Year: 1887

page_text: Date of Application, 17th Aug., 1887.
Complete Left, 15th May, 1888
Complete Accepted, 15th June, 1888
I, JAMES HOWDEN, of 8 Scotland Street, Glasgow, in the County of Lanark, North
Britain, Engineer, do hereby declare the nature of this Invention to be as follows,
that is to say :-
My said Invention has for its object to arrange or combine the parts of triple-
expansion steam engines in an improved manner, so as to diminish waste of heat and
so as to admit of a convenient and advantageous construction and arrangement of
the crank shaft.
In carrying out my Invention the three cylinders are placed parallel and so as to
have their pistons connected to separate cranks on the shaft. The crank shaft may
consist of three equal portions each portion being either a single piece or built as may
be preferred in each case. The distance between the axes of the high-pressure and
intermediate cylinders is made by preference the same as that between the intermediate
and low-pressure cylinders. The low-pressure valve is between the low-pressure
cylinder and the intermediate cylinder; and in the necessarily larger space between
the intermediate cylinder and the high-pressure cylinders both the intermediate and the
high-pressure valves are placed. The intermediate valve is a slide valve, but the high-
pressure valve is a piston valve and is arranged to work in a valve chamber which is
entirely enclosed in the chamber between the high-pressure cylinder and the
intermediate cylinder, and which forms the valve casing to the latter. The high-
pressure steam may be admitted by a single passage into the space between the valve
pistons; and the steam may exhaust from the outer sides of the valve pistons directly
into the chamber and with direct access to the intermediate valve. Or the high-
pressure steam may be admitted by two passages to the outer ends of the piston valve
chamber and exhaust from between the valve pistons into the intermediate chamber.
Or the high-pressure steam may be admitted to one end and pass to the other end
through a tube connecting the two valve pistons.
A pair of piston valves may be used instead of a slide valve for the intermediate or
low-pressure cylinder; and an ordinary slide valve may be used instead of the high-
pressure piston valves but in the latter case it is essential to have the high-pressure
valve casing enclosed in the intermediate chamber.
2
2 JLA 1007
EDMUND HUNT,
Applicant's Agent.

page_text: COMPLETE SPECIFICATION.
Improvements in Triple-expansion Steam Engines.
1, JAMES HOWDEN, of 8 Scotland Street, Glasgow, in the County of Lanark, North
Britain, 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, that is to say :-
My said Invention has for its object to arrange or combine the parts of triple-
expansion steam engines in an improved manner, so as to diminish waste of heat and
so as to admit of a convenient and advantageous construction and arrangement of the
crank shaft.
Parts of inverted-cylinder screw-propeller steam engines are shown on two
accompanying sheets of explanatory drawings as examples of the application
of my improvements. Figure, 1, on sheet, I, of the drawings is a longitudinal
vertical section of the cylinders and valve details of a triple-expansion engine, and
figure, 2, shows the crank shaft of the same. Figure, 3, on sheet, 2, is a horizontal
section corresponding to figure, 1; and figures, 4, and 5, are tranverse vertical
sections showing modifications of valve details.
In carrying out my Invention the three cylinders, A, B, C, are placed parallel and
so as to have their pistons connected to separate cranks, D, E, F, on the shaft, G..
The crank shaft, G, may consist of three equal portions as shown each portion being
either a single piece or built as may be preferred in each case. The distance between
the axes of the high-pressure and intermediate cylinders, A, B, is made by preference
the same as that between the intermediate and low-pressure cylinders, B, C. The low-
pressure valve, H, is between the low-pressure cylinder, C, and the intermediate
cylinder, B, and in the necessarily larger space between the intermediate cylinder, B,
and the high-pressure cylinder, A, both the intermediate and the high-pressure
valves, J, K, are placed. The intermediate valve, J, is a slide valve, but the high-
pressure valve, K, is a piston valve and is arranged to work in a valve chamber, L,
which is entirely enclosed in the chamber, M, between the high-pressure cylinder, A,
and the intermediate cylinder, B, and which forms the valve casing to the latter.
The high-pressure steam may be admitted by a single passage, N, into the space
between the valve pistons, P, as shown in figures, 1, and 3, and the steam may
exhaust from the outer sides of the valve pistons directly into the chamber, M, and
with direct access to the intermediate valve, J. Or the high-pressure steam may be
admitted by two passages, Q, as shown in figure, 4, to the outer ends of the piston-
valve chamber, L, and exhaust from between the valve pistons into the intermediate
chamber, M. Or the high-pressure steam may be admitted to one end and pass to
the other end through a tube, R, connecting the two valve pistons, P, as shown in
figure, 5.
A pair of piston valves may be used instead of a slide valve (J) for the intermediate
or low-pressure cylinder; and an ordinary slide valve may be used instead of the
high-pressure piston valves, P, but in the latter case it is essential to have the high-
pressure valve casing, L, enclosed in the intermediate chamber, M.

page_text: One practical advantage of the hereinbefore described arrangement of cylinders and
valve casings consists in being able to place the various eccentrics, S, for
working the valves, on the bodies of the portions of crank shaft, G, instead of on the
couplings, T.
Having now particularly described and ascertained the nature of my said Inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a triple-expansion steam engine having three cylinders in connection with three
cranks, placing the cylinders with their axes at about equal distances apart with the low-
pressure valve chamber between the low-pressure and intermediate cylinders and the
intermediate valve chamber between the intermediate and high-pressure cylinders and
with the high-pressure valve casing within the intermediate valve chamber substantially
as herein before described.
2. Arranging or combining parts of triple-expansion steam engines substantially as
hereinbefore described with reference to figures, 1, 2, 3, of the accompanying drawings
or with modifications described with reference to figures, 4, and 5.
Dated thin Flourouth low of Man 1000
EDMUND HUNT,
Applicant's Agent.