Year: 1888

page_text: I, ALFRED LONGSDON of 9 New Broad Street in the City of London, Civil Engineer
do hereby declare the nature of this invention (a communication to me from abroad
by the firm of Fried Krupp of Essen in the Empire of Germany, Cast Steel Manu-
facturers) and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
This invention refers to improvements in hydraulic brakes for ordnance whereby
the resistance to the recoil is made more uniform than heretofore the running out and
running in of tho said piece of ordnance can be effected, while the recoil can be utilized
for the storage of power.
These objects are obtained in and by the employment of a hydraulic cylinder or
cylinders as particularly hereafter described in connection with a delivery valve for the
liquid such liquid being forced through the brake-piston by the action of the recoil,
which liquid can be conducted into a waste pipe or an accumulator, or be in connection
with one or more of what are hereafter referred to as "equalizing" cylinders, the
contents of which also serve for the working of the brake. Similar results may be
obtained but without the storage of power by the employment of two hydraulic
cylinders of particular construction as hereafter described, one of which serves as an
equalizing cylinder for the other.
The invention will be best understood by describing same with reference to the
accompanying drawings.
Figure 1 is a longitudinal section through the hydraulic brake cylinder, piston rod,
brake valve, and the delivery valve connected with the cylinder.
Figure 2 is a section shewing the hydraulic brake cylinder and two equalizing
cylinders.
Figure 3 represents the combination of a brake cylinder with an equalizing
cylinder.
Figure 4 shews a similar arrangement but having an equalizing cylinder arranged
in the axis of the brake cylinder.
Figure 5 shews a counter pressure cylinder for the keeping closed of the brake valve.
Figure 6 shews a counter pressure cylinder in connection with the delivery valve.
Lie 11d.1

page_text: Figures 7, 8 and 9 shew modifications of the brake valve.
Figure 10 shews a modified arrangement of the hydraulic brake in which two
hydraulic cylinders are connected with the brake valve and provided with regulating
rods, one rod heing fastened at the larger end and the other at the smaller end, one
cylinder serving to equalize the other.
Figure 11 shows in sectional elevation an application of the invention to a piece of
ordnance where the piston moves on the recoil, and Figure 12 is a sectional elevation
of a similar piece of ordnance, but where the invention is so applied that the cylinder
moves on the recoil.
The arrangement and mode of connection of this new hydraulic brake with the gun
is effected in such manner that the carriage is firmly connected with the piston or with
the cylinder, whilst the other part of the brake, the cylinder, or the piston is fastoned
to the slide.
The recoil of the gun is by the carriage transferred to the movable part of the
brake and in fact if the cylinder is fixed works the movable piston, or if the piston
is fixed works the movable cylinder.
"
The piston rod a of the brake cylinder & shewn in Figure 1, is bored out to receive
the tubular valve e which is loaded with the spring d and in which tubular valve the
conically formed regulating rod e enters, it being fastened in the cylinder cover, the
degree of conical form of the regnlating rod being fixed according to calculations.
The seat of the tubular valve e is situnte in the body of the piston g which latter
contains an annular cavity which is in connection with the front portion of the brako
cylinder through ports h. When the gun is fired, the pressure of the fluid caused by
the recoil nets upon the inner end of the tubular valvo e and raises the same from its
seat, the piston (with the carriage) moving from the left to the right hand in the
direction of the arrow, Figure 1, the connection between the two sides of the piston
being effected as aforesaid by the lifting of the valve e; the fluid can then flow by
the passage and ports before mentioned through from the back side of the piston g
towards the front, the passage for the liquid during the recoil being decreased in
proportion to the increasing thickness of the fixed conical rod e.
By this means the pressure is kept constant during the whole of the recoil and the
strain caused upon the gun carriage and its foundation is considerably lossened. The
loading of the brake valve is so arranged as not to be greater than would correspond
with the piston pressure that is necessary to keep the gun with the carriage in firing
position on each elevation. As shown at Figure 11, upon elevation the slide is
inclined, and therefore there results a pressure in the cylinder by the weight of the
gun and carriage. This arrangement necessitates that upon giving forward motion to
the piece of ordnance and consequently upon the advance of the piston rod a out of
the cylinder the liquid passes both before and behind the piston g of the brake
cylinder by the passages o and p, whereby the area of the piston rod serves as working
surface. The valve c is kept closed by the spring d. The passages o and p are in
connection by a slide valve and the connection is open upon the operation of running
out. Upon running in, water under pressure onters at o, and p is connected by the
slide valve with the waste pipe; upon running out, water under pressure enters at o
and p.
Upon the running in of the piece of ordnance the liquid under pressure is admitted
before the pistong whilst the back portion of the cylinder bis connected with the
exit, the piston g being thereby drawn back and tho valve e forced upon its sent by
the working pressure. The working surface consists of the annular area of the piston.
The water flowing through the piston y will, upon firing, on account of the entranco
of the piston rod a into the cylinder b, be partly pressed out of the same corresponding
with the volume of the ingoing piston rod a.
The front of the brake cylinder is therefore connected with the delivery valve B
which serves to allow the water during the recoil, froo oxit from the front side of the
brake piston y and to keep closed the waste under ordinary circumstances.
The delivery valve B is a kind of ordinary safety valve consisting of the valve
chamber and the valve m loaded by a spring n.

