Includes threaded rider mating with support screw in drive means:
(under subclass 250) Drive-means* including (a) an element attached to the load-underlying support surface of the elevator which has an aperture therein with an internally facing threaded tooth and (b) a cylindrical rod passing through the aperture and mounted along the length of the shaft* which has a tooth on its outer surface threaded around the longitudinal axis of the rod and mating with the tooth of the element, and rotating relative thereto, when power is transmitted to the load-underlying support surface to shift it along the shaft*.
SEE OR SEARCH CLASS
254, Implements or Apparatus for Applying Pushing or Pulling Force,
