Improvements in Mountings and Carriages for Disappearing Guns.
Year: 1890

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COMPLETE SPECIFICATION.
Improvements in Mountings and Carriages for Disappearing Guns.
I, THOMAS ENGLISH of Hawley near Dartford. 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 the construction of mountings and carriages for disappearing
guns, my improvements being applicable either to the mounting of a heavy gun in
position, or to the carriage of a siege gun moveable from place to place on wheels, as
I shall describe referring to the accompanying drawings. Fig. 1 is a side elevation
(with one wheel removed) and Fig. 2 is a plan (with gun removed) of a carriage
according to my invention for a disappearing siege gun. Fig. 3 is a sectional plan
to an enlarged scale of the hydropneumatic air vessel. The gun A is mounted to
slide on a cradle c, and a plunger p attached to the gun works through packing in a
hydraulic recoil cylinder 6 fixed on the rear part of the cradle c. The front end of
the cradle c and the upper ends of a pair of elevator arms e are pivotted on a cross-
headh from which a tubular plunger extends at an inclination downwards through
packing into a hydropneumatic cylinder d. A pair of radius rods connect the
crosshead h to the upper ends of a pair of elevator arms e¹. Both the arms e and e¹
are pivotted on the trail brackets k, the part k¹ of each of which between the pivots
of e and e¹ is equal and parallel to the radius rods, while the arms e and e¹ are them-
selves equal and parallel, so that the stationary base k¹ and the moveable arms e and e¹
and radius rods z constitute the sides of a parallelogram, and the gun A supported
on these, as it is caused to move backwards by recoil, descends in a circular path
always parallel to itself. The pivots of the radius rods and of the arms are
formed on a cross shaft u which can be turned by a hand wheel. This cross shaft by
bevil gear g
works two elevating screws which turn in nuts swivelled to the rear
end of the cradle c. By means of these screws the cradle and the gun which it carries
are set at any desired elevation.
The hydropneumatic cylinder d which is charged with liquid communicates through
a check valve o with the lower part of the air chamber a which is made of cylindrical
form in two parts connected by flanges f bolted together having between them
hydraulic leathers set back to back. A hollow plungers open at its upper end
and fitting the leathers is enclosed within the air chamber in which it can move up
or down, always separating the liquid in the lower part of the chamber from the
compressed air in the upper part a. Should any of the air or liquid leak past either
of the leathers it will escape to the outer air.
A little liquid is admitted to the upper part a for lubrication of the upper
leather; should any of this liquid find its way into the interior of the plunger, it
will be forced out again by the pipe s¹ when the air within the plunger expands.
The
The lower part of the air vessel communicates with the cylinder d by a bye pass
screw valve which can be opened or closed by turning. a. band wheel n.
trunnions of the crosshead h are made hollow to form a communication between the
tubular plunger and pipes q leading to a throttled opening at the rear end of
the recoil cylinder b. The hydropneumatic cylinder d with its air chamber a is
pivotted by trunnions to the rear end of the trail brackets k which end rests on
the platform. The front parts of the trail brackets are supported on the axletree m
of the wheels w. Vertically below the axletree m is a shoe which is tied to the trail
brackets by ties y y' and which can turn on a holdfast as a pivot on which the
carriage and gun can be trained in any direction.
A pair of guide bars i extend downwards on each side of and parallel to the plunger r
from points in the elevator arms e¹ and slide through guides at the upper part of the

page_text: cylinder d, these guide bars serving to relieve the plunger and its stuffing box from
lateral strain.
When the gun has been raised and advanced to the firing position shewn in
Fig. 1, the by-pass valve n being closed it is retained in that position by the
pressure of the liquid in the hydropneumatic cylinder d acting on the plunger,
and also by the pressure in the recoil cylinder which communicates with d through
the pipes and the hollow plunger r. On the gun being fired it recoils, sliding
back along the cradle c in opposition to the pressure in 6 and also moving backwards
and downwards in a circular path forcing liquid out of the cylinder d past the check
valve o into the air chamber a in which it raises the plungers farther compressing
the air in and above the plunger. As the valve o closes against return of liquid to
the cylinder d, the gun remains in its back position and can be charged or other-
wise dealt with, sheltered by the parapet. When it is desired to raise the gun to
firing position the by-pass valve n is opened and the liquid forced back into the
cylinder d and also into the cylinder 6 by the pressure, of the air in a, drives out
the plunger and also the plunger of b raising and advancing the gun to the firing
position.
7"
Although I bave shewn and described a carriage mounted on wheels for a siege
gun, a similar arrangement of mounting and of the recoil and hydropneumatic
cylinder and air vessel is applicable to a heavy gun in position, by substituting for
the trail brackets ka suitable triangular carriage or framing which can turn on a
pivot and is supported by rollers running on circular rails or racers.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is:-
:-
1. For the mounting of a disappearing gun, the combination of the elevator
arms e e' the part 1 of the carriage or frame to which they are pivotted, and the
radius rods z forming a parallelogram the one upper angle of which supports elevating
screws for the rear of the cradle carrying the gun, and the other upper angle supports
the front of the cradle c and is jointed to the plunger of a hydropneumatic recoil
cylinder d, substantially as described.
2. In combination with the plunger above referred to, the guide bars i sliding
through guides on the hydropneumatic cylinder and jointed to the rear elevator arms e¹,
substantially as and for the purpose set forth.
3. The combination of the recoil cylinder b on the cradle c above referred to with
the pipes and the tubular plunger r forming communication with the cylinder d,
substantially as described.
4. Fitting the compressed air vessel for the hydropneumatic cylinder of a disappear-
ing gun with a plunger working within the vessel, so as to separate the liquid from
the compressed air, substantially as described.
Dated this 28th day of March 1890
.
ABEL & IMRAY,
Agents for the Applicant.