Improvements relating to the Breech Mechanism of Ordnance.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements relating to the Breech Mechanism of Ordnance.
I, MANASSAH GLEDHILL, Director of Sir W. G. Armstrong, Whitworth & Co.,
Tid.. of Oneshow. Manchester, in the County of Lancaster, do hereby declare the
nature of this invention to be as follows:-
This invention relates to breech mechanism for ordnance and is designed to
afford means for very readily closing and opening the breech. For this purpose
I construct the breech block in the form of a conical or taper plug having con-
tinuous or uninterrupted screw threads and I form in the breech end of the gun
a conical or taper cavity or chamber with corresponding screw threads. The
angle to which the block and chamber are tapered is such that a slight rotative
movement of the plug will be sufficient to cause its screw threads to be engaged
with or released from those in the gun. By reason of the continuity of the screw
threads I am enabled to use a comparatively short breech-block or plug. The said
taper block or plug is supported in a carrier hinged or pivotted in any convenient
manner at one side of the breech. The opening and closing of the said taper
block or plug are effected by means of an appropriately arranged handle or lever
which is preferably so geared with the plug that a movement of the said lever in
one direction will effect the unscrewing and release of the plug and the opening
of the breech, and the reverse movement of the said lever will effect the closing
and locking of the breech.
001
Nanamhon 1907
HASELTINE, LAKE & Co..
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.
I, MANASSAH GLEDHILL, Director of Sir W. G. Armstrong, Whitworth & Co.,
Ltd., of Openshaw, Manchester, in the County of Lancaster, 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 breech mechanism for ordnance and is designed to

page_text: Figure an end elevation and
Figure 3 a side elevation showing the breech of a gun provided with a conical
breech block or plug having a continuous screw-thread according to my invention
and so arranged as to effect the purpose of the said invention in respect of the
quick opening and closing of the breech.
The remaining figures are hereinafter described.
Like letters indicate the same parts throughout the drawings.
I will first particularly describe the apparatus shewn in Figures 1, 2 and 3.
A is the comical breech plug. B is the carrier which is hinged to one side of
the gun as shewn at B. Cis a toothed bar or rack which gears with the toothed
segment B on the breech plug and which is arranged to slide transversely in the
said carrier. D is a link for connecting the rack with the lever or handle E
which is hinged to the carrier at the lower end of the hinge pin. The periphery
of the breech plug is provided with a spiral or cam groove F: a pin or stud G
projects through the side of the carrier so that its inner end or point enters the
said groove. Through a portion of its length the angle of inclination of this
groove corresponds with that of the screw-threads of the breech plug so that in
the rotation of the block or plug the stud while in this position of the groove exerts
no endwise action on the block. But the remaining portion of the groove which
reaches the stud when the screw threads of the plug are released from those of
the gun has its inclination or pitch increased as shewn in Figure 3 so that by
continuing to turn in the same direction the plug will clear the threads of the gun
and can then be swung back to open the breech, this action of the groove and
stud being reversed in the closing of the breech.
By the use of this mechanism with a conical breech block having a continuous
or uninterrupted screw thread I provide in a very simple manner for completely
opening the breech by a short continuous movement of the handle in one direction
and for closing the breech by a similar movement of the said handle in the other
direction.
It will be observed that in Figure 1 I have shown the breech screw with a
multiple thread this being with the object of imparting to the plug a quick end-
wise movement relatively to its rotative movement, so that for being screwed into
or unscrewed from the breech the said plug only requires a partial rotation about
its axis such as can be imparted to it by a rack of convenient length as shewn.
In a breech mechanism of the class herein described it is necessary that the
carrier be held fast to the gun while the breech is closed. Also that the plug be
held immorably in the carrier while the breech is open.
I therefore arrange
on the carrier B a hook H which, when the breech is closed, engages with a

page_text: shoulder I of the gun and holds the carrier fast thereto but in the opening of the
breech the said hook at the end of the movement of the rack is released from the
said shoulder so that the carrier B can swing backward away from the gun.
Until the carrier begins to swing back on its hinge the plug is not made fast or
immovable in the said carrier but I provide for making it fast therein by means
of the spring catch bolt J which while the breech is closed is kept pressed back
in its socket by its contact with the end of the gun. But when the carrier begins
to swing back the said catch bolt is forced into engagement with a notch in the
breech plug and holds the same immovably in the carrier until it is again closed.
In the modification of my invention illustrated in Figures 4, 5, 6, 7, 8, 9
and 10 I have provided for the use of epicyclic gearing for operating my improved
conical breech plug in such a manner that the breech can be opened or closed by
one complete revolution of the plug about its axis.
Figure 4 is a top view and Figure 5 an end elevation of the breech mechanism.
Figure 6 is a plan, l'igure 7 an end elevation and Figure S an end view of
the carrier detached from the gun.
Figures 9 and 10 are respectively an end elevation and a plan of the breech
plug detached from the carrier.
The plug A is mounted upon the screw-threaded central pin B3 of the carrier B.
The toothed segment is in this instance a separately formed ring B which is sup-
ported in the carrier and geared with the transversely moving rack C also mounted
in the carrier. To one end of the said rack C is connected the lever or handle E
which is also connected to the link E', the latter being pivoted to a convenient
part of the carrier. The said handle and link form a toggle-system which is very
advantageous for operating the rack C. Or any other convenient arrangement
of the lever may be employed.
The epicyclic gearing is as follows, viz.—there is an outer stationary toothed
ring K attached to the carrier in any suitable manner, and a "live
ring L
which is rotatable about the axis of the plug and is operated through the agency
of the pins
or studs B on the toothed segment B. This live ring carries the
two pinions M, which are geared with the stationary outer ring K and with the
pinion A on the breech plug A. Therefore by manipulating the handle E
the required movements for opening or closing the breech are transmitted through
the rack, the toothed segment and the epicyclic gearing to the breech-plug A and
the latter by being turned about its axis not more than one revolution can have
its screw threads completely interlocked with or released from those of the gun.
For locking the segment to the carrier I provide the latter with the following
device is a spring-catch or pivoted lever having arms N' Nº. One arm N¹
when the breech is closed enters a recess in the gun at N and the other arm N
then lies in the path of a shoulder or projection at the side of a notch in the
segment B. In rotating the segment for opening the breech the said shoulder
strikes the arm N and raises the arm N out of the said recess at the moment when
the breech-plug screw-threads are clear of those of the gun. The carrier B is
then free to turn on its hinge and as it swings hack the spring-catch is forced into
a notch in the carrier while the arm N3 remains in the notch of the segment.
This device ensures the retention of the segment and breech plug in the proper
position in the carrier while the latter is moving about its hinge in the opening
or closing of the breech and the release of the segment from the carrier when
the latter is closed. Then the segment in its rotation in the reverse direction raises
the arm N, the arm again entering the recess in the gun and thereby again
locking the carrier to the latter.
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 ordnance the employment of a conical or taper
screw plug having a continuous or uninterrupted thread as shewn in combination

page_text: with mechanism for operating the said plug substantially as described with refer-
ence to Figures 1, 2 and 3 for the purposes specified.
2. The modification of my invention wherein I employ a conical continuously
screw threaded breech-block operated by a rack through the agency of epicyclic
gearing substantially as described with reference to Figures 4, 5, 6, 7, 8, 9 and 10
for the purposes set forth.
Dated this 28th day of September 1908
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.