IMPROVEMENTS IN PUMPING ENGINES
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by the said Henry Davey at the Office
of the Commissioners of Patents on the 5th September 1883.
HENRY DAVEY of Leeds in the county of York "IMPROVEMENTS IN PUMPING
ENGINES
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One part of my present invention has reference to an improved construction of
vertical pumping engines, whereby these are enabled to be erected at the side of a
shaft or pit, while the end of the beam thereof projects over the side of the pit, so
as to leave the greater part of the pit free for the raising and lowering gear. For
this purpose, the piston rod of the inverted steam cylinder is connected to one end
of a sway beam that is pivotted to the engine beam at an intermediate point of its
length, and has its other end pivotted to a radius rod hinged to a fixed fulcrum.
The piston rod thus imparts the requisite up and down motion to the engine beam
through the sway beam, while the sway beam and radius rod constitute a parallel
motion for guiding it in a rectilineal path. By this arrangement, the cylinder can
be placed only a short distance over the engine beam, the connexion of the piston
rod with the sway beam being made to work up and down at the side of the engine
beam, or between the flitches of a double beam.
When vertical compound engines are arranged to work according to this
invention, the high pressure cylinder is by preference placed on one side of the
fulcrum of the double ended engine beam, and the low pressure cylinder on the
other side, each piston rod being connected to a sway beam as described. The
engine can, in this case, be conveniently placed between two pits, so that the one
end of the beam overhangs the one pit, and the other end, the other pit, thus
enabling the one engine to work pumps in both pits.
Another improvement relates to the construction of valve gear for actuating the
steam and exhaust lift valves of pumping engines, either such as above described;
or those of horizontal construction. It is essential in pumping engines to be able
to vary the cut-off without altering the time of opening the valves to steam. . For

page_text: this purpose, I provide, firstly, a shaft which receives a rocking motion from the
differential gear of the engine, that is to say, from a beam whose one end is moved
by the combined action of a subsidiary steam cylinder and cataract, while its other
end receives motion from the engine pistons; secondly, I provide a second shaft
which receives a rocking motion from the motion of the engine pistons alone. On
the first named shaft are fixed levers for actuating the steam valves, but instead of
being made to actuate the valves directly, they have pivotted to them other lovers
that actuate the valves, and that are connected to arms on the second above named
sliaft, that receives motion from the engine pistons.
By this arrangement, as the lever on the first shaft, having differential motion,
will be about the middle of its stroke at the commencement of the stroke of the
engine pistons, while the second shaft will be at the commencement of its motion
at that time and will be moving very slowly, the resultant motion of the pivotted
lever connected thereto will be such as always to lift the steam valve at the
commencement of the stroke of the engine piston, but to allow it to close at a point
of the stroke which may be varied by varying the angle through which the second
shaft rocks during the stroke of the main piston, such variations being obtained by
altering the point of connexion of the rod and lever by which the to and fro
motion is imparted to the second shaft. In applying this arrangement of valve
gear to the vertical construction of compound engines above described, the lover
on the first shaft receiving differential motion is made double ended and has a
second lever, such as above described, pivotted to each end thereof, the one such
lever being made to actuate the steam valve at one end of the high pressure
cylinder, and the other being made to actuate the steam valve at its other end;
and, in like manner, the valves of the low pressure cylinder are worked.
Both these levers are actuated by the second shaft that receives rocking motion
from the engine piston. In applying the said valve gear to horizontal compound
pumping engines in which the high and low pressure engines are in line with each
other, I, according to one arrangement, place the steam valves to the front ends of
both cylinders on one side of the axial line of the engine; and the steam valves to
the back ends on the opposite side of the axial line, the exhaust valves being
arranged in precisely the same manner, and the passages by which the steam and
exhaust valves at each end of the cylinder are made to communicate with each
other, being made to cross over from one side of the axial line to the other, while
the passage of the exhaust valves of the high pressure cylinder is made to
communicate with the passage of the steam valves to the low pressure cylinder.
By placing the first and second shafts of the valve gear above referred to in the
said axial line, I am enabled to work all the valves on each side correctly therefrom,
that is to say, on the one side of the first shaft are, firstly, levers with their
pivotted second levers for actuating the steam valves at the front ends of the two
cylinders, and secondly, there are levers actuating the exhaust valves to the rear
ends of the cylinders directly with differential motion; on the other side of the
shaft are, firstly, lovers with their pivotted second levers for actuating the steain
valves at the rear ends of the two stoam cylinders, and secondly, there are levers
actuating actuating the exhaust valves to the front ends of the cylinder directly
with differential notion.
According to another arrangement of such last described engines, I place all the
steam and exhaust valves in line with each other, the two steam valves. to the high
prossure cylinder being placed inside, and the two exhaust valves outside, while
the two steam valves of the low pressure cylinder are placed outside, and the two
exhaust valves inside. The steam valves of the high pressure cylinder are then
connected by ono pipe or passage, the exhaust valves of the low pressure cylinder.
by another pipe or passage, and the two exhaust valves of the high pressure
cylinder with the steam valves of the low pressure cylinder by a third pipe or
passage.
In this arrangement, the stem of each valve has a double ended lover pivotted to
ſt. The one end of this lover is actuated by a lover or tappet on a rocking shaft

page_text: receiving motion from the motion of the engine pistons, while the other end is
actuated by a tappet on a rocking shaft receiving a simple motion (i.e., not
differential) from a subsidiary steam cylinder and cataract. The tappets on the
two shafts are arranged at opposite angles for the levers of the consecutive stean
valves, so that, while the motion in the one direction effects the lifting of the one
valve, the motion in the opposite direction effects the lifting of the next valve.
The shaft which moves in accord with the engine pistons is connected by a
slotted link with a lever on the shaft actuated by the subsidiary steam cylinder
and cataract, so that while the opening of the valve to steam is, by this connection,
always made to take place at the same time, the period of cut off can be varied, as
in the previously described arrangements..

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Davey in the Patent Office on the 5th March 1884.
HENRY DAVEY of Leeds in the County of York "IMPROVEMENTS IN PUMPING
ENGINES"
One part of my present invention has reference to an improved construction of
vertical pumping engines whereby these are enabled to be erected at the side of a
shaft or pit, while the end of the beam thereof projects over the side of the pit, so
as to leave the greater part of the pit free for the raising and lowering gear. For
this purpose, the piston rod of the inverted steam cylinder is connected to one end
of a sway beam that is pivotted to the engine beam at an intermediate point of its
length, and has its other end pivotted to a radius rod hinged to a fixed fulcrum.
The piston rod thus imparts the requisite up and down motion to the engine beam
through the sway beam, while the sway beam and radius rod constitute a parallel
notion for guiding it in a rectilineal path. By this arrangement the cylinder can
be placed only a short distance over the engine beam, the connection of the piston
rod with the sway beam being made to work up and down at the side of the engine
beam or between the flitches of a double beam.
When vertical compound engines are arranged to work according to this
invention, the high pressure cylinder is by preference placed on one side of the
fulcrum of a double ended engine beam, and the low pressure cylinder on the
other side, each piston rod being connected to a sway beam as described. The
engine can in this case be conveniently placed between two pits, so that the one
end of the beam overlangs the one pit and the other end the other pit, thus enabling
the one engine to work pumps in both pits.
Fig. 1 of the accompanying drawings shews this arrangement for a compound
engine having the low and high pressure cylinders A and B placed in an inverted
position over the space between the two pits, and working the beam Q by the
connections shewn which constitute parallel inotions for the piston rods.
Another improvement relates to the construction of valve gear for actuating the
stoam.and exhaust lift valves of pumping engines, either such, as above described
or those of horizontal construction. It is essential in pumping engines to be able
to vary the cut off without altering the time of opening the valves to steam. For
this purpose, I provide firstly a shaft which receives a rocking motion from the
differential gear of the engine, that is to say, from a beam whose one end is moved
by the combined action of a subsidiary steam cylinder and cataract, while its other
end receives motion from the engine pistons; secondly, I provide a second shaft:
which receives a rocking motion from the motion of the engine pistons alone. On
the first named shaft are fixed levors for actuating the steam valves, but instead of
being made to actuate the valves directly, they have pivotted to them other levers
that actuate the valves and that are connected to arms on the second above named
shaft that receives motion from the engine pistons. By this arrangement, as the
lover on the first shaft, having differential motion, will be about the middle of its
stroke at the commencement of the stroke of the engine pistons, while the second
shaft will be at the commencement of its motion at that time and will be moving
very slowly, the resultant motion of the pivotted lever connected thereto will be
such as always to lift the steam valve at the commencement of the stroke of the
engine piston, but to allow it to close at a point of the stroke which may be
varied by varying the angle through which the second shaft rocks during the
stroke of the main piston, such variations being obtained by altering the point of
connection of the rod and lever by which the to and fro motion is imparted to
the second shaft,

