Profile Surface Construction and Pressure Angle Analysis of a New Type of Globoidal Indexing Cam

This paper presents a new type of globoidal indexing cam mechanism with steel ball. The characteristic of this mechanism has double circular arc section for cam raceway. Due to this kind of cam raceway section the mechanism can realize approximate rolling transmission. According to rotary transform tensor theory profile surface equation of globoidal cam is established. Meshing equation is built through meshing theory, and profile surface equation is determined by meshing equation. Based on profile surface equation 3D geometric model for globoidal cam is established. MATLAB software is used to calculate three-dimensional coordinate points, these coordinate points are imported into Pro/E software, and finally 3D model for globoidal cam is established by three-dimensional modeling function of Pro/E software. Pressure angle equation of globoidal cam is also established. On the condition that the other parameters remain unchanged the variation law of values of pressure angle depended on cam angle and indexing plate rotary radius is obtained respectively.