Improvements in and connected with Breech-loading Guns or Ordnance.
Year: 1890

page_text: Date of Application, 21st Aug., 1890
Complete Specification Left, 22nd June, 1891-Accepted, 25th July, 1891
PROVISIONAL SPECIFICATION.
Improvements in and connected with Breech-loading Guns or
Ordnance.
We, CHARLES GUSTAV MELLSTRÖM, and AXEL BREMBERG, both of
32, Victoria Street, in the City of Westminster, Civil Engineers, do hereby declare
the nature of this invention to be as follows:-
Our invention relates to breech-loading guns or ordnance of the kind in which a
screw breech-block is employed, which is locked and unlocked by a partial rotation
upon its axis.
Our said invention comprises improved means for effecting the opening and
closing of the breech and for extracting the empty cartridge cases, and improved
means for utilizing the force of the recoil for operating the breech-block.
According to our invention the breech-block, instead of being mounted directly
in the carrier-ring, is mounted in a ring secured within the carrier-ring, this inner
ring being provided with slots so that the breech-block can slide backwards and
forwards therein. The longitudinal movement of the breech-block through
the inner ring is effected by means of a rack in one of the longitudinal slots in the
breech-block and a toothed segment mounted upon the vertical shaft forming the
axis of movement of the carrier-ring. The teeth of the segment are formed on
the exterior of a hollow box having within it a bush or socket which is internally
screw-threaded to correspond with screw-threads formed upon the said vertical
shaft, so that rotary motion can be imparted to the said shaft without imparting
motion to the pinion. Within the box is placed a cam-cylinder connected with the
vertical shaft by keys or feathers, so that while rotary motion is being imparted to
With this
the cam-cylinder by the said vertical shaft, the latter can slide therein.
arrangement any motion imparted to the vertical shaft to cause the opening of the
breech-block, first of all causes the rotation of the cam-cylinder, a cam-groove in
which acts upon a pin secured to an arm projecting from the inner ring securing the
breech-block in such a manner as to cause the partial rotation of the said block to
unlock the same. During the unlocking of the block the vertical shaft rises under
the action of the screw-threads: by the time, however, that the breech-block has
been unlocked the screw has reached the limit of its upward movement so that
motion is then imparted to the box having the teeth of the segment thereon,
whereby the breech-block is drawn backwards out of the breech of the gun. When
the inner extremity of the rack comes into contact with the segment any further
backward movement of the block is prevented, so that the continued movement of
the vertical shaft causes the carrier-ring and consequently also the block within it
to be moved out of the line of the breech.
The teeth on the portion of the breech-block within the carrier-ring are
lengthened in such a manner that they are constantly in engagement with the
teeth of the segment, notwithstanding the partial rotation of the block on its
axis.
The box carrying the segment is provided with a suitable slot to allow
the pin upon the arm of the breech-block to enter the cam-groove in the
cam-cylinder.
In order that during the closing of the breech the various operations shall take
place in their proper order, we provide upon a ring in conjunction with the breech-
block an arm which, when the block is partially rotated to unlock the breech,
comes to bear beneath the end of the vertical shaft and supports the same in its
elevated position; and in order to prevent the carrier-ring from turning upon
its axis until the block is quite out of the breech and to prevent the inward move-

page_text: ment of the block until the carrier-ring is quite home, we provide a spring bolt in
the carrier-ring which, when the said ring is quite closed projects into a slot in the
wall of the breech chamber, and which is not withdrawn from the said slot until
the breech-block has been drawn completely back and a recess therein coincides
with the bolt and allows it to drop. In conjunction with the bolt is a catch which
is adapted when the breech is open to engage with a pin on the bolt, but which
when the carrier-ring is closed against the gun comes into contact therewith so that
it is moved out of engagement with the bolt, whereby the latter again locks into
the breech.
The extraction of the cartridges is effected by means of an extractor .or
extractors operated from a lever arranged eccentrically to the axis of the vertical
shaft, which lever is designed to be operated in such a manner that, during the first
part of the rotating movement of the whole mechanism, the extractor is operated
upon very forcibly to slowly move the case of the cartridge and then, as the rotary
movement of the mechanism continues, more rapidly by the impingement of a lug
or projection upon the box carrying the segment with a corresponding projection in
connection with the extractor-lever.
The movement of the vertical shaft for effecting the opening and closing of the
breech can be effected either by hand or by the force of the recoil, the motion being
imparted to the said vertical shaft by means of a bevel-wheel engaging with a
pinion upon the vertical shaft. When the motion is to be imparted by hand it is
effected through the medium of a crank handle in connection with the bevel-wheel.
When, however, the recoil is to be utilized for the purpose we provide the following
arrangement of mechanism, that is to say, the bevel-wheel is mounted upon a shaft
extended longitudinally of the gun, preferably adjacent to the hydraulic buffers
usually employed, which shaft slides in suitable guides formed upon the gun-carriage,
and is hereinafter referred to as the horizontal shaft.
Surrounding one part of this horizontal shaft is a spiral-spring secured at one end
to a bush in the bearing through which the rod slides so as to be incapable of
rotation, and at the other end to a collar upon the said shaft; upon the other
portion of the shaft is a sleeve having a cam-groove therein, and adapted to be
connected with and disconnected from the shaft by means of a pin engaging with a
collar on the shaft. In the said sleeve is formed a cam-groove into which a pin on
the gun-carriage projects in such a manner that while the gun is recoiling, carrying
with it the horizontal shaft, the sleeve will be rotated sufficiently to cause its spring
pin to engage with the collar on the horizontal shaft. Upon the return of the gun
under the action of the hydraulic buffers, the said sleeve will be rotated in the
reverse direction, and as the horizontal shaft is locked to the sleeve it will be
partially rotated also, whereby a certain amount of torsional power will be imparted
to the spring. When the spring-pin is drawn out of engagement with the collar
upon the shaft the torsion of the spring causes the shaft and also the bevel-wheel
mounted thereon to rotate a sufficient distance to impart the required amount of
movement to the vertical shaft of the breech mechanism. Any suitable means
may be employed for effecting the engagement and disengagement, of the sleeve
from the shaft.
To enable either the crank handle or the recoil mechanism to be used.at
will for operating the breech-block the bevel-wheel is provided with a sleeve.or
elongated boss upon the shaft, and the handle surrounds the said sleeve.
In order to provide for locking either the shaft of the recoil mechanism to the
boss of the bevel-wheel or the handle to the bevel-wheel we provide a key which,
by means of a screw, may be moved to cause it to engage with the handle and the
bevel-wheel, or with the shaft and bevel-wheel so that, when the handle is not
required, it remains stationary.

page_text: COMPLETE SPECIFICATION.
Improvements in and connected with Breech-loading Guns or
Ordnance.
We, CHARLES GUSTAV MELLSTRÖM & AXEL BREMBERG, both of
32, Victoria Street, in the City of Westminster, Civil Engineers, 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:
Our invention relates to breech-loading guns or ordnance of the kind in which a
screw breech-block, which is locked and unlocked by a partial rotation upon its
axis, is employed.
Our said invention comprises improved means for effecting the opening and closing
of the breech and for extracting the empty cartridge cases, and improved means for
utilizing the force of the recoil for operating the breech-block.
According to our invention the breech-block, instead of being mounted directly
in the carrier-ring, is mounted in an auxiliary ring located within the carrier-ring,
this inner ring being provided with grooves so that the breech-block can slide
backwards and forwards therein.
A rack is formed in one of the longitudinal grooves in the breech-block and a
toothed segment mounted upon the vertical shaft, forming the axis of movement of
the carrier-ring, engages therewith. The teeth of the segment are formed on the
exterior of a hollow box having within it a bush or socket which is internally
screw-threaded to correspond with screw-threads formed upon the said vertical
shaft, so that rotary motion can be imparted to the said shaft without imparting
motion to the said toothed segment. Within the box is placed a cam-cylinder
connected with the vertical shaft by keys or feathers.
The teeth on the portion of the breech-block within the carrier-ring are
broadened in such a manner that they are constantly in engagement with the
teeth of the segment, notwithstanding the partial rotation of the block on its
axis..
The box carrying the segment is provided with a suitable slot to allow a
pin connected to the auxiliary ring to enter the cam-groove in the cam-cylinder.
