Suspension (vehicle)
|
|
af:Veringstelsel de:Federung ja:サスペンション
Suspension is the term given to the system of shock absorbers and linkages which connect a vehicle to its wheels. Suspension systems serve a dual purpose - keeping a car's wheels on the ground where they can provide traction, and keeping vehicle occupants comfortable and reasonably well isolated from road noise, bumps, and vibrations. These goals are generally at odds, so the tuning of modern suspensions is often finding the right compromise. Design of front and rear suspension of a car is different.
| Contents |
Springs and dampers
All suspensions use springs to absorb impacts and dampers (or shock absorbers) to control spring motions. A number of different types of each have been used:
Springs
- Leaf spring - AKA Hotchkiss, Cart, or semi-elliptical spring
- Torsion beam
- Coil spring
- Rubber bushing
Dampers
- MacPherson strut
- Chapman strut
- Shock absorber - AKA damper
- Coilover
Suspension types
Suspension systems can be broadly classified into two subgroups - dependent and independent. These terms refer to the ability of opposite wheels to move independently of each other.
A dependent suspension normally has a live axle (a simple beam or 'cart' axle) that holds wheels parallel to each other and perpendicular to the axle. When the camber of one wheel changes, the camber of the opposite wheel changes in the same way.
An independent suspension allows wheels to rise and fall on their own without affecting the opposite wheel. In this case, the wheels are either not connected at all or are connected through universal joints with a swing axle.
A third type is a semi-dependent suspension. In this case, a swing axle is used, but the wheels are also connected with a solid tube, most often a deDion axle.
Dependent suspensions
Dependent systems may be differentiated by the system of linkages used to locate them, both longitudinally and transversely. Often both functions are combined in a set of linkages.
Examples of location linkages include:
Independent suspensions
The variety of independent systems is greater and includes:
- Swing axle
- deDion axle
- MacPherson strut/Chapman strut
- Wishbone
- Multi-link
- Torsion beam
- Semi-trailing arm
New suspension technologies in development include a system from the Bose Corporation which uses computer-controlled motors to automatically adjust the suspension to changing road surfaces, keeping a vehicle level and in contact with the road even at high speed over bumpy roads, or in hard cornering.
External links
- The Suspension Bible (http://www.chris-longhurst.com/carbibles/suspension_bible.html)
- Bose Suspension System (http://www.bose.com/learning/project_sound/suspension_challenge.jsp)