Improvements in Rotary Engines.
Year: 1898

page_text: Improvements in Rotary Engines.
I, JAMES YATE JOHNSON, of 47, Lincoln's Inn Fields, in the County of London,
Gentleman, do hereby declare the nature of this invention (which has been com-
municated to me from abroad by Montague James Bretherton, of Philadelphia,
County of Philadelphia, State of Pennsylvania, United States of America,
Mechanical Engineer, and Charles Herbert Silliman, of Fort Worth, County of
Tarrant, State of Texas, United States of America Banker), to be as follows:
The main object of this invention is to make a rotary engine steam tight and in
which the wear upon the parts will be automatically taken up; a further object
of the invention is to construct a cut-off valve for the engine which can be thrown
into and out of action; and a still further object of the invention is to construct
an accurate and simple reversing valve.
In this improved engine the casing is cylindrical and mounted within the said
cylinder is a bushing formed by two rings which accurately fit the cylinder and
the abutting edges of these rings are preferably notched so that the projections of
one ring will fit in the notches in the other ring, and mounted in grooves in the
abutting edges of the two rings is a metallic packing strip, at the back of which
is a yielding packing strip.
The driving shaft is mounted in bearings in the two heads of the cylinder and
these bearings are suitably packed so as to prevent leakage.
The piston wheel is preferably made in two parts and slotted for the reception
of the sliding pistons and this wheel has two flanges, one on each side, which ex-
tend beyond the edges of the bushing rings of the cylinder, so that the edges of
these rings will bear against the inside surface of the Hanges, thus making a steam
tight joint at these parts. The flexible packing within the rings tends to keep
the latter against the flanges of the piston wheel. These flanges are preferably
separate from the wheel and in the example now being described are in the form
of two rings secured to the wheel by bolts, and these flanges are grooved to allow
the sliding pistons to be guided not only by the hub of the wheel, but also by the
flanges.
The pistons are preferably made in two parts and their abutting edges arranged
in the same manner as the cylinder rings and mounted between the two sections
of each piston is a spring which forces these sections outwards against the flanges
of the piston wheel.
In each of the cylinder heads is an annular groove and in connection with each
piston is a rod, the ends of which fit into the said grooves and between the piston
and the rod are mounted springs: these grooves and rods tend to force the pistons
out against the rings of the cylinder so as to insure a steam tight joint at the outer
edges of said pistons and the springs between the rods and the pistons allow the
pistons to yield when necessary. A shoe is preferably provided on the piston so
that the latter will more accurately fit the cylinder.

page_text: The cylinder rings are split so as to allow for the insertion of an abutment at
the point where the hub of the piston wheel comes in contact with the cylinder,
and it will be understood that the shaft and the piston wheel are eccentric in re-
lation to the cylinder. This abutment fits into a block which is secured to, and
extends across the longitudinal split of, the two rings. The abutment as well as
the block is made in two parts movable laterally in the same manner as the cylinder
ring.
Above the cylinder and conveniently forming a part of the same casting there-
with, are two valve chambers, one the reversing valve chamber and the other the
cut-off valve chamber; these valve chambers are connected together by a steam
passage and the reversing valve chamber is connected to the cylinder at one side
of the abutment by a passage and the cut-off valve chamber communicates with the
cylinder on the other side of the abutment through another passage so that in
running forward the reversing valve is so set that the steam will enter the cut-
off valve chamber and pass thence through one port into the cylinder and exhaust
through the opposite port and reversing valve chamber.
The reversing valve comprises a plug flattened on one side and hollow at the
centre with side ports opening into the hollow centre; this hollow centre com-
municates with the exhaust pipe while the flattened part provides a steam space
which communicates with the steam inlet pipe so that by turning the valve in one
position this steam space is cut off from the port at one side and the exhaust is
open to this port while at the other side the exhaust is closed and the steam inlet
opened, by reversing the valve the inlets and outlets are reversed.
