GB1599041A

GB1599041A - Fire safety systems

Info

Publication number: GB1599041A
Application number: GB560777A
Authority: GB
Original assignee: KG SMOKE DISPERSAL Ltd
Current assignee: KG SMOKE DISPERSAL Ltd
Priority date: 1978-05-08
Filing date: 1978-05-08
Publication date: 1981-09-30

Description

(54) IMPROVEMENTS IN OR RELATING TO FIRE SAFETY SYSTEMS (71) We, K. G. SMOKE DISPERSAL LIMITED, a British Company, of Heath Common, Storrington, Sussex RH20 3AD, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to fire safety systems and to smoke vents for use in such systems.

In our Patent Specification No 1 326 112, there is claimed a fire safety system including a smoke detector installed in a building, an aperture in a wall of said building, closure means for said aperture arranged to provide, in the open position of said closure means, separate openings for ingress and egress of air, locking means for retaining said closure means in the closed position, and means controlled by said detector for releasing said locking means and thus opening said closure means when smoke is detected by said detector.

In the particular system described in the said Patent Specification No 1326112, the closure means consist of, or include, a panel which is pivotable about a horizontal axis to provide said separate openings for ingress and egress of air, and a particular panel of this kind forms the subject matter of our Patent Specification No 1 326 113, in which there is claimed a smoke vent including a panel adapted to close an aperture in a wall of a building. said panel being mounted to pivot about a horizontal axis located below the centre of gravity of the panel, and dividing the panel into a part above the pivot axis and a part below the pivot axis, spring means urging the part of the panel above the pivot axis outwardly with respect to the building, and electromagnetically controlled locking means capable of holding said panel in the closed position against the action of said spring means.

In some buildings, it may be necessary to provide relatively large panels in order to obtain the required opening areas for the ingress and egress of air. If relatively large panels are mounted in a relatively narrow corridor, they may constitute a hazard, or an obstacle, and may conse quently be unacceptable, particularly if the corridor constitutes an escape route for use in the case of fire.

It is an object of the present invention to provide an alternative form of closure means for a system as claimed in Patent Speciflcation No 1 326 112, which does not suffer from the above disadvantage.

The invention consists in a fire safety system as claimed in Claim 1 of Patent Specification No 1 326 112, wherein said closure means consist of, or include, a movable louvre system.

Movable louvre systems are known which consist of a plurality of pivotally-mounted louvre blades and control means for adjusting the angular position of the blades.

Such a louvre system is suitable for use in a fire safety system in accordance with the present invention, and, in this case, two sets of blades are preferably provided, one set being designed, when open, to promote the ingress of air and the other set being designed, when open, to promote the egress of smoke. In addition, bias means are preferably provided to urge the control means in the direction necessary to rotate the blades into the open position, while the locking means are effective to hold the control means in the position in which the louvres are closed.

When a louvre system in accordance with the invention is in use, the two sets of blades are pivotable about horizontal axes.

These two sets are arranged in an aperture in a wall of a building with one set occupying the lower part of the aperture and the other set occupying the upper part of the aperture. Preferably the blade-adjusting means are arranged so that, when said louvre system is open, the blades in said one set slope inwardly and upwardly with respect to said wall, while the blades in the other set slope outwardly and upwardly with respect to said wall.

It is to be understood that in any movable louvre having horizontal blades, the arrangement is normally such that, when the louvre is closed, adjacent blades overlap, with the lower edge of each blade located outside the upper edge of the next blade below it. Consequently, the blades in said one set can be rotated from the closed position of the louvre to the open position of the louvre by rotating them through an angle of approximately 45" so that the upper edges of the blades move inwardly and the lower edges move outwardly.So far as the blades in the other set are concerned, however, it is not possible to rotate these blades in the opposite direction so as to move them directly to the required position in which they slope outwardly and upwardly Accordingly, to move these blades from the closed to the open position, it is necessary to rotate them in the same direction as the blades in said one set, but through an angle of approximately 135 instead of only 45". Accordingly, a louvre system in accordance with the invention preferably includes a lever mechanism or a gear mechanism which enables the blades in said other set to be rotated through an angle three times as great as the angle through which the blades in said one set rotate in dependence on the movement of said control means.Said control means may be urged in the direction necessary to open the louvre system by means of a spring or a weight, or by a combination of spring force and gravity.

