JP5357786B2 - Aluminum alloy extrusions for structural members - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aluminum alloy extruded shape that is, even when a bending load and a torsional moment with the fulcrum at one end and an application point of force at the other end are applied while in use as a structural member supported or jointed at both ends, less likely to be subjected to a break or a buckling distortion at the one end side being the fulcrum, so as to exhibit a high distortion strength. <P>SOLUTION: The aluminum alloy extruded shape 1, onto which the bending load and the torsional moment are loaded while in use, is made of a high-strength aluminum alloy. and includes a closed cross-sectional portion 8, and a flat protruded flange portion 6 projected from a wall that constitutes this closed cross-sectional portion 8 in the direction toward the outside of bending when the bending moment is applied. This protruded flange portion 6 is protruded from any portion of the wall near the outside and formed into a shape with a width of this protruded flange portion 6 varying from a narrow width to a wide width, so as to enhance the distortion strength. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an aluminum alloy extruded shape for a structural member. Hereinafter, the aluminum alloy extruded profile is also simply referred to as an extruded profile.

  As is well known, relatively high-strength steel and aluminum alloy materials are used for structural members such as frames, members, reinforcements, etc. of automobiles and various vehicles, or various structural members (parts) in vehicles. It is used.

  In particular, in the case of automobiles and various vehicles, there is a problem of a vehicle body collision due to an accident, and the structural member to which a strong impact load is applied at the time of the collision is not only increased in strength but also broken or broken against the impact load. A high deformation strength that does not cause buckling deformation is required.

  For such structural member applications, processed products and molded products of high-tensile steel sheets are conventionally used. However, in recent years, it is also desired to reduce the weight of the structural member itself from the viewpoint of reducing the weight of the vehicle body. For this reason, the application of an aluminum alloy material has been studied or put into practical use in place of these high-tensile steel sheets for structural member applications that require high deformation strength.

  In particular, the extruded shape of an aluminum alloy does not require difficult forming as in the case of using an aluminum alloy plate, and the cross-sectional shape is uniform in the longitudinal direction (extrusion direction). The present invention can be advantageously applied to a structural member having a cross-sectional shape that makes the best use of. For example, if the aluminum alloy extruded profile has a closed cross-sectional structure having a hollow structure, it can be directly replaced by a steel plate structural member having the same hollow structure such as a HAT type by forming or welding. Further, if the aluminum alloy extruded shape has a closed cross-sectional structure having a hollow structure, the deformation strength can be increased as compared with the aluminum alloy extruded shape having a solid open cross-sectional structure.

  For this reason, an extruded profile having such a closed cross-sectional structure is used as a vehicle body structural member, for example, an automobile cross member (see Patent Document 1), an impact beam for an automobile side door (see Patent Document 2), an automobile, and the like. In recent years, many roof reinforcing materials (see Patent Document 3) have been studied or put into practical use.

  These structural members of the extruded vehicle body have a closed cross-sectional structure that is a hollow structure with a rectangular cross section, and in common, are extended laterally from the closed cross-sectional structure in order to increase the deformation strength. It has a protruding flange. Such a combination of a closed cross-sectional structure and a protruding flange portion is well known as a structural member of another vehicle body such as an automobile bumper reinforcement made of an extruded profile.

JP 2006-240543 A JP 2008-285019 A JP 2009-35244 A

  However, a common feature of the structural members of the vehicle body made of these aluminum alloy extruded shapes is that the cross-sectional shape of the structural members is uniform in the longitudinal direction (in the extrusion direction) because it is necessarily an extruded material. Such a structural member of a vehicle body is highly deformed when a large impact load is applied in the longitudinal direction or the width direction of the extruded profile having the closed cross-section structure during use as a structural member in which both ends are supported or joined. Indicates strength.

  However, in the case of a long structural member that is supported or joined at both ends, depending on how an impact load is applied to the vehicle body or the structure itself in which the structural member is incorporated, such as a vehicle body collision of the automobile, There is a case where a bending load is applied to one end side in the longitudinal direction of an aluminum alloy extruded profile which is a long structural member.

  In this way, when a large impact load is applied with one end as a fulcrum and the other end as an action point, the long aluminum alloy extruded shape with a uniform cross-sectional shape in the longitudinal direction (in the extrusion direction) There is a problem in that the deformation strength on one end side serving as a fulcrum tends to be insufficient, and breakage or buckling deformation tends to occur at this portion. On the other hand, when the cross-sectional shape is such that sufficient deformation strength can be ensured on the fulcrum side, the cross-section on the side of the action point where the stress is small becomes excessively designed, resulting in an increase in weight.

  Furthermore, a torsional moment is generated in the longitudinal direction of the shape depending on the position and direction of the bending load. For example, a torsional moment is generated when a load is transmitted through another part attached to the point of application, or when a load is applied to a part of the cross section constituting a structural part. In the case of a component that does not have sufficient torsional rigidity, the deformation load is reduced and the deformation amount is increased due to the torsional moment. That is, it is also important to ensure sufficient torsional rigidity that can cope with such a torsional moment.

