Position servo systems

Abstract

A position servo system exemplified by a power-assisted steering system in which a power-driven continuously-variable-ratio transmission ("CVT") of the variable-ratio-epicyclic type, and particularly of the toroidal-race rolling-traction type, is arranged coaxially with the wheel or other rotary actuating member and the steering or other driven mechanism, and delivers an output to augment the steering effort in response to an error between the positions of the actuating member and the steering mechanism. Mechanisms described to prevent interference with the normal manual connection between the actuating member and the steering mechanism should the CVT cease to rotate, and on occasions when the normal sense of operation is reverse and the steering mechanism tends to steer the actuating member. Mechanisms are also described, where the CVT is of the toroidal-race type, to ensure quality between the forces exerted on the steering mechanism by all its connections with the CVT.

Dependencies are inferred from the claim text.