Improvements in Pneumatic Guns.
Year: 1894

page_text: Date of Application, 27th Jan., 1894
Complete Specification Left, 27th Nov., 1894-Accepted, 26th Jan., 1895
Improvements in Pneumatic Guns.
I, JAMES WEIR GRAYDON of 32, The Avenue, Bedford Park, Chiswick, in the
County of Middlesex, late a Lieutenant in the United States Navy, do hereby
declare the nature of this invention to be as follows:-
This invention relates to improvements in pneumatic guns for the discharge of
projectiles charged with a high explosive.
The improvements relate, first, to the mode of mounting and the elevating gear
for the discharging barrel whereby the degree of elevation necessary to attain the
desired range may be given more easily than would be possible were the barrel
pivoted upon trunnions at or near the middle of its length.
The improvement consists in mounting the barrel on a pair of main trunnions
situated quite at its breech end and upon a pair of elevating trunnions situated at
the forward part of the barrel and supported by a pair of elbow levers pivoted
upon a sliding fulcrum supported by guides on the gun mounting and actuated by
a bydraulic or other ram pivoted on the gun mounting so that by the movement of
the sliding fulcrum along its guides the angle of the elevating levers is changed
and the barrel is consequently elevated more or less upon the main or breech end
trunnions as a centre.
The improvements also relate to the loading mechanism, which consists of a pair
of hydraulic or other rams extending beneath the barrel and attached to a cross-
head working over the loading table whereby the projectile placed on said table
is hauled into the bore of the gun ready for closing the breech.
To enable this to be done, the breech closing screw-plug is hung in a pair of
counterweighted levers pivoted upon the main trunnions, so that the plug may be
swung upwards to allow the projectile and loading gear to pass beneath it.
When lowered into closing position after inserting the projectile the breech block
is hauled by the loading apparatus into the breech end of the gun ready for closing
the breech.
The improvements also relate to the means by which compressed air is admitted
from the reservoirs to the gun barrel through the main trunnions, both of which
are made tubular to give passage to the air of which the admission is controlled
by valves geared together so as to be operated simultaneously by one hand wheel.
These valves are placed in such position and so combined with lubricators
communicating therewith that the oil will flow into the path of the compressed air
and be carried along with it when the valves are opened, into the barrel of the gun,
the air taking the oil along with it in its passage through the barrel which is thus
lubricated in readiness for the next discharge.
The invention also relates to the training gear whereby the gun mounting is
revolved upon a circular table or path, and consists of an engine actuated by
compressed air and working four or more rollers on which the gun carriage or
mounting rests, the shafts of the rollers converging towards the centre of the
roller path and being there connected to the compressed air engine to which the
supply of air is controlled by a hand-operated valve or valves, the arrangement
being such that the gun may be loaded, trained, elevated or depressed, and fired,
by one person without change of position.
The invention also relates to the storage of the compressed air and to the valves

page_text: and other gear controlling the quantity of air admitted at cach discharge, according
to the range desired.
The air is stored in vessels arranged in rows on either side of the gun mounting
and communicating with pipes common to those of each row and provided with
valves so arranged that any number of these vessels or rows of vessels may be
discharged at a time.
The storage reservoirs of compressed air from which these vessels are charged
are situated at any suitably protected part of the fort and are connected with the
reservoirs on the gun carriage through a central pipe concentric with the axis
about which the gun revolves, and so arranged and coupled with the reservoirs on
the gun as to be unaffected by the recoil of the gun carriage when the gun is
discharged.
The improvements also relate to means of checking this recoil, and consists of
recoil spring cushions mounted on the forward part of the gun carriage and
taking a bearing against the front of the foundation ring upon which the carriage
revolves.
Dated this 27th day of January 1904
J. W. GRAYDON.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents..
Improvements in Pneumatic Guns.
I, JAMES WEIR GRAYDON, of 32, The Avenue, Bedford Park, Chiswick, in
the County of Middlesex, late a Lieutenant in the United States Navy, 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 improvements in pneumatic guns for the discharge of
projectiles charged with a high explosive.
The improvements relate, first, to the mode of mounting and the gear for
elevating the barrel, whereby the degree of elevation necessary to attain the
desired range may be given more easily than would be possible were the barrel
pivoted upon trunnions situated in the usual position towards the middle of its
length.
The improvement consists in mounting the barrel on a pair of main trunnions
situated quite at its breech end and serving as the centre about which the barrel is
elevated and also upon a pair of elevating trunnions which are situated towards the
forward part of the barrel and are supported by a pair of elbow levers pivoted
upon a pair of sliding fulcrums supported by guides on the gun carriage. These
levers are actuated by a piston working in a cylinder pivoted on the gun carriage
which by moving the. sliding fulcrums along their guides causes the elevating
levers to move about the forward trunnions as a centre and the barrel to be
elevated more or less by moving about the main or breech end trunnions as a
centre.
.
The improvements also relate to the loading mechanism, which consists of a pair
of pistons working in cylinders extending beneath the barrel and attached to a
cross-head working over the loading table whereby the projectile placed on said
table is hauled into the bore of the gun ready for closing the breech.
The improvement also relates to the breech-closing screw-plug which is hung in
a pair of counterweighted levers pivoted upon the main trunnions, so that the
plug may be swung upwards to allow the projectile and loading gear to pass
beneath it.

page_text: When unscrewed, the breech plug is hauled out of its seat by the loading
apparatus ready to be raised out of the way, and when lowered into closing position
after inserting the projectile, the breech plug is hauled by the loading apparatus
into its seat in the breech end of the gun ready for being screwed home.
The improvements also relate to the means by which compressed air is admitted
from the reservoirs to the gun barrel through the main trunnions, both of which are
made tubular to give passage to the air of which the admission is controlled by
valves geared together so as to be operated simultaneously by one hand wheel.
These valves are placed in such position and so combined with means of lubrication
communicating therewith that the oil will flow into the path of the compressed air
and be carried along with it into the barrel of the gun, the air taking the oil along
with it in its passage through the barrel which is thus lubricated in readiness for
the next discharge.
The invention also relates to the training gear whereby the gun carriage is
revolved upon a circular table or path, and consists of an engine actuated by
compressed air and working four or mere rollers on which the gun carriage rests,
the shafts of the rollers converging towards the centre of the roller path and being
there connected to the compressed air engine to which the supply of air is controlled
by a hand-operated valve or valves.
The invention also relates to the storage of the compressed air and to the valves
and other gear controlling the volume of air emitted at each discharge according to
the range desired.
The compressed air is stored for immediate use in vessels arranged in rows on
either side of the gun carriage and communicating with pipes common to the
vessels of each row, valves being so arranged that the air contained in any number
of rows of vessels may be emitted at one discharge.
The air compressor and intermediate storage reservoirs of compressed air from
which these vessels are charged are situated at any suitably protected part of the
fort in which the gun is mounted and are connected with the reservoirs on the gun
carriage through a central pipe concentric with the axis about which the gun
carriage turns in training the gun.
The improvements also relate to means of checking any tendency to recoil and
so keeping the gun carriage concentric with the roller path on which it is trained,
said means consisting of spring-cushioned rollers mounted on the forward part of
the gun carriage and taking a bearing against the outer circumference of the
foundation ring upon which the carriage revolves, in combination with a rigid plate
mounted beneath the carriage at the rear part and taking a bearing directly or
through rollers against the inner circumference of the roller path.
The arrangement of the valves and gear controlling the various operations
incidental to charging the reservoirs and working and discharging the gun, is such
that the gun may be loaded, trained, elevated, and discharged, under the control of
one person standing upon the working platform of the gun carriage.
The invention is illustrated in the accompanying drawings, forming part of this
Specification, and will be fully described with reference thereto.
Figures 1 and 2 are a side elevation and plan shewing the general arrangement
of the gun and its mounting.
Figure 3 is a side elevation of the gun in the fully-elevated position, the near
side of the carriage being removed and the training ring being in section through
the centre.
Figure 4 is a plan of the training gear, partly in section to shew details.
Figure 5 is a plan of the elevating gear, shewn separately and partly in section.
Figure 6 is a sectional elevation of the loading and breech-closing gear, parts of
the barrel being broken out and the sections being taken in different planes.
Figure 7 is a plan of the breech end of the gun, shewing the loading table and
the gear thereon for hauling the projectile and the breech-closing plug into the
breech.
Figure 8 is a half-transverse section of the barrel, on line 1-1 Figure 6, anl

page_text: Figure 9 is a half end-elevation of the breech, the adjacent parts being in section
on line 2-2 Figure 6.
Figure 10 is a transverse section of the loading table on line 3-3 Figure 6,
shewing the yoke for hauling the projectile into the bore.
Figure 11 is a transverse sectional elevation of the gun and carriage, the
principal section being taken on the axis of the main trunnions.
Figure 12 is a side elevation illustrating the communication of the compressed
air reservoirs with the main trunnions and the gear controlling the same.
Figure 13 is a horizontal half-section of the breech, shewing the projectile
therein, the breech closed, and one main trunnion in section.
"
Figures 14 and 15 are vertical half-sections of one of the discharging or “firing”
valves in the closed and open positions respectively, and drawn to a larger scale.
Figure 16 is a vertical section (also drawn to a larger scale) of one of the
retaining valves through which the compressed air reservoirs are charged and by
which the emission of air from individual rows of vessels is controlled.
=
The figures are drawn to various scales, (the scale of Figures 1 and 2 being
1 inch 6 feet or 14 millimeters 1 metre) but the same letters of reference
indicate the same parts in all the figures.
=
A is the training ring and roller path on which the gun carriage is supported and
trained by sets of rollers A', A2, journalled in bearings a¹ on the underside of the
carriage, the rollers A¹ being on radial shafts a a geared by bevel wheels A³, A,
with two longitudinal shafts a², a², geared together by mitre wheels A' meshing with
a central wheel A common to both and turning loose on a journal carried by a
bracket B attached to the underside of the carriage. One of the shafts a² carries
a worm wheel c¹ which is driven by a worm c actuated by a compressed air engine
situated at C but not illustrated, this engine being preferably a rotary engine which
is reversible and is actuated by compressed air, the supply of which to the engine
is controlled by a reversing valve or set of valves at a¹ (Figure 2) on the working
platform R, whereby the functions of admission and exhaust are interchanged, so
that the gun may be trained in either direction whilst sighting the object over the
sights a³. The wheel A is concentric with the axis about which the gun revolves
upon the training ring A and through it and through the bracket B passes vertically
the pipe b, b', by which compressed air is supplied to the various sets of air vessels
on the carriage from the air compressor direct or from reservoir vessels located
without the training ring. The carriage is kept centred upon the training ring by
the rollers being conical and their shafts being inclined as shewn, and is prevented
from being displaced under recoil by a plate E fixed to brackets e projecting
downwards beneath the carriage in position to bear directly or through friction
rollers (not shewn) against the inner side of the ring A, and also by rollers D
carried by levers d pivoted at d¹ within a bracket D' and pressed against the
outside of the ring A. by spring cushions d³ and plungers d² carried in the bracket D'
which is fixed to the fore-part of the carriage.
The carriage is constructed of the two side cheeks or frames H suitably braced
together by cross-bars h, h, h2, whereof the first one h serves as a bearer for the
support of the barrel when in its lowest position. The side cheeks H are preferably
constructed of wrought iron or steel members stiffened towards the rear part by
castings H bolted to their inner sides. These castings H' carry the bearings ³ in
which the main trunnions K³ of the barrel K are mounted, these trunnions being
situated at the extreme breech end of the barrel. The barrel K is provided with
a pair of elevating trunnions F situated towards the forward part of the barrel, to
which are coupled a pair of levers F1 whose gudgeons F are co-axial and supported
in bearing blocks f fitted to slide upon ways f₁ on the upper member of the side
cheeks H of the carriage. These levers are braced together by a cross-bar F³
which has journalled upon it the cross-head g of the piston rod G whose piston G¹
works in a cylinder G2 pivoted on a horizontal axis near the middle of its length to
enable it to accommodate itself to the varying position of the levers F¹ consequent
on their fulcrum sliding along the ways f¹. The levers F' are made of the curved

page_text: or elbow form shewn, so that the point of attachment F3 of the piston rod G shall
be out of line with the trunnions F and the sliding fulcrums F, this being necessary
to enable the piston rod G to exert a turning moment on the levers F in all
positions of the latter. The form of the levers F' and the position of the cross-
bar F3 also allows of the barrel coming down to a horizontal position, as shewn in
dotted lines, and the use of a pair of levers F' acting together as one enables the
sliding fulcrums to be mounted at a higher level than would otherwise be possible
and so renders the elevating gear more compact and efficient.
The cylinder G2 is mounted between the two side cheeks of the carriage in a
carrier G³ to which it is bolted by a flange g³, the carrier having trunnions G*
journalled in bearings attached to the side cheeks H and abutting against the
castings H' which receive the thrust. The ends of the cylinder G are closed at
the front by a gland and leather g', through which the piston rod G passes and
at the rear end by a plug g²; pipes g, g, for the supply of compressed air being
connected to the two ends of the cylinder and to the respective trunnions G which
are bored axially and connected at their outer ends by swivel joints to pipes
leading to a controlling valve box situated at f³ (Figure 2) on the working
platform R. The valves in this box 3 control the distribution of compressed air
to cylinder G2 so as to reverse the functions of admission and exhaust to the two
ends of said cylinder.
The pipes g, y, instead of being coupled to axial passages in the trunnions,
might have spring coils in their length to accommodate the angular motion of the
cylinder.
The degree of elevation given to the gun is denoted by an index j fixed to the
main trunnion K2 and moving over a scale on the side frame H of the gun carriage,
at the working side of the gun, as shewn in Figure 12.
I is the loading table whose side cheeks are bolted to the gun barrel K around
the main trunnions K2 so that the loading table partakes in the angular movement
of the barrel and always maintains the same relative position thereto, so as to admit
of the gun being loaded in any position of elevation.
This table has a shallow central longitudinal groove to form a guide way for the
projectile K³ whilst the latter is being hauled into the breech.
This operation is performed by a cross-head l' sliding on ways at the sides
of the table and coupled by rods L to the pistons of the loading cylinders.
The cross-head acts on the projectile through the medium of a yoke ³
attached to thrust rods i pivoted at to the cross-head I so as to enable
the yoke to be thrown back as shewn in Figures 6 and 7, out of the way
when not in use. The projectile K³ is shewn as of reduced diameter at the base
so as to present a shoulder for the yoke to act upon, the yoke being adapted
to enter the bore of the gun so as to carry the projectile to its proper position
therein. When the projectile arrives at this position it is prevented from slipping
backwards (when the cross-head and yoke are withdrawn after the loading has been
performed whilst the gun is in the elevated position) by a self-engaging spring-
latch mounted in the upper side of the breech end of the barrel, and engaging
with the shoulder at the base of the projectile.
Jis the breech plug to be screwed into the barrel in the ordinary way. It is
provided with an axial tail rod J' journalled in a bearing in a cross-bar carried
by a pair of elbow levers J2 which are mounted on roller bearings about the main
trunnions K2 of the barrel K, the breech plug and levers being counterbalanced by
weights J³ carried upon the short arms J of the said levers so that the breech
plug when unscrewed may be easily raised to the position shewn in Figure 6, in
order to allow the projectile to be introduced through the breech opening Ki
into the barrel of the gun. The rotation of the breech plug for screwing and
unscrewing it, is effected by a hand lever inserted into holes in the end of the
tail rod J which is free to slide through its bearing j³. When the breech plug is
withdrawn to its full extent, a spring-actuated bolt 12 mounted on the bearing j
engages with a hole in the tail rod J¹ whereby when the breech plug is swung

page_text: upwards as shewn in Figure 6, the breech plug is prevented from coming in contact
with the barrel in consequence of the tail rod sliding through its bearing. In
order to bring the breech plug as near as possible to the axis of the main trunnions,
about which it oscillates, and so reduce its moment about said axis, the face of the
plug J is concaved spherically to enable it to clear the corresponding rounded
upper part of the breech end of the barrel. The moment of the weights J³ is
rather greater than that of the breech plug and a latch i is provided on the one
side of the loading table I to retain the breech plug in its lowered position co-axial
with the bore of the gun. The hauling of the breech plug in and out of its
scat K in the breech is effected by the cross-head I¹ acting on the rear end of the
tail rod J to which the cross-head is coupled when withdrawing the breech plug,
by a pin temporarily passed through the holes in the tail rod.
