REAR SUSPENSION SYSTEM GENERAL GENERAL

  1. OUTLINE

    1. A torsion-beam type suspension is used.

    2. Through the optimal specification of components, the rear suspension offers excellent ride comfort and stability.

    3. The rear axle carrier bushes are obliquely mounted to obtain a toe-correction function, thus providing excellent driving stability and ride comfort.

      X116950C01

      *1

      Rear Suspension Support

      *2

      Rear Shock Absorber Assembly

      *3

      Rear Axle Carrier Bushing

      *4

      Axle Beam (Rear Axle Beam Assembly)

      *5

      Trailing Arm (Rear Axle Beam Assembly)

      *6

      Rear Coil Spring

      Note:

      Be sure to use the jack-up points that are provided on the body when raising the vehicle with a jack. Never place a jack under the axle beam (rear axle beam assembly), spring seats, trailing arm (rear axle beam assembly), or bushings of the rear suspension.

  2. MAIN FEATURES

    1. Camber Change

      1. In a torsion-beam type suspension, the camber angle and the toe change differ between bound and rebound, offering both straight-line stability and excellent cornering stability.

      2. As with full-trailing arm type suspension, the axis that joins the center of the right and left rear axle carrier bushings in the trailing arms (rear axle beam assembly) is the center of movement during any travel in the same direction.

      3. If a difference in suspension travel is created between the right and left wheels, the axle beam twists with its shearing center as the center of its rotation. Also, the changes in the camber angle in relation to the suspension travel are determined by the ratio of the distance between the bushing in the trailing arm, the axle center and the shearing center ("α" in the figure below) and distance between the bushing in the trailing arm and the axle center ("L" in the figure below). Consequently, through the optimal placement of the axle beam, the changes in the camber angle in relation to the suspension travel have been optimized, thus ensuring excellent cornering performance.

        X105964C02

        *a

        Bound

        *b

        Rebound

        *c

        Shearing Center

        *d

        Center of Rear Axle Carrier Bushings

        *e

        Instantaneous Rotational Axis of Right Axle

        *f

        Camber Change Rate α/L

    2. Anti-lift Geometry

      1. Lifting of the rear end of the vehicle during braking occurs due to the shifting of the center of gravity caused by inertia. The intersecting point (OR) supports the braking force (BF), and generates a force (BF1) in the direction of the intersecting point (OR) and a component force (BF2) in the direction of the ground contact. The force (BF1) can change the height of the intersecting point (OR). When the intersecting point (OR) is set high, it acts in the opposite direction (-▲W) of the load fluctuation (W) in order to restrain the lift.

        X116951E01
    3. Toe-correction Function

      1. The longitudinal and lateral forces that are created by the vehicle during cornering cause the rear axle carrier bushings in the trailing arms (rear axle beam assembly) to deform. In a right turn, the right trailing arm (rear axle beam assembly) moves forward and the left trailing arm (rear axle beam assembly) moves rearward, creating a tendency for the left wheel to toe-out. In this situation, the rear axle carrier bushings that are installed in the trailing arms (rear axle beam assembly) are designed to utilize the lateral force, which is applied to the bushings during cornering, to correct the left trailing arm (rear axle beam assembly) towards the toe-in direction.

        X105966C03

        *A

        Without Toe-correction Function

        *B

        With Toe-correction Function

        *1

        Rear Axle Carrier Bushings

        *2

        Left Wheel

        V100135

        Bushing Movement

        V100136

        Longitudinal Force

        V100137

        Lateral Force

        V100138

        Lateral Force Applied to the Bushing