AU712134B2 - Fire extinguishing system - Google Patents

Description

WO 98/09682 PCT/SG97/00041 1 FIRE EXTINGUISHING SYSTEM FIELD OF THE INVENTION The present invention relates to fire extinguishing system. In particular, the present invention pertains to fire extinguishing system for minimizing fire hazards in sensitive areas such as the hood of fuel truck, depository of important documents and etc.

BACKGROUND OF THE INVENTION The fire extinguisher canisters for storing and dispensing fire extinguishing agents are found in almost every corner of commercial buildings and fuel storage facility. While such canisters prevent the proliferation of accidental fires when used properly and promptly, fire hazards in sensitive areas such as the hood of fuel trucks remain a critical concern.

It would be ideal to locate a fire extinguishing system at or in the vicinity of the source of potential fire hazard in order to minimize the proliferation of fire in sensitive areas.

WO 98/09682 PCT/SG97/00041 2 OBJECT OF THE INVENTION It is an object of the present invention to automate a fire extinguishing system which does not require human supervision and intervention when an accidental fire is started.

It is an further object of the present invention to retrofit a fire extinguishing system for sensitive areas without requiring major modification of the area.

It is yet another object of the present invention to deliver fire retardant to sensitive areas efficiently and economically.

SUMMARY OF THE INVENTION The present invention has a storage tank for fire retardant which is connected to a piping system with nozzles for discharging fire retardant efficiently in sensitive areas. A system of tubing for sensing fire in sensitive areas is also connected to a pneumatic actuator and in turn to a valve in the piping system.

The system of tubing triggers the pneumatic actuator when its senses the onset of a fire, thus releasing the valve and allows the fire retardant to be discharged through the nozzles in order to extinguish any fire hazards in sensitive areas automatically.

WO 98/09682 PCT/SG97/00041 BRIEF DESCRIPTION OF THE DRAWING Fig. 1 is a schematic of an embodiment of the present invention.

WO 98/09682 PCT/SG97/00041 4 DESCRIPTION OF THE EMBODIMENT OF THE INVENTION The present invention is a system for extinguishing fire automatically in sensitive areas. In the following description, numerous specific details are set forth such as valves and actuators, etc. in order to provide a thorough understanding of the present invention. It will be obvious to one skilled in the art that the present invention may be practiced without these specific details.

In other instances, well-known parts such as those involved the hood of a fuel delivery truck are not shown in order not to obscure the present invention.

Fig. 1 a schematic of an embodiment of the present invention. System 1 of the present invention comprises a storage tank 5 for storing fire retardant a valve 20 for controlling the discharge of retardant 10 from the tank 5, a system of piping 30 with a plurality of nozzles (not shown) throughout the length of the system, a system of tubing 40 for sensing the existence of fire, and an assembly of pneumatic actuator 50 and pressure regulator 60. In the preferred embodiment of the present invention, the storage tank 5 is a large tank capable of holding fire retardant at pressure of between 200 300 psi. It should be understood by one skilled in the art that a regular fire extinguishing canister can also be used as the storage tank for fire retardant. The storage tank may optionally be fitted with a pressure gauge 15 for displaying the pressure within the tank. The outlet of the tank 5 is connected to the valve with a discharge line 25. As mentioned briefly above, the valve 20 controls the flow of fire retardant from the tank 5 to the piping system Referring again to Fig. 1, the valve 20 is in turn connected to the piping system 30 over another discharge line 35. The piping system 30 is preferably located at or in the vicinity of sensitive areas. For instance, the sensitive WO 98/09682 PCT/SG97/00041 areas of a fuel delivery truck (not shown) is the engine compartment under the hood. According to the present invention, the system of piping with nozzles (not shown) is preferably located around the interior walls of the hood of a fuel delivery truck. The nozzles in the piping system 30 permits efficient delivery of fire retardant to the source of fire hazards automatically without human intervention and supervision. This is in contrast with the present practice of relying on fire extinguishing canisters. Where the fuel delivery truck is involved with a traffic collision or turn over, the driver of the truck will most likely be hurt or injured. As such, it is not realistic to expect the driver to use the fire extinguisher to put out any fire from the hood.

Again in Fig. 1. the system of tubing 40 serves as a means to sense the existence of fire in sensitive areas. In the preferred embodiment of the present invention, a plastic tubing having thin walls serves as an economical sensor for detecting any fire hazards in sensitive areas. When a fire perforate the walls (not shown) of the tubing 40, the pneumatic actuator senses a change in pressure. This in turn releases the valve 20 when the change in pressure exceeds the threshold set by the pressure regulator 60. Such action allows fire retardant to flow through the system of piping 30. Like the system of piping 30, the system of tubing 40 is preferably located at or in the vicinity of sensitive areas. While tubing may serve as sensors for system sophisticated sensors such as carbon dioxide sensors may also be used in place of the plastic tubing and the pressure regulator. In the preferred embodiment of the present invention, a manual discharge valve 55 also connects the storage tank 5 with the piping system 30 in the unlikely event that the valve 20 fails.

WO 98/09682 PCT/SG97/00041 While the present invention has been described particularly with reference to FIG. 1 with emphasis on a system for extinguishing fire automatically in sensitive areas, it should be understood that the figures are for illustration only and should not be taken a limitation on the invention. In addition, it is clear that the system of the present invention has utility in many applications where automatic fire extinguishing is required. It is contemplated that many changes and modifications may be made by one of ordinary skill in the art without departing from the spirit and the scope of the invention as described.

Claims (7)

1. A system for extinguishing fire in sensitive areas, said system comprising: a storage tank for storing fire retardant; at least one valve connecting over a discharge line to said storage tank for controlling flow of fire retardant from said storage tank; a piping system coupled to said valve over another discharge line for discharging fire retardant to location of fire hazard when said valve is released, said piping system further comprising of a plurality of nozzles delivering fire retardant therethrough; and at least one sensor coupled to said valve for sensing the existence of fire in sensitive areas and for activating said valve, whereby fire retardant is delivered to sensitve areas automatically and efficiently.

2. The fire extinguishing system in claim 1 wherein said storage tank is a fire extinguishing canister.

3. The fire extinguishing system in claim 1 wherein said sensor comprises a system of tubing having thin walls.

4. The fire extinguishing system in claim 1 wherein said sensor comprises a plurality of sensors for detecting the change in level of combustible gases.

5. A system for extinguishing fire in sensitive areas, said system comprising: a storage tank for storing fire retardant; at least one valve connecting over a discharge line to said storage tank for controlling flow of fire retardant from said storage tank; a piping system coupled to said valve over another discharge line for discharging fire retardant to location of fire hazard when said valve is released, said piping system further comprising of a plurality of nozzles delivering fire retardant therethrough; at least one pneumatic actuator and one pressure regulator for setting a predetermined threshold in change in pressure for activating said valve; a system of tubing coupled to said actuator and regulator for sensing the existence of fire in sensitive areas and for activating said valve, whereby fire retardant is delivered to sensitve areas automatically and efficiently.

6. The fire extinguishing system in claim 5 wherein said storage tank is a fire extinguishing canister.

7. The fire extinguishing system in claim 5 wherein said sensitive area further comprises the hood of a vehicle.