JPH11208505A - Vehicle side member connection structure - Google Patents

Abstract

(57) Abstract: A vehicle side member connecting structure capable of reducing the amount of deformation of a cross member at the time of a collision of a vehicle and reducing the deformation of a member connected thereto. SOLUTION: Since the rotation center A of the side member 6 and the torsion center B of the cross member 9 coincide with each other, even in the case of a frontal collision where a collision load is applied to the front end of the side member 6,
The cross member 9 rotates only around the torsion center B, and does not move in the vertical or front-rear direction. Therefore, the amount of deformation of the cross member 9 can be small, and the amount of deformation of the instrument stay 15 attached to the cross member 9 can be small.
Repair is easy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle side member connecting structure.

[0002]

2. Description of the Related Art As a conventional side member connecting structure of a vehicle, for example, as disclosed in Japanese Patent Application Laid-Open No. 6-144299, a dash panel is mounted on front and rear side members disposed on the right and left sides of a vehicle body. Are connected by a cross member joined to the lower side along the vehicle width direction.

[0003]

However, in such a conventional technique, the center of rotation of the side member at the time of collision and the center of torsion of the cross member are offset from each other in a side view. Due to the deformation of the side member around the rotation center at the time of the collision of the vehicle, the cross member moves in the front-back direction or the up-down direction. for that reason,
The amount of deformation of the cross member and the members attached thereto is large, and repair is troublesome.

The present invention has been made by paying attention to such a conventional technique, and it is possible to reduce the amount of deformation of a cross member at the time of a collision of a vehicle and to reduce the deformation of a member connected thereto. An object of the present invention is to provide a vehicle side member connection structure.

[0005]

According to the first aspect of the present invention,
In a vehicle side member connecting structure in which front and rear side members arranged on both right and left sides of a vehicle body are connected by a cross member along a vehicle width direction, a rotation center at the time of collision of the side member and a torsion of the cross member are provided. The center coincides with the side view.

According to a second aspect of the present invention, an upper end portion of the instrument stay is connected to a steering member supporting the steering column, and a lower end portion of the instrument stay is connected to a torsion center of the cross member.

According to a third aspect of the present invention, a brace passing through the center of torsion is provided in the cross member, and the lower end of the instrument stay is connected to the center of torsion in the brace.

According to a fourth aspect of the present invention, the side member is formed by joining the rear end of the front side member and the front end of the floor side member, and the center of rotation of the side member is defined by the front side member and the floor side. The intersection of the joining surface of the member and the vertical center line of the front side member.

According to a fifth aspect of the present invention, the torsion center of the cross member having a rectangular cross section when joined to the lower side of the panel is defined as the intersection of the diagonal lines of the cross member.

According to a sixth aspect of the present invention, the instrument stay has at least one or more bendable portions in response to an input associated with a vertical movement or a forward / backward movement.

According to a seventh aspect of the present invention, the bent portion is formed by a joint of an upper instrument stay and a lower instrument stay each having a U-shaped cross section, and a lower end of the upper instrument stay is a flange having a flat plate cross section, The upper end of the lower instrument stay is a bent portion, and only the flange of the upper instrument stay is connected to the bent portion of the lower instrument stay.

According to an eighth aspect of the present invention, a notch or a bead is formed at the base of the flange of the upper instrument stay.

[0013]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. Reference numeral 1 denotes a dash panel, which is a wall member that partitions the engine room E and the vehicle interior R. A slightly curved inclined portion 2 is formed below the dash panel 1, and a flat portion 4 connected to the floor panel 3 is also formed at the rear end of the inclined portion 2. A pair of left and right through holes 5 is formed from the inclined portion 2 to the flat portion 4.

Reference numeral 6 denotes a pair of left and right side members extending in the front-rear direction. The front side member 7 is located in the engine room E and is coupled to the inclined portion 2 of the dash panel 1 with the rear portion slightly curved. Front side member 7
And a floor side member 8 whose front end is joined to the rear end and which is joined to the lower surface of the floor panel 3.

