JP2006001334A - Torsion beam type suspension device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a torsion beam type suspension device capable of effectively utilizing a space under a vehicle body by using a torsion bar. <P>SOLUTION: Trailing arms 10L, 10R are turnable assembled around axes of first torsion bars 12L, 12R via bushes 14L, 14R at each front end. A torsion beam 11 is formed in a substantially U-shaped section, and integrally connected to front ends of the trailing arms 10L, 10R at both ends 11a, 11b. The first torsion bars 12L, 12R extend along an inner peripheral surface of the torsion beam 11, and are fixed to a vehicle body BD via brackets 17L, 17R at each outer end, and coupled with each other in a non-rotational manner by a bracket 16 at each inner end. Second torsion bars 13L, 13R are fixed to rear ends of the trailing arms 10L, 10R at each outer end, and coupled with each other in a non-rotational manner by the bracket 16 at each inner end. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a torsion beam suspension device including a pair of left and right trailing arms and a torsion beam.

Conventionally, as this type of torsion beam suspension device, for example, as described in Patent Document 1 below, it extends in the front-rear direction of the vehicle and rotates around the substantially horizontal axis at the vehicle body at each front end. A pair of left and right trailing arms assembled to each other at the rear end, and a pair of left and right trailing arms extending in the vehicle width direction and connected to the pair of left and right trailing arms at both ends. One with a torsion beam is known. In this suspension device, a coil spring is generally provided between each trailing arm and a vehicle body side member represented by, for example, a side member for the purpose of suppressing a change in the posture of the vehicle or alleviating an impact from the road surface. Is intervening.
JP 2000-94917 A

  In the conventional torsion beam type suspension device, since it is necessary to dispose the coil spring below the vehicle body side member, there is no room in the space below the vehicle body side member. Moreover, it is necessary to lengthen the length of the coil spring to some extent so that the coil spring does not contact between the lines when the wheel is fully bound. Further, since the lower end of the coil spring needs to be raised to some extent, the upper end of the coil spring tends to be higher. Therefore, the installation height of the vehicle body side member that supports the upper end of the coil spring increases, and there is a problem that the shape of the vehicle body side member is restricted.

  The present invention has been made in order to cope with the above problem, and its purpose is to provide a spring member in place of the coil spring so that the space below the vehicle body side member can be used effectively. An object of the present invention is to provide a torsion beam suspension device capable of improving the degree of freedom of the configuration of the vehicle body side member.

  In order to achieve the above object, the present invention is characterized by extending in the front-rear direction of the vehicle and assembled to the vehicle body at each front end portion so as to be rotatable about a substantially horizontal axis, and at the rear end portions at the left and right rear sides. In a torsion beam suspension apparatus comprising a pair of left and right trailing arms each assembled with a wheel, and a torsion beam extending in the width direction of the vehicle and connected to the pair of left and right trailing arms at both ends, A first torsion bar extending in the width direction and fixed to the vehicle body at both ends, and a second torsion bar extending in the width direction of the vehicle and fixed to the pair of left and right trailing arms at both ends. A torsion bar, and the first torsion bar and the second torsion bar are integrally connected so as to be unrotatable around the axis at each intermediate portion. Lies in the fact.

  When the wheel is displaced in the vertical direction by an input from the road surface, the trailing arm rotates in the vertical direction about a substantially horizontal axis. As the trailing arm rotates, the second torsion bar is twisted about the axis. At this time, the first torsion bar is also twisted by the torsional torque acting on the portion to which the first torsion bar is connected. For this reason, the input from a road surface can be relieve | moderated by the twist of a 1st and 2nd torsion bar. Thus, by using the first and second torsion bars that do not require a space below the vehicle body side member, the same function as the coil spring can be achieved. Therefore, the space below the vehicle body side member can be used effectively, and the degree of freedom of the configuration of the vehicle body side member can be improved. In addition, if the first and second torsion bars are used, the entire length of the torsion bar can be set long, so that the spring constant can be reduced and the impact from the road surface can be easily absorbed. In addition, when the left and right wheels are displaced in the opposite phase (upside down direction), in addition to the torsion beam torsion, the second torsion bar is also twisted in the up and down direction. It is also possible to improve running stability by reducing the amount of travel.

  Another feature of the present invention is that the torsion beam is formed by crushing an axial intermediate portion of a cylindrical pipe to form a substantially U-shaped or V-shaped cross section of the intermediate portion. The first torsion bar extends along the inner peripheral surface on the side where the torsion beam is crushed so that the axis thereof is positioned on substantially the same axis as the axis of the torsion beam. It exists in the structure which supports an arm rotatably about a coaxial line.

  According to this, the first torsion bar can be provided by effectively using the space in which the torsion beam is extended. Therefore, there is an advantage that it is not necessary to secure a new space for the first torsion bar.

a. First Embodiment Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the entire torsion beam suspension device according to the first embodiment. This torsion beam suspension device includes a pair of left and right trailing arms 10L and 10R, a torsion beam 11, and a pair of left and right first torsion bars 12L. , 12R and second torsion bars 13L, 13R.

  The pair of left and right trailing arms 10L and 10R are configured by bending a long pipe having a rectangular cross section. The trailing arms 10L and 10R are extended in the front-rear direction of the vehicle, and are assembled so as to be rotatable around the axes of first torsion bars 12L and 12R, which will be described later, via bushes 14L and 14R at the respective front end portions. In addition, left and right rear wheels (not shown) are assembled via axles 15L and 15R at rear end portions extending from the front end portions to the rear and downward of the vehicle.

  In the torsion beam 11, both end portions 11a and 11b are formed in a cylindrical shape, and the axial direction intermediate portion 11c is crushed to form a substantially U-shaped cross section of the intermediate portion 11c. The torsion beam 11 is extended in the width direction of the vehicle so that the inner peripheral surface formed by crushing faces the front of the vehicle, and the front end portions of the trailing arms 10L and 10R at both ends 11a and 11b, respectively. For example, they are integrally connected by welding.

  The pair of left and right first torsion bars 12L and 12R have serrations formed by a plurality of serrated teeth (not shown) on the outer peripheral surface of each inner end, and can be fitted to the teeth. The boss portions 16a of the bracket 16 having tooth portions on the inner peripheral surface are serrated and coupled to each other so as not to rotate relative to each other.

  Further, as shown in FIGS. 2 and 3, the first torsion bars 12L and 12R are provided on the inner peripheral surface on the side where the torsion beam 11 is crushed so that the respective axes are located on substantially the same axis as the axis of the torsion beam 11. Is extended horizontally in the width direction of the vehicle. The first torsion bars 12L and 12R have outer end portions penetrating both end portions 11a and 11b of the torsion beam 11 and bushes 14L and 14R, respectively, and brackets 17L and 17R outside the trailing arms 10L and 10R. Are respectively fixed to the vehicle body BD. The first torsion bars 12L and 12R may be fixed to a vehicle body side member represented by a side member at each outer end portion, or may be directly fixed to the vehicle body BD.

  The pair of left and right second torsion bars 13L and 13R are formed of bar members that are curved in an arc shape, are extended in the width direction of the vehicle, and are rearward of the trailing arms 10L and 10R at the respective outer ends. Each is fixed to the end.

  Similarly to the first torsion bars 12L and 12R, the second torsion bars 13L and 13R respectively have serrations composed of a plurality of serrated teeth (not shown) on the outer peripheral surface of each inner end. Thus, the boss portions 16b of the bracket 16 having tooth portions that can be fitted to the tooth portions on the inner peripheral surface are serration-coupled so as not to rotate relative to each other. In this state, the second torsion bars 13L and 13R are set with a predetermined twist angle around each axis in advance, and a predetermined mounting load is set with respect to the axles 15L and 15R, as in the case of using a coil spring. Has been.

