GB2174524A

GB2174524A - Alarms associated with fire extinguishers

Info

Publication number: GB2174524A
Application number: GB08607561A
Authority: GB
Inventors: Keith Johnson
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-04-03
Filing date: 1986-03-26
Publication date: 1986-11-05
Also published as: GB8607561D0

Abstract

The system comprises at least one fire alarm unit comprising an alarm housing (1) having an audible warning device (5), which housing is adapted to support an associated fire extinguisher (9), the extinguisher being removably fitted to the housing in such a manner that its removal automatically activates the audible warning device. For a wall mounted unit, the extinguisher is fitted to the alarm housing by releasable fastening means, such as hook end loop strips (19, 20) spring clips (16), or the like, which act to hold the extinguisher body in such a manner that it preloads an alarm push break switch (7) to its off position. For floor mounting, the alarm housing is conveniently in the form of a box adapted to rest on the floor and to provide a support seat (3), the weight of said extinguisher acting to preload a push-break switch to its off position. <IMAGE>

Description

SPECIFICATION Fire alarm system This invention relates to fire alarm systems.

Particularly in buildings such as offices, shops, hospitals and workshops, and also vessels such as ships, boats and the like, it is usual to provide a wired electrical ring system including fire alarm switches at regular locations. Said fire alarm switches are normally in the form of push-break buttons which are preloaded behind a glass plate so as to be automatically operated when the glass is broken.

When operated a central alarm is set off. Additionally, fire extinguishers are usually provided at regular locations around the building or vessel to enable immediate action to be taken to fight any fire which may occur.

A disadvantage with the usual fire alarm system discussed above is the fact that, because a central alarm is used, it does not indicate the precise location of the fire.

An object of the invention is to provide an alternative fire alarm system comprising at least one fire alarm unit, which system is efficient to operate and will readily identify the location of a fire.

According to this invention, a fire alarm unit comprises at least one alarm housing having an audible warning device, which housing is adapted to support an associated fire extinguisher, said housing and extinguisher being fitted to each other in such a manner that removal of the fire extinguisher activates the audible warning device.

Thus, for a wall mounted extinguisher the housing can be shaped to accommodate the extinguisher, which latter is fitted thereto by releasable fastening means, eg Velcro strips, spring clips or the like, which act to hold the extinguisher body in such a manner that it preloads an alarm push break switch to its off position.

Alternatively, for a floor mounted extinguisher, the alarm housing is conveniently designed to rest on the floor and to provide a support seat for the lower end of the extinguisher, the weight of said extinguisher acting to preload a push-break switch to its off position. Conveniently, the push break switch has a biassed lever which is pushed down onto the seat by the weight of the extinguisher when fitted.

When used in a large building, or vessel, it will be appreciated that the fire alarm system will comprise a number of such alarm housing/extinguisher units, which are provided at regular locations, and if thought desirable, said units could be also wired via an electrical ring system to an external audible alarm and/or connected by a telephone link to the local fire station.

In order that the invention may be readily understood, three embodiments of the fire alarm unit will now be described with reference to the accompanying drawings in which: Figure 1 is a cross-sectional elevation of an alarm housing for a free standing fire extinguisher, Figure 2 is a plan view of the housing of Figure 1, Figure 3 is a cross-sectional view of an alarm housing for one embodiment of a wall mounted extinguisher, Figure 4 is a front elevation of the housing of Figure 3 with its front cover removed, and Figures 5 and 6 are views similar to Figures 3 and 4 of another embodiment of a wall mounted alarm housing.

Referring to Figures 1 and 2, for a free standing extinguisher, the alarm housing 1 comprises a box preferably produced as a forming from plastics, the top surface 2 of which is shaped to provide a seat for the box and an upstanding side part 4 in which is housed a siren 5 powered by a battery pack 6. A push-break switch 7 is mounted adjacent to the seat 3 and has a biased lever 8 extending over part of the seat surface so that when the extinguisher 9 is mounted on the seat 2 the weight of it holds the lever down to maintain the switch in its "off" position. A further push-break switch 10 is also provided and mounted with its biased lever 11 in contact with the floor. The battery pack 6 which may be conveniently fitted in position within the box by Velcro strips 12, may be replaced by a mains rechargeable power pack.

In operation, in the event of a fire, as soon as the extinguisher 9 is lifted from its seat 2 for use, the siren is activated by the switch, thus giving an alarm warning at the point of the fire.

Particularly if the system is to be used in a large building or vessel a number of housing/units would be provided throughout and said units could additionally be wired, via an electrical ring circuit, to a common external audible alarm, and/or a telephone link to the local fire station. In addition, a visual alarm, e.g. a flashing light, could be connected into the circuit of each unit to readily identify the exact location of the fire to persons, such as firemen, attracted towards the vicinity by the audible alarm.

Should the assembly of the fire extinguisher and fire alarm housing be lifted clear of the floor, this will also set off the alarm via the push-break switch 10.

Referring to Figures 3 and 4 the alarm housing 1, preferably produced as a plastics forming, is shaped specifically to provide a central recess 12 for accommodating a wall mounting extinguisher 9. To provide the recess a front cover 13 is provided having shaped, vertically extending, side walls 14 and a floor 15. The extinguisher is mounted in the recess 12 via one or more "Terry" spring clips 16. A push break switch 7 is mounted on the floor 15 and provides a projecting button 17 which is depressed by contact with the bottom of the extinguisher to deactivate the switch. Otherwise, the electrical alarm circuit is equivalent to that described with reference to Figure 2, with a battery, or power pack 6 and siren 5.

Referring to Figures 4 and 5, this embodiment is generally similar to the embodiment of Figures 3 and 4. However, in this embodiment the push break switch 7 is mounted adjacent a side wall 14 as shown and has a biased lever 18 which is held down bythe extinguisher 9, when fitted, to deactivate the switch.

In this embodiment the extinguisher is held in position by mating velcro strips 19 and 20 provided on the extinguisher and within the recess 12 of the cover 13. This has an advantage compared with the "Terry" clip arrangement described in the previous embodiment in that an extinguisher of any suitable diameter can befitted.

Claims

1. Afire alarm unit comprising at least one alarm housing having an audible warning device,which housing is adapted to support an associated fire extinguisher, said housing and extinguisher being fitted to each other in such a manner that removal of the fire extinguisher activates the audible warning device.

2. A fire alarm unit according to Claim 1,adapted for wall mounting, wherein the extinguisher is fitted to the alarm housing by releasable fastening means such as Velcro strips, spring clips, or the like, which act to hold the extinguisher body in such a manner that it preloads an alarm push break switch to its off position.

3. A fire alarm unit according to Claim 1, adapted forfloor mounting, wherein the alarm housing is conveniently in the form of a box adapted to rest on the floor and to provide a support seat for the lower end of the extinguisher, the weight of said extinguisher acting to preload a push-break switch to its off position.

4. A fire alarm unit according to Claim 3, wherein a further push-break switch is provided and is preloaded by contact with the floor so that it will activate the alarm if the alarm housing or complete unit is lifted from the floor.

5. A fire alarm unit according to any one of Claims 1 to 4, wherein an additional visual alarm is provided and adapted to be actuated with the audible alarm.