US5408873A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Foot force sensor
Assignee: Cleveland Medical Devices Inc
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Filing: 1994-07-25
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Granted: 1995-04-25
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Expires: 2014-07-25
Abstract
Abstract Foot force sensor for measuring compressive force exerted by a foot. The foot force sensor is in the form of an insole made of layers of relatively thin, planar, flexible, resilient, dielectric material. Electrical contact means having first and second poles and electrical leads extending therefrom is interposed between the layers of the insole. An electrically resistive material is also interposed between the layers of the insole but displaced from the electrical contact means. An electrically conductive interconnecting means is connected between the electrical contact means and the electrically resistive material. The electrically conductive interconnecting means has a plurality of electrically isolated conductive paths laterally displaced from one another and extending through it. The electrically conductive interconnecting means has an electrical resistance which decreases as a compressive force applied to it increases, whereby a closed electrical circuit with shear and hysteresis effects reduced by at least about 20% and with resistance varying with the amount of compressive force applied to the insole is established between the first pole and the second pole of the electrical contact means through the electrically conductive interconnecting means and the electrically resistive material.
Inventors
- 👤 Robert N. Schmidt
- 👤 Howard J. Chizeck
- 👤 Richard S. Diefes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:22
CPC Classifications
G; G01; G01L; G01L1/00; G01L1/20; A; A43; A43B; A43B3/00; A43B3/34; A61; A61B; A61B5/00; A61B5/103; A61B5/1036
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
202 words
A foot force sensor, comprising: (a) an insole having a plurality of layers of relatively thin, planar, flexible, resilient, dielectric material; and (b) electrical contact means attached to said insole said electrical contact means having first and second poles defining an open circuit configuration and electrical leads extending from said first and second poles; and (c) electrically resistive material applied to said insole such that said electrically resistive material is displaced from said electrical contact means; and (d) electrically conductive interconnecting means having first and second faces, said first face electrically connected to said electrical contact means and said second face electrically connected said electrically resistive material, said electrically conductive interconnecting means having a plurality of electrically isolated conductive paths laterally displaced from one another and extending from said first face to said second face, said electrically conductive interconnecting means having an electrical resistance which decreases as a compressive force applied to said first or second face increases whereby a closed electrical circuit with resistance varying with the amount of compressive force applied to said insole is established between said first pole and said second pole of said electrical contact means through said electrically conductive interconnecting means and said electrically resistive material.
Claim 2
Dependent Claim
202 words
A foot force sensor, comprising: (a) an insole having a plurality of layers of relatively thin, planar, flexible, resilient, dielectric material; and (b) electrical contact means attached to said insole said electrical contact means having first and second poles defining an open circuit configuration and electrical leads extending from said first and second poles; and (c) electrically resistive material applied to said insole such that said electrically resistive material is displaced from said electrical contact means; and (d) electrically conductive interconnecting means having first and second faces, said first face electrically connected to said electrical contact means and said second face electrically connected said electrically resistive material, said electrically conductive interconnecting means having a plurality of electrically isolated conductive paths laterally displaced from one another and extending from said first face to said second face, said electrically conductive interconnecting means having an electrical resistance which decreases as a compressive force applied to said first or second face increases whereby a closed electrical circuit with resistance varying with the amount of compressive force applied to said insole is established between said first pole and said second pole of said electrical contact means through said electrically conductive interconnecting means and said electrically resistive material.
Claim 3
Dependent Claim
25 words
The foot force sensor of claim 1 wherein said first and second poles of said electrical contact means are a plurality of interdigitating conductive fingers.
Claim 4
Dependent Claim
19 words
The foot force sensor of claim 1 wherein said electrical contact means is conductive ink applied to said insole.
Claim 5
Dependent Claim
15 words
The foot force sensor of claim 3 wherein said conductive ink is silver conductive ink.
Claim 6
Dependent Claim
25 words
The foot force sensor of claim 3 wherein said conductive ink has a resistivity of less than about 0.02 ohms per square per 25 micron.
Claim 7
Dependent Claim
21 words
The foot force sensor of claim 3 wherein said conductive ink has a width of not greater than about 0.02 inches.
Claim 8
Dependent Claim
19 words
The foot force sensor of claim 1 wherein said electrically resistive material is carbon ink applied to said insole.
