US3754286A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Artificial foot having ankle flexible mount
Assignee: Individual
•
Filing: 1972-01-21
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Granted: 1973-08-28
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Expires: 1992-01-21
Abstract
Abstract An artificial foot including an improved ankle and foot mount is attached to a conventional stump mounted artificial leg. A coil spring extends downwardly from rigid attachment to the artificial limb in the vicinity of the ankle at the upper end and attaches rigidly to a plate in the plane of the sole of the foot at the lower end. The sole plate, extending from the heel to the ball of the foot, cantilevers from the coil spring to emulate natural foot action during walking. A second sole plate support, capable of accommodating both tension and compression as well as side to side foot motion, extends from a mount on the sole plate at the ball of the artificial foot upwardly at an angle to a mount on the ankle of the artificial limb. This provides improved toe action of the artificial limb. Provision is made for mounting either a spring or a variable resistance shock absorber to act in combination with the second spring to imulate natural foot motion.
Inventors
- 👤 M Ryan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:36
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/50; A61F2/60; A61F2/66; A61F2/6607; A61F2002/5072; A61F2002/5073; A61F2002/5075
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
186 words
An artificial foot adapted to simulate the flexing motion of a normal foot, said artificial foot comprising: a rigid horizontal ankle plate having an exposed upper attachment surface, said ankle plate having a forward portion and a rearward portion; a rigid horizontal sole plate disposed below the ankle plate and substantially parallel therewith, said sole plate having a heel-defining portion substantially beneath the rearward portion of the ankle plate and a ball-defining portion extending beyond the forward portion of the ankle plate; a substantially vertical coil spring disposed intermediate the ankle plate and the sole plate, said coil spring having an upper end rigidly attached to the lower surface of the ankle plate and a lower end rigidly attached to the upper surface of the sole plate; and a bar extending from the forward portion of the ankle plate to the ball-defining portion of the sole plate, said bar universally pivotably connected to said ankle plate at one end of said bar and to said sole plate at the other end of said bar to allow relative rotation theRebetween while maintaining a fixed radial distance therebetween.
Claim 2
Dependent Claim
186 words
An artificial foot adapted to simulate the flexing motion of a normal foot, said artificial foot comprising: a rigid horizontal ankle plate having an exposed upper attachment surface, said ankle plate having a forward portion and a rearward portion; a rigid horizontal sole plate disposed below the ankle plate and substantially parallel therewith, said sole plate having a heel-defining portion substantially beneath the rearward portion of the ankle plate and a ball-defining portion extending beyond the forward portion of the ankle plate; a substantially vertical coil spring disposed intermediate the ankle plate and the sole plate, said coil spring having an upper end rigidly attached to the lower surface of the ankle plate and a lower end rigidly attached to the upper surface of the sole plate; and a bar extending from the forward portion of the ankle plate to the ball-defining portion of the sole plate, said bar universally pivotably connected to said ankle plate at one end of said bar and to said sole plate at the other end of said bar to allow relative rotation theRebetween while maintaining a fixed radial distance therebetween.
Claim 3
Dependent Claim
44 words
The invention of claim 1 and additionally comprising ball sockets on the forward portion of the ankle plate and the ball-defining portion of the sole plate, and wherein the bar has balls mounted at either end thereof, said balls captured in said ball sockets.
Claim 4
Dependent Claim
95 words
The invention of claim 2 and wherein the forward portion of the ankle plate has a depending inclined planar surface substantially normal to the longitudinal axis of the bar, and wherein the ball socket on the forward portion of the ankle plate is mounted on said depending planar surface, and wherein the ball-defining portion of the sole plate has an upwardly projecting inclined planar surface substantially normal to the longitudinal axis of the bar, and wherein the ball socket on the ball-defining portion of the sole plate is mounted on said upwardly projecting planar surface.
Claim 5
Dependent Claim
22 words
The invention of claim 1 and wherein the sole plate has cutout portions therein to reduce the weight of said sole plate.
Claim 6
Dependent Claim
36 words
The invention of claim 1 and wherein said ankle plate has an aperture therethrough, and additionally cmprising a threaded bolt projecting upwardly through the aperture in said ankle plate to facilitate attachment to an artificial leg.
Claim 7
Dependent Claim
30 words
The invention of claim 1 wherein said coil spring extending between said ankle plate and sole plate has a diameter substantially the same as the width of said ankle plate.
Claim 8
Dependent Claim
38 words
The invention of claim 1 and wherein said ankle plate, sole plate, coil spring and support are encased within a rubber molding; and said rubber molding is conformed in its exterior profile to the shape of a foot.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |