Improvements in the Breech Mechanism of Guns.
Year: 1891

page_text: Date of Application, 13th July, 1891-Accepted, 19th Sept., 1891
COMPLETE SPECIFICATION.
Improvements in the Breech Mechanism of Guns.
I, JEAN BAPTISTE GUSTAVE ADOLPHE CANET, of 91 Avenue Malakoff,
Paris, France, Civil Engineer, 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 :-
The present invention relates to various improvements in the breech mechanism
of guns, and consists in a new arrangement of parts for opening and closing the
breech, for firing the gun, and also in safety apparatus to prevent hanging fire and
the possible unfastening of the breech during firing.
Figs. 1 to 8 inclusive of the accompanying drawings illustrate my new arrange-
ment of parts for opening and closing the breech of guns,
Fig. 1 being an end elevation of a gun embodying my invention as applied to a
gun in which a metallic obturator is employed.
Fig. 2 is a longitudinal horizontal section of Fig. 1, when the breech is closed.
Fig. 3 a corresponding section of Fig. 1, when the breech is partly open.
Fig. 4 a vertical section through the gun showing one of the safety appliances in
detail, and
Fig. 5 a plan view of same.
Fig. 6 is an end elevation of a gun embodying my invention as applied to a gun
in which a plastic obturator is employed.
Fig. 7 is a longitudinal horizontal section of Fig. 6, and
Fig. 8 a vertical section of Fig. 6.
Figs. 9 to 29 inclusive of the drawings illustrate in detail the various
modifications of my improved safety appliances for preventing hanging fire and
the possible unfastening of the breech during firing.
Referring to Figs. 1 to 8 inclusive of the drawings
In screw breech closing mechanism which is operated by a handle, when it is
desired to open the breech the hand lever is first raised from the bottom upwards
so as to disengage from its notch the cam serving to prevent unfastening.
In the breech closing mechanism forming the object of the present invention I
utilize the movement of the hand lever to transform same from its commencement
into two successive movements of rotation and of sliding which are imparted to
the screw.
For this purpose the breech screw A (Figs. 1 to 5 inclusive) is provided at its
rear with a collar on a portion of which a sector with helicoidal teeth a is formed.
In one of the plain sections of the breech screw, and forming a continuation of
these teeth, is a rack b.
Upon the axis of the hand lever, which is arranged horizontally, a toothed
sector B is keyed. This sector carries helicoidal teeth c to gear with the teeth a of
the screw, and to communicate a rotary movement of th or th of a revolution
thereto. Following the helicoidal teeth are straight teeth d, which are caused to
gear with the rack 6 of the screw to communicate a sliding movement thereto.
To open the breech the hand lever C is drawn towards the operator. The
toothed sector B immediately begins to rotate, the helicoidal teeth of such sector
gear with the corresponding teeth a of the screw and communicate rotary
The screw
A
movement thereto, in a plane perpendicular to the axis of the gun.
makes its eighth or sixth of a revolution during the first part of the movement of
the hand lever. So that the fraction of a revolution which the screw ought to turn
may be exactly limited, at its rear the screw carries at its upper part a tail piece or
projection, which when the gth or the th of a rotation is completed butts against
a stop or abutment f formed on the bracket.

page_text: This fraction of a rotation being completed, the screw, therefore, can turn no
further. At this moment the first of the straight teeth has been brought into
contact with the first tooth of the rack b of the screw.
By continuing the movement of the hand lever the screw is therefore drawn
backward. When the screw A has been drawn back to the required extent, the
sector B butts against the stop of the hinge of tho bracket. The latter then
turns on its axis carrying the screw with it until the breech opening of the gun is
uncovered to allow the loading to be effected.
At the moment when, the screw having ceased to move backward, the bracket
begins to turn, a bolt causes the screw and the bracket to act as one piece, until in
closing the breech the screw and the bracket are brought back again to the same
place, when the bolt is released and the screw rendered free again.
When the loading has been effected the breech closed by the same means but
in the reverse direction.
For firing the breech screw carries at its forward end a firing pin and a spring
held in place by a nut. It is further traversed by a central rod y forming the
hammer.
