IMPROVEMENTS IN ENGINES TO BE WORKED BY STEAM, AIB, AND OTHER FLUIDS
Year: 1838

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
ELKINGTON, of Northfield, in the County of Worcester, Gentleman, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Sixth day of July, in the second year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said Henry
Elkington, Her especial licence, full power, sole privilege and authority, that
I, the said Henry Elkington, my exors, admors, and assigns, or such others
as I, the said Henry Elkington, my exors, admors, or assigns, should at
any time agree with, and no others, from time to time and at all times during
the term of years therein expressed, should and lawfully might make, use,
exercise, and vend, within England, Wales, and the Town of Berwick-upon-
Tweed, my Invention of "IMPROVEMENTS IN ENGINES TO BE WORKED BY STEAM, AIB,
AND OTHER FLUIDS;" in which said Letters Patent is contained a proviso, that I,
the said Henry Elkington, shall cause a particular description of the nature of
my said Invention, and in what manner the same is to be performed; to be
inrolled in Her said Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said in part recited Letters
Patent; as in and by the same, reference being thereunto had, will more fully'
and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Henry Elkington, do hereby declare the nature of my said Invention, and
the manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof, reference being had to
the Drawings hereunto annexed, and to the figures and letters marked thereon
(that is to say):-
My Invention relates, first, to a mode of working steam expansively in steam
engines in such manner as to obtain more equable power throughout the
rotation of the main shaft than has heretofore been accomplished when working
steam expansively. Figure 1 shews 'the section of so much of a steam engine
as will enable me to describe this part of my Invention. a is the steam
cylinder; b, the induction way for the steam, above the piston; the arrange-
ment of the engine being such as to work the piston in one direction by
the pressure of steam, and in the other direction by the pressure of the
atmosphere; and I prefer that the atmospheric air should be heated to as near
the temperature of the steam to be employed as possible. This may be done
in various ways; the one that I recommend is by placing several tubes in the
flue of the furnace of the boiler, and allowing the air to pass through the same
in its passage to the pipe c..
The nature of steam engines being well understood,, it will not be necessary
to enter into a particular description thereof, but simply to confine myself to
describing my Invention as applied thereto. d is the air pump, on the upper
surface of which is applied a quantity of mercury, in order to aid in the
regulating the varying effects of the pressure of the engine; e is the fly wheel,
fixed in the main shaft f; in one of the spokes of the fly wheel is a slot or
opening in which the crank pin of the shaft g works; h is the connecting rod
from the other end of the beam to that at which the piston rod is attached,
consequently when motion is communicated to the crank shaft g the main
shaft will receive motion therefrom by the crank pin working in the slot above
mentioned; but it will be evident that the effective power with which the shaft f
is driven, being of a varying character, owing to the different degrees of pres-
sure of the steam acting in the cylinder, in order to get regularity or unifor-
mity of
I power during the revolution of the shaft f, that irregularity should be
compensated for, but it will be readily understood that the shaft f being acted
upon by an irregular power, such irregular power may be made uniform to
the shaft by actuating that shaft ƒ by a varying length of lever, which is the
effect of the revolution of the shaft g driving the shaft f at varying distances
from the centre of the shaft f: thus, supposing the piston to be at the upper
part of the cylinder, and the crank pin at the point i, it would be in a position

page_text: g
for driving the shaft f with the shortest leverage it is capable of. On steam,;
say, fifteen pounds weight pressure, entering, say, to one-third the extent of the
stroke, and then cut off, then, as it progressively expands it will decrease in its
force whilst the shaft f will be driven by an increasing leverage by the crank
pin driving the fly wheel progressively at a greater distance from the shaft f,
and thus tend to equalize the effective power in the shaft f, which is commu-
nicated to the shaft 9 in a varying extent. Now, the return stroke of the
engine is effected by an equal force throughout the stroke, but the crank being
arranged for regulating the inequalities of the down stroke, requires now to be
regulated for the other half of its revolution, in order that the power on the
shaft shall remain uniform, as if worked with an equal pressure; to help the
stroke on both sides of the piston with this view, the upper part of the air
pump is in connection with a shallow vessel or trough, in such manner that.
mercury flows into and from the cylinder of the air pump as the piston of the
pump descends and ascends, and it is so arranged that the weight of mercury
at the time that the pistons are at the lowest position, that the weight of
mercury upon the piston of the air pump shall be equal to about five pounds.
weight on the square inch; this is supposing that the steam employed is fifteen
pounds to the square inch, and cut off at one-third of the stroke. In the
ascending stroke of the pistons the mercury will progressively decrease in its
action on the piston of the air pump, and the crank pin in driving the shaft f
will be progressively approaching the centre of the shaft, and consequently
driving it with a decreasing leverage; and, on the other hand, the pressure of
the piston of the steam cylinder during such up-stroke is nearly uniform;
consequently it will be seen that the mercury in pressing with least weight on
the piston of the air pump at the time that the greatest pressure of steam is
acting on the piston of the steam cylinder, and as the steam decreases in
pressure, the weight of the mercury acting on the piston of the air pump
increases in effect, but by such varying of the mercury and such varying of
the crank or length of leverage by which the shaft f is driven, nearly uniform
power will be obtained to the shaft throughout its revolution. I would remark.
that althougli I have mentioned particular pressures of steam, the same may
be varied, so long as the crank and employment of mercury be adjusted to
suit the varying degrees of expansive force that the steam exerts in working:
expansively, and in place of using atmospheric pressure, steam pressure may be
used on both sides of the piston.
I will now proceed to describe the second part of my Invention, which
relates to the construction of a rotary steam engine. Figures 2 and 3. shew
the views of this engine: a is the external cylinder, which is to be bored.

