A Duplex Automatic Machine Gun.
Year: 1894

page_text: bis Print is in accordance with the Original Specification as it stands after
Amendment (under Section 11 of the Patents, &c. Act, 1883), as required
by the decision of the Law Officer of the 24th day of April 1896.
Date of Application, 4th Oct, 1894
Complete Specification Left, 1st Aug., 1895-Accepted, 28th Sept., 1895
A Duplex Automatic Machine Gun.
I, HAROLD THOMAS ASHTON, of No. 10 Lansdown Road, Leo, in the County
of Kent, Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to machine guns arranged to be loaded and fired
automatically as long as cartridges are supplied to them by the power derived
from the recoil
For this purpose I arrange a gun with two barrels so that the recoil of the one
barrel is utilised to unlock its own breech mechanism, and start the extraction of
the empty cartidge case from its chambor, and at the same time to completely open
the breech, empty the chamber, reload, and cock the firing gear of the other
barrel, the breech mechanism of which had been previously unlocked by its own
recoil Each barrel has a separate tigger both of which can be kept in a forward
position, and, while they are so kept, the firing goes on automatically one barrel
after the other. If only the trigger of the loaded barrel be pressed forward that
barrel only files, loading the other ready for firing when its trigger is pressed
for waid, thus single shots may be fined at any intervals
The recoil movement of the one bariol effects unlocking of its own breech bolt,
starts the extraction of the shell of the fired cartridge, diaws bach the breech
bolt of the other barrel ejecting the shell from that barrel and finally draws a
cartridge from a travelling belt and places it in front of the breach bolt of the
stationary barrel. When these movements are completed, the barrel which recoiled
19 advanced by spring pressure to its firing position and locked in that position,
during which movement the breech bolt of the stationary bariel is advanced
pushing the cartridge into the chamber and becoming locked.
During the advance of the breech bolt a catch on its spring stiker meets a stop
which holds it until the bolt completing its advance allows withdrawal of this stop
and thereupon the spring striker being released completes the locking of the holt
and fines the chargo. The recoil of this barrel acts in the same way and, thus, so
long as cartridges are supplied firing from the barrels goes on alternately.
The cartridges are held in chips on a travelling belt which at each advance of
each barrel to fing position is fed forward by a pawl so as to bring a fresh
cartridge into position for supplying one of the barrels
The oxtractor for each barrel is fitted on the breech bolt so that as the bolt
makes its back stroke, the extractor by meeting an inclined stop is pushed aside
laterally and remains holding the extracted shell until the bolt, completing its back
stroke, acts on a level which throws off the shell and pushes a fresh cartridge
from off the belt into the space in front of the bolt.

page_text: By thus employing two barrels firing alternately I give more time for the
various movements to take place than can be given when only one barrel is used.
I also give each barrel time to cool a little in the intervals between its successive
discharges, and thus a water jacket may, if necessary, be dispensed with.
I prefer to place the barrels the one above the other and to enclose the lock
mechanism in a casing the two sides of which can be opened so as to give complete
access to the mechanism
Daied this 4th day of October 1894.
ABEL & IMRAY,
Agents for the Applicant
A Duplex Automatic Machine Gun.
I, HAROLD THOMAS ASHTON, of No. 10 Lansdown Road, Lee, in the County
of Kent, Engineer, do hereby declare the nature of this mvention and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement
My invention relates to machine guns arranged to be loaded and fired
automatically as long as cartridges are supplied to them by the power derived
from the recoil.
For this purpose I arrange a gun with two barrels so that the recoil of the one
barrel is utilised to unlock its own breech mechanism, and start the extraction of the
empty cartridge case from its chamber, and at the same time to completely open
the breech, empty the chamber, reload, and cock the hring gear of the other barrel,
the breech mechanism of which had been previously unlocked by its own recoil.
Each barrel has a separate tiggor both of which can be kept in a forward position,
and, while they are so hept, the firing goes on automatically one bariel after the
other If only the trigger of the loaded barrel be pressed forward that barrel
only fires, loading the other ready for firing when its trigger is pressed forward,
thus single shots may be fired at any intervals.
The recoil movement of the one barrel effects the unlocking of its own breech
bolt, starts the extraction of the shell of the fired cartridge, draws back the breech
bolt of the other barrel ejecting the shell from that barrel and finally draws a
cartridge from a travelling belt and places it in front of the breech bolt of the
stationary barrel. When these movements are completed, the barrel which recoiled
is advanced by spring pressure to its firing position, during which movement the
breech bolt of the stationary barrel is advanced pushing the cartridge into the
chamber and becoming locked
.
During the advance of the breech bolt a catch on its spring striker ineets a stop
which holds it until the bolt completing its advance allows withdrawal of tlus stop
and thereupon the spring striker being released completes the locking of the bolt
and fires the charge. The recoil of this barrel acts in the same way and, thus, so
long as cartridges are supplied, firing from the barrels goes on altornately. The
cartridges are held in clips on a travelling belt which at each advance of each
barrel to firing position is fed forward by a pawl so as to bring a fresh cartridge
into position for supplying one of the barrels.
The extractor for cach barrel is fitted on the breech bolt so that os the bolt
makes its back stroke, the extractor moves a certain distance with it holding the
extracted shell until the bolt, completing its back stroke, acts on a lover which
pushes a fresh cartridge from off the belt into the space in front of the bolt, this
fresh cartridge pushing off the empty shell.
By thus employing two barrels firing alternately I give more time for the various
movements to take place than can be given when only one barrel 19 used. 1 also

page_text: discharges, and thus a water jacket may, if necessary, be dispensed with.
I prefer to place the barrels the one above the other and to enclose the lock
mechanism in a casing the two sides of which can be opened so as to give complete
access to the mechanisın.
Such being the general character of my invention I shall now describe the
mechanism of the duplex gun referring to the accompanying drawings
Fig A is a side view, Fig. B is a plan, and Fig C is a rear end view showing
the semicircular casings which onclose the lock mechanism and the bolt guide folded
down. The other figures, showing details, are drawn to an enlarged scale, us
follows:-
Fig. 1 is a side view showing upper barrel locked in act of firing, lower barrel
with breech unlocked
Fig 2 is a side view shewing upper bariel fully recoiled.
Fig. 3 is a side view of the mecham-in on the other side, the upper barrel being
fully recoiled.
Fig. 4 is a sectional plan showing lock and feed lever of lower barrel.
Figs and 4 are sections at the front and rear limbs of the feed lever
Fig. 5 is a vertical section through both barrels in the condition corresponding
to that of the mechanism in Fig
Fig. 5 is a plan of the locking tumbler.
Fig. 6 is a transverso section on the line 6, 6 of Fig. 5 looking to the rear
Fig. 7 is a transverso section through cartidge feed belt.
Fig. 8 is a transverse section on 8, 8 of Fig 5
Fig 9 is a transverse section on 9, 9 of Fig 5 looking to the front
Fig. 10 is a side view and plan of upper bolt extractor and locking tumbler.
Fig. 11 is a side view of tho striker
Fig. 12 is a side view and plan of the cam lever for withdrawing bolt
Fig. 13 is a side view of the left spring and link motion.
Fig. 14 is a side view of the right choek.
Fig. 15 is an elevation of feed belt in its guide.
Fig. 16 is a plan of the upper feed lever.
Fig 17 is an end viow of the frame.
Figs. 18 and 19 are side views shewing in two positions hand gear for recoiling
the barrels
As shown in Figs A, B and C the gun according to my invention has two
barrels B 13 the one above the other projecting from a frame F which can_bo
mounted by fixings at fou a suitable stand such as is used for machine guns. The
frame has on each side of it a set of mechanism, the two sets being substantially
identical but the one inverted relatively to the other. Both sets of mechanism are
covered by lids C which are cylindrical segments hinged at their lower edges to
the frame al c so that they can be turned down on their hinges as shewn in Fig. C
loaving the mechanism exposed. When the gun is in use the covers Care turned
up and held by any convenient fastenings c', the mechanistu being thus enclosed in
a cylindrical casing indicated by the dotted circle in Fig. C. One of the covers C
carries a guide for the belt which feeds cartridges as will hereafter be
explained.
