The present invention relates to fire and smoke curtains and more particularly to apparatus for controlling the descent of a curtain from its roller,

Fire and smoke curtains when not deployed are wound around a roller.

Typically the roller contains a motor, brake and gear box arrangement, with the brake usually ON to hold the curtain up. In the event of a fire, the brake is released, and the curtain closes, however its decent is controlled by the back emf of the motor. The motor is then used to rewind the curtain after deployment.

This arrangement requires a constant power supply to be fed to the roller, which over the lifetime of a curtain can be costly. The object of the present invention is to provide an alternative arrangement for controlling the descent of a fire or smoke curtain.

According to the invention there is provided a barrier comprising

a roller

a curtain for rolling onto and deployment from the roller,

a bottom bar, attached to the bottom of the curtain, for weighting the curtain for deployment,

a friction brake arranged to brake the roller and to slow deployment of the curtain.

Typically the roller, or a shaft supporting the roller, extends outside the headbox, and the friction brake comprises a friction element that acts on the roller or the shaft outside the headbox. Typically the friction element may be a strap, in particular a wear resistant strap, for example of leather, which acts in tension on the roller or shaft. Typically the strap may be attached by a spring to the headbox end, or a wall, to hold the strap in tension. The tension in the strap can be adjusted by adjusting the spring tension, or altering the distance between the spring and its attachment to the headbox end or wall. In use, on deployment of the curtain, the strap acting against the roller, slows the speed of rotation of the roller, controlling the descent of the curtain. The higher the tension in the spring, the greater the resistance on the roller, the slower the rotational speed and thus slowing the deployment of the curtain.

In an alternative, the friction element is provided as a friction pad, acting against the roller or its supporting shaft. Usually the friction pad will be provided on a bar, which is attached to the wall or headbox end via a strut. The pad can be urged against the roller by a spring acting between the strut and the pad, the length of the bar being adjustable by a nut.

Typically the curtain will be held in it retracted position by a fusible link. In some embodiments this may be positioned between an outside edge of the headbox and/or the roller extension outside the headbox. The fusible link is fusible

between57-150°C. Alternatively the fusible link may include a fusibale link securing a drive gear on to the roller.

In a further alternative, the friction element is provided as a sprung loaded shaft. The spring is designed to act against rotation of the roller, thus slowing the descent of the curtain.

To help understanding of the invention, a specific embodiment thereof will now be described by way of example and with reference to the accompanying drawings, in which:

Figure 1 is a front view of a fire and smoke curtain according to a first embodiment of the present invention;

Figure 2 is a scrap side view of the roller of the curtain of Figure 1 ;

Figure 3 is a scrap front view of the roller of Figure 1 ;

Figure 4 is a scrap side view of a roller according to a second embodiment of the invention;

Figure 5 is a scrap front view of the roller of Figure 4; and

Figure 6 is a perspective view of a fire and smoke curtain according to the third embodiment of the present invention. Referring to Figure 1 , the curtain arrangement 1 there shown includes a curtain as such 2, which when not deployed is wound on a roller 4. The roller is provided essentially within a headbox 6, in a ceiling 8. The curtain is provided with a bottom bar 10 which weighs the curtain for descent, but can also be used to close the headbox when the curtain is retracted onto the roller.

Side guides 12 are also provided to contain side edges 14 of the curtain. They extend from the headbox 6 on the ceiling to the floor 18, and have in-turned lips (not shown), between which the edges of the curtain are retained.

Unusually the roller is not provided with a motor, gearbox and brake arrangement, which generally maintain the curtain in the retracted position and also control the descent of the curtain on deployment. As shown in Figures 2 and 3, the curtain is held in its retracted position on the roller, by a fusible link 20.

An extension 22 of the roller 2 is provided extending out of the headbox 6. The fusible link 20 is provided between the outside of the headbox and the extension 22 of the roller. A peg 24 mounted on the headbox 6 holds one portion 26 of the fusible link, while the other portion 28 of the fusible link is connected to the extension 22. These portions are held together by a material 30 having a low melting point range typically between 57-150°C. This acts to hold the curtain on the roller under normal condition, preventing rotation of the roller within the headbox, but on sufficient temperature rise, the material 30 will melt, releasing the portions 26, 28 of the fusible link, allowing rotation of the roller and deployment of the curtain.