The engine can be either run under a full head of steam the full stroke or the
steam can be cut off and used expansively during a portion of the stroke; these
operations may be accomplished by providing the cut-off valve chamber with a
cut-off valve which can be operated so as to more or less close the port loading to the
cylinder, by means of an eccentric on the main shaft connected to a crank arm
on the valve stem, and by arranging the valve so that it can be lifted off its seat
by a hand lever so that when it is wished to run the engine with full steam pres-
sure the entire stroke, the hand lever is operated and the valve raised off its seat,
but when it is wished to run the engine with steam cut off at a portion of the
stroke, then the valve is allowed to seat itself and the eccentric will move it to
cut off at the necessary times. It will be understood that the cut-off valve can be
operated by an ordinary link motion.
Partly in the cylinder casing and partly in the rings at the steam inlet and
exhaust ports there are fitted tapered or dovetailed port plates, which while making
steam tight joints will not prevent the free lateral movement of the rings, and
channels are also cut in the rings leading from the ports to a point near the abut-
ments so as to prevent the pistons becoming locked on a dead centre when oue
of the pistons is between one of the ports and the abutment; by having the
channels cut in one of the rings steam is allowed to pass to the back of the pistons.
By employing two laterally movable rings lining the cylinder, flanged piston
wheels against the flanges of which the rings bear, laterally movable pistons
adapted to move radially in the piston wheel, and a laterally movable abutment
as herein before described, a practically steam tight rotary engine is obtained.
There may be mounted within the slots of the piston wheel in which the pistons
slide, packing strips adapted to press against the sides of the pistons as to prevent
leakage past the pistons.
late this with day of June 1400
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.

page_text: Improvements in Rotary Engines.
I, JAMES YALE JOHNSON, of 47, Lincoln's Inn Fields, in the County of London,
Gentleman, do hereby declare the nature of this invention (which has been com-
municated to me from abroad by Montague James Bretherton, of Philadelphia,
County of Philadelphia, State of Pennsylvania, United States of America,
Mechanical Engineer, and ('harles Herbert Silliman, of Fort Worth, County of
Tarrant, State of Texas, United States of America, Banker) and in what manner
the same is to be performed to be particularly described and ascertained in and
by the following statement:-
The main object of this invention is so to construct a rotary steam engine that
it will be steam tight and that the wear will be automatically taken up without
increasing the friction to a greater extent than in the ordinary reciprocating en-
gine. A further object of the invention is to so construct the valve mechanism that
it can be readily reversed even at full speed, and to throw into or out of action the
cut-off. And a still further object of the invention is to so construct the engine
that there will be no dead centres.
I will describe the invention by reference to the accompanying drawings in
which;
-
Figure 1 is a perspective view illustrating the improved rotary engine provided
with link motion;
Figure 2 is a side view of the improved engine with the cap or cover removed;
Figure 3 is a sectional view;
Figure 4 is a section on the line 4-4, Figure 2;
Figure is a perspective view of the engine casing;
Figure 6 is a perspective view of the piston wheel and flanges detached;
Figure 7 is a perspective view of one of the sliding pistons;
Figure 8 is a longitudinal sectional view of one of the pistons;
Figure 9 is a transverse sectional view of the same;
Figure 10 is a detached perspective view of the reversing valve;
Figure 11 is a detached perspective view of the cut-off valve;
Figure 12 is a perspective view of one of the port plates;
Figures 13 and 14 are enlarged detached views shewing details of the cylinder
rings; and
Figure 15 is a detached perspective view of one of the packing strips for the
piston.
A is the casing of the improved rotary engine; this casing has an extension A¹
forming the reversing valve chamber and an extension A forming the cut-off
valve chamber. The cut-off valve chamber is connected to the cylinder by a pas-
sage a and the reversing valve chamber is connected to the cylinder by a passage
a and the two chambers A¹ As are connected together by a passage a².
is a steam inlet into the reversing valve chamber, said inlet being connected
with the steam supply pipe which, as ordinarily, is provided with a throttle valve.
at is the exhaust, which, in the example shewn in the drawings is provided in the
rear cap of the reversing valve chamber.
B is the shaft of the engine, which is mounted in suitable bearings b on heads
or covers 11 secured to the cylinder casing A. These heads or covers form the
side walls of the chamber in which the piston wheel rotates; the bearings bare in
the form of glands, and steam is prevented from escaping between the bearings
and the shaft B by suitable packing, so that while the shait is free to revolve
within its bearings the steam cannot escape at the said bearings.

page_text: Secured to the shaft B is a piston wheel 1), which in the example illustrated in
the drawings is made in two sections secured together by bolts, but in other in-
stances, this piston wheel may be made in one, or three or more pieces as desired.
The shaft B is eccentric to the bore of the cylinder and the piston wheel is so
proportioned that it will snugly fit against the upper portion of the cylinder, as
indicated in Figure 2, and the passages a a¹ are arranged respectively on either
side of this point of contact and when the engine is running forward the passage
a serves as the steam inlet passage, and the passage a¹ serves as the steam outlet
passage. At the point where the piston wheel comes in contact with the cylinder
is an abutment block E².
Lining the cylinder are two rings or bushings E, E', these rings snugly fit the
cylinder casing and each ring has a series of projections e which fit in recesses of
the other ring, so as to form a joint, as shewn in Figures 5 and 14.
There is an annular groove cut in the projections e, and in the groove in each
head is inserted a lead stripe which is secured to one section and is free in the
other. Between the lead strip and the bottom of the groove in the ring to which
the lead strip is not attached is placed a suitable packing ring which tends to
force the rings E E' apart.
On the piston wheel are flanges D¹ which extend beyond the rings or bushings
EE of the casing, so that as the rings E El are forced outwards by the packing
e, as before mentioned, they will bear against, and make tight joints with the
inner surfaces of these flanges 1) the meeting surfaces of the rings EE' and
flanges being ground for obtaining the said tight joint.
If desired, springs may be inserted between the two rings EE to press them
always into close contact with the flanges 1 though the packing e is preferred for
this purpose.
The abutment block E2 is made in two pieces e¹, one tongued into the other,
and in one of these sections is a cavity or recess for the reception of a coiled spring
e3, which tends to keep the outer ends of the sections against the piston-wheel
flanges D, and in the upper portion of the abutment block E are cavities for
the reception of coiled springs e³, which tend to keep the block in contact with
the periphery of the piston wheel. The abutment block 2 engages with a con-
necting block E³ fitted in the cylinder casing and secured to the rings E E¹.
The ports a a are some little distance from the abutment block E2 and each
extends through a tapered plate or key F2 which is undercut, as shewn in the
perspective view Figure 12, and is adapted to seat itself partly in the casing and
partly in recesses in the rings EE'; this tapered plate or key is driven into place
in the casing, but it fits freely in the recesses in the rings so as to allow for the
free lateral movement of the rings. These plates or keys have openings to allow
for the passage of the steam to and from the cylinder and serve to make steam
tight joints at the ports.
The flanges of the piston wheel are, by preference, made separate from the wheel
and are secured rigidly to the wheel by screws or bolts. The flanges are in the
form of rings reduced in thickness, so that they will extend over the edges of the
piston-wheel and form tight joints, and they are also grooved at d¹
in line with the radial slots d in the piston wheel, in which the
piston blades F slide. These blades, therefore, are not only guided by
the hub portion of the piston wheel but are also guided by the flanges D¹ so that
the strain is more evenly divided than where the piston blades are simply guided
by the hub.
Each of the piston blades F is made in two sections f which preferably have
their abutting edges notched in the same manner as the rings E E¹ of the cylinder,
with stopping plates f extending across the joints, to admit of the blade-sections
moving apart in the direction of the axis of rotation.
Springs fare placed in cavities in the piston sections f, to force the pistons
against the flanges of the piston wheel, and preferably secured to the outer end
of each section are hardened bearing plates f³ which fit snugly in the grooves d¹
of the flanges D¹.

page_text: The back or inner portion of each piston blade is slotted at f³ and arranged in
the slot is a rod F¹, the ends of which rest in grooves in the cylinder heads B¹;
these grooves are shaped as shewn, so that the rods force the piston blades out into
contact with the rings E E¹ of the cylinder. Springs f are placed within recesses
in the sections of the piston blades, and the pressure is applied through these
springs to the blades, so that they will readily yield but will always be in contact
with the surface of the rings.
A shoe fo is preferably provided for each piston blade; this shoe is slipped on
the undercut semi-circular projection so that it will have free movement to seat
itself properly on the ring, but its movement is limited so that it cannot possibly
move out of place. It is kept longitudinally in place by the hard metal bearing
pieces. In some instances this shoe may be dispensed with, but its use is pre-
ferred on engines of large size.
