IMPROVEMENTS IN COMPOUND SURFACE CONDENSING MARINE STEAM ENGINES, PARTLY APPLICABLE TO OTHER COMPOUND ENGINES
Year: 1884

page_text: I, DANIEL ADAIR CORMACK of Twenty-seven Quality Street Leith, Marine
Engineer do hereby declare the nature of my Invention for IMPROVEMENTS IN
COMPOUND SURFACE CONDENSING MARINE STEAM ENGINES, PARTLY APPLICABLE
TO OTHER COMPOUND ENGINES, to be as follows :-
This Invention consists of a general arrangement of compound surface condensing
steain engines, suitable either for land or marine purposes; of which the two
cylinders are in one casting placed side by side upon one column which is cast
hollow to form a vacuum chamber. The steain supply is controlled by one slide
valve, worked by one eccentric. The slide valve has ports corresponding to those
of cylinder face which latter are seven in number. The three centre ports in
cylinder face open into the exhaust way to condenser. The two ports above and
below next to these 3 abovenamed open to the low pressure cylinder, and the
extreme top and bottom ports open to high pressure cylinder.
The cranks are placed opposite to each other, and the steam in the first instance
is admitted over the end of the slide valve into the high pressure cylinder, at the
same time it is allowed to escape from the opposite end of the high pressure into
the opposite end of the low pressure direct through the passage cast for the purpose
in the slide valve, without being first passed into a receiver which is unnecessary
by reason of the cranks being set opposite to each other.
The line of valve face is parallel with that of crank shaft, instead of being at
right angles to it as usual, and works on one side of both cylinders.
The Invention combines with the foregoing, the use of Chapman's Patent Air
Extractor, connected with a condenser placed outside the hull of a vessel, and
having its hotwell or suction of pump also placed outside; or further, to enclose
the tube or tubes forming the condenser within a chamber or chambers, such
chamber or chambers being within the hull, but communicating direct with
the sea.
Dated this Eighth day of April 1884

page_text: COMPLETE SPECIFICATION.
g
I, DANIEL ADAIR CORMACK, of Twenty-seven, Quality Street, Leith in the
County of Midlothian, Marine Engineer, do hereby declare the nature of my
Invention for IMPROVEMENTS IN COMPOUND SURFACE - CONDENSING MARINE
STEAM ENGINES, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
My said Invention which relates to improvements in compound surface-
condensing marine steam engines, partly applicable to other compound engines,
consists of a general arrangement of compound steam engines suitable either for
land or marine purposes.
When used for marine purposes to be in combination
with a surface condenser, to which Chapman's Patent Air Extractor is to be
connected.
And, in order that my said Invention may be properly understood, I now
proceed to set forth the system, mode, or manner, in or under which the same is or
may bo carried into effect, reference being had to the accompanying Drawings, and
to the letters and Figures marked thereon; that is to say, Figure 1 represents sido
elevation of mechanism constructed according to my present Invention. Figure 2,
represents end elevation of the same.
W
In carrying my Invention into practice, the two cylinders C, C¹ are in one casting
placed upon one column, which is cast hollow to form a vacuum chamber B.
The pistons A, A, work parallel with each other as in other compound engines,
though in different directions at the same time.
The line of valve face D is parallel or nearly so with the centre line of crank
shaft E, instead of being at right angles with it as usual, and works in one side of
both cylinders.
"
The steam supply is controlled by one slide valve D, worked by one eccentric F.
The slide valve D (Figure 2) has ports corresponding with those of cylinder
face G, which latter are seven in number, of which the three centre porta e, e, e,
open into condenser, and are merely the exbaust port sub-divided into three, so as
to allow of a sufficient opening of port with a short travel of slide valve.
The two larger ports l, l, above and below the three above-named, turn to the
left, and lead into the low pressure cylinder C (Fig. 1). The smaller ports p, p,
turn to the right, and lead into the high pressure C₁ of which the piston is
represented in Figure 2 as in ascent.
At the same time, the steam which has already done duty on the down stroke of
the high pressure piston, is allowed to escape from the opposite or top end of the
high pressure into the top end of the low pressure (of which the piston is shewn
in descent) direct through the passage fcast for the purpose in the slide-valve D,
without being first passed into a receiver which is unnecessary by reason of the
cranks being opposite to each other..
[i
After leaving the low pressure cylinder C. the steam is passed through the
passage into 2 of the 3 aforesaid eduction ports e, e, into the exhaust pipe H
leading to condenser J, from which condensed steam or water, air, and uncondensed
vapour are removed by Joseph Chapman's Patent Air Extractor L. of which the
lower action sucks from condenser. J through pipe K and delivers into column B.
Column B is connected to upper action of air extractor L by means of pipe M,
and a constant vacuum is maintained in column B, the lower part of which forms
hot well from which the feed water is removed and passed to the boiler by an
ordinary feed pump,

page_text: Condenser J is formed of a pipe containing small tubes through which water
circulates either by means of the motion of the vessel, or by the action of screw
propeller, or by a special worm attached to shaft.
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:
First The general construction or arrangement of parts substantially and for
the purposes herein before described, with reference to the accompanying Drawings.
Second Controlling the admission and exhaust of steam to both the high and
low pressure cylinders by one slide valve: substantially in the manner herein
described and illustrated by the accompanying Drawings.
Dated this Seventh day of August 1884.
DANIEL ADAIR CORMACK.