As shown in FIG. 3, a joint surface between the front side member 7 and the floor side member 8 and a vertical center line L connecting the upper and lower half (h / 2) of the height h of the front side member 7 are formed. Is the center of rotation A at the time of a frontal collision of the side member 6.

On the lower surface of the inclined portion 2 of the dash panel 1,
A cross member 9 having a substantially inverted hat shape in cross section is attached along the vehicle width direction. The cross member 9 is attached to the dash panel 1 to form a closed cross section. The left and right side members 6 are formed by the cross members 9.
Are connected in the vehicle width direction.

The torsion center B of the cross member 9 is, as shown in FIG. 4, an intersection of diagonal lines of the cross-sectional shape of the cross member 9, and the torsion center B corresponds to the rotation center A of the side member 6 and They match in side view.

A brace 10 that forms a closed cross section with the cross member 9 is attached to the upper surface of the center of the cross member 9. At the upper surface of the brace 10, mounting holes 11 with welding nuts are formed on the left and right, and the mounting holes 11 correspond to the through holes 5 formed on the dash panel 1, respectively. The upper surface of the brace 10 coincides with the torsion center B of the cross member 9 in a side view.

A steering wheel 13 is provided at the upper end of the steering column 12, and the steering column 12 is supported by a steering member 14 arranged along the vehicle width direction. Steering member 14
Is supported by the bent portion H by an instrument stay 15 having an overall shape bent in a U-shape. The instrument stay 15 includes an upper instrument stay 16 and a lower instrument stay 17.

As shown in FIG. 5, the upper instrument stay 16 and the lower instrument stay 17 each have a U-shaped cross section, and the upper end of the upper instrument stay 16 is connected to the steering member 14. The bent portion H of the instrument stay 15 includes a flat plate-shaped flange 18 formed at the lower end of the upper instrument stay 16 and a "<"-shaped bent portion 19 formed at the upper end of the lower instrument stay 17.
Is formed by the connecting portion. A notch 20 is provided at the base of the flange 18 at the lower end of the upper instrument stay 16.
(A bead is also acceptable), and only the flange 18 is joined to the bent portion 19 of the lower instrument stay 17.

The lower end of the instrument stay 15 is inserted through a through hole 5 formed in the dash panel 1 and is inserted into a mounting hole 11 with a welding nut of a brace 10 provided inside the cross member 9 by a bolt / nut means 21. Fixed.

Next, the operation will be described. When a collision load F is applied to the front end of the front side member 7 due to a frontal collision of the vehicle, a moment is generated around the rotation center A on the side member 6 and the side member 6 is deformed from the rotation center A. At this time, since the rotation center A of the side member 6 and the torsion center B of the cross member 9 coincide with each other, even in the case of a full collision in which a collision load F is applied to both side members 6, only one of the side members 6 is used. In the case of an offset collision in which a collision load F is applied to the cross member, the cross member only rotates around the torsion center B and does not move up and down or back and forth. Therefore, the deformation of the cross member 9 is small, and the repair is easy.

Further, since the rotation center A of the side member 6 and the torsion center B of the cross member 9 coincide with each other, the torsional rigidity of the cross member 9 is mainly the bending rigidity of the side member 6 at the time of an offset collision of the vehicle. And the amount of deformation of the side member 6 itself can be reduced.

Further, since the lower end of the instrument stay 15 is connected to the brace 10 passing through the torsion center B of the cross member 9, the cross member 9 is twisted with the rotation due to the deformation of the side member 6 at the time of vehicle collision. Since the moment M for rotating the instrument stay 15 downward is generated, it is possible to suppress the steering column 12 from jumping upward.

For example, in the case of an offset collision, if the torsion deformation of the cross member 9 with respect to the side member 6 on the non-collision side is φ and the rotation angle of the side member 6 is θ, the rotation angle of the instrument stay 15 is (θ− φ). Than this,
Since a moment M for rotating the steering column 12 downward is generated in the instrument stay 15, it is possible to suppress the steering column 12 from jumping upward.

