JPH10181326A - Torsion beam type suspension - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent excess stress from concentrating in a connected portion with a twist beam and a trailing arm while allowing the twist beam functioning as the torsion beam effectively. SOLUTION: A twist beam 12 is formed with three pipe shaped beams 28-32. End parts 28A-32A of respective beams 28-32 are rigidly coupled with both end parts 14A, 14B of a trailing arm 14 by welding with them being penetrated into both the end parts of the trailing arm. Accordingly, excess stress may be prevented from concentrating at a coupled portion with the trailing arm 14 than a case of open cross sectional twist beam while allowing function as the torsion beam become agreeably effective.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torsion beam arranged longitudinally in a vehicle width direction, and rigidly connected to both longitudinal ends of the torsion beam and arranged substantially longitudinally in the longitudinal direction of the vehicle. The present invention relates to a torsion beam type suspension including a pair of trailing arms.

[0002]

2. Description of the Related Art Conventionally, a torsion beam type suspension (for example, an intermediate beam type suspension) has been used as a rear suspension for a small car or the like. An example of this type of torsion beam type suspension is disclosed in Japanese Patent Application Laid-Open No. 58-20505, and the configuration disclosed in this publication will be briefly described below.

As shown in FIG. 6, a torsion beam type rear suspension 100 has a torsion beam 102 arranged longitudinally in the vehicle width direction, and is coupled to both ends of the torsion beam 102 via brackets 104 in a substantially vehicle front-rear direction. And a pair of trailing arms 106 arranged in the longitudinal direction.

A bush 108 is provided at the front end of the trailing arm 106,
Numeral 6 is resiliently supported on the vehicle body via the bushing 108 so as to be swingable in the vertical direction of the vehicle. Further, a spindle 110 is disposed on the rear end side of the trailing arm 106, and a rear wheel 112 is rotatably supported by the spindle 110.

The above-mentioned left and right trailing arms 106
Are formed by pressing a plate into a U-shaped open cross section. The reason why the torsion beam 102 is formed to have an open cross-sectional shape is to allow the torsion beam 102 to function as a torsion bar when the right and left rear wheels 112 are displaced in opposite phases.

However, when the above-mentioned torsion beam type rear suspension 100 is employed, the left and right rear wheels 112 are displaced in opposite phases because the torsion beam 102 is formed in an open cross-sectional shape.
When the torsion beam is twisted, distortion (warping) occurs due to the torsion beam 102 being twisted at a joint (an arrow A section) between the end of the torsion beam 102 and the trailing arm 106. Note that "warping" means that when a member P (corresponding to the torsion beam 102) having an open cross-sectional shape as shown in FIG. 7A is torsionally deformed, as shown in FIG. Are relatively displaced in the longitudinal direction.
This means that a strain Q is generated at both ends in the longitudinal direction. For this reason, in the case of the above-described configuration, there is a problem that a relatively large stress (shear stress τ) is concentrated at the joint between the end of the torsion beam 102 and the trailing arm 106.

The present invention has been made in consideration of the above-described facts, and a torsion beam type in which an excessive stress is prevented from being concentrated on a joint portion between a torsion beam and a trailing arm while allowing the torsion beam to effectively function as a torsion beam. The purpose is to get a suspension.

[0008]

According to a first aspect of the present invention, there is provided a torsion beam disposed longitudinally in a vehicle width direction, and rigidly coupled to both longitudinal ends of the torsion beam and substantially in the longitudinal direction of the vehicle. And a pair of trailing arms arranged as a longitudinal direction, and a torsion beam type suspension comprising:
The torsion beam is formed by a plurality of hollow or solid rod members.

According to a second aspect of the present invention, in the first aspect of the present invention, the trailing arm has a pair of opposed portions facing each other in the vehicle width direction, and an end of each of the rod-shaped members is attached to the tray. The end portion of the rod-shaped member and the two opposing portions are rigidly connected to each other while penetrating both opposing portions of the ring arm.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a part of the plurality of rod-shaped members is offset from the remaining rod-shaped members substantially toward the front of the vehicle. It is characterized by that.

