Improvements in Mounting Guns on Board Ship, and in Gun Mountings generally.
Year: 1890

page_text: Date of Application, 21st Feb., 1890
Complete Specification Left, 19th Nov., 1890-Accepted, 20th Dec., 1890
PROVISIONAL SPECIFICATION.
Improvements in Mounting Guns on Board Ship, and in Gun
Mountings generally.
I, JOSIAH VAVASSEUR of the London Ordnance Works, Bear Lane, Southwark in
the County of Surrey, Engineer, do hereby declare the nature of this invention to be
as follows:-
The gun is as heretofore made capable of recoiling in a frame or cradle preferably
made cylindrical as has heretofore been proposed. The forward end of the cylindrical
cradle I make to lie within a slot formed vertically across the top of a solid
cylindrical block and provide it with horizontal trunnions which with their bearings
are slid into recesses in the block and secured by wedges or other means or I secure
the cradle by pivots inserted through the block.
The bottom of the block rests on the top of a pedestal fixel to a deck and the block
has a vertical pivot descending from it into bearings in the pedestal around its outer
edge it also carries clips to clip a flange which projects outwards from the top of the
pedestal and prevents lifting. Instead of employing the cylindrical block I in some
cases support the gun in ordinary bearings formed in brackets made on the vertical
pivot and surround these brackets with a circular armour plate or the block might be
made of spherical form with the vertical pivot projecting downwards from the lower
part of the sphere. When a mounting of this kind is to be used on board a ship
an opening is formed through the ships side just large enough to permit of the
pedestal and cylindrical block being placed in the opening so that the line of the
vessels side would pass centrally through them or approximately so. The portion of
the pedestal which is outside the side of the vessel is supported by a projecting sponson.
The sponson has an armour plated wall rising up around its outer edge nearly to the
level of the bottom of the gun. At the ends of the sponson the walls where the gun
when trained to one or other side will not come in contact with them may rise higher
and be bent inwards and made to meet the circumference of the cylindrical pivotting
block of the mounting. The recoil cylinder is situated preferably above the top of
the cylindrical cradle it is set concentrically within a casing and in the space between
the two is a coiled spring or springs for running the gun out after recoil or by
another arrangement 1 employ two cylinders to absorb recoil placed one on either
side with the cylindrical spring case centrally between them. This allows the axes of
the recoil and spring cylinders being placed at a minimum distance froui the axis of
the gun.
"
The rod or rods of the piston of the recoil cylinder is secured to an arm on
the rear end of the gun-this arm is also coupled by a roi or rods to a disc which
rests against the end of the coiled spring.
I provide preferably two sight bars one on either side of the gun and carried above
the top of the casing containing the recoil cylinder and spring. The two parallel bars
carrying the sights on either side of the gun are by preference attached together.at
their rear end and they can be slidden backwards or forwards as desire in guides
on a plate which by a clamp is coupled to a table on which the plate rests.
The table
when two sights are used passes across the top of the cradle and rests on curved
guides which are fixed to the upper part of the cra:lle. The table and the sight bars
which it carries can in this way be set at any desired angle to the central line of the
gun according to the elevation desired.
A sighting port or ports are formed through the ships side through which the sight
bars can be protruded these sight openings are the only openings through which
shot could enter and being above the gun and at a considerable height above the deck
the men working the gun are very efficiently protected.

page_text: The training of the gun is effected by turning the vertically pivotted cylindrical
block or arm and cradle support by suitable gear and the elevating of the gun by
elevating gear carried by the cradle and by this block or support.
CARPMAEL & Co.,
Agents.
COMPLETE SPECIFICATION.
Improvements in Mounting Guns on Board Ship, and in Gun
Mountings generally.
I, JOSIAH VAVASSEUR of the London Ordnance Works, Bear Lane, Southwark in
the County of Surrey, 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 gun is made capable of recoiling in a frame or cradle made similarly to what
has heretofore been proposed. The forward end of the cradle I make to lie within
a slot formed vertically across the top of a cylindrical block and provide it with
horizontal trunnions which with their bearings are slid into recesses in the block and
secured by lock screws with interrupted threads, wedges or other means or I secure
the cradle by pivots or trunnions inserted through the block.
The bottom of the block rests on the top of a pedestal fixed to a deck and the block
has a vertical pivot descending from it into bearings in the pedestal. Around its outer
edge it also carries clips to clip a flange which projects outwards from the top of the
pedestal and prevents lifting. Instead of employing the cylindrical block I in some
cases support the gun in ordinary bearings formed in brackets made on the vertical
pivot and surround these brackets with a circular armour plate or the block might be
made of spherical form with the vertical pivot projecting downwards from the lower
part of the sphere. When a mounting of this kind is to be used as a between deck
or broadside mounting on board a ship an opening is formed through the ship's side
just large enough to permit of the pedestal and cylindrical block being placed in
the opening so that the line of the vessel's side would pass centrally through them or
approximately so. The portion of the pedestal which is outside the side of the vessel
is supported by a projecting sponson. The sponson has an armour plated wall rising
up around its outer edge nearly to the level of the underside of the gun when at its
maximum depression. At the ends of the sponson the walls, (where the gun when
trained to one or other side will not come in contact with them) may rise higher and
be bent inwards and made to meet the circumference of the cylindrical pivotting block
of the mounting. I employ two cylinders to absorb recoil placed one on either side
below the gun with the cylindrical spring case above the gun. This allows of the axes
of the recoil and spring cylinders being placed at a minimum distance from the axis
of the gun.
Or the recoil cylinders and spring may be above the gun which allows of a
minimum height from deck or platform to centre of gun. There may be two recoil
cylinders and the spring placed centrally between them, or one cylinder and spring on
the same axis.
I provide preferably two sight bars one on either side of the gun and carried above
the top of the cradle, the sight bars can be set at any desired angle to the central line
of the gun according to the elevation desired.
A sighting port or ports are formed through the ships side through which the sight
bars can be protruded, these sight openings are the only openings through which shot
could enter and being above the gun and at a considerable height above the deck the
men working the gun are very efficiently protected.
When the mounting is placed on the upper deck of a ship it is protected by a
suitable outer shield attached to and turning with the mounting. This shield has a
lower opening in it through which the gun works and two sighting ports above through
which the sight bars protrude.

page_text: Figure 1 is a side elevation. Figure 2 a rear elevation. Figure 3 a plan and
Figure 4 a part sectional plan of a gun mounting constructed as above described, and
placed in a broadside or between deck position.
Figure 5 shews a side elevation partly in section of the mounting as modified for
being placed on the upper deck of a ship. Figure 6 is a plan of the same.
Figure 7 is a horizontal section of part of the same shewing how the trunnion
bearings may be retained by readily removable blocks or wedges.
Figure 8 is a vertical section shewing how the trunnions may be fixed in the
cylindrical block and enter recesses in the cradle.
In Figures 1, 2 and 3 A is a cylindrical block either in one solid piece or formed of a
circular base with a cylindrical armour plate rising up from it around its circum-
ference and also with uprights rising up from it to carry the bearings for the trunnions
of the cradle. B is the gun capable of sliding end wise within a tubular cradle C.
The forward end of the cradle lies within a slot cut across the top of the block and its
trunnions C are received in bearing blocks (which lie within the block but can be
drawn out backwards from it. The bearing block carries within a recess formed in
one side of it a screw C" the threads of which are cut away on one side. The screw
can be turned by a key applied to its end. When the side from which the screw
thread is cut away is outwards there is no projection from the bearing block but if a
half turn is given to the screw its threads then project outwards and interlock into
corresponding grooves or recesses in the cylindrical block to which the bearing block
is thus locked. The bearing blocks may also be locked, each by two screws formed
as described one at the top and one at the bottom. When the bearing blocks are
unlocked from the cylindrical block the gun and cradle together with its trunnion
bearings can be drawn backwards and removed from the mounting.
The cylindrical block rests around its circumference upon the top of a pedestal D
of about the same diameter, it bas also a central vertical pivot descending from it
which enters a corresponding circular recess in the pedestal and rests on springs
contained in this recess. Between the springs and the bottom of the recess is a
plate E resting on a ring of anti-friction balls or rollers. The springs take the greater
part or the whole of the weight of the gun, cradle and mounting so that there may be
but little friction between the cylindrical block and pedestal near the outer circum-
ference. To prevent the springs lifting the cylindrical block so high as to bring the
clips T into hard bearing against the flange of pedestal the plate has a central stem
rising up from it through the vertical pivot of the cylindrical block and has a suitably
adjusted nut screwed on to its upper end.
F is part of a ships side having an opening formed through it just large enough
for the pedestal and cylindrical block to be placed in so that approximately one half of
the block and pedestal may be outside the ships side.
G is a sponson on the outer side of the ships side to support the portion of the
pedestal which is outside the ship. H is an armour plated wall rising up around the
edge of the sponson nearly to the level of the bottom of the gun.
Above this level the plates forming the wall are bent inwards as shewn at Figure 3
so as to meet the circumference of the cylindrical block. In this way the opening in
the ship's side is completely filled in.
I I are the two hydraulic recoil cylinders on the underside of the tubular cradle at
its rear end.
J is a cylindrical casing containing springs for running the gun out after recoil,
it is carried on the top of the rear end of the cradle. B₁ are arms on the rear end of
the gun to which the piston rods of the recoil cylinders are attached and B' another
arm to which is secured a rod which at its front end has a disc upon it which bears
against the springs contained within the casing J.
KK are sight bars carried by tubular bearings K' which are jointed at K³ to
arms K³ which project from the top of the cradle. K are sight openings formed through
the ships side through which the sight bars are made to project so that when in
use the back sight may be within or in close proximity to the opening when the gun
is at right angles to the ships side or wall,

page_text: The sight bars K can be slidden backwards through the bearings K' when out of
use the arms K³ can also be slidden back so as to withdraw the bearings K¹ and
joint K2 from the sight opening and allow of the opening being closed. It also
admits of the sight har being moved backwards or forwards so that into whatever
direction the gun may be trained the back sight may be brought within or close to the
sighting port. The back sight may either be upon the bar or upon the bearing K'.
The sight bar can be inclined to any desired extent to the cradle by turning a pinion S'
carried by an arm S which extends rearwards from the bearing K-the pinion gears
into a curved toothed rack carried by the arm K³.
The pinion S' works against a light friction sufficient to keep the arm S in any
desired position. In order to prevent the sight bars K being inadvertently turned
down to such a position as would cause them to be injured by fouling the sighting
port or upper port sill of gun a projection S' is made on the arm S, the upward
movement of which beyond a safe limit is prevented by the overhead stop V, and the
yielding of the arm S to pressure.
Arrangements can also be made to prevent similar risk from the bars being raised
too high.
The training of the gun is effected from either side of the mounting by a worm L
gearing into the teeth of a rack formed partly around the circumference of the
pedestal D. The axis of the worm L is carried by downward projections from the
cylindrical block A and has upon it at each of its ends a bevil wheel M into which gears
a pinion N¹ on an axis N which also is carried in bearings by an arm projecting from
the cylindrical block. The axis N has a hand wheel N on its upper end by which it
can be turned.
The elevating of the gun is effected by a curved toothed rack 0 on the cradle into
which gears a pinion P₁ on an axis, P. On this axis is also a worm wheel P³ held to
it by a friction clip. Qis a worm gearing into the worin wheel, the axis of the worm
can be driven through bevil gear from the axis of a hand wheel R. The bearings for
these axes are carried by the arm which projects rearwards from the cylindrical
block A.
In the modification of the mounting shewn at Figures 5, 6 and 7 and adapted for
use on the upper deck of a ship the circular swivelling block A carries a shield W
with sighting ports W' for the sight bars K to be protruded through.
.These figures also shew how the bearings C2 for the trunnions C₁ of the cradle (may
be retained within the cylindrical block A by blocks or wedges X which can be drawn
out sidewise from the block.
These figures also show that the hydraulic recoil cylinder and cylinder containing
the running out springs may both be above the gun and in a line with one another, as
in other mountings before made by me.
In the modified way shown at Figure 8 of supporting the cradle C within the
cylindrical block A, the trunnions might be passed through holes in the sides of
the block A and made to enter recesses in the sides of the cradle.
Y are screws for retaining the trunnions in their place. Z is a screw screwing
through the centre of the trunnion. When the screws Y are removed the trunnion
can be withdrawn by screwing in the screw Z and making its end bear against the
side of the gun. This figure also shews that the hydraulic recoil cylinders may be
on either side of the cylinder containing the running out springs and all the cylinders
be carried above the gun.
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 combination of the opening through the ships side-the vertically
swivelling circular block and the pedestal on which it rests, fitting into the opening-
the sponson with armour wall around its edge, surrounding the portion of the pedestal
that projects through the opening-the slot formed through and across the cylindrical
Glock the cradle lying in the slot, supported on trunnions carried by the block-and

page_text: the sight bar or bars carried by the cradle and protruding through a sighting port or
ports formed through the ships side.
2. The combination of the circular vertically swivelling block, fitting within an
opening formed through an armour wall or ships side, and having a slot formed
through and across it in which lies a gun cradle the trunnions of which are in a plane
passing through the blocks axis or approximately so, so that the block fills the
opening in the wall or ships side, and the end of the cradle fills the opening through
the block or nearly so, and a sight bar or bars carried by the cradle, and protruding
through a small sight port or ports so that the back sight may be within or close to
the sighting port, when the gun is at right angles to the wall or ships side.
3. The combination of the circular vertically swivelling block fitting within an
opening formed through an armour wall or ships side and having a slot formed
through and across it in which lies a gun cradle, the trunnions of which are supported
by the block in a plane passing through the blocks axis or approximately so, so that
the block fills the opening in the wall or ships side, and the end of the cradle fills the
opening through the block or nearly so.
4. A gun mounting consisting of the circular vertically swivelling block having
a slot formed through and across it, the gun cradle lying in the slot, the cradle
trunnions supported by the block in a vertical plane passing through the block's axis
or approximately so, and the sight bar or bars carried by the cradle above the gun
with the back sight also in a vertical plane passing through the blocks axis or
approximately so.
5. A gun mounting consisting of the circular vertically swivelling block having
a slot formed through and across it, the cradle lying in the slot, the trunnions
projecting sidewise from the cradle, the bearings for the trunnions slid from the rear
into recesses in the block and locking bolts for locking the bearings into the recesses
in the block.
6. A gun mounting consisting of the circular vertically swivelling block, having
a slot formed through and across it, the cradle lying in the slot, and turning upon
horizontal trunnions which are in a vertical plane passing through the blocks axis or
approximately so.
7. A gun mounting consisting of the circular vertically swivelling block, the
cradle lying in the slot, the trunnions projecting sidewise from the cradle, the bearings
for the trunnions sli! from the rear into recesses in the block and bolts with
interrupted screw threads upon them for locking the bearings into the recesses in the
block.
8. The combination of the cradle the gun capable of sliding endwise therein, two
cylinders placed one on either side below the gun to absorb recoil and spring casing
placed centrally between them above the gun substantially as described.
9. The construction of gun mountings substantially as herein before described.
DL: 101 1
T
1000
J. VAVASSEUR.