IMPROVEMENTS IN "PNEUMATIC CANNON
Year: 1884

page_text: COMPLETE SPECIFICATION.
I WALLACE ALEXANDER BARTLETT, of the City of Washington, in the District
of Columbia and United States of America, Patent Solicitor, do hereby declare
the nature of my invention for IMPROVEMENTS IN "PNEUMATIC CANNON, 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 cannon of the character more particularly described in
another application (N° 4355) of even date herewith, to which reference is made
for a more complete statement of the nature thereof.
Fig. 1, is a side elevation, partly in section of portions of a gun tube and supply
pipe, and valves, and valve mechanism.
Fig. 2, is a rear elevation of a breech closing mechanism.
.Fig. 3, is a front view of the muzzle.
Fig. 4, is a section of a portion of the muzzle enlarged.
Fig. 5, is an elevation of one end of the operating valve.
Fig. 6, is a plan of said valve.
Fig. 7, is an elevation of portions of tubes and valves and modified valve
mechanism.
Fig. 8, is a side elevation of gun and upright flask.
Fig. 9, is a muzzle view of gun, and
Fig. 10, is a plan of valve.
Fig. 11, cross section of gun and flask through trunnions, and
Fig. 12, is a detail view thereof.
In Fig. 1, the gun tube, 12, and supply pipe, 42, are connected by an elbow
piece, 24, which is swiveled at, k², in collar, When this breech piece is swung
to one side, as in Fig. 2, the breech is open for loading. When the breech is closed
a semicircular flange, g2, on the gun tube grooved as shown at, h², receives a
projection from the side of elbow, 242, and at the same time a tongue, f, on the
elbow closes past the flange, e, on the gun tube, thus forming a lock against
backward pressure.
These locking grooves and projections may be faced with
rubber or other packing to make a gas-tight joint.
Near the muzzle of the tube, 12, a lever, m², may be pivoted, projecting very
slightly into the path of the projectile at its outer end.

page_text: The lever end will be sustained by a spring, and said lever, m², will be depressed
by the projectile as it leaves the muzzle so as to bear on the short arm of, o³, to
rock the bell crank lever, på, and draws upon rod, q2, for a purpose hereinafter
explained.
The valve, 4, is mearly a relief valve.
The valve, 5, is a rotary valve, which works always in one direction to open or
close the supply pipe, 42, One end of the valve stem projects from the valve-
casing and supports a ratchet wheels, which has four teeth. The other end of
the valve stem projects from the casing, and bears upon its end a ratchet wheel, u²,
and is surrounded by a sleeve, v2, which carries a spring pawl to engage with the
ratchet wheel. This sleeve, v³, is propelled by a strong spiral spring, w².
The tendency of the spring, w³, is to revolve sleeve v³, and this sleeve, by its
pawl engaging the ratchet on the valve stem, will turn the valve when free to
do so.
A trigger, ³, engaged the four toothed ratchet s², and when in engagement holds
the valve from turning, against the force of the spring, w³, Suppose the trigger
to be tripped and immediately returned to position, a single tooth on the wheel s²,
will be released, the valve will be revolved a quarter of a revolution, and stopped
when trigger, engages the next tooth.
The valve is so made that a quarter revolution turns it from closed to open
position, a further quarter closes it.
The trigger, 2, is connected to rod, q2, before described, so that a pull on said
rod will operate the trigger, but is so balanced by springs as to immediately returns
to position to stop the next tooth on wheel, 82.
The parts will be provided with buffers to overcome the shock of sudden
stopages.
Suppose a projectile to be placed in the gun, and the trigger to be pulled, to
permit the passage of compressed air through pipe, 42, and the breech block, to the
gun tube. The trigger, will stop the valve in its open position until the
projectile depresses lever, m², when this lever and its connections will again trip
the trigger, 2, and the valve will be turned by its spring until again stopped in
closed position by the trigger. To wind up the spring without the necessity of
revolving the valve backward, a wrench, Fig. 5, may be engaged with holes in the
sleeve, v2, and the sleeve turned, its pawl riding over the ratchet teeth, leaving the
valve at rest. The valve may be held in position by a similar wrench engaging
the other end of its stem should this be necessary In Fig. 7, 1 show a small
cylinder, m, near the muzzle of the gun, which communicates with the bare. In
this cylinder, m', I place a piston, n, the rod from which bears on a wire, of, which
connects with the electro-magnet, l.
Another wire, p, leads to said magnet through a battery. The magnet, l, is in
such proximity to trigger, k, as to lift said trigger when the circuit is closed. The
trigger, k, engages with stops i, each placed to stop the revolution of the valve
after one-fourth of a revolution.
The operation of the valve is the same as that just described, except that the
trigger is controlled by electric instead of mechanical devices.
The circuit may of course be closed by other means than by the passage of the
projectile, as by clock work or by hand, and the valve may be controlled from any
other location as well as from near the muzzle of the gun, I do not limit myself
to the precise mechanism shown.
In Fig. 8, I have shown the gun tube, l, mounted on the reservoir, 3', so as to
be clevated and depressed without moving the reservoir.
For traversing the gun the reservoir should turn on a pivot or balls, and may be
charged with compressed air from a suitable compresser through a pipe which
enters at the pivot or at any other point.
The trunnion block, a', has a passage, c, for the gun tube, 14, and is supported
by standards, e, et, Fig. 11, which have passages leading to the flask, 3, and

