Abstract：A herringbone face-gear drive was developed in this project. The design of the herringbone face-gear geometry used the entire tooth surface precise modeling method. A geometry shaper was modeled mathematically with a precise, three-dimensional mathematical model then developed for the herringbone face-gear pairs. The loaded tooth contact analysis (LTCA) method was used to analyze the characteristics of the herringbone face-gear drives, including the tooth contact area, the axial force on the pinion gear, the contact ratio, the transmission error, the effect of the inner and outer face widths, and the effect of the inner and outer tooth phases. A numerical study shows that the advantages of herringbone face-gear drives include no axial force on the pinion, simplified bearing support, larger transmission ratios, larger helix angles, higher bearing capacities, less vibration and noise, high-speed applications, high-load applications, lower sensitivity to the sense of rotation, and being applicable to both clockwise and counterclockwise rotations. Finally, this paper summarizes the design rules for herringbone face-gear drives.
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