IMPROVE- MENTS IN HYDRAULIC COAL TIPS AND IN HYDRAULIC APPARATUS SUITABLE FOR WORKING THE SAME, AND FOR OTHER USES
Year: 1877

page_text: LETTERS PATENT to Andrew Betts Brown, Engineer, of Rose Bank Ironworks,
Edinburgh, in the County of Edinburghshire, for the Invention of "IMPROVE-
MENTS IN HYDRAULIC COAL TIPS AND IN HYDRAULIC APPARATUS SUITABLE
FOR WORKING THE SAME, AND FOR OTHER USES."
Sealed the 8th June 1877, and dated the 9th April 1877.
PROVISIONAL SPECIFICATION left by the said Andrew Betts Brown at the
Office of the Commissioners of Patents on the 9th April 1877.
ANDREW BETTS BROWN, Engineer, of Rose Bank Ironworks, Edinburgh, in the
County of Edinburghshire. "IMPROVEMENTS IN HYDRAULIC COAL TIPS AND IN
HYDRAULIC APPARATUS SUITABLE FOR WORKING THE SAME, AND FOR OTHER USES."
This Invention has for its object improvements in hydraulic coal tips and in
bydraulic apparatus suitable for working the same, and for other uses.
My Invention relates to hydraulic apparatus for tipping coals from railway
trucks at various levels down a shoot into the hold of vessels. Hitherto these
hydraulic tips have been actuated by a hydraulic cylinder sunk below the level of
the quay wall in expensive foundations, the upper structure being a heavy frame-
work resting upon stone foundations carried up from the bottom of the cylinder to
the level of the quay wall. The rising cage or truck platform and its heavy tipping
cylinder is placed on the top of the hydraulic ram, all of which gear is very heavy
and together with the railway truck weighs nearly ten tons while the contents of
the truck weigh but six tons. In some cases the ram and cage have been partially
balanced, but this is possible only to a small extent.
The object of my Invention is to construct a hydraulic coal tipping apparatus
which shall dispense with all foundations of any importance beneath the level of
the quay wall, and also to entirely balance the ram and cage and also in great part
the railway truck.
My improvement in the hydraulic apparatus consists of an improved automatic
cut-off gear applied to the top of the steam accumulator, which also serves as a
governor of the speed of the engines and a stop apparatus in the event of a burst
pipe or the accumulator running down. The suction and delivery valves also of
the pump are constructed under my Invention of an improved frictionless form.

page_text: In constructing hydraulic tipping apparatus I erect by the side of the quay a
strong iron framing with four inverted hydraulic cylinders, two on each side. Two
of these cylinders are lifting cylinders and the other two are tipping cylinders;
the lifting cylinders are placed in the centre of the framing part of which they
form. Immediately behind them on the land side of the quay are placed two
similar inverted cylinders, which are for the purpose of tipping the cradle. The
rams of all cylinders work downwards, and are mado solid to act partially as
counterweights to the cage and truck; as this is not sufficient, however, I apply
a pile of cast-iron counterweights hung from the ram cross heads. These weights
work between wrought-iron legs, which support the inverted cylinders. Upon the
inner sides of the lifting cylinders iron guides are formed, upon which the cage is
guided; cach lifting ram carries a pulley, while another pulley is mounted on the
top of the cylinder. The chain passes from a fastening on the inside round the
lifting rain, over the pulley at the top and down the inside of the frame, laying
hold of the lifting cage. In like manner the tipping rams have a similar arrange-
ment, the chains however laying hold of the hinged rails upon which the truck
stands. These cylinders are all of a double-acting description, bored throughout,
and pistons are formed on the ends of the rams. The object of this is that while
the dead or useless weight is counterbalanced up, excepting the preponderance
necessary to allow the truck when empty to descend by gravity, the counterbalance
may be blocked up when the truck is being rolled off the cage by water imprisoned
in the annular space of the cylinder, otherwise the cage would run up of its own
accord.
Similarly, the tipping rams are counterweighted to partially tip the truck when
full of coals. The front of the framework next the quay is constructed in the usual
manner, with a rack on each side, upon which the shoot rests. The shoot is raised
by the action of the cradle in lifting, and is suspended when raised to the height
required by a chain running over pulleys on the top of the framing and inade fast
in the ordinary way.
The action of this apparatus is as follows:-When the truck of coals is placed
upon the cage water is admitted to both sides of the pistons in the hydraulic lifting
cylinders, and acting upon the ram raises the load, the ram and balance weights
descending. The tipping rams descend by their own gravity as the cage rises, and
they suck in water through a suction valve communicating with the exhaust or
return main. When the necessary height has been reached at which to tip the
truck the lifting valve is closed, while pressure water is admitted to the tipping
ram when the cage and truck aro lifted at their rear end sufficiently to cause the
coals to run down the shoot. By exhausting the water from the tipping cylinders
the empty truck and platform return to their level position, the empty truck being
unbalanced to an extent sufficient to cause it to descend. The lifting valve is then
closed which, imprisoning the water in the annular space, retains the balance weights,
and allows the truck to be run off the cage, and in the same manner water
imprisoned in the tipping cylinder holds the rails from rising.
When it is necessary to raise the shoot to a different height the water is
exhausted from the annular space, when the balance weights will carry the shoot
up to the requisite height. It is then necessary to admit water to the annular
space to haul down the cage by lifting the balance weights.
My improvements in connection with the accumulator from which water under
pressure is supplied to the cylinders are as follows:-To the top of the steam
accumulator cylinder I apply a stuffing box, through which a rod works which
projects sufficiently far into the cylinder to come in contact with the steam piston
when it has been pumped up sufficiently high. On the top of this rod I place a
weight, or otherwise I cause the rod to enter the steam cylinder when the steam
piston of the 'accumulator descends; the outer end of this rod is attached by a
chain to the end of a lever connected with the rod of a slide valve. The slide valvo
rod passes through a stuffing box into a valve chest which is in connection with
the accumulator, and contains a slide valve working upon a valve face having an

page_text: admission and an exhaust port. The admission port leads to the end of a hydraulic
cylinder, having therein a small ram working through a stuffing box; to this ram
is attached a connecting rod with a screw adjustment which actuates an ordinary
steam throttle valve, controlling the passage of steam to the pumping engines. A
strong spiral spring tends to force the ram into its cylinder against the outward
thrust of the water in the cylinder.
The action of this apparatus is as follows:-When the pumping engines are set
to work by the partial opening of the throttle valve by hand, or by providing a
very small leakage, the engines will revolve until the accumulative piston and ram
begin to rise. That moment the pressure of water will rise from zero up to that
represented by the steam pressure in the accumulator, which at once oporates on
the small ram above referred to and opens the throttle valve, permitting full steam
to pass from the accumulator to the engines. When the accumulator rises to the
top of the cylinder it lifts the weight on the rod, allowing the chain passing to the
lever to slacken. The hydraulic pressure then acting upon the unbalanced valve
spindle shifts the slide valve to that position in which it exhausts the water from
the small hydraulic cylinder; the spring at once acting closes the throttle valve.
It is obvious that should the accumulator, by being overworked or by the sudden
bursting of a pipe, suddenly descend to the bottom, and thus unloading the engines,
the throttle valve will at once close and stop them.
When I use a single cylinder engine, which must not be allowed to stop but must
revolve slowly when water is not being required, I connect by a pipe to the before-
mentioned small hydraulic cylinder another hydraulic cylinder placed on the
pressure main, into which works a ram having its end turned to form a valve.
This valve, when pressure is admitted to the cylinder, will be held firmly against
the valve seat on the delivery pipe leading from the engine valves to the accumu-
lator; so long as this is closed and the throttle valve open the accumulator will
be pumped up, but directly it is full the water will be exhausted from the
hydraulic cylinder of the cut-off gear and at the same time from the cylinder on
the delivery pipe. The steam consequently will be cut off the engines and the
pressure released from the pumps.
A. bye pass steam pipe from the accumulator to engine valve chest is regulated
to drive the engine dead slow whilst the throttle valve is closed, and during this
time the water will be taken in at the suction valve of the pump and delivered
through the valve seating on the delivery pipe back to the tank; on the fall of the
accumulator piston this orifice will be closed, and the throttle valve opened at the
same operation.
Another improvement consists of forming the suction and delivery valves of the
pump of simple inverted cones, hollow internally, or of other similar form, without
any feathers to guide them in their seats. These valves are kept in a stable
position by the apex of their cone descending considerably below the seat of the
valve, and receiving into it the end of a spindle working through a guide in the
valve box cover. Between a collar on the spindle and the said cover a spring is
introduced, to keep a light pressure upon the valve but to allow it a certain amount
of play, or rock, or roll in its seat. The important object to be gained by this
arrangement is greater speed in closing and freedom from noise when at work.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Andrew Betts Brown in the Great Seal Patent Office on the 9th
October 1877.
ANDREW BETTS BROWN, Engineer, of Rose Bank Ironworks, in the County of
Edinburghshire. "IMPROVEMENTS IN HYDRAULIC COAL TIPS AND IN HYDRAULIC
APPARATUS SUITABLE FOR WORKING THE SAME, AND FOR OTHER USES."

page_text: This Invention has for its object improvements in nyaraulic coal ups and in
hydraulic apparatus suitable for working the same, and for other purposes.
The Invention relates to hydraulic apparatus for tipping coals froin railway trucks
at various levels down a shoot into the hold of vessels. Hitherto these hydraulic
tips have been actuated by a hydraulic cylinder sunk below the level of the quay
wall in expensive foundations, the upper structure being a heavy framework resting
upon stone foundations carried up from the bottom of the cylinder to the level of
the quay wall. The rising cage or truck platform and its heavy tipping cylinder
is placed on the top of the hydraulic ram, all of which gear is very heavy, and
together with the railway truck weighs nearly ten tons, while the contents of the
truck weigh but six tons. In some cases the ram and cage have been partially
balanced, but this is possible only to a small extent.
The object of my Invention is to construct a hydraulic coal tipping apparatus
which shall dispense with all foundations of any importance beneath the level of the
quay wall, and also to entirely balance the ram and cage, and also in great part the
railway truck.
My improvement in the hydraulic apparatus consists of an improved automatic
cut-off gear applied to the top of the steam accumulator, which also serves as a stop
apparatus in the event of a burst pipe or the accumulator running down. The
suction and delivery valve also of the pump are constructed under my Invention of
an improved frictionless form.
In constructing hydraulic tipping apparatus I erect by the side of the quay a
strong iron framing with four hydraulic cylinders, two on each side. Two of these
cylinders are lifting cylinders, and the other two are tipping cylinders. The lifting
cylinders are placed in the centre of the framing. Behind them on the land side of
the quay are placed two cylinders, which are for the purpose of tipping the cradle.
The rams of the lifting cylinders work downwards, and are made solid to act
partially as counterweights to the cage and truck. As this is not sufficient however,
I apply a pile of cast-iron counterweights hung from the ram cross heads. Upon
the framing on the inner sides of the lifting cylinders iron guides are formed, upon
which the cage is guided. Each lifting ram carries a pulley, while another pulley is
mounted on the top of the cylinder. The chain passes from a fastening on the
inside round the lifting ram, over the pulley at the top, and down the inside of the
frame, laying hold of the lifting cage. In like manner the chains of the tipping
rains have a similar arrangement, laying hold however of the cage and of the hinged
rails or cradle upon which the truck stands. The lifting cylinders are of a double
acting description, bored throughout, and pistons are formed on the ends of the
rains. The object of this is that while the dead or useless weight is counterbalanced
(excepting the preponderance necessary to allow the truck when empty to descend
by gravity), the counterbalance may be blocked up when the truck is being rolled
off the cage by water imprisoned in the annular space of the cylinder, otherwise the
cage would run up of its own accord.
Similarly, if thought desirable, the tipping rams may be counterweighted to
partially tip the truck when full of coals. The front of the framework next tho
quay is constructed in the usual manner with a rack upon each side, upon which
the shoot rests. The shoot may be raised by the means of the cage in descending
acting on the shoot through chains running over pulleys on the top of the
framing.
The action of this apparatus is as follows:-When tho truck of coals is placed
upon the cage, water is admitted to both sides of the pistons in the hydraulic lifting
cylinders, and acting upon the ram raises the load, the ram and balance weights
descending. When the necessary height has been reached at which to tip the truck,
the lifting valve is closed, while pressure water is admitted to the tipping ram, when
the truck is lifted at its rear end sufficiently to cause the coals to run down the
shoot. On exhausting the water from the tipping cylinders the empty truck and
cradle return to their level position. The lifting cylinders are next opened to the
exhaust on both sides of the pistons, and the cage comes down, the empty truck

page_text: being unbalanced to an extent sufficient to cause it to descend. The lifting valve is
then closed, which, imprisoning the water in the annular space, retains the balance
weights, and allows the truck to be run off the cage.
When it is necessary to raise the shoot to a different height, the cage being up,
the chains in connection with the shoot are made fast to it and water is admitted
to the annular space to haul down the cage by lifting the balance weights.
My improvements in connection with the accumulator from which water under
pressure is supplied to the cylinders are as follows:-To the top of the steam
accumulator cylinder I apply a stuffing box, through which a rod works, which
projects sufficiently far into the cylinder to come in contact with the steam piston
when it has been pumped up sufficiently high. On the top of this rod I place a
weight, or otherwise I cause the rod to enter the steam cylinder when the steam
piston of the accumulator descends. The outer end of this rod is attached by a
chain to the end of a lever connected with the rod of a slide valve. The slide
valve rod passes through a stuffing box into a valve chest, which is in connection
with the accumulator and contains a slide valve working upon a valve face having
an admission and an exhaust port. The admission port leads to the end of a
hydraulic cylinder, having therein a small ram working through a stuffing box.
To this ram is attached a connecting rod with a screw adjustment, which actuates
an ordinary steam throttle valve controlling the passage of steam to the pumping
engines. A strong spiral spring tends to force the ram into its cylinder against
the outward thrust of water in the cylinder.
The action of this apparatus is as follows:-When the pumping engines are set
to work by the partial opening of the throttle valve, by hand, or by providing a very
sinall leakage, the engines will revolve until the accumulator piston and rain begin
to risc. That moment the pressure of water will rise from zero up to that
represented by the steam pressure in the accumulator, which at once operates on the
small ram above referred to and opens the throttle valve, permitting full steam to
pass from the accumulator to the engines. When the accumulator rises to the top
of the cylinder it lifts the weight on the rod, allowing the chain passing to the
lever to slacken. The hydraulic pressure then acting upon the unbalanced valve
spindle shifts the slide valve to that position in which it exhausts the water from
the small hydraulic cylinder, the spring at once acting closes the throttle valve.
It is obvious that should the accumulator by being overworked, or by the sudden
bursting of a pipe, suddenly descends to the bottom, thus unloading the engines,
the throttle valve will at once close and stop them.
When I use a single cylinder engine, which must not be allowed to stop, but
must revolve slowly when water is not being required, I connect by a pipe to the
before-mentioned small hydraulic cylinder another hydraulic cylinder placed on the
pressure main, and in which works a ram or piston acting upon a valve fitted to
an opening in the main. This valve when pressure is admitted to the cylinder
will be held firmly against the valve seat on the delivery pipe leading from the
pump to the accumulator. So long as this is closed and the throttle valve open,
the accumulator will be pumped up, but directly it is full the water will be
exhausted from the bydraulic cylinder of the cut-off gear, and at the same time
from the cylinder on the delivery pipe. The steam consequently will be cut off the
engines and the pressure released from the pumps.
A bye pass steam pipe from the accumulator to engine valve chest is regulated
to drive the engine dead slow whilst the throttle valve is closed, and during this
time the water will be taken in at the suction valve of the pump and delivered
through the valve seating on the delivery pipe back to the tank or into the suction.
On the fall of the accumulator piston this orifice will be closed and the throttle
valve opened at the same operation.
