Improvements in Breech-loading Ordnance.
Year: 1891

page_text: COMPLETE SPECIFICATION.
Improvements in Breech-loading Ordnance.
We, GREGORY GERDOM, of West Troy, in the County of Albany, Inventor,
and JOHN HENRY REYNOLDS, Manufacturer of Troy, in the County of Rensselaer,
both in the State of New York, United States of America, do hereby declare the
nature of our invention for IMPROVEMENTS IN BREECH-LOADING ORDNANCE,
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 improvements in breech-loading ordnance, and it relates
especially to the construction of the breech and breech-block of this class of
ordnance.
The object of our invention is to simplify the construction, and to render the
operations of opening and closing the breech less complex than in the ordinary
mode of construction. We attain this object by means of the mechanism
illustrated in the accompanying drawings, which are herein referred to and form
part of this Specification, and in which
Figure 1 is a horizontal longitudinal section of part of the breech of a cannon
provided with our improvements, with the breech piece and carrier-ring secured in
position to close the breech of the cannon shown in plan view.
Fig. 2 is a like section, showing the breech-piece in position to open the breech
of the cannon.
Fig. 3 is a rear-end elevation of Fig. 1.
Fig. 4 is an end elevation in outline of the breech of the cannon without the
breech-piece; and
Fig. 5 is an outline transverse section of the breech-piece detached from the
carrier-ring.
As heretofore commonly constructed breech-loading ordnance the breech of
the cannon and its breech-block have been provided with corresponding sections of
screw-threads and the breech-block has been fitted to receive an endwise sliding
movement in a carrier-ring hinged to the rearmost end of the cannon; and that
construction has required three movements of the breech-block, to wit; a partial
rotation to effect the engagement, or disengagement, of its screw-threads from those
in the breech of the cannon, an endwise sliding movement into, or out of, the
opening of the breech, and a swinging movement on the hinge-joint of the carrier-
ring, and these three movements are required to effect either an opening or closing
of the breech of the cannon. By our invention the end wise sliding movement of
the breech-block is dispensed with, thereby a saving of two movements is effected
every time the breech of the cannon is opened and closed.
As represented in the drawings, A designates the breech of a breech-loading
cannon having an enlarged chamber B, at its rear end, the axis of said chamber
coinciding with that of the bore of the cannon; the upper and lower sides of said
chamber are provided with segmental-sections of screw-threads C, whose length is
preferably made equal to the length of the chord of an arc of ninety degrees of a circle
whose diameter equals the larger diameter of the screw-threads; a lateral opening D,
whose height is equal to the length of the cord above referred to, is formed in one
side of said chamber, the opposite side of the latter is divested of screw-threads
and has a concave surface for a space which corresponds to the height of said
opening, and the length of said opening equals the length of the screw-threaded
portion of said chamber; the outer part of said opening, at the side of the cannon
s lengthened to form part of the hinge-joint for a carrier-ring. E is the breech-
lock having a screw-threaded portion F, which corresponds to the screw-threads C
ormed in the chamber B of the breech of the cannon; said threaded portion is

page_text: flattened by the removal of segments from its opposite sides to reduce the
thickness of said threaded portion to correspond to the height of the opening D,
through which said portion of the breech-block is fitted to swing with freedom; the
inner end of said breech-block has a coniform extension F¹, which enters a
tapering enlargement of the rearmost end of the bore of the cannon; said
coniform extension is provided with a gas-check G, of a common and well known
construction, which forms a gas-tight stopper for the bore of the cannon at its rear-
most end; but, it should be understood, said gas-check forms no part of our
invention, and any other form of gas-check may be substituted therefor when
preferred. Near the outer end of said breech-block just beyond the threaded
portion F, a cylindrical portion of said block is fitted to turn loosely in the bore
of a carrier-ring H, in which said breech-block is constantly retained; said
cylindrical portion of the breech-block is provided with a short groove, I,—
shown by dotted lines in Fig. 2-which conforms to the angle of the screw-
thread on said breech-block, and into said groove the point of a screw .J, enters
to limit the rotative movement of the breech-block and to prevent the latter from
being accidentally detached from the carrier-ring H. The screw J is screwed
into the carrier-ring H to form a permanent part thereof, and the groove I is
enlarged at the end which stops the rotative motion of the breech-block in the
operation of screwing the latter into the cannon breech, and by this enlargement,
the carrier-ring H and screw J are relieved from the danger of being damaged by
reason of any shock due to the explosion of the charge in the cannon. The outer
end of the breech-block E is enlarged to form a head K, which has a greater
diameter than the bore of the carrier-ring H and which projects rearwardly beyond
the outer face of said ring; said head is provided with lugs, L, to which a locking-
lever M is hinged by means of a hinge-pin N, and said locking-lover affords the
means for turning the breech-block E in the operations of screwing and unscrewing
the latter into and out of the breech of the cannon. The locking-lever M is
provided with an opening or indentation O for receiving a spring-catch as herein-
after explained. The carrier-ring H is provided with an arm P, which is integral
with it, and which extends at right angles from its inner face for the purpose of
forming a hinge-joint for said carrier-ring with the breech of the cannon; said arm
enters a forward extension of the opening D and forms a hinge-joint therein by
means of a joint-pin Q, which passes through the hole in said arm and corresponding
holes in the breech of the cannon.
By means of the arm P, the carrier-ring H is provided with an off-set hinge,
which extends forwardly into the opening D and thereby provision is made for
swinging the breech-block E through said opening directly into the chamber B,
into a position where the screw-threads of said breech-block can properly engage
with the screw-threads in said chamber, and, by this means, the sliding movement
commonly required for engaging the screw-threaded breech-block in the breech of
a cannon is rendered superfluous. The outer face of the carrier-ring H is provided
with lugs R, between which the locking-lever M enters to effect the locking of the
breech-block E, and one of said lugs is preferably provided with a spring-catch S,
or other suitable fastening, that is fitted to engage in the opening O, or other part
of said lever, for the purpose of securing the locking-lever in position to lock the
breech-block in the breech of the cannon. The carrier-ring H has a handle T, on
its outer face, preferably on the side opposite to the arm P, for the purpose of
affording means for swinging the carrier-ring and breech-block on the joint-pin Q.
Our invention operates in the following manner: Premising that the breech-
block E is screwed into the breech of the cannon and is locked therein, by the
locking-lever M, as shown in Fig. 3, the latter is first drawn out from between the
lugs R and turned upward into a position where it will serve as a lever for
the purpose of unscrewing the breech-block; when the latter has been unscrewed,
the carrier-ring H is swung, by means of the handle T, to carry the breech-block E
into the position shown in Fig. 2, whereby the bore of the cannon will be opened
for the reception of ammunition at its breech, and in said position the inner end of

page_text: the flattened sides of the breech-block will be retained in the opening D―whereby
said breech-block will be prevented from rotating in the carrier-ring H―ready for
its return into chamber B, and when the latter is accomplished a quarter revolution
is imparted to said breech-block-by means of the lever M-to screw the breech-
block home in the breech of the cannon, then the lever M is swung downward, and
caught by the spring-catch S, to lock the breech-block E in its closed position.
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. The combination of a breech-loading cannon having a breech-chamber of a
greater diameter than the bore of the cannon; said chamber being provided with
Begmental sections of screw-threads, and having a slotted opening which leads
radially from one side of said chamber through the perimeter of the breech of the
cannon the diameter of said opening being substantially the same as the chordal
length of the segments of said screw-threads, and a breech-block embracing a
cylindrical portion and a screw-threaded portion; the latter having a cross-section
form of the zone of a cylinder whose minor diameter is fitted to swing loosely in the
slotted opening of the breech and whose major diameter is provided with segmental
sections of screw-threads fitted to engage in the screw-threads in said breech-
chamber, substantially as herein specified.
2. The combination of a breech-loading cannon having a breech-chamber
provided with segmental-sections of screw-threads and having a slotted opening
which leads radially from said chamber through the perimeter of the breech of said
cannon the diameter of said opening being substantially the same as the chordal
length of the segments of said screw-threads, a breech-block embracing a cylindrical
portion and a screw-threaded portion which has the cross-sectional form of the
zone of a cylinder, whose minor diameter is fitted to swing loosely in the slotted
opening of said breech and whose major diameter is provided with segmental
sections of screw-threads fitted to engage in the screw-threads of said breech-
chamber, and a carrier-ring-in which said breech-block is fitted to partially
rotate-provided with an arm projecting perpendicularly from one of its plane
faces; said arm forming an off-set hinge-joint whereby said breech-block can be
swung into, and out of, said breech-chamber, substantially as specified.
3. In a breech-closing mechanism for ordnance, the combination of a carrier-
ring provided with a stop-screw whose point projects into the bore of said ring,
and a breech-block fitted loosely in said ring and provided with a groove into
which the point of said stop-screw enters, and whereby the rotative movement
of said breech block is limited in both directions; one end of said groove being
enlarged, as and for the purpose herein specified.
4. In a breech-closing mechanism for ordnance, the combination of a breech-
block fitted to be secured into the breech-chamber of a cannon by means of screw-
threads, and having a locking-lever hinged thereto whereby said breech-block may
be rotated, of a carrier-ring provided with a locking-mechanism whereby said
locking-lever can be secured to retain said breech-block in position in said breech-
chamber, substantially as herein specified.
Dated this 28th day of April 1891.
F. W. BARKER,
Applicants' Agent.