Improvements in Rotary Engines.
Year: 1888

page_text: Date of Application, 29th Dec., 1888
Specification Accepted, 16th Mar., 1889
Improvements in Rotary Engines.
A communication from CHARLES FREDERICK FOGG, of the City, County, and State of
New York, United States of America.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex
M.I.M.E. 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:-
The object of the invention is to provide a new and improved rotary engine which
is simple and durable in construction and very effective in operation, utilizing the
steam to the fullest advantage, at the same time being easily reversed.
The invention consists of a revolving disc secured to the main driving shaft and
carrying one, two or more sets of cylinders, each set consisting of two cylinders
placed diametrically opposite each other and connected with each other by a piston rod
carrying a cross-head held to slide on a fixed pin arranged eccentrically to the said
revolving disc, and of a steam chest. formed on the bearing of the disc and connected
by suitable ports with the sets of steam cylinders.
The invention also consists of certain parts and details and combinations of the
same, as will be fully described hereinafter.
Reference is to be had to the accompanying drawings forming a part of this specifi-
cation, in which similar letters of reference indicate corresponding parts in all the
figures.
Figure 1 is a front elevation of the improvement.
Figure 2 is a sectional end elevation of the same on the line of figure 4.
Figure 3 is a like view of the same on the line y-y of figure 4.
Figure 4 is a sectional end elevation of the improvement on the line z-z of
figure 1.
Figure 5 is a side elevation of the disc bearing and steam chest ; and
Figure 6 is a sectional elevation on of part of figure 5, showing part of the disc in
section.

page_text: On a suitably constructed frame A is mounted to rotate the main driving shaft B
provided with a driving pulley C for transmitting the rotary motion of the shaft B.
The front end of the shaft B is provided with a head Blaving lugs B³ fitting in
corresponding recesses formed in the front end of the disc D, so that when the latter is
rotated it also rotates the shaft B. The disc D is mounted to turn on a conical hub E
secured to one of the standards of the frame A, and on the top of the said conical
bub E is formed a steam chest F provided with a steam inlet pipe G and also
provided with a slide valve El adapted to open and close alternately the live steam
ports a and b extending inward in the hub E from the interior of the steam chest 1.
A suitable mechanism I is used for moving the said slide valve H over the
respective ports a and whenever the operator desires to reverse the engine. It is
understood that when one of the ports a or bis opened, the other port is closed and
.
vice versa..
On the disc D are secured one, two or more sets of cylinders J, J', and K, K1, the
cylinders of each set being placed diametrically opposite each other as is shown in
Figures 1 and 4. In the cylinders J, J', operate the pistons Land L' respectively.
connected with each other, by a piston rod I carrying in its middle a cross head La
provided with a slot I extending at right angles on each side of the piston rod 1.
The cylinders K, and K are provided with pistons N and N respectively; connected
with each other by piston rod N also provided in its middle with a crosshead N3
having a slot N extending at right angles to the piston rod N. Thus the two cross
heads Land N³ are held at right angles to each other, one in front of the other. so
that a pin O extends into the slots L and N of the said cross-heads L³ and N³. The
pin O is secured to a standard P fastened on the main frame A, and the said pin
is held eccentric to the main driving shaft B, the distance between the axis of the
shaft B and the pin O being equal to one-half of the stroke of each of the
cylinders J, Jand N, N¹.
On the shaft B is coiled a spring R one end of which rests on the hub E, its other
end pressing against a collar S secured on the main shaft B. The spring R exerts a
pressure against the shaft B in the direction of the arrow u¹, so that the disc Dis
firmly held on its conical bearing or hub E, thereby forming a steam tight joint
between the said disc D and its bearing E.
In the outer end of the cylinder J is formed a port D which connects permanently
with a channel e formed in the disc D and extending to a port d formed in the inner
end of the cylinder J. A port fis formed in the inner end of the cylinder J and
connects permanently with a channel g formed in the disc D and extending to a
port formed in the outer end of the cylinder J. The channels e and g extend on
opposite sides of the hub or hearing E, as illustrated in figures 1 and 3.
In the outer end of the cylinder K is formed a port which registers permanently
with a channel i formed in the disc D and extending to a port formed in the inner
end of the cylinder K. In the inner end of the cylinder K is formed a port which
connects permanently with the channel leading to a porty formed in the outer end of
the cylinder K. The channels i and k extend at opposite sides of the hub E, and at
right angles to the channels e and g, as illustrated in Figures 1 and 3. The channel e
leads into a U-shaped channel e, opening at both ends into the conical aperture DI
which forms the bearing of the disc D on the hub E. The other channels g, and k
open into like U-shaped channels g, ¹, and ¹, also leading into the conical aperture D
of the disc D. The U-shaped channels eg and, are arranged opposite each
other as shown in figure 2, and the end openings of each of the said channels are
alternately opened and closed by the slides e, g, 1, and 2, respectively, so that
when one of the end openings of the respective channel is open, the other one is
closed by its corresponding slide and vice versa. The open end of each U-shaped
channel e, g, or k¹ registers alternately, at each revolution of the disc D, with the
open live steam ports a or b, and with the exhaust pipe c, formed in the hub E and
leading to an exhaust pipe c' extending to the outside in the usual manner. The live
steam 'port a extends from the steam chest F and opens into the periphery of the
hub E at a', near the inner end of the said hub E, and the other live steam port (

page_text: extends from the steam chest F and opens into the periphery of the hub E at near
the outer end of the said hub. The end openings a and b of the live steam
ports a and b are placed a short distance on one side of the horizontal central plane of
the hub E, as is plainly shown in figures 2 and 3. That is, the end opening a' of the
live steam port a is above the middle line of the disc D and the end opening of
the live steam port b is a like distance below the middle line.
From
The exhaust port c opens at c into the periphery of the hub E near the inner end
of the latter in a vertical plane with the end opening a of the steam port a.
the exhaust port e, near its end opening extends a continuation of the exhaust
port which opens into the periphery of the hub E at c³, which is in a vertical
plane with the end opening of the live steam port b.
The operation is as follows:-
As shown in figure 4, the live steam port is closed by the side valve H, while
the live steam port a is open, so that the steam entering the steam inlet pipe G
passes through the steam chest F and passes into the port a through the same,
and out of the latter at its opening a. The slides e,g, and are in their
outermost position, so that the innermost end openings of the U-shaped
channels eg, and register with the said end opening a', whereby the live
steam can pass alternately. into the channels e, k, g, and i, thus supplying the
respective cylinders J, J, K, K', with live steam. When the channel registers
with the end opening a', the live steam passes into the channel g, and from the
latter passes simultaneously to the ports fand in the cylinders J, J, whereby
the piston is moved outward and the piston L' is moved inward, so that the
piston rod I slides across the face of the disc D in the direction of the arrow t¹,
whereby the cross-head L³ forms a fulcrum point for the disc D at the pin O, so
that the said disc is rotated in the direction of the arrows, and a consequent
rotary motion is imparted to the main shaft B, which transmits its rotary motion
to the machinery to be driven.
'
As the disc D revolves, the inner end of the U-shaped channel is cut off from
the end opening a of the live steam port a, and when the said dise D has made
one-half of a revolution, and the pistons L and L' are at their outermost and inner-
most position, then the open end of the U-shaped channel gregisters with the end
opening of the exhaust port c, so that in the next half revolution of the disc D,
the steam in the cylinders and Jcan exhaust on the return stroke of the
pistons L and L', through the ports and, and the channel y through which
the steam originally entered. As soon as the channel y las cut off from the end
opening a of the live steam port a, the next following channel k connects by the
open end of its U-shaped channel with the said opening a' of the live steam
port a, so that the live steam from the steam chest F passes into the channel k
and to the inner end of the cylinder K and the outer end of the cylinder K' the
respective pistons N and N being in the same relative position as described in
reference to the cylinders J and J and as shown in figure 4. The steam will thus act
on the pistons N and N¹ and force the same outward and inward respectively whereby
a new impulse is given to the disc D in the direction of the arrows by the action of
its cross lead N³ on the eccentric pin O.
During one half of a revolution the steam entered through the channel into the
cylinders K K expanded forcing the pistons N and N to the end of their stroke after
which the channel k after its U-shaped connecting channel will register with the end
opening of the exhaust channel c', so that on the return stroke of the piston N
and N the steam will be exhausted through the same channel k the respective
ports and the exhaust port c. It is understood that the connection of the open
end of the channel g and the channel with the end opening a' of the live steam
port A takes place during one quarter of a revolution of the disc D. During the
hext quarter revolution of the disc D the open end of the U-shaped channel el
will connect in the same manner as above described in relation to the channels g'
and with the open end at of the live steam port a so that the steam enters in the
channel e and from the latter passes to the ports d and d¹ at the outer or inner ends

page_text: of the cylinders J and J¹ respectively. As the pistons L and L' in the cylinders J
and J have travelled to their outer or inner ends respectively the steam entering
through the said channel e and the ports d and d¹ will cause the return stroke of the
return pistons L and Las above mentioned. This return stroke takes place during
one-half revolution of the disc D from the time that the steam port g took steam from
the live steam port a as above mentioned.
The channel e for cutting off from the end a¹ of the live steam port a makes one-
half of a revolution and then connects with the end openings 2 of the exhaust
channel c.
When the disc-1) has made one-quarter of a revolution beginning at the
time when the channel e' registered with the end opening at of the live steam port a
then the open end of the U-shaped channel registers with the open end a¹ of the
live steam port a so that steam from the steam chest F passes into the channel i and
In the
through the outer and inner ends respectively of the cylinders K and K.
same manner as above described in reference to the cylinders J and J. Thus it will
be seen that cach set of cylinders after taking steam with one channel at the end
opening a of the live steam port a makes one-half of a revolution before the said
respective channel connects with the exhaust channel c and then at this time the other
channel of the same set of cylinders connects with the live steam port thus causing a
roturn stroke of the respective piston of the said set of cylinders. As the two sets
of cylinders J and J and K K are placed at right angles to each other it will be
seen that a new impulse is given to the disc D at every quarter revolution of
the same.
It will further be seen that the steam exerts its pressure on the two pistons of each
set of cylinders at the same time and as the said two pistons by their piston rod and
cross head and the eccentric pin O set on the disc in one direction the latter is
turned with twice the force that would be used if only one cylinder has been
employed.
When the operator desires to reverse the engine he turns the valve mechanism 1 so
that the slide valve H closes the live steam port a and opens the live steam port b.
The live steam now enters from the steam chest F into the port and passes to its
end opening where it comes in contact with the outer end of the respective
slide gori (see figure 6) so that the said slide is moved inward by the pressure
of the steam thereby closing the former open end of the U-shaped channel ek gl
or and opening the other end of the said respective channel. As the open ends a
and of the respective ports a and b are above and below the horizontal middle line
of the disc D as before described and shown in figure 5 it will be seen that the live
t
steam now passing from the live steam port through the open end of the
respective channels e¹ k'g' and will cause the disc 1) to rotate in the inverse direction
of the arrow s¹.
The above operation is repeated with the only difference that the live steam passes
through the port & its end opening and into the respective channels e¹and and the
exhaust takes place through the same channels registering with the open end of
the exhaust channel c. As the slides e² ² g² and are now in their innermost
position the end openings a and c are closed on the revolving movement of the disc D
by the said slides passing alternately over the said openings a¹ and c².
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1. In a rotary steam engine the combination with a disc secured to a driving shaft
of one two or more sets of cylinders each set consisting of two cylinders placed
diametrically opposite each other on the said disc the cylinders of each set being
connected by pistons and a piston rod carrying a cross head and a fixed pin held
eccentric to the centre of the said dise said pin engaging the cross head of the said
piston rod substantially as shown and described.
2. In a rotary engine the combination with a revolving disc secured to the main
driving shaft and carrying two or more sets of cylinders each set consisting of two

page_text: cylinders placed diametrically opposite each other of a piston in each of the said
cylinders and a cross-head secured on each of the said piston rods and provided with
a slot extending at right angles to the said piston rod and a fixed pin held eccentric
to the centre of the said disc and extending into the said slot of the cross head
substantially as shown and described.
3. In a rotary engine the combination with a revolving disc secured to the main
driving shaft and carrying two or more sets of cylinders each set consisting of two
cylinders placed diametrically opposite each other of a piston in each of the cylinders
a piston rod connecting the two pistons of a set of cylinders and a cross head secured
on each of the piston rods and provided with a slot extending at right angles to the
said piston rod a fixed pin held eccentric to the centre of the said disc and extending
into the said slots of the cross heads and a steam chest formed on the bearing of
the said disc and connected by suitable ports with the sets of steam cylinders,
substantially as shown and described.
4. In a rotary engine the combination with a revolving disc secured to the main
driving shaft and carrying two or more sets of cylinders each set consisting of two
cylinders placed diametrically opposite each other of a piston rod connecting the two
pistons of a set of cylinders and a cross head secured on each of the said piston rods
and provided with a slot extending at right angles to the said piston rod a fixed pin
held eccentrically to the centre of the said dise and extending into the said slots of
the cross heads a steam chest formed on the bearing of the disc and provided with
two live steam ports and a slide valve held over the said two live steam ports so that
when one is opened the other is closed whereby the engine can be reversed substantially
as shown and described.
5. In a rotary steam engine the combination with a bearing provided with steam
inlet ports and exhaust ports of a steam chest formed on the said bearing a valve hold
to slide in the said bearing over the said two ports so that when one is open the
other is closed a disc held to rotate on the said bearing and secured to the main
driving shaft said disc being provided with ports adapted to register with the said
steam inlet and outlet ports in the bearing two or more sets of cylinders secured to
the said disc each set consisting of two cylinders placed diametrically opposite each
other and connected with each other by a piston rod carrying a cross-head and a fixed
pin held eccentrically to the centre of the said disc and adapted to engage the cross
heads of the said piston rods substantially as shown and described.
6. In a rotary engine the combination with a bearing provided with inlet and
outlet ports of a steam chest formed on the said bearing and into which open the
said inlet ports a valve held to slide over the said inlet ports so that when one is
open the other is closed a disc held to rotate on the said bearing and provided with
channels adapted to register with the said inlet and outlet ports slides held over
the said channels so as to connect the latter alternately with the respective inlet and
outlet ports two or more sets of cylinders held on the said disc and into which open
the said channels in the disc each set of cylinders consisting of two cylinders placed
diametrically opposite each other a piston held to slide in each of the cylinders a
piston rod connecting the two pistons of one set of cylinders a cross head formed in
the middle of each piston rod each cross head being provided with a slot extending at
right angles to the piston rod and a fixed pin held eccentrically to the centre of the
said disc and extending into the slots of the said cross-heads substantially as shown
and described.