JP6035315B2 - Torsion beam for suspension - Google Patents

Description

  The present invention relates to a suspension torsion beam, and more particularly to a suspension torsion beam mounted on a vehicle such as a four-wheeled vehicle.

  In recent years, for suspension devices for vehicles such as four-wheeled vehicles, torsion beam suspensions having a small number of parts, a relatively simple structure, and excellent space efficiency have been widely adopted mainly for small displacement vehicles. Yes.

  Therefore, such a torsion beam type suspension is required to increase its strength and rigidity while improving its productivity.

  Under such circumstances, Patent Document 1 relates to a torsion beam type suspension, and in order to realize various stiffnesses that meet the specification requirements while saving materials, the lower edge of the front plate is intended to be adjusted. The front bending angle of the front reinforcing flange formed by bending forward from the front and the rear bending angle of the rear reinforcing flange formed by bending backward from the lower edge of the rear plate are disclosed.

JP2013-203200A

  However, according to the study of the present inventor, in the configuration of the torsion beam of Patent Document 1, the rigidity can be adjusted by bending the flange, but the adjustment width of the torsional rigidity is extremely large only by bending the flange. There is room for improvement in terms of widening the adjustment range of torsional rigidity to be applied to narrow and diverse vehicle specifications.

  The present invention has been made through the above-described studies, and provides a torsion beam for suspension capable of adjusting torsional rigidity with a high degree of freedom while ensuring good productivity and high strength with a simple configuration. With the goal.

  In order to achieve the above object, in the first aspect of the present invention, a trailing arm that supports a wheel is connected to the other end while one end is supported by the vehicle, and extends in the width direction of the vehicle. A torsion beam for suspension, wherein the torsion beam includes a front bulging wall that bulges so as to protrude forward of the vehicle body, a front vertical wall that hangs down from a lower end of the front bulging wall, and the front vertical beam A front wall having a front flange extending in the forward direction from the lower end of the wall; a rear bulging wall that bulges in a rearward direction of the vehicle body; and a rear vertical that hangs down from the lower end of the rear bulging wall A front wall having a rear flange extending in the rear direction from a lower end of the rear vertical wall, the rear wall being disposed on the rear side with respect to the front wall and facing the rear wall, The vertical wall is disposed in the rear direction from the front bulging wall. It said rear vertical wall has a structure which is disposed in the front direction than the rear bulging wall.

In addition to the first aspect, the present invention is located between the front bulging wall and the rear bulging wall, and protrudes upward from the vehicle body while the front bulging wall and the rear bulging. It is a second aspect to further include a protrusion that connects the upper ends of the walls.

  In addition to the first or second aspect, the present invention further includes a front reinforcing wall that hangs down from a front end of the front flange, and the rear wall extends from a rear end of the rear flange. It is a third aspect to further have a rear reinforcing wall that hangs down.

  In addition to the second or third aspect, the present invention provides a fourth aspect in which, at the end in the width direction, the protrusion has a widened protrusion having a wide width in the front-rear direction. To do.

  Moreover, this invention makes it 5th aspect to terminate the said widening protrusion part in the terminal part which exhibits a hook shape in planar view of the said vehicle body in addition to this 4th aspect.

  According to the configuration of the first aspect of the present invention, the suspension torsion beam is connected to the trailing arm that supports the wheel at the other end while the one end is supported by the vehicle and extends in the width direction of the vehicle. The torsion beam extends forward from the front bulging wall that bulges out in a forward direction of the vehicle body, the front vertical wall that hangs down from the lower end of the front bulging wall, and the lower end of the front vertical wall. A front wall having a front flange, a rear bulging wall that bulges in the rearward direction of the vehicle body, a rear vertical wall that hangs from the lower end of the rear bulging wall, and a rearward extension from the lower end of the rear vertical wall A rear wall that is disposed on the rear side of the front wall and that faces the front wall, the front vertical wall being disposed rearward of the front bulging wall, and By having a configuration in which the vertical wall is disposed in front of the rear bulge wall, Such in accordance with the vehicle specifications, with a simple configuration, it is possible to adjust the torsional rigidity with a high degree of freedom while ensuring good productivity and high strength.

  Further, according to the configuration of the second aspect of the present invention, the upper ends of the front bulge wall and the rear bulge wall are positioned between the front bulge wall and the rear bulge wall and protrude upward from the vehicle body. By further including a projecting portion for connecting the torsion beam, the torsion beam formability can be improved.

  According to the configuration of the third aspect of the present invention, the front wall further includes a front reinforcing wall that hangs down from the front end of the front flange, and the rear wall includes a rear reinforcing wall that hangs down from the rear end of the rear flange. In addition, the strength and rigidity of the torsion beam can be further improved.

  According to the configuration of the fourth aspect of the present invention, the torsion beam is placed on a welding jig or the like because the projecting portion has the widened projecting portion having a wide width in the front-rear direction at the end in the width direction. Therefore, the weldability can be improved with a simple configuration.

  Further, according to the configuration of the fifth aspect of the present invention, the widening protruding portion terminates at a terminal portion that exhibits a hook shape in a plan view of the vehicle body, whereby a sudden shape change of the longitudinal sectional shape in the width direction of the vehicle body is achieved. Therefore, the weldability can be improved while relaxing the stress concentration at the part where the shape has changed.

It is a top view of the torsion beam applied to the suspension of the vehicle in the embodiment of the present invention. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. FIG. 2 is a partially enlarged plan view of FIG. 1.

  Hereinafter, the torsion beam applied to the vehicle suspension in the embodiment of the present invention will be described in detail with reference to FIGS. 1 to 4 as appropriate. In the figure, the x-axis, y-axis, and z-axis form a three-axis orthogonal coordinate system. The positive direction of the x axis is the front direction of the vehicle body, the positive direction of the y axis is the left direction of the vehicle body, and the positive direction of the z axis is the upward direction of the vehicle body. In addition, the x-axis direction may be referred to as the longitudinal direction, and the y-axis direction may be referred to as the width direction.

  FIG. 1 is a plan view of a torsion beam applied to a vehicle suspension in the present embodiment. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 3 is a cross-sectional view taken along the line BB in FIG. FIG. 4 is a partially enlarged plan view of FIG.

  First, an overall configuration of a torsion beam applied to a vehicle suspension in the present embodiment will be described in detail with reference to FIG.

  As shown in FIG. 1, the torsion beam 10 is applied to a suspension of a vehicle such as a four-wheel automobile (not shown), and a trailing arm TA is attached to both ends in the width direction. The trailing arm TA is attached to a vehicle body such as a rear side frame while supporting the wheels.

  Specifically, the torsion beam 10 is a plate member made of a metal plate such as a steel plate having an upwardly convex shape, and extends in the width direction and has a pair of left and right trailing arms at both ends in the width direction. TA is connected.

  Each of the pair of trailing arms TA is a substantially cylindrical member typically made of a metal pipe member such as a steel pipe, and is fixed by being welded to the torsion beam 10 by arc welding or the like. It is. The pair of trailing arms TA may be welded in such a manner that a part of each of the trailing arms TA is covered with the both ends of the torsion beam 10 in the width direction, and each of the trailing arms TA is attached to both ends of the torsion beam 10 in the width direction. You may weld in the aspect pinched | interposed from the up-down direction in part.

  Next, the configuration of the torsion beam 10 will be described in more detail with reference to FIGS. 2 to 4 in addition to FIG.

  FIG. 2 is a longitudinal section taken along a plane parallel to the xz plane at the center in the width direction of the torsion beam 10 and a longitudinal section taken along a plane parallel to the xz plane at the left end in the width direction of the torsion beam 10. As shown in FIG. 3, the torsion beam 10 includes a front bulging wall 11 that bulges so as to protrude forward, a front vertical wall 12 that hangs down from the lower end of the front bulging wall 11, and a front vertical wall 12. A front wall 14 having a front flange 13 extending forward from the lower end, a rear bulging wall 15 bulging so as to protrude rearward, and a rear vertical wall 16 depending from the lower end of the rear bulging wall 15; And a rear wall 18 having a rear flange 17 extending rearward from the lower end of the rear vertical wall 16. The torsion beam 10 has a symmetrical shape with respect to the central portion in the width direction, and the front wall 14 and the rear wall 18 are disposed to face each other in the front-rear direction.

  In such a vertical cross section, the front wall 14 has a so-called inverse shape in which the front vertical wall 12 is located in the rearward direction from the bulging front end portion of the front bulging wall 11, and the rear wall 18 It has a so-called inverse shape that is located in front of the bulging rear end portion of the bulging wall 15.

  The front bulging wall 11 and the rear bulging wall 15 constitute a main strength member of the torsion beam 10 and preferably have an arcuate vertical cross section from the viewpoint of ensuring a large vertical cross section of the torsion beam 10.

  The front vertical wall 12 and the rear vertical wall 16 function as a torsional rigidity adjusting wall that can adjust the torsional rigidity of the torsion beam 10 by adjusting the respective positions back and forth.

  Here, in such a longitudinal section, from the viewpoint that the torsional rigidity of the torsion beam 10 can be accurately adjusted, the front vertical wall 12 and the rear vertical wall 16 are straight walls that are easy to accurately define their shapes by press molding. It is preferable that Further, in order to accurately define the shapes of the front vertical wall 12 and the rear vertical wall 16 by press molding, when the front vertical wall 12 and the rear vertical wall 16 are vertical straight walls, respectively, The amount of anteroposterior direction in which the wall 12 is recessed in the rearward direction from the bulging front end portion of the front bulging wall 11, and the rear vertical wall 16 in the forward direction from the bulging rear end portion of the rear bulging wall 15 It is more preferable to set the amount of the fore-and-aft direction in which the front vertical wall 12 and the rear vertical wall 16 are inclined straight walls, respectively. More preferably, the magnitude of the rearward tilt angle that tilts backward while drooping and the magnitude of the forward tilt angle that tilts forward while the rear vertical wall 16 hangs down are set equal. However, when the increase in the number of press molding steps is allowed, the front vertical wall 12 and the rear vertical wall 16 may each be a curved wall. Further, when it is allowed to adjust the torsional rigidity of the torsion beam 10, the positional characteristics such as the amount of inclination of the front vertical wall 12 with respect to the front bulging wall 11 and the inclination angle, and the rear bulging wall 15 may be different from the positional properties such as the amount of the rear vertical wall 16 with respect to 15 and the inclination angle, and only one of the front vertical wall 12 and the rear vertical wall 16 may have an inverse shape. .

  Further, from the viewpoint of adjusting the torsional rigidity while sufficiently securing the strength of the torsion beam 10, the vertical length L1 between the upper end and the lower end of the front vertical wall 12 is between the upper end and the lower end of the front bulging wall 11. The vertical length L3 between the upper end and the lower end of the rear vertical wall 16 is preferably equal to or smaller than the vertical length L4 between the upper end and the lower end of the rear bulging wall 15. It is preferable that

  Further, from the viewpoint of increasing the bonding strength between the torsion beam 10 and the pair of trailing arms TA, the front vertical wall 12 gradually advances forward from the center of the torsion beam 10 toward both ends in the width direction. The rear vertical wall 16 continues to the lower end of the front bulging wall 11 while the rear vertical wall 16 continues to the position where the rear vertical wall 16 gently moves backward. It is preferable that the torsion beam 10 has a substantially U-shaped cross section at both ends in the width direction by connecting to the lower end of 16. However, in the case where a sufficient bonding strength between the torsion beam 10 and the pair of trailing arms TA can be secured, both or one of the front vertical wall 12 and the rear vertical wall 16 at the both end portions in the width direction of the torsion beam 10 is inverse. It may have a shape.

  The front flange 13 and the rear flange 17 are typically straight walls in the longitudinal section. From the viewpoint of suppressing an increase in the weight of the torsion beam 10, the length L5 in the front-rear direction between the rear end and the front end of the front flange 13 is not more than the length L2 in the vertical direction between the upper end and the lower end of the front bulging wall 11. It is preferable that the length L6 in the front-rear direction between the front end and the rear end of the rear flange 17 is preferably equal to or less than the length L4 in the vertical direction between the upper end and the lower end of the rear bulging wall 15.

  Further, the torsion beam 10 preferably further includes a front reinforcing wall 19 that hangs down from the front end of the front flange 13 and a rear reinforcing wall 20 that hangs down from the rear end of the rear flange 17 from the standpoint of enhancing the strength thereof. . At this time, from the viewpoint of suppressing an increase in the weight of the torsion beam 10, the vertical length L7 between the upper end and the lower end of the front reinforcing wall 19 is equal to or less than the length L5 between the rear end and the front end of the front flange 13 in the front-rear direction. The vertical length L8 between the upper end and the lower end of the rear reinforcing wall 20 is preferably equal to or smaller than the length L6 of the rear flange 17 between the front end and the rear end. The front reinforcing wall 19 and the rear reinforcing wall 20 may be any of a vertical straight wall, an inclined straight wall, and a curved wall.

