Dynamic characteristic analysis of a planetary roller screw in operating process

By taking a typical planetary roller screw as a study object, a finite element model for dynamic contact of the planetary roller screw was established. Based on the explicit dynamic finite element method, a dynamic contact analysis of the planetary roller screw was made, a fully integration element algorithm was adopted to control hourglass, the computing speed was improved by adjusting the element density and using a mixed time integration algorithm. It was concluded that the axial displacement and speed between the screw and the roller raise with increase in the rotational speed of the roller; the dynamic von Mises stresses of the contact elements on the thread teeth are basically the same at different rotational speeds of the roller; the phenomenon of loading uneven distribution exists on the whole planetary roller screw thread teeth at the same roller rotating speed; besides, the dynamic von Mises stress fluctuation of the first thread tooth is bigger than others, and the dynamic von Mises stresses of the contact elements on the screw side are bigger than those on the nut side.