Improvements in and connected with Breech Mechanism for Quick-firing Guns.
Year: 1891

page_text: Date of Application, 30th Apr., 1891
Complete Specification Left, 30th Jan., 1892--Accepted, 2nd Apr., 1892
PROVISIONAL SPECIFICATION.
Improvements in and connected with Breech Mechanism for
Quick-firing Guns.
I, JOHN EBENEZER BOUSFIELD, of the firm of G. F. Redfern & Co., The
General Patent Office, No. 4, South Street, Finsbury, in the County of Middlesex,
Patent Agents, do hereby declare the nature of this invention (a communication
to me by Oskar William Bergman, of Gothenburg, in the Kingdom of Sweden,
Lieutenant in the Royal Swedish Artillery) to be as follows:-
This invention relates to new or improved breech-mechanism for quick-firing
guns.
In carrying out the said invention I provide a cylindrical block the periphery
of which is divided in four segments, of which two are threaded and two have the
threads cut away; a ring hinged to the breech of the gun and through which
passes the rear end of the block, a hand lever which is fixed at the rear end of the
breech-block and by which the different movements of the same are effected; a
cartridge extractor and a bar which acts upon the same, and a firing arrangement
placed in the block.
In order to open the breech the hand lever has to be turned 90°, whereby the
breech-block (the threads of which engage in corresponding threads in the breech
of the gun) will be turned so that its threaded segments come opposite unthreaded
parts in the breech of the gun. These parts are so placed with regard to the
pivot pin of the hinge of the ring that the said ring and block can be turned to
the side of the gun, after the threads have been disengaged. For closing the
breech the action is reversed, that is to say, the ring and the block are turned
round their hinge and then the block is locked by being turned 90° by the hand
lever.
There is only a slight longitudinal movement between the block and the ring
due to the pitch of the thread.
During the time that the threads of the blocks are disengaged from the threads
in the breech of the gun, they are engaged in corresponding threads in the ring
and when the block and ring are turned upon the hinge pin, a part of the extractor
bar enters a groove in the block. By these arrangements the block is firmly
held in the ring and caused to partake of its movements.
I prefer to effect the extraction of the empty cartridge cases by the use of a
lever placed in an opening in the side of the breech and kept in place by the
extractor bar which as stated before slides in a groove in the breech. The
extractor lever with one end engages behind the rim of the cartridge case while
the other engages with one end of the said extractor bar.
When the ring is turned upon its hinge, an eccentric surface first slightly moves
the extractor bar, and then the ring gives to the bar a blow, whereby the cartridge
case is first loosened and finally ejected.
My block can be provided with any known mechanical or electrical firing
arrangement, but in practice I advantageously provide a firing pin having a lug
which moves longitudinally in a groove in the ring, and passes through the breech-
block. An inclined surface in the hole in the breech-block through which the said
lug passes, draws back the firing pin, and cocks the firing spring when the block is
turned. At the end of this turning motion, the firing pin engages with a sleeve
and turns the same sufficiently to retain the firing pin in its cocked position. In
order to fire the gun when the breech is closed it is only necessary to turn back the
sleeve, which I generally do by pulling a trigger in a direction opposite to that in
which the firing pin is working. The trigger has a lug similar to that of the firing

