Dynamite or like High Explosive Materials.
Year: 1886

page_text: Dynamite or like High Explosive Materials.
I, THOMAS STEAD, of the Langham Hotel, Portland Place, London, Gentleman,
do hereby declare the nature of this invention, a communication to me from abroad
by Daniel Moore of 436 Gates Avenue, Brooklyn, New York, United States,
Manufacturer, 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 guns for discharging projectiles containing dynamite or
like high explosive materials, and consists in so constructing a gun that an
extension of material rearward from the breech, proper, of the gun, contains an
air-cushion, a piston fitted therein, a piston rod, at its upper end provided with a
head (fitted to the bore of the gun) against which abuts a wad and the powder
charge, over which another wad is placed, upon which rests, or abuts the projectile.
The object of this invention is to, produce a yielding breech piece, whereby, on the
explosion of the powder charge the piston will be forced downward in the air
cushion chamber until the air in the cushion chamber, has become gradually and
sufficiently compressed, to cause the projectile to gradually move forward, thus
preventing premature explosion of the dynamite (contained therein) within the gun,
also greatly reducing the strain on the gun caused by the sudden expansion of the
gas generated by the ignition of the powder charge.
It has been practically demonstrated that a projectile charged with dynamite
cannot be discharged with safety from a gun constructed with the usual solid
breech, by means of ordinary gun powder; and various devices heretofore have
been applied to such description of guns with a view of counteracting the shock on
the projectile caused by sudden expansion of the gas generated by ignition of the
powder charge, also that guns operated by pneumatic force have been made for a
similar purpose, but all such devices, and pneumatic guns, have failed to produce
the desired results.
By my invention, devices, and arrangement of the parts hereinafter fully
described these difficulties are removed, and the desired results attained.
Others skilled in the art may make and use my invention by reference to the
devices shown in the drawings accompanying this specification and forming a part
thereof in which-
Figure 1 is a vertical central longitudinal section of a gun, illustrating the form
of the gun, and the devices constituting my invention contained therein, a, is the

page_text: gun, b the projectile, c the powder charge, d and d¹ the wads, d' d³ metallic disks,
e the air-cushion cylinder, f the piston, f¹ the piston rod, f the piston rod head,
f³ the cupped elastic wad, f the metallic disk (covering wad f³) f³ the screw pin,
binding f and f' to the piston f, g the reinforce cap, h the rearward extending
stud, h¹ the air charging aperture, i the air chamber, j the auxiliary air chamber,
the air chamber stop cock, n the space to contain the dynamite cartridge, m the
vent. Similar letters refer to similar parts in the several drawings.
Fig. 2 is a modification of Fig. 1, also illustrating the employment therewith of
an air cushion, "Sabot" P, placed between the powder charge, and the projectile,
in this case, the Sabot P, passes out of the gun, with the projectile, when the gun
is discharged.
Fig. 3 is also a modification of Fig. 1 illustrating the utilization of the lower
portion of the bore of the gun as an air chamber, in which is fitted the piston f,
the piston rod f¹ passing through the breech of the gun, and provided with a
retaining cap L.
The manner of construction, combination and operation of the parts as shown
in Fig. 1 is as follows:
>
The parts being made of any suitable material, the air cushion cylinder e, is
provided with screw threads around its periphery, which take into like screw
threads made on the inner surface of the aperture of the extension of the breech,
and is screwed therein. The piston f, piston rod f¹, piston rod head f², air
cylinder cap e, and expanding wad f³, are all combined before the air cushion
cylinder e, is screwed into the breech extension, in the following manner.
The
face of the piston f, has screwed to it by means of the screw pin f, the expanding
disk f³, made of elastic material, (fitted snugly in the air chamber') and the
metallic disk f; this metallic disk f^, is a very little less in diameter than the
closely fitted elastic disk f³, the cap e¹ has an aperture through its centre, through
which the piston rod f¹, is passed, and the piston rod head f', is then screwed
into it; the piston f, is then passed into the air cushion cylinder e, and the
cylinder cap e¹, screwed therein; thus attaching the parts composing the air cushion
together; the cushion, is then screwed in position in the gun. The reinforce cap g,
is then attached to the breech extension, by means of screw threads as shown.
Through this reinforce cap g, is an aperture, through which passes the rearward
extending stud h, (of the air cushion) through which is a small aperture h, to
admit the air into the air cushion chamber; the rear end of this stud h, has screw
threads for attaching the tube of an air pump, and a stop cock k, is provided to
close the apertures h¹.
The parts being in position as shown in Fig. 1 the tube of an air pump is
attached to the stud h, the stop cock kc, turned so as to admit air through its
opening, and the air pump set in motion until the desired amount of compressed
air has passed into the space i, the piston f, being thus forced up until arrested by
the cap el the stop cock k, is then turned so as to close the aperture ¹.
The tube of the air pump may then be detached; the wad d, placed on the piston
rod head, f, the powder placed thereon; the wad d³, placed over it, and the
projectile set against the wad.
11
On ignition of the powder charge c, the operation of the parts or devices will be
as follows: The piston f, piston rod f¹, and its head f³, and wad d, with its
metallic disk da, will be forced downward, gradually compressing the air within
the chamber space i, and the auxiliary chamber space j; the resisting force of the
compressed air gradually increasing, and thus gradually overcoming the inertia of
the projectile b, relieves it, from sudden shock. The compression of the air in the
air chamber space i, as the piston f, descends will cause great pressure against
the metallic disk f', which will cause the cupped face elastic wad f³ to expand
laterally, so as to prevent a possible escape of air from around the closely fitted
piston f. A lateral expansion of the elastic wad d, is caused by pressure of
the powder charge gas acting upon the metallic faced disk d', thus preventing
any escape of air from the auxiliary chamber space at the same time the g
"""
gas.

page_text: generated by the powder explosion acts against the metallic faced disk d³, and
thus compressing and expanding laterally the elastic wad d', prevents the escape
of gas around the projectile b, which abuts on the wad d¹.
In the modification Fig. 2, is shown an air cushion Sabot P, placed between the
powder charge c and the projectile b, in addition to the devices as shown in
Fig. 1, thus affording (if required) a double security against sudden shock of the
projectile, when the discharge takes place (the sabot P passing out with the
projectile b).
The device for admitting air, and retaining it within the air chamber i, consists
of a threaded screw pin h, screwed into a recess provided with like screw threads,
made in the bottom of the air cushion e, said recess having at its bottom a portion
of the metal left, through which a small aperture is made which admits air into
the space i, when the point of the screw h, is raised from off it, but which is
closed when the point of the screw h, is screwed down, as the aperture h², is not
then brought opposite to the aperture in the bottom of its seat.
A mortar for throwing bombs filled with high explosive material, may be con-
structed on the same principles (as shown in Fig. 1) by extending sufficient metal
rearward beyond the line of its trunnions, to contain an air cushion.
The devices as herein shown for a muzzle loading gun can be successfully
applied to a breech loading gun.
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. A gun, constructed with an extension rearward from the breech, proper, of
metal sufficient to receive therein an air cushion, and permit the powder charge
to he placed in a proper position within the gun, substantially as shown and
described.
2. The gun a, constructed as described, in combination with an air cushion,
composed of the air cushion cylinder e, cap e¹, stud h, stop cock k, piston f, piston
rod f¹, and reinforce cap g, substantially as and for the purposes set forth.
3. The air cushion cylinder c, provided with an air charging orifice, an air
charging orifice stop, a piston, a piston rod, an inwardly extending stop piece to
arrest the upward movement of the piston, an elastic wad attached to the piston
face; in combination with a gun, the whole constructed and arranged so as to
operate as a yielding breech piece, substantially as described and for the purpose
specified.
4. A gun so constructed that its bore extends sufficiently downward as to permit
a lower portion of it to act as an air space, into which an air charging aperture
passes, a piston, closely fitted to the bore of the gun, and a piston rod, passing
through the breech of the gun; the whole constructed and arranged so as to
operate as a yielding breech piece, substantially as and for the purpose specified.
5. The combination with a gun and located at the rear of the bore thereof, of an
air cushion cylinder e, provided with an air charging orifice, an air charging
orifice stop, a piston, a piston rod, and an inwardly projecting stop piece to
arrest the forward movement of the piston all arranged as and for the purpose
set forth.