EP4326405A1 - Compressed air foam system provided with an improved mixing system - Google Patents

Compressed air foam system provided with an improved mixing system

Info

Publication number
EP4326405A1
EP4326405A1 EP22719365.3A EP22719365A EP4326405A1 EP 4326405 A1 EP4326405 A1 EP 4326405A1 EP 22719365 A EP22719365 A EP 22719365A EP 4326405 A1 EP4326405 A1 EP 4326405A1
Authority
EP
European Patent Office
Prior art keywords
conduit
compressed air
conduits
pass
foam system
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP22719365.3A
Other languages
German (de)
French (fr)
Inventor
Peter Foeken
Tim HUMMERJOHANN
Simon Rietschel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Iveco Magirus AG
Original Assignee
Iveco Magirus AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Iveco Magirus AG filed Critical Iveco Magirus AG
Publication of EP4326405A1 publication Critical patent/EP4326405A1/en
Pending legal-status Critical Current

Links

Classifications

    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62C—FIRE-FIGHTING
    • A62C5/00—Making of fire-extinguishing materials immediately before use
    • A62C5/02—Making of fire-extinguishing materials immediately before use of foam
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62C—FIRE-FIGHTING
    • A62C27/00—Fire-fighting land vehicles

Definitions

  • the present invention concerns a fire extinguishing system for a firefighting vehicle or device, in particular a compressed air foam system (CAFS) provided with an improved mixing system.
  • CAFS compressed air foam system
  • Firefighting systems e.g. firefighting vehicles or devices
  • fire extinguishing systems configured to supply a fire extinguishing compound to be directed towards a fire in order to lead to its suppression.
  • CAFS compressed air foam systems
  • the water/foam agent solution comprises a foam agent additive dissolved into a great quantity of water, i.e. from 0,5 to 3% or to 8% in volume of additive.
  • the compressed air is mixed to such solution into a mixing chamber module.
  • Such air-solution mixture is at higher pressure with respect to atmospheric pressure and is ejected by an outlet of a pipe directed to the fire, it expands forming a foam which has the properties to extinguish the fire.
  • the air quantity of the foam can be regulated to assume a value comprised between 3 to 20 volume parts of air with respect to liquid solution.
  • such an air/solution ratio comprised between 3 and 10 is defined a "wet foam”
  • an air/solution ratio comprised between 11 and 20 is defined a "dry foam”.
  • one issue related to a CAFS system is to guarantee a correct mixture between the water and the water/foaming solution to provide a suitable air/solution mixture.
  • the air flow and the water flow may vary continuously because the flow or air/solution mixture can be continuously changed by the operator according to the condition of the fire.
  • Such oscillations in water flow may lead to a not satisfactory mixing between water, air and foam agent.
  • water is generally regulated by a butterfly valve, usually closed when the compressed air foam system is engaged, that does not provide a good velocity of the water flow to guarantee a correct mixing between water, foam agent and air.
  • This drawback is particularly present if the requested water flow is low.
  • CAFS system that can provide a good mixing between water, the foam agent and air according to user's necessities.
  • An aim of the present invention is to satisfy the above mentioned needs in a cost-effective and optimized way.
  • FIG. 1 discloses a general schematic representation of a compressed air foam system, CAFS, 1 for a firefighting utility, e.g. a vehicle, not shown.
  • the CAFS 1 essentially comprises a source 2 of water, an air management system 3, a solution dosing system 4 and a mixing chamber 5.
  • the mixing chamber 5 receives water from the source 2, a controlled and defined air flow from air management system 3, an additive agent from solution dosing system 4, e.g. a foam agent and is configured to mix together such elements to provide a suitable flow of firefighting air/solution mixture at an outlet device 6 that may be connected to a pipe used by a fireman.
  • the air management system 3 may be realized in different way, e.g. according to the system described in international patent application PCTIB2020061830 and therefore not further described herein for sake of brevity.
  • solution dosing system 4 may be realized in different known ways. Both the solution dosing system 4 and the air management system 3 are configured to provide respective pressurized fluid flows into mixing chamber 5 of, respectively, foam solution and compressed air.
  • the source 2 of water may be of different typologies such as a water pump, a hydrant, as known in the field.
  • the mixing chamber 5 defines a first inlet 5a fluidly connected to source 2, a second inlet 5b fluidly connected to an output 4a of dosing system 4 , a third inlet 5c fluidly connected to an output 3a of air management system 3 and an outlet 5d fluidly connected to outlet device 6.
  • the mixing chamber 5 comprises an inlet conduit 7, an outlet conduit 8 and a plurality of by-pass conduits 9a, 9b, 9c, 9d fluidly interposed in parallel between inlet conduit 7 and outlet conduit 8.
  • upstream and downstream are used referring to the water path from source 2 to outlet device 6.
  • the inlet conduit 7 is fluidly connected to source 2 from one side and to by-pass conduits 9a, 9b, 9c, 9d, 9e downstream to source 2 while the outlet conduit 8 is fluidly connected to outlet device 8 from one side and to by-pass conduits 9a, 9b, 9c, 9d, 9e upstream to outlet device 6.
  • a first by pass conduit 9a is upstream to a second by-pass conduit 9b that is upstream to a third by pass conduit 9c that is upstream to a fourth by-pass conduit 9d that is upstream to a fifth by-pass conduit that is downstream to only source 2.
