Sovella workbench

My proposal for Sovella workbench is to use a double threaded bushing (left and right). Within one 360 deg. rotation, vertical displacement will be doubled - optional accessories can be added if the price is not a problem. - left and right sides are linked with chain wheels and drives. - for a complete stroke are needed about 26 spins for M48 thread with pitch P=8 mm - for maximum load 500 kg the force needed is about 150 N - approximate time for a complete movement is one minute - chain can be covered with metal case plate / sheet