Improvements in Multiple Expansion Engines.
Year: 1893

page_text: Date of Application, 17th Mar., 1593-Accepted, 13th May, 1893
COMPLETE SPECIFICATION.
[Communicated from abroad by CHARLES CAMPBELL WORTHINGTON, of
Irvington, in the State of New York, United States of America, Mechanical
Engineer.
Improvements in Multiple Expansion Engines.
I HENRY EDWARD NEWTON of The Office for Patents, 6 Bream's Buildings,
Chancery Lane in the County of London, Patent Agent, do hereby declare the
nature of this invention and in what manner the same is to be performed, to be
practically desantained in and by the following statement:-
This invention relates generally to multiple expansion engines employing three
or more cylinders in line. but it has more especially reference to that class of
multiple expansion engines known as triple expansion engines, or engines employing
only three cylinders, and the invention is described by my foreign correspondent in
the following terms, that is to say:
The object of the present invention is to provide an improved construction of
triple-expansion engine, and especially to render the pistons of the respective
cylinders more readily accessible and removable than in constructions of this class
heretofore in use.
As a full understanding of the invention can best be given by a description of an
engine embodying the same, such description will now be given in connection with
the accompanying drawings forming part of this Specification, and the features
forming the invention specifically pointed out in the claims.
or
It will be understood that the invention broadly is applicable generally to
For the
duplex, horizontal or vertical.
multiple expunction engines ingle
purpose of illustrating the invention, however, I have shown a construction
embodying the invention in the preferred form, as applied to a duplex horizontal
direct-acting pumping triple-expansion engine of the class known as the Worthington
Duplex Pumping Engine, and from the illustration and description of this con-
struction, and certain modifications thereof, the application of the invention to
other engines will be readily understood.
In the drawings :
Figure 1 is a sectional plan of a pumping engine of the special class referred to
embodying my invention in the preferred form with the cylinders arranged in line,
the section being taken centrally through the steam end of one side of the engine.
Figure 2 is a diagrammatic sectional plan of a modified construction, it being
understood that the construction shown therein may form a single engine or one
side of a duplex engine.
Figures 3 and 4 are similar views, showing modifications embodying some of
the features of my invention, as applied to engines in which the cylinders are not
arranged in line.
Referring now especially to Figure 1, A, B, C are, respectively, the high pressure,
intermediate pressure and low pressure steam cylinders; a, b, c, the corresponding
pistons, and D, the water cylinders on each side of the engine. The steam is
delivered to the high pressure cylinder A through induction pipe E and exhausted
from the high-pressure to the intermediate pressure cylinder through pipe F, thence
to low pressure cylinder through pipe G, and thence to the condenser or elsewhere
through the exhaust H. The steam valves may be of any suitable construction
and operated by any suitable valve movement, but cut-off valves on only the high
pressure cylinder are preferably used, and rotary valves thus arranged as shown,
these valves being operated by the lever valve motion I, connecting rods 1, and
cranks 2 on the valve stems, as usual in this class of engines, except that a single

page_text: central main valve is used on each evlinder. It will be understood that the valve
motion may be actuated from any suitable moving part of the engine.
.
Referring now to the arrangement of pistons and piston-rod-, as shown in section
on one side of the engine, d is the main piston-rod, through which the power from
the three cylinders is applied, this rod being connected to the pump-plunger in any
suitable manner, and upon this piston-rod is a cross-head, to which the pistons
of the three eylinders are connected, the cross-head bring secured to the rod by a
key, as shown, or in any other suitable manner. The high-pressure piston a is
connected to the co-head centrally by a rod of suflicient size to carry the high
pressure piston head, the piston being secured on the end of the rod, preferably
y a nut 3, as shown, and as usual in piston constructions when the piston can he
placed upon the end of the rod. The rod is preferably separate from the main
piston-rod d and secured to the cross-head in line with the rod d by a separate
key, as shown; but it will be understood that the piston-rod d may be extended
through the cross-head to form the rod, in which case it is preferably reduced in
diameter to avoid reducing the effective area of the piston a. The cross-head is
connected to the low-pressure pistone by rods, extending outside the high and
intermediate pressure cylinders, and connected to the cross-head e and piston e at
their opposite ends, preti rally by nuts 3, as shown. The intermediate pressure
piston is connected directly to the low-pressure pistone by its piston-rad h.
secured at its opposite ends to the pistons & prefirably by mut- 3, as shown.
.
Each of the cylinders, therefore, has one one head through which the piston rod
does not pass, and these heads o are made removable in the usual manner, the two
inner cylinders A B being separated sufficiently to find space for the removal of
the respective heads o and pistons a b.
It will be seen that, in this construction, each of the three pistons is readily
accessible by removing the respective cylinder heads o, that each of these heads
may be removed reality and without interference with any piston-rod or stuffing
box and that, as each of the pistons is carried at the end of its rod, they may all
be removed by simply slacking off the respective mats 3. In this construction also,
the use of key in the cylinders may be entirely avoided, and the area of the smaller
pistons need not be reduced by rods larger than sufficient to carry their respective
individual loads. The direct course of steam between the high pressure and
intermediate and low pressure cylinders is retained also, and, in case of repairs,
either the intermediate or the high pressure pistons and valves, or both, could be
removed and the engine run with the remaining cylinders or cylinder.
While I prefer the arrangement thus far described as forming the best construc
tion now known to me embodying my invention, and this specific arrangement in
itself forms a part of the invention, other arrangements may be used embodying
the broad features of the invention, and securing many of the advantages attainable
thereby.
Thus in Figure 21 have shown a modified construction in which the intermediate
and low pressure piston connections are reversed, the low-pressure piston rod being
connected to the intermediate pressure piston, and the latter in turn to the cross-
head. In this construction the cross-head is placed on the main-piston rod d, and
the high-pressure piston a secured to the same by rod as before. The intermediate
pressure piston is connected to the cross-head e by rods i passing outside the
high-pressure cylinder A, and the low-pressure pistone is connected to the inter-
mediate pressure piston & by central-piston rod k
In this modification it will be seen that the pistons ae of the high and low
pressure cylinders are readily accessible by removing their respective cylinder
heads o, and may be removed by simply slacking off the nuts 3, as in the construction
previously described, but the intermediate pressure piston b is not so readily
accessible and removable as the rods m pass through its removable head o.
piston is accessible within the space between the cylinders A, B by sliding the
hend o of the cylinder B outward upon the rods m, and the piston may then be
removed by removing the nuts on the opposite sides of the piston by which it is
This