  • first by pass conduit 9a is upstream to second by-pass conduit 9b that is upstream to third by pass conduit 9c that is upstream to fourth by-pass conduit 9d that is up stream to fifth by-pass conduit that is upstream to only outlet device 6.
  • output 4a of dosing system 4 and output 3a of air management system 3 are both fluidly connected to only first by-pass conduit 9a, i.e. the by-pass that is most downstream with respect to source 2. More preferably, output 3a of air management system 3 is fluidly connected to first by-pass conduit 9a upstream to outlet conduit 8 and downstream to output 4a of dosing module 4. Dosing module output 4a is fluidly connected to first by-pass conduit 9a downstream to inlet conduit 7.
  • the number of by-pass conduit conduits 9a, 9b, 9c, 9d, 9e is N and the hydraulic diameter of an
  • (M)-th by-bass conduit 9a, 9b, 9c, 9d, 9e) is lower with respect to the (M+l)-th by-bass conduit conduits (9a, 9b, 9c, 9d, 9e), wherein N and M are an integer number and M is smaller than N.
  • the first conduit 9a has a hydraulic diameter that is smaller with respect to second conduit 9b that is smaller with respect to third conduit 9c that is smaller with respect to fourth conduit 9d that is smaller with respect to fifth conduit 9e.
  • inlet and outlet conduit 7 has a hydraulic diameter that is substantially the same as the fifth conduit 9e or greater.
  • outlet conduit 8 has a variable diameter between conduits 9a and 9e.
  • the section of outlet conduit 8 between (M)-th conduit and (M+l)- th conduit has substantially the same diameter of the (M)- th conduit.
  • the section of outlet conduit 8 between b conduits 9a and 9b has substantially the same diameter of conduit 9a
  • the section of outlet conduit 8 between conduits 9b and 9c has substantially the same diameter of conduit 9b
  • the section of outlet conduit 8 between conduits 9c and 9d has substantially the same diameter of conduit 9c
  • the section of outlet conduit 8 between conduits 9d and 9e has substantially the same diameter of conduit 9d
  • the last section has the same diameter of conduit 9e, i.e. the diameter of input conduit 7.
  • at least some among the by-pass conduits 9a, 9b, 9c, 9d, 9e is provided with valve means 10 configured to allow the passage of fluid through the respective by-pass conduit only from inlet conduit 7 towards outlet conduit 8.
  • valve means comprises different pressure control openings thereby allowing to water to flow on the respective by-pass conduit in function of the pressure of water in inlet conduit 7.
  • first by pass conduit 9a i.e. the by-pass conduit directly fluidly connected to air management system 3 and dosing module 4
  • first by-pass conduit 9a is free, i.e. always allows fluid passage from inlet conduit 7 towards outlet conduit 8.
  • first by-pass conduit 9a is not provided with the aforementioned valve means.
  • the other by-pass conduits 9b, 9c, 9d provided with check valve 10 have different opening pressures, i.e. the respective check valves 10 are dimensioned thereby allowing the fluid passage at different pressure levels.
  • the check valve 10a on second by-pass conduit has different opening pressures, i.e. the respective check valves 10 are dimensioned thereby allowing the fluid passage at different pressure levels.
  • valve means 11 configured to be actively controlled to allow the passage of fluid from said inlet conduit 7 to said outlet conduit 8.
  • the fifth by-pass conduit 9e is provided with an electro actuated valve 11, such as an ON-OFF valve, configured to allow or deny the fluid passage from inlet conduit 7 towards outlet conduit 8.
  • an electro actuated valve 11 such as an ON-OFF valve
  • a OAFS 1 The operation of a OAFS 1 according to the present invention and as described above is the following.
  • the water provided by source 2 flows towards inlet conduit 7 and flows to first by-pass conduit 9a.
  • first by-pass conduit 9a In such conduit, that has the smallest hydraulic diameter, increases the velocity of water that is mixed first with foam agent coming from opening 4a and then with compressed air coming from opening 3a. Then it passes to outlet conduit that has a greater diameter and allows a good mixing of the water, at high velocity and premixed with foam agent, with compressed air. Then the mixed solution flows towards outlet device 6.
  • check valve 10a of second by-pass spring opens and allows to the water to pass directly into outlet conduit 8 downstream to second by pass conduit 9b. In this way the solution is furthermore mixed before passing to outlet device 6.
  • water pressure further increases thereby allowing the opening of check valves 10b, 10c of third and fourth by-pass conduits 9c, 9d.
  • valve 11 may be controlled to be opened thereby allowing the passage of water flow mainly in fifth by-pass conduit 9e directly to output device 6. Indeed, only a few amount of water flows through conduits 7, 9a and 8 to mix again into output conduit 8; however, due to diameter difference, the main portion of water passes directly through conduit 9e.
  • CAFS compressed air foam system
  • the proposed mixing module it is possible to mix water with foam solution and air in a very effective way avoiding bad quality foam-solution at outlet device.
  • the mixing module is particularly compact and cost-effective.
  • the mixing module operates in a very wide range of water pressure with the same quality of foam mixture production.
  • the proposed mixing module is versatile and allows production economic of scale.
  • the versatility of the proposed mixing system is clear. Indeed, the mixing system may be used for providing foam solution without air, air-foam solution or simply water to the output device. Accordingly, with respect to known system the mixing system provides all function via a single module.
  • CAFS compressed air foam system

Landscapes

  • Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Nozzles (AREA)
  • Accessories For Mixers (AREA)
  • Fire-Extinguishing By Fire Departments, And Fire-Extinguishing Equipment And Control Thereof (AREA)
  • Drying Of Gases (AREA)

Abstract

Compressed air foam system, CAFS, (1) comprising a source (2) of water, an air management system (3) for providing a compressed air flow, a solution dosing module (4) for providing an additive solution and a mixing chamber module (5) configured to provide an air-solution mixture to an output device (6), the mixing module (5) comprising an outlet conduit (8) fluidly connected to said output device (6) and an inlet conduit (7) fluidly connected to said source (2), the mixing module (5) comprising a plurality of by-pass conduits (9a, 9b, 9c, 9d, 9e) between the inlet conduit (7) and the outlet conduit (8) the by-pass conduits (9a, 9b, 9c, 9d, 9e) having a hydraulic diameter one different with respect to the other and possible valves (10) with related different pressure openings.

Description

"COMPRESSED AIR FOAM SYSTEM PROVIDED WITH AN IMPROVED MIXING
SYSTEM"
Cross-Reference to Related Applications This Patent Application claims priority from Italian
Patent Application No. 102021000010364 filed on April 23, 2021, the entire disclosure of which is incorporated herein by reference.
Technical Field of the Invention The present invention concerns a fire extinguishing system for a firefighting vehicle or device, in particular a compressed air foam system (CAFS) provided with an improved mixing system.
State of the Art Firefighting systems, e.g. firefighting vehicles or devices, are provided with fire extinguishing systems configured to supply a fire extinguishing compound to be directed towards a fire in order to lead to its suppression.
In particular, compressed air foam systems (CAFS) are widely known in the art and are directed to the use a mixture of a preset percentage of compressed air and a water/foam agent solution.
In greater detail, the water/foam agent solution comprises a foam agent additive dissolved into a great quantity of water, i.e. from 0,5 to 3% or to 8% in volume of additive. The compressed air is mixed to such solution into a mixing chamber module.
Such air-solution mixture is at higher pressure with respect to atmospheric pressure and is ejected by an outlet of a pipe directed to the fire, it expands forming a foam which has the properties to extinguish the fire. In particular, the air quantity of the foam can be regulated to assume a value comprised between 3 to 20 volume parts of air with respect to liquid solution. As defined in standard DIN EN 16327, such an air/solution ratio comprised between 3 and 10 is defined a "wet foam", while an air/solution ratio comprised between 11 and 20 is defined a "dry foam".
According to the above, one issue related to a CAFS system is to guarantee a correct mixture between the water and the water/foaming solution to provide a suitable air/solution mixture.
However, the air flow and the water flow may vary continuously because the flow or air/solution mixture can be continuously changed by the operator according to the condition of the fire. Such oscillations in water flow may lead to a not satisfactory mixing between water, air and foam agent.
Indeed, water is generally regulated by a butterfly valve, usually closed when the compressed air foam system is engaged, that does not provide a good velocity of the water flow to guarantee a correct mixing between water, foam agent and air. This drawback is particularly present if the requested water flow is low.
Therefore, the need is felt to provide CAFS system that can provide a good mixing between water, the foam agent and air according to user's necessities.
An aim of the present invention is to satisfy the above mentioned needs in a cost-effective and optimized way.
Subject and Summary of the Invention The aforementioned aim is reached by a compressed air foam systems as claimed in the appended set of claims.
Brief Description of the Drawing For a better understanding of the present invention, a preferred embodiment is described in the following, by way of a non-limiting example, with reference to the attached drawing, figure 1, showing a schematic representation of a compressed air foam system comprising a mixing module according to the invention. Detailed Description of Preferred Embodiments of the
Invention
Figure 1 discloses a general schematic representation of a compressed air foam system, CAFS, 1 for a firefighting utility, e.g. a vehicle, not shown. The CAFS 1 essentially comprises a source 2 of water, an air management system 3, a solution dosing system 4 and a mixing chamber 5. The mixing chamber 5 receives water from the source 2, a controlled and defined air flow from air management system 3, an additive agent from solution dosing system 4, e.g. a foam agent and is configured to mix together such elements to provide a suitable flow of firefighting air/solution mixture at an outlet device 6 that may be connected to a pipe used by a fireman.
The air management system 3 may be realized in different way, e.g. according to the system described in international patent application PCTIB2020061830 and therefore not further described herein for sake of brevity.
Also the solution dosing system 4 may be realized in different known ways. Both the solution dosing system 4 and the air management system 3 are configured to provide respective pressurized fluid flows into mixing chamber 5 of, respectively, foam solution and compressed air.
The source 2 of water may be of different typologies such as a water pump, a hydrant, as known in the field.
Preferably, the mixing chamber 5 defines a first inlet 5a fluidly connected to source 2, a second inlet 5b fluidly connected to an output 4a of dosing system 4 , a third inlet 5c fluidly connected to an output 3a of air management system 3 and an outlet 5d fluidly connected to outlet device 6.
According to the described embodiment, the mixing chamber 5 comprises an inlet conduit 7, an outlet conduit 8 and a plurality of by-pass conduits 9a, 9b, 9c, 9d fluidly interposed in parallel between inlet conduit 7 and outlet conduit 8.
In the following, the terms "upstream" and "downstream" are used referring to the water path from source 2 to outlet device 6.
The inlet conduit 7 is fluidly connected to source 2 from one side and to by-pass conduits 9a, 9b, 9c, 9d, 9e downstream to source 2 while the outlet conduit 8 is fluidly connected to outlet device 8 from one side and to by-pass conduits 9a, 9b, 9c, 9d, 9e upstream to outlet device 6.
In detail, a first by pass conduit 9a is upstream to a second by-pass conduit 9b that is upstream to a third by pass conduit 9c that is upstream to a fourth by-pass conduit 9d that is upstream to a fifth by-pass conduit that is downstream to only source 2. In other words, from outlet device 6 points of view, first by pass conduit 9a is upstream to second by-pass conduit 9b that is upstream to third by pass conduit 9c that is upstream to fourth by-pass conduit 9d that is up stream to fifth by-pass conduit that is upstream to only outlet device 6.
In particular, output 4a of dosing system 4 and output 3a of air management system 3 are both fluidly connected to only first by-pass conduit 9a, i.e. the by-pass that is most downstream with respect to source 2. More preferably, output 3a of air management system 3 is fluidly connected to first by-pass conduit 9a upstream to outlet conduit 8 and downstream to output 4a of dosing module 4. Dosing module output 4a is fluidly connected to first by-pass conduit 9a downstream to inlet conduit 7.
Advantageously, the number of by-pass conduit conduits 9a, 9b, 9c, 9d, 9e is N and the hydraulic diameter of an
(M)-th by-bass conduit 9a, 9b, 9c, 9d, 9e) is lower with respect to the (M+l)-th by-bass conduit conduits (9a, 9b, 9c, 9d, 9e), wherein N and M are an integer number and M is smaller than N.
According to the described embodiment, the first conduit 9a has a hydraulic diameter that is smaller with respect to second conduit 9b that is smaller with respect to third conduit 9c that is smaller with respect to fourth conduit 9d that is smaller with respect to fifth conduit 9e. Preferably, inlet and outlet conduit 7 has a hydraulic diameter that is substantially the same as the fifth conduit 9e or greater. More preferably, outlet conduit 8 has a variable diameter between conduits 9a and 9e. In particular, the section of outlet conduit 8 between (M)-th conduit and (M+l)- th conduit has substantially the same diameter of the (M)- th conduit.
Accordingly, the section of outlet conduit 8 between b conduits 9a and 9b has substantially the same diameter of conduit 9a, the section of outlet conduit 8 between conduits 9b and 9c has substantially the same diameter of conduit 9b, the section of outlet conduit 8 between conduits 9c and 9d has substantially the same diameter of conduit 9c, the section of outlet conduit 8 between conduits 9d and 9e has substantially the same diameter of conduit 9d and then the last section has the same diameter of conduit 9e, i.e. the diameter of input conduit 7. Advantageously, at least some among the by-pass conduits 9a, 9b, 9c, 9d, 9e is provided with valve means 10 configured to allow the passage of fluid through the respective by-pass conduit only from inlet conduit 7 towards outlet conduit 8. In particular such valve means comprises different pressure control openings thereby allowing to water to flow on the respective by-pass conduit in function of the pressure of water in inlet conduit 7.
In particular, in the disclosed example, the first by pass conduit 9a, i.e. the by-pass conduit directly fluidly connected to air management system 3 and dosing module 4, is free, i.e. always allows fluid passage from inlet conduit 7 towards outlet conduit 8. In other words first by-pass conduit 9a is not provided with the aforementioned valve means.
Advantageously, the other by-pass conduits 9b, 9c, 9d provided with check valve 10 have different opening pressures, i.e. the respective check valves 10 are dimensioned thereby allowing the fluid passage at different pressure levels. In detail, the check valve 10a on second by-pass conduit
9b has an opening pressure level that is lower with respect to the check valve 10b on third by-pass conduit 9c that has an opening pressure level that is lower with respect to the check valve 10c on fourth by-pass conduit 9d. Advantageously, one among the by-pass conduits 9a, 9b,
9c, 9d, 9e is provided with valve means 11 configured to be actively controlled to allow the passage of fluid from said inlet conduit 7 to said outlet conduit 8.
In particular, the fifth by-pass conduit 9e is provided with an electro actuated valve 11, such as an ON-OFF valve, configured to allow or deny the fluid passage from inlet conduit 7 towards outlet conduit 8.
The operation of a OAFS 1 according to the present invention and as described above is the following. In general, the water provided by source 2 flows towards inlet conduit 7 and flows to first by-pass conduit 9a. In such conduit, that has the smallest hydraulic diameter, increases the velocity of water that is mixed first with foam agent coming from opening 4a and then with compressed air coming from opening 3a. Then it passes to outlet conduit that has a greater diameter and allows a good mixing of the water, at high velocity and premixed with foam agent, with compressed air. Then the mixed solution flows towards outlet device 6. If the water pressure increased, then check valve 10a of second by-pass spring opens and allows to the water to pass directly into outlet conduit 8 downstream to second by pass conduit 9b. In this way the solution is furthermore mixed before passing to outlet device 6. Similarly occurs if water pressure further increases thereby allowing the opening of check valves 10b, 10c of third and fourth by-pass conduits 9c, 9d.
If the user needs only water, without foam solution and air, then valve 11 may be controlled to be opened thereby allowing the passage of water flow mainly in fifth by-pass conduit 9e directly to output device 6. Indeed, only a few amount of water flows through conduits 7, 9a and 8 to mix again into output conduit 8; however, due to diameter difference, the main portion of water passes directly through conduit 9e.
In view of the foregoing, the advantages of a compressed air foam system, CAFS, 1 according to the invention are apparent.
Thanks to the proposed mixing module it is possible to mix water with foam solution and air in a very effective way avoiding bad quality foam-solution at outlet device.
Moreover, the mixing module is particularly compact and cost-effective.
Furthermore, the mixing module operates in a very wide range of water pressure with the same quality of foam mixture production.
In addition, by varying the number of by-pass conduits it possible vary the water pressure range. Accordingly, the proposed mixing module is versatile and allows production economic of scale.
In particular, the versatility of the proposed mixing system is clear. Indeed, the mixing system may be used for providing foam solution without air, air-foam solution or simply water to the output device. Accordingly, with respect to known system the mixing system provides all function via a single module.
It is clear that modifications can be made to the described compressed air foam system, CAFS, 1 which do not extend beyond the scope of protection defined by the claims. For sake of example, the number of by-pass conduits may vary. Similarly, valve means 10, 11 may be substituted by different typologies of valves having the same opening characteristics.

Claims

1.- Compressed air foam system, CAFS, (1) comprising a source (2) of water, an air management system (3) for providing a compressed air flow, a solution dosing module (4) for providing an additive solution and a mixing chamber module (5) configured to provide an air-solution mixture to an output device (6), said mixing module (5) comprising an outlet conduit (8) fluidly connected to said output device (6) and an inlet conduit (7) fluidly connected to said source (2), said mixing module (5) comprising a plurality of by pass conduits (9a, 9b, 9c, 9d, 9e) between said inlet conduit (7) and said outlet conduit (8) each of said by-pass conduits (9a, 9b, 9c, 9d, 9e) having a hydraulic diameter different with respect to the other, said air management system (3) and said dosing module (4) being fluidly connected to at least one of sais by-pass conduits (9a, 9b, 9c, 9d, 9e), said air-solution mixture being obtainable by said compressed air, said water and said additive solution in said outlet conduit (8).
2.- Compressed air foam system according to claim 1, wherein the number of by-pass conduit conduits (9a, 9b, 9c, 9d, 9e) is N and the hydraulic diameter of the (M)-th by- bass conduit (9a, 9b, 9c, 9d, 9e) is greater than the (M-l)- th by-bass conduit conduits (9a, 9b, 9c, 9d, 9e) , wherein
M is less or equal to N.
3.- Compressed air foam system according to claim 1 or 2, wherein one bypass conduit (9e) has a hydraulic diameter equal or greater with respect to the diameter of said inlet conduit (7).
4.- Compressed air foam system according to claims from 1 to 3, wherein said outlet conduit (8) has a variable diameter between said bypass conduits (9a, 9b, 9c, 9d, 9e), wherein the diameter of a section of said outlet conduit (8) between the (M)-th conduit (9a, 9b, 9c, 9d, 9e) and (M-l)- th conduit(9a, 9b, 9c, 9d, 9e) is equal to the diameter of the (M-l)-th conduit(9a, 9b, 9c, 9d, 9e), wherein N is the number of bypass conduits (9a, 9b, 9c, 9d, 9e) and M is a number less or equal to N.
5.- Compressed air foam system according to any of claims from 1 to 4, wherein said air management system (3) and said dosing module (4) are both fluidly connected to the same bypass conduit (9a).
6.- Compressed air foam system according to any of claims from 1 to 5, wherein said air management system (3) is fluidly connected downstream to said dosing module (4), according to water flow direction.
7.- Compressed air foam system according to any of claims from 1 to 5, wherein at least one of said by-pass conduits (9a, 9b, 9c, 9d, 9e) comprises valve means (10, 11) configured to regulate the passage of water towards said outlet conduit (8).
8.- Compressed air foam system according to claim 7, wherein said valve means comprises a check valve (10a, 10b, 10c) configured to allow passage of fluid only from said inlet conduit (7) to said outlet conduit (8) only when the pressure of water in said inlet conduit (7) overcomes a predetermined value.
9.- Compressed air foam system according to claim 8, wherein the opening pressure of said check valve (10a, 10b, 10c) provided in said bypass conduits (9b, 9c, 9d) are different one with respect to the other.
10.- Compressed air foam system according to any of claims from 7 to 9, wherein said valve means comprise a valve
(11) configured to be actively controlled to allow or deny the passage of fluid through one of said by-pass conduit (9e).
11.- Firefighting vehicle comprising the compressed air foam system as claimed in any of the preceding claims.
EP22719365.3A 2021-04-23 2022-04-21 Compressed air foam system provided with an improved mixing system Pending EP4326405A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT102021000010364A IT202100010364A1 (en) 2021-04-23 2021-04-23 COMPRESSED AIR FOAM SYSTEM PROVIDED WITH AN IMPROVED MIXING SYSTEM
PCT/IB2022/053718 WO2022224178A1 (en) 2021-04-23 2022-04-21 Compressed air foam system provided with an improved mixing system

Publications (1)

Publication Number Publication Date
EP4326405A1 true EP4326405A1 (en) 2024-02-28

Family

ID=76708340

Family Applications (1)

Application Number Title Priority Date Filing Date
EP22719365.3A Pending EP4326405A1 (en) 2021-04-23 2022-04-21 Compressed air foam system provided with an improved mixing system

Country Status (6)

Country Link
EP (1) EP4326405A1 (en)
JP (1) JP2024516167A (en)
CN (1) CN117750998A (en)
CL (1) CL2023003133A1 (en)
IT (1) IT202100010364A1 (en)
WO (1) WO2022224178A1 (en)

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2556239A (en) * 1947-04-01 1951-06-12 Richard L Tuve Foam fire fighting method
GB1044558A (en) * 1964-04-10 1966-10-05 Stang Corp John W Variable spray nozzle
EP1809389A1 (en) * 2004-11-04 2007-07-25 Andrey Leonidovich Dushkin Apparatus for generation of fire extinguishing flow
US8360339B2 (en) * 2008-11-13 2013-01-29 Forced Gas Technologies, Llc Fire suppression apparatus and method for generating foam
GB201020539D0 (en) * 2010-12-03 2011-01-19 Pdx Technologies Ag An improved apparatus for generating mist and foams
US20190030551A1 (en) * 2017-07-28 2019-01-31 Dwight Williams Foam spreading nozzle
CN107952194A (en) * 2017-12-18 2018-04-24 山东宏达科技集团有限公司 A kind of multifunctional fire-fighting truck and mixing jetting big gun using liquid nitrogen as injection power
WO2020061830A1 (en) 2018-09-26 2020-04-02 深圳迈瑞生物医疗电子股份有限公司 Ultrasonic imaging system and probe cable management apparatus

Also Published As

Publication number Publication date
WO2022224178A1 (en) 2022-10-27
JP2024516167A (en) 2024-04-12
CN117750998A (en) 2024-03-22
IT202100010364A1 (en) 2022-10-23
CL2023003133A1 (en) 2024-06-21

Similar Documents

Publication Publication Date Title
CA2685105C (en) Improved compressed air foam technology
AU689082B2 (en) Compressed air foam system
US8002203B2 (en) Fire fighting nozzle and method including pressure regulation, chemical and eduction features
US5411100A (en) Compressed air foam system
US8540120B2 (en) Fluid mixing and delivery system
US20090200045A1 (en) Foam Proportioning System with Low-End Controller
WO2022224178A1 (en) Compressed air foam system provided with an improved mixing system
EP1163931A2 (en) System for automatic self-proportioning of foam concentrate into fire fighting fluid variable flow conduit
US7464766B2 (en) Ranger/hybrid automatic self-metering nozzle, with ratio-selectable and flow meter features
JP7526263B2 (en) CAFS system with improved air management system
KR100541969B1 (en) Automatic foam proportioner with flow rate compensation
US6659187B1 (en) Self metering foam proportioning system
GB2289229A (en) Mixing device for fire-fighting foaming agent uses double venturi
JP6554016B2 (en) Fire extinguisher flow regulator
KR101118501B1 (en) Foam proportioner
CA2423593C (en) Improved fire fighting nozzle and method including pressure regulation, chemical and eduction features
KR100490375B1 (en) Fire protection foam proportioner with constant mixing ratio
US20220401771A1 (en) Admixing system for fire-extinguishing systems and method for operating such an admixing system
SU1644102A2 (en) Apparatus for mixing and dosing foaming agent into water flow of fire-fighting equipment pipeline
RU2798253C1 (en) Mixing system for fire extinguishing installations and method of operation of such mixing system
JP2021186550A (en) Fire extinguishing equipment
AU2000277235A1 (en) Improved fire fighting nozzle and method including pressure regulation, chemical and eduction features
JP2021186551A (en) Fire extinguishing equipment
SU1501001A1 (en) Apparatus for admixing and metering-out foaming agent to water flow in fire-fighting line
AU2018271413A1 (en) Blockage resistant pressure reducing valve for debris laden liquids

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20231020

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)