IMPROVEMENTS IN ROTARY ENGINES
Year: 1885

page_text: THOMAS WHITAKER Summerfield Woodside Horsforth Nr Leeds do hereby
declare the nature of my invention for IMPROVEMENTS IN ROTARY ENGINES to be
as follows:-
This invention relates to the construction of Rotary Engines; and the object
I have mostly in view is to provide an Engine that will utilize the exhaust steam
to carry the Engine over the dead ends, for this purpose I provide two Cylinders
of different diameters, the smaller one for the high pressure, & the larger one for
low pressure, the driving shaft or piston passes through both Cylinders touching
the circumferencial surface of the Cylinders at either the top or bottom sides
sufficiently tight as not to allow the steam to pass between the driving shaft
& the Cylinders.
The driving shaft has two orifices cut through it one in each Cylinder the whole
length of the inside of each Cylinder, but at different angles to each other; through
these orifices blades or wings work which are a little shorter both in length
& diameter than the Cylinders; to make the blades the full length & diameter of
the Cylinders caps of brass or any other more suitable metal are fitted on to the
blades, with springs behind them between the blades & the caps, so as to make
them steam tight, at whatever angle they may be at, as the blades have to vary in
diameter, with revolving with the driving shaft which is not in the center of the
Cylinders. The driving shaft inside the Cylinders requires to be a little over the
half the diameter of the Cylinders, so as to keep the brass caps in their positions.
Both Cylinders have two steam feed ports & two exhaust ports. The feed porta
are one on each side of the driving shaft in both Cylinders. The High pressure
cylinder exhausts at about two thirds of a revolution & the Low pressure exausts
at about one third of a revolution from the feed ports.
The mode of working the above Engine is as follows, by opening the feed port
on that side of the driving shaft that the engine is required to revolve the engine
is set in motion, & when the blade has travelled as far as the exhaust port, the
steam passes into the low pressure cylinder & this pressure is brought to bear on
the blades, in both the high & low pressure cylinders, forcing them both in the
same direction, & therefore doing away with back pressure at that end of the
blade, and when the opposite end of the blade in the high pressure Cylinder begins
to receive back pressure the steam is admitted behind this end of the blade and

page_text: forces it forward & more than balances the back pressure, And it is thus seen
that there is no dead end in this engine, as there is about equal pressure on the
blades, the whole of the revolution & thus obviates the necessity of a fly wheel
to make this engine run steadily. And when this engine is required to be
reversed, the steam port is opened on the opposite side of the driving shaft & then
the engine will turn round in the opposite direction with just the same results as
above described.
This engine can also be worked with one cylinder by carrying the exhaust ports
about of a revolution from the feed port, but it will not work as economically
& steadely as when worked compound.
I, THOMAS WHITAKER, Horsforth, near Leeds, 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 :-
•
This invention. relates to the construction of rotary engines, and the object I have
mostly in view is to provide an engine that will utilize the exhaust steam to carry
the engine over the dead points or ends; for this purpose I provide two cylinders
of different cubical contents, the smaller one for the high pressure, and the larger
one for the low pressure.
The invention is best described by aid of the accompanying drawings in which
- Figures 1 to 4 show the engine in detail, Figure 1 longitudinal section, Figure 2
transverse section through high pressure cylinder on line - Figure 1; Figure 3
transverse section through low pressure cylinder on line y-y Figure 1; and
Figure 4 plan.
Figures 5 to 8 give a general view of engine with valves and connections ;
Figures 5 and 7 being end elevations; Figure 6, side elevation, and Figure 8, plan.
In these A is the piston shaft passing through the high pressure cylinder B and
the low pressure cylinder C. The shaft is enlarged in diameter inside the cylinders
which latter are formed to face each other with open flanged ends abutting
against a diaphragm D. between them. The enlarged sbaft touches the entire
length of each of the cylinders at one point in the circumference (the bottom in
both cylinders in the example shown in the drawings) thus preventing at this
point the steam passing between the driving shaft and cylinder surface.

