JP2010064549A - Vehicle body frame member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable an impact to efficiently be absorbed by dispersing a load equally to the whole of a vehicle body frame member to secure stable compressive deformation. <P>SOLUTION: A hat-shaped member 3 and a flat-plate member 9 are joined to each other to form a side member 1 of a closed section structure. Recess/projection parts 29 are each formed on five walls of facing walls 11, 13 facing each other of the hat-shaped member 3, a bottom wall 15 joining the facing walls 11, 13 to each other, and welded and joined walls 25, 27, where flange walls 5, 7 of the hat-shaped member 3 and joining walls 21, 23 of the flat-plate member 9 are welded and jointed respectively. A pair of the walls adjacent to each other on the five walls have the recess/projection parts 29 mutually shifted in phase so that one part becomes a recess while the other one becomes a projection and spot welding points 31 are set on inclined planes 33, which become rising planes of the recess/projection parts 29 from general planes 34 on the welded and joined walls 25, 27. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle body skeleton member that compressively deforms when subjected to an impact load.

  Conventionally, a side member extending in the vehicle longitudinal direction as a vehicle body skeleton member has a closed cross-section with a hat-shaped member having flange surfaces on both sides of a U-shaped cross section and a flat plate member that closes the opening of the hat-shaped member. The structure is known (see Patent Document 1).

And when this side member is provided with a concavo-convex shape portion on three wall portions of a wall portion facing each other in a U-shaped cross section and a wall portion connecting the respective wall portions, when receiving an impact load in the longitudinal direction of the vehicle In addition, the concavo-convex shape portion is positively compressed and deformed to have an impact absorbing function.
JP-A-4-231268

  By the way, the above-mentioned side member is improved in impact absorption efficiency by forming a concave-convex shape portion thereof, a concave portion on one of the three wall portions, and a convex portion on the other. I am trying.

  However, the flange surface that joins and fixes the hat-shaped member and the flat plate member has a flat plate shape and no uneven portion, so that the load cannot be evenly distributed throughout the body frame member and stable. It is difficult to obtain compression (collapse) deformation, and there is a possibility that the shock cannot be absorbed efficiently.

  In view of the above, an object of the present invention is to distribute the load evenly over the entire body skeleton member to ensure stable compression deformation and to efficiently absorb shock.

  The present invention is a vehicle body skeleton member having a first member having a substantially hat-shaped cross section and a second member that is joined to the flange wall portion of the first member to form a closed cross-sectional structure, and the pair of flange walls And a pair of adjacent wall portions in the five wall portions of the first wall portion, the second wall portion, and the third wall portion are out of phase with each other so that one is a concave portion and the other is a convex portion. It has a concavo-convex shape portion, and a welding fixing point is set in an inclined portion of the concavo-convex shape portion of the flange wall portion.

  According to the present invention, one of the pair of adjacent wall portions in the pair of flange wall portions and the five wall portions of the first wall portion, the second wall portion, and the third wall portion is a concave portion and the other is a convex portion. Since it has concavo-convex shapes that are out of phase with each other, the rigidity of the corners that are the boundary portions between the wall portions is improved, and when the vehicle body skeleton member receives a compressive load in the longitudinal direction, The compression deformation promoted by the uneven shape portion is further stabilized.

  At this time, the pair of flange wall portions of the first member are also in phase with each other so that one pair of adjacent wall portions is a concave portion and the other is a convex portion with respect to the first wall portion and the second wall portion. Since the body skeleton member receives a compressive load in the longitudinal direction, the load can be evenly distributed over the entire body to ensure stable compressive deformation and more efficiently. Shock absorption can be performed.

  Further, by setting the welding fixing point on the inclined portion of the flange wall portion, it is not necessary to form a dedicated flat surface for welding on the flange wall portion in order to set the welding fixing point. For this reason, the compressive deformation by forming an uneven | corrugated shaped part also in a flange wall part is made effective, and even if a welding fixing point is set to a flange wall part, an impact absorption function can fully be ensured.

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

  FIG. 1 is a perspective view showing a part of a side member 1 as a vehicle body skeleton member according to the first embodiment of the present invention. The side member 1 is located on both sides of the vehicle bottom in the vehicle width direction. It extends in the longitudinal direction of the vehicle.

