IMPROVEMENTS IN ROTARY ENGINES
Year: 1863

page_text: LETTERS PATENT to Cyrus Avery, of Philadelphia, Pennsylvania, United
States, now residing at No. 39, Craven Street, Strand, in the County of
Middlesex, for the Invention of "IMPROVEMENTS IN ROTARY ENGINES."
Sealed the 21st December 1863, and dated the 29th June 1863.
PROVISIONAL SPECIFICATION left by the said Cyrus Avery at the
Office of the Commissioners of Patents, with his Petition, on the 29th
June 1868.
I, CYRUS AVERY, of Philadelphia, Pennsylvania, United States, now
residing at No. 39, Craven Street, Strand, in the County of Middlesex, do
hereby declare the nature of said Invention for "IMPROVEMENTS IN ROTARY.
ENGINES," to be as follows:-
The nature of said Invention consists in the peculiar formation and arrange-
ment of the parts of a rotary engine, whereby is secured simplicity and
cheapness of construction, and efficiency and economy in operation. The bed
plate is constructed of any suitable material and convenient form. Near one
side of this plate is fixed vertically a case, which answers the purpose of
confining the steam as it escapes from the cylinder, and at the same time
forming a double bearing for one of the driving shaft. Near the opposite

page_text: side of this plate is fixed the bearing for the other end of the shaft. For
convenience the said case is made of a circular form and of two separate
pieces or halves. The circular cylinder employed fits loosely in the case, and
is also constructed of two similar pieces or halves. In forming the cylinder, a
space is left between these pieces, extending from the inside of the steam
chamber to the exterior of the cylinder. In this space is an annular plate,
which extends from the outside of the steam chamber to a point beyond the
steam cylinder, and is fixed by screws to projections on the circumferance of
the cylinder case. This plate is cut away sufficiently through a part of its
interior circumferance to form an aperture for the escape of steam from the
chamber into the case. Upon the interior of annular plate is attached
the piston that fits the circular steam chamber, a passage being made through
the annular plate and piston to admit the steam into the said chamber. Two
or more slide valves, extending from nearly the centre on one side of the
circular steam chamber to about the centre of this chamber upon the opposite
side, are employed. These valves are successively thrown across the steam
chamber as they pass the piston, by means of a cam or friction roller, con-
fining thereby the steam in the chamber between the piston and the valve thus
thrown across, till the latter has revolved to the aperture made for the escape
of the steam.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Cyrus Avery in the Great Seal Patent Office on the 29th
December 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CYRUS
AVERY, of Philadelphia, United States, now residing at No. 39, Craven Street,
Strand, in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of June, in the year of our
Lord One thousand eight hundred and sixty-three, in the twenty-seventh
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Cyrus Avery, Her special license that I, the said
Cyrus Avery, my executors, administrators, and assigns, or such others as I,
the said Cyrus Avery, my executors, administrators, or assigns, should at any
time agree with, and no others, from time to time and all times there--
after during the term therein. expressed, should and lawfully might make,

page_text: use, exercise,. and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN ROTARY ENGINES," upon the condition (amongst others) that I, the
said Cyrus Avery, my executors or administrators, by an instrument in writing
under my hand and seal, or under the hand and seal of one of them, 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 Cyrus Avery, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the accompanying Sheet of Drawings,
making a part of this Specification..
The nature of my Invention consists in the peculiar formation and arrange-
ment of the parts of a rotary engine, whereby is secured simplicity and
cheapness of construction with efficiency and economy of operation. By my
form of construction and arrangement of the working parts the friction is

page_text: the shell or case, and is constructed in two pieces or halves. This plate
is let in between the two flanges of the shell, and should be constructed of
hardened steel. An enlargement of this plate at one point forms a part of
the piston.
About one-half of the said plate is cut away even with the inside of the
shell or case, which allows the steam to exhaust or escape from the cylinder
into the steam chamber. G, Figure 3, is the piston of the engine, of about
the same length as diameter, made solid or for packing rings. Through the
centre of the piston is an aperture to admit the passage of the steam from the
boiler, by means of the steam pipe I, Figures 2 and 3. H is the back part of
the cylinder secured to the shaft E. The front of the cylinder is nearly the
counterpart of the back, and the two parts are bolted together, with a thin
packing between them that can be removed at pleasure to tighten up against
the piston G, and the circular plate F. J, J, are two valves, extending from
the steam chamber on one side through the same on the opposite side, for
the purpose of closing up the passage in said chamber. These valves cross
each other at right angles, and are successively thrown across the steam
chamber as they pass the piston G, by means of the friction roller L, and the
cams K, K. These cams may be either let into the inside of the steam
chamber, or in the outside of the said chamber, and worked inward by means
of a crooked groove. These cams K, K, are firmly fixed to the valves J, J,
and are set on an angle in order that they may throw the valves across the
steam chamber as they pass under the roller L, confining thereby the steam
in the chamber between the piston G and the valve thus thrown across, till
the latter has revolved to the aperture made in the circular plate for the
purpose of its escape. This roller is bolted to the portion of the shell C, and
is oiled from the outside through the journal or shaft. The operation of this
engine will be readily understood from the foregoing description of the parts.
The pressure of the steam in the cylinder, between the piston G and the
valves J, J, successively gives force and motion to the cylinder H and the
shaft E.
Any suitable material may be employed in the construction of the engines,
though cast iron for most of the parts is found suitable and economical.
They may be made of any required power by increasing the size, and both
the form and arrangement of the parts may be considerably modified, without
departing from the spirit of my Invention.
Having thus described my improvements, I wish it understood that I do
not confine myself to the exact details set forth; but I claim as my Invention

page_text: the circular plate F, the valves J, J, the stationary piston G or its equivalent,
constructed and combined substantially as described.
In witness whereof, I, the said Cyrus Avery, have hereunto set my hand
and seal, this Eleventh day of December, in the year of our Lord
One thousand eight hundred and sixty-three.