Parking brake interlock for automatic lift axle

摘要

An automatic air suspension control system is provided for use in combination with a vehicle having a liftable non-driven rear axle, a driven rear axle, a parking brake, and an air suspension associated with the rear axles to apply a load to the rear axles. The air suspension control system is programmed to determine whether the rear axles are subject to a load condition under which the non-driven rear axle is to be moved between lifted and deployed conditions. If the rear axles are subject to a load condition under which the non-driven rear axle is to be moved, the air suspension control system also determines whether the parking brake is engaged. If the parking brake is disengaged, then the air suspension control system causes the non-driven rear axle to be moved; otherwise, if the parking brake is engaged, then the non-driven rear axle is prevented from moving.

主权项

1. An automatic air suspension control system for use in combination with a vehicle having a non-driven rear axle configured to be moved between a lifted condition and a deployed condition, a driven rear axle, a parking brake, and an air suspension associated with the rear axles to apply a load to each of the rear axles, wherein the automatic air suspension control system is programmed to
command the air suspension to apply load to one or both of the rear axles and to move the non-driven rear axle between the lifted and deployed conditions under selected load conditions, and prevent movement of the non-driven rear axle from the lifted condition to the deployed condition when the parking brake is engaged or prevent movement of the non-driven rear axle from the deployed condition to the lifted condition when the parking brake is engaged.