US3966326A
Expired / Lapsed
US
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Method and apparatus for indicating or measuring contact distribution over a surface
Assignee: Ramot at Tel Aviv University Ltd
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Filing: 1975-03-17
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Granted: 1976-06-29
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Expires: 1995-03-17
Abstract
Abstract A method and apparatus are described for indicating or measuring contact pressure distribution over a surface, in which method and apparatus, a pressure-transmitting member having a plurality of point-contact projections is used to transmit the contact pressure, in the form of a plurality of localized points, to a photoelastic member. The photoelastic member is one whose optical properties are changed when the member is subjected to pressure, and the changes in optical properties are optically displayed by directing polarized light onto the photoelastic member to produce interference patterns at the localized points of contact pressure.
Inventors
- 👤 Maurice A. Brull
- 👤 Mircea Arcan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:15
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/117; A61B5/1171; A61B5/1174; G; G01; G01G; G01G19/00; G01G19/44; G01L; G01L1/00; G01L1/24; G01L1/241
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
84 words
A method for indicating the contact pressure distribution over a surface, comprising the steps: transmitting the contact pressure to be indicated to a photoelastic member through a pressure-transmitting member having a plurality of point-contact projections effective to transmit said contact pressure to the photoelastic member in the form of a plurality of localized points, the photoelastic member being one whose optical properties are changed when the member is subjected to pressure; and optically displaying the changes in the optical properties of the photoelastic member.
Claim 2
Independent Claim
84 words
A method for indicating the contact pressure distribution over a surface, comprising the steps: transmitting the contact pressure to be indicated to a photoelastic member through a pressure-transmitting member having a plurality of point-contact projections effective to transmit said contact pressure to the photoelastic member in the form of a plurality of localized points, the photoelastic member being one whose optical properties are changed when the member is subjected to pressure; and optically displaying the changes in the optical properties of the photoelastic member.
Claim 3
Dependent Claim
39 words
The method as defined in claim 1, wherein the changes in the optical properties of the photoelastic member are displayed by directing polarized light onto the photoelastic member to produce interference patterns at the localized points of contact pressure.
Claim 4
Dependent Claim
82 words
Apparatus for indicating the contact pressure distribution over a surface, comprising: a photoelastic member whose optical properties are changed when the member is subjected to pressure; a pressure-transmitting member having one surface adapted to receive the contact pressure, the opposite surface including a plurality of point-contact projections effective to transmit the contact pressure in the form of a plurality of localized pressure points to the photoelastic member; and means for optically displaying the changes in the optical properties of the photoelastic member.
Claim 5
Dependent Claim
82 words
Apparatus for indicating the contact pressure distribution over a surface, comprising: a photoelastic member whose optical properties are changed when the member is subjected to pressure; a pressure-transmitting member having one surface adapted to receive the contact pressure, the opposite surface including a plurality of point-contact projections effective to transmit the contact pressure in the form of a plurality of localized pressure points to the photoelastic member; and means for optically displaying the changes in the optical properties of the photoelastic member.
Claim 6
Dependent Claim
34 words
Apparatus as defined in claim 3, wherein said optically-displaying means comprises a light-source directing light to the photoelastic member, and a circular polarizer polarizing the light from the source received by the photoelastic member.
Claim 7
Dependent Claim
35 words
Apparatus as defined in claim 4, further including a light reflector on the side of the photoelastic member facing the projections, the opposite side of the photoelastic member facing the light source and the polarizer.
Claim 8
Dependent Claim
30 words
Apparatus as defined in claim 5, wherein the light reflector is in the form of a thin sheet or coating on the face of the photoelastic member facing said projections.
Claim 9
Dependent Claim
37 words
Apparatus as defined in claim 5, wherein said photoelastic member and light polarizer are supported on one face of a rigid transparent plate, the light source being disposed on the opposite side of the rigid transparent plate.
Claim 10
Dependent Claim
35 words
Apparatus as defined in claim 7, further including a transparent elastic sheet between the polarizer and the rigid transparent plate, said transparent elastic sheet forming a sandwich with the photoelastic member with the polarizer inbetween.
Claim 11
Dependent Claim
20 words
Apparatus as defined in claim 8, wherein said transparent elastic sheet is of the same material as the photoelastic member.
Claim 12
Dependent Claim
27 words
Apparatus as defined in claim 7, further including a camera for photographing the light reflected from said reflector through the photoelastic member, polarizer and transparent supporting plate.
Claim 13
Dependent Claim
24 words
Apparatus as defined in claim 3, wherein said point-contact projections carried by the pressure-transmitting member have rounded tips in contact with the photoelastic member.
Claim 14
Dependent Claim
15 words
Apparatus as defined in claim 3, wherein the pressure-transmitting member is a thin, flexible sheet.
Claim 15
Dependent Claim
35 words
Apparatus as defined in claim 3, wherein said pressure-transmitting member is in the shape of the sole of a shoe for measuring the pressure distribution of a person's weight over the soles of his feet.
Claim 16
Dependent Claim
24 words
Apparatus as defined in claim 13, wherein said sole-shaped pressure-transmitting member is built into and constitutes a part of the sole of the shoe.
Claim 17
Dependent Claim
19 words
Apparatus as defined in claim 3, wherein said photoelastic member, polarizer, and pressure-transmitting member are formed as one unit.
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) | 1979-06-29 | 1979-12-29 | 1980-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-29 | 1983-12-29 | 1984-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-29 | 1987-12-29 | 1988-06-29 | $7700.00 | Window Closed / Lapsed |