Improvements in Recoil Presses for Disappearing and other Gun Mountings.
Year: 1891

page_text: Date of Application, 21st Sept., 1891-Accepted, 24th Oct., 1891
COMPLETE SPECIFICATION.
Improvements in Recoil Presses for Disappearing and other Gun
Mountings.
I, GEORGE HENRY BANISTER, of the Royal Arsenal, Woolwich, in the County
of Kent, Civil 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:-
My invention relates to recoil presses for disappearing and other gun mountings,
and is intended to improve the construction and increase the efficiency of such
presses.
My said invention relates more especially to recoil presses of the kind or class
commonly known as hydro-pneumatic, that is to say, presses in which a ram that
moves with the gun is employed to displace water or other liquid from a cylinder
during the recoil, and forces the said displaced liquid into a closed chamber con-
taining air, thereby compressing the said air and storing up energy which may be
subsequently used for restoring the gun to the firing position.
In hydro-pneumatic recoil presses as heretofore usually constructed, the air-
chamber is made separate from the recoil cylinder, and a non-return valve is placed
between the said cylinder and air chamber for the purpose of allowing the flow of
liquid into the air vessel during recoil while preventing the return of the said liquid
into the recoil cylinder. When it is desired to restore the gun to the firing position,
a bye-pass provided between the recoil cylinder and air chamber is opened by
suitable means and the compressed air then expands and forces the liquid back into
the recoil cylinder. Now this construction is objectionable for several reasons
among which may be mentioned the difficulty of keeping the non-return valve
quite tight so as to prevent leakage therethrough, and the trouble that is frequently
caused by the joints that are required between the recoil cylinder and air chamber.
My invention has for its object to dispense with the separate air chamber, and with
the necessity for valves, thereby removing the chief objections to the recoil presses
as heretofore constructed. And the said invention consists chiefly in constructing
and arranging the recoil ram to serve as the air chamber.
In the accompanying drawings I have shown how my invention may be
advantageously applied to a travelling gun carriage for siege artillery use.
Figure 1 is a side elevation of a disappearing gun and travelling siege carriage,
the gun being shown by full lines in the firing position, and by dotted lines in the
recoil position, and one of the carriage wheels being removed.
Figure 2 is a plan, and
Figure 3 is a longitudinal central section of the recoil press drawn to an enlarged
scale.
Like letters indicate corresponding parts throughout the drawings.
A, Figure 1, is one of the gun carriage brackets, B is the axle on which the
brackets are centered, and C is one of the travelling wheels. D is the gun and D¹
are its trunnions which are carried by arms or elevators E that are centered on and
capable of partial rotation about a pivot pin F mounted in the brackets A. G is
the radius rod, and H the elevating gear secured on the carriage bracket A. All
the foregoing parts may be constructed as heretofore and form no part of my
invention.
I is a hydro-pneumatic recoil press which is connected at its lower end to the
trail of the carriage by a pin Jon which it is free to turn during recoil. The
ram K of the said press is attached at its upper end by means of trunnions L to
the elevator arms E which arms on recoil take up a position as indicated in dotted
lines E, when the ram K is forced into the cylinder I.

page_text: Referring now to Figures 2 and 3 which show the construction of the recoil
press more fully, it will be seen that the said press comprises a cylindrical tube I
having a stuffing box and gland J and a ram K working through the said gland.
The said ram is made hollow, and constitutes an air chamber for storing up energy
in the recoil. On the inner end of the ram is screwed a cap a that forms a piston
head therefor, and in this said cap is formed an orifice b, through which the liquid
displaced from the cylinder I during recoil passes into the ram K. An annular
space c is left between the ram K and the inner periphery of the tube I, and more-
over the periphery of the cap a does not fit closely to the interior of the tube I for
reasons which will be hereinafter explained.
The said tube I is closed at its rear end by a cap d which carries a well-known
recoil-regulating device consisting of a tapered rod e lying in the axial line of the
tube and projecting through the orifice in the cap a, an annular space being left
between the tapered rod e and the sides of the orifice b. The said rod e is provided
at its inner end with a nut which limits the outward travel of the ram K. The
outer end of the said ram K is bifurcated as shown, to form trunnion arms K', to
each of which arms is attached a trunnion L. The said trunnions are received in
suitable bearings provided in the elevator arms E (see Figure 1). The air chamber
of the ram is closed at its upper or outer. end by a hollow screw plug 9, and com-
municating with the interior of this plug is an orifice closed by an ordinary
screw plug g. The orifices closed by these plugs permit the level of the liquid in
the ran to be ascertained. The air chamber is charged with liquid and air through
an orifice at the side thereof at g' Figure which orifice when not in use for
charging purposes is closed by an ordinary screw plug.
For preventing the return of the gun to the firing position after recoil I provide
an.automatic clutch mechanism for holding the ram in any recoiled position until the
clutch is purposely released by a lever provided for the purpose. The said clutch
mechanism comprises a system of links fitted with jamming blocks, and provided
with a releasing lever arranged as follows. hh are links situated one on each side
of the ram.
The said links are pivoted by a pin i to a pair of links ; which in turn
are attached by a pink to a collar secured on the tube f. The said links h are also
connected by a pin m to a link n which is provided with a collar or stop n¹. The
said stop in the position illustrated, bears upon a projecting rim of the collar 1.
The links jn are all fitted to turn freely about their respective pivot pins i k and m.
The link n passes through the said projecting rim and has pivoted upon it at o' a
lever o which is provided with a handle p and a cam surface q see Figure 3. A
suitable stop or rest is provided upon the cylinder I to support the lever, when
not in use, in a position in which it will be conveniently ready for operation.
Jamming blocks and t carried by the pins i and m respectively are arranged to
turn freely upon the said pins and to have contact with the ram K as shown,
bearing upon it with a slight pressure so as to offer a slight frictional resistance to
its motion.
8
°
The operation of the recoil press and its appurtenances will now be described.
The press is charged with liquid to a level above that of the cap a when the ram is
at its extreme outward limit of travel and the remaining space in the ram is charged
with compressed air. If now the gun is fired it will by its recoil rotate the
elevator arms E towards the position shown in dotted lines at E' in Figure 1 and
the said arms will force the ram K into the cylinder I. During this inward move-
ment of the ram the space between the caps a and d is diminished and the liquid
therein is forced past the cap a around its periphery into the space c the length of
which will be increasing and is also forced through the annular space between the
rode and the sides of the orifice b into the interior of the ram K further compressing
the air contained in the said interior.
The method in which the recoil-regulating device e operates is well known, but
.may be briefly described as follows. During the recoil movement of the cap or
piston head a the area of the annular space between the rod e and the sides of the
orifice 6 is continually changed by reason of the varying diameter of the said rod e,

page_text: Therefore the resistance offered to the passage of liquid through the said annular
space is varied and consequently the retarding effect upon the gun is similarly
varied.
j
When the ram has been brought to rest, the compressed air in the interior thereof
would tend to force it out of the cylinder I again, and so restore the gun to its
firing position, but upon the commencement of any such outward movement of the ram
the links will be turned about their pivot i owing to the friction of the blocks st
upon the rain. This movement will cause a wedging or jamming action of the said
blocks against the ram and inasmuch as the jamming blocks are connected through
the links and pink to the cylinder I the ram will be held and prevented from
further outward movement. Moreover by this movement the cam is brought near
to the rear face of the rim . To release the ram k from the jamming blocks st
the lever o is rotated about its pivot o¹ upon the link n and the cam surface q being
thus brought into contact with one part of the rear face of the rim during such
rotation and acting as a fulcrum, the lever draws back the link n and thereby
relieves the jamming pressure on the ram.
The ram is then free to move outward
under the action of the compressed air in the interior of the same. During such
movement the lever o must be held up to prevent a recurrence of the wedging
action.
In order that the ram K may be forced out as described, the water in the space c
must pass around the periphery of the cap a into the space in the tube I between
the caps a and d and as the orifice around the periphery of the cap a is of small
area there will be considerable resistance offered to the passage of the water there-
through so that the speed of movement of the ram and of the elevation of the gun
is limited. This arrangement will also slightly assist the recoil-regulating device e
to check the movement of the ram during the recoil of the gun. The collar or
stop n' on the link n limits the rearward movement of the links and prevents their
moving into such a position as would wedge the ram during the recoil movement.
The ram is therefore free to recoil but cannot return until the hand lever o is raised
to release the jamming blocks.
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 :-
First. A recoil press for a disappearing or other gun mounting in which the
interior of the ram is used as an air chamber for the purpose specified.
Second. In a recoil press for a disappearing or other gun mounting, a hollow
ram employed as an air-chamber and so constructed that an annular space is
provided between it and the inside of the recoil cylinder, and having a cap or
inner head which is provided with an orifice for the passage of a taper rod,
substantially as hereinbefore described and for the purposes specified.
Third. The combination, with the ram of a recoil press, of apparatus such as
herein described which allows the ram to move freely in recoil but prevents its
forward or return movement, for the purpose specified.
Fourth. The combination, with the apparatus for holding the ram in the recoiled
position, of suitable means for releasing the said ram, substantially as specified.
Fifth. The recoil press for a disappearing or other gun mounting constructed
and operating substantially as hereinbefore described with reference to the
accompanying drawings.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.