According to the first aspect of the present invention, the torsion beam is not constituted by a beam having an open section, but is constituted by a plurality of rod-like members each having a hollow or solid shape. Here, the beam of the hollow or solid rod-shaped member is higher in torsional rigidity than the beam of the open section,
Also, it is twisted uniformly. As a result, even if the left and right wheels are displaced in opposite phases and the torsion beam is deformed (twisted), warping does not occur at the joint between the torsion beam and the trailing arm.

Further, in the present invention, since the torsion beam is constituted by a plurality of rod members, not only the function as the torsion beam originally required for the torsion beam is ensured, but also the arrangement of the rod members is appropriately selected. The function as a torsion beam can be exhibited well.

According to the second aspect of the present invention, the trailing arm having a pair of opposed portions facing each other in the vehicle width direction has the ends of each rod-shaped member penetrated through the both opposed portions. Since the end of the rod-shaped member and the opposing portions thereof are rigidly connected, each rod-shaped member and the trailing arm are connected at a plurality of positions (two positions). Therefore, as compared with the case where the rod-shaped member and the trailing arm are joined at one place, the support span becomes longer because the rod-like member and the trailing arm are joined at a plurality of places at a distance, and the trailing arm in the vehicle width direction vertical plane Is increased.

According to the third aspect of the present invention, since a part of the plurality of bar-shaped members is arranged so as to be substantially offset toward the front side of the vehicle with respect to the remaining bar-shaped members, the offset amount between the plurality of bar-shaped members is reduced. Compared to the case where there is almost no restraint, the constraint on the trailing arm in the vehicle horizontal plane is increased.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] The first embodiment will be described below with reference to FIGS. The first embodiment corresponds to one embodiment of the present invention described in claims 1 and 2.

As shown in FIG. 1, a torsion beam type suspension 10 has a torsion beam 12 arranged longitudinally in the vehicle width direction, and a longitudinal direction substantially in the vehicle longitudinal direction at both ends of the torsion beam 12 in the longitudinal direction. A pair of trailing arms 14,
It is comprised including.

Each trailing arm 14 is formed by bending a pipe-like member into a crank shape at an intermediate portion in the longitudinal direction. At the front end of the trailing arm 14, a bush 16 whose axial direction is in the vehicle width direction is attached. Through this bush 16, the trailing arm 14 is swingably and elastically supported on the vehicle body side. Have been. Further, a carrier bracket 18 having a substantially U shape in plan view is fixed to the rear end of the trailing arm 14 by welding. A spindle (not shown) that rotatably supports the rear wheel 20 is attached to the outside of the carrier bracket 18. An absorber bracket 22 is fixed by welding near the rear end of the trailing arm 14, and a shock absorber 26 around which a coil spring 24 is coaxially wound is attached to the absorber bracket 22.

Here, in the present embodiment, the above-mentioned torsion beam 12 is formed by three beams 2 as rod members.
8, 30, and 32. Beam 28
Is a pipe-shaped member having a straight and circular cross section.
Further, as shown in FIG. 2, both sides 14A and 14B of the trailing arm 14 having a substantially elliptical cross section (the both sides 1A and 14B).
4A and 14B correspond to "a pair of opposed portions facing each other in the vehicle width direction" in the invention of claim 2, and a coaxial insertion hole 34 is formed. Then, the longitudinal end 28A of the beam 28 penetrates into the insertion hole 34 of both sides 14A, 14B of the trailing arm 14, and in this state, the end 28A and each side 14A of the trailing arm 14, 14B are fixed by welding. Therefore, the connecting portion (the portion viewed in the direction of the arrow B) of the end 28A of the beam 28 in the longitudinal direction and the trailing arm 14 is two places inside and outside. Note that the above-described configuration is equivalent to the beam 3
Since the same applies to 0 and 32, description of the configuration of each beam 30 and 32 will be omitted by assigning the same reference numerals.

Returning again to FIG. 1, the distance X between the rearmost beam 28 and the frontmost beam 32, the uppermost beam 30 and the lowermost beam The distance Y to the trailing arms 28 and 32 is set to a predetermined distance from the viewpoint of securing rigidity with respect to the trailing arm 14.

The operation and effect of this embodiment will be described below. First, in the present embodiment, since the torsion beam 12 is constituted by the plurality of hollow pipe-shaped beams 28, 30, and 32, the torsion beam 12
, Each beam 28, 30, 32 has a closed cross section,
Therefore, each twisting method becomes uniform. As a result, even if the right and left rear wheels 20 are displaced in opposite phases and the torsion beam 12 is deformed (twisted), warping does not occur at the joint between the torsion beam 12 and the trailing arm 14. As described above, according to the present embodiment, it is possible to prevent excessive stress from concentrating on the joint (the portion indicated by the arrow B in FIG. 4) between the torsion beam 12 and the trailing arm 14. In addition, the life for fatigue due to aging is prolonged.

Second, according to the present embodiment, as described above, the torsion beam 12 is divided into a plurality of pipe-shaped beams 2.
With the configuration including 8, 30, and 32, the function as the torsion beam originally required of the torsion beam 12 can be secured. In other words, for example, when a torsion beam is configured using only the pipe-shaped beam 28, if the required rigidity as a suspension is secured, the outer diameter of the beam 28 increases, and the torsional rigidity becomes too high. It cannot serve as a torsion beam. However, the plurality of pipe-shaped beams 28, 30, 32 causes the torsion beam 1
By configuring 2, the outer diameter of each can be reduced, and the torsional rigidity (of the torsion beam as a whole) can be appropriately reduced. Further, by setting the outer diameter to an appropriate size, the function as a torsion beam can be fulfilled according to the vehicle.

The first and second operations and effects described above (the torsion beam 12 which is rigidly connected to the pair of trailing arms 14 and connects the two to each other is constituted by a plurality of pipe-shaped beams 28, 30 and 32). The basic operation and effect of the present invention correspond to the operation and effect of the present invention.

Third, in the present embodiment, the trailing arm 14 is formed of a pipe-shaped member having a substantially elliptical cross section to provide a pair of opposite side portions 14A and 14B. , 14B each beam 2
8, 30, 32 longitudinal ends 28A, 30A, 32
A with the end portions 28A, 30
A, 32A and the respective side portions 14A, 14B are rigidly connected by welding, so that the longitudinal ends 28A, 30A, 32A of the beams 28, 30, 32 are connected to the trailing arm 14 and a plurality of positions (each It is joined at two places (the part viewed from the arrow B line). Therefore, for example, the support span is smaller than when the longitudinal ends 28A, 30A, 32A of the beams 28, 30, 32 are penetrated only through the inner side 14A of the trailing arm 14 and rigidly connected. Since the length is longer, the support rigidity is higher (in other words, it can be said that the change is from cantilever support to double support). Therefore, the restraint on the trailing arm 14 in the vertical plane in the vehicle width direction increases.

As a result, according to the present embodiment, the rigidity of the trailing arm 14 with respect to the camber angle can be ensured. In other words, when the configuration as in the above example is employed, the restraint on the trailing arm 14 is reduced, so the rigidity of the trailing arm 14 with respect to the camber angle is insufficient, and the camber angle may deviate from the set angle. However, according to the present embodiment, as described above, the trailing arm 14 is highly constrained, so that the camber angle does not deviate from the set angle.

It should be noted that the above-described third operation and effect (each beam 2A on both sides 14A and 14B of the trailing arm 14)
8, 30 and 32 are penetrated and then rigidly connected), which corresponds to the operation and effect of the present invention.

In addition to the above, according to the present embodiment, the torsion beam 12 which is rigidly connected to the pair of trailing arms 14 and connects the two is connected to the plurality of pipe-shaped beams 2.
Due to the configuration of 8, 30, and 32, several operations and effects described below can be obtained.

First, in the present embodiment, the distance X between the rearmost beam 28 and the frontmost beam 32, the uppermost beam 30 and the lowermost beam 30 are set. Since the distance Y to 28 and 32 is set to a predetermined distance from the viewpoint of securing the rigidity to the trailing arm 14, the rigidity for the camber angle and the torsional rigidity can also be secured from this point. That is, by appropriately selecting the distance X and the distance Y described above, it is possible to prevent the camber angle from deviating from the set angle and to tune the torsional rigidity of the torsion beam 12 to an appropriate rigidity. It is to be noted that a second embodiment described below applies this function and effect from the viewpoint of the toe angle.

