Apparatus for delivering fire suppression agent to dispensers in a fire suppression system

Abstract

An apparatus for delivering fire suppression agent to a fire suppression system comprises a mixing chamber fluidly connected to a fluid dispenser of the system. A first tank for storing water is fluidly connected to the mixing chamber and contains compressed gas. The tank comprises an actuatable release valve that when actuated causes the gas to force the water into the mixing chamber and then to the dispenser. A second tank for storing a firefighting additive is fluidly connected to the mixing chamber. A shutoff valve is operatively moveable between open and closed conditions. When open, the shutoff valve allows the firefighting additive to flow from the second tank into the mixing chamber to mix with the water to produce fire suppression agent that flows to the dispenser. When closed, the shutoff valve prevents the firefighting additive from flowing from the second tank into the mixing chamber.

Description

APPARATUS FOR DELIVERING FIRE SUPPRESSION AGENT TO DISPENSERS IN A FIRE SUPPRESSION SYSTEMField

[0001] The present invention relates to fire suppression systems. More particularly, the invention relates to an apparatus for delivering fire suppression agent to nozzle networks, sprinklers and other devices used to dispense fire suppression agent onto fires by fire suppression systems.Background

[0002] Fire suppression systems are used in work vehicles and heavy machinery to suppress fires that can ignite due to adverse operating issues. For example, a fire can ignite in a work vehicle due to a fuel leak, electrical failure or overheating of the vehicle’s engine. Fires can also ignite in hydraulics compartments used by a vehicle. A fire suppression system operates by dispensing a fire suppression agent onto a fire which starves the fire of oxygen.

[0003] Fire suppression systems must be periodically tested in order to comply with health and safety regulations and standards. For example, Australian Standard AS5062 requires vehicle-based fire suppression systems used in the Australian mining industry to be tested at least twice per year. Each test is designed to simulate a live performance of the system and results in large quantities of fire suppression agent being expelled onto the ground surrounding the vehicle or machinery. The fire suppression agent typically comprises water mixed with a firefighting additive such as foam concentrate. The additive may contain pollutants that can contaminate the environment. For example, foam-based agents may contain long-chain per-and poly-fluoroalkyl substances (PFAS) which can persist in the environment and lead to health problems in humans.

[0004] The preceding discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the present application.Summary

[0005] According to the present invention, there is provided an apparatus for delivering fire suppression agent to a fire suppression system, the apparatus comprising: a mixing chamber fluidly connected to a dispenser of the fire suppression system, the dispenser being configured to dispense fire suppression agent onto a fire; a first tank for storing water, wherein the first tank is fluidly connected to the mixing chamber and contains compressed gas, and wherein the first tank comprises an actuatable release valve that when actuated causes the gas to force the water into the mixing chamber and then to the dispenser; a second tank for storing a firefighting additive, wherein the second tank is fluidly connected to the mixing chamber; and a shutoff valve that is operatively moveable between an open condition and a closed condition by a user of the apparatus, wherein in the open condition the shutoff valve allows the firefighting additive to flow from the second tank into the mixing chamber to mix with the water to produce fire suppression agent that is caused to flow to the dispenser, and wherein in the closed condition the shutoff valve prevents the firefighting additive from flowing from the second tank into the mixing chamber.

[0006] The shutoff valve may comprise a handle for moving the shutoff valve between the open condition and the closed condition.

[0007] The apparatus may comprise a locking mechanism for locking the shutoff valve in the open condition.

[0008] The locking mechanism may be electrically actuatable.

[0009] The locking mechanism may comprise an electrically actuatable latch member that is configured to be extended and retracted to engage with and release the handle respectively.

[0010] The system may comprise a user interface that indicates to the user whether the shutoff valve is in the open condition or the closed condition.

