Improvements in Breech-loading Cannon.
Year: 1892

page_text: Date of Application, 26th July, 1892-Accepted, 24th Sept., 1892
COMPLETE SPECIFICATION.
Improvements in Breech-loading Cannon.
I SAMUEL SEABURY, Lieutenant United States Navy, residing at Schuyler
Place, Bergen Point in the County of Hudson and State of New Jersey, United
States of America, 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 particularly to breech-loading cannon in which, according
to my British Letters Patent No. 5697, dated April 15, 1890, a screw breech-
block, movable directly back and forth into the breech of the gun, is employed, in
combination with a swinging carrier, which is hinged to the breech of the gun, and
into which the said block is received, when withdrawn from the breech, and with a
swinging retractor, which is hinged to the breech to move independently of the
said carrier, for the purpose of withdrawing the said block from the breech into
the said carrier, and pushing it therefrom into the breech.
In the gun represented in that Patent for illustrating the invention therein
claimed, the necessary turning of the breech block, preparatory to its withdrawal
from the gun, and the swinging movement of the retractor, to effect the with-
drawal, are produced by separately operated devices, but a gun embodying the
present invention is distinguished from that by the retractor being made not only
to withdraw the block, but to produce the necessary preparatory turning thereof,
and is thereby considerably simplified. The present invention, however, not only
includes the breech-block operating mechanism, but improvements in the firing
mechanism, and in the mechanism for operating a cartridge shell extractor.
Fig. 1 is a rear view of a cannon embodying my invention, showing the breech
closed.
Fig. 2 is a side view of the breech portion of the gun corresponding with
Fig. 1.
Fig. 3 represents a horizontal central section of the same, corresponding with
Figs. 1 and 2.
Fig. 4 is a plan view of the retractor detached from the gun.
Fig. 5 is a rear view of the lower bracket of the hinge of the breech block
carrier.
Fig. 6 is a rear view, and Fig. 7 a vertical section, of portions of the firing
mechanism.
Fig. 7 is a side view of the firing pin detached.
Fig. 8 represents a central vertical section corresponding with Figs. 2 and 3.
Fig. 8A represents a vertical section of part of the breech, the carrier, and part
of the breech block within the carrier.
Fig. 8B is a side view, and Fig. 8° a face view, of the connecting piece by which
the retractor is connected with the breech block.
Fig. 9 is a horizontal sectional view of the breech portion of the gun, with the
breech open.
Fig. 9 represents part of the cartridge shell ejector.
Fig. 10 is a rear view of the breech block carrier detached from the gun.
Fig. 11 is a plan view of the breech block carrier.
Fig. 12 is a back view of the locking device for locking the breech block carrier
to the breech of the gun.
Similar letters of reference designate corresponding parts in all the figures.
A is the breech, counterbored, screw-threaded, and longitudinally grooved, to
receive a mutilated screw threaded breech block B, the counterbore and the block
being represented as having four longitudinal grooves. The number of grooves is,

page_text: however, not very material, but I prefer that number, as the breech block is thereby
unscrewed by one eighth of a turn.
CC are two hinge brackets affixed to the breech to receive the hinge pin E,
by which the swinging breech block carrier D D D is attached to the breech.
The hinge is represented on the right side of the breech. The lower bracket C is
made with a flange a, which lies against the face of the breech of the gun, and
with a flange a', which lies against the side of the breech, the said flanges receiving
screws which affix the bracket to the breech. The upper bracket C has
flanges b, which receive screws by which the said bracket is affixed to the face of the
breech. The hinge pin E also constitutes the fulcrum for a horizontal hand
lever F, which serves to actuate the whole of the breech mechanism. The said
pin E, in the example represented, is supposed to be forged with, or otherwise
affixed to the said lever. The carrier D D D is represented (see particularly
Figs. 10 and 11) as consisting of a tray D, with two arms D' D2 having eyes to
receive the hinge pin E, one of the said eyes being above, and the other below the
lower hinge bracket C, as shown in Figs. 1 and 2.
