GB2296658A - Fire curtain system - Google Patents

Abstract

The system has a curtain 1 which is lowered to seal off an opening 2 from a fire. The curtain is attached to fixed support 3 and is initially wrapped around a movable roller 4 in its retracted position. In use the roller is moved downwards from the fixed support to unroll the curtain and seal off the opening. The roller is preferably equipped with a motorised drive at both ends. The curtain may be fabricated from glass or ceramic fibres coated with a silicone elastomer. The system may be used in e.g. aircraft hangars or ships. <IMAGE>

Description

FIRE CURTAIN SYSTEM The present invention relates to a fire curtain system incorporating a fire curtain and means to drive the curtain between extended and retracted positions.

According to the present invention a fire curtain system comprises a curtain having a first end attached to a fixed support in use and a second end attached to a support which is movable between retracted and extended positions relative to the fixed support, wherein the movable support comprises a roller around which the curtain is wrapped in its retracted position.

Typically the system further comprises drive means for rotating the roller, such as an endless belt. Preferably however, the drive means moves with the roller between the retracted and extended positions, thus providing extra weight at the bottom of the curtain when it is in its extended position.

Typically the drive means comprises a motor such as an electric motor which is connected to and movable with the roller. Preferably the drive means is entirely selfcontained (typically including a drive motor and suitable gearing) and moves up and down with the curtain.

Typically the drive means comprises a pair of drive means, each connected to a respective end of the roller.

Typically each respective one of the pair of drive means is mounted in a mounting bracket fixed to a respective side of an opening which includes the fixed support to which the fire curtain system is attached.

Typically the curtain comprises one or more fire retardant layers and a plurality of support cables. Part of the curtain (such as the fire retardant layer) may be folded in concertina form and not wrapped around the roller when the curtain is in its retracted position.

In some applications the curtain needs to be designed to withstand an intense fire such as a hydrocarbon fire.

Suitable materials which can be used to form the fire retardant layer(s) of the curtain are stainless steel foil contained in glass or ceramic fabric bags, or glass or ceramic fabric coated with silicone elastomer. Preferably the fire retardant layer of curtain has a three layer construction, with the inner layer formed with stainless steel foil contained in glass or ceramic fabric bags, and the two outer layers formed with glass or ceramic fabric coated with silicone elastomer.

Alternatively the curtain may be a lightweight curtain comprising a single layer of ceramic fabric coated with a polymer such as silicone or neoprene.

Typically the curtain is formed with a plurality of vertical or horizontal panels.

The fire curtain may be installed in use in any space requiring partition during a fire, for instance below decks on a ship or in an aircraft hanger.

A number of embodiments of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 shows the basic elements of the system; Figure 2 is a cross-section along a line A-A in Figure 1 showing the curtain drive system; Figure 3 is a cross-section along a line B-B in Figure 1 showing the guide system; Figure 4 is a cross-section of part of the curtain; Figure 5 shows an inner curtain joint; Figure 6 shows an outer curtain joint; Figure 7 is a cross-section of the roller in its fully extended position with the curtain clamping bar removed; Figure 8 is a close up of the curtain clamping groove shown in Figure 7; Figure 9 is a perspective view of the roller with the curtain clamping bar removed; Figure 10 is a cross-section of an alternative method of fixing the curtain to the roller;; Figure 11 shows an alternative, lightweight form of curtain; Figure 12 is a side view of the curtain shown in Figure 11; Figure 13 is a cross-section along a line A-A in Figure 11; Figure 14 is a cross-section along a line B-B in Figure 11; Figure 15 is a cross-section along a line C-C in Figure 14; Figure 16 is a cross-section showing a single concertina curtain system; and Figure 17 is a cross-section showing a double concertina curtain system.

Figure 1 shows the fire curtain system in a partially lowered state. The curtain 1 is raised and lowered to seal off an opening 2 to prevent fire from passing through the opening. The curtain 1 is attached to a fixed head rail 3 at one end and to a roller 4 at the other end. When the curtain is in its retracted position the movable roller 4 lies adjacent to the fixed head rail 3 and the curtain 1 is wrapped around the roller. In order to lower the curtain, the roller 4 is rotated by two drives (not shown) which are movable with the roller and rotate the spindle 6 in a direction indicated by arrow 5. As the roller 4 rotates, the curtain unrolls and the roller 4 moves downwards away from the fixed head rail and in its fully unrolled state the roller lies adjacent to the base 7 of the opening.

Figure 2 is a cross-section on a line A-A in Figure 1 showing one side of the fire curtain drive system (an identical driver is fixed to the other end of the roller 4). The drive system moves within a vertical drive mounting bracket 20 attached to the wall 26 which ensures that the roller and motors have all the necessary degrees of freedom to operate freely.

The principle features of the drive system are: i) an electric motor 21, coupled to ii) a reversible reduction gear 22, fitted with iii) a holding brake 23, and iv) a mechanical centrifugal speed governor 24. The system also has the following features: v) End of travel limit switches (not shown).

vi) A facility to close the curtain without power.

vii) A battery back-up system to support the holding brake to prevent accidental closure in the event of a short term power failure, typically 1 to 4 hours.

The drive system also employs the technique of operating the single roller tube 4 with two separate motors, one at each end. The principal advantages of this are: i) Better torsion characteristics of the roller tube.

ii) A fail safe system where one drive unit is capable of sustaining and/or stopping the entire weight of the curtain, although not necessarily capable of opening the curtain.

The motor 21 extends out of a vertical slot 40 which extends along the length of the mounting 20. The drive shaft casing 41 is mounted in a vertical slot 40 with a pair of rollers or other form of bearing (not shown). The curtain is sealed by a flexible sealing strip 39 as it unrolls. The flexible sealing strip 39 is attached to the mounting bracket 20, and both the mounting bracket 20 and sealing strip 39 extend from the top to the bottom of the opening 2.

Figure 3 is a cross-section on a line B-B in Figure 1 with the curtain 1 in its fully extended state. The drive system moves within mounting bracket 20 with a slot 38 for the spindle 6. Typically, the curtain is provided to seal off an opening for example between upper and lower decks 36,37 on a ship. In its fully extended position shown in Figure 3 a fire deflector skirt 33 (provided on both sides) lies on the deck 37. The lower skirt rolls up with the curtain. The upper end of the curtain is also terminated by fire deflector skirts 34 on both sides. As can be seen in Figure 3, the curtain is fixed to the upper deck 36 by a curtain mounting bracket 35.

Where there is a "hazard direction" (i.e. a direction where a fire is more likely to develop) then the curtain is installed such that the roller 4 lies on the opposite side.

For example, the "hazard direction" (if any) in Figure 3 will lie to the left of the curtain in Figure 3. In instances where the hazard is on both sides, the drive system will be protected by the application of fire proof covers.

The construction of curtain 1 is shown in Figures 4, 5 and 6. Figure 4 shows a cross-section through the curtain on a line C-C in Figure 1. The curtain consists of three layers: inner curtain 51 and two outer curtains 52,53. The inner curtain comprises stainless steel foil contained in glass or ceramic fabric bags. The outer curtains comprise glass or ceramic fabric coated on the outside with silicone elastomer. Each layer is constructed with vertical panels nominally one metre wide (5 of such panels are shown schematically in Figure 1). As shown in Figure 4, the joints 54,55 and 56 do not lie next to each other so that there is no direct joint path through the curtain.

The inner curtain joint 54 is shown in more detail in Figure 5. Each panel comprises an inner layer of stainless steel foil 61 enclosed in a glass or ceramic fibre bag 62,63. The joint 54 encloses two stainless steel cables 64,65 which are themselves located in a glass or ceramic fibre bag (not shown). This latter bag is stitched on each side as shown at 66,68 and along its length centrally at 67. The bag is stitched to the bags 62,63 at its ends.

The glass or ceramic fibre bags 62,63 are wrapped around each other at the joint.

Figure 6 shows the outer curtain joint 56 in more detail. The panel joint is secured with stitching 71,72 and protected with a cover strip 73 (made of the same material as the outer curtain) which is attached to the outer curtain with stitching 74,75.