Another improvement consists of forming the suction and delivery valves of the
pump of simple inverted cones, hollow internally, or of other similar form, without
any feathers to guide them in their seats. These valves are kept in a stable
position by the apex of their cone descending consideraly below the seat of the

page_text: valve and receiving into it the end of a spindle working through a guide in the
valve box cover. Between a collar on the spindle and the said cover a spring is
introduced to keep a light pressure upon the valve, but to allow it a certain
amount of play or rock or roll in its seat. The important object to be gained by
this arrangement is greater speed in closing and freedom from noise when at.
work.
In order that my said Invention may be most fully understood and readily
carried into effect, I will proceed to describe the Drawings hereunto annexed.
work.
In order that my said Invention may be most fully understood and readily
carried into effect, I will proceed to describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
The hydraulic coal tip is shown in Sheet No. 1, Figure 1 being a front
elevation, and Figure 2 a side elevation, showing a section of the quay wall. It.
is also shown on Sheet No. 2, this figure representing a rear elevation, partly in
section, and to a larger scale.
The coal tip is erected upon a floor-like structure of wrought iron A. The front
portion of this rests upon the quay wall at B, the remainder resting on hard
ground. The upper framework is constructed by preference of wrought iron, the front
members C, C, rest on the quay, and are each provided with diagonal bracing D, D,
(Sheet No. 2) also resting on the quay wall. The internal part of the uprights C
are fitted with a rack of the usual construction to support the coal shoot E, so as
to hold it at different elevations. On the top of these uprights a chain pulley F
is placed, over which the chain passes which supports the point of the shoot in the
ordinary manner. This front portion is quite secure in its foundations, and there-
fore requires no adjustment. The centre members of the structure G, G, form
guides for the cage H, H, to run upon, it is guided by long guides running from
I to J (Figure 2, Sheet No. 1, and Sheet No. 2). Upon these guide members the
hydraulic lifting cylinders K are placed inverted, with their rams working down-
wards. To these rams are hung a sufficient quantity of cast-iron balance
weights L to counterweight the cradle and a sufficient portion of the truck, allowing
only enough unbalanced weight to overcome the friction of the apparatus in
descending.
The cylinders K (shown in section in Sheet No. 2) are fitted with rams M of
about half their area, having at their outward extremity a pulley N. From a fixed
point on the cylinder at O, the lifting chain passes round the pulley N on the ram,
and over the pulley P on the end of the cylinder down the inside of the hoist, and
round the compensating pulleys Q, Q, on the cradle H, upwards again round the
pulley P on the other lifting cylinder, and thence by a course similar to that already
traced to the fixed point O on the other side. The cage or rising platform with its
hinged rails or cradle is shown coloured blue for better illustration. On the ends of
the ram M are pistons R, R, fitted with the usual cup leathers or other packing.
Pipe branches lead from the annular space of the cylinder at S to the branch M of
the valve gear (Sheet No. 3) to be hereafter described, and from the large bore of
the cylinder T to the branch L on the valve gear. These cylinders, balance weights,
and guide members of the structure are supported on screw jacks U, U, having the
.usual arrangement of screw and worm wheel; these jacks are placed upon girder
supports resting on the floor-like structure. In this way this portion of the
structure can be adjusted to the level of that on the front wall in case of the
.foundation subsiding. The back members are carried upon similar screw jacks
.arranged in a similar manner; the whole iron structure is cross braced, as shown
Between the guide members and the back member is placed the tipping cylinder V
(Sheet No. 1), which is shewn in the reverse direction to the lifting cylinders,
although it may be arranged and counterweighted to assist the tipping of the truck,
the same way as the lifting cylinders. For simplicity, however, it is shewn to
work upwards, which dispenses with a double-acting ram. The cylinder V is fitted
with a ram having a single pulley at its end, while on the end of the cylinder two
pulleys are arranged at W. The tipping chain lays hold of the hinged portion or

page_text: cradle of the cage at X (Figures 1 and 2), and passes over the pulley Y outside the
fraine, and around the small pulley on the end of the tipping cylinder, up inside of
the frame, round the pulley on the point of the ram, down the outside of the
cylinder, and round the large pulley W, being thereafter carried round the com-
pensating pulleys on the lower part of the cage, and on to the tipping cylinder on
the other side, in the same manner as the lifting cylinder chain. Branch pipes at
Z, Z, on the tipping rains lead to the admission port of the valve I (Sheet No. 3)
which is hereafter described.
