  We study noncontact rack and pinion composed of a corrugated plate and a
corrugated cylinder intermeshed via the lateral Casimir force. We assume that
the rack position versus time is a periodic multi-harmonic signal. We show that
in a large domain of parameter space and at room temperature, the device acts
as a mechanical rectifier: The pinion rotates with a nonzero average velocity
and lifts up an external load. The thermal noise may even facilitate the device
operation.