  Therefore, the object of the present invention is to use the above-mentioned one end as a fulcrum and the other end as a working point during use as a structural member that is supported or joined at both ends. The object is to provide an aluminum alloy extruded shape which is not easily broken or buckled and has a high deformation strength at one end serving as a fulcrum.

  In order to achieve the above object, the gist of the extruded aluminum alloy for structural members having high deformation strength according to the present invention is aluminum in which bending load and torsional moment are applied to one end in the longitudinal direction during use as a structural member. An elongated extruded section having a 0.2% proof stress of 300 MPa or more and the same cross-sectional shape over the entire length, and one wall constituting the closed section A flat projecting flange projecting in the direction of bending outward when the bending load is applied over the entire length of the closed section, and the width of the projecting flange is one end serving as the action point of the closed section. From the side to the other end side as the fulcrum, it has a shape that continuously changes from narrow to wide.

  Here, it is preferable that one surface of the protruding flange portion of the aluminum alloy extruded profile is flush with the outer wall surface of one wall constituting the closed cross-sectional portion. Moreover, it is preferable that the closed cross-section part of the said aluminum alloy extruded shape material had the rectangular cross-sectional shape formed with four walls. Further, the closed section of the aluminum alloy extruded profile is configured, and at least a part of the wall located inside the bend when the bending load is applied is thicker than the thickness of the other walls configuring the closed section. It is preferably meat. Moreover, it is preferable that at least a part of the end portion of the protruding flange portion of the aluminum alloy extruded shape member is bent in one direction over the longitudinal direction.

  The aluminum alloy extruded profile is obtained by bisecting the material aluminum alloy extruded profile, and the material aluminum alloy extruded profile has two cross-sectional shapes that are the same over the entire length. It consists of a parallel long closed cross-section portion and a flat flange portion that is interposed between these closed cross-section portions and connects the closed cross-section portions to each other, and this flange is cut obliquely over the longitudinal direction. A protruding flange is formed, and it is preferable that the aluminum alloy extruded profile is bisected so that the shapes thereof are point-symmetric when viewed in plan. Moreover, it is preferable that the thickness of the thinnest wall is the range of 1.8 mm-3 mm among the closed cross-section parts of the said aluminum alloy extrusion shape material.

  Here, the above-mentioned long aluminum alloy extruded shape is at first glance (easily) identified with respect to the length in the width direction (width, length in the cross-sectional direction). It is an aluminum alloy extruded profile having a longitudinal length that is sufficient to be possible.

  When a bending load and a torsional moment are applied to one end in the longitudinal direction as described above, as shown in FIG. 1, in many cases, one end in the longitudinal direction of the aluminum alloy extruded profile 1 as a structural member is used as a fulcrum, and the other end is used as a fulcrum. Loaded as an action point. In this case, the bending moment M1 generated by the bending load P1 applied to the upper end 1a of the aluminum alloy extruded profile 1 shown in FIG. 1 becomes maximum at the lower end 1b. For this reason, in order to increase the deformation strength of the aluminum alloy extruded shape 1 efficiently, it is necessary to design the height in the load direction of the cross section so that the bending strength becomes higher at the lower end 1b.

  Corresponding to the bending load applied to one end in the longitudinal direction of the extruded profile (one end of the extruded profile is the fulcrum and the other is the working point), the direction that becomes the outside of the bending when the bending load is applied is pulled It was found that only the compressive stress is applied to the portion where only the load becomes inside the bend. Moreover, in the case of general structural parts, since the influence of the torsional moment is smaller than the bending moment caused by the bending load, it was also found that there is no significant difference in this tendency even when the torsional moment is applied.

  In other words, depending on the applied bending load, there are portions in the cross section that become the tensile load side and the compressive stress side, and the optimum cross-sectional shape for obtaining a predetermined deformation strength is different. ing.

  For this reason, in the present invention, in the structural member to which a bending load and a torsional moment are applied in the above-described state, particularly on the side to which only the tensile load is applied, the closed cross-section portion is provided for weight reduction and workability described later. 8 is not intentionally configured (arranged), but only the protruding flange portion 6 is arranged as in the extruded profile 1 of FIG.

  However, if the protruding flange portion 6 has the same width in the longitudinal direction of the structural member 1 (vertical direction in FIG. 1) and the sectional shape of the protruding flange portion 6 is uniform in the longitudinal direction, as described above. The deformation strength on the lower end 6b side of the projecting flange portion 6 is insufficient, or the working point side is overdesigned, resulting in an increase in weight.

  For this reason, in the present invention, the width of the projecting flange portion 6 is changed from a narrow width to a wide width from the one end 1a side serving as the action point of the closed cross section 8 toward the other end 1b side serving as the fulcrum. Change continuously. That is, the width of the projecting flange portion 6 is increased toward the lower end 6b side as compared with the upper end 6a side, and the sectional width in the load direction is increased toward the lower end 6b side to increase the bending deformation strength. .

On the other hand, in the present invention, in the structural member to which a bending load and a torsional moment are applied in the above-described state, a closed cross-section portion having a hollow structure is formed particularly on the side to which the compressive stress caused by the bending load is applied ( Deploy. By arranging a closed cross-section portion instead of an open cross-section structure inside the bending side on the fulcrum side to which the highest compressive stress is applied, the buckling strength can be improved and the deformation strength can be improved.
The closed cross-sectional structure is characterized in that it is provided along the longitudinal direction of the frame (over the entire surface in the longitudinal direction). Since the torsional moment is applied throughout the longitudinal direction of the component, the deformation strength can be remarkably improved by providing a closed cross-sectional structure with high torsional rigidity over the entire longitudinal direction.

  Accordingly, in the present invention, even when the bending load and the torsional moment are applied to the structural member in combination, it is possible to obtain a high deformation strength that does not break or buckle. And this effect can be achieved in the range which does not inhibit the weight reduction effect by an aluminum alloy extrusion shape material.

  However, since the extruded shape of the aluminum alloy is necessarily an extruded material, the cross-sectional shape is uniform in the longitudinal direction (in the extrusion direction), and it is difficult to vary the cross section in the longitudinal direction (in the extrusion direction). For this reason, although the said closed cross-section part of this invention may have uniform cross-sectional shape in a longitudinal direction (extrusion direction), since it is integrally provided in this, it is assumed that it is extruded integrally. As described above, it is technically very difficult to extrude the flange portion so that the cross-sectional width changes along the longitudinal direction.

  The difficulty in manufacturing a variable cross-sectional width by such extrusion is present in an extruded profile having a protruding flange portion having a shape that continuously changes from narrow to wide as in the present invention. When an extruded profile having a uniform cross-sectional shape in the longitudinal direction (extrusion direction) (the projecting flange portion having a uniform width in the longitudinal direction and the closed cross-section portion are integrated) is used as a material, This is because the material yield becomes very poor. That is, when the projecting flange portion of the extruded material is cut obliquely to change from a narrow width to a wide width, large triangular chips are generated when cutting obliquely, resulting in a very poor material yield.

  Therefore, the extruded section having a variable cross-sectional width structure as in the present invention is not intended to be manufactured by those skilled in the art unless the material yield is improved or a method of making the material yield is not devised.

  For example, as means for changing the cross section in the longitudinal direction of an aluminum alloy extruded profile, known processes include post-processing such as pressing and hydroforming. However, these methods have a large problem that the processing cost becomes high and the elongation of the aluminum alloy material is low, so that breakage easily occurs and the product shape is limited. In particular, when a high-strength 7000 series alloy is used, there is a concern that stress corrosion cracking due to high residual stress after processing may also be a problem. The difficulty in manufacturing a variable cross-sectional width by such extrusion is also a reason (inhibition factor) that it is difficult to assume a member having a variable cross-sectional width as in the present invention when an extruded profile is used.

  On the other hand, in the present invention, the method of producing such an extruded profile having a variable cross-sectional width is also devised, and the aluminum alloy extruded profile is divided into two parts so that it can be easily obtained.

  That is, as will be described later, an aluminum alloy extruded profile is closed by inserting two parallel long closed cross-sections having the same cross-sectional shape over the entire length, and between these closed cross-sections. Extruded as a uniform cross-sectional shape in the longitudinal direction (in the extruding direction) consisting of flat flange portions that connect the cross-sectional portions to each other. And in this raw material aluminum alloy extruded shape, when the protruding flange portion is formed by obliquely cutting the protruding flange portion along the longitudinal direction, and the raw material aluminum alloy extruded shape is viewed in plan view It can be obtained by bisecting so that their shapes are point-symmetric. Therefore, an extruded profile having a variable cross-sectional width can be easily obtained without using the above-described cutting process with a very low material yield.

  Further, unlike the case of cutting the closed cross section, the cutting process of the open cross section can be easily performed using shear cutting or the like. And by arranging the obtained protruding flange part at the part where the tensile load is applied when bending load is applied as described above, only the tensile load can be avoided. Thus, an extruded profile that is lightweight, has high deformation strength, and can be produced at low cost can be obtained.

It is a perspective view which shows one aspect | mode of this invention aluminum alloy extrusion shape material. It is a side view of FIG. It is a perspective view which shows the example of application to the structural member of the extrusion shape member of FIG. 1 which concerns on this invention. It is a perspective view which shows how to make the extrusion shape material of FIG. It is a perspective view which shows another aspect of this invention aluminum alloy extrusion shape member. It is sectional drawing which shows another aspect of this invention extrusion shape member. It is sectional drawing which shows another aspect of this invention extrusion shape member. It is sectional drawing which shows another aspect of this invention extrusion shape member. It is sectional drawing which shows another aspect of this invention extrusion shape member. It is sectional drawing which shows another aspect of this invention extrusion shape member. It is sectional drawing which shows another aspect of this invention extrusion shape member.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a case in which an aluminum alloy extruded profile according to the present invention is used by being erected in the vertical direction of a vehicle body, taking as an example a stay of an instrument panel reinforcing material used in an automobile body. FIG. 2 is a side view of FIG.

