Improvements in Gun Mountings.
Year: 1891

page_text: Date of Application, 17th Mar., 1891
Complete Specification Left, 17th Dec., 1891-Accepted, 23rd Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements in Gun Mountings.
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:-
This invention relates more especially to the mounting of quick firing guns
where the gun is carried in a cradle having trunnions which are received into
bearings upon a shield or support capable of turning to admit of the gun being
trained upon the target.
In such and in other cases it is frequently required that the gun should be
capable of being readily mounted and dismounted, so that it may be stowed away
conveniently when out of use and when required may be again mounted ready for
service without loss of time.
For these purposes I secure the trunnion bearings to the shield or other support
in the following manner :-The support is recessed to receive the bearing which
slides into its place in an horizontal direction from rear to front. The support is
so formed as to confine the bearing so that it cannot escape from its place
laterally. Projecting forward from the bearing near the bottom there is a lug
which fits into a corresponding recess in the support and at the back of the bearing
there is a heel projecting downwards. This heel is made of a hook like form and
engages with the rear end of the support.
When the bearing is in position it is locked by placing behind it a block having
transverse teeth on its underside which enter corresponding grooves formed in
the support in rear of the bearing. A screw locking bolt passes down through
the block and enters a corresponding screw threaded hole in the support. The
screw threads may be cut away in segments so that a part of a turn only is
required to lock and to release. The screw secured to the block by means of
a garter groove and keys. In the head of the screw there is a socket to receive
a lever by which to turn it. In order to lift the screw locking bolt when the
threads are disengaged, a stem with rack teeth upon it is provided upon its head,
with this a toothed arc engages. An arın projecting rearwards from the bearing
carries the axis of the arc and on this axis there is a hand lever, means are also
provided for firmly clamping this lever in position.
To force the bearing home to its place upon the support I joint to the latter a
strap carrying a screw which if need be can be applied behind the bearing. A
few turns of this screw thrusts the bearing forward to the full extent.
By these means the gun and mechanism can be very rapidly placed in position
on the support and the bearings fixed with that solidity which is essential and they
can be removed with equal facility. All the parts required for fixing the
bearings are secured to them so that they cannot be carried away or mislaid.
Sometimes in place of arranging the toothed locking block behind the bearing
I fit it into a recess therein and I so arrange that the locking block may be raised
up into the recess to disengage the teeth and lowered down to make them enter
the grooves in the support. The block for this purpose is provided with a screw
stem projecting upwards. There is a nut upon the screw stem and this is held in
a piece of dovetail or other form fitted into a corresponding groove in the upper
surface of the bearing in rear of the trunnion-or the piece may be otherwise
attached to the bearing.
The nut has a flange upon its under side and the dovetail piece is recessed on
its under side to receive the flange. The nut is thus prevented from moving end-
wise but is able to turn freely. At its upper end the nut has a head keyed upon

page_text: it in which are recesses to receive a lever for turning the nut. Between the
flange of the nut and the recessed surface of the dovetail piece are a pair of
spring washers tending to keep the locking block down on its seat in case the
trunnion bearings lift in consequence of any small vertical play particularly when
the gun is fired at depression. I may provide keys to be driven behind the
locking block to force the teeth down into the grooves and to keep them securely
engaged the block being released by a screw or other means.
The locking block may work vertically or in an inclined direction.
Dated this 17th day of March 1891.
CARPMAEL & Co.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Gun Mountings.
J, 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 :—
This invention relates more especially to the mounting of quick firing guns
where the gun is carried in a cradle having trunnions which are received into
bearings upon a shield or support capable of turning to admit of the gun being
trained upon the target.
In such and in other cases it is frequently required that the gun should be
capable of being readily mounted and dismounted, so that it may be stowed away
conveniently when out of use and when required may be again mounted ready for
service without loss of time.
For these purposes I secure the trunnion bearings to the shield or other support
in the following manner: The support is recessed to receive the bearing which
slides into its place in an horizontal direction from rear to front. The support is
so formed as to confine the bearing so that it cannot escape from its place laterally.
Projecting forward from the bearing near the bottom there is a Jug which fits
into a corresponding recess in the support and at the back of the bearing there is
a heel projecting downwards. This heel is made of a hook like form and engages
with the rear end of the support.
When the bearing is in position it is locked by placing behind it a block having
transverse teeth on its underside which enter corresponding grooves formed in the
support in rear of the bearing. A screw locking bolt passes down through the
block and enters a corresponding screw threaded hole in the support. The screw
threads may be cut away in segments so that a part of a turn only is required to
lock and to release. The screw is secured to the block by means of a garter
groove and keys In the head of the screw there is a socket to receive a lever by
which to turn it. In order to lift the screw locking bolt when the threads are
disengaged, a stem with rack teeth upon it is provided upon its head, with this a
toothed arc engages.
An arm projecting rearwards from the bearing carries the
axis of the arc and on this axis there is a hand lever-means are also provided for
firmly clamping this lever in position.
I
To force the bearing home to its place upon the support 1 joint to the latter a
strap carrying a screw which if need be can be applied behind the bearing. A
few turns of this screw thrusts the bearing forward to the full extent.
By these means the gun and mechanism can be very rapidly placed in position
on the support and the bearings fixed with that solidity which is essential and
they can be removed with equal facility. All the parts required for fixing the
bearings are secured to them so that they cannot be carried away or mislaid.
Figure 1 is a side elevation of a portion of a gun mounting such as above
described,

