Tooth profile generation method of involute and cycloid combined tooth profile

The invention discloses a tooth profile generation method for an involute and cycloid combined tooth profile, which comprises the following steps of: fitting two curve sections of which the curvature is less than the minimum curvature without undercutting in a transmission ratio curve by utilizing a Fourier function, and connecting the two curve sections end to end by utilizing a polynomial curve to obtain the transmission ratio curve; after the pitch curve coordinates of the driving non-circular gear and the driven non-circular gear are calculated, cycloid tooth profiles are adopted for the tooth crest part outside the pitch curve of the driving non-circular gear and the tooth root part inside the pitch curve of the driven non-circular gear, and involute tooth profiles are adopted for the tooth root part inside the pitch curve of the driving non-circular gear and the tooth crest part outside the pitch curve of the driven non-circular gear; the tooth crest profile and the tooth root profile of the driving non