page_text: Fig. 2 shews the connections. for working the two rocking shafts above
mentioned. A rod R connected to the engine piston so as to move in time with it
but with a reduced stroke, works an arm on the rocking shaft D, through an
angle which can be varied by adjusting the pin for the connecting link along the
slot in the arm: The rod R also works one end of a beam H the other end of
which is worked by the piston of a subsidiary cylinder P controlled by that of a
cataract cylinder O, so that the rocking shaft C is worked from the middle of the
beam H with a differential motion depending upon the relative movements of the
rod Rand of the subsidiary piston P.
In applying this arrangement of valve gear to the vertical construction of
compound engines above described, the lever on the shaft receiving differential
motion is made double ended and has a second lever pivotted to each end thereof,
the one such lever being made to actuate the steam valve at one end of the high
pressure cylinder, and the other being made to actuate the steam valve at its
other end. And in like manner the valves of the low pressure cylinder are worked.
Both these lovers are actuated by the shaft that receives rocking motion from the
engine piston.
3
Fig. 3 illustrates this arrangement as it would be applied to the vertical
cylinders shewn in Fig. 1. C and D are the rocking shafts, worked as shewn in
Fig. 2, Chaving the differential motion and working a beam which has pivotted at
its ends E bell crank levers that have one arm of each linked by rods G H to
an arm on the rocking shaft D, while the other arm F of each works the valve
rod A.
i
In applying the said valve gear to horizontal compound pumping engines in
which the high and low pressure engines are in line with each other, I, according to
one arrangement, place the steam valves to the front ends of both cylinders on one
side of the axial line of the engine, and the steam valves to the back ends, on the
opposite side of the axial line, the exhaust valves being arranged in precisely the
same manner, and the passages by which the steam and exhaust valves at each end
of the cylinder are made to communicate with each other being made to cross over
from one side of the axial line to the other, while the passage of the exhaust valves
of the high pressure cylinder is made to communicate with the passage of the steam
valves to the low pressure cylinder.
Fig. 4 is an end view and Fig. 5 is a plan of the two cylinders with their steam
and exhaust connections thus arranged. S is the inlet for high pressure steam
leading to the steam valves A A of the high pressure cylinder of which B B are
the exhaust valves communicating with AA¹ the steam valves of the low pressure
cylinder, of which B' B are the exhaust valves communicating with the exhaust
outlet E. Fig. 6 shews to an enlarged scale the arrangement of the valve gear.
The two shafts C and D, worked as described with reference to Fig. 2, are in the
axial line of the two cylinders, so that all the valves on each side can be worked
correctly therefrom. Thus on the one side of C, the right side as shewn in Fig. 6,
are the pivotted levers for working the steam valve A at one end of the high
pressure cylinder and A' at the same end of the low pressure cylinder, and on the
left are the levers that work by differential motion the exhaust valves B and B at
the same ends of the two cylinders. And in like manner at other parts of the
length of the shafts C and D are similar arrangements inverted for working the
valves at the other ends of the two cylinders.
According to another arrangement of such last described engines, I place all the
steam and exhaust valves in line with each other, the two steam valves to the high
pressure cylinder being placed inside and the two exhaust valves outside, while the
two steam valves of the low pressure cylinder are placed outside and the two
exhaust valves inside. The steam valves of the high pressure cylinder are then
connected by one pipe or passage, the exhaust valves of the low pressure cylinder
by another pipe or passage, and the two exhaust valves of the high pressure
cylinder with the steam valves of the low pressure cylinder by a third pipe or
passage,

page_text: 1 f
Fig. 7 is a plan and Fig. 8 an end view of the cylinders and passages thus arranged.
The high pressure steam supply S communicates with the steam valves valves Å A
of the high pressure cylinder, the exhaust valves B B of which communicate with the
steam valves A' A' of the low pressure cylinder, and the exhaust valves B' B' of
the latter communicate with the exhaust outlet E. Fig. 9 shews to an enlarged
scale the gear for the valves thus arranged, the two rocking shafts C and D being
mounted on opposite sides of the axial line of the cylinders.
In this arrangement the stem M of each valve has a double ended lever such
as K and L pivotted to it. The one end of this lever is actuated by a tappet lever
on the rocking shaft D receiving motion from the motion of the engine pistons,
while the other end is actuated by a tappet on the rocking shaft receiving a
simple motion (ie. not differential) from a subsidiary steam cylinder P and
cataract O. The tappets on the two shafts C and D are arranged at opposite
angles for the levors of the consecutive steam valves, so that while the motion in
the one direction effects the lifting of the one valve, the motion in the opposite
direction effects the lifting of the next valve.
The shaft D which moves in accord with the engine pistons is connected by
a slotted link d with an arm on the shaft C so that while the opening of the valvo
to steam is, by this connection, always made to take place at the same time, the
period of cut off can be varied, as in the previously described arrangements.
Having thus described the nature of my invention and in what manner the same
is to be performed, I claim in respect of Pumping Engines:-
First. At the side of a shaft or pit, connecting the steam piston to one end of a
sway beam, the other end of which is linked to a fixed fulcrum, and the middle is
pivotted to the pumping beam, so that while these connections serve as a parallel
motion to the piston, the mouth of the pit is not obstructed by the cylinder,
substantially as herein described.
Second. Connecting the pistons of both the high and the low pressure cylinders
of a compound engine to a pumping beam, which may work pumps in two
adjoining pita, substantially as described with reference to Fig. 1.
Third. In combination with the steam and exhaust valves of a compound engine;
the lever moved differentially and the rocking shafts C and D for working the
valves so that either can be made to close earlier or later during the stroke, while
the time of opening remains unchanged, substantially as described with reference
to Figs 2 and 3.
Fourth. In combination with the steam and exhaust valves and passages of a
horizontal compound engine, arranged as shewn in Figs 4 and 5, the valve gear
arranged substantially as described with reference to Fig. 6.
Fifth. In combination with the steam and exhaust valves and passages of a
horizontal compound engine, arranged as shown in Figs 7 and 8, the valve gear
arranged substantially as described with reference to Fig. 9.
In Witness whereof I the said Henry Davey have hereunto set my hand and
seal this Fifth day of March in the year of our Lord One thousand eight hundred
and eighty-four.
HENRY DAVEV 10)