Year: 1886

page_text: I, JOBN HARRISON DARRAGH, residing at 33, Oak Grove, San Francisco, in the
County of San Francisco, and State of California, 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 :-
Figure, 1, is a perspective viow of my improved engine as arranged for use.
Figure, 2, is a plan view of the upper side of the same.
Figures, 3, and, 4, are vertical sections upon line, x-x, of figure, 2, and show the
valve and piston in different positions.
Figure, 5, is a like view of the same upon line, 2-z, of figure, 2.
Figure, 6, is a perspective view of the valve separated from its casing, and,-
Figure, 7, is a like view of the combined cylinder and valve casing, together,
with one of its heads.
Letters of like name and kind refer to like parts in each of the figures.
The object of my invention is to increase the efficiency and to render more
certain the operation of rotary steam engines, to which end, said invention,-
Consists principally, as an improvement in rotary engines, in combining with the
annular piston chamber of a steam cylinder, a rotary valve which is journaled
within one side of said chamber and by a partial rotation is adapted to divide the
same transversely at such point, and positive automatic mechanism for turning the
valve first one way and then the other, substantially as and for the purpose herein-
after specified.
It consists further, as an improvement in rotary engines, in combining with the
annular piston chamber of a steam cylinder, a rotary valve which is journalled
within one side of said chamber and, by a partial rotation in one direction is
adapted to divide said chamber transversely at such point and by a partial
rotation in an opposite direction, to open said chamber and to form a continuation
of its outer side, and automatic positive mechanism for rocking the valve in both
directions, substantially as and for the purpose hereinafter described.
It consists further, as an improvement in rotary engines, in combining with the
annular piston chamber of a steam cylinder, a rotary valve which is adapted by
movement upon its axis to divide said chamber transversely at such point aud at
the same time to open communication between a steam supply and said chamber

page_text: at one side of said valve, and positive means for rocking the valve in both directions,
substantially as and for the purpose hereinafter set forth.
It consists further, as an improvement in rotary steam engines, in the annular
piston chamber, in combination with the piston adapted to be moved through the
same, the rotary valve adapted to close or divide the annular chamber provided
with a recess in one side adapted to form a continuation of the annular chamber
when the valve is turned in one direction and when turned in the other direction
to form a port connecting the annular chamber with the source of supply of steain
and means for rotating the valve, substantially as and for the purpose described.
It consists, further, as an improvement in rotary steam engines, in combining
with the annular piston chamber and the piston moving therein, a valve casing
having an inlet and outlet port, the rotary valve dividing the annular chamber, cut
away on one side so as to permit communication between the inlet port and the
piston chamber when the valve is turned in one direction and to form a continuation
of the chamber when the valve is. turned in the other direction, and having the
port or passage adapted to establish communication between the chamber on the
rear side of the valve and the exhaust or outlet port when the valve is turned to
divide the chamber and admit steam thereto, all substantially as hereinafter
described.
It consists, further, as an improvement in rotary engines, in a steam cylinder
provided with an annular piston chamber and a piston adapted to be moved
through the same, a rotary valve which, by a movement upon its axis may be
caused to divide said chamber transversely at such point, and to simultaneously
open communication between said chamber and an inlet steam passage, in com-
bination with a second valve which operates to control the admission of steam to
said passage, and positive automatic mechanism for operating both of said valves
in both directions, substantially as and for the purpose hereinafter described.
It consists, further, as an improvement in rotary engines in a steam cylinder
provided with an annular chamber, the piston connected with a centrally journalled
shaft and adapted to be moved through said chamber, the rotary valve which by a
movement upon its axis, is capable of dividing said chamber transversely and
opening communication between one end of the same and a steam inlet passage,
and of simultaneously opening communication between the opposite end of said
chamber and an exhaust passage, in combination with a lever operated positively
by suitable connection with the piston shaft, and a link connected with the lever
and an arm on the valve shaft, all substantially as and for the purpose hereinafter
specified. It consists, further, in combining with the annular piston chamber, the
piston travelling therein, the central shaft with which the piston is connected,
the rotary valve extending across the chamber, at one point, cut away on one side,
and provided with an exhaust passage on the other side, the valve casing having
the inlet and exhaust ports, the slide valve for opening and closing the inlet port
and an eccentric on the piston shaft, an eccentric rod, the eccentric strap thereon,
and a lever connected by suitable connecting means with the slide valve and
the shaft of the rotary valve, substantially as and for the purpose hereinafter
described.
It consists, finally, as an improvement in rotary engines, in a steam cylinder
provided with an annular chamber, the piston connected with a centrally journalled
shaft and adapted to be moved through said chamber, the rotary valve which, by
a movement upon its axis is capable of dividing said chamber transversely and
opening communication between one end of the same and a steam inlet passage,
and of simultaneously opening communication between the opposite end of said
chamber & an exhaust passage and a slide valve which operates to control the
admission of steam to said cylinder, in combination with each other, and with
automatic mechanism for operating both of said valves, substantially as and for the
purpose hereinafter set forth.
In the carrying out of my invention into practice, I preferably make a double
engine, and in such event, construct the cylinder, A, and their valve boxes or