  Here, as shown in FIG. 3, the instrument panel reinforcing material is installed such that its axial direction (longitudinal direction) extends in the vehicle body width direction (from the lower left direction to the upper right direction in FIG. 3). In the case of this installation, both end portions 10a (driver's seat side) and 10b (passenger seat side) of the instrument panel reinforcement member 10 in the longitudinal direction (axial direction) are not shown through a body frame (not shown) via brackets 11 and 11 as mounting brackets. Is attached. Although not shown, the brackets 11 and 11 are usually attached to the vehicle body frame via brackets on the vehicle body frame side.

  In FIG. 3, one stay (stay) made of the extruded aluminum alloy material 1 of the present invention is attached near the center of the instrument panel reinforcing member 10 in the downward direction of the vehicle body (downward in FIG. 3). (2 may be attached at intervals). This stay (aluminum alloy extruded profile) 1 is joined at its lower end 1b to a vehicle body floor, which is not shown, in the lower direction of the vehicle body, either mechanically or by welding, and the instrument panel reinforcement 10 is attached to the vehicle body floor. It plays the role of connecting, fixing and supporting.

  Incidentally, FIG. 1 shows such a stay 1 of FIG. 3 as viewed from the left side of FIG. 3, wherein the left side direction of FIG. 1 is the front side of the automobile, the right side direction of FIG. 1 indicates the passenger seat side, and the depth direction in FIG. 1 indicates the driver seat side.

  As shown in FIG. 1, an aluminum alloy extruded profile 1 (stay 1) according to the present invention is erected over a long closed cross-sectional portion 8 extending in the vertical direction of the figure and over the entire length of the closed cross-sectional portion 8. And a flat projecting flange portion 6. Here, the long closed cross section 8 is erected on the front side of the vehicle body (upper left side in FIG. 3 and left side in FIG. 1), and the flat protruding flange portion 6 is on the rear side of the vehicle body (lower right direction in FIG. 3). On the right side of FIG. The projecting flange portion 6 is a portion of the rear wall 5 on the rear side of the vehicle body (the lower right direction in FIG. 3 and the right side in FIG. 1) constituting the closed cross section 8 that is located on the outermost side in the vehicle body width direction ( 1 protrudes and extends from the front side of FIG. 1 (the position on the lower left side in FIG. 3) to the rear side of the vehicle body (the lower right side in FIG. 3 and the right side in FIG. 1). Therefore, the outer surface in the vehicle body width direction of the projecting flange portion 6 is flush with the outer wall surface of the web wall 3 that is the outer wall surface in the vehicle body width direction constituting the closed cross section 8.

  In this way, the protruding flange portion 6 is arranged further on the passenger seat side (lower left side in FIG. 3) of the rear wall 5 on the rear side of the vehicle body (lower right direction in FIG. 3, right side in FIG. 1) constituting the closed section 8. It is possible to project and extend from a position (position) shifted (biased) toward the direction side, the front side in FIG. 1 to the rear side of the vehicle body (on the lower right side in FIG. 3 and on the right side in FIG. 1). As described later, it is preferable.

  Further, the width of the projecting flange portion 6 has a shape that continuously changes from the narrow width to the wide width from the upper end portion 1a to the lower end portion 1b of the closed cross section 8. In other words, the lower end side 1b of the projecting flange portion 6 has a larger cross-sectional width than the upper end side 1a. That is, the protruding flange portion 6 has a shape in which the flange width continuously changes from the narrow end to the wide end from the one end 6a side to the other end 6b side. When this corresponds to FIG. 1, the flange width of the projecting flange portion 6 is the end portion 6 a of the projecting flange portion 6, or the upper end portion side of the closed section 8 or the upper end portion of the aluminum alloy extruded profile 1. A shape that continuously changes from the narrow side to the wide side from the side 1a toward the lower end side of the closed cross section 8 or the lower end side 1b of the aluminum alloy extruded profile 1 that is the end 6b. Have.

  Here, the change in the flange width of the projecting flange portion 6 may change linearly as shown in FIG. 1, but in the form of a polygonal line or step as shown in FIG. The shape may change, and each of them has a shape that continuously changes from narrow to wide.

