Power train for two-wheel tractor

摘要

An off-highway vehicle having a tractor section and a trailing section each having a pair of ground engaging wheels. The tractor section has an axle assembly with aligned front and rear pivot connections defining a roll axis, with a spring suspension device being interposed between the rear pivot connection and the tractor section to accommodate relative movement. The tractor section has an engine mounted at the rear and a transmission at the front, with a main drive shaft extending from the transmission to the axle and having universal joints at its ends. The forward pivot connection of the axle assembly is positioned substantially midway of the universal joints for equal angular deflection at the joints upon a given amount of relative vertical movement of the tractor axle. In the preferred embodiment the trailing section has an axle assembly including a pair of laterally spaced forwardly projecting tongues providing rigidity about a fore-and-aft roll axis, rolling rigidity also being provided between the two sections of the vehicle, so that the tractor section tilts in accordance with lateral tilt of the wheels of the trailing section, while the tractor axle assembly is free to undergo relative movement about its roll axis in the following of ground contours.