Year: 1899

page_text: Date of Application, 14th Apr., 1899
Complete Specification Left, 17th Oct., 1899-Accepted, 24th Feb., 1900
A communication from abroad by FRANCIS JOY HAESELER, a Lieutenant in the
United States Navy, and on duty at the Washington Gun Factory, Wash-
ington, D.C., United States of America.
I, PHILIP MIDDLETON JUSTICE, of 55 and 56, Chancery Lane, in the County
of Middlesex, Fellow of the Chartered Institute of Patent Agents, do hereby
declare the nature of this invention to be as follows:-
My invention relates to a mechanism for opening and closing the breech of a
breech loading gun, which mechanism consists essentially of two parts; a breech
plug, with its seat in the screw box of the gun, and mechanism for rotating said
breech plug to unlock the same, for swinging the same to the rear out of the
way, and for returning the same to the locked position.
As incidental details of the improvement I include the hinged carrier with
mechanism carried there by for first rotating the said block to unlock the same
and for removing the block a short distance rearward longitudinally; also
mechanism carried by said hinged carrier for firing the gun either by electricity
or by mechanical means, part of the firing mechanism being mounted on the
breech of the gun.
The principal feature of my invention consists in providing a breech block.
substantially conical in general shape but having its engaging surface divided
up into a series of spiral steps on each of which steps continuous spiral screw
threads are cut the screw threads on one spiral merging into those on the next
spiral, so that in reality each screw thread is of the form of a spiral wound
around the frustum of a cone.
These spiral steps and screw threads thereon engage corresponding steps and
screw threads in the breech of the gun and by this arrangement it will only be
necessary to turn the breech block through a comparatively small angle about
its axis so as to have all the threads on the breech block engaged with all the
threads in the screw box, and since each of these threads is continuous, an engage-
ment of all the threads on the block is had with all the threads on the screw box,
thus insuring great strength and enabling a lighter block to be used.
I am aware that breech blocks have been constructed in which a single spiral
thread or a single series of spiral threads is cut on the outer surface of the frustum
of a cone, such for instance as are shown in the specification to British Patent
to Silverman & Dawson, Number 1550, dated January 19, 1898, but this arrange-
ment lacks the series of spiral steps found in my invention, with the threads cut
on these steps, and therefore requires to be turned through a considerably larger
angle than with my invention, to lock or unlock the same, thus occasioning a
loss of time which is of critical importance in a modern rapid fire gun.
With my improved breech block housing therefore, it is possible to lock or
unlock the block by simply rotating the same through an angle of less than 90
degrees, when the block will be in position to be withdrawn to the rear, but in

page_text: practice I prefer to make the slope of the spirals and of the screw threads less
steep and to allow the block to lock and unlock after turning about 180 or
270 degrees.
For convenience in manufacture it is preferable to have the threaded spiral
block engaged in a screw box or housing which is itself substantially cylindrical, 5
with screw threads on its exterior to engage in screw threads of the gun body
whereby the said housing is held in. place.
Where the gun is built to fire fixed ammunition, an extractor is pivoted in the
walls of the gun or. in, the, plug itself, to engage, the rim of the cartridge case
and said extractor is or may be operated by the motion of the breech mechanism, 1
but where fixed ammunition is not used, the extractor. may be omitted.
The hinged carrier is hinged to the side of the gun in the ordinary way, and
carries on its forward portion a substantially cylindrical hollow boss which is
screw threaded on its exterior and engages a screw threaded sleeve secured in the
rear face of the breech block, and as the breech block is rotated to lock or unlock
it moves forward or backward in the said screw threaded sleeve, and thus brings
the spirals of the breech block clear of the spirals in the screw box so that the
breech block is in position to swing out of the screw box when the said breech
block is rotated to the unlocked position.
The breech block may be rotated in any convenient way, but I prefer the
hereinafter described method invented by me for this purpose, that is the breech
olock is provided with a rearwardly projecting stem projecting through the
hollow boss on the front of the hinged carrier, which stem encloses the firing
pin. Fast on this stem is a segmental pinion, which engages a rack which slides
in a guide-way in the hinged carrier and which rack is moved by a link secured
to the hand-lever near its pivot on the hinged carrier, whereby. I provide a
toggle joint of great power at the beginning and end of the stroke, and of con-
siderable speed as it nears the opening position. This enables the block to be
locked and unlocked on its seat with great force, while considerable speed is
secured during the rest of the motion of rotation of the block.
The teeth of the segmental pinion are interrupted by a lug which projects
beyond the outer edge of the teeth and engages one end of the rack when the
breech block is in the closed position, and the other end of the rack. when the
breech block is in the open position, the number of teeth on the segment thus
corresponding with the number of teeth on the rack so that the segment will
roll just the length of the rack. By having this engagement between the
end of the rack and a projection beyond the teeth of the pinion, a longer lever arm
is secured on said pinion to start the block from its locked position, and moreover
the great strain exerted at this time is imposed on a heavy lug instead of on the
lighter teeth of the segment so that there is no likelihood of injury at this time
either of the segment or of the rack.
The hand lever is pivoted on the hinged carrier near the pivot of the latter
and when the breech block has been turned to the fully unlocked position the
further motion of the block is arrested by the opposite end of the rack striking
the opposite side of the lug on the pinion aforesaid, and the whole system, hand 4
lever, hinged carrier, and parts carried thereby. swings as one mass about the
pivot of the hinged carrier, and as this hinged carrier with the weight of the
parts carried thereby swings forward, a lug or cam on the hinged carrier engages
a corresponding lug or cam on the outer arm of the extractor operating the same
and ejecting the empty cartridge case.
As a safety attachment and in order to lock the breech block in the screw box,
I provide a sliding bar which travels in a recess in the hinged carrier and extends
into a recess partly in the screw box and partly in the breech block, when the
breech block is in the closed or locked position. Or this sliding bar may be
replaced by a curved prong on the handle which is struck in the arc of a circle
whose center is the pivot of the handle, which prong projects through the carrier
and engages the screw box and the breech block.

