GB2208427A - Smoke diverter valve in air duct - Google Patents

Smoke diverter valve in air duct Download PDF

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Publication number
GB2208427A
GB2208427A GB8718342A GB8718342A GB2208427A GB 2208427 A GB2208427 A GB 2208427A GB 8718342 A GB8718342 A GB 8718342A GB 8718342 A GB8718342 A GB 8718342A GB 2208427 A GB2208427 A GB 2208427A
Authority
GB
United Kingdom
Prior art keywords
duct
flap
outlet
seating
unit according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB8718342A
Other versions
GB2208427B (en
GB8718342D0 (en
Inventor
Peter John Thwaites
Peter Waterworth Joyce
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dufaylite Developments Ltd
Original Assignee
Dufaylite Developments Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dufaylite Developments Ltd filed Critical Dufaylite Developments Ltd
Priority to GB8718342A priority Critical patent/GB2208427B/en
Publication of GB8718342D0 publication Critical patent/GB8718342D0/en
Publication of GB2208427A publication Critical patent/GB2208427A/en
Application granted granted Critical
Publication of GB2208427B publication Critical patent/GB2208427B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62C—FIRE-FIGHTING
    • A62C2/00—Fire prevention or containment
    • A62C2/06—Physical fire-barriers
    • A62C2/12—Hinged dampers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K11/00—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves
    • F16K11/02—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit
    • F16K11/04—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only lift valves
    • F16K11/052—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only lift valves with pivoted closure members, e.g. butterfly valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/08—Air-flow control members, e.g. louvres, grilles, flaps or guide plates
    • F24F13/10—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers
    • F24F13/14—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre
    • F24F13/1406—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre characterised by sealing means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
    • F24F11/32—Responding to malfunctions or emergencies
    • F24F11/33—Responding to malfunctions or emergencies to fire, excessive heat or smoke
    • F24F11/34—Responding to malfunctions or emergencies to fire, excessive heat or smoke by opening air passages
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
    • F24F11/32—Responding to malfunctions or emergencies
    • F24F11/33—Responding to malfunctions or emergencies to fire, excessive heat or smoke
    • F24F11/35—Responding to malfunctions or emergencies to fire, excessive heat or smoke by closing air passages
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/08—Air-flow control members, e.g. louvres, grilles, flaps or guide plates
    • F24F13/10—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers
    • F24F13/14—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre
    • F24F13/1426—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre characterised by actuating means
    • F24F2013/148—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre characterised by actuating means with magnets

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Air-Flow Control Members (AREA)

Abstract

A duct unit for use in air conditioning installations has one inlet (1) and two outlets (2, 3). A flap (7) is swingably mounted for rotation between the two outlets and can be swung from a position in which it closes one of them to a position (7') in which it closes the other and vice versa. Gasketed seatings provide that, in either closure position, there is a proper seal so that the unit may act to prevent the spread of fire. Preferably the unit includes a latch (24-26) adapted to hold the flap tightly sealed in one of its two positions. The valve flap may be spring biassed into the latched position and held against the bias by an electromagnet 23. The flap has an external handle for manual resetting. <IMAGE>

Description

SMOKE DIVERTER UNITS This invention relates to smoke diverter units, and in particular to units which may be installed as part of the air conditioning ducting within a building.
British Patent Specifications 2103483, 2107982 and 2138934 are all concerned with air conditioning systems in buildings. A problem with air conditioning systems in buildings is that they move air from part of the building to another, and if a fire breaks out they can promote the spread of fire and products of combustion from one part of a building to another. In order to design safe systems it is accordingly important to have ways of preventing the spread of fire through air conditioning systems should a fire break out.
The specifications referred to above are related to this problem, and each discloses in broad general terms a mechanism for forming part of a ducting installation including a three way duct piece. This is illustrated diagrammatically in Figures 3 and 4 of specification 2103483 and Figures 5 and 6 of specification 2107982. The duct piece there illustrated has three ports, which in use are arranged as one inlet port and two outlet ports.
Within the section is a swingable flap which is arranged to close one or other outlet port. In use, air normally flows through the duct from inlet to the normally open outlet port, e.g. into the next section of a building.
Should a fire break out, the swingable flap is arranged to move to close one outlet port and open the other, e.g.
enabling smoke and flames to be diverted, e.g. to atmosphere.
The specifications as referred to above give no constructional details as to how such apparatus is to be constructed and we have found that a simple hinged flap is inadequate.
According to the present invention there is provided a duct unit for use in air conditioning and like installations including an elongate duct section defined by sidewalls and having an inlet at one end and a first outlet at its other end, one side wall in the duct section including a second outlet, and a flap swingably mounted for rotation about an axis located between the first and second outlet, and swingable from a position in which it closes the first outlet to a position in which it closes the second outlet and vice versa, wherein around the first outlet and around the walls of the duct are arranged two seatings, each of which can co-operate with the flap, where the edges of the flap are provided with gasketing material adapted to seal the flap against one of the seatings in either position, wherein means are provided to hold the flap normally against the seating around the second outlet to close the same and wherein latch means are provided to hold the flap securely latched against the seating around the walls of the duct when sealing the first outlet.
Preferably the flap is spring biased towards the seating around the walls of the duct.
Conveniently the flap is hinged by means of a hinge pin set adjacent the same wall of the duct as the second outlet, and preferably the hinge pin is provided with a gasket seal thereagainst.
Conveniently the cross-section of the duct and of each outlet is rectangular, and the flap is in the form of a rectangular tray hinged one side and having gasket material at its edges and projecting slightly to both sides of the tray, which gasket material is adapted to abut and seal against the seating about the second outlet or the seating which goes around the walls of the duct.
The means for holding the flap normally against the seating surrounding the second outlet is preferably a solenoid. This is arranged in practice to operate in a fail-safe manner i.e. the solenoid is energized normally and holds the flap in the desired position by magnetic attraction. If a fire breaks out or smoke is detected, the electrical supply to the solenoid is interrupted, thus releasing the flap. The flap also releases if there is any other interruption in the supply to the solenoid for any other reason. The device thus "fails safe" diverting air in the duct e.g. to atmosphere should anything happen to the system.
Preferably the wall of the duct opposite the side of the outlet has in it, adjacent part of the seating for the flap extending across the duct, spring latch means which act to latch the flap in position if it is moved to seat against the seating extending across the duct.
Preferably the latch means can be released by an appropriate lever, key or the like from outside the duct.
Preferably also the position of the flap can then be moved, again from outside the duct. Most conveniently, the hinge pin of the flap is connected to a lever arm which can be moved manually. The lever arm is conveniently located in a housing located on one wall of the duct, and the flap may be spring biased by an appropriate spring attached to that lever arm and fixed appropriately internally of that housing.
The invention is illustrated by way of example with reference to the accompanying drawings in which Figure 1 is a diagrammatic axial section through a diverted unit in accordance with the present invention, Figure 2 is a cross-section through the flap member of the unit of Figure 1, and Figure 3 is a side view of the unit showing the flap actuation lever.
Referring to the drawings a duct section has an inlet 1 and outlet 2 and a second outlet 3. The duct is of rectangular cross-section and the second outlet 3 is likewise rectangular. As shown, the second outlet is in the upper horizontal wall or ceiling of the duct though itwill be appreciated that it could be in a side wall or in the base of the duct.
Above the second outlet is a similar rectangular section short length of duct with an end flange for connection to a like flange on further ducting if desired.
Set on a hinge pin 6 adjacent the ceiling of the duct is a swingable flap 7 of generally tray like construction. This consists, as is best seen in Figure 2, of a steel central tray 10 having upstanding edges 11.
Attached round three of its edges is a folded ribbon of ceramic fibre heat insulating tape 12. It is attached to flange 11 by means of rivets 13 which pass through the tape 12 and are secured at their other ends to an external steel strip 14. As clearly evident from Figure 2, the folded ceramic fibre tape 12 is wider than strips 14 or the height of walls 11 and the tape is so arranged that, as shown in Figure 2, the upper edges of the folded ribbon is above the metalwork of the tray and the lower edge is below the metalwork of the tray.
This arrangement enables the tray to seat and seal securely against either of two seatings. The first is formed by the three portions of the ceiling of the duct which surround outlet 3. The second is formed by a seating constituted by three steel bars, one set on the base of the duct and denoted 20 in the drawing and the others set on the sides and denoted 21.
Set at one edge of the tray 7 is a magnetically soft armature 22. This is designed to cooperate with a solenoid 23 mounted just inside the second outlet 3.
Protruding through the floor of the duct are the jaws 24 of two sprung catches 25 located spaced apart from one another. As shown in Figure 1, the catches are pivoted about an axis 26 and are biased in the clockwise direction by a spring (not shown) to the position shown in Figure 1. A housing 28 surrounds the catch mechanism on the exterior of the floor of the duct.
Hinge pin 6 to which the flap 7 is attached is mounted closely adjacent the ceiling of the duct. A ceramic fibre tape is held compressed against the hinge pin by a bar 30 extending across the ceiling of the duct.
As shown in Figure 3, attached to the end of hinge pin 6 is a lever 40 which is located in a housing 42 mounted on the side of the duct. The cover of the housing is omitted for clarity but a normal sheet steel lockable cover to be provided. Lever 40 is biased in an anti-clockwise direction by means of a tension spring 43 which is fixed between a fixed point 45 such as stud welded to the side of the duct and engages in one of a number of holes 44 located in lever 40. Varying the hole into which spring 43 is fitted varies the spring bias on the flap 7.
When the device is used in the orientation shown in the drawings, relatively light spring bias is needed on spring 43, since the flap will tend to move to the position shown in full in Figure 1 under the effect of gravity. If the item is installed in some other orientation, greater leverage and greater spring bias is secured by engaging spring 43 with a hole 44 more remote from hinge pin .6.
In normal conditions air is passed from inlet 1 throughout outlet 2 with the flap 7 being in the position shown in dotted lines and indicated in 7 in Figure 1. It is held in that position by armature 22 being held by the electro-magnet 23.
If there is a fire or if for some other reason there is a system problem, the current to the electro-magnet ceases, and the flap 7 drops assisted by the spring bias into the position shown in Figure 1. The configuration of the teeth 24 and the edge of flap 7 cooperate to depress teeth 24 as the flap comes into the position shown in Figure 1, with the spring latches 25 catching over the edge of the flap 7 as the flap impacts on the frame formed of bars 20 and 21.
Prior to such movement, the outlet 3 was sealed by the pressure of one edge of refractory fibre ribbon 12 against the ceiling of the duct. In the position shown in Figure 1, the main outlet 2 of the duct is sealed off by engagement of the other edges of the ribbon 12 against bars 20 and 21.
Ribbon 12 is preferably a highly refratory ceramic ribbon material of the type used for gasketing in high temperature applications. A particularly valuable material is ceramic fibre tape sold under the registered trade mark Fiberfrax by the Carborundum Company Limited.
Such materials are available as tapes 2.5 mm thick and 76 mm wide and a folded tape may be used to provide the gasket. Such tapes are resistant up to 12600C, continuous exposure, so even if very hot combustion products pass along the ductwork, through inlet 1 and out through outlet 3, the integrity of the seal is maintained and hot combustion products do not pass from outlet 2.

Claims (10)

1. A duct unit for use in air conditioning and like installations including an elongate duct section defined by sidewalls and having an inlet at one end and a first outlet at its other end, one side wall in the duct section including a second outlet, and a flap swingably mounted for rotation about an axis located between the first and second outlet, and swingable from a position in which it closes the first outlet to a position in which it closes the second outlet and vice versa, wherein around the first outlet and around the walls of the duct are arranged two seatings, each of which can co-operate with the flap, where the edges of the flap are provided with gasketing material adapted to seal the flap against one of the seatings in either position, wherein means are provided to hold the flap normally against the seating around the second outlet to close the same and wherein latch means are provided to hold the flap securely latched against the seating around the walls of the duct when sealing the first outlet.
2. A duct unit according to Claim 1, wherein the flap is spring biased towards the seating around the walls of the duct.
3. A duct unit according to Claim 1 or 2, wherein the flap is hinged by means of a hinge pin set adjacent the same wall of the duct as the second outlet.
4. A duct unit according to Claim 3, and including a gasket seal against the hinge pin.
5. A duct unit according to Claim 3 or 4, and including a lever arm attached to the hinge pin and located in a housing located on one wall of the duct.
6. A duct unit according to any one of Claims 1 to 5, wherein the cross-section of the duct and of each outlet is rectangular and the flap is in the form of a rectangular tray hinged one side and having gasket material at its edges and projecting slightly to both sides of the tray, which gasket material is adapted to abut and seal against the seating about the second outlet or the seating which goes around the walls of the duct.
7. A duct unit according to any one of Claims 1 to 6, wherein the means for holding the flap normally against the seating surrounding the second outlet is a solenoid.
8. A duct unit according to any one of Claims 1 to 7, wherein the wall of the duct opposite the side of the outlet has in it, adjacent part of the seating for the flap extending across the duct, spring latch means which act to latch the flap in position if it is moved to seat against the seating extending across the duct.
9. A duct unit according to Claim 8, and including means accessible from outside the duct to release the latch.
10. A duct unit substantially as hereinbefore described with reference to the accompanying drawings.
GB8718342A 1987-08-03 1987-08-03 Smoke diverter units Expired - Fee Related GB2208427B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB8718342A GB2208427B (en) 1987-08-03 1987-08-03 Smoke diverter units

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB8718342A GB2208427B (en) 1987-08-03 1987-08-03 Smoke diverter units

Publications (3)

Publication Number Publication Date
GB8718342D0 GB8718342D0 (en) 1987-09-09
GB2208427A true GB2208427A (en) 1989-03-30
GB2208427B GB2208427B (en) 1991-07-10

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Family Applications (1)

Application Number Title Priority Date Filing Date
GB8718342A Expired - Fee Related GB2208427B (en) 1987-08-03 1987-08-03 Smoke diverter units

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GB (1) GB2208427B (en)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2235761A (en) * 1989-08-23 1991-03-13 Glidevale Building Prod Building ventilator
EP0533282A1 (en) * 1991-09-18 1993-03-24 Philip Rijk Koudijs A discharge system for combustion gases
GB2341921A (en) * 1998-09-22 2000-03-29 Daimler Chrysler Ag Ventilation element
EP1170534A2 (en) * 2000-06-27 2002-01-09 Siemens Automotive Inc. Fuel cell control valves
EP1245915A1 (en) * 2001-03-30 2002-10-02 Sankyo Seiki Mfg. Co. Ltd. Refrigerator damper apparatus and refrigerator
US6830060B2 (en) 2000-06-27 2004-12-14 Siemens Vdo Automotive, Inc. Air mass flow controller valve
EP1688164A1 (en) * 2005-02-02 2006-08-09 Dieter Betz Fire damper for flow passages
CN102425686A (en) * 2011-10-11 2012-04-25 无锡市华通电力设备有限公司 Bypass reversing baffle plate for waste heat boiler
DE102011108182A1 (en) * 2011-07-22 2013-01-24 Schulte & Todt Systemtechnik Gmbh & Co.Kg Component used in device for closing pipe line e.g. ventilation duct in fire case, has shut-off unit is transferred from opening to partial closing position of pipe line and is arranged to close lower opening in installation position
DE202011109667U1 (en) 2011-12-30 2013-04-16 Gert Bartholomäus Fire damper with branch
CN103148302A (en) * 2013-03-22 2013-06-12 苏州富士电梯有限公司 Air guide pipe structure for alternatively switching straight and lateral air blows of lift car ceiling
CN107606233A (en) * 2017-11-03 2018-01-19 山东佩森环保科技股份有限公司 A kind of high-temperature flue gas triple valve
EP3343077A1 (en) * 2016-12-28 2018-07-04 Nederman Holding AB Back pressure flap valve arrangement and the use thereof

