Drive train with a single diametral pitch pinion driving two gears with different diametral pitches

摘要

A marine propulsion unit drive train including two oppositely facing driven bevel gears having a common rotational axis and different numbers of teeth engaged with a bevel pinion drive gear having a single diametral pitch. Both driven gears have the same pitch diameter but different diametral pitches so that the driven gears rotate at different rates to boost performance when the propulsion unit is operated. The drive train is applicable to single propeller marine propulsion units and dual propeller stem drive units, and a method for fabricating a reduced-tooth driven gear to mesh with a drive pinion of a different diametral pitch is disclosed.