Energy returning prosthetic joint

Abstract

An energy returning prosthetic joint arranged for use as a knee joint in prosthetic limbs includes a biasing or spring member connected to upper and lower attachment members. The spring member includes a composite material having an energy returning property. A cushion may be provided within the range of curvature of the spring member, or be connected to frame members in order to limit motion of the spring member.

1 . An energy returning prosthetic joint, comprising:
 a spring member formed of a material having an energy returning property, the spring member defining at least one asymmetrical curvilinear portion defining an open space, the spring having top and bottom sections extending from opposed ends of the at least one curvilinear portion.   
   
   
       2 . The prosthetic joint according to  claim 1 , wherein the bottom section generally extends linearly, the top section oriented obliquely relative to the bottom section. 
   
   
       3 . The prosthetic joint according to  claim 2 , further comprising first and second attachment members connected to the top and bottom sections of the spring member, the first and second attachment members oriented generally along the same axis. 
   
   
       4 . The prosthetic joint according to  claim 1 , further comprising a limiting member coupled to said spring member within said open space. 
   
   
       5 . The prosthetic joint according to  claim 1 , wherein:
 the at least one curvilinear portion includes an upper asymmetric curvilinear portion, and a lower asymmetric curvilinear portion, the upper and lower curvilinear portions each defining a convex open space, the upper and lower curvilinear portions being connected to one another at corresponding ends thereof, and oriented in opposite directions relative to one another.   
   
   
       6 . An energy returning prosthetic joint, comprising:
 a lower frame member having a lower portion and an upper portion;   an upper mount member pivotally connected to the upper portion of the lower frame member; and   a biasing member having an upper end and a lower end, the lower end of the biasing member connected to the lower portion of the lower frame member and the upper end of the biasing member connected to the upper mount member; and   a damper disposed between the upper mount and the lower frame members such that the biasing member urges the upper mount and lower frame member towards one another with the damper therebetween in a stance phase.   
   
   
       7 . An energy returning prosthetic joint, comprising:
 a lower frame member having a lower portion and an upper portion;   an upper mount member pivotally connected to the upper portion of the lower frame member; and   a biasing member having an upper end and a lower end, the lower end of the biasing member connected to the lower portion of the lower frame member and the upper end of the biasing member connected to the upper mount member;   wherein during a stance phase, the biasing member is arranged to provide stance flexion and, during a swing phase, the biasing member is arranged to provide energy return;   wherein the lower frame member further comprises a cushion located near the upper portion of the lower frame member and also located anterior to the pivotal connection between the upper mount and the lower frame member, such that, when the prosthetic joint is in a stance phase, the upper mount is arranged to rest upon the cushion.