JPS5855052Y2 - Trailing arm suspension system - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a trailing arm type suspension system used for vehicles such as automobiles.

It has a trailing suspension arm that is pivoted to the frame at one end so as to pivot around one axis extending in the width direction of the vehicle body, and that extends rearward from the pivot point and pivots the wheels at the other end. Trailing arm suspension systems are known.

In the above-mentioned trailing arm suspension system,
The trailing suspension arm is pivotally supported via a rubber elastic bushing for vibration isolation.

Therefore, when the lateral force acting on the wheels (tires) acts on the trailing suspension arm when the vehicle is turning, the attachment posture of the trailing arm to the vehicle body changes due to the elastic deformation of the bushing, and the direction of the wheel changes. Maneuverability and stability deteriorate at times.

Using FIG. 1, it will be specifically explained that the attachment attitude of the trailing suspension arm to the vehicle body changes when the vehicle turns.

Here, explanation will be given by taking the trailing suspension arm of the left rear wheel as an example.

In the figure, reference numeral 1 designates a trailing suspension arm, and this trailing suspension arm 1 has two pivot parts 2 and 3 spaced apart substantially in the width direction of the vehicle body at one end thereof. It is pivoted to the vehicle body, which is not shown.

The trailing suspension arm 1 rotatably supports a left rear wheel 4 at its other end extending toward the rear of the vehicle body from the pivot portion.

For example, when the vehicle turns to the right, a lateral force F as shown by the arrow in the figure acts on the left rear wheel 4.

Due to this lateral force F, a force directed toward the rear of the vehicle body as shown by Fa in the figure acts on the outer pivot part 2, and a force directed toward the rear of the vehicle body as shown by Fb in the figure acts on the inner pivot part 3. A forward force acts on the

For this reason, the bushings incorporated in each pivot are largely deflected by the force, and as a result, the trailing suspension arm 1 is displaced as shown by the imaginary line in the figure, and the trailing suspension arm 1 The left rear wheel 4 supported by the left rear wheel 4 produces a steering angle θ in a direction that strengthens the turning of the vehicle.

As described above, the conventional trailing arm type suspension system has the disadvantage that it tends to increase the degree of so-called oversteering when the vehicle turns, resulting in a decrease in maneuverability and stability when turning.

In order to compensate for the above-mentioned drawbacks, if the stiffness of the bushing is increased, the shock vibrations transmitted to the vehicle body when the vehicle rides on a bump on the road surface will increase, making the ride uncomfortable.

For this reason, in the trailing arm type suspension system, it is difficult to simultaneously improve maneuverability and stability and improve riding comfort.

In view of the above-mentioned drawbacks of conventional trailing arm type suspension systems, the present invention improves maneuverability and stability when the vehicle turns without increasing the stiffness of the bushings, thereby improving maneuverability and stability. The purpose of the present invention is to provide an improved trailing arm type suspension system that can simultaneously improve riding comfort.

According to the present invention, this purpose is to provide a pivot point at one end extending toward the rear of the vehicle body, which is pivoted to the frame so as to pivot around a design axis extending in the width direction of the vehicle body at one end. The trailing suspension arm has a trailing suspension arm that pivots the wheel by means of two separate pivots spaced apart along the design axis through rubber-like elastic bushings. This is achieved by a trailing arm type suspension system, in which the pivots located outside the vehicle body are eccentrically located below the design axis, and those located inside the vehicle body are eccentrically supported above the design axis. be done.

When a vehicle turns, the wheels on the outside of the turn are spring-compressed and move toward the vehicle body, that is, they bounce, and the wheels on the inside of the turn move away from the vehicle body, that is, they rebound.

Therefore, when the vehicle turns, the trailing suspension arm that supports the wheel on the outside of the turn pivots upward about its pivot.

Of the pivots of the trailing suspension arm, the one on the outside of the vehicle body is eccentrically located below the design axis, and the one on the inside of the vehicle body is eccentrically located above the design axis, so that the trailing suspension arm is When pivoted upwardly about their pivots, the trailing suspension arms create a steer angle in a direction that controls the turning of the vehicle.

Therefore, when the vehicle actually turns, the trailing suspension arm moves to create a steering angle in the direction that suppresses the vehicle's turning, as described above, and the trailing suspension arm is affected by lateral force, causing the vehicle to The action of moving to create a steering angle in a direction that strengthens the turning of the steering wheel is canceled out, and deterioration of maneuverability and stability is avoided.

In this way, the trailing suspension arm is affected by the lateral force and produces a steering angle in the direction that strengthens the turning of the vehicle.The pivoting of the trailing suspension arm causes the trailing suspension arm to suppress the turning of the vehicle. This is offset by producing a steer angle in the direction in which the steering wheel moves, and unnecessary steer angles are not produced in the wheels when turning, thereby preventing deterioration of maneuverability and stability.

