GB2321011A - Domestic cooker fire suppression system - Google Patents

Abstract

A domestic gas or electric cooking appliance has an integral fire suppression system incorporating a supply of extinguishant, typically foam or an inert gas, a heat detector, shut-off means for the gas or electric supply, battery back-up and an optional alarm. The system can be automatic or could be operated manually by a remote switch. The system is compact and may be fitted into a suit case sized module for incorporation into the appliance.

Description

DOMESTIC COOKER FIRE FIRE SUPPRESSION SYSTEM The invention relates to a domestic cooker fire suppress ion system.

BACKGROUND Domestic cookers, when used incorrectly are the cause of a very high percentage of fires in the home. The fires often occur when items being cooked are left unattended on the heating element of the cooker.

Tackling the fires with the use of fire blankets and extiguishers in the hands of untrained persons can result in serious injury.

concept The system will automatically detect the fire on the cooking range using a low voltage, standard domestic, rate of rise and preset heat detector. It will then isolate the cooker from its energy supply GAS/ELECTRICITY using a signal from the unit to close a gas solenoid or in the case of electric cookers a contactor will open.

The supply turned off the system will then release short bursts of AFFF foam (aquious film forming foam with electrical inhibitor) or an inert gas until the fire is extinguished.

During this opperation an alarm will be sounding to warn the occupants that a fire has broken out.

If the occupant discovers the fire before the detector has brought the system into operation then they can operate the system manually via a remote switch on the outside of the kitchen.

There will also be the facility to connect an external voice transmitting sounder that will alert neighbours to the fire.

If the main electrical supply fails the system will still operate using a rechargeable battery back up system.

The system is extremely compact and will fit inside a suitcase size module underneath the cooker in its standard European base.

All connections to valves and the unit will be made by plug and socket assemblies allowing easy installation in a kit form.

The unit will be self contained with extinguishing cartridges built in.

Example Fig 1 In figure one the system is shown in a schematic diagram.

The heat detector will be on the kitchen roof in a suitable location but not directly over the cooker.

The extinguisher cartridge will be placed inside the control box and it will all be located under the cooker, forming an integral part of the cooking appliance.

Fig 2 This is the wiring diagram for the system and shows how each item interconnects.

Fig 3 This is the sequence of events that take place to extinguish any fires on the range.

SEQUENCE OF EVENTS 1. Fire occurs 2. Temperature rising sets off heat detector 3. Alarm sounds 4. Electricity isolated/gas solenoid closed 5. Valve on extinguisher opens, contents released in short burst of 30 seconds then resets 6. ##### ####### #### ########### ###### ## ####### ##### ###### 7. System will operate automatic or manual 8. Remote switching available 9. All valves on flex and plugs (ease of installation) 10. Safety will not reset until gas ring turned off (pressure proven) 11. Interlock so extinguisher can't operate until gaslelectric isolated 12. Very simpie to install 13. Instailed out of reach of children

KEY TO FIG. 1 A Heat Detector B Manual/Automatic Control Unit C Electrical Control Valve D Discharge Nozzle E Extinguishant Container F Electrically Operated Gas Isolation Valve G Gas/Electric Supply To Cooker

Claims (1)

1. CLAIMS 1 A domestic cooker Fire suppression system designed to become an integral part of a domestic cooker,fitting in a suitcase size module with the extinguishant carried inside the unit located in the standard European cooker base. The system comprises of , gas solenoid valve, heat detector, pressure switch,battery backup discharge assembly and control module, with external sounders as extras.All connections made via plug and socket assemblies providing a kit like installation format. The cooker would be connect as normal the system being integral.

   2 A Fire suppression system as claimed in 1 that will isolate the cooker from its energy supply automatically 3 A Fire suppression system as in 1 and 2 with a gas pressure valve to prevent system reset with gas cooker ring controls left open.

   4 A Domestic cooker fire suppression system that runs on a low voltage 24v supply with rechargeable battery backup derived from a domestic 240v supply.

   5 A Domestic cooker fire suppression system that releases the extinguishing agent in short timed bursts adjustable via timers.

   6 A Domestic cooker fire suppression system as in 5 that can operate both automatically or manually using a remote switch 7 A system as above with the capability of operating an external sounder to warn neighbours of the fire.

   8 A Domestic cooker fire suppress ion system as in 5 6 7 that can be adapted to work with existing cookers,or built into the chasis of new cookers during manufacture.

   9 A system as in 5 6 7 and 8 when using AFFF will prevent fire re ignition due to film over pan contents 10 A Domestic cooker fire suppression system as above with safety system built in to prevent extiguishant being released while cooker energy supply is still connected.

   11 A domestic cooker fire suppression system that operates even when the main supply fails by using a rechargeable battery as a back up.

   12 A Domestic cooker fire suppression system as in all claims above that will operate on gas,electric or oil fired cookers.

   14 A domestic fire suppress ion system designed purely for use with domestic cooking appliances to extinguish fire occuring on them either automatically or manually.