Preferably, the locking means also operate on the control means, and may be generally in the form described with reference to the fire safety system of Patent Specification No 1 326 113. In other words, an armature may be provided on the control means and may cooperate with an electromagnet mounted on the louvre frame or on the wall of the building in which the system is fitted.

If desired, the two sets of blades may be separately controlled, individual bias means and locking means being provided for each set.

As in the case of the panel described in Patent Specifications Nos 1 326 112 and 1 326 113, each louvre blade may be mounted to pivot about a horizontal axis located below the centre of gravity of that blade, so that the weight of the blades may be used to assist in opening the louvre.

The blades may consist of glass if the aperture is required to transmit light into the building even when the louvre system is closed. Alternatively, they may consist of metal such as aluminium or steel if light transmission is not required.

In a modified form of the invention the closure means consist of a louvre system and a panel which is pivotable about a horizontal axis.

In an arrangement in accordance with this form of the invention, the louvre system provides one of said openings and the panel provides the other of said openings.

Preferably the panel is arranged above the louvre system. and, in this case, it will be understood that the louvre system, when open, provides an opening for the ingress of air, while the panel, when open, provides the opening for the egress of air and smoke.

In this modified form of the invention, only one of said closure means need be automatically opened when smoke is deected, the other closure means being manually-openable. In the preferred system in which the panel is located above the louvre system, the louvre system is preferably controlled by the smoke detector, while the panel is manually-openable.

If the louvre system is arranged below the panel, the louvre blades are preferably arranged so that, in the open position of the louvre, the blades slope upwardly and inwardly. The panel, on the other hand, is preferably arranged so that, when it is open, it slopes upwardly and outwardly with respect to the wall of the building.

Methods of performing the invention will now be described with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a perspective view of one embodiment of the invention in the closed position; Figure 2 is a view similar to Figure 1 with the louvres in the open position; Figure 3 is a side view of the embodiment shown in Figure 1 in the closed posi Lion Figure 4 is a view similar to Figure 3 with the louvres in the open position; Figure 5 is a sectional view taken on the line 5:5 shown in Figure 3; Figure 6 is a side view of a part of a modified louvre system; Figure 7 is a sectional view on the line 7:7 shown in Figure 6; and Figure 8 is a perspective view of a further embodiment of the invention.

The embodiment illustrated in Figures 1 to 5 includes an upper louvre system comprising three pivotally mounted glass louvre blades 1, 2 and 3, and a lower louvre system comprising two pivotally mounted glass louvre blades 4 and 5. Each of the blades 1 to 5 is provided at each side with a semicircular mounting bracket 6, secured to the respective blade by means of adhesive. Each of the brackets 6 is provided with a pivot pin 7 (Figure 5) which passes through a suitable aperture in a side member 8 of a frame of the closure means, the pivot pin being retained in position by means of a nut 9 and a washer 10.

The blades 1, 2 and 3 are controlled by means of a vertically slidable shaft 11, and the blades 4 and 5 are controlled by a vertically slidable shaft 12. The two shafts are coupled together with lost motion by means of pins 13 and 14 secured to the shaft 12, and respectively slidable in slots 15 and 16 in the shaft 11. The two shafts are mounted for vertical motion by means of screws 17 and 18, the screw 17 being slidable in a slot 19 in the shaft 11, and the screw 18 being slidable in a slot 20 in the shaft 11 and a slot 21 in the shaft 12.

As can be seen from Figure 5, the screw 18 is fitted in a wooden framework 22 on one side of the closure means. The screw 18 passes through a hole in a channel member 23 which encloses the shafts 11 and 12.

The shaft 11 is coupled to the brackets 6 of the louvre blades 1 and 2 by means of slotted members 24, and to the bracket of the blade 3 by means of a slotted control member 25. Each of the members 24 and 25 is coupled to the respective bracket 6 by means of a pin 26. Similarly, the shaft 12 is coupled to the brackets of the blades 4 and 5 by means of slotted members 27 and pins 28.

