US3759331A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fire protection system utilizing dry pipes normally maintained in a vacuum
Assignee: Factory Mutual Research Corp
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Filing: 1972-04-27
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Granted: 1973-09-18
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Expires: 1992-04-27
Abstract
Abstract A fire protection system in which a plurality of extinguishant discharge heads are disposed in elevated position in a space to be protected from fire and are connected by a piping system for supplying extinguishant to the heads. Flow of extinguishant to the heads is normally prevented until a predetermined increase in fluid pressure is affected in the piping system in response to a fire condition in the space.
Inventors
- 👤 W Livingston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 23:06
CPC Classifications
A; A62; A62C; A62C35/00; A62C35/58; A62C35/60; A62C35/605
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
112 words
A fire protection system comprising a plurality of discharge heads disposed in an elevated position in a space to Be protected from fire, a piping system connecting said heads, a source of extinguishant connected to said piping system, means for normally maintaining the fluid pressure in said piping system below a predetermined maximum value, control means normally preventing the flow of extinguishant from said source to said heads, said control means being responsive to an increase in said fluid pressure above said maximum value for permitting the flow of extinguishant to said heads, and means responsive to a predetermined fire condition in said space for causing said increase in said fluid pressure.
Claim 2
Dependent Claim
112 words
A fire protection system comprising a plurality of discharge heads disposed in an elevated position in a space to Be protected from fire, a piping system connecting said heads, a source of extinguishant connected to said piping system, means for normally maintaining the fluid pressure in said piping system below a predetermined maximum value, control means normally preventing the flow of extinguishant from said source to said heads, said control means being responsive to an increase in said fluid pressure above said maximum value for permitting the flow of extinguishant to said heads, and means responsive to a predetermined fire condition in said space for causing said increase in said fluid pressure.
Claim 3
Dependent Claim
17 words
The system of claim 1 wherein said predetermined maximum value of said fluid pressure is atmospheric pressure.
Claim 4
Dependent Claim
24 words
The system of claim 1 wherein said means for causing said increase in said pressure comprises means for venting said piping system to atmosphere.
Claim 5
Dependent Claim
19 words
The system of claim 3 wherein said venting means comprises a venting assembly associated with each of said heads.
Claim 6
Dependent Claim
77 words
The system of claim 4 wherein each venting assembly comprises a spring loaded cap extending over the outlet of its respective head, a thermal link normally maintaining its respective cap in an extinguishant discharge preventing position relative to said outlet, each of said links adapted to release its respective cap in response to said predetermined fire condition, whereby said cap moves from said extinguishant discharge preventing position to a venting position by virtue of its spring force.
Claim 7
Dependent Claim
32 words
The system of claim 1 wherein said means for normally maintaining the fluid pressure in said piping system below a predetermined maximum value comprises a vacuum pump connected to said piping system.
Claim 8
Dependent Claim
50 words
The system of claim 1 wherein said control means comprises a pinch valve disposed in said piping system, and an actuator responsive to the pressure in said piping system being below said predetermined maximum value for closing said valve, and responsive to said increase in pressure for opening said valve.
Claim 9
Dependent Claim
24 words
The system of claim 7 wherein said means for causing said increase in said pressure comprises means for venting said piping system to atmosphere.
Claim 10
Dependent Claim
50 words
The system of claim 7 wherein said actuator comprises a housing, a diaphragm defining a chamber in said housing and movable in said housing in response to fluid pressure variations in said chamber, means connecting said diaphragm to said pinch valve, and means communicating said chamber with said piping system.
References Cited (Backward Citations)
US2357133A
Cited
US2590215A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-17 | 1977-03-19 | 1977-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-17 | 1981-03-19 | 1981-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-17 | 1985-03-19 | 1985-09-18 | $7700.00 | Window Closed / Lapsed |