page_text: accurately in the inner surface; 6 is a recess, forming part of or applied to:
the cylinder a; c, c, are the main shafts passing through the end covers:
of the cylinder a, on to the inner end of each of which is affixed an arm
or crank d, one at each end of the piston e; the pistone is a cylinder
accurately turned on the outside, and is mounted on the cranks d, there
being an axis passing through the cylinder e, moving in suitable bearings
in the arms or cranks d; f is a projecting plate, affixed to the piston e,
and forming part thereof, which works through the opening in the cylinder a
into the opening or chamber 6; the ends of the cylinder e and the plates.
have metallic or other packing, which act against the covers of the
cylinders a; 9, 9, are the steam ways and pipes, which are constantly arranged
with cocks or valves to open induction and eduction ways for the steam on:
either side of the piston, as will readily be seen on examining the Drawings.
The engine may be used as a high or. low pressure engine. similar. to other
engines, and there is to be suitable gearing applied to the engine to shut off
the steam and eduction ways at the time that the piston comes in contact with:
the entrance into the chamber or recess b. Supposing the steam to be admitted:
to flow in the direction of the arrows, the pressure would cause the cylinder er
to revolve in contact with the inner surface of the cylinder a, and the pro-
jecting plate would enter into and pass out of the recess b, more or less, as
the cylinder e approaches the recess b, and passes away therefrom'; and it should.
be stated that in using this engine as a single engine, a fly wheel is to be
applied to one of the axes c, and in using it as a double engine, two such
engines are to be so arranged on the shafts c that the. pistons. shall work at
right angles to each other.
Figure 4 shows another arrangement of steam engine, acting on a similar
principle to that shown in Figures 2 and 3; but in this case there are two.
pistons affixed on the same projecting surface plate. f, or in place of having
only a single cylinder a, and a recess for the surface f, there are two cylinders a
and no recess b; in other respects, such as using two axes or shafts c to each
piston, and so uniting the pistons on axes which are carried by the cranks d,
are the same in this engine as in the preceding one; steam being admitted:
through the steamways in the direction of the arrows will drive the pistons.
round in the direction of the arrows, and as the length of leverage of the
driving power of one piston deceases, the other increases, and thus produces
an uniform motion throughout the whole revolution; I would remark that:
this and the preceding engine may be worked by the pressure of heated air,
or, by a flow of water or other fluid, and it will be seen that the plate or.
surface which connects the two cylinders & have grooves formed in, the:

page_text: surface to allow the steam passing beyond the opening (which there is between
the two cylinders a, a), in order that the steam may flow freely from one,
cylinder to the other, but these grooves do not proceed close up to the cylin-
ders e, in order when either of the cylinders e is passing over the opening:
between the two cylinders a, b, that the passage of steam may be cut off:
between them.
I will now proceed to describe another part of my Invention. Figure 5
shews the section of so much of an engine as will enable me to explain this
part of my Invention. It consists of a wheel, the periphery of which is.
hollow, and is shewn to have three valves, which are to be so arranged that
they shall stand across and become partitions to the hollow ring or periphery
of the wheel at all times when they are out of or not working through
a column of mercury, which is contained in one portion of the periphery of
the wheel, and the valves shall open so soon as they enter the column of
mercury, but closed again immediately they quit the mercury; this may readily
be effected by having the valves a to move each on an axis, one end of each
passing to the outside of the periphery, and having an arm or crank affixed
thereto, the crank pins of such arm working in a suitable eccentric groove, to
cause such opening and closing of the valves; b is the steam way, which enters
into a fixed hollow box c, which bears against the nave of the wheel; d, d, d,
are three hollow arms, through which the steam passes whenever their openings
come opposite the box c, such openings being made in the nave of the wheel:
and passing to the respective hollow spokes; e is the eduction way for the
steam; and is a hollow box to which it is connected; this hollow box receives
the steam from the hollow spokes e as they come round; g, g, is a column of
mercury. The height at which such column will stand will depend on the
pressure of the steam, about thirty inches per fifteen pounds (weight) pressure
into a vacuum, and on steam being let on, say, against the lower valve a, the
mercury will act as an abutment and drive the wheel around till the valve a'
comes beyond the lower part of the column of mercury, and is open across
and becomes a partition to the hollow periphery of the wheel; when the steam
coming through its hollow axis will continue the rotatory motion to the wheel.
I would remark that variations may be made in the valves, and other parts of
the engines may be varied, so long as the principle of the engine be retained,
that of the steam working against a column of mercury as an abutment, and
driving round the hollow periphery of a wheel by suitable surfaces or valves
acting as partitions to such hollow periphery.
Having thus described the nature of my Invention, I would have it under-
stood that what I claim is,-

page_text: First, the mode of obtaining greater regularity in steam engines when
working with steam expansively, as herein described.
Secondly, I claim the mode of applying the pistons e moving in steam
chambers or cylinders a, with cranks 6 and axis c, with plate f, as herein.
described.
And, thirdly, I claim the mode of employing a column of mercury as an
abutment in the hollow periphery of a wheel, as above described.
In witness whereof, I, the said Henry Elkington, have hereunto set
my hand and seal, this Fifth day of January, in the year of our"
Lord One thousand eight hundred and thirty-nine.