IMPROVEMENTS IN THE CONSTRUCTION OF ROTARY STRAM ENGINES
Year: 1866

page_text: LETTERS PATENT to George Bell Harkes, of Eden Place, Lavender Road,
Battersea, in the County of Surrey, Engineer, for the Invention of
PROVISIONAL SPECIFICATION left by the said George Bell Harkes at
the Office of the, Commissioners of Patents, with his Petition, on the
9th August 1866..
I, GEORGE BELL. HARKES, of Eden Place, Lavender Road, Battersea, in-
the County of Surrey, Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF ROTARY STRAM ENGINES,"
to be as follows:-
This Invention consists in certain combinations and arrangements of
mechanism by the adoption of which rotary steam engines possessing great
simplicity and efficacy can be constructed; the steam cylinder is of circular:
section (but with the upper portion thereof removed as herein-after mentioned),.
and in the centre thereof is a cylinder of smaller diameter mounted on a shaft
in suitable bearings, a projection being formed on the exterior of the last-men-
tioned cylinder, such projection extending therefrom to the interior surface of
the steam cylinder, against which it is free to revolve; the said projection'
acts as 'the piston, and is furnished with any suitable packing to enable the
same to work in the interior of the steam cylinder in a steam-tight manner.
At the upper part of the steam cylinder are placed the steam port and the
exhaust port. A portion of the upper part of the steam cylinder is removed
for the admission of a block, the lower surface of which is of the form of a

page_text: segment of a circle, a casing or shell being provided for the said block to work
in. A shaft is attached eccentrically to the piston cylinder, the other end of
such shaft being attached to the segmental block. By the revolution of the
piston cylinder the segmental block is caused to oscillate through the steam
space of the steam cylinder, the lower point of the surface thereof working
against the surface of the piston cylinder between the ports, and thereby
acting as an effectual stop between the steam and exhaust ports. Upon the
steam being admitted into the steam space of the cylinder it impinges upon
the piston, and causes it to revolve until it has passed the exhaust port, when
the steam escapes; the piston moves through the small space between the
exhaust port and the steam port by means of the momentum it has acquired
aided by the action of the fly wheel attached to the engine, and having passed
the steam port the steam is again admitted, the steam space between the
steam port and the exhaust port being stopped by the before-mentioned block,
and thus a continued rotary motion is obtained, which is capable of being
imparted by means of the central shaft of the piston cylinder to any machinery
in connection therewith. As the segmental block occupies the upper portion
of the steam space of the cylinder it is manifest that it would, but for some
contrivance to obviate the difficulty, prevent the revolution of the piston upon
arriving at that portion of the steam space. To obviate this a portion of the
block is cut away so as to form a longitudinal channel extending the entire
length thereof, in which is placed a moveable block connected with arms
mounted eccentrically on each end of the piston cylinder; the said moveable
block extends the whole length of the longitudinal channel, and by means of
the before-mentioned arms rises therein as the piston approaches the upper
portion of the steam space, and thus allows it to pass through the same, and
then gradually falls until its lower surface coincides with the face of the block,
thus forming an effectual stop between the ports; the casing or shell in which
the block moves is provided with suitable packing in order that the same may
work therein without allowing any escape of steam.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said George Bell Harkes in the Great Seal Patent Office on the
9th February 1867.
TO. ALL TO. WHOM THESE PRESENTS SHALL COME, I, GEORGE
BELL HARKES, of Eden Placé, Lavender Road, Battersea, in. the County of
Surrey, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of August, in the year of our Lord 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
George Bell Harkes, Her special licence that I, the said George Bell Harkes,
my executors, administrators, and assigns, or such others as I, the said George
Bell Harkes, 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 THE
CONSTRUCTION OF ROTARY STEAM ENGINES," upon the condition (amongst others)
that I, the said George Bell Harkes, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain 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 imme-
diately after the date of the said Letters Patent..
NOW KNOW YE, that I, the said George Bell Harkes, 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 statement, reference being had to the accompanying Drawing, and
to the letters marked thereon, that is to say:-
My said Invention consists in certain combinations and arrangements of
mechanism by the adoption of which rotary steam engines possessing great
simplicity and efficacy can be constructed; the steam cylinder is of circular
section (but with the upper portion thereof removed as herein-after mentioned),
and in the centre thereof is a cylinder of smaller diameter, mounted on a shaft
in suitable bearings, a projection being formed on the exterior of the last-
mentioned cylinder, such projection extending therefrom to the interior sur-.
face of the steam cylinder against which it works during the revolution of the
smaller cylinder; the said projection acts as the piston head to receive the
pressure of the steam, and is furnished with any suitable packing to enable
the same to work in a steam-tight manner. At the upper part of the steam
cylinder are placed the steam and exhaust ports. A portion of the upper part
of the steam cylinder is removed for the admission of a block, the lower sur
face of which is of the form of the segment of a circle, a casing or shell being
provided for the said block to work in.. A shaft is attached eccentrically by
one end thereof to the exterior of the piston cylinder, the other end of such

