US3884133A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fire control system for multi-zone buildings
Assignee: Individual
•
Filing: 1974-08-21
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Granted: 1975-05-20
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Expires: 1994-08-21
Abstract
Abstract A method of controlling smoke, ventilation and fire flash point temperature in a multi-zone building served by a central ventilation system uses a divided common return air duct having separate branch damper connections for each zone for directing all return air from a fire zone into one section of the common return air duct for complete exhaust and for directing all return air from a non-fire zone into the other section of the common return air duct. The method also provides positive pressurization of the non-fire ventilation zones relative to the fire ventilation zones and maximum fresh air to all zones.
Inventors
- 👤 Edward J Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:30
CPC Classifications
A; A62; A62C; A62C2/00; A62C2/06
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
266 words
In a multi-zone building having a ventilation system that includes a central station serving a plurality of ventilation zones, common supply air duct means connecting the central station to the ventilation zones, common return air duct means connecting the ventilation zones to the central station, each zone having branch supply duct means connected to the common supply air duct means and branch return duct means connected to the common return air duct means, and the central station including central supply fan means, central exhaust/return fan means and main damper means for controlling flow of fresh air into the common supply air duct means and recycling of return air from the common return air duct means to the common supply air duct means, the improvement comprising partition means for dividing the common return air duct means lengthwise into a main return air duct section and an auxiliary return air duct section, separate branch damper means for each zone for controlling communication of the branch return duct means of such zone with each of the return air duct sections, standby means for effecting isolation and exhaust of all return air from the auxiliary return air duct section, and control means including separate detection means for each zone operable upon the occurrence of fire conditions therein for actuating the standby means and the corresponding one of said separate damper means for directing all of the return air from any fire zone to exhaust through the auxiliary return air duct section and for directing all of the return air from any non-fire zone into the main return air duct section.
Claim 2
Dependent Claim
266 words
In a multi-zone building having a ventilation system that includes a central station serving a plurality of ventilation zones, common supply air duct means connecting the central station to the ventilation zones, common return air duct means connecting the ventilation zones to the central station, each zone having branch supply duct means connected to the common supply air duct means and branch return duct means connected to the common return air duct means, and the central station including central supply fan means, central exhaust/return fan means and main damper means for controlling flow of fresh air into the common supply air duct means and recycling of return air from the common return air duct means to the common supply air duct means, the improvement comprising partition means for dividing the common return air duct means lengthwise into a main return air duct section and an auxiliary return air duct section, separate branch damper means for each zone for controlling communication of the branch return duct means of such zone with each of the return air duct sections, standby means for effecting isolation and exhaust of all return air from the auxiliary return air duct section, and control means including separate detection means for each zone operable upon the occurrence of fire conditions therein for actuating the standby means and the corresponding one of said separate damper means for directing all of the return air from any fire zone to exhaust through the auxiliary return air duct section and for directing all of the return air from any non-fire zone into the main return air duct section.
Claim 3
Dependent Claim
78 words
An arrangement as defined in claim 1 wherein said standby means includes standby exhaust means having a standby damper controlling communication of the auxiliary return air duct section to exterior atmosphere, and auxiliary damper means for isolating the auxiliary return air duct section from the main supply air duct means and the main return air duct section to direct the return air in the auxiliary return air duct section to the standby exhaust means in the fire mode.
Claim 4
Dependent Claim
152 words
An arrangement as defined in claim 2 wherein the control means is automatically responsive to any of the separate detection means upon the occurrence of fire conditions in the corresponding zone for operating the auxiliary damper means to close and isolate the auxiliary return air duct section from the central exhaust/return fan means for actuating the standby exhaust means and standby damper means, for positioning the branch damper means for any fire zone so that all return air from any fire zone is directed through the auxiliary return air duct section until the corresponding fire detection means returns to normal, for positioning the branch damper means for any non-fire zone so that all return air for any non-fire zone is directed through the main return air duct section when the corresponding fire detection means are normal and for returning all equipment to normal mode when all fire detection means return to normal.
Claim 5
Dependent Claim
92 words
An arrangement as defined in claim 1 where said standby means includes variable volume standby exhaust means to operate at a capacity that depressurizes any fire zones and having a standby damper normally preventing communication of the auxiliary return air duct section with exterior atmosphere, and auxiliary damper means for isolating the auxiliary return air duct section from the main supply air duct means and the main return air duct section to direct the return air in the auxiliary return air duct section to the standby exhaust means in the fire mode.
