JPH07257126A - Vehicle suspension - Google Patents

Abstract

PURPOSE:To satisfy the ground clearance and the height of a seating position of a rear seat, and to enhance the anti-dive ability and the anti-lift ability. CONSTITUTION:A wheel support member 2 is connected at the outer end part of a transverse link 2 which extends widthwise of a vehicle, from a suspension member 1, and which is rigidly connected at its upper surface to the rear end part 5a of a radius rod 5 that extends forward, longitudinally to the vehicle body. The radius rod 5 is planar and resilient, and is laid with its thicknesswise direction being vertical so that it is vertically and resiliently deformable. Further, the front end of the radius rod 5 is fixed to the vehicle body side by means of a tension rod 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle suspension provided with a radius rod and a trailing arm extending in the longitudinal direction of a vehicle body.

[0002]

2. Description of the Related Art As a conventional vehicle suspension equipped with a radius rod, for example, Japanese Patent Laid-Open No. 62-2512.
18 and Japanese Patent Laid-Open No. 4-237681. The vehicle suspension described in Japanese Patent Laid-Open No. 62-251218 is a parallel link type suspension, and a pair of parallel links are provided from both left and right ends of a suspension member extending in the vehicle width direction. The parallel links extend outward in the vehicle width direction, and the outer ends of the parallel links are vertically swingably connected to the left and right axles that form wheel-side members.

Each of the axles rotatably supports the wheels. A radius rod having a rear end connected to the axle so as to be vertically swingable extends forward in the vehicle body front-rear direction, and a front end thereof is vertically swingably connected to a vehicle body-side member. A suspension strut extending in the vertical direction is provided between the axle and the vehicle body-side member.

Further, in the vehicle suspension disclosed in Japanese Patent Laid-Open No. 4-237681, a transverse member extends in the vehicle width direction, and side support members are provided at the left and right ends of the transverse member, respectively. A suspension member (member on the vehicle body side) that is extended in the direction, and is elastically supported on the vehicle body side through insulators attached to both end portions of the side members of the suspension member in the vehicle front-rear direction. There is.

Wheel-side members are provided at the left and right ends of the transverse member, respectively. The wheel side member includes a knuckle for fixing the lower end portion of the suspension strut, a spindle provided on the wheel side of the knuckle and coaxial with the wheel, and rotatably connected to the outer periphery of the spindle to connect the wheel to the outside thereof. It consists of a hub that is fixed to.

The rear end of the radius rod is swingably attached to the wheel member. The radius rod extends substantially forward in the front-rear direction of the vehicle body, and its front end portion is swingably attached to the front end portion side of the side support member.
Further, as a conventional vehicle suspension equipped with a trailing arm type suspension arm, for example,
There is a semi-trailing type rear suspension as shown in FIG.

This is because a pair of left and right suspension arms 61, which are integrated with a wheel-side member 60 that rotatably supports the left and right wheels, extend forward and backward in the vehicle body, and the pair of suspension arms 61 The front end portions 61b are respectively attached to suspension members 62 extending in the vehicle width direction via rubber bushes in a state of being pivotally supported so as to be vertically swingable. As a result, the suspension arm 61
It is possible to swing up and down around the arm rotation shaft on the vehicle body side attachment part side.

In FIG. 15, 63 is a shock absorber, 64 is a differential gear, 65 is a drive shaft, and 66 is a stabilizer.

[0009]

In the vehicle suspension as described above, the height of the radius rod or suspension arm extending in the longitudinal direction of the vehicle body on the vehicle body side is determined by the height of the anti-dive performance of the front suspension during braking. It has a structure that determines the anti-lift performance of the rear suspension.

Considering now the pitching moment M _f around the vehicle body weight center point during braking on the front side, FIG.
With reference to, it is expressed by the following formula. M _f = B _f × a _f = B _f × (Hg−L _f × tan ζ _f ) ... (1) Here, in FIG. 16, G1 is the vehicle center of gravity point, Hg is the height of the vehicle center of gravity point, B _f is the braking force input to the wheel, L _f
Is the distance in the vehicle body front-rear direction between the ground contact point of the wheel and the center of gravity of the vehicle, S4 is the trajectory of the ground contact point relative to the stroke of the front suspension in side view, and H1 is the trajectory S4.
The normal line at the ground contact point, and ζ _f indicate the upward inclination of the above normal line with respect to the ground plane.

As can be seen from the equation (1), the tilt angle ζ
_The larger _f is, the smaller the pitching moment M _f is. That is, in order to reduce the nose dive during braking, it is necessary to increase the inclination ζ _f . At this time,
The contact point locus S4 during the stroke of the suspension, which determines the inclination ζ _f , is regulated by the radius rod 70, as shown in FIG.
It is determined by the vertical swing around the vehicle body side attachment point 70b.

In order to increase the inclination ζ _f , it is necessary to dispose the radius rod 70 so that the ground contact point at the time of bouncing moves toward the front of the vehicle. As shown in FIG. 18B, it is better to set the vehicle body side mounting point 70b of the radius rod 70 by lowering it. Therefore, in order to reduce the nose dive during braking as described above, it is necessary to lower the mounting point of the radius rod on the vehicle body side, but there is a limit from the minimum ground clearance.

Further, the vehicle weight center point at the time of braking on the rear side
Pitching moment M around_rConsidering Fig. 19,
For reference, it is expressed by the following formula. M_r= B_r× a_r= B_rX (Hg-L_r× tan slope ζ_r・ ・ ・ (2) Here, in FIG. 19, G2 is the center of gravity of the vehicle, and Hg is the vehicle.
Height of both centers of gravity, B_r Is the braking force input to the wheel, L_r
Is the distance between the ground contact point of the wheel and the center of gravity of the vehicle in the vehicle longitudinal direction.
Away, S5 is the contact for the stroke of the rear suspension.
A locus in a side view of the point, H2, is a contact point of the locus S5.
Normal at point, slope ζ_rIs the normal to the ground plane
Shows the upward tilt of.

