IMPROVEMENTS IN FIRE EXTINGUISHERS
Year: 1889

page_text: Date of Application, 26th Feb., 1889
Specification Accepted, 25th May, 1889
I, JOSEPH M. MILLER, a citizen of the United States of America, residing a
Chicago, in the County of Cook, and State of Illinois, gentleman, do hereby declare
the nature of my invention for IMPROVEMENTS IN FIRE EXTINGUISHERS, and in
what manner the same is to be performed, to be particularly described and ascertained
in and by the following statement
This invention relates to that class of Fire Extinguishers in which a portable vessel
is charged with a fire extinguishing solution under air-pressure and provided with
means for discharging such fluid 'upon a fire by the force of the contained air-pressure.
Structures of this class have been already provided, in some instances, with an
automatic discharge held normally closed by fusible solder which melts at dangerous
surrounding temperatures and allows the extinguishing-liquid to be sprayed upon the
fire, and, in other instances, with a discharge which can be opened by hand to allow
the liquid to be directed upon a fire; but, with a strong air-pressure operating
continuously in the can, it has been found almost impossible to render it so perfectly
air tight as to enable the initial pressure to he maintained for a long time without
material diminution. In the automatically-discharging cans, no means has been
provided for enabling the air-pressure to be tested from time to time, so that the
proprietor could see whether the apparatus could be relied upon for extinguishing a
fire in the absence of an attendant, nor has such apparatus, so far as I am aware, been
constructed to discharge its contents both automatically and at the will of an
attendant.
The objects of my invention are, first, to render such structures perfectly air-tight
under heavy and long continued internal air-pressures; secondly, to enable the
degree of contained air-pressure in an automatic discharge extinguisher to be
conveniently ascertained, from time to time, in order that the owner may know how
far it can be relied upon to do its work automatically in the absence of an attendant;
and, thirdly, to adapt such structures to be operated both automatically and at will.
To these ends, my invention consists, primarily, in combining the vessel with two
discharge devices, one of which opens automatically through a sufficient increase in
the surrounding temperature, and the other of which can be at any time opened and
closed by hand; and, secondarily, in the sub-combinations and structural improve-
ments more partiularly indicated by the several claims hereto appended.

page_text: nererring to the accompanying drawings, in which similar letters of reference
indicate like parts :-
Fig. 1, is a side elevation partly in section of the entire apparatus.
Fig. 2, a bottom view of the same.
Fig. 3, a side and end view of the hand-discharge device.
Fig. 4, a section and end view of the charging device.
Fig. 5, a section and end view of the automatic discharge device, in its normal
condition; and
Fig. 6, similar views of the same device, the section showing the parts at the
moment of discharge.
In the drawings, C is a can or portable tank, of any preferred form and size, made
of sheet iron, steel or other suitable metal, air-tight, capable of resisting any desired
degree of contained air-pressure without leakage, lined in any suitable way to prevent
corrosion, and provided with an ear, ring or hook c at one end or side, for suspending
it from a cord, nail, or other support. This can is to be filled to about two-thirds of
its capacity with a chemical fire extinguishing solution of any approved kind, and is
then, by means of any suitable apparatus, to be charged with a sufficient quantity of
air, under strong pressure, to force its liquid contents out and project them to a
considerable distance, when any of the discharge-ports are opened.
The charging device is represented at D; the automatic discharge device at A; and
the hand-discharge device at B. For the best results, all three of the said devices are
arranged at the end or side opposite to that at which the ear or ring c is applied, so
that all the passages through which escape of air is ever possible shall be covered and
sealed by the contained liquid when the can is in its normal position. For the purpose
of the main combination, the two devices A, B may be of any suitable construction,
and it is immaterial that they are separate from each other or arranged at different
points. But in each of said devices as well as in the device D, the passage or port
must be normally closed with a valve of soft rubber, or other equivalent soft, flexible,
elastic material, impervious to air, and not liable to corrosion from the chemical
solutions contained in the vessel, and such valve must be forced strongly against its
seat and locked or otherwise held there, so that it cannot unseat except for the
performance of its appropriate functions. Each of the valved passages, wherever
possible, is further guarded by an additional screw-plug, or soldered cap, or both.
The conjoint effect of these several provisions is, to render the vessel so absolutely
air-tight that its internal pressure is maintained undiminished for any length of time,
and it is always in condition for effective use.
The specific construction of the several devices, A, B, D, employed by me, is as
follows:-
Referring to the filling device, D, I construct this in the form of a metallic tube or
capsule, d, the inner end of which is closed by a perforated plate d' upon which rests
a soft, elastic, flexible valve d², secured to the plate d¹, at its center, by a pin d³, and
provided with a central plate d*, held to it by said pin, so as to re-inforce the center
of the valve and leave only its edges flexible. The pin d³ is passed through the
plates d d and is provided with a head or enlargement at each end, or it may be
secured to plate d and provided with a head or enlargement on its lower end. This
valve, which acts as a check-valve, will yield for the admission of the air or charging
gas under pressure, through the tube d, but, under the back pressure of the air so
admitted, will seat firmly upon the end plate d', preventing any escape backwards.
For additional security, however, I close the outer end of the tube d, with a close
fitting screw cap d provided with a lead or soft metal seat d' into or against which the
end of the tube d is passed. There is no possibility of the escape of air or liquid
through the device when so constructed. The tube d is soldered or brazed into the
bottom of the can.
Referring to the automatic-discharge device A, I construct this in the form of a
shouldered tube soldered or brazed into the bottom of the can, and provided with an
internal flange a¹ at its inner end. Within this tube, I arrange a sliding tube a²,
having at its lower end a perforated rose-head a³, or a deflector of any approved form.

page_text: and at its upper end an external flange a to prevent its escape from the tube a. In
the larger outer end of the tube a, I insert a thick close fitting disc a³ of soft, flexible,
elastic material, which seats air-tight up against the internal shoulder, a, of said tube;
and I provide a plug or cap a' which is inserted into the outer end of the tube, pressed
firmly up against the disc a so as to hold the latter tightly against its seat, and
soldered to the tube a with fusible-alloy solder melting, preferably, at about
155° Fahrenheit. The valve as keeps the liquid away from the fusible-solder joint and
prevents any chilling of the latter until the cap has been entirely discharged from the
tube, and by its elastic force it aids the internal pressure (which acts through the
sliding rose-head a³) in forcing the cap out of the tube when the solder melts. When
the valve and cap are out, the sliding rose-head a³, projects from the outer end of
tube a.
Referring to the hand discharge B, I first solder or braze into the can a tubular
metal plug, b, provided with screw threads. Into this, I insert a tubular discharge
stem 6 the inner end of which preferably reaches nearly to the opposite side of the
can, as shown in Fig. 1, and attach this tube to the plug b by means of threads 6²,
which screw into the threads of the former. I screw the shoulder, 6³ up against the
end of the plug b, and cover the joint with solder so as to prevent any escape of air at
that point. The outer end of the tube b¹ is enlarged, and a portion of it cut away to
accommodate a swinging block 64 which is pivoted to the main stem at 65, and is
provided with a swinging link or strap 6, carrying a set screw 67, by which to lock
and tighten up the block against the body of the discharge-device, as shown in
Figs. 1 and 3. The inner end of the block 64 inclines preferably at an angle of 45°,
and is provided with a plate or block of soft rubber 68, secured to it by a strip of thin
metal 6º perforated to expose the rubber, or the latter may be secured by cement or
other suitable means, which rubber plate fits air-tight against an inclined shoulder 610
upon the tube 61 when the block is locked in the position shown in Fig. 3. The
central bore of the stem ³ contracts to a discharge nozzle at this point, as shown in
dotted lines in Fig. 3, so as to be opened when the block is released, as shown in
dotted lines in Fig. 1, and closed air-tight at all other times.
