JP2006151145A - Lower bodywork of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lower bodywork of a vehicle equipped with an enhanced rigidity of its suspension member by enabling dispersion of the lateral input acting on the suspension member into the vehicle width direction and the longitudinal direction of the vehicle. <P>SOLUTION: The lower bodywork of the vehicle is structured so that the vehicle body 12 is installed over a pair of front side members 11 and is equipped with the suspension member 23, a pair of tunnel members 14 to form a closed section together with a floor panel 13, and a bracket 15 coupling the front of the tunnel members 14 with the rear of the suspension member 23, wherein the mounting part of the suspension member 11 to the body 12 has a pair of first mounting parts 24b for mounting the bracket 15 on the suspension member 23 in the position where the the extension line of the tunnel members intersects the suspension member and a pair of second mounting parts 24c for mounting the suspension member on the undersurface of the front side member, and it is arranged so that the first mounting parts and the second mounting parts 24c are located separately from each other in the vehicle width direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a lower vehicle body structure for attaching a suspension member for supporting a front suspension of a vehicle to a vehicle body.

2. Description of the Related Art Conventionally, there is known a lower vehicle body structure provided with a plane U-shaped subframe (suspension member) for supporting a front suspension of a vehicle. In this lower body structure, a transverse member extending in the vehicle width direction of the vehicle body is connected to both ends of the rear portion of the suspension member, and a first attachment portion in which the suspension member and the transverse member are fastened together with the vehicle body, and the vehicle longitudinal direction On the other hand, a transverse attachment member is attached to the vehicle body alone at a position behind the first attachment portion (see, for example, Patent Document 1).
JP 2003-118630 A

  However, in the conventional lower vehicle body structure described above, the first and second mounting portions are provided in the front-rear direction of the vehicle, so that only the input in the vehicle width direction is input to the suspension member and the transformer with respect to the lateral input from the wheels. Bath members will receive.

  In order to increase the strength against the input in the vehicle width direction, it is necessary to improve the lateral rigidity of the suspension member and the transverse member. For this reason, if the suspension member and the transverse member are enlarged, the mass of the lower body structure of the vehicle increases. There was a problem inviting.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a lower body structure of a vehicle that can reduce lateral input by dispersing lateral input from wheels in the vehicle width direction and the vehicle longitudinal direction. .

The present invention has been made in view of the above circumstances, and has a pair of left and right front side members arranged in the front-rear direction of a vehicle, and a substantially rectangular frame-like shape attached to the lower part of the pair of front side members. A pair of tunnel members, which are disposed along the vehicle body longitudinal direction inside the front side member and formed in the front side member, and which form a closed section with a floor panel connected to the dash panel of the vehicle body; A lower body structure of a vehicle including a bracket connecting a front portion and a rear portion of the suspension member,
A mounting portion between the suspension member and the front side member includes a pair of first mounting portions for mounting the bracket to the suspension member at a position where an extension line of the tunnel member intersects the suspension member, and the front A pair of second attachment portions for attaching the suspension member to the lower surface of the side member, and the first attachment portion and the second attachment portion are spaced apart from each other in the vehicle width direction. It is characterized by that.

  According to the present invention, the suspension member is attached to the vehicle body with the pair of first attachment portions for attaching the bracket to the suspension member at a position where the extension line of the tunnel member intersects the suspension member, and the lower surface of the front side member. A pair of second mounting portions for mounting the suspension member is used, and the first mounting portion and the second mounting portion are disposed apart from each other in the vehicle width direction, so that the lateral input from the wheel Can be dispersed in the vehicle width direction and the vehicle front-rear direction, and the input in the vehicle width direction to the suspension member can be reduced.

  Hereinafter, a lower body structure of a vehicle according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows a bottom view of the lower body structure of the vehicle 10.

  In FIG. 1, 11 and 11 denote a pair of left and right front side members that extend in the longitudinal direction of the vehicle and are arranged on the left and right of the vehicle 10, and 13 denotes a floor panel of the vehicle body 12.

  Inside the front side members 11, 11, a pair of tunnel members 14, 14 that form a closed section integrally with the floor panel 13 are provided. Brackets 15 and 15 are integrally attached to the front portions of the tunnel members 14 and 14, respectively.

  In FIG. 2, a dash panel 16 is attached to the front side of the floor panel 13, and the front portion of the dash panel 16 has a front surface portion 16 a that rises upward. The bracket 15 has a front surface portion 15 a rising from a corner portion, and the front surface portion 15 a is connected to the front surface portion 16 a of the dash panel 16 at a joint portion 17 on substantially the same surface.

  As shown in FIG. 3, the bracket 15 has a vehicle inner vertical wall portion 15 b connected to the dash panel 16, and the vehicle inner vertical wall portion 15 b is joined to a tunnel vertical wall portion 16 b provided on the dash panel 16. The portions 18 are connected on substantially the same plane.

  As shown in FIG. 3, the bracket 15 is connected to the front side member 11 at a joint portion 19. A reinforcing member 20 is provided between the joint portion 18 and the joint portion 19 of the bracket 15. Further, as shown in FIG. 2, a reinforcing member 21 is provided at a corner portion formed at the front portion of the bracket 15.

  In FIG. 1, a suspension member 23 is disposed in front of the vehicle body 12. The front portion of the suspension member 23 is attached to the lower surfaces 11a and 11a of the front side members 11 and 11 at the left and right attachment portions 24a and 24a, respectively.

  As shown in FIG. 5, the suspension member 23 includes a front cross portion 23a, a pair of vertical piece portions 23b and 23b that rise upward from the left and right sides of the front cross portion 23a, and rear ends of the vehicle from each end of the front cross portion 23a. Are formed by side member portions 23c, 23c extending rearward and a rear cross portion 23d extending in the vehicle width direction from the rear ends of the side member portions 24c, 24c.

  The attachment portions 24a and 24a are provided on the upper portions of the vertical piece portions 23bb and 23b, respectively.

  As shown in FIGS. 1 and 5, an engine mount (not shown) is attached to the attachment portion 25 provided in the central portion of the rear cross portion 23d. Stiffening portions 26 and 26 are respectively provided at the corner portions formed by the side member portions 23c and 23c and the rear cross portion 23d.

  The stiffening portions 26 and 26 are formed such that the cross sections of the stiffening portions 26 and 26 are enlarged as the rear crossing portion 23d is approached.

  Thus, by providing the stiffening portion 26 at the corner portion between the side member portions 23c, 23c of the suspension member 23 and the rear cross portion 23d, the strength of the rear cross portion 23d is improved and the auxiliary portion provided at the corner portion is also provided. Since the cross-section change rate of the rigid portion 26 is small, when the external force is input to the suspension member 23, the bending of the members such as the side member portions 23c, 23c and the rear cross portion 23d can be suppressed, and the energy of the suspension member 23 can be suppressed. Absorption efficiency can be improved.

  In general, when an external force is applied to the suspension member 23, it is known that if the cross-section change rate of the suspension member 23 is large, the energy absorption efficiency is lowered due to the occurrence of breakage from that portion.

  Since the stiffening portion 26 of the suspension member 23 in the present embodiment is formed so that the cross section expands as it approaches the rear cross portion 23d from the side member portion 23c, that is, the cross section change rate becomes small. Occurrence of bending in the stiffening portion 26 having a large cross section can be suppressed.

  Further, as shown in FIG. 5, the stiffening portions 26, 26 have the lower surfaces 26a, 26a of the stiffening portions 26, 26 substantially flush with the lower surfaces 23e, 23e of the side member portions 23c, 23c of the suspension member 23. And the upper surfaces 26b, 26b of the stiffening portions 26, 26 are formed so as to enlarge the cross section of the stiffening portions 26, 26 as they approach the rear cross portion 23d.

  By configuring the stiffening portions 26, 26 as described above, when an external force is applied to the suspension member 23, a mode in which members such as the side member portions 23c, 23c and the rear cross portion 23d are bent downward is suppressed. And energy absorption efficiency can be improved.

  Next, attachment of the suspension member 23 to the front side members 11 and 11 and the vehicle body 12 will be described.

  In FIG. 1 and FIG. 5, the attachment portions 24b and 24b as the first attachment portions of the suspension member 23 are located at a separated position where the forward extension line of the tunnel member 14 intersects the rear cross portion 23d. In the mounting portions 24b and 24b, the brackets 15 and 15 and the rear cross portion 23d are connected by bolts 27 as shown in FIG.

  Further, a pair of attachments as a second attachment part for attaching the suspension member 23 to the lower surfaces 11a, 11a (see FIGS. 1 and 3) of the front side members 11, 11 are attached to the side member part 23c of the suspension member 23. Portions 24c and 24c are provided.

  As shown in FIG. 3, the side member portions 23c and 23c of the suspension member 23 are fixed to the front side member 11 by bolts 28 at the positions of the mounting portions 24c and 24c. Further, the mounting portions 24b, 24b and the mounting portions 24c, 24c are spaced apart from each other and are arranged in the vehicle width direction.

  In this way, by attaching the suspension member 23 to the vehicle body 12 (see FIG. 1) along the vehicle width direction of the vehicle body 12, lateral input acting on the suspension member 23 can be applied to the vehicle width direction and the vehicle front-rear direction. Thus, the vehicle width direction input to the suspension member 23 can be reduced.

  The suspension member 23 shown in FIG. 1 is provided with a front suspension (not shown) that holds wheels (not shown), and the front portion of the vehicle body 12 is supported via the front suspension. Further, the wheel is disposed outside the front cross portion 23 a of the suspension member 23.

  Next, the operation of this embodiment will be described.

  In FIG. 1, when an external force Fa in the vehicle width direction indicated by an arrow 30 is input to the suspension member 23 from a wheel (front wheel) (not shown), a moment M 1 is generated at the front portion of the vehicle body 12.

  The first attachment portions 24b and 24b between the suspension member 23 and the vehicle body 12 and the second attachment portions 24c and 24c between the suspension member 23 and the front side members 11 and 11 are arranged apart from each other in the vehicle width direction. Therefore, the external force Fa acting on the suspension member 23 in the lateral direction can be dispersed into a vehicle width direction force F1 indicated by an arrow 31 and a vehicle front-rear direction force F2 indicated by an arrow 32.

  As a result, the support rigidity of the front suspension by the suspension member 23 can be increased without increasing the weight of the suspension member 23.

  On the other hand, an engine mount (not shown) is attached to the attachment portion 25 of the rear cross portion 23d of the suspension member 23. As shown in FIG. 3, the vertical input Fb from the engine mount indicated by the arrow 33 is input to the rear cross portion 23 d of the suspension member 23.

  In the present embodiment, as shown in FIG. 2, the front surface portion 15a of the bracket 15 and the front surface portion 16a of the dash panel 16 are connected on substantially the same surface. In addition, the rigidity of the engine mount in the vertical direction can be improved by being received by the bending action of the dash panel 16 and being distributed and transmitted in the plane of the bracket 15 and the dash panel 16.

  Further, in FIG. 3, the vehicle interior vertical wall portion 15 b of the bracket 15 is connected to the tunnel vertical wall portion 16 b of the dash panel 16 on substantially the same plane, so that the vertical input Fb from the engine mount is connected to the vehicle of the bracket 15. It is received by the bending action of the inner vertical wall portion 15b and the tunnel vertical wall portion 16b of the dash panel 16, and is distributed and transmitted in the plane of the vehicle inner vertical wall portion 15b of the bracket 15 and the tunnel vertical wall portion 16b of the dash panel 16. Thus, the vertical rigidity of the engine mount can be improved.

  Normally, when the external force Fa from the direction of the arrow 30 is input to the suspension member 23 shown in FIG. 1, if the cross-section change rate of the suspension member 23 is large, the suspension member 23 is broken and the suspension member 23 absorbs energy. Efficiency will decrease.

  However, in the present embodiment, the stiffening portion 26 provided at the corner portion of the side member portion 23c and the rear cross portion 23d is formed so that the cross section expands as it approaches the rear cross portion 23d. The occurrence of breakage of the member 23 can be suppressed.

  When an external force from the front is input to the suspension member 23 shown in FIG. 1, a moment M2 is generated on the front side of the suspension member 23 as shown in FIG. Fold mode occurs.

  However, in this embodiment, the lower surface 26a of the stiffening portion 26 is connected to the lower surface 23e (see FIG. 5) of the side member portions 23c, 23c of the suspension member 23 in substantially the same plane, and stiffening is performed as the rear cross portion 23d is approached. Since the upper surface 26b of the stiffening portion 26 is formed so that the cross section of the portion 26 is enlarged and the lower surface 26a of the stiffening portion 26 is widened, members such as the side member portions 23c and 23c and the rear cross portion 23d are formed. Can be suppressed from being bent downward, and the energy absorption efficiency of the suspension member 23 can be improved.

It is a top view of the lower vehicle body structure of the vehicle concerning embodiment of this invention. FIG. 2 is a cross-sectional view taken along line AA in FIG. 1. It is a BB sectional view taken on the line in FIG. It is a side view which shows the frame structure of the vehicle front part concerning embodiment of this invention. It is a perspective view of a suspension member concerning an embodiment of the invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Vehicle 11 Front side member 11a Lower surface 12 of front side member Car body 13 Floor panel 14 Tunnel member 15 Bracket 15a Front part 1 of bracket
16 dash panel 16a front part 23 of dash panel suspension member 23a front cross part 23c side member part 23d rear cross part 23e lower surface 24b of suspension member attachment part (first attachment part)
24c Mounting part (second mounting part)
26 Stiffening part 26a Lower surface 26b of stiffening part Upper surface of stiffening part

Claims (7)

A pair of left and right front side members arranged in the longitudinal direction of the vehicle;
A substantially rectangular frame-shaped suspension member attached to the lower part of the pair of front side members;
A pair of tunnel members that are disposed along the vehicle body longitudinal direction inside the front side member and that form a closed cross-section with a floor panel connected to the dash panel of the vehicle body;
A bracket connecting the front part of the tunnel member and the rear part of the suspension member;
A lower body structure of a vehicle equipped with
A mounting portion between the suspension member and the front side member is a pair of first mounting portions for mounting the bracket to the suspension member at a position where an extension line of the tunnel member and the suspension member intersect with each other,
A pair of second attachment portions for attaching the suspension member to the lower surface of the front side member;
And a lower body structure of a vehicle, wherein the first mounting portion and the second mounting portion are spaced apart from each other in the vehicle width direction.   2. The vehicle according to claim 1, wherein the bracket has a front part rising from a front side, and the front part of the bracket is connected to a front part rising from the front side of the dash panel in substantially the same plane. Lower body structure.   The bracket has a vehicle inner vertical wall portion that is inclined inward and upward in the vehicle width direction, and the dash panel has a tunnel vertical wall portion that is inclined outward and downward in the vehicle width direction. The vehicle lower body structure according to claim 1 or 2, wherein a wall portion is connected to the tunnel vertical wall portion in the same plane.   The suspension member has a pair of side member portions extending from the front cross portion on the front side extending in the vehicle width direction to the rear of the vehicle body, and a rear cross portion extending in the vehicle width direction is integrated with the rear portion of the side member portion. The lower body structure of a vehicle according to claim 1, wherein   The lower body structure of a vehicle according to claim 1, wherein the tunnel member and the bracket are integrated.   The suspension member has a stiffening portion between the side member portion and the rear cross portion, respectively, and the cross-section of the stiffening portion increases as it approaches the rear cross portion. The lower body structure of the vehicle described in 1.   The stiffening portion connects the lower surface of the stiffening portion in substantially the same plane as the lower surface of the side member portion of the suspension member, and a cross section of the stiffening portion as the upper surface of the stiffening portion approaches the rear cross portion. The lower body structure of the vehicle according to claim 6, wherein:

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