Improvements in Quick Firing Gun Mountings.
Year: 1893

page_text: Date of Application, 4th Aug., 1893
Complete Specification Left, 4th May, 1894-Accepted, 7th July, 1894
PROVISIONAL SPECIFICATION.
Improvements in Quick Firing Gun Mountings.
I, JOSIAH VAVASSEUR, of 8 Great George Street, in the City of Westminster,
Engineer, do hereby declare the nature of this invention to be as follows :-
This gun mounting so far resembles the well known Vavasseur mounting that
the gun runs out by gravity along an inclined slide and recoils under the control of
hydraulic cylinders forming part of the saddle on which the gun is carried by its
trunnions.
The gun slide is carried by a central cylindrical post firmly fixed to the deck.
The side cheeks of the slide are connected by cross frames in which are circular
apertures through which the post passes and which it fits. There is a pivot pin
which bears on to the top of the post, it passes through a spring cross bar fixed to
the cheeks of the slide and it is screwed down until it just lifts the slide so that
the gun can move freely about the pivot.
When the gun is fired the recoil brings the cross beam of the slide down to the
deck and relieves the pivot from excessive pressure.
In some cases when the gun deck on which the mounting has to be fixed is weak
I continue the post down to the deck underneath the gun deck and fix it to a step
so that the downward thrust would be transmitted by the post to the next deck.
The present practice is to build a circular structure between the two decks--this is
both costly and obstructs the space.
One of the side cheeks of the gun slide is fitted with a shoulder rest by the aid
of which the gunner supports himself in position whilst working the gun so that
bis eye is aligned with the sights whilst the handles for elevating and training and
the pistol for firing are within easy reach of his hand. The sights are fixed upon
the gun and the rear sight is sufficiently far forward not to endanger the gunner
when the gun recoils. The hand wheel for elevating the gun is geared by bevelled
pinions with an axis mounted on the gun slide and parallel to the incline along
which the saddle travels. This axis has a spur pinion upon it, and gears with
another similar pinion which can slide with groove and feather along its axis.
This axis is mounted upon the saddle and has a worm upon it engaged with a worm
wheel and this is on the same axis with a pinion which gears with an arc of teeth
fixed upon the gun. The hand wheel for training the gun is upon an inclined axis
carried by the slide and at its lower end it is connected by bevelled pinions with
an horizontal transverse axis. On this axis there is a worm and this worm is
engaged with worm teeth upon a ring fixed upon the central pillar.
Dated this 3rd der of August. 1893.
J. VAVASSEUR.
COMPLETE SPECIFICATION.
Improvements in Quick Firing Gun Mountings.
I, JOSIAH VAVASSEUR, of 8 Great George Street, in the City of Westminster,
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 gun mounting so far resembles the well known Vavasseur mounting that
the gun runs out by gravity along an inclined slide and recoils under the control

page_text: yu
uc cylinders forming part of the saddle on which the gun is carried by
its trunnions.
The gun slide is carried by a central cylindrical post firmly fixed to the deck
The side cheeks of the slide are connected by cross frames in which are circular
apertures through which the post passes and which it fits. There is a pivot pin
which bears on to the top of the post, it supports a spring cross bar fixed to the
slide and it is screwed down until it just lifts the slide so that the gun can move
freely about the pivot.
When the gun is fired the recoil brings the cross beam of the slide down to the
deck and relieves the pivot from excessive pressure.
In some cases when the gun deck on which the mounting has to be fixed is weak
I continue the post down to the deck underneath the gun deck and fix it to a step
so that the downward thrust would be transmitted by the post to the next deck.
The present practice is to build a circular structure between the two decks--this is
both costly and obstructs the space.
One of the side cheeks of the gun slide is fitted with a shoulder rest by the aid
of which the gunner supports himself in position whilst working the gun so that
his eye is aligned with the sights whilst the handles for elevating and training and
the pistol for firing are within easy reach of his hand. The sights are fixed upon
the gun and the rear sight is sufficiently far forward not to endanger the gunner
when the gun recoils. The hand wheel for elevating the gun is geared by bevelled
pinions with an axis mounted on the gun slide and parallel to the incline along
which the saddle travels. This axis has a spur pinion upon it, and gears with
another similar pinion through which an axis can slide with groove and feather.
This axis is mounted upon the saddle and has a worm upon it engaged with a worm
wheel and this is on the same axis with a pinion which gears with an arc of teeth
fixed upon the gun. The hand wheel for training the gun is upon an inclined axis
carried by the slide and at its lower end it is connected by bevelled pinions with
an horizontal transverse axis. On this axis there is a worm and this worm is
engaged with worm teeth upon a ring fixed upon the central pillar.
In order that my said invention may be fully understood and readily carried
into effect I will proceed to describe the drawings annexed.
Figure 1 is an elevation of a gun mounting in accordance with my invention:
the gun is shown in position and also the shield, the latter being represented partly
in section.
Figure 2 is a plan of the mounting, together with the gun and shield and
Figure 3 is a rear elevation of the same parts; a small portion of Figure 3 is in
section.
a is the gun. is the saddle with the bearings in which the trunnions of the gun
are held.
ce are the side cheeks of the slide on which at e' c¹ are inclined surfaces
and up these inclines the saddle & travels when the gun recoils. dd are the piston
rods of the hydraulic apparatus by which the recoil is controlled, they are fixed at
their fore ends to the slide. dare pistons on these rods working within cylinders
forming part of the saddle. This hydraulic apparatus being of a well known type,
it is unnecessary to describe it in detail.
The side cheeks c c are firmly connected by cross frames and the armour plate
shield e and the housing are also carried by the slide the supports by which they
are thereto connected being elastic. are massive cross frames situate one above
the other and connecting the side cheeks e; these cross frames are bored to receive
the upper end of the solid cylindrical pivot post g which is firmly fixed in the deck
immediately beneath the gun and it may when necessary be continued down to a
second deck below. On the top of the post g a cavity is formed and it receives a
coned pivot pin . is a spring steel cross bar which bears upon the pivot pin /
and are screw.bolts passing through the upper cross frame and through the

