AN IMPROVED ROTARY ENGINE
Year: 1884

page_text: [Communicated from abroad by John J. Blair, of Tacoma, Pierce County,
Washington Territory, and Alfred W. Black, of Portland, Multnomah
County, and State of Oregon, both in the United States of America.]
PROVISIONAL SPECIFICATION.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of the said Invention for "AN IMPROVED
ROTARY ENGINE," a communication to me from abroad by John J. Blair, of Tacoma,
Pierce County, Washington Territory, and Alfred W. Black of Portland, Multnomah
County, and State of Oregon, both in the United States of America, to be as
follows:-
'
This invention relates to a rotary engine in which the cylinder revolves upon a
stationary piston.
The cylinder is cylindrical externally and of elongated form in cross section
internally so as to form meniscus shaped steam spaces between it and the
cylindrical piston and at opposite sides of the latter. The cylinder heads have
journals mounted in bearings and concentric with the axis of the piston which is
cylindrical and has a shaft passing through one of the cylinder journals. The
cylinder has two longitudinal packing strips at opposite points on its shortest
diameter which embrace the periphery of the piston and with the cylinder revolve
about it. The piston is cylindrical and hollow and has a central cylindrical valve
chamber from which two pairs of radial ports lead out to the periphery of the
cylinder where they open out beneath two pairs of swinging gates or abutments.
These abutments extend the whole length of the piston and swing outwards across
the steam space being moved out by the steam pressure until they coincide with
the periphery of the cylinder. The two pairs swing in opposite directions and are
used one pair at a time according to the direction in which the engine is running.
Within the valve chamber is fitted a valve carrier which is caused to rotate within
the stationary piston with the cylinder by an axial connection with the opposite
cylinder head to that through which the piston shaft passes. The carrier carries
two opposite valves which are thus caused to revolve with the cylinder and
alternately open and close the radial ports in the piston. The two pairs of ports
31

page_text: are in different transverse planes and between the said valves, are fitted a pair of
reversing valves capable of being adjusted longitudinally between the first
mentioned valves so that steam shall be admitted through one or other pair of
ports as required. These reversing valves are connected with collars on the end of
a sliding rod passing axially through the piston shaft. Steam is admitted to the
valve chamber from the interior of the piston to which it is conveyed through a
longitudinal passage in the piston shaft connected by a hollow collar thereon with
the steam pipe. The piston has a diametral exhaust passage at one end communi-
cating by another longitudinal passage in the piston shaft and another hollow
collar, with the exhaust pipe. A packing plate is fitted in one head of the
cylinder and pressed against the end of the piston by steam admitted behind it.
Dated this 26th day of March 1884

page_text: Reference is. to be had to the accompanying drawings forming part of this
Specification in which similar letters of reference indicate corresponding parts in
all the figures.
Figure 1 is a longitudinal sectional elevation of my improved revolving cylinder
engine.
Figure 2 is a cross sectional elevation of the same on the line x x figure 1.
Figure 3 is a cross sectional elevation of the same on the line y y figure 1.
Figure 4 is a cross sectional elevation of the same on the line x x¹ figure 1.
Figure 5 is a cross sectional elevation of the same on the line y y¹ figure 1. ·
Figure 6 is a face view of the packing plate of the cylinder.
Figure 7 is a perspective view of the reversing.valve.
Figure 8 is a cross sectional elevation showing the valves.
The cylinder A is made cylindrical externally and of elongated form in cross
section internally and is fitted with longitudinal packing strips C at opposite
points on its shortest diameter. A¹.and A2 are the cylinder heads, of which the
former is provided with a tubular journal D' and the latter with a journal D³ both
of which are concentric with the axis of the piston and are mounted in proper
bearings. The cylinder A contains and rotates about the hollow cylindrical
piston E, from one end of which the shaft F projects through the tubular journal D¹.
It is provided with a longitudinal partition F1 dividing it into the steam inlet
passage G, and the exhaust passage G. H, and H¹ are hollow collars encircling
shaft F and in communication respectively with the passages G G¹ and coupled by
necks h h. with the steam inlet and exhaust pipes. One of the collars is shown in
section in figure 4. The piston E is embraced at opposite sides by the packing
strips C and is provided with a transverse exhaust port E¹ which leads to the
exhaust passage G. The piston is provided with four swinging gates or
abutments J extending the whole length of the piston which swing outward from
the piston and come against the inner walls of the cylinder space B, the gates or
abutments being moved outward by the steam pressure behind them and inward
by contact with the walls of cylinder space B. These abutments are used in pairs,
one pair for running in each direction. A pair of steam ports K or K¹ conducts
the steam from the middle of the piston to the steam space, between the piston and
cylinder, said ports opening out beneath the flanges or lips m formed on the outer
or swinging edges of the gates or abutments J, so that when the steam is admitted
through the ports, the pressure of the steam first swings the gates or abutments J
outward. In the middle of the piston a cylindrical valve chainber L is formed, in
the end of which a cylindrical journal block M is screwed, which is mounted'
loosely on a valve stem M having one end screwed into the cylinder head A' and
the other end M2 squared and received in an aperture in the end of a cylindrical'

