Study on planetary roller screw - Comparison of static stiffness and vibration with ball screw.

A ball screw and a planetary roller screw, which accommodate rolling elements between the screw shaft and the nut, have high efficiency. It is generally said that the planetary roller screw has advantages over the ball screw about static stiffness and vibration. It is the purpose of this study to compare static stiffness and vibration of the planetary roller screw with those of the ball screw of the same size experimentally. As a result, it is clarified that the static stiffness of the planetary roller screw is 50% larger than that of the ball screw and that the vibration of the planetary roller screw is larger than that of the ball screw because the planetary roller screw has gear system.