Due to the above-mentioned effects, the stiffness of the bushing can be lowered without deteriorating the maneuverability and stability, and the ride comfort performance can be improved.

In addition, when a longitudinal force is generated in the vehicle, the sum of the translational deflection of the bushing and the rotational displacement of the bushing becomes the longitudinal displacement of the suspension system, so the longitudinal rigidity of the suspension system is significantly reduced.
The longitudinal force transmitted from the wheels to the vehicle body is alleviated.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings.

FIG. 2 is a plan view showing the essential parts of one embodiment of the trailing arm suspension system according to the present invention, and FIGS. 3 and 4 are enlarged views taken along lines ll-III and IV-IV in FIG. 2. FIG.

In the figure, 11 indicates a trailing suspension arm, and this trailing suspension arm 1
1 has at one end two mounting pieces 12, 13 spaced apart along one design axis extending in the width direction of the vehicle body.

The mounting piece 12.13 has a bearing hole 1 along the design axis.
4.15 is provided.

The bearing holes 14, 15 are each provided with bushings 16, 17 made of rubber-like elastic material.

The bushings 16, 17 each have an eccentric through hole 18, 19 through which a pivot shaft 20, 21 passes.

Pivot 20.21 Bearing pieces 23.24 and 25.2 formed on the frame (rear suspension member) 22, respectively
6 is supported.

The pivot shaft 20 on the outside of the vehicle body is provided eccentrically below the design axis, and the pivot shaft 11 on the inside of the vehicle body is provided eccentrically below the design axis.
is provided eccentrically above the design axis.

The trailing suspension arm 1 rotatably supports a left rear wheel 27 at an end extending toward the rear of the vehicle body from the pivot portion.

Next, the operation will be explained using an example where the vehicle turns to the right.

When turning to the right, the tire load acting on the left rear wheel 27, which is the outer wheel of the turn, increases, and as shown in FIGS. 3 and 4, the trailing suspension arm 11 is
Rotates clockwise in the figure with rotation centers 8 and 19.

As a result, the bushes 16 and 17 each have their centers at an angle α
move to the rotated position.

As the bushings 16, 17 move, the trailing suspension arm 11 rotates relative to the vehicle body by an angle β, as shown by imaginary lines in FIG.

Therefore, the left rear wheel 27 supported by the trailing suspension arm produces a steering angle β in a direction that suppresses the degree of turning.

At this time, the lateral force F acting on the left rear wheel 27 causes the wheel to generate a steer angle in a direction that increases the degree of turning, so the two steer angles cancel each other out, and in reality, the wheel 27
No steer angle occurs.

In this way, unnecessary steering angles do not occur in the wheels 27, thereby improving maneuverability and stability.

When the arm length of the suspension arm is 11 and the amount of bounce of the wheel is Z, the angle α is given by the following equation.

The amount of bounce Z is given by the following equation.

However, 1 =) red, ψ - roll angle The steer angle β is given by the following equation.

However, the eccentricity of the e-axis Converting the third equation above, we get becomes.

In the above, the present invention has been described in detail with respect to specific embodiments, but it will be appreciated by those skilled in the art that the present invention is not limited to this and that various embodiments are possible within the scope of the present invention. It should be obvious.

[Brief explanation of drawings]

Fig. 1 is a plan view schematically showing the displacement of the trailing suspension arm when the vehicle turns in a conventional trailing arm suspension system, and Fig. 2 is a plan view schematically showing the displacement of the trailing suspension arm when the vehicle turns in a conventional trailing arm suspension system. The plan view showing the main parts of the embodiment, FIGS. 3 and 4 are respectively taken along line II in FIG.
It is a sectional view along I-III and IV-IV. 1 - Trailing suspension arm, 2° 3 = Pivot joint, 4 - Left rear wheel, 11 - Trailing suspension arm, 12.13 - Mounting piece, 14.15 - Bearing hole,
16.17 ~ Bush, 18.19 ~ Through hole, 20.2
1 - Pivot, 22 - Frame, 23, 26 - Bearing piece, 27
~Left rear wheel.

Claims (1)

[Scope of utility model registration request] A trailing suspension arm is pivoted to the frame at one end so as to pivot around a design axis extending in the width direction of the vehicle body, and the other end extends from the pivot point toward the rear of the vehicle body to pivot the wheels. In some existing trailing arm suspension systems, the trailing suspension arm is pivoted via rubber-like bushings by two separate pivots spaced apart along the design axis; A trailing arm type suspension system characterized in that those on the outside of the vehicle body are eccentrically located below the design axis, and those on the inside of the vehicle body are eccentrically located above the design axis.