Patent US3200014A successfully refreshed from Google Patents.
Patent US5240643A successfully refreshed from Google Patents.
US5240643A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Strain sensing composites
Assignee: United States Department of the Navy
•
Filing: 1992-03-11
•
Granted: 1993-08-31
•
Expires: 2012-03-11
Abstract
Abstract This invention comprises the use of diacetylene-containing polymers, e.g.,olyamides containing reactive diacetylene groups that change their absorption in the visible spectrum with the application of strain as a strain sensing device in various organic matrix composites such as an epoxy laminated composite. The built in sensors in accordance with this invention will not affect the mechanical performance of the composite and will indicate strain without the need for extensive electronic equipment to measure the light pulse amplitude or phase before and after strain.
Inventors
- 👤 Leonard J. Buckley
- 👤 Gary C. Neumeister
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:57
CPC Classifications
G; G01; G01M; G01M11/00; G01M11/08; G01M11/083; G01L; G01L1/00; G01L1/24; G01L1/242; G02; G02B; G02B6/00; G02B6/02; G02B6/02033
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
47 words
A strain-sensing device comprising an effective amount of a strain-sensing polymer coated or cladded on a fiber optic embedded in an organic matrix composite to detect strain; said strain-sensing polymer consisting essentially of a diacetylene-containing polymer capable of changing absorption in the visible spectrum while under strain.
Claim 2
Dependent Claim
47 words
A strain-sensing device comprising an effective amount of a strain-sensing polymer coated or cladded on a fiber optic embedded in an organic matrix composite to detect strain; said strain-sensing polymer consisting essentially of a diacetylene-containing polymer capable of changing absorption in the visible spectrum while under strain.
Claim 3
Dependent Claim
15 words
The strain-sensing composite of claim 1 wherein the diacetylene-containing polymer is a copolymer of diacetylene.
Claim 4
Dependent Claim
14 words
The strain-sensing composite of claim 1 wherein the diacetylene-containing polymer is a diacetylene-containing polyamide.
Claim 5
Dependent Claim
23 words
The strain-sensing composite of claim 1 wherein the strain-sensing polymer is a polyamide-diacetylene polymer cladded on optical fibers embedded in an epoxy matrix.
Claim 6
Independent Claim
43 words
A method of detecting strain in an organic matrix composite which comprises incorporating in said composite a strain detecting amount of a strain-sensing polymer; said strain-sensing polymer consisting essentially of diacetylene-containing polymers capable of changing absorption in the visible spectrum while under strain.
Claim 7
Independent Claim
43 words
A method of detecting strain in an organic matrix composite which comprises incorporating in said composite a strain detecting amount of a strain-sensing polymer; said strain-sensing polymer consisting essentially of diacetylene-containing polymers capable of changing absorption in the visible spectrum while under strain.
Claim 8
Dependent Claim
14 words
The method of claim 5 wherein the diacetylene-containing polymer is cladded on optical fibers.
Claim 9
Dependent Claim
14 words
The method of claim 5 wherein the diacetylene-containing polymer is a copolymer of diacetylene.
Claim 10
Dependent Claim
12 words
The method of claim 5 wherein the diacetylene-containing polymer is a polyamide-diacetylene.
Claim 11
Dependent Claim
19 words
The method of claim 5 wherein the strain on the organic matrix composite is detected with a strain gauge.
References Cited (Backward Citations)
US4515429A
Cited
US4875759A
Cited
US5018829A
Cited
US4849500A
Cited
US4916211A
Cited
US5085801A
Cited
US4788151A
Cited
US4789637A
Cited
US5094527A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-08-30 | 1997-03-01 | 1997-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-08-30 | 2001-03-01 | 2001-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-08-30 | 2005-03-01 | 2005-08-31 | $7700.00 | Window Closed / Lapsed |