Stress Analysis And Performance Experiment Of The Chord Needle Gear Reducer

Precision reducers are indispensable and crucial part of high-end machine tools,robot joints,and aerospace fields.In order to design reducers with high efficiency,high accuracy,and small size,this paper proposes a small sinusoid needle wheel reducer.It’s meshing characteristics analysis,force and stress analysis,finite element simulation analysis,prototype manufacturing,and experiments are completed.Based on the plane meshing theory,this paper establishes equations of the tooth profile,tooth profile curvature,pressure angle and slip rate of the sinusoid needle wheel reducer,and changes of the curvature,pressure angle and slip rate of the sinusoid needle wheel reducer under different tooth height coefficient,modulus and tooth number are studied.The results show that by reducing the tooth height coefficient and increasing the modulus and number of teeth,the meshing contact strength of the sinusoidal gear tooth surface and the needle tooth surface can be improved.Formulas for contact stress and bending stress of reducers are established,and the changes of contact stress and bending stress with transmission parameters are studied.The results indicate that in order to reduce the contact stress during the meshing of the sinusoid needle wheel,the tooth height coefficient can be reduced and the modulus can be increased.In order to reduce the bending stress of needle tooth,a larger tooth height coefficient,a smaller modulus,and a small number of teeth should be used.The finite element simulation software Ansys Workbench is used to complete the statics simulation of sine teeth and needle teeth.With software UG,the model design,assembly and motion simulation of each part of the sinusoid needle wheel reducer with single planet and sinusoid needle wheel reducer with double planets are realized,and the correctness of the reducer structure and the accuracy of the speed ratio are verified.The experimental platform for reducer measurement is designed and assembled,and the efficiency and backlash of sinusoid needle wheel reducer with single planet and sinusoid needle wheel reducer with double planets are tested.The results show that the maximum efficiency of the sinusoid needle wheel reducer with single planet is 55.1%,and the accuracy is 2.2316 ’;The maximum efficiency of the sinusoid needle wheel reducer with double planets is 59.12%.