US3840208A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bubble-tight inflatable seal for butterfly valve with offset disc
Assignee: Individual
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Filing: 1973-05-10
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Granted: 1974-10-08
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Expires: 1993-05-10
Abstract
Abstract An off-set disc pivotally mounted in a butterfly valve body is pivotable from an open position to a bubble-tight or leak-proof, closed position. A continuous, integral inflatable seal having opposed inwardly concave sides is disposed within the valve body in sealing relationship with the periphery of the disc by a unique seal-retaining means which permits no leakage of gas and easy replacement of the seal. The inflatable seal is secured between a pair of spaced-apart annular rings by friction between mating portions of the rings and the seal. When not inflated the seal may be removed from between the rings simply by pulling it out. Means are provided for inflating the seal to a predetermined pressure.
Inventors
- 👤 A Schudel
- 👤 R Rodwancy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:53
CPC Classifications
F; F16; F16K; F16K1/00; F16K1/16; F16K1/18; F16K1/22; F16K1/226; F16K1/228
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
178 words
In a butterfly valve to control the flow of gas in a duct, said valve including a valve body having oppositely disposed bores and a shaft rotatably mounted within said bores, an off-set disc longitudinally spaced apart from and rigidly affixed to said shaft and rotatable to present the periphery of the disc into and out of sealing relationship with the sealing surface of an inflatable seal secured in a retaining means disposed upon the inner wall of said valve body, the improvement comprising: a. a continuous, integral inflatable seal having a convex sealing surface when inflated, and arcuate, inwardly concave, sides disposed intermediate b. a pair of annular retaining rings disposed in parallel spaced-apart relationship upon said inner wall, said rings having opposed inside surfaces adapted to contact and frictionally secure said arcuate sides of said seal, and c. means for inflating said seal to a internal seal pressure in excess of the pressure of said gas to effect a bubble-tight seal between said periphery of the disc and said convex sealing surface of the inflated seal.
Claim 2
Dependent Claim
178 words
In a butterfly valve to control the flow of gas in a duct, said valve including a valve body having oppositely disposed bores and a shaft rotatably mounted within said bores, an off-set disc longitudinally spaced apart from and rigidly affixed to said shaft and rotatable to present the periphery of the disc into and out of sealing relationship with the sealing surface of an inflatable seal secured in a retaining means disposed upon the inner wall of said valve body, the improvement comprising: a. a continuous, integral inflatable seal having a convex sealing surface when inflated, and arcuate, inwardly concave, sides disposed intermediate b. a pair of annular retaining rings disposed in parallel spaced-apart relationship upon said inner wall, said rings having opposed inside surfaces adapted to contact and frictionally secure said arcuate sides of said seal, and c. means for inflating said seal to a internal seal pressure in excess of the pressure of said gas to effect a bubble-tight seal between said periphery of the disc and said convex sealing surface of the inflated seal.
Claim 3
Dependent Claim
58 words
The combination of claim 1 wherein said rings comprise rods welded to said inner wall and the rings on the upstream side of said flow of gas is continuously welded to said inner wall, and the distance between the inner edges of said rings is less than the width of the base of said continuous integral inflatable seal.
Claim 4
Dependent Claim
23 words
The combination of claim 1 wherein the height of each said ring is less than the height of said seal in uninflated condition.
Claim 5
Dependent Claim
28 words
The combination of claim 1 wherein said internal seal pressure is less than about 100 psig and said pressure of said gas is less than about 25 psig.
Claim 6
Dependent Claim
34 words
The combination of claim 1 including operator means for rotating said shaft and disc from an open position to a closed position, or vice versa, and automatically pressurizing and depressurizing said seal, as desired.
Claim 7
Dependent Claim
16 words
The combination of claim 1 wherein said inflatable seal is removably secured intermediate said retaining means.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-07 | 1978-04-08 | 1978-10-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-07 | 1982-04-08 | 1982-10-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-07 | 1986-04-08 | 1986-10-08 | $7700.00 | Window Closed / Lapsed |