Collapsible Steering Column (8/99) [2019-2022]: Description

The collapsible steering column is designed to collapse during a frontal collision in order to reduce driver injuries. The steering column can collapse in two areas: Its steering shaft can collapse, and the steering column can collapse toward the instrument panel.

The steering shaft consists of two tubes. The outer tube can slide over the inner tube in the event of a crash. This enables the lower portion of the steering shaft, together with the steering gear, to move upwards in a crash without pushing the steering column into the passenger compartment.

The collapsible steering column is equipped with a steel deformation plate that bends and allows the upper parts of the steering column to collapse towards the instrument panel. When the steering column and the steering wheel collapses towards the instrument panel, the impact force on the driver is lower.

Dual stage collapsible steering column 

For a dual stage collapsible steering column, the deformation plate is slotted to provide two force levels. The first stage uses the entire deformation plate. When the entire deformation plate is used, more force is needed to bend it. The second stage is triggered by an igniter mounted inside the collapsible steering column. The pin in the center of the igniter is mounted between the steering column casing and the deformation plate. When the igniter is activated, the pin drops down and only the side portions of the deformation plate is used. The amount of force needed to collapse the steering column is therefore lower.

Courtesy of VOLVO CARS CORPORATION