Year: 1888

page_text: I GEORGE HENRY WESTON of Boston in the State of Massachusetts, one of the
United States of America, Machinist, 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:
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This invention relates to steam engines of that class known as rotary engines,
it having for its object to provide a rotary steam engine capable of running at a
substantially high speed, my improved engine among other things being particularly
adapted for driving centrifugal machines.
My invention consists essentially of novel features of construction as will be
hereinafter described and specifically pointed out in the claim at the end of this
specification.
Figure 1 is a central transverse section of my improved engine on line y, y, Fig. 2,
the shafts a, a, being partially in section.
Figure 2, a section of Fig. 1 on line x-x.
Figure 3 a detail to be referred to, and
Figure 4, a modification to be referred to.
The shell or case A constituting the main frame work of my improved engine has
bolted or otherwise secured to it a plate a forming a removable cover for the said
case.
The case A has preferably cast integral with it two huhs a¹, a², extended into and
out side of the said case.
The hub a¹ has extended through it from inside of the case, a shaft a³ of an
abutment or cylinder a preferably made as shown to ensure lightness and speed,
and the hub a forms bearings for the shaft or rod a of a valve as herein shown
as hollow and open at one end and having its open end as herein shown fitted
into a groove in the cap a, see Fig. 1, the said groove being rendered steam tight
as shown by the packing ring a.
The abutment or cylinder a is provided with a reentrant portion b, see Fig. 2, to
form a recess or chamber into which a piston arm 6' on the hollow piston valve is
adapted to enter as will be described. The piston valve a is provided with an outlet
port 6 preferably extended the length of the said piston valve.
Figure 4, a modification to be referred to.
The shell or case A. constituting the main frame work of my improved engine has
bolted or otherwise secured to it a plate a forming a removable cover for the said
case.
The case A has preferably cast integral with it two huhs a¹, a², extended into and
out side of the said case.
The hub a¹ has extended through it from inside of the case, a shaft a³ of an
abutment or cylinder a preferably made as shown to ensure lightness and speed,
and the hub a forms bearings for the shaft or rod a of a valve as herein shown
as hollow and open at one end and having its open end as herein shown fitted
into a groove in the cap a, see Fig. 1, the said groove being rendered steam tight
as shown by the packing ring a.
The abutment or cylinder a is provided with a reentrant portion b, see Fig. 2, to
form a recess or chamber b' into which a piston arm 6 on the hollow piston valve is
adapted to enter as will be described. The piston valve a is provided with an outlet
port 6 preferably extended the length of the said piston valve.

page_text: The piston valve a has extended into its open end a segmental arm 6 herein
shown as part of the cap a, the said arm in the operation of the engine forming part
of the cut off mechanism, which is herein shown as an arm or extension 66 of a
sleeve supported by a hub 6' on the plate or cap a, the said sleeve being open at its
ends and provided with a cross head or bar at its outer ond from which is extended a
shaft or arbor c', the said shaft being extended through and supported as shown by
a. dome-shaped cap e, herein shown, as screwed upon the hub 67. The dome e of
the dome shaped cap referred to is provided with a steam inlet e shown by dotted
lines Fig. 1.
The shaft c outside the dome is provided with a crank by which the position
of the cut-off may be changed to obtain greater or less steam expansion as desired.
The shaft as has mounted upon it, as shown in Fig. 1 a gear din nesh with a
gear d' on the shaft a³, the gear & having as shown a hub to which is attached or
cast integral therewith, as shown, a balance wheel d.
In the operation of my improved rotary engine, steam is admitted into the piston
valve through the inlet c', and passes out therefrom through the port 63. As shown
in Fig. 2 the port 63 is partly uncovered and the steam issues therefrom into the
triangular shaped pocket or space B, formed by the valve a cylinder or abutment a*
and piston arın b², the said steam being prevented from escaping beyond the piston
arm b² by the spring m, as shown, but it may be by any suitable packing.
The steam admitted into the pocket B acts upon the arm 62 and rotates the
piston valve in direction of arrow 20, the said valve through the gears d, d
imparting rotation to the cylinder or abutment in the opposite direction as indicated
by arrow 21.
As the piston valve and cylinder are thus rotated, the pocket B continues to increase
in size, it retaining substantially its triangular shape, until the arm and spring m
on the abutment reach the point 25 of the case or frame, and thereafter the said case
forms part of the said steam pocket or space, the said spring bearing against the
arm as shown and constituting a packing by which the steam is prevented from
escaping from the pocket B.
Live steam continues to issue from the valve through the port 6 into the steam
pocket or space referred to, until the said port in the rotation of the valve passes
and is closed by the cut-off c, after which the steam by its expansive force completes
the rotation of the piston valve. The expanded steam is permitted to escape into
the exhaust passage d' made in the case or frame and communicating with the exhaust
pipe d as the arm 63 passes by or uncovers said exhaust passage.
Instead of the gears d, d¹, I may employ sprocket wheels e, el, and rotate them in
opposite directions by a sprocket chain or belt e passed about the wheel e¹ and an
auxiliary wheel e³, the said chain or belt passing under and being kept in contact with
the wheel e as shown by the spring actuated lever e.
To prevent steam from escaping through the bearings of the shafts a³, a³, packing
rings, are provided for the abutment or cylinder and piston valve respectively as
clearly shown in Figure 1.
Furthermore the case or frame A is provided with steam vents f³,f³, around
the hubs a, a, to permit steam which may have escaped by the packing rings
referred to, to escape from the engine without passing through the bearings, thus
allowing the said bearings to be kept well lubricated with oil fed to the bearings
through the ducts ƒ^ƒ³.
It will be noticed that when the valve is about to open or is but partially opened
the amount of clearance, which is the chamber B, is very small or substantially
nothing, thus economizing steam.
If it is desired to cut off the admission of steam to the piston at a quarter or
other desired portion of the rotation of the valve, the cut-off sleeve be will be moved
by the crank from its full to the dotted line position shown in Fig. 2.
It will be noticed that the steam inlet port is located so as to be partially opened
when the spring m or it may be the point 3 of the abutment is brought in contact
with the arm or piston.

page_text: Having now particularly described and ascertained the nature of my said Inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1. In a rotary engine, the combination with an abutment or cylinder having a
reentrant portion b, of a piston valve having an arm to enter the said reentrant
portion of the said cylinder, and a steam inlet port located so as to be partially
opened when the point of the said reentrant portion b is brought substantially in
contact with the piston, and a cut-off mechanisin, as and for the purpose specified.
2. In a rotary engine, the combination with an abutment or cylinder having a
reentrant portion b, of a hollow piston valve a having a piston 6', and provided with
a port 6, and an adjustable cut-off mechanism within the said piston valve, substantially
as described.
3. In a rotary engine, the combination with an abutment or cylinder having a
reentrant portion b, of a hollow valve as having a piston 6, and provided with a port b³,
and a segmental arm b* provided with the extension 6, the said arm and extension
being entered into said hollow valve, substantially as described.
4. The case or frame A having the bearings a¹, a extend into and outside of the
said case or framo, combined with the cylinder a', and hollow valve a", having shafts
extended into and supported by said bearings, substantially as described.
5. In a rotary engine, the combination with an abutment or cylinder having a
reentrant portion 6, of a piston valve having an arm to enter the said reentrant portion
of the said cylinder to effect the minimum clearance, and an adjustable cut-off
mechanism within said piston valve, substantially as described.
Dated the 12th day of November 1888.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London,
Agents for the Applicant.