As can be seen from the equation (2), the slope ζ _r
Becomes larger, the pitching moment M _r becomes smaller. That is, in order to reduce the tail lift during braking,
It is necessary to increase the slope ζ _r . At this time, the contact point locus S5 during the stroke of the suspension that determines the inclination ζ _r is, as shown in FIG. 20, a radius rod or suspension arm 72 extending in the vehicle front-rear direction.
And is determined by the vertical swing of the radius rod or suspension arm 72 around the vehicle body side attachment point 72b.

In order to increase the inclination ζ _r , it is necessary to dispose the radius rod or the suspension arm 72 so that the ground contact point at the time of bouncing moves to the rear of the vehicle. For this purpose, FIG. ) Than Figure 2
It is better to raise and set the vehicle body side attachment point 72b of the radius rod or the suspension arm 72 as shown in 1 (a).

Therefore, in order to reduce the tail lift during braking as described above, it is necessary to raise the vehicle body side mounting point of the radius rod or the suspension arm. However, as shown in FIG. 22, there is a seating position C of the rear seat 73 above the vehicle body side attachment point 72b of the radius rod or the suspension arm 72, and the seating position C is regulated by the height of the seating position C. At this time, in general, the seating position C of the rear seat 73 is desired to be set low, so that the radius rod or the suspension arm 7 is set.
There is a limit to the height of the point 72b on the vehicle body side mounting portion 72b.

As described above, in the conventional vehicle suspension, due to the vehicle layout requirements such as the minimum ground height and the height of the seating position of the rear seat, the radius rods extending in the vehicle front-rear direction and the attachment points of the suspension arms on the vehicle body side are selected. There was a limit to the setting of the anti-pitch performance improvement that restrains the nose dive and tail lift during braking due to height restrictions.

The present invention has been made by paying attention to the problems as described above, and satisfies the vehicle layout requirements such as the minimum ground clearance and the height of the seating position of the rear seat, while the nose at the time of braking. The purpose is to suppress dive tail lift and improve anti-dive performance and anti-lift performance.

[0019]

In order to achieve the above object, the vehicle suspension according to claim 1,
In a front suspension including a radius rod that extends in the vehicle body front-rear direction and has one end connected to a wheel side member and the other end connected to a vehicle body side member, the radius rod has a front end rigidly connected to the vehicle body side member. It consists of an elastic body that is attached and elastically deformable in the vertical direction of the vehicle body,
It is characterized in that, when the vehicle is in the standard posture, it is initially set in a state of being bent downward from a straight line connecting both end mounting portions.

According to the second aspect of the present invention, there is provided a rear suspension having a radius rod extending in the vehicle front-rear direction and having one end connected to the wheel side member and the other end connected to the vehicle body side member. In the above, the radius rod is composed of an elastic body whose front end is rigidly attached to the vehicle body side member and is elastically deformable in the vertical direction of the vehicle body. It is characterized by being initially set in a bent state.

Further, in the vehicle suspension described in claim 3, a trailing arm type suspension extending in the longitudinal direction of the vehicle body and having one end connected to the wheel side member and the other end connected to the vehicle body side member. In a rear suspension including an arm, the suspension arm and a vehicle body-side member are connected via an elastic member made of an elastic body extending in the vehicle front-rear direction and elastically deformable in the vehicle up-down direction. Is rigidly connected to the suspension arm and the vehicle body side member respectively, and is initially set in a state of being bent above a straight line connecting both end mounting portions thereof.

At this time, for example, as described in claim 4, the vehicle body side mounting portion of the radius rod or the elastic member made of the elastic body is provided at a predetermined angle in the vertical direction with respect to the straight line connecting the both end mounting portions. It is preferable that the radius rod or the elastic member made of the elastic body is bent upward or downward by being attached to the member on the vehicle body side while being inclined.

[0023]

In the vehicle suspension described in claim 1, the radius rod has a cantilever structure in which the radius rod is made of an elastic member and supported on the vehicle body side. Then, the radius rod follows the vertical stroke of the suspension and bends in the vertical direction with the vehicle-body-side mounting portion as a fulcrum.

At this time, since the radius rod is bent in a downwardly convex state in the initial state, the radius rod is further bent at the time of bouncing, so that the space between the wheel side member and the vehicle body side member connected by the radius rod is reduced. Compared with the case of connecting with a radius rod composed of such a rigid body, the wheel-side mounting portion moves upward while being displaced forward in the vehicle front-rear direction.

On the other hand, at the time of rebound, the radius rod moves downward while the amount of deflection decreases from the bent state, that is, the center line of the radius rod changes to a linear direction, and therefore the wheels connected by the radius rod. Compared with the case where the side member and the vehicle body side member are connected by a conventional radius rod made of a rigid body, the wheel side attachment portion of the radius rod moves downward while being displaced rearward in the vehicle front-rear direction.

Therefore, even if the height of the mounting point of the radius rod on the vehicle body side is set to the same height position as that of the conventional radius rod made of a rigid body, the contact point of the grounding point due to the vertical stroke of the suspension viewed from the side of the vehicle The inclination of the normal line at the ground contact point with respect to the locus to the ground becomes large. In order to realize this with a conventional radius rod made of a rigid body, it is necessary to offset the end portion of the radius rod on the vehicle body side downward.

In order to keep the radius rod bent downward, for example, as described in claim 4, the vehicle body side mounting surface is rearward of the vehicle with respect to a line connecting both end mounting points. This can be achieved by tilting downwards and fixing. In addition, in the vehicle suspension described in claim 2, the radius rod has a cantilever structure in which the vehicle body side is supported by an elastic member. Then, the radius rod follows the vertical stroke of the suspension and bends in the vertical direction with the vehicle-body-side mounting portion as a fulcrum.

At this time, since the radius rod is bent upward in the initial state, it is further bent at the time of rebound, and the space between the wheel side member and the vehicle body side member connected by the radius rod is the same as in the conventional case. Compared with the case where the rigid rods are connected by a radius rod, the wheel-side mounting portion moves downward while being displaced forward in the vehicle body front-rear direction.

On the other hand, at the time of bouncing, the radius rod moves upward while its bending amount decreases from the bent state, that is, the center line changes to a linear direction, so that the radius rod is connected to the wheel-side member connected by the radius rod. Compared with the conventional case where a radius rod made of a rigid body is connected to the member on the vehicle body side, the wheel side attachment portion of the radius rod moves upward while being displaced rearward in the vehicle front-rear direction.

Therefore, even if the height of the mounting point of the radius rod on the vehicle body side is set at the same position as that of the conventional radius rod made of a rigid body, the locus of the ground contact point due to the vertical stroke of the suspension viewed from the side of the vehicle The inclination of the normal line at the ground contact point with respect to the ground becomes large. In order to realize this with a conventional radius rod made of a rigid body, it is necessary to offset the end portion of the radius rod on the vehicle body side upward.

In order to keep the radius rod bent upwards, for example, as described in claim 4, the vehicle body side mounting surface is rearward of the vehicle with respect to a line connecting both end mounting points. This can be achieved by tilting it upwards and fixing it. Further, in the vehicle suspension described in claim 3, since the vehicle body side mounting portion of the suspension arm extending in the vehicle body front-rear direction is connected via the elastic member extending in the vehicle body front-rear direction, the suspension stroke follows the vertical stroke of the suspension. As the elastic member bends in the vertical direction, the suspension arm swings in the vertical direction around the vehicle body side mounting portion side.

At this time, since the elastic member is initially set so as to be bent upward, the suspension arm side attachment point of the elastic member is further deflected at the time of rebound, and the wheel side attachment portion is in the vehicle longitudinal direction. It moves downward while displacing forward. On the other hand, at the time of bouncing, the elastic member is displaced upward while changing from a bent state to a direction in which the amount of bending decreases, that is, the center line becomes linear.

At this time, conventionally, during the suspension stroke, the attachment point of the suspension arm on the vehicle body side oscillates up and down around the vehicle body attachment axis without much displacement in the longitudinal direction of the vehicle body.
According to the present invention, as described above, the vehicle body side portion of the suspension arm moves downward while displacing forward in the vehicle front-rear direction during rebound, and moves upward while displacing rearward in the vehicle front-rear direction during bouncing. The wheel-side part of the arm moves downward while displacing forward in the vehicle front-rear direction during rebound, and moves backward in the vehicle front-rear direction during bounding, as compared to the case where the vehicle body-side mounting point of the suspension arm is pivoted as in the past. Move upward while displacing to.

Therefore, even if the height of the attachment point on the vehicle body side via the elastic member of the suspension arm is set to the same position as that of the conventional suspension arm pivotally mounted, the vertical stroke of the suspension as seen from the side of the vehicle body As a result, the inclination of the normal line at the ground point to the ground with respect to the locus of the ground point becomes large. In order to make the elastic member bent upward, for example, as described in claim 4, the vehicle body side mounting surface is placed on the vehicle rear side with respect to the line connecting the both end mounting points. This is achieved by tilting upward and fixing.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to the drawings. The first embodiment is an example adopted for the front suspension. First, the configuration will be described. As shown in FIG. 1, a suspension member 1 elastically supported on the vehicle body side extends in the vehicle width direction, and both left and right ends of the suspension member 1 can swing vertically. One end of the transverse link 2 is attached to the.

Each transverse link 2 extends outward in the vehicle width direction and its outer end is connected to a wheel support member 3 made of a knuckle or the like. The lower end of the suspension strut 4 is fixed to the upper portion of the wheel support member 3, and the suspension strut 4 extends upward and its upper end is elastically supported on the vehicle body side. The wheel support member 3 and the transverse link 2 form a wheel side member.

The rear ends 5a of the radius rods 5 are rigidly connected to the upper surfaces of the left and right transverse links 2, respectively, and the radius rods 5 extend forward in the front-rear direction of the vehicle body. Although the radius rod on the right wheel side (left side in the figure) is not shown in FIG. 1, it is arranged symmetrically with the left wheel side (right side in the figure). The radius rod 5 is, for example, a CFR
A plate-like elastic body made of a fiber reinforced resin such as P or GFRP, a spring steel plate, a steel member such as FRP, and the like. It is elastically deformable.

The front end of each radius rod 5 is
It is rigidly connected to the tension rod 6, and the tension rod 6 is elastically supported on the vehicle body side 7 as shown in FIG. At this time, the mounting angle of the front end portion 5b of the radius rod 5 to the tension rod 6 is as shown in FIG.
The radius rod 5 is set so as to be tilted upward by a predetermined angle θ _f toward the front of the vehicle with respect to the tilt of the straight line L1 connecting the both-end mounting portions 5a and 5b. Therefore, when the vehicle is in the standard posture, the radius rod 5 is bent below a straight line L1 connecting the both end mounting portions 5a and 5b (which is naturally flat when viewed from above). The default setting is.

Reference numeral 8 in FIG. 1 denotes a stabilizer for connecting the left and right transverse links 2, and 9 in FIG. 2 denotes wheels 9. In the vehicle suspension having the above-described structure, the transverse link 2 swings in the vertical direction around the vehicle body side mounting portion in accordance with the bound and rebound of the wheel 9 to move the wheel 9 in the vehicle width direction. regulate.

Further, as the wheel 9 bounds and rebounds, the radius rod 5 bends up and down around the vehicle body side mounting portion 5b to regulate the movement of the wheel 9 in the vehicle longitudinal direction. At this time, the radius rod 5 made of an elastic body
Is initially set to be bent downwards,
As shown in FIG. 3, the wheel-side mounting portion 5a of the radius rod 5 further bends when bounding and moves upward while being displaced forward and backward in the vehicle body body along with bounding.

On the other hand, at the time of rebound, the initially set deflection changes in a decreasing direction, so that the wheel-side mounting portion 5a of the radius rod 5 moves downward while being displaced rearward in the vehicle front-rear direction. Therefore, as compared with the case where the radius rod is made of a rigid body as in the conventional case, the locus of the wheel-side mounting portion 5a of the radius rod 5 during the suspension stroke moves forward in the vehicle front-rear direction at the time of bouncing. As a result, the ground point locus S1 of the wheel 9 associated with the suspension stroke is also set to move forward in the front-rear direction of the vehicle body when bounding.

In order to realize the locus of the wheel-side mounting portion 5a as described above by the conventional radius rod 5 made of a rigid body, the vehicle-body-side mounting point of the radius rod 5 is lowered to the position indicated by A1 in FIG. Need to be set. Then, when the vehicle is braked, the front part of the vehicle body in the front-rear direction sinks downward, and the front wheels 9 bounce. As described above, the front suspension of this embodiment causes the wheels at the time of bouncing. The ground contact point locus S1 of 9 moves forward in the vehicle front-rear direction as compared to the conventional case, and the pitching moment around the vehicle center of gravity becomes smaller than in the conventional case. Therefore, the anti-dive performance during braking is improved and the change in the vehicle body posture is reduced. As a result, the maneuverability is improved.

That is, it is possible to improve the anti-dive performance during braking without changing the setting point of the vehicle body side mounting portion of the radius rod 5 downward. In the above embodiment, the radius rod 5 made of a plate-like elastic body is initially set so as to be bent downward so as to be bent downward, but the radius rod 5 is bent to be bent downward. A molded elastic member may be used so that it is in a state of being convexly bent downward at the time of initial setting.

Further, in the above embodiment, the radius rod 5
The radius rod 5 can be mounted by inclining the vehicle body side mounting angle above the angle connecting the both end mounting portions 5a and 5b.
Is bent downward, the radius rod 5 may be bent downward by inclining the mounting angle of the wheel-side mounting portion 5a below the inclination connecting the both-end mounting portions 5a and 5b. By setting both the mounting angles of the parts 5a and 5b in the vertical direction as described above,
The radius rod 5 may be initially set in a state of being bent downward.

Next, the second embodiment will be described. The second embodiment is an example adopted in the rear suspension.
First, the structure will be described. As shown in FIG. 4, a suspension member (not shown) extends in the vehicle width direction, and the suspension member is elastically supported on the vehicle body side. The left and right ends of the suspension member are respectively connected to the inner ends of two parallel links 11 which are paired so as to be vertically swingable via rubber bushes.

Each pair of parallel links 11 forming a set includes
Each extends outward in the vehicle width direction, and its outer end portion is connected to a wheel support member 12 constituting a wheel side member so as to be vertically swingable. The wheel support member 12 rotatably supports a wheel (not shown), and the lower end portion of the suspension strut 13 is fixed to the upper portion thereof. The suspension strut 13 extends upward and its upper end is elastically supported on the vehicle body side.

Further, the rear end of the radius rod 15 is rigidly connected to the lower front side of the wheel support member 12 via a bracket 14 as shown in FIG. The radius rod 15 is, for example, a fiber reinforced resin such as CFRP or GFRP,
It is a flat plate-shaped elastic body formed of a spring steel plate, a steel member such as FRP, or the like, and is elastically deformable in the vertical direction when the plate thickness direction is arranged in the vertical direction.

The radius rod 15 fixed to the lower front side of the wheel support member 12 extends forward in the front-rear direction of the vehicle body while curving slightly in the vehicle width direction in order to avoid buffering with other members (not shown). The front end portion 15b is rigidly connected to the side member 16 that constitutes the vehicle body frame. At this time, the mounting angle of the front end portion 15b of the radius rod 15 to the side member 16 is, as shown in FIG. 6, lower than the inclination of the straight line L2 connecting the mounting portions 15a and 15b at both ends of the radius rod 15 toward the front of the vehicle. At a predetermined angle θ
_When the vehicle is in the standard posture, the radius rod 15 is set so as to incline only by _r so that both ends of the radius rod 15 are attached.
It is initially set in a state of being bent above a straight line L2 connecting 5a and 15b.

Reference numeral 18 denotes the left and right parallel links 11.
Is a stabilizer that connects the. In the vehicle suspension having the above-described configuration, the parallel link 11 swings up and down around the vehicle body side mounting portion as the wheels 17 bounce and rebound, and restricts the movement of the wheels 17 in the vehicle width direction. . Further, as the wheel 17 bounds and rebounds, the radius rod 15 bends up and down around the vehicle body side mounting portion 15b to regulate the movement of the wheel 17 in the vehicle body front-rear direction.

At this time, since the radius rod 15 made of an elastic material is initially set in a state of being bent upwardly, as shown in FIG. 7, the radius rod 15 is further bent at the time of rebound, and the radius rod 15 is attached to the wheel side. The part 15a is
As it rebounds, it moves downward while moving forward and backward in the vehicle body. On the other hand, at the time of bouncing, the wheel side mounting portion 15a of the radius rod 15 moves upward while being displaced rearward in the front-rear direction of the vehicle body because the initially set deflection is reduced.

For this reason, the radius rod 1 is different from the conventional one.
Compared with the case where 5 is made of a rigid body, the locus of the wheel-side mounting portion 15a of the radius rod 15 associated with the suspension stroke moves forward in the vehicle front-rear direction during rebound. As a result, the ground contact point locus S2 of the wheel 17 associated with the suspension stroke is also set to move forward in the vehicle front-rear direction during rebound.

In order to realize the locus of the wheel-side mounting portion 5a as described above with the conventional radius rod 15 made of a rigid body, the radius-rod-side mounting point of the radius rod is set to the position indicated by A2 in FIG. There is a need to. When the vehicle is braked, the rear part of the vehicle body in the front-rear direction floats upward and the rear wheels 17 rebound. As described above, in the rear suspension of this embodiment, the wheels 17 at the time of rebound are rebounded. Since the ground contact point locus S1 moves forward in the vehicle front-rear direction as compared with the conventional case, the pitching moment around the vehicle center of gravity becomes smaller than in the conventional case, the anti-lift performance during braking is improved, and the change in the vehicle body posture is reduced. Operability is improved.

That is, the anti-lift performance during braking can be improved without changing the mounting point of the radius rod 15 on the vehicle body side. On the contrary, it is also possible to set the mounting point of the radius rod 15 on the vehicle body side lower than the conventional setting. Therefore, as shown in FIG. 8, it is possible to improve the anti-lift performance while ensuring a desired height of the sitting position B of the rear seat 19.

In the above embodiment, the radius rod 15 made of a flat plate-like elastic member is bent upward so as to be convexly bent upward. However, an elastic member formed in a curved upward convex shape is used. It may be used and may be in a state of being convexly bent upward at a predetermined setting. Further, in the above-described embodiment, the mounting angle of the radius rod 15 on the vehicle body side is set to
The radius rod 15 is bent upward by inclining downwardly from the angle connecting the 15b, but by inclining the mounting angle of the wheel side mounting portion 15a higher than the angle connecting the both end mounting portions 15a and 15b. The radius rod 1
5 may be bent upward, or both end mounting portions 15a, 1
The radius rod 15 may be initially set in a state of being bent upward by setting the mounting angles of the 5b together as described above.

Next, a third embodiment will be described. The second embodiment is an example adopted for the parallel link 11 type rear suspension, whereas the third example is an example adopted for the multi-link type rear suspension. It should be noted that FIG. 9 is a diagram showing a configuration of a corresponding conventional multi-link type rear suspension.

First, the structure will be described. As shown in FIG. 10, the transverse member 21a extends in the vehicle width direction.
Side support members 21b are respectively provided at both left and right ends of the transverse member 21a so as to extend in the front-rear direction of the vehicle body.
The suspension member 21 is elastically supported on the vehicle body side via insulators attached to the side support members 21b.

Two lower links 22 are attached to the lower portions of the left and right ends of the suspension member 21 so as to be vertically swingable via rubber bushes. Each lower link 22 extends outward in the vehicle width direction, and an outer end portion thereof is swingably connected to a lower portion of a wheel support member 23 that constitutes a wheel side member. Further, upper arms 24, which are A arms, are attached to upper portions of both left and right ends of the suspension member 21 so as to be vertically swingable via rubber bushes. Each upper arm 2
Numeral 4 extends outward in the vehicle width direction, and its outer end is swingably connected to the upper portion of the wheel support member 23.

The wheel support member 23 rotatably supports a wheel (not shown), and its movement in the vehicle width direction is restricted by the upper lower link 22 and the upper arm 24. The rear end of the radius rod 25 is rigidly attached to the lower front side of the wheel support member 23. The radius rod 25 extends substantially forward in the front-rear direction of the vehicle body, and its front end is rigidly attached to the front end of the side support member 21b.

In FIG. 10, only the radius rod 25 on the right wheel side (left side in the figure) is shown. The radius rod 25 is a flat plate-shaped elastic body formed of a fiber reinforced resin such as CFRP or GFRP, a steel member such as a spring steel plate, FRP, or the like as a raw material, and is arranged with the plate thickness direction oriented vertically. By doing so, it is elastically deformable in the vertical direction.

At this time, the mounting angle of the front end portion 25b of the radius rod 25 to the front end portion of the side support member 21b is the same as that of the radius rod 25 of the second embodiment as shown in FIG. When the vehicle is in the standard posture, the radius rod 25 connects both ends of the mounting portions 25a and 25b by setting the inclination of the mounting portions 25a and 25b toward the front of the vehicle downward by a predetermined angle. It is initially set to be bent above the straight line.

Reference numeral 26 denotes the left and right parallel links 11
And 27 are suspension struts. In the vehicle suspension configured as described above, the lower link 22 and the upper arm 24 swing in the up-down direction around the vehicle body side mounting portion to move the wheel in the vehicle width direction as the wheel bounces and rebounds. regulate.

Further, as the wheel bounces and rebounds, the radius rod 25 bends up and down around the vehicle body side mounting portion to restrict the movement of the wheel in the vehicle body front-rear direction. At this time, since the radius rod 25 made of an elastic body is initially set in a state of being bent upwardly, similarly to FIG. 7, the radius rod 25 is further bent at the time of rebound, and the wheel side mounting portion 15a of the radius rod 25 is As it rebounds, it moves downward while moving forward and backward in the vehicle body.

On the other hand, at the time of bouncing, since the initially set deflection changes so as to decrease, the radius rod 2
The wheel-side mounting portion 15a of No. 5 moves upward while being displaced rearward in the vehicle front-rear direction. Therefore, as compared with the conventional case where the radius rod 25 is made of a rigid body, the locus of the wheel-side mounting portion 15a of the radius rod 25 during the suspension stroke moves forward in the vehicle front-rear direction during rebound. As a result, the locus of the ground contact point of the wheel associated with the suspension stroke is also set to move forward in the vehicle front-rear direction during rebound.

The wheel-side mounting portion 25a as described above is used.
In order to realize the locus of No. 2 with the conventional radius rod made of a rigid body, it is necessary to change the setting point of the radius rod on the vehicle body side to the upper side and set it. Then, when the vehicle is braked, the rear part of the vehicle body in the front-rear direction floats upward,
Although the wheels on the rear side rebound, as described above, in the rear suspension of this embodiment, the ground contact point locus of the wheels at the time of rebound moves forward in the vehicle front-rear direction compared to the conventional one,
Since the pitching moment around the center of gravity of the vehicle is smaller than in the conventional case, the anti-lift performance during braking is improved, the posture change of the vehicle body is reduced, and the maneuverability is improved.

That is, the anti-lift performance during braking can be improved without changing the vehicle body side mounting point of the radius rod 25 to the upper side. Further, the mounting point of the radius rod 25 on the vehicle body side can be set lower than in the conventional case. In the above embodiment, the radius rod 25 made of a plate-like elastic body is bent upward so as to be convexly bent upward. However, an elastic member formed in a curved upward convex shape is used. It may be in a state of being convexly bent upward at a predetermined setting.

Further, in the above embodiment, the radius rod 2
The mounting angle of the vehicle body side of No. 5 is set to the both end mounting portions 25a and 25b.
The radius rod 25 is bent upward by inclining it downwardly than the angle connecting the two wheels.
The radius rod 25 may be bent upward by inclining the mounting angle of the both ends above the angle connecting the both end mounting parts 25a and 25b.
It is also possible to set both of the mounting angles of the above inclining in the vertical direction as described above so that the radius rod 25 can be initially set so as to be bent upward.

