WO2013171828A1

WO2013171828A1 - Torsion beam type suspension

Info

Publication number: WO2013171828A1
Application number: PCT/JP2012/062321
Authority: WO
Inventors: 紳司田村; 暢昭寒川
Original assignee: 株式会社ヨロズ
Priority date: 2012-05-14
Filing date: 2012-05-14
Publication date: 2013-11-21

Abstract

[Problem] To provide a torsion beam type suspension in which the roll rigidity of the suspension can be adjusted without greatly adding to the weight. [Solution] The present invention provides a torsion beam type suspension (100) in which torsion beams (11) that extend in the right and left direction of a vehicle body are joined to right and left trailing arms (12) that extend in the front and back direction of a vehicle body and rock up and down, wherein the torsion beams are formed in a U-shape in the cross section that is perpendicular to the right and left direction of the vehicle body, and thin sheets of reinforcing material (40) in a thin sheet shape for reinforcing the torsion beams are provided in the inside of the U-shaped portion of the torsion beams.

Description

Torsion beam type suspension

The present invention relates to a torsion beam suspension in which the wheels of a vehicle are suspended by a suspension having a torsion beam.

In the torsion beam type suspension, a torsion beam is disposed between a pair of left and right trailing arms disposed generally in the longitudinal direction of the vehicle, and both ends of the torsion beam are welded to the trailing arms.

Since the cross-sectional shape of the junction between the trailing arm and the torsion beam changes significantly, stress concentration is likely to occur at the junction when the vehicle turns or the like. In Patent Document 1 below, the trailing arm is composed of an upper member formed in a curved shape and a lower member for reinforcing the upper member, and the lower member exceeds not only the upper member but also the welded portion between the trailing arm and the torsion beam. It is configured to be joined to the torsion beam.

JP, 2010-208549, A

The suspension needs to adjust not only the strength of the joint portion but also the roll rigidity of the torsion beam to a predetermined value when the vehicle turns or the like. The cross section of the torsion beam may be U-shaped to adjust the roll stiffness, and a solid or hollow roll bar may be disposed inside the torsion beam to adjust the roll stiffness.

In order to adjust the roll stiffness of the suspension, a design is made such as increasing the thickness of the roll bar, but the roll bar is a component which extends to the same extent as the width direction of the vehicle as the torsion beam. Therefore, the increase in weight due to the increase in wall thickness can not be said to be small among many auto parts. In the recent provision of fuel-efficient vehicles as well, weight reduction of parts is very carefully managed, and weight reduction is one of the important issues to be achieved in a torsion beam type suspension.

Therefore, the present invention was invented to solve the above-mentioned problems, and it is an object of the present invention to provide a torsion beam type suspension capable of adjusting the roll rigidity of the suspension without significantly increasing the weight.

The present invention for achieving the above object is a torsion beam type suspension in which a torsion beam extending in the left-right direction of the vehicle body is joined to left and right trailing arms extending in the front-rear direction of the vehicle body and swinging up and down. A thin plate reinforcing member, which is formed in a U-shape in a cross section perpendicular to the U-shape, and which reinforces the torsion beam is attached to the U-shaped inside of the torsion beam.

According to the torsion beam type suspension according to the present invention, the thin plate reinforcing member for reinforcing the torsion beam is provided inside the U shape of the torsion beam having the U-shaped cross section. Therefore, even if the members are joined in order to adjust the roll rigidity, the thin plate reinforcing member is thin, so that the shape can be added only to the portion necessary for adjusting the rigidity, without significantly increasing the weight. Roll stiffness can be adjusted.

It is a schematic perspective view showing a torsion beam type suspension concerning one embodiment of the present invention. It is a bottom view showing the same suspension. FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 1; It is a top view which shows the board | plate material before welding an upper member. FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 4; FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 4; It is sectional drawing which shows the relationship between a welding wire and a lower member.

Hereinafter, embodiments of the present invention will be described with reference to the attached drawings. The following description does not limit the technical scope or the meaning of terms described in the claims. Also, the dimensional proportions of the drawings are exaggerated for the convenience of the description, and may differ from the actual proportions.

FIG. 1 is a schematic perspective view showing a torsion beam type suspension according to an embodiment of the present invention, FIG. 2 is a bottom view showing the same suspension, and FIG. 3 is a sectional view taken along line 3-3 in FIG.

