According to the transmission principle of swing movable tooth transmission actuated by cam, the forces exerted on the movable teeth by the cam disk profile,movable teeth spar pegs and the contour of internal gear were studied with the consideration of friction forces and friction torques in the transmission.The calculation formulae of the forces exerted on the movable teeth were derived with the help of the deformation coordination equations of the swing movable tooth transmission actuated by cam. Based on the force analysis,the method used to compute the instantaneous meshing efficiency and the average meshing efficiency of the swing movable tooth transmission actuated by cam were put forward and the corresponding formulas for evaluating the efficiency were derived. A numerical example was given for illustration.The results showed that the efficiency calculation method is practical.
