Improvements in Breech Mechanisms for Guns.
Year: 1889

page_text: Date of Application, 29th Oct., 1889
Complete Specification Left, 18th Aug., 1890-Accepted, 29th Oct., 1890
PROVISIONAL SPECIFICATION.
Improvements in Breech Mechanisms for Guns.
AXEL WELIN. Scandinavian Sailors Temperance Home, Garford Street, London, E.,
Mechanical Engineer and Honorary Manager of the above Institution do hereby declare
the nature of this invention to be as follows:-
For closing the breech of a gun, I use two screws, one behind & resting against the
other. the one being right hand threaded, the other left hand threaded or if both are
threaded right or left the threads are running with different pitches. In either caso
I insert a locking piece through the outer screw, locking that one to the other, the
screws having been pushed or screwed into coinciding threads provided in the breech.
The screw against which the cartridge is pressed when fired is at least so much
smaller than the other that it can enter the part of the breech where threads are
provided for receiving it without touching the tops of the threads made for the other
screw. The gun being fired the pressure of the gas in the chamber tends to force the
screws rearward. These being guided by the threads running in reverse directions or
with different pitches, at the same time locked to each other by the aforesaid locking
piece are thus prevented from moving.
The locking piece I prefer to provide with a threaded pin extending rearward to
receive the cylindrical part of a lever, (provided with coinciding threads), by which I
suggest to operate the whole mechanism.
Moreover I provide a ring close behind the breech end of the gun, for receiving the
rearmost screw (breech-screw) when the breech is to be opened. This ring can be
hinched and the bolt round which it is made able to turn I prefer to provide with
quick threads and to make moveable only in the direction of its own axis."
With this construction, when to open the breech, the locking piece is withdrawn by
means of the aforesaid lever, the rearmost breech screw screws itself backwards,
bringing the other breech screw with it, a stud or friction roller on the free end of the
lever, (in continuing the turning motion of the same) is caused to bear against the
lower end of the hinch bolt and to lift it upwards, which is thus, by means of its quick
threads, brought to turn the carrier ring, now carrying the breech screws, to one side,
leaving the breech of the gun fully open.
Datoil this the 90th day of October 1889
COMPLETE SPECIFICATION.
Improvements in Breech Mechanisms for Guns.
1, AXEL WELIN, Scandinavian Sailors Temperance Home, Garford Street, London, E.,
Mechanical Engineer and Honorary Manager of the above Institution, 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:
For closing the breech of a gun, I use two screws, one behind and resting against
the other, the one being right hand threaded, the other left hand threaded or if both
are threaded right or left the threads run with different pitches. In either case [
may insert a locking piece through the outer screw, locking that one to the other.
The screws are pushed or screwed into corresponding threads provided in the breech.
The screw against which the cartridge is pressed when fired is at least so much
smaller than the other that it can enter the part of the breech where threads are
provided for receiving it, without touching the tops of the threads made for the other
screw. The gun being fired the pressure of the gas in the chamber tends to force
D
17

page_text: the screws rearward. These being guided by the threads running in reverse directions
or with different pitches, at the same time locked to each other are prevented from
moving.
The locking piece I prefer to provide with a threaded pin extending rearward to
receive the cylindrical part of a lever (provided with corresponding threads,) by which
I operate the whole mechanism. Moreover I provide a ring close behind the breech
end of the gun, for receiving the rearmost breech-screw when the breech is opened.
This ring can be hinged and the bolt round which it is made able to turn-I prefer
however to provide the bolt with quick threads and to make moveable only in the
direction of its own axis.
With this construction, when it is desired to open the breech, the locking piece is
withdrawn by means of the aforesaid lever, the rearmost breech screw screws itself back-
wards, bringing the other breech screw with it. The continued turning motion of
the lever lifts the hinge bolt upwards, which thus, by means of its quick threads,
causes the carrier ring, now carrying the breech screws, to turn one side, leaving the
breech of the gun fully open.
In order that my said invention may be more fully understood and readily carried
into effect I will proceed to describe the drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a rear elevation of a gun constructed according to my invention.
Figure 2 is a horizontal longitudinal section with the locking piece withdrawn.
A is the rear breech-block and B the front breech-block. The block A is provided
with a quick threaded right hand screw and the block B with quick threaded left
hand screw.
These screws engage with corresponding screw threads on the inside of
the breech of the gun. a is the obturator whose stem passes through the wad and
the two breech blocks into the hollow threaded pin or stem A² which carries the
locking piece A. This locking piece consists of three arms which carry bolts passing
through the block A and entering recesses in the block B. C is the breecli-
block carrier and D is the handle for operating the parts. The stem A² has three
longitudinal grooves A³ in it which receive feathers upon the handle D, so that
when the handle D is turned the stem A³ also turns but is free to slide rearwards
through it. At A' A' the grooves A³ on the stem A² are connected together by
circumferential grooves. The breech block carrier C is mounted upon a bolt c whose
upper end is provided with a quick threaded screw, as shown in Figure 1, and its
middle with a rack c¹ whose teeth gear with a toothed sector d pivotted at d to the
breech-block carrier C. This sector is double and its other teeth gear with tho
teeth of a pinion E fixed to the handle f is a spring locking bolt carried by the
block A. The bolt c is provided with feathers which prevent it from turning but
allow it to move up and down.
The firing mechanism is of ordinary construction and is not shown in the drawings.
The action of the apparatus is as follows
:-
In order to open the breech the handle D is turned, the first effect of this is to
draw the locking piece A' rearward for it cannot turn until it is free from the
block B and it therefore acts as a nut upon the screw thread at the forward end of the
stem A. When the locking piece A¹ has been fully withdrawn it comes to the end
of the screw thread upon the stem A2 as shown at Figure 2 and therefore as the handle
continues to revolve it turns with it as it is now free to do carrying the breech-block A
also round, thereby unscrewing it from the breech. As the block A is unscrewed it
moves rearward carrying the block B with it, the block B turning independently
of A and unscrewing itself from the breech. When the breech-blocks are freed the
two circumferential grooves A in the stem A have come opposite to the lugs D' on
the handle, so that the latter is now free to turn independently of the stein A²; the
teeth upon the pinion E now come into gear with the teeth of the segment d causing
the segment to revolve about its axis d¹, thereby lifting the pin c and causing the
quick threaded screw upon it to revolve the breech block carrier and so opening the
breech.

