Abstract: Aiming at performance requirements such as low inertia, high stiffness, high precision and small backlash of precision transmission device with high-speed input, the two-stage double crank adjustable backlash planetary reducer with external gears parallel moving and internal gear output is proposed on the basis of involute beveloid gears. According to the characteristics of involute beveloid internal gear pair with few teeth difference, mechanical analyses of key components such as planetary gear, turning arm bearing and support bearing are carried out, the corresponding mechanical analysis models are built, and the corresponding analyses and calculations are accomplished. Simulation modeling and calculation of the involute beveloid planetary gear transmission are completed in ADAMS. The analyses indicate that the weak links of the new-type involute beveloid planetary gear transmission is turning arm bearing and supporting bearing. The parametric analysis model is built, and relevant influencing parameters such as the center distance, axial distance of the bearings and the number of planetary gears are analyzed. For the said weak links, in the permission of the space in the transmission device, increasing the center distance of turning arm bearing and the axial distance of support bearings can greatly decrease the loads of the both bearings.

Key words: Adjustable backlash, Double crank planetary transmission, Involute beveloid gear