Front Suspension Description - Mazda 6 Training Manual

FRONT SUSPENSION DESCRIPTION

King-pin Ais Configuration
• The king-pin ais, depending on the type of front suspension, is as follows:
— In the strut type front suspension, wheels rotate around the king-pin ais going from the point where the
shock absorber is attached to the body (point A) to the ball joint (point B).
— In the high-mount double wishbone type front suspension (with double-pivoted lower arm(s)), wheels rotate
around the king-pin ais going from the upper arm ball joint (point C) to the imaginary pivot line (point D)
etended from the lower arm(s).
• The intersection of king-pin ais and the road surface (point E) is offset in the vehicle from the wheel setting
center point of on the road (point W), producing a king-pin offset.
• Compared to the strut front suspension, the high-mount double wishbone front suspension (with double-
pivoted lower arm(s) has the following technical advantages:
— The moment of inertia around the king-pin ais is reduced due to the short king-pin to wheel-center offset.
This feature reduces undesirable vehicle behaviour such as steering pull and judder when breaking,
smooth steering obstruction due to road conditions, and the influence of steering torque due to road
undulation.
— The king-pin offset value (negative king-pin offset) is optimized. Due to this, the influence of the ais weight
is not felt and steering control is lightened. Also, straight driving stability is improved because the toe-in
moment from the braking effort the wheels counteracts the yaw moment caused by road surface conditions
and/or the difference of right and left wheel braking effort.
Suspension system comparison
.
1 King-pin ais
2 King-pin inclination
3 King-pin offset
4 King-pin to wheel-center offset
5 Wheel center
6 Imaginary pivot
R–6
FRONT SUSPENSION
7
8
9
10
11
High-mount double wishbone front suspension
Strut front suspension (626 (GF) model)
View from horizontal ais of the vehicle
View from vertical ais of the vehicle
Front
A6E741401015T03
A6E7414T002