IMPROVEMENTS IN MARINE STEAM ENGINES
Year: 1866

page_text: LETTERS PATENT to John Elder, of Glasgow, in the County of Lanark,
North Britain, Engineer, for the Invention of "IMPROVEMENTS IN MARINE
STEAM ENGINES."
Sealed the 5th January 1867, and dated the 9th July 1866.
PROVISIONAL SPECIFICATION left by the said John Elder at the
Office of the Commissioners of Patents, with his Petition, on the
9th July 1866.
I, JOHN ELDER, of Glasgow, in the County of Lanark, North Britain,
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN MARINE STEAM ENGINES," to be as follows:-
This Invention has for its object to combine economy of fuel with simplicity
and moderate first cost in marine steam engines, and the improvements are
carried into effect in two modifications or general designs herein-after
described.
The economy in fuel is obtained by arranging the engines to be worked on
the double cylinder expansion system, whilst diminished first cost of the
engines is secured, together with general simplicity and convenience, by
making them with only two cylinders, a single high-pressure one, and a single
low-pressure one, the large low-pressure cylinder being fixed and being fitted
with piston rod, slide blocks, guides and connecting rod, whilst the small high-
pressure cylinder is arranged to oscillate and has its piston rod jointed directly
upon the same crank pin as the connecting rod of the other cylinder. The
bigh-pressure cylinder is arranged to act on the crank in a direction making

page_text: a convenient angle with the direction of action of the low-pressure cylinder.
Both cylinders with their covers or ends are steam-jacketed, and they are both
provided with ordinary slide or other convenient valves, the low-pressure
cylinder having by preference, a cut-off valve in addition. The steam on
leaving the high-pressure cylinder enters an intermediate receiver, which may
be simply an enlarged passage between the cylinders, or more or less of it
may constitute an outer jacket space surrounding the high-pressure cylinder
or the low-pressure cylinder, or both. Or the steam after acting in the high-
pressure cylinder may be conveyed by suitable pipes to a compartment or
section of the boiler to be reheated or superheated before entering the low-
pressure cylinder.
In one modification of the improved engines suitable for driving paddle
wheels the oscillating high-pressure cylinder is disposed directly under the
crank shaft, whilst the large low-pressure cylinder is placed in an inclined
position at one end of the bed frame, this frame assuming a comparatively
long narrow form. The surface or other condenser and the various pumps
can be very conveniently arranged between the two cylinders, and the whole
forms a very compact design, but with every part freely accessible.
In another modification suitable for paddle engines or for geared screw
engines the fixed low-pressure cylinder is disposed directly under the crank
shaft, being fitted with two or four piston rods, and with a return connecting
rod like what is known as the "steeple " engine, whilst the oscillating high-
pressure cylinder is placed towards one end or side and at an elevation suitable
for its acting on the crank at a convenient angle. The surface or other con-
denser is conveniently arranged beneath the oscillating cylinder, and the
various pumps may be worked by levers or by eccentrics on the crank shaft,
and they may be disposed on each side of the condenser or on the other side
of the low-pressure cylinder,
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Elder in the Great Seal Patent Office on the 9th 3
January 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
ELDER, of Glasgow, in the County of Lanark, North Britain, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters 3.
Patent, bearing date the Ninth day of July, in the year of our Lord

page_text: One thousand eight hundred and sixty-six, in the thirtieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the
said John Elder, Her special licence that I, the said John Elder, my
executors, administrators, and assigns, or such others as I, the said John
Elder, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN MARINE STEAM
ENGINES," upon the condition (amongst others) that I, the said John Elder,
my executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and ascer-
tain the nature of the said Invention, and in what manner the same was to
be performed, and cause the same to be filed in the Great Seal Patent Office
within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said John Elder, do hereby declare the
nature of my said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following state-
ment in writing, reference being had to the accompanying Drawings, that is
to say :-
My said Invention lias for its object to combine economy of fuel with
simplicity and moderate first cost in marine steam engines, and my improve-
ments are carried into effect in two modifications or general designs, each of
which is susceptible of variation as regards its minor details.
And in order that my said Invention and the manner of performing the
same may be properly understood, I have hereunto appended two Sheets of
explanatory Drawings, to be herein-after referred to, and representing marine
engines embodying my improved arrangements.
An example of one of my improved general designs is represented on
Sheet 1 of the Drawings, Figures 1 and 2 being longitudinal and transverse
vertical sections, whilst Figure 3 is a section, partly as in the horizontal plane
and partly as in an inclined plane. Figure 4 is a section of the air and
circulating pumps.
On Sheet 2 of the Drawings two examples are shown of my other improved
general design, Figures 5 and 6 being a plan and vertical section of one
example, and Figures 7 and 8 a plan and sectional elevation of the other.
The two general designs possess several features in common.
The economy
in fuel is obtained by arranging the engines to be worked on the double-

page_text: cylinder expansion system; whilst diminished first cost of the engines is
secured, together with general simplicity and convenience by making them in.
each case with only two cylinders, a single high-pressure one H, and a single
low-pressure one L, the large low-pressure, cylinder L being fixed and being
fitted with piston rod 1, slide blocks 2, guides 3, and connecting rod 4, whilst
the small high-pressure cylinder H is arranged to oscillate on trunnions 5,
and has its piston rod 6 jointed directly upon the same crank pin 7, as the
connecting rod 4 of the other cylinder L.
In Figures 7 and 8, Sheet 2, the engines are represented as arranged for
driving twin screw shafts 8, 9, independently, and consequently comprise two
distinct sets of the parts herein-before referred to. The high-pressure
cylinder His in all the modifications arranged to act on the crank 7, in a
direction making a convenient angle with the direction of action of the low-
pressure cylinder L. Both cylinders H, L, with their covers or ends are
steam-jacketed, and they are both provided with ordinary slide or other con-
venient valves, the low-pressure cylinder L having by preference a cut-off valve.
in addition. The steam on leaving the high-pressure cylinder H enters an
intermediate receiver, which may be simply an enlarged passage between the
cylinders Hand L, or more or less of it may constitute an outer jacket space
surrounding the high-pressure cylinder H, or the low pressure cylinder L, or
both; or the steam after acting in the high-pressure cylinder H may be
conveyed by suitable pipes to a compartment or section of the boilers to be
reheated or superheated before entering the low-pressure cylinder L.
As the arrangements for dealing with the steam between the two cylinders
may thus be effected in various ways, and as engineers are well acquainted
therewith, I have considered it unnecessary to show any special modification
thereof on the accompanying Drawings; various other details are also omitted
in the Drawings, their construction and adaptation being identical with or
analogous to those of the corresponding details in well-known engines.
In one modification of my improved engines, namely, that represented on
Sheet1 of the accompanying Drawings, and which is suitable for driving
paddle wheels, the oscillating high-pressure cylinder H is disposed directly
under the crank shaft 9, whilst the low-pressure cylinder L is placed in an
inclined position at one end of the bed frame 10; this frame assuming a
comparatively long narrow form. The surface or other condenser 11, and the
various pumps 12, are very conveniently arranged between the two cylinders
H, L, and the whole forms a very compact design but with every part freely
accessible.
The other modification of my improved engines is suitable for paddle

page_text: engines or for geared screw engines, as in the example shown at Figures 5
and 6, on Sheet 2 of the accompanying Drawings; or for directly driving twin
screws, as in the example shewn in Figures 7 and 8. When two short-
stroked cylinders are arranged as in Figures 7 and 8, they may obviously be
employed for driving a single screw directly. In this modification the fixed
low-pressure cylinder L is in each case disposed directly under the crank shaft 9,
being fitted with two or four piston rods 1, and a return connecting rod 4,
like what is known as the "steeple" engine; whilst the oscillating high-
pressure cylinder is placed towards one end or side and at an elevation suitable
for its acting on the crank 7 at a convenient angle. The surface or other
condenser 11 is conveniently arranged beneath the oscillating cylinder H, and
the various pumps 12 may be worked by levers or by eccentrics on the crank
shaft 9, and they may be disposed on each side of the condenser or on one
side of the low-pressure cylinder L.
In the arrangement shown in Figures 7 and 8, the frames 13, containing
the guides 3 and crank shaft bearings are supported upon the large low-
pressure cylinders L, the strain between the bearings and cylinders being
transmitted by blocks 14, which can be removed without disturbing the
frames 13, when it may be necessary to take off the cylinder covers. There
are also four pillars 15 to bear the mere weight of the frames 13, and one of
these is made removable to permit of the withdrawal of the cylinder cover.
Having thus particularly described my said Invention, and the manner in
which the same is to be performed, 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
the herein-before in part recited Letters Patent is, the constructing of a set
of marine engines with an oscillating high-pressure cylinder combined with a
fixed low-pressure cylinder, and both acting on the same crank pin, but in
different directions, substantially as herein-before described.
In witness whereof, I, the said John Elder, have hereunto set my hand
and seal, this Second day of January, in the year of our Lord One
thousand eight hundred and sixty-seven.
JOHN ELDER. (L.S.)