page_text: To prevent wear on the parts, the engaging faces may be protected by a
hardened steel lining, but this is not necessary and may be omitted if desired.
The operating handle for the breech mechanism is connected to this locking
bar by a spring catch, which spring catch rides down an inclined face on the
hinged carrier as the handle is moved from the closed toward the opened position,
and before the toggle joint has had any appreciable effect in rotating the breech
block, the handle becomes disengaged from said locking bar but after having
withdrawn the same sufficiently to allow the breech block to rotate in the screw
box.
The carrier is locked to the gun until the breech block is rotated far enough
for the spirals of the block to swing clear of the spirals on the screw box, at
which time the hinged carrier is unlocked from the breech of the gun and is
free to swing outwards. This may be accomplished in many ways well known in
the art, but I prefer to do this by means of a lug on the breech block which
strikes a cam arm on a sliding pin or spring catch mounted on the carrier and
sliding in and out thereon.
The lug on the breech block strikes this cam arm near the end of the motion
of unlocking of the breech block and withdraws the said spring catch from en-
gagement with the breech of the gun, releasing the hinged carrier from the gun
and allowing the same to swing outwards.
As the hinged carrier begins to swing open, a spring-operated catch slips over
the lug on the breech block and locks the same against backward rotation in the
carrier, so that when the breech block is swung back again in the screw box for
closing the breech, the threads and spirals will be held in the engaged position.
The firing mechanism is mounted partly in the hollow stem projecting to the
rear from the breech block, partly in the hinged carrier at right angles to said
stem, and partly on the breech of the gun, and the principal feature of the firing
mechanism devised by me is the ready means by which the same may be con-
verted from mechanical firing to electric firing or the reverse. In order to do
this it is not necessary to remove any of the parts of the mechanical firing
mechanism, but by pulling on the trigger and drawing up the sear and then lock-
ing the sear by a screw in the withdrawn position, the parts are then ready for
the electrical connection. This is already provided at the side of the gun in an
insulated binding post, an electrical conducting rod normally pressed forward
by a spring in electrical connection with said binding post, an insulated con-
ducting stud passing through the locking bar and connected with another con-
ducting strip which leads to the firing pin, the several parts being necessarily
insulated.
By having this conducting strip mounted in or insulated from the locking
bar and so arranged that the electrical_connection will only be made when the
locking bar is in the locked position, it will be impossible to fire the gun by
electricity except when the breech is closed and locked.
The firing pin itself is insulated, and when in the position for electric firing,
the point of the firing pin projects through the hole in the nose of the breech
block and bears against the electric primer, but since this hole is somewhat
larger than the point of the firing pin, there will be an annular space filled with
air surrounding the point of the firing pin which will form a suitable insulation
at this point, the greater portion of the current being through the better con-
ducting parts of the primer.
The mechanical means for firing the gun consists of a spring operated firing
pin which is also insulated for use with the electrical firing mechanism, as before
stated. The firing pin is also provided with shoulders engaging the end of the
stem of the breech block when in the forward firing position, and as the breech
block is moved rearward on the carrier during the operation of unlocking, the
firing pin is also withdrawn rearward until a spring operated sear projects
through an opening into said stem and engages in front of said shoulder and
holds the firing pin when the breech block is brought back to the locked position.

page_text: This sear is in engagement with a spring operated sliding bar which is drawn
outward by means of the trigger, which trigger is secured to the breech of the
gun. The sliding bar last referred to is provided with a transverse groove in
which the locking bar is free to slide and thus the locking bar holds the sliding
bar until the the shoulder and the rear end of the locking bar passes beyond the said
sliding bar, this at the time when the breech block is locked in the gun. At this
time the sliding bar may be drawn outward, releasing the sear, but at all other
times the sliding bar is set against longitudinal motion by the locking bar, and
hence it will be impossible to release the sear by means of the trigger except when
the breech is closed and the breech block locked therein.
The rear end of the firing pin may be provided with a detachable handle for
cocking by hand if desired..
141
C
1000
A communication from abroad by FRANCIS JOY HAESELER, a Lieutenant in the
United States Navy, and on duty at the Washington Gun Factory, Wash-
ington, D.C., United States of America.
I, PHILIP MIDDLETON JUSTICE, of 55 and 56, Chancery Lane, in the County
of Middlesex, Fellow of the Chartered Institute of Patent Agents, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:―
My invention relates to a mechanism for opening and closing the breech of a
breech loading gun, which mechanism consists essentially of two parts; a breech
plug, with its seat in the screw box of the gun, and mechanism for rotating said
breech plug to unlock the same, for swinging the same out of the way, and for
returning the same to the locked position.
As incidental details of the improvement I include the hinged carrier with :
mechanism carried thereby for first rotating the said block to unlock the same
and for swinging the block a short distance out of the way; also mechanism
carried by said hinged carrier for firing the gun either by electricity or by
mechanical means, part of the firing mechanism being mounted on the breech
of the gun.
I also provide means operated by the hand lever or the equivalent part for lock-
ing the block against turning in the screw box when the breech mechanism is in
the firing position.
The principal feature of my invention consists in providing a breech block
substantially conical in general shape but having for its engaging surface a
single flat spiral forming a series of spiral steps, on each of which steps continu-
ous parallel spiral screw threads are cut. all of the threads being of the same
diametral and axial pitch, so that in reality each screw thread is of the form of
a spiral wound around the frustum of a cone.
These spiral steps and screw threads thereon engage corresponding steps and
screw threads in the breech of the gun and by this arrangement it will only be
necessary to turn the breech block through a comparatively small angle about its
axis so as to have all the threads on the breech block engaged with all the threads
in the screw box, and since each of these threads is continuous, an engagement

