Free vibration for a two-stage sinusoidal movable tooth drive system

Abstract

Two-step sine movable tooth drive has the smallest radial and axial sizes which is especially suitable for oil drilling machine and robot arm. Undesirable dynamic performance will result in noise and unacceptable performance characteristics which should be predicted in the design stage. In this paper, the analytical model of the dynamics for a two-step sine movable tooth drive was proposed. From the model, dynamics equations of the drive system were developed. Using the equations, natural frequencies and vibration modes of the drive system were investigated. Effects of the drive parameters on the natural frequencies were analyzed. The results show that the vibrations of the two-step sine movable tooth drive include two mode types: rotational mode and movable tooth mode. Mesh stiffness between movable teeth and related elements has important effect on the dynamics performance of the drive system. For a special mesh stiffness value, mode transition could occur. Mass of the movable tooth and guide has obvious effects on the vibrations of the different elements, respectively.