page_text: pin and engages in the same groove in the ring when the trigger is drawn back.
An inclined surface upon the lug acts upon the sleeve for turning the same and
liberating the firing pin.
The lug of the trigger passes through the same hole in the breech-block as the
lug of the firing pin. The rear surface of this hole prevents the trigger from being
pulled before the breech is closed.
Dated the 30th day of April 1891
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in and connected with Breech Mechanism for
Quick-firing Guns.
I, JOHN EBENEZER BOUSFIELD, of the firm of G. F. Redfern & Co., The
General Patent Office, No. 4, South Street, Finsbury, in the County of Middlesex,
Patent Agents, do hereby declare the nature of this invention (a communication
to me by Oskar William Bergman, of Gothenburg, in the Kingdom of Sweden,
Lieutenant in the Royal Swedish Artillery) and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement :-
This invention relates to new or improved breech-mechanism for quick firing
guns, and is illustrated in the accompanying drawings, in which :-
Figure 1 is a side elevation of the rear end of a quick firing gun, provided with
breech-mechanism constructed according to this invention, the parts being in the
position they occupy when the breech is closed and the gun has just been fired:
Figure 2 is a vertical section:
Figure 3 a horizontal section; and,
Figure 4 an end elevation of the same:
Figure 5 is a horizontal section shewing the breech opened:
Figures 6 and 7 are cross sections on the lines A B and C D respectively of
Figure 2;
Figures 8 and 9 are developed views of holes in the breech-block and sleeve
hereinafter described and
Figure 10 is a cross section of the breech block or screw.
Similar letters in all the figures indicate similar parts.
In carrying out the said invention I provide a cylindrical block or breech
screw a, the periphery of which is divided into four segments, of which two are
threaded and two have the threads cut away; a ring or shutter b, hinged to the
breech of the gun and in which is located the rear end of the block a; a hand-
lever c which is fixed at the rear end of the breech-block a and by which the
different movements of the same are effected; a cartridge extractor d and a bar e
which acts upon the same and slides in a groove made in the exterior of the breech
of the gun, the extent of movement of the said bar being limited by the pivot pin ƒ
of the ring or shutter b; and a firing arrangement placed in the breech-block a,
and consisting of a firing-pin g, a sleeve h, a trigger i and two springs and k.
In order to open the breech, the hand-lever chas to be turned 90° whereby the
breech-block (the threads of which engage in corresponding segmental threads in
the breech of the gun) is turned so that its threaded segments come opposite the
unthreaded parts in the breech of the gun. These parts are so placed with regard
to the pivot-pin f of the hinge of the ring or shutter 6 that. the said ring and the
block a can be turned to the side of the gun, as shewn in Figure 5, after the threads
have been disengaged. For closing the breech the action is reversed, that is to say,
the ring or shutter b and the block a are turned round their hinge f, and then the
block is locked by being turned 90° by the hand-lever c.

page_text: During the time that the threads of the block a are disengaged from the threads
in the breech of the gun, they are engaged in corresponding segmental threads in
the ring or shutter b.
There is only a slight longitudinal movement between the breech-block a and the
ring or shutter 6 due to the pitch of the thread.
с
The hand-lever c is keyed on the rear end of the breech-block a by means of a
tenon or key formed thereon and a spring-fork m which thus firmly holds the
block a, the ring or shutter b, and the hand-lever c together. When the rear part
of the screw of the breech-block a is engaged in the corresponding threads made in
the ring or shutter b the block during the whole of the opening of the breech will
obviously be always firmly held in the ring or shutter b and caused to partake of its
movements.
As already stated the whole breech closing arrangement can pivot around the
hinge as soon as the threads of the breech-block a shall be disengaged from those
of the gun; to prevent the block from rotating in the ring or shutter b during its
movement upon the hinge fa part a', Figure 5, of its threads is cut away or
flattened and the rear part of the extractor-bar e engages in the groove thus
formed on the block a during the whole of the movement upon the hinge f.
I effect the extraction of the empty cartridge cases by the use of the lever or
extractor d placed in an opening in the side of the breech and kept in place by
the extractor-bar e which, as before stated, slides in a groove in the breech. The
extractor lever d with one end n engages behind the rim of the cartridge case while
the other end o is acted upon by the part a¹ of the said extractor-bar.
When the ring or shutter b is turned upon its hinge f, a curved surface
p on the
ring or shutter b and eccentric to the hinge f, first slightly moves the extractor-
bar e forward and then the part g of the ring or shutter 6 gives the bar a blow
which it communicates to the extractor lever d, whereby the cartridge case is first
loosened and finally ejected. To allow of the longitudinal movement of the
extractor-bar in the groove in the breech of the gun the hole in the extractor-bar
through which the pivot passes is made larger than the pivot in one direction as
shewn in Figures 3 and 5. The extractor lever is held in place in the gun by two
pivots thereon engaging in two recesses made in the breech for this purpose, and
by the extractor-bar e.
My block can be provided with any known mechanical or electrical firing
arrangement but in practice I advantageously provide the firing-pin g having a
lugs which passes through the breech-block a into a groove t in the ring or
shutter b in which it moves longitudinally. An inclined surface u, Figure 8, in the
hole in the breech-block through which the said lug passes, draws back and cocks
the firing pin g when the block is turned. At the end of this turning motion, the
tenon or key on the handle c engages with the sleeve and turns the same
sufficiently to retain the firing-pin g in its cocked position as hereinafter described.
In order to fire the gun when the breech is closed it is only necessary to turn back
the sleeve h, which I do by pulling the trigger i in a direction opposite to that in
which the firing-pin g is working. The trigger has a lug v similar to that of the
firing-pin g and engages in the same groovet in the ring or shutter b when the
trigger is drawn back. An inclined surface upon the lug acts upon the sleeve for
turning the same and liberating the firing-pin.
The lug of the trigger i passes through the same hole in the breech-block a as
the lugs of the firing-pin g. The rear surface of this hole prevents the trigger
from being pulled before the breech is closed.
Supposing the gun to have been fired and the breech to be then opened by means
of the hand-lever c, the inclined surface u, Figure 8, in the breech-block commences
to move back the firing-pin g. It is therefore clear that a circular displacement of
the inclined surface u will cause the firing-pin to move back as far as the shoulder
against which it then bears.
The lugs will occupy the dotted position s', Figure 8, when the hand-lever c has
been turned 90 degrees. Towards the end of this movement of 90 degrees the

