Patent ID: 7500410

Claim:
A transmission for a tractor comprising: a change speed device operable, when an engine of the tractor and said transmission are connected, to transmit, in varied speeds, power from said engine to driving wheel; a main drive shaft for receiving the power from said engine when the engine of the tractor and the transmission are connected; and a reverse and forward drive switching device adapted to be disposed between said engine and said change speed device when the engine of the tractor and the transmission are connected and operable to switch a direction of rotation of the power from said engine, said reverse and forward drive switching device being shiftable between a high-speed forward drive position, a low-speed forward drive position, and a reverse drive position, and including: a high-speed forward drive clutch mounted to said main drive shaft for switching said reverse and forward drive switching device to the high-speed forward drive position; a low-speed forward drive clutch mounted to said main drive shaft for switching said reverse and forward drive switching device to the low-speed forward drive position; and a reverse drive clutch mounted to said main drive shaft for switching said reverse and forward drive switching device to the reverse drive position; a first input gear; a second input gear; a high-speed forward drive output gear meshed with said first input gear for receiving forward drive through the high-speed forward drive clutch, and transmitting high-speed forward drive to the change speed device; a low-speed forward drive output gear meshed with said second input gear for receiving forward drive through the low-speed forward drive clutch, and transmitting low-speed forward drive to the change speed device; and a reverse drive transmission gear meshed with one of said first input gear and said second input gear for receiving reverse drive through the reverse drive clutch, and transmitting reverse drive to the change speed device.