The rods L through which the cross-head 1' is operated are coupled each to the
rod L common to a pair of pistons 15, 16, working in cylinders LL2 carried at
their outer ends in brackets 1, ', fixed to the barrel K, the inner ends being
supported in a carrier L³ also fixed to the barrel K. This carrier contains cup
leather packings 12 through which the piston rod L* passes and by which the
adjacent inner ends of the cylinders L', L2, are separated. Each piston 15, 16, is
single acting so as together to constitute a double acting piston, and the cylinders
are supplied with compressed air through pipes 13, 1, leading from a set of
controlling valves situated at 17 (Figure 2) whereby the functions of admission and
exhaust through the pipes 13, 14, are interchanged at the will of the operator. The
pipes,, are made sufficiently flexible, by means of spring coils, to accommodate
the angular motion about the main trunnions in elevating the gear.
The projectile K³ is shewn in Figure 1 as slung from a trolly M (Figure 3)
running on rails m supported by uprights m' rising from the side cheeks at the rear
end of the gun carriage, the rails overhanging at the rear to enable the projectile
to be raised by tackle from outside the training ring A and then carried forward
by the trolly over the loading cross-head 1' and deposited on the loading table I
in front of said cross-head.
N', N2, N3, N4, are rows of inverted bottle-shaped vessels in which the com-
pressed air for discharging the gun is stored, the vessels of each row being
coupled by stirrup-clamps n to a pipe N common to all the vessels of a row.
There are two or more rows at each side of the gun carriage, the pipes N of the
rows at the same side being connected to the branch pipes O of a rising pipe O'
common to all the rows of vessels at the same side of the carriage.
The connection of the storage vessels with the pipe O' is controlled by retaining
valves (shewn in Figure 16) one in each branch O so that the air stored in one or
more rows of vessels may be used at one discharge. The pipe O' at each side of
the carriage is coupled to the upper end of a casing Q which is connected by a
branch pipe k with the bore k of the adjacent tubular main trunnion K2 of the
gun, through which the compressed air stored in one or more rows of vessels is
admitted to the bore of the gun just between the front of the breech plug and the
base of the projectile for the purpose of discharging the latter. The branch
pipes are screwed into the main trunnions by a fine screw thread, as shewn in
Figure 11, so as to resist the internal pressure at the moment of firing, and permit
of the slight angular motion of the trunnion K relatively to the branch pipe k²
necessary for the elevation of the gun.
The emission of air from the storage vessels to the bore of the gun is controlled
by "firing " valves contained in the casings Q' and whereof the construction is
shewn detailed in Figures 14 and 15. The storage vessels are charged by an air
compressor situated outside of the training ring and delivering air through the
central pipe b (Figure 3) thence through pipe (which is connected to pipe 6 by
a swivel joint) to a stop valve controlled by the hand wheel 63 (Figure 2) thence
through branch pipes 62 (Figure 11) to the pipes 01 just above the firing valves.
To enable the air to pass the retaining valves contained in the breeches pipes O,
these valves are constructed as shewn in Figure 16 wherein 03 is the retaining

page_text: valve closing upwards against a seat in the casing.0 above the branch to the
pipe N, the valve being carried by a stem o² working in a guide cylinder O2 formed
in the lower cover of the valve chamber. The valve 03 is closed against its
seat by a spring of confined in cylinder 0 beneath the lower end of the valve.
sten, which yields when overcome by a superior air pressure above the valve 0³.
to allow the air to pass into the row of reservoir vessels.
The opening of the valve O³ (to allow the charge of compressed air to pass from
the storage vessels into the pipes O¹ in readiness for firing the gun by opening the
"firing "valves at the trunnions) is effected as follows:-The retaining valve
chamber is connected by a pipe O with the lower end of the cylinder O, the
pipe O being connected to the valve chamber at a point below the head of the
valve when in its closed position. Upon this pipe are placed a stop valve o
and an exhaust valve o' which is situated between the stop valve o and the
cylinder O. The valve stem o² has a bore o' extending completely through it and
terminating at the upper end in a pea-valve 0+ closing downwards upon a seat in
the main valve O³ and held in place thereon by claws which allow it to rise under
pressure from beneath. To open the valve 03 against the pressure of its spring o
it is first necessary to establish equilibrium of pressure between N and O assuming
such equilibrium does not already exist in consequence of pipe () being under
pressure from the charging pipe 2) which is done by opening the stop-valve o to
allow air to pass from N through 05, cylinder 02, piston bore o, and pea-valve 01.
