Improvements in Compound Steam Engines.
Year: 1891

page_text: Date of Application, 27th Jan., 189-Accepted, 2nd May, 189
COMPLETE SPECIFICATION.
Improvements in Compound Steam Engines.
.I STEPHEN WILCOX of No. 30 Courtland Street, New York City, in the State
of New York, United States of America Engineer do hereby declare the nature of
this invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement and accompanying
drawings
This invention relates to compound engines for either land or marine purposes
and it consists in the embodiment in a triple or other expansion engine of a series of
single acting low pressure cylinders axially aligned with the double acting high
pressure and intermediate cylinders and having connected pistons which are
connected to a single crank upon the driving shaft, the steam distributed to the
series of cylinders in alignment being governed by the same valve gear.
To render my invention perfectly clear I will now proceed to describe the same
with reference to the annexed drawings.
Figure 1 is a general front elevation.
Figure 2 a plan view.
Figure 3 a sectional elevation taken on the line, Figures 2 and 4.
Figure 4, a horizontal section taken on the line Figure 3.
Figure 5, a vertical sectional elevation taken at right angles to Figure 3, on the
line thereof, looking in the direction indicated by arrows.
Figure 6, a detail view showing in vertical section (on, the line 3, Figure 3)
one of the low pressure cylinders; the piston being removed and
Figure 7, a detail view representing the steam chest and valves of the high
pressure cylinders as they would appear taken in section on the line
Figure 4.
t
The illustrations show a triple expansion engine as one appropriate embodiment of
my invention; and of which 1 represents the high pressure cylinders, 2 the intermediate
cylinder, and 3, 3' two single acting cylinders sharing equally the function of a
third or low pressure cylinder.
The vertical space occupied by the low pressure cylinders 3, 31 is substantially
equal to that usually occupied by the cross heads and guides; the aggregate height
of the engine being thus normal, or corresponding to that of the ordinary con-
struction referred to; which such amount of horizontal or shaft length of the
engine as corresponds to the diameter of the low pressure cylinder combined with
the receiving chamber from whence its steam is supplied, when located on a
common level with the other cylinders, is dispensed with, rendering the engine very
compact and self-contained. The eccentrics 11, 12 are cach controlled by a
governor 13, the same having any construction such as that well known to the art,
and not requiring detailed description here.
The cylinders 3, 3' compose a part of the frame of the machine, supporting the
cylinders 1, 2, above them. By this feature of location of the cylinders 3, 3, the
centre of gravity of the structure as a whole, is lowered and an increased length of
the connecting rods 20 permitted without rendering the engine top heavy. The
upper cylinders 1, 2, are supported solely by the necks 14, fitting the flange 16, of
the low pressure cylinders; (and the cylinders 1, 2, are also braced partially by
the branched pipe 15); but such upper cylinders 1, 2, may be additionally
supported by suitable frames or braces in situations where necessary.
The frame 4, and its base 5, supporting the machine is of course susceptible of
various construction, according to circumstances of situation; whether upon a
stationary foundation, or within a marine vessel. An enclosed or box form of

page_text: supporting frame is herewith illustrated as one form of construction suitable to a
stationary engine.
The shaft 6, is supported in bearings 7, in the base 5, and the cranks 8, 81,
are fixed at the usual angle of 90 degrees with reference to one another about the
axis of the shaft.
The pistons 21, 22 of each of the upper and lower cylinders respectively are
connected by piston rods 23, passing through suitable packings 24, in the supporting
necks 14; and the bearing surfaces of the single acting pistons 22, are elongated
sufficiently to afford a proper resisting wear against the side thrust of the connecting
rods 20, connected thereto.
25, 26, are balanced. piston valves for the high pressure. cylinders 1 and 2,
respectively; the induction side being between such pistons and the eduction at the
opposite or exterior ends thereof; the reciprocation of each being imparted by the
respective eccentrics 11, 12, and their rods 28, through sliding bars 27. The piston
valve 26, is employed in duplicate as seen in plan view in Figure 4, for the purpose
of duly enlarging the capacity thereof; and the two valve stems are connected by
a yoke 35 (Figure 3) upon the upper end of the slide 27, thereby operating in
unison.
30 are the induction, and 31, the eduction valves of the "Corliss" type, for the
low pressure cylinders 3, 31; both operated from wrist-plates 32, cominon to each;
which wrist-plates are also driven by the eccentrics 11, 12, through the rods 28, of
the latter, and the connecting rods 33.
The combined receiving chambers 9, 10, the structure whereof unites the upper
part of the machine, includes two separators. 40, 41, for eliminating condensed
portions of steam during its transmission from one to another of the successive
cylinders, suitable drip or discharge valves being provided for removing the
accumulated water in the wells of the separators. concentrate the receiving
chambers 9 and 10 (Figure 4) of the primary and intermediate cylinders 1, 2,
respectively, into one structure; separating the said cylinders only sufficiently to
leave convenient space for also concentrating all the parts of the valve gear below
such chambers 9, 10, and between the cylinders.
I will, herein describe, briefly, the structure of the receivers, and the course of
the steam therein sufficiently to make clear the co-operative relation between the
other parts of the machine forming the subject of my invention.
50, is the initial pressure steam pipe connecting to the induction side 60, of the
valve 25 the steam being distributed to the cylinder 1, through the ports 52.
The partly expanded steam from the cylinder 1, issuing from the eduction
sides of the valve 25, is delivered through the passages 53, to the opening 54 of the
first separator 40; (the current from the lower passage 53, passing upward through
the conduit 55). The current of steam thence enters tangentially the space between
the inner and outer concentric pipes of the separator 40,. being directed by the
inclined bridge 56, (Fig. 3), following a spiral downward course, the water
separating centrifugally. The dry steam current then returns upwardly through
the inner concentric pipe and is transferred through the goose-necked pipe 57, into
the first receiving chamber 9. From the receiving chamber 9, the steam is then
admitted to the induction side 60¹, of the valves 26, and distributed to the ports 59,
of the intermediate cylinder 2; (the connecting passage 58, Figure 3, effecting
communication in the direction indicated by the arrow 58', in Figure 4). The
further expanded steam delivered from the eduction sides of the valves 26, through
the passages 61, is conducted to the common opening 62, (the current from the
lower passage 61, passing upward through the conduit 63). The current of the
steam is then admitted tangentially between the inner and outer concentric pipes of
the separator 41, as before described with reference to the first separator; a
downward spiral course being followed, and a subsequent upward course through
the inner concentric pipe and goose-necked pipe 64, delivers the steam into the
Recond receiving chamber 10. From the receiving chamber 10, the steam is

