US3920610A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making and tailoring prosthetic feet
Assignee: Individual
•
Filing: 1974-04-24
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Granted: 1975-11-18
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Expires: 1994-04-24
Abstract
Abstract A method of making prosthetic or artificial feet comprising forming a wooden keel for the ankle portion which has a diminished heel portion, a flat arch portion, a curved instep portion, a rounded lower front end portion and a flat top; securing a reinforcing member comprising a highly resilient synthetic resin (preferably nylon) strip at its rear end to said flat arch portion with its front end extending forwardly into a toe portion to be molded around it to give the toe predetermined flexibility; and molding a one piece soft resilient foot-forming foam coating under and around said keel and reinforcing member. The exposed broad surfaces of said strip may be coated to bond it to said foam coating. The method of making such artificial feet may provide heel portions of predetermined variable density and toe portions of predetermined flexibility to tailor a foot to the characteristics of an amputee by fashioning the keel with its heel portion properly diminished for the predetermined heel density, preparing the reinforcing strip to provide the predetermined toe flexibility by choice of composition, gauge, length and number of highly resilient synthetic resin (preferably at least one nylon) strips, securing it properly to the keel and molding the soft synthetic resin foam under and around said keel and reinforcing member.
Inventors
- 👤 Eugene Wagner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:30
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/50; A61F2/60; A61F2/66; B; B29; B29C; B29C44/00; B29C44/02; B29C44/12; B29C44/1271; A61F2002/6614; A61F2002/6657
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
93 words
THE METHOD OF MAKING A PROSTHETIC FOOT CONPRISING FORMING A KEEL HAVING DIMINISHED HEEL PORTION, A SUBSTANTIALLY FLAT ARCH PORTION, A CURVED INSTEP PORTION AND A ROUNDED LOWER FRONT END PORTION, FASTENING TO SAID FLAT ARCH PORTION THE REAR END OF A REINFORCING MEMBER COMPRISING A STRIP OF HIGHLY RESILIENT SYNTHETIC RESIN THE FRONT END OF WHICH EXTENDS ALMOST TO THE END OF THE TOE TO BE FORMED AROUND IT, AND MOLDING A SOFT RESILIENT FOAM COATING COMPROSISING TOE PORTION, INSTEP, ANKLE, HEAL AND ARCH UNDER AND AROUND SAID KEEL AND REINFORCING MEMBER.
Claim 2
Independent Claim
93 words
THE METHOD OF MAKING A PROSTHETIC FOOT CONPRISING FORMING A KEEL HAVING DIMINISHED HEEL PORTION, A SUBSTANTIALLY FLAT ARCH PORTION, A CURVED INSTEP PORTION AND A ROUNDED LOWER FRONT END PORTION, FASTENING TO SAID FLAT ARCH PORTION THE REAR END OF A REINFORCING MEMBER COMPRISING A STRIP OF HIGHLY RESILIENT SYNTHETIC RESIN THE FRONT END OF WHICH EXTENDS ALMOST TO THE END OF THE TOE TO BE FORMED AROUND IT, AND MOLDING A SOFT RESILIENT FOAM COATING COMPROSISING TOE PORTION, INSTEP, ANKLE, HEAL AND ARCH UNDER AND AROUND SAID KEEL AND REINFORCING MEMBER.
Claim 3
Dependent Claim
43 words
The method of making a prosthetic foot as set forth in claim 1 in which said reinforcing member is coated prior to the molding operation with an adherent material that bonds in the molding operation to the foam coating material in contact therewith.
Claim 4
Dependent Claim
50 words
The method of making a prosthetic foot as set forth in claim 1 in which the flexibility of said toe portion as determined by the herein described toe flexibility test is controlled by the gauge and structure of the reinforcing member within the limits of 15 mm. to 50 mm.
Claim 5
Dependent Claim
26 words
The method of making a prosthetic foot as set forth in claim 1 in which said reinforcing member comprises a strip of nylon of predetermined flexibility.
Claim 6
Dependent Claim
36 words
The method of making a prosthetic foot as set forth in claim 4 in which said reinforcing member includes a shorter upper supplemental strip secured to said flat arch portion and to the longer nylon strip.
Claim 7
Dependent Claim
25 words
The method of making a prosthetic foot as set forth in claim 4 in which said strip of nylon is cut from coated oriented belting.
Claim 8
Dependent Claim
40 words
The method of making a prosthetic foot as set forth in claim 6 in which the reinforcing member includes a shorter upper supplemental strip of coated oriented belting secured to the flat arch portion and to the longer nylon strip.
Claim 9
Independent Claim
120 words
The method of tailoring a prosthetic foot to the characteristics of an amputee comprising determining the toe flexibility and heel density required properly to conform to said characteristics, fashioning a keel with a substantially flat arch and a diminished heel to conform to said required heel density, preparing a reinforcing member of suitable length having at least one nylon strip to provide said required toe flexibility, securing the rear end of said member to the flat arch of said keel, and molding a soft resilient foam covering of polyurethane resin under and around said keel and member to form a foot comprising a toe portion of predetermined flexibility, an instep, an ankle, a heel of predetermined density and an arch.
Claim 10
Independent Claim
120 words
The method of tailoring a prosthetic foot to the characteristics of an amputee comprising determining the toe flexibility and heel density required properly to conform to said characteristics, fashioning a keel with a substantially flat arch and a diminished heel to conform to said required heel density, preparing a reinforcing member of suitable length having at least one nylon strip to provide said required toe flexibility, securing the rear end of said member to the flat arch of said keel, and molding a soft resilient foam covering of polyurethane resin under and around said keel and member to form a foot comprising a toe portion of predetermined flexibility, an instep, an ankle, a heel of predetermined density and an arch.
Claim 11
Dependent Claim
38 words
The method as set forth in claim 8 in which said nylon strip is coated prior to the molding operation with an adherent material that bonds in the molding operation to the foam covering material in contact therewith.
Claim 12
Dependent Claim
128 words
The method as set forth in claim 8 in which the molding of said polyurethane is carried out by fashioning said keel with a flat top portion; firmly mounting said keel upside down in a mold comprising a flat bottom, an open top and upwardly extending walls conforming to the finished shape of the visible portions of the foot when it rests on the sole; preparing a formable polyurethane resin composition to form the soft resilient foam covering; introducing the prepared composition through said open top into the space around said keel and reinforcing strip; placing a cover over said open top to close the mold and resist the pressure generated; maintaining the mold closed until the foaming reaction is completed; and removing the foot from the mold.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-17 | 1979-05-19 | 1979-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-17 | 1983-05-19 | 1983-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-17 | 1987-05-19 | 1987-11-18 | $7700.00 | Window Closed / Lapsed |