Springs - Torsion bars and stabilizers

The torsion bar is the simplest of all springs whose material works under torsion. It is generally made in the form of a solid or hollow cylindrical bar, but there are also torsion bars with a non-circular cross-section and, in particular, rectangular bars generally bundled together to form laminated bars.

Stabilizers are springs used in vehicle suspension systems in the same way as load-bearing springs.

There are two main causes of disruption to the movement of spring-supported vehicles:

• on the one hand, the irregularities of the track they travel on;

• centrifugal forces due to cornering.

These two types of disturbance modify the load distribution between the two wheels on the same axle, causing the vehicle to oscillate sideways around its longitudinal axis. These oscillations are reduced when the suspension is fitted with springs with variable or double flexibility and, on heavy-duty vehicles, by the use of compensating springs.