Improvements in Gun Mountings.
Year: 1885

page_text: Improvements in Gun Mountings.
I, JOSIAH VAVASSEUR of the London Ordnance Works Southwark in the
County of Surrey Engineer do hereby declare the nature of this invention to be
as follows:-
This invention has for its object improvements in gun mountings.
The lower portion of the gun mounting pivots either at its fore end or about a
pivot centrally arranged as the case may require. It is supported on training
rollers and is worked by training gear in the same way as an ordinary slide.
There are standards upon this lower portion of the mounting and these receive
trunnions formed upon a guide frame within which the gun is able to recoil. At
its fore end the guide frame carries an armour plate shield with a hole or
embrasure through which the gun projects. The guide frame at its rear end is
supported by elevating screws passing through trunnion nuts jointed to the guide
frame. On the elevating screws at their lower ends are bevelled pinions engaging
with corresponding pinions upon a horizontal axis which receives its notion from
a hand wheel through suitable gear-Or in place of employing elevating screws
with nuts racks and pinions may be used but less conveniently.
The recoil of the gun is controlled by hydraulic compressors, the cylinders of
these are preferably secured to the gun by clips passing around it. The piston
rods pass out from the cylinders at their fore ends and are fixed to the armour
plate shield or to the fore part of the guide frame. Springs are also provided
which are compressed by the gun when it recoils.. The springs are arranged upon
rods or spindles fixed to the armour plate shield, and lugs upon the clip which
secures the hydraulic cylinders to the gun abut upon these springs. Suitable
arrangements in connection with the hydraulic compressors prevent the return of
the gun after recoil from being too violent or if preferred, separate hydraulic
cylinders may be provided to control the return of the gun to the firing position.
Preferably the compressor cylinders are secured one on either side of the gun
and the cylinders form the blocks to travel in the guides of the trunnion frame
when the gun recoils, and afterwards returns by the operation of the springs. The

page_text: buffer springs are of sufficient power and range to return the gun to the firing
position even when elevated to a bigh angle and to maintain it there.
The firing position to which the gun is brought by the reaction of the springs is
controlled by stops fixed to the shield or to the guide frame and these stops are
adjustable, so that when the gun is forward the balance of the parts about the
trunnions may be such as to admit of the gun being elevated or depressed by a
moderate force applied to the elevating gear. In this arrangement it will be seen
that the recoil in no way interferes with the elevating gear and takes place in an
axial direction whatever may be the position of the gun when it is fired.
Dated this 21st day of December 1885.

page_text: I JOSIAH VAVASSEUR of the London Ordnance Works 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:-
This Invention has for its object improvements in gun mountings.
At
The lower portion of the gun mounting pivots either at its fore end or about a
pivot centrally arranged as the case may require. It is supported on training
rollers and is worked by training gear in the same way as an ordinary slide:
There are standards upon this lower portion of the mounting and these receive
trunnions formed upon a guide frame within which the gun is able to recoil.
its fore end the guide frame carries an armour plate shield with a hole or
embrasure through which the gun projects. The guide frame at its rear end is
supported by elevating screws passing through trunnion nuts jointed to the guide
frame. On the elevating screws at their lower ends are bevilled pinions engaging
with corresponding pinions upon a horizontal axis which receives its motion from
a hand wheel through suitable gear. Or in place of employing elevating screws
with nuts, racks and pinions may be used, but less conveniently.
The recoil of the gun is controlled by hydraulic compressors-the cylinders of
these are preferably secured to the gun by clips passing around it. The piston
rods pass out from the cylinders at their fore ends and are fixed to the armour
plate shield, or to the fore part of the guide frame. Springs are also provided
which are compressed by the gun when it recoils. The springs are arranged upon
rods or spindles fixed to the armour plate shield, and lugs upon the clip which
secures the hydraulic cylinders to the gun abut upon these springs. Suitable
arrangements in connection with the hydraulic compressore prevent the return of
the gun after recoil from being too violent, or if preferred, separate hydraulic
cylinders may be provided to control the return of the gun to the firing position.
Preferably the compressor cylinders are secured one on either side of the gun
and the cylinders form the blocks to travel in the guides of the trunnion frame
when the gun recoils; and afterwards returns by the operation of the springs.
The buffer springs are of sufficient power and range to return the gun to the
firing position even when elevated to a high angle and to maintain it' there.
The firing position to which the gun is brought by the reaction of the springs is
controlled by stops fixed to the shield, or to the guide frame and these stops are
adjustable, so that when the gun is forward the balance of the parts about the
trunnions may be such as to admit of the gun being elevated or depressed by a
moderate force applied to the elevating gear. In this arrangement it will be seen
that the recoil in no way interferes with the elevating gear and takes place in an
axial direction whatever may be the position of the gun when it is fired.
In order that my said Invention. may be most fully understood and readily
carried into effect I will proceed to describe the drawings hereunto annexed.

page_text: Figure 1 is a side view of a gun mounting.
Figure 2 is a plan of same.
Figure 3 is a rear end view.
Figure 4 is a half transverse section on line A. A. of Figure 1.
Figure 5 is a sectional plan of the compressor cylinder.
The lower portion of the mounting a. works on a centrally placed pivot formed
by the raised tubular portion b of the circular plate c, fixed to the deck or platform
on which the gun is mounted.
The mounting may also be arranged to work on a front pivot.
The base is supported on training rollers & and is trained from the hand
wheel e. through spur wheels ele es which drive the worm e gearing with the
worm,wheel e fixed on the tubular pivot b.
On the axles of the training rollers d are fitted clips f to prevent the lift of the
mounting when the gun is fired.
On the base a are placed standards g. provided with trunnion bearings g¹ which
receive trunnions h formed upon a guide frame h¹ within which the gun i, is able
to recoil. The gun is preferably made without trunnions and is held in a strap k,
forming part of the sliding blocks k¹. The guide frame h¹ is fitted with guiding
tongues on which the blocks / work and these serve to keep the guide frames
from spreading apart out of position when the gun is fired.
At its fore end the guide frame h¹ carries an armour plate
hole or embrasure through which the gun projects.
provided with a
The guide frame at its rear end is supported by elevating screws m passing
through trunnion nuts m¹ jointed to the guide frame at its upper part. The
nuts m' are split so that by means of the clamp nuts m' any play due to wear
may be suppressed.
.
The elevating screws work in bearings m³ capable of turning on the pivots m'
carried in bearings in the standard g. The lower ends of the elevating screws are.
provided with bevil pinions m³ engaging with corresponding pinions m³ upon the
horizontal shaft m'. This shaft is carried in bearings those at the outer ends
being formed on m³ and the inner bearing m³ being keyed on the ends of the
pivots m so that the whole of these bearings and the shaft m' with the bevil
wheel turn on the pivots m following the fore and aft movement given to the
screws m. as the nuts m' work up and down in the circular path described from
the centre of the trunnions h.
Motion is given to the screws m from the hand wheel m³ placed at the end of
the shaft mo sufficiently to the rear to be clear of the gun at the end of recoil.
The shaft m drives the bevilled pinion m₁ gearing with the corresponding
pinion m¹² on the horizontal shaft m'. The shaft m⁰ is by preference made so as
to be readily removed by fitting into a socket m¹³ in which it is clamped by the
bolt m. The bearing m¹s for the shaft m¹ is formed on the inner bearing m³ of
the horizontal shaft m7.
In place of using screws for elevating as shown by these drawings racks and
pinions may be employed but not so conveniently.
The recoil of the gun is controlled by hydraulic compressors the cylinders of
which are by preference secured to the gun and recoil with it. The cylinders may.
either be formed in one piece with the straps k, and guide blocks k¹ or may be
inserted in those blocks and secured by being screwed into them as shown or in
any equivalent way. The piston rods n' pass out of the cylinders at the fore end
and are secured by the nuts n³ ³ to the armour plate . or they may be secured to
the fore end of the guide frame k¹.
"
The arrangement of pistons and valves n' for controlling recoil I make by
preference according to my well known system that is to say I provide passages

page_text: in the pistons and discs to cover these passages. When the piston moves along
the cylinder the disc is turned around upon the piston by the operation of rifle
grooves within the cylinder so that during recoil the passages are progressively
closed.
Both the piston rods are arranged to act in tension during recoil.
The mounting is arranged so that at all angles of elevation the gun recoils in the
line of fire. To run the gun out again springs pare provided. These are com-
pressed during recoil by means of the brackets p₁ formed on the straps or sliding
blocks k¹. They are arranged upon rods p' secured at the fore end to the armour
plate or may be secured to the guide frame h¹. The necessary compression is
given to the springs p to keep the gun in the firing position, at the greatest angle
of elevation and to ensure its running out by means of the nuts p³. A plate p*
secured to the guide frame h¹ supports the rear ends of the rods p².
The firing position to which the gun is brought by the reaction of the springs is
controlled by the adjustable stop (one or more) fitted to the shield Z and guide
frame or placed in any other suitable position.
The springs may be arranged either to act directly as the drawings show or
indirectly through suitable levers or mechanism.
A circular shield with port. for the gun to pass through is shown secured to
the standard g by side wings ₁ giving additional lateral protection. Hinged
doors are provided in these wings to give access to the front of the mounting.
It is so arranged that when the gun is in firing position the balance of the parts
about the trunnions may be such as to admit of the gun being elevated or
depressed by a moderate force applied to the elevating gear. It will also be seen
that the recoil of the gun in no way interferes with the elevating gear.
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. The combination consisting of the pivotted under frame, the trunnion frame,
the gun which recoils along the trunnion frame and the springs which are com-
pressed during recoil and return the gun to the firing position.
2. The combination consisting of the under frame, the trunnion frame, the gun
which recoils along the trunnion frame and hydraulic compressors which control
the movement of the gun.
3. The combination consisting of the under-frame, the trunnion frame, the gun
which recoils along the trunnion frame the springs which return to the gun to
the firing position and the hydraulic compressors which control the movements of
the gun.
4. The combination consisting of the under frame, the trunnion frame, the gun
which recoils along the trunnion frame, and the elevating gear which connects the
trunnion frame and the under frame.
5. The combination consisting of the under frame, the trunnion frame, the
armour plate shield, fixed to the trunnion frame and the gun which recoils along
the trunnion frame.