US3710746A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Buoyancy lifting devices
Assignee: Cammell Laird and Co Ltd
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Filing: 1971-01-29
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Granted: 1973-01-16
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Expires: 1991-01-29
Abstract
Abstract A buoyancy operated lifting and/or lowering device comprises a hollow body, means for flooding said hollow body, means for charging the hollow body with gas and at least one gas pressure relief tube extending downwardly from the upper or gas containing portion of the hollow body to a position below said hollow body. The gas pressure relief tube relieves pressure in the hollow body, as the device ascends and the ambient pressure to which the hollow body is subjected decreases. The buoyancy of the device is thereby maintained substantially constant during said ascent. The inlet for charging the hollow body with gas may have a valve which is responsive to the ambient pressure to which the hollow body is subjected. The buoyancy of the device is thereby maintained substantially constant during its descent.
Inventors
- 👤 Donald I Mc
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:00
CPC Classifications
B; B63; B63C; B63C7/00; B63C7/06; B63C7/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
210 words
A buoyancy operated lifting and/or lowering device comprising a closed hollow body, valve controlled means at the lower part of said hollow body whereby it may be flooded when immersed in a body of water so as to cause it to descend, valve controlled means at the upper part of the hollow body for discharging gas therefrom during said flooding of the hollow body, gas supply means connected to the upper part of the hollow body for charging it with gas to displace water from the interior of the hollow body to adjust its buoyancy, a pressure sensitive valve means in said gas supply means and positioned on the hollow body so as to respond to the changing hydrostatic pressure on the hollow body during its descent and provide a gas flow to the hollow body to maintain the internal pressure balance therein so that the water level in and buoyancy of the hollow body will not change during its descent, and a gas pressure relief means connected to the upper part of the hollow body, said gas pressure relief means providing for the discharge of gas from the hollow body during its ascent, whereby the internal pressure within the body is maintained substantially the same as the ambienT pressure.
Claim 2
Dependent Claim
210 words
A buoyancy operated lifting and/or lowering device comprising a closed hollow body, valve controlled means at the lower part of said hollow body whereby it may be flooded when immersed in a body of water so as to cause it to descend, valve controlled means at the upper part of the hollow body for discharging gas therefrom during said flooding of the hollow body, gas supply means connected to the upper part of the hollow body for charging it with gas to displace water from the interior of the hollow body to adjust its buoyancy, a pressure sensitive valve means in said gas supply means and positioned on the hollow body so as to respond to the changing hydrostatic pressure on the hollow body during its descent and provide a gas flow to the hollow body to maintain the internal pressure balance therein so that the water level in and buoyancy of the hollow body will not change during its descent, and a gas pressure relief means connected to the upper part of the hollow body, said gas pressure relief means providing for the discharge of gas from the hollow body during its ascent, whereby the internal pressure within the body is maintained substantially the same as the ambienT pressure.
Claim 3
Dependent Claim
51 words
A buoyancy operated lifting and/or lowering device as claimed in claim 1 wherein the gas pressure relief means comprises at least one open-ended relief tube connected to the upper part of the hollow body and extending downwardly therefrom so that its open end is below the bottom of the hollow body.
Claim 4
Dependent Claim
36 words
A buoyancy operated lifting and/or lowering device as claimed in claim 1 whereas the gas supply means is at least one bottle of gas and means is provided on the hollow body mounting said bottle thereon.
Claim 5
Dependent Claim
43 words
A buoyancy operated lifting and/or lowering device as claimed in claim 1 wherein there is an adjustable flow control valve in the gas supply means whereby the gas supply can be adjusted to deliver gas at a predetermined pressure above the ambient pressure.
Claim 6
Dependent Claim
32 words
A buoyancy operated lifting and/or lowering device as claimed in claim 1 wherein the pressure sensitive valve means has a diaphragm which is subjected, on one side, to the ambient water pressure.
Claim 7
Dependent Claim
24 words
A buoyancy operated lifting and/or lowering device as claimed in claim 1 wherein there is a relief valve in the gas pressure relief means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-16 | 1976-07-17 | 1977-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-16 | 1980-07-17 | 1981-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-16 | 1984-07-17 | 1985-01-16 | $7700.00 | Window Closed / Lapsed |