JPH06278429A - Multilink-type suspension device - Google Patents

Abstract

PURPOSE:To improve the steering stability by generating toe-in in braking. CONSTITUTION:A knuckle N for supporting an axle A of a rear wheel W is connected to a car body B through an upper arm UP and a leading arm LE on the upper part of the axle A and also connected to the car body B through a lower arm LO and a trailing arm TR on the lower part of the axle A and moreover connected to the car body B through a control arm CO on the rear part of the axle A. The load acting on the knuckle N with the braking offsets the outer ends of the upper arm UP and the lower arm LO to the car body inner side, but the outer end of the control arm CO largely separated backward from the outer end of the leading arm LE and the outer end of the trailing arm TR is not offset in the car body lateral direction, so that the rear wheel W is oscillated in the toe-in direction centered on the outer end of the control arm CO.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a knuckle that rotatably supports an axle, five arms that connect the knuckle to a vehicle body so that the knuckle can move up and down, and a damper that damps the vertical movement of the knuckle. Link type suspension device.

[0002]

2. Description of the Related Art Such a multi-link type suspension device is already known as disclosed in Japanese Patent Laid-Open No. 57-134309.

As shown in FIG. 7, the above multi-link suspension system includes an upper arm UP and an upper reading arm ULE that connect a vehicle body B and a knuckle N above an axle A, and a vehicle body B below the axle A. Lower arm LO and lower leading arm LL connecting with knuckle N
E, and a control arm CO that connects the vehicle body B and the knuckle N in front of the axle A.

[0004]

Generally, in a suspension system, it is desirable that the toe-in tendency during braking, that is, the front end of the wheel is biased toward the inside of the vehicle body in order to improve the steering stability, which will be described later. As described above, the conventional multi-link suspension system has a problem in that an appropriate toe-in cannot be generated by the braking force.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a multi-link suspension system capable of generating toe-in by a braking force and improving steering stability. .

[0006]

In order to achieve the above object, the invention described in claim 1 includes a knuckle for rotatably supporting an axle and five knuckles for vertically movably connecting the knuckle to a vehicle body. In a multi-link suspension system including an arm and a damper that damps the vertical movement of a knuckle, the five arms include upper arms that extend in the lateral direction of the vehicle body and connect the vehicle body and the knuckle above an axle. A leading arm that extends from the inside of the vehicle body rearward to the outside of the vehicle body and connects the vehicle body and the knuckle above the axle, a lower arm that extends in the lateral direction of the vehicle body and connects the vehicle body and the knuckle below the axle, and a vehicle body from the inside front of the vehicle body A trailing arm that extends rearward and outward to connect the vehicle body and the knuckle below the axle, and a trailing arm that extends laterally to the vehicle body and connects the vehicle body and the knuckle behind the axle. It consists of a trawl arm, and sets the front-back distance of the control arm outer end to the leading arm outer end to be larger than the front-back distance of the upper arm outer end to the leading arm outer end. The front-rear distance of the outer end of the control arm with respect to the outer end of the trailing arm is set to be larger than the front-rear distance of the.

According to the second aspect of the present invention, a knuckle that rotatably supports the axle, five arms that connect the knuckle to the vehicle body so that the knuckle can move up and down, and a damper that damps the vertical movement of the knuckle. In the multi-link suspension system provided with the above-mentioned five arms, the upper arms extend in the left-right direction of the vehicle body and connect the vehicle body and the knuckle above the axle, and extend from the inside of the vehicle body front toward the outside of the vehicle body above the axle. With a trailing arm that connects the car body and knuckle with
A lower arm that extends in the lateral direction of the vehicle body and connects the vehicle body and the knuckle below the axle, a leading arm that extends from the inside of the vehicle body rearward to the outside of the vehicle body front and connects the vehicle body and the knuckle below the axle, and extends in the vehicle body lateral direction. It consists of a control arm that connects the vehicle body and the knuckle in front of the rear axle, and the front-back distance of the outer end of the control arm to the outer end of the trailing arm is longer than the front-back distance of the outer end of the upper arm to the outer end of the trailing arm. In addition to being set large, the front-rear distance of the control arm outer end to the leading arm outer end is set to be larger than the front-rear direction distance of the lower arm outer end to the leading arm outer end.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 show a first embodiment of the present invention. FIG. 1 is a plan view of a suspension system, FIG. 2 is a two-direction arrow view (rear view) of FIG. 1, and FIG. 3 is a view (side view) taken along line 3-3 of FIG. 1, FIG. 4 is a perspective view of the suspension device, and FIG.

1 to 4 show a suspension system for a right rear wheel W of a front-wheel drive vehicle. An axle A of a rear wheel W including a tire 1, a wheel 2 and a brake disc 3 is rotatably supported by a knuckle N. The upper arm mounting portion 4 protruding upward from the knuckle N and the vehicle body B have ball joints 5 at the outer end and the inner end of the upper arm UP, respectively.
And the vehicle body B, which are connected to each other via the rubber bush joint 6 and project upward from the knuckle N, and the outer end and the inner end of the leading arm LE are respectively provided with the rubber bush joints 8 and 9. Are connected. The upper arm UP and the leading arm LE are arranged so as to be located in substantially the same horizontal plane above the axle A.
Extends in the left-right direction of the vehicle body, and the leading arm LE extends from the inner rear side of the vehicle body to the outer front side of the vehicle body.

Outer end and inner end of the lower arm LO are connected to the lower arm mounting portion 10 projecting downward from the knuckle N and the vehicle body B through rubber bush joints 11 and 12, respectively, and project downward from the knuckle N. The trailing arm attachment portion 13 and the vehicle body B are connected at their outer ends and inner ends via rubber bush joints 14 and 15, respectively. The lower arm LO and the trailing arm TR are arranged so as to be located substantially in the same horizontal plane below the axle A,
The lower arm LO extends in the left-right direction of the vehicle body, and the trailing arm TR extends from the front inside of the vehicle to the outside rear of the vehicle.

As described above, by disposing the upper arm UP and the lower arm LO in the left-right direction of the vehicle body, the load in the left-right direction of the vehicle body input from the road surface to the knuckle N is effectively received and the rear wheel W is Caster rigidity and camber rigidity can be increased.

As is apparent from FIG. 3, the front end of the leading arm LE is slightly higher than the rear end in a side view, and the front end of the trailing arm TR is also slightly higher than the rear end. Therefore, when the rear wheel W strokes upward due to unevenness of the road surface or the like, the rubber bush joint 8 at the outer end (front end) of the leading arm LE swings rearward and upward as shown by the arrow a, and the trailing arm The rubber bush joint 14 at the outer end (rear end) of TR swings rearward and upward of the vehicle body as indicated by an arrow b. As a result, the knuckle N moves slightly rearward of the vehicle body together with the rear wheel W, and thus the impact input to the rear wheel W due to the unevenness of the road surface can be buffered.

On the control arm attachment portion 16 protruding from the knuckle N to the rear of the vehicle body and the vehicle body B, the outer end and the inner end of the control arm CO are respectively ball joints 1.
7 and a rubber bush joint 18 are connected. The control arm CO extends in the left-right direction of the vehicle body in substantially the same horizontal plane as the lower arm LO and the trailing arm TR.

A damper mounting portion 19 protruding from the knuckle N to the inside of the vehicle body has a damper D whose upper end is supported by the vehicle body B.
The lower ends of are connected. By using the space formed between the upper arm UP and the leading arm LE to arrange the damper D on the axle of the axle A, the pitching moment due to the load from the road surface is prevented and the damper D is smooth. Not only is it possible to make a stroke, but it is not necessary to support the suspension arm to counter the pitching moment, so the spring rate of the bush of the suspension arm can be lowered and the riding comfort can be improved.

When the braking force is applied to the rear wheel W, the rear wheel W moves on the intersection K ₁ on the extension line of the upper arm UP and the leading arm LE and the extension line of the lower arm LO and the trailing arm TR, as shown in FIG. The toe-in is performed around the virtual kingpin axis K connecting the intersection point K _{2 of} The toe-in action associated with this braking will be described later in detail.

Further, when the vehicle is stopped, the tire 1 contacts the road surface at a point P ₀ just below the axle A, but the contact point P ₁ of the tire 1 during traveling moves rearward of the vehicle body as the traveling speed increases. To do. Ground contact point P ₁ of tire 1 during running
Is located in front of the virtual kingpin axis K, whereby the rear wheel W can be steered toward the inside of the turn during turning to improve the turning performance. That is, for example, when the vehicle is turning to the left, the centripetal force F (see FIG. 4) directed to the left of the vehicle body, which opposes the centrifugal force to the right of the vehicle body, acts on the ground contact point P ₁ of the tire 1 during traveling. Since the centripetal force F acts in front of the virtual kingpin axis K, the rear wheels W are steered to the left, that is, toward the inside of the turn. Steering accompanying the above-described turning occurs similarly for both the left and right rear wheels W.

