JP3344156B2 - Sub-frame mounting structure for vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an arrangement portion of a subframe for supporting a suspension device.

[0002]

2. Description of the Related Art FIGS. 7 and 8 show, for example, such conventional devices. In the figure, reference numeral 1 denotes a pair of front side members (one is omitted) disposed on both sides of the engine room E along the vehicle front-rear direction, and a rear portion 1a of the front side member 1 is curved toward the outside of the vehicle. The rear end 1b of the rear portion 1a is connected to the side sill 2.

[0003] These front side members 1,
1, a sub-frame 3 whose both ends are bifurcated is provided. That is, in the sub-frame 3, the front end 3 a and the rear end 3 b that are bifurcated are attached to the front side member 1. This rear end 3
As shown in FIG. 8, b is attached to the bottom surface 1 c of the front side member 1 having a hat-shaped cross section with bolts 4 and nuts 5. A curved portion 3c is formed in the rear end 3b of the sub-frame 3 in the vicinity of the mounting portion so as to be curved upward in a substantially semicircular shape.
A circular rubber member 7 into which one end 6a of the transverse link 6 is inserted is fitted therein, and this rubber member 7 is supported by a holding plate 8 fixed to the sub-frame 3 by bolts 9. The transverse link 6 can swing freely by the rubber member 7. Reference numeral 10 denotes a center member connected to a first cross member (not shown).

[0004] In the event of a frontal collision of the vehicle, the front side member 1 is moved from the engine (not shown) via the sub-frame 3.
Is input to the side sill 2 and the like, and the collision energy is absorbed.

[0005] Examples of this type include those described in Japanese Utility Model Laid-Open No. Hei 4-22374 or Japanese Patent Laid-Open Publication No. Hei 3-21568.

[0006]

However, in such a conventional device, the thickness of the sub-frame 3 is increased in order to ensure the rigidity of the support of the transverse link 6 and the like. As shown in (1), the sub-frame 3 is attached to the bottom surface 1c of the front side member 1 and has a curved portion 3c bulging upward in the vicinity of the attachment portion. For this reason, the cross-sectional area of the front side member 1 could not be increased in this portion, and the strength could not be improved so much.

When the front side member 1 is extended toward the rear of the vehicle and straightened as shown by a two-dot chain line in FIG. 7, the rear end portion 3b is curved as in this conventional example. If the cross-sectional areas are the same, the strength is improved. However, in this conventional example, since the cross-sectional area becomes extremely small at the mounting portion of the sub-frame 3, the rear portion 1a of the front side member 1 is curved toward the side sill 2, so that the front side member No. 1 is disadvantageous in improving the strength.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vehicle sub-frame arranging structure capable of increasing the cross-sectional area of the front side member and improving the strength by making the front side member straight.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and the invention described in claim 1 is provided with a pair of front side members on both sides of an engine room along a vehicle longitudinal direction. A vehicle subframe disposing portion structure in which the front side members are joined to a lower surface portion of a dash panel, and a subframe is disposed between the front side members on the engine room side of the dash panel. A suspension mount member is disposed below the dash panel by attaching the suspension mount member to the dash panel and the front side member. To the compression rod bracket And one end of the transverse link is inserted and fitted through a resilient member into the space formed by the front side member and the suspension mount member. The present invention is characterized in that the vehicle sub-frame is provided along the vehicle longitudinal direction.

[0010]

According to the first aspect of the invention, at the time of a frontal collision of the vehicle, an impact load is input from the engine to the subframe. Then, this load is input to the suspension mount member and transmitted to the dash panel and the front side member. At the same time, the power is transmitted to the front side member via the compression rod bracket. Of course, the front side member also has an impact load directly input from its front end.

In this case, the front side member also extends rearward from the sub-frame disposition portion in the vehicle front-rear direction, so that the front side member does not curve to the side sill side as in the related art, but acts in the direction of the impact load. Are arranged on a straight line. In addition, since the thick subframe is not directly fixed to the front side member, it is not necessary to consider the thickness of the subframe, and the cross sectional area of the front side member can be secured. Furthermore, since the end of the transverse link is inserted and fitted via an elastic member into the space formed by the compression rod bracket, the front side member and the suspension mount member, the vicinity of the front side member is different from the conventional case. In this case, since it is not necessary to form a curved portion for supporting the transverse link in the subframe, the cross-sectional area of the front side member can be enlarged also in this regard.
Therefore, the strength of the front side member can be improved because the front side member can be made linear and the cross-sectional area can be ensured even at the subframe mounting portion.

