IMPROVEMENTS IN STEAM ENGINES
Year: 1858

page_text: LETTERS PATENT to George Leedham Fuller, of Lombard Street, in the
City of London, Civil Engineer, for the Invention of "IMPROVEMENTS IN
STEAM ENGINES."
Sealed the 18th March 1859, and dated the 24th September 1858.
PROVISIONAL SPECIFICATION left by the said George Leedham Fuller,
at the Office of the Commissioners of Patents, with his Petition, on.
the 24th September 1858.
I, GEORGE LEEDHAM FULLER, of Lombard Street, in the City of London,
Civil Engineer, do hereby declare the nature of the Invention for "IMPROVE-*
MENTS IN STEAM ENGINES," to be as follows:-
These improvements consist in such combination of steam chests or passages
and steam valves as to enable two or more cylinders (working or having
cranks working at different angles to one another, and being in other respects
of any of the usual forms, whether vibrating or fixed, and of like or different
diameters, as also having valves of the usual or any other construction) to be
worked, as may be required, either jointly at their full powers or on the
continuous expansion system, wherein the steam admitted to the first of the
series afterwards forms the supply to the others, thus giving to two or more
cylinders, so arranged, as extensive a power (or nearly so) of expansion as
could be attained in a single cylinder, with a stroke equal in length to the
sum of the strokes of such cylinders, and at the same time leaving their
joint actual power intact.
And such improvements consist mainly in forming separate, or dividing, the

page_text: steam passages or chests for the valve openings to the tops and bottoms of
such cylinders individually, but common as regards the tops and bottoms of
the series respectively, and then arranging an expansion valve or valves
common to the whole to govern the whole supply.
My improvements also comprise the working of the above expansion valve
or valves, so as to render the same applicable to the purpose required, by
enabling the cutting off of the steam from the different ends of the cylinders
to be independent, and thus to permit of the rate of expansion being
extensively varied while the engine is at work.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George Leedham Fuller in the Great Seal Patent Office
on the 23rd March 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
LEEDHAM FULLER, of Lombard Street, in the City of London, Civil Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of September, in the year of
our Lord One thousand eight hundred and fifty-eight, in the twenty-second
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said George Leedham Fuller, Her special licence that I,
the said George Leedham Fuller, my executors, administrators, and assigns,
or such others as I, the said George Leedham Fuller, my executors,
administrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend, within
the United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN STEAM ENGINES," upon
the condition (amongst others) that I, the said George Leedham Fuller,
my executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same
was to be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date of
the said Letters Patent.
NOW KNOW YE, that I, the said George Leedham Fuller, do hereby
declare the nature of the said Invention, and in what manner the same is to

page_text: be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
These improvements consist in such combination of steam chests or.
passages, and steam valves as to enable two or more cylinders, (working or
having cranks working at different angles to one another, and being in other
respects of any of the usual forms, whether vibrating or fixed, and of like or:
different diameters, as also having valves of the usual or any other construction,)
to be worked as may be required either jointly at their full powers, or on the
continuous expansion system, wherein the steam admitted to the first of the
series afterwards forms the supply to the others, thus giving to two or more-
cylinders, so arranged, as extensive a power (or nearly so) of expansion as
could be attained in a single cylinder, with a stroke equal in length to the sum.
of the strokes of such cylinders, and at the same time leaving their joint actual
power intact.
And such improvements consist mainly in forming separate, or dividing, the
steam passages or chests for the valve openings to the tops and bottoms of.
such cylinders individually, but common as regards the tops and bottoms of.
the series respectively, and then arranging an expansion valve or valves
common to the whole, to govern the whole supply.
My improvements also comprise the working of the above expansion valve
or valves, so as to render the same applicable to the purpose required, by
enabling the cutting off of the steam from the different ends of the cylinders to
be independent, and thus to permit of the rate of expansion being extensively.
varied while the engine is at work.
Having thus stated the nature of my Invention, I will proceed more fully
to describe the manner of performing the same.
DESCRIPTION OF THE DRAWING.
In example, No. 1, (Figures 1, 2, 3,) two cylinders which are supposed
to have their cranks at right angles or thereabouts to each other, are
shown with slide valves of the ordinary form, but made without lap or
cover so as to keep open their respective ports as long as possible, the
chest in which they work is divided, as regards either end, by partitions,
the method of packing which is self-explanatory, but it might also be
done by filling the whole space between them with some elastic material,
also one partition would accomplish the purpose, but two, as shewn, are
preferred, as admitting of easy examination by removing the door o. The
steam being now admitted alternately to either end of the common steam chest
from the valve v, for so much of the length of the stroke of c¹ as required,

page_text: and then cut off, necessitates that shall take its supply either wholly or
partially from the steam so admitted, which on the supply being cut off is at
liberty to expand not only in its own cylinder, but back through its port,
which will be still wide open into c³; while, on the other hand, if the expansion
valve is never shut, both cylinders get a full supply of steam, and can also
then be worked by hand or reversed by their separate valves in the usual
manner. The expansion valve v may be worked, and the duration of the
supply by it regulated as usual, but where only one movement or excentric for
both steam ports is used, I prefer the modification shewn in Example 2,
Figure 4, in which the valve is made in two parts b, c, one attached to a solid
rod, and the other to a hollow one working over it; these rods terminating
respectively in right and left handed screws, taking into the sockets d, to
which the excentric links or rode are attached by means of a loose collar, this
socket being also formed on the outside like a pinion, can be turned by the
face wheel f, and the two parts of the valve brought nearer or further apart
while the engine is in motion, thus virtually altering the lap, and by con-
sequence the duration of time during which the steam is admitted, the length
of travel remaining fixed, and on the two parts being brought quite close,
they will never cover the ports, consequently full steam would be given to both
cylinders.
Example No. 3, Figure 5, shews a simple arrangement where, for two
cylinders intended to work at right angles, or nearly so, with a limited
range of supply, the expansion valve can be amalgamated with that of the
second cylinder c². In this case the steam passes through and the exhaust
outside the slides and 83, the steam passages being provided with a
stop valve, by which the steam can be admitted to either or both at
pleasure, when only to s¹; examination of the Drawing will shew that its own
cylinder cannot possibly be supplied except from the other c¹, the supply to
which, though full open at the commencement of its stroke, must be cut off at
the half stroke by the face on the partition of the valve of c², and as much
sooner as the lap of the said face provides for, while directly steam is admitted
in the passages both cylinders get full steam for the whole of their strokes.
The necessary division between the ends of the cylinders is completed by the
stationary blocks or plates between the valves, which are kept in their places
by lugs at the top and bottom of the chest, and are intended to be kept up to
the backs of the valves by a slice of india-rubber or other elastic packing
between them, as shewn, or they could be formed as folding wedges or with a
middle wedge, as in the case of the packing ring in Examble 5, tightened by
screws and nuts passing out at the top or bottom (or both) of the steam chest

page_text: These arrangements, provided the second cylinder is larger, and by con-
sequence under full steam more powerful than the leading one, have the
additional advantage of materially simplifying the working gear of such
engines, for full steam being first admitted the valve of c³ only need be
worked by the usual slot link motion for the purpose of reversing, or (in the
last example) of modifying the supply, or with hand gear if such be preferred,
since the other, if simply attached to a loose excentric and driver, could not
fail to come round correctly to the lead of that belonging to the larger
cylinder.
Example No. 4, Figures 6 and 7, shews, first, the applicability of equalibrium
slide valves formed of blocks, with ports passing through them, to this mode
of working, which can be packed similarly to the manner described for the
stationary block forming the partition in Example 3, or like the ring in
Example No. 5, in which case the ends of the valve rods might form the
tightening screws; secondly, the use of separate and distinct equilibrium disc cut
off valves, to either end, the spaces between the seats of which, distinct as regards
each other, form, as will be seen, perfectly free connections between the cor-
responding ends of the separate cylinders. The rod of one pair of these valves
here passes through that of the other, which is hollow; but that is not a neces-
sity, since they might be brought separately out at either end of the steam chest.
Also it will be apparent that if the cylinder valves in this arrangement opened
to the exhaust inside like the equilibrium valve, sectioned in Figure 17, for
instance, the inner stuffing box t, and the partitions p, p, which separate the
exhaust passages from the steam might be dispensed with. These disc valves
can be worked by any known form of cam, or by the one herein-after
described.
Example 5, Figures 8 and 9 show the trunnions for two vibrating cylinders,
with segmental reversing valves in lieu of the ordinary slide valve arrangement
working in a casing common to both, through which expansion from one to
the other can take place after the fresh supply is cut off at the ports v, v, one
of which supplies the tops, and the other the bottoms of the cylinders. The
method of reversing, by altering the position of the ring, will be obvious on
inspection, as also the method by which it can be kept tight without undue
pressure, by means of vulcanized india-rubber, or short spiral springs placed on
the tightening bolts at the heads and nuts; but these details not being
essential to the subject exemplified, but rather belonging to the second claim of
my Patent of August 17th, 1853, it is not necessary further to refer to them.
In this, and the remaining examples, the small expansion slides shewn are
intended to be worked separately.

page_text: Example No 6, Figures 13, 14, and 15, shew three cylinders arranged
on the principle of continuous expansion, and shows clearly the distinctive
features in the arrangement of the steam passages of such engines, which are
claimed as new, and which inspection will shew to be common in all the
examples. In this case a gradually increasing size of cylinder is shewn, in
fact, it would only be applicable for very high-pressures generally when more
than two cylinders are intended to be worked conjunctively, as herein.
described. I prefer to arrange them at angles with each other, because, by so
doing, it will be found that a proper arrangement of cranks will perniit of
the steam passing from one to the other for a longer period than can be
obtained with their centres in one line; for instance, reference to the Diagram
over Figure 18 will shew that if the cylinders c³, c², c³, of the present example
were respectively placed at an angle of 30° with each other, c' being in such
case the perpendicular one, and the relative position of their cranks being
retained, as in the Diagram over Figure 15, the result would be, that c³ and c³
would begin to afford expansion room to the steam at one-third and two-thirds
of the stroke of c¹ respectively, instead of at one-half, and at the end of it as-
when perpendicular. The same result is also obtained in the following
example, by making the perpendicular cylinder, and attaching and c³ to
one crank, which is set at right angles to that to which c¹ is attached, and it
will be obvious that other arrangements of the angles of the cranks and
cylinders with each other may be used according to the length of time con-
nection between the cylinders is required.
Example 7, (Figures 16, 17, and 18,) shews the practicability of applying
pipe connections where the cylinders to be combined have separate steam
chests, as also a method of attaining, for vibrating engines with the ordinary
valve motion, that separation between the top and bottom supply which is
essential for my purpose. Figures 17 and 18 shew the position of the steam
chests, and a section, and face views of the valves used, which can be packed
by methods before alluded to, the projecting faces on the double steam pipe
against which they work are in this example shewn to form also one of the
trunnions of each cylinder, but this is not an essential. Also, if preferred, the
exhaust could be taken out through the centre of the steam ways, or outside
them, as in Example 4, instead of round the cylinder and out at the opposite
trunnions as drawn. If this mode of connection were adopted for fixed
cylinders, the inner side of the steam pipes could be made to coincide with the
back of the steam chests, and, the distance from port to port of the cylinders
be thus shortened. Examples 8 and 9, (Figures 10, 11, and 12,) shew the
improved double variable cam motion, by which I prefer to move the valves of

page_text: the separate expansion ports; the same being also applicable to any valves
between the opening and shutting of which it is wished to be able to vary the
length of time.
The first Example, No. 8, is adapted for immediate application on the
main shaft, the other, No. 9, for an intermediate shaft driven from it by any
known means, causing a uniform motion with it. k, k, is a fixed disc or cam
revolving with the shaft in question, the projection on which opens each
valve alternately at the proper time for the admission of steam, by means of
the rollers at the end of the rods r, r; l, l, is an outer disc kept close to the
other by being screwed to a bevilled segment m, m, moving in a groove on
the back of the latter, or it may be screwed to a loose ring on the inner boss.
This outer disc has a rim projecting over the other with a projection inwards
which moves the rollers in an opposite direction, and consequently shuts off
the steam. This outer disc is provided with a telescope boss, the two parts
of which are made to revolve together by means of a sliding key as shewn (or
by being made oval or excentric,) and the one in contact with the shaft is
provided with a short key moving in a spiral key way of such length as to
cause the projection on this disc to move quite round from one side to the
other of the fixed cam, by which means steam can be kept on for a longer or
shorter period of the whole revolution at pleasure. Provision is made for
altering its position while the engine is in motion, either by terminating the
advancing boss with a series of grooves as at 9, g, which form teeth by which
the pinion p can move it forward when turned for that purpose, or by means
of a hollow screw sliding on the shaft as at h, h, Figure 11, screwed backward
or forward as required by the hand wheel w, w, which can be held stationary
by one of the same standards that support the cam shaft. If preferred, it is
obvious that the boss of the moving cam may fit close to the shaft, and that
the spiral may be put on the outside of it, the advancing portion being then
enlarged to move over this part, and being supplied with a key to work in the
spiral, its keyway on the shaft being then parallel to the same, the valve
rods may be attached direct to the rollers, and move one over the other as
(for the sake of simplicity) shewn in the examples herein given, or be con-
nected with them by links, or links and levers, and may be made capable of
being disconnected while the engine is in motion or being reversed. Also,
the arrangement might be so varied that the outer cam should be the fixed
one and the inner the adjustable one, though I prefer it as shown. The
rollers can be kept in line by small guides if required, or put at the end of
levers, which might be furnished with counterbalanced weights to assist the
inertra of the slides or valves in keeping them close to the discs, or to balance

page_text: the valves if necessary. When slides are used with these cams, and a large
area of port required, I prefer using the form known as the "gridiron" slide,
as requiring a less travel, and by consequence smaller cams.
Having now fully explained the object of my improvements, and shewn
that they do not consist in using any particular or relative sizes of cylinders,
or in their relative positions, or that of their parts or adjuncts, I wish it to be
clearly understood that I make no claim to any of the mechanical parts
separately; but I claim as new the combining of a perfect separation of the
top and bottom supply of steam (or other vapour) to a pair or series of cylinders
and a complete and free communication between the ports of the correspond-
ing ends of such cylinders, with valves to each cylinder capable of admitting
steam from end to end of the strokes of the pistons (or as nearly so as
possible) together with such regulating valve or valves to a common supply
port or ports as will admit of full steam being supplied to both or all the
cylinders, or of cutting off the supply of steam during any portion of the
revolution of the shaft as may be desired.
And I also claim the combining an inner and outer cam acting in contrary.
directions on the same roller or rollers, so that one cam is a fixture. on a shaft
common to both, and the other moveable around or within it, and by means
of certain spiral keys, pinions, or screws, making the moveable one adjustable
to any relative position with the other, and thus altering the period of
alternation, while the shaft to which they are attached is in motion.
In witness whereof, I, the said George Leedham Fuller, have hereunto
set my hand and seal, this Eleventh day of March, in the year of our
Lord One thousand eight hundred and fifty-nine.
Witness,
JNO. ALCOCK.
GEO. L. FULLER. (L.S.)