As shown in Figs. 5 and 8 the two barrels B' B' are fixed in the front part cach
of a slide S S in the manner of a bayonet joint, each barrel having on its breech
two coll segments projecting outwards and each slide having two collar segments
projecting inwards as shown in Fig. 4. On inserting the breech with its segments
passing between those of the slido, and turning the barrel one quarter round its
segments are engaged behind those of the slide, then filling pieces 6¹² are inserted
to prevent the barrel from turning.
The slides with the barrels thus fixed to them are fitted to slido longitudinally in
guides (see Figs 5, 6 and 7) formed in the frame F, so that when a charge of
either bariel is fired its slido moves back in opposition to a spring S³ for the one

page_text: barrel and S for the other. These springs are accommodated, as shown in Figs. 6,
7 and 14 in the segment covers C, each having its one end, as shown in Figs 13
and 14, connected by an adjusting screw to the front end C³ of the cover C, its
other end 19 connected to nearly the middlo of a lover C having its ono end jointed
to a radius C which is pivotted on C', and its other end engaged with a pin 1 on a
lever L, which, as will hereafter he described acts on the slide S¹ of the one
barrel B' and on the breech bolt D' of the other barrel B. By the arrangement
shewn in Fig 13 the strain of the spring is almost nil when it is most extended
and becomes to a certain extent equalised throughout the rest of its stroke. The
lever L shown separately in Fig. 12, 18 pivotted at 1 on the frame F and has
pivotted on its end a squaro piece which might be a roller, which is engaged
between two shoulders d d formed on the bolts D¹' D' There is also formed on
the face of La cam which bears against a projection S on the one slido S¹,
and Ss on the other slide S2. When the upper bariel B' has recoiled, as shewn in
Figs 2 and 3, the projection S¹ on its slido acting against the cam on the lover L
bas caused that lover to move to the position shewn in Fig 3, and this lever acting
on the bolt D2 has withdrawn it from the breech of the barrel B' a sufficient
distance to admit a cartridge between the bolt and the breech. The recoil of the
barrel B and slide S¹ carrying with it the bolt D₁ effects the pailial cocking of
the stinker in the following manner On the bolt D is pivotted a lever I' the tail
of which, during the recoil, meets a projection pl from the fixed frame by which the
level P is thrown into the position shown in Fig. 2. The other end of the lever P
being engaged in a notch p² of the striker P, the strike is thus rotracted in
opposition to the spring pa and is held in its retracted position by a spring sear in
the form of a bell crank levor p'. The striker in this position is not fully cocked.
When the bariel B₁ is in the firing position as in Figs. 15 and 5ª its bolt D' 19
held by a locking tumbler T which is pivotted on the slido S' and which bears
against a concave surface sa formed in the slide S', and has a shoulder t bearing
against the end of the bolt D. In this condition of the parts a projection P² on
the stiker catches over a projection t' on the tumbler thus holding the tumbler in
the locking position (Figs. 1 and 5) when the striker advancos to fire, and thus
proventing any retreat of the bolt during the firing. After the barrel has recoiled
about half way an arm on the tumbler T meets a fixed projection f' which may
be olastic, and as the bariel continues to recoil the tumbler T is thus caused to
turn to the position shewn in Figs. 2 and 10 leaving the bolt D' partially
withdrawn by the action of n cam face t on the tumbler and thus free to move
bach. This cam face 15 bo shaped that when the bolt D' advances in the slide S¹
it turns the tumbler T causing it to lock the bolt in its forward position When
the tumbler is turned to the position shown in Fig 10 a projection on its
shoulder passes along the inclined edge of the projection P of the striker and
finally springs over its front termination (sce Figs. 2 and 5) being thus prevented
from resuming its locking position until the striker is fully cocked.
The bring in one barrel, as already explained, retracts the bolt of the other
barrel, consequently when the charge in B2 is fired the bolt D¹ is fully
retracted
On approaching the end of this backward motion, the tail of the lover P
meets second projection p (Fig 3) whereby the stuiker is fully cocked The
extraction of the shell of a fired cartridge is effected as follows. On the bolt D'
is fitted a plate E terminating in front in two claws adapted to take hold of the
head of the cartidge. This plato is free to move a short distance to and fro ou
the face of the bolt between a rear shoulder e and a front shoulder el. When the
tumbler T is turned to unlock the bolt the cam face 3 acting upon a hook of the
plato E and on the shoulder e of the bolt moves the bolt and extractor slightly
backwards thus starting the extraction of the shell
The complete extraction is effected by the retreat of the plate E when the bolt
18 retracted, its shoulder e' meeting the edge of the plate E, the head of the empty
shell being thus left engaged by the claws of the extractor a little distance in front

page_text: of the face of the bolt in position to be ejected as will presently be described. As
the plate E retreats, its inclined edge acts upon the tail of the tumbler T thus
turning it partly round into position ready to again lock the bolt when it is advanced
to its forward position, the retreat of the extractor being also thus retarded.
The cartridges H are held in clips upon a belt H' which can travel over a curved
guido C fixed on one of the side covers (9. A lever having its ends engaged
with studs on the slides S' S' has a centre pin h³ engaged in a gab, wider than
itself, of a lever Figs 14 and 15; thus when either of the slides S'S' moves
back in recoil, the centre pin is moved back half the distance of the slide.
In the last part of its stroke in each duection it causes the lever to oscillato
On this
thus causing a sliding plate h (Figs. 7 and 16) to reciprocato vertically.
plate are mounted spring pawls which in the downstroke of the plate catch on the
back of the chips on the belt and thus move the bolt downwards a distance equivalent
to the interval between two clips By this movement successive cartridges are
brought into position to be fed to both barrels, the belt being held after each move-
ment by spring pawls 4 and 7 on the guide C, the upper ones of which prevent
the belt from moving too far forwards, and are released by the next ascent of the
plate The interval between the clips 15 so related to that between the baire's
that there is always one chip (or it might be another odd number) of chips between
the barrels
As shown in Figs. 4 and 16 there is for each barrel a feed lever K' K' both
pavotted at in the cover C which carries the bolt guide C. When the bolt D'
eaches its rear position as shewn in Figure 4 it acts on the tail 2 of the lever K'
causing two arms &³ on the front of the lever, which, as shown in Fig 7, extend
behind the feed belt to advance towards the barrel from the dotted position which
they previously occupied. As they do so, they push a cartridge out of a clip of the
belt into position in front of the bolt D by this action throwing out the empty
cartridge shell which was previously lying in front of the bolt between the jaws of
the extractor The shell, or it might be a miss fire cartridgo, is ejected through an
opening which has in its front part a sloping shoulder against which the bullet of
the fresh cartridge is held down by the arm Fig. 4 while the head of the
cartridge is pressed against a shouldor 40 by the arm k³, the fresh cartridge being
thus prevented from following that which is ejected.
As the bolt D advances to push the fresh cartridge into the barrel it first drivos
the flange of the cartridge against the claws of the extractor, thus directing the
cartridge straight into the barrel, a spring (Fig. 4) starts the movement of the
lever K back towards the position shewn in dotted lines, but its movement to that
position is completed by an arm A projecting from a plate k', which, being engaged
on a pin of the lever C, advances along with the bolt D2 and acts on a projection A
of the lever K pushing the lever to the dotted position and retaining it there while
the bolt is in its forward position.