The shaft 11 is pulled downwardly by a spring 29, and the shaft 12 is pulled downwardly by a spring 30. However, the shafts may be held in their rest positions by means of an electromagnet 31 cooperating with an armature plate 32 secured to the top of the shaft 11. It can be seen, in particular, from Figures 3 and 4 that, when the armature plate 32 is held against the electromagnet 31, the shaft 11 is retained in such a position that the blades 1, 2 and 3 are rotated in a clockwise direction until the upper louvre system is closed. In this position, a weathering strip 33 provided along the bottom edge of each louvre blade engages with the top marginal portion of the next lower louvre blade.Similarly, the shaft 12 is retained by means of the pins 13 and 14 engaging the lower ends of the slots 15 and 16 respectively in a position in which the blades 4 and 5 are rotated in a clockwise direction until the lower louvre system is closed. When the electromagnet 31 is de-energised, the spring 29 pulls the shaft 11 downwardly causing each of the blades 1, 2 and 3 to rotate through approximately 135 into the open position shown in Figure 4. Similarly, the spring 30 will pull the shaft 12 downwardly rotating the blades 4 and 5 also in an anticlockwise direction. However, because of the lost motion between the shafts 11 and 12, the blades 4 and 5 will be rotated through only 45". Thus, in the open position, the blades 1, 2 and 3 are inclined outwardly and upwardly, while the blades 4 and 5 are inclined inwardly and upwardly.These attitudes will promote the ingress of fresh air through the openings in the lower louvre system, and will promote the egress of smoke-laden air through the openings in the upper louvre system.

As explained in Patent Specification No 1 326 112, the electromagnet 31 will be controlled by one or more smoke detectors so that it is de-energised only when smoke is detected. However, in case it should ever be necessary or desirable to open the louvre systems while the electromagnet 31 is energised, a control member 25 is provided to enable the armature plate 32 to be pulled manually away from the electromagnet 31. It will be understood that, once there is an air gap between the electromagnet and the armature plate, the electromagnet will no longer be able to attract the armature plate against the action of the springs 29 and 30. Thus, so long as the electromagnet 31 is energised, the louvre systems can be manually moved into either the open or the closed position, and will remain in the selected position until manually reset.

In the modified form of the invention shown in Figures 6 and 7, the couplings constituted by the slotted members and the brackets 6 are replaced by rack and pinnion mechanisms. The two shafts 11 and 12 are replaced by a single shaft 40 having a relatively wide portion 41, and a relatively narrow portion 42. The portion 41 is provided with a rack 43, and the portion 42 is provided with a rack 44. The rack 43 cooperates with pinnions 45 secured to the blades 1, 2 and 3, while the rack 44 cooperates with pinnion sectors 46 secured to the blades 4 and 5. The shaft 40 is provided with a plurality of slots 56 cooperating with fixed pins 57 so that the shaft is capable of limited sliding vertical movement.It is normally held in its highest position by means of an electromagnet such as that shown in Figures 3 and 4 against the action of a spring similar to those shown at 29 and 30 also in Figures 3 and 4.

When the shaft 40 is held up by the electromagnet, the blades 3 and 4, for example, are rotated clockwise into the positions indicated by dash-dotted lines 47 and 48.

However, when the shaft 40 is pulled downwardly, the blades 3 and 4 are rotated anticlockwise into the full-line positions illustrated. It will be seen that the radius of the pinnion 45 is much less than that of the pinnion sector 46 and, accordingly, the blade 3 is rotated through a greater angle than the blade 4. in particular, the blade 3 may be rotated through approximately 135 and the blade 4 through approximately 450 As can be seen from Figure 7, the louvre blade 4 is secured to the pinnion 46 by means including a channel member 49 em bracing a portion of one side of the blade and secured thereto by means of adhesive.

The channel member includes a shaft 50, a first portion 51 of which is circular, a second portion 52 of which is square, and a third portion 53 of which is threaded to receive a nut 54. The circular portion 51 is rotatable in a hole in a channel member 55 fitted at the side of the closure means, while the square portion 52 engages in a similarly-shaped aperture in the pinnion sector 46.

In the embodiment illustrated in Figure 8, the upper louvre system of the previouslydescribed embodiments is replaced by a panel such as that shown in Patent Specification No 1 326 113. The panel is in the form of a glazed sash 60, pivotally mounted in a frame 61. The sash is normally held in the closed position by means of an electromagnet 62 cooperating with an armature plate 63. If the electromagnet 62 is deenergised, the upper portion of the sash is pushed outwardly by means of a spring 64.

The pivot axis of the sash is below its center of gravity and, accordingly, once the spring 64 has exerted a pressure on it, it will continue to rotate into the position shown in Figure 8 in which it is retained by means of a bracket 65.

