A special spherical surface cam with a conical roller follower and the design of its contour surface

In this paper,a special spherical surface cam with a conical roller follower is put forward. The apex of the conical roller coincides with the spherical center of the cam. Using the spherical coordinate, the author establishes the contour surface equation and pressure angle formula of the cam. The paper provides theoretical basis for the design and NC processing of the cam. The cam has the following advantageous features; (a) Its work contour surface is a developable ruled surface, and the generatrix of the surface always pass through the spherical center of the cam. So it is easy to manufacture the cam. (b)The contact line of the cam and roller is a straight line, (c) At all points on the contact line,the cam and roller are in continuous pure rolling contact,and the pressure angles are equal.