page_text: of all the threads on the block is had with all the threads on the screw box, thus
insuring great strength and enabling a lighter block to be used.
My invention will be understood by reference to the accompanying drawings,
in which the same parts are indicated by the same letters throughout the several
views.
'
Figure 1 is a rear view of the breech of the gun, with the breech closed.
Figure 2 represents a section along the line 2-2 of Figure 1 and looking down
the breech block being shewn in plan, as also the cartridge case.
Figure 3 is an elevation of the breech of the gun, with the breech closed, and
with the hinged carrier broken away to shew the mechanism for rotating the
breech block about its axis, and for locking the same in the hinged carrier when
the screw threads on the block are disengaged from those in the screw box. It
also shews the mechanism for locking the hinged carrier to the gun.
Figure 4 represents a section along the line 4 4 of Figure 3 and looking
down, the breech block and parts carried thereby being omitted to better illus-
trate the screw box and operation of the hand lever.
Figure 5 is a rear view, on an enlarged scale, of the breech block as detached
from the carrier.
Figure 6 represents a side elevation of the breech block removed from the gun
and shews the carrier in section along the line 6-6 of Figure 1, and looking to
the right of the said figure.
Figure 7 is a front view of the breech block as detached from the gun.
Figure 8 represents a section along the line 8-8 of Figure 6 and looking down.
Figure 9 represents a rear view of the hinged carrier, with the various other
parts of the breech mechanism omitted.
Figure 10 represents a plan view of the hinged carrier partly in section along
the line 10-10 of Figure 14.
Figure 11 represents a plan view of the threaded sleeve by means of which
the breech block is connected to the hinged carrier.
Figure 12 represents a rear elevation of the screw threaded sleeve shewn in
Figure 11.
Figure 13 represents an inverted plan view of the stop lug for the hand lever,
which lug is secured to or made integral with the hinged carrier.
Figure 14 represents a front view of the hinged carrier as detached from the
gun, but with the breech block omitted.
Figure 15 represents an end elevation partly in section along the line 15-15
in Figure 14.
:
Figure 16 represents a section along the line 16-16 in Figure 14.
Figure 17 represents a section along the line 17-17 in Figure 14.
Figures 18, 19 and 20 are detail views shewing the housing, in which are
mounted the sear and the sliding bar for operating the same, Figure 20 being in
section along the line 20-20 in Figure 18.
Figures 21 and 22 are detail views of the sear.
Figures 23, 24 and 25. represent the sliding bar for operating the sear.
Figure 26 represents a rear elevation and Figure 27 a plan view of the hand
lever for operating the breech mechanism.
Figure 28 represents a section across the hand lever along the line 28-28
in Figures 26 and 27.
Figures 29 and 30 are detail views of the catch for connecting the locking bar,
or safety device, to the hand lever.
Figure 1 represents a side elevation of the locking bar for locking the breech
block against rotation in the screw box when the breech is closed.
Figure 32 represents a section of the locking bar along the line 32-32 in
Figure 31.
Figure 33 represents the details of the electrical connections for firing, the
same being a section along the broken line 33-33 of Figure 34.

page_text: Figure 34 represents the electrical connections for firing, the same shewing
a section along the broken line 34-34 of Figure 33, and
Figure 35 represents a modification in which the breech block is locked in
the screw box by a tongue or arm projecting forward from the hand lever.,
The drawings are intended to illustrate the invention in the form at present
preferred by me, although many changes might be made without departing from
the spirit of my invention.
A represents the body of the gun, which may be either itself screw-threaded for
the screw box as shewn at A2, or a housing A may be screwed into the breech of
the gun as at a and may carry on its interior the screw-threads of the screw box.
These screw threads are arranged on the surface of one continuous spiral form-
ing a series of spiral steps A2, on each of which steps are screw threads a³, which
screw threads register with the screw threads 2 on the spiral steps B2 of the
breech block B. Each of these threads on the breech block and also in the screw
box, is a continuous spiral, and if considered alone would be found in the form
of a spiral thread wrapped around the frustum of a cone, thus when the breech
block is locked in the screw box, all the threads on the breech block are in
engagement with the corresponding threads on the screw box, and thus great
strength is secured.
The gun body may be provided with ears A³ for the pivot bolt, and with a
recess A° for the extractor in case the gun is to be fitted to fire fixed ammunition.
The breech block is mounted on the hinged carrier C, to which it is revolubly
connected as will now be described.
A sleeve B is screwed into an annular recess in the rear face of the breech
block and on the inside of this sleeve are coarse screw threads b¹ engaging coarse
screw threads. on the annular boss 12 of the sleeve D. The pitch of the
thread and is such that rotation of the breech block to the un-
locked position will draw the breech block to the rear relative to the carrier,
while the corresponding rotation of the breech block to the locked position will
force the breech block forward a like distance, in each case the breech block is
so moved that the screw threads 62 on the breech block will be in proper position
to engage the screw threads a² of the screw box when the hinged carrier is swung
against the face. of the breech. As soon as the threads 62 and a² become dis-
engaged, the breech block is supported by the boss D³ and threads (2.
I preferably use a sleeve B¹ screwed into the rear of the block to avoid wear,
and facilitate construction of the parts, but it will be obvious that these, screw
threads 61 may be cut directly into the block itself instead of the sleeve B¹, thus
this sleeve may be omitted if desired.
Where a sleeve B¹ is used it may be locked in place in any convenient way, as
by the spline screw 6. see especially Figure 8..
The sleeve D, see Figures 3, 6 and 11, is provided with a segmental rib d
and the said sleeve is secured to the face of the hinged carrier by means of the
bolts d, passing through the holes in the hinged carrier.
Projecting to the rearward from the breech block is the hollow stem B', which
passes through the sleeve D and projects into a cylindrical recess in the hinged
carrier C. This stem serves as a journal for the breech block and also as a
casing for the firing pin, as shewn in Figure 8.
A block B, see Figures 6 and 8. may be let into the side of the breech block
and provided with a recess b for the locking bolt M, as will be hereinafter de-
scribed, and the said block if used should be made of hardened material, to prevent
wear, but if preferred this block. B³ may be omitted and a recess 65 may be cut
into the body of the breech block itself.
The breech block is rotated about its axis so as to lock and unlock the threads b
and a, by means of the segmental pinion K. the rack H. the link H¹, and the
hand lever F, which is pivoted to the hinged carrier and the block G carried by
the same.
The hand lever F is provided with a handle F1 at one end thereof
and is pivoted at the other end to the bolt F2 supported by the hinged carrier C.

page_text: This bolt 2 projects through the opening Gº, see Figure 13, in the block G,
which block is secured to the carrier C is any convenient way. This block is
under-cut and provided with a shoulder g,'against which the hand lever F strikes
when the said hand lever has reached the limit of its outward travel, as indicated
by the dotted lines numbered 3 in Figure 4. This block is made separate from
the carrier C merely for convenience of manufacture and may be integral with
the said carrier if preferred.
The link H' connects the hand lever F with the rack H, which rack travels
in the guide-way Co, see Figures 6 and 14, in the hinged carrier C, and is held
in place by the feather . The said rack meshes with the teeth k of the segmental
pinion K, and this segmental pinion has a key which travels in a slot on the stem
of the plug so as to allow the latter to slide through it as the plug moves longi-
tudinally to the rear, due to the pitch of the screw, but rotates with the plug.
The pinion is provided with a sector projecting beyond the ends of the
teeth, and so arranged that when the breech block is locked in the screw box,
one side of this sector bears against one end of the rack H below the teeth of
the latter, while when the breech block is open or unlocked from the screw box,
the other end of this segment bears against the opposite end of the rack and
engages.below the teeth of the same. In this way the heavy starting strain of
unlocking the breech block, upon the mechanism just described, is transferred
from the comparatively weak teeth of the sector K and the rack H to the solid
segment and the end of the rack, and thus it will be impracticable to injure
either the rack or the sector should the strain of starting the block be excessive.
In the same way the heavy strain of the initial movement of the block towards its
locked position is brought upon the opposite end of the rack and sector.
This sector K is secured on the stem B in any convenient way, as by means
of the feather 2, preferably dovetailed, as shewn in Figure 3.
When the breech block is locked in the screw box, the rack H will be in the
position shewn in Figures 3 and 4, with the end of the body of the rack H bear-
ing against one side or the segment, as shewn in Figure 3, at which time the hand
lever, broken away in Figure 3, would be in the position indicated by the
dotted lines 1. in Figure 4.
Now if the hand lever be drawn to the rear, the link H¹ would combine with
the shorter arm of the hand lever to form a toggle joint which would start the
rack very slowly, but under great power, and would consequently give a slow but
powerful wrench to the breech block to unlock the same. As soon as the hand
lever has passed the position indicated by the dotted lines at 2. in Figure 4,
the teeth of the rack will begin to engage the teeth of the sector K, and the
position of the toggle joint will enable a quicker velocity of rotation to be im-
parted to the breech block. Finally when the hand lever reaches the position
indicated by the dotted lines at 3 in Figure 4, the opposite end of the segment kl
will strike the outer end of the rack H, checking the further rotation of the breech
block, at the same time the hand lever will bring up against the shoulder 7 of
the block G, and the hand lever and the carrier C, as well as all the parts
carried by the said carrier will swing as one mass about the bolt E until the breech
mechanism is in the open position and the gun may be loaded.
In order to lock the breech block in the carrier after it has become disengaged
from the screw box, any well known locking device may be provided, but I
prefer the form of device hereinafter described.
B is a stud which is secured to the rear face of the breech block, which is
rounded on two sides and provided on the opposite sides with flat faces, one of
which is indicated by 67.
Q represents a spring plunger or latch having the cam arm g; see Figures 3
and 14, projecting upwards and inwards, and the holding lug g, which lug
engages in a recess either in the gun body or in a plate or housing W secured to
the gun body when the breeches is closed. This lug. q is normally pressed
outwards by means of the spring When the breech block is rotated to

page_text: the unlocked position, the lug B6 engages, the cam
arm 9 and withdraws
the latch Q, releasing the lug g₁ from engagement with the gun body,
and allowing the hinged carrier to be swung outward. As the hinged carrier
swings back, the inclined face q of a second plunger or catch Q slides along
the inclined face 18 of a lug Q2 fast to the gun body, see
.
When
Figure 10,
and the shoulder g of this catch Q projects over the face of the lug 136, and
thus locks the breech block against rotation backwards in the hinged carrier, so
long as the hinged carrier is clear of engagement with the breech of the gun.
This spring catch Q' has a limited motion in guide ways in the hinged carrier C,
as indicated in Figure 15, and is normally pressed back by the spring q';
the hinged carrier is swung forward to the closed position, the lug Q2 projects into
the opening in the spring catch Q', and the cam face q engages the cam
face causing the catch Q to be drawn outward until the shoulder q is clear
of the flattened face of the stop 13. At this time the breech block will be ready
for rotation to the locked position, and the motion of the hand lever from the
position 3 to the position 1, see Figure 4, will rotate the breech block, causing
the screw threads to engage the screw threads a². As soon as the lug 136
passes clear of the cam arm of the latch Q, the latter will move outwards and
lock the hinged carrier to the gun body. Thus it will be seen that by a simple
motion of the hand lever in one direction the breech block is unlocked from the
screw box, is locked on the carrier, and the latter is unlocked from the gun and
is swung outward until the breech is open, while a motion of the hand lever
in the reverse direction will reverse this cycle of operation and will close the
breech.
In order to prevent any rotation of the breech block in the screw box, due to
the pressure of the gases when the gun is fired, and also to prevent premature
discharge, I provide an auxiliary lock, which will now be described.
M represents a sliding bar having a rounded head M and traveling in a
suitable guide way in the hinged carrier. This head projects into the
recess either in the breech block B, or in the wear block B set in the breech
block, as has been described, and as shewn in Figures 5, and 8. This block
may be secured in place in any convenient way, as by means of the screw 66,
see Figure 5. The outer side of this head engages in a corresponding recess in
the gun body, and thus this sliding bar M serves as a feather or spline engaging
partly in the breech block and partly in the gun body, and locks the breech
block firmly against rotation when this sliding bar is in the forward position
as indicated in Figure 2. The corresponding recess in the gun body may be made
either in the gun body itself, in the housing A' or in a separate wear block A³
let into the housing A¹, as shewn in Figures 2 and 4. In case a separate block
be used, this should preferably be made of hardened material similar to the
block B already described in connection with the breech block.
The sliding bar M is withdrawn by the first motion of the hand lever rearward
in opening the breech, and is pressed home by the last motion of the hand lever
in closing the breech, that is, it is withdrawn when the hand lever moves from
the position indicated by the dotted lines 1, to that indicated by the dotted lines 2
in Figure 4, and the reverse in closing, during which there is no rotation of the
block due to the location of the centres of the toggle-joint motion, and some very
little lost motion.
In the modification shown in Figure 35, instead of the sliding bar M, an
arm F3 is shewn projecting forward into the curved slot partly in the breech
block and partly in the screw box, which curved arm is on a radius struck with
a centre F2, and it will be obvious that when the hand lever is drawn to the rear,
as indicated in dotted lines in Figure 35, that the engaging arm F3 will be with-
drawn from engagement either with the screw box or with the breech block, and
that the latter may turn in the screw box, and, therefore, the modification shewn
in Figure 35 illustrates the simplest form of spline adapted to lock the breech
block against rotation in the screw box; but in the other device the sliding bar M

page_text: is moved longitudinally during a short portion only of the travel of the hand
lever, and how this longitudinal motion of the sliding bar is effected will now be
described. But as the sliding bar M also serves as a safety device to prevent
the gun from being prematurely fired, it had best be described in connection with
the firing mechanisni, by means of which the gun may be fired either by mechani-
cal means or by electricity.
Since it is desired to rapidly substitute the electric for the mechanical firing de-
vice, and vice versa, I preferably construct these parts so that the substitution may
be made with as little change as practicable. With this end in view certain of the
operative parts are insulated, as shewn in Figures 8 and 31 to 34 inclusive.
R represents the firing pin having the point projecting through the open
hole in the nose of the breech block, the point of which pin is made somewhat
smaller in diameter than the said hole and concentric therewith, so that when the
pin strikes the primer of the cartridge case there shall be an annular space filled
with air interposed between said pin and the conducting material of which the
breech block is composed. Insulated from this firing pin R is the sleeve R³,
which travels in the recess 130 in the stem B of the breech block, and this sleeve
and the firing pin contained therein are normally pressed forward by means of
the spring, which is held against rearward motion by means of the insulated
cup held in the cap et secured in the boss projecting from the rear of the
hinged carrier. To the rear end of the firing pin I preferably secure the shank R'
having the handle R2 for cocking by hand if desired, but this is unnecessary,
and may be omitted without disturbing the electrical circuit.
The sleeve R has an annular shoulder to engage the sear S, which is nor
mally pressed towards the firing pin by means of the coil spring St. The sear
is also provided with a small recess s in which the point of the screw s may
be made to project and thus lock the sear in the rearward position out of en-
gagement with the annular shoulder, when it is desired to fire by electricity.
From an inspection of Fig. 8, it will be seen that as after the gun be fired the
firing pin will plunge forward and remain in the forward position until the
breech block be turned to unlock the same from the screw box, then the block
and firing pin will be moved bodily backwards by the screw threads and d
until just as the breech lock approaches closest to the hinged carrier, the sear
snaps under the annular shoulder on the firing pin, and holds the same cocked
during the return of the breech block to the locked position, thus the firing pin
is automatically cocked, and is released only when the sear is withdrawn.
T represents a sliding bar having a shoulder t engaging the sear for drawing
the latter to the rear as in firing the gun, which bar is normally pressed forwards
by means of the spring bearing at one end against a shoulder of the said bar
and at the other end on a fixed stop 2. The sear and sliding bar T are mounted
in the housing P, see Figures 8 and 18 to 20, which housing is provided with
ribs to engage in guide ways in the rear face of the carrier, see Figures 9
and 15, and the inward motion of this housing P is limited by the vertical face c³,
see Figures 9 and 15.
The rear end of this bar T terminates in a hook to engage the trigger U,
which is drawn back by means of the cam face of the wedge block V engaging
the cam face of the trigger U. This trigger is normally pressed inwards by
means of the spring u, while the wedge block V is normally pressed rearward
by the spring, and is drawn forward by the firing lanyard, not shewn, engaging
in the eye Thus it will be seen that pulling forward on this eye will draw
the bar outward, drawing the sear S clear of engagement with the annular
shoulder of the sleeve R and releasing the firing pin, which springs forward
under the action of the spring.
The trigger U and block V are preferably mounted in the housing W, which
may be left open to the rear as at w for convenience in assembling the parts.-
This housing W is connected to the gun body in any convenient way, and is
provided with a binding post w³ connected to the metal block at one end of

