IMPROVEMENTS IN MARINE- ENGINES
Year: 1882

page_text: LETTERS PATENT to George Alexander Philips Haldane Duncan, of the Firm
of Messrs. Maudslay, Sons, and Field, of 110, Westminster Bridge Road, in
the County of Surrey, for an Invention of "IMPROVEMENTS IN MARINE-
ENGINES"
PROVISIONAL SPECIFICATION left by the said George Alexander Philips
Haldane Duncan at the Office of the Commissioners of Patents on the
17th February 1882.
GEORGE ALEXANDER PHILIPS HALDANE DUNCAN of the Firm of Messrs.
Maudslay Sons and Field of 110 Westminster Bridge Road in the County of
Surrey. "IMPROVEMENTS IN MARINE ENGINES."
My Invention relates to an arrangement of compound marine engines and of
their connecting channels and valves in such a manner that the working power can
be varied over a wide range without materially interfering with the regularity of
action. For this purpose I arrange four cylinders in a row, the first and last of the
row being of large size and provided with condensers and air pumps to work as
condensing engines. The second and third cylinders of the row are considerably
smaller and adapted for working at bigh pressure without condensation. The pistons
of all the cylinders are connected to cranks on one shaft. It is convenient to
arrange the cranks for the first second and third cylinders at about 120° to one
another, and the crank for the fourth opposite to that for the first, but the setting
of the cranks may be varied. The steam and discharge channels are provided with
valves which can be set by hand so as to work the engines in several different ways,
for example the second and first cylinders may be worked together as a compound
engine, the exhaust from the second expanding in the first, and the third and fourth
may be worked together in like manner. Either of those pairs may be worked alone
or along with the other pair. Again, the second and third cylinders may be worked
along with the first as a compound engine, the exhaust from both the second and
third expanding in the first; and in like manner the second and third may be
worked along with the fourth. In this manner the power and speed of the
engines can be readily varied and facilities are given for repairs and adjustments.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said George Alexander Philips Haldane Duncan in the Great Seal
Patent Office on the 5th August 1882.
GEORGE ALEXANDER PHILIPS HALDANE DUNCAN of the Firm of Messrs.
Maudslay Sons and Field of 110 Westminster Bridge Road in the County of
Surrey. "IMPROVEMENTS IN MARINE ENGINES."
My Invention relates to an arrangement of compound marine engines and of
their connecting channels and valves in such a manner that the working power
can be varied over a wide range without materially interfering with the regularity
of action. For this purpose I arrange four cylinders in a row, the first and last of
the row being of large size and provided with condensers and air pumps to work
as condensing engines. The second and third cylinders of the row are considerably
smaller and adapted for working at high pressure without condensation. The
pistons of all the cylinders are connected to cranks on one shaft. It is convenient
to arrange the cranks for the first, second and third cylinders at about 120° to one
another, and the crank for the fourth opposite to that for the first, but the setting
of the cranks may be varied. The steam and discharge channels are provided with
valves which can be set by hand so as to work the engines in several different ways,
for example, the second and first cylinders may be worked together as a compound
engine the exhaust from the second expanding in the first, and the third and fourth
may be worked together in like manner. Either of those pairs may be worked
alone or along with the other pair. Again, the second and third cylinders may be
worked along with the first as a compound engine, the exhaust from the second
and third expanding in the first; and in like manner the second and third may be
worked along with the fourth. In this manner the power and speed of the engines
can be readily varied and facilities are given for repairs and adjustments.
Fig 1 of the accompanying Drawings is a diagrammatic elevation of a four
cylinder compound engine arranged according to my Invention. Fig 2 is a
diagrammatic plan, and Fig 3 a diagram shewing the arrangement of the four
cranks C¹ C² C³ C for the four cylinders A¹ A'A³ A' respectively, of which A² and
As are high pressure cylinders, and A² A, are low pressure cylinders worked by
the exhaust steam A² or A³ or of both. S is the pipe supplying steam which by
means of the valves V1 V2 can be directed to either of the cylinders A³ A³ or to
both. A line of exhaust pipe E forms a communication from the discharge
passages of both the cylinders A' A³ to supply the cylinders A' A, either of which
can be cut off from communication by the valves D¹ D³. By closing a central
valve D³, the two cylinders A' A³ or the two cylinders A³ A' can work as a
compound engine, or both pairs can be made to work as a pair of compound engines.
The steam after expanding and performing work in either or both the cylinders A' A'
flows by the pipes B¹ B to the condensers F¹ F². In Fig 3 the cranks C₁ C² Cs are
shewn at 120° to each other and C' opposite to C¹ in which position it balances C¹.
The crank C' might however occupy another position, and the other cranks need
not be at 120° to one another strictly.
Having thus described the nature of my Invention and in what manner the same
is to be performed, I claim :-
The herein described arrangement of four cylinder compound engine with
suitable valves admitting of two of the cylinders being worked as a single

page_text: compound engine, or of three of them being so worked, or of all four being
worked as a pair of compound engines, substantially as and for the purposes herein
set forth.
In witness whereof I the said George Alexander Philips Haldane Duncan have
hereunto set my hand and seal this First day of August in the year of our
Lord One thousand eight hundred and eighty two.
GEORGE ALEXANDER PHILIPS HALDANE DUNCAN. (L.S.)