Gis the breech block retractor, consisting of a horizontal cam or cam-like plate
or bar having, as shown in Fig. 4, a deep socket at one end, a straight slot cat
the other end, and an intermediate curved slot c². This retractor is arranged, as
shown in Figs. 1 and 2, between the carrier D D D and the hand lever F. The
straight slot receives within it the hinge-pin E; the curved cam slot e² receives
within it a pin or upright stud f, which is secured to the land lever F, and the
socket receives within it a pin d, which connects it with the breech block,
the said pin passing also through the lugs e el on the back of a connecting piece H
(see Figs. 1, 8, 8, and 8), on the front of which is a screw threaded ping, which
screws into a hole provided for it in the lower part of the breech block, and
which forms a pivotal connection with the latter. This connecting piece His
represented as having, at its upper end. made in the same piece with it, a curved
slotted yoke p, but as this yoke constitutes no part of the breech-block operating
mechanism, but a part of the mechanism for cocking the firing pin, I will not
here further describe it. The pin d is held in place by a pin àª¹ (Figs. 1, 8³,
and 8c) screwing into H.
The retractor G, constructed, applied, and connected as above described, is
operated by the hand lever F in the following manner; first, to turn the breech-
block in the breech, next to withdraw the breech-block from the breech into
the carrier and afterwards to swing aside both the block and the carrier to open
the breech for loading.
When the breech-block is in its place in the breech of the gun and locked
therein, the hand-lever lies right across the face of the breech, as shown in Fig. 3.
The movements of the retractor, the breech-block, and the carrier, are effected by
taking hold of the handle F¹ provided on the lever, and moving the latter to the
position shown in Fig. 9. During the first part of this movement, the pin or
stud on the said lever, working in the cam slot 2 of the retractor, causes the
latter to move in a straight line across the breech to the right, the said movement
being permitted and guided by the hinge-pin, which, as before mentioned, is
received in the straight slot c. By the said straight movement, the connection of
the retractor with the breech-block, by the pin d and connecting-piece H, produces
the necessary turning movement of the block, and when this movement has been
accomplished, the pin fin the hand lever, still working in the cam slot c² in the
retractor, causes the latter to swing backward upon the hinge-pin E, and so draw
back the block into the tray of the carrier. The further continued movement
of the lever causes the retractor, the breech-block, and the carrier, the two
latter having been locked together by the locking latch provided for the purpose,-
to swing aside and open the breech, as shown in Fig. 9. By the return movement
of the lever, the retractor is caused to swing upon the hinge-pin E far enough,
first, to bring the breech-block and the carrier together up to the breech of the
gun, and then, the breech block having been unlocked from the carrier,-to

page_text: push the block forward into the gun, after which the completion of the movement
of the lever gives the retractor a movement to the left straight across the breech,
and causes it to turn and screw up the breech-block. All the movements of the
retractor by which the breech-block and the carrier are operated, are produced by
the movement of the pin of the lever in the cam slot of the retractor, the
movements being permitted and directed by the movement of the straight-slotted
part of the retractor on the hinge-pin E. When the breech-block is screwed up, any
tendency to unscrew it by the shock of the discharge of the gun, is resisted by the
shock being transmitted through the connecting-piece H and its pin d, to the
retractor G, and by the latter, through the pin and the lever F, to the pin E,
and the three pins d, f, E, being nearly in line, as shown in Fig. 3, the retractor
and the lever thus combine to form a substantially rectilinear brace in a direction
to resist the said tendency to unscrew.
It has been hereinabove mentioned, that the connection of the connecting-piece H
with the breech-block, by the screw-threaded pin g of the said piece, is in the
lower part of the breech-block. This connection should be such, that when the
block is turned half way in either direction, the said pin g should be directly under
the centre of the block. In that case, the vertical movement of the said connecting-
piece, relatively to the retractor G, which is unavoidable, is only equal to the
versed sine of the arc described by the said pin, which is comparatively small.
To compensate, however, for this, the space between the lugs e e¹ is made
sufficiently greater than the depth of the socket c of the retractor G, as may
be understood by reference to Figs. 1 and 8. In order to keep the pin d and the
connecting-piece H upright, and in proper relation to the retractor, during the
turning movement of the block, the piny of the connecting-piece must not be
screwed up tightly into the breech-block, but must be so fitted as to permit it to
have a slight turning movement in the block. lu orler that the longitudinal
movement of the ping may be very slight, its screw-threads should be very fine.