Then by closing stop-valve o and opening exhaust-valve o' the equilibrium is
disturbed and the air pressure in O acts with its full force on the face of the
valve 03; thus overcoming the spring o. To prevent loss of pressure by leakage.
past the valve stem o² it is provided at the lower end with a cup-leather o³ fitting
cylinder O2 and to relieve the cup leather the under side of the valve 03 is formed
as a valve o' closing down upon a seat at the upper end of the valve stem guide, as
shewn in dotted lines. The valve O³ is raised to the closed position by its spring o
when the pressure in O falls by the discharge of the gun. The valves 06, 07,
controlling the operation of the retaining valves 03 at the left hand side of the
gun are arranged at the right hand or working side of the gun, so as to place the
means of regulating the force of the discharge within reach of the gunner by
whom the loading, training, and elevating, of the gun is controlled.
The "firing" valves (of which one is shewn in two positions in Figures 14.
and 15) are each contained in a casing Q', the valve being formed by a piston Q*
lowered by a vertical shaft Q provided with a quick-pitched multiple-threaded
screw Q working in a nut Q on the lower cover Q. This piston valve has
oppositely directed cup-leathers q', q³, clamped upon it by the cap g² and the collar q*,.
the intermediate body portion Q being split spirally for a portion of its length so
as to be slightly compressible in the longitudinal direction in screwing up the
collar 9. The upper part 3 of the valve stem is tubular and has orifices q, q,
to allow the air pressure to pass from above to below the piston valve Q. The
piston valve Q works within a sleeve Q5 which works as a piston within the part of
the casing Q which is below the circumferential groove *. forming part of the
passage leading to the tubular main trunnion of the gun. The sleeve Q is pressed.
upwards by a spring Q beneath it until its upper end abuts against the part of the
valve casing Q above the groove k² in which position the internal surfaces of the
sleeve and case form a continuous bore, for the piston valve Q to work in. The
sleeve has a cup-leather q and gland q at its lower end, and a double cup-
leather and junk-ring g' are provided at the bottom of the casing Q to prevent
leakage at those points. Assuming the valve to be closed, as in Figure 14, and
under firing pressure from pipe 0, the shaft Q, Q3, Q³, is rotated so as to draw the
piston valve Q' down within the sleeve Q5 which remains stationary owing to. the
upward pressure both of its spring and of the air acting on its lower end, until
the upper leather q¹ has passed the joint between the upper end of the sleeve Q and
the casing Q whereupon by the further downward motion of the valve Q the sleeve
is drawn down by the shoulder q on the glaud q* striking upon an internal shoulder q

page_text: at the lower part of the sleeve, the air passage k² being thus opened and the charge
of air emitted to the gun barrel. By means of the sleeve Q, distortion of the cup-
leather by being blown out into the groove is prevented, so that when the
valve Q is closed the cup leather will again enter the upper part of the casing Q',
the cup leather being housed within the sleeve during the opening motion before
the passage kis uncovered, and conversely during the closing of the valve, the
sleeve being raised by its spring so.as to cover the passage k² before the leather q
is unhoused.
The lubrication of the bore of the gun may be effected by pumping in oil by
means of a force pump connected to each of the air supply pipes so that, the stop
valve at being closed, the oil will be delivered on to the domed top 93 of the
firing valve Q and will lie on the marginal surface in readiness to be blown off into
the passage k³ and so into the gun barrel immediately the sleeve Q is lowered.
The rotation of the screw shaft Q necessary to open the firing valve is imparted
through a mitre wheel P³ connected by groove and feather 9 with shaft Q and
supported on a hollow standard p which also acts as a guide for the lower end of
shaft Q, the mitre wheels of the two valve shafts Q (whose threads Q are
respectively right and left handed) being geared together by a cross-shaft pa
mounted in bearings p³ and having corresponding mitre wheels P2 on its ends, said
shaft being rotated by a hand fly-wheel P' which is locked against premature motion
by a detent p' engaging in a notch in the periphery of the wheel and with a lug on
a locking lever P (Figure 12) pivoted at p to the side frame of the gun carriage.
