Improvements in Rotary Engines.
Year: 1899

page_text: Date of Application, 10th Jan., 1899- Accepted, 6th May, 1899
COMPLETE SPECIFICATION.
Improvements in Rotary Engines.
We, ELTON PRESTON KENDALL, of Fairlee, Marble and Granite Worker, ELGIN
DARIUS BURNES, of Chelsea, Hotel Keeper, GEORGE ASA DICKEY, of Bradford,
Lawyer, and CHARLES FOSTER SMITH, of West Topsham, Sheriff, all in Orange
County and State of Vermont, United States of America, do hereby declare the
nature of this invention and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
This invention relates to rotary engines of the concentric piston type, and has
for its object to provide a simple, compact, and efficient construction and arrange-
ment of valves and pressure-controlling devices, whereby the supply of motive-
agent is diminished as the operating piston-wing recedes from the fixed abut-
ment; and also to provide such a construction and arrangement of parts as to
provide for the use of either one or more piston-wings, as may be preferred, to
suit the conditions under which the mechanism is to be operated.
Further objects and advantages of this invention will appear in the following
description, and the novel features thereof will be particularly pointed out in
the appended claims.
In the drawing-
Figure is a central sectional view, taken in a plane transverse to the piston
axis, of an engine constructed in accordance with this invention.
Figure 2 is a side view showing the steam-chest and valve mechanism in
section, on a plane parallel with the spindle of the balanced abutment.
Similar numerals of reference indicate corresponding parts in all the figures
of the drawing.
and
In a casing 1, having a cylinder portion 2, and a steam-chest 3, (or other
motive-agent chest,) is mounted a concentric rotary piston 4, of which a wing or
wings 5 may be so fitted with packing strips 6 as to form a steam-tight bearing
against the inner surface of the cylinder. Communicating with the cylinder is a
cavity 7 forming an abutment-seat, and mounted for oscillatory movement in
said seat is a balanced or double-winged abutment S, having an operating or
pressure wing 9 and a balancing wing 10, extending in approximately
opposite directions from the spindle 11
of approximately equal
areas. These abutment wings are also provided with packing-strips 6°
to bear against the wall of the seat, and in the path of the balancing-
wing 10 are arranged spaced stops 12 and 13, to respectively check
the movement of the abutment at the limits of its oscillation. The steam
chest 3 is provided with an inlet or supply port 14, and connecting the steam-
chest with an abutment-seat is a feed-port 15, also forming a seat for a slide or
reciprocatory valve 16. This reciprocatory valve performs the function of a
throttle, in that, being hollow or tubular, it is provided with a plurality of spaced
feed-ports 17, which are adapted to be successively closed as the pressure wing 9
is moved from its normal or extended position, shown in dotted lines at 19 in
Figure 1, to its retracted position, indicated in dotted lines at 20 in the same

page_text: figure, the closing of said ports 17 being accomplished by the sliding of the valve
into the seat 15. Connection is made between the inner end of the slide-valve
and the operative or pressure wing of the abutment, by means of a link 18, and
the inner end of the bore of the slide-valve is closed to form a head adapted to
receive the pressure of motive-agent entering the abutment-seat from the steam-
chest.
Inasmuch as the abutment is balanced, it will be seen that the pressure of
motive-agent in the abutment-seat, admitted through the ports 17, will not
materially affect the contact of the edge of the operative wing 9 with the surface
of the piston 4, and hence as the piston-wings successively approach the operative
wing of the abutment, they will serve to swing the abutment to its inoperative
position, indicated in dotted lines at 20 in Figure 1, in order that said wings
may pass, without encountering any material obstacle to the rotary movement
of the piston. But in order that the abutment may be returned promptly to its
operative position, after a piston-wing has passed the extremity thereof, I depend
upon the fluid pressure applied to the closed inner end or head of the tubular
slide-valve 16. Thus, as the piston rotates, its wing or wings periodically dis-
place the abutment by forcing it into the abutment-seat, and after the piston-
wing has passed the abutment the latter is returned to its operative position, in
order to allow the application of motive-agent to said wing of the piston, by the
continuous pressure which is applied from the steam-chest to the closed inner end
or head of the slide-valve.
It is desirable in mechanism of this class to provide means whereby the supply
of the motive-agent, when of an expansible quality, may be diminished as the
piston-wing, which is receiving the pressure, recedes from the point of supply,
and in order to accomplish this I construct the surface of the piston with a
gradual cam-face extending from a point a (see Figure 1) to the crown or most
remote point b of the piston-wing. Hence, when the point a reaches the abut-
ment-wing, the latter begins to move gradually toward its rotracted position,
and thus the spaced feed-ports 17 are successively advanced into the seat 15, and
are closed, whereby the steam or other motive-agent enters the abutment-seat
through a gradually reduced feed-port. This reduction of the inflow of motive
agent continues until, the piston-wing having reached a point in the plane of
the operative wing 9 of the abutment, the inlet of steam is entirely cut off.
the same way, after the piston-wing has passed the abutment-wing, the applica-
tion of the motive-agent is made gradually, in that the feed-ports 17 are suc-
cessively exposed.
In
The engine which I have illustrated in the drawing is provided with a piston
having two wings, but, as above indicated, the number of wings may be varied,
and also a duplication of the valve and abutment mechanism may be provided
to adapt the structure for imparting rotary motion in either direction to the
piston and in the same way a plurality of pistons and valve mechanisms may
be arranged in series in the same casing to form either a double, triple, or quad-
ruple engine, but I have deemed it unnecessary, in view of the fact that such
changes would involve mere duplication, to illustrate the same in the drawings.
Also, various other changes in the form, proportion, and the minor details of
construction may be resorted to without departing from the spirit or sacrificing
any of the advantages of this invention.
The position occupied by the pressure wing when at the extreme end of its
downward stroke is such that the pressure wing fits tightly upon the surface
of the piston 4 as shown in dotted lines at 19 in Figure 1. This part of the sur-
face of the piston is cylindrical and touches the imaginary cylindrical surface
formed by the rotation of the contact edge of the pressure wing. This cylindrical
portion of the surface of the piston extends up to the point marked "a" in
Figure 1. It will thus be seen that as the piston rotates there will be a tight
joint formed between the pressure wing and the piston by means of the packing
strips 6. When the point a reaches the pressure wing the latter will be

page_text: gradually moved towards its retracted position as hereinbetore explained, a tight
joint being maintained until the point "b" meets the pressure wing.
The exhaust port of my engine is shown at 21 Figure 1. It will be seen that
when the piston is in the position shown in the drawing the motive fluid exhausts
freely through the said port and will continue to do so until the end 22 of the
piston has come round and cleared the port; no further exhaust is then necessary
since the space previously exhausted is now practically at atmospheric pressure.
Having now particularly described and ascertained the nature of our said in-
vention and in what manner the same is to be performed, we declare that what
we claim is: -
1. In a rotary engine, the combination of a casing having a cylinder and a
communicating abutment-seat, a winged piston mounted in the cylinder, an
oscillatory balanced abutment mounted in said abutment-seat and having a wing
arranged in operative relation with the piston, and in the path of the piston-
wing for displacement thereby, and yielding abutment-operating means for ex-
tending the abutment-wing after each displacement by a piston-wing and con-
trolling cylinder feed ports through which motive-agent is admitted to the abut-
ment-seat in advance of the operative abutment wing, substantially as specified.
2. In a rotary engine, the combination of a cylinder and a communicating
abutment-seat, a winged piston mounted in the cylinder, an oscillatory abutment
having oppositely located operative and balancing wings of approximately equal
areas, the operative abutment-wing being arranged in the path of the piston-
wings for displacement thereby, and a reciprocatory abutment-operating member
exposed to a constant yielding pressure, for extending and maintaining the
operative wing in its normal position and controlling cylinder feed ports, sub-
stantially as specified.
3. In a rotary engine, the combination with a cylinder and a communicating
abutment-seat, of a winged piston arranged in the cylinder, an oscillatory winged
abutment arranged in the abutment-seat and having approximately co-extensive
operative and balancing wings simultaneously exposed to fluid pressure the
operative abutment-wing being arranged in the path of the piston-wings for
displacement thereby, and a slide valve permanently exposed to fluid-pressure,
connected with the oscillatory abutment for normally maintaining the same in
its operative position, and controlling cylinder feed ports, substantially as
specified.
4. In a rotary engine, the combination with a cylinder and a communicating
abutment-seat, of a winged piston arranged in the cylinder, an oscillatory
winged abutment arranged in the abutment-seat and having approximately co-
extensive operative and balancing wings simultaneously exposed to fluid pres-
sure, the operative abutment-wing being arranged in the path of the piston-
wings for displacement thereby, and a hollow slide-valve connected with the
abutment and fitted in an inlet-port for the communication of motive-agent to
the abutment-seat, said slide-valve having lateral feed-ports for closure by the
axial movement of the valve, substantially as specified.
5. In a rotary engine, the combination with a cylinder and a communicating
abutment-seat, of a winged piston arranged in the cylinder, an oscillatory winged
abutment arranged in the abutment-seat and having approximately co-extensive
operative and balancing wings simultaneously exposed to fluid-pressure, the
operative abutment-wing being arranged in the path of the piston-wings for dis-
placement thereby, and a hollow slide-valve fitted in an inlet-port and connected
with the abutment, said valve having a head exposed to the constant pressure
of motive-agent admitted through the inlet-port, and provided with lateral feed-
ports for closure by the 'walls of the inlet-port when the valve is moved axially,
substantially as specified.
6. In a rotary engine, the combination with a cylinder and a communicating
abutment-seat, of a winged piston arranged in the cylinder, an oscillatory winged

page_text: abutment arranged in the abutment-seat and having approximately co-extensive
operative and balancing wings simultaneously exposed to fluid-pressure, the
operative abutment-wing being arranged in the path of the piston-wings for
displacement thereby, and a hollow slide-valve fitted in an inlet-port in communi-
cation with said abutment-seat and flexibly connected with the abutment, said
slide-valve having a head permanently exposed to the constant pressure of motive-
agent admitted through the inlet-port and provided with a longitudinal series
of feed-ports, for successive closure by the walls of the inlet-port as the valve is
moved axially, substantially as specified.
7. In a rotary engine, the combination of a casing having a cylinder, a com-
municating abutment-seat, and an inlet-port in communication with the abut-
ment-seat, a winged rotary piston mounted in the cylinder, a winged abutment
mounted for oscillation in the abutment-seat and having oppositely-extending
approximately co-extensive wings, of which one is arranged in operative relation
with the piston, a hollow slide-valve fitted in said inlet-port and provided with a
plurality of feed-ports arranged in a longitudinal series, for successive closure and
exposure by the opposite reciprocatory movements of the valve, and connections
between the abutment and said valve, substantially as specified.
S. In a rotary engine, the combination with a casing having a cylinder and a
communicating abutment-seat, a winged piston mounted in the cylinder, a winged
abutment mounted in the abutment-seat, and a feed-valve operatively connected
with the abutment and having a plurality of spaced feed-ports arranged parallel
with the direction of movement of the valve, said feed ports being adapted for
successive closure and exposure during movements of the valve in opposite
directions, the piston having a gradual cam-face for actuating the abutment to
impart movement to the feed-valve, substantially as specified.
9. In a rotary engine, the combination of a casing having a cylinder and a
communicating abutment seat, and also having an inlet-port communicating
with the abutment-seat, a winged piston mounted in the cylinder, an oscillatory
abutment mounted in the abutment-seat and having oppositely disposed operative
and balancing wings, fixed stops arranged in the path of the balancing wing to
limit the oscillatory movement of the abutment, a hollow feed-valve fitted for
reciprocatory movement in the said inlet-port and provided with a closed inner
end or head and lateral feed-ports adapted to be enclosed within the inlet-port
when the valve is retracted, and connections between the abutment and the feed-
valve, substantially as specified.
Dated 1
101
1
1000