Fire curtain

A fire curtain has its top fixed to a top framework of a building, the frwork including arrangements for spraying a fluid onto the curtain having two walls fastened together along its bottom and its vertical sides. The fluid spraying arrangements spray at least one interior face of one wall with the fluid.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention concerns a fire curtain. 
2. Description of the Prior Art 
Fire curtains are used in buildings, and in particular in establishments 
receiving the public, to prevent fires propagating between different parts 
of the building. Fire curtains are used to compartmentalize large spaces 
and are generally made from a fabric limiting the propagation of flames 
and smoke during a fire. 
These curtains are generally deployed only in the event of a fire, being 
folded up normally. 
It is known in the art to uniformly spray one of the fabric sides of 
conventional fire curtains to limit the propagation of heat and the 
increase in the temperature of the canvas fabric used in these curtains. 
However, such curtains require the provision at floor level of drains for 
recovering the water at the bottom of the curtain. These recovery drains 
form obstacles and cannot be concealed by any floor covering. 
Moreover, the water can be recovered correctly only if the curtain is in 
its normal vertical position. However, it is not rare for the curtain to 
be deflected from this vertical position when it is deployed in the event 
of a fire due to the effect of wind or because of obstacles. The water is 
then not recovered properly in the drains, if at all, causing flooding of 
the premises. 
An aim of the present invention is to remove the aforementioned drawback by 
proposing a fire curtain increasing the protection of premises adjoining a 
part in which a fire has broken out. 
SUMMARY OF THE INVENTION 
The present invention includes a fire curtain having its top fixed to a top 
framework of a building, the framework including means for spraying a 
fluid onto the curtain which has two walls fastened together along its 
bottom and its vertical sides, the fluid spraying means being adapted to 
spray at least one interior face of one wall with the fluid. 
Using this double-wall curtain, forming a pocket, and spraying the interior 
faces of the walls, the water is recovered within the curtain itself. 
It is therefore no longer necessary to provide recovery drains in the 
floor. 
Moreover, the risk of flooding the protected premises is entirely avoided. 
In one preferred embodiment of the present invention, at least one of the 
vertical sides comprises near the bottom of the curtain means for 
evacuation of the fluid expelled from the spraying means. A wall of the 
building adjacent the vertical side includes fluid recovery means. 
Thus if a high flowrate of fluid is used, it may be necessary to evacuate 
at least part of the fluid. The evacuation means enable removal of the 
fluid via one or both vertical sides of the curtain, at the level of the 
vertical walls. 
In a preferred embodiment of the invention at least one of the vertical 
sides comprises a fluid evacuation orifice at a predetermined height above 
the bottom of the curtain. 
Consequently, when the fluid used is a liquid such as water, a 
predetermined volume of the liquid accumulates in the bottom part of the 
curtain. The liquid trapped in the bottom part of the curtain ballasts it, 
so achieving effective tensioning of the curtain. 
There is therefore a perfect seal against smoke or gas at floor level. 
Moreover, the curtain ballasted in this way is held vertical even in the 
event of horizontal wind loading. 
The bottom of the curtain may mate exactly with the floor and any objects 
that happen to be under the curtain when the latter is deployed. 
In another preferred embodiment of the invention the two walls are linked 
by strips of equal length forming spacers. 
These strips forming spacers hold the two walls of the curtain in face to 
face relationship. 
In a preferred version the strips forming spacers are adapted to break when 
subjected to a tension force substantially equal to the weight of one of 
the two walls. 
In this way, should one of the walls fall down, the other wall remains 
suspended from the top framework of the building. 
Protection against fire is therefore guaranteed even if one part of the 
building collapses, a curtain of water being interposed between the 
remaining curtain and the fire. 
Other features and advantages of the invention will be clear from the 
following description. 
The accompanying drawings are given by way of non-limiting example.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring first to FIG. 1, a fire curtain 10 is fixed to a top framework 21 
of a building 20. 
The latter may be a large building for industrial use or intended to 
receive a large number of persons, for example. 
In the usual way it comprises a top framework 21 supporting the roof. 
The curtain 10 comprises two walls 11 fastened together along its bottom 
11d and its vertical sides 11e. 
The two walls 11 have their top ends 11c fixed to the top framework 21 
across the whole width of the curtain 10. Thus the curtain 10 forms a 
pocket suspended from the top framework 21. 
The walls 11 are made from class M1 or M0 fabric for limiting the 
propagation of flame and hot or inflammable gases and for thermally 
insulating the two parts of the building separated by the curtain 10. 
The walls are constructed, for example, from woven glassfiber fabric and 
glassfibers, woven polyester/cotton fabric or an armature of continuous 
ceramic fibers. The fabric is waterproof or allows only slight sweating of 
water in the case of a woven polyester/cotton fabric. 
Means 22 for spraying a fluid onto the curtain are provided on the top 
framework 21 of the building 20. 
In accordance with the invention, the spraying means 22 are adapted to 
spray the fluid onto at least one interior face 11a of a wall 11, i.e. one 
of the facing faces 11a of one of the two walls 11. 
The fluid used in the example described below is water. A different liquid 
or a cooling gas could equally will be used. 
As shown in FIG. 3, at least one of the vertical sides 11e comprises near 
the bottom 11d of the curtain 10 means 12 for evacuating the fluid from 
the spraying means 22. 