page_text: casings, A', from one piece of metal, said cylinders having the same axis and being
joined together at their inner ends, and at their lower sides provided with suitable
supporting legs, A². The outer end of each cylinder, A, is enclosed by means of a
head, A, which is provided with an annular flange, a, that projects inward nearly
to the longitudinal center of the same and coincides with a similar flange, a¹, which
projects outward from the rear end of said cylinder.
Said flanges separate the interior of said cylinder into an exterior and an interior
annular chamber, a³, and, a³, respectively, which communicate through a narrow
radial opening which is left between the inner ends of the flanges. Passing axially
through the cylinders, A, and their heads, A3, is a shaft B, which at or near its ends
rests within and is supported by suitable journal boxes, C. Upon said shaft, within
each cylinder, is a disc, D, that closely fills the space between the inner ends of the
flanges or partitions, a, and, a', and has its outer end flush with or slightly below
the peripheries of said partitions. Said disc is connected with said shaft by means
of two collars, E, one of which is keyed or otherwise secured to the latter at each
side of the former, and is provided with a radial flange, e, that extends to the
adjacent partitions, a, or, a¹, and, in connection with the opposite flange, e, is rigidly
attached to said disc by means of bolts, e', which pass transversely through the
same. At one point upon the disc, D, its edge is extended radially outward to or
near the inner periphery of the cylinder, A, and to such extension or lug, d, is
secured a piston, F, which has a rectangular form in plan view, and closely fiils
the outer chamber, a², radially and transversely. Said piston is provided with
packing plates, f, that are arranged to break joints like the ordinary piston
packing rings, & operate to produce a steam tight joint between said piston and
the contiguous sides and ends of said chamber, a², while permitting the former to
have free circumferential movement within the latter.
It is intended that the joints between the sides of the disc, D, and the ends of
the partitions, a, and, a', shall be practically steam tight, but in order to prevent
the leakage of steam through any defects in the joints at such points, the shaft, B,
is packed within each cylinder head, A³, by means of an ordinary stuffing box
and gland.
At the upper end of each cylinder, A within the casing, A¹, is
provided a cylindrical chamber, a', which is arranged with its axis in a line with
the axis of said cylinder and has, preferably about one-fourth the diameter of the
outer chamber, a¹.
The lower portion of said chamber, a, and the upper portion of said
chamber, a², open into each other, and if the lines of the former were completed,
its lower side would just intersect the lower side of the latter at such point.
Within the chamber, a, is placed a cylindrical valve, G, which substantially fills
the same and is adapted to be partially rotated therein by means of a radial arm, g,
that is secured upon the outer end of stem, g', which projects axially from the outer
end of said valve, a connecting rod, H, that is pivoted upon and extends between
said arm and an arm, i, of a rock shaft, I, and an eccentric or cam, K, which is
placed upon the shaft, B, and is connected with said rock shaft by a rod, L, the
arrangement being such that at each revolution of said shaft, said valve will be
partially rotated in each direction. From the upper, front side of the valve
chamber, a, an inlet steam passage, a³, extends upward through a valve seat, uº,
which is formed at the upper side of the casing, a¹, while from the rear side of
said chamber, an outlet steam passage, a', extends rearward and connects with an
exhaust pipe, a, that is common to both engines. The valve, G, is provided
within one side with a recess or port, g2, which, when said valve is turned to the
limit of its motion in one direction coincides with and restores the outer line of
the chamber, a², at such point, but when said valve is turned to the opposite limit
of its motion, opens communication between the inlet port, as, and the interior of
said chamber. A second port, 93, having substantially a V-shape in end elevation
is provided with the rear side of said valve and operates to connect the rear side of
said chamber, a², with the exhaust port, a7, when said valve is turned to permit
steam to enter the front side of said chamber-

page_text: The valve seat, a, is enclosed by means of an ordinary steam-chest, M, and
within the same, for each engine, is placed a slide valve, N, of usual form which,
by means of a valve rod, O, that is connected with the same and with the rock
shaft, I, operates to open and close the port, a³, so as to admit steam to the
cylinder at the proper time. A pipe, P, connecting the steam chest, M, with a
steam supply, completes the engine, which operates as follows; viz.-The valve
actuating mechanism is so adjusted as to cause the rotary valve, G, to occupy the
position shown in figure, 3, when the piston, F, is passing through the upper part
of the cylinder, so as, thereby, to afford free passage for said piston beneath said
valve. While said valve is in such position, the slide valve, N, is in position to
close the steam port, a³, & cut off communication between the steam supply & the
cylinder.
Immediately after the piston has passed the rotary valve, the latter is turned
to the position seen in figure, 4, and the slide valve is simultaneously moved from
over the inlet port, by which means steam is freely admitted to the cylinder in
rear of said piston and in front of said rotary valve where, by pressure, and
expansion, it operates to move said piston forward within its annular chamber.
At the instant when the rotary valve moves to position to permit steam to
enter the cylinder, it also opens communication between the said cylinder, in front
of the piston, & the exhaust port, and, thereby, the steam within such space is
permitted to freely escape.
If desired, the valve connection with the exhaust, may be dispensed with and an
open passage left between the cylinder & exhaust through which steam may freely
escape. It will be readily seen that by use of ordinary reversing mechanism, the
motion of the engines can be reversed.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is,
1. As an improvement in rotary engines, in combination with the annular piston
chamber of a steam cylinder, a rotary valve which is journalled within one side
of said chamber and, by a partial rotation, is adapted to divide the same trans-
versely at such point, and positive automatic mechanism for turning the valve first
one way and then the other; substantially as and for the purpose specified.
2. As an improvement in rotary engines, in combination with the annular piston
chamber of a steam cylinder, a rotary valve which is journalled within one side of
said chamber and, by a partial rotation in one direction, is adapted to divide said
chamber transversely at such point and, by a partial rotation in an opposite
direction to open said chamber and to form a continuation of its outer side, and
automatic positive mechanism for rocking the valve in both directions, substan-
tially as and for the purpose described.
3. As an improvement in rotary engines, in combination with the annular
piston chamber of a steam cylinder, a rotary valve which is adapted by movement
upon its axis to divide said chamber transversely at such point & at the saine
time, to open communication between a steam supply & said chamber at one side
of said valve, & positive means for rocking the valve in both directions, substan-
tially as & for the purpose set forth.
4. As an improvement in rotary steam engines, the annular piston chamber, in
combination with the piston adapted to be moved through the same, the rotary
valve adapted to close or divide the annular chamber, provided with a recess in
one side adapted to form a continuation of the side of the annular chamber when
the valve is turned in one direction, & when turned in the other direction to form
a port connecting the annular chamber with a source of supply of steam, and
means for rotating the valve, substantially as and for the purpose described.
5. As an improvement in rotary steam engines, in combination with the annular
piston chamber and the piston moving therein, a valve casing having an inlet and
outlet port, the rotary valve dividing the annular chamber, cut away on one side so

page_text: as to permit communication between the inlet port and the piston chamber when the
valve is turned in one direction, and to form a continuation of the chamber when
the valve is turned in the other; direction, and having the port or passage adapted
to establish communication between the chamber on the rear side of the valve and
the exhaust or outlet port when the valve is turned to divide the chamber and
admit steam thereto, all substantially as described.
6. As an improvement in rotary engines, a steam cylinder provided with an
annular piston chamber and a piston adapted to be moved through the same, a
rotary valve which by a movement upon its axis may be caused to divide said
chamber transversely at such point and to simultaneously open communication
between said chamber and an inlet steam passage, in combination with a second
valve which operates to control the admission of steam to said passage and positive
automatic mechanism for operating both of said valves in both directions, sub-
stantially as and for the purpose described.
7. As an improvement in rotary engines, the steam cylinder provided with an
annular chamber, the piston connected with a centrally journalled shaft and
adapted to be moved through said chamber, the rotary valve which by a move-
ment upon its axis is capable of dividing said chamber transversely and opening
communication between one end of the same and a steam inlet passage, & of
simultaneously opening communication between the opposite end of said chamber
and an exhaust passage, in combination with a lever operated positively by suitable
connection with the piston shaft, and a link connected with the lever and an arm
on the valve shaft, all substantially as and for the purpose specified.
8. In combination with the annular piston chamber, the piston travelling therein,
the central shaft with which the piston is connected, the rotary valve extending
across the chamber, at one point cut away on one side, and provided with an
exhaust passage on the other, the valve casing having the inlet and exhaust ports,
the slide valve for opening and closing the inlet port, an eccentric on the piston
shaft, an eccentric rod, the eccentric strap thereon, and a lever connected by
suitable connecting means with the slide valve and the shaft of the rotary valve,
substantially as & for the purpose described.
9. As an improvement in rotary engines, the steam cylinder provided with an
annular chamber, the piston connected with a centrally journalled shaft & adapted
to be moved through said chamber, the rotary valve which, by a movement upon
its axis is capable of dividing said chamber transversely and opening communi-
cation between one end of the same & a steam inlet passage, and of simultaneously
opening communication between the opposite end of said chamber and an exhaust
passage, and a slide valve which operates to control the admission of steam to said
cylinder, in combination with each other and with automatic mechanism for
operating both of said valves, substantially as and for the purpose set forth.
Doted th dow of June 1986