page_text: The amount of loading corresponds to the working pressure in the pressure pipes.
Upon firing, the valve m is opened by the water forced from the front parts of the
cylinder. At the end of the recoil it is closed by the spring n, and also remains closed
during the operations of running in and running out.
The entrance or exit of water upon running in and running out is effected by tubular
connections o and p and the exit of the liquid forced out by the recoil passes by the
passage 9. The water flows from the delivery valve 9 either into the waste pipe, or
if an accumulation of power during the recoil is intended, into an accumulator.
In the arrangement as shown at Figure 2 the cylinder is inovable with the
carriage, as shown at Figure 12, upon a fixed frame from the right towards the left
in the direction of the arrow, Fig. 2.
The water which is forced out of the cylinder upon firing is, in the arrangement
shewn at Figure 2 taken up by the two equalizing cylinders the volume of the
piston rods of these latter being together equal to the volume of the brake piston rod.
The brake cylinder works in a similar manner to that hereinbefore described
excepting however that there is no expulsion of liquid, the voluine of the piston rod
entering the brake cylinder & being equal to that of those coming out of the equalizing
cylinders s². The entrance and exit of water upon running in and running out of the
piece of ordnance takes place in this arrangement by means of the fixed piston
rods of the equalizing cylinders whilst in the reversed arrangement with movable
piston rod the liquid passes through the connections o and p of the cylinder. In both
cases the fixed conically shaped regulating rod enters the brake cylinder on the recoil
taking place and the area of the passage for the water in the piston is contracted in
propertion to the increasing thickness of the regulating rod. From the drawing it
will be seen that the volume of liquid before the equalizing pistons is also applicable
to working and increasing the effectiveness of the brake.
Instead of two equalizing cylinders with one brake cylinder there may be one
equalizing cylinder with two brake cylinders in connection, as the brake in Figure 1
may be applied with one or two cylinders. Or instead of two equalizing cylinders
one of such may be employed in connection with a brake cylinder of "which the
diameter of the piston rod is the same as that of the brake piston rod. This arrange-
ment is shewn at Figure 3 in which the cylinders lie by the side of each other, whilst
those in the representation given in Figure 4, lie in the same axis.
In the arrangement shewn at Figures 3 and 4 the piston moves with the carriage,
the cylinder being fixed. The movement during the recoil on firing is in the direction
from left to right as indicated by the arrow.
As upon the employment of these equalizing cylinders the front and rear working
surfaces are equal, the area of the piston rod cannot be used as working surface as in
the first arrangement. It is therefore necessary to prevent the brake piston valve
from opening by the pressure upon the forward movement of the piston. This may
be effected by loading the valve corresponding to the working pressure or by a special
counter pressure cylinder which loads the valve during the forward movement of the
piston. In Figure 5 an arrangement of this counter pressure cylinder is shewn.
The hollow piston rod a is provided with a tubular valve c and carries on its shaft
a piston which is in a cylinder situated at the piston rod head, this piston is
movable with the valve, and at the end u³ projecting out of this cylinder is a spring d³.
Atv is a pipe connection for the pressure liquid behind the piston which enters
immediately if the slide valve for the forward movement of the gun is opened, and by
this means as the piston K, after deducting the area of the rod, is of greater area than
the pressure surface of the valve e, the said valve is kept closed.
When the gun and the slide valve serving for the movement of the same is in
firing position, the entrance of the pressure liquid to the brake cylinder is shut off and
at the same time the waste from is effected so that the valve is only loaded with the
spring ds, which only offers a very slight resistance to the opening of the piston valve
at the commencement of the recoil. This counter pressure cylinder can also be
applied when required in connection with the delivery valve represented in Figure 1,
when it is intended as above to diminish as much as possible the initial pressure in