Claim 6
Dependent Claim
41 words
An arrangement as defined in claim 4 and including static pressure controller means responsive to pressure in the ventilation system to control the capacity of the variable volume stand-by exhaust means to effect the desired pressure reduction in the fire zones.
Claim 7
Dependent Claim
37 words
An arrangement as defined in claim 1 wherein said control means is connected to actuate said main damper means to control delivery of as much as 100 percent fresh air to the ventilation zones during fire mode.
Claim 8
Dependent Claim
57 words
An arrangement as defined in claim 1 wherein said common supply air duct means includes air reheat means and said control means is connected to actuate said main damper means and said air reheat means to control delivery of as much as 100 percent fresh air to the ventilation zones during fire mode regardless of exterior temperature.
Claim 9
Dependent Claim
44 words
An arrangement as defined in claim 1 and including variable volume sprinkler means disposed in the auxiliary return air duct section and having a sprinkler head and temperature detector for each zone and operable for automatically controlling return air temperature from any fire zone.
Claim 10
Dependent Claim
63 words
An arrangement as defined in claim 1 wherein each of said separate damper means comprises a dual damper having a normal mode position to direct return air from the corresponding zone into both return air duct sections and having a fire mode position to direct all return air into the auxiliary return air duct section when the corresponding zone is a fire zone.
Claim 11
Dependent Claim
195 words
An arrangement as defined in claim 1 wherein the ventilation zones comprise separate floors of a multi-story building, the common supply air and return air duct means and the partition means are vertical and the branch supply and return duct means are horizontal and the central supply fan means, the central exhaust/return fan means and the main damper means are located at the top of the common supply air and return air duct means and wherein said standby means includes standby exhaust means to operate at a capacity that depressurizes any fire zones and having a connection to the auxiliary return air duct section at a location beneath the central exhaust/return fan means and having a standby damper for controlling communication of the auxiliary return air duct section to exterior atmosphere, and auxiliary damper means mounted in the auxiliary return air duct section between the said connection and the central exhaust/return fan means for isolating the return air duct section from the main supply air duct means and the main return air duct section to direct the return air in the auxiliary return air duct section to the standby exhaust means in the fire mode.
Claim 12
Independent Claim
131 words
A method of fire control and ventilation for multi-zone buildings comprising: drawing fresh air into the building to form a main supply air stream; subdividing the main stream into branch streams each leading into a separate zone; drawing return air from the zones to form a main return air stream and an auxiliary return air stream; normally exhausting some of the air from the return air streams while recycling the remainder into the main supply air stream; and isolating the return air streams in response to fire conditions occurring in any zone by exhausting all of the auxiliary return air stream while directing all return air from any fire zone into the auxiliary return air stream and directing all return air from any non-fire zone into the main return air stream.
Claim 13
Independent Claim
131 words
A method of fire control and ventilation for multi-zone buildings comprising: drawing fresh air into the building to form a main supply air stream; subdividing the main stream into branch streams each leading into a separate zone; drawing return air from the zones to form a main return air stream and an auxiliary return air stream; normally exhausting some of the air from the return air streams while recycling the remainder into the main supply air stream; and isolating the return air streams in response to fire conditions occurring in any zone by exhausting all of the auxiliary return air stream while directing all return air from any fire zone into the auxiliary return air stream and directing all return air from any non-fire zone into the main return air stream.
Claim 14
Dependent Claim
39 words
A method in accordance with claim 11 wherein exhaust of all of tHe auxiliary return air stream in response to fire conditions is effected at a rate to produce a multifold increase in return air from any fire zone.
Claim 15
Dependent Claim
54 words
A method in accordance with claim 11 and including the step of sensing the pressure in the ventilation system during fire conditions and controlling the exhaust of the auxiliary return air stream in accordance with the pressure in the system to effect a pressure reduction in any fire zone relative to any non-fire zone.
Claim 16
Dependent Claim
37 words
A method in accordance with claim 11 and including supplying 100 percent fresh air to all zones during the existence of fire conditions while effecting a pressure reduction in any fire zone relative to any non-fire zone.
References Cited (Backward Citations)
US3570384A
Cited
US3739707A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |