IMPROVEMENTS IN ROTARY ENGINES
Year: 1884

page_text: I, GEORGE THOMPSON LEITCH, of 235 Hospital Street, Glasgow, in the County'
of Lanark, North Britain, Engineer do hereby declare the nature of the said
invention for "IMPROVEMENTS IN ROTARY ENGINES" to be as follows:-
. This Invention, which relates to Rotary Engines, consists of a cylindrical mass
of metal rotating either within a cylinder, or within an enclosing casing or body, a
part of whose inner periphery is of a regular curved form, the remaining part being
composed of irregular curves. The rotating mass of metal, whose axis is arranged
eccentrically with that of the enclosing casing, has a slot formed diametrically
through it, into which is fitted a sliding piece. The sliding piece is provided at its
edges with packing pieces of an approximately semicircular section which always,
move to a position corresponding to the relative positions at any moment of the
sliding piece and the internal part of the cylinder or casing.-These packing pieces
are forced outwards at their inner sides by springs, which are fitted in the said sliding
piece, so that in rotating, the outer edges of these packing pieces are caused to bear
with the necessary pressure against the inner surface of tho enclosing casing, and
thereby prevent the escape of steam.—There is a similar packing piece fitted into
both ends of the sliding piece, so that the said sliding piece, at its ends, is main-
tained steam-tight.-For the purpose of preventing the escape of steam at or around
the ends of the cylindrical mass of metal, the covers of the casing are each provided
with a packing ring which being forced endwise against the cylindrical mass also
outwards by the expanding action of a spiral spring keeps the parts in tight
working order.-The admission and exhaust ports to and from the enclosing casing
are arranged at a distance apart sufficient to allow of the expansion of steam in
passing through the engine, that is to say, the steam admitted to one side
and edge of the sliding piece at the one port, is cut off by the opposite edge of the
sliding piece when it passes the said port; the steam already within the engine,
being allowed to expand until the first referred to side and edge of the sliding
piece is opposite the exhaust port. The ports are provided with a slide valve or
cock for regulating the admission of steam.-When the engine is made to reverse it
is provided with a double set of admission and exhaust ports through which the
steam is admitted and exhausted by one and the same valve or cock. Springs are
fitted upon the ends of the enclosing casing, bearing.upon the shaft in such a direction
as to cause the outer periphery of the rotating mass of metal carrying the slide, to
press always against the inner surface of the enclosing casing between the admission
and exhaust ports to prevent the steam from passing at such part.
Thin fiftaruth day of October 1884
J. H. JOHNSON, DAY & JOHNSON,
.Petitioner's Agents,
115, St. Vincent Street, Glasgow,

page_text: I, GEORGE THOMPSON LEITCH of 235 Hospital Street, Glasgow, in the County
of Lanark, North Britain, Engineer do hereby declare the nature of my invention
for IMPROVEMENTS IN ROTARY ENGINES and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
This Invention, which relates to Rotary Engines, consists of a cylindrical mass of
metal rotating either within a cylinder or within an enclosing casing or body; a
part of whose inner periphery is of a regular curved form, the remaining part being.
composed of irregular curves.-The rotating mass of metal, whose axis is arranged
eccentrically with that of the enclosing casing, has a slot formed diametrically
through it, into which is fitted a sliding piece. The sliding piece is provided at its
edges with packing pieces of an approximately semicircular section which always
move to a position corresponding to the relative positions at any moment of the
sliding piece and the internal part of the cylinder or casing.--These packing pieces.
are forced outwards at their inner sides by springs, which are fitted in the said
sliding piece, so that in rotating, the outer edges of these packing pieces are caused
to bear with the necessary pressure against the inner surface of the enclosing
casing, and thereby prevent the escape of steam.-There is a similar packing piece
fitted into both ends of the sliding piece, so that the said sliding piece, at its ends,
is maintained steam-tight.-For the purpose of preventing the escape of steam at or
around the ends of the cylindrical mass of metal, the covers of the casing are, each
provided with a packing ring which being forced end wise against the cylindrical
mass also outwards by the expanding action of a spiral spring keeps the parts.in
tight working order.-The admission and exhaust ports to and from the enclosing
casing are arranged at a distance apart sufficient to allow of the expansion of steam
in-passing through the engine, that is to say, the steam admitted to one side and
edge of the sliding piece at the one port, is cut off by the opposite edge of the
sliding piece when it passes the said port, the steam already. within the engine
being allowed to expand until the first referred to side and edge of the sliding piece
is opposite the exhaust port.-The ports are provided with a slide valve or cock for
regulating the admission of steam.-When the engine is made to reverse, it is pro-
vided with a double set of admission and exhaust ports through which the steam is
admitted and exhausted by one and the same valve or cock.-Springs are fitted
upon the ends of the enclosing casing bearing upon the shaft in such a direction as
to cause the outer periphery of the rotating mass of metal carrying the slide, to
press always against the inner surface of the enclosing casing between the admission
and exhaust.ports to prevent the steam from passing at such part.
In order that my said Invention may be most fully understood and readily carried
into effect, I will proceed to describe the Drawings hereunto annexed.
Figures 1, and 2, are respectively an end elevation and a side elevation of a rotary
engine constructed according to and constituting my present Invention.
Figure 3, is an elevation of the same at the end opposite to that of Figure 1.
Figure 4, is a transverse section through the same and through the exhaust ports
thereof.
'
Figure 5, is a longitudinal section through the same.
Figure 6,. is a transverse section through the same, and through the admission
ports thereof. =
The other figures of drawing are hereinafter more particularly referred to and
described in the body of the Specification

