High acceleration, high load and smooth running

摘要

A planetary roller screw is a rolling system consisting of a threaded shaft (screw) and a nut that, internally threaded too, contains a determined number of threaded rolls with gears on the ends. The roller engages its threads with the screw and the nut and it is guided in its orbiting motion by two timing ring gears placed at each end of the nut. The planetary roller screw is, as the ballscrew, a rolling element device but not limited by the presence of balls, typical of ballscrews. It provides more contact points within a given volume than a ballscrew, and so can be more compact for a given load capacity while providing similar levels of efficiency at low to moderate speeds, and maintaining that efficiency at high speeds. The roller screw is constructed from a screw shaft, a nut, and the planetary roller. The screw provides a helical raceway for multiple rollers radially arrayed around the nut. The rollers spin in contact with the screw and the nut. They orbit the nut when they spin. Rotation of the nut results in screw travel, while rotation of the screw results in nut travel.