Patent US4200920A successfully refreshed from Google Patents.
US4200920A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Artificial underwater target
Assignee: United States Department of the Navy
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Filing: 1956-02-29
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Granted: 1980-04-29
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Expires: 1976-02-29
Abstract
Abstract 1. In combination in a free, underwater craft, a hull, means for carrying llast, means for discharging said ballast, depth responsive means, a timer providing two time intervals, control means operated by said timer for actuating said discharging means after a pre-set time interval, and other control means operated by both said timer and said depth reponsive means for actuating said discharge means after a shorter time interval if said craft attains a pre-set depth.
Inventors
- 👤 David J. Evans
- 👤 Clark F. Bradley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:48
CPC Classifications
B; B63; B63G; B63G8/00; B63G8/14; B63G8/22; B63G8/28; B63G8/34; B06; B06B; B06B2201/00; B06B2201/70; B06B2201/74
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
74 words
In combination in a free, underwater craft, a hull, means for carrying ballast, means for discharging said ballast, depth responsive means, a timer providing two time intervals, control means operated by said timer for actuating said discharging means after a pre-set time interval, and other control means operated by both said timer and said depth responsive means for actuating said discharge means after a shorter time interval if said craft attains a pre-set depth.
Claim 2
Dependent Claim
74 words
In combination in a free, underwater craft, a hull, means for carrying ballast, means for discharging said ballast, depth responsive means, a timer providing two time intervals, control means operated by said timer for actuating said discharging means after a pre-set time interval, and other control means operated by both said timer and said depth responsive means for actuating said discharge means after a shorter time interval if said craft attains a pre-set depth.
References Cited (Backward Citations)
US1097700A
Cited
US1348152A
Cited
US1527782A
Cited
US1515195A
Cited
US1803530A
Cited
US2409169A
Cited
US2411393A
Cited
US2447651A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-04-29 | 1983-10-29 | 1984-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-29 | 1987-10-29 | 1988-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-29 | 1991-10-29 | 1992-04-29 | $7700.00 | Window Closed / Lapsed |