page_text: In carrying out my present Improvements, I arrange the cylindrical mass a, of
metal, to rotate either within a cylinder or within an enclosing casing or body such
as is represented at b, upon the annexed drawings, a part of whose inner periphery
is of a regular curved form, the remaining part being composed of irregular curves.
-The rotating mass a, of metal, whose axis is arranged eccentrically with that of
the enclosing casing b, has the slot c, formed diametrically through it and into this
slot, the sliding piece d, is fitted. The rotating mass a, of metal is preferably
formed in part with the shaft c, which has its bearings in the covers f, of the
enclosing casing b, one end of the said shaft e, passing outwards through the
gland g, and stuffing box h, and provided with the band or equivalent wheel i,
secured thereon. The sliding piece d, is provided at its edges with the packing
pieces j, of an approximately semi-circular section, which always tend to adjust
themselves to a position corresponding to the relative positions, at any moment, of
the sliding piece d, and the internal part of the cylinder or casing b, in contact
therewith. Figures 7, 8, and 9, represent the sliding piece d, respectively in side
elevation, plan and in end elevation.-With reference to these Figures it will be
seen that the hereinbefore mentioned packing pieces j, have their bearings within
the hollow edges of the said sliding piece d, and are thereby enabled readily to
adjust themselves to any required position. The packing pieces j, I prefer to form.
of an elastic or springy construction. Figures 13, and 14, are respectively a plan
and a side elevation of such a construction of packing, the transverse section of
which is represented at Figures 4, and G.-These packing pieces j, are formed of two
or more portions as represented in plan at Figure 15, wherein these portions are
shewn as drawn apart. It will be seen with reference to these Figures of Drawing
that the joint between the two portions of the packing pieces j, is made transversely
steam-tight by means of the "lap" k, at the joint thereof, while at the upper and
lower surfaces of the said packing pieces the tongues 1, formed on one portion fit
into corresponding recesses formed in the adjacent portion thereof. These two or
more portions have secured at their interior the diaphragms m, or their equivalent,
so that a spring located and compressed between those diaphragms tends to press
the two portions of the packing asunder or when within the enclosing casing b,
press the ends of the said packing pieces against the inner surfaces of the covers f,.
and thereby render them practically steam-tight at that part, so borne upon. The
packing pieces j, of the section shewn upon the annexed drawings is such as
will allow the steam, or other medium employed for driving the engine, to onter
the same and thereby tend to spring or force the outer bearing surface thereof
against the inner periphery of the enclosing casing b, so that the tendency is to
maintain the said parts steam-tight. At one or both ends of the sliding piece d,
there is or are arranged a packing piece or pieces to maintain this or these parts
practically steam-tight. In place however of providing such means at the
two ends of the said sliding piece d; I prefer to provide means at one end
thereof, arranged with a spring, which, in itself, is sufficient to force the
packing piece so employed and the sliding piece d, in opposite directions against
the two covers f, and thereby render the same practically steam tight at these
parts. This arrangement is illustrated at Figures 7, to 12, (inclusive) Figures 10,
11, and 12 representing the said packing piece, respectively. in side and front
.elevations and in plan.-The portion m¹, of the packing piece m, fits into the
recess o, formed in the sliding piece d, in which it is free to move longitudinally.
A spiral or equivalent spring is located within the recess p, and tends to force the
packing piece n, outwards from the said sliding piece, so that when in position
within the enclosing casing, these portions are forced against the inner faces of the.
covers f-For the purpose of preventing the escape of steam at or around the
ends of the cylindrical mass a, of metal, the covers f, inay each be provided
with a packing ring, but, I prefer to arrange a packing ring upon one end of the
said rotating mass a.-This packing ring which is represented at p³, at Figure 5,
of the annexed drawings, is capable of sliding longitudinally upon the rotating