The torsion beam type suspension 100 according to the present embodiment is a rear suspension for suspending a rear wheel of a vehicle. The suspension 100 has an upper member 10, a lower member 20, a roll bar 30, and a thin plate reinforcing member 40 as shown in FIG. 1, and the lower member 20 is generally formed by being welded to the lower surface open portion of the upper member 10. Be done.

The upper member 10 is in contact with the main body of the torsion beam type suspension 100, and one torsion beam 11 extending in the left-right direction of the vehicle (in the vehicle width direction, arrow X direction in the drawing) A pair of left and right trailing arms 12 extending in the front-rear direction (a direction orthogonal to the vehicle width and in the direction of arrow Y in the figure), and a spring seat 13 provided between the torsion beam 11 and the trailing arms 12; including.

The torsion beam 11 is a U-shaped beam whose cross section is open at the lower side and is disposed between the two trailing arms 12 and its end is joined to the trailing arm 12.

The trailing arm 12 is disposed to be separated from each other on the left and right sides of the vehicle body, and provided at the front end portion with a mounting portion 14 for pivotally connecting the trailing arm 12 to the vehicle body in the vertical direction. The spindle 16 is provided with a support plate 15 for mounting on the wheel.

The spring seat 13 is a fixed end that mounts a spring and elastically supports the vehicle body. Since the spring seat 13 may narrow the indoor space of the vehicle body depending on the place where it is installed, it is preferable to provide it, for example, in the vicinity of the intersection between the torsion beam 11 and the trailing arm 12 as shown in FIG.

The lower member 20 is a reinforcing plate for reinforcing the trailing arm 12, and as shown in FIG. 1, the main plate portion 21 covering the lower surface of the trailing arm 12 of U-shaped cross section and the lower surface of the torsion beam 11 from the main plate portion 21. And an extending portion 22 extended so as to face the opening 11 a and integrally formed with the main plate portion 21.

The main plate portion 21 covers the lower surface opening 12a of the trailing arm 12, and by forming a closed cross section, the strength of the trailing arm 12 is improved to such an extent that the spring seat 13 can be attached.

It is preferable that the extension portion 22 be extended slightly beyond the position of the weld line W shown in FIG. 2 because the extension portion 22 affects the torsional rigidity of the trailing arm 12 if the extension portion 22 is extended.

By this configuration, even if the torsion beam 11 is twisted, the extension 22 of the lower member 20 can reinforce the welded portion of the trailing arm 12 and the torsion beam 11, and the stress concentration on the welded portion can be avoided. In addition, the strength of the entire trailing arm 12 can also be improved.

The roll bar 30 is a hollow or solid round bar-like member, and is provided to adjust the roll rigidity to a predetermined value with respect to the input to the suspension when the vehicle is turned or the like. The roll bar 30 is attached by being welded through to the side of the trailing arm 12 of U-shaped cross section.

The thin plate reinforcing member 40 has an outer portion 41, an inner portion 42, and a jig mounting hole 43, and is joined by welding or the like to the U-shaped inside of the torsion beam 11 having a U-shaped cross section. Adjust the roll stiffness. As shown in FIG. 3, the outer shape portion 41 is formed in substantially the same shape as the internal shape of the U-shaped cross section of the torsion beam 11.

The inner portion 42 is shaped to avoid the roll bar 30 so that the roll bar 30 can be attached to the inside of the torsion beam 11, and its width is slightly wider than the outer diameter of the roll bar 30. In order to prevent the roll bar 30 from being deformed by contact with the roll bar 30 even when the torsion beam 11 is deformed due to an external force or the like, the inner shape portion 42 provides a gap with the roll bar 30 so as not to abut. It is formed.

The jig mounting hole 43 is formed as a mounting hole for jig mounting at the time of joining to the upper member 10. The thin plate reinforcing member 40 is attached to the vicinity of the boundary between the trailing arm 12 and the torsion beam 11 whose cross-sectional shape largely changes in the lateral direction of the torsion beam type suspension, but the specific position is determined from analysis and actual experimental results. Be done.

In the present embodiment, as shown in FIGS. 1 and 2, the thin plate reinforcing members 40 are provided at two places near the joint portion between the torsion beam 11 and the trailing arm 12, but as described above, thin plates are obtained from analysis and experimental results. The reinforcing member 40 can be provided at two different places from those in FIGS. 1 and 2 without being limited to two places. The thin plate reinforcing member 40 has a weight of about several tens of grams, and is a sufficiently lightweight member as compared to the torsion beam 11 and the roll bar 30. In addition, since a plurality of thin plate reinforcing members 40 can be attached to the U-shaped inside of the torsion beam 11 regardless of the length of the torsion beam 11 or the roll bar 30, it can be provided only in the necessary part. It is possible to suppress the increase.

