Improvements in Rotary Engines.
Year: 1899

page_text: Date of Application, 11th Sept., 1899-Accepted, 30th Dec., 1899
10
COMPLETE SPECIFICATION.
Improvements in Rotary Engines.
We, ALBERT WIDMAN and JOHN CHRISTOPHER BAKER, both of No. 603 Central
Avenue, Connersville, in the State of Indiana, in the United States of America,
Gentleman, 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 ;-
Our invention relates to rotary engines, and has for its object to provide a
simple and compact construction and arrangement of parts whereby an economi-
cal application of motive-agent may be applied to the wings of a rotary piston;
to provide a simple and readily adjustable construction and arrangement of
piston-wings and means for folding the same successively as they pass the inlet-
port of the casing; and, furthermore, to provide a simple arrangement of valve
mechanism for controlling the admission of motive-agent and securing the de-
sired expansive action thereof upon the piston.
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 drawings-
Figure 1 is a side view of an engine constructed in accordance with our
invention.
Figure 2 is a central sectional view of the same taken in a plane perpendi-
cular to the axis of the piston.
Figure 3 is a central sectional view taken in a plane parallel with the axis
of the piston.
Figure 4 is a detail sectional view of a portion of the piston.
Figure 5 is a detail view in perspective of one of the piston-wings.
Similar numerals of reference indicate corresponding parts in all the figures
of the drawings.
Rising from a suitable base 1 are pedestals 2, at the upper ends of which are
arranged bearings 3 for the piston-shaft 4, and secured to said piston-shaft is
a piston-core 5, operating in a casing consisting of a cylindrical wall 6. and
opposite parallel heads 7. The engine embodying our invention is of the con-
centric piston type, wherein a cylindrical piston-core 5 operates concentrically
in the casing, and carried by this piston-core are radially reciprocatory wings 8
fitted in radial seats 9, and yieldingly held extended by means of springs 10.
We preferably dispose the springs, which are of the coiled type, concentric with
guide-pins 11 fixed to the piston-core at the inner ends of the seats 9, and
extending outwardly into guide-openings 12 in the wings. Extending rear-
wardly from each piston-wing is a web 13, having a rearwardly and inwardly
inclined outer edge forming a cam-face which, in the extendel position of the
wing extends approximately from the outer edge of the wing to the cylindrical
surface of the piston-core, and in large engines we preferably dispose a guide-
pin 14 in operative relation with this web to operate in a guide-opening 15,
and embraced by a coiled spring 16 for advancing the web outwardly with the
037

page_text: wing, to prevent cramping or binding, such auxiliary pin 14 and co-operating
spring 16 being illustrated in the drawings.
Secured to the opposite side surfaces of the piston-core are side plates 17,
of a diameter greater than the steam-chamber of the cylinder, and having an
interlocking connection with the cylindrical wall of the casing, said side plates
or disks being rabbeted, as shown at 18, to fit in rabbets formed in the
cylindrical wall 6, with the outer surfaces of said disks in contact
with the inner surfaces of the cylinder heads 7. These disks may
be secured by any suitable means to the piston-core, as by screws 19, and they
form not only the means for maintaining the piston in a truly alined position
with relation to the cylinder and relieve the piston-shaft 4 of a large proportion
of the transverse strain due to the operation of the mechanism, but they serve
to prevent leakage of the motive-agent by reason of the interlocking joint
between their peripheries and the cylinder wall. The disks 17 are provided in
their inner or facing surfaces with guide-grooves 20 alined with the piston-
wing seats 9 to receive the lateral edges of the piston-wings, and thus insure
the accurately alined radial reciprocation of said wings.
In the construction illustrated, the piston-shaft is shown extending outwardly
through bearing-blocks or brasses 21 in the cylinder heads, and a belt or fly-
wheel 22 may be attached to said shaft, as in the ordinary practice.
Communicating with the steam-chamber of the chamber of the cylinder is an
inlet or feed-port 23, and contiguous thereto is the abrupt end of a piston-wing
folding-cam 24, which tapers rearwardly from the inlet-port to. a point approxi-
mately diametrically opposite to said port, where the surface thereof merges
into that of the cylindrical wall of the casing. The surface of this cam is
tapped at an intermediate point for communication with an exhaust-port 25,
and also, at a point near the abrupt end, for communication with a relief or gage-
cock 26, and at its abrupt end the cam is provided with an anti-friction bearing-
roll 27 for contact with the peripheral surface of the piston-core and the upper
or outer edges of the piston-wing webs.
The inlet-port 23 communicates with a valve-casing in which is arranged an
oscillatory or rocking-valve 28 exposed to the pressure of motive-agent, such
as steam, admitted through the supply-port 29 and thereby held in efficient
contact with the valve-seat. Said valve is loosely connected for radial movement
with the cross-sectionally angular valve-stem 30 mounted in the horizontally-
alined bearings in the ends of the casing, and to one exposed extremity of said
valve-stem is attached a crank-arm 31 from which extends an eccentric-rod 32
and an eccentric strap 33 encircling an eccentric 34 on the main or piston-
shaft 4. In order to vary the throw of the valve, to secure, to a greater or less
extent, the effect of the expansive force of the motive-agent, an adjustable con-
nection is formed between the eccentric-rod and the crank-arm, such connection,
in the construction illustrated, consisting of a slot 35 engaged by a pivot-
bolt 36.
In operation the steam or other motive-agent is admitted at intervals con-
trolled by the oscillation of the cut-off valve to act upon the rear or webbed
surfaces of the piston-wings, back pressure of the steam or motive agent being
received by the abrupt end of the cam 24, which constitutes a fixed abutment.
As a wing traverses the surface of the cam 24 it is repressed in opposition to the
tension of the extending spring 10, and also of the auxiliary spring 16 when the
latter is employed, and after said wing passes the exhaust-port 25, all of the
steam or motive-agent remaining in the steam-chamber is compressed and forced
into the steam-chamber in advance of the fixed abutment, the relief-cock 26
being employed to ascertain the amount of compression. After the wing passes
the fixed abutment, it is extended by the force of its actuating springs, and the
rapidity of extension is controlled by the cam-faced web 13 with the anti-friction
bearing-roll 27, to avoid jar or other irregularity of motion.
It will be understood that by reason of the specific construction, particularly

page_text: 5
0
45
50
anu
ith reference to the interlocking connection between the piston-disks
he walls of the casing or cylinder, the necessity for a plurality of stuffing-boxes
avoided. Hence, in practice we preferably arrange simple bearing brasses 21,
s herein before described, in the heads of the cylinder to receive the wear of
he piston-shaft, said brasses being adapted, by any suitable means, for adjust-
The only stuffing-box which is in-
ment, to take up lost motion due to wear.
lispensable in connection with the apparatus as described is that shown at 37,
through which extends the valve stem.
Furthermore, the specific construction and arrangement of the piston-wings
and guiding and controlling webs provide for accuracy of movement and prevent
binding during rapid operation, and thus add materially to the efficiency of the
device.
Furthermore, the compression of steam or air, in advance of a piston-wing,
between the exhaust-port 25 and the gage-cock 26, serves to prevent waste or
leakage of pressure rearwardly beyond the roller 27, and by opening the cock,
the operator may ascertain whether there is any loss of pressure at this point.
A tight contact between the piston-core and roller 27, cannot be provided,
because allowance must be made for expansion of the metal by heat.
Various 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.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. In a rotary engine, the combination with a piston-core, of spring-extended
wings mounted upon the core and provided with rearwardly-extending cam-
faced webs for traversing a fixed bearing object, whereby the extension of a wing,
after passing a fixed abutment, is accomplished gradually, substantially as
specified.
2. In a rotary engine, the combination with a piston-core provided with. radial
seats, of piston-wings, provided with extending springs, and having rearwardly-
extending cam-faced webs, and a permanently-located bearing-roll arranged con-
tiguous to the fixed abutment of the engine cylinder, to traverse the cam-faces
of the piston-web and allow the gradual extension of the wings after passing
the abutment, substantially as specified.
3. In a rotary engine, the combination with a casing having a fixed abutment
and a rearwardly extending piston-wing repressing-cam, of a piston-core having
seats, spring-actuated wings mounted in said seats, and webs extending rear-
wardly from the piston-wings and having diagonally-disposed cam-faces for
traversing a bearing-roll located in the plane of said fixed abutment, substan-
tially as specified.
4. In a rotary engine, the combination with a casing having a fixed abutment,
and a rearwardly-extending piston-wing repressing-cam, and valve mechanism
for controlling the inlet and exhaust of motive-agent, of a piston-core, piston-
said core for radial extension and provided with rear
wings mounted upon
wardly-extending webs having diagonally-disposed outer cam-faces for traversing
a bearing-roll in the plane of said fixed abutment, and extending springs ar
ranged respectively under the piston-wings and their webs, substantially a
specified.
5. In a rotary engine, the combination with a casing having a cylindrical wal
and attached heads, and valve mechanism for controlling the inlet and exhaus
of motive-agent, of a piston having a core, disks secured to opposite sides of th
piston-core and bearing against the inner surfaces of the cylinder-heads, yield
ingly-extended piston-wings mounted in radial seats in the piston-core and havin
their side edges fitted in alined guides in the inner or facing surfaces of sai
55 disks, and means for repressing the piston-wings at intervals, substantially a
specified.

page_text: 6. In a rotary engine, the combination with a casing having a cylindrical
wall and heads, and valve mechanism for controlling the inlet and exhaust of
motive-agent, of a piston having a core, disks secured to opposite sides of the
core in contact with the inner surfaces of the casing-heads, and having an inter-
locking peripheral bearing upon the cylindrical wall of the casing, to form a
steam-tight joint, and piston-wings mounted in alined radial guides in said piston-
core and disks, and provided with yielding actuating devices whereby they are
normally held extended, and means for repressing the piston-wings at intervals,
substantially as specified.
7. In a rotary engine, the combination with a casing provided with spaced
inlet and exhaust ports, and valve mechanism for controlling the admission of
motive-agent to the inlet-port, a fixed abutment and a rearwardly tapering
piston-wing repressing-cam, of a piston having a core and yieldingly-extended
wings for co-operation with said repressing-cam of the casing, and a relief or
gage-cock communicating with the steam-chamber of the cylinder between said
fixed abutment and the exhaust-port, substantially as specified.
8. In a rotary engine, the combination of a casing having inlet and exhaust
ports, a piston having wings and means for repressing the same at intervals to
pass a fixed abutment in the casing, of a valve-casing, a rocking valve-stem mounted
in the walls of the casing and having a cross-sectionally angular body-portion,
a rocking cut-off valve fitted upon said body-portion of the valve-stem for radial
pressure by the contents of the valve-casing, to maintain said valve seated, a
crank-arm attached to one end of the valve-stem, and operating connections
between the piston-shaft and said crank-arm, for imparting an oscillatory move-
ment to the latter, said connections including a rod, and means for securing the
extremity thereof at different adjustments upon the crank-arm, substantially
as specified.
For the Applicants.
J. G. LORRAIN, M.I.E.E., M.I. Mech. E.,
Norfolk House, Norfolk Street, London, W.C., Chartered Patent Agent.