JP2001063617A - Suspension frame structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve rigidity of a support part of a suspension lower arm and improve braking force during braking and cornering. SOLUTION: This frame structure is provided with an upper plate 7, a lower plate, pairs of supports parts 9 of a suspension lower arm provided on both right and left end parts of the upper plate 7 and the lower plate, and lower arm mounting brackets 11 arranged on the support parts 9 of the suspension lower arm on the front side of the upper plate 7 and the lower plate. In such a case, the support parts 9 of the suspension lower arm on the front side of the lower plate is extended and flange parts 13a of the lower arm mounting brackets 11 are sandwiched between the upper plate 7 and extended parts 8a of the lower plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a vehicle suspension frame structure for supporting a suspension lower arm and the like.

[0002]

2. Description of the Related Art In general, the body structure of an automobile is roughly classified into a structure with a frame used for trucks and the like and a frameless structure used for passenger cars and the like. Instead of having a frame, the frameless structure incorporates side members and cross members as part of the body to improve torsional rigidity. Chassis components are attached directly to the body, but some vehicles are attached to a partial frame, or so-called subframe, before being assembled to the body.

[0003] This sub-frame is usually called a suspension frame because a suspension lower arm is attached to both sides. Hereinafter, the subframes and the like are collectively referred to as a suspension frame. This suspension frame is a suspension lower arm,
Stabilizers etc. are attached and assembled to the vehicle body. This suspension frame generally has an upper plate, a lower plate, and a lower arm mounting bracket as a basic structure.

FIGS. 11 to 13 show the structure of a conventional suspension frame (JP-A-7-179180). The suspension frame 100
Both sides are supported by a pair of side members 101, 101, and suspension lower arms 102, 102 are attached to both sides of the suspension frame 100. A center member 104 is bridged between the suspension frame 100 and a cross member 103 provided at the front, and an engine 105 is assembled. The suspension frame 100 is normally disposed below an engine room partitioned by a dash panel 106, and is equipped with various equipment and the like. A steering knuckle 107 is attached to the dash panel 106 by a bracket 108.

As shown in FIGS. 14 to 16, the suspension frame 100 is generally formed by joining an upper plate 109 and a lower plate 110, which are formed by press-forming a steel plate or the like, by welding or the like. A pair of suspension lower arm mounting portions 100a and 100b are provided on both sides in the vehicle width direction. Since a load during braking is applied to the suspension lower arm mounting portion 100a on the front side of the vehicle body, the lower arm mounting bracket 1
11 are provided. The lower arm mounting bracket 111 is formed by opening one side surface of a substantially square box shape by press molding or the like.
a, 111b are suspension lower arms 102, 10
Two shaft supports 112, 112 are provided.

Conventionally, a suspension lower arm 102,
Since a load is applied to the shaft support portions 112 of the lower arm mounting bracket 111, the mounting portion of the lower arm
6. As shown in FIG.
9a is partially overlapped and joined to the upper surface of the lower arm mounting bracket 111. Further, since the distal end of the lower plate 110 is welded to the wall surface of the lower arm mounting bracket 111, the reinforcement 113 is reinforced across the upper plate 109 and the lower plate 110. Further, a flange portion 114 is provided along an opening end of the lower arm mounting bracket 111 to improve rigidity.

[0007] The most severe condition of the suspension frame 100 is when a load in the front-rear direction is applied (for an actual vehicle, for example, when braking or falling into a pothole). As shown in FIG. 17, the deformation mode of the suspension frame 100 at the time of the braking load is as follows.
The mounting portion 11 is in a mode of being opened while being twisted outward, and the central portion of the suspension frame 100 is in a mode of sinking downward. On the other hand, the stress concentration portion F during braking is around the lower arm mounting bracket 111.

[0008]

For the suspension frame 100, the steering stability is improved by increasing the rigidity around the suspension lower arm mounting portion. To increase the rigidity of the cross section of this part, the suspension frame 100
When the section of the lower arm mounting bracket 111 is thickened,
And the weight is greatly increased. Since the stress concentration portion during braking is around the lower arm mounting bracket 111, it is desirable to improve the rigidity of this portion. It is considered that the cause of the stress concentration is that the end of the lower plate 110 and the flange portion R of the upper plate 109 are located at the same position.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide a suspension frame structure of an automobile capable of improving rigidity of a support portion of a suspension lower arm and improving braking force at the time of braking and cornering.

[0010]

According to the present invention, in order to solve the above-mentioned problems, an upper plate and a lower plate which are vertically overlapped, and a suspension lower arm support portion is provided on both left and right ends of the upper plate and the lower plate. In a suspension frame structure of an automobile, in which a lower arm mounting bracket is provided on a support portion of a suspension lower arm on the front side of the upper plate and the lower plate, a support portion of the suspension lower arm on the front side of the lower plate is extended,
That is, the flange of the lower arm mounting bracket is sandwiched between the extension of the lower plate and the upper plate. Also, the present invention provides an extension of the lower plate,
The lower arm mounting bracket is extended and joined along the lower surface side flange portion so as to hold the lower arm mounting bracket. Further, in the present invention, a bead portion is provided on the upper plate so as to straddle a butt portion between the lower plate and the lower arm mounting bracket.

[0011]

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

FIG. 1 shows a front part of a vehicle body of an automobile. In an engine room 2 partitioned by a dash panel 1, side members 3, 3 arranged on both side parts of the vehicle body are connected via brackets 4. The suspension frame 5 is provided on the lower side of the engine room. Struts 6 and 6 for suspending wheels are provided outside the side members 3 and 3, respectively. The structure of the suspension frame 5 will be described with reference to FIGS. The suspension frame 5
The upper plate 7 and the lower plate 8 are formed by press molding, and the upper plate 7 and the lower plate 8 are formed by welding or the like.
On both sides of the suspension frame 5 in the vehicle width direction,
Support portions 9 and 10 for suspension lower arm (not shown)
Are provided in the front-rear direction of the vehicle body, respectively. A support portion 9 of the suspension lower arm on the front side of the suspension frame 5 is provided with a lower arm mounting bracket 11 supported by the upper plate 7 and the lower plate 8.

The lower arm mounting bracket 11 is formed by pressing one side of a substantially rectangular box shape by press molding or the like. The suspension lower arm swings on front and rear wall surfaces 11a and 11b opposed to the front and rear direction of the vehicle body. Mounting holes 12 for mounting the shaft are provided (see FIG. 8). The lower arm mounting bracket 11 is
It is supported from the 1b side by the support portions 7a, 8a of the upper plate 7 and the lower plate 8. The support portion 7a of the upper plate 7 is a lower arm mounting bracket 1.
1 and an inner side surface 11d in the width direction of the vehicle body.
Is joined to the lower end of the rear wall surface 11b of the lower arm mounting bracket 11.

The lower arm mounting bracket 11 includes:
As shown in FIG. 4 to FIG.
1d and flange portions 13a and 13b are provided along the opening edge of the front wall surface 11a, and the width H of the flange portion 13a at the portion where the flange portion 7b of the support portion 7a of the upper plate 7 overlaps is formed to be large. In accordance with this, the width H 'of the flange portion 7b of the upper plate 7 is formed large. Thereby, the radius R of the support portion of the lower arm mounting bracket 11 is increased as compared with the related art. On the other hand, the lower plate 8 is formed by extending the flange portion 8a to a portion corresponding to the flange portion 13a, and the extended flange portion 8b is formed by the flange portion 7b of the upper plate 7.
At the same time, they are joined by spot welding so as to sandwich the flange portion 13a (see FIGS. 7 and 9). At this time, since the conventional rear side wall surface 11b extends below the flange portion 13a, the lower wall portion of the flange portion 13a is omitted to facilitate extension of the extension flange portion 8b.

Next, according to the above configuration, the lower plate 8
An extension flange portion 8b is formed by extending the flange portion 8a. The extension flange portion 8b is disposed on the lower surface of the flange portion 13a of the lower arm mounting bracket 11, and the flange portion on the support portion 7a side of the upper plate 7 is formed. 7b is arranged on the upper surface of the flange 13a. The extension 13a of the lower plate 8 and the flange 7a of the upper plate 7 are joined by spot welding or the like so as to sandwich the flange 13a. In this manner, the lower arm mounting bracket 11 clamps the flange portion 13a between the extending flange portion 8b of the lower plate 8 and the flange portion 7a of the upper plate 7, so that the rigidity at the time of braking is improved by 30% and the strength is improved as compared with the conventional art. Can be achieved. The rigidity at the time of lateral force (at the time of cornering) as well as the rigidity at the time of braking can be improved by 30% compared with the conventional art. Further, since the width H 'of the flange portion 7b of the upper plate 7 is made large, the curvature of the curved portion of the support portion 7a of the upper plate 7 can be increased, so that the stress at this portion is reduced by 70% compared with the conventional case. In addition, the strength can be improved.

Next, FIG. 10 shows another embodiment of the present invention, in which the same parts as those in FIG. In this case, the extension flange portion 8b of the lower plate 8 extends to the front side of the lower arm mounting bracket 11, and the extension portion 8c extends to the front flange portion 13b of the lower arm mounting bracket 11. In this way, the extension 8c is spot-welded to the flange 13b, so that the extension 8c is wound around the lower arm mounting bracket 11 so that the rigidity can be further improved. In addition, a bead 14 is provided on the support portion 7a of the upper plate 7 at a position where the lower arm mounting bracket 11 and the lower plate 8 straddle.
By forming, it is possible to prevent this portion from being broken and improve the rigidity. The number and length of the beads 14 can be set arbitrarily.

The present invention is limited to the above embodiment only.
For example, the width and the length of the extending flange portion 8b of the lower plate 8 may be set as necessary, and the flange portion 7 of the upper plate 7 may be set.
The width and length of b can be appropriately set according to the lower plate 8.

[0018]

As described above, according to the vehicle suspension frame structure of the present invention, the following effects can be obtained. 2. A suspension according to claim 1, wherein a pair of upper and lower plates are vertically overlapped, and a pair of suspension lower arm support portions are provided at both left and right ends of the upper and lower plates, respectively, and a front suspension of the upper and lower plates is provided. In a vehicle suspension frame structure in which a lower arm mounting bracket is provided on a lower arm supporting portion, a supporting portion of a suspension lower arm in front of the lower plate is extended, and a lower arm mounting bracket is provided between the extended portion of the lower plate and the upper plate. , The rigidity and strength can be improved without increasing the weight due to the enlargement of the lower arm mounting bracket. Since the rigidity during braking and lateral force can be improved, steering stability can be improved. In addition, since the current product can be completed with the minimum mold modification, it is excellent in economy. Claim 2
In this case, the extension of the lower plate is extended and joined along the lower surface side flange of the lower arm mounting bracket so as to hold the lower arm mounting bracket, so that rigidity can be improved. In claim 3, since a bead portion is provided on the upper plate so as to straddle the butted portion of the lower plate and the lower arm mounting bracket, it is possible to prevent this portion from being broken.

[Brief description of the drawings]

FIG. 1 is a conceptual perspective view showing an embodiment of a vehicle suspension frame structure according to the present invention.

FIG. 2 is a plan view showing the suspension frame structure of FIG.

FIG. 3 is an exploded perspective view showing the suspension frame structure of FIG. 2;

FIG. 4 is a plan view showing a lower arm mounting bracket mounting portion of FIG. 2;

FIG. 5 is a plan view showing the upper plate of FIG. 4 with the upper plate removed;

FIG. 6 is a plan view showing the lower arm mounting bracket of FIG. 5 with the bracket removed;

FIG. 7 is a sectional view taken along line AA of FIG. 4;

FIG. 8 is a sectional view taken along line BB of FIG. 4;

FIG. 9 is a sectional view taken along line CC of FIG. 4;

FIG. 10 is a plan view showing a suspension frame structure according to another embodiment of the present invention.

FIG. 11 is an exploded perspective view showing a conventional suspension frame structure.

FIG. 12 is a plan view showing a conventional suspension frame structure.

FIG. 13 is a side view of FIG.

FIG. 14 is a plan view showing a conventional suspension frame structure.

FIG. 15 is a perspective view showing a conventional suspension frame structure.

FIG. 16 is a sectional view taken along line DD of FIG. 14;

FIG. 17 is a perspective view showing a deformation mode at the time of a braking load by the conventional suspension frame structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Dash panel 2 Engine room 3 Side member 4 Bracket 5 Suspension frame 6 Strut 7 Upper plate 8 Lower plate 9, 10 Suspension lower arm support part 11 Lower arm mounting bracket 12 Mounting holes 13a, 13b Flange part 7a Upper plate support part 7b Upper Flange portion of plate support portion 8a Lower plate support portion 8b Extension flange portion

Claims (3)

[Claims] An upper plate and a lower plate superimposed on each other and a pair of support portions for suspension lower arms are provided at both left and right end portions of the upper plate and the lower plate, respectively, and a front suspension of the upper plate and the lower plate is provided. In a vehicle suspension frame structure in which a lower arm mounting bracket is provided on a lower arm supporting portion, a supporting portion of a suspension lower arm in front of the lower plate is extended, and a lower arm mounting bracket is provided between the extended portion of the lower plate and the upper plate. A suspension frame structure for an automobile, characterized in that the flange portion is sandwiched. 2. The vehicle according to claim 1, wherein the extension of the lower plate is extended and joined along the lower surface side flange of the lower arm mounting bracket so as to hold the lower arm mounting bracket. Suspension frame structure. 3. The vehicle suspension frame structure according to claim 1, wherein a bead portion is provided on the upper plate so as to straddle a butt portion between the lower plate and the lower arm mounting bracket.