Patent US4279540A successfully refreshed from Google Patents.
US4279540A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Collapsable dam
Assignee: KAZUTO NAKAZAWA GENERAL DIRECTOR PUBLIC WORKS RESEARCH INSTITUTE MINISTRY OF CONSTRUCTION
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Filing: 1979-02-09
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Granted: 1981-07-21
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Expires: 1999-02-09
Abstract
Abstract A deformable dam made of an impermeable flexible membrane secured in a water tight manner to the bottom and side walls of a river. The flexible membrane is inflatable using either air or water, or a combination to vary the overall effective length of the dam.
Inventors
- 👤 Kyozo Suga
- 👤 Jinya Iizuka
- 👤 Yoshiomi Tsuji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:46
CPC Classifications
E; E02; E02B; E02B7/00; E02B7/005
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
92 words
In a deformable dam having an impermeable flexible membrane wall which is water-tightly secured to the bottom and side walls of a river, the improvement comprising: said impermeable flexible membrane wall including at least one hollow bag forming a part of said wall, and means for selective charging and discharging the hollow bag with a fluid to thereby vary the effective height and length of said dam and prevent the accumulation of alluvial material under said flexible membrane by having the alluvial material removed by the flow of water over the dam.
Claim 2
Dependent Claim
92 words
In a deformable dam having an impermeable flexible membrane wall which is water-tightly secured to the bottom and side walls of a river, the improvement comprising: said impermeable flexible membrane wall including at least one hollow bag forming a part of said wall, and means for selective charging and discharging the hollow bag with a fluid to thereby vary the effective height and length of said dam and prevent the accumulation of alluvial material under said flexible membrane by having the alluvial material removed by the flow of water over the dam.
Claim 3
Dependent Claim
24 words
The deformable dam of claim 1 wherein said flexible membrane comprises a plurality of hollow cylindrical bodies, said bodies being coupled to each other.
Claim 4
Dependent Claim
35 words
The deformable dam of claim 1 wherein said flexible membrane comprises a plurality of hollow convex wall shaped bodies, said convex bodies being coupled to each other at the edge juncture of each convex wall.
Claim 5
Dependent Claim
18 words
The deformable dam of claims 1, 2 or 3 wherein said flexible membrane comprises a rubber coated sheet.
Claim 6
Dependent Claim
36 words
The deformable dam of claim 1 further comprising a solid base disposed on the bottom of said river, said base having a recess portion, said membrane being secured to said base in the recess portion thereof.
Claim 7
Dependent Claim
12 words
The deformable dam of claim 1 wherein said charging fluid is air.
Claim 8
Dependent Claim
21 words
The deformable dam of claim 1 wherein said flexible membrane comprises a plurality of hollow spheres, said spheres laterally joined together.
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) | 1984-07-20 | 1985-01-19 | 1985-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-07-20 | 1989-01-19 | 1989-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-07-20 | 1993-01-19 | 1993-07-21 | $7700.00 | Window Closed / Lapsed |