In addition, the torsion center B is provided in the cross member 9.
Is provided, the out-of-plane deformation of the cross member 9 at the time of a vehicle collision can be prevented, and the torsional rigidity can be improved. That is, it is difficult to transmit the deformation of the side member 6 at the time of the collision to the steering member 14 via the instrument stay 15, and the steering member 1
4 can be greatly reduced. Furthermore, the side member 6
The displacement of the attachment point of the instrument stay 15 can be made extremely small with respect to the input from the driver, so that the input to the steering member 14 can be reduced, and the sound vibration is also advantageous.

The instrument stay 15 has a bent portion H
Therefore, stable bending deformation can be generated while having an out-of-plane rigidity required for installing the audio operation unit and the like. That is, as described above, the lower end portion of the instrument stay 15 is deformed by the load at the time of collision, and the moment M for lowering the steering column 12 is generated in the instrument stay 15. A bending input acts on the upper instrument stay 16 with respect to the moment M in this direction. However, since the upper instrument stay 16 has a U-shaped cross section, sufficient bending rigidity is obtained. In this case, if the upper and lower U-shaped cross sections have a large lap allowance in the bent portion H, which is a connecting portion between the upper instrument stay 16 and the lower instrument stay 17,
The bent member H is not easily broken, and the side member 6 is not broken.
The torque input of the lower instrument stay 17 due to the rotation of the shaft can be transmitted to the steering column 12 through the steering member 14 in a favorable manner.

On the other hand, only the flange 18 of the upper instrument stay 16 is connected to the bent portion 19 of the lower instrument stay 17 and the notch 20 is formed at the base of the flange 18. Only the moment M that causes the steering column 12 to rotate downward can be transmitted, and the load that causes the steering column 12 to jump upward is not transmitted because the flange 18 is bent from the notch 20.

In the above embodiment, the dash panel 1 having a substantially inverted hat-shaped cross section has been taken as an example. In general, the centroid of a member having an arbitrary cross section is mathematically defined as shown in FIG.
However, since such a mathematical definition is abstract and difficult to understand, in the case of the square cross section 22, the intersection of the diagonal lines may be the torsion center B as in the above embodiment (see FIG. 7). In the case where the cross section of the cross member is, for example, a pentagonal cross section 23 having an odd number of vertices, a closed polygon constituted by five straight lines passing through the vertex and bisecting the opposite side facing the vertex. May be set to the torsion center B (see FIG. 8). Further, in the case where the cross section of the cross member is a hexagonal cross section 24, the centroid of a triangle composed of three diagonal lines connecting opposing vertices (a point at which a bisector of an arbitrary vertex is divided into 2: 1)
(See FIG. 9).

In the embodiment, the side member 6 on the front side of the vehicle is taken as an example. However, the present invention can be applied to a rear side member (rear side member) on the vehicle.

[0031]

According to the first aspect of the present invention, the center of rotation of the side member and the center of torsion of the cross member coincide with each other. The member only rotates around the center of torsion and does not move in the up / down or front / back direction. Therefore, the amount of deformation of the cross member can be small, and the amount of deformation of the member attached to the cross member can be small, so that the repair is easy. Further, since the rotation center of the side member and the torsion center of the cross member coincide with each other, the torsional rigidity of the cross member mainly increases the bending rigidity of the side member at the time of an offset collision of the vehicle, and the side member itself. Can also be reduced.

According to the second aspect of the present invention, since the lower end of the instrument stay is connected to the center of torsion of the cross member, the cross member is twisted with the rotation due to the deformation of the side member during a vehicle collision, and Since a moment for rotating the stay in the downward direction is generated, it is possible to suppress the steering column from jumping upward. In addition, rotation of the instrument stay in the left-right direction is also suppressed.

According to the third aspect of the present invention, by providing a brace passing through the center of torsion in the cross member,
Prevents out-of-plane deformation of the cross member during a vehicle collision,
The torsional rigidity can be improved. Further, since the torsional rigidity is improved, the sound vibration performance of the vehicle body is also improved.

According to the fourth aspect of the present invention, if the intersection between the joint surface between the front side member and the floor side member and the vertical center line of the front side member is selected as the center of rotation of the side member, it is structurally practical. Approximately coincides with the rotation center of.

According to the fifth aspect of the present invention, if the intersection of the diagonal lines is selected as the torsion center of the cross member, the torsion center substantially matches the actual torsion center.

According to the sixth aspect of the present invention, since the instrument stay has at least one bent portion, out-of-plane rigidity required for installing an audio operation unit or the like on the instrument stay is provided. , It is possible to generate stable bending deformation.

According to the seventh aspect of the present invention, since only the flange of the upper instrument stay is connected to the bent portion of the lower instrument stay, it is possible to generate a more stable folding deformed portion while providing the necessary rigidity to the instrument stay. Can be.

According to the eighth aspect of the present invention, since the notch or the bead is formed at the base of the flange of the upper instrument stay, the instrument stay can be more easily broken.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a vehicle body front portion showing a vehicle side member connection structure according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the behavior of the instrument stay when a load is applied during a frontal collision of the vehicle body.

FIG. 3 is a side view showing a rotation center position of a side member.

FIG. 4 is a side view showing a torsion center position of the cross member.

FIG. 5 is an enlarged perspective view showing a bent portion of the instrument stay.

FIG. 6 is a diagram showing a centroid of an arbitrary cross-sectional shape.

FIG. 7 is a diagram showing a torsion center of a rectangular section.

FIG. 8 is a diagram showing a torsion center of a pentagonal cross section.

FIG. 9 is a diagram showing a torsion center of a hexagonal cross section.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Dash panel 6 Side member 7 Front side member 8 Floor side member 9 Cross member 10 Brace 12 Steering column 13 Steering wheel 14 Steering member 15 Instrument stay 16 Upper instrument stay 17 Lower instrument stay A Center of rotation B Center of twist E Engine room F Collision Load H Bending part M Moment R Car interior

Claims (8)

[Claims] 1. A side member connecting structure for a vehicle in which front and rear side members disposed on both right and left sides of a vehicle body are connected by a cross member along a vehicle width direction, wherein a rotation center of the side member at the time of collision is provided. And a torsion center of the cross member coincides in a side view. 2. The vehicle side member according to claim 1, wherein an upper end of the instrument stay is connected to a steering member supporting the steering column, and a lower end of the instrument stay is connected to a torsion center of the cross member. Connection structure. 3. The vehicle side member connecting structure according to claim 2, wherein a brace passing through the center of torsion is provided in the cross member, and a lower end portion of the instrument stay is connected to the center of torsion in the brace. 4. A side member is formed by joining a rear end of a front side member and a front end of a floor side member, and a center of rotation of the side member is defined by a joint surface between the front side member and the floor side member; The vehicle side member connection structure according to any one of claims 1 to 3, wherein the intersection is an intersection of a vertical center line of the front side member. 5. The vehicle side according to claim 1, wherein a torsion center of the cross member having a rectangular cross section when joined to the panel is an intersection of diagonal lines of the cross member. Member connection structure. 6. The vehicle according to any one of claims 1 to 5, wherein the instrument stay has at least one or more bending portions in response to an input accompanying vertical movement or front-back movement. Side member connection structure. 7. A bent portion is formed by a joint of an upper instrument stay and a lower instrument stay each having a U-shaped cross section, a lower end of the upper instrument stay is a flange having a flat plate cross section, and an upper end of the lower instrument stay. 7. The side member connecting structure for a vehicle according to claim 6, wherein is a bent portion, and only the flange of the upper instrument stay is connected to the bent portion of the lower instrument stay. 8. The vehicle side member connecting structure according to claim 7, wherein a notch or a bead is formed at a root of the flange of the upper instrument stay.