GB2563816A

GB2563816A - Fire extinguisher

Info

Publication number: GB2563816A
Application number: GB1706381.9A
Authority: GB
Inventors: Crawley Tony
Original assignee: Firescape Global Ltd
Current assignee: Firescape Global Ltd
Priority date: 2017-04-21
Filing date: 2017-04-21
Publication date: 2019-01-02
Also published as: GB201706381D0

Abstract

A fire extinguisher 1 comprises a plastic outer shell or bottle 2 and an inner bag 6 disposed inside the bottle and containing a fire extinguishing liquid. A cavity defined by an inner surface of the bottle and the outer surface of the inner bag may be pressurised at between 6 and 12 bar. A spray actuator or valve 16 is disposed at the neck of the bottle and is in fluid communication with the inside of the pressurized bag, such that when the valve is opened, fire extinguishing material is expelled from the inner bag through nozzle 16. In preferred embodiments, the fire extinguishing liquid may include one or more of a phosphate, hydrogen phosphate or dihydrogen phosphate salt, a hydrogen carbonate salt or a sulphate salt.

Description

FIRE EXTINGUISHER

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a fire extinguisher.

BACKGROUND TO THE INVENTION

Metal fire extinguishers are common. In order to withstand the high pressures required inside the fire extinguisher for propelling the fire extinguishing medium contained therein during expulsion, the metal walls of such a fire extinguisher must be rather thick. This results in unwieldy, bulky fire extinguishers. Another problem which may arise in conventional fire extinguishers is that they must be held in a certain orientation in order to operate.

SUMMARY OF THE INVENTION

In order to address the problems outlined above, the present invention provides a fire extinguishing device which is lightweight, and may be used whichever way up it is held. Specifically, this is achieved according to a first aspect of the invention which provides a fire extinguisher including: a plastic outer shell; an inner bag for containing fire extinguishing liquid, located within the plastic outer shell; and a spray actuator arranged to deliver fire extinguishing liquid from the bag and direct it at a fire.

By having a plastic outer shell, fire extinguishers according to the first aspect of the present invention are more lightweight than their metal counterparts.

The fire extinguisher may have any one or, to the extent that they are compatible, any combination of the following optional features.

The inner bag, the plastic outer shell and/or the spray actuator are preferably made from recyclable materials, which have obvious environmental benefits. For example, in preferred embodiments the outer shell is made of a plastic such as PET (polyethylene terephthalate).

In some embodiments, one or both of the plastic outer shell and the inner bag may be transparent, allowing a user to see how much liquid is left in the fire extinguisher. This may inform the need for replacement of the fire extinguisher. It may also highlight any leaks or other damage. The fire extinguisher preferably also includes a lid to cover the spray actuator.

In preferred embodiments, the outer surface of the inner bag and the inner surface of the outer shell define a cavity, and the pressure in this cavity is greater than atmospheric pressure (at sea level, just over 1 bar, 1.01325 to be precise). In order to ensure that the contents of the inner bag may be expelled with force even with the inner bag is almost empty, the pressure inside the cavity is preferably selected so that even when the bag is empty or almost empty (i.e. when the cavity has increased in volume), the pressure in the cavity is still higher than atmospheric pressure. For example, in preferred embodiments the pressure inside the vessel is no less than 6 bar, and no more than 12 bar. This increased pressure around the bag helps to force the fire extinguishing liquid out of the inner bag when the spray actuator is actuated. For example, in some embodiments, the actuator may include a valve which opens upon actuation. In those embodiments, the opening of the valve may expose the inside of the bag to the atmosphere, and the increased pressure in the cavity as defined above forces the fire extinguishing liquid through the opening.

The bag may be made of a flexible material, so that it can crumple as the fire extinguishing liquid is forced out of it. For example the bag may be made of a plastic such as PET.

The bag preferably has a capacity of no less than 300 ml, and more preferable has a capacity no less than 1000 ml.

In preferred embodiments, the inner bag of the fire extinguisher contains fire extinguishing liquid. The fire extinguishing liquid preferably includes water. In addition to water, the fire extinguishing liquid may contain: (a) one or more of a phosphate, hydrogen phosphate or dihydrogen phosphate salt; (b) a hydrogen carbonate salt; and (c) a sulphate salt. Herein, phosphate, hydrogen phosphate and dihydrogen phosphate salts are salts including the anions PO43', HPO42' and H2PO4' respectively. A hydrogen carbonate salt is a salt including the anion HCO3'. A sulphate salt is a salt including the anion SO42'. Such a liquid demonstrates an improved ability to extinguish fires quickly and safely relative to known compositions, and is effective against a range of fire types.

For example, the fire extinguisher may contain diammonium hydrogen phosphate ((NHLLHPCL), ammonium bicarbonate (NH4HCO3) and ammonium sulphate ((NH4)2SO4). Fire extinguishing liquid containing these compounds has been found to be particularly effective at extinguishing fires. In some embodiments, the fire extinguishing liquid may further contain monopropylene glycol (C3H8O2), which allows the fire extinguishing liquid to be used at temperatures as low as -20°C without freezing.

In some embodiments, the fire extinguisher of the first aspect of the invention may be adapted to be wall mounted, and accordingly may include a wall mounting portion, such as a hook or a clip.

In some embodiments, the fire extinguisher may be fitted with a smart module configured to transmit a signal on detection that the fire extinguisher has been moved or used.

Accordingly, the fire extinguisher may include a detector such as a motion detector, or a detector which detects when the actuator has been actuated by a user. The detector may also be arranged to detect that the fire extinguisher has been used by detecting the volume of liquid in the inner bag. The signal is preferably a wireless signal, such as an RF signal, and may be received by a wireless hub located remotely from the fire extinguisher.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described with reference to the drawings, in which:

Fig. 1 shows a schematic diagram of a fire extinguisher according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS

Fig. 1 shows a diagram of a fire extinguisher 1 according to the first aspect of the present invention. The fire extinguisher 1 includes a bottle part 2, which has two wider portions 2a and a waist 2b. At the top of the inside of the bottle 2 is an attachment portion 4, to which the bag 6 is attached. The bag 6 is attached to the attachment portion 4 in an airtight manner, the reason for which is discussed shortly. The outer surface of the bag 6 and the inner surface of the bottle 2 defines a cavity 8. The air inside the cavity 8 is at a higher pressure than atmospheric pressure, for example, it may be at 6 to 12 bar. The pressurized air in the cavity 8 must be contained in order to maintain the high pressure - and it is for this reason that the bag 6 must be attached to the attachment portion 4 in an airtight manner. If the air were able freely to flow out from the cavity 8, it would not be possible to maintain the pressure therein and the fire extinguisher 1 simply would not work. The bottom surface 10 of the bottle 2 is shaped as shown to withstand the pressure inside the cavity 8 without breaking.

At the top of the bottle 2 is an actuation means 14. The actuation means includes actuator 16, sleeve 17 and nozzle 18. In use, depression of the actuator 16 into the sleeve 17 causes a valve (not shown) inside the actuation means 14 to open. When the valve is open, a fluid communication channel is opened between the interior of the bag 6 and the atmosphere. Due to the increased pressure in the cavity 8 outside the bag, the air inside the cavity 8 increases in volume, and in doing so, forces the contents of the bag 6 through the opening in the valve and out of the nozzle 18.

Claims

1. A fire extinguisher including: a plastic outer shell; an inner bag for containing fire extinguishing liquid, located within the plastic outer shell; and a spray actuator arranged to deliver fire extinguishing liquid from the bad and direct it at a fire.

2. A fire extinguisher according to claim 1, wherein one or more of the plastic outer shell, the inner bag and the spray actuator are made of a recyclable materials.

3. A fire extinguisher according to claim 1 or claim 2, wherein the plastic outer shell is made from polyethylene terephthalate.

4. A fire extinguisher according to any one of claims 1 to 3, wherein the plastic outer shell is made from polyethylene terephthalate.

5. A fire extinguisher according to any one of claims 1 to 4, wherein one or both of the plastic outer shell and the inner bag are transparent.

6. A fire extinguisher according to any one of claims 1 to 5, wherein the cavity defined by an inner surface of the plastic outer shell and the outer surface of the inner bag is at a pressure greater than atmospheric pressure.

7. A fire extinguisher according to claim 6, wherein the pressure in the cavity is no less than 6 bar and no more than 12 bar.

8. A fire extinguisher according to any one of claims 1 to 7, wherein the actuator includes a valve arranged to open on actuation of the actuator, to expose the inside of the inner bag to the atmosphere.

9. A fire extinguisher according to any one of claims 1 to 8, wherein the inner bag is made of a flexible material.

10. A fire extinguisher according to any one of claims 1 to 9, wherein the inner bag has a capacity of no less than 300 ml.

11. A fire extinguisher according to claim 10, wherein the inner bag has a capacity of no less than 1000 ml.

12. A fire extinguisher according to any one of claims 1 to 11, wherein the inner bag contains fire extinguishing liquid.

13. A fire extinguisher according to claim 12, wherein the fire extinguishing liquid includes water.

14. A fire extinguisher according to claim 13, wherein the fire extinguishing liquid includes: (a) one or more of a phosphate, hydrogen phosphate or dihydrogen phosphate salt; (b) a hydrogen carbonate salt; and (c) a sulphate salt.

15. A fire extinguisher according to claim 14, wherein the fire extinguishing liquid includes: diammonium hydrogen phosphate ((NHLLHPCL), ammonium bicarbonate (NH4HCO3), and ammonium sulphate ((NHLhSCL).