is, R1 / R2 is smaller than 1. This is an example of the invention (invention according to claim 1 of the present application), and is a comparative example No. of a structure formed of members having no curvature on the inner side surface and the outer side surface. The deflection reduction rate was 3% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In addition, comparative example No. of the structure in which the curvature radius R2 of the inner surface is the same as the curvature radius R1 of the outer surface. 135, and comparative example No. of a structure in which the curvature radius R2 of the inner surface is smaller than the curvature radius R1 of the outer surface. It was also found that 136 does not reduce flexure y under conditions that do not increase weight. Furthermore, no. 121 to 133 are examples of the present invention (invention according to claim 2 of the present application) in which R1 / R2 is 0.95 or less, and a comparative example No. of a structure including members having no curvature on the inner side surface and the outer side surface . The deflection reduction rate was 5% or more without increasing the weight as compared with 1, and it was found that the deflection y was greatly reduced in all cases. In particular, No. 1 in which R1 / R2 is in the range of 0.75 to 0.95. In 126 to 133, the area increase rate of the member is as small as 2.5% or less, and the deflection reduction rate is 5% or more without greatly increasing the member area.
As described above, it has been found that the structure of the present invention is effective in reducing the deflection y of the structural member.

  The present invention can be applied to a structure that reduces deflection without increasing the weight.

DESCRIPTION OF SYMBOLS 1 Structure 2 Member 3 Member where load does not act 4 Center vicinity 5 Inner side surface of member 2 Outer side surface of member 2 Corner | angular part P Load y Deflection

Claims (2)

A structure that is configured in a frame shape by combining two pairs of members, the curved surface having an inner surface and an outer surface of the pair of members having a radius of curvature directed outward from the center of the structure. to Yes, the radius of curvature of the inner surface is much larger than the radius of curvature of the outer surface,
The curvature radius R1 (mm) of the outer surface of the structure and the curvature radius R2 (mm) of the inner surface are:
R1 / R2 ≦ 0.95
A structure characterized by satisfying The structure according to claim 1, wherein R1 / R2 ≧ 0.75 and R2 ≧ 1000 (mm).

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