page_text: SHOW
L momed gun. Figure is a rear elevation the breech
being open.
Figure 4 is a longitudinal section (on the line 1, 1, Figure 3) the breech being
closed.
Figure 5 is a longitudinal section of the gun with the breech blocks and mechanism
connected therewith removed.
Figure 6 is a rear elevation, Figure 8 a front elevation, and Figure 7 a
longitudinal section (on the line 2, 2, Figures 6 and 8) of the breech block
carrier.
Figure 9 is a rear elevation, Figure 11 a front elevation, Figure 10 a longi-
tudinal section (on the line 3, 3, Figures 9 and 11) and Figure 12 a side elevation of
the rear breech block.
Figure 13 a rear elevation, Figure 15 a front elevation, Figure 14 a longitudinal
section (on the line 4, 4, Figures 13 and 15) and Figure 16 a side elevation of the front
breech block.
Figures 17 and 18 are a front view and plan of the firing pin.
A is the rear breech block, its periphery is furnished with a helically divided
screw of an ordinary type which engages with a corresponding screw on the
inside of the breech of the gun in the usual manner. B is the front breech block
whose periphery is furnished with a quick threaded screw which engages with a
corresponding screw upon the inside of the brocch of the gun. The pitch of this
quick threaded screw is the same as that of the helical segments on the block A. The
two blocks are connected together by means of a dovetailed projection A' upon the.
block A which engages with a corresponding recess in the bleck B. The projection A¹
is in the form of a ring, two opposite quadrants of which have a rectangular section
whilst the other two quadrants are undercut, see Figures 10 and 11. The groove in
the block B is formed in a corresponding manner, as shown in Figures 13 and 14, so
that when the two blocks are put together and one of them turned they are locked
together. The block B has an overhanging lip B₁ which takes hold of the rim of the
cartridge and acts as an extractor.
The block A carries at its rear a hollow stem A2 which passes out through the
breech block carrier C, as shown in Figure 4. The stem A has longitudinal grooves
upon it to receive projections D¹ on the handle D, so that when the handle is turned
the block A turns with it, but is also free to move longitudinally along its axis. The
breech block carrier C has an overhanging lip C at its rear to keep the handle D in
place and it has fixed to it projections (which slide in guides E, E, upon the rear
of the gun.
Its inside is furnished with helical lugs C³ which enter grooves in the
breech block A. The firing pin F and its spring are contained in the hollow stem A²
of the block A.
.
The firing pin is provided with a lug F¹ which rides upon an incline G in a recess
at the rear end of the block B.
When the firing pin is in its forward position it cannot turn relatively to the
block A as the projection F fits in the slot H but this slot is widened at its rear so
that when the firing pin is drawn back it can turn slightly relatively to the block A
and when so turned is caught by the shoulder H¹ in the slot H and is retained in the
cocked position.
The action of the apparatus is as follows.
In order to open the breech after the gun has been fired the handle D is turned
thereby turning the breech block A causing the segments of its divided screw to
disengage from the corresponding divided screw in the breech of the gun. This
turning motion at the same time to a slight extent withdraws the block A from the
breech carrying the block B with it, which through its overhanging lip B₁ starts the
empty cartridge case. The turning of the block A relatively to the block B causes
the lug F on the firing pin F to ride up the incline G and so cocks the gun.
moment the divided screw on the breech-block A has been disengaged from the divided
screw in the breech the lug F' has reached the top of the incline and has passed onto
the shoulder H and comes against side abutments on the blocks A and B preventing
At the

page_text: the block A from rotating independently of the block B, so that, as the handle is
continued to be turned the two blocks are rotated together. The effect of this is that
the block B by reason of its quick threaded screw has a rapid rearward motion
imparted to it and the block A moves with it which it is free to do as the pitch of
the screw thread upon the block B is the same as that of the helical spaces between
the screw segments on the block A. When the two blocks have been fully withdrawn
into the carrier the latter with the blocks is caused to slide to one side along the
guides E into the position shown in Figure 3, the empty cartridge case is then
removed, a fresh cartridge is put in and the breech closed by reversing the
movements above described. When the two blocks are nearly home the screw threads
on the block A engage with the corresponding threads in the gun and the block A
nows turns faster than the block B the latter being forced home by the longitudinal
thrust of the former. During this motion the lug F¹ is retained in the notch H¹ and
is turned clear of the incline G in the block B so that it is free to be forced forward
by its spring and fire the gun when it is pushed off H. The gun is fired by the
line K which pulls the inclined slide L to one side giving an endway movement to
the rod M which pushes the lug F1 off the shoulder H³.
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 breech mechanism for guns the combination of two blocks one behind the
other which engage with different screws on the gun so that in opening and closing
the breech the blocks rotate independently of each other.
2. In breech mechanism for guns the combination of two blocks one behind the
other and so connected that they can turn relatively to each other but move longi-
tudinally together and which engage with different screws on the gun so that in
opening and closing the breech the blocks rotate independently of each other.
3. Breech mechanisms for guns substantially as described and shown in the
drawings.
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1000