At the end of this hammer is a cylindrical box in which is enclosed a small
piston, of which the head i is in the form of a catch, and also a spring. At the rear
end of the screw is hinged a lever K carrying a noser which is brought to engage
under the catch i of the piston.
A strong coil spring tends to always bring the hammer rod g back on to the
firing pin. The parts being arranged as described, if the lever K is drawn back by
its handle, the nose will force back the catch i, until the former describing an are
of a circle, the catch i will be released. The hammer rod being then violently
forced forward by its spring, will strike the firing pin, which produces the ignition
of the detonator.
As soon as the lever K is released it is brought back again under the action of
the spring pusher 1.. The piston i moves inwards to allow the noser to pass, and
all the parts then resume their original position.
In this position the firing pin has been moved back again for the next shot, so as
not to project beyond the front face of the breech screw.
S
This system of breech closing is provided with a double safety mechanism which
provents firing when the gun is not completely closed. For this purpose so long as
the th of a rotation has not been completed either in the action of opening or
closing the breech, the firing lever K cannot operate, because it carries a tail piece.
which bears against the bracket; but when in its sliding movement the screw
moves independently of the bracket, the lever becoming free the firing could be
effected unless a second precaution were provided by means of the pusher of the
lever. For this purpose the pusher is provided with an ear m which forms a pro-
jection outside the screw and enters a alot o in the bracket, in which slot it moves
during the rotation of the breech screw (Figs. 4 and 5), being capable of oscillating.
round its axis.
When the rotation of the screw is ended and the breech closed, the ear m has
been brought so that it bears against the lower end of the slot o. In this position
if the lever K is operated the ear m descends into a slot formed in the screw
parallel to its axis. When the breech is opened, the rotation of the screw being
completed, the ear m butts against the end of slot o and enters the portion of the
slot in the screw.
The firing lever can then be drawn away from the bracket, but nevertheless it
cannot operate as the pusher can no longer descend.
The preceding description only relates to closing mechanism for metallic rings
or obturators, but I' may also construct a system, analogous to the former, which
is specially applicable for employment with plastic obturators.
The principal parts or organs being the same, the opening and closing of the
breech is effected as before, but in this system the axis of rotation of the sector is
no longer the same as that of the axis of the bracket. This arrangement results

page_text: from the necessity of having to further remove the mechanism from the breech
opening. Further, the sector B carries only one helicoidal tooth and the screw
only a single slot in the case where the breech screw is of small diameter.
In the closing of breeches having plastic obturators, it is indispensable that it
should be impossible to introduce the friction tube into the priming hole if the
breech is not entirely closed, and if the operating lever is not secured so as to
prevent unfastening.
For this purpose I arrange a bolt V or cover (Figs. 6 and 7) carrying a part o
and which by being displaced laterally in a slide covers or uncovers the priming
hole, according to whether the lever is secured or not, that is to say, whether the
breech block is in the firing position or not.
The displacement of the cover is effected by the intermediary of a pawl L
carried by the operating lever, and it is this pawl which by entering a recess F
formed in the gun enables the lever to be fixed on the end of the gun, and to
prevent unfastening. It is mounted upon a piston P which slides in the lever and
is always acted upon by an opposing spring.
The operation of the cover of the securing pawl is as follows:-
The cover has a heel piece 1 which when the breech screw is not screwed home
is brought to engage a circular slot 2 (Fig. 8) formed for the purpose in the
bracket, and thus prevents any displacement. Near the end of the unfastening the
safety bolt 3 following the incline 4 (Fig. 8) under the action of its spring enters a
recess 5 formed in the cover, and renders the latter fixed when the screw has been
drawn outwards. The cover cannot therefore slide in its slot except when the th
or th of a turn is completed. This condition having been fulfilled, the lever is
then applied to the end of the gun, that is to say to the secured position; but to
bring it to this position it was requisite to force the pawl toward the centre of the
breech so as to be able to bring same in front of its seat. The pawl and the bolt
then towards the end of the closing occupy a series of positions having for their
object to bring the heel piece 6 of the pawl Lopposite its seat in the cover, then to
introduce same therein. When the pawl L is, under the action of the spring, able
to enter its seat E, the breech screw will be screwed right home, and the cover will
consequently be able to follow the pawl in its backward movement and to uncover
the priming hole more and more.
To open the breech it is first requisite to force back the piston P of the pawl,
80 as to cause it to leave its scat. The cover will follow its movement, and if the
The
lever is then operated the breech screw will immediately begin to unscrew.
heel piece 6 of the pawl will not however be completely disengaged from its seat
in the cover; the heel piece 1 will on the other hand be engaged in the slot 2 of
the bracket, and if the movement of the lever is continued, the pawl will return to
its position as soon as it can clear the gun, and that the pressure on the piston is
discontinued. The breech screw will first unscrew while the safety bolt enters the
cover, then it will be drawn back and finally carried along with the bracket.
The different improvements above described may be applied at will to the breech
closing of rapid firing field or naval guns of no matter what calibre, and generally
to the closing of all screw breeches with interrupted threads, by employing the
single movement of one part only, either a lever or not, and transforming same into
successive rotary and sliding movements.
The mechanism above described has for its object to enable the breeches of
ordnance to be opened and closed with very great rapidity.
In order to avoid all chance of accidents resulting from this rapidity of operation,
and from the reactions proceeding from the firing I have invented safety apparatus
forming an integral part of the complète system.
This apparatus has for its object to oppose the opening of the breech by ordinary
means so long as the charge has not been fired, and to render the description clearer
I have illustrated various modifications of such apparatus in Figs. 9 to 29 inclusive
of the accompanying drawings.

page_text: Fig. 9 is an end view of a gun fitted with such apparatus.
Fig. 10 a vertical section, and
Fig. 11 a plan view thereof.
The apparatus consists essentially of a two-armed catch 7 pivotted at a point on
the outer surface of the gun. One of its arms is by any suitable means connected
to a fixed point of the gun carriage or mounting, or terminates in a weight 8. The
other arm is provided with a hook which under the action of a leaf spring 9 engages
a slot 10 in the operating lever C of the breech.
Upon the recoil of the gun the catch turns either by reason of its connection
with the carriage or by the inertia of the weight 8; and a bolt 11 connected to the
operating lever and acted upon by an opposing spring, is brought to the position 11*,
so that it is in front of the end of the catch 7 which is then in the position 7*.
The breech can then be opened, but by this movement the bolt 11 in moving
back ward disengages the hook and permits the catch 7 to return to its original
position under the action of spring 9. When the closing of the breech is effected,
at the latter part of the closing operation, an inclined plane 12 formed on the
operating lever C, causes the catch 7 to turn owing to the inclined surface of the
hook, and this hook while forcing back the bolt 11 engages the slot 10, for its
oscillation has not been sufficient this time to permit the bolt 11 to operate.
Fig. 12 is an end view of a gun fitted with a modified form of the apparatus.
Fig. 13 a vertical section, and
Fig. 14 a plan view thereof.
This modification consists in a catch 7 articulated upon the operating lever and
having two, arms which perform the same functions as in the previous arrangement,
the hook of the second arm engaging a slot or recess 10 formed in the rear face of
the gun.
When the gun recoils the catch 7 turns, as in the former arrangement,
and the bolt 11, which in this case is connected to the first arm of the catch 7, enters
a seat 13 in the rear face of the gun:
The catch 7 being thus rendered fixed, the breech can be opened, but in doing
so bolt 11 is disengaged and the catch under the action of spring 9 resumes its
original position.
In the latter part of the closing operation, the bolt, in spite of the action of its
opposing spring, is forced back and the rear of the hook encountering an inclined
plane on the rear face of the gun, turns slightly and then enters the recess 10, the
oscillation not having been sufficient this time to enable the bolt to operate.
Fig. 15 is an end view of a gun fitted with another modified form of the
apparatus, and
Fig. 16 is a plan view thereof..
In this arrangement the catch 7 has three arins, one terminating in a weight 8 or
connected to a fixed point on the carriage; the second is provided with a book
which engages a small arm 14 of the operating lever, and the end of the third arm
bears against a spring 9, and is provided with a recess or seat 13.