The torsion beam 11, trailing arm 12, spring sheet 13, main plate 21, extension 22, roll bar 30, and thin plate reinforcing member 40 are made of, for example, a hot-rolled steel plate, and each plate has a thickness of about 1 to 2 mm. Although it comprises, it is not limited to this.

4 is a plan view showing the plate before welding the upper member, FIG. 5 is a sectional view taken along the line 5-5 in FIG. 4, FIG. 6 is a sectional view taken along the line 6-6 in FIG. It is the schematic which shows the relationship between the welding wire of the board | plate materials which comprise a member, and a lower member.

In the case of forming the torsion beam type suspension, in order to form the upper member 10, for example, a plate material as shown in FIG. 4 is prepared. In the present embodiment, the upper plate 10 uses a substantially trapezoidal plate 11 p as the torsion beam 11, a substantially bowl-shaped plate 12 p as the trailing arm 12, and a substantially rectangular plate 13 p as the spring sheet 13. However, these shapes can be appropriately selected according to the actual product shape.

Among the

plates

11p, 12p and 13p, the plate thickness t2 of the plate 12p used for the trailing arm 12 is preferably thinner than the plate thickness t1 of the plate 11p used for the torsion beam 11, as shown in FIG. By this configuration, it is possible to reduce the weight of the trailing arm 12 while enhancing the torsional rigidity of the torsion beam 11.

The plate thickness t3 of the plate 13p used for the spring sheet 13 is preferably larger than the plate t2 of the trailing arm 12 as shown in FIG. 6 because the strength of the spring sheet 13 to which a load is applied is improved. Of course, the plate thickness t3 of the plate 13p of the spring sheet 13 may be thicker than the plate thickness t1 of the plate 11p of the torsion beam 11, and the strength may be further enhanced. The plate thicknesses of the

plate members

11p, 12p and 13p may be different from each other, but at least the plate thicknesses of the

plate members

12p and 11p are different in consideration of the improvement of the torsional rigidity of the torsion beam 11 and the strength of the trailing arm 12 It is preferable to

After the plate material is prepared, the

plate materials

11p, 12p, and 13p used for the upper member 10 are joined to each other by butt welding. A weld line W1 is formed between the plate material 11p and the plate material 12p used for the torsion beam 11 by butt welding, and a weld line W2 is formed between the plate material 11p and the plate material 13p used for the spring sheet 13. The plate material 12p and the plate material 13p And a weld line W3 is formed therebetween.

As described above, welding lines W1, W2 and W3 shown by broken lines in FIG. 7 are formed on the upper member 10, and two or more plates having different thicknesses are joined to form a tailored blank. By forming the tailored blank material, it is possible to set the plate thickness, the material, and the like for each part, and to suppress the increase in weight, cost, and the like while securing strength, rigidity, and the like. In the present embodiment, different types of plate materials indicate plate materials having different plate thicknesses and materials of members, and different surface treatments. Moreover, although the tailored blank material was comprised with the board | plate material of 3 sheets in this embodiment, a board material is not limited to 3 sheets, You may comprise with 2 sheets.

After the tailored blank material is formed, the upper member 10 to which three plate members are joined is press-formed. As a result, as shown in FIG. 1, the torsion beam 11 and the trailing arm 12 have a U-shaped cross section perpendicular to the longitudinal direction, and the spring sheet 13 is formed on the seat portion receiving the spring.

After the upper member 10 is formed, the thin plate reinforcing member 40 is welded to the inside of the U-shaped cross section torsion beam 11. When the upper member 10 is formed into a U-shaped cross section by press molding, the upper member 10 can not be stably grounded when the thin plate reinforcing member 40 is joined, which may make the joining operation complicated. Therefore, it is preferable to attach a jig to the jig attachment hole 43 at the time of joining.

Next, the roll bar 30 is penetrated to the side part of the upper member 10 and welded. After the roll bar 30 is attached, bonding is performed so as to close the lower surface opening 12a of the trailing arm 12 by the main plate portion 21 of the lower member 20 which is separately punched and formed.

The outer peripheral edge of the lower member 20 is formed so as to exceed the line obtained by projecting the welding lines W1, W2 and W3 in the bottom view shown in FIG. 2 or 7, and it is preferable to weld the lower member 20 and the upper member 10 together. . By this configuration, when the torsion beam 11 is twisted and a load is applied to the spring seat 13, the lower member 20 reinforces the welded portion of the upper member 10 to avoid stress concentration on the welded portion. it can.

In order to adjust the roll rigidity of the torsion beam type suspension at the time of turning or the like, the outer diameter of the roll bar or the outer diameter if the roll bar is hollow in order to adjust the thickness of the roll bar attached to the upper member. Adjusts the inner diameter.

However, since the roll bar is a member whose cross section is formed uniformly by extrusion molding or the like, if the thickness is changed in order to adjust the roll rigidity, a portion other than the portion to be reinforced because the cross section is uniform. The wall thickness will increase, which will increase the weight. The roll bar 30 is a member whose length is about 1 m or more, which is about the same as the width of the vehicle body, and weighs several hundreds of grams. Even if the diameter is adjusted about several millimeters, even parts not necessary for reinforcement Increasing the thickness is not appropriate from the viewpoint of fuel efficiency and cost efficiency.

On the other hand, in the torsion beam type suspension 100 according to the present embodiment, the diameter of the roll bar 30 extending to 1 m or more is adjusted by joining the thin plate reinforcing member 40 having a thickness of 2 mm and several tens of grams to the torsion beam 11 It is possible to add the shape only to the place required for rigidity increase as compared with. As a result, the roll stiffness can be adjusted to a predetermined value while minimizing the increase in weight, and by making the suspension lightweight, it can also contribute to the reduction of the fuel consumption of the vehicle.

As described above, in the torsion beam type suspension 100 according to the present embodiment, the thin plate reinforcing member 40 is provided inside the torsion beam 11 having a U-shaped cross section. Therefore, it is possible to add the shape only to the part necessary to adjust the roll rigidity, adjust the roll rigidity without causing a significant increase in weight, and reduce the weight and cost of the entire suspension, and reduce the fuel consumption of the vehicle. Can also contribute.

Further, since the inner portion 42 of the thin plate reinforcing member 40 is formed to avoid the roll bar 30 so that the roll bar 30 can be attached to the upper member 10, the roll bar 30 can be attached together with the thin plate reinforcing member 40 By this, the roll stiffness can be adjusted widely.

Further, a plurality of thin plate reinforcing members 40 are configured to be attached to the U-shaped inside of the torsion beam 11. Therefore, it is possible to appropriately add the shape necessary for enhancing the rigidity according to the analysis or the experimental result to the necessary portion, and the roll rigidity can be widely adjusted without significantly increasing the weight.

The upper member 10 is configured of a tailored blank in which different types of plate members are combined and joined. Therefore, setting of plate thickness, material and the like can be performed for each part, and increase in weight, cost and the like can be suppressed while securing strength and rigidity and the like.

The present invention is not limited to the embodiments described above, and various modifications are possible within the scope of the claims.

Although the embodiment in which the jig attachment hole 43 is provided in the thin plate reinforcing member 40 has been described, the jig attachment hole 43 may not be formed if the thin plate reinforcement member 40 can be attached without using a jig.

10 upper members,
100 torsion beam suspension,
11 torsion beams,
11a bottom opening,
11p plate material,
12 trailing arms,
12a bottom opening,
12p plate material,
13 spring seat,
13p plate material,
14 mounting parts,
15 support plates,
16 spindles,
20 lower members,
21 main plate,
22 extensions,
30 roll bars,
40 sheet reinforcement members,
41 outer part,
42 internal parts,
43 jig mounting holes,
W, W1, W2, W3 welding wire,
t1, t2, t3 thickness.

Claims

In a torsion beam type suspension in which torsion beams extending in the left-right direction of the vehicle body are joined to left and right trailing arms extending in the front-rear direction of the vehicle body and swinging up and down, the torsion beam is U-shaped in a cross section orthogonal to the left-right direction of the vehicle body A torsion beam type suspension characterized in that a thin plate reinforcing member for reinforcing the torsion beam is attached to the U-shaped interior of the torsion beam.
The torsion beam according to claim 1, wherein a roll bar is disposed inside the U-shape of the torsion beam and joined to the trailing arm, and the thin plate reinforcing member is formed in a shape avoiding the roll bar. Type suspension.
The torsion beam type suspension according to claim 1 or 2, wherein a plurality of the thin plate reinforcing members are attached to a U-shaped inside of the torsion beam.
The torsion beam type suspension according to any one of claims 1 to 3, wherein the main body of the torsion beam type suspension is constituted by a tailored blank in which different types of plate members are combined and joined.