Abstract: A concise mathematical model for hobbing non-circular gear is set up. Based on the point that the speeds of the hob and gear are equal along the tangent line at the cutting point, which is consistent with pure rolling between the pitch curves of the hob and gear, a group of equations is set up. The concise mathematical model for hobbing non-circular gear is obtained form the group of equations with further simplification, and it is a 3-axes simultaneous control structure. By using computer graphic simulation, the concise mathematical model is applied to demonstrate the hobbing process and result dynamically. Features of the hobbed gear can be observed from the graphics, and so become convincing basis for correct design and cutting.

Key words: Graphic simulation, Hobbing, Mathematical model, Non-circular gear