When the gun recoils the catch oscillates and a projection 15 on the bolt 11
enters the recess 13, thus fixing the catch in the position 7*, where the hook no
longer arrests the operating lever. When, to open the breech, the support 16 is
drawn back, an inclined plane 17 on such support depresses the bolt 11, enabling the
catch 7 to return to its former position under the action of spring 9.
When the breech is reclosed, an inclined plane formed on the small arm of the
operating lever causes the catch 7 to oscillate sufficiently to cause it to become
again engaged, but not sufficiently to allow the bolt 11' to operate.
Fig. 17 is an end view of a gun fitted with another modified form of the
apparatus.
Fig. 18 a vertical section, and
Fig. 19 a horizontal section thereof.
In this arrangement the catch 7 is keyed to a screw threaded shaft 18, of which
the thread is of rapid pitch, and which works through a nut secured to the rear of

page_text: the breech. This shaft forms part of a rod, the two parts 19 and 20 of which are
connected by a nut 21, so as to only permit the part 20 to more vertically. A
spring 22 forces the lower end of this part into a recess in the operating lever.
The catch consists of two arms, one of which is provided with a weight or is
connected to a fixed point of the carriage, and the other has a rounded part which
bears against a bolt 11. At the moment of recoil the catch turns, and in so doing
by its vertical movement releases the operating lever.
•
At the same time, the bolt 11 under the action of its opposing spring passes
behind the second arm of the catch, which secures it in the position 7*.
When the breech is opened the bolt 11, which forms part of the bracket, forces
the catch to the position 7**, then clears same, and in so doing enables it to return
to its original position under the action of spring 22. When the breech is reclosed,
the operating lever by means of an inclined plane raises the rod 20. The shaft 18
then rises and turns sufficiently to enable the second arm of the catch to force back
the bolt 11, but not sufficiently to allow the bolt to operate. As soon as the rod 20
again descends into its recess, the catch resumes its original position.
Fig. 20 is a horizontal section of a gun fitted with a further modification of the
apparatus.
In this arrangement the catch 7 has three arms of which two perform the same
functions as in the first arrangement. The third arm carries a roller 23 which
moves along a double curved spring 24. During the recoil the roller passes from
one curve of the spring to the other, and the catch is held at 7*.
When the breech is opened a projection on the operating lever bears upon
the
back of the hook with which one of the arms of the catch terminates, and forces
the roller 23 to return to the first curve of the spring. The catch then resumes its
original position.
When the breech is closed again, a projection 25 on the operating lever and
having an inclined face, forces back the hook by causing the catch 7 to oscillate.
The hook then again becomes engaged, for its displacement has not been sufficient
to cause the roller 23 to pass from the first to the second curve of the spring.
Fig. 21 is a horizontal section of a gun fitted with a further modification of the
apparatus.
In this arrangement the catch 7 has two arms, but the second arm 26 has no
hook and simply enters a notch formed in the breech screw or in a collar of such
screw. During recoil the catch turns to the position 7*, disengaging the armı 26
which moves to 26*.
.
A heel piece 27 formed on the catch then fixes the latter by coming in contact
with the spring bolt 11, and the breech can be opened.
The breech being reclosed, the lever 28 is operated to effect the firing. In this
movenient the rod 29 is forced back against the action of its opposing spring, and
the arm 26 is brought back to its seat. The breech screw cannot therefore turn
during firing.
Fig. 22 is a horizontal section of a gun fitted with a further modification of the
apparatus.
In this arrangement during the recoil the catch 7 oscillates and its second arm 26
beara ngainst a slide 30 which it forces to the position 30%, so that it is impossible
for the catch to return to its original position.
In this movement; the axis of the catch has moved from 31 to 31*, and the
bolt 11 to which it is connected, has been disengaged from the body of the breech
screw.
The breech can, therefore, then be opened, but in such movement the bracket
in pivotting, brings the slide and consequently the catch back to their original
position:
During the closing movement the breech screw, owing to iuclines formed thercon,
forces back the bolt II' until, when the closing is completed, such rod again enters
its seat in the breach screw, which it prevents from turning.

