Carbonic Acid Generator for Use in Extinguishing Fire.
Year: 1897

page_text: Date of Application, 4th May, 1897-Accepted, 5th June, 1897
Carbonic Acid Generator for Use in Extinguishing Fire.
I, JACQUES PIERRE DUPALET, of 44 Rue du Louvre, Paris, France, Merchant,
do hereby declare the nature of this invention 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 an arrangement of apparatus designed for extinguishing
fire by furnishing instantaneously at high pressure a considerable volume of carbonic
acid gas mixed with water, which can be projected with great case to a distance of
about from thirty to forty yards on to the seat of the fire. The arrangement
comprises, a cylinder containing water saturated with bicarbonate of soda and a
vessel containing sulphuric acid, which is caused to flow into the solution of
bi-carbonate of soda when it is desired to use the apparatus in such a manuer as to
instantaneously render it capable of being employed in extinguishing a fire.
Our arrangement will be clearly understood from the following description with
reference to the accompanying illustrative drawings in which :-
Fig. illustrates an improved arrangement of apparatus in vertical section;
Fig. 2 is a longitudinal section of a modification of the said apparatus, and
Fig. 3 is a vertical section of tlie apparatus taken on the line 1-2 Fig. 2;
Fig. 4 is a longitudinal section of another modification of the apparatus; and
Fig. 5 is a right hand end view thereof.
In the several figs., the same reference letters indicate the same parts.
In the arrangement illustrated in Fig. 1, the apparatus comprises a generator a
of cylindrical form lined internally with sheet lead b and mounted on feet c so as to
be at a certain height above the ground or floor.
Inside the generator is a stoneware vessel d supported by a collar e provided
with trunnions. This vessel is designed to receive a certain store of sulphuric
acid which is used when it is required to place the apparatus in operation, One of
the trunnions is provided with a bevel wheel g gearing with another bevel wheel
keyed on a vertical shaft i extending through a stuffing box k to the exterior of the
generator, where it is fitted with a hand wheel j, by which means the stoneware
vessel can be tipped when required. In order to hold the vessel d vertical, a plug !
of hardened caoutchouc is provided which can be forced into or withdrawn from the
neck m, when necessary, by means of a screw n fitted with a hand wheel o placed
outside. This screw passes through a plug p. (see Fig. 4), which serves as a fixed
nut and is itself screwed into a collar p' with a caoutchouc joint. The cap p is
unscrewed to fill the vessel d. Above the plug lis a washer l'of flexible caoutchouc
designed to make a joint with the nut-like plug p when the hand wheel o is
unscrewed, so as to close up all passages through which the gas might escape. The
generator has an inlet cock 7 for water which is to be saturated with bicarbonate
of soda previously introduced into the apparatus and which is stored in the
generator in sufficient quantity to saturate several charges of water. A cock r
serves to regulate the water level in the generator and one or more outlet cocks s, t
(see Fig. 5) on each of which is fitted an ordinary fire nozzle u (Fig. 1) with a
certain length of flexible hose v. The cocks comprises an immersion pipe which
extends to the bottom of the apparatus, and projects water and gas, whilst the
cock t projects only carbonic acid which is convenient for example in extinguishing
Price 8d.1

page_text: petroleum. Our apparatus is provided with a safety valve y, a pressure gauge, a
refilling and cleaning closure 1, and a discharge cock or plug 2.
Figs. 2 and 3 of the drawings illustrate an arrangement of our apparatus in which
the generator is arranged horizontally and the vessel d is operated directly by hand
by means of the handwheel j keyed on one of the trunnions f passing through the
stuffing box k.
A basin 3 is designed for dissolving the bicarbonate of soda before it is introduced
into the generator through the cock 4.
In Figs. 4 and 5 of the drawings, there is shown another modification of our
apparatus with a special arrangement of the sulphuric-acid-containing vessel d,
which is placed outside the generator. The casing 5, as also the vessel dare
spherical, and the latter is provided with journals. below its geometrical centre in
such a manner that on screwing up the screw n, an automatic discharge will be
effected if the screw-stop 6 be released.
The sulphuric acid contained in the vessel d falls into a perforated gutter 7 which
distributes it within the generator.
The generators when placed horizontally are slightly inclined towards the
discharge cock 2.
Our system of apparatus arranged as above described, is not under pressure; it
is merely charged and can thus remain for an indefinite period.
In case of fire, the apparatus is placed instantaneously under pressure in the
following manner :-The plug 1 of the sulphuric acid container d is removed by
unscrewing the handwheel 10, then the said container is caused to turn in such a
manner as to mix the acid liquid with the alkaline liquid. The acid is neutralized
and produces a very considerable volume of carbonic acid gas under a great
pressure. The apparatus being then under pressure, it is merely necessary to open
the cocks and to direct the nozzle on to the seat of the fire. The extreme velocity
of the jet does not allow the gas to diffuse in the atmosphere.
If it is required to extinguish petroleum for instance, the cock is used, and in
this way only carbonic acid is exclusively projected on to the seat of the fire. It
is to be understood that the forms, details, accessories; materials, and dimensions of
our system of apparatus may vary without in any way altering the principle of our
invention thereby.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. An arrangement of apparatus for providing instantaneously at a high pressuro
a considerable volume of carbonic acid gas mixed with water, which can be
projected by means of pipe to a considerable distance on to the seat of the fire
comprising a reservoir a containing water saturated with bicarbonate of soda, abovo
which is arranged a sulphuric acid containing vessel d supported by two trunnions
in such a manner that said container can be tipped by means of a handwheel; and
the sulphuric acid caused to fall into the solution of bicarbonate of soda in such a
manner as to instantaneously create pressure within the apparatus by the production
of a very considerable volume of carbonic acid gas, said container d also having a
plug for closing and maintaining it in a position of rest, said plug being removed
when it is desired to use the apparatus, by means of a screw n and of a hand-
wheel o, the whole substantially as herein before described and shown in Fig. 1, of
the accompanying drawings.
=
2. The modification of the apparatus specified in the preceding claim wherein
there is provided a tank or basin for dissolving the bicarbonate of soda before its
introduction into the reservoir through the cock 4, substantially as hereinbefore
described and shown in Figs. 2 and 3 of the accompanying drawings.
3. A modification of the apparatus specified in the preceding claims, wherein a
sulphuric acid container d of spherical form, held by a screw 6, and having its
supporting trunnions below its geometrical centre so that it will tip automatically

page_text: as soon as the plug is removed, the apparatus being also provided with a gutter 7
into which the sulphuric acid falls for distribution within the reservoir, substantially
as herein before described and shown in Figs. 4 and 5 of the accompanying
drawings.
1
11..1007
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.