Differential drive mechanism

A differential drive mechanism for automotive vehicles, comprising:

• a support casing mounted on a body structure of the vehicle;
• an input shaft rotatably carried on said support casing to be driven by drive torque applied thereto;
• a rotary housing rotatably mounted within said support casing and being in drive connection with said input shaft, said rotary housing forming a sealed cylindrical chamber therein;
• a pair of split drive axles each arranged coaxially with the rotational axis of said rotary housing for drive connection to a set of road wheels and being rotatably carried by said rotary housing for relative rotation;
• a pair of axially spaced pistons slidably disposed within the sealed cylindrical chamber of said rotary housing to be axially inwardly moved by a thrust force applied thereto;
• a pair of axially spaced clutch assemblies disposed between said pistons for transmitting the drive torque from said input shaft to said drive axles when engaged by axially inward movement of said pistons;
• an intermediate element disposed between said clutch assemblies for applying the thrust force acting on one of said clutch assemblies to the other clutch assembly;
• and
• a pair of rotary members disposed within a pair of annular cavities formed between said pistons and the opposite end walls of said sealed cylindrical chamber and being mounted on said drive axles for rotation therewith, said rotary members each having at least one radial blade which is slidably engaged with said respective pistons and said respective end walls, and said annular cavities each being filled with a viscous fluid.