US4041771A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Temperature-sensitive detector
Assignee: Arthur D Little Inc
•
Filing: 1975-05-09
•
Granted: 1977-08-16
•
Expires: 1995-05-09
Abstract
Abstract An improved versatile device which is useful in detecting leaks of cyrogenic material from transporting, storage and processing equipment and for indicating the location of the leaks.
Inventors
- 👤 Donald S. Allan
- 👤 Daniel Schiff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:49
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/02; G01M3/04; G01M3/16; G01M3/18; F; F17; F17C; F17C13/00; F17C13/12; G01K; G01K11/00; G01K11/06; G01M3/002; F17C2221/00; F17C2221/03; F17C2221/032; F17C2221/033; F17C2221/035; F17C2223/00; F17C2223/01; F17C2223/0146; F17C2223/0153; F17C2223/0161; F17C2223/03; F17C2223/033; F17C2250/00; F17C2250/03; F17C2250/036; F17C2260/00; F17C2260/03; F17C2260/035; F17C2260/038
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
172 words
A leak detector for a first container adapted for holding a first body of material at temperatures which are different from ambient temperature, said detector comprising in combination: an elongated tube of an electrically nonconductive material, said tube being adapted to be distributed along the exterior of said first container; a second body of a second material in said tube, said second body being normally of a first electrical conductivity in a first phase at ambient temperature and capable of exhibiting at a predetermined temperature between said ambient temperature and said temperatures of said first body of material, a local change in phase and electrical conductivity between said first phase and a second phase at a location where said predetermined temperature occurs; and means for sensing the location of said local change in phase in said elongated tube, said means for sensing comprising elongated electrically-conductive means disposed along said tube and means for measuring from one end of said tube, the electrical capacitance between said elongated electrically-conductive means and said second material.
Claim 2
Dependent Claim
172 words
A leak detector for a first container adapted for holding a first body of material at temperatures which are different from ambient temperature, said detector comprising in combination: an elongated tube of an electrically nonconductive material, said tube being adapted to be distributed along the exterior of said first container; a second body of a second material in said tube, said second body being normally of a first electrical conductivity in a first phase at ambient temperature and capable of exhibiting at a predetermined temperature between said ambient temperature and said temperatures of said first body of material, a local change in phase and electrical conductivity between said first phase and a second phase at a location where said predetermined temperature occurs; and means for sensing the location of said local change in phase in said elongated tube, said means for sensing comprising elongated electrically-conductive means disposed along said tube and means for measuring from one end of said tube, the electrical capacitance between said elongated electrically-conductive means and said second material.
Claim 3
Dependent Claim
27 words
A leak detector in accordance with claim 1, wherein said first phase of said second material is a liquid phase and said second phase is solid phase.
Claim 4
Dependent Claim
19 words
A leak detector in accordance with claim 2, wherein the freezing temperature of said second material is substantially fixed.
Claim 5
Dependent Claim
30 words
A leak detector in accordance with claim 1, wherein said second material is of a first conductivity in said first phase and of a different conductivity in said second phase.
Claim 6
Dependent Claim
26 words
A leak detector in accordance with claim 1, wherein said means surrounding said tube comprises an electrically conductive sheath made of a flexible metal mesh material.
Claim 7
Dependent Claim
235 words
A leak detector for a first container adapted for holding a first body of material at temperatures which are different from ambient temperature and comprising in combination: an elongated container adapted to be distributed along the exterior of said first container; a second body of a second material in said elongated container, said second body being normally in a first phase at ambient temperature and capable of exhibiting at a predetermined temperature between said ambient temperature and said temperatures of said first body of material, a local phase change between said first phase and a second phase at a location where said predetermined temperature occurs, said second body comprising two or more components, one of said components exhibiting, per se at a first temperature different than said predetermined temperature, the same change of phase as said local phase change, the other of said components exhibiting per se at a second temperature different from said predetermined temperature the same change of phase as said local phase change, said components being miscible with one another so that a homogenous chemical composition is maintained through said phase change; and means for sensing the location of said local phase change in said elongated container, said means for sensing comprising an elongated electrically-conductive sheath disposed along said tube and means for measuring from one end of said tube, the capacitance between said elongated electrically conductive sheath and said second material.
Claim 8
Dependent Claim
235 words
A leak detector for a first container adapted for holding a first body of material at temperatures which are different from ambient temperature and comprising in combination: an elongated container adapted to be distributed along the exterior of said first container; a second body of a second material in said elongated container, said second body being normally in a first phase at ambient temperature and capable of exhibiting at a predetermined temperature between said ambient temperature and said temperatures of said first body of material, a local phase change between said first phase and a second phase at a location where said predetermined temperature occurs, said second body comprising two or more components, one of said components exhibiting, per se at a first temperature different than said predetermined temperature, the same change of phase as said local phase change, the other of said components exhibiting per se at a second temperature different from said predetermined temperature the same change of phase as said local phase change, said components being miscible with one another so that a homogenous chemical composition is maintained through said phase change; and means for sensing the location of said local phase change in said elongated container, said means for sensing comprising an elongated electrically-conductive sheath disposed along said tube and means for measuring from one end of said tube, the capacitance between said elongated electrically conductive sheath and said second material.
References Cited (Backward Citations)
US2460688A
Cited
US2558063A
Cited
US2820196A
Cited
US3214963A
Cited
US3273379A
Cited
US3316752A
Cited
US3510762A
Cited
US3588689A
Cited
US3914688A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-08-15 | 1981-02-14 | 1981-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-15 | 1985-02-14 | 1985-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-15 | 1989-02-14 | 1989-08-16 | $7700.00 | Window Closed / Lapsed |