Resting in recesses dat each side of each piston blade are blocks which are
pressed against the surface of the piston blades by flat springs Figure 15, so as
to prevent leakage of steam past the piston.
The piston wheel is made in two parts as shewn in Figure 6, so that the slide-
ways for the piston blades as well as the recesses for the packing strips d³ can be
readily formed.
As shewn in Figure 3, grooves et are preferably formed between the ports a a¹
and the abutment block E, so as to prevent the shaft remaining on a dead centre.
If, for instance, without the grooves d', one of the pistons should stand between
one of the ports and the abutment block, the engine would not start without the
shaft being first turned, but by making the grooves e as indicated, steam passes
to the back of the piston in proximity thereto and operates the engine.
A cut-off valve is preferably arranged in the steam port and this valve can be
raised off its seat so that the steam will be admitted to the cylinder during the
full stroke of the piston. When the valve is on its seat the steam is cut off at a
certain portion of the stroke according to the amount desired and the shape of the
valve.
The valve I fits within its casing A2 and has a groove throughout its length in
which is mounted the operating spindle i which has a crank arm at its outer
end, which may be connected to an eccentric on the shaft B of the engine, either
directly, or indirectly through link motion, as shewn in Figure 1.
The groove in the valve I is of such a depth that the valve can be raised off its
seat; to accomplish this two yokes are formed on the valve and the stem J ex-
tending down through an opening in the valve casing A2, has a T-head ; which
engages with the yokes 22. The upper end of the stem J is connected to a lever
J pivoted at j¹ to a standard and having a movable locking arm which, when
down, as shewn in Figure 5, holds the lever up and also holds the valve off its seat,
so as to allow the steam to flow into the cylinder throughout the full stroke of the
engine, but by releasing the lever J¹ the valve will descend on to its seat and will
again cut off the steam in the manner herein before described.
Within the valve casing A' is a reversing valve K flat on top as shewn in the
perspective view, Figure 10, and hollow as shewn in the sectional view, Figure 3.
The valve K has ports & leading to the central chamber K¹, so that when the valve
is in one position the engine will take steam over the top of the valve through
the passage a, valve chamber A2 and passage a, and it will exhaust through the
passage a and the interior K¹ of the valve K to the exhaust pipe.
the valve K into its second position the steam will be admitted through the pas-
By turning
age al to the opposite side of the pistons and consequently the engine will be ro-
ated in the opposite direction, but when so reversed the cut-off mechanism shewn
n the drawings is not available for using the steam expansively, it being neces-
ary, should this expansive use of the steam be required, to provide a second cut-
ff mechanism in the passage a¹.
While the invention has been described as using steam it will be understood
hat any fluid under pressure may be used.

page_text: Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I declare that what I claim is; -
1. In a rotary engine the combination of a flanged piston wheel, a casing, and
two bushing rings fitted in the casing and resting against the flanges of the piston
wheel, substantially as herein before described with reference to the accompanying
drawings.
2. In a rotary engine the combination with a casing, a flanged piston wheel and
two bushing rings fitted in the casing, of means for separating the rings and
pressing them against the inner surfaces of the flanges of the piston wheel, sub-
stantially as herein before described with reference to the accompanying drawings.
3. In a rotary engine the combination with a casing and a flanged piston wheel
therein of two rings mounted within the casing and notched on their inner edges,
the notches of one ring engaging with the recesses of the other, each ring having
an annular recess in its inner edge, and a ring, and packing fitting in the annular
recesses, so as to form a yielding steam tight joint, substantially as hereinbefore
described with reference to the accompanying drawings.
4. In a rotary engine the combination with a casing, and a flanged and slotted
piston wheel therein, of piston blades fitted in the slots, each such blade being
made in two sections, and having means whereby the said sections are pressed
against the flanges of the piston wheel, substantially as hereinbefore described
with reference to the accompanying drawings.
5. In a rotary engine the combination of a casing, two bushing rings laterally
movable, within the casing, a two-part piston wheel slotted to receive piston
blades, flanges secured to each end of the piston wheel, grooves in the said flanges
in line with the slots in the piston wheel, piston blades in the said grooves and
slots, each blade made in two relatively-adjustable parts, and means for positively
moving the blades radially, substantially as herein before described with reference
to the accompanying drawings.
