A direct method for determining meshing surfaces of globoidal cams with tapered roller followers

Abstract

Abstract

For determining the globoidal cam profile with tapered rollers radially mounted at its turret, a direct and relative simple approach is presented. The concept of the proposed procedure is based on the cam surfaces that can be represented as the swept surfaces of the tapered roller of the globoidal cam-turret mechanism in motion. For finding the swept surfaces of the tapered roller, the pitch surface yielded by the locus of the tapered roller is first generated through the rigid body transformation. Then, in the process of producing the swept surfaces for the cam surfaces, the meshing angles and meshing vectors are defined and identified by using the pitch surface of the tapered roller. Since it is not necessary to solve any non-linear contact equations usually encountered in traditional methods, such a procedure provides a convenient tool in determining the spatial cam surfaces. To demonstrate the feasibility and accuracy of the proposed approach, its analytical formulations with numerical results are compared with those obtained by an earlier technique based on the theory of screws.