IMPROVEMENTS IN ROTATORY MOTOR ENGINES
Year: 1884

page_text: I WILLIAM MACILWRAITH of Anglesea Street in the City of Cork Engineer,
do hereby declare the nature of my Invention for IMPROVEMENTS IN ROTATORY
MOTOR ENGINES, to be as follows:-
My improvements in Rotatory Motor Engines consist in arranging a piston,
having a central cylindrical body, on a shaft, which passes through the centre of
a cylinder provided with covers and stuffing boxes in the usual manner.
The central body of the piston is of smaller diameter than the cylinder and has
formed upon it one or more projections or wings which touch the inner periphery
of the cylinder with their outer edge and the cylinder covers with their ends, and
are provided with packing strips and rings in the usual manner.
To form an abutment for the steam or other pressure to act against and drive
the piston round I form a second cylinder parallel with the power cylinder, and
having its axis coinciding or nearly so with the inner periphery of the power
cylinder. The abutment cylinder is fitted with a solid block revolving on an axis
which passes through bearings in the end covers, and is of such a diameter that
the periphery of the block touches the cylindrical body of the power piston.
A curved recess is made in the abutment block in which the projecting wing or
wings of the power piston can slide and pass; the axis of the abutment block is
geared with toothed gearing to the shaft of the power cylinder in the same
proportion that there are projections or wings on the power piston, so that if there
is one projection or wing on the power piston both it and the abutment block will
make equal revolutions, if there are two projections the abutment block will mako
two revolutions to one of the power piston, if three projections thrco revolutions
and so on.
The object being that the recess in the abutment block shall always be
presented to the passing projection or wing of the power piston at the proper
moment.
Immediately above the abutment cylinder is placed the admission valve having
its port opening directly into the power cylinder, the valve itself being by
preference of the "corliss" type actuated by a lever on its axis and a connecting
link from a crank pin or an eccentric on the axis of the abutment block.
The exhaust passage is situated immediately below the abutment cylinder and
opens direct into the power cylinder, the exhaust passage is never altogether
closed as the outer edge of the projection or wing of the power piston is made
narrower than the width of the exhaust passage.
Dated thin Oth do 100

page_text: CORT DELE
I WILLIAM MACILWRAITH of Anglesea Street in the City of Cork, Engineer,
do hereby declare the nature of my Invention for IMPROVEMENTS IN ROTATORY
MOTOR ENGINES and in what manner the same is to be performed, to be parti-
cularly described and ascertained in and by the following statement, and in order
that the same may be more clearly understood I have hereunto appended two
sheets of drawings:-
In sheet No 1 Fig 1. is a cross section: and Fig: 2 an end elevation of one
arrangement of my invention.
A piston A having a central cylindrical body is mounted on the shaft S which
passes through the axis of the cylinder B-Covers and stuffing boxes of the usual
construction are provided for the cylinder.-The central body of the piston A has
two wings or projections a formed upon it, which touch the inner periphery of the
cylinder B with their outer edges and the cylinder covers with their ends, and are
provided with packing strips and rings of the usual construction.
To form an abutment for the steam or other fluid pressure to act against and
drive the piston A round in the cylinder B, I form a second cylinder C parallel
with the power cylinder B and having its axis coinciding or nearly so with the
inner periphery of the power cylinder B. The abutment cylinder O is fitted with
a solid block D which revolves in it and is provided with an axis passing through
bearings in the end covers. The abutment block D is of such a diameter that its
outer periphery touches that of the cylindrical body of the piston A; a curved
recess d is made in the abutment block D in which the wings or projections a of
the piston A can slide and pass. To present the recess d to the wings or pro-
jections a in proper time for them to pass as they revolve, I gear the shaft of the
piston A to the axis of the abutinent block D with toothed gearing T and T¹ in the
proportion of two to one so that the block D makes two revolutions to one of
the piston A. To admit the steam between the projecting wing a of the piston A
and the abutment block DI place a steam valve E, by preference of the "Corliss "
type and which oscillates in a circular steam chamber e immediately above the
abutment cylinder C. A steam port F admits the steam from the valve to the
space between the piston wing a and the abutment block D. Motion is given to
the valve E by a crank pin G on the axis of the abutment block D acting through
the connecting rod H and the lever I on the axis of the steam valve E. The
exhaust port K is placed immediately below the abutment block D and is always
open.
In sheet 2 Figures 3 and 4 represent in cross section and in end elevation
respectively a modification of my invention. In this, the piston A has two wings
or projections a as before described and the cylinder B is provided with two
abutment cylinders C and C, two steam admission valves E and E, and two
exhaust ports K and K¹ set diametrically opposite to one another. The abutment
blocks D and D₁ are geared with the toothed wheels T¹ and T to the wheel T
on the piston shaft S so as to make the same number of revolutions with it and
each block is made with two curved recesses & and in which the wings or
projections a of the piston A can slide and pass,

page_text: The steam is admitted on each side of the piston wings a by the steam valves E
and E which are operated as before described by the crank pins G and G' through
the connecting rods H and H' and the levers I and I.
I do not confine myself to the exact number of wings or projections a on the
piston A, or to the number of abutment blocks D shewn on the drawings, as each
may be varied according to the size of the Engine required. The abutment blocks
being geared to the piston in proportion to the number of recesses in the one and
the number of wings or projections on the other so that the latter may slide and
pass in the former,
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
The construction of the cylinder B having a central revolving piston A with one
or more wings or projections o in combination with one or more abutment
cylinders C and recessed revolving abutment blocks D, substantially as shewn and
for the purposes described or any mere modification thereof.