Next, a fourth embodiment will be described. 11. FIG. 11 is a diagram showing the configuration of a corresponding conventional multi-link type rear suspension, which is the wheel support member 3
The lower arm 32 consisting of the A arm connected to the lower part of 1
The lower arm 32 extends diagonally forward of the vehicle body in the front-rear direction and is connected to the front side portion of the side member 33a of the suspension member 33 that extends forward (front side) of the vehicle body 32a. It also has a role.

First, the structure will be described. As shown in FIG. 12, a wheel (not shown) is rotatably supported by a wheel supporting member 41 which constitutes a wheel side member, and a front upper link 42 is provided above the wheel supporting member 41. Also, the outer end portion of the rear upper link 43 is connected so as to be swingable in the vertical direction.
The front upper link 42 and the rear upper link 43
Respectively extend inward in the vehicle width direction, and their inner ends are connected to the suspension members 44 so as to be vertically swingable.

Further, an outer end portion of a lower arm 45 constituting a wheel side member is connected to a lower portion of the wheel support member 41 so as to be vertically swingable. The lower arm 45 extends inward in the vehicle width direction, and an inner end portion of the lower arm 45 is swingably connected to a lower portion of a suspension member 44 that constitutes a vehicle body side member. The suspension member 44 extends in the vehicle width direction, and side members 44a extend forward in the vehicle body front-rear direction from both left and right ends on the vehicle body front-rear direction front side.

The rear end portion 46a of the radius rod 46 is rigidly attached to the upper surface of the lower arm 45. The radius rod 46 extends substantially forward in the front-rear direction of the vehicle body, and its front end portion 46b is rigidly attached to the front end portion side of the side member 44a via an auxiliary bracket 47. The radius rod 46 is, for example, CFRP or GF.
A flat plate-like elastic body made of a material such as a fiber reinforced resin such as RP, a spring steel plate, a steel member such as FRP, which is elastic in the vertical direction when the plate thickness direction is arranged in the vertical direction. It is transformable.

At this time, the mounting angle of the front end portion 46a of the radius rod 46 to the side member 44a is the same as the mounting of the radius rod 46 of the second embodiment as shown in FIG.
When the vehicle is in the standard posture, the radius rod 46 is set above the straight line connecting both ends of the radius rod 46 by setting the vehicle so that it tilts downward by a predetermined angle toward the front of the vehicle from the inclination connecting the a and 46b. It is initially set in a bent state.

Reference numeral 47 is a stabilizer and 48 is a suspension strut. In the vehicle suspension configured as described above, the lower arm 45 and the upper links 42, 4 are associated with the bouncing and rebounding of the wheels.
3 swings up and down about the vehicle body side mounting portion to regulate movement of the wheels in the vehicle width direction. Further, as the wheel bounces and rebounds, the radius rod 46 bends up and down around the vehicle body side mounting portion to restrict the movement of the wheel in the vehicle body front-rear direction.

At this time, since the radius rod 46 made of an elastic body is initially set in a state of being bent upwardly, it is further bent at the time of rebound, so that the wheel side mounting portion 46a of the radius rod 46 is rebounded. Along with this, it moves downward while being displaced forward and backward in the vehicle body. On the other hand, at the time of bouncing, since the initially set deflection changes so as to decrease, the wheel-side mounting portion 15a of the radius rod 46 moves upward while being displaced rearward in the vehicle front-rear direction.

For this reason, as in the conventional case, the radius rod 4
Compared to the case where 6 is made of a rigid body, the locus of the wheel-side mounting portion 46a of the radius rod 46 that accompanies the suspension stroke moves forward in the vehicle front-rear direction during rebound. As a result, the locus of the ground contact point of the wheel associated with the suspension stroke is also set to move forward in the vehicle front-rear direction during rebound.

The wheel-side mounting portion 46a as described above is used.
In order to realize the locus of No. 1 with the conventional radius rod made of a rigid body, it is necessary to change the setting point of the radius rod on the vehicle body side to the upper side and set it. Then, when the vehicle is braked, the rear part of the vehicle body in the front-rear direction floats upward and the rear wheels rebound, but as described above,
In the rear suspension of this embodiment, the locus of the ground contact point of the wheel at the time of rebound moves forward in the vehicle body front-rear direction compared to the conventional case, and the pitching moment around the vehicle center of gravity becomes smaller than in the conventional case. Is improved, the posture change of the vehicle body is reduced, and the maneuverability is improved.

That is, the anti-lift performance during braking can be improved without changing the vehicle body side attachment point of the radius rod 46 to the upper side. On the contrary, it is possible to set the mounting point of the radius rod 46 on the vehicle body side lower than the conventional setting. In the above embodiment, the radius rod 46 made of a plate-like elastic body is bent upward so as to be convexly bent upward. However, an elastic body formed in a curved upward convex shape is used. It may be in a state of being convexly bent upward at a predetermined setting.

Further, in the above embodiment, the radius rod 4
The vehicle body side mounting angle of 6 is set to both end mounting portions 46a, 46b.
The radius rod 46 is bent upward by inclining the radius rod 46 downward from the angle at which the wheels are attached.
The radius rod 46 may be bent upward by inclining the mounting angle of the above to an angle more than the angle connecting the both end mounting portions 46a and 46b, or both end mounting portions 46a and 46b.
It is also possible to set both of the mounting angles of the above inclining in the vertical direction as described above to initially set the state in which the radius rod 46 is bent upward.

Next, the fifth embodiment will be described. Fifth
The embodiment is an example applied to a semi-trailing type rear suspension. First, the configuration will be described. As shown in FIGS. 13 and 14, a wheel (not shown) is rotatably supported by a wheel support member 51 that constitutes a wheel-side member, and a trailing arm type is supported with respect to the wheel support member 51. Semi-trailing arm 52 that constitutes the suspension arm of
The rear ends are connected.

