Improvements in Gun Mountings.
Year: 1891

page_text: Date of Application, 4th Nov., 1891-Accepted, 19th Dec., 1891
COMPLETE SPECIFICATION.
Improvements in Gun Mountings.
I, JOHN BECHER ORMSBY, Colonel R.A. and GEORGE HENRY BANISTER,
Civil Engineer, both of the Royal Arsenal, Woolwich, in the County of Kent,
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 said invention partly relates to centrally pivotted gun mountings and com-
prises improvements whereby such mountings can be more readily moved for
horizontal adjustment or training, and more firmly supported at and immediately
after the time of firing the gun, than heretofore.
It also relates to improvements in hydro-pneumatic apparatus for controlling the
recoil of a gun and for restoring it after recoil to the firing position.
The gun is carried on guides in a cradle in or through which it slides, on recoil,
the movement being controlled by the aforesaid hydro-pneumatic apparatus. The
gun has no trunnions about which it is moved for elevation but the cradle is
supported by trunnions in the lower carriage and the elevation of the gun is varied
by moving the cradle about these trunnions. Therefore the gun always recoils
along the line of fire.
The said invention is illustrated in the accompanying drawings which show a gun
and mounting for high angle fire.
Figure 1 is a plan or top view.
Figure 2 is a side elevation partly in section.
Figure 3 is a longitudinal section of the hydro-pneumatic apparatus apart from
the gun-mounting.
Figure 4 shows a slight modification of the said apparatus.
Like letters indicate the same parts throughout the drawings.
C
a is a pivot-block or base-plate provided with a central pivot a¹ upon which the
lower carriage bis placed as shewn, c is the cradle, c¹ c¹ are the trunnions of the
cradle. d is an annular bearing surface on the pivot block and e is a bearing surface
on the lower carriage.
The whole mounting is rotated, in training or traversing the gun, about the
central pivot a' the carriage b being secured in place thereon by the socket b'.
An important feature of our invention is the provision for ensuring great freedom
of movement of the mounting about the pivot in training or traversing the gun.
For this purpose the upper surface of the central pivot a carries coned rollers f
arranged in a ring or circle as shown. By the employment of rollers running on a
path formed on the upper surface of the pivot we obtain the advantages of a roller-
bearing, within a very small diameter, these rollers are preferably solid without
axles or pins they support a disc or plate g, which is shaped on the under side to
bear evenly on the series of rollers. In some instances balls may be used instead of
these rollers f. Saucer shaped or Belleville springs h are placed on the upper surface
of the disc and by means of these springs the lower carriage has an elastic
yielding support upon the pivot. Through the top of the socket is passed an
adjustable screw plug i the lower surface of which is in immediate contact with one
of the springs h. By means of this screw-plug the carriage b can be slightly raised
or lowered relatively to the pivot. Moreover the plug i may be readily removed
to permit access to the springs which may thus be conveniently examined or
removed and replaced if necessary.
For ensuring great steadiness and solidity of the mounting at and immediately
after the time of firing without impairing the freedom of movement of the mounting
about the central pivot we provide the outer periphery of the pivot block and

page_text: These surfaces under
ordinary conditions and at all times except during the recoil are separated by a
slight space, the whole weight of the gun and mounting being then taken on the
central pivot, but under the stress existing during the recoil of the gun the springs h
are deflected so that the bearing surface e is forced into close contact with the
surface d. It will therefore be seen that by the arrangement of the central roller
bearing surface of small diameter, and the elastic or yielding support of the
mounting thereon in combination with the outer or peripheral bearing surfaces, we
provide for the training or horizontal adjustment of the gun with the expenditure
of very little power and also for the automatic action of the mounting whereby on
the firing of the gun it assumes the most advantageous position for resisting the
effects of the discharge and recoil.
lower carriage with the aforesaid bearing surfaces d and e.
The training or traversing of the gun is effected by means of the hand wheel k
through the medium of a chain 7 passing over a pulley on the hand wheel shaft and
around the periphery of the pivot block a to which it is attached.
″.
For elevation the cradle is moved about its trunnions as above specified. For
The boss of the hand
this purpose we provide the hand wheel m and screw n.
wheel forms a nut through which the screw passes; the said screw is pivotted by
one end to the cradle at n¹ and the nut is pivotted to the carriage b.
Our improved hydro-pneumatic apparatus is shewn in detail in Figures 3 and 4;
o is the cylinder is the piston p' is the piston rod p' is a hollow ram extending
from the piston through the packing gland o¹.
The piston nearly fits the bore of the cylinder o along which it slides in the
recoil and return movements of the gun, but a small annular space is left between
the ram and the bore of the cylinder o for a purpose hereinafter explained. When
applied to the mounting above described we use two cylinders placed on opposite
sides of the gun and in the plane of its longitudinal axis. The piston rods p¹are
connected at the end to the gun.
The action of the recoil apparatus is as follows, that is to say, the space sur-
rounding the piston rod is charged with oil or other liquid, while the interior of
the ramp contains air at a pressure sufficient to run out the gun when the same
has been adjusted to its maximum elevation about the cradle-trunnions c¹. During
the recoil movement the liquid below the piston passes through the orifice q in the
piston into the interior of the ram p² and further compresses the air therein.
The energy thus stored up is utilized to restore the gun to the firing position.
Moreover in the recoil a portion of the liquid below the piston passes by the
clearance space around the piston into the annular space around the ram p². And
in the running out of the gun the resistance due to the return of this liquid past
the piston to the lower end of the cylinder after recoil, serves to prevent violent
action in the return or upward movement of the gun.
Figure 4 shows a slight modification wherein the orifice is omitted and an
orifice is made at r above the piston through the side of the hollow ram p². In this
modification the bore of the cylinder should be so tapered or curved in longitudinal
section that there will be an annular space varying in area with the position of the
piston, around the periphery of the same the area of the space being at all times
such that a uniform resistance is offered to the movement of the piston during the
recoil of the gun.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is
First. The centre-pivot having its upper surface formed to serve as a roller-
path and having a circle or ring of rollers arranged thereon for the purpose
specified.
Second. A central pivot-bearing having a circle or ring of rollers whereon the
mounting is supported through the medium of a spring or springs and a disc.or
´plate, substantially as and for the purpose specified.

page_text: Third. Providing the top of the socket with the screw-plug or equivalent device,
substantially as and for the purpose specified.
Fourth. The herein described gun mounting centrally supported by a spring or
springs upon a circle or ring of rollers and having its central bearing arranged to
operate in combination with the outer bearing surfaces as and for the purpose
specified.
Fifth. The hydro-pneumatic apparatus consisting of the cylinder, the piston with
the rod extending through one end of the cylinder for attachment to the gun, and
the hollow ram formed on the piston and extending through the other end of the
cylinder and having an aperture for the passage of liquid in the recoil and return
of the gun all substantially as and for the purposes specified.
Sixth. In a gun mounting the combination of our improved hydro-pneumatic
apparatus with the gun and the cradle or upper carriage, substantially as described
with reference to the accompanying drawings and for the purpose specified.
Seventh. A gun mounting wherein our improved central pivot and hydro-
pneumatic apparatus are arranged in combination with the other parts of the
mounting substantially as described with reference to the drawings for the purposes
specified.
Deted this 4th doy of Navanihan 1201
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicants.