GB2330772A - Ventilation duct shutter - Google Patents
Ventilation duct shutter Download PDFInfo
- Publication number
- GB2330772A GB2330772A GB9823551A GB9823551A GB2330772A GB 2330772 A GB2330772 A GB 2330772A GB 9823551 A GB9823551 A GB 9823551A GB 9823551 A GB9823551 A GB 9823551A GB 2330772 A GB2330772 A GB 2330772A
- Authority
- GB
- United Kingdom
- Prior art keywords
- flaps
- axis
- insertion tube
- fire
- fact
- 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
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
- A62C2/14—Hinged dampers with two or more blades
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62C—FIRE-FIGHTING
- A62C2/00—Fire prevention or containment
- A62C2/06—Physical fire-barriers
- A62C2/065—Physical fire-barriers having as the main closure device materials, whose characteristics undergo an irreversible change under high temperatures, e.g. intumescent
-
- 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
- F24F13/1413—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre using more than one tilting member, e.g. with several pivoting blades
-
- 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
- F24F2013/146—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 springs
Abstract
A fire shutter 1 for a ventilation duct 2 has an insertion tube 3 with an inwardly-directed rim 4 at one end, two flaps 6, 7 in the form of wings pivotally mounted on a rod 5 extending perpendicularly to the axis X of the tube 3, and means 14 including a fusible element and serving to retain the flaps 6, 7 parallel to the axis X in the open position against two springs 17, 18. If the fusible element melts, the springs deploy the flaps into a closure plane. The flaps 6, 7 include an overlap region 10, 11 in the middle thereof. The springs press against regions close to the peripheries of the flaps.
Description
1 2330772 A FIRE-BRAKE SHUTTER FOR A VENTILATION DUCT
17he present invention relates to the field of firebrake or flame-brake devices provided in air flow installations.
More particularly, the invention relates to a firebrake shutter designed to be installed in a ventilation duct and comprising:
an insertion tube of axis X which fits in said duct; two wing-shaped flaps pivotally mounted on a rod carried by the insertion tube and defining an axis of rotation Y perpendicular to the axis X and parallel to central rims of said two flaps, the two flaps being suitable for taking up an open position in which they are is held in planes parallel to the axis X and to the axis of rotation Y, and a closed position in which they are deployed into a plane perpendicular to the axis X, thereby closing the insertion tube; 0 holding means for holding the two flaps in the open position, said holding means including a fusible element suitable for melting at a determined temperature to release said holding elements; a resilient means pressing against the flaps and designed to urge the flaps towards the closed position when the fusible element melts; and 6 an abutment wall provided inside the tube and against which the peripheral rims of the flaps press when in the closed position.
Such shutters are installed, in particular, in ventilation ducts that pass through walls. Their function is to isolate premises in the event of a fire so as to prevent the fire propagating to adjacent premises. When gas leaving the premises where there is a fire via such ducts reaches a predetermined temperature, the fusible element melts and the flaps deploy under drive from the resilient elements and they close the insertion tube. In general, the flaps are covered in insulating 2 materials that withstand heat, thereby enabling the firebrake device to perform its function of isolating premises safely for a certain length of time, until the emergency services have taken action.
In general, ventilation ducts in a building are connected to a suction device. If there is a fire in one of the premises, its fire-brake shutter must isolate the premises effectively so as to comply with present safety standards. When the flaps are in the closed position, sealing must be perfect between the abutment wall and the peripheral rims of the flaps, and also between the central rims of the flaps, which in most presently-known devices are juxtaposed when the flaps are in the closed position. Present standards require this sealing to be is guaranteed for a certain length of time even if the suction generated by the suction device is as great as 150 Pascals.
The object of the invention is to provide improvements to fire-brake shutters that enable those safety criteria to be met.
The invention achieves its object by the following set of dispositions:
the resilient means comprise at least two coil springs surrounding said rod and having end branches permanently pressing against the flaps in regions remote from the rod; the abutment wall is constituted by an annular rim provided at one end of the insertion tube and which extends perpendicularly to the axis X towards the inside of said tube; and adjacent to its rectilinear edge, one of the flaps has an overlap region which covers a portion of the second flap when in the closed position.
The invention also proposes improving sealing in the annular space between the insertion tube and the inside wall of the ventilation duct.
3 To this end, the insertion tube includes sealing means suitable for cooperating with the ventilation duct.
Advantageously, the sealing means include at least one annular ring of intumescent material surrounding the insertion tube and secured thereto.
The sealing means may also comprise at least one elastomer ring, and preferably two elastomer rings.
Other advantages and characteristics of the invention appear on reading the following description given by way of example and made with reference to the accompanying drawings, in which:
a Figure 1 is a face view of the fire-brake shutter of the invention with its flaps in their open position; is 0 Figure 2 is a section on line II-II of Figure 1; 0 Figure 3 is a section in an axial plane perpendicular to the pivot axis of the flaps and showing the flaps in the open position; and 0 Figure 4 is similar to Figure 3 but showing the flaps in the closed position.
The drawings show a fire-brake shutter 1 of axis X that is designed to be inserted into a tubular duct 2 in a ventilation circuit, likewise of axis X.
The shutter 1 comprises an insertion tube 3 having, at one end, an annular rim 4 extending perpendicularly to the axis X towards the inside of the tube 3. A rod 5, extending perpendicularly to the axis X, is mounted in the insertion tube 3. The center of the rod 5 intersects the axis X.
Two flaps 6 and 7 in the form of semicircular wings are pivotally mounted on the rod 5 by means of tabs 8a and 8b for the flap 6 and tabs 9a and 9b for the flap 7. The rod 5 defines a pivot axis Y for the flaps 6 and 7. The tabs 8a & 8b and 9a & 9b extend perpendicularly to the planes of the flaps 6 and 7 and are disposed in the vicinity of respective middle rectilinear rims 10 and 11 of the flaps 6 and 7. The rod 5 passes through orifices 4 J formed in the tabs 8a, 8b, 9a, and 9b, and is parallel to the planes of the flaps 6 and 7.
The faces of the two flaps 6 and 7 are covered in layers 12 and 13 of insulating material that withstands fire.
The two flaps 6 and 7 can take up two extreme positions. In the normal operating position, which is the open position for the shutter 1, the two flaps are folded into planes that are parallel to the axes X and Y so as to allow ambient air to flow freely through the insertion tube 3.
In the closed position, the two flaps 6 and 7 are deployed in a plane P1 perpendicular to the axis X and adjacent to the plane of the rim 4 so that the periphery of the flaps 6 and 7 bears against the inside face of the rim 4, thereby providing sealing at the rim.
The flaps 6 and 7 are held in the open position by conventional holding means 14 which include, in particular, a fusible element that is designed to melt at a determined temperature so as to release the holding means 14. The holding means can be fixed on hooks 16a and 16b fitted to the flaps 6 and 7. Two spaced-apart coil springs 17 and 18 with their turns surrounding the rod 5 have respective end branches 25 19a & 19b and 20a & 20b which press against the inside faces of the flaps 6 and 7 close to the peripheries of said flaps in zones that are remote from the rod 5. In the open position, the holding means 14 retain the flaps 6 and 7 against the forces exerted by the end branches of the springs 17 and 18. In the event of the fusible element of the holding means 14 melting, the end branches 19a & 19b and 20a & 20b cause the flaps 6 and 7 to deploy into the plane P1, and they continue to exert positive force on the peripheries of the flaps 6 and 7 in the closed position.
To this end, the positions of the bearing points where the end branches 19a & 19b and 20a & 20b of the two is coil springs press against the inside faces of the flaps 6 and 7 are preferably uniformly distributed over the peripheries of the flaps 6 and 7 about the rod 5. These bearing points are remote from the rod 5 and close to the peripheries of the flaps 6 and 7, and they are at a distance from the midplane perpendicular to the axis Y of the rod 5. The distance between two branches disposed on the same flap i.e. 19a & 20a or 19b & 20b is substantially equal to or slightly less than the radius of the insertion tube 3. It has been observed that the presence of two coil springs disposed as described above considerably improves sealing after the shutter has been exposed to heat due to a fire, compared with conventional shutters that have a single spring only exerting forces in the middle regions of the flaps.
As can be seen in Figures 3 and 4, the two flaps 6 and 7 are not identical. The middle rim 10 of the flap 6 extends further than the middle rim 11 of the flap 7, such that the middle rim 10 which is connected to the remainder of the flap 6 by a pair of bends overlies the middle rim 10 of the flap 7 when the shutter is in the closed position as shown in Figure 4.
By means of this disposition and because the springs 17 and 18 act in regions that are remote from the rod 5, when the shutter is in its closed position, sealing is provided against hat gases both around the periphery of the flaps 6 and 7 and also in the middle region thereof. It should be observed that the faces of the flaps 6 and 7 which bear against the rim 4 are generally their faces that look towards the premises against which protection is to be provided. The force of the springs 18 and 19 and the positions of their bearing points against the inside faces of the flaps 6 and 7 make it possible to guarantee that the shutter provides perfect sealing, even if the suction downstream is 150 Pascals.
Sealing between the insertion tube 3 and the duct 2 is preferably provided by means of three sealing rings 6 disposed in succession around the outside of the insertion tube. The ring 21, made of intumescent material, which is fixed to the insertion tube 3 can withstand temperatures in excess of 10000C and at 1250C it reacts by swelling. The second sealing ring 22 is an elastomer 0-ring which provides sealing in the temperature range 1200C to 8000C. The third ring 23 is an elastomer gasket which includes one or more lips and which provides cold sealing up to temperatures which may lie in the range 1200C to 1500C.
7 1:Z
Claims (1)
- CLAIMS 1/ A fire-brake shutter designed to be installed in a ventilationduct (2) and comprising:an insertion tube (3) of axis X which fits in said duct (2); 0 two wing-shaped flaps pivotally mounted on a rod (5) carried by the insertion tube (3) and defining an axis of rotation Y perpendicular to the axis X and parallel to central rims (10, 11) of said two flaps (6, 7), the two flaps (6, 7) being suitable for taking up an open position in which they are held in planes parallel to the axis X and to the axis of rotation Y, and a closed position in which they are deployed into a plane (P1) perpendicular to the axis X, thereby closing the insertion tube (3); 0 holding means (14) for holding the two flaps in the open position, said holding means including a fusible element suitable for melting at a determined temperature to release said holding elements; 0 resilient means (18, 19) pressing against the flaps (6, 7) and designed to urge the flaps towards the closed position when the fusible element melts; and an abutment wall (4) provided inside the tube (3) and against which the peripheral rims of the flaps press when in the closed position, the shutter being characterized by the fact that:0 the resilient means comprise at least two coil springs (18, 19) surrounding said rod (5) and having end branches (19a & 19b, 20a & 20b) permanently pressing against the flaps (6, 7) in regions remote from the rod (5); 0 the abutment wall (4) is constituted by an annular rim provided at one end of the insertion tube (3) and which extends perpendicularly to the axis X towards the inside of said tube; and 8 0 adjacent to its rectilinear edge, one of the flaps (6) has an overlap region (10) which covers a portion (11) of the second flap (7) when in the closed position.2/ A fire-brake shutter according to claim 1, characterized by the fact that the insertion tube (3) also includes sealing means suitable for cooperating with the ventilation duct.3/ A fire-brake shutter according to claim 2, characterized by the fact that the sealing means include at least one annular ring (21) of intumescent material surrounding the insertion tube (3) and secured thereto.4/ A fire-brake shutter according to claim 2, characterized by the fact that the sealing means comprise at least one elastomer ring (22, 23).S/ A fire-brake shutter according to claim 4, characterized by the fact that the sealing means comprise at least two elastomer rings (22, 23).6/ A shutter according to claim 4 or 5, characterized by the fact that the sealing means further comprise an annular ring (21) of intumescent material surrounding the insertion tube (3) and secured thereto.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR9713619A FR2770411B1 (en) | 1997-10-30 | 1997-10-30 | FIREPROOF VALVE FOR AERATION DUCT |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB9823551D0 GB9823551D0 (en) | 1998-12-23 |
| GB2330772A true GB2330772A (en) | 1999-05-05 |
| GB2330772B GB2330772B (en) | 2001-06-06 |
Family
ID=9512830
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9823551A Expired - Fee Related GB2330772B (en) | 1997-10-30 | 1998-10-29 | A fire-brake shutter for a ventilation duct |
Country Status (3)
| Country | Link |
|---|---|
| DE (1) | DE19849863B4 (en) |
| FR (1) | FR2770411B1 (en) |
| GB (1) | GB2330772B (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2350295A (en) * | 1999-03-31 | 2000-11-29 | Flaekt Oy | Fire damper for a duct |
| GB2369571A (en) * | 2000-12-01 | 2002-06-05 | Tri Air Innovations Ltd | Air flow controller and fire damper in an air flow duct |
| WO2004072531A1 (en) * | 2003-02-11 | 2004-08-26 | Truss Holdings Pty. Ltd. | Damper with rotary valve |
| US6991536B2 (en) | 2000-12-01 | 2006-01-31 | Kent Tooling And Components Limited | Air flow controller and fire damper in an air flow duct |
| US7195032B2 (en) * | 2003-01-30 | 2007-03-27 | Beth-el Zikhron-Ya′Aqov Industries, Ltd | Unidirectional, adjustable flap valves |
| CN110114122A (en) * | 2017-08-28 | 2019-08-09 | 扎斯特瑞特制造有限责任公司 | Ventilation safety cabinet equipped with thermotropic fluctuation dampers |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19825407B4 (en) * | 1998-06-06 | 2005-09-15 | Eidmann, Jürgen | Fire isolation device |
| FR2794210B1 (en) * | 1999-05-28 | 2001-08-31 | Crouzet Automatismes | DEVICE FOR DETECTING THE SIMULTANEOUS CLOSURE OF TWO MOBILE ORGANS AND ITS APPLICATION TO A FLAP-STOP FIRE SYSTEM |
| AT410283B (en) * | 1999-11-02 | 2003-03-25 | Kamleithner Maly Uta Ing Mag | FIRE PROTECTION DEVICE |
| AT411965B (en) * | 1999-11-02 | 2004-08-26 | Kamleithner Maly Uta Ing Mag | Fire protection unit for vents and lines comprises housed protection unit with propagation toroid composed of laminate plate swelling to fill line section under heat. |
| WO2003038283A2 (en) | 2001-10-31 | 2003-05-08 | Alfred Eichelberger Gmbh & Co. Kg | Smoke protection for rooms |
| DE10204387A1 (en) * | 2001-12-04 | 2003-06-12 | Emil Siegwart | Flow rate regulator |
| DE202006004839U1 (en) * | 2006-03-15 | 2006-06-29 | Maico Elektroapparate-Fabrik Gmbh | Check valves device |
| NL2003680C2 (en) * | 2009-10-21 | 2011-04-26 | Vero Duco Nv | SELF-REGULATING VENTILATION DEVICE AND VALVE COMPOSITION THEREFOR. |
| DE202013100532U1 (en) * | 2013-02-05 | 2013-02-13 | D + H Mechatronic Aktiengesellschaft | vent cap |
