US3722899A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Seal
Assignee: General Engineering Co Ltd
•
Filing: 1971-08-03
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Granted: 1973-03-27
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Expires: 1991-08-03
Abstract
Abstract This invention provides a seal for closing an entry or exit aperture of an apparatus in which a moving strip of material is to be treated while in either a partial vacuum or while in a pressurized container, the seal serving completely to close the entry or exit aperture periodically and to deform as the material under treatment moves so that no appreciable drag is imparted to the material and then to open slightly to allow the seal to become undeformed before closing again upon the material so that the increments of time for which the seal is open are small and thus passage of fluid across the seal is minimized thereby to enable the required degree of vacuum or pressure to be maintained without imposing undue stress upon the mechanism used to create the vacuum or pressure conditions required.
Inventors
- 👤 A Sedwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:53
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/22; C23C14/56; C23C14/562; F; F16; F16J; F16J15/00; F16J15/16; F16J15/168; Y; Y10; Y10S; Y10S277/00; Y10S277/906; Y10S277/913
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
147 words
A seal including at least one pair of relatively movable Shutters, deformable edge regions for each of said shutters along adjacent edges of said shutters, means associated with at least one of the shutters of the at least one pair of shutters to cause movement thereof alternatively towards and then away from the other shutter of the pair and to retain the shutters in close proximity with each other for an increment of time so as, in use, to cause the said deformable edge regions of the said shutters to contact a material as it is passed through said seal, the said increment of time being that taken fully to deform said deformable edge regions of said shutters, and then to separate the shutters to allow said deformable edges to return to an undeformed condition before they again become located in said close proximity with each other.
Claim 2
Dependent Claim
147 words
A seal including at least one pair of relatively movable Shutters, deformable edge regions for each of said shutters along adjacent edges of said shutters, means associated with at least one of the shutters of the at least one pair of shutters to cause movement thereof alternatively towards and then away from the other shutter of the pair and to retain the shutters in close proximity with each other for an increment of time so as, in use, to cause the said deformable edge regions of the said shutters to contact a material as it is passed through said seal, the said increment of time being that taken fully to deform said deformable edge regions of said shutters, and then to separate the shutters to allow said deformable edges to return to an undeformed condition before they again become located in said close proximity with each other.
Claim 3
Dependent Claim
25 words
A seal as set forth in claim 1 in which both shutters of a pair of shutters are associated with means for causing movement thereof.
Claim 4
Dependent Claim
35 words
A seal as set forth in claim 1 in which the means for causing shutter movement includes electrical apparatus adapted to produce a square wave output signal, said signal serving to control said shutter movement.
Claim 5
Dependent Claim
53 words
A seal as set forth in claim 1 in which the means for causing shutter movement includes electrical apparatus adapted to produce a square wave output signal, an eccentric, a link from said eccentric to said shutter and means for causing movement of said eccentric by said output signal from said electrical apparatus.
Claim 6
Dependent Claim
20 words
A seal as set forth in claim 1 in which said deformable edge regions of said shutters are soft rubber.
Claim 7
Dependent Claim
23 words
A seal as set forth in claim 1 in which said deformable edge regions of said shutters are circular in cross-section when undeformed.
Claim 8
Dependent Claim
34 words
A seal as set forth in claim 1 in which two pairs of shutters are provided, said shutters of one pair being movable 180* out of phase with said shutters of said other pair.
Claim 9
Dependent Claim
51 words
A seal as set forth in claim 1 in which said shutters are slidable in slides in a wall of a chamber through which a strip of material is to pass, means being provided in association with said chamber to create and maintain a pressure therein different to prevailing atmospheric pressure.
Claim 10
Dependent Claim
28 words
A seal as set forth in claim 8 in which said means associated with said chamber is adapted to provide and maintain a sub-atmospheric pressure in said chamber.
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) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |