Fire retardant foam generator

A generator for fire retardant foam utilizes a foamable liquid in a fire hose terminating in a nozzle. The generator includes a housing having an inner chamber with a first entrance opening and a second exit opening. A moveable screen is disposed within the housing to aid in the generation of the foam. A connector is also employed for fastening the housing to the fire hose nozzle utilizing a plurality of hingable elements connected to the housing and a clamp for fixing the plurality of elements to the exterior of the fire hose.

BACKGROUND OF THE INVENTION 
The present invention relates to a novel fire retardant foam generator 
usable with a conventional fire hose nozzle. 
Fire extinguishing materials include the use of water, and foam producing 
chemicals. Fire hoses normally deliver water under pressure received from 
a particular utility agency, or pressure provided by a pumping mechanism, 
such as a pumper truck. 
Certain fires classified as class B and class C require extinguishing based 
on principles other than the cooling effect provided by water. For 
example, foam type extinguishing materials spread a layer of foam over 
burning material and extinguishes the fire by excluding oxygen. Similarly, 
fire extinguishing systems employ carbon dioxide, halogen, and the like to 
remove oxygen. 
Foam materials have been applied to wildland types of fires by utilizing 
fire hoses and fire hose nozzles, generally employed with simple water 
delivery in conjunction with foam generating equipment. In this regard, 
U.S. Pat. Nos. 2,774,583 and 3,667,687 describe apparatuses for producing 
foams to fight fires which may be used with or in substitution for nozzles 
employed with large fire hoses.. Attention is also drawn to a foam making 
attachment for fire hose nozzles known as MX-Foamjet manufactured by Task 
Force Tips of Valparaiso, Ind. Prior art devices, however, are difficult 
to adapt to fire hose nozzles of different sizes. Such lack of universal 
fittings and connectors is often fatal during fire emergencies. 
A fire retardant foam generator which is simple to manufacture, use, and 
adapt to existing fire hose nozzles would be a notable advance in the fire 
fighting field. 
SUMMARY OF THE INVENTION 
In accordance with the present invention a novel and useful fire retardant 
foam generator is provided. 
The generator of the present invention utilizes a housing having a chamber 
with a first entrance opening and a second opening for egress. The housing 
may be formed of any rigid or semi-rigid material. A handle portion may be 
provided to extend from the housing. Such handle portion may take the form 
of a ring-shaped member connected to the external wall of the housing. In 
addition, at least one screen may be placed within the housing to disperse 
the foam and water mixture passed into the housing through a fire hose. 
Means may also be included in the present invention for positioning one or 
more screens within the housing at various positions therewithin. Such 
positioning means may take the form of a series of bores through the 
housing which are capable of permitting fasteners to pass through the same 
and engage one or more screens within the housing chamber. Bores which are 
not being employed for this purpose may be easily plugged by unused 
threaded fasteners or other plugs which are easily removable and 
replaceable in such bores. The screens disposed within the housing may 
take various shapes depending on characteristics of the foam generating 
material as well as the velocity of the foam and water stream and the 
like. Such screen shapes would be selected to produce foam streams which 
project various distances and spread at various widths when leaving the 
generator of the present invention. 
Connecting means is also found in the present invention for fastening the 
housing to the fire hose nozzle to permit flow of the foamable liquid from 
the fire hose into and out of the housing for fighting a fire. Such 
connecting means possess a plurality of elements which are hingedly 
attached to the housing at the first opening to the same. Such hingable 
elements may include a first portion forming part of the housing and a 
second flange portion which extends over the fire hose nozzle. The second 
flange portion may also be provided with a sealing element such as an 
elastomeric material to aid in the gripping of the second flange portion 
to the fire hose nozzle. A clamp is employed to fix the connection means 
to the fire hose nozzle such that turning or rotation of the housing, with 
or without the aid of the handle, will also turn the fire hose nozzle and 
adjust the stream of fluid flowing therethrough. 
A shock absorbing element may also be connected to the housing in the 
vicinity of the second opening thereto. Such shock absorbing element may 
be constructed of a ring of elastomeric material. Thus, damage to the 
generator of the present invention is minimized. 
It may be apparent that a novel and useful fire retardant foam generator 
has been described. 
It is therefore an object of the present invention to provide a fire 
retardant foam generator which is capable of being fastened to a 
conventional fire hose for the purpose of foam generation and control of 
the fire hose effluent stream. 
Another object of the present invention is to provide a fire retardant foam 
generator which includes a housing having a chamber with screens that are 
adjustably positioned therewithin to coincide with the flow and pressure 
characteristics of the stream exiting the fire hose nozzle. 
A further object of the present invention is to provide a fire retardant 
foam generator which includes connecting means permitting the generator to 
be attached to fire hose nozzles of different sizes and shapes. 
A further object of the present invention is to provide a fire retardant 
foam generator which may be employed simply and quickly to fight wild 
fires in remote areas. 
The invention possesses other objects and advantages especially as concerns 
particular characteristics and features thereof which will become apparent 
as the specification continues.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Various aspects of the present invention will evolve from the following 
detailed description of the preferred embodiments thereof which should be 
taken in conjunction with the prior described drawings. 
The invention as a whole is depicted in the drawings by reference character 
10. The fire retardant foam generator 10 includes as one of its elements a 
housing 12, FIG. 1, which is provided with a chamber 14 therewithin. 
Housing 12 may be constructed of any rigid or semi-rigid material such as 
metal, plastic, wood, and the like. As depicted in FIG. 1, housing 12 is 
constructed of metallic material and is substantially cylindrical in 
shape. Housing 12 includes a first opening 16 and a second opening 18. 
First opening 16 permits the flow of foamable material from fire hose 20 
via nozzle 22, which will be described in detail hereinafter. Second 
opening 18 is intended to permit the egress of foam retardant material in 
order to fight a fire. Such foam material 24 is depicted in FIG. 1. 
Foamable material is injected into fire hose 20 prior to arrival at nozzle 
20 and generator 10. Such injection is known in the art and has been used 
with prior foam generating devices. 
Housing 12 is provided with screens 26 and 28 which are generally circular 
in shape. Screens 26 and 28 include flanges 30 and 32, respectively, which 
ride on the inner surface 34 of housing 12. Plurality of fasteners 36 are 
capable of passing through plurality of bores 37 which extend through 
housing 12 to chamber 14 therewithin. Plurality of fasteners 36 are shown 
as taking the form of round-headed screws that engage flanges 30 and 32 
having threaded receptors therealong. Of course, other fasteners may be 
employed in this regard such as expandable rings, pins, ties, and the 
like. Fastening means 38 for fixing screens 26 and 28 to housing 12, as 
described above, permit the moving of screens along the interior surface 
34 of chamber 12 to accommodate the particular flow rate and pressure of 
material exiting nozzle 22. In addition, a screen 40 is depicted in 
phantom in FIG. 1 as having a curved or domed- shaped configuration. It 
should be understood that screens found within chamber 14 may take any 
suitable shape necessary to generate foam material 24. Plugs 29 may occupy 
any bores 37 not cooperating with fasteners 36. 
A shock absorbing element 42 is also illustrated in FIG. 1. Element 42 may 
take the form of an elastomeric band 44 which is tightly held to exterior 
surface 44 of housing 12 by compression, gluing, and the like. Shock 
absorbing element 42 is intended to protect generator 10 against droppage 
and mechanical forces inherent in fighting fires, especially in wilderness 
areas. In addition, a handle 46 is connected by z-shaped brackets 48, 50, 
and 52 to exterior surface 44. A multiplicity of fasteners 54 serve to 
mount z-shaped brackets 48, 50, and 52 to ring 56 and the exterior 44 of 
housing 12. Ring 56 is easily grippable by the user of generator 10 to 
hold or twist housing 12. 
Connecting means 58 externalizes in a trio of elements 60, 62, and 64 which 
are hingably attached to exterior surface 44 of housing 12 through hinges 
66, 68, and 70, FIG. 2. Each of the elements 60, 62, and 64 are 
identically constructed in the embodiment shown in FIGS. 1 and 2. By way 
of example, element 60 possesses a first portion 72 which forms a part of 
housing 12. A second flange portion 74 extends outwardly from housing 12 
and includes an elastomeric strip 76, FIGS. 1 and 3. Clamp 78, in the form 
of a cinching band, commonly known as "plumber's tape" holds flange 74 and 
identical flanges from elements 62 and 64 to the exterior of fire hose 
nozzle 22. Clamp 78 exerts sufficient force such that the rotation of 
housing 12 also rotates the fire hose nozzle 22. 
In operation, the user attaches generator 10 to fire hose nozzle 22 by 
employing a clamp 78. Clamp 78 brings together the second flange portions, 
such as flange portion 74 of element 60, of elements 60, 62, and 64. Clamp 
78 is tightened sufficiently to firmly hold elements 60, 62, and 64 to 
nozzle 22 such that housing 12 and nozzle 22 move as a unit. A foamable 
material is passed through hose 20 to nozzle 22 and into housing 12 
chamber 14. Screens 26 and 28 adjustably fastened therein by fastening 
means 38 serve to create foam material 24 exiting generator 10. Where the 
foamable material stream 80 exiting nozzle 22 is of relatively high 
pressure, screens 26 and 28 would be separated at greater distance from 
each other than shown in FIG. 1. On the other hand, a relative low 
pressure effluent 80 from nozzle 22 will require screens 26 and 28 to be 
placed closer to one another than the depiction shown in FIG. 1. Of 
course, screens of various size and shapes may be used within chamber 14, 
such as domed-shaped screen 40 depicted in phantom on FIG. 1. The user of 
generator 10 would grip ring 56 of handle 46 and direct foam material 26 
to a fire. Rotation of housing 12 and nozzle 22 may take place by twisting 
ring 56. Such turning changes the characteristic of the effluent stream 
from nozzle 22. A fog-like stream or to a straight-stream, as well as 
streams exhibiting characterization between such extremes, may flow from 
nozzle 22 by such process. Shock absorbing element 42 would aid in the 
protection of housing 12 from damage during usage in fighting a fire. It 
should be noted that connected means 58 permits the fixing of housing 12 
to fire hose nozzles of different shapes and sizes. It has been found that 
this feature is particularly useful in fire emergencies in remote areas 
that may extend among multiple fire districts where nozzles of different 
sizes may be encountered. 
While in the foregoing, embodiments of the present invention have been set 
forth in considerable detail for the purposes of making a complete 
disclosure of the invention, it may be apparent to those of skill in the 
art that numerous changes may be made in such details without departing 
from the spirit and principles of the invention.