Automobile steer-by-wire steering system has mechanical steering mechanism brought into operation upon failure of steer-by-wire system

摘要

The steering system has an electronic regulator (23) for regulation of a steering setting drive (5) for the steered wheels (1) in dependence on the position of a manual steering wheel (11), together with a resistance force device (12) coupled to the steering wheel, for simulating mechanical steering. The correct function of the steer-by-wire system is monitored for switching to mechanical steering by closing a normally open coupling (6) between the steering wheel and a mechanical steering mechanism (3,4,10). A sleeve is positioned coaxial to the coupling and displaced helically for transmission of the closure force by a spring bias, with an electric motor holding the sleeve in the open coupling position during normal function of the steer-by-wire system.