Effects of Tool Errors on Face-hobbed Hypoid Gear Mesh and Dynamic Response

The tooth surface error will affect the contact pattern and transmission error of the hypoid gear, which may result in an unfavorable dynamic response. The tooth surface error can be generated by machine tool errors, such as blade wear. The most common forms of blade wear are the positive cutter radius and the positive blade angle error. In addition, in the cutting process of face-hobbed hypoid gear, the continuous indexing motion will aggravate the blade wear due to the alternating cutting force. Most previous studies on the influence of hypoid gear tool errors only focus on the contact pattern and static transmission error. However, there are very few studies about the effect of tool errors on hypoid gear dynamic responses. In this paper, a hypoid gear tooth surface, mesh, and linear dynamic model with tool errors were established. The tooth surface deviation distribution of different tool errors was analyzed. The effective mesh parameters such as time-varying mesh points, line-of-action, mesh stiffness, and transmission error harmonics are calculated for different cutter radius errors and blade angle errors. The dynamic transmission error and mesh force are also analyzed to evaluate the hypoid gear vibratory responses. The simulation results show the negative cutter radius error and positive blade angle error will increase the dynamic responses of hypoid gear. The influence is more obvious under the high torque.