IMPROVEMENTS IN ROTARY STEAM ENGINES
Year: 1868

page_text: LETTERS PATENT to William Brookes, of 62; Chancery Lane, in the
County of Middlesex, Civil Engineer and Patent Agent, for the.
Invention of "IMPROVEMENTS IN ROTARY STEAM ENGINES."-A com-
munication from abroad by Leon Hamar, of Pest, in the Kingdom of
Hungary.
Scaled the 22nd December 1868, and dated the 1st July 1868.

page_text: steam. Two opposite floats are connected together by the framework
v, y, and x, z, which respectively cross one the other in the centre of the
axis O; the frames of these floats are constructed in such a way that the
narrow frame may freely pass within and clear of the larger one; to the
ends of these frames are fitted the floats v, x, y, z, which are furnished
inside with springs having the double purpose of fitting to the engine in
all its parts and of compensating for wear. These frames also fit into
holes or rather mortices contrived in the wheel or hollow cylinder e, f, g, h,
which are composed of four picces fastened to the journal with screws as
shown. The inner line or contour of the engine shown in section,
Figure 1, is constructed in the following way:--The part a, b, forms a
quadrant of an arc of a circle drawn with the radius 0, 6; opposite to
this one is to be seen the quadrant of a larger are of circle having its
centre equally in O, the radius of which, however, is by so much longer
than the radius O, b, as the steam bearing part of the floats amounts to
in radial length. In the adjoining Drawing the length of the bearing
part of the floats w, y, is exactly the part of the radius o, y. These two
quadrants of two different arcs of circles being thus struck opposite each
other are connected together with the curves b, c, d, and a, x, c; these
curves, however, are to have the following construction -Suppose a
ruler equal in length to the sum of the two radii before-mentioned be.
not only turned round, but simultaneously slid along the common centre
O and slid with a ratio corresponding to the difference of the two radii,
the two extremities of the ruler will then describe these curves; thus
the afore-mentioned two frames holding the floats v, y, and z, x, and
sliding to and fro in a diametrical direction in the journal will in all
their several positions exactly clear and fit the interior of the belt. The
length of the steam-bearing part of the floats is optional. In the case
illustrated by the annexed Drawings this length is part of the radius,
but it might as well be its or part, but then the delineation of the
interior of the belt would alter accordingly.
In the polycircular space
so constructed the floats make the following alternate movement, namely,
while steam is pushing the float y in the direction of the arrow the radial
length of the bearing part of float y in the fourth arc of a circle c, d,
remains unaltered and the float on the other end of the same frame will
move in the smaller quadrant a, b, and will also maintain its own radial
length, but the floats fitted to the second frame, clearing the while the
connecting curves, will change their radial length; thus, whilst the float x
turning towards b, is being pushed back by the eccentric bend b, x,

page_text: the float being on the same frame will be provided in the same
ratio until it reaches the larger quadrant. The unceasing and
alternate movement of the floats is thus described. But in order
to make steam on its entering the engine bear efficaciously, and as
soon as possible on the motor, the orifice of the admission pipe A is
trumpet-shaped, so that the diametrical width of the admission pipe
reaches at last the dimension a, c. In the rectangular grooves
contrived right and left of each mortice small iron plates are introduced
in a diagonal direction, their outward edge being pressed on by spiral
springs they have the object of keeping out steam from the interior of
the wheel and are no other than an application of the well-known Bramab
obturation. One end of the wheel constantly adheres while turning to
the very wall of the case of the engine whilst the other end is fitted by
the adjusting disc a, b, x, d, c, y, held by adjusting screws to compensate
for wear arising with time. The steam admission pipes A or B are
connected with a particular cock, by means of which steam may be con-
veyed either through the aperture A or B according as the engine is
desired to turn to the right or the left. By means of this same cock
steam may also be suddenly shut out.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Brookes in the Great Seal Patent Office
on the 31st December 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
BROOKES, of 62, Chancery Lane, in the County of Middlesex, Civil
Engineer and Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of July, in the year of
our Lord One thousand eight hundred and sixty-eight, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Brookes, Her special licence
that I, the said William Brookes, my executors, administrators, and
assigns, or such others as I, the said William Brookes, 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