The tray D of the carrier is substantially like that employed in many other
breech-loading cannon of the same type, that is to say, it has guides (see
Figs. 10, 11) to be received in guide notches in the breech-block (see Fig. 1),
for the purpose of guiding the latter in its withdrawal, but instead of providing for
the stoppage of the block in the tray by shoulders at the front of the said guides hh,
I provide, all across the back of the tray, a stop-plate j. against which the rear
end of the block is stopped. This plate is omitted in Fig. 10, but is shown in all
the other figs. where the carrier is represented The said plate is dovetailed into
the back of the carrier, as shown at in Fig. 11, and secured by screws screwing
into the tray. Instead of locking the tray to the breech during the forward move-
ment of the breech-block by the retractor, and of locking the tray to the breech by
means of a tray-latch consisting of a hooked lever arranged lengthwise of the tray,
as is common, I employ, for the above purposes, a latch consisting of two
catches (see Figs. 1, 8, 8, 11, and 12), secured on opposite ends of a pin k
arranged lengthwise of the tray D, in a bearing k* (see Fig. 10), provided for it in
the carrier below the tray, so that the said catches work transversely to the tray.
The front catch is for engaging with the hooked pin, shown in Fig. 84, and
dotted in Figs. 1 and 9, commonly provided on the lower part of the face of the
breech for locking the tray to the breech. The rear catch for locking the carrier
to the block during the return movement of the block by the retractor, is in the
form of a trigger, as may be seen in Figs. 1 and 12, and always receives an upward
pressure from the end of a leaf spring m, which is secured to the carrier as shown
Fig. 11, the said upward pressure serving to engage the said catch with a
otch n (see Fig. 8) in the breech-block, when the latter is drawn to the back of
he tray, as shown in Fig. 84, and serving also to engage the catch &' with the
ooked pin on the breech, and thereby locking the tray to the breech when
t is brought close up thereto. The end of said catch k is beveled in front, as
hown in Figs. 8, 84, and 11, so that as the breech-block is being drawn back into
he tray, the said catch may be pressed down by the beveled face of a notch n (see

page_text: Figs. 1 and 8), provided on the rear face of the block opposite the notch n' above
described, and the catch is at the same time unlocked from the hooked pin lin
the breech, to permit the carrier to be swung aside with the breech-block, as the
latter is swung aside by the continued movement of the retractor G. By this
construction and arrangement of the breech locking latch, the catch 2 is made to
present a square shoulder or face to prevent the forward movement of the block
in the tray during the return movement of the block and the carrier, until the tray
arrives nearly close to the breech, when the catch is withdrawn from the notch n
by the catch A coming against the latch-like beveled outer face of the hooked pin
in the breech. The trigger-like downward extension of the catch (see Figs. 1
and 12) enables the carrier tray to be unlocked from the gun, or the breech-block
to be unlocked from the tray, by hand, whenever desired.
I is the firing-pin, shown detached in Fig. 7*, and also shown in Figs. 1, 3, and 8,
passing centrally through the breech-block. It is represented as of round
transverse section. J (Figs. 1, 3, 6, 7) is the sear, consisting of a straight plate
having a longitudinal dovetail guide tongue s on its back, working in a radial guide
groove in the rear face of the breech-block, and having in it an openings (see
Figs. 3 & 6) through which the firing-pin passes. The firing-pin has, at a short
distance from its pointed front end, a collar o, behind which the main spring gis
arranged within the central hole provided in the breech-block for the passage of
the pin. The rear end of the said central hole is closed by the insertion of a nut r
the front of which serves as an abutment for the main spring 7. Between one side
of this nut and the shoulder formed by the inner end of the dovetail tongue s, the
sear spring is arranged within the groove in the breech-block. For convenience
of construction, the dovetail guide tongues, and the sear itself, are made of two
pieces, and secured together by a screws. The firing-pin I has in it two grooves
or annular notches t, of which the forward one, t, which may be called the
cocking notch, is square-shouldered, and the rearward one,, which may be called
the sear-setting notch, has its front shoulder beveled. When the firing pin is
drawn back, it is cocked by the inner end of the openings of the sear engaging in
the cocking notch (, as shown in Fig. 6. When the firing-pin is thrown forward,
the sear-setting notch, having the beveled front shoulder, is within the opening s
of the scar.