The lower louvre system consists of two louvre blades 4 and 5 which are controlled in a manner generally similar to that shown in Figure 6. However, in this case, there is no necessity for any difference in the angle of rotation of the blades and hence a rack 66 of constant width cooperates with two similar pinnions 67 and 68. The rack 66 is normally held in its uppermost position by means of an electromagnet 69 cooperating with an armature plate 70 secured to an arm 71 extending from the shaft 66.

The shaft is urged downwardly by means of a spring 72 and can be manually controlled by means of a handle 73.

In the embodiment of Figure 8 it will be seen that, in the open position of the system, the panel 60 slopes upwardly and outwardly, while the louvres 4 and 5 slope upwardly and inwardly. Thus, as in the case of the previously-described embodiments, the system promotes the ingress of fresh air and the egress of smoke-laden air.

However, in contrast to the previous systems, the panel 60 rotates through only 45".

This arrangement is preferred in view of the normally required size and weight of the panel.

As previously stated, in a modification of the embodiment shown in Figure 8, the panel 60 is manually openable. In this case, the electromagnet 62 and the armature plate 63 may be replaced by a normal window fastening controlled by a cord or the like extending to a suitable height for operation.

Aperture closing systems as herein described and illustrated form the subject matter of Patent Specification Application No. 14946/80 (Serial No. 1599042) divided from the present Specification.

WHAT WE CLAIM IS: 1. A fire safety system as claimed in Claim 1 of Patent Specification No 1 326 112, wherein said closure means consist of, or include, a movable louvre system.

2. A fire safety system as claimed in Claim 1, wherein said louvre system comprises a first set of pivotally mounted louvre blades arranged, when open, to promote the ingress of air into the building, and a second set of blades arranged, when open, to promote the egress of smoke-laden air from the building.

3. A fire safety system as claimed in Claim 2, including control means for adjusting the angular position of the louvre blades; bias means urging the control means in the direction necessary to rotate the blades into the open position; and locking means effective to hold the control means in the position in which the louvres are closed.

4. A fire safety system as claimed in Claim 3, wherein the pivot axes of said louvre blades are substantially horizontal, wherein the first of said sets of blades occupies the lower part of the aperture, while the second of said sets occupies the upper part of the aperture, and wherein the control means are arranged so that, when said louvre system is open, the blades in said first set slope inwardly and upwardly with respect to said wall, while the blades in said second set slope outwardly and upwardly with respect to said wall.

5. A fire safety system as claimed in Claim 4, wherein said control means are effective to rotate both sets of blades in the same direction from the closed position to the open position, the blades of said first set being rotated through substantially 45 , and the blades in said second set being rotated through substantially 135".

6. A fire safety system as claimed in Claim 5, wherein said control means includes a lever mechanism which causes the blades in said second set to be rotated through an angle of substantially 135 , while the blades in said first set are rotated through an angle of 45".

7. A fire safety system as claimed in Claim 6, wherein said control means includes a pair of slidable shafts, a bracket on each of said louvre blades, means coup ling the brackets on the blades in said first set to a first one of said shafts, and means coupling the brackets on the blades in said second set to a second one of said shafts.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. bracing a portion of one side of the blade and secured thereto by means of adhesive. The channel member includes a shaft 50, a first portion 51 of which is circular, a second portion 52 of which is square, and a third portion 53 of which is threaded to receive a nut 54. The circular portion 51 is rotatable in a hole in a channel member 55 fitted at the side of the closure means, while the square portion 52 engages in a similarly-shaped aperture in the pinnion sector 46. In the embodiment illustrated in Figure 8, the upper louvre system of the previouslydescribed embodiments is replaced by a panel such as that shown in Patent Specification No 1 326 113. The panel is in the form of a glazed sash 60, pivotally mounted in a frame 61. The sash is normally held in the closed position by means of an electromagnet 62 cooperating with an armature plate 63. If the electromagnet 62 is deenergised, the upper portion of the sash is pushed outwardly by means of a spring 64. The pivot axis of the sash is below its center of gravity and, accordingly, once the spring 64 has exerted a pressure on it, it will continue to rotate into the position shown in Figure 8 in which it is retained by means of a bracket 65. The lower louvre system consists of two louvre blades 4 and 5 which are controlled in a manner generally similar to that shown in Figure 6. However, in this case, there is no necessity for any difference in the angle of rotation of the blades and hence a rack 66 of constant width cooperates with two similar pinnions 67 and 68. The rack 66 is normally held in its uppermost position by means of an electromagnet 69 cooperating with an armature plate 70 secured to an arm 71 extending from the shaft 66. The shaft is urged downwardly by means of a spring 72 and can be manually controlled by means of a handle 73. In the embodiment of Figure 8 it will be seen that, in the open position of the system, the panel 60 slopes upwardly and outwardly, while the louvres 4 and 5 slope upwardly and inwardly. Thus, as in the case of the previously-described embodiments, the system promotes the ingress of fresh air and the egress of smoke-laden air. However, in contrast to the previous systems, the panel 60 rotates through only 45". This arrangement is preferred in view of the normally required size and weight of the panel. As previously stated, in a modification of the embodiment shown in Figure 8, the panel 60 is manually openable. In this case, the electromagnet 62 and the armature plate 63 may be replaced by a normal window fastening controlled by a cord or the like extending to a suitable height for operation. Aperture closing systems as herein described and illustrated form the subject matter of Patent Specification Application No. 14946/80 (Serial No. 1599042) divided from the present Specification. WHAT WE CLAIM IS:

1. A fire safety system as claimed in Claim 1 of Patent Specification No 1 326 112, wherein said closure means consist of, or include, a movable louvre system.

8. A fire safety system as claimed in

Claim 7, wherein said two shafts are coupled together by means providing lost motion between them.

9. A fire safety system as claimed in Claim 8, wherein said shafts are urged in the direction necessary to rotate all said blades into the open position by means of springs, and wherein said shafts are adapted to be retained in the position in which said louvre blades are in the closed position by electromagnetic locking means.

10. A fire safety system as claimed in Claim 5, wherein said control means includes a gearing mechanism which causes the blades in said second set to be rotated through an angle of substantially 135 , while the blades in said first set are rotated through an angle of 45".

11. A fire safety system as claimed in Claim 10, wherein said control means includes a first rack cooperating with pinnions mounted on brackets attached to the louvre blades in said first set, and a second rack cooperating with Thanions mounted on brackets attached to the louvre blades of said second set, the gear ratio between the second rack and the pinnions of said second set of blades being substantially three times as great as the gear ratio between the first rack and the pinnions of the first set of blades.

12. A fire safety system as claimed in Claim 11, wherein said first and second racks are formed on a single slidable bar.

13. A fire safety system as claimed in Claim 12, wherein said bar is urged in the direction necessary to open all said louvre blades by spring means, and is adapted to be retained against the action of said spring means in the position in which said louvre blades are closed by electromagnetic locking means.

14. A fire safety system as claimed in Claim 3, wherein said control means are adapted to control said two sets of blades independently, individual bias means and locking means being provided for each set.

15. A fire safety system as claimed in any of the preceding Claims, wherein each louvre blade is mounted to pivot about a horizonal axis located below the center of gravity of that blade.

16. A fire safety system as claimed in any of the preceding Claims, wherein each of said louvre blades consists of glass.

17. A fire safety system as claimed in Claim 1, wherein- said closure means consist of a movable louvre system and a panel which is pivotable about a horizontal axis.

18. A fire safety system as claimed in Claim 17, wherein said louvre system is arranged, when open, to promote the ingress of air, and wherein said panel is arranged, when open, to promote the egress of smoke

19. A fire safety system as claimed in Claim 18, wherein said panel is mounted above said louvre system.

20. A fire safety system as claimed in Claim 19, including control means for adjusting the angular position of the blades and the angular position of said panel, bias means urging the control means in the direction necessary to rotate the blades and the panel into the open positions, and locking means effective to hold the control means in the position in which the louvres and the panel are closed.

21. A fire safety system as claimed in any of Claims 17 to 20, wherein the louvre blades of the louvre system are arranged so that, in the open position of the louvre, the blades slope upwardly and inwardly with respect to said wall of the building, while the panel is arranged so that, when it is open, it slopes upwardly and outwardly.

22. A fire safety system as claimed in Claim 17. wherein said louvre system is automatically opened when smoke is detected, whereas said panel is manually openable.

23. A fire safety system including closure means substantially as hereinbefore described with reference to, and as illustrated in, Figures 1 to 5, Figures 6 and 7, or Figure 8 of the accompanying diagrammatic drawings.