US3592207A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air duct closure
Assignee: RICHARD A BORELLO
•
Filing: 1969-05-12
•
Granted: 1971-07-13
•
Expires: 1989-05-12
Abstract
Abstract A closure for a ventilating or heating duct comprises a plug or pillow of a foamed plastic automatically injected into the duct by a propellant, through a temperature sensitive valve which opens at a predetermined temperature as in case of fire.
Inventors
- 👤 Richard A Borello
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:58
CPC Classifications
A; A62; A62C; A62C2/00; A62C2/06; Y; Y10; Y10T; Y10T137/00; Y10T137/0318; Y10T137/1624; Y10T137/1797; Y10T137/1819
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
94 words
An apparatus for closing an air duct in case of fire comprising a container attached to an air duct, a foam-generating liquid capable of forming an adherent plastic foam mass, held under pressure by a propellant gas within said container, a conduit leading from the outlet of said container into said duct, and a closure for said conduit controlled by a temperature sensitive element set to release said closure at a predetermined temperature, whereupon a mass of adherent plastic foam is injected into said duct effectively closing it to the passage of air therethrough.
Claim 2
Dependent Claim
15 words
The apparatus of claim 2 wherein said temperature sensitive element is a fusible metal link.
Claim 3
Dependent Claim
45 words
The apparatus of claim 2 wherein said temperature sensitive element is a fusible metal link and said closure is sealed to said conduit with a fusible solder having a melting point about 5* F. to 15* F. below the melting point of said fusible link.
Claim 4
Dependent Claim
48 words
The apparatus of claim 2 wherein a second container is provided having an outlet contiguous with the outlet of said foam-generating container and a closure therefor integral with the closure of said first container, both said closures being opened simultaneously by the action of said temperature sensitive element.
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) | 1974-07-12 | 1975-01-11 | 1975-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-12 | 1979-01-11 | 1979-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-12 | 1983-01-11 | 1983-07-13 | $7700.00 | Window Closed / Lapsed |