page_text: the conducting plunger ¹, see Figures 33 and 34, which plunger is normally
pressed against the conducting strip, which bears against the spring distended
conductor M² mounted in the locking bar M, which makes contact when the breech
is closed and locked by means of the strip with the conducting screw and
the insulated cup in contact with the spring, and thus electric connection,
insulated from the gun body and the parts connected therewith, is provided
between the binding post 2 and the firing pin R. The sliding bar T is provided
with a lugt to engage the back of the sear, with an opening to receive the cross
piece against which the spring t¹ bears, and with a groove to in which the
locking bar M travels when not in the locked position. Thus the locking bar
is drawn at right angles to the bar T and in a groove therein, and prevents this
bar from being moved and consequently prevents the gun from being fired by
mechanical means, except when the locking bar is in the forward or locked
position. When in this position the shoulder m' on the locking bar clears the
bar T, see Figure 6, and the said bar T is free to move longitudinally.
.
The spring distended contact M is mounted in the opening m² in the bar M,
see Figure 32, and is insulated from said bar, and this contact M² is so arranged
that it will make connection between the conducting strips and only when
the bar M is in the forward or locked position. If it be out of this position,
any current from the binding post would pass through the body of the bar M
to the hinged carrier and thence to the gun without making the circuit through
the electric primer, but when the parts are in the position shewn in Figure 34,
the current from the binding post will pass through the conductors a,,, M²,
and to the insulated cup, thence to the firing pin R and through the point
of the firing pin, which, as has already been stated, is insulated from the sides
of the hole by means of the surrounding air, to the electric primer, thus the
gun may be fired by electricity only when the locking bar Mis in the forward or
locked position. When firing by electricity, the sear is held back by the screw s¹..
Having thus described the cooperation of this locking bar M with the firing
mechanism, I will now describe the means by which the bar is moved, backward
from the locked to the unlocked position, and is returned. forward from the un-
locked to the locked position automatically by the hand lever.
Referring now to Figures 6 and 29 and 30, N represents a spring catch having
the cross-head n adapted to engage the cam surfaces and p of the housing P.
This catch is provided with a shank and a nut n² and is normally pressed
upwards or into engagement with the locking bar M by means of the spring N
mounted in a hollow boss f¹ on the hand lever.
Suppose the locking bar M to be in the position shewn in Figures 6 and 8,
and the hand lever to be started to the rear, the first motion of the hand lever
will draw the locking bar M rearward, at the same time causing the cross-head n
to ride down the cam face p² on the housing P, and thus will gradually disengage
the cross-head from the recess m in the locking bar M, until when the hand
lever reaches the position indicated by the numeral 2 in Figure 4, the cross-
head will be entirely out of engagement with the locking bar M and the hand
lever may be swung rearward without further disturbing the locking bar. At
this time the locking bar is drawn outof locking engagement between the
breech block and the screw box in the gun, and the breech block is free to rotate
about its axis. The first slight motion of the hand lever to the rear will be
insufficient to give any appreciable rotation to the breech block due to the location
of the centers of the toggle joint motion and therefore it will only be necessary
to provide very little lost motion between the end of the rack and the operating
face of the segment to enable the locking bar to be withdrawn sufficiently
far to the rear before the rotation of the block on its axis is begun. To prevent
the locking bar M from being too suddenly thrown to the rear and becoming
nisplaced, I provide a shoulder m² on the back of the locking bar, engaging a
corresponding shoulder pl on the housing P, see Figure 6, and thus the rearward
travel of the locking bar is limited.

page_text: It will be seen that in closing the breech, as the hand lever is swung from the
position marked 3 to that marked 2 in Figure 4, the cross-head n is brought into
contact with the cam face p of the housing P and further movement of the hand
lever causes the cross-head to ride down this cam until it passes on to the
cam 2, when the spring N1 presses the cross-head n upward projecting the
same into the recess m in the under side of the locking bar and causing this
cross-head to force the locking bar forward into the locked position, returning
the parts to the position shewn in Figure 6.
Thus it will be seen that the first rearward motion of the hand lever will
draw the locking bar to the rear out of engagement and then release the same;
leaving the hand lever free to continue its travel about its pivot F2 while in closing
the breech the last part of the movement of the hand lever will move the locking
bar into the forward or locked position. Since the gun cannot be fired until the
locking bar is in the forward or closed position, it will be seen that the last part
of the movement of the hand lever, after the screw threads 62 and a² are in com-
plete engagement, will be to move this locking arm forward and nut the parts
in such position that the gun can be fired. while the first part of the motion of
the hand lever in opening the breech will be to put the parts of the firing
mechanism in such position that the gun cannot be fired, and, therefore, the
locking bar M forms part of the automatic means by which the ordinary danger
from premature firing is absolutely eliminated.
Where it is desired to use fixed ammunition, the side wall of the gun may be
slotted as at A° for the insertion of the extractor I pivoted on the bolt
y and
having the rearwardly extending arm y¹ and the stop shoulder y, see Figure 2.
This extractor is operated by means of the cam plate Z made fast to the hinged
carrier, as by means of the stud, and is provided with a cam face and a
stop face 3, so that as the breech is swung open, there is a slow motion of the
extractor about its pivot to start the projectile, during which time great power
will be exerted, and after the cartridge case has once been released from its
seat the quicker motion of extracting is set up, the advantages of which are well
known in the art. Any other form of extractor may be used, preferably one
which is carried or actuated by the plug itself, so that the gun body need not
be cut at all. As soon as the hinged carrier has been swung far enough to the
the shoulder y brings up against the face of the gun and the block Z stops
the further outward motion of the carrier: but this outward motion may be
arrested in any other preferred way.
rear,
While I have described the invention in detail it will be obvious that many
of the parts may be changes in construction and many of the parts may be
wholly omitted, and that many structural changes may be made by any one skilled
in the art without departing from the spirit of my invention.
By having the bar M project into and lock the breech block against rotation, it
is possible to make the pitch of the screw threads greater, but any other suitable
means for holding the breech block against rotation may be adopted if desired,
or friction alone depended upon.
I am aware that breech blocks have been constructed in which a single spiral
thread or single series of spiral threads is cut on the outer surface of the frustum
of a cone, such for instance as are shewn in the British patent to Silverman &
Dawson, Number 1550, dated January 19, 1898, but this arrangement lacks the
series of spiral steps found in my invention, with the threads cut on these steps,
and therefore requires to be turned through a considerably larger angle than
with my invention, to lock or unlock the same, thus occasioning a loss of time
which is of critical importance in a modern rapid fire gun.
With my improved breech block housing, therefore, it is possible to lock or
unlock the block by simply rotating the same through an angle of less than
90 degrees when the block is in position to be withdrawn to the rear, but in
practice, I prefer to make the slope of the spirals and of the screw threads less

