Torsional Stiffness Calculation of Double-Enveloping Cycloid Drive

Abstract

On a gear tooth surface, there may be some certain points which contact twice with its mating gear tooth surface. This phenomenon is called secondary action. In this paper, applying this phenomenon in cycloid drive, a new type of double-enveloping cycloid drive is generated based on gear geometry theory, and the torsional stiffness is calculated. The new conjugated tooth profile is composed by an external cycloid tooth profile and a new generated internal ring gear tooth profile. The main characteristic of the new tooth profile is that there are double contact lines simultaneously between on tooth pair in a certain meshing area. In this paper, firstly the generation method of the new conjugated tooth profile is present, and the meshing characteristics are investigated. Secondly, the torsional stiffness calculation model for double-enveloping cycloid drive is established. The normal stiffness, the arm length of the meshing force and the torsional stiffness are calculated. Finally, based on a numerical example, the calculation results are present, and the torsional stiffness of double-enveloping cycloid drive is compared with that of the conventional cycloid drive both on single tooth pair and whole gear mesh.