To more clearly illustrate the arrangement of the tipping chains they are shown
in red dot lining.
Sheet No. 3 represents the arrangement of the slide valves for operating the
hoists. Figure 1 is a plan; Figure 2 is a vertical section on the line A, A, Figure 1;
Figure 3 is a vertical section on the line B, B, Figure 2; and Figure 4 is a vortical
section on the line C, C, Figure 2. The valve A communicates past the valve F
and by means of the pipe L with the lifting cylinders above the pistons, and the
valve B by means of the pipe M with the annular spaces below the pistons. The
valvo E is arranged to place the chest of valve B in communication with either tho
pressure pipes N, or exhaust pipes O, and the valve A admits pressure and exhausts
from the casing of valve F.
In the ordinary process of lifting and lowering waggons the slide valve F is placed
so as to uncover the ports leading to the tops of the lifting cylinders and remains
passive, leaving the valve A in direct coinmunication with the cylinder. The
valve F is also placed and remains passive in a position leaving the valve B below
it in direct communication with the prossure mains. The valves A and B are
worked together by means of the weigh shaft G operated from the cage by a rod
attached to the lever H. When these two valves are opened pressure is admitted
simultaneously, both above and below the pistons of the lifting rains, which are
thus forced downwards by the excessivo pressure above the pistons, or in other
words the pressure acting on the sectional area of the rams. When the waggon has
been lifted to the necessary height the valves A and B are closed, and the slide
valve I is opened by a lever P (shewn in Figure 1) and rod also worked from the
cage, admitting pressure to the tipping cylinder; this valve is of the ordinary single
ported description, similar to the valve F. The cradle with the wagon upon it is.
then tipped, and when empty is returned to a horizontal position by reversing the
valve I and exhausting the water from the tipping cylinders. The valves A and B
are then reversed, thus placing the lifting cylinders both above and below the
pistons in communication with the exhaust means O. The unbalanced weight of
the waggon then causes the cage to descend, and the annular spaces below the
pistons are filled by water drawn by suction through the clack valve J.
When the cage has descended to the quay level the empty waggon is run off, and
to prevent the cage from rising by the weight of the balance weights an inverted
slide or non-return valve K is placed in the same casing as the valve B. By incans
of this valve and the clack valve J the water is confined in the annular spaces of
the lifting cylinders, thus holding or locking the rams and keeping the cage in its
position for the reception of another loaded wagon.
When it is required to raise the point of the shoot the chains which are attached
thereto and led over pulleys at the top of the framing are made fast to the cage.
(which has been previously elevated). The valve F is then reversed and remains
passive, so as to place the top of the lifting cylinder in communication with the
exhaust mains. The valves A and B are then opened as before, but pressure can
only get into the annular spaces of the lifting cylinders, causing the rams to be
drawn in or lifted, taking with them the balance weights, and thus allowing the
entire weight of the cage to operate in lifting the shoot. If however a loaded
waggon be placed on the cage its weight will elevate the point of the shoot without
the intervention of the valve F. By reversing the valve E the casing of the valve B
is placed in communication with the exhaust mains, and no pressure is then

page_text: admitted to the annular spaces of the lifting cylinders. The full area of the pistons
instead of the sectional area of the rams is then effective, and the hoists in this way
can be worked either in double or single power. The valves are placed in a pit
outside the frame, the levers projecting inside.
