IMPROVEMENTS IN COMPOUND MARINE STEAM ENGINES
Year: 1881

page_text: LETTERS PATENT to Alexander Carnegie Kirk, of the Firm of Robert Napier
and Sons, of Glasgow, in the County of Lanark, North Britain, for an
Invention of IMPROVEMENTS IN COMPOUND MARINE STEAM ENGINES."
"
PROVISIONAL SPECIFICATION left by the said Alexander Carnegie Kirk at
the Office of the Commissioners of Patents on the 20th April 1881.
ALEXANDER CARNEGIE KIRK, of the Firm of Robert Napier and Sons,
of Glasgow, in the County of Lanark, North Britain. "IMPROVEMENTS IN
COMPOUND MARINE STEAM ENGINES."
This Invention relates to compound marine steam engines which are partly of the
same class as those described in a Provisional Specification filed by the present
applicant, and dated 10 February 1881 (No. 577). Whilst the modifications of engines
described in the said Provisional Specification were more especially designed for
comparatively large powers, those comprised in the present Invention are intended
for moderate powers, an important object of the new arrangements being to simplify
and otherwise improve such engines when constructed for working the steam
through three stages of expansion.
In carrying out the present Invention three cylinders are used (instead of four)
in each set of engines, and are placed vertically in some modifications. In one
modification, the first or high-pressure cylinder is placed above the second or
intermediate cylinder, the third or low-pressure cylinder being placed at the same
level as the intermediate cylinder. In a second modification, the intermediate
cylinder is placed above the low-pressure cylinder, and the high-pressure cylinder is
placed at the same level as the low-pressure cylinder. In a third modification, the
cylinders are arranged relatively to each other, as in the first modification, but are
placed horizontally; and in a fourth modification the cylinders are arranged
relatively as in the second modification, but horizontally. In all four modifications
the pistons of the three cylinders are connected to two cranks only. In any case

page_text: in which it is an object to economise space as much as possible longitudinally or
transversely, whilst the available height or vertical dimension is considerable, the
three cylinders may, according to a fifth modification, be placed one above the other,
the high-pressure cylinder being uppermost.
In any of the modifications where one cylinder is above or in line with another,
either of the covers between the cylinders may be made in two halves to be
bolted together to admit of easy removal and to give convenient access to the
cylinder.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Carnegie Kirk in the Great Seal Patent Office on the
19th October 1881.
ALEXANDER CARNEGIE KIRK, of the Firm of Robert Napier and Sons, of Glasgow,
in the County of Lanark, North Britain. "IMPROVEMENTS IN COMPOUND
MARINE STEAM ENGINES."
My said Invention relates to compound marine steam engines, which are partly
of the same class as those described in the Specification of Letters Patent granted
to me, and dated 10 February 1881 (No. 577). Whilst the modifications of engines
described in the said Specification were more especially designed for comparatively
large powers, those comprised in my present Invention are intended for moderate
powers, important objects of my new arrangements being to reduce the space
occupied in the ship longitudinally and to simplify and otherwise improve such
engines when working the steam through three stages of expansion.
In carrying out my present Invention three cylinders are used in each set of
engines and are placed vertically in some modifications, whilst in some four cylinders
are used, and in others the cylinders are placed horizontally.
And in order that my said Invention and the manner of performing the same
may be most readily understood, I will at once proceed to describe my various
modifications, with the aid of six Sheets of explanatory Drawings, which are
hereunto appended, premising that in these Drawings the same reference numerals
are used to mark the same or like parts wherever they are repeated. The general
features only of the arrangements are shown, and it is to be understood that any
parts or details which are not delineated or described are to be constructed or fitted
as in existing engines or in an analogous manner. A modification of my improved
engines is shown on each of the Sheets of Drawings.
The first of the modifications of the improved compound marine steam engines
comprised in my present Invention is shown on Sheet 1 of the accompanying
Drawings, Figure 1 being a plan, Figure 2 a side elevation, and Figure 3 an end
elevation. The engines are designed for working the steam through three stages
of expansion, and are of the inverted-cylinder class. The first or high-pressure
cylinder 21 is placed above the second or intermediate cylinder 22, a third or