  In FIG. 1, when the aluminum alloy extruded profile 1 is used as the structural member (stay, etc.), for example, when a collision load is applied from the rear of the automobile (right side in FIG. 1), the extruded profile described above is used. A bending load P1 indicated by an arrow is applied from the upper end side 1a in the longitudinal direction toward the lower end side 1b with the lower end side 1b as a fulcrum and the upper end side 1a as an action point. Further, when this load is applied via other parts, the torsional moment M2 in the circumferential direction having the radial direction in the width direction (left-right direction in FIG. 1) of the extruded profile 1 is also on the upper end side 1a. To join.

  The bending load P1 and the torsional moment M2 are also shown in the instrument panel reinforcing material 10 in FIG. As shown in FIG. 3, when a collision load P is applied to the stay (extrusion profile) 1 from the rear of the vehicle (the direction on the lower right side in FIG. 3), the upper end 1a in the longitudinal direction of the stay and the lower end A bending load P1 indicated by an arrow is applied toward the side 1b with the lower end side 1b as a fulcrum and the upper end side 1a as an action point. Further, a torsional moment M2 in the circumferential direction having the radial direction in the width direction of the stay 1 (left and right direction in FIG. 3) is also applied to the upper end side 1a.

  As described above, the moment acting on the stay (extruded profile) 1 includes the bending moment M1 generated corresponding to the bending load P1 directed to the front side of the vehicle body and the front side of the vehicle body in the cross section of the profile as shown by the arrows in FIG. It consists of a torsional moment M2 that twists the portion in the direction of the passenger seat. Here, the bending moment M1 applied corresponding to the bending load P1 is maximized at the lower end portion 1b, and the protruding flange portion 6 on the rear side of the vehicle body (the right side in FIG. 1) is bent outward, the vehicle body front side (FIG. 1) is on the inside of the bend.

  With respect to such a composite moment, the structure of the aluminum alloy extruded profile 1 is relatively lightweight and can obtain high deformation strength. The reason for this will be explained below. The points for achieving both weight reduction and deformation strength improvement of the extruded profile 1 in consideration of such a composite moment are the improvement in torsional rigidity and the vehicle body resulting from the bending moment. Prevention of buckling of the front side portion, and three points of higher deformation strength on the other end side (lower end side in FIG. 1) than one end side (upper end side in FIG. 1) of the aluminum alloy extruded profile 1 .

Closed section function:
As can be seen from FIG. 1, the aluminum alloy extruded profile 1 of the present invention has a closed cross section 8 on the side to which the compressive stress due to the bending moment is applied (the front side of the vehicle body on the left side of FIG. 1, the front side of the vehicle body on the upper left side in FIG. 3). Have Such a closed cross-section structure is provided with a uniform cross-sectional shape over the entire length in the longitudinal direction of the extruded profile 1, which is also a feature of the extruded material. There is an effect that the torsional rigidity of the extruded profile 1 can be remarkably improved. Further, by disposing the closed cross section 8 on the side to which the compressive stress is applied due to the bending load (the vehicle body front side on the left side in FIG. 1 and the vehicle body front side on the left upper direction side in FIG. 3), The buckling strength can be suppressed and the buckling strength can be improved.

  In order to efficiently obtain a high bending strength and a weight reduction effect when the bending load is applied, it is necessary to increase the cross-sectional area at a position far from the neutral axis of the aluminum alloy extruded profile 1 or the closed cross-section 8. It is valid. In this respect, it is desirable to provide a flange 4 having a wall surface parallel to the vehicle body width direction, similar to the flange 5, on the vehicle body front side (vehicle body front side on the left side in FIG. 1). And it is desirable to provide the webs 2 and 3 which have a wall surface orthogonal to this flange 4 and 5 and extended in the vehicle body front-back direction (left-right direction of FIG. 1). Therefore, the hollow cross-sectional shape of the closed cross-sectional portion 8 is preferably a rectangle as shown in FIG.

Function of protruding flange:
As described above, the aluminum alloy extruded profile 1 according to the present invention is a direction in which the outer side is bent when the bending moment is applied from one wall 5 constituting the closed section 8 to the entire length of the closed section 8 (see FIG. 1 has a flat plate-like protruding flange portion 6 projecting to the right side of the vehicle body rear side).

  Further, the flat plate-like protruding flange portion 6 is protruded from the flange wall 5 (rear surface wall 5) constituting the closed section 8 to the rear side of the vehicle body. In the case of FIG. 1, the depth direction in FIG. 1 is the vehicle body width direction, and protrudes from the outermost side in the vehicle body width direction of the flange wall 5 constituting the closed cross section 8.

  Even if the torsional moment M2 is added to the bending moment M1 resulting from the vehicle body collision load to the aluminum alloy extruded shape 1, only the tensile load is applied to the rear side of the extruded shape 1 (right side in FIG. 1). Join. Therefore, it is not necessary to dare to form the closed cross section 8 on the rear side of the vehicle body of the extruded profile 1. In the present invention, a flat plate-like shape is considered in consideration of weight reduction and workability of the extruded profile 1. The projecting flange portion 6 is used. And as above-mentioned, the width | variety of this protrusion flange part 6 is made wider so that the cross-sectional width may increase toward the downward direction of the extrusion shape member 1 by making the lower end side 1b wider than the upper end side 1a of the extrusion shape member. The increase in weight can be suppressed to a minimum, and the bending deformation strength can be increased.

