IMPROVEMENTS IN MOTIVE-POWER ENGINES
Year: 1864

page_text: LETTERS PATENT, to James Young; of 19, Bucklersbury, in the City of
London, Gentleman, and Alexander Carnegie Kirk, of Bathgate, in, the
County of, Linlithgow, North Britain, Engineer, for the Invention of
"IMPROVEMENTS IN MOTIVE-POWER ENGINES."
PROVISIONAL SPECIFICATION. left by the said James Young and
Alexander Carnegie Kirk at the Office of the Commissioners of Patents,
with their Petition, on the 27th January 1864.
We, JAMES YOUNG, of 19, Bucklersbury, in the City of London, Gentleman,
and 'ALEXANDER CARNEGIE KIRK; of Bathgate, in the County of Linlithgow,
North Britain; Engineer, do hereby declare the nature of our said Invention
for "IMPROVEMENTS IN MOTIVE-POWER ENGINES," to be as follows:-
This Invention relates to a mode of heating the air in that description of
motive-power engines in which mechanical power for moving any kind of
machinery is produced by causing air or other elastic fluid to be expanded by
heat, and consists in heating the air or other elastic fluid whilst being used in
such engines by exposing it to the surface of vessels or tubes heated by steam,
such vessels or tubes communicating with a steam boiler, and containing steam
under a pressure sufficient to maintain the desired temperature. The water
produced by the condensation of the steam in these vessels or tubes is either
returned to the boiler or allowed to escape:

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Young and Alexander Carnegie Kirk in the Great
Seal Patent Office, on the 23rd July 1864.
'
TO ALL TO WHOM THESE PRESENTS SHALL, COME, we, JAMES
YOUNG, of 19, Bucklersbury, in the City of London, Gentleman, and
ALEXANDER CARNEGIE KIRK, of Bathgate, in the County of Linlithgow, North
Britain, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of January, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
us, the said James Young and Alexander Carnegie Kirk, Her special license
that we, the said James Young and Alexander Carnegie Kirk, our executors,
administrators, and assigns, or such others as we, the said James Young and
Alexander Carnegie Kirk, our exécutors, administrators, or assigns, should at
any time agree with, and no others, from time to time and at all times there-
after 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 MOTIVE-POWER ENGINES," upon the condition (amongst others) that we, the
said James Young and Alexander Carnegie Kirk, our executors or adminis-
trators, by an instrument in writing under our hands and seals, or under the
hand and seal of one of us or them, 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 we, the said James Young and Alexander
Carnegie Kirk, do hereby declare the nature of our said Invention, and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement, reference being had to. the
accompanying Drawings, and to the letters and figures marked thereon, that
is to say:-
Our said Invention relates to a mode of beating the air in that description
of motive-power engines in which mechanical power for moving any kind of
machinery is produced by causing air or other elastic. fluid to be expanded by
heat, and consists in heating the air or other elastic fluid whilst being used in
such engines by exposing it to the surface of vessels or tubes heated by steam,
A

page_text: such vessels or tubes communicating with a steam boiler, and containing
steam under a pressure sufficient to maintain the desired temperature... The
water produced by the condensation of steam in these vessels or tubes is either
returned to the boiler or allowed to escape.
In applying our said. Invention to the various kinds and forms of air
engines, the shape, size, and arrangement of these heating tubes or vessels
may be greatly varied, care being taken that the condensed water be nowhere
allowed to accumulate in any part of the tubes or vessels, but be caused to
drain off constantly to some part convenient for its discharge.
And in order that our said Invention may be fully understood, we shall
now proceed more particularly to describe the same, and for that purpose
we shall refer to the several Figures on the Sheet of Drawings bereunto
annexed, the same letters of reference indicating corresponding parts in all the
Figures..
These Drawings illustrate two examples of the mode of applying our
improvements to the description of air engine known as "Stirling's air
engine," in which an enclosed quantity of air is caused alternately to expand
and contract in volume by being shifted by a displacing piston alternately
from a heated to a cooled end of the enclosing cylinder, and vice versa.
Fig. 1. is a side elevation of a complete engine, and Fig. 2 is a transverse
vertical section of the same taken through one of the displacing pistons and
its cylinder; A, A, are the displacing cylinders, the upper ends of which are
the hot or expansion ends, and the lower the cool or contraction ends.. As is
usual in such engines, the displacing pistons B are worked by a lever C,
actuated by another lever. D and eccentric E on the main or crank shaft F.
Each cylinder also communicates as usual with one end of the working
cylinder G, containing a piston by which, through the medium of a piston
rod H, connecting rod I, and crank K, the alternate expansion, and con-
traction of the enclosed air will cause the crank shaft. F to revolve in the
direction of the arrow. The lower part of the cylinders A is, as usual in such
engines, kept cool by a stream of cold water which enters by the pipe L and
flows through the circular grooves M, M, in succession and passes off', by the
pipe N, the air being allowed to escape by the small vent pipes O. The
displacing piston B, which fits pretty nearly the corrugations at the top and
bottom of the cylinder A, has holes in it to allow the air a free passage.
through the usual regenerator P contained in the displacing piston.
The arrangement by which our improved method of heating the working
air in an air engine of the kind above referred to consists of a vessel or
steam. jacket. Q (capable of containing steam at a sufficient temperature)