| EP2778554A1 (en) * | 2013-03-11 | 2014-09-17 | TROX GmbH | Shutoff valve for use in a conduit of an air conditioning system or a mechanical smoke ventilation assembly |
| DE102014113210A1 (en) * | 2014-09-12 | 2016-03-17 | Naber Holding Gmbh & Co. Kg | Closure arrangement for an air duct and a corresponding building arrangement |
| DE202017103273U1 (en) | 2017-05-31 | 2017-06-28 | Strulik Gmbh | Feuerschutzabsperrvorrichtung |
| CN108506215A (en) * | 2017-09-25 | 2018-09-07 | 约克（无锡）空调冷冻设备有限公司 | Silencing means |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4467824A (en) * | 1981-06-13 | 1984-08-28 | Strulik Wilhelm P | Self-closing fire damper for duct |
| US4474167A (en) * | 1977-05-02 | 1984-10-02 | Mccabe Francis J | Latch for a butterfly damper |
| GB2230951A (en) * | 1989-04-14 | 1990-11-07 | Nailor Hart Ind Inc | Fusible link assembly |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2205819A5 (en) * | 1972-11-06 | 1974-05-31 | Boucq Andre | |
| DE2342531A1 (en) * | 1973-08-23 | 1975-02-27 | Hans Guenter Schmidt | Ventilator and air-conditioner shutoff and damper - with flaps forming jet-shaped flow area which can be effectively closed |
| FR2316513A1 (en) * | 1975-07-01 | 1977-01-28 | Blayez Paul | Fire protection valve for air conditioning duct - has flaps held open by fusible clip and closed by torsion spring |
| FR2661100B1 (en) * | 1990-04-20 | 1994-02-11 | Hamon | FLAME-RESISTANT AND FIRE-RESISTANT SYSTEM FOR AN ELEMENT SUCH AS A DOOR OR PANEL, AND DEVICE INCORPORATING THE SAME. |
| DE29507931U1 (en) * | 1995-05-13 | 1995-08-10 | Wildeboer Werner Dipl Ing | Shut-off element for a fire protection shut-off device |
-
1997
- 1997-10-30 FR FR9713619A patent/FR2770411B1/en not_active Expired - Fee Related
-
1998
- 1998-10-29 GB GB9823551A patent/GB2330772B/en not_active Expired - Fee Related
- 1998-10-29 DE DE19849863A patent/DE19849863B4/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4474167A (en) * | 1977-05-02 | 1984-10-02 | Mccabe Francis J | Latch for a butterfly damper |
| US4467824A (en) * | 1981-06-13 | 1984-08-28 | Strulik Wilhelm P | Self-closing fire damper for duct |
| GB2230951A (en) * | 1989-04-14 | 1990-11-07 | Nailor Hart Ind Inc | Fusible link assembly |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2350295A (en) * | 1999-03-31 | 2000-11-29 | Flaekt Oy | Fire damper for a duct |
| GB2350295B (en) * | 1999-03-31 | 2002-06-12 | Flaekt Oy | Flue gas damper |
| GB2369571A (en) * | 2000-12-01 | 2002-06-05 | Tri Air Innovations Ltd | Air flow controller and fire damper in an air flow duct |
| GB2369571B (en) * | 2000-12-01 | 2005-01-26 | Tri Air Innovations Ltd | Air flow controller and fire damper in an air flow duct |
| US6991536B2 (en) | 2000-12-01 | 2006-01-31 | Kent Tooling And Components Limited | Air flow controller and fire damper in an air flow duct |
| US7195032B2 (en) * | 2003-01-30 | 2007-03-27 | Beth-el Zikhron-Ya′Aqov Industries, Ltd | Unidirectional, adjustable flap valves |
| WO2004072531A1 (en) * | 2003-02-11 | 2004-08-26 | Truss Holdings Pty. Ltd. | Damper with rotary valve |
| CN110114122A (en) * | 2017-08-28 | 2019-08-09 | 扎斯特瑞特制造有限责任公司 | Ventilation safety cabinet equipped with thermotropic fluctuation dampers |
Also Published As
| Publication number | Publication date |
|---|---|
| DE19849863A1 (en) | 1999-05-06 |
| FR2770411A1 (en) | 1999-05-07 |
| GB2330772B (en) | 2001-06-06 |
| DE19849863B4 (en) | 2009-10-01 |
| GB9823551D0 (en) | 1998-12-23 |
| FR2770411B1 (en) | 2000-01-21 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20141029 |