Improvements in Rotary Prime Movers.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Rotary Prime Movers.
I, WILLIAM DEWAR, Senior, of 166, Perth Road, Dundee, in the County of
Forfar, Scotland, Engineer, do hereby declare the nature of this invention to be
as follows:-
:―
This invention relates to improvements in rotary prime movers, the object
being to utilize the elastic force of such a fluid as steam in a new and improved
manner.
In carrying out my invention I mount upon a shaft a wheel to which is
attached two or more pistons so shaped that they accurately fit an annular pas-
sage of circular section in the casing. This annular passage is closed except
at points where the steam is admitted or exhausted. It is also open right round
where the wheel or disc which carries the pistons passes through. Provision
is made for making the casing where the piston wheel passes through, steam
tight, preferably by means of rings pressed against the sides of the wheel and
the inner surface of the casing, by means of springs. A certain number of
divisional closing valves whose faces are parts of circles are placed, preferably
at equal intervals, around the annular passage. For example, if two pistons
are used three or more of such valves will be required. These valves are operated
by a duplex cam wheel mounted on the piston wheel shaft, the mechanism for
operating them consisting of a duplex cam mounted on an arbor so arranged
that the outer wheel cam when it comes in contact with the outer face of such
duplex cam partly rotates the arbor and when the inner cam comes in contact
with its inner face pushes it back again and so turns the arbor backwards and
forwards. These cams on the wheel are not continuous but are cut away to per-
mit of such movements. On the arbor is mounted a segment of an internal
wheel which gears with a pinion keyed on the arbor and on which is mounted
the divisional valve. Conical valves are used for controlling the admission and
emission of the steam, such valves being controlled by means of a cam wheel
mounted on the main shaft, such wheel having elevations and depressions or
sinuous grooves so designed that the valves by means of cam rollers and levers
are opened and shut at suitable intervals. Preferably arrangements are made
whereby the cam wheel can be automatically or otherwise altered, so that the
points of cut off and exhaust may be altered also.
נית
ALL
Antahan 1007
GEO. C. DOUGLAS & Co.,
41, Reform Street, Dundee,
Agents for Applicant.

page_text: Improvements in Rotary Prime Movers.
I, WILLIAM DEWAR, Senior, of 166, Perth Road, Dundee, in the County of
Forfar, Scotland, Engineer, 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;-
1
This invention relates to improvements in rotary prime movers, the object
being to utilize the elastic force of such a fluid as steam in a new and improved
manner.
And in order that my said invention and the manner of performing or carry-
ing the same into effect or practice may be properly understood, I have hereunto
appended two explanatory sheets of drawings in which the same reference
numerals are used to indicate corresponding parts in all the figures where
shown.
Figure 1, is a section at B, B, (Figure 2) of a rotary prime mover looking
in the direction of the arrow Y.
Figure 2, is a section at A, A, (Figure 1) looking in the direction of the
arrow Z.
Figure 3, is a half section at C, C, (Figure 1) looking in the direction of the
arrow Z
Figure 4, is a half section at D, D, (Figure 1) looking in the direction of the
arrow X.
Figure 5, is a section at E, E, (Figure 6) of another modification of the inlet
valves.
Figure 6, is a face view of same looking in the direction of the arrow W,
(Figure 5).
In carrying out my invention I mount upon a shaft 10, a wheel 11, to which
is attached two or more pistons 12, so shaped that they accurately fit an annular
passage 13, of circular section, in the casing. This annular passage is closed
except at points 14, where the steam is admitted or at points 15, where it is
exhausted. It is also open right round at 16, where the wheel or dise which
carries the pistons 12, passes through. Provision is made for making the casing
where the piston wheel 11, passes through, steam tight, preferably by means
of rings 17, pressed against the sides of the wheel and the inner surface of the
casing by means of springs, or because of their own elasticity. A certain num-
ber of divisional closing, valves, 18, whose faces are parts of circles, are placed,
preferably at equal intervals around the annular passage. For example if two
pistons are used three or more of such valves will be required, and in the motor
as illustrated and partly described which has three pistons, at least four valves
are necessary. These valves are operated by a duplex cam wheel 19, mounted
on the piston wheel shaft 10, the mechanism for operating them consisting of
a duplex cam 20, mounted on an arbor 21, so arranged that the outer cam 22,
when it comes in contact with the outer face 23, of such duplex cam, partly
rotates it and when the inner cam 24, comes in contact with its inner face 25,
pushes it back again and so turns the internal sector wheel 26, backwards and
forwards and with it the arbor 28, and the divisional valve 18. These cams 22,
and 24, on the wheel are not continuous, but are cut away to permit of such
movements. On the arbor 21, is mounted a segment of an internal sector
wheel 26, which gears with a pinion 27, keyed on the arbor 28, and on which is
mounted the divisional valve 1S. 40 are blocks fitted into the casing, their pur-
pose being to provide a continuous bearing for the external faces of the pistons

page_text: 12. Conical valves 29 are used for controlling the admission of the steam,
such valves being actuated by means of a cam wheel 30, mounted on the main shaft
10; such wheel having elevations and depressions so designed that the valves by
means of cam rollers 31, are opened and shut at suitable intervals.
Instead of using conical valves to control the admission of the steam I may
use a ring slide valve; such a modification being illustrated by Figures 5 and 6.
In this modification a wheel 32, which is mounted on the main shaft 10, carries
round with it as it revolves the ring slide valve 33, such valve having three
ports 39, such ports being so arranged relative to the admission ports 14, that
they are opened or closed at suitable intervals, as previously described with
reference to the conical valves.
The motor is actuated as follows;-Steam from the generator passes into the
steam chest 34, through the passage 41, and from thence to the annular pas-
sage 13, when the valves 29, or ports 39, permit. The piston 35, (Figure 4)
is in the correct position for its admission valve to be opened while the piston
36, is at the point where its admission valve closes. As each piston comes up
close to the divisional valve in front of it, such valve opens and is in the position
shown by the valve 37, (Figure 2) thus permitting the piston to pass. These
divisional valves are operated at the suitable periods by means of the duplex
cams 20, 22, 24, and their appurtenances, as previously described. The steam
is permitted to exhaust through the ports 15, the divisional valve in front of a
particular piston being at that time open while the other divisional valve im-
mediately behind it is closed. In this manner the wheel 11 is made to continuously
rotate in the direction of the arrow V. The pistons are made steam tight by means
of the pieces 38 such pieces being pressed against the sides of the annular passage
by means of springs as shewn.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
claim is:
(1). In rotary prime motors, the mode of causing a main shaft to rotate, sub-
stantially as hereinbefore described and illustrated by Figures 1, 2, 3, and 4,
the combination consisting of a wheel and pistons moving in an annular space
or chamber, conical admission valves actuated by a cam wheel on the main
shaft; divisional valves actuated by duplex and wheel cams and exhaust ports
uncovered by the passing pistons.
(2). In rotary prime motors, the combination of conical valves with a cam
wheel on a main shaft, substantially as described.
(3). In rotary prime motors, the combination of a ring slide valve with a
main shaft and driving wheel, substantially as described and illustrated by
Figures 5 and 6.
(4). In rotary prime motors, the combination of divisional valves with duplex
cams actuated by a duplex wheel cam, substantially as described.
(5). In rotary prime motors the combination of a wheel and pistons with an
annular casing, as described.
(6). In rotary prime motors the combination of a duplex cam with an in-
ternal sector,. pinion wheel and divisional valve, as described.
Dated this 6th day of June. 1898.
GEO. C. DOUGLAS & Co.,
41, Reform Street, Dundee,
Agents for Applicant.