An Improved Portable Fire-extinguisher.
Year: 1890

page_text: Date of Application, 27th May, 1890-Accepted, 25th Oct., 1890
COMPLETE SPECIFICATION.
An Improved Portable Fire-extinguisher.
I, WILLIAM HENRY FREAR, residing at 476 O Street, North-west, in Washington,
District of Columbia, United States of America, Contractor, do hereby declare the
nature of my invention and in what manner the same is to be performed, to be
particularly pointed out and ascertained in and by the following statement :-
The object of the invention is to provide an extinguishing device embracing a
cylinder, preferably of frangible material, provided with a piston capable of throwing
an extinguishing fluid, which device is also adapted upon occasion to be thrown upon
a fire and broken, and which extinguisher if not so thrown shall be adapted for re-use,
and the invention consists in the construction hereinafter described and pointed out.
In the drawing,
Fig. 1 represents a side elevation partly in section, one position of the piston rod
being indicated by dotted lines.
Fig. 2 is a longitudinal central section of one end of the extinguisher on a larger
scale;
Figs. 3 and 4 are modified details, and
Fig. 5 is a partial section of a modified form of piston, piston packing, nozzle
and plug.
1 indicates a cylinder preferably made of frangible material, such as glass, which
may, if desired be coloured or otherwise ornamented, and may also be provided with
one or more lines 2 of comparative thin material in the wall thereof to facilitate
fracture when thrown upon a burning object. But ordinarily it is desirable when
frangible material is employed to make the cylinder wall as thin as practicable in order
to reduce to a minimum the variations of its internal diameter, and in such case a
cylinder will readily break when thrown upon a hard object without any 'special
provision.
3 indicates a metallic cap having a screw thread or equivalent connection with the
cylinder, and 4 an elastic packing. The cap has a screw threaded neck or collar at 5
to receive a correspondingly threaded extension of a handle 6. The collar is made to
abut against a shoulder provided with a packing 7, and the screw threaded extension
is preferably covered with some material that will prevent the absorption of moisture
and consequent swelling of the wood, of which ordinarily the handle will be composed.
For this purpose thin metal may be spun upon the screw threaded extension, but any
known protecting covering may be substituted, or the handle may be made of material
impervious to water. A wooden handle without such protection might operate with
some success, but would be liable to be inconveniently swollen by moisture.
8 indicates a piston composed of two discs secured together and holding between
them any suitable packing 9, preferably of leather, felt, rubber, or like elastic material
of flexible nature and adapted to prevent the passage of fluids between the piston and
cylinder wall. The disks enclosing the packing can be secured together by screws or
screw bolts, or by fastenings analogous to paper clips, as indicated in Figure 4, or in
any convenient manner that will permit their separation when desired. Preferably
the lower disc is made thicker than the upper, particularly when screw fastenings are
employed to afford sufficient thickness for screw threaded openings, and also to provide
a more extended bearing on the piston rod 10.
These disks are concavo-convex and have similar curvature at all parts so that no
sharp edges are made to bear directly against the packing and the screws, or equiva-
lent fastenings are used at several points between the centre and periphery of the
piston to prevent the springing apart of the disks as is liable to happen when said
disks are only fastened at the centre.
The rod is secured in the handle by screw threads or otherwise and extends through
the piston closely fitting a central opening therein which is packed by the flexible

page_text: disk 9, or in case such disk does not extend to the rod a special packing may
be used.
The lower end of the piston rod is screw threaded or otherwise adapted to receive a
thimble or socket 11 to hold an elastic plug 12. The purpose of this plug or stopper,
which may be made of rubber, cork, wood, or like material is to stop the nozzle 13
formed in the screw cover 14 applied to the discharge end of the cylinder, which cap
is closely fitted on the cylinder end and provided with a packing 15. This cap can be
unscrewed and the socket 11, which has for the purpose a screw thread or equivalent
connection can be removed and fitted with a fresh plug, if desired, and at such time
the piston rod can be withdrawn entirely from the cylinder, and it or a new one can
be re-inserted with either the old or a new piston, as desired.
In Figure 5 is represented on a reduced scale a form of the invention, which
presents some points of superiority. Numeral 1' indicates a cylinder, 10¹ a piston rod,
and 16 spring catches. The piston which is preferably made of glass to avoid corrosion
is provided with a circumferential groove in which is fitted an elastic tubular annulus 91,
which will at all times pack the piston tightly, the elastic air tight tube yielding and
expanding according to the slight inequalities of the cylinder, but always keeping in
close contact with both the cylinder and the piston. 121 denotes an elastic cone
shaped plug secured upon the end of the rod 10 and adapted to close the similarly
shaped nozzle 13. A packing is indicated by 15¹.
The cylinder is intended to hold any suitable extinguishing fluid, such as a mixture
of alum and carbonate of ammonia, and to be kept for immediate use in case of fire.
Normally the piston, piston rod and handle are in the position illustrated in Figure 2,
the stopper 12 at such time filling the nozzle, as indicated by dotted lines in Figure 1,
the cylinder being filled with fluid. To prepare for use it is only nescessary to
disengage the handle from the collar by unscrewing and drawing the piston rod
through the piston so that the spring catches 16 shall engage its rear, and it can be
thrust forward as in a syringe. The springs are secured to the rod in recesses formed
therein so that when the rod is drawn through the piston to make ready for use they
are pressed down into the recesses and offer no appreciable resistance, but immediately
expand upon being withdrawn from the piston in readiness to engage the rear of the
piston when the rod is pushed forward. One or more of these springs may be employed,
preferably two. The form of the springs is not material. They can be secured to the
rod in any well known manner, as by brazing, or by rivets, or they may be formed
integral with the rod itself being suitably tempered and arranged.
As before stated, the extinguisher is adapted for breaking by throwing, in an
appropriate emergency, although such use will be exceptional, it being one of the
objects of the present improvement to provide for adapting the extinguisher to repeated
use, for which it is only necessary to compress the springs 16 and re-insert the piston
rod, and arrange the parts as above described the cylinder being refilled with fluid.
To compress the springs so that the rod can be pushed through the piston pinchers or
other suitable tool may be introduced through the collar 5, or the screw cap 5 may be
removed, as found most convenient.
The construction of the piston provides for renewing the packing should it be
injured by repeated use, or by the long continued influence of the extinguishing fluid.
The packing is a very important element of the device, and if broken or unduly
hardened by long continued use will defeat its object. The stopper 12 is also made
renewable in case it is found defective, or become so. The cylinder can be filled with
fluid by removing the smaller screw cap or the other screw cap and the piston, or a
special opening may be provided in the small cap.
I do not broadly claim either detachable piston rods, or pistons comprising detach-
able disks, but only the particular construction and combination of parts hereinafter
pointed out.
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 TL
1

page_text: the piston, and the piston rod provided with spring catches and with recesses to receive
the same when compressed, the rod and spring being adapted to be drawn through the
piston, substantially as described.
2. The extinguishing device consisting of the cylinder with packed caps, the piston
and piston rod, and the handle having a screw threaded extension integral therewith
to engage a collar in a screw cap, said extension being protected from moisture by a
metallic covering spun or otherwise fitted thereon, substantially as described.
3. The extinguishing device consisting of the cylinder with packed caps, the piston
and piston rod the screw threaded socket with elastic plug, and the handle having a
screw threaded extension integral therewith to engage a collar in a screw cap, said
extension being protected from moisture by a metallic covering spun or otherwise
fitted thereon, substantially as described.
4. The extinguishing device consisting of a cylinder of frangible material having
packed caps, a piston made in detachable parts holding a packing, a rod provided with
spring catches and with recesses therefor, and a movable stopper, substantially as
described.
5. In an extinguishing device the cylinder, the piston having a circumferential
groove, and the tubular packing, substantially as described.
6. In an extinguishing device the cylinder, the piston having a circumferential
groove, and the tubular packing, the conical elastic plug, and the similarly shaped
nozzle, substantially as described.
Dated this-27th day of may lose.
S. S. BROMHEAD,
97, Newgate Street, London, E.C., Patent Agent.
May Losv.
S. S. BROMHEAD,
97, Newgate Street, London, E.C., Patent Agent.