On release of the fusible link, the curtain, under the weight of the bottom bar 10, will mi-roll from the roller, and descend to the floor. In the absence of any other factor, the bottom bar and curtain could fall rapidly to the floor, which is a potential safe hazard and could harm occupants escaping from the fire, or causing other damage to the surrounding finishes. To control the descent of the curtain and bottom bar, a frictional force is provided to resist rotation of the roller 2. As shown a strap 34, typically a wear resistant material, for example leather, is provided around the roller, acting against its rotation. The strap is connected at both ends 36, 38, to the headbox 6. At one end 36, the strap is connected to the pin holding 24 holding one portion 26 of the fusible link 20. However, the strap 34 could alternatively be attached to another peg extending from the headbox. The other end of the strap 38 is attached to a tension spring 40, which is connected to a bolt 42 passing through a strut 44 again extending from the headbox 6. The length of the bolt passing through the strut can be adjusted by turning of the bolt, or a nut 46 on the bolt, which adjusts the tension on the spring 40 and thus the tension in the strap 24. The friction on the roller from the strap, acts against rotation of the roller. However, on breaking of the fusible link, the weight of the bottom bar overcomes the friction on the roller, which does rotate to deploy the curtain. However, the speed of rotation is reduced by the friction effect of the strap, thus controlling the speed of deployment of the curtain 2 and bottom bar 10. The speed of descent of the curtain 2 and bottom bar 10 can be adjusted by adjusting the tension in the strap 34, by adjusting the extension of the bolt 42, though the strut 44, by adjusting the nut 46.

Now turning to Figures 4 and 5, the curtain 102 thereshown is held in its retracted position by a fusible link 120. The roller 104 is provided with a toothed gear wheel 150. A first portion 126 of the fusible link is attached to a peg 124 extending from the headbox 106. The other portion 128 of the fusible link is connected to the first portion 126 via a material 130 having a low melting point range typically between 57-150°C. This second portion 128 of the fusible link extends between the teeth 152 of the gear wheel 150 prevent rotation thereof and thus rotation of the roller 104, and thus deployment of the curtain. However, on sufficient temperature rise, the fusible link will break, releasing the gear wheel, thus allowing the roller to rotate and deploy the curtain.

Again a friction force applied to the roller controls the descent of the curtain. As shown a frictional pad 134 is applied to the roller. The pad is held on a threaded bar 136, which extends through a strut 144 extending from the headbox 106. The extent of the extension of the bar 136 through the strut 144 can be adjusted by a nut 146, and a compression spring 140 is provided on the bar 136 between the friction pad and the strut. This acts to urge the friction pad against the roller 104. As described above, the action of the pad 134 against the roller 104 acts to prevent rotation of the roller, and thus to control the descent of the curtain 102 and bottom bar 110. Again the amount of friction applied to the roller can be adjusted by turning the bolt 146 to adjust the pressure of the pad 134 against the roller. Turning now to Figure 6, the curtain system 201 thereshown, including a roller

204 having a spring loaded shaft. The spring 234 acts to hold the roller 204 in a particular position, one in which the curtain 202 is fully wound thereon. However, the strength of the spring is not sufficient to hold the curtain in the wound position, and in the absence of any other force, the curtain would deploy, under the weight of the bottom bar 210, However, the deployment would be controlled by the spring resisting the rotation of the roller. Thus the descent of the curtain would not be in free fall, but would be slowed.

Thus other means, for example the fusible links, as described in the previous embodiments, or other means for maintaining the curtain in its retracted or wound position will be required.

To rewind the curtain after deployment, the curtain can be lifted by hand, the spring acting to return the roller to its position effectively taking some of the weight of the curtain and making lifting easier. The roller automatically rolls to its position under the influence of the spring, winding the curtain onto the roller. The curtain can then be held in the retracted position, holding the roller in position, by the retention means.

The invention is not intended to be restricted to the details of the above- described embodiment. For instance, the fusible link of Figures 5 & 6 could be used with the tension means of Figure 2 & 3 or vice versa.