The semi-trailing arm 52 extends forward in the front-rear direction of the vehicle body. An elastic member 53 is rigidly attached to the front end of the semi-trailing arm 452,
The elastic member 53 extends forward in the front-rear direction of the vehicle body. The elastic member 53 is a flat plate-shaped elastic body formed by using, for example, a fiber reinforced resin such as CFRP or GFRP, a steel member such as a spring steel plate, FRP, or the like. By being installed, it is elastically deformable in the vertical direction.

The front end portion 53a of the elastic member 53 is rigidly attached to the upper surface of the suspension member 54 which extends in the vehicle width direction and constitutes a vehicle body side member. At this time, the mounting angle of the front end portion 53b of the elastic member 53 to the suspension member 54 is, as shown in FIG. 14, the vehicle front side with respect to the inclination of the line L3 connecting both end mounting portions 53a and 53b of the elastic member 53. When the vehicle is in the standard posture, the elastic member 53 is set so as to incline downward at a predetermined angle θ _r.
It is initially set in a state of being bent above a straight line L3 connecting a and 53b.

Reference numeral 55 is a stabilizer, 56 is a suspension strut, 57 is a differential gear, and 58 is a barrel-shaped coil spring. In the vehicle suspension configured as described above, the semi-trailing arm 52 restricts the movement of the wheel support member 51 and the wheels that move up and down as the wheels bounce and rebound in the vehicle width direction and the vehicle body front-rear direction.

At this time, the elastic member 53 made of an elastic body.
Is initially set to be bent upwards, so
During the rebound, the arm-side mounting portion 53a of the elastic member 53 is further bent and moves downward while being displaced forward in the front-rear direction of the vehicle body along with the rebound. On the other hand, at the time of bouncing, the initially set deflection changes so as to decrease, so that the arm-side mounting portion 53a of the elastic member 53 moves upward while being displaced rearward in the vehicle front-rear direction.

Therefore, as compared with the case where the vehicle body side portion of the semi-trailing arm 52 is pivotally mounted as in the conventional case, the locus of the arm side attachment portion 53a of the elastic member 53 accompanying the suspension stroke is the vehicle longitudinal direction at the time of rebound. Move forward. As a result, the wheel-side mounting portion of the semi-trailing arm 52 and the ground contact point locus of the wheel associated with the suspension stroke are also set to move forward in the vehicle front-rear direction during rebound.

In order to realize the locus of the wheel-side mounting portion of the semi-trailing arm as described above by the conventional semi-trailing arm having the body-side portion axially attached, It is necessary to change the side mounting point upward and set. When the vehicle is braked, the rear part of the vehicle body in the front-rear direction floats upward and the rear wheels rebound.As described above, in the rear suspension of this embodiment, the ground contact point of the wheels at the time of rebound. The trajectory moves forward and backward from the vehicle body compared to the past, and the pitching moment around the center of gravity of the vehicle becomes smaller than before, so the anti-lift performance during braking is improved and the posture change of the vehicle body is reduced to improve maneuverability. Will get better.

That is, it is possible to improve the anti-lift performance during braking without changing the mounting point of the semi-trailing arm 52 on the vehicle body side to the upper side. Furthermore, the vehicle body side attachment point of the semi-trailing arm 52 can be set lower than the conventional vehicle body side attachment point.
Further, in the above-described embodiment, the elastic member 53 made of a flat plate-like elastic member is bent upward so as to be bent upwardly, but the elastic member 53 is formed in a state bent upwardly.
It is also possible to use the and to make a state of being convexly bent upward at a predetermined setting.

In the above embodiment, the elastic member 53 is bent upward by inclining the mounting angle of the elastic member 53 on the vehicle body side from the angle connecting the both end mounting portions 53a and 53b. The elastic member 53 may be bent upward by inclining the mounting angle of the arm-side mounting portion 53a above the angle connecting the both-end mounting portions 53a and 53b, or the mounting angle of the both-end mounting portions 53a and 53b. By setting both of them inclining as described above, the elastic member 53 may be initially set in a state of being bent upward.

In the above embodiment, the semi-trailing arm type rear suspension is used, but a full trailing type rear suspension may be used. Further, the configurations of the vehicle suspensions of all the above-mentioned embodiments are examples, and a vehicle suspension or a trailing arm type suspension arm provided with a radius rod that extends in the vehicle front-rear direction and connects the wheel side member and the vehicle body side member. Any suspension provided can be applied to a vehicle suspension having another configuration.

[0088]

As described above, in the vehicle suspension according to the first aspect of the present invention, the radius rod has the front end thereof rigidly attached to the vehicle body side member and is elastically deformed in the vehicle body vertical direction. The height of the mounting point of the radius rod on the vehicle body side can be changed by initially constructing the elastic rod to be bent downward from the straight line connecting the both end mounting portions in the standard posture of the vehicle. None, or even if the height of the vehicle body side attachment point of the radius rod is set higher than in the past, the nose dive during vehicle braking can be reduced.

That is, it is possible to improve the anti-pitching performance of the front suspension while ensuring the minimum ground clearance in the vehicle layout. In a vehicle suspension according to a second aspect of the present invention, the radius rod is formed of an elastic body whose front end is rigidly attached to the vehicle body side member and is elastically deformable in the vehicle body vertical direction, and has a vehicle standard posture. At some times, the initial setting was made so that it bends above the straight line connecting the both end mounting parts, without changing the height of the mounting point on the vehicle body side of the radius rod, or on the vehicle body side mounting of the radius rod more than before. Even if the point height is set low, the tail lift during vehicle braking can be reduced.

That is, the anti-pitching performance of the rear suspension can be improved while ensuring the height of the seating position of the rear seat in the vehicle layout. A vehicle suspension according to a third aspect of the present invention is a rear suspension including a trailing arm type suspension arm that extends in a vehicle body front-rear direction and connects a wheel side member and a vehicle body side member to each other. And the vehicle body side member are connected via an elastic member made of an elastic body that extends in the vehicle body front-rear direction and is elastically deformable in the vehicle body vertical direction, and both end members of the elastic member are rigidly connected to the suspension arm and the vehicle body side member, respectively. In addition, since the initial setting is made such that the suspension arm is bent above a straight line connecting both end mounting portions, the height of the vehicle body side mounting point of the suspension arm is not changed, or the suspension arm Even if the height of the mounting point on the vehicle body side is set low, the tail lift during braking of the vehicle can be reduced.