Further, by adopting the virtual kingpin axis K, a sufficient space can be formed inside the wheel 2, and a storage space for the brake disc 3 and a brake caliper (not shown) can be easily secured.

Since the suspension device for the rear wheel W on the left side of the vehicle body is substantially the same as the suspension device on the right side of the vehicle body described above, a duplicate description thereof will be omitted.

Next, the operation of the first embodiment of the present invention having the above construction will be described.

When a braking force acts on the rear wheel W while the vehicle is traveling, a brake caliper (not shown) provided on the knuckle N restrains the brake disc 3 of the rear wheel W, so that the knuckle N
The torque T (see FIG. 3) acts on the rear wheel W in the rotating direction. As a result, the upper position of the axle A supported by the knuckle N, that is, the upper arm UP and the leading arm L.
A load U to the front of the vehicle body acts on the outer end of E, and the lower end of the axle A, that is, the lower arm LO and the trailing arm T is applied.
A load L to the rear of the vehicle body acts on the outer end of R.

As shown in FIG. 5 (A), when a load U directed toward the front of the vehicle body acts on the outer ends of the upper arm UP and the leading arm LE, the leading arm LE is inclined and the outer ends of the upper arm UP. There because it is disposed in the vicinity of the outer end of the leading arm LE, the load U is decomposed into a component force U ₂ component force U ₁ and leading arm LE direction of upper arm UP direction, the force component U ₁
It compresses the upper arm UP in the direction of arrow a, the component force U ₂
Extends the leading arm LE in the direction of arrow b. As a result, the outer end of the upper arm UP moves to the inner side of the vehicle body, the outer end of the leading arm LE swings forward of the vehicle body, and is retracted to the inner side of the vehicle body, and the upper portion of the axle A of the knuckle N is biased to the inner side of the vehicle body. On the other hand, the control arm CO, which is largely separated rearward from the outer end of the leading arm LE, receives almost no load in the left-right direction of the vehicle body, so that the outer end thereof does not deviate in the left-right direction of the vehicle body. Therefore, the upper part of the axle A of the knuckle N swings in the direction of arrow c around the outer end (ball joint 17) of the control arm CO, and steers the rear wheel W in the toe-in direction.

Further, as shown in FIG. 5 (B), when a load L directed rearward of the vehicle body acts on the outer ends of the lower arm LO and the trailing arm TR, the trailing arm TR is inclined and the lower arm LO has a lower arm LO. Since the outer end is arranged in the vicinity of the outer end of the trailing arm TR, the load L is decomposed into a component force L _{1 in the} lower arm LO direction and a component force L _{2 in the} trailing arm TR direction, and the component force is L ₁ compresses the lower arm LO in the direction of arrow d, and the component force L ₂ extends the trailing arm TR in the direction of arrow e. As a result, the outer end of the lower arm LO moves to the inner side of the vehicle body, the outer end of the trailing arm TR swings rearward of the vehicle body, and is retracted to the inner side of the vehicle body, so that the lower portion of the axle A of the knuckle N is biased to the inner side of the vehicle body. Therefore, the lower part of the axle A of the knuckle N is
The trailing arm TR swings in the direction of the arrow f around the outer end (ball joint 17) of the control arm CO, which is largely offset rearward from the outer end of the trailing arm TR, so that the rear wheel W does not deviate in the lateral direction of the vehicle body. Steer to the toe-in direction.

At this time, the component force U _{1 of the} load U increases as the angle α (see FIG. 5 (A)) formed by the leading arm LE with respect to the longitudinal direction of the vehicle body increases, so that the axle A of the knuckle N is increased.
The upper part can be biased toward the inside of the car body to strengthen the toe-in tendency. Similarly, since the component force L _{1 of the} load L increases as the angle β (see FIG. 5B) formed by the trailing arm TR with respect to the front-rear direction of the vehicle body increases, the lower portion of the axle A of the knuckle N is largely biased toward the inside of the vehicle body. You can increase the tendency of toe-in.

Thus, both the upper part of the axle A and the lower part of the axle A of the knuckle N are swung in the toe-in direction, and the rear wheels W are toe-in with braking and the steering stability is improved. it can.