The inner end of the said openings is beveled on the inner side, as
shown in Fig. 3, to correspond with the bevel of the front shoulder of the setting
notch'. As the pin is drawn back from the last mentioned position, to cock it,
the beveled front shoulder of the setting notch coming into contact with the
bevel on the inner end of the opening of the sear, causes the pin to move the latter
lengthwise far enough for the setting notch t' to escape from the openings, and
permit the backward movement of the pin, until its cocking notch arrives at the
sear, when the latter is forced by its spring s² into its cocking position in said
notch t.
T is the trigger, consisting of a small elbow-lever, pivoted by a pin w to a
slide T, which is fitted to work in a radial dovetail groove made in the face of the
breech, in such a position, that when the breech-block is screwed up, the sear and
the said slide are in exact alignment with each other, as shown in Fig. 1. The
trigger slide T has its outer end turned inward, as shown in Fig. 3, and entering
a recess w provided in the breech; and between the turned-in end of the said slide
and the inner end of the said recess w', the spiral trigger spring w² is placed in
said recess, where it tends to force the slide T¹ outwards as far as permitted by
the trigger, the turned-in point of which enters a recess w³ in the breech. By
pulling the outer end of the trigger, its turned-in point is pressed against the outer
end of the said recess w³, and the trigger slide T is thereby forced inward. When
the sear is opposite the trigger slide, it is capable of being pushed in by the said
slide, and of so liberating the firing-pin. Not only is the trigger shde T wholly
contained within the radial groove provided for it within the breech face, but the
trigger T itself, and the trigger pin te, are also, for the most part, contained in said
groove, and the said pin w is held in place by its ends being confined within said

page_text: groove. To provide for inserting the trigger pin into its place, a vertical groove w
(see Fig. 1), just large enough for the passage of said pin, is provided in the breech
face above the radial groove. To per nit the insertion of this pin, the trigger slide
and trigger when the breech-block is withdrawn, are pushed forward in the radial
groove far enough to bring the holes provided in them for the said pin opposite to
the vertical groove wt, and when the pin is inserted, the trigger spring will force
out the trigger and slide to their normal position, in which the pin w is confined
in the radial groove, the trigger slide not being moved so far inward, in firing, as
to carry the said pin to the vertical groove c*.
む
In the lower edge of the sear is a notch (see Figs. 6 and 7), for the reception
of the end of a locking-piece », which serves the purpose of locking the scar, and
so causing the latter to lock the hammer in the cocked position while the breech
is open, or the breech-block is in any other position than tightly screwed up. This
locking-piece consists of a small sliding bolt fitted to a dovetail guide-recess in the
breech-block, and pressed upward or toward the sear by a small spiral spring
(Fig. 7), which is arranged on a small pin e, which stands up from the bottom of
the said dovetail recess, the bearing for the said spring being a shoulder on the
said pin. The said locking piece has, on its outer face, a pin or projection &³,
through which it is operated upon as hereinafter described, by means of the yoke p
on the top of the retractor-connecting-piece H, for the purpose of automatically
unlocking the scar, as shown in Figs. 6 and 7, when the breech-block is
screwed up.
The
of
The cocking of the firing-pin might be effected by pulling back the said pin by
a lanyard attached to an eye in the back of its head, but in order to provide for
its being cocked automatically by the act of screwing up the breech-block, I pro-
vide the curved-slotted yoke p, hereinbefore referred to, on the connecting-piece H,
by which the connection is made between the breech-block and the retractor.
firing-pin passes through the curved-slot of this yoke, the back of which is so
oblique to the block, as shown in Figs. 3 and 9, that the said yoke constitutes a
wedge or cam to operate against the correspondingly shaped front of the head
the firing-pin, for the purpose of drawing back and cocking the said pin by the act
of turning the breech-block to unscrew it. When the cocking has thus taken place,
the locking-piece before described is pressed by its spring into the notch v in
the sear, and the firing pin is locked in the cocked position, in which condition it
remains during the withdrawal and swinging aside of the breech-block for loading,
and during the return movement of the block into the gun after loading, and until
the screwing up of the block, but just before the screwing up is completed the pro-
jection on the locking piece is brought under the yoke p, as shown in Fig. 1,
and, by the completion of the screwing up, the locking piece, being held back,
allows the scar to unlock itself. The scar. however, remains unmoved, and keeps
the firing-pin cocked until the trigger T is pulled, when the gun is to be fired, but
the pulling of the trigger cannot liberate the firing-pin until the scar has been
unlocked by the completion of the screwing up of the breech-block, and hence all
danger of premature discharge is obviated.