6. In a rotary engine the combination of a cylinder having inlet and outlet
ports therein, an abutment block between the ports, two bushing rings within the
cylinder, the said rings being grooved to near the abutment block, and a piston
wheel and pistons, substantially as and for the purpose herein before described
with reference to the accompanying drawings.
7. In a rotary engine the combination with a cylinder having a piston wheel
and pistons therein, a valve casing, a cut-off valve and means for oscillating the
same of means for raising the valve off its seat so as to allow steam to enter the
cylinder during the full stroke, substantially as hereinbefore described with
reference to the accompanying drawings.
8. In a rotary engine the combination of a cylinder and pistons therein, a valve
casing, a grooved cut-off valve therein, an operating rod fitting the groove of the
valve, means for rocking said rod and oscillating the valve over the valve port,
a yoke on the valve, a rod having a T-head engaging with the yoke and means for
moving the said rod so as to elevate the valve off its seat, substantially as herein-
before described with reference to the accompanying drawings.
9. In a rotary engine the combination of a casing, laterally movable rings
within the casing, a flanged piston wheel, a shaft on which the piston wheel is
mounted, the flanges of said wheel overlapping the rings of the casing so as to
make steam tight joints, pistons arranged to slide in the piston wheel, each of
said pistons being made in two relatively-movable parts, a shoe mounted on each
piston, a connecting block in the casing, an abutment block made in two sections
and engaging with the connecting block of the casing, said abutment block being
movable so as to make steam tight joints, substantially as hereinbefore described
with reference to the accompanying drawings.
10. In a rotary engine the combination with a cylinder having closed ends, and
a bushing ring formed of endwise movable sections, of a rotary piston wheel carry-
ing pistons and having fixed thereto flanges contiguous to the edges of the said

page_text: bushing ring and pistons and overlapping the joint between the pistons and bush-
ing ring, said parts enclosing two or more steam spaces, substantially as herein-
before described with reference to the accompanying drawings.
11. In a rotary engine, a cylinder having closed ends, a bushing ring and abut-
ment and connecting blocks within the cylinder, a rotating piston wheel provided
with pistons and fixed flanges overlapping the edges of the pistons, said bushing
ring, and abutment and connecting blocks being made in sections movable end-
wise of the cylinder, substantially as herein before described with reference to the
accompanying drawings.
12. In a rotary engine, a cylinder having closed ends and a steam inlet, an ex-
pansible section bushing ring fitting within the cylinder, and a rotating piston
wheel provided with pistons and fixed flanges overlapping the edges of the ring,
the said wheel, flanges, ring and pistons enclosing a steam-tight chamber or steam-
tight chambers, substantially as hereinbefore described with reference to the ac-
companying drawings.
13. In a rotary engine, a cylinder, a piston formed of interlocking toothed
sections movable endwise, springs to press the said sections apart, and a plate ex-
tending through the interlocking portions of the toothed sections substantially as
hereinbefore described with reference to the accompanying drawings.
14. In a rotary engine, a cylinder, a piston formed of interlocking toothed
sections movable endwise, springs to press the sections apart and a plate extending
through the interlocking portions of the toothed sections, said springs pressing on
one of the sections and on the plate, substantially as hereinbefore described with
reference to the accompanying drawings.
15. In a rotary engine the combination of a flanged piston wheel, sliding piston
blades therein made in sections, springs tending to separate the sections, and
spring bars mounted in the wheel and adapted to rest against the faces of the
piston blades, substantially as hereinbefore described with reference to the accom-
panying drawings.
16. In a rotary engine the combination of a casing, guide slots in the casing,
a piston wheel, a blade therein, said blade being slotted longitudinally, a bur
passing through said slot and extending into the guide slots of the casing, and
springs within the blades bearing against the bar and tending to force the blade
out of the piston wheel, substantially as hereinbefore described with reference to
the accompanying drawings.
17. In a rotary engine the combination of a casing, two bushing rings within
the casing, a two-part recessed connecting block fitted in the casing and rings, a
two-part abutment block in the recess of the connecting block, springs tending to
separate the two parts of the abutment block, a piston wheel and springs between
the abutment and connecting blocks tending to force the abutment block against
the piston wheel, substantially as hereinbefore described with reference to the
accompanying drawings.
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C T1
1000
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.