page_text: the brake cylinder (Figure 6). If there is no pressure in the counter pressure cylinder
the valve is kept on its seat only by the spring which acts with less fond on the valve
than the piston of the counter pressure cylinder when under pressure.
Instead of the tubular valve shown at Figure 1, valves as shown in the arrangement
Figures 7 and 8 may also be employed these latter being circular valves c,, the
springs being outside the piston; or instead of one circular valve, several singlo
valves arranged round the piston roil may be employed, or a circular valve having
several rings arranged concentrically may also be employed.
In like manner the tube valve according to Figure 1 may, instead of a spring lying
in the piston rod be combined with a spring outside the piston rod necording to the
arrangement shewn at Figure 5.
If the purpose should be to use the brake piston rod for strain instead of for
pressure, a modification of the brake valve in accordance with Figure 9 is introduced.
The piston rod a receives into its bore the regulating rol which at the thin ond is
fastened into the cylinder cover and the piston y" is provided with a valve c³ the spring
of which d³ is held by a cover w
A brake cylinder provided with a valve constructed in the latter manner may in the
described mode be also combined with one or more equalizing cylinders or may be
employed in connection with a second bruke cylinder as shown at Figure 10. In
the arrangement shewn at Figure 10, the piston rods are movable with the carriage in
the direction of the arrow from right to left. In this arrangement the piston valvo of
the cylinder is opened from the piston side of the cylinder, and the piston valvo
of the cylinder & 1. is opened from the piston rod side of its cylinder ¹
1; the
regulating rod is fastened at the larger end and the regulating rod }, at the
smaller end, and the valve springs are sufficiently strong to prevent the opening of
the valves by the liquid upon the operation of moving the gun forwards and back-
wards. The entrance or exit of water takes place by means of tubular connections to
the fixed cylinders whilst the same effect would follow to movable cylinders and fixed
piston rods through the latter.
The specified invention can be applied to ordnance of various calibres and systoms.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed I declare that
I am aware that it lias been proposed to employ conically shaped rods, or rails of
varying diameter, in hydraulic brake apparatus, for controlling the recoil of ordnance,
such devices aro described in the patent specifications by Moncrieff and Anderson
No. 82417, by Vavasseur No. 161388, by Anderson No. 15649, also by Vavassour
No. 527.
Lam also aware that it was not new at the date of my application for patent to
employ a hollow piston rod carrying a loaded valve, as such is shown and described
in the specification of Anderson's patent beforu referred to, No. 15649, neither is it
novel to connect both sides of the cylinder, as this was described by Vavasseur in the
specification of his patent dated 27 August 1877 No. 3253 page 2 lines 20 to 29; and
Anderson by his patent No. 15649 loaded the valve by a spring.
I am also aware that the apparatus or device consisting of the hollow piston rod
and taper har and various arrangements or combinations including the same, are also
described and shown in the specifications of Letters Patent granted to Mossrs. Christio,
Gledhill and Carington, and dated 27th June A.D. 1887 No. 9125, and 29th June
A.D. 1887 No. 9217. I am also aware that the combination of the brake cylinder or
cylinders with the compensating cylinders or cylinder is described in the specification
of Letters Patent granted to the said Messrs. Christio, Gledhill and Carington and
dated 9th July A.D. 1887 No. 9688.
And I wish it understood that I do not claim in respect of these features anything
that cannot be distinguished or "differentiated" from tho inventious set forth in the
said specifications; but what I claim is :-
First. In hydraulic brakes for ordnance, tho construction and arra. go:nent of tho
olongated tubular valve c, in tho hollow piston rod a, connecting both sides of

page_text: the brake cylinder b, being loaded by a spring d, and receiving a rod e of varying
diameter, as described and shewn with reference to Figure 1 of the accompanying
drawings.
Second. In hydraulic brakes for ordnance a valve situated in the piston for
connecting both sides of the brake cylinder 6 and loaded by a spring d³, in com-
bination with a counter pressure cylinder, containing piston, on the valve
spindle, u, all constructed and acting as described and shewn with reference to
Figure 5 of the accompanying drawings.
Third. In hydraulic brakes for ordnance, the combination with the delivery valve B,
of the counter pressure cylinder as shewn at Figure 6, such delivery valve B,
consisting of, the chamber 7, exit q, and passage o, valve and spindle m³, spring nº,
piston k, cylinder and port or passage v, as particularly described and illustrated
with reference to Figures 1 and 6.
Fourth. In hydraulic brakes for ordnance, the construction and arrangement of
elongated tubular valvo contained in the brake piston g, and in the rod a, and
receiving a rod of varying diameter, together with the counter pressure cylinder 75
containing piston k³, on valve extension rod us, is, with loading spring d, in com-
bination with the spring loaded delivery valvo B, also provided, with counter pressure
cylinder and piston, shewn and described at Figure 6, as and for the purposes herein
set forth.
Dated tins 20th day of the 100.
Witness,
E. G. BREWER,
33, Chancery Lane, London.
ALFRED LONGSDON.