The two profiles (sides) of a gear tooth are functionally different for most gear drives. The workload on one profile is significantly higher and/or is applied for longer periods of time than for the opposite one. The design of the asymmetric tooth shape reflects this functional difference.

Benefits:

The design intent of asymmetric gear teeth is to improve the performance of the primary contacting profile by degrading the performance of the opposite profile. The opposite profile is typically unloaded or lightly loaded during relatively short work period. The "improved performance" of the primary profile provides:

The degree of asymmetry and drive profile selection for these gears depends on the application. Asymmetric profiles make it possible to manage tooth stiffness and load sharing while keeping a desirable pressure angle and contact ratio on the drive profiles.

Applications:

Gears with asymmetric teeth should be considered for gear systems that require extreme performance like aerospace applications. They are also applicable for mass production transmissions where the share of the tooling cost per one gear is insignificant, like in automotive gears. The most promising application for asymmetric profiles is with molded gears and powder metal gears. Molded gears require custom tooling anyway and asymmetric tooth profiles do not increase the tooling or production costs.

Using the direct design approach for asymmetric gear teeth is easier than for conventional gears. Asymmetric gear design is not constrained by standardized tooling and the tool based design approach used for conventional gears.

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