PROSTHETIC WALKING FOOT

• US 20090204231A1
• Filed: 02/03/2009
• Published: 08/13/2009
• Est. Priority Date: 02/13/2008
• Status: Active Grant

• Current Assignee: Roadrunnerfoot engineering srl
• Original Assignee: Roadrunnerfoot engineering srl
• Inventors: Bonacini, Daniele
• Granted Patent: US 8,221,506 B2
• Time in Patent Office: Days
• US Class Current: 623/55
• CPC Class Codes: A61F 2/66 Feet; Ankle joints
• CPC Class Codes: A61F 2/76 Means for assembling, fitting or testing prostheses, e.g. for measuring or balancing, e.g. alignment means
• CPC Class Codes: A61F 2002/5079 Leaf springs A61F2002/6657 takes precedence
• CPC Class Codes: A61F 2002/665 Soles
• CPC Class Codes: A61F 2002/6678 L-shaped

Abstract

The prosthetic foot (1) consists of three or four laminas, a lower lamina (1a) defining the under-heel and the foot front, a rear lamina (1b) defining the heel and functioning as the Achilles tendon and as the soleus muscle, two upper laminas (1c and 1d) defining the front part of the foot and performing the function of the front tibial muscle, and a connector (2) in proximity to the ankle to serve as a coupling for a tube (3). The aim of this prosthetic foot is to simulate the behaviour of the human foot, in such a manner as to ensure good rear flexure and effective plantar flexure. The use of three or four laminas enables continuous energy absorption/return by the foot such as to allow assisted walking by the prosthetic foot at every moment. The prosthetic foot always operates via at least two laminas, of which one absorbs and the other returns energy. The device is arranged to be housed within an aesthetic covering.

Claims

1. A prosthetic walking foot comprising a connector fixable to a tube of an artificial limb, from said connector there extending at least one curved upper lamina which has its concavity facing frontwards, and is fixed to a lower lamina which is to be rested on the ground, characterised in that said lower lamina presents an initial portion defining an under-heel, an intermediate humped portion, and a final portion defining the foot front, said at least one upper lamina and said lower lamina being joined together in a region of said lower lamina interposed between said initial portion and said final portion, said foot also comprising a rear lamina which extends from said connector and presents a curved region with its concavity facing frontwards and having a final portion positioned below said hump between said initial portion and said final portion of said lower lamina.

2. A prosthetic foot as claimed in claim 1, characterised in that said lower lamina presents an aperture or slot through which said rear lamina passes.

3. A prosthetic foot as claimed in claim 1, characterised in that said aperture is provided in said intermediate humped portion of said lower lamina.

4. A prosthetic foot as claimed in claim 1, characterised in that said rear lamina presents an aperture through which said lower lamina passes.

5. A prosthetic foot as claimed in claim 1, characterised by presenting two upper laminas.

6. A prosthetic foot as claimed in claim 1, characterised in that said at least one upper lamina presents a straight first portion fixed to said connector, a curved intermediate portion, and a straight terminal portion, the curved intermediate portion having its centre of curvature (C_lsup) positioned at ⅔

the length of the foot and at a height corresponding to the commencement of its straight portion.

7. A prosthetic foot as claimed in claim 1, characterised in that said initial portion and said final portion of said lower lamina are curved with their concavity facing upwards, said lower lamina also presenting a straight portion interposed between said humped portion and said curved final portion, the connection between said lower lamina and said at least one upper lamina being made at said straight portion of said lower lamina.

8. A prosthetic foot as claimed in claim 1, characterised in that said humped portion of said lower lamina has its vertex located on an axis of said connector along which the user'"'"'s weight is discharged.

9. A prosthetic foot as claimed in claim 1, characterised in that said final curved portion of said lower lamina can optionally present an inflection.

10. A prosthetic foot as claimed in claim 1, characterised in that said rear lamina presents in series:

a straight first portion fixed to said connector, a intermediate curved portion with centre of curvature C_lpost, a straight portion and a final curved portion with concavity facing upwards and terminating at about the centre of the prosthetic foot, the straight portion of said rear lamina straddling said lower lamina.

11. A prosthetic foot as claimed in claim 1, characterised by presenting a pad of elastomeric material interposed between the upper face of the final portion of the rear lamina and the lower face of the lower lamina.

12. A prosthetic foot as claimed in claim 1, characterised in that second pads are positioned below the initial portion and final portion of the lower lamina and below the final portion of the rear lamina.

13. A prosthetic foot as claimed in claim 1, characterised in that said connector is fixed to the front of said rear lamina and of said at least one upper lamina.

14. A prosthetic foot as claimed in claim 1, characterised in that an axis of said connector, coinciding with a force application axis when said prosthetic foot is worn, passes in proximity to a vertex (V_linf) of said humped portion of said lower lamina.