Effects of manufacturing errors on planar conjugate cams

This paper investigates the effects of manufacturing errors combined with the flexibility of the swing arm and cam surfaces for planar conjugate cams with swing followers. A three degree-of-freedom generalized model is established for analyzing the dynamic behavior so that the waviness, not the normal deviation, is found to be the dominating factor in inducing vibration, noise, fatigue and cam torque fluctuation. The normal deviation has comparatively less influence on cam dynamics that the waviness. This implies that a loose tolerance can be permitted if the surface waviness is adequately controlled. Moderate amount of normal deviation with a well-controlled waviness specification will reduce the tendency to jump. The study also demonstrates that the traditional acceleration and torque factors are still reliable when we design conjugate cams.