Patent ID: 7175012

Claim:
A transmission device for transmitting rotation from a primary motor shaft to an output shaft connected to ground engaging wheels for use with a self-propelled machine, the transmission comprising: an input shaft in engagement with the primary motor shaft, said input shaft having a driving member comprising a worm; an output shaft connected to at least one ground engaging wheel; a driven gear mounted on the output shaft, the driven gear comprising a clutching surface and an outer engaging surface, wherein said driven gear is moveable axially along said output shaft between a first position wherein the driven gear is freely rotatable about said output shaft and a second position; a control member configured to axially move the driven gear from the first position to the second position on the output shaft; and a projection extending from the output shaft, said projection being positioned on said output shaft such that when the driven gear is in the first position, the projection is disengaged from the clutching surface of the driven gear so as to uncouple the driven gear from said output shaft, and when the driven gear is moved to the second position, the projection engages the clutching surface of the driven gear in a locking relationship to produce a driving rotation of said output shaft by said driven gear.