US3890613A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Technique for minimizing loss of sensitivity of buried pressure responsive devices
Assignee: Westinghouse Electric Corp
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Filing: 1973-09-18
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Granted: 1975-06-17
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Expires: 1993-09-18
Abstract
Abstract A controlled application of an anti-freeze ingredient to soil covering a buried pressure responsive device such as an intrusion detector, eliminates reduction in sensitivity of the device due to frozen soil conditions. An alternate technique for avoiding frozen soil conditions consists of providing a thermal insulating enclosure for the soil between the ground surface and the pressure responsive device.
Inventors
- 👤 William K Dunsworth
- 👤 Fred G Geil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:35
CPC Classifications
E; E02; E02D; E02D31/00; G; G08; G08B; G08B13/00; G08B13/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
90 words
A method for minimizing loss of sensitivity of pressure responsive devices buried beneath the surface of the ground due to frozen soil conditions, comprising the steps of, adding an anti-freeze agent to a predetermined volume of previously untreated natural soil between a buried pressure responsive device and the surface of the ground, limiting the soil contacted by said anti-freeze agent to the soil defined within said predetermined volume, enclosing said pressure responsive device and said predetermined volume of soil within a non-porous enclosure, and covering said enclosure with untreated soil.
Claim 2
Independent Claim
90 words
A method for minimizing loss of sensitivity of pressure responsive devices buried beneath the surface of the ground due to frozen soil conditions, comprising the steps of, adding an anti-freeze agent to a predetermined volume of previously untreated natural soil between a buried pressure responsive device and the surface of the ground, limiting the soil contacted by said anti-freeze agent to the soil defined within said predetermined volume, enclosing said pressure responsive device and said predetermined volume of soil within a non-porous enclosure, and covering said enclosure with untreated soil.
References Cited (Backward Citations)
US950270A
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US2007969A
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US2162185A
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US3438021A
Cited
US3648520A
Cited
US3675432A
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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) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |