Patent US3251289A successfully refreshed from Google Patents.
US3251289A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wedge-shaped plenum chamber
Assignee: Armstrong World Industries Inc
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Filing: 1963-04-10
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Granted: 1966-05-17
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Expires: 1983-04-10
Abstract
No abstract record available.
Inventors
- 👤 Mariner Thomas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:54
CPC Classifications
F; F24; F24F; F24F7/00; F24F7/04; F24F7/06; F24F7/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
111 words
A BUILDING UNIT FOR FORMING THE CEILING OF A ROOM, SAID UNIT HAVING A TOP, BOTTOM AND SIDES FORMING A CHAMBER WHICH IS OPEN AT ONE END FOR THE INTRODUCTION OF VENTILATING AIR THERETO, THE BOTTOM OF SAID CHAMBER BEING PROVIDED WITH OPENINGS FOR THE CONDITION OF VENTILATING AIR THERETHROUGH TO THE ROOM BENEATH, THE TOP OF THE UNIT SLOPING FROM ONE END FOR A SUBSTANTIAL PORTION OF THE ENTIRE LENGTH OF THE UNIT SO AS TO FORM A CHAMBER IN WHICH THE DECREASE IN CROSS-SECTIONAL AREA IS PROPORTIONAL TO THE DISTANCE FROM THE OPEN END OF THE UNIT, THE BOTTOM SURFACE OF SAID UNIT BEING FORMED OF A SOUND-ABSORBING MATERIAL.
Claim 2
Dependent Claim
111 words
A BUILDING UNIT FOR FORMING THE CEILING OF A ROOM, SAID UNIT HAVING A TOP, BOTTOM AND SIDES FORMING A CHAMBER WHICH IS OPEN AT ONE END FOR THE INTRODUCTION OF VENTILATING AIR THERETO, THE BOTTOM OF SAID CHAMBER BEING PROVIDED WITH OPENINGS FOR THE CONDITION OF VENTILATING AIR THERETHROUGH TO THE ROOM BENEATH, THE TOP OF THE UNIT SLOPING FROM ONE END FOR A SUBSTANTIAL PORTION OF THE ENTIRE LENGTH OF THE UNIT SO AS TO FORM A CHAMBER IN WHICH THE DECREASE IN CROSS-SECTIONAL AREA IS PROPORTIONAL TO THE DISTANCE FROM THE OPEN END OF THE UNIT, THE BOTTOM SURFACE OF SAID UNIT BEING FORMED OF A SOUND-ABSORBING MATERIAL.
References Cited (Backward Citations)
US1423297A
Cited
US1863949A
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US2172944A
Cited
US2251617A
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US2329102A
Cited
US3115819A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-05-16 | 1969-11-15 | 1970-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-05-16 | 1973-11-15 | 1974-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-05-16 | 1977-11-15 | 1978-05-17 | $7700.00 | Window Closed / Lapsed |