page_text: opening 47 forined in the operating lever. When the gun recoils, the catch turns
and uncovers opening 47, at the same time that the bolt 11 enters a suitable seat in
the operating lever; the catch is thus rendered fixed. The breech can then be
opened, for the tail 45 of lever 44, 45,, can move in the opening 47, which has been
uncovered. But in turning the lever 44, 45, forces the bolt 11 out of its scat, and
the tail 45 of such lever then prevents the catch from returning completely to its
first position.
As soon as the opening movement begius another bolt 48, which
until then has continued to bear against a stop 49 fixed to the gun, becomes
disengaged from a seat formed in the tail 45 of lever 44, 45, and fixes this lever.
To reclose the breech it is only requisite to force back the handle of the operating
lever against the breech. The stop 49 then forces back the bolt 48 into its seat,
and the tail 45 of lever 44, 45, is depressed by the action of its spring 43.
The catch 7 being no longer supported against the tail 45 then resumes its
original position.
It will be readily understood that the arrangements above described might be
modified without departing from my invention, and further that the materials,
proportions, and the dimensions as well as the accessory arrangements may also be
varied, and I reserve to myself the right of so doing and of applying the safety
apparatus described to any system of guns and to breeches having either screw or
plain breech blocks.
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. The utilization of the movement of the ordinary haud lever of the breeches of
guns to directly produce the unscrewing of the breech screw, its movement in the
direction of the axis of the gun, and finally the turning of the screw and of the
bracket upon the axis of the latter, these successive movemente being effected by
the parts specified, but which may be improved and modified to suit the require-
ments and dimensions of different guns.
2. The discharge of quick firing guns in which the charge is either contained in
a metallic shell, or provided with a metallic bottom, by means of special mechanism
permitting the back return movement of the firing pin after discharge, and carrying
a safety apparatus against the unfastening of the breech, such apparatus preventing
firing before the breech is completely closed, substantially as specified.
3. The arrangement of a second safety apparatus on the same breech for
preventing firing in any other position than when the breech is entirely closed,
especially during the longitudinal movement of the breech block and the rotation
of the bracket, substantially as specified.
4. The arrangement whereby the opening and closing of the breech of guns in
which the obturation is assured by a plastic ring, is affected by a single movement
of a hand lever in the same direction, such arrangement being similar in its
principal parts to that covered in Claim 1, but in which two centres of rotation are
provided, one for the lever and the other for the breech screw and the bracket,
substantially as specified.
5. The special arrangement specified for firing with friction tubes, in which the
safety mechanism prevents prematuro firing.
6. The mechanism baving for its object to fix, at the moment of firing, a lever
with which the opening of the breech is entirely effected, or with which it is only
commenced, such mechanism consisting in
(a) A hooked lever engaging either a slot in the operating lever (as shown in
Figs. 9, 10 and 11), or in the rear of the breech (as shown in Figs. 12, 13
aud 14), or, seizing either a projection on the small arm of the operating
lever (as shown in Figs. 15, 16 and 25) or a projection on the large arın of
such lever (as shown in Fig. 20).
(b) A catch with a screw threaded stem of which the extremity enters a slot
in the operating lever (as shown in Figs. 17, 18 and 19),

page_text: 7. The mechanism having for object to prevent, at the moment of firing, the
commencement of the rotation of the breech screw, or the sliding of a plain breech
block, such mechanism consisting in a lever having two arms, one of which engages
a slot in the breech screw, such lever being caused to become engaged by the act
of firing itself (as shown in Fig. 21) and of a rod engaging the breech screw, either
in a line parallel to the generating lines (as shown in Figs. 23 and 24) or normally
to the axis of the gun (as shown in Figs. 22 and 25), substantially as specified.
8. The combination of two or more of such mechanisms together on the same
gun, substantially as specified.
9. The combination with the operating lever of all gun breeches of a safety
mechanism such as shown in Figs. 26, 27, 28 and 29, and which prevents the
spontaneous opening of screw or plain breeches under the interior action of the
gases generated by the powder.
10. The combination of one or more of these mechanisms with the safety
mechanism for preventing the spontaneous opening of the breech (Figs. 26, 27
and 28).