Further, by providing the suspension mount member, the load from the sub-frame can be dispersed and transmitted to the dash panel and the front side member via this member, so that the impact energy absorbing characteristics can be improved.

Of course, the subframe is not directly fixed to the front side member, but the rear end of the subframe is
Attachment to the suspension mount member and attachment to the front side member with the compression rod bracket interposed result in securing the support strength of the sub-frame.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 6 show an embodiment of the present invention.

First, the structure will be described. In the figure, reference numeral 11 denotes a pair (one is omitted) of front side members arranged on both sides of an engine room E along the longitudinal direction of the vehicle. It extends rearward from the room E side, is joined to the lower surface side of the dash panel 13, and also extends rearward along the vehicle front-rear direction from a portion where the subframe 15 is provided, which will be described later. It extends straight down to the bottom. A connecting member 12 is provided in the middle of the front side member 11 and extends toward the outside of the vehicle along the vehicle width direction and is connected to a side sill (not shown) (see FIG. 1 or 2).

On the engine room E side near the dash panel 13, there is provided a sub-frame 15 whose both ends are substantially bifurcated along the vehicle width direction.

More specifically, below the dash panel 13,
Inside each of the front side members 11, a pair of suspension mount members 16 as shown in FIG. 3 (one is omitted), and a bolt plate 17 as shown in FIG. ing.

This suspension mount member 16
As shown in FIGS. 1 and 3, the upper side 16a and the lower side 16b are joined to the back side of the dash panel 13, and the vehicle outer side 16c is formed of the front side member 11 as shown in FIG. It is welded to a stepped surface portion 11b along the substantially horizontal direction, which is one step higher than the bottom surface portion 11a, and furthermore, a vehicle inner side portion 16d as shown in FIGS. Welded inside.

The bolt plate 17 has a bulge 17a projecting upward at a substantially central portion thereof.
b is welded to the upper surface of the suspension mount member 16, and the vertical wall 17c is welded to the vertical surface 11c of the front side member (see FIG. 5).

The rear end 15a of the sub-frame 15
However, as shown in FIG.
It is attached by welding to 0. This bolt 20
The shaft 20a is inserted into the hole 16e of the suspension mount member 16, and the head 20b is
Is fitted to the bulging portion 17a.

In the vicinity of the bolt 20 mounting portion, as shown in FIG.
“a” is attached to the bottom surface 11 a of the front side member 11 via a compression rod bracket 22. That is, the compression rod bracket 22 has one end 22a having the bolt 23 and the nut 2
4, fixed to the rear end 15a of the sub-frame 15,
The other end 22b is fixed to the front side member bottom surface 11a by bolts 25 and nuts 26. Of course, the three members such as the rear end 15a of the sub-frame 15, the one end 22a of the compression rod bracket 22, and the suspension mount member 16 can be fastened together.

A space 27 is formed by the compression bracket 22, the front side member 11, and the suspension mount member 16, and one end 29 of the transverse link 29 is formed in the space 27.
The circular rubber member 30 into which a is inserted is inserted and fitted. The rubber member 30 allows the transverse link 2
9 is swingable. In this state, a line P connecting both attachment points of the compression bracket 22 is close to the center O of the one end 29 a of the transverse link 29.

Next, the operation will be described.

First, at the time of a vehicle front collision, an impact load is input to the sub-frame 15 from an engine (not shown).
Then, this load is input to the suspension mount member 16 via the bolt 20 and the dash panel 13
And transmitted to the front side member 11. At the same time, the power is transmitted to the front side member 11 via the compression rod bracket 22. And then,
The power is transmitted to a side sill (not shown) via the connecting member 12. Of course, the front side member also has an impact load directly input from its front end.

