Improvements in Pneumatic Guns.
Year: 1890

page_text: Date of Application, 19th Nov., 1890
Complete Specification Left, 7th Jan., 1891-Accepted, 7th Feb., 1891
PROVISIONAL SPECIFICATION.
Improvements in Pneumatic Guns.
A communication from HENRY EICHBAUM, of the Grand Hotel du Louvre,
Boulogne, in the Republic of France, Engineer.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E., do hereby declare the nature of this invention to be as follows :—
This invention relates to that class of guns in which the projectile is discharged
from the barrel by the force of a charge of compressed air or gas generally carried
in reservoirs and supplied to the barrel behind the projectile by valves as required.
This invention has particular reference to the conveying of air or gas under
pressure from the reservoirs to the gun tube and I prefer to carry this out in the
following manner :-
I employ hollow trunnions upon which the gun is pivoted into which I lead the
compressed air suitable space being left inside the trunnions but outside the gun
barrel for the passage of the air. A hollow jacket surrounding the gun tube
conveys the air back to the breech end where it is admitted in any suitable manner
to the valve chamber or chambers for admission to the gun tube. Preferably the
trunnion casting is one piece provided with flanges, the breech casing also flanged
is another and the jacket connecting these two is a third independent piece, all or
each of which may be connected with the gun tube for support and to secure their
proper relative positions in any required manner.
If desired the jacket may be made in more than the above mentioned three pieces,
and parts or the whole of it as well as the trunnion and breech parts may be cast or
formed in one with the gun tube or with the separate parts of the gun tube if the
latter be made in sections.
This jacket arrangement of pressure conductor is particularly suitable for use
with an annular valve such as is described in my previous British Patent No. 17185
dated 30th October 1889.
101
Ambon 1000
W. P. THOMPSON & BOULT,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Pneumatic Guns.
A communication from HENRY EICHBAUM, of the Grand Hotel du Louvre,
Boulogne, in the Republic of France, Engineer.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E., 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 that class of guns in which the projectile is discharged
from the barrel by the force of a charge of compressed air or gas generally carried
in reservoirs and supplied to the barrel behind the projectile, by valves as required.
This invention has particular reference to the conveying of air or gas under
pressure from the reservoirs to the gun tube and I prefer to carry this out in the
following manner :-
1 employ hollow trunnions upon which the gun is pivoted into which I lead the
compressed air, suitable space being left inside the trunnions but outside the gun barrel
for the passage of the air. A hollow jacket surrounding the gun tube conveys the

page_text: air back to the breech end where it is admitted in any suitable manner to the valve
chamber or chambers for admission to the gun tube. Preferably the trunnion
casting is one piece provided with flanges, the breech casing also flanged is another
and the jacket connecting these two is a third independent piece, all or each of
which may be connected with the gun tube for support and to secure their proper
relative positions in any required manner.
If desired the jacket may be made in more than the above mentioned three pieces,
and parts or the whole of it, as well as the trunnion and breech parts, may be cast
or formed in one with the gun tube or with the separate parts of the gun tube, if
the latter be made in sections.
This jacket arrangement of pressure conductor is particularly suitable for use
with an annular valve such as is described in my previous British Patent No. 17185
dated 30th October 1889.
In the accompanying drawings
Figure 1 is a longitudinal horizontal section through the gun tube, jacket and
trunnions.
Figure 2 is a cross section on the line. 2-2 of Fig. 1, and
Figure 3 is a cross section on the line 3-3 of Fig. 1, the point of view being
indicated by the position of the section figures of Figure 1.
Like letters indicate like parts throughout the drawings.
A. represents the gun tube and B the valve which in the drawings is shown as an
annular valve passing entirely round the gun tube, the pressure entering the latter
through the openings C. In the drawing Figure 1 the upper part of the valve is
shown entirely open, and the lower part of the valve entirely closed. This form of
valve is indicated in this Specification as being peculiarly adapted for use with the
particular apparatus herein described, but it will be understood that any other
suitable form of valve or valves may be employed instead of that shown.
Dare hollow trunnions to which the air or gas under pressure is admitted by the
openings or any other convenient manner. The casting F which carries the
trunnions in an annular jacket entirely surrounding the gun tube A and connected
therewith at two parts by the annular flange G upon which the jacket F accurately
fits. The joint between the jacket F and the flange G may be slightly tapered if
desired to secure a tight joint, and if preferred a flange or flanges of different con-
struction may be employed so that a bolted joint may be provided between the casing
and the gun tube. H are a number of arms or distance pieces or it may be a
perforated ring, the object being to keep the jacket F and gun tube A. in line
together. Whatever I may be it must serve to hold in the proper relative
position to A. and must allow free passage for the compressed air past it. I is
another part or section of the jacket which for convenience of manufacture and
fitting is shown in the drawing separate from F but it may if preferred be part of
the same casting. The jacket I is provided with a flange J by which it is bolted
to the section F which is also provided with a flange for the purpose.
breech end of 1 is another circular flange L by which the jacket can be bolted to
the flange M of the gun tube A thus securing sections and I in a firm and
pressure-tight manner to the gun tube. In the drawing Fig. 1 both jacket and gun
tube are shown broken between the flanges M. and J. The flange M is provided
with openings N or must be otherwise arranged to allow of the free passage of the
compressed gas past it.
At the
The breech portion O of the jacket is also by preference made as a separate
piece and may be bolted to the flange M of the gun tube by its own flange Pas
shown in Fig. 1. The breech end of the gun which carries the breech block
and other necessary fittings may be bolted directly to the end of the jacket O. It
is not necessary in this Specification to describe more particularly the construction
of the firing valve or its mode of operation and it will therefore be sufficient to say
that with the arrangement above described a free channel T is provided from the
trunnions D to the valve openings C into the gun tube A, the compressed air
entirely surrounding the whole of the gun tube from the trunnions to the firing valve

page_text: inlet, thus mitigating the effect of the introduction of the firing charge into the gun
and providing an ample supply of compressed air to the gun.
Having now particularly described and ascertained the nature of the said inven-
tion, as communicated to me by my foreign correspondent, and in what manner
the same is to be performed, I declare that what I claim is :-
1. In a pneumatic gun the combination with the gun tube of a continuous annular
chamber such as T conveying the compressed gas from the trunnions to the firing
valve substantially as described and illustrated in the accompanying drawings.
2. In a pneumatic gun the combination with the hollow trunnions D of a
continuous or sectional jacket such as FIO substantially as and for the purpose
described and illustrated in the accompanying drawings.
3. In a pneumatic gun a jacket or section such as F carrying the trunnions D
and adapted to be secured to and around the gun barrel A. substantially as described
and illustrated in Figure 1 of the accompanying drawings.
4. In a pneumatic gun the combination with the breech end of the gun tube of a
jacket or section such as O surrounding the firing valve and the gun tube and
conveying the compressed gas to the firing valve substantially as described and
illustrated in Figure 1 of the accompanying drawings.
Dated this 7th day of January 1891.
W. P. THOMPSON & BOULT,
Agents for the Applicant.