  Further, the torsion beam 10 is located between the front bulging wall 11 and the rear bulging wall 15 in the front-rear direction from the standpoint of improving the press formability, and protrudes upward and the front bulging wall 11 and It is preferable to further include a protrusion 21 that connects the upper ends of the rear bulging walls 15. From the standpoint of improving the mountability of the torsion beam 10 on a welding jig or the like, the projecting portion 21 extends in the width direction in a plan view, and both end portions in the width direction have a wide width in the front-rear direction. Each of the protrusions 22 is preferably provided. From the standpoint of improving placement on a welding jig or the like while suppressing stress concentration in the torsion beam 10, it is preferable that the widened protrusion 22 terminates at a terminal portion that exhibits a hook shape in plan view.

  Further, from the viewpoint of increasing the bonding strength between the torsion beam 10 and the pair of trailing arms TA while improving the press formability of the torsion beam 10, the inverse shapes of the front vertical wall 12 and the rear vertical wall 16 are: It is preferable that they are respectively terminated at the widening protrusions 22 and are not provided on the left and right outside of the widening protrusions 22.

  In particular, as shown in an enlarged view in FIG. 4, the torsion beam 10 has a front flange 13, a front bulging wall 11, and a rear bulging wall at both ends in the width direction of the torsion beam 10 from the viewpoint of enhancing the strength. It is preferable to further include a bead 23 that is recessed in the front-rear direction. By providing such a bead 23 along the welded portion of the torsion beam 10 and the trailing arm TA, stress concentration on the welded portion can be suppressed. In addition, this bead 23 may be provided in a back flange, and when the front reinforcement wall 19 and the rear reinforcement wall 20 are provided, it may be provided in these.

  In the present invention, the type, shape, arrangement, number, and the like of the members are not limited to the above-described embodiment, and the gist of the invention is appropriately replaced such that the constituent elements are appropriately replaced with those having the same operational effects. Of course, it can be changed as appropriate without departing from the scope.

  As described above, the present invention can provide a torsion beam for suspension that can adjust torsional rigidity with a high degree of freedom while ensuring good productivity and high strength with a simple configuration. Therefore, it is expected to be widely applicable to the field of torsion beam suspensions of moving bodies such as vehicles because of its general-purpose universal character.

DESCRIPTION OF SYMBOLS 10 ... Torsion beam 11 ... Front bulging wall 12 ... Front vertical wall 13 ... Front flange 14 ... Front wall 15 ... Rear bulging wall 16 ... Rear vertical wall 17 ... Rear flange 18 ... Rear wall 19 ... Front reinforcement wall 20 ... Rear reinforcement Wall 21 ... Projection 22 ... Widening projection 23 ... Bead TA ... Trailing arm

Claims (5)

A suspension torsion beam extending in the width direction of the vehicle body while connecting a trailing arm that supports a wheel to the other end while one end side is supported by the vehicle body,
The torsion beam is
A front bulging wall that bulges out in a forward direction of the vehicle body, a front vertical wall that hangs from the lower end of the front bulging wall, and a front flange that extends in the forward direction from the lower end of the front vertical wall A front wall having
A rear bulging wall that bulges toward the rear of the vehicle body, a rear vertical wall that hangs from a lower end of the rear bulging wall, and a rear flange that extends rearward from the lower end of the rear vertical wall A rear wall disposed on the side of the rear direction with respect to the front wall and facing the rear wall;
With
The front vertical wall is disposed in the rearward direction with respect to the front bulging wall, and the rear vertical wall is disposed in the forward direction with respect to the rear bulging wall.   And a protrusion that is positioned between the front bulging wall and the rear bulging wall and connects the upper ends of the front bulging wall and the rear bulging wall while projecting upward from the vehicle body. The torsion beam for suspension as described in 1. The front wall further includes a front reinforcing wall depending from a front end of the front flange,
The suspension torsion beam according to claim 1, wherein the rear wall further includes a rear reinforcing wall depending from a rear end of the rear flange.   4. The suspension torsion beam according to claim 2, wherein, at the end in the width direction, the protrusion includes a widened protrusion having a wide width in the front-rear direction.   5. The suspension torsion beam according to claim 4, wherein the widening protrusion portion terminates at a terminal portion having a hook shape in a plan view of the vehicle body.

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