page_text: ends of the spring cross bar i; they receive nuts which are screwed up until the
pivot pin takes the weight of the gun and mounting and lifts the bearing
projections just clear of the deck or rather of suitable supporting surfaces
provided thereon.
This arrangement allows the gun to move very freely in training as the friction
is confined almost entirely to that of the pivot pin h upon the top of the post g. At
the same time the pivot pin is not exposed to undue violence when the gun is fired,
for at this time the recoil forces the slide downwards, the spring bar i yields and
the mounting seats itself on the supporting surfaces c thereby relieving the pivot
pin and in part also relieving the strain upon the pivot post g.
The pivot post g
has a wheel or disc k fixed upon it, and this has teeth with which a worm on the
horizontal axis 7 carried by the slide engages. Bevilled pinions connect the axis
with the inclined axis m on which is the hand wheel m' to be turned for the purpose
of training the gun.
On the same side of the gun and fixed to the slide there is a shoulder rest,
indicated at n against which the gunner leans and so steadies himself as he looks
along the sights and works the hand wheels m' and o' to bring the gun to bear.
The hand wheel o' is upon an axis o mounted upon the slide and this by bevilled
pinions is geared with the axis p which is parallel with the slide face that is to say
with the direction in which the saddle is compelled to travel during the recoil.
The axis p carries a toothed wheel it engages with another similar wheel y'
which is also mounted on the slide in such a way that its axis q may slide through
it with groove and feather. The axis y near its rear end is carried in bearings on
the saddle and here it has upon it a worm which gears with a worm wheel and so
drives a pinion which is mounted either fast or by frictional connection upon the
same axis with the worm wheel. This pinion r works into a toothed arc s fixed to
the gun and concentric with the trunnion. By this train of gear the gun is elevated
or depressed when the hand wheel o' is turned. is the pistol which fires the gun,
it also is fixed to the slide, it operates by the closing of an electric circuit which
causes the ignition of the cartridge priming. u is the fore sight and is the rear
sight, these sights are mounted upon the gun and project through apertures in the
shield and housing; they are seen through a sighting port at w. Provision is
made for sighting from either side of the gun by providing a duplicate sighting port
at w¹.
The handles for working the gun are it will be seen all in a position convenient
for use by the gunner whilst standing by the side of the gun in a forward position
such that he is well covered by the shield and housing and is well out of the way of
the men who work the breech mechanism. The gunner may stand either on the deck
or on a platform carried on the slide. There is no inconvenient displacement of the
handles, for the slide or part on which the handles are mounted does not partake of
the movement of the gun either in recoil or in elevation and depression. The
connection between the handle o' on the slide and the arc of teeth s on the gun is
nevertheless constantly maintained and this is done by the sliding axis which is
parallel to the slide face c' and which moves with the saddle when the gun recoils
and runs out.
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. A gun mounting substantially as described and represented by the annexed
drawings.
2. A gun mounting substantially as described in which the moving, parts are
supported by a stationary cylindrical post and by a pivot pin bearing centrally upon
the top of the post and by a cross frame or frames with a circular aperture through
which the post passes and which it fits.
3. A gun mounting substantially as described in which a spring bar and a pivot
pin seated upon a suitable support carry the moving parts of the mounting in such

page_text: manner that when the gun is fired the spring bar yields to the recoil and relieves
the pivot pin.
4. A gun mounting in which training and elevating gear substantially as described
is mounted upon the gun slide with the handles in position to be worked by the
gunner whilst aiming and in which a sliding or telescopic axis carried by the saddle
and parallel to the slide face transmits the movement of the elevating handle to a
pinion engaged with a toothed are upon the gun.
5. A gun mounting with training and elevating gear substantially as represented
by the annexed drawings.
J. VAVASSEUR.