A wall 26 of the building 20 adjacent the vertical side 11e of the curtain 
10 includes fluid recovery means 28. 
In this example the evacuation means 12 comprise an orifice at a 
predetermined height above the bottom 11d of the curtain 10. 
Water escaping via the orifice 12 is recovered in the recovery means 28 
which may include a pump device 28, possibly recycling the water to the 
spraying means 22. 
As shown clearly in FIG. 2, the evacuation orifice 12 may be at a height of 
approximately 250 mm above the floor 31 and the bottom 11d of the curtain 
10, i.e. equal to approximately 1/40th the total height of the curtain, so 
that a volume of water remains trapped within the curtain 10 with its two 
walls 11. 
The accumulation of water in the bottom part of the curtain 10 stabilizes 
the latter and tensions it correctly, as well as providing a seal at the 
level of the floor 31 between areas separated by the curtain 10. 
At the end of use of the fire curtain, or in order to maneuver it, the 
volume of water trapped in it may be removed by an electromechanical valve 
and flexible hose inserted into drain orifices 12 on each lateral side 11e 
of the curtain 10. 
The spraying means 22 comprise two series of nozzles 30 disposed on the top 
framework 21 of the building 20. The nozzles are adapted to spray a 
respective interior face 11a of each wall 11, independently of each other. 
One or other of the walls may be sprayed, or both at the same time. 
The spraying means 22 comprise water feed pipes 32 equipped with nozzles 
uniformly distributed across the width of the curtain 10, i.e. along the 
top 11e of the curtain 10. 
The spray nozzles 30 form a curtain of water over all of the interior face 
11a of a wall 11. 
In the event of a fire, this interior irrigation with water leads to 
evaporation of the water procuring a convection current and cooling of the 
members interior to the curtain 10, such as the spray system 30, 32 itself 
or the part of the framework 21 supporting the curtain. 
As shown in FIG. 5, the two walls 11 are linked by strips 13 of equal 
length forming spacers to hold the two walls 11 parallel to each other. 
The strips 13 may be straps made from the same fabric as the walls 11. 
The strips 13 can be between 0.5 m and 1.5 m long, so determining the 
distance between the two walls 11. This distance is preferably between 0.8 
m and 1 m. 
The strips 13 forming spacers are adapted to break at a traction force 
substantially equal to the weight of one of the walls 11. 
Thus if one part of the top framework 21 collapses with one of the walls 
11, the strips 13 have a breaking capacity calculated to allow the strips 
13 to be torn so that the bottom wall, on the side of the remaining area 
of the building, remains in place. 
Accordingly, as shown in FIGS. 2 and 3, a rupture area 21a is provided in 
the framework 21 to enable one part of the building 20 to collapse, 
leaving the adjacent part stable. The curtain 10 of the invention extends 
substantially under this rupture area 21a. 
The curtain 10 comprises a plurality of strips 13 regularly distributed 
along its length, as shown in FIG. 5, and a plurality of strips 13 
superposed over the height of the curtain, as shown in FIG. 2. 
Each strip 13 forming a spacer includes a connection piece 14 adapted to 
slide on a cable or tape 15 having a first end 15a fixed to the bottom 11d 
of the curtain and a second end 15b fixed to a winder 23 fastened to the 
top framework 21 of the building 20. 
When the cable or the tape 15 is wound onto the winder 23, all of the 
strips 13 forming spacers are folded against each other so that the two 
walls 11 are folded up near the top framework 21 of the building 20. 
Protecting plates 24 are preferably fixed to the top framework 21 and 
extend towards the floor 31 a sufficient distance to conceal all of the 
curtain 10 when it is in the folded position as shown in FIG. 4A. These 
plates have a length equal to that of the curtain, between 80 m and 100 m, 
and a depth of approximately 0.5 m. 
This depth substantially corresponds to the overall size of the folded 
curtain 10 if the latter has a height of approximately 10 m in the 
deployed position. 
Similarly, protection plates 25 are fastened to vertical walls 26 of the 
building and extend parallel to the curtain 10, on each side of the 
latter. 
An area 27 can be delimited by the plates 25, the vertical wall 26 adjacent 
a side 11e of the curtain 10 and a second lateral wall 26a parallel to the 
first vertical wall 26 to accommodate the water spray and recovery control 
mechanisms. 
The protection plates 24 and 25 are preferably made from a class M0 
fireproof material. 
Operation will now be described with particular reference to FIGS. 4A 
through 4E. 
In the event of a fire, deployment of the curtain 10 is commanded either 
manually or automatically in accordance with an instruction given by a 
smoke detector, for example. The winder 23 is then rotated, for example, 
by a motor (not shown), and the cable or tape 15 is progressively unwound. 
The strips 13 slide along the cable 15 as this happens so that the walls 
11 are unfolded. 
Spraying of the curtain is then commanded, either on both interior faces 
11a or only on the face 11a of the wall exposed to the fire. 
If the framework 21 of the building 20 breaks in the area on fire, the 
other wall 11 remains suspended from the remaining part of the building 
10. 
Control means known in themselves may be adapted to command automatic 
starting of the spray nozzles 30 spraying water onto the wall 11 that 
remains in place, alternating the operation of the two series of nozzles 
30. 
The curtain of the invention thus compartmentalizes large buildings and 
therefore provides a very effective means of limiting the propagation of 
fires. 
Of course, many modifications may be made to the example described above 
without departing from the scope of the invention.