Buffer springs & form elastic stops to the slides S S in the recoil, and other
buffer springs form similar stops to the lovers L
Each of
The firing of a charge is effected in the following manner. On the rear end of
the frame F are pivotted side by side two levers X' X', with a third lovor X³
between them. Either of tho levers X'X' can be pushed forward separately by
hand, or when X³ is pushed forward it pushes both X1 and X' forward
the levers X X has its lower end engaged with a sliding rod x' x* respectively.
When the levers X'X' and the rods are in the positions shown, toes on the
ends of the rods are so far forward that when the bolts D' D are in their
most forward position closing the barrels the sear levers do not roach the toes.³.
But when either of the levers X'X' is pushed forward to the position indicated by
the dotted lines in Fig. 3, then its rod or a being thus retracted, the toe on that
rod comes in the way of the sear lever p' thus causing it to release the striker and
fire the charge. The firing of either charge is thus made dependent on the lever ✗¹
or X being pushed forward, and when both aro pushed forward-by-X³, firing goes
on automatically. x is a safety catch which turned in one-position prevents the

page_text: lovers XXX from being pushed forwards, when turned in another position it
leaves them free to be pusled for wards and so permit firing, and in that case hooks
at the end of a spindle moving with engage the covors preventing them from
being turned down.
Besides the studs Fig. 1 there are on the opposite sides of the slides S¹ S² a
pair of studs 2 and, on the frame Fat I pivot a lever Z Figs 18 and 19
which has pivotted on it a sway beam Z' bearing against both the studs and ³.
The upper end of the lever Z carries a roller which bears against the periphery of
a cam This cam is pivotted in the left side cover C and can be turned by a
handle (Fig B) projecting outside the cover. By turning the handle Z and
thereby the cam in the direction of the arrow, the lever Z is moved to the
position shewn in Fig 19 retracting the sway beam Z' so that it pushes backwards
whichever of the studs a¹ is on the slide S¹ or S' that is then free to iccoil.
Thus the recoil movement can be effected by hand and all the operations resulting
from that movement can thus be performed without actual firing, as is necessary for
starting the automatic action of the gun In order that only that of the slides S'
or S2 which is in firing position with its bolt locked can be rotracted by hand as
above described, I provido a pair of boll crank catches and both on one
spindle pivotted in the framing F such that when the one is in the position shewn
in Fig 3 engaging a notch in the slide S' and preventing that slide from recoiling
the other catch Fig. 2, is in a position leaving the elido S¹ free to recoil. As
will be seen in Fig 1, when the bolt D¹ is advanced to its completely locked
position its shoulder d acting against one aim of the catch a moves that catch so as
to release the slide S' and to lock the slide S'
Instead of connecting the lever L to the bolt D' or D2 by a square or roller
working between shoulders d, I may connect the lever and bolt as shown in Fig. 20
by a link made with a nose which acts against an arm P' of the striker, to effect
the partial cocking on recoil after firing, the full cocking being effected on
withdiawal of the bolt, thus dispensing with the lover P which acts in the
notch of the striher, and also with the projections pl and p which operate
upon P.
I am aware that Palonts have been taken for automatic machine guns with one,
more barrels having then loading and firing mechanisms operated by
recoil I therefore make no general claim to a duplex machine gun operating in
two or
this manner.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what 1
claim 19 -
1. A duplex automatic machine gun in which the recoil of the one of two
barrels unlocks its own breech bolt and starts extraction of its fired case, and at
the same time ejects the fired caso from the other barrel, reloads it and locks its
bolt, substantially as described with reference to the accompanying drawings.
2. In the mechanism of the duplex automatic machine gun above referred to the
combination of the two barrels each with its bolt slide and advancing spring,
with the two levers L, arranged to operate alternately substantially as above
described.
3 In the mechanism for each barrel the combination of its breech bolt, locking
tumbler and suiker arranged and operating substantially as described
4. In combination with a belt provided with chips carrying cartridges, the duplex
cartridge ejecting and feeding mechanism, substantially as described.
Dated this 1st day of August 1805
ABEL & IMRAY,
Agents for the Applicant.