By withdrawing the lever P so as to release the detent pl and turning the hand.
wheel P in the direction of the arrow, the two firing valves at the two sides of the
gun are opened simultaneously to allow the compressed air from one or more rows
of vessels at each side of the gun to be emitted through passages k in the two main
trunnions into the bore of the gun. The pitch of the threads Q2 is such that one
turn of wheel P1 is sufficient to fully open the firing valves, the opening motion
being accelerated by the air pressure upon them.
The compressed air necessary to load, train, and elevate, the gun is supplied
from supplementary air vessels S carried beneath the gun carriage, as indicated
in Figure 4, and charged by the air compressor through a branch pipe and check
valve connected with the central pipe 61, all these vessels being in communication
with pipes leading to the several valve boxes at 17, a', and ƒ³, (Figure 2) by which
the operation of the loading, training, and elevating, mechanisms are respectively
controlled.
The gun of the size indicated by the scale given in the list of figures is
designed to work up to a pressure of five tons per square inch in the storage
vessels.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that
what I claim as my improvements in pneumatic guns is :-
1. Mounting the barrel on a pair of main trunnions at the breech end as the
centre about which the barrel is elevated and also on a pair of elevating trunnions
towards the fore end, as a point of attachment for elevating gear substantially as
and for the purpose specified.
2. Mounting the barrel on a pair of main trunnions at the breech end and also
ou a pair of elevating trunnions, supported on elevating levers and pivoted upon
fulcrums adapted to slide along ways on the gun carriage so as to vary the elevation
of the barrel by varying the angular position of the levers relatively to the barrel
and the carriage, as specified.
3. The combination, with the elevating levers working on sliding fulcrums, and
coupled to elevating trunnions, as described, of an operating piston coupled to the
levers at a point out of line with the sliding fulcrums and elevating trunnions and
working in a cylinder pivoted to the gun carriage so as to accommodate itself to
the angular motion of the levers, substantially as specified.

page_text: 4. The combination, with the barrel mounted on main and elevating trunnions,.
as described, of a loading table partaking in the angular movement about the
main trunnions, and of loading gear consisting of a crosshead adapted to carry the
projectile into the bore and moved along the table by pistons working in cylinders.
parallel with the barrel, as specified.
5. The combination of the loading gear operated as described with the breech
plug for the purpose of hauling the latter in or out of its seat in the breech in
readiness to be screwed in, or after it has been unscrewed, as specified.
6. Mounting the breech plug to slide and rotate in a bearing pivoted to swing
about the main trunnions and counterweighted so as to be thereby raised clear of
the breech opening, for loading the gun, as specified.
7. Making both of the main or breech trunnions tubular and opening directly
into the breech between the breech plug and the projectile, substantially as
specified.
8. The combination, with the tubular main or breech trunnions, of branch pipes
connected axially thereto and to air supply pipes connected to rows of compressed
air vessels mounted at either side of the carriage and of firing valves operating as
described so as to control the emission of air to the barrel, as specified.
9. Gearing together the firing valves so as to cause them to be operated
simultaneously, as specified.
10. The firing valves each consisting of a screw operated piston valve and spring
actuated sleeve combined for operation as specified.
11. The combination, with the rows of storage vessels on the carriage and their
connecting pipes, of the retaining valves operated pneumatically from the working
platform by the pressure of the air which they retain, as specified.
12. The combination, with the rows of storage vessels on the carriage, of
retaining valves independently controlling the emission from each row so as to
enable the volume of the air emitted to be regulated, and of firing valves deter-
mining the moment of admission through the trunnions to the barrel, of the air so
emitted, as specified.
13. The herein described means of checking recoil and keeping the gun carriage
concentric upon the training ring, substantially as specified.
14. The combination, with the vertically moving domed piston firing valves, of
means of supplying oil on to the said valves so that the oil will be carried by the
air into the barrel when the valves are opened.
15. The improved pneumatic gun substantially as herein specified.
Boted The 97Kb dow
November
ON
הנאום אהnon
November 1901
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents..