Research On New Type Of Synthesis Method For Movable Teeth Transmission Based On Cam Mechanism

The movable-teeth-drive which is derived from the planetary gear with small tooth difference problems has two limits :the deduction of tooth profile is too complex and the theory is dispersive.This paper proposes a linkage-cam mechanism from the transmission rule of cam mechanism based on its characteristics of diversity,introduces the transmission principle,and explains the transmission principle of the movable-teeth-drive mechanism from the perspective of linkage-cam mechanism.This paper puts forward a new method to design tooth profile which is much easier than the method of solving envelope curves.The design method of linkage cam mechanism are derived on the profile equation of center-straight-push-rod movable teeth drive mechanism and indirect conjugate for two type of asymmetrical teeth profile is proved,summarizes the general condition of the indirect conjugate.The relationship among the number of movable teeth,the number of teeth of the shock wave and the number of teeth of the center wheel is deduced,and the feature that movable teeth should distribute uniformly is proved.The transmission ratio of the new type of movable teeth drive is derived by using the relative angular velocity method and the angle analysis method.Based on the design of the conjugate tooth profile equation.The general steps of the design of the non conjugate teeth profile equation are presented.The relationship between the shock wave and the center wheel and the limiting conditions of the continuous meshing are given.The analytic formula of curvature and pressure angle are deduced based on the tooth profile formula,and the influence parameters are given through the simulation of specific profile analysis,such as teeth number,push stroke,the ratio of the lift and return range,the radius of the base circle and teeth profile law.The dimension parameters of parts are determined based on the theoretical research.CAXA and Pro/E are combined to complete the virtual assembly,and the motion simulation of two kinds of asymmetric teeth profile transmission mechanism is carried out which is verified by the uniform and non-uniform speed.