US3592545A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for remote measurement of displacement of marks on a specimen undergoing a tensile test
Assignee: National Aeronautics and Space Administration
•
Filing: 1969-10-13
•
Granted: 1971-07-13
•
Expires: 1989-10-13
Abstract
Abstract Apparatus is disclosed for measuring displacement of marks on a specimen undergoing a tensile test comprising means for illuminating the field of marks, means for scanning the illuminated field with an oscillating mirror, or the like, a photosensitive detector, and means for recording in analog or digital form the time between detecting marks as the specimen undergoing testing is continuously scanned.
Inventors
- 👤 Robert H Silver
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:22
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/16
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
156 words
Apparatus for measuring the relative displacement between at least two visual marks on a given side of a specimen undergoing a tensile test, said mark being in the form of a narrow strip, comprising: a stationary opaque plate having a slit of substantially the same shape as said marks; means for illuminating said specimen on said side intended for viewing; means independent of said illuminating means for viewing said specimen on said side and for forming an optical image of a substantial portion of said side bearing said mark; means for reflecting said image onto said plate with the image marks parallel to said slit; means for cyclically driving said reflecting means to cyclically shift said image past said slit; a light-sensitive device behind said plate positioned to receive light through said slit; and means responsive to said light-sensitive device for displaying an electrical signal proportional to the intensity of light being received through said slit.
Claim 2
Dependent Claim
156 words
Apparatus for measuring the relative displacement between at least two visual marks on a given side of a specimen undergoing a tensile test, said mark being in the form of a narrow strip, comprising: a stationary opaque plate having a slit of substantially the same shape as said marks; means for illuminating said specimen on said side intended for viewing; means independent of said illuminating means for viewing said specimen on said side and for forming an optical image of a substantial portion of said side bearing said mark; means for reflecting said image onto said plate with the image marks parallel to said slit; means for cyclically driving said reflecting means to cyclically shift said image past said slit; a light-sensitive device behind said plate positioned to receive light through said slit; and means responsive to said light-sensitive device for displaying an electrical signal proportional to the intensity of light being received through said slit.
Claim 3
Dependent Claim
34 words
Apparatus as defined in claim 1 wherein said means for driving said reflecting means operates in an oscillatory manner whereby a given point in said image sweeps by said slit twice during each cycle.
Claim 4
Dependent Claim
49 words
Apparatus as defined in claim 1 wherein said means for cyclically driving said reflecting means includes means for generating a cycle-timing signal to indicate a reference instant of time in each cycle of operation, and said display means includes means for displaying said cycle-timing signal with said electrical signal.
References Cited (Backward Citations)
GB684435A
Cited
US3164008A
Cited
FR1379351A
Cited
US3454776A
Cited
US3421819A
Cited
US3435231A
Cited
US3439532A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-12 | 1975-01-11 | 1975-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-12 | 1979-01-11 | 1979-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-12 | 1983-01-11 | 1983-07-13 | $7700.00 | Window Closed / Lapsed |