Multi-speed worm gear reduction assembly

摘要

A gearbox assembly including a housing supporting an input shaft to drive a first shaft that includes drive gears that correspond to driven gears on a second shaft. The driven gears are movable axially along the second shaft by shift levers such that a desired gear ratio can be selected. The second shaft also includes a worm shaft portion that drives a corresponding worm gear disposed on an output shaft. Another embodiment includes an input shaft driving first and second shafts. A third shaft includes two clutch assemblies with driven gears that engage drive gears of the first or second shafts. A gear on the third shaft drives a gear of an output shaft. The clutch assemblies move one of the driven gears into engagement with one of the first and second drive gears to selectively vary the speed of the output shaft.