Transmission system for working vehicles

An improved working vehicle including a frame, an engine mounted on said frame, said engine including an engine output shaft which extends towards a rear of said frame, a first and second rear wheel disposed outside of said frame at opposite sides of the rear of said frame and rotatably mounted on first and second axles respectively, wherein the improvement comprises:

• a transmission assembly for transmitting the power of said engine to said first and second rear wheels with a continuously variable speed, said transmission assembly including:
• a first hydrostatic transmission disposed at one of said transverse sides of the rear of said frame proximate the first rear wheel and a second hydrostatic transmission disposed at the opposite transverse side of said frame proximate the said second rear wheel, each of said hydrostatic transmissions including a transmission input shaft which extends from said hydrostatic transmission towards the rear of the vehicle a transmission output shaft which extends from said hydrostatic transmission away from the rear of the vehicle said, and
• control shaft extending from said hydrostatic transmission of the vehicle for controlling the transmission ratio of said hydrostatic transmissions;
• a first L-shaped gear box secured to said first hydrostatic transmission and a second L-shaped gear box secured to said second hydrostatic transmission, each of said gear boxes extending over front and outer side of the hydrostatic transmission to which it is secured, and wherein said transmission output shafts lie in a first plane, said axles lie in a second plane substantially the same as said first plane, a length of said engine output shaft lies in a third plane parallel to and separate from said first plane and said transmission input shafts lie in a fourth plane parallel to and between said first and third planes said transmission output shaft of said first hydrostatic transmission extending into the first gear box, said transmission output shaft of said second hydrostatic transmission extending into said second gear box, said first axle being journaled in said first gear box, said second axle being journaled in said second gear box, each of said gear boxes including therein:
• a rotatable, intermediate shaft extending parallel with said transmission output shaft,
• a first reduction gear train having a first spur gear fixedly mounted on said transmission output shaft and a second spur gear mounted on said intermediate shaft, said second spur gear meshing with said first spur gear,
• and a second reduction gear train having a first bevelled gear fixedly mounted on said intermediate shaft and a second bevelled gear mounted on the wheel axle, said second bevelled gear meshing with said first bevelled gear;
• and
• transmitting means for drivingly connecting the engine output shaft with the transmission input shafts of said pair of hydrostatic transmissions and wherein said transmission output shafts lie in a first plane, said axles lie in a second plane substantially the same as said first plane, a length of said engine output shaft lies in a third plane parallel to and separate from said first plane and said transmission input shafts lies in a fourth plane parallel to and between said first and third planes.