page_text: The supply pipe, +", leads from this chamber to the breech of the gun, the relief
valve and operating valve being arranged in said pipe as shown.
The trunnions may enter the trunnion supports, e', and come to a thin edge, as
in Fig. 12, to prevent gas escape. The strut, 2, tixed to the trunnion piece serves
as a support for the front portion of the gun tube.
In Fig. 13, I show a side elevation of a gun and supply pipe supported in a
trunnion block mounted on the flask.
Fig. 14, is a longitudinal section of a gun tube.
Fig. 15, is a front elevation of gun tube and reinforced.
Fig. 16, is an elevation of a reinforced piece.
Fig. 17, a perspective of the same, reversed.
Fig. 18, is a section of trunnion block and its supports.
Fig. 19, is an enlarged view of a portion of the same.
Fig. 20, is an end view of the trunnion piece and its support.
The cylindrical flask, 33, serves as a support for the trunnion bearers, (³.
The trunnions, c³, are supported in these bearers. The block, b³, from which the
trunnions project, is a short cylinder or segment having a passage, e³, axially
through it for the gun tube.
The cap, ³, on the flask is hollowed out to form a seat for this trunnion piece,
and has a passage way, g³, leading from the flask to an elbow passage ƒ³, which
connects with the pipe, 4³.
The edges of the passages, g³, and, fs, are made thin or clastic at, x³, and, y³, so
that the gas pressure will serve to close and make tight the joint, at the same time
permitting a rocking movement of the piece, 63, which permits of the elevation or
depression of the gun.
The gun tube, 13, is strengthened by a sleeve, 23, which sleeve is a hollow
cylinder made up of sections, a³, each forming a portion of a circle, and having edge
flanges, a, and end flanges, a23, by which the parts may be bolted together.
In other words, this strengthening sleeve is similar to the hollow column well
known as the "Phoenix" column, and it is made in sections of suitable length,
which sections may be bolted or otherwise secured to the trunnion piece.
Should the supply pipo need further support than it gets from the trunnion
piece and breech frame, bands may be thrown round this pipe and the rear section
of the gun tube, or this pipe may also have a flanged sleeve.
The drawing Fig. 14, is intended to illustrate a modification of the gun tube of
peculiar construction. As the tube is not rifled, it is found that great accuracy of
finish in the rear portion of the bore is not necessary.
I therefor make a large portion of the gun tube or lining of ordinary drawn
tubing (steel, iron, or brass) and the muzzle section, as at, 133, finely finished
inside.
This construction will save some expense in finishing the rear portion of the gun
tube.
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 clain is :-
1. A pneumatic or similar cannon mounted on a flask which serves as a carriage,
a supply pipe leading from the flask to the gun through the trunnions, and supports
or braces for the gun tube from the trunnion piece.
2. A pneumatic or similar cannon having an operating valve, and power mechanism
to throw said valve to its open position, at the pull of a trigger.
3. A pneumatic or similar cannon having an operating valve, and power
mechanism to close the same when free to move.
4. A pneumatic or similar cannon having an operating valve and power
mechanism to move the same, and retarding nechanism by which the time which
the valve remains open may be regulated.

page_text: 5. A pneumatic or similar cannon provided with a power-driven operating valve
and a relief valve for the same placed between the operating valve and the flask.
6. A pneumatic or similar cannon having a power driven operating valve, and
electrical connections thereto by which the movement of the valve may be controlled
from a distance, substantially as described.