page_text: steep and to allow the block to lock and unlock after turning about 120 or 180
degrees.
While it is desirable, whenever practicable to have the parts subjected to wear,
lined or faced with hardened material, I do not mean to limit my invention to
such construction.
It will be evident that the engagement of the threads a² and 2 being continu-
ous, the great loss of strength incident to ordinary mutilation of the threads
of the breech block and of the screw box is avoided. and that far greater strength
with corresponding lightness of parts is secured. Moreover the threads 12 and a²
become engaged and disengaged almost simultaneously, and after the first act
of starting, all the friction of turning the block is transferred to the boss D³
and sleeves B¹ and B, until the block is brought back to the final position in
locking.
A feature of my invention is the facility by which the electrical firing mechanism
may be substituted for the mechanical, or vice versa, it being only necessary
to draw back the sear and run in the screw s¹ far enough to hold the sear back,
and the parts will be in position for electric firing: while if the screw s¹ be with-
drawn far enough to release the sear and allow it to be pressed against the
firing pin, the parts will be in position for firing by mechanical means.
Having thus particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, as communicated
to me by my foreign correspondent I declare that what I claim is:
1. The improved form of breech closure for guns arranged to give a complete
engagement of the continuous screw threads after the breech block has been turned
through considerably less than 360°, substantially as herein described and as
shewn in Figures 2, 4, 6 and 8 of the drawings.
2. The mechanism for rotating the block to lock and unlock the same, sub-
stantially as herein described and as shewn in the drawings.
3. A gun having a screw box and a screw breech block, with breech mechanism
operated by a hand lever, and a bar operated by said hand lever and projecting
into a recess partly in the block and partly in the screw box, whereby the block
is locked against possible rotation due to the pressure of the powder gases, sub-
stantially as herein described and shewn in the drawings.
4. The electric firing mechanism constructed substantially as herein described
and as shewn in Figures 2 and 31 to 34 of the drawings.
5. A breech block for use in breech loading guns substantially in the form
of a frustum of a cone in general shape, but having its engaging surface divided
up into a series of continuous spiral steps with a plurality of continuous screw
threads cut on each of said steps, substantially as herein described and shewn in
Figures 2, 4, 6 and 8 of the drawings.
6. A breech block for use in breech loading guns having its engaging surface
formed as if a ribbon wound in a spiral radially and longitudinally, so that any
section of said ribbon made by a plane passing through the axis of said block
would be parallel to said axis, with a plurality of screw threads cut upon said
ribbon, in combination with means for locking and unlocking said block and
for swinging it into and out of the breech of the gun, substantially as herein
described and as shewn in the drawings.
7. The improved safety device for locking the breech block against rotation
and for guarding against premature discharges, in combination with devices
operated automatically during the opening and closing of the breech for operating
said safety device, substantially as described, and for the purposes specified.
8. A gun, provided with my improvements in breech mechanism constructed
and operating substantially as herein described with reference to Figures 1 to
12 of the drawings.
9. In a breech loading gun, the combination with a breech block substantially
in the form of a frustum of a cone but having its engaging surface divided up into