The inner and outer curtains are not joined except for the top and bottom which are attached to the roller 4 and the fixed head rail 3. A typical curtain has 24 panels which gives a total width of approximately 21 metres.

Figure 7 shows a cross-section through the roller 4 when the curtain is fully unrolled, with clamping bar 81 removed. The curtain 1 (indicated in dotted lines in Figure 7) is clamped either within a groove 80 by a clamping bar 81 (shown in Figure 8) or by fixing to the outer diameter of the roller with a clamping bar of a similar form to 81 (i.e. curtain not retained in groove).

The curtain may be fixed with one or more clamping bars.

The roller 4 is illustrated in the perspective view of Figure 9. Groove 80 extends across the width of the roller 4 and includes a number of tapped holes 82-86. Five tapped holes 82-86 are shown in Figure 9 but the number may be varied for any particular applications. The clamping bar 81 is illustrated in Figure 9 removed from the slot 80.

The clamping bar 81 has counterbored holes 82'-86' which correspond with the tapped holes 82-86 in the base of the groove 80. The curtain 1 is fixed in the drive 80 by laying the lower edge of the curtain 1 around the groove 80 as shown in Figures 7 and 8 and punching holes in the curtain with a tube drill in the positions of the tapped holes 82-86. The clamping bar 81 is then placed into the groove 80 and cap screws are screwed into the holes 82-86, 82'-86'.

The clamping arrangement of Figures 7-9 is illustrated with a curtain 1 which may be single ply or three ply as illustrated in Figures 4-6. Instead of clamping the three ply curtain in a single groove 80, each layer of the curtain may be clamped separately as illustrated in the alternative embodiment of Figure 10. In this case the inner curtain 51 is clamped in a central clamping groove 90 and the outer curtains 52,53 are clamped in a pair of outer clamping grooves 91,92 respectively. The curtains 51-53 are clamped into their respective clamping holes 90-92 by clamping bars similar to the clamping bar 81 shown in Figures 8 and 9. The separate clamping arrangement of Figure 10 ensures that water can easily flow out of the bottom of the curtain if it collects between the outer curtains 52,53.

An alternative, lightweight curtain construction is illustrated in Figures 11-15. A front view of the lightweight curtain 100 is shown in Figure 11. The curtain 100 is formed by a series of one meter high horizontal panels 101-103 and is supported by a series of support cables 104 to 106. The lower panel 103 and the support cables 104-106 are connected to a roller 107. Three panels 101-103 and three support cables 104-106 are shown in Figure 11 but the number of panels and/or support cables may be varied for any particular design.

Figure 12 is a side view of the curtain 100 shown in Figure 11. The panels are connected alternately (and for a larger curtain further panels may be added in a similar arrangement). Each panel comprises an inner ceramic fabric layer 130 (typically a monofilament yarn formed into a fabric) which is suitable primed and coated with polymer 108. The polymer coating 108 may be any polymer such as silicone or neoprene. The panels are connected in panel joint regions 109,110. The curtain has a pair of lower skirts 42,43.

The lower panel joint region 110 is illustrated in Figure 13, which is a cross-section along a line A-A in Figure 11. The end 120 of panel 102 is stitched to the end 121 of panel 103 across the width of the curtain 100 as indicated at 111,112. The joint 110 is braced by metallic support plates 113,114 which also extend across the width of the curtain 100. The support plates 113,114 are fixed by bolts at approximately 400mm intervals across the width of the curtain 100 although this could be different for other applications.

Figure 14 is a cross-section along a line B-B in Figure 11 through a support cable 106. The support cable 106 passes through an eyelet 122 formed in the support plate 113. Figure 15 is a cross-section along the line C-C in Figure 14. Fixing bolts 125,126 fix the support plates 113,114 on either side of the eyelet 122. The bolt heads are counterbored or countersunk and are sub-flush with the outer surface of the support plate 113. The bolt ends are sub-flush with the outer surface of the support plate 114.

