Non-circular gear transmission mechanism with variable-involute and variable-cycloid composite tooth profile

Non-circular gears with small curvature radius pitch curve are often used in the mechanical transmission of special motion path, but this kind of non-circular gear produces serious undercutting. Therefore, this research presented a kind of variable-involute and variable-cycloid composite tooth profile (VIVC-CTF). A transmission ratio curve of non-circular gear was designed by using Fourier function. The tooth profile equation of VIVC-CTF and its conjugate tooth profile equation were constructed on the basis of the normal and envelope methods. The influence of slip coefficient and ellipse eccentricity on the VIVC-CTF was investigated, and the variation of slip coefficient and eccentricity on the meshing line length, theoretical contact ratio, and pressure angle at pitch curve was analyzed. The meshing experiment of the VIVC-CTF non-circular gear transmission mechanism was carried out on the basis of high-speed camera technology. The theoretical results of the transmission ratio were consistent with the experimental results.