CHANGE-SPEED APPARATUS FOR A TRACTOR

摘要

A change-speed apparatus for transmitting engine power to a set of driving wheels of a tractor via a main change-speed mechanism, an auxiliary change-speed mechanism and a forward-and-reverse travel selector mechanism. The mechanisms are arranged in series in a fore-and-aft direction of a transmission case of the tractor and a shifter lever for the selector mechanism is disposed in juxtaposition to a main change-speed lever for the main change-speed mechanism. Potentially dangerous high speed shifting in either a forward or reverse direction is prevented by a restraining mechanism that automatically inhibits simultaneous shifting of the main changespeed mechanism to the highest speed, the forward-and-reverse travel selector mechanism to reverse and the auxiliary changespeed mechanism to a high speed range.