This improved structure, as a whole, is designed to be suspended, at a proper
elevation and position, in the room to be protected, where, in the absence of an
attendant, it will operate automatically to spray water upon any accidental fire, in
consequence of the melting of the fusible-solder by the rise of temperature occasioned
thereby. It is also adapted, in case the fire occurs when the attendant is near, to be
conveyed to the immediate neighbourhood of the fire, and opened by hand to direct
the extinguishing liquid in a conncentrated stream upon the exact point where it is
most needed, and thus extinguish the fire inore quickly than could be done by spraying
the rose-head, and with greater economy of the chemical solution. The hand-
discharge, B, can be opened and closed very quickly, from which results the great
advantage that it can be used at any time as a pet-cock to test the degree of effective
pressure in the can, in case a suspicion should arise that it has not been properly filled
or that leakage of air has occurred; thus enabling the proprietor to inform himself, at
any time, of the exact extent to which he can rely upon his fire-extinguisher for
protection and to remedy any defective pressure in season in which respect, this part
of the structure acts as the practical equivalent of a pressure-gauge, but is much
cheaper and less liable to become accidentally damaged. The stem 6' is preferably
extended across nearly to the opposite side of the can, so that, in case the operator
should desire to elevate the hand-discharge nozzle to give the discharging stream a
greater range, the liquid will cover the end of the tube until it is substantially
exhausted from the can.
The inner end of the stem b₁ of the discharge tube is formed or provided with a
series of perforations and its end is preferably closed by a perforated cap, whereby the
formation of a vortex within the can and the escape of air is prevented while the liquid
is being discharged.
A separate charging nozzle provided with a check valve and cap may be provided
through which the liquid may be poured into the can.

page_text: Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is:
1. The combination with a portable fire extinguisher consisting, essentially, of an
air-tight receptacle or can containing a fire extinguishing liquid and air or gas
maintained under pressure and provided with a discharge valve adapted to be operated
by hand, of a supplemental discharge valve applied at or near the base of the can and
adapted to be released by an increase in temperature, whereby said receptacle is
adapted for use as a portable extinguisher or as a stationary extinguisher by
suspending it over or near the place to be protected, the hand operated valve serving
a double purpose to discharge the contents and test the pressure; substantially as
described.
2. In a fire extinguisher, such as described, the combination with the tube b¹
containing the discharge orifice, the block 6* carrying the packing or valve and the
link to which the fastening for engaging the tube is attached, said block 6* being
pivotally attached to the tube and swinging down to clear the discharge orifice when
the link is disengaged from the tube; substantially as described.
3. In a fire extinguisher, the combination of the shouldered tube a with a sliding
internal tube a² provided with a spraying device at its outer end, and with a short
elastic block or disc a³ which closes the tube a and against which said spraying device
normally rests; substantially as described.
4. In a fire extinguisher, the combination of the discharge tube b¹ with the rubber
valve 68 the pivoted block 6 for forcing the valve to its seat, the freely swinging link 66
and the set screw b for tightening the pressure upon the valve while permitting of its
rapid opening, substantially as described.
5. The combination, to form a portable fire extinguisher such as described, of an
air-tight can or receptacle provided with inlet and two outlet orifices the one closed by
a hand operated valve and the other by an automatic valve released by an increase in
temperature, all of said orifices being located at or near the base of the can or
receptacle which latter is charged with a fire extinguishing liquid and a volume of air
or gas under pressure, whereby, all the orifices being below the liquid, the escape of
air or gas is prevented and should the orifices be imperfectly closed the liquid in
escaping will indicate the fact that the apparatus is not in perfect order and requires
attention.
6. In a portable fire extinguisher, the combination with a can containing a fire
extinguishing liquid and a charge of compressed air, of a horizontally disposed
discharge tube provided with a series of perforations through its wall within the can,
substantially as and for the purpose set forth.
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