page_text: Figure 2 is a plan of the same.
a is a portion of the support, it can pivot about a vertical axis but has no other
freedom. b is a portion of the armour plate shield securely fixed to the support;
in Figure 1 the part 6 is omitted. c is a portion of the cradle in which the gun
can slide. d is part of the gun. e is the piece in which the bearing is formed;
the trunnion of the cradle is received into it. e is a lug projecting forwards from
the lower part of the bearing and lodged in a corresponding recess in the part a.
is. a heel at the rear of the bearing entering a notch of like form at the back
of the support a. f is a locking block, it has teeth f1 on its under side entering
corresponding grooves in the support. 9 is a screw which fixes the locking block
in its place; a hole is tapped in the part a to receive it. The screw threads on the
screw and within the tapped hole are in part removed so that a part of a turn
suffices to release the screw so that it may be lifted out of its hole. Figure 3 is a
transverse section of this screw. is a garter groove in the screw which receives
a pin connecting the screw with the block. is a socket in the head of the screw
to receive a lever for turning it; this part is so formed that it can only be turned
through the proper angle, it then comes to abut upon the bearing e. h is a lever
with gear teeth upon it; this lever is mounted in a fork formed in the horn e³ at
the rear part of the bearing. The lever engages with teeth on the stem of
the screw g and by means of this lever the screw can be lifted. " is a lever fixed
upon the pivot pin of the lever h, this pin is threaded and screws in the forked
horn &¹.
When the lever i is moved rearwards the two sides of the fork are drawn together
and the lever his clamped fast. 1 is a hole to receive a pin to retain the screw g
in either of its positions. is a projection upon the bearing behind which a screw
may be applied if necessary to force the bearing home, the jointed strap which
carries the screw is shewn in dotted lines in Figure 1.
Sometimes in place of arranging the toothed locking block behind the bearing
I fit it into a recess therein and I so arrange that the locking block may be raised
up into the recess to disengage the teeth and lowered down to make them enter
the grooves in the support. The block for this purpose is provided with a screw
stem projecting upwards. There is a nut upon the screw stem and this is held in
a piece of dovetail or other form fitted into a corresponding groove in the upper
surface of the bearing in rear of the trunnion-or the piece may be otherwise
attached to the bearing.
The nut has a flange upon its under side and the dovetail piece is recessed on its
under side to receive the flange. The nut is thus prevented from moving end wise
but is able to turn freely. At its upper end the uut has a head keyed upon it in
which are recesses to receive a lever for turning the nut; or for this purpose a
ratchet lever may be provided. Between the flange of the nut and the recessed
surface of the dovetail piece are a pair of spring washers tending to keep the locking
block down on its seat in case the trunnion bearings lift in consequence of any small
vertical play particularly when the gun is fired at depression.
Figure is a side elevation of part of a gun mounting in which as above
described a recess is provided in the bearing to receive the locking block. Figure 5
is a half plan and Figure 6 is a rear elevation partly in section of some of the
parts.
The
As before a is the support and the shield; in Figure 4 the shield is not
represented. c is the cradle, d is the gun, e is the bearing in which the cradle
trunnion is held and is the locking block. At e and e' the bearing engages with
the support substantially as is shewn in the previous figures but the position of the
locking block is changed and it now is lodged in a recess in the bearing e.
locking block is provided with a stem on the upper part of which is a screw thread.
kis a nut upon the stem f; the nut is flanged around its base and it is held so that it
is free to turn in the piece which is dovetailed into the top of the bearing e. There
are spring washers at m which bear upon the upper side of the flange of the nut
and upon the top of the recess in the dovetailed piece ; these spring washers

page_text: become compressed when by turning the nut the locking block is forced down and
they ensure under all circumstances a downward pressure of the teeth into the
notches in the support a.
The dotted lines n in Figure 4 show a ratchet spanner
applied to the nut k for the purpose of turning it; this spanner may remain con-
stantly upon the nut. o is a locking pin to secure the spanner when it is out of use.
The shield is notched at b¹ to allow the spanner to move through a larger angle.
The stem of the locking block has a stud f projecting from it as is more clearly
seen in Figure 7. The stud f is lodged in an inclined groove in a bolt p which
works in a transverse horizontal passage through the bearing e. When the locking
block is raised the bolt p shoots out from the side of the bearing into a recess c¹ in the
side of the cradle as is seen in Figure 8. By this arrangement the unlocking of the
bearing is prevented when the gun has not previously been brought to a horizontal
position, it being inconvenient that it should be dismounted when in any other
position. is a small axis with a pointer q' upon it at its hinder end and at its fore
end it is provided with a crank pin which engages in a recess in the bolt p so that
the movement of the bolt turns the axis; the indicating finger y' thus shows at all
times whether the bearing is locked or free.
The projection e' upon the bearing (behind which a screw may be applied as
previously described) is arranged at such a height above the top of the screw
stem that the lever n cannot be shipped or unshipped unless the block f is
driven home.
I may provide keys to be driven behind the locking block to force the teeth down
into the grooves and to keep them securely engaged-the block being released by a
screw or other means.
The locking block may work vertically or in an inclined direction.
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 means herein described for securing the bearing e to the support a con-
sisting in arranging the bearing to slide into its place in the support from rear
to front and in providing the bearing with parts that then engage with corresponding
parts on the support and in preventing the return or rearward movement of the
bearing by a locking block with teeth on its underside which enter corresponding
recesses in the support.
2. Gun mountings in which the bearing is connected with and locked in
position upon the support substantially as described and represented by the annexed
drawings.
Dated this 16th day of December 1891.