Patent US5562345A successfully refreshed from Google Patents.
US5562345A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for thermographically and quantitatively analyzing a structure for disbonds and/or inclusions
Assignee: National Aeronautics and Space Administration
•
Filing: 1995-12-13
•
Granted: 1996-10-08
•
Expires: 2015-12-13
Abstract
Abstract A heat source such as a magnetic induction/eddy current generator remotely heats a region of a surface of a test structure to a desired depth. For example, the frequency of the heating source can be varied to heat to the desired depth. A thermal sensor senses temperature changes in the heated region as a function of time. A computer compares these sensed temperature changes with calibration standards of a similar sample having known disbond and/or inclusion geography(ies) to analyze the test structure. A plurality of sensors can be arranged linearly to sense vector heat flow.
Inventors
- 👤 Joseph S. Heyman
- 👤 William P. Winfree
- 👤 K. Elliott Cramer
- 👤 Joseph N. Zalamedia
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:35
CPC Classifications
G; G01; G01N; G01N25/00; G01N25/72
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
123 words
A thermographic detection system for quantitatively analyzing a structure comprising: a remotely located magnetic induction heating source which generates eddy currents in the structure for heating a region of the structure; a plurality of thermal sensors arranged along a desired line for sensing temperature changes in the heated region of the structure over time along the desired line, said thermal sensors simultaneously sensing temperature at a single measurement instant; and a computer for assessing the sensed temperature changes quantitatively as a function of time wherein said computer compares the temperature changes sensed in the heated region of the structure with previously determined temperature changes of a calibration sample having known disbond and inclusion characteristics to indicate disbonds and inclusion characteristics of the structure.
Claim 2
Dependent Claim
123 words
A thermographic detection system for quantitatively analyzing a structure comprising: a remotely located magnetic induction heating source which generates eddy currents in the structure for heating a region of the structure; a plurality of thermal sensors arranged along a desired line for sensing temperature changes in the heated region of the structure over time along the desired line, said thermal sensors simultaneously sensing temperature at a single measurement instant; and a computer for assessing the sensed temperature changes quantitatively as a function of time wherein said computer compares the temperature changes sensed in the heated region of the structure with previously determined temperature changes of a calibration sample having known disbond and inclusion characteristics to indicate disbonds and inclusion characteristics of the structure.
Claim 3
Dependent Claim
24 words
The thermographic detection system according to claim 1, further comprising an additional thermal sensor arranged non-linearly with respect to said plurality of thermal sensors.
Claim 4
Dependent Claim
20 words
The thermographic detection system according to claim 1, wherein each of said plurality of thermal sensors is a pyroelectric detector.
Claim 5
Dependent Claim
18 words
The thermographic detection system according to claim 1, further comprising a display which displays the assessed temperature changes.
Claim 6
Dependent Claim
25 words
The thermographic detection system according to claim 4, wherein said display displays a numerical value indicative of the disbond and inclusion characteristics of the structure.
Claim 7
Dependent Claim
25 words
The thermographic detection system according to claim 4, wherein said display displays a written description indicative of the disbond and inclusion characteristics of the structure.
Claim 8
Dependent Claim
25 words
The thermographic detection system according to claim 1, wherein the computer produces a numerical value indicative of the disbond and inclusion characteristics of the structure.
Claim 9
Dependent Claim
25 words
The thermographic detection system according to claim 1, wherein the computer produces a written description indicative of the disbond and inclusion characteristics of the structure.
References Cited (Backward Citations)
US2587705A
Cited
US3681970A
Cited
US3629584A
Cited
US4109508A
Cited
US4019364A
Cited
USRE32166E
Cited
US4309901A
Cited
US4439049A
Cited
US4854724A
Cited
US4647220A
Cited
US4644162A
Cited
US4933887A
Cited
US4928254A
Cited
US4854162A
Cited
US4950990A
Cited
US5052816A
Cited
US4999499A
Cited
US5131758A
Cited
US5250809A
Cited
US5246291A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-10-08 | 2000-04-08 | 2000-10-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-10-08 | 2004-04-08 | 2004-10-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-10-08 | 2008-04-08 | 2008-10-08 | $7700.00 | Window Closed / Lapsed |