As, during the above described act of cocking produced by the screwing up of
the breech-block, the firing-pin turns within the breech-block, or the breech-block
turns on the firing-pin, if, in firing, the said pin were allowed to move directly
forward without control, the beveled front of the head of the said pin might not
be left in proper position for re-engagement with the wedge or cam face of the
yoke p therefore, to provide for the proper control of the said pin, I provide on
one side of the collar o of the said pin, a small projecting pin o' (see Figs. 3 and 8),
and provide in the central bore of the breech-block through which the firing-pin
works, a groove o², as shown in Fig. 3, and dotted in Fig. 8, for the said pin to
work in the said groove having such a spiral direction as shown in the dotted
outline in Fig. 8, keeps the beveled front of the head properly directed towards the
wedge or cam face of the yoke.
The cannon herein represented has its brecch-block constructed without any

page_text: gas-check, as it is intended for the use of fixed ammunition, but a gun for firing loose
ammunition may be constructed in all other respects like that represented and
described, except that the breech-block would be provided with a gas-check, which
might be of any known or suitable kind, and it would not need a cartridge shell
ejector.
L(Figs. 8 and 9) is the cartridge-shell-ejector, consisting of a slide which works
back and forth in a guide-way cut into the lower part of the counterbore of the
gun which receives the breech-block. This ejector is provided, as in my herein-
before mentioned British Patent, with a flange n, which engages with a flange ul
on the front of the breech-block, for the purpose of starting the empty cartridge-
shell from the slight backward movement given to the block by unscrewing it.
The flange on the breech-block only extends so far that it will escape from the
Hange on the ejector when the breech-block is unscrewed, and so leave the ejector
in the gun until after the breech has been completely opened by swinging aside of
the retractor, breech-block, and carrier, as shown in Fig. 9. The rear end of the
retractor has in it a slot ², to receive a pin a, which stands up from the army of
a lever y (see Figs. 9 and 9*), the fulcrum y2 of which is arranged to turn freely
in a lug y³ (see Fig. 5), provided on the lower hinge-bracket C, the said lever
arms being fastened securely to the said fulcrum pin y. The longer army is
arranged above the said lug of the hinge-bracket, and the shorter arm y',
which is a mere toe, the form of which is shown in dotted outline in Fig. 9, is
below the said lug, and so situated that just before the outward movement of the
carrier and the breech-block is completed, it will be struck by a toe-like pro-
jection (see Figs. 1, 9, and 11), and that by the completion of the said outward
movement, the said toe-like projection, acting on the toc y', will produce the
backward movement of the ejector by which the cartridge-shell will be completely
withdrawn. The ejector is returned into the breech of the gun by the carrier
pushing against its rear end during the act of returning the breech-block.
=
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is
1. In a breech-loading cannon in which the breech-block has both a turning
movement on its axis and a backward and forward movement, the combination with
such a breech-block, of a pivot attached to the breech of the cannon, and a breech-
block-retractor connected with the said block and having a slotted connection with
the said pivot, whereby it is capable not only of a turning movement on said pivot
for retracting the said block from the gun and inserting it therein, but also of a
movement across the face of the breech, for the purpose of turning the said block
on its axis, substantially as herein set forth.
2. In a
breech-loading cannon in which the breech-block has both a turning
movement about its axis, and a backward and forward movement, the combination
with such breech-block of a pivot attached to the breech of the cannon, a breech-
block-retractor having at one end a slotted connection with such pivot, and a
connecting-piece having a pivotal connection with the other end of said retractor,
and a separate pivotal connection with the breech-block, substantially as and for
the purpose herein set forth.
