US3680329A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure equalizing valve
Assignee: HILL REFRIGERATION Corp A CORP OF CA
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Filing: 1971-02-18
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Granted: 1972-08-01
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Expires: 1991-02-18
Abstract
Abstract Refrigerated equipment is provided with an air passage through a wall thereof. A closure member within the passage is movable in opposite directions in response to overpressure or under pressure created within the refrigerated space upon opening or closing of a door. The closure member substantially completely closes the passage and means are provided for preventing the formation of ice between the sides of the passage and the closure which might otherwise interfere with the movement of the closure.
Inventors
- 👤 Winfield R Burtis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:59
CPC Classifications
F; F25; F25D; F25D17/00; F25D17/04; F25D17/042; F25D17/047; Y; Y10; Y10T; Y10T137/00; Y10T137/3149
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
100 words
A refrigerated cabinet comprising an enclosure having a door, operatively mounted therein; said cabinet having at least one generally upright wall; a passageway defined entirely through said upright wall to communicate an interior space, defined by said cabinet, with ambient; a valve member hingedly mounted within said passageway; said valve member normally serving to substantially block said passageway and being operable to swing open, in either direction, in response to a pressure differential being established across said valve member; and a cover member mounted to extend over said passageway in spaced, generally parallel relationship with respect to said upright wall.
Claim 2
Dependent Claim
100 words
A refrigerated cabinet comprising an enclosure having a door, operatively mounted therein; said cabinet having at least one generally upright wall; a passageway defined entirely through said upright wall to communicate an interior space, defined by said cabinet, with ambient; a valve member hingedly mounted within said passageway; said valve member normally serving to substantially block said passageway and being operable to swing open, in either direction, in response to a pressure differential being established across said valve member; and a cover member mounted to extend over said passageway in spaced, generally parallel relationship with respect to said upright wall.
Claim 3
Dependent Claim
52 words
A refrigerated cabinet according to claim No. 1, wherein: said passageway is defined by a conduit, comprising a heat conductive material; said conduit cooperates with internal portions of said generally upright wall to define an inner space disposed contiguous to said conduit; and heating means is operatively disposed within said inner space.
Claim 4
Dependent Claim
73 words
A refrigerated cabinet according to claim No. 1, wherein: said passageway is defined by a conduit having a portion, protruding generally, normally, outwardly from an outer surface of said generally upright wall; marginal edges of said cover member being formed with flanges extending generally normally from said cover element and toward said upright wall, adjacent said protruding portion of said conduit; and marginal edges of said flanges being spaced from said upright wall.
Claim 5
Dependent Claim
22 words
A refrigerated cabinet according to claim No. 1, wherein: said passageway is formed to extend generally horizontally through said generally upright wall.
Claim 6
Independent Claim
19 words
An apparatus according to claim No. 2, wherein said heating means comprises at least one electrical resistance heating element.
Claim 7
Dependent Claim
30 words
A refrigerated cabinet according to Claim No. 4, wherein said valve is mounted to hinge about a generally horizontal axis extending generally transversely across an upper portion of said passageway.
References Cited (Backward Citations)
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Cited
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Cited
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Cited
US2798422A
Cited
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Cited
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Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |