JP3604951B2 - Trailing arm suspension - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a trailing arm type suspension including a torsion beam.
[0002]
[Prior art]
As an example of a conventionally known trailing arm suspension, an arm member is fixed to both ends of a torsion beam extending in the vehicle width direction. In this type of suspension, the torsion beam and the arm member are basically configured separately, and the torsion beam is located along the vehicle width direction and the arm member is located along the front-rear direction of the vehicle. . A bush for attachment to the vehicle body is provided on the front side of such an arm member, and a spindle for mounting wheels is provided on the rear side of the arm member. Such an arm member is capable of swinging up and down around the mounting bush.
[0003]
On the other hand, the torsion beam absorbs and absorbs the input by causing torsional deformation or the like when there is an input that causes a vertical step between the pair of left and right arm members. Therefore, the torsion beam is made of, for example, a rolled steel material having a U-shaped cross section so as to easily cause torsional deformation. Such a torsion beam and an arm member are joined and fixed by butt welding in a shape orthogonal to each other, and the fixed portion is a weld joint.
[0004]
[Problems to be solved by the invention]
However, in the above-described conventional trailing arm type suspension, the torsion beam has a U-shaped cross section over its entire length, and both ends of the torsion beam which is torsionally deformed are simply butt-welded to the arm member. Therefore, in such a butt welding, the welded joint is easily affected by the torsional deformation of the torsion beam, and continuous welding is difficult because the torsion beam has a U-shaped cross section. However, there is a problem that the strength reliability of the welded joint cannot be improved.
[0005]
The present invention has been conceived under the circumstances described above, and enables continuous welding or the like at a predetermined fixed portion between the torsion beam and the arm member, and improves the strength reliability at such a fixed portion. SUMMARY OF THE INVENTION It is an object of the present invention to provide a trailing arm type suspension.
[0006]
DISCLOSURE OF THE INVENTION
In order to solve the above problems, the present invention employs the following technical means.
[0007]
That is, trailing arm provided by the present invention has an arm portion extending in the longitudinal direction of the vehicle at both end portions of the torsion beam extending in the vehicle width direction, the mounting bush to the vehicle body on the front side of the arm portion while Ru provided Tei, a Tei Ru trailing arm structure for wheel mounting is provided on the rear side of the arm part, the torsion beam is a sectional hollow and the tubing over the intermediate portion from the two end portions The intermediate portion has an inwardly bent portion, and the both end portions are bent rearward of the vehicle to form a rear portion of the arm portion , are formed separately from the torsion beam, and An arm member constituting a front portion of the arm portion is provided, and the arm member has an inner portion in the vehicle width direction and an open rear portion. A bent portion of the torsion beam is fitted into an opening at the rear of the arm member, and the rear end of the U-shaped rear view of the arm member is welded to the torsion beam. The arm member is characterized in that the welded rear end is wider than the front end in plan view .
[0008]
In the trailing arm type suspension provided by the present invention in which the above technical means have been taken, first of all, the torsion beam has a hollow section in the whole thereof and a portion which is bent inward in the middle part, An intermediate portion along the vehicle width direction is apt to cause torsional deformation. In addition, since both ends of the torsion beam have a hollow cross section by being bent, the torsion beam has a rigid portion that is resistant to torsional deformation force in contrast to the inwardly bent intermediate portion. I can say. In addition, both end portions of the bent torsion beam can swing up and down as part of the arm portion. Second, the arm member is fixed outside the vicinity of both ends of the torsion beam as the other part of the arm part. That is, the arm member is swingable in the vertical direction integrally with both ends of the torsion beam, and is joined and fixed via a welding joint such as welding.
[0009]
The fixing point of the arm member by such welding is located outside the vicinity of both ends of the torsion beam, but since the vicinity of both ends of the torsion beam has rigidity different from the intermediate part, the fixing point of the torsion beam The effect of torsional deformation is considered to be difficult. Further, in order to fix the arm member by welding or the like, an arm member that matches the bent outer surface of the torsion beam is used. In such an arm member, a predetermined portion to be fixed is along the outer surface of the torsion beam. Because of the shape, continuous welding can be easily performed at the fixed portion, and a sufficient welding length can be secured.
[0010]
Therefore, according to the trailing arm type suspension according to the present invention, the arm member can be fixed by welding or the like to the outside near both ends where the torsion beam is hardly affected by the torsional deformation, and continuous welding can be performed. Since it is possible, the strength reliability of the torsion beam and the arm member can be improved by using such a fixed portion as a weld joint.
[0011]
Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.