3. In a breech-loading cannon in which the breech-block has both a movement
about its axis and a direct backward and forward movement, the combination with
such breech-block, of a fulcrum pin attached to the breech of the gun, a lever
working on said fulcrum pin and carrying a second pin, and a retractor consisting
of a cam-plate connected pivotally with the breech-block, and engaging with said
fulcrum pin and said second pin, for the two purposes of producing the movement
about the axis and the direct forward and backward movements of the breech-
block, by the movement of the said lever, substantially as herein set forth.
4. In a breech-loading cannon in which the breech-block is withdrawn in a
rearward direction, the combination with the breech-block-carrier hinged to the

page_text: breech of the cannon, a hand lever attached to the breech, to move independently
of the carrier, and carrying a pin or stud, and a swinging retractor connected with
the breech-block, and having a pivotal connection with the breech, on which
pivotal connection it works independently of the hand lever and carrier, and
having a direct engagement with said pin or stud on the hand lever, substantially
as herein set forth.
5. In a breech-loading cannon in which the bre :ch-block has both a movement
about its axis and a backward and forward movement, the combination of a breech-
block-carrier hinged to the breech of the cannon, a lever and a fulcrum pin for the
same attached to the breech, and a retractor consisting of a cain plate connected to
the breech-block, and engaging with said lever, for the purposes of retracting it
from the breech into the carrier and of pushing it from the carrier into the breech,
substantially as herein set forth.
6. In a breech-loading cannon in which the breech-block has a turning move-
ment about its axis and a direct backward and forward movement, the combination
of a fulcrum pin attached to the breech of the cannon, a lever working on said
fulcrum pin and carrying a second pin, a breech-block-retractor consisting of a
cam plate having two slots, by one of which it engages with said second pin, and
by the other with said fulcrum pin, and a connecting-piece having a pivotal con-
nection with the breech-block and a separate pivotal connection with the breech-
block-retractor, substantially as herein set forth.
7. The combination with the breech of the cannon, the breech-block capable of
moving backwards and forwards therein, the swinging breech-block-carrier and the
locking hook on the breech, of the locking latch consisting of a pivot k,
arranged lengthwise of the tray of the carrier, and having at its ends, catches k¹ k²,
to engage respectively with the said locking hook 7, and the notch n in the
breech-block, by a movement transverse to the tray, substantially as herein set
forth.
8. The tray D of the breech-block-carrier constructed with a stop-plate across
its rear, substantially as herein described.
9. The combination with the gun and the breech-block fitted to turn on its axis
therein, and the firing pin passing through the block, of a connecting-piece_attached
to said block for turning it, and provided with a cam for engaging with and cocking
the firing pin, substantially as herein set forth.
10. In a breech-loading cannon in which the breech-block has a turning move-
ment on its axis, and in which there is a firing-pin passing through said breech-
block, the combination of a cam plate or bar, and means of moving the same across
the breech for turning the latter, of a connecting-piece between the said plate or
bar and the breech-block and the firing-pin, the said connecting-piece having a
pivotal connection with the breech-block, and a separate pivotal connection with
the said cam plate or bar, and having on it a cam for engaging with the firing pin,
for the purpose of cocking the said pin, substantially as herein set forth.
11. The piece for turning the breech-block and cocking the firing-pin consisting
of a plate El, having a screw-threaded pin g, and having lugs e e¹ for a pivotal
connection with turning mechanism, and having a slotted yoke p for engagement
with the firing pin, substantially as herein set forth.
12. The combination with the breech-block and the firing-pin passing through
the same, of the projection o' on the firing-pin, and the spiral guide o² provided in
the breech-block to receive said projection, for the purpose of preventing the
iring pin from turning with the breech-block, substantially as herein described.
13. The combination with the screw breech-block, the scar fitted radially to
aid block, and the connecting-piece attached to the breech-block, for turning the
atter, of the locking piece fitted to the breech-block, to engage with the sear
for locking the same, and to be disengaged by said connecting-piece, in the act of
crewing up the breech, substantially as herein set forth.
14. The combination with the breech face provided with a radial groove, and
with a groove to communicating with said radial groove, of the trigger T, trigger

page_text: slide T, and their connecting pin w, all arranged within said radial groove, with
the said pin held in place by said groove, substantially as herein described.
Dated this 26th day of July 1892.
NEWTON & SON,
Agents for the Applicant.