Drive unit for a vehicle with a continuously variable transmission

A vehicle drive assembly including:

• motor means;
• at least a pair of continuously variable ratio transmission devices, which each drive a driving wheel or a driving axle of the vehicle;
• and means for regulating said transmission devices;
• wherein each transmission device includes a planetary gear having an input shaft coupled to said motor means and an output shaft coupled to the corresponding driving wheel or driving axle, said planetary gear including three main elements, namely:
• a sun wheel;
• a planet wheel carrier provided with a plurality of planet wheels;
• and a ring gear having an inner toothing meshed with said planet wheels;
• one of said three main elements being connected to said input shaft, another being connected to said output shaft and the third acting as a reaction element;
• wherein each transmission device further includes a positive displacement pump, driven by said reaction element of said planetary gear, and a hydraulic circuit passing through said pump and provided with at least an adjustable hydraulic valve;
• wherein said regulating means are arranged to control said hydraulic valves to adjust the speed and/or the torque of said output shaft of each planetary gear;
• and wherein two points located on either side of said pump in the hydraulic circuit of each transmission device are connected to the corresponding points of the other transmission device of said pair by connecting hydraulic lines.