page_text: conducted through the bifurcated pipe 15, and distributed to the two single acting
cylinders 3, 3, by the induction valves 30, and subsequently exhausted through the
eduction valves 31, to the condenser or atmosphere.
70, are automatic relief valves (see Figure 7) capable of opening toward the
pressure on the induction side of the cylinder valves to relieve the pressure of
cushioning compression when the same exceeds the initial pressure such as contained
on said induction side. The valves 70 are of the check valve type, seated against
openings from the ports 52, or 59, and discharge the steam into the steam chamber 60
instead of a waste passage, (said valves being applied to both cylinders 1 and 2);
and to the above purposes they control communication of said ports with the steam
chests 60, or 60. The valves 70, are retained upon their seats by suitable springs
such as usual to check valves, and they are thereby retained in a closed position
before pressure is applied in starting the engine.
In the operation of my invention, the two single acting low pressure cylinders
share equally the expanded steam from the receiver 10 of the intermediate cylinder,
and co-operate with the same motive effect as would be derived from one double
acting low pressure cylinder located in the usual lateral conjunction with the other
cylinders. In order to counteract the effect of the impulses of the low pressure
cylinders that are concentrated in the downward stroke, a greater degree of
cushioning compression may be employed in the lower ends than in the upper ends
of the cylinders 1, 2, by a proper adjustment of the valves. The cranks 8, 8',
not, however, essentially placed at a right angle to one another about the axis of
the shaft. They may be placed at a half circle apart, or substantially opposite, as
commonly practised heretofore in compound engines, distributing the said impulses
at equal intervals in the rotation of the shaft.
are
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. A compound engine consisting of a double acting high pressure cylinder, and
a single acting low pressure cylinder located adjacent to and in alignment with said
high pressure cylinder, and having connected pistons which are connected to a
single crank, and provided with a single valve gear that governs the distribution of
steam in the respective cylinders, substantially in the manner described.
2. The combination in a compound engine of two or more double acting cylinders
located in lateral relation single acting cylinders arranged in common axial
alignment severally therewith, provided with connected pistons within the commonly
aligned cylinders, their shaft crank connecting rods being severally pivoted upon
and guided by the single acting pistons, and a valve gearing that governs the
distribution of steam-in said commonly aligned cylinders.
3. The combination in a compound engine, of a double acting high pressure and
intermediate cylinder located in lateral relation, single acting low pressure cylinders
severally located in common axial alignment with said high pressure and inter-
mediate cylinders, connected pistons in the aligned cylinders and steam distributing
valves and successive passages for the same, delivering the steam first to the said
double acting cylinders in series consecutively, and then to the distributing valves
of the single acting cylinders, the respective supply passages of the latter being
connected in common.
pressure
4. The combination in a compound engine, of a double acting high pressure
cylinder and receiver, a double acting intermediate cylinder and receiver located in
lateral relation to the high pressure cylinder, and single acting low
cylinders severally aligned with the said high or intermediate pressure cylinder,
having pistons connected in common therewith as described and having the
induction side of their distributing valves connected in common with the final
receiver of the said double acting cylinders.
5. The combination in a compound engine. of a double acting high pressure and

page_text: intermediate cylinder, located in lateral relation; single acting low pressure
cylinders axially aligned therewith; connected pistons in the aligned cylinders;
reciprocating steam distributing valves for the double acting cylinders and rock
motion distributing valves for the single acting cylinders, together with connecting
valve gearing for operating all the valves of the respective aligned cylinders.
Dated this 26th day of January 1891.
DUTTON & FULTON,
1, St. James Square, Manchester, Agents.