page_text: low-pressure cylinder 23 being placed at the same level as the intermediate
cylinder 22.
The second modification, which is shown on Sheet 2, Figure 4 being a plan and
Figures 5 and 6 side and end elevations, is also of the inverted-cylinder class, and
in it the intermediate cylinder 22 is placed above the low-pressure cylinder 23,
whilst the high-pressure cylinder 21 is placed at the same level as the low-pressure
cylinder 23.
In the third modification, which is shown in plan and elevation in Figures 7
and 8 on Sheet 3, the cylinders 21, 22, 23, are arranged relatively to each other, as
in the first modification, but are placed horizontally.
In the fourth modification, which is shown in plan and elevation in Figures 9
and 10 on Sheet 4, the cylinders are arranged relatively to each other, as in the
second modification, but are placed horizontally.
In the modifications shown on Sheets 1 to 4, the pistons are in each case
connected to only two cranks 24, 25, the piston of the intermediate cylinder 22
being either on the same rod as that of the high-pressure cylinder 21, or on the same
rod as that of the low-pressure cylinder 23.
In the fifth modification, which is shown on Sheet 5, Figure 11 being a plan and
Figures 12 and 13 side and end elevations, there are likewise only two cranks 24, 25,
but the piston rod connected to each has on it two pistons. There are two low-
pressure cylinders 23, 23, with the high-pressure cylinder 21 above one, and the
intermediate cylinder 22 above the other, the arrangement being compact and
advantageous where a somewhat greater power is required than that conveniently
obtainable with three cylinders.
In any case in which it is an object to economise space as much as possible,
longitudinally or transversely, whilst the available height or vertical dimension is
considerable, three cylinders may, according to a sixth modification, be placed one
above the other, as shown on Sheet 6 of the Drawings. Figure 14 is a plan, and
Figures 15 and 16 are side and end elevations. The high-pressure cylinder 21 is
placed uppermost, the intermediate cylinder 22 next, and the low-pressure cylinder 23
lowermost. The three pistons are on one rod (which may consist of two or more
short lengths fixed together or to the pistons), and are connected to a single
crank 24.
In any of the modifications where one cylinder is above or in line with another,
either of the covers between the cylinders may be made in two halves to be bolted
together to admit of easy removal, and to give convenient access to the cylinder,
the upper cylinder being of course in such cases supported independently of the
lower cover. The arrangements of the valve gear, valve casings, connecting pipes
and passages, condensers, and pumps, are to some extent like those of the modifi-
cations of engines described in my earlier Specification hereinbefore referred to,
and will be easily understood from the Drawings by those acquainted with existing
constructions of marine engines; but to facilitate comprehension of the various
parts they are marked with reference numerals as follows:-High-pressure steam
inlet pipe 26; high pressure valve casing 27; pipe 28 leading steam to intermediate
valve casing 29; pipe 30 leading steam to low-pressure valve casing 31; exhaust
pipe 32 leading to condenser 33, and air and other pumps 34.
Having thus particularly described my said Invention, and the manner of
performing the same, I have to state that I do not restrict myself to the
precise details herein described or delineated, but that what I believe to be novel
and original, and claim as the Invention secured to me by and in terms of the
hereinbefore in part recited Letters Patent is,—
1. The constructing of compound marine engines so as to expand the steam
through three stages by means of three cylinders combined with two cranks, the
several parts being arranged substantially as hereinbefore described.
2. The arranging or combining together of the main parts of compound marine
steam engines, substantially in the improved manner hereinbefore described, as the
first modification.

page_text: 3. The arranging or combining together of the main parts of compound marine
steam engines, substantially in the improved manner hereinbefore described, as the
second modification.
4. The arranging or combining together of the main parts of compound marine
steam engines, substantially in the improved manner hereinbefore described, as the
third modification.
5. The arranging or combining together of the main parts of compound marine
steam engines, substantially in the improved manner herein before described, as the
fourth modification.
6. The arranging or combining together of the main parts of compound marine
steam engines, substantially in the improved manner herein before described, as the
fifth modification.
7. The arranging or combining together of the main parts of compound marine
steam engines, substantially in the improved manner herein before described, as the
sixth modification.
In witness whereof, I, the said Alexander Carnegie Kirk, have hereunto set
my hand and seal, this Fifteenth day of October, in the year of our Lord
One thousand eight hundred and eighty-one.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
ALEXANDER C. KIRK. (L.S.)