To explore the influence of tooth on the assembly stress of flexspine, a solid element finite element model (FEM) of flexspine tooth ring with real tooth profile was established. The variation of the maximum circumferential stress with the fillet radius at tooth dedendum was analyzed, and then the optimum fillet radius was obtained to lower the maximum circumferential stress. Based on the analysis, the influence of thickness of tooth ring and width of tooth slot on the maximum circumferential stress of the flexspline tooth ring was studied. The stress influence coefficient of tooth was introduced to reveal the relationship between the maximum circumferential stress in the tooth ring and that in the ring. By considering the influence of tooth on the bending stiffness of the tooth ring, a method for calculating the magnification factor of bending stiffness based on equivalent internal force was presented, and the stress concentration coefficient was calculated numerically. The variation law of the magnification factor of bending stiffness and the stress concentration coefficient of flexspline with respect to the thickness of the tooth ring and the width of the tooth slot were obtained. Research results show that the design specification underestimates the effect of tooth on stress concentration;the stress deviation increases from 11.2% to 16.9% with the increase of tooth ring thickness, and thus the growth rate of stress with thickness of tooth ring is underestimated by the design specification. © 2020, Editorial Board of Journal of Huazhong University of Science and Technology. All right reserved.