  The side member 1 described above includes a hat-shaped member 3 having a hat-shaped cross-sectional shape as a first member, and a closing member for closing the opening of the hat-shaped member 3, and a pair of flange wall portions of the hat-shaped member 3. 5 and 7 are provided with a flat plate member 9 as a second member joined and fixed by spot welding.

  The hat-shaped member 3 is formed, for example, by press-molding a plate material. In addition to the flange wall portions 5 and 7, the first wall portion and the second wall portion that are adjacent to the flange wall portions 5 and 7 and are opposed to each other. The opposite walls 11 and 13 are connected to the opposite ends of the flange walls 5 and 7 of each of the opposite walls 11 and 13, and the third wall extends substantially parallel to the flange walls 5 and 7. And a bottom wall portion 15 as a portion.

  That is, the hat-shaped member 3 that is the first member includes opposing wall portions 11 and 13 that face each other, a bottom wall portion 15 that connects one end portions of the opposing wall portions 11 and 13, and the opposing wall portions 11 and 13. A pair of flange wall portions 5 and 7 extending in the direction opposite to the other end portion side from the other end portion of each one of 13 is provided.

  In the example of FIG. 1, the slopes 17 and 19 are formed so as to chamfer the corners on both sides of the bottom wall part 15, but the slopes 17 and 19 may not be provided. Further, the slopes 17 and 19 will be described hereinafter as being included in the bottom wall portion 15 (a part of the bottom wall portion 15).

  On the other hand, the flat plate member 9 is a single flat plate member, and the bonding wall portions 21 and 23 positioned in the vicinity of both sides in the width direction are overlapped with the flange wall portions 5 and 7 of the hat-shaped member 3 and spotted. Join and fix by welding. The flange wall portions 5 and 7 of the hat-shaped member 3 and the joint wall portions 21 and 23 of the flat plate member 9 in the respective joint fixing portions constitute a pair of weld joint wall portions 25 and 27.

  And the uneven | corrugated shaped part 29 is formed in the appropriate position of the longitudinal direction of the side member 1 shown by the arrow A in FIG. The uneven portion 29 is formed on each of the five wall portions of the pair of opposing wall portions 11 and 13 and the bottom wall portion 15 of the hat-shaped member 3 and the pair of weld joint wall portions 25 and 27.

  Here, in the present embodiment, the concave and convex portions 29 of the five wall portions of the side member 1 are bent so as to have a wave shape in which concave portions and convex portions are repeatedly formed along the longitudinal direction of the side member 1. Forming. At that time, a pair of wall portions adjacent to each other in the five wall portions is formed as a concavo-convex shape portion 29 whose phases are shifted from each other so that one is a concave portion and the other is a convex portion.

  For example, when the welded joint wall 25 and the opposing wall 11 are viewed as a pair of adjacent wall parts, the concave-convex shaped part 29 is the end of the side member 1 on the front side in FIG. From the portion, the concave portion and the convex portion are formed in this order when viewed from the hat-shaped member 3 side, while the opposing wall portion 11 is formed in the order of the convex portion and the concave portion when viewed from the hat-shaped member 3 side.

  Similarly, when the opposing wall portion 11 and the bottom wall portion 15 are seen as a pair of adjacent wall portions, the concave-convex shape portion 29 has the opposite wall portion 11 at the end of the side member 1 on the front side in FIG. The bottom wall 15 is formed in the order of the concave portion and the convex portion as viewed from the hat-shaped member 3 side.

  That is, the concavo-convex shape portion 29 has recesses and projections alternately formed along the respective wall portions in the direction of turning around the plane in the plane orthogonal to the longitudinal direction of the side member 1.

  FIG. 2 is a BB cross-sectional view of the concavo-convex shape portion 29 in the weld joint wall portion 25 of FIG. However, the number of concave portions and convex portions of the concavo-convex shape portion 29 is increased with respect to FIG. In this case, the spot welding point 31 which is a welding fixing point is set on the inclined surface 33 having a wave shape (uneven shape) and is set every two cycles of the wave shape. Such a spot welding spot 31 is set at an appropriate position over the entire length of the weld joint wall portions 25 and 27 including the uneven portion 29.

  The inclined surface 33 described above constitutes an inclined portion that is inclined with respect to a direction perpendicular to the planar general surface 34 in the weld joint wall portions 25 and 27. Therefore, the spot welding spot 31 is set on the inclined surface 33 of the uneven portion 29 from the general surface 34 in the weld joint walls 25 and 27.

  Further, the concave and convex portion 29 where the spot welding spot 31 of the weld joint wall portions 25 and 27 is set is a portion corresponding to the flange wall portions 5 and 7 of the hat-shaped member 3 and the flange wall portions 5 and 7. A gap 35 is formed between the joining wall portions 21 and 23 of the flat plate member 9.

  The side member 1 having such a structure receives a load in a direction in which the side member 1 is compressed in the longitudinal direction by receiving an impact load in the vehicle longitudinal direction. At this time, since the uneven portion 29 is set in the side member 1, stress concentrates on the uneven portion 29 and is easily compressed and deformed (axial collapse) in the longitudinal direction to absorb the impact load.

  Here, in the present embodiment, in setting the above-described concavo-convex shape portion 29, a pair of adjacent walls 11 and 13 and the bottom wall portion 15 and the five wall portions of the weld joint wall portions 25 and 27 are adjacent to each other. Since the wall portions of the wall portions have concave and convex shapes that are out of phase so that one is a concave portion and the other is a convex portion, a corner portion (in this embodiment, a slope 17) is a boundary portion between the wall portions. , 19), and the compression deformation promoted by the concavo-convex shape portion 29 is further stabilized when receiving a compressive load in the axial crushing direction.

  For example, when a pair of adjacent wall portions are not out of phase with respect to the shape of the concavo-convex portion as in the present embodiment, and both are only convex portions or only concave portions, The rigidity is low, for example, the square closed section is deformed so as to be distorted in a rhombus.

  Moreover, in this embodiment, also about the welding joining wall parts 25 and 27, between the opposing wall parts 11 and 13 which are adjacent wall parts, a phase shift | offset | difference mutually mutually so that one becomes a recessed part and the other becomes a convex part. Since the concavo-convex shape portion 29 is used, when an impact load is applied, the load is evenly distributed over the entire side member 1, and stable compression deformation can be secured, so that the shock can be absorbed more efficiently.

  Furthermore, in this embodiment, as shown in FIG. 2, since the spot welding hit points 31 in the welded joint walls 25 and 27 are set to the wave-shaped inclined surface 33, the spot welding hit points 31 are set. It is not necessary to form a dedicated flat surface for welding on the weld joint walls 25 and 27. For this reason, the compressive deformation by providing the concavo-convex shape portion 29 is made effective, and even if the spot welding hit points 31 are set on the weld joint wall portions 25 and 27, the impact absorbing function can be sufficiently secured.

  Moreover, in this embodiment, as shown in FIG. 2, the spot-welding spot 31 in the welding joint wall parts 25 and 27 is set for every two cycles of a wave shape. At this time, by setting the spot welding hit point 31 at the center of the inclined surface 33 in the inclined length direction, the spot weld hitting point 31 between the upper hat-shaped member 3 and the lower flat plate member 9 in FIG. The lengths along the wave shape between each other can be made substantially equal.

  Thereby, when receiving the impact load in the compression direction, the hat-shaped member 3 and the flat plate member 9 having the same length between the spot welding hit points 31 are compressed almost uniformly, and the spot welding hit points 31 are moved to. Stress concentration can be reduced, and compression deformation can be efficiently performed while ensuring a stable welded state.

  In the above-described example, the spot welding hit points 31 in the weld joint walls 25 and 27 are set every two cycles of the wave shape, but may be set every three cycles or more. In short, the hat-shaped member 3 and the flat plate member 9 need only be able to have substantially the same length along the wave shape between the spot welding points 31. For this reason, the above lengths should theoretically be equal even in each cycle. However, since it is extremely difficult in practice, it is desirable to set at least every two cycles.

  In addition, as shown in FIG. 2, by providing gaps 35 between the hat-shaped member 3 and the flat plate member 9 in the concavo-convex shape portions 29 of the weld joint walls 25 and 27, the positions of a plurality of spot welding hit points 31 are provided. It is possible to absorb the deformation difference between the members 3 and 9 when the variation occurs, and to efficiently ensure the compression deformation described above.

