IMPROVEMENTS IN ROTARY ENGINES
Year: 1847

page_text: year of
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, STEPHEN
R. PARKHURST, of Leeds, in the County of York, Manufacturer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Fourteenth day of
January (One thousand eight hundred and forty-seven), in the tenth
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Stephen R. Parkhurst, my exors, adññors, and assigns, Her especial
licence, full power, sole privilege and authority, that I, the said Stephen R.
Parkhurst, my exors, adññiors, and assigns, or such others as I, the said
Stephen R. Parkhurst, my exors, adiñors, or assigns, should at any time agree
with, and no others, from time to time and at all times during the term of
years therein expressed, should and lawfully might make, use, exercise, and vend,
within England, Wales, and the Town of Berwick-upon-Tweed, my Invention
of "IMPROVEMENTS IN ROTARY ENGINES;" in which Letters Patent is contained
a proviso that I, the said Stephen R. Parkhurst, should cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, by an instrument in writing under my hand and seal, to
be inrolled in Her said Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said in part recited Letters
Patent, as in and by the same, reference being thereunto bad, will more fully
and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Stephen R. Parkhurst, do hereby declare that the nature of my said Invention,

page_text: and the manner in which the same is to be performed, are fully described
and ascertained in and by the following statement thereof, reference being had
to the annexed Drawings, that is to say :-
The intent of these improvements is, that steam or other elastic or non-
elastic fluids of any competent pressure shall pass into one side of a cylinder
or metal vessel made not quite as a true circle, and passing round in contact
with a portion of the interior surface, shall force a succession of flat pistons
or piston valves in the same line of direction with the propelling fluid, until
the fluid passes out either direct into the air or a condenser, or is led into and
operates in and through one, two, or more additional cylinders, of the same
character as the first cylinder, thus using the same steam or other fluid suc-
cessively to communicate motion to several sets of flat pistons or piston valves,
until the final escape of the steam or fluid in either of the modes above
specified. In any of these cases the flat pistons or piston valves are to be
set to act in and within the outer face of a true cylinder, set eccentrically
within the exterior cylinder, and having within it stuffing boxes, by which rods
from the piston valves shall be connected with and adjusted to a shaft set
eccentrically with both the interior and exterior cylinders, so that the shaft
rotating with the valves and inner cylinder shall communicate the motive
power of the steam or other fluid to any machinery with which it may be
connected. The covers at each end of the interior cylinder are formed as
annular disks, whose outer edges revolve under an auxiliary and unequal
annular ring fixed on the edges of the exterior and eccentric cylinder, and
the parralelism of these motions is maintained by a short cylinder on the inner
edges of the inner cylinder cover at each end, revolving in contact with a set
of fixed guide wheels or rollers. The constructive manner in which these
several parts act to effect these motions and ends are shewn in the Drawing
annexed hereto, and forming part of this descriptive Specification. In this,
the lower and main, Fig. 1 is an open plan, with the covers removed to shew
the interior parts of one rotary engine constructed according to this improved
plan; the other part of the same, Fig. 1 shows a corresponding rotary engine
connected with the first, but with the covers in place on the ends of the
cylinders, and the guide wheels adjusted in contact with the work.
The upper, or Fig. 2, is a vertical sectional elevation applicable to either
of the rotary engines shewn in Fig. 1. It is not material that the machine
should be used as shewn, as the parts may be used either vertically or horizon-
tally. The same letters and numbers, as marks of reference, apply to the like
parts in each Fig. a is the main shaft, having a ring joint 1, that is fitted
with three short equilateral arms 6 61, 62; the outer ends of these are fitted

page_text: with nuts 6 3, having right and left handed threads within them, through
which the piston rods 64, 65, 66, are at the same time connected to and
adjusted with the shaft a; the piston rods pass into three stuffing boxes b 7,
on the inside of the internal ring cylinder 68; these stuffing boxes are so
made, that between their inner and outer ends the piston rods can be jointed
to and draw in and force out the three flat pistons or piston valves 69, as the
rotation progresses by the internal action of the steam or other fluid; c is the
top cover between the inner and outer cylinders, and cl is the bottom or
opposite cover, both made as annular and equal disks with short cylinders c 2,
on their inner edges, and the outer surface of each of these covers is made to
form a A rib 2, close to the outer edge, all cast or otherwise formed together,
which rib 2 enters a similar circular groove in c 3; c 4, two flat cover rings
made as shewn in the right hand or covered part of Fig. 1, with one side
wider than the other; the edges of these covers are secured to the ends of the
exterior unequal cylinder A, of which the steam side c 5 is made from the
centre of the shaft a; the vacuum side c 6 is made eccentric to the steam
side. c7 are connecting steam pipes between each two engines; c 8 are
induction steam pipes, and c 9 are eduction steam pipes. 3 are steam stops
on the inside of the cylinder A. d, are three pairs of equilateral bearings
round the cylinder A, to carry the upper and lower ends of the shafts e, each
of which are fitted at each end with a roller wheel f, thus forming three
pairs of guide rollers, acting on the outsides of the short cylinders c 2, to keep
them and the covers, valves, and piston rods in the correct position for carrying
round the shaft a, when steam or other fluid is admitted under pressure to
pass on either side into the steam side c5, of the cylinder A, and act in
succession on the pistons 6 9. No cocks or valves are shewn herein as
fitted to the steam pipes or the induction and eduction pipes, as these can
be fitted in any usual manner, and may be regulated to give the rotary motion
of the interior cylinder and the valve pistons in either direction, as required
for any given purpose. In some cases the large guide wheels f may be dis-
pensed with by substituting boxes with slides or rollers, or any equally effec-
tive device, secured and adjusted on the cover rings c 3, c 4, to act around the
short cylinders c 2, and keep the parts properly in place for action.
This Invention and arrangement of rotary engines was originally designed
by me to be applied to and combined with my Invention of a method of pro-
pelling vessels, for which Her Majesty's Royal Letters Patent for England
and Wales, &c., were issued to me on the Seventeenth day of November, One
thousand eight hundred and forty-five; but these Improvements in Rotary
Engines are equally available for use in giving motion to any other description

page_text: of machinery; therefore, I do not herein restrict the employment of this
Invention, but intend to employ the saine for any purpose whatever to which
it may be applicable.
What I claim as new and of my own Invention, and desire to secure by
Letters Patent, is, the application of the right and left handed screw nuts b 3,
to connect and adjust the piston rods and piston valves with the main shaft;
the arrangement of the parts by which the piston rods and valves are con-
nected; the mode described of mounting and fitting the annular disks that
form the covers with short cylinders and roller guide wheels; the making the
exterior cylinder of two unequal diameters to form a steamway in one part
and steam stops in the other; and the general arrangement and constructive
combination of the parts by which the pistons or valves and interior cylinder
can be made to rotate in either direction; the whole constructively, collectively,
and substantially, with the effects and in the manner described and shewn.
In witness whereof, I, the said Stephen R. Parkhurst, have hereunto
set my hand seal, this Fifteenth day of May, in the year of our Lord
One thousand eight hundred and forty-seven.
STEPHEN R. (L.s.) PARKHURST.
Taken and acknowledged by Stephen
R. Parkhurst (party hereto), at
the City of New York, this Fif-
teenth day of May, 1847, before
Her Britannick Majesty's Consul.
A.
This is the Specification referred to in the Affidavit of Samuel Carpmael,
sworn before me, this 14th day of July, 1847.
J. W. FARRER.
Samuel Carpmael, of Lincoln's Inn, in the County of Middlesex, Gentleman,
maketh oath and saith, that he is acquainted with the manner and character
of the handwriting of Anthony Barclay, Her Britannic Majesty's Consul at
the City of New York, in the United States of America. And this Deponent
further saith, that the signature "Anth. Barclay," set, subscribed; or written
in the margin of the Specification hereunto annexed, marked A, and dated the
Fifteenth day of May now last past, and purporting to be executed by Stephen
R. Parkhurst, of Leeds, in the County of York, within the Kingdom of

page_text: England, whereby it is stated that the Specification aforesaid was acknowledged
by him, the said Stephen R. Parkhurst, before the said Anthony Barclay, on
the said Fifteenth day of May, at the City of New York aforesaid, is of the
proper handwriting of the said Anthony Barclay.