[0013]
FIG. 1 is a perspective view partially showing an embodiment of a trailing arm type suspension according to the present invention, FIG. 2 is a sectional view showing a cross section taken along line XX shown in FIG. 1, and FIG. 1, and FIG. 4 is a plan view showing the entire outer shape of the trailing arm type suspension shown in FIG. 1 and 4, the arrow N1 direction is the front of the vehicle, and the arrow N2 direction is the vehicle width direction.
[0014]
As shown in these drawings, the trailing arm type suspension A according to the present invention welds the arm member 11 to the vicinity of both ends 10a of the torsion beam 10 extending in the vehicle width direction N2 so as to be along the front-rear direction of the vehicle. It has a fixed configuration. In this type of suspension, a pair of right and left arms is generally constituted by arm members. The suspension A shown as an example of the present invention is characterized in that the rear portion of the arm is provided by the torsion beam 10. The configuration is such that both ends 10 a are formed, and the front portion of the arm is formed by the arm member 11.
[0015]
As shown in FIGS. 1 and 4, the torsion beam 10 is made of, for example, a circular or elliptical steel pipe having a predetermined thickness and a hollow cross section. The intermediate portion 10b of the torsion beam 10 is arranged along the vehicle width direction W, and both end portions 10a are bent toward the vehicle rear side to form a rear portion of the arm portion. Further, the extreme end portions 10aa of the both end portions 10a are bent outward in the vehicle width direction N2, and a spindle shaft 12 or the like is provided at that portion as an example for wheel attachment. In the intermediate portion 10b of the torsion beam 10, a portion 10ba that is bent inward toward the inner side is formed so that the cross section is better shown in FIG. The inner bending portion 10ba is formed to absorb or reduce the input by causing torsional deformation or the like when there is an input that causes a step in the vertical direction with respect to both ends 10a of the torsion beam 10. The inner bent portion 10ba is formed by deforming the steel pipe into a predetermined cross-sectional shape by high-hydraulic press working or the like. Further, the inner bent portion 10ba is formed over a predetermined length only in the intermediate portion 10b without reaching the both end portions 10a of the torsion beam 10. In the present embodiment, the inner bending portion 10ba is disposed toward the front N1 of the vehicle, but may be disposed rearward, upward, or downward depending on the degree of the torsional deformation. .
[0016]
On the other hand, both end portions 10a of the torsion beam 10 have an outer shape along the front-rear direction of the vehicle over a predetermined length, and when viewed from the cross section, as shown in FIG. Have been. Further, the outer surface of the portion 10ab bent from the intermediate portion 10b to the both end portions 10a is a curved surface that is curved toward the vehicle front N1 side, and an arm member 11 described later is welded to the portion. Is fixed by Since both end portions 10a thus bent are hollow and have excellent strength in the form of a hollow cross section, a certain amount of resistance against the torsion deformation of the inner bending portion 10ba of the intermediate portion 10b is provided. Rigidity is maintained. Note that both end portions 10a of the torsion beam 10 are vertically swingable integrally with an arm member 11 described later.
[0017]
As shown in FIGS. 1 and 4, the arm member 11 is made of, for example, a steel material having a predetermined thickness U-shaped opening 11aa and a curved concave portion 11ab. The arm member 11 is disposed on the front side of the torsion beam 10 along the front-rear direction of the vehicle, and a bush 13 for attachment to a vehicle body (not shown) is welded to the front most front end portion 11b by welding or the like. It is firmly fixed. On the other hand, the rear end portion 11c of the arm member 11 is fixed to a predetermined portion of the torsion beam 10 via a welding joint such as welding, so that the rear end portion 11c has a predetermined edge shape that matches and abuts the surface of the fixed portion. It has been processed. That is, the arm member 11 is joined and fixed by welding or the like to the outer surface of the bent portion 10ab whose outermost end 11c is located outside the vicinity of both ends 10a of the torsion beam 10, and the mounting bush 13 is used as a fulcrum. It is swingable in the vertical direction integrally with the portion 10a. The arm member 11 has a flared shape in which the rearmost end 11c is larger than the foremost end 11b in order to obtain a required welding bonding force at a position where the arm member 11 is fixed to the torsion beam 10. In the rear end portion 11c of such an arm member 11, welding is continuously performed on the edge thereof, and the arm member 11 is wrapped around from the lower side to the outer side through a weld joint that continues upward without interruption. And is firmly fixed to the torsion beam 10.
[0018]
The gist of the present invention is that the entire arm portion that swings up and down is formed of separate parts of the both end portions 10a of the torsion beam 10 and the arm member 11, and these two components are integrated. By doing so, the torsion beam 10 and the arm member 11 are not fixed by butt welding as in the related art, but the arm member 11 is fitted to the outer surface of the torsion beam 10 as well shown in FIG. However, the portions that contact each other (the portions indicated by reference numeral 11c in FIGS. 1 and 4) are fixed as welded joints. Since such a fixed portion by welding is provided on the outer surface of the bent portion 10ab of the torsion beam 10, even if torsional deformation occurs in the torsion beam 10, it is hardly affected by the torsional deformation. It can be said that the torsion beam 10 and the arm member 11 joined to each other in a firmly connected state.