page_text: a series of spiral steps, with a plurality of screw threads cut on each of said
spiral steps, of a screw box having corresponding threads engaging those of the
breech block, substantially as described and shewn in the drawings.
10. In a breech loading gun, the combination with a breech block substanti-
ally in the form of a frustum of a cone but having its engaging surface divided
up into a series of spiral steps, with a plurality of continuous screw threads cut
on each of said spiral steps, of a screw box having continuous threads similarly
arranged to and engaging those of the breech block, substantially as described.
11. In a breech loading gun, the combination with a breech block substanti-
ally in the form of a frustum of a cone but having its engaging surface divided up
into a series of spiral steps, with a plurality of continuous screw threads cut on
each of said spiral steps, and a screw box having continuous threads similarly
arranged to and engaging those of the breech block, of means for rotating said
breech block to lock and unlock the same, and for swinging said block into and
out of the gun, substantially as described and shewn.
12. In a breech loading gun, the combination with a breech block substanti-
ally in the form of a frustum of a cone but having its engaging surface divided
up into a series of spiral steps, each step being substantially rectangular in cross
section, with a plurality of screw threads cut on the exterior part of each of
said spiral steps, and a screw box having threads corresponding to and engaging
those of the breech block, of a hand lever and mechanism operated thereby, for
first rotating the breech block about its axis is unlocking, and then swinging the
same to the rear, or vice versa, substantially as described and shewn in the
drawings.
13. In a breech loading gun, the combination with a breech block substantially
conical in general shape but having its engaging surface divided up into a series
of spiral steps, with a plurality of screw threads cut on each of said spiral steps,
of a screw box having threads registering with those on the breech block, a hinged
carrier, a rack mounted on said carrier, a pinion held against rotation on the
breech block and engaging said rack, and a hand lever operating said rack and
hinged carrier, substantially as described and shewn in the drawings.
14. In a breech loading gun, the combination with a breech block substantially
conical in general shape but having its engaging surface divided up into a series
of spiral steps, with a plurality of screw threads cut on each of said spiral steps,
of a screw box having threads registering with those on the breech block, a
hinged carrier, a rack mounted on said carrier, a segmental pinion held against
rotation on the breech block and having a segment projecting beyond its teeth
and engaging the ends of said rack, and teeth engaging the teeth of said rack,
and means for moving said rack and for swinging said carrier, substntially as
described and shewn in the drawings.
15. In a breech loading gun, the combination with a breech block substantially
conical in general shape but having its engaging surface divided up into a series
of spiral steps, of a screw box having threads registering with those on the breech
block, a hinged carrier, a rack mounted on said carrier, a pinion held against
rotation on the breech block and engaging said rack and a hand lever operating
said rack and hinged carrier, with a locking bar engaging said block and holding
same against revolution in the screw box, when the breech is closed, substantially
as described and shewn in the drawings.
16. In a breech loading gun, the combination with a breech block substantially
conical in general shape but having its engaging surface divided up into a series
of spiral steps, with a plurality of screw threads cut on each of said spiral steps,
of a screw box having threads registering with those of the breech block, means
for rotating said breech block, and for withdrawing same from the screw box.
firing mechanism, and a combined locking bar and safety device engaging said
block and holding same against revolution in the screw box when the breech
is closed, and also interrupting the action of the firing mechanism at all times

page_text: except when the breech is closed and the locking bar in locking engagement,
substantially as described and shewn in the drawings.
.
17. In a breech loading gun provided with a screw box, of a breech block
having screw threads registering with those of the screw box, means for rotating
said breech block to unlock the same from the screw box, and means for with-
drawing the breech block from the screw box, firing mechanism, and a combined
locking bar and safety device engaging said block and holding same against
revolution in the screw box when the breech is closed, and also interrupting the
action of the firing mechanism at all times except when the breech is closed and
the locking bar in locking engagement, substantially as described and shewn in
the drawings.
18. In a breech loading gun, the combination with a breech block with screw
threads thereon, of a screw box having threads registering with those on the
breech block, a hinged carrier, a rack mounted on said carrier, a pinion held
against rotation on the breech block and engaging said rack and a hand lever
operating said rack and hinged carrier, with a locking bar operated by said hand
lever engaging said block and holding same against revolution in the screw box,
when the breech is closed, substantially as described and shewn in the drawings.
19. In a breech loading gun provided with a screw box, of a breech block
having screw threads registering with those of the screw box, means both for
rotating said breech block to unlock the same from the screw box and for with-
drawing the breech block from the screw box, firing mechanism, and a safety
device engaging said block and holding the same against revolution in the screw
box when the breech is closed, and also interrupting the action of the firing
mechanism at all times except when the breech is closed and the locking bar
in locking engagement, substantially as described and shewn in the drawings.
20. In a breech loading gun provided with a screw box, of a breech block
having screw threads registering with those of the screw box, firing mechanism,
a safety device engaging said block and holding same against revolution in the
screw box when the breech is closed, and also interrupting the action of the
firing mechanism at all times except when the breech is closed and the locking
bar in locking engagement, and means for first releasing said safety device, then
rotating said block to unlock the same, then swinging said block to the rear,
then cocking said firing mechanism, and finally returning the block and safety
device to the initial locked position, substantially as described and shewn in
the drawings.
21. In a breech loading gun, the combination with a breech block having screw
threads thereon, of a screw box having threads registering with those on the
breech block, a hinged carrier, a rack mounted on said carrier, a segmental
pinion held against rotation on the breech block and having a segment projecting
beyond its teeth and engaging the ends of said rack, and teeth engaging the teeth
on said rack, a hand lever pivoted on said carrier, and a link connecting said hand
lever with said rack, substantially as described and shewn in the drawings.
22. In a breech loading gun, the combination with a breech. block having
screw threads thereon, of a screw box having threads registering with those on
the breech block, a hinged carrier, a rack mounted on said carrier, a pinion held
against rotation on the breech block and engaging said rack, a link connected
to said rack and a hand lever connected to said link and operating said rack and
hinged carrier, with a safety device also operated by said hand lever for holding
said block against revolution in the screw box, when the breech is closed, sub-
stantially as described and shewn either in Figures 1, 6, and 31, or in Figure 35
of the drawings.
23. In a breech loading gun, the combination with a breech block having
screw threads thereon, of a screw box having threads registering with those of the
breech block, means for rotating said breech block, and for withdrawing same
from the screw box, firing mechanism, and a safety device engaging, said block
and holding same against revolution in the screw box when the breech is closed,

page_text: and also interrupting the action of the firing mechanism at all times except
when the breech is closed and locked, substantially as described and shewn in
the drawings.
24. In a breech loading gun, the combination with a sliding locking bar for
locking the breech block against turning in the screw box; of a lever a spring
catch carried by said lever, and engaging said locking bar, and a cam disengaging
said catch from said bar after said lever has travelled a short distance, substantially
as described and shewn in Figures 1, 0, and 18 to 31 of the drawings.
25. In a breech loading gun, the combination with a sliding safety device for
locking the breech block against turning in the screw box, and for preventing
premature discharge, of a hand lever for operating the breech mechanism and
cocking the firing mechanism, a spring catch carried by said hand lever and en-
gaging said safety device, and a cam located in the line of travel of said catch
and disengaging the same from engagement with the safety device after the hand
lever has been moved a short distance, substantially as described and shewn in
the drawings.
24
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