Collapsible Steering Column Relies on Tolerance Rings

Steering columns connected to hardware mounted in the front of the vehicle can be hazardous. In front-end crashes, for instance, the column can be forced into the driver’s chest, causing death.

To reduce the risk of this happening, Ididit, Tecumseh, Mich., a firm that makes steering columns for hot rodders and the aftermarket, worked with USA Tolerance Rings, Pennington, N.J., to design and construct a collapsible steering column. The resulting design is still made with 16-gauge tubing, so there is no need to select and test new materials. The column is now a two-piece component with a flanged tolerance or collapse ring fitted between the two tubes. The outer tube holds the ring while the inner tube slips axially inside it.

When the column load reaches 550 lb ±100 lb, the inner tube slides inside the outer tube, thus protecting the driver. And the column collapses at the target load despite changes in temperature and minor imperfections in the tube.

The column resists corrosion and will work reliably throughout its life, says the manufacturer. In addition, columns can be chrome plated or powder coated, and neither affects the collapse ring’s performance.