US3906340A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tuned circuit monitor for structural materials
Assignee: Individual
•
Filing: 1974-01-04
•
Granted: 1975-09-16
•
Expires: 1994-01-04
Abstract
Abstract The present invention is concerned with a system for sensing the integrity of structures using integral sensors consisting of small parallel tuned circuits whose electrical properties are monitored by means of oscillator means coupled to said tuned circuits.
Inventors
- 👤 Peter Mauri Wingfield
- 👤 Legal Representative Wingfield
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:14
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/22; G01N27/24
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
97 words
A system for sensing changes in the internal condition of solid materials using integral sensors embedded within the material wherein the sensors comprise resonant electric circuit means whose electrical characteristics are dependent on the condition of said material together with means for monitoring the electrical characteristics of said resonant electric circuit means, said circuit means comprising inductor means arranged electrically in parallel with capacitor means the dielectric of said capacitor means being formed by parts of said material, the electrical characteristics of said resonant electric circuit means being monitored by variable frequency oscillator means coupled inductively thereto.
Claim 2
Independent Claim
97 words
A system for sensing changes in the internal condition of solid materials using integral sensors embedded within the material wherein the sensors comprise resonant electric circuit means whose electrical characteristics are dependent on the condition of said material together with means for monitoring the electrical characteristics of said resonant electric circuit means, said circuit means comprising inductor means arranged electrically in parallel with capacitor means the dielectric of said capacitor means being formed by parts of said material, the electrical characteristics of said resonant electric circuit means being monitored by variable frequency oscillator means coupled inductively thereto.
Claim 3
Dependent Claim
39 words
A system according to claim 1 wherein said resonant electric circuit means includes conductor means embedded within the material the resistance of said conductor means varying according to the strain therein which corresponds to the strain in said material.
Claim 4
Independent Claim
101 words
A system for sensing changes in the internal condition of solid materials using integral sensors embedded within the material wherein the sensors comprise resonant electric circuit means whose electrical characteristics are dependent on the condition of said material together with means for monitoring the electrical characteristics of said resonant electric circuit means, said resonant electric circuit means comprising inductor means arranged electrically in parallel with capacitor means said inductor means being formed of strain gauge material whose resistance varies with extension thereof, the electrical characteristics of said resonant electric circuit means being monitored by variable frequency oscillator means coupled inductively thereto.
Claim 5
Independent Claim
101 words
A system for sensing changes in the internal condition of solid materials using integral sensors embedded within the material wherein the sensors comprise resonant electric circuit means whose electrical characteristics are dependent on the condition of said material together with means for monitoring the electrical characteristics of said resonant electric circuit means, said resonant electric circuit means comprising inductor means arranged electrically in parallel with capacitor means said inductor means being formed of strain gauge material whose resistance varies with extension thereof, the electrical characteristics of said resonant electric circuit means being monitored by variable frequency oscillator means coupled inductively thereto.
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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) | 1978-09-15 | 1979-03-17 | 1979-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-15 | 1983-03-17 | 1983-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-15 | 1987-03-17 | 1987-09-16 | $7700.00 | Window Closed / Lapsed |