  Since such a protruding flange portion 6 has a problem that it tends to buckle and deform with respect to compressive stress, as described above, it is necessary to arrange it on the rear side of the vehicle body to which only a tensile load is applied during a collision. For this reason, when the bending load P1 is not parallel to the projecting flange 6 but has a slight angle, the projecting position from the flange wall 5 is selected so that compressive stress does not act when the load is applied. Is desirable.

  For example, as shown in FIG. 2, when there is a slight angle in the vehicle width direction, such as the direction of the load P1 combined with the main load P1 ′ and the sub load P1 ″, the bending load in the vehicle width direction On the other hand, it is more desirable to arrange the protruding flange portion 6 at a portion where the protruding flange portion 6 is bent outward. More specifically, the projecting flange portion 6 has a width d in the lateral direction (perpendicular to the longitudinal direction, the vehicle body width direction) of the flange wall 5 erected (on the vehicle body rear side) shown in FIG. It is desirable to project the vehicle rearward from the position in the bending outer direction in the width direction of the cross section, at least from the center portion (d / 2 portion). That is, as described above, the projecting flange portion 6 is placed outwardly in the vehicle body width direction of the rear wall 5 on the rear side of the vehicle body (the lower right direction in FIG. 3 and the right side in FIG. 1) constituting the closed section 8. It is preferable to project and extend from the part (position on the near side in FIG. 1, position on the lower left direction in FIG. 3) to the rear side of the vehicle body (on the lower right side in FIG. 3, right side in FIG. 1). In the profile 1 shown in FIG. 1, the protruding flange portion 6 protrudes and extends from the outermost portion of the rear wall 5 in the vehicle width direction to the vehicle rear side as described above.

  Moreover, even if it is the structure of the same aluminum alloy extrusion shape material 1, in order to obtain higher bending strength and to achieve weight reduction, the cross-sectional area of the position far from the neutral axis of the extrusion shape material 1 should be enlarged. Is effective. In order to enhance this effect, as described above, the protruding flange portion 6 is located at the most bending outer side with respect to the subload applied in the vehicle width direction, that is, flush with the outer wall surface 3 in the vehicle body width direction of the flange wall 5. It is desirable to arrange.

  In FIG. 1, a line indicated by a one-dot chain line is a neutral axis of the aluminum alloy extruded profile 1. The mode of FIG. 1 shows a specific mode for enlarging the cross-sectional area at a position far from the neutral axis indicated by the alternate long and short dash line, and the protruding flange portion 6 of the extruded profile 1 has the closed cross-section portion 8. The rear wall 5 protrudes from the outermost side in the width direction to the rear side of the vehicle body. Therefore, in the embodiment of FIG. 1, the web wall 3 in which the outermost surface in the vehicle body width direction of the protruding flange portion 6 of the extruded profile 1 is the outermost surface in the vehicle body width direction constituting the closed cross section 8. It is flush with the outer wall surface.

  For comparison, FIG. 6 shows a protruding flange portion 6 in which the protruding flange portion 6 of FIG. 1 protrudes slightly from the inside rather than the outermost portion in the vehicle body width direction of the flange wall 5 constituting the closed section 8. Is shown. Here, also in FIG. 7, the protruding flange portion 6 is moved to the rear side of the vehicle body from a portion slightly inside the vehicle body width direction outermost side of the flange wall 5 (the rear wall 5 in FIG. 1) constituting the closed section 8. The protruding point is the same. 6, 7, and 8, the line indicated by the alternate long and short dash line is the neutral axis of the extruded profile 1.

Hollow section shape of closed section:
The hollow cross-sectional shape itself of the closed cross-sectional portion 8 of the aluminum alloy extruded profile 1 can be manufactured at a low cost by extrusion, and within the design range of the vehicle body seat and other members, as long as the effect of the present invention can be exhibited, You can design freely.

  1 and 2, the closed cross-section portion 8 connects two flange walls 4 and 5 whose wall surfaces extend in parallel to each other in the vehicle body width direction, and these flange walls 4 and 5 are connected to each other. In addition, the wall surface has a rectangular cross section formed by two web walls 2 and 3 extending parallel to each other in the longitudinal direction of the vehicle body.

  The flange wall 5 is a flange wall 5 that extends in the vehicle body width direction, which becomes the rear wall 5 in FIGS. 1 and 2, and a flat plate-like protruding flange portion 6 is extended to the entire length of the closed section 8. In other words, it protrudes toward the side, that is, toward the rear side of the vehicle body in FIGS. Accordingly, the opposite flange wall 4 is the front wall 4 in FIGS. 1 and 2, and the web walls 2 and 3 are the web walls 2 and 3 extending in the longitudinal direction of the vehicle body in FIG.

