IMPROVEMENTS IN STEAM ENGINES
Year: 1870

page_text: LETTERS PATENT to John Frederick Spencer, of Westminster, in
the County of Middlesex, and William Inglis, of Bolton, in the
County of Lancaster, Engineers, for the Invention of “IMPROVEMENTS
IN STEAM ENGINES."
Scaled the 2nd August 1870, and dated the 19th April 1870.
PROVISIONAL SPECIFICATION left by the said John Frederick Spencer
and William Inglis at the Office of the Commissioners of Patents,
with their Petition, on the 19th April 1870.
We, JoHN FREDERICK SPENCER, of Westminster, in the County of
Middlesex, and William InGLIS, of Bolton, in the County of Lancaster,
Engineers, do hereby declare the nature of the said Invention for
'IMPROVEMENTS IN STEAM ENGINES," to be as follows, that is to say:
This Invention comprises various improvements in steam engines of
the compound class in which the steam acts successively in two or
more cylinders, such improvements being more or less developments of
improvements described in the Specification of certain Letters Patent
granted to William Inglis, one of the present applicants, and dated the
23rd November 1864 (No. 3516).

page_text: In one design or general arrangement of engines embodying some of
the present improvements there are two cylinders placed parallel to each
other and acting on separate cranks, which cranks may be at right angles
or nearly so to each other. The two cylinders are fitted with cight
separate valves disposed parallel to each other and transversely to the
plane passing through the axes of the cylinders. These valves are by
preference of the cylindrical or oscillating class, and two of them worked
by liberating valve gear serve to admit steam to the high-pressure
eylinder, a second pair controlling the exhaust from the high-pressure
cylinder into an intermediate space or receiver from which the steam
passes by the third pair of valves into the low-pressure cylinder, finally
exhausting from this last by the fourth pair of valves. The third pair
of valves may also be worked by liberating gear if wished, or any of the
valves, where convenient or preferable, may be worked by link motion or
other suitable valve gear. The cylinders and valves combined, as des-
cribed, may be arranged either vertically, horizontally, or otherwise, and
when placed vertically and inverted form a very convenient arrangement
for driving a screw propeller. When a surface condenser is used in the
arrangement last referred to it is in sonic cases placed over the shaft and
immediately under the exhaust valves which are disposed across the
low-pressure cylinder at its outer side. This is a very advantageous
arrangement with any kind of separate exhaust valves similarly placed.
In another modification of the design the cight valves are placed
parallel to the shaft, a pair being arranged on each sido of each cylinder
whilst a pipe or passage of sufficient size to act as a receiver leads from
the exhaust valves of the high-pressure cylinder to the inlet valves of
the low-pressure cylinder. Or in some cases the high-pressure inlet
valves, or the low-pressure exhaust valves, or both, may be placed at the
side or sides, that is to say, parallel to the shaft, the four intermediate
valves being placed transversely.
In the case of very large engines, or when otherwise desirable, two
simultaneously acting cylinders may be used in place of one low-pressure
cylinder, the piston rods being fixed to one cross head having the con-
necting rod jointed to its middle, whilst the pumps may be worked from
the same cross head or by extensions of the piston rods.
When it is wished to expand the steam successively in three cylinders
the third cylinder may be combined with the other two by means of a
second intermediate receiver and four additional valves, or it may be

page_text: combined with the other two without such intermediate receiver but with
an extension of the arrangement of valves described in the carlier
Specification herein-before referred to.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Frederick Spencer and William Inglis in the
Great Scal Patent Office on the 19th October 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, wc, JOHN
FREDERICK SPENCER, of Westminster, in the County of Middlesex,
and WILLIAM INGLIS, of Bolton, in the County of Lancaster, Engineers,
send greeting.
WHEREAS Ier most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of April, in the year
of our Lord One thousand eight hundred and seventy, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto us, the said John Frederick Spencer and William Inglis, Her
special licence that we, the said John Frederick Spencer and William
Inglis, our executors, administrators, and assigns, or such others as we,
the said John Frederick Spencer and William Inglis, our 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 we, the said
John Frederick Spencer and William Inglis, our executors or adminis-
trators, by an instrument in writing under our, or their, or one of
their hands and scals, 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 Scal Patent
Office within six calendar months next and immediately after the date of
the said Letters Patent.
NOW KNOW YE, that we, the said John Frederick Spencer and William
Inglis, do hereby declare the nature of our said Invention, and in what
manner the same is to be performed, to be particularly described and

page_text: ascertained in and by the following statement in writing, reference being
had to the accompanying Drawings, that is to say:-
Our said Invention comprises various improvements in steam engines
of the compound class in which the steam acts successively in two or
more cylinders, such improvements being more or less developments of
improvements described in the Specifications of certain Letters Patent
granted to William Inglis, and dated the 23d November, 1868,
(No. 3546).
And our present improvements consist principally, 1, in arranging
two cylinders with an intermediate receiver, and with eight valves
placed transversely; 2, in placing a surface condenser over the shaft of
inverted engines and directly under separate transverse exhaust valves
at one end; 3, in placing the cight valves on the sides of the engines
and otherwise; 4, in using two cylinders acting on one cross head in
place of cach low-pressure cylinder; and 5, in extending the arrange-
ments to engines in which the steam is worked successively in three
cylinders.
And in order that our said Invention, and the manner of performing
the same, may be properly understood, we have hereunto appended a
Sheet of explanatory Drawings to be herein-after referred to, and repre-
senting, by way of example, the main features of a pair of engines
embodying some of our said improvements.
Figure 1 on the Sheet of Drawings is a plan of the engines, and Figure 2
is a longitudinal vertical section.
In one design or general arrangement of engines embodying some of
our present improvements there are two cylinders 1, 2, placed parallel to
cach other, and acting on separate cranks 3, 4, which cranks may be at
right angles or nearly so to each other. The cylinders and valves com-
bined as herein-after described may be arranged either vertically,
horizontally, or otherwise; and when placed vertically and inverted, as
shown in the Drawings, form a very convenient arrangement for driving
the screw propeller. The two cylinders 1, 2, are fitted with eight
separate valves 5, 5, 6, 6, 7, 7, 8, 8, disposed parallel to each other and
transversely to the planc, passing through the axes of the cylinders.
These valves are by preference of the cylindrical or oscillating class and
two of them 5, 5, worked by liberating valve gear (such as is in use
with such valves when applied to single cylinders), serve to admit steam
to the high-pressure cylinder 1, a second pair 6, 6, controlling the

page_text: exhaust from the high-pressure cylinder 1 into an intermediate space
or receiver 9 from which the steam passes by the third pair of valves 7, 7,
into the low-pressure cylinder 2, finally exhausting from this last by
the fourth pair of valves S, S. Wrist plates or oscillating discs 10, 11,
are shown as fitted in connection with each cylinder (being indicated by
dotted circles in Figure 2) for transmitting the proper motions to the
several valves from eccentrics on the shaft 12 in any well known way.
The third pair of valves 7, 7, may be worked by liberating gear if wished,
or any of the valves, where convenient or preferable, may be worked by
link motion or other suitable valve gear. When a surface condenser (13)
is used in such an arrangement as that shown in the Drawings we in
some cases place it transversely over the shaft 12 as shown, and imme-
diately under the transverse exhaust valves S, S, which are disposed
across the outer side of the low-pressure cylinder 2. This is a very
advantageous arrangement with any kind of separate exhaust valves
similarly placed.
In another modification of our design differing slightly from the onc
shown in the Drawings, the eight valves (5, 5, 6, 6, 7, 7, 8, 8,) are placed
parallel to the shaft 12, a pair being arranged on each side of cach
cylinder 1, 2, whilst a pipe or passage of sufficient size to act as a
receiver leads from the exhaust valves 6, 6, of the high-pressure
cylinder 1 to the inlet valves of the low-pressure cylinder 2. Or in some
cases the high-pressure inlet valves 5, 5, or the low-pressure exhaust
valves S, S, or both pairs, may be placed at the side or sides, that is to
say, parallel to the shaft, the four intermediate valves 6, 6, 7, 7, being
placed transversely, as in the Drawing.
In the case of very large engines, or when otherwise desirable, two
simultaneously acting cylinders may be used in place of one low-
pressure cylinder, the piston rods being fixed to one cross head having
the connecting rod jointed to its middle, whilst the pumps may be
worked from the same cross head or by extensions of the piston rods.
When it is wished to expand the steam successively in three cylinders
the third cylinder may be combined with the other two by means of a
second intermediate receiver and four additional valves, or it may be
5 combined with the other two without such intermediate receiver, but
with an extension of the arrangement of valves described in the earlier
Specification herein-before referred to, that is to say, with one or with
no intermediate receivers, and with a single pair of valves between the

page_text: first and second, or second and third cylinders, or in both places, as the
case may be.
Having thus particularly described our said Invention and the manner
in which the same is to be performed, we have to state that we do not
restrict ourselves to the precise details herein described or delineated, but
that what we believe to be novel and original, and claim as the
Invention secured to us by the herein-before in part recited Letters
Patent is,-
1. The arrangement of compound steam engines in which a low-
pressure cylinder or a pair of low-pressure cylinders and a high-pressure
cylinder are combined with an intermediate_ receiver_and_eight valves,
substantially as herein-before described.
2. The disposing of a surfaco condenser directly beneath separate
transverse exhaust valves in inverted cylinder engines, substantially as
hercin-before described.
3. The arrangement of three cylinders for the successive expansion of
the steam with two; one, or no intermediate receivers with intermediate
valves arranged accordingly and with separate final exhaust valves, as
herein-before described."
In witness whereof, I, the said John Frederick Spencer, on behalf 2
of myself and the said William Inglis, have hereunto set my
hand and seal, this Nineteenth day of October in the year of our
Lord One thousand eight hundred and seventy.
JOHN FREDERICK SPENCER. (L.s.)