lead screw

A leadscrew is screw specialized for the purpose of translating rotational to linear motion. The mechanical advantage of a leadscrew is determined by the screw pitch or lead.A leadscrew nut and screw mate with rubbing surfaces, and consequently they have a relatively high friction and stiction compared to mechanical parts which mate with rolling surfaces and bearings. Their efficiency is typically only between 25 and 70%, with higher pitch screws tending to be more efficient. A higher performing, and more expensive, alternative is the ball screw.
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