A hybrid electric vehicle drive system or transaxle 10 including an internal combustion engine 12, a generator/motor 14 which is coupled to engine 12 by use of a planetary gear set 20, and an electric motor 16. Drive system 10 includes a brake or clutch as...

The primary shaft (3) is integral with the rotor (20) of the electrical motor (2) and can cooperate with the crankshaft (10) of the IC engine (1) via a system of jaw clutching (5,6,7). The jaw clutching is controlled by a piston (8) integral in rotation wi...