Patent US4100931A successfully refreshed from Google Patents.
US4100931A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fire damper
Assignee: Individual
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Filing: 1976-07-12
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Granted: 1978-07-18
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Expires: 1996-07-12
Abstract
Abstract A fire damper of the kind in which at least one flap is pivoted in a duct between a first position in which the flap closes the duct and a second position in which the duct is open. A suitably powered winching motor is adapted to control the movement of the flap through a linkage including a fusible link so that when the motor is energized the flap is moved to its second position or open position provided that the fusible link is still intact whereas when the motor is de-energized the flap is moved to its first or closed position.
Inventors
- 👤 Frederick William Pantland
- 👤 Ernest Francis Pantland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:40
CPC Classifications
A; A62; A62C; A62C2/00; A62C2/06; A62C2/12; A62C2/14; A62C2/24; A62C2/241; A62C2/242; F; F16; F16K; F16K17/00; F16K17/36; F16K17/38; F16K17/383; F24; F24F; F24F11/00; F24F11/30; F24F11/32; F24F11/33; F24F11/35; Y; Y10; Y10T; Y10T137/00; Y10T137/1624; Y10T137/1797; Y10T137/1819; Y10T137/1834
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
151 words
A fire damper comprising an orifice, at least one flap pivoted in the orifice between a first position in which it closed the orifice and a second position in which the orifice is fully open, a winching motor, a motion transmitting linkage operable by the motor and including a fusible link, one end of the linkage being connected to the flap, the motor being adapted to be energized by compressed air fed through a solenoid controlled valve so that energization of the motor causes the flap to open provided that the fusible link is still intact whereas de-energization of the motor causes the flap to close, and a smoke detector adapted to close the valve in the presence of smoke and thereby cause the motor to become de-energized, said smoke detector being further adapted to open the valve in the absence of smoke and thereby cause the motor to become energized.
Claim 2
Dependent Claim
151 words
A fire damper comprising an orifice, at least one flap pivoted in the orifice between a first position in which it closed the orifice and a second position in which the orifice is fully open, a winching motor, a motion transmitting linkage operable by the motor and including a fusible link, one end of the linkage being connected to the flap, the motor being adapted to be energized by compressed air fed through a solenoid controlled valve so that energization of the motor causes the flap to open provided that the fusible link is still intact whereas de-energization of the motor causes the flap to close, and a smoke detector adapted to close the valve in the presence of smoke and thereby cause the motor to become de-energized, said smoke detector being further adapted to open the valve in the absence of smoke and thereby cause the motor to become energized.
Claim 3
Dependent Claim
20 words
A fire damper as claimed in claim 1 in which interruption of the fusible link causes the flap to close.
Claim 4
Dependent Claim
19 words
A fire damper as claimed in claim 1 in which the winching motor comprises a pneumatically-operable piston and cylinder.
Claim 5
Dependent Claim
41 words
A fire damper as claimed in claim 1 in which the motion transmitting linkage is a cable, one end of which is attached to the flap and the other end of which is anchored to fixed structure through the fusible link.
Claim 6
Dependent Claim
36 words
A fire damper as claimed in claim 1 in which the flap is latched closed in the first position, the flap being unlatched when the motor is energized, provided that the fusible link is still intact.
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) | 1981-07-17 | 1982-01-16 | 1982-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-17 | 1986-01-16 | 1986-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-17 | 1990-01-16 | 1990-07-18 | $7700.00 | Window Closed / Lapsed |