According to the present embodiment, the beams 28,
By appropriately selecting the longitudinal lengths of the wheels 30, 32, the wheel alignment can be arbitrarily adjusted.

Further, according to the present embodiment, the beam 2
By appropriately selecting the cross-sectional shape of the pipe-shaped members constituting the members 8, 30, and 32, the roll rigidity required for the vehicle can be increased. [Second Embodiment] Hereinafter, a second embodiment will be described with reference to FIG. This second embodiment corresponds to a third embodiment. The same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 3, in the torsion beam type suspension 40 according to the present embodiment, a trailing arm 42 having an extension 42A extending substantially in front of the vehicle from the trailing arm 14 described above. Is used. However, the arrangement position of the bush 16 is the same as that of the first embodiment. And torsion beam 4
Among the three beams 28, 30, 32 constituting the beam 4, the beam 32 disposed at the forefront is disposed between the extension portions 42 </ b> A of the trailing arm 42. Therefore, beam 32
Is disposed at a position offset from the beam 28 by a predetermined distance Z toward the front of the vehicle.

According to the above configuration, the beam 32 is
8, the tray is offset in the vehicle front side by a predetermined distance Z, so that the tray in the vehicle horizontal plane (in the plane of the arrow Z in FIG. 3) is different from the case of the first embodiment described above. The constraint on the ring arm 42 is increased. As a result, the rigidity of the trailing arm 42 with respect to the toe angle can be ensured. That is, when the present embodiment is compared with the above-described first embodiment, the beams 32, 30 are arranged by offsetting the beam 32 toward the vehicle front side.
32 and a pair of trailing arms 42 constitute a large frame in plan view. Accordingly, the restraining force on the trailing arm 42 in the horizontal plane of the vehicle is greater than in the case of the first embodiment. For this reason, according to the present embodiment, the rigidity of the trailing arm 42 with respect to the toe angle can be secured more than in the first embodiment.

In the above embodiment, the beams 28, 3
Welding is adopted as a connecting means for rigidly connecting the trailing arms 0, 32 to the trailing arms 14, 42, but the present invention is not limited thereto.
Any configuration can be applied as long as it can be rigidly connected to 4, 42.

For example, in the embodiment shown in FIG. 4, a pipe-shaped collar 50 is inserted into each of the through holes 34 on both sides 14A and 14B of the trailing arm 14 and fixed by welding. On the other hand, the beam 52 as a rod-shaped member
Is set shorter than the width dimension between the trailing arms 14, and a bolt-shaped member 54 is attached to the longitudinal end 52A. The bolt-shaped member 54 has a base 54A that is press-fitted into a longitudinal end 52A of the beam 52, and a stopper 54B that is formed adjacent to the base 54A and has a large diameter and abuts on the end 52A of the beam 52. And a small diameter portion 54C formed coaxially from the stopper 54B and inserted into the collar 50. The peripheral surface of the small-diameter portion 54C on the stopper 54B side is knurled (a configuration in which splines are fitted may be employed), and a male screw is formed on the peripheral surface of the distal end portion of the small-diameter portion 54C. ing. After the small diameter portion 54C of the bolt-shaped member 54 is inserted into the collar 50, the nut 58 is connected to the small diameter portion 54C via the washer 56.
The beam 52 is rigidly connected to the trailing arm 14. According to this configuration, the same operation and effect as in the case of welding can be obtained.

In the first embodiment, three beams 2
Although the torsion beam 12 is constituted by 8, 30, and 32, the beams 28, 30, and 32 may be connected to each other by using a vibration isolator 60 as shown in FIG. . Specifically, the vibration isolator 60 is made of an elastic material such as rubber, and has a substantially triangular shape. Further, circular cutouts 62 are formed at each corner of the vibration isolator 60, and the beams 28, 30, and 32 are fitted into these cutouts 62. In this embodiment, the vibration isolator 60 is disposed at the middle part in the longitudinal direction of the torsion beam 12 (illustrated by a solid line).
It may be disposed on both sides (shown by a two-dot chain line). According to the above configuration, the mutual beams 28, 30, and 32 are used as the vibration isolator 6
Since it is elastically connected by 0, resonance of the torsion beam 12 can be suppressed, which is effective in suppressing road noise. Note that it is naturally possible to add the above-mentioned vibration damping material 60 to the torsion beam 44 according to the second embodiment.