page_text: formed on the top or hot end of each displacing cylinder A. The steam
enters this vessel by the pipe R, and in heating the air contained in the
cylinder is condensed on the upper surface of the plate. S, and flows into the
groove T (which extends as a free passage all round); from which the water
of condensation escapes by the pipe U, and may, if desired, be returned
to the boiler. To increase the beating surface in contact with the, air
the under side of the plate S-is shewn as corrugated or covered with annular
ridges.
.
.:
Fig. 3 of our Drawings is a section of a displacing cylinder A. and piston.B;
wherein, according to another well-known arrangement, the piston is filled with
a non-conducting material, and the air allowed to pass from the one end of..the
cylinder to the other by a passage or pipe W connecting the top and bottom
ends of the cylinder. The passage X (shewn also in Fig. 2) forms the com-
munication with the working cylinder, which is not shown in Fig. 3.. The
lower part of the communication between the two ends of the cylinder. A is
formed of a number of small tubes Y, through which the air' passes, such
tubes being fixed air-tight in each end of the circular vessel or chamber Z,
and the cooling of the air is effected by causing a current of cold water to
circulate through the vessel or chamber Z outside the tubes, and also through
the bottom cover a of the cylinder A, which is made hollow for that purpose,
the water entering by the pipes L and flowing off by the pipes N; P is the
regenerator, placed as.usual between the hot and cold ends of the displacing
'cylinder A.
:
The arrangement for heating the working air of an air engine consists in
forming part of the passage connecting the top and bottom of the displacing
cylinder A of a number of small tubes 6, through which the air passes, such
tubes being contained in and fixed air-tight into the ends of the cylinder or
chamber c. The upper end of the displacing cylinder A is also surrounded
by a vessel or steam jacket Q. Steam of sufficient temperature enters the
chambers c and Q (which are to be made sufficiently strong to resist the
pressure of the steam) by the pipes R, R', and flows off after condensation
by the pipes U, U', whence it may be either discharged or returned to the
boiler.
.
In some arrangements of air engines we find it is more convenient to have
the steam inside a series of pipes or a coil or coils of pipe, and the outer
surface of the pipes exposed to the working air. It will sometimes be found
convenient to increase the heating surface exposed to the air by causing the
surface of the tubes to be formed with grooves in a longitudinal, circular, or
spiral direction; and it will sometimes, for the same purpose, be found con-

page_text: venient to roughen the surface by forming it into small projections or teeth
somewhat like teeth of a file. To prevent waste of heat the vessels or pipes
containing steam ought to be protected by some non-conducting material.
We would observe, in conclusion, that we lay no claim to the heating of
air or other elastic fluids by exposing such fluids to the surface of vessels or
tubes containing steam when not applied to motive-power air engines;
neither do we claim the special forms and arrangements of air engines above
described, these being already well known; but what we consider to be novel
and original, and therefore claim as the Invention secured to us by the
herein-before in part recited Letters Patent, is,
First, the system or mode of heating the air or other elastic fluid employed
in that description of motive-power engines known as hot-air engines, by
exposing such air.or other elastic fluid to the surface or surfaces of vessels or
tubes heated by steam, provision being made for allowing the water formed
by the condensation of the steam either to escape or to be returned to the
boiler, substantially as herein-before described.
Second, the application and use to and in hot air motive-power engines of
the peculiar arrangement of apparatus for heating the air or other elastic
fluid employed therein, as herein-before described and illustrated by our
Drawings.
In witness whereof, I, the said Alexander Carnegie Kirk, on behalf of
myself and the said James Young, have hereunto set my hand and
seal, the Twenty-first day of July One thousand eight hundred and
sixty-four.
ALEXANDER CARNEGIE KIRK. (L.S.)