That is, it is possible to improve the anti-pitching performance of the rear suspension while ensuring the height of the seating position of the rear seat in the vehicle layout. In order to make the radius rod and the elastic member made of the elastic body bent up and down, for example, as described in claim 4, the vehicle body side mounting portion of the radius rod or the elastic member made of the elastic body is attached to both ends thereof. It may be realized by mounting the member on the vehicle body side while inclining it by a predetermined angle in the vertical direction with respect to the straight line connecting the mounting portions.

That is, the radius rod or elastic member made of the elastic body can be initially set in a vertically bent state by a simple means of changing the mounting angle on the vehicle body side.

[Brief description of drawings]

FIG. 1 is a perspective view showing a vehicle suspension of a first embodiment according to the invention.

FIG. 2 is a side view showing a state of a radius rod of the vehicle suspension of the first embodiment according to the present invention.

FIG. 3 is a diagram showing the behavior of the radius rod of the vehicle suspension of the first embodiment according to the present invention during suspension strut.

FIG. 4 is a perspective view showing a vehicle suspension according to a second embodiment of the present invention.

FIG. 5 is a view showing a bracket for attaching a wheel side attachment portion of a radius rod of a vehicle suspension according to a second embodiment of the present invention.

FIG. 6 is a side view showing a state of a radius rod of a vehicle suspension according to a second embodiment of the present invention.

FIG. 7 is a diagram showing a behavior of a radius rod of a vehicle suspension according to a second embodiment of the present invention during suspension strut.

FIG. 8 is a diagram showing a positional relationship between a radius rod and a rear seat of a vehicle suspension according to a second embodiment of the present invention.

FIG. 9 is a perspective view showing an example of a conventional vehicle suspension corresponding to a third embodiment of the invention.

FIG. 10 is a perspective view showing a part of the vehicle suspension of the third embodiment according to the present invention in a perspective manner.

FIG. 11 is a perspective view showing an example of a conventional vehicle suspension corresponding to the fourth embodiment of the invention.

FIG. 12 is a perspective view showing a vehicle suspension according to a fourth embodiment of the present invention.

FIG. 13 is a perspective view showing a vehicle suspension according to a fifth embodiment of the present invention.

FIG. 14 is a side view showing a vehicle suspension according to a fifth embodiment of the present invention.

FIG. 15 is a diagram showing an example of a conventional vehicle suspension.

FIG. 16 is a diagram for explaining a pitching moment that acts on the front side during braking.

FIG. 17 is a diagram showing the behavior of the radius rod in the front suspension with respect to the suspension stroke.

FIG. 18 is a diagram showing a ground contact point locus according to a height of a vehicle body side attachment point of a radius rod in a front suspension.

FIG. 19 is a diagram for explaining a pitching moment that acts on the rear side during braking.

FIG. 20 is a diagram showing a behavior of a radius rod in a rear suspension with respect to a suspension stroke.

FIG. 21 is a diagram showing a ground contact point locus according to a height of a vehicle body side attachment point of a radius rod in a rear suspension.

FIG. 22 is a diagram showing a positional relationship between a height position of a vehicle body side attachment point of a radius rod in a rear suspension and a seating position of a rear seat.

[Explanation of symbols]

 1 Suspension Member 2 Transverse Link (Wheel Side Member) 3 Wheel Support Member (Wheel Side Member) 5 Radius Rod 5a Wheel Side Attachment 5b Vehicle Body Side Attachment 6 Tension Bracket (Vehicle Side Member) 11 Parallel Link 12 Wheel Support Member (Wheel) Side member) 15 Radius rod 16 Side member (vehicle body side member) 21 Suspension member (vehicle body side member) 23 Wheel support member (wheel side member) 25 Radius rod 41 Wheel support member (wheel side member) 44 Suspension member (vehicle body side member) 45 Lower link (wheel side member) 46 Radius rod 51 Wheel support member (wheel side member) 52 Semi-trailing arm 53 Elastic member 54 Suspension member (vehicle body side member) S1, S2 Ground point locus

Claims (4)

[Claims] 1. A front suspension including a radius rod that extends in the vehicle body front-rear direction and has one end connected to a wheel side member and the other end connected to a vehicle body side member, wherein the radius rod has a front end portion on the vehicle body side. It is composed of an elastic body that is rigidly attached to a member and is elastically deformable in the vertical direction of the vehicle body, and it is initially set in a state in which it is bent below the straight line connecting both end attachment parts when the vehicle is in the standard posture Characteristic vehicle suspension. 2. A rear suspension including a radius rod that extends in the vehicle body front-rear direction and connects one end to a wheel side member and the other end to a vehicle body side member, wherein the radius rod has a front end portion on the vehicle body side. It is composed of an elastic body that is rigidly attached to a member and is elastically deformable in the vertical direction of the vehicle body, and is initially set in a state in which it is bent above a straight line connecting both end attachment parts when the vehicle is in the standard posture. Characteristic vehicle suspension. 3. A rear suspension including a trailing arm type suspension arm extending in the vehicle body front-rear direction and having one end portion connected to a wheel side member and the other end portion connected to a vehicle body side member. The vehicle body side member is connected to the vehicle body side member via elastic members made of an elastic body that extends in the vehicle body front-rear direction and is elastically deformable in the vehicle body vertical direction, and both end members of the elastic member are rigidly coupled to the suspension arm and the vehicle body side member, respectively. A vehicle suspension characterized in that the vehicle is initially set in a state of being bent upward with respect to a straight line connecting both end mounting portions. 4. The radius rod or elastic member formed of the elastic body is attached to the vehicle body side member by inclining the vehicle body side attachment portion by a predetermined angle in the vertical direction with respect to a straight line connecting both end attachment portions thereof, whereby the elastic body is removed from the elastic body. The vehicle suspension according to any one of claims 1 to 3, wherein the radius rod or the elastic member is bent upward or downward.