On the other hand, in the conventional suspension system shown in FIG. 7, as shown in FIG. 8A, the upper part of the axle A of the knuckle N, that is, the upper arm UP and the upper reading arm UL.
The outer end position of E swings in the direction of arrow c ′ around the outer end of the control arm CO, and a toe-in tendency occurs. Further, as shown in FIG. 8B, the axle A of the knuckle N is
The lower part, that is, the outer end positions of the lower arm LO and the lower riding arm LLE swing in the direction of the arrow f ′ around the outer end of the control arm CO, and a toe-out tendency occurs. Therefore, the upper part of the axle A and the axle A of the knuckle N
The force in the opposite direction acts on the lower portion, and the rear wheel W cannot be accurately toeed in with braking.

FIG. 6 shows a second embodiment of the present invention.

In this embodiment, as shown in FIG.
The upper arm U is attached to the upper part of the axle A of the knuckle N and the body B.
P and the trailing arm TR are connected to each other, the rear upper arm UP extends in the left-right direction of the vehicle body, the front trailing arm extends from the front inner side of the vehicle to the rear outer side of the vehicle, and the axle A of the knuckle N is connected. The control arm CO connects the front part and the vehicle body. Further, as shown in FIG. 6 (B), the lower portion of the axle A of the knuckle N and the vehicle body B are connected by a lower arm LO and a leading arm LE, and the front lower arm LO extends in the vehicle body left-right direction.
The trailing arm on the rear side extends from the rear inside of the vehicle to the outer front of the vehicle.

The control arm CO for the outer end of the trailing arm TR is longer than the front-back distance l _{U of the} outer end of the upper arm UP for the outer end of the trailing arm TR.
The front-rear direction distance l _U ′ is set to a large value, and the lower arm LO with respect to the outer end of the leading arm LE is set.
The leading arm L is more than the front-rear direction distance _L L.
The front-rear direction distance l _L ′ of the outer end of the control arm CO with respect to the outer end of E is set to be large.

Thus, as shown in FIG. 6 (A), the rear wheel W
When a load U directed toward the vehicle body acts on the outer ends of the upper arm UP and the trailing arm TR by braking, the component force U _{1 of the} load U extends the upper arm UP in the arrow g direction and the component force U ₂ becomes The trailing arm TR is compressed in the direction of arrow h. As a result, the outer end of the upper arm UP moves to the outer side of the vehicle body, and the outer end of the trailing arm TR swings forward of the vehicle body and is pulled out to the outer side of the vehicle body, and the upper portion of the axle A of the knuckle N is biased to the outer side of the vehicle body. .
At this time, since the load in the lateral direction of the vehicle body hardly acts on the control arm CO that is far away from the outer end of the trailing arm TR, the outer end thereof does not deviate in the lateral direction of the vehicle body. As a result, the upper portion of the axle A of the knuckle N swings in the arrow i direction around the outer end of the control arm CO, and steers the rear wheel W in the toe-in direction.

On the other hand, as shown in FIG. 6B, when the rearward load L acts on the outer ends of the lower arm LO and the leading arm LE during braking of the rear wheel W, the component force L _{1 of the} load L becomes the lower arm LO. decompresses the arrow j direction, a component force L ₂
Compresses the leading arm LE in the direction of arrow k. As a result, the outer end of the lower arm LO moves to the outer side of the vehicle body, and the outer end of the leading arm LE swings rearward of the vehicle body and is pulled out to the outer side of the vehicle body.
The lower part is biased to the outside of the vehicle. As a result, the lower part of the axle A of the knuckle N swings in the direction of the arrow l around the outer end of the control arm CO, which does not deviate in the left-right direction of the vehicle body because it is largely separated forward from the outer end of the leading arm LE. Move and steer the rear wheels W in the toe-in direction.

Thus, both the upper part of the axle A and the lower part of the axle A of the knuckle N are swung in the toe-in direction, and the toe-in of the rear wheel W due to braking is achieved.

Although the embodiment of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and various design changes can be made.

For example, the vehicle body B to which the inner ends of the suspension arms are connected may be either a main frame or a sub frame.

[0035]

As described above, according to the invention described in claim 1, the load acting on the knuckle accompanying braking causes the outer ends of the upper arm and the leading arm to be connected to the upper part of the axle of the knuckle. , The lower end of the knuckle to which the outer ends of the lower arm and the trailing arm are connected together is biased toward the inside of the vehicle body, thereby generating a toe-in around the outer end of the control arm connected to the rear of the knuckle axle, The steering stability during braking can be improved.

