Structure and tooth profile analysis of discrete teeth harmonic drive

BAI Xin, WANG Su

(School of Transportation Science and Engineering,
Beijing University of Aeronautics & Astronautics, Beijing 100191,China)

Abstract: In order to solve the problems of the poor rigidity, high lower limit of the transmission ratio and large axial size for the existing harmonic drive, the discrete teeth gear instead of the flexspline was used for the discrete teeth harmonic drive, which is the improvement for the existing harmonic drive The transmission principle and the device structure of the discrete teeth harmonic drive were introduced and analyzed The tooth profile curve equation of the rigid spline was derived based on the transmission principle and constant speed conjugate principle, and the tooth shape was given The relationship between the parameter of the tooth profile curve and the transmission properties was established, and the variation tendencies of the transmission coincidence degree and the pressure angle of rigid spline tooth profile were gotten under the influence of the parameter of the tooth profile curve, which is used to improve the transmission stability and the transmission efficiency. The results show that, under the premise of normal transmission, proper adjustment of tooth shape parameters can improve the transmission function, and it can provide the basis for the tooth profile optimization design in the future

Key words: discrete teeth harmonic drive; tooth profile; coincidence degree; pressure angle