page_text: valve carrier N fitted in the valve chamber L. This valve carrier carries the two
opposite valves 0. As the valve stem M' revolves with the cylinder head A², the
valve carrier N into which the squared end M' of the valve stem projects, will also
be revolved within the valve chamber L. The two pairs of ports K K' are in
different transverse planes and between the valves O similar valves P are fitted
which act as reversing valves and are about half the length of the valves O. These
valves P so far as they extend fill up the space between valves O and have each a
stud P1 (figure 7) at back, which studs project into an annular groover formed on
the inner end of the rod R which passes axially through the shaft F and through
the valve carrier N and is capable of being slid lengthwise for shifting valves P so
as to open ports K and close ports K¹ or vice versa, according to the direction in
which the engine is to be driven. In the inner surface of the head A¹ a packing
plate S is fitted which is acted upon by steam admitted to the space behind the
said packing plate through apertures & figure 6, whereby the said packing plate is
pressed against the ends of the gates or abutments and thus form a tight joint.
The operation is as follows:-The piston remains stationary and the cylinder
revolves as shown by the arrow in figures 2 and 3. The steam acts on the sides of
the cylinder in both halves of the same, so that each gate J of the pair in use is
opened twice for each revolution. The steam enters through the collar H, the
passage G, into the hollow piston and then passes through the channels K or K³,
throws outwards the gates or abutments opposite these channels, reacts against the
abutments and thus revolves the cylinder. Although the piston is stationary its
. valves O revolve with the valve carrier and thus alternately open and close the
channels K-or-K-that is, the channels-are-open-as-long-as-steam-is-to-be-admitted-
and are closed as soon as or before the gates or abutments are pressed back against
the piston. The steam is admitted into the meniscus shaped sten in spaces between
the inner surface of the cylinder and the outer surface of the piston only during
one quarter of a revolution and for the other quarter of the revolution, the steam
works expansively. As shown in figures 2 and 3 the pairs of gates or abutinents
swing in opposite directions so that if the cylinder will revolve in one or other
direction according as one or other pair is thrown outwards by the steam passing
through the one or other pair of ports K K¹.
The engine can thus be reversed very easily and. readily by simply shifting the
valves P which control said ports by means of the rod R.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is :-
1. In a revolving cylinder rotary engine the combination with a fixed hollow
cylindrical piston, of the swinging gates or abutments J the revolving cylinder A
and the revolving valves O held within the cylindrical valve chamber in the piston,
substantially as herein shown and described.
2. In a revolving cylinder rotary engine the combination with a fixed hollow
cylindrical piston of the swinging gates or abutments J, the revolving cylinder A,
the revolving valves O held within the cylindrical chamber in the piston and of
the sliding valves P, adapted to close the ports K, or K', substantially as herein
shown and described.
3. In a revolving cylinder rotary engine, the combination with a fixed hollow
cylindrical piston; of the swinging gates or abutments J, the revolving valves O
held within the cylindrical chamber in the piston, the sliding valves P adapted to
close either the ports K or K', substantially as herein shown and described.
4. In a revolving cylinder rotary engine the combination with a fixed cylindrical
hollow piston E of the revolving cylinder A, the revolving valves held in a
cylindrical chamber L in the piston, the sliding valves P, having projections P1, the
sliding rod R in the shaft of the piston and provided with an annular groove
engaging with the projections P" of the valves P, substantially as herein shown
and described.

page_text: 5. In a revolving cylinder rotary engine, the combination with a fixed hollow
cylindrical piston E, of the revolving cylinder A, the revolving valves O held in n
cylindrical chamber L in the piston, the valve carrier N, the cylindrical journal M,
and the valve stem M' secured in one head of the cylinder and connected with the
valve carrier N, in such a manner as to turn the same, substantially as herein
shown and described.
6. In a revolving cylinder rotary engine, the combination with the fixed piston E
having a cylindrical chamber L in the middle, the cylinder A, the valve carrier N,
the valves O, the valve stem M' secured in the head A of the cylinder, the
cylindrical journal block M, mounted on a valve stem M¹ having a squared end M²
projecting into a recess in the valve carrier, substantially as herein shown and
described.
7. In a revolving cylinder rotary engine, the combination with the fixed piston E
provided with two pairs of gates or abutments J for running in opposite directions,
of the revolving cylinder A, the shaft F, connected with the piston and provided
with a steam inlet passage G and steam outlet passage G¹, substantially as herein
shown and described.
"
8. In a revolving cylinder rotary engine, the combination with the fixed piston E,
provided with two pairs of gates or abutments J for running in opposite directions,
of the revolving cylinder A, the shaft F, connected with the piston and provided
with the steam inlet passage G and the steam outlet passage G¹ and of the
collars H H held on the shaft and connected with the steam inlet and exhaust
pipes, substantially as herein shown and described.
9. The combination with a cylindrical piston, of a cylinder the internal form of
which is two semi-cylinders elongated at the base or diameter edges beyond the
middle of the circle, whereby two meniscus shaped steam chambers will be formed
between each half of the piston and the corresponding half of the cylinder,
substantially as herein shown and described.
10. The combination with the cylindrical piston, of a cylinder, the internal form
of which is two semi-cylinders united at their base or diameter edges and elongated
at the said edges beyond the middle of the circle, whereby two meniscus shaped
steam chambers will be formed between the surface of the piston and the inner
surface of the cylinder, a cylindrical valve chamber being formed in the piston,
substantially as herein shown and described.
Dated this 98th day of November 1884