The 'hazard direction" if any, will be on the left-hand side of Figure 14. This will reduce the heating effect on cable 106 and support plate 113 since they will be shielded by the fire retardant layers 101,102,103.

Alternatively the cable 106 may hang loosely between the lower panel 103 and support plate 113. The support cable 106 may also be on the outside of the curtain, i.e.

on the right hand side of support plate 113.

The system is designed to provide a fire barrier that can contain a hydrocarbon fire, minor explosion or objects falling against it. The curtain is designed to contain a fire for at least 30 minutes. The curtain is simple to install and only requires a vertical track fixed eg by welding or bolting at each side of the aperture. Any part of the system can be accessed for maintenance without specialist equipment (i.e. it can be maintained at sea).

Due to its design, all available weight is focused at the base of the curtain therefore when in the extended position this provides a very strong structure with the roller supported uniformly by cables pitched at one metre intervals which can alter depending upon application. The system is also very compact in terms of the overall head space required to house the roller in its retracted position.

In an alternative embodiment the curtain may be of a concertina type, with cables only wrapped around the roller, and the curtain folded up in its retracted position.

Figure 16 is a cross-section of a first alternative embodiment of this type. Curtain 130 is shown in its partially extended state and as can be seen the curtain 130 folds up in concertina form between the support frame 131 and the roller 132 when the curtain is in its retracted position. The curtain further comprises a number of support cables 133 which are also attached to the support frame 131. The fire retardant layer 130 of the curtain is attached via attachment frame 134 to the axle 135 of the roller 132. The support cable 133 is wrapped around the roller 132 and unrolls as the roller 132 is rotated clockwise and the curtain moves into its extended position.

Figure 17 is a cross-section through a second alternative embodiment of the above type. Figure 17 shows a double curtain arrangement in which two single curtain arrangements of the type shown in Figure 16 are arranged back to back and the axles 140,141 of the rollers 142,143 are connected as indicated at 144.

The "hazard direction" (if any) in Figure 16 will be on the right-hand side, whereas the double curtain arrangement of Figure 17 is equally effective with a hazard direction on either side of the curtain.

Claims (15)

1. A fire curtain system comprises a curtain having a first end attached to a fixed support in use and a second end attached to a support which is movable between retracted and extended positions relative to the fixed support, wherein the movable support comprises a roller around which the curtain is wrapped in its retracted position.

2. A system according to claim 1, further comprising drive means for rotating the roller to cause the curtain to unwind from the roller whereby the roller moves from its retracted position towards its extended position.

3. A system according to claim 2, wherein the drive means is movable with the roller.

4. A system according to claim 3, wherein the drive means comprises a motor connected to and movable with the roller.

5. A system according to claim 3 or 4, wherein the roller has first and second ends, and the drive means comprises a pair of drive means, each of the pair being attached to a respective end of the roller.

6. A system according to claim 5, wherein the fixed support comprises one side of an opening having a plurality of sides, and each of the pair of drive means is mounted in a mounting bracket fixed to a respective side of the opening.

7. A system according to any of the preceding claims, wherein the curtain comprises stainless steel foil contained in glass or ceramic fabric bags.

8. A system according to any of the preceding claims, wherein the curtain comprises glass or ceramic fabric coated with silicone elastomer.

9. A system according to any of the preceding claims, wherein the curtain is constructedowith three layers.

10. A system according to claims 7, 8 and 9, wherein the inner layer comprises stainless steel foil contained in glass or ceramic fabric bags, and the two outer layers comprise glass or ceramic fabric coated with silicone elastomer.

11. A system according to any of the preceding claims, wherein the curtain comprises a single layer of ceramic fabric coated with polymer.

12. A system according to any of the preceding claims, wherein the curtain comprises one or more fire retardant layers and a plurality of support cables.

13. A system according to any of the preceding claims, wherein part of the curtain is folded in concertina form when the curtain is in its retracted position.

14. A system according to claim 12 and 13, wherein the support cables are wrapped around the roller and the one or more fire retardant layers are folded in concertina form and not wrapped around the roller when the curtain is in its retracted position.

15. A fire curtain system substantially as hereinbefore described with reference to the accompanying drawings.