  The bracket 16 is formed in a substantially H shape, and the boss portions 16a and 16b are integrally formed by the connection portion 16c. A long hole 11c1 is formed on the rear side of the vehicle in the axial direction intermediate portion 11c of the torsion beam 11, and the connecting portion 16c of the bracket 16 extends from the inside of the torsion beam 11 to the outside through the long hole 11c1. ing. As a result, the bracket 16 rotates about the axis of the first torsion bars 12L and 12R as the first torsion bars 12L and 12R are twisted.

  According to the embodiment configured as described above, for example, when the axles 15L and 15R are displaced upward or downward by the input from the road surface, the trailing arms 10L and 10R are axial lines of the first torsion bars 12L and 12R. Rotate up or down around. As the trailing arms 10L and 10R rotate, the second torsion bars 13L and 13R are twisted around the axis of the end portion on the boss portion 16b side of the bracket 16, and the boss portion 16b is displaced upward or downward. And At this time, the first torsion bars 12L and 12R are also twisted when the force acting on the boss portion 16b and the torsion torque corresponding to the length of the connecting portion 16c act on the boss portion 16a. For this reason, the input from the road surface can be mitigated by the torsion of the first torsion bars 12L, 12R and the second torsion bars 13L, 13R.

  Further, for example, when the axles 15L and 15R are displaced in the reverse phase (upward and downward direction) by the input from the road surface, the torsion beam 11 is twisted as the trailing arms 10L and 10R are rotated in the reverse direction. At the same time, the second torsion bars 13L and 13R are also twisted in opposite directions around the axis of the end portion on the boss portion 16b side. For this reason, the torsional rigidity can be set high, and the running stability can be improved by reducing the roll of the vehicle body.

  Thus, by using the first and second torsion bars 12L, 12R, 13L, and 13R that do not require a space below the vehicle body BD, a function equivalent to that of the coil spring can be achieved. Therefore, the space below the vehicle body BD can be used effectively, and the degree of freedom of the configuration of the vehicle body side member such as the side member can be improved. In addition, if the first and second torsion bars 12L, 12R, 13L, and 13R are used, the entire length of the torsion bar can be set long, so that the spring constant can be reduced and the impact from the road surface can be easily absorbed. Is possible. Further, since the first torsion bars 12L and 12R are extended along the inner peripheral surface on the side where the torsion beam 11 is crushed, it is necessary to secure a new space for the first torsion bars 12L and 12R. There is also an advantage that there is no.

  In this embodiment, the torsion beam 11 is extended in the width direction of the vehicle so that the inner peripheral surface formed by crushing faces the front of the vehicle. You may make it extend in the width direction of a vehicle so that it may face back or the downward direction. In this case, it is not necessary to form the long hole 11c1 for the bracket 16 in the axial direction intermediate portion 11c of the torsion beam 11 if the inner peripheral surface faces the rear of the vehicle.

b. Second Embodiment Next, a second embodiment of the present invention will be described. In the description of the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the torsion beam suspension device according to the second embodiment, as shown in FIG. 4, the first torsion bars 12L and 12R are fixed to the vehicle body BD by side frames 21L and 21R at the respective outer ends. The side frames 21L and 21R extend in the front-rear direction of the vehicle, and are assembled to the vehicle body BD via the bushes 22L and 22R at the front ends and the bushes 23L and 23R at the rear ends. The bushes 22L, 23L, 22R, and 23R can be displaced by a predetermined amount in each axial direction and each radial direction by elastic deformation of rubber (not shown).

  The bracket 16 includes boss portions 16a and 16b as in the first embodiment. However, unlike the first embodiment, the elongated hole 11c1 is not formed in the axial direction intermediate portion 11c of the torsion beam 11, and the bracket 16 replaces the connecting portion 16c that integrally connects the boss portions 16a and 16b. In addition, for example, a first connection portion 16d that fixes the boss portion 16a to the inner peripheral surface of the torsion beam 11 by welding and a second connection portion 16e that fixes the boss portion 16b to the outer peripheral surface of the torsion beam 11 are provided. Yes.

