GB2106385A

GB2106385A - Fire detection and fighting system

Info

Publication number: GB2106385A
Application number: GB8117370A
Authority: GB
Inventors: Gerald Dennis Day; Alfred John Cantwell; James Wendell Browne
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-06-06
Filing date: 1981-06-06
Publication date: 1983-04-13
Also published as: GB2106385B

Abstract

The invention relates to a fire detection and extinguishing appliance having tracked or remote mobility, able to take many forms ranging from permanent wall fixture with single turret to high speed tracked airport appliance to remote controlled forest surveillance appliance with water tanks. The invention is usually comprised of a number of power operated jointed turrets having hydraulically controlled nozzles, said nozzles being able to direct a forceful jet of extinguishing agent into a fire. The turrets are motivated by a swivel head control on the aft end of the turret and located beneath the turret head assembly. A fire detection device is located and protected within the turret head assembly to enable the invention to focus its trajectory into the heart of a fire with the aid of electric and electronic control gear. The whole of the turret head assembly is mounted on a carriage assembly that runs on tracks or is mounted on a variety of controllable tractor units. <IMAGE>

Description

SPECIFICATION Fire detection and fighting system This invention relates to a combined fire detection and extinguishing appliance that has tracked and remote mobility.

The main functions of any automatic fire detection system are to detect a fire, to give a local alarm and to give an alarm to the nearest place from which assistance may be forthcoming.

Automatic fire detection systems are usually fixed installations located on or about the ceiling of a room and these when linked with some form of extinguishing apparatus represent the early stages in fighting a fire. However, in large installations covering many square units of ground area the operation of one detector causes the trigger for the whole of the extinguishing apparatus to act.

So in the area where the fire is rampant damage to goods by fire occurs and in other areas damage by water sprinklers or continuous foam generating plant occurs.

Present day detection systems are usually one of two types, heat sensitive or smoke sensitive.

The heat sensitive type normally employing a bimetal strip as the sensing device, the heart of this invention is also heat sensitive but registers the radiated heat energy and therefore suffers not from the disadvantages of the bi-metal strip.

This invention is able to take many different forms in use ranging from a permanent wall fixture with single turret extinguishers connected directly to a household water supply, to a high speed tracked appliance for use at airports. The large quantity of foam making compound and the mixing equipment carried makes these appliances capable of dealing with major fires involving flammable liquids, blanketing the surface of the liquid creating a barrier between the atmosphere and the heat of the burning vapour. Included in the range are a number of remote moving, tractor units capable of expelling water or dilute chemical solutions that can be fitted with closed circuit television and remotely controlled from a safe distance of the fire centre.These units are particularly useful in patrolling large ground area such as forests and oil terminals and have the ability to be manually over-ridden to allow trained firecrews to tackle the blaze.

By way of example the following description relates to a system to be employed within a large factory or building. The contents of this building separated into two separate groups each requiring a different extinguishing agent to successfully combat a fire. However, it is to be understood that there is no limitation in this regard and still further objects and advantages of this invention will become apparent from a study of the following specifications, taken in connection with the accompanying drawings wherein: Fig. 1 shows the appliance to be used in our example Fig. 2 shows a side elevation of the same Fig. 3 shows a floor plan of our proposed building layout In such an application the best mode contemplated is for an overhead system of piping 13 to carry the extinguishing agents.

To resist corrosion of the piping, air pressure is maintained in the pipes until the appliance 10 breaks the seal 12 ready for the reception of water to the one half of the building containing newsprint and other papers and dry powder to the other half housing computers and other electrical equipment.

Placed at regular and strategic junctions of the piping are a number of early warning sensors 9 on permanent operation. These sensors are of low power requirement registering only the initial temperature rise and then signalling the main fire detection and extinguishing appliance 10 when the local temperature rises above a pre-set level.

The appliance 10 comprises two, three or four power operated jointed turrets 1 each ending in a hydraulically controlled jet or nozzle 2. These nozzles are able to be controlled individually to deiiver a forcible jet of water to beat out the flames or a sprinkling shower of water to dampen the materials in combustion so that water vapour may arise to assist in the extinction of the flames.

Motivation of the turrets is effected by a swivel head control 3 on the aft end of the turret located beneath the main turret head assembly 4.

By reason of the swivel head control 3 the turrets 1 are able to move independently enabling for instance, the inner nozzles to deliver a jet of water to the heart of the fire whilst the outer nozzles can assist by sprinkling water in the local area of Within the turret head assembly 4 is housed the fire detection device 5. The detection device is composed of a number of infra-red sensors 1 5, the usual amount being four. These are placed within a retracting tube 6 in such angularity to have a field of view of approximately two hundred and ten degrees.Upon sensing infra-red emissions from a fire the turret head assembly 4 can rotate to position all four sensors 1 5 of the device 5 until the value of infra-red emissions is balanced on all the sensors 1 5, the tube 6 moves forward to surround the sensors reducing the effective field of view to a minimum of about five degrees focussed on the centre of maximum infra-red emissions.

Linked directly to the infra-red sensors 1 5 are the associated electronic and electrical control gear to direct the position of the turret head assembly 4 and to adjust the trajectory of the turrets 1 to play on the heart of the fire. Also on the more sophisticated appliance, provision is included for the radiation level of emissions from the fire to be analysed and so dictate the type of extinguishing agent to be employed on the fire.

The power requirement for the electronic systems comes from a rechargeable battery 1 6 housed within the turrent head 4 and additional power can be obtained from a water pressure generator 1 7 that also supplies power to the hydraulic system for controlling turret positions, nozzle spray control and the swivel head control.

The balance of the room within the turret head 4 is concerned with an emergency tank 1 8.

Generally because of space limitations the tank contains chemical extinguishing agents of a concentrated nature such that when combined together they can produce a vapour forming liquid or gas which smothers combustion by the exclusion of oxygen and by inhibiting the fire reaction taking place. Such tanks are rechargeable and are used in the event of depletion of water reserves or when human assistance has been forestalled.

The whole of the turret head assembly 4 is mounted on a carriage assembly 7 that runs on an overhead mono-rail 8 and contains the main driving motor 19 and the remote control communications equipment 20.

The principle of the system in operation is; the early warning sensors 9 are on continuous duty and resemble a single element infra-red sensor of the type employed in the fire detection device 5.

Their function is to register a local temperature rise and signal to the main appliance 10. On arrival at the scene of the temperature rise, the appliance 10 monitors the temperature increase and the spread of the fire to be certain that the blaze is either, controlled as a fire in a large bin or uncontrolled and spreading at the start of a blaze.

Once the danger has been identified an alarm is sent to the nearest place from which assistance will be forthcoming and a local alarm is given prior to the turret head 4 selecting a working position and directing the turrets 1 at the necessary trajectory.

In our example the location of the fire would dictate the extinguishing agent to be employed and can be confirmed by an analyser on the more sophisticated appliance.

The valve 11 in the carriage assembly 7 engages with the seal 1 2 in the overhead piping 13 ready for the water supply which is directed to the turrets 1 by a flexible hose 1 4.

Once the risk has been eliminated the appliance 10 switches off the water and remains on standby should any further combustion take place whilst the fire department arrives at the scene of the fire.

Claims

1. An appliance for detecting fires, raising an alarm and extinguishing fires. Such an appliance being provided with one or more jointed turrets communicating with a jet or nozzle at one end and flexible conduit at the other end for the purpose of delivering a variety of extinguishing agents into a fire. Said turrets are supported in a swivel head assembly that houses motive elements that provide the movement both independently and simultaneously of the turrets.The swivel head assembly is supported from a turret head assembly that houses an emergency tank of extinguishing agents and the fire detection device, the usual configuration of said device being four sensing elements disposed with such angularity as to give a forward field of vision of two hundred and ten degrees, this field of view being controllably reduced to position the sensing elements on the centre of the fire by retraction into a tube type shield. Electronic receptors responding to the emissions from the detection devices motivate the swivel head to position the turrets into the correct position for extinguishing the fire.The whole of the turret head assembly is mounted from a carriage that runs on a fixed track, said carriage assembly also allowing the turret head to rotate horizontally through 3600 by means of a circular support bearing holding the turret head and carriage together. The carriage assembly also houses the main driving motor and remote control communication equipment.

2. An appliance as set forth in claim 1 wherein said means in said system providing for detection of a fire is effected by means of an infra-red emission collector directly programming the electronics for motivation of the swivel head assembly and where the carriage assembly is mounted to an un-tracked and remote moving bogie, said bogie providing the power and extinguishing agent to the appliance.

3. An appliance as set forth in claim 1 wherein said means in said system providing for detection of a fire is effected by means of a bi-metal strip having such a form as to provide mechanical movement that can be monitored and interpreted into intelligible electronic signals and where the turret head assembly is fixed directly and permanently to a supply line of extinguishing agent.

4. An appliance as defined in any of the preceding claims in which said detection device is a purely electronic scanning device.