According to the second aspect of the present invention, the upper portion of the knuckle to which the outer ends of the upper arm and the trailing arm are connected by the load acting on the knuckle due to braking, the lower arm and the leading arm. The outer end of the arm and the lower part of the axle of the knuckle are both biased toward the outside of the vehicle body, which causes toe-in around the outer end of the control arm connected to the front of the axle of the knuckle and stabilizes the steering during braking. It is possible to improve the sex.

[Brief description of drawings]

FIG. 1 is a plan view of a suspension device according to a first embodiment.

FIG. 2 is a two-direction arrow view (rear view) of FIG.

FIG. 3 is a view (side view) taken along the line 3-3 of FIG.

FIG. 4 is a perspective view of the suspension device.

FIG. 5 is an explanatory diagram of operation

FIG. 6 is an explanatory view of the operation corresponding to FIG. 5 according to the second embodiment.

FIG. 7 is a plan view of a conventional suspension device.

FIG. 8 is an explanatory view of an operation corresponding to FIG. 5 according to a conventional example.

[Explanation of symbols]

A Axle B Body CO Control arm D Damper LE Leading arm LO Lower arm N Knuckle TR Trailing arm UP Upper arm l _U Front-rear distance l _L Front-rear distance l _U ′ Front-rear distance l _L ′ Front-rear distance

Claims (2)

[Claims] 1. A knuck for rotatably supporting an axle (A).
(N) and knuckle (N) can be moved vertically (B)
5 arms connected to (UP, LE, LO, TR, C
O) and a damper that buffers the vertical movement of the knuckle (N)
(D) in a multi-link suspension system, wherein the five arms (UP, LE, LO, TR, CO)
Is extended in the left-right direction of the vehicle body and is above the axle (A).
Upper arm connecting (B) and knuckle (N)
(UP) and extends from the rear inside of the vehicle to the front outside of the vehicle
Connect the body (B) and knuckle (N) above the axis (A)
And the leading arm (LE)
And below the axle (A), with the body (B) and knuckle (N)
The lower arm (LO) that connects the
It extends to the outside of the body and extends below the axle (A) to the vehicle body (B).
Trailing arm (TR) that connects with the kuckle (N)
And extending in the left-right direction of the vehicle body and behind the axle (A)
Control arm that connects (B) and knuckle (N)
(LE) outside the reading arm (LE)
Front-to-back distance of upper arm (UP) outer edge to edge
(L_U) To the outer end of the leading arm (LE)
The front-back distance of the outer end of the control arm (CO)
(L _U′) Is set large and the trailing
In front of the outer end of the lower arm (LO) with respect to the outer end of the dome (TR)
Backward distance (l_L) Than the trailing arm (T
R) In front of control arm (CO) outer end with respect to outer end
Backward distance (l_L′) Is set large
Multi-link suspension system. 2. A knuck for rotatably supporting an axle (A).
(N) and knuckle (N) can be moved vertically (B)
5 arms connected to (UP, LE, LO, TR, C
O) and a damper that buffers the vertical movement of the knuckle (N)
(D) in a multi-link suspension system, wherein the five arms (UP, LE, LO, TR, CO)
Is extended in the left-right direction of the vehicle body and is above the axle (A).
Upper arm connecting (B) and knuckle (N)
(UP) and the vehicle extends from the front inside to the rear outside of the vehicle.
Connect the body (B) and knuckle (N) above the axis (A)
And trailing arm (TR)
And below the axle (A), with the body (B) and knuckle (N)
The lower arm (LO) that connects the
It extends outside the front of the body and extends below the axle (A) and the vehicle body (B).
Leading arm (LE) that connects with the kuckle (N)
And extending in the left-right direction of the vehicle body and in front of the axle (A)
Control arm that connects (B) and knuckle (N)
And trailing arm (TR)
Front-to-back distance of upper arm (UP) outer edge to edge
(L_U) To the outer end of the trailing arm (TR)
The front-back distance of the outer end of the control arm (CO)
(L _U′) Is set to a large value and the reading
Before the outer end of the lower arm (LO) with respect to the outer end of the arm (LE)
Backward distance (l_L) Than the leading arm (L
E) In front of the outer end of the control arm (CO) with respect to the outer end
Backward distance (l_L′) Is set large
Multi-link suspension system.