page_text: shaft being attached to the segmental block. By the revolution of the piston
cylinder the segmental block is caused to oscillate through the steam space
of the steam cylinder, the lowest part of the surface thereof working against
the surface of the piston cylinder between the ports, and thereby acting as an
effectual stop between the steam and exhaust ports. Upon the steam being
admitted into the steam space of the cylinder it impinges upon the piston,
causing it to revolve until it has passed the exhaust port, when the steam
escapes; the piston moves through the small space between the exhaust port
and the steam port by means of the momentum it has acquired, aided when
necessary by the action of a fly wheel, and having passed the steam port the
steam is again admitted, the steam space between the steam port and the exhaust
port being stopped by the before-mentioned block, and thus a continued rotary
motion is obtained, which is capable of being imparted by means of the piston
cylinder to any machinery in connection therewith as well understood. As
the segmental block occupies the upper portion of the steam space of the
cylinder it is manifest that it would, but for some contrivance to obviate the
difficulty, prevent the revolution of the piston upon arriving at that portion of
the steam space; to remedy this a portion of the block is cut away so as to form
a longitudinal channel extending the entire length thereof, in which channel is
placed a moveable block connected with arms mounted eccentrically on each
end of the piston cylinder; the said moveable block extends the whole length
of the longitudinal channel, and by means of the before-mentioned arms rises
therein as the piston approaches the upper portion of the steam space, and
thus allows it to pass through the same, and then gradually falls until its lower
surface coincides with the face of the block, thus forming an effectual stop
between the ports; the casing or shell in which the block moves is provided
with suitable packing in order that the same may work therein without
allowing any escape of steam.
· My said Invention will be more clearly understood by reference to the
accompanying Drawing.
A, A, is the steam cylinder; B is the internal piston cylinder, the piston
being shewn in dotted lines at 6; C is the driving shaft; D, D', are
the ports; E is the segmental block; and F is the shaft connected eccen-
trically with the piston cylinder, and by which the segmental block is caused
to oscillate; G is the before-mentioned moveable block working in the lon-
gitudinal channel in the segmental block. The Drawing shews the piston
as having arrived at that portion of its revolution when it is between the
ports, the moveable block being raised to admit of its revolving without
interruption.

page_text: Having thus described and ascertained the nature of my said Invention,
and the manner in which it is to be performed, I would observe in conclusion
that what I consider novel and original, and therefore claim as constituting
the Invention secured to me by the said herein-before in part recited Letters
Patent is, the combination and arrangement of mechanism in the construction
of rotary steam engines as substantially herein-before described and set forth,
or any mere modifications thereof.
In witness whereof, I, the said George Bell Harkes, have hereunto set
my hand and seal, this Ninth day of February, in the year of our
Lord One thousand eight hundred sixty-seven.
GEORGE BELL HARKES. (LS.)
Witness,
E. P. H. VAUGHAN,
54, Chancery Lane,
Agent for the Patentee.