Self-contained electric axle for all-wheel drive

An all-wheel drive motor vehicle having an internal combustion engine (10) for propelling the motor vehicle while dissipating waste energy during operation, the all-wheel drive motor vehicle comprising:

• a first driveline (12) for transferring torque between a first pair of wheels (16a, 16b), the first driveline (12) including a self-contained drive axle assembly (35) including an electric motor (18) for propelling the motor vehicle mounted coaxial with and sheathing a first portion of the drive axle assembly (35), a disconnect clutch (20) mounted coaxial with and sheathing a second portion of the drive axle assembly (35) for selectively connecting powered rotation of the electric motor (18), and a gear box (14) connected to the disconnect clutch (20), the gear box including a transmission (15) and a power take off unit (40), the gear box mounted coaxial with and sheathing a third portion of the drive axle assembly (35), the transmission for selectively transferring powered rotation from the internal combustion engine (10), the electric motor (18), and a combination of the internal combustion engine (10) and the electric motor (18) through the drive axle assembly (35), the power take off unit (40) for transferring powered rotation from the drive axle assembly (35);
• a second driveline (36) for transferring torque between a second pair of wheels (38a, 38b), the power take off unit (40) transferring rotary power from the first driveline (12) to the second driveline (36);
• a power supply system (22) for recovering waste energy dissipated by the motor vehicle during normal operation, converting the waste energy to electrical energy for rotating the electric motor (18), and storing the electrical energy;
• and
• a control system (24) having at least a first and second vehicle sensor (26a, 26b) and an electronic control unit (28), the first vehicle sensor (26a) for detecting a rotary speed of the electric motor (18) and the electronic control unit (28) for selectively controlling the disconnect clutch (20) when the rotary speed detected by the first vehicle sensor (26a) exceeds a threshold speed, the second vehicle sensor (26b) detecting operating characteristics of the motor vehicle and the electronic control unit (28) for selectively controlling actuation of the electric motor (18) in response to the second vehicle sensor (26b).

A method of assembling a driveline (12) for a motor vehicle comprising:

• assembling a self-contained drive axle assembly (35) to be connected extending between a first pair of wheels (16a, 16b) including:
• mounting an electric motor (18) coaxial with and sheathing a first portion of the drive axle assembly (35) for propelling the motor vehicle;
• connecting a disconnect clutch (20) coaxial with and sheathing a second portion of the drive axle assembly (35) for selectively connecting powered rotation between the electric motor (18) and a gear box (14);
• and
• positioning the gear box (14) including a transmission (15) and a power take off unit (40) coaxial with and sheathing a third portion of the drive axle assembly (35), the transmission for selectively transferring powered rotation to the first pair of wheels (16a, 16b) through the drive axle assembly (35), the power take off unit (40) for transferring powered rotation from the drive axle assembly (35).