[0019]
Next, the operation of the trailing arm type suspension A having the above configuration will be described.
[0020]
First, when manufacturing the suspension A having the above-described configuration, the torsion beam 10 having the inner bent portion 10ba at the intermediate portion 10b and the bent portions 10ab at both end portions 10a is manufactured as described above. Then, the suspension A is completed by welding the rearmost end 11c of the arm member 11 to the outer surface of the predetermined portion 10ab of the torsion beam 10.
[0021]
At this time, the rear end 11c of the arm member 11 is continuously welded from the lower side to the upper side or vice versa along the shape of the curved concave portion 11ab. Such continuous welding is considered difficult if there is a corner at a predetermined length to be welded, but in the present embodiment, the rear end 11c of the arm member 11 has a gentle U-shaped cross section from the upper side to the lower side. Because of the continuous shape presented, continuous welding is relatively easy and a sufficient welding length can be secured.
[0022]
When the suspension A thus obtained is mounted on a vehicle and operates, the torsion beam 10 and the arm member 11 are integrated with each other in accordance with a vertical stroke movement via wheels (not shown) and the mounting bush 13 is used as a fulcrum. Rocks. In such a swinging operation, if there is an input that causes a step in the vertical direction between the left and right sides in the vehicle width direction N2, a torsion deformation or the like occurs in the intermediate portion 10b of the torsion beam 10, and the input is made by the inner bending portion 10ba. Absorption is reduced.
[0023]
Such torsional deformation of the torsion beam 10 is transmitted to both ends 10a as internal stress. However, since both ends 10a of the torsion beam 10 have a hollow cross section so as to have considerable rigidity against such torsional deformation force, most of the torsional deformation is in the middle of the torsion beam 10. Both ends 10a, which only occur at the part 10b and have the bent part 10ab, withstand considerable torsional deformation and remain in a constant form.
[0024]
That is, the arm member 11 is joined and fixed to the bent portions 10ab of the both end portions 10a of the torsion beam 10 by welding, but the fixed portions 10ab are fixed to the torsion beam 10 by torsional deformation. Since the operation is difficult, the state where the arm member 11 is firmly fixed to the torsion beam 10 is maintained even when the arm member 11 is subjected to torsional deformation.
[0025]
Therefore, according to the trailing arm type suspension A according to the present invention having the above-described configuration and operation, the arm member 11 is disposed outside the predetermined portions 10ab near both ends 10a where the torsion beam 10 is hardly affected by the torsional deformation. Since the arm member 11 can be fixed by welding in accordance with the outer shape of the torsion beam 10, the strength reliability of the torsion beam 10 and the arm member 11 can be improved by using such a fixed portion as a welding joint. Can be improved.
[Brief description of the drawings]
FIG. 1 is a perspective view partially showing an embodiment of a trailing arm type suspension according to the present invention.
FIG. 2 is a sectional view showing a section taken along line XX shown in FIG. 1;
FIG. 3 is a sectional view showing a section taken along line YY shown in FIG. 1;
FIG. 4 is a plan view showing the entire outer shape of the trailing arm type suspension shown in FIG. 1;
[Explanation of symbols]
A Trailing arm type suspension 10 Torsion beam 10a Both end portions 10b of torsion beam Intermediate portion 10ba of torsion beam Bend portion 11 Arm member 11c Last end portion of arm member (fixed point)
12 spindle shaft 13 mounting bush

Claims (1)

An arm portion extending in the longitudinal direction of the vehicle at both end portions of the torsion beam extending in the vehicle width direction, while Ru Tei mounting bushing is provided to the vehicle body on the front side of the arm portion, the wheel attached to the rear side of the arm part a Tei Ru trailing arm structure is provided for use,
The torsion beam is formed by a tube which was sectional hollow over the intermediate portion from both ends, and having an inner bending deformed portion to the intermediate portion, after the arm part said both end portions is bent rearward Form side parts ,
An arm member that is formed separately from the torsion beam and that constitutes a front portion of the arm portion is provided.
The arm member has a U-shaped cross section in which a vehicle width direction inner side portion and a rear portion are opened,
The bent portion of the torsion beam is fitted into the opening at the rear of the arm member, and the rear end of the U-shaped rear view of the arm member is welded to the torsion beam,
A trailing arm type suspension, wherein the rear end of the arm member to which the welding is applied is wider than a front end of the arm member in plan view .

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