Abstract: A hybrid motor vehicle (10) has a four wheel drive arrangement in which the front wheels (12 and 13) are driven by the engine (11) in two wheel drive mode and all four wheels (12-15) in four wheel drive mode. The engine is connected to the rear wheels (14 and 15) through an auxiliary driveline which includes a first clutch (22) to connect to the engine (11), a propshaft (23) and a differential (25). An electric motor (28) is connected to the propshaft (23) for the purpose of driving the vehicle either with or without the assistance of the engine (11). A second clutch (27) is located between the propshaft (23) and the differential (25). When the vehicle is in two wheel drive mode, the propshaft (23) is disconnected from both the engine (11) and the rear wheels (14 and 15) and on switching to four wheel drive mode when the vehicle is moving the propshaft (23) is firstly spun up to a speed matching that of the engine (11) and rear wheels (14, 15) by the action of the electric motor (28).

Abstract: A hybrid motor vehicle (10) has a four wheel drive arrangement in which the front wheels (12 and 13) are driven by the engine (11) in two wheel drive mode and all four wheels (12-15) in four wheel drive mode. The engine is connected to the rear wheels (14 and 15) through an auxiliary driveline which includes a first clutch (22) to connect to the engine (11), a propshaft (23) and a differential (25). An electric motor (28) is connected to the propshaft (23) for the purpose of driving the vehicle either with or without the assistance of the engine (11). A second clutch (27) is located between the propshaft (23) and the differential (25). When the vehicle is in two wheel drive mode, the propshaft (23) is disconnected from both the engine (11) and the rear wheels (14 and 15) and on switching to four wheel drive mode when the vehicle is moving the propshaft (23) is firstly spun up to a speed matching that of the engine (11) and rear wheels (14, 15) by the action of the electric motor (28).