  Also in the second embodiment, as in the first embodiment, when the axles 15L, 15R are displaced upward or downward by the input from the road surface, the second torsion bars 13L, 13R are It is twisted around the axis of the boss 16b side end. In this case, the torsion beam 11 and the trailing arms 10L and 10R are rotated around the axes of the bushes 14L and 14R by an upward or downward force acting on the boss portion 16b and the second connection portion 16e. As the first connection portion 16d and the boss portion 16a rotate according to the rotation of the torsion beam 11, the first torsion bars 12L and 12R are twisted. For this reason, the input from the road surface can be mitigated by the torsion of the first torsion bars 12L, 12R and the second torsion bars 13L, 13R.

  Further, for example, when the axles 15L and 15R are displaced in the reverse phase (upward and downward direction) by the input from the road surface, the torsion beam 11 is twisted and the second torsion bars 13L and 13L, as in the first embodiment. 13R is twisted in directions opposite to each other around the axis of the end portion on the boss portion 16b side. Therefore, also according to the second embodiment, the torsional rigidity can be set high, and it is possible to reduce the roll of the vehicle body and improve the running stability.

  In the second embodiment as well, the space below the vehicle body BD can be used effectively as in the first embodiment. Further, the spring constant of the torsion bar as a whole can be reduced, and the impact from the road surface can be easily absorbed. Further, there is an advantage that it is not necessary to secure a new space for the first torsion bars 12L and 12R.

  Further, according to the second embodiment, by using the side frames 21L, 21R assembled to the vehicle body BD via the bushes 22L, 23L, 22R, 23R, in addition to the above-described effects, harshness, that is, a paved road It is possible to reduce shocking vibrations that occur when passing through seams, etc., tire noise that occurs due to road noise, that is, tread patterns, etc., and it is also possible to improve compliance steer due to lateral force .

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the object of the present invention.

  For example, in each of the above embodiments, the pair of left and right first torsion bars 12L and 12R and the second torsion bars 13L and 13R are serrated and connected to each other by the boss portions 16a and 16b of the bracket 16 so as not to rotate relative to each other. By doing so, each one functions as a torsion bar. Thus, the first torsion bars 12L and 12R and the second torsion bars 13L and 13R could be easily assembled to the suspension device. However, the first and second torsion bars are each constituted by a single bar, and the torsion bars are integrally connected so as not to rotate around the axis at each intermediate portion. May be.

1 is a perspective view showing a torsion beam suspension device according to a first embodiment of the present invention. It is 2-2 sectional drawing of FIG. FIG. 3 is a 3-3 cross-sectional view of FIG. 1. It is a perspective view which shows the torsion beam type suspension apparatus which concerns on 2nd Embodiment by this invention. FIG. 5 is a sectional view taken along line 5-5 in FIG. 4.

Explanation of symbols

BD ... body, 10L, 10R ... trailing arm, 11 ... torsion beam, 12L, 12R ... first torsion bar, 13L, 13R ... second torsion bar, 16 ... bracket

Claims (2)

A pair of left and right trailing arms that extend in the front-rear direction of the vehicle and are assembled to the vehicle body at each front end so as to be rotatable about a substantially horizontal axis, and the left and right rear wheels are assembled to each rear end; A torsion beam suspension device comprising a torsion beam extending in the width direction of the vehicle and connected to the pair of left and right trailing arms at both ends,
A first torsion bar extending in the width direction of the vehicle and fixed to the vehicle body at both ends;
A second torsion bar extending in the width direction of the vehicle and fixed to the pair of left and right trailing arms at both ends,
A torsion beam suspension device, wherein the first torsion bar and the second torsion bar are integrally connected so as to be unrotatable about an axis at each intermediate portion. In the torsion beam suspension device according to claim 1,
The torsion beam is formed by crushing an intermediate portion in the axial direction of a cylindrical pipe to form a cross section of the intermediate portion in a substantially U shape or a substantially V shape,
The first torsion bar extends along the inner peripheral surface on the side where the torsion beam is crushed so that the axis thereof is positioned on substantially the same axis as the axis of the torsion beam. A torsion beam suspension device configured to support an arm rotatably about a coaxial line.

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