page_text: secured on the rods i and . In this construction, moreover, if desired, the inner
head of the low-pressure cylinder C may be constructed to permit the removal of
intermediate pressure piston through the same, so that this piston 6 may be
removed by removing the low-pressure piston, opening the inner head of the
cylinder C, and slacking off the nuts by which the rods i are secured to the
piston b.
In Figures 3 and 4 I have shown constructions embodying certain of the features
of my invention, but in which the cylinders are not arranged in line. In these
constructions the high and intermediate pressure cylinders A B are placed on
opposite sides of the line of the main-piston rod d, and the low-pressure cylinder C
is mounted centrally and in line with the main-piston rod d outside the cylinders A B.
The cross-head is used as before, and the high and intermediate pressure
and
piten connected to apposite ends of the same by their respective rods /
the low-pressure pistone is connected centrally to the cross-head and main-piston
rod d by its piston rod n, the cross-head e being placed either between the pump
cylinder D and cylinders A B as shown in Figure 3, or between the low-pressure
cylinder C and the cylinders A. B as shown in Figure 4.
"
m,
In these two constructions it will be seen that each cylinder has one head through
which the piston rod does not pass, so that the head and piston may be removed
without any interference with the piston rods or stuffing box. Keys are avoided.
and all unnecessary reduction of the area of the smaller pistons is prevented, and
it is possible to run the engine with any one or two of the cylinders in case of
repairs. These constructions do not, however, embody that especially important
feature of my invention, consisting in providing constructions securing these
advantages with the arrangement of the cylinders in line.
I have shown only the preferable modified arrangement embodying my invention,
and it will be understood that the invention is not limited to the arrangements
shown, but that other arrangements may be made without departing therefrom.
It will be understood, also, that my invention is not to be limited to a triple-
expansion engine or to an engine employing only three cylinders, but that it is
applicable generally to multiple expansion engines employing three or
cylinders in line.
more
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed (as communicated to me
from abroad), I declare that what I claim is :-
1. A multiple expansion engine having three cylinders arranged in line with an
independent piston-rod for the inside cylinder passing through the inner head of the
cylinder, and with the pistons of the two outer cylinders connected to the innin
piston-rod by connections passing outside the inside cylinder, and constructed to
provide space between the two inner cylinders for access to their pistons, substantially
as described.
2. A multiple expansion engine having three cylinders arranged in line with the
high pressure cylinder placed inside and having an independent piston-rod passing
through its inner head, and with the low and intermediate pistons connected to the
main piston-rod by connections passing outside the high pressure cylinder, and
constructed to provide space between the two inner cylinders for access to their
pistons, substantially as described.
3. A multiple expansion engine having three cylinders arranged in line in the
order of expansion with the high pressure cylinder placed inside and having an
independent piston-rod passing through its inner head, and with the intermediate
pressure piston connected to the low pressure piston by an independent rod and the
low pressure piston connected to the main piston-rod by connections passing outside
the intermediate and high pressure cylinders, the engine being constructed to
provide space between the high and intermediate pressure cylinders for access to
their pistons, substantially as described.
4. The combination with the cylinders A, B, C of a multiple expansion engine

page_text: arranged in line with the high-pressure cylinder inside and provided with space
between the two inner cylinders for access to their pistons, of the main-piston rod d,
cross-head on said rod, high-pressure piston rod connected to said cross-head or
rod, connections between the intermediate and low pressure pistons, and rods outside
the high-pressure cylinder connecting the intermediate and low pressure pistons to
the cross-head, substantially as described.
5. The combination with the cylinders A, B, C of a multiple expansion engine
arranged in line in the order of expansion with the high-pressure cylinder inside,
and provided with space between the high and intermediate pressure cylinders for
necess to their pistons of the main-piston rod d, cross-head on said rod, high-
pressure piston rod connected to said cross-head, rods outside the intermediate
and high pressure cylinders A, B, connecting the low-pressure piston with the
cross-head e, and intermediate piston rod h, connected to the low-pressure piston,
substantially as described.
6. A multiple expansion engine, having its cylinders arranged in line, and
having its pistons connected to the main piston-rod by connections independent of
one head of each cylinder, and constructed to provide spare for access to each
piston at the end of the cylinder through which the connections do not pass,
substantially as described.
7. A multiple expansion engine, having its cylinders arranged in line, and having
two inner cylinders separated to provide space for access to the pistons of said
cylinders, and having its pistons connected to the main piston-rod by connections
independent of the outer head of the inner one of said two inner cylinders,
substantially as described.
8. A multiple expansion engine, having its pistons connected to a main piston-rod
by connections independent of one head of each cylinder, and constructed to
provide space for access to each piston at the eml of the cylinder through which
the connections do not pass, substantially as shown and described.
9. A triple expansion engine, substantially as shown in Figure 1.
10. A triple expansion engine, substantially as shown in Figure 2.
11. A triple expansion engine, substantially as shown in Figures 3 and 4.
1049
NEWTON & SON,
Agents for the Applicant.