page_text: vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
ROTARY STEAM ENGINES," a communication to me from abroad by Leon
Hamar, of Pest, in the Kingdom of Hungary, upon the condition (amongst
others) that I, the said William Brookes, my executors or administra-
tors, 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 per-
formed, 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 I, the said William Brookes, do hereby declare
the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and
by the following statement thereof, that is to say :-
The object of these improvements in rotary steam engines is simplicity
of construction and efficiency of action.
But that the Invention may be fully understood I will by the aid of
the accompanying Drawing proceed to describe the same.
DESCRIPTION OF THE DRAWING.
Figures 1 and 2 are two external views of the engine; Figures 3 and
4 are sections thereof; Figures 5 and 6 shew parts separately.
O indicates the excentrical axle of the inner rotary contrivance; c, d,
are the oil pipes for lubricating the inner mechanism; e is a cock by
means of which the steam condensed may be drawn or blown off. A
and B are steam passages formed opposite to each other. The adjusting
screws marked 1, 2, 3, 4, 5, are for holding a disk a, b, and c, d, y, to
the inner rotary mechanism, by means of which wear may be com-
pensated. A is an aperture or passage of one of the steam introducing
pipes. These steam introducing pipes or passages which open into the
engine trumpet-shaped, and of which there is one on each side of the
engine alternately either let in or let off steam, that is to say, when
the engine is working both these pipes are constantly operating, but one
performing always the opposite service of the other; they alternate this
service according as the engine is to be turned one way or the other.
The sections shew the four floats or paddles which are successively

page_text: operated on by steam. Two opposite floats are connected together by
the frames i and j, which respectively cross one over the other in the
centre of the axis O. The frames of these floats are constructed in such
a way that the narrow frame i may freely pass within and clear of the
larger one j. To the ends of these frames are fitted the floats v, x, y, z,
which are furnished inside with springs having the double purpose of
fitting to the interior of the engine and of compensating for wear therein.
These frames also fit into holes or rather mortices contrived in the
hollow internal cylinder e, f, g, h, which is composed of four pieces
fastened to the axis O with screws as shown. The inner line or contour
of the case of the engine (shown in section Figure 3) is constructed in
the following way:-The part a, b, forms a quadrant of an arc of circle
drawn with the radius O, b. Opposite to this one is to be seen the
quadrant of a larger arc of circle having its centre also in O, the radius
of which however is by so much longer than the radius O, b, as the
steam bearing part of the floats amounts to in radial length.
In the accompanying Drawing the length of the bearing part w, y, of
the floats is exactly the part of the radius O, y. These two quadrants
of two different arcs of circles being thus struck opposite each other
are connected together by the curves b, c, d, and a, z, c. These curves
however are to have the following construction:-Suppose a ruler equal
in length to the sum of the two ralii before mentioned be not only
turned round but simultaneously slid along the common centre O and
slid with a ratio corresponding to the difference of the two radii, the
two extremities of the ruler will then describe these curves. Thus the.
afore-mentioned floats o, y, and z, x, carried by the frames i and j sliding
to and fro in a diametrical direction in the journal or axle O will in their
several positions exactly clear and fit the interior of the case. The length
of the steam bearing part of the floats is optional. In the case illustrated
by the annexed Drawing this length is part of the radius, but it might
as well be its or part, but then the delineation of the interior of the
case would alter accordingly. In the polycircular space so constructed
the floats make the following alternate movement, namely, while steam
is pushing the float y in the direction of the arrow the radial length of
the bearing part of float y in the fourth arc of a circle c, d, remains
unaltered, and the float on the other end of the same frame will move
in the smaller quadrant a, b, and will also maintain its own radial length,
but the floats fitted to the second frame clearing the while the con-
necting curves will change their radial length, thus whilst the float a

page_text: turning towards 6 is being pushed back by the eccentric bend b, x, the
float being on the same frame will be protended in the same ratio
until it reaches the larger quadrant. The unceasing and alternate move-
ment of the floats is thus described. But in order to make steam on its
entering the engine bear efficaciously and as soon as possible on the motor
the orifice of the admission pipe A is trumpet-shaped, so that the diametrical
width of the admission pipe reaches at last the dimensions a, c. In the
rectangular grooves contrived right and left of each mortice small
plates 1, 1, are introduced in a diagonal direction, their outward edge
being pressed against the floats by spiral springs which have the
object of keeping out steam from the interior of the wheel, and are an
application of the well-known Bramah obturation or packing. One
end of the wheel constantly is in contact while turning with the case
of the engine, whilst the other end is fitted by the adjusting disc
a, b, x, d, c, y, and held by adjusting screws 1, 2, 3, 4, 5, to compensate
The steam admission pipes A or B are connected by a suitablé
cock or valve, by means of which steam may be conveyed either through
the aperture A or B according as the engine is desired to turn to the
right or the left. By means of this same cock or valve steam may also
be suddenly shut out.
Having thus described the Invention and means which I adopt in
carrying the same into effect, I would have it understood that what I
claim as the Invention communicated to me is, the adaptation or
combination of parts for forming rotary steam engines, substantially as
described.
In witness whereof, I, the said William Brookes, have herc-
unto set my hand and seal, this Thirty-first day of December,
in the year of our Lord One thousand eight hundred and sixty-
eight.
WILLIAM BROOKES. (L.S.)