A
In Sheet No. 4 the improvements in the details of governor gear and pump valves
are shewn. Figure 1 is a vertical section of a steam accumulator, with pumping
engine built upon the steam cylinder, as shewn. The engine is of the single cylinder
description, having its steam cylinder at A and pump at B. The pump is fitted
with the improved suction and delivery valves C, D, which are shewn in larger
section at Figure 2. The valve proper is shewn at D, and is without feathers,
having a spherical bearing face at E which rests upon the seat. A spindle F is
guided at its upper part in the cover guide G, the lower part of the spindle being
pointed and resting in the valve at H, which is considerably below the seat.
disc I controls the amount of roll or adjustment which the valve has, being made of
a sufficiently smaller diameter than the interior part of the valve. India-rubber or
other springs are arranged, as shewn at J, between the disc I and cover G, so that
the necessary pressure is put upon the valve. The action of this valve is com-
paratively frictionless, falling in nuch shorter time than those usually fitted with
feathers working in the seats, and thus enabling the pumping engine to work
quicker. On the top of the accumulator steam cylinder a rod K works through a
stuffing box L, having a weight M to cause it to descend when the accumulator
piston moves down. To this rod is attached a chain, which works over a pulley N,
and lays hold of the end of a lever O, which actuates a slide valve P, shewn in large
section, Figure 3. When the weight descends this valve opens the port Q, leading to a
hydraulic cylinder R, thus communicating the hydraulic pressure from the hydraulic
cylinder of the accumulator, which is conveyed by the pipe S, Figure 1. The
pressure acts upon the plunger T and upon the spring U, opening the throttle
valve V of the steam pipo leading to the pumping engine, the plunger T being con-
nected to the throttle valve rod by the lever and coupling screw W. A pipe also
leads from the port Q, as shewn at X, to the piston of a relief valve Y, which works
in the hydraulic cylinder Z, as shewn. This piston has a greater area than the
relief valve. When the port Q communicates the hydraulic pressure to the piston
it remains closed, but when the accumulator steam piston is pumped up it raises the
weight M, slacking the chain, and the unbalanced pressure acting on the spindle of
the slide valve P moves that valve into a position which causes a communication
from the cylinder R, and the release cylinder Z, with the exhaust, whereupon the
throttle valve V is instantly closed, and the relief valve Y opened. By a small
leakage in the throttle valve, or a bye-pass in the steam pipe, the engine still con-
tinues in motion with a small amount of steam, and the water passes from the relief
valve Y to the suction valve C by an escape pipe, as shown. In this way the pump
is relieved from work, and a small quantity of steam suffices to keep the pumping
engine in motion.
When water is used from the steam accumulator, however, the weight M. drops,
opening the throttle valve V and closing the relief valve Y at the same operation.
The throttle valve V will also be instantaneously closed by the spring when from
any cause, such as the breakage of a pipe, the pressure in the main hydraulic
cylinder is lost.
Having thus described the nature of my said Invention, and the manner of per-
forming the same, I would have it understood that I claim,―
First. The construction of hydraulic coal tips having the hydraulic cylinders
carried upon the guide frame or tower, and the said guide frame or tower itself
supported upon a floor-like structure laid upon the surface soil, substantially as
described.
Second. The mechanisın for raising and lowering the platform of a coal tip, con-
sisting of inverted hydraulic cylinders with rams and pistons, or their equivalents,
and counterpoises, arranged substantially as described.

page_text: Third. The mechanism for tipping the trucks, consisting of chains connected with
the lifting platform and the hinged rails, and passing around the tipping cylinder
and its rim, substantially as described.
Fourth. The construction of hydraulic coal tips, substantially as described.
Fifth. The combination with a steam engine, working a pump or pumps feeding
an accuumlator, of a valve, which is held open by the pressure in the accumulator,
and which when this pressure is removed closes, and so shuts off the supply of
steam to the engine.
Sixth. The combination of gear, substantially as described, by which the steam
is cut off from the pumping engine when the accumulator is full, as well as when
from any cause the pressure in the accumulator ceases to be maintained.
Seventh. The combination of gear, substantially as described, to be used in con-
nection with a single cylinder engine working a pump or pumps feeding an
accumulator, for the purpose of permitting the engine to remain continuously iu
motion.
Eighth. The construction of pumps with valves having spherical bearing surfaces,
and free to roll, but guided and controlled substantially as described.
In witness whereof, I, the said Andrew Betts Brown, have hereunto set my
hand and seal, this Eighth day of October, in the year of our Lord One
thousand eight hundred and seventy-seven.