JP2008114635A - Torsion beam type suspension - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a torsion beam type suspension ensuring practical rigidity with simple constitution. <P>SOLUTION: The torsion beam type suspension 10 comprises a torsion beam 12 whose longitudinal direction is the cross direction of a vehicle, and a pair of plate-like trailing arms 14 joined to both ends of the torsion beam 12 and extending in the longitudinal direction of the vehicle. The torsion beam 12 has a spring support part 22 for supporting a spring for relieving vibration from the road surface, on the end side where the vehicle longitudinal width of the torsion beam 12 is formed wider than the center part. The spring support part 22 is formed so that a cross section intersecting the longitudinal direction of the vehicle is a closed cross section. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a torsion beam suspension for a vehicle such as an automobile.

Conventionally, a torsion beam suspension having a trailing arm is known. Patent Document 1 discloses a torque arm type rear suspension in which a pair of left and right spring receivers and a shock absorber mounting bracket are formed on the left and right ends of a rear axle, respectively. In Patent Document 2, a trailing arm extends in the vehicle front-rear direction, a front end portion of the trailing arm is connected to a vehicle body side member via a bush, and a wheel support member and a shock absorber are provided on the rear end side. A suspension in which a lower part is arranged is disclosed. Patent Document 3 includes a pipe portion formed by bending a part of a single metal plate, and a spring seat portion formed by processing into a shape on which a coil spring can be placed. A trailing arm is disclosed.
Japanese Patent Laid-Open No. 10-16526 JP 2001-88525 A JP 2000-335219 A

  However, the suspension described above has a problem that the shape of the trailing arm is complicated, and many steps are required for processing, and the number of components is increased. In addition, when the shape of the trailing arm is three-dimensional and complicated, the trailing arm and the torsion beam need to be processed in consideration of the shape of the joint portion of each other, which causes a decrease in productivity.

  Moreover, in the suspensions described in Patent Document 2 and Patent Document 3, a spring seat portion that holds one end of the coil spring is provided by welding or bending. However, since one end of the spring seat portion is only supported by the trailing arm, it is easy to bend due to the structure and it is difficult to ensure rigidity.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a torsion beam suspension that ensures practical rigidity with a simple configuration.

In order to solve the above-described problems, a torsion beam suspension according to an aspect of the present invention is a pair of torsion beams having a longitudinal direction in the vehicle width direction of a vehicle and both ends of the torsion beam and extending in the front-rear direction of the vehicle. Plate-shaped trailing arm. The torsion beam has a spring support portion for supporting a spring for reducing vibration from the road surface on an end portion side where the width of the torsion beam in the front-rear direction of the vehicle is wider than the center portion. The spring support portion is formed so that a cross section intersecting with the vehicle front-rear direction is a closed cross section.
According to this aspect, since the spring support portion is formed on the torsion beam, it is not necessary to provide the spring support portion as a separate member on the trailing arm, and the number of parts can be reduced. Further, since the spring support portion has a closed cross-sectional structure, the support rigidity can be improved. In other words, compared to the case where one end of the spring support portion is fixed to the trailing arm in a cantilever state, at least the cross section intersecting with the longitudinal direction of the vehicle is formed as a closed cross section. The spring support portion is less likely to be deformed even when the spring contracts due to the vertical input of the vehicle and a force acts on the spring support portion. In other words, when the same amount of deformation is allowed for a predetermined input, the thickness of the members constituting the closed section and the range of selection of materials are widened, so that the design can be facilitated and the cost can be reduced.

  The spring support portion may have a closed cross section formed by the trailing arm and the torsion beam. As a result, the trailing arm and the torsion beam can suppress the deformation of each other, and the rigidity of the entire torsion beam suspension can be improved.

  The spring support portion may be formed rearward in the front-rear direction of the vehicle from the center portion of the torsion beam, and the torsion beam may be joined to the trailing arm from the spring support portion to the rearward direction of the vehicle. Since the trailing arm is a plate-like member, it is relatively easy to join the torsion beam to the trailing arm over a wide range in the front-rear direction of the vehicle, and productivity and workability can be improved. Moreover, the rigidity with respect to the input to the trailing arm in the vehicle width direction can be improved.

  The torsion beam may have an absorber support portion for supporting an absorber for damping vibration on the end side. The absorber support portion may be formed so that a cross section intersecting with the vehicle front-rear direction is a closed cross section. Since the absorber support part is formed in the torsion beam, it is not necessary to provide the absorber support part in the trailing arm as a separate member, and the number of parts can be reduced. Further, since the absorber support part has a closed cross-sectional structure, the support rigidity can be improved.

  According to the present invention, it is possible to provide a torsion beam type suspension that ensures practical rigidity with a simple configuration.

  The best mode for carrying out the present invention will be described below in detail with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and repeated descriptions are omitted as appropriate. FIG. 1 is a top view schematically showing a part of the torsion beam suspension according to the present embodiment.

  As shown in FIG. 1, the torsion beam suspension 10 has a torsion beam 12 disposed with the vehicle width direction of the vehicle as a longitudinal direction, and extends at both ends of the torsion beam 12 in the longitudinal direction with the longitudinal direction of the vehicle as a longitudinal direction. A pair of left and right trailing arms 14. That is, the torsion beam 12 is disposed so as to connect the pair of trailing arms 14.

  Each trailing arm 14 is formed of a plate-shaped metal member. Further, a bush 16 having an axial direction in the vehicle width direction is attached to one end side 14a of the trailing arm 14 on the vehicle front side, and the trailing arm 14 can swing toward the vehicle body via the bush 16. And elastically supported.

  Further, a wheel bearing is attached to the other end side 14b of the trailing arm 14 on the vehicle rear side, and a unit bearing 18 that rotatably supports the wheel is fixed by a bolt. The torsion beam 12 is joined between one end and the other end of the side surface on the vehicle inner side of the trailing arm 14 supported by the vehicle body. By joining the torsion beam 12 and the trailing arm 14 at such a location, the suspension functions using both rigidity against bending and rigidity against torsion.

  The torsion beam 12 according to the present embodiment is formed such that the width of the vehicle in the front-rear direction is wider on the end side joined to the trailing arm 14 than in the center. And the spring support part 22 which supports the spring 20 for relieving the vibration from a road surface is provided in the edge part side where the torsion beam 12 was extended toward the back of the vehicle. The spring support portion 22 is formed at the rear in the front-rear direction of the vehicle from the center portion of the torsion beam 12. Further, the torsion beam 12 is joined to the trailing arm 14 from the spring support portion 22 to the rear in the front-rear direction of the vehicle. Since the trailing arm 14 is a plate-like member, it is relatively easy to join the torsion beam 12 to the trailing arm 14 over a wide range in the front-rear direction of the vehicle, and productivity and workability can be improved. .

  Further, the torsion beam 12 is provided with an absorber support portion 26 for supporting the absorber 24 for damping the vibration behind the spring support portion 22. The absorber support part 26 is comprised from the opening part 26a formed in the upper surface part of the torsion beam 12, and the rotating shaft 26b arrange | positioned inside the opening part 26a. The absorber 24 is rotatably attached to the rotating shaft 26b.

  Next, the cross-sectional shape of the torsion beam 12 will be described in detail with reference to FIGS. FIG. 2 is an AA cross section of the torsion beam 12 shown in FIG. 3 is a BB cross section of the torsion beam 12 shown in FIG. 4 is a CC cross section of the torsion beam 12 shown in FIG. FIG. 5 is a DD cross section of the torsion beam 12 shown in FIG.

  The torsion beam 12 according to the present embodiment is manufactured by appropriately joining a plurality of plate-like members that have been pressed or bent by welding. The torsion beam 12 has a U-shaped cross section in which the lower part is opened as shown in FIG. 2 in the vicinity of the center in the vehicle width direction by processing the plate-like upper member 12a.

  Further, the torsion beam 12 has a cross section shown in FIG. 3 in the vicinity of the spring support portion 22 formed on the end side thereof. In the torsion beam 12, the upper member 12 a and the lower member 12 b are joined at the welded portion 30 to form a spring support portion 22. The upper member 12a is formed with a convex portion 22a that directly supports the spring 20. The convex portion 22a is a circle having the same size as the inner diameter of the coiled spring 20, and can support the spring 20 so as not to be displaced.

  One end of the upper member 12a is joined to the trailing arm 14 at the welded portion 30, and the other end located inside the vehicle is bent downward by bending or pressing so that the lower member 12b and the welded portion 30 are joined. Are joined. Further, one end of the lower member 12 b is joined to the side surface on the vehicle inner side of the trailing arm 14 at the welded portion 30. As described above, the spring support portion 22 according to the present embodiment has a closed cross section in which the cross section intersecting the longitudinal direction of the vehicle is surrounded by the upper member 12a and the lower member 12b of the torsion beam 12 and the trailing arm 14. It is formed to become.

  In the torsion beam suspension 10 according to the present embodiment, the spring support portion 22 is formed on the torsion beam 12, so that it is not necessary to provide the spring support portion 22 such as a spring seat on the trailing arm 14 as a separate member, and the number of parts is reduced. Can be reduced. Further, since the spring support portion 22 has a closed cross-sectional structure, the support rigidity can be improved. That is, compared with the case where one end of the spring seat is fixed to the trailing arm 14 in a state like a cantilever, at least a cross section that intersects with the longitudinal direction of the vehicle is formed as a closed cross section. The spring support portion 22 is not easily deformed even when the spring 20 contracts due to the vertical input of the vehicle and a force is applied to the spring support portion 22. In other words, when the same amount of deformation is allowed for a predetermined input, the thickness of the members constituting the closed cross section and the range of selection of materials are widened, so the torsion beam suspension 10 can be easily designed and the cost can be reduced. .

  Further, the torsion beam 12 has a cross section shown in FIG. 4 at a position behind the spring support 22 and where the unit bearing 18 is provided on the trailing arm 14. In this location, an opening 12c is provided in a part of the side surface of the upper member 12a on the vehicle inner side. Thereby, the workability | operativity at the time of attaching the unit bearing 18 to the trailing arm 14 with the volt | bolt 32 can be improved.

  The torsion beam 12 has a cross section shown in FIG. 5 in the vicinity of the absorber support portion 26 formed on the end side thereof. In the torsion beam 12 in the vicinity of the absorber support portion 26, the upper member 12 a and the lower member 12 b are joined at the weld portion 30. An opening 26a into which the absorber 24 is inserted is formed on the upper surface of the upper member 12a. The absorber 24 is rotatably supported by a rotating shaft 26b attached to the trailing arm 14 and the side surface of the upper member 12a.

  One end of the upper member 12a is joined to the trailing arm 14 at the welded portion 30, and the other end located inside the vehicle is bent downward by bending or pressing so that the lower member 12b and the welded portion 30 are joined. Are joined. Further, one end of the lower member 12 b is joined to the side surface on the vehicle inner side of the trailing arm 14 at the welded portion 30. As described above, the absorber support portion 26 according to the present embodiment has a closed cross section in which the cross section intersecting with the longitudinal direction of the vehicle is surrounded by the upper member 12a and the lower member 12b of the torsion beam 12 and the trailing arm 14. It is formed to become.

  In the torsion beam suspension 10 according to the present embodiment, since the absorber support portion 26 is formed on the torsion beam 12, there is no need to provide a member such as an absorber bracket as a separate member on the trailing arm 14, and the number of parts is reduced. be able to. Further, since the absorber support portion 26 has a closed cross-sectional structure, the support rigidity can be improved. That is, compared with the case where one end of the absorber bracket is fixed to the trailing arm 14 in a state like a cantilever, at least a cross section intersecting with the front-rear direction of the vehicle is formed as a closed cross section. The absorber support portion 26 is less likely to be deformed even when a force is applied via the absorber 24 by the vertical input of the vehicle. In other words, when the same amount of deformation is allowed for a predetermined input, the thickness of the members constituting the closed cross section and the range of selection of materials are widened, so the torsion beam suspension 10 can be easily designed and the cost can be reduced. .

  Next, a case where a bending moment acts on the torsion beam suspension 10 according to the present embodiment will be described. FIG. 6 is a schematic diagram for explaining a bending moment when there is an input to the spring support 22 from a certain direction. FIG. 7 is a schematic diagram for explaining a bending moment when there is an input to the absorber support 26 from a certain direction.

  As shown in FIGS. 6 and 7, when the torsion beam 12 receives an input from the spring 20 or the absorber 24 (see arrow R1), the torsion beam 12 and the trailing arm 14 joined thereto are centered on the X axis. The bending moment is applied. When the trailing arm 14 receives an input in the vehicle width direction from a wheel (not shown) mounted on the unit bearing 18 (see arrow R2), the trailing arm 14 and the torsion beam 12 joined thereto are A bending moment about the Y axis acts.

  In the torsion beam suspension 10 according to the present embodiment, a closed cross section is formed by the trailing arm 14 and the torsion beam 12 in the spring support portion 22 and the absorber support portion 26. Therefore, the trailing arm 14 and the torsion beam 12 can suppress deformation of each other, and the rigidity of the entire torsion beam suspension 10 can be improved.

  As described above, the present invention has been described with reference to the above-described embodiment. However, the present invention is not limited to the above-described embodiment, and the present invention can be appropriately combined or replaced with the configuration of the embodiment. It is included in the present invention. Various modifications such as design changes can be added to the embodiments based on the knowledge of those skilled in the art, and the embodiments to which such modifications are added can be included in the scope of the present invention. . Such modifications will be described below.

  FIG. 8 is a cross-sectional view showing a state in which the upper member 12a and the lower member 12b in the torsion beam 12 according to another embodiment are welded. Unlike the above-described embodiment, the upper member 12a and the lower member 12b are joined at the locations where the end portions of the respective members are bent and attached.

FIG. 3 is a top view schematically showing a part of the torsion beam suspension according to the present embodiment. It is an AA cross section of the torsion beam shown in FIG. It is a BB cross section of the torsion beam shown in FIG. It is CC cross section of the torsion beam shown in FIG. It is DD cross section of the torsion beam shown in FIG. It is a schematic diagram for demonstrating the bending moment when there exists input in a spring support part from a certain direction. It is a schematic diagram for demonstrating the bending moment when there exists an input to an absorber support part from a certain direction. It is sectional drawing which shows the state which welded the upper side member and lower side member in the torsion beam which concerns on other embodiment.

Explanation of symbols

  10 Torsion beam suspension, 12 Torsion beam, 12a Upper member, 12b Lower member, 14 Trailing arm, 16 Bush, 18 Unit bearing, 20 Spring, 22 Spring support, 24 Absorber, 26 Absorber support.

Claims (4)

A torsion beam whose longitudinal direction is the vehicle width direction of the vehicle;
A pair of plate-like trailing arms joined to both ends of the torsion beam and extending in the longitudinal direction of the vehicle;
The torsion beam has a spring support portion for supporting a spring for mitigating vibration from the road surface on the end side where the width of the vehicle in the front-rear direction of the torsion beam is wider than the center portion.
The torsion beam suspension according to claim 1, wherein the spring support portion is formed so that a cross section intersecting with a longitudinal direction of the vehicle becomes a closed cross section.   The torsion beam suspension according to claim 1, wherein the spring support portion has a closed cross section formed by the trailing arm and the torsion beam. The spring support portion is formed at the rear in the vehicle front-rear direction from the center portion of the torsion beam,
3. The torsion beam suspension according to claim 1, wherein the torsion beam is joined to the trailing arm from the spring support portion to the rear in the front-rear direction of the vehicle. The torsion beam has an absorber support part for supporting an absorber for damping vibration on the end side,
The torsion beam suspension according to any one of claims 1 to 3, wherein the absorber support portion is formed so that a cross section intersecting with a longitudinal direction of the vehicle becomes a closed cross section.

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