improvements in and rerating to Dree-
Year: 1895

page_text: Tallot),
Date of Application (in United Kingdom), 19th Dec., 1895
Complete Specification Left, 19th Dec., 1895-Accepted, 4th Apr., 1896
improvements in and rerating to Dreeсп-шеопатіюш
I, JEAN BAPTISTE GUSTAVE ADOLPHE CANET, of 87 Avenue Henri-Martin,
Paris, in the Republic of France, 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 :-
This invention relates to improvements in breech-mechanism such as that
described in the Specification of former Letters Patent dated April 5 1894
No. 6815.
One of the most important of the present improvements consists in the peculiar
construction of the breech-block which is so formed that one of its limiting surfaces
assumes the outline of a portion or segment of a sphere, or, more generally, a portion
of a surface of revolution which surface fits a recess of corresponding shape in the
rear or breech end of the gun and is retained therein by a series of co-axial fillets
or rings concentric with the axis about which the breech-block oscillates in its
opening and closing movements.
The arrangements which I prefer to employ in carrying my invention into
practice are represented in the accompanying drawings, in which
Figure 1 is a vertical longitudinal section shewing the breech closed;
Figure 2 is a vertical longitudinal section shewing the breech open;
Figure 3 is a horizontal longitudinal section shewing the breech closed; and
Figure 4 is a rear end elevation thereof.
Figure 5 represents a modified form of the apparatus shown in Figures 1 to 4.
Like letters indicate corresponding parts throughout the drawings.
The breech-block B has the shape of a spherical segment limited by two vertical
truncated parts or faces CD CD provided with a series of concentric fillets or
rings EE, which fit between corresponding fillets FF provided in the rear end of
the gun. The base of the block has in it a semi-cylindrical recess G H.
The immediate result of this improved form of breech is that the block B is
capable of rotary movement about a transverse axis extending through the centres
of the two series of co-axial fillets or rings E, F, such movement, for the purpose
of closing the breech, being limited by an abutment or stop K (Figures 1 and 2).
The breech-block has a transverse cylindrical part E and integral with it or
attached to it an operating lever J provided with a shoulder I (Figure 3)* which,
when it meets a corresponding shoulder or stop on the breech end of the gun,
limits the movement of the block for the purpose of opening the breech. The
cylindrical part E is located within a recess forming a bearing, for it in the rear
or breech end of the gun, the axis of which recess or bearing is that about which
the breech-block turns in opening and closing the breech.

page_text: For the purpose of locking the breech in the closed position, a handle N, subject
to the action of a spring O, is made to slide upon the end of the operating lever,
and is provided with a tooth P which, when the breech is closed, enters a recess or
chamber Q, in the gun, in which recess it is retained by the spring O. In order
to turn the lever J to open the breech, it is necessary, first, to press the handle N
so as to release the tooth P from its recess Q.
The firing mechanism comprises a firing pin a having a head b which is recessed,
or formed with a chamber, for the reception of a detent e and its spring d; the
detent is controlled by a sear e, adapted to move about a pivot f. The sear has
an operating arm 9 and is provided with a roller by means of which it presses
upon the arm k of the main spring which, by its other arm 7 ucts directly upon the
firing pin.
The double-armed extractor mm (Figure 3) is adapted to oscillate about the
pivot n (Figures 1 and 2) and is provided with a tail piece p which is subject to
the action of the shoulder or raised portion L of the breech-block at the termination
of the opening movement of the latter.
The operation of the above described improved breech mechanism is as
follows:-
Assuming the mechanism to be in the position shown in Figure 1, the gunner
presses upon the handle N, compresses the spring O and disengages the tooth P
from its recess Q. He then turns down the lever J, to the rear of the gun.
During this movement the breech-block controlled by its co-axial fillets or rings E,
turns about the transverse axis passing through the centre of the said rings, until
arrested by the stop or shoulder on the breech end of the gun. The breech-block
is then in the position indicated in Figure 2, the rear end of the bore being fully
open and accessible for loading. At the termination of this movement, the
projection or shoulder L of the breech-block strikes the tail-piece p of the
extractor which is thereby actuated to eject the empty cartridge case from
the barrel. After loading the gun, the gunner turns the lever J in the direction
opposite to that of its former movement, thereby closing the breech. Then, to
ignite the charge, he pulls the lanyard, which has been previously attached to the
lever and passed through an eye or ring at r (Figures 1 and 2) The arm g is
thereby actuated to move the sear about the pivot f in contact with the detent
until the escapement of one from the other of these parts takes place. The main
spring, having been thus compressed, now acts upon the firing pin a, which bas
been disengaged from the sear and drives it against the cartridge or primer. It is
obvious that the position of the ring or eye r may be varied as required.
Ignition can take place only when the breech is properly closed and locked for
at, and not before, that moment will the firing pin a be in the position for igniting
the charge.
Referring to Figure 5 the parts drawn in full lines represent a form of breech
generally similar to that above described, but wherein the spherical segment is not
truncated by two vertical sides such as CD, CD, and wherein the co-axial or
concentric fillets or rings are formed on the spherical surface.
The parts, shown in the same figure in dotted lines illustrate a modification
wherein the fillets or rings are formed upon a surface which is larger at its forward
than at its rear portion.
It will be understood moreover, that the hereinabove described improved breech
is capable of various other modifications. For example the breech-block may have
the form of a truncated pyramid the base of which is a segment of a spherical
surface which is the forward or inner end of the block. In this case the block
requires no fillets or rings.
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 construction of a breech block the forward surface of which is a spherical

page_text: surface or surface of revolution and the sides of which are vertical planes provided
with concentric or coaxial fillets or rings adapted to fit and turn in correspondingly
shaped recesses in the end of the gun, substantially as described with reference to
the accompanying drawings, for the purpose specified.
2. The modifications of the said invention described with reference to Figure 5,
that is to say, the form of block wherein the spherical segment is not truncated and
also the form of block wherein the fillets or rings are formed on a surface which is
smaller at the rear than at the forward portion of the block.
3. The modification of the said invention wherein the breech-block is formed
without the aforesaid fillets substantially as specified.
4. The combination with the above described breech-block of the locking, firing,
and extracting mechanism substantially as hereinabove described with reference to
Figures 1 to 5.of the accompanying drawings.
5. The combination, with a gun, of a breech-block which opens and closes the
breech by turning about a transverse axis concentric with fillets or rings on the
block which engage with similar fillets or rings in the gun, for the purposes
specified.
Dated this 10th dow of December 1805
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.