In the automotive industry, it is desirable to lock the steering shaft of a vehicle in place to prevent rotation of the steering shaft when the vehicle is not in use. Known systems utilize a keyed ignition system associated with the steering column. When the key is removed from the ignition, a steering shaft lock mechanism may be actuated to lock the steering shaft in place. Other vehicles utilize a keyless system or a system where the keyed ignition system is not associated with steering column. For these configurations, a separate actuator may be used to lock and unlock the steering shaft.
In one known steering shaft lock actuator, a locking member may be moved by the actuator from an unlocked to a locked position. When in the locked position, the locking member may engage a recess in the steering shaft to lock the steering shaft. The recess may be formed by adjacent teeth of a toothed ring that may be coupled to the steering shaft. An obstruction, e.g., a tooth of the toothed ring, may be encountered as the actuator attempts to drive the locking member to the locked position. The actuator motor may remain energized so that the motor drives the locking member to the locked position when the obstruction is removed. This can stress the motor and lead to early failure of the actuator. Actuator failure may be manifested in a failure of to lock the steering shaft when the vehicle is not in use and/or inadvertent locking of the steering shaft during normal driving conditions, which, of course, would pose a critical safety hazard.
Accordingly, there is a need in the art for a steering shaft lock actuator configured to protect the actuator if an obstruction is encountered when the actuator attempts to drive the locking member toward a locked position and there is a need for a reliable steering shaft lock actuator to protect against inadvertent locking of the steering shaft during normal driving conditions.
Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended that the claimed subject matter be viewed broadly.