Claim 9
Dependent Claim
15 words
The foot force sensor of claim 1 wherein said dielectric material is a polyester material.
Claim 10
Dependent Claim
43 words
The foot force sensor of claim 1 wherein said electrical contact means, said electrically resistive material and said electrically conductive interconnecting means are positioned on said insole to align with the heel, and 1st, 2nd, and 5th metatarsal heads of a human foot.
Claim 11
Dependent Claim
232 words
A foot force sensor, comprising: (a) an insole having first and second layers, said layers composed of relatively thin, flexible, planar, resilient dielectric material, said layers juxtaposed to one another in a face-to-face stacked relationship; and (b) an electrically resistive material interposed between said first and second layers; and (c) electrical contact means interposed between said first and second layers such that said electrical contact means is displaced from said electrically resistive material, said electrical contact means having first and second poles defining an open circuit configuration and electrical leads extending from said first and second poles; and (d) electrically conductive interconnecting means having first and second faces interposed between said first and second layers, said first face electrically connected to said electrical contact means and said second face electrically connected to said electrically resistive material, said electrically conductive interconnecting means having a plurality of electrically isolated conductive paths laterally displaced from one another and extending from said first face to said second face, said electrically conductive interconnecting means having an electrical resistance which decreases as a compressive force applied to said first or second face increases such that a closed electrical circuit with resistance varying with the amount of compressive force applied to said insole is established between said first pole and said second pole of said electrical contact means through said electrically conductive interconnecting means and said electrically resistive material.
Claim 12
Dependent Claim
232 words
A foot force sensor, comprising: (a) an insole having first and second layers, said layers composed of relatively thin, flexible, planar, resilient dielectric material, said layers juxtaposed to one another in a face-to-face stacked relationship; and (b) an electrically resistive material interposed between said first and second layers; and (c) electrical contact means interposed between said first and second layers such that said electrical contact means is displaced from said electrically resistive material, said electrical contact means having first and second poles defining an open circuit configuration and electrical leads extending from said first and second poles; and (d) electrically conductive interconnecting means having first and second faces interposed between said first and second layers, said first face electrically connected to said electrical contact means and said second face electrically connected to said electrically resistive material, said electrically conductive interconnecting means having a plurality of electrically isolated conductive paths laterally displaced from one another and extending from said first face to said second face, said electrically conductive interconnecting means having an electrical resistance which decreases as a compressive force applied to said first or second face increases such that a closed electrical circuit with resistance varying with the amount of compressive force applied to said insole is established between said first pole and said second pole of said electrical contact means through said electrically conductive interconnecting means and said electrically resistive material.
Claim 13
Dependent Claim
25 words
The foot force sensor of claim 10 wherein said first and second poles of said electrical contact means are a plurality of interdigitating conductive fingers.
Claim 14
Dependent Claim
19 words
The foot force sensor of claim 10 wherein said electrical contact .means is conductive ink applied to said insole.
Claim 15
Dependent Claim
15 words
The foot force sensor of claim 12 wherein said conductive ink is silver conductive ink.
Claim 16
Dependent Claim
25 words
The foot force sensor of claim 12 wherein said conductive ink has a resistivity of less than about 0.02 ohms per square per 25 microns.
Claim 17
Dependent Claim
21 words
The foot force sensor of claim 12 wherein said conductive ink has a width of not greater than about 0.02 inches.
Claim 18
Dependent Claim
19 words
The foot force sensor of claim 10 wherein said electrically resistive material is carbon ink applied to said insole.
Claim 19
Dependent Claim
13 words
The foot force sensor of claim 10 wherein said dielectric material is polyester.
Claim 20
Dependent Claim
42 words
The foot force sensor of claim 12 wherein said electrical contact means, electrically resistive material and said electrically conductive interconnecting means are positioned on said insole to align with the heel, and 1st, 2nd and 5th metatarsal heads of a human foot.
References Cited (Backward Citations)
US4426884A
Cited
US4503705A
Cited
WO1987001574A1
Cited
US4644101A
Cited
US4745930A
Cited
US5033291A
Cited
US5253654A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-04-24 | 1998-10-24 | 1999-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-04-24 | 2002-10-24 | 2003-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-04-24 | 2006-10-24 | 2007-04-25 | $7700.00 | Window Closed / Lapsed |