Frictionless vertical suspension mechanism for prosthetic feet

Patent metadata

Field	Value
Publication number	US-9028559-B2
Application number	US-201213626567-A
Country	US
Kind code	B2
Filing date	Sep 25, 2012
Priority date	Sep 26, 2011
Publication date	May 12, 2015
Grant date	May 12, 2015

Abstract

A vertical suspension system for a prosthetic foot includes a first member operatively coupleable to an amputee's residual leg. The suspension system can also include a second member coupleable to a prosthetic foot. One or more upper leaf springs and one or more lower leaf springs extend between and are attached to the first and second members such that at least one of the ends of each leaf spring is rotationally fixed to the first or second members, where the upper an lower leaf springs are spaced apart from each other.

First claim

What is claimed is:

1. A vertical suspension system for a prosthetic foot, comprising:
a first member having an upper coupling location and a lower coupling location wherein the first member is adapted to be operatively coupled to an amputee's residual leg;
a second member having an upper coupling location and a lower coupling location wherein the second member is horizontally spaced from and positioned rearward of the first member and adapted to be coupled to the prosthetic foot;
at least one upper leaf spring having a first end portion and a second end portion that are located on opposite ends of the upper leaf spring, wherein the first end portion of the upper leaf spring is coupled to the first member's upper coupling location and the second end portion of the upper leaf spring is coupled to the second member's upper coupling location such that the upper leaf spring extends between the first member and the second member, and at least one of the upper leaf spring's first end portion and second end portion being rotationally fixed to at least one of the first member and the second member; and
at least one lower leaf spring having a first end portion and a second end portion that are located on opposite ends of the lower leaf spring, wherein the first end portion of the lower leaf spring is coupled to the first member's lower coupling location and the second end portion of the lower leaf spring is coupled to the second member's lower coupling location such that the lower leaf spring extends between the first member and the second member, and at least one of the lower leaf spring's first end portion and second end portion being rotationally fixed to at least one of the first member and the second member.

2. The vertical suspension system of claim 1 , wherein when the prosthetic foot is loaded, the first member and first end portions of the upper and lower leaf springs move vertically downwardly and the upper and lower leaf springs flex or pivot so that an angle of the leaf springs relative to a plane parallel to a ground surface varies between about plus and minus 45 degrees in use.

3. The vertical suspension system of claim 2 , wherein the angle of the leaf springs relative to the plane parallel to the ground surface varies between about plus and minus 30 degrees in use.

4. The vertical suspension system of claim 2 , wherein the angle of the leaf springs relative to the plane parallel to the ground surface varies between about plus and minus 15 degrees in use.

5. The vertical suspension system of claim 1 , wherein a capturing mechanism couples to a repositionable leaf spring extending between the first member and the second member.

6. The vertical suspension system of claim 1 , wherein the upper leaf spring is within plus or minus 10 degrees of being parallel to the lower leaf spring.

7. The vertical suspension system of claim 1 , wherein the upper leaf spring and the lower leaf spring are substantially flat in an unloaded state.

8. The vertical suspension system of claim 1 , wherein the upper leaf spring and the lower leaf spring are oriented within plus or minus 30 degrees relative to a horizontal surface on which the prosthetic foot stands in an unloaded state.

9. The vertical suspension system of claim 1 , wherein the first end portion of the upper leaf spring is rotationally fixed to the first member, the second end portion of the upper leaf spring is rotationally fixed to the second member, the first end portion of the lower leaf spring is rotationally fixed to the first member, and the second end portion of the lower leaf spring is rotationally fixed to the second member.

10. The vertical suspension system of claim 1 , wherein the at least one upper leaf spring comprises a plurality of upper planar leaf springs that are spaced apart from each other and extend generally horizontally between the first member and the second member when the vertical suspension system is in an unloaded state and wherein the at least one lower leaf spring comprises a plurality of lower planar leaf springs that are spaced apart from each other and extend generally horizontally between the first member and the second member when the vertical suspension system is in an unloaded state.

11. The vertical suspension system of claim 1 , wherein the first end portions of the at least one upper and lower leaf springs move between about 5 mm and about 20 mm relative to the second end portions of the leaf springs under applied loads of between about 500 N to about 3,000 N.

12. A prosthetic foot, comprising:
a foot plate extending from a generally vertical proximal portion to a generally horizontal distal portion, the foot plate curving downwardly and forwardly between the proximal and distal portions;
an adapter operably coupleable to the proximal portion of the prosthetic foot and disposed forwardly of said proximal portion, the adapter operably coupleable to a prosthetic socket; and
a plurality of parallel leaf springs that operably interconnect the adapter and the proximal portion of the prosthetic foot, the leaf springs spaced apart from each other and extending generally horizontally between the adapter and the proximal portion of the prosthetic foot when the prosthetic foot is at rest.

13. The prosthetic foot of claim 12 , further comprising a connector removably coupleable to the proximal portion of the prosthetic foot, the plurality of parallel leaf springs interconnecting the connector and the adapter.

14. The prosthetic foot of claim 12 , wherein the plurality of parallel leaf springs comprises a first set of parallel leaf springs and a second set of parallel leaf springs, where the first set of leaf springs is spaced apart from the second set of leaf springs by an amount larger than a spacing between individual leaf springs in the first and second sets of leaf springs.

15. The prosthetic foot of claim 14 , wherein the first set of parallel leaf springs is generally inclined relative to the second set of parallel leaf springs when the prosthetic foot is at rest.

16. A vertical suspension system, comprising:
a first member having an upper coupling location and a lower coupling location;
a second member having an upper coupling location and a lower coupling location wherein the second member is horizontally spaced from and disposed across from the first member and configured to be fixedly coupled to a support component, the first member being movable relative to the second member;
at least one upper leaf spring having a first end portion and a second end portion that are located on opposite ends of the upper leaf spring, wherein the first end portion of the upper leaf spring is coupled to the first member's upper coupling location and the second end portion of the upper leaf spring is coupled to the second member's upper coupling location, and at least one of the upper leaf spring's first end portion and second end portion being rotationally fixed to at least one of the first member and the second member; and
at least one lower leaf spring having a first end portion and a second end portion that are located on opposite ends of the lower leaf spring, wherein the first end portion of the lower leaf spring is coupled to the first member's lower coupling location and the second end portion of the lower leaf spring is coupled to the second member's lower coupling location, and at least one of the lower leaf spring's first end portion and second end portion being rotationally fixed to at least one of the first member and the second member.

17. The vertical suspension system of claim 16 , wherein the at leas

Assignees

• Ossur Hf
• Ssur Hf

Inventors

• Lecomte Christophe
• Skulason Benedikt
• Nijman Jeroen

Classifications

• A61F2002/5003

  having damping means, e.g. shock absorbers · CPC title

• A61F2002/6657

  having a plate-like or strip-like spring element, e.g. an energy-storing cantilever spring keel · CPC title

• A61F2/66 Primary

  Feet; Ankle joints · CPC title

• A61F2002/5079

  Leaf springs (A61F2002/6657 takes precedence) · CPC title

• A61F2002/607

  Lower legs · CPC title