  FIG. 3 is a cross-sectional view corresponding to FIG. 2, showing a second embodiment of the present invention. In the second embodiment, the concavo-convex shape portions 29 in the weld joint walls 25 and 27 in FIG. 2 are formed in a shape that is entirely laid in the wave forming direction (right direction in FIG. 2). As a result, the inclined surfaces 37 and 39 on both sides of the concave-convex shaped portion 29 are made different from each other at the concave portion or the apex of the convex portion, and the inclined surface 37 in which the spot welding hit points 31 are set here. Is inclined more gently than the inclination angle of the inclined surface 39.

  Therefore, when spot welding is performed on the concave and convex portions 29 of the weld joint walls 25 and 27, a spot welding gun (not shown) may be brought close to the inclined surface 37 having a gentler inclination. Compared with the case where the spot welding gun is brought closer to the tight inclined surface 39, the workability is improved, which can contribute to the improvement of productivity.

  FIG. 4 is a reaction force characteristic diagram when the side member 1 which is a vehicle body skeleton member receives the impact load. The solid line corresponds to each embodiment of the present invention, and the broken line corresponds to the conventional structure. According to this, in the embodiment of the present invention, it can be seen that the reaction force is reduced compared with the conventional case when the impact load is initially received, and the load absorption performance in the initial stage of the collision is improved.

  In the above embodiments, the side member 1 is described as an example of the vehicle body skeleton member. However, the vehicle body skeleton member is not limited to the side member 1 as long as it is a vehicle body skeleton member that receives a compressive load in the axial direction (longitudinal direction).

It is a perspective view which shows a part of side member concerning the 1st Embodiment of this invention. It is BB sectional drawing of FIG. It is sectional drawing corresponding to FIG. 2 which shows the 2nd Embodiment of this invention. It is a reaction force characteristic figure of the body frame member of the present invention and the conventional structure.

Explanation of symbols

1 Side member (body frame member)
3 Hat-shaped member (first member)
5, 7 Flange wall portion of hat-shaped member 9 Flat plate member (second member)
11 Hat-shaped member facing wall (first wall)
13 Hat-shaped member facing wall (second wall)
15 Bottom wall portion of hat-shaped member (third wall portion)
29 Concavity and convexity part 31 Spot welding spot (welding fixed point)
33 Inclined surface (inclined part)
35 Clearance 37 Slope with gentle slope

Claims (5)

  The first wall portion and the second wall portion facing each other, the third wall portion connecting one end portions of the first wall portion and the second wall portion, and each one of the first wall portion and the second wall portion A first member having a substantially hat-shaped cross section including a pair of flange wall portions extending in a direction opposite to the other end portion side from the other end portion of the first member, and the flange wall portion of the first member. A vehicle body skeleton member having a second member that forms a closed cross-sectional structure together with the first member, wherein the pair of flange wall portions, the first wall portion, the second wall portion, and the third wall portion A pair of adjacent wall portions in the five wall portions have concavo-convex shape portions that are out of phase so that one is a concave portion and the other is a convex portion, and the concavo-convex shape portion of the flange wall portion is inclined. A vehicle body skeleton member characterized in that a welding fixing point is set at a portion.   The concave and convex portion has a wave shape in which a concave portion and a convex portion are repeatedly formed along the longitudinal direction of the vehicle body skeleton member, and at least two cycles in a direction in which the concave portion and the convex portion of the wave shape are repeatedly formed. The vehicle body skeleton member according to claim 1, wherein the welding fixing point is set every time.   The inclined part has different inclination angles of the inclined parts on both sides of the concave part or the convex part as a boundary, and is fixed to the inclined part with a gentle inclination among the inclined parts having different inclination angles. The vehicle body skeleton member according to claim 1, wherein a point is set.   4. The gap according to claim 1, wherein a gap is provided between a flange wall portion of the first member and the portion of the second member corresponding to the flange wall portion of the second member. The vehicle body frame member according to claim 1.   The vehicle body skeleton member according to any one of claims 1 to 4, wherein the vehicle body skeleton member is a side member that extends in the vehicle front-rear direction at both sides in the vehicle width direction.

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