Mechanical energy storage device for hip disarticulation

Abstract

An artificial leg includes a trunk socket, a thigh section hingedly coupled to the trunk socket, a leg section hingedly coupled to the thigh section and a foot section hingedly coupled to the leg section. A mechanical energy storage device, such as a spring, is operatively associated with the artificial leg for storage and release of energy during a normal walking stride of the user. More particularly, energy is stored in the mechanical energy storage device during a weight-bearing phase of the walking stride when the user's weight is on the artificial leg and energy is released during a phase of the normal walking stride, when the user's weight is removed from the artificial leg. The stored energy is released from the energy storage device to pivot the thigh section forwardly about the hinged coupling thereof to the trunk socket. A dash-pot is coupled between the lower end of the thigh section and the foot section for damping flexion of the knee joint after a certain predetermined extent of ankle flexion is achieved to derive a more normal stride and cadence.