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2235761A (en) * 1989-08-23 1991-03-13 Glidevale Building Prod Building ventilator
GB2235761B (en) * 1989-08-23 1993-03-31 Glidevale Building Prod Building ventilator
EP0533282A1 (en) * 1991-09-18 1993-03-24 Philip Rijk Koudijs A discharge system for combustion gases
US5322087A (en) * 1991-09-18 1994-06-21 Koudijs Philip R Discharge system for combustion gases
GB2341921A (en) * 1998-09-22 2000-03-29 Daimler Chrysler Ag Ventilation element
GB2341921B (en) * 1998-09-22 2000-08-23 Daimler Chrysler Ag Ventilation element
US6244952B1 (en) 1998-09-22 2001-06-12 Daimlerchrysler Ag Ventilation assembly for a passenger vehicle
EP1170534A3 (en) * 2000-06-27 2004-01-02 Siemens Automotive Inc. Fuel cell control valves
EP1170534A2 (en) * 2000-06-27 2002-01-09 Siemens Automotive Inc. Fuel cell control valves
US6830060B2 (en) 2000-06-27 2004-12-14 Siemens Vdo Automotive, Inc. Air mass flow controller valve
EP1245915A1 (en) * 2001-03-30 2002-10-02 Sankyo Seiki Mfg. Co. Ltd. Refrigerator damper apparatus and refrigerator
US6647740B2 (en) 2001-03-30 2003-11-18 Sankyo Seiki Mfg. Co., Ltd. Refrigerator damper apparatus and refrigerator
EP1688164A1 (en) * 2005-02-02 2006-08-09 Dieter Betz Fire damper for flow passages
DE102011108182A1 (en) * 2011-07-22 2013-01-24 Schulte & Todt Systemtechnik Gmbh & Co.Kg Component used in device for closing pipe line e.g. ventilation duct in fire case, has shut-off unit is transferred from opening to partial closing position of pipe line and is arranged to close lower opening in installation position
DE102011108182B4 (en) 2011-07-22 2018-05-03 Günter Schulte Device for closing a pipeline, in particular a ventilation duct, in case of fire
CN102425686A (en) * 2011-10-11 2012-04-25 无锡市华通电力设备有限公司 Bypass reversing baffle plate for waste heat boiler
CN102425686B (en) * 2011-10-11 2013-03-13 无锡市华通电力设备有限公司 Bypass reversing baffle plate for waste heat boiler
DE202011109667U1 (en) 2011-12-30 2013-04-16 Gert Bartholomäus Fire damper with branch
CN103148302A (en) * 2013-03-22 2013-06-12 苏州富士电梯有限公司 Air guide pipe structure for alternatively switching straight and lateral air blows of lift car ceiling
EP3343077A1 (en) * 2016-12-28 2018-07-04 Nederman Holding AB Back pressure flap valve arrangement and the use thereof
US10315059B2 (en) 2016-12-28 2019-06-11 Nederman Holding Ab Back pressure flap valve arrangement and the use thereof
CN107606233A (en) * 2017-11-03 2018-01-19 山东佩森环保科技股份有限公司 A kind of high-temperature flue gas triple valve

Also Published As

Publication number Publication date
GB2208427B (en) 1991-07-10
GB8718342D0 (en) 1987-09-09

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