  On the other hand, the aspect of FIG. 7, 8 has shown the triangular hollow cross-sectional shape other than the rectangular hollow cross-sectional shape of FIG. FIG. 8 shows that the protruding flange portion 6 of the extruded shape member 1 protrudes from the outermost portion in the vehicle body width direction of the rear surface wall 5 of the closed cross-section portion 8 toward the vehicle body rear side, and the protruding flange portion 6 has a vehicle width direction. The outer surface of the web wall 3 is flush with the outer wall surface of the web wall 3 which is the outer wall surface of the closed cross section 8 in the vehicle body width direction. 7 shows the protruding flange portion 6 that protrudes from the inner side in the vehicle body width direction of the flange wall 5 constituting the closed cross-section portion 8 than the protruding flange portion 6 of FIG. .

  9 and 10 are substantially the same in cross-sectional shape as in FIG. 6, but in order to further increase the deformation strength, the inner side of the wall constituting the closed cross-sectional portion 8 is bent when the bending moment acts ( At least a part of the wall located on the left side of each figure is thicker than the thickness of the other walls constituting the closed cross section 8. That is, the flange wall 4 in FIG. 9 and the flange wall 4 and the web 2 in FIG. 10 are thicker than the thickness of the other walls.

  Here, the thickness of the thinnest wall of the closed cross-sectional portion 8 of the aluminum alloy extruded profile according to the present invention is 1.8 mm to 3 mm in consideration of satisfying the necessary strength without hindering weight reduction. A range is preferable.

  11 is substantially the same in cross-sectional shape as in FIG. 6, but in order to further increase the deformation strength, a part of the end of the protruding flange portion 6 of the extruded shape member 1 is denoted by reference numeral 10. , The aspect bent in one direction over the longitudinal direction is shown. Although FIG. 11 shows a mode in which the sheet is uniformly bent over the longitudinal direction by 90 ° in the upward direction, the folding direction may be the opposite downward direction or the diagonal upward or downward direction. Even if it exists, it does not matter including the bending angle. Further, the folding method may not be uniform in the longitudinal direction, and the folding angle and direction may change midway.

How to make the extruded shape of the present invention:
As shown in FIG. 4, the aluminum alloy extruded profile 1 of the present invention is cut into two parts by oblique cutting at one portion of the protruding flange 6 from one material aluminum alloy extruded profile, and the two extruded profiles 1, 1 As can be obtained respectively.

  As described above, when the extruded profile is made of a uniform cross-sectional shape in the longitudinal direction (extrusion direction) (the projecting flange portion having a uniform width in the longitudinal direction and the closed cross-section portion are integrated) In the case where the protruding flange portion of this material extruded shape is cut obliquely to change from narrow to wide, large triangular chips are generated when cutting obliquely, resulting in a very poor material yield. . Therefore, in a shape that is difficult to produce with a variable cross-sectional width by extrusion, such as the extruded shape of the present invention, the difficulty of the production itself becomes a hindrance to the application of the structural member of the extruded shape of the present invention.

  On the other hand, in the present invention, the method of producing such an extruded profile having a variable cross-sectional width is also devised, and the aluminum alloy extruded profile is divided into two parts so that it can be easily obtained.

  That is, the material aluminum alloy extruded shape shown in FIG. 4 has two closed cross-section portions 8 for the extruded shape portion 1 (same as the extruded shape portion 1) arranged in parallel at both end portions. It consists of a flat plate-like flange 6 that is interposed between the closed cross-section portions 6 and 6 and connects them.

  Such a material aluminum alloy extruded shape is extruded as a uniform cross-sectional shape in the longitudinal direction (in the extruding direction) (the cross-sectional shape is the same over the entire length) as usual. And, as shown in FIG. 4, the portion of the protruding flange portion 6 of this material aluminum alloy extruded profile, which has been cut to a predetermined length (long) by a cutter or a shear, is also shown in FIG. Cut in half along the longitudinal direction and bisect. At this time, when the raw material aluminum alloy extruded profile is viewed in plan, it is divided into two so that the shapes of the extruded shapes are point-symmetric with each other, so that two identical extruded profiles 1 can be obtained with high yield.

  Thus, the flange width of the projecting flange portion 6 is narrowed from the end portion 6a to the end portion 6b of the projecting flange portion 6 by obliquely cutting the projecting flange portion 6 along the longitudinal direction. A shape that continuously changes from width to width can be formed. As described above, the change in the flange width of the projecting flange portion 6 may not change continuously in a straight line as shown in FIG. However, the change in the flange width does not change in a linear or arc shape, such as a polygonal line shape or a step shape as shown in FIG. It is difficult to cut and it is difficult to produce the extruded profile of the present invention. Therefore, the shape of the protruding flange portion 6 that changes the flange width is preferably determined from the deformation strength and the ease of cutting.

Usage as a structural member:
4 and 5, 7 provided at various locations on the extruded shape member 1 are bolt fastening through holes provided in the closed cross-section portion 8 and the protruding flange portion 6 of the extruded shape member 1. As described above, if through holes for fastening bolts are provided in the necessary portions of the extruded shape member 1 in advance, joining and fastening with other structural members as structural members becomes easy.

  As a structural member, the material of the member to be joined or combined with the aluminum alloy extruded profile 1 of the present invention is a steel material (ordinary steel, high tensile steel), an aluminum alloy material, a resin material, etc., and the joining method itself is also used. It is selected for convenience such as fusion welding or bolt joining.

  As described above, “with one end as a fulcrum and the other end as an action point” in the manner of applying the composite moment described above is a form of torsional moment and bending load applied to the aluminum alloy extruded profile. The structural member is usually supported or joined at both ends, and these support or joining means are also known by various means such as mechanical joining means such as bolts and welding, as well as fitting to each other. Be joined.

  Therefore, “the one end as a fulcrum and the other end as an action point” is a composite load or moment load form as described above, and these structural members are usually supported or joined at both ends. The supporting or joining state and joining means are not defined or limited.

  In the aluminum alloy extruded profile of the present invention, the thickness of the wall for satisfying the required strength without impairing the weight reduction is the thinnest wall thickness including the closed cross-section portion 8 and the protruding flange portion 6. It is preferable that it is the range of 1.8 mm-3 mm. In order to obtain a high deformation strength under such a thickness condition, the aluminum alloy applied to the extruded profile of the present invention has a high strength of 0.2% proof stress when used as a structural member of 300 MPa or more. It is necessary.

  Such a high-strength aluminum alloy extruded shape has a tempering treatment of T5 or higher (solution treatment, heat treatment such as quenching treatment or artificial aging treatment), high-strength A6000 series or A7000 series. It is preferable to use the aluminum alloy. In other aluminum alloy systems, even if the composition and tempering treatment are adjusted, it is difficult to set the 0.2% proof stress when used as a structural member to be 300 MPa or more. However, the manufacturing cost may increase.

  According to the present invention, even when an aluminum alloy extruded shape is used to reduce the weight of the structural member, a high deformation strength can be obtained with respect to a deformation load composed of the composite moment applied during a vehicle body collision or the like. For this reason, it is suitable for the structural member such as an automobile that requires both weight reduction and deformation strength.

  1: Aluminum alloy extruded profile, 2, 3: Web wall, 4, 5: Flange wall, 6: Protruding flange, 7: Through hole, 8: Closed section, 9: Material aluminum alloy extruded profile

Claims (7)

  An aluminum alloy extruded profile in which a bending load and a torsional moment are applied to one end in the longitudinal direction during use as a structural member, 0.2% proof stress is 300 MPa or more, and a cross section over the entire length A long closed cross-sectional portion having the same shape, and a flat protrusion that protrudes from one wall constituting the closed cross-sectional portion over the entire length of the closed cross-sectional portion in the direction of bending outward when the bending load is applied A shape in which the width of the projecting flange is continuously changed from a narrow width to a wide width from one end side serving as the action point of the closed cross-section portion toward the other end side serving as the fulcrum. An aluminum alloy extruded shape for structural members having a high deformation strength.   2. The aluminum alloy extruded shape for a structural member according to claim 1, wherein one surface of the protruding flange of the aluminum alloy extruded shape is flush with an outer wall surface of one wall constituting the closed cross section.   The aluminum alloy extruded shape for structural members according to claim 1 or 2, wherein the closed section of the aluminum alloy extruded shape has a rectangular sectional shape formed by four walls.   A closed cross-section portion of the aluminum alloy extruded profile is configured, and at least a part of the wall located inside the bend when the bending load is applied is thicker than the thickness of the other walls configuring the closed cross-section portion. The aluminum alloy extruded shape for structural members according to any one of claims 1 to 3.   The aluminum alloy for structural members according to any one of claims 1 to 4, wherein at least a part of an end portion of the protruding flange of the aluminum alloy extruded shape member is bent in one direction along a longitudinal direction thereof. Extruded shape.   The aluminum alloy extruded profile was obtained by bisecting the material aluminum alloy extruded profile, and this material aluminum alloy extruded profile was composed of two parallel sections having the same cross-sectional shape over the entire length. It consists of a long closed cross-section and a flat protruding flange that is interposed between these closed cross-sections and connects the closed cross-sections to each other, and this protruding flange portion is cut obliquely over the longitudinal direction. The aluminum alloy extruded shape for structural members according to any one of claims 1 to 5, wherein the aluminum alloy extruded shape material is bisected so that the shapes thereof are point-symmetric when viewed in plan. Wood.   The aluminum alloy extruded shape for a structural member according to any one of claims 1 to 6, wherein a thickness of a thinnest wall in a closed cross-section portion of the aluminum alloy extruded shape is in a range of 1.8 mm to 3 mm.

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