In order that during the closing of the breech the various operations shall take
place in their proper order, we provide in conjunction with the breech-block an
arm which, when the block is partially rotated to unlock the breech, comes to bear
beneath the end of the vertical shaft and supports the same in its elevated position;
and in order to prevent the carrier-ring from turning upon its axis until the block
is quite out of the breech and to prevent the inward movement of the block until
the carrier-ring is quite home, we provide a spring-bolt in the carrier-ring which,
when the said ring is quite closed projects into a slot in the wall of the breech
chamber, and which is not withdrawn from the said slot until the breech-block has
been drawn completely back and a recess therein coincides with the bolt and allows
it to drop. In conjunction with the bolt is a catch which is adapted, when the
breech is open, to engage with a pin on the bolt, but which, when the carrier-ring
is closed against the gun, comes into contact therewith so that it is moved out of
engagement with the bolt, whereby the latter again locks into the breech.
The extraction of the cartridges is effected by means of an extractor or
extractors operated from a lever arranged eccentrically to the axis of the vertical
shaft.
The movement of the vertical shaft for effecting the opening and closing of the
breech can be effected either by hand or by the force of the recoil, the motion
being imparted to the said vertical shaft by ineans of a bevel-wheel engaging with
a,pinion upon the vertical shaft. When the motion is to be imparted by hand it is
effected through the medium of a crank-handle in connection with the bevel-wheel.

page_text: When, however, the recoil is to be utilized for the purpose, we provide the
following arrangement of mechanism, that is to say, the bevel-wheel is mounted
upon a shaft extended longitudinally of the gun, preferably adjacent to the
hydraulic buffers usually employed, which shaft slides in suitable guides formed
upon the gun-carriage, and is hereinafter referred to as the horizontal shaft.
Surrounding one part of this horizontal shaft is a spiral-spring secured at one end
to a bush in the bearing through which the shaft slides, the said bush being formed
square or otherwise so as to be incapable of rotation, and at the other end to a
collar upon the said shaft; upon the other portion of the shaft is a sleeve having a
cam-groove therein, and adapted to be connected with and disconnected from the
shaft by means of a spring-pin engaging with a collar on the shaft.
To enable our invention to be fully understood we will describe the same with
reference to the accompanying drawings, in which:-
Figure 1 is a side elevation of the breech end of a gun having our improvements
applied thereto; and,
Figure 2 is a rear view of the same:
Figure 3 is a view similar to Figure 2 but having certain parts removed:
Figure 4 is a section on the line w w, Figure 3:
Figures 5 to 19 are views of details of our invention.
Similar letters of reference indicate corresponding parts in the several figures.
a indicates the gun, and 6 the cradle in which the gun is free to recoil.
c is the
carrier-ring which is hinged or pivotted to the gun upon the shaft c, and d is the
auxiliary ring located within the carrier-ring. e is the breech-block sliding within
the said auxiliary ring. f, are the rack-teeth formed in one of the slots of the
breech-block, and f1, f¹ are the teeth in engagement with the said rack, the said
teeth, as hereinbefore stated, being formed on the exterior of a hollow box f²,
shewn detached in elevation and plan in Figures 5 and 6 respectively. ³ indicates
the bush or socket having internal screw-threads, the said threads being adapted
to engage with corresponding threads upon the shaft c', which shaft is shewn
detached in Figure 7 and is formed with the lower part c² of larger diameter than
the upper part so as to form a shoulder c³.
g is the cam-cylinder which is adapted to fit within the box f2, the said cylinder
being shewn in elevation and plan in Figures 8 and 9 respectively. This cylinder g
is adapted to fit onto the smaller part of the shaft c¹ and is connected thereto by
a spline joint so as to rotate with the said shaft.
g is a cam groove formed in the cylinder and having projecting into it a
roller-stud carried by a projecting arm g³ upon the ring d. A slot is formed
through the box f to allow the stud 92 to work in the slot g', as shewn most
clearly in Figures 3 and 4.
The operation of the apparatus as thus far described is as follows:- that is to
say, when rotary motion is imparted to the shaft c' the cam-cylinder g is caused to
rotate, whereby the cam-slot therein will act upon the stud 2 and thus rotate
the ring d and with it the breech-block sufficiently to unlock the latter, that is to
say, to bring the screw-threaded portions of the breech-block into the unthreaded
portions of the breech and vice versa. During the unlocking of the block, the
vertical shaft c rises under the action of the screw-threads f, but, by the time that
the breech-block has been unlocked, the shoulder 3 upon the shaft c¹ comes into
contact with the underside of the bush 3, so that motion is then imparted to the
box, whereby, owing to the engagement of the teeth f¹ upon the said box with
the teeth on the breech-block, the said breech-block will be drawn back through
the ring d until a flange h upon the end of the said breech-block bears against the
said ring as the rotary motion of the shaft c¹ is continued the breech-block with
the carrier-ring is turned backwards out of the line of the breech. 0
In closing the breech, the first part of the rotary movement of the shaft c', in the
reverse direction to which it was previously turned, causes the carrier-ring to enter
its aperture in the breech and then the breech-block to be moved into the breech
and rotated to lock it.

page_text: i is the arm secured to the ring d and serving when the breech is unlocked to
support the shaft c¹ in its elevated position. The said arm during the unlocking of
the breech being moved from the position indicated in full lines in Figure 3 to that
indicated by the dotted lines.
"
j is the spring-bolt which projects through the carrier-ring c and the ring d: this
bolt, when the breech is closed, engages with a recess in the breech of the gun.
When, however, in opening the breech the flange has reached the ring d, a
recess, in the breech-block, comes opposite the said bolt j, whereby, under the
action of its spring, the end of the bolt adjacent to the said recess enters therein,
whilst the other end of the bolt it drawn out of the recess so that the carrier-ring
can be turned out of the recess in the breech. When, after the bolt has entered
the recess, the carrier-ring commences to open, a spring-catch k, which is normally
out of engagement with a pin k upon the said bolt, engages with the said pin by
means of a hole k and thus prevents the bolt from being drawn out of engagement
with the recess until the carrier-ring is again moved home into its recess in the
breech, whereby the spring-catch k, by impinging against the breech of the
gun, is
inoved out of engagement with the pin k then, as the breech-block is being moved
into the breech, the spring-bolt is pushed back into engagement with the recess j¹
owing to the inclined shape of the end of the spring-bolt and of the recess j².
I is the extractor which is shewn detached in plan, side view and end view in
Figures 10, 11 and 12 respectively; this extractor slides in a suitable groove in the
gun, as indicated by dotted lines in Figure 3, and is provided at its front end with a
flange designed to engage with the flange of the cartridge.
m is the extractor-lever shewn in plan in Figure 13, one end of which constitutes
a kind of strap m¹ adapted to encircle a projection m from the underside of the
hinge portion of the carrier-ring e, which projection is eccentric to the shaft c¹,
whilst the other end is provided with a slot m² designed to engage with a pin on
the rear end of the extractor. The said lever on one side m³ is slightly curved and
adapted, when the gun is in position for firing, to bear against the flat side m' of a
recess in which the lever is located, as shewn most clearly in Figure 4. When the
breech-block with the carrier-ring is turned backwards out of the line of the breech,
the eccentric projection m* is rotated and thus the curved side m³ of the lever m is
caused to roll upon the flat side m' of the recess and so forcibly and slowly commence
to release the cartridge out of the breech. As the movement continues the lug n,
Figures 3 and 4, upon the underside of the carrier-ring c, strikes against a lug n¹
formed upon the strap portion of the lever m and so imparts a rapid movement to
the said lever to eject the empty cartridge case.
o is the bevel-pinion secured to the shaft c', and o' is a bevel toothed segment
engaging with the pinion o and serving, when rotated, to impart movement to the
spindle c. o is the handle, by means of which the bevel-wheels can be rotated
when the gun is to be operated by hand.
P is the horizontal shaft which is employed when the recoil is utilized for opening
and closing the breech of the gun; which shaft, near one end, is supported in a
bearing secured to the ring p³ (shewn detached in Figure 14) which is attached
to the gun for the purpose of actuating the ram of the hydraulic buffer when the
gun recoils, whilst at the other end the said shaft is supported by and is free to slide
in a bearing p³ carried in an arm projecting from the cradle b, as shewn most clearly
in Figure 1, and in Figure 15 which is a section on the line, Figure 1. The said
bearing på is of a square or other shape which will prevent it from rotating in its
seating. is the spiral spring surrounding a portion of the shaft and secured
at one end to the bearing p³ and at the other end to a collar 'upon the shaft p.
r is the sleeve surrounding the shaft p and having therein a cam-groove with
which engages a roller-stud upon the cradle in a manner which will be readily
understood by reference to Figure 16, which is a section on the line y ", Figure 1.
s is a spring-pin adapted to engage with a hole in a collar s, upon the shaft p,
as clearly shewn in Figure 17 (which is a longitudinal section shewing a portion of

page_text: the shaft p and the sleeve r) and to be disengaged therefrom through the medium
of a levers mounted upon a pivot and adapted to be acted upon by a lanyard ..
In order that the lever shall be in constant engagement, with the spring-pin,.
notwithstanding the rotation of the said pin with the sleeve r, the pin is provided
with a head shaving an elongated slot so, as shewn most clearly in Figure 1.
The operation of this apparatus is as follows, that is to say,, while the gun, is.
recoiling, carrying with it the horizontal shaft p, the sleeve will be caused' to.
rotate (owing to the engagement of the stud 2 with the groove r¹) sufficiently to
cause the spring-pins to engage with the collar s upon the shaft p.
Úpon
the return of the gun, under the action of the hydraulic buffers, (indicated by the
letter) the said sleeve will be rotated in the reverse direction and, as the
horizontal shaft is locked to the said sleeve, it will be partially rotated also, whereby
the pinion o will be rotated to open the breech as hereinbefore described and a
certain amount of torsional power will be imparted to the spring q.
In order to close the breech it is only necessary to pull the lanyard when,
through the medium of the lever s², the pins will be drawn out of engagement with
the collar s', whereby the torsional power of the spring y is free to act to rotate
the segment o' and the pinion o. In order that the shaft shall always return to the
same position under the action of the spring we provide upon the collar s'a lug t
designed to impinge against a projection upon the bearing pl as will be readily
understood by reference to Figure 1, and to Figure 18 which is a section on the
line, Figure 1.
To enable either the crank-handle or the recoil mechanism to be used at will for
operating the breech-block, the bevel-segment o' is provided with an elongated
boss upon which the handle o² is capable of rotating, as shewn in Figure 19
(which is a scction through the said boss and the handle o²). In order to provide
for locking either the shaft to the boss u of the bevel-segment, or the handle o² to
the bevel-wheel we provide a key which, by means of a thumb-screw v¹, may be
moved to cause it to engage either with the shaft and the bevel-segment as shewn
in Figure 19, or with the handle and the bevel-segment. When the said key is in
engagement with the shaft and the bevel-segment the handle will remain stationary,
a spring-catch fixed to a projection on the bearing p¹ serving to hold the said
handle against rotation.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what we
claim is :
1. In a breech-loading gun or piece of ordnance, mounting the breech-block in
an auxiliary ring capable of rotating within the carrier-ring, substantially as
described.
2. In a breech-loading gun or piece of ordnance having the breech-block
arranged to slide within an auxiliary ring as herein before described, the employ-
ment of a cam secured to the spindle upon which the carrier-ring is hinged or
pivotted and engaging with a pin or stud upon the auxiliary ring, substantially as
described.
3. In a breech-loading gun or piece of ordnance the arrangement of a rack and
pinion for withdrawing the breech-block from the breech in combination with the
box having the gear-teeth upon its exterior, substantially as described.
4. In a breech-loading gun or piece of ordnance, the combination of a breech-
block provided with a rack, a pinion mounted upon the spindle or hinge-pin of the
carrier-ring and adapted to engage with the teeth of the said rack, and a cam-
cylinder secured to the said spindle and adapted to rotate therewith, all substantially
as described.
5. In a breech-loading gun or piece of ordnance, the breech-block of which is
adapted to be operated to unlock it by means of a cam and to withdraw it by means
of a pinion, the arrangement of screw-threads upon the operating spindle- for
5

page_text: permitting the unlocking cam to be operated without imparting movement to the
pinion for withdrawing the breech-block, substantially as described.
6. In a breech-loading gun or piece of ordnance, an extractor arranged to be
operated by a lever and eccentric, substantially in the manner described.
7. In a breech-loading gun or piece of ordnance the arrangement of mechanism
substantially as described with reference to Figures 1, 14, 15, 16, 17, 18 and 19 for
utilizing the force of the recoil for storing sufficient energy to effect the closing of
the breech, substantially as described.
8. In a breech-loading gun or piece of ordnance, the breech of which is adapted
to be opened or closed either by hand or by the force of the recoil, the arrangement
of mechanism, substantially as described with reference to Figure 19 for locking
either the recoil mechanism or the hand-lever to the operating gearing.
9. A breech-loading gun or piece of ordnance the breech of which is adapted to
be opened or closed by mechanism constructed and arranged substantially as
described with reference to Figures 1 to 9 of the accompanying drawings.
10. A breech-loading gun or piece of ordnance consisting of the parts constructed
and combined substantially in the manner hereinbefore described and illustrated in
the accompanying drawings and operating as, and for the purposes, set forth.
Dated the 22nd day of June 1891.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.