[0011] The mixing chamber may comprise a passage, wherein the passage receives the water flowing from the first tank to the dispenser, and an inlet that receives the firefighting additive from the second tank, wherein the inlet is arranged such that the water flowing in the passage causes a suction action to suck the firefighting additive into the passage via the inlet.

[0012] The passage may have an internal tube extending partially therethrough for receiving the water into the passage, and wherein the tube has an outlet end that terminates at a location that causes the suction action.

[0013] The location at which the outlet end terminates may be substantially at, or downstream of, the inlet in the passage.

[0014] A hose may be fluidly connected to the passage to carry the water from the passage to the dispenser.

[0015] The hose or passage may comprise a fluid restriction downstream of the inlet to cause the water to flow into the second tank when the release valve is actuated to start the suction action.

[0016] The hose may comprise a section that is less in cross sectional area than that of the passage to provide the fluid restriction. In another example, a cross sectional area of the passage may be less at a section of the passage located downstream of the inlet compared to at the inlet to provide the fluid restriction.

[0017] The actuatable release valve may comprise a cylinder mounted on the first tank for receiving the water into the cylinder, wherein an aperture is provided in a side of the cylinder for allowing the water to flow from the cylinder into the mixing chamber, and a piston slidably disposed in the cylinder for opening and closing the aperture.

[0018] The piston may be held in a position that closes the aperture by gas or liquid pressure maintained by a fire detection device.

[0019] The fire detection device may comprise a tube extending from the cylinder to a fire detection area, wherein the gas pressure is provided by gas in the tube, and wherein the tube is adapted to be melted by heat of a fire causing the gas to be released from the tube to reduce the gas pressure.

[0020] The compressed gas in the first tank may be stored in a region in the first tank that is located above the water.

[0021] The present invention also provides a fire suppression system, comprising: a dispenser for dispensing fire suppression agent onto a fire; a mixing chamber fluidly connected to the dispenser;a fire detection device; a first tank for storing water, wherein the first tank is fluidly connected to the mixing chamber and contains compressed gas, and wherein the first tank comprises an actuatable release valve that when actuated by the fire detection device causes the gas to force the water into the mixing chamber and then to the dispenser; a second tank for storing a firefighting additive, wherein the second tank is fluidly connected to the mixing chamber; and a shutoff valve that is operatively moveable between an open condition and a closed condition by a user of the apparatus, wherein in the open condition the shutoff valve allows the firefighting additive to flow from the second tank into the mixing chamber to mix with the water to produce fire suppression agent that is caused to flow to the dispenser, and wherein in the closed condition the shutoff valve prevents the firefighting additive from flowing from the second tank into the mixing chamber.

[0022] The present invention also provides a vehicle that has the fire suppression system described above installed in the vehicle, wherein the dispenser and the fire detection device of the fire suppression system are disposed in or proximal to an engine or hydraulic compartment of the vehicle.Brief Description of Drawings

[0023] Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings, in which:Figure 1 is a side elevation view of an apparatus for supplying fire suppression agent to a dispenser of a fire suppression system according to an example embodiment of the invention;Figure 2 is a cross sectional side elevation view of an actuatable release valve and mixing chamber included in the apparatus, wherein the release valve is shown in an open condition;Figure 3 is a further cross sectional side elevation view of the actuatable release valve and mixing chamber, wherein the release valve is shown in a closed condition; andFigure 4 is a side elevation of a vehicle that comprises a fire suppression system, wherein the system includes the apparatus depicted in Figures 1 and 2.Description of Embodiments

[0024] Referring to Figures 1 to 3, an example embodiment of the present invention provides an apparatus 10 for delivering fire suppression agent to a dispenser 12 of a fire suppression system. The apparatus 10 comprises a mixing chamber 14 fluidly connected to the dispenser 12. The apparatus 10 also comprises a first tank 16 for storing water, wherein the first tank 16 is fluidly connected to the mixing chamber 14 and contains compressed gas 18. The first tank 16 comprises an actuatable release valve 20 that, when actuated, causes the gas 18 to force the water from the first tank 16 into the mixing chamber 14 and then to the dispenser 12.

[0025] The apparatus 10 also comprises a second tank 22 for storing a quantity of firefighting additive. The second tank 22 is fluidly connected to the mixing chamber 14. A shutoff valve 24 is operatively moveable between an open condition and a closed condition by a user of the apparatus 10. In the open condition, the shutoff valve 24 allows the firefighting additive to flow from the second tank 22 into the mixing chamber 14 to mix with the water to produce fire suppression agent that is caused to flow to the dispenser 12. In the closed condition, the shutoff valve 24 prevents the firefighting additive from flowing from the second tank 22 into the mixing chamber 14. Only the water is, therefore, ableto be expelled from the dispenser 12 when the shutoff valve 24 is in its closed condition.

[0026] More particularly, in the example depicted the gas 18 that is stored in the first tank 16 under pressure is carbon dioxide (CO2). The pressurised gas resides in a region of the first tank 16 that is above the water’s surface. When the release valve 20 is opened, the pressure exerted by the gas 18 on the body of water forces a water / air mixture to flow through a siphon tube 25 in the tank 16 and into the mixing chamber 14. The water stored in the first tank 16 may be pure water or it may be impure water that has one or more substances or materials dissolved or suspended therein. As used herein, the term “water” is intended to have this broad meaning including in the claims.

[0027] In the example depicted, the firefighting additive that is held in the second tank 22 is not stored under pressure. The shutoff valve 24 comprises a handle 26 that allows the user to toggle the shutoff valve 24 manually between its open and closed condition. The position of the handle 26 may be electronically monitored and the system 10 may comprise a user interface that indicates to the user whether the handle 26 is currently open or closed. Other types of mechanisms may be used to toggle the shutoff valve 24 in other examples, including electrically actuatable devices. A hose 28 extends between the second tank 22 and the mixing chamber 14 for carrying the firefighting additive from the second tank 22 into the mixing chamber 14.

[0028] The mixing chamber 14 is configured such that the water flowing rapidly through the chamber 14 causes a suction action on the hose 28. The suction action operates to suck the firefighting additive from the second tank 22 via the hose 28 into the mixing chamber 14 when the shutoff valve 24 is in its open condition. The firefighting additive mixes with the water inside of the mixing chamber 14 to produce the fire suppression agent. This agent is forced under pressure to the dispenser 12 via a further hose 30 that is connected to an outletend of the mixing chamber 14. The dispenser 12 is a fluid dispenser comprising a plurality of nozzles that operate to dispense the fire suppression agent onto a fire. The nozzles may be arranged above and / or around an engine of a vehicle that the fire suppression system is installed in. The dispenser 12 may comprise a sprinkler or other suitable device(s) for directing the fire suppression agent onto a fire in other examples. When the shutoff valve 24 is in its closed condition, the firefighting additive is prevented from entering the mixing chamber 14 and, accordingly, only water is supplied to the dispenser 12.

[0029] In Figure 1 , the handle 26 is shown at a twelve o'clock position that causes the shutoff valve 24 to be open. The handle 26 can be moved counterclockwise to a nine o’clock position to close the shutoff valve 24. The apparatus 10 comprises a locking mechanism 32 for locking the shutoff valve 24 in its open condition. The locking mechanism 32 comprises an actuatable latch member that can be extended and retracted from a housing by an electric linear actuator. When the latch member is extended, the latch member provides an obstruction that prevents the handle 26 from being turned counterclockwise. When the latch member is retracted into its housing, the handle 26 is unobstructed and can be freely turned counterclockwise.

[0030] The release valve 20 comprises a cylinder 34 mounted on an uppermost end of the first tank 16 that receives the water from the tank 16. The cylinder 34 may be releasably connectable onto the tank 16 by a screw thread arrangement. Referring to Figures 2 and 3, the cylinder 34 is hollow and comprises a bore extending longitudinally from a lowermost end of the cylinder 34 through to the uppermost end of the cylinder 34. A piston 36 is slidably disposed in the bore. An aperture 38 is provided in a side of the cylinder 34 in fluid communication with the bore. The mixing chamber 14 is connected to a side of the cylinder 34 adjacent to the aperture 38 such that the mixing chamber 14 can receive water from the aperture 38. The mixing chamber 14 may be releasably connectableonto the side of the cylinder 34 by a screw thread arrangement. The piston 36 can slide between a raised (open) position and a lowered (closed) position. As depicted in Figure 2, when the piston 36 is in its open position, the aperture 38 is unobstructed and allows water that has entered into the bore to flow from the bore into the mixing chamber 14. As depicted in Figure 3, when the piston 36 is in its closed position, the piston 36 blocks the aperture 38 and prevents the water from flowing into the mixing chamber 14. The piston 36 rests on an annular ledge 40 extending about an interior surface of the bore when the piston 36 is in its closed position.

[0031] The apparatus 10 includes a mechanism that automatically causes the piston 36 to move up from its closed position to its open position when a fire has been detected by a fire detection device. In the example depicted, the piston 36 is held in its closed position by gas pressure that is maintained by the fire detection device. More particularly, the fire detection device comprises a tube 42 that is fluidly connected to the bore of the cylinder 34. As depicted in Figure 1 , a section 44 of the tube 42 is located in a fire detection area of the vehicle. For example, the tube section 44 may be located in, or proximal to, the engine or hydraulic compartment of the vehicle. Pressurised nitrogen gas is contained inside the tube 42, including tube section 44. This gas is also present in the region of the cylinder bore that is above the piston 36. Referring to Figure 3, when the piston 36 is in its closed position, the water in the first tank 16 exerts an upward acting force on the underside of the piston 36 by virtue of the pressurised CO2gas in the first tank 16. The pressurised nitrogen gas that is above the piston 36 exerts a counteracting downward acting force on the upper side of the piston 36. The pressure of the nitrogen gas is sufficiently high such that the upward acting force cannot overcome the downward acting force. The piston 36 is, therefore, held in its closed position by the pressurised nitrogen gas and is prevented from rising in the bore. It will be appreciated that the pressurised CO2gas in the first tank 16 acts on a surface area of the water in the first tank 16 thatis larger than the surface area of the upper side of the piston 36 that the pressurised nitrogen gas acts on. The nitrogen gas does not, therefore, need to be maintained at a particularly high pressure in order for the piston 36 to be held closed.

[0032] The tube 42 is made of a meltable material, such as nylon, that can be melted by the heat of a fire burning in the fire detection area. When the tube 42 melts, the nitrogen gas in the tube 42 is released which removes the gas pressure acting downward on the piston 36. The piston 36 is, therefore, allowed to rise in the bore into its open position due to the pressure of the water in the first tank 16, as shown in Figure 2. It is envisaged that the tube 42 may comprise a liquid, rather than gas, and operate in a similar manner.

[0033] In other examples, the apparatus 10 may use other types of mechanisms that cause the piston 36 to move into its open position automatically when a fire has been detected. For example, the piston 36 may be held in its closed position by an electrically actuatable clamp member that is operatively connected to an electric linear heat detector in the fire detection area. This detector may comprise a pair of electrical conductors insulated from each other inside a length of heat sensitive polymer. When the polymer is melted by a fire, the conductors short circuit which causes the clamp member to release its hold on the piston 36.

[0034] The mixing chamber 14 comprises a passage 50 that extends laterally from the aperture 38 of the cylinder 34. The passage 50 receives the water leaving the aperture 38. The hose 30 that supplies the water to the dispenser 12 is attached onto an outermost, outlet end of the passage 50. The mixing chamber 14 also comprises an inlet 52 that hose 28 is connected to. The inlet 52, therefore, receives the firefighting additive from the second tank 22. The firefighting additive mixes with the water in the mixing chamber 14 in a required proportion to create fire suppression agent. This fire suppression agent is forced under pressure to the dispenser 12 where it is expelled to suppress the fire. Theinlet 52 is arranged such that the water that is flowing through the passage 50 from the aperture 38 to hose 30 (i.e. , from left to right in Figures 2 and 3) causes a suction action that sucks the firefighting additive from hose 28 into the passage 50 via the inlet 52.

[0035] The passage 50 has an internal tube 54 that extends partially through the passage 50. An innermost end of the internal tube 54 fluidly interfaces with the aperture 38. The internal tube 54 has an outlet end 56 that terminates in the passage 50. Water from the cylinder bore can enter the internal tube 54 via the aperture 38 and exit the internal tube 54 via the outlet end 56 into the passage 50. The uppermost surface of the internal tube 54 is slightly spaced from the inlet 52 such that firefighting additive entering the passage 50 via the inlet 52 is caused to flow along a short portion of the uppermost surface of the internal tube 54 as the additive makes its way downstream toward the tube 30.

[0036] The outlet end 56 of the internal tube 54 terminates at a location in the passage 50 that causes the suction action to be effective. In the example depicted, the outlet end 56 terminates at a location that is immediately downstream of the inlet 52. In this configuration, a strong and consistent suction action is created that causes the firefighting additive to be sucked into the passage 50 from the inlet 52 effectively. In other embodiments, the outlet end 56 may terminate at a different location in the passage 50 to the one depicted. The exact location will depend on the respective shapes and dimensions of the passage 50 and inlet 52 that are used.

[0037] When the release valve 20 is first opened, the hose 28 that supplies the firefighting additive into the mixing chamber 14 is initially empty. An effective suction action will not start to work unless and until fluid occupies the entire length of the hose 28. To resolve this issue, the cross sectional area of hose 30 is less than the cross sectional area of the passage 50. In this configuration, the hose 30 provides a fluid restriction downstream of the inlet 52 that impedes theflow of fluid from the passage 50 into the hose 30. This fluid restriction causes water that initially flows into the passage 50 to flow up the hose 28 toward the second tank 22. This water eventually enters the second tank 22 and meets with the firefighting additive stored in the tank 22. At this point in time, the hose 28 will contain water along its entire longitudinal length. When this state has been achieved, the water in the passage 50 will be flowing rapidly toward hose 30 and the water contained in hose 28 will be substantially static. Owing to Bernoulli's principle, the pressure of the water moving in the passage 50 will be less than the pressure of the water in hose 28. This pressure differential causes the suction action on the inlet 52 to start which results in the firefighting additive being drawn into the hose 28 from the second tank 22. Eventually, a steady state condition is established wherein the firefighting additive is sucked steadily into the passage 50 at a desired flow rate to mix with the water therein.

[0038] In use, the apparatus 10 can be used in fire suppression systems installed in work vehicles and machinery. For example, Figure 4 depicts the apparatus 10 used in a fire suppression system installed in a dump truck 60 of the type used in the mining industry. The first tank 16 and second tank 22 included in the apparatus 10 are attached onto one side of the truck 60. The dispenser 12 comprises a set of nozzles that are located in an engine compartment of the truck 60. The nozzles 12 are positioned above the engine such that they may dispense foam or water onto the engine. The tube section 44 that forms part of the fire detection means used by the system is also located in the engine compartment.

[0039] To prepare the apparatus 10 for use, water is added to the first tank 16 and a suitable firefighting additive is added to the second tank 22. The firefighting additive may comprise a foam concentrate that contains a mix of fluorocarbon-hydrocarbon surfactants and various stabilisers. Gas is pumped into the first tank 16 to an appropriate pressure to pressurise the water therein.The first tank 16 may comprise a gauge 70 that displays the current gas pressure. To prepare the apparatus 10 for use, the handle 26 of the shutoff valve 24 is turned by the user of the apparatus 10 to open the valve 24. The locking mechanism 32 may then be engaged to lock the handle 26 in its open position. In the event of an engine fire, the tube section 44 is melted by the heat of the fire which causes the release valve 20 to open automatically. The opening of the valve 20 causes the water to be expelled from the second tank 22 and forced under pressure through the mixing chamber 14. The foam concentrate in the first tank 16 is sucked into the mixing chamber 14 by suction action and mixes with the water therein to produce a foam-based fire suppression agent. The foam-based agent is forced under pressure through the hose 30 and expelled from the nozzles 12 onto the fire.

[0040] When the apparatus 10 needs to be tested for routine maintenance, the handle 26 of the shutoff valve 24 is turned by the user to close the valve 24. To perform the test, the release valve 20 is manually triggered by the user causing the water to be flushed from the first tank 16 and expelled from the nozzles 12. The closed valve 24 prevents the firefighting additive from mixing with the water during the test. This advantageously prevents pollutants contained in the additive from entering the surrounding environment. Not using the firefighting additive during the test also advantageously results in less wastage and the second tank 22 does not need to be replenished after the test.

[0041] In the example depicted, because the hose 30 is narrower in cross sectional area than the passage 50, the hose 30 provides a fluid restriction downstream of the inlet 52 that causes the suction action to commence when the release valve 20 opens. In other embodiments, the passage 50 may be dimensioned such that it provides the fluid restriction by itself. For example, the passage 50 may taper in diameter such that its cross sectional area is less toward its downstream end that joins the hose 30 compared to at the inlet 52. Inanother example, the passage 50 may comprise an annular stricture that is located toward its downstream end.

[0042] Furthermore, in embodiments the apparatus 10 may employ methods other than a suction effect for transferring the firefighting additive from the second tank 22 into the mixing chamber 14. For example, in one example, the second tank 22 may be elevated above the mixing chamber 14 such that the firefighting additive can flow into the mixing chamber 14 by gravity when the shutoff valve 24 is open. In another example, the second tank 22 may contain compressed gas that causes the firefighting additive to be forced into the mixing chamber 14 under pressure when the shutoff valve 24 is open.

[0043] In the example depicted, the compressed gas 18 that is stored in the first tank 16 above the water provides the pressure that forces the water out of the tank 16 when the release valve 20 is opened. In other examples, the gas 18 may be stored in a separate canister that is submerged in the water in the tank 16. The apparatus 10 will comprise a mechanism that causes the gas to escape from the canister when the release valve 20 is opened.

[0044] For the purpose of this specification, the word “comprising” means “including but not limited to”, and the word "comprises" has a corresponding meaning. It is to be understood that, if any prior art is referred to herein, such reference does not constitute an admission that the prior art forms a part of the common general knowledge in the art, in Australia or any other country.

[0045] The above embodiments have been described by way of example only and modifications are possible within the scope of the claims that follow.

Claims

Claims1 . An apparatus for delivering fire suppression agent to a fire suppression system, the apparatus comprising: a mixing chamber fluidly connected to a dispenser of the fire suppression system, the dispenser being configured to dispense fire suppression agent onto a fire; a first tank for storing water, wherein the first tank is fluidly connected to the mixing chamber and contains compressed gas, and wherein the first tank comprises an actuatable release valve that when actuated causes the gas to force the water into the mixing chamber and then to the dispenser; a second tank for storing a firefighting additive, wherein the second tank is fluidly connected to the mixing chamber; and a shutoff valve that is operatively moveable between an open condition and a closed condition by a user of the apparatus, wherein in the open condition the shutoff valve allows the firefighting additive to flow from the second tank into the mixing chamber to mix with the water to produce fire suppression agent that is caused to flow to the dispenser, and wherein in the closed condition the shutoff valve prevents the firefighting additive from flowing from the second tank into the mixing chamber.

2. The apparatus according to claim 1 , wherein the shutoff valve comprises a handle for moving the shutoff valve between the open condition and the closed condition.

3. The apparatus according to claim 1 or 2, wherein the apparatus comprises a locking mechanism for locking the shutoff valve in the open condition.

4. The apparatus according to claim 3, wherein the locking mechanism is electrically actuatable.

5. The apparatus according to claim 4, when dependent on claim 2, wherein the locking mechanism comprises an electrically actuatable latch member that is configured to be extended and retracted to engage with and release the handle respectively.

6. The apparatus according to any one of the preceding claims, wherein the system comprises a user interface that indicates to the user whether the shutoff valve is in the open condition or the closed condition.

7. The apparatus according to any one of the preceding claims, wherein the mixing chamber comprises a passage, wherein the passage receives the water flowing from the first tank to the dispenser, and an inlet that receives the firefighting additive from the second tank, wherein the inlet is arranged such that the water flowing in the passage causes a suction action to suck the firefighting additive into the passage via the inlet.

8. The apparatus according to claim 7, wherein the passage has an internal tube extending partially therethrough for receiving the water into the passage, and wherein the tube has an outlet end that terminates at a location that causes the suction action.

9. The apparatus according to claim 8, wherein the location is substantially at or downstream of the inlet in the passage.

10. The apparatus according to any one of claims 7 to 9, wherein a hose is fluidly connected to the passage to carry the water from the passage to the dispenser, and wherein the hose or passage comprises a fluid restriction downstream of the inlet to cause the water to flow into the second tank when the release valve is actuated to start the suction action.11 . The apparatus according to claim 10, wherein the hose comprises a section that is less in cross sectional area than that of the passage to provide the fluid restriction.

12. The apparatus according to claim 10, wherein a cross sectional area of the passage is less at a section of the passage located downstream of the inlet compared to at the inlet to provide the fluid restriction.

13. The apparatus according to any one of the preceding claims, wherein the actuatable release valve comprises a cylinder mounted on the first tank for receiving the water into the cylinder, wherein an aperture is provided in a side of the cylinder for allowing the water to flow from the cylinder into the mixing chamber, and a piston slidably disposed in the cylinder for opening and closing the aperture.

14. The apparatus according to claim 13, wherein the piston is held in a position that closes the aperture by gas or liquid pressure maintained by a fire detection device.

15. The apparatus according to claim 14, wherein the fire detection device comprises a tube extending from the cylinder to a fire detection area, wherein the gas pressure is provided by gas in the tube, and wherein the tube is adapted to be melted by heat of a fire causing the gas to be released from the tube to reduce the gas pressure.

16. The apparatus according to any one of the preceding claims, wherein the compressed gas is stored in a region in the first tank that is located above the water.

17. A fire suppression system, comprising:a dispenser for dispensing fire suppression agent onto a fire; a mixing chamber fluidly connected to the dispenser; a fire detection device; a first tank for storing water, wherein the first tank is fluidly connected to the mixing chamber and contains compressed gas, and wherein the first tank comprises an actuatable release valve that when actuated by the fire detection device causes the gas to force the water into the mixing chamber and then to the dispenser; a second tank for storing a firefighting additive, wherein the second tank is fluidly connected to the mixing chamber; and a shutoff valve that is operatively moveable between an open condition and a closed condition by a user of the apparatus, wherein in the open condition the shutoff valve allows the firefighting additive to flow from the second tank into the mixing chamber to mix with the water to produce fire suppression agent that is caused to flow to the dispenser, and wherein in the closed condition the shutoff valve prevents the firefighting additive from flowing from the second tank into the mixing chamber.

18. A vehicle having the fire suppression system according to claim 17 installed in the vehicle, wherein the dispenser and fire detection device of the system are disposed in or proximal to an engine or hydraulic compartment of the vehicle.

Images