page_text: The driving shaft has an orifice cut through it, one in each cylinder, for the sliding
pistons E, F, respectively, the whole length of the inside of each cylinder, but at
different angles to each other, through these orifices, blades, or pistons work. These
pistons are formed of an interior body G, two caps or end pieces H, H, pressed
apart by springs I, I, set in the body, and side pieces K K held against the cylinder
end by springs J, J, so as to make the pistons steam tight. at whatever angle they
may be at, as the centre of the shaft not being in the axis of the cylinder the
length of the pistons has to vary in diameter while revolving with the driving
shaft. The driving shaft inside the cylinders requires to be a little greater in
diameter than half the diameter of the cylinders so as to keep the brass caps or end
pieces H in their positions. Each cylinder has two steam ports, N in the high
pressure cylinder, and N¹ in the low pressure cylinder, and exhaust ports O in the
high pressure cylinder and 0¹ in the low pressure cylinder. The steam ports are
placed one on each side of the driving shaft. The high pressure cylinder exhausts
at about two thirds of a revolution, and the low pressure exhausts at about one
third of a revolution from the steam ports. As hereinbefore stated the orifices in
the driving shaft in which the pistons E and F slide are placed at an angle one to
the other so that the piston in the high pressure cylinder stands at an angle to or
in a different plane to that in the low pressure cylinder. The dotted lines in
Figure 2 show the position of the piston F in relation to the piston E when the
latter is in the position shown. The lines n-n are the centre lines of the steam
ports N of the low pressure cylinder, and the lines o-o the centre of the exhaust
ports O¹ of the low pressure cylinder. The pistons are not shewn in exactly the
same position in Figure 1 as in Figures 2 and 3, in the former the piston E of
high pressure cylinder is shewn vertical and the piston F of low pressure cylinder
is shewn horizontal in order more clearly to shew the details of construction.
the bottom of the cylinder or at that point where most wear occurs a separate
piece L is placed as a liner and is maintained in position against the shaft and
adjusted as wear takes place by set screws M, M. If one or both of the cylinders
touch the shaft at the top or other point instead of the bottom, the separate adjust-
able piece L is placed at the point of contact. P is a three way cock for admitting
steam to the ports at either side of the high pressure cylinder, R a four way cock
for admitting steam from the exhaust ports at either side of the high pressure
cylinder to the steam ports at the opposite side of the low pressure cylinder, and
P¹ a three way cock for the exhaust steam from the ports at either side of the low
pressure cylinder. When the engine is working in one direction the cocks are so
turned that the steam will take the course shown by the arrows in full, the other
passages being closed. When the engine is to be reversed the cocks are so turned
as to cause steam to travel as shown by the dotted arrows. S are packing rings in
the diaphragm between the cylinders to keep all tight. T and T¹ rubber packinga
to take the strain off the piston or form a steam tight joint. In practice so far
I have found these of little or no use, but they may perhaps be required with some
engines. U are drain cocks.
At
The mode of working the above engine is as follows. By opening the feed ports
on that side of the driving shaft that the engine is required to revolve (by means
of the cocks P and R, and opening the exhaust port on the opposite side of the
piston by means of the cock P₁₁) the engine is set in motion, and when the high
pressure piston has travelled as far as the exhaust port the steam passes into the
low pressure cylinder, and this pressure is brought to bear on the pistons in both
the high and low pressure cylinders, forcing them both in the same direction, and
therefore doing away with back pressure at that end of the high pressure piston,
and when the opposite end of the piston in the high pressure cylinder begins to
receive back pressure, the steam is admitted behind this end of the piston and
forces it forward and more than balances the back pressure, and it is thus seen that
there is no dead point or end in this engine as there is about equal pressure on the
pistons, the whole of the revolution. Thus the necessity of a fly wheel to make
this engine run steadily is obviated or very greatly reduced.
When this engine is

page_text: required to be reversed, the steam port is opened on the opposite side of the driving
shaft by turning the cocks P and R, and the opposite exhaust port opened by
turning the cock P¹ then the engine will rotate in the opposite direction with just
the same results as above described. This engine can also be worked with one
cylinder by placing the exhaust ports about of a revolution from the feed port,
but it will not work as economically and steadily as when worked compound.
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 :-
1st. A compound rotary engine having the piston of the high pressure cylinder 1
placed at a different angle from that of the low pressure cylinder relatively to their
respective contact points between cylinder and shaft, whereby an engine without
dead points is secured, substantially as described.
2nd. A compound rotary engine in which the high and low pressure cylinders.
have the same shaft, but are separated by a diaphragm, and in which the pistons 1
and cylinders are so arranged that each shall be in full action when the other is at
its dead point.
3rd. The pistons for rotary engines, substantially as herein described.