page_text: mass a, upon which it is mounted, but is secured against any rotary movement
thereon by means of the clutch device q. Between the adjacent surfaces of the:
packing ring p, and the rotating mass a, springs are arranged in such manner as
to cause the two parts to be pressed outwardly in opposite directions so that the
extremities of the said parts are pressed practically steam-tight against the covers.f,
of the enclosing casing b.-By the series of projections and recesses, constituting
the clutch device q, it is seen that the joint between the two parts is maintained
transversely steam tight. The admission ports r, and the exhaust 'ports 8, to and
from the enclosing casing b, as shewn respectively at Figures 6, and 4, of the
annexed drawings, are arranged at a distance.apart, circumferentially, sufficient to
allow of the expansion of steam in passing through the engine, that is to say, the
steam admitted to one side and edge of the sliding piece d, at one port r, is cut off
by the opposite edge of the sliding piece d, when it passes the said port r, the
steam already within the enclosing casing b, being allowed to expand until the
first referred to side and edge of the sliding picce d, is opposite the exhaust port s.—
The Engine represented upon the annexed drawings is arranged for working in
either direction and it is provided with 'a, steam cock for reversing and mani-
pulating the said engine. The steam cock represented consists of the plug t, which
is so formed that when turned into one position it admits steam through the
openings', 'and v, respectively and through the port w, to one of the admission
ports, thereby admitting steam to one side of the sliding piece d, and exhausting
it from the opposite side through one of the exhaust ports and port x, through
the opening into, and out from the end of the plug t, and exhaust pipe.connected
therewith. When' the plug t, is turned in the opposite direction steam is admitted
through the openings v, and u, respectively, and through the port y, to the other
admission port r, thereby admitting steam to the opposite side of the sliding
piece d, and thus reversing the motion of the engine. The steam under such
reversal exhausts from the engine by the ports s, and, and out through the plug t,
as herein before described.-Adjacent to the shaft e; there are provided means
whereby an approximately constant pressure, may be maintained and adjusted
between the portion of the periphery of the rotating mass a, which is in contact
with the inner periphery of the enclosing casing b, so as to prevent the incoming
steam' passing at this part to the exhaust port 8, at the opposite side thereof. Upon
the annexed drawings I have shewn a means whereby this adjustment may be
effected. The set-screws a¹, are arranged to screw into or out from the sockets b¹,
which are preferably formed in part with the cover f, casting.-These sockets 61,,
'are screwed at their interior preferably with fine threaded screws, so as to be
capable of fine adjustment.-Upon the ends of 'the screws a¹, the spiral springs c¹,
or equivalent springs are or may be caused to be compressed between the said ends
of the screws a', and the plugs or bearing 'pieces d', 'which are thereby caused to
'bear in the required direction upon the shaft e.
The configuration or contour of the inner periphery of the enclosing casing b,
and position thereof relatively with that of the rotating mass a, of metal with its
complement of sliding piece d, and packing pieces j, located within it, is such that
during a rotation of the said mass a, the portions of the periphery of the enclosing
casing b, borne upon by the packing pieces j, are equidistant throughout the said
configuration or contour being such as to admit of the expansion of the stem in
passing through the engine.
9
T
For starting, stopping and reversing 'the engine, I prefer to employ the hand
'lever e, secured to the plug t, and arranged to operate in proximity to the
indicating quadrant g', to' which it may be secured in any desired position by means
of the fly-nut f¹, or its equivalent.
It is to be understood although I have represented upon the annexed drawings
an Engine for operating in either direction, that I may construct a single acting
engine, in which case, one set of admission and exhaust ports is dispensed with. It
is further to be unders'ood although I have shewn the engine upon the annexed
0

page_text: drawings to te reversed and manipulated by means of the steam cock hereinbefore
described, that I may effect the same by means of a slide or other equivalent form
of valve.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
>
-
First. The improved rotary Engine either as a reversing or non-reversing engine
substantially as herein before described and shewn upon the annexed drawings."
Second. The end packing ring p', substantially as and for the purposes herein-
before set forth with reference to the annexed drawings.
Third. The packing pieces j, substantially as and for the purposes herein before
set forth with reference to the annexed drawings.
Fourth. The constructing of a portion of the enclosing casing b, of an irregular
curved form substantially as and for the purposes hereinbefore set forth with
reference to the annexed drawings.
Dated this Twelfth day of January 1885.
•
J. H. JOHNSON, DAY & JOHNSON,.
Applicant's Agents.