Further, in the above-described embodiment, the trailing arm 14 is constituted by a pipe-shaped member. However, the present invention is not limited to this. Any shape may be used as long as the trailing arm 14 has a pair of opposed portions opposed in the vehicle width direction. It may be constituted by an open section such as a letter shape.

Further, in the above embodiment, the torsion beams 12, 44 are constituted by the three beams 28, 30, 32, but the invention is not limited to this.

Further, in the above embodiment, the beams 28,
Although 30 and 32 are constituted by hollow members (pipes), they are not limited to this, and may be constituted by solid rod members.

[0038]

As described above, in the torsion beam type suspension according to the first aspect of the present invention, since the torsion beam is constituted by a plurality of hollow or solid rod members, the torsion beam, the trailing arm and the Can prevent warping from occurring at the joint portion of the torsion beam. As a result, the torsion beam can effectively function as a torsion beam while preventing excessive stress from being concentrated at the joint portion between the torsion beam and the trailing arm. It has an excellent effect that it can be performed.

According to a second aspect of the present invention, there is provided a torsion beam type suspension according to the first aspect, wherein the trailing arm has a pair of opposed portions facing each other in the vehicle width direction, and an end portion of each rod-shaped member. The end portion of the rod-shaped member and the two opposing portions are rigidly connected to each other in a state where the armature penetrates through the opposing portions of the trailing arm. Therefore, there is an excellent effect that the rigidity with respect to the camber angle of the trailing arm can be ensured.

According to a third aspect of the present invention, there is provided a torsion beam type suspension according to the first or second aspect, wherein a part of the plurality of rod-like members is moved substantially forward with respect to the remaining rod-like members. Because of the offset arrangement, it is possible to increase the constraint on the trailing arm in the horizontal plane of the vehicle, and as a result, there is an excellent effect that the rigidity of the trailing arm with respect to the toe angle can be secured.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a torsion beam type suspension according to a first embodiment.

FIG. 2 is a partial cross-sectional view showing a coupling portion between a beam and a trailing arm shown in FIG. 1;

FIG. 3 is a perspective view showing a torsion beam suspension according to a second embodiment.

FIG. 4 is a partial cross-sectional view showing another embodiment of the coupling configuration shown in FIG. 2;

FIG. 5 is a perspective view corresponding to FIG. 1, showing an embodiment in which a vibration isolator is added to the configuration shown in FIG. 1;

FIG. 6 is a plan view of a torsion beam type rear suspension according to a conventional example.

FIG. 7 is an explanatory diagram for explaining a problem of a conventional example.

[Explanation of symbols]

 Reference Signs List 10 torsion beam type suspension 12 torsion beam 14 trailing arm 14A side (opposing portion) 14B side (opposing portion) 28 beam (rod) 30 beam (rod) 32 beam (rod) 40 torsion beam suspension 42 trailing arm 44 Torsion beam 52 Beam (rod-like member) 54 Bolt-like member 58 Nut

Claims (3)

[Claims] 1. A torsion beam arranged longitudinally in the vehicle width direction, and a pair of trailing arms rigidly coupled to both longitudinal ends of the torsion beam and arranged longitudinally substantially in the vehicle longitudinal direction. ,
A torsion beam type suspension comprising: a plurality of hollow or solid rod-shaped members, each of which comprises the torsion beam. 2. The trailing arm has a pair of opposed portions facing each other in the vehicle width direction, and the end of each of the bar-shaped members penetrates both opposed portions of the trailing arm, and the trailing arm has a rod-like shape. The torsion beam type suspension according to claim 1, wherein an end portion of the member and the both opposing portions are rigidly connected to each other. 3. The torsion beam type suspension according to claim 1, wherein a part of the plurality of rod-shaped members is offset from a remaining rod-shaped member substantially toward the front of the vehicle. .