Patent ID: 7883546

Claim:
A power generating leg, configured to be coupled to a person's lower limb, comprising: a thigh link; a shank link; a knee mechanism connected to said thigh link and said shank link, and configured to allow flexion and extension movements of said thigh link and said shank link relative to each other; a hydraulic torque generator configured to generate torque between said shank link and said thigh link; and a power unit configured to operate in both a power utilization mode and a power dissipating mode, said power unit including a first hydraulic path between a fluid reservoir and the hydraulic torque generator having a hydraulic motor rotatably coupled to an electric generator and a motor isolating valve connected in series, and a second hydraulic path between the fluid reservoir and the hydraulic torque generator including an actuated flow restricting valve; wherein when said power unit is in a power utilization mode, said motor isolating valve is in an open position and said hydraulic motor is powered by the electric generator and actuates the hydraulic torque generator to create a torque between the thigh link and the shank link; and wherein when said power unit is in a power dissipation mode, said motor isolating valve is in a closed position and said actuated flow restricting valve restricts fluid flow between the hydraulic torque generator and the fluid reservoir and causes the hydraulic torque generator to resist motion of the thigh link and shank link with respect to one another.