page_text: sleeve h, actuated by the tenon or key formed on the hand-lever c will rotate to a
sufficient extent to cause a shoulder y (Figures 2 and 9) with which it is provided
to be placed in front of the lugs of the firing-pin g to retain the latter in firing
position while the breech is being closed. The firing-pin is constantly pressed
forward by the spring j, one end of which bears upon the sleeve and the other
upon the head z of the firing-pin. It is therefore clear that, as soon as the sleeve h
is completely turned back by pulling the trigger the firing-pin will be liberated and
will be projected forward under the action of the spring j
Figures 2 and 3 shew the position of the firing mechanism after the gun has
been fired, while Figure 5, in which the breech-mechanism is open, shews the
firing-pin drawn back and the mechanism in position for firing.
k
The gun having been fired by means of the trigger i the spring & immediately
the trigger is released will move it forward again when its lug v comes in contact
with a shoulder 6', Figure 9, in the sleeve / but as the latter will be moved towards
the end of the movement of 90° by the tenon of the handle e as above described
the lug will move from the position into the position through the action
of the spring (the latter position being occupied during the end of the movement
of 90 degrees, see Figures 5 and 9, and during the opening of the breech), the
trigger i will then occupy its extreme forward position and cannot be actuated by
the person working the gun until the breech is absolutely closed, as the surface c'
of the breech-block a will prevent the lug v from recoiling in the groove t so long
as the breech-block has not been completely turned 90 degrees for effecting the
closing. From what has been stated it will be understood that the firing-pin is in
firing position and the trigger ready to be actuated for firing the gun only when the
breech-mechanism is completely closed.
The disengagement of the firing-pin g is effected as follows:-
The 90° being completed the trigger i can be drawn back when its lug v slides
in the groove t from the position to that of v', and at the same time turns the
sleeve by acting upon its inclined plane d', whereby the shoulder y which opposes
the forward movement of the firing-pin will be sufficiently turned away to allow the
spring to force forward the firing-pin g and fire the cartridge. The disengage-
ment may, however, be caused by means of a trigger movement placed on the side
of the gun and operated by the finger, or by a suitable electrical arrangement.
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 I
claim is :-
1. In a breech-mechanism for quick-firing guns, a cylindrical block or breech
screw, the periphery of which is divided into four segments, of which two are
threaded, and two have the threads cut away, the segmental threads corresponding
to similar segmental screw-threads in the breech, the said block being connected to
a hinged ring or shutter to allow of the block leaving the breech after it has been
turned a quarter of a revolution by means of a hand-lever, substantially as herein-
before described and illustrated in the accompanying drawings.
2. In a breech-mechanism for quick-firing guns, a cylindrical block or breech
screw provided with interrupted threads which are adapted to engage in corre-
sponding interrupted threads in a ring or shutter arranged to pivot upon a hinge,
so as to firmly connect the breech-block or screw to the said ring or shutter during
the opening of the breech, substantially as hereinbefore described and illustrated in
the accompanying drawings.
3. In a breech mechanism for quick-firing guns, the herein described arrangement
of groove formed in the breech screw by cutting away or flattening the threads
thereof, the rear part of the extractor bar engaging in the said groove during the
whole of the movement of the ring or shutter upon the hinge when the breech is
opened, thereby preventing the said screw from turning until the moment of
closing, substantially as set forth and illustrated in Figures 2 and 5 of the
accompanying drawings.

page_text: 4. In a breech mechanism for quick-firing guns, the arrangement for firing the
cartridges consisting of the firing-pin g, sleeve h, trigger i and springs j and k,
substantially as hereinbefore described and illustrated in the accompanying
drawings.
5. In a breech-mechanism for quick-firing guns, the sleeve which carries the
trigger-spring constructed and arranged in such a manner as to prevent the gun
from being fired before the breech is perfectly closed, substantially as hereinbefore
described and illustrated in the accompanying drawings.
6. In a breech-mechanism for quick-firing guns, the safety arrangement of the
trigger hereinbefore described and illustrated in the accompanying drawings.
7. The combination of parts forming the improved breech mechanism for quick-
firing guns arranged and operating substantially as hereinbefore described with
reference to the accompanying drawings.
Deted the 30th dev of Jenu189
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.