In this case, the front side member 11
The rear is also extended along the vehicle front-rear direction from the sub-frame 15 arrangement portion, so that the sub-frame 15 is not curved to the side sill side as in the related art, but is arranged in a straight line with respect to the direction of the impact load. I have. In addition, the thick sub-frame 15
Is not directly fixed to the front side member 11, it is not necessary to consider the thickness of the sub-frame 15, and the cross-sectional area of the front side member 11 can be secured. Further, one end 29a of the transverse link 29
Is inserted and fitted via the rubber member 30 into the space 27 formed by the compression rod bracket 22, the front side member 11 and the suspension mount member 16, so that in the vicinity of the front side member 11 as in the related art, Since it is not necessary to form a curved portion for supporting the transverse link 29 on the sub-frame 15, the cross-sectional area of the front side member 11 can be enlarged also in this regard. Therefore, the strength of the front side member 11 can be improved because the front side member 11 can be made linear and the cross-sectional area can be ensured even at the sub-frame 15 attachment portion.

The suspension mount member 16
, The load from the sub-frame 15 is
Since the power can be dispersed and transmitted to the dash panel 13 and the front side member 11 via the member 16, the impact energy absorption characteristics can be improved.

Further, as shown in FIG. 5, the front side member 1 is formed by the outer side 16c of the suspension mount member 16 and the vertical wall 17c of the bolt plate 17.
When the load is input to the front side member 11 from the sub-frame 15 via the suspension mount member 16 and the bolt plate 17, since the former is performed along the horizontal direction and the latter is performed along the vertical direction. , For the input in the vehicle left-right direction, the outer side portion 16c
Since the joint portion receives in the shear direction, and the vertical wall portion 17c receives the shear direction in response to the input in the vehicle vertical direction, the front side member 11 is effectively applied to the load in any direction. Load can be transmitted.

Further, as shown in FIG. 6, a line P connecting both mounting points of the compression bracket 22 is close to the center O of the one end 29a of the transverse link 29. This is advantageous in terms of the strength of the compression bracket 22 against a load.

Of course, although the sub-frame 15 is not directly fixed to the front side member 11, the sub-frame 15
The rear end 15a of the suspension mount member 16
To the compression rod bracket 22
Therefore, the support strength of the sub-frame 15 can be ensured because it is attached to the front side member 11 at two locations.

[0031]

As described above, according to the first aspect of the present invention, it is possible to increase the cross-sectional area of the portion where the front side member is provided with the subframe, and to align the front side member with a straight line. Can be installed in
The strength of the front side member can be improved, and the provision of the suspension mount member allows the load from the subframe to be dispersed and transmitted to the dash panel and the front side member via this member. Practically useful effect that energy absorption characteristics can be improved.

[Brief description of the drawings]

FIG. 1 is a plan view of a main part showing an embodiment of the present invention.

FIG. 2 is a perspective view of the main part showing the same embodiment.

FIG. 3 is a perspective view of a suspension mount member showing the same embodiment.

FIG. 4 is a perspective view of a bolt plate showing the same embodiment.

FIG. 5 is a cross-sectional view of the same embodiment, taken along line AA of FIG. 1;

FIG. 6 is a cross-sectional view taken along the line BB of FIG. 1 showing the same embodiment.

FIG. 7 is a schematic plan view showing a conventional example.

8 is a cross-sectional view of the conventional example taken along line CC of FIG. 7;

[Explanation of symbols]

 11 Front side member 13 Dash panel 15 Subframe 16 Suspension mount member 22 Compression rod bracket 27 Space 29 Transverse link 29a One end 30 Rubber member (elastic member) E Engine room K Cabin

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B62D 21/00 B62D 25/20

Claims (1)

(57) [Claims] 1. A pair of front side members are disposed on both sides of an engine room along a vehicle front-rear direction, and both front side members are joined to a lower surface of a dash panel. In a vehicle subframe disposing portion structure in which a subframe is disposed between both front side members, a suspension mount member is disposed below the dash panel by attaching the suspension mount member to the dash panel and the front side member. The subframe is attached to the suspension mount member, and is attached to the front side member via a compression rod bracket. The subframe is attached to a space formed by the compression rod bracket, the front side member, and the suspension mount member. A vehicle characterized in that one end of a transverse link is inserted and fitted via an elastic member, and the front side member also extends rearward from a subframe arrangement site in the vehicle front-rear direction. Sub-frame installation part structure.