IMPROVEMENTS IN ROTARY STEAM ENGINES
Year: 1864

page_text: LETTERS PATENT to Hyde Bateman, of 3, Castlenau Cottages, Barnes,
in the County of Surrey, Surveyor, for the Invention of "IMPROVEMENTS
IN ROTARY STEAM ENGINES."
Sealed the 8th September 1864, and dated the 16th March 1864.
PROVISIONAL SPECIFICATION left by the said Hyde Bateman at the
Office of the Commissioners of Patents, with his Petition, on the
16th March 1864.
I, HYDE BATEMAN, of 3, Castlenau Cottages, Barnes, in the County of
Surrey, Surveyor, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN ROTARY STEAM ENGINES," to be as follows:-
. This Invention of improvements in rotary steam engines relates, first," to
the employment of a hollow piston of peculiar construction through an opening
in either side of which the steam, after exerting its elastic force, may bo
drawn off, and conducted either to a condenser or into the atmosphere.
Hollow steam stops are also provided, in the upper part of which slide valves
are fitted, and have an independent motion; it is through these slide valves
that the steam is admitted from the boiler. The steam stops with the valves
are moved up and down in their guides by an excentric or other suitable
motion properly arranged to raise the stops at the proper time to allow the
piston to pass. When the stop reaches the bottom of the cylinder, and strikes
against the same, this action opens the slide valve, and admits steam to the

page_text: interior of the cylinder. The steam, by expanding between the stop and the
piston, drives the latter forward, and at the same time closes the exit valve
on this side of the piston, and opens the exit valve on the opposite side, so as
to allow the steam on that side to escape. It will be understood, that as the
valves in the piston and in the steam stops are all double action, that is, they
will allow steam to enter or escape from either side, the engine may be driven
in either direction by operating the valves accordingly. It will also be under-
stood, that by a very simple modification of the working of the parts the steam
may be admitted through the piston, and allowed to escape-through the slide
valves of the steam stops.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Hyde Bateman in the Great Seal Patent Office on the
16th September 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HYDE
BATEMAN, of 3, Castlenau Cottages, Barnes, in the County of Surrey, Sur-
veyor, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixteenth day of March, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-seventh year of
Her reign, did, for. Herself, Her heirs and successors, give and grant untó
me, the said Hyde Bateman, Her special license that I, the said Hyde
Bateman, my executors, administrators, and assigns, or such others as I,
the said Hyde Bateman, my executors, administrators, and assigns, should
at any time agree with, and no. others, from time to time and at all times
thereafter during. the term therein expressed, should and lawfully might
make, use, exercise, and .vend within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN ROTARY STEAM ENGINES," upon the condition (amongst
others) that I, .the said Hyde Bateman, by an instrument in writing under
my hand and.. seal, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be performed;
and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said Letters
Patent...
. NOW KNOW YE, that I, the said Hyde Bateman, do hereby declare the
nature of my said Invention, and in. what manner the same is to be per

page_text: formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Drawings hereunto annexed, and to the
letters and figures marked thereon (that is to say):
This Invention of "Improvements in Rotary Steam Engines" relates, first,
to the employment of a hollow piston of peculiar construction through an
opening in either side of which the steam, after exerting its elastic force, may
be drawn off and conducted either to a condenser or into the atmosphere.
Steam stops are also provided, on the side of which valves are fitted to admit
steam to the cylinder, and these steam stops have an independent motion.
The steam stops and the valves for the admission of the steam are moved up
and down in their guides by an excentric cam or other suitable motion
properly arranged to raise the stops at the proper time to allow the piston
to pass.
In the accompanying Drawings I have shewn various views of my improved
rotary engine.
Fig. 1, Sheet I., is a plan view of one of my improved steam engines,
shewing the external working parts; Fig. 2 is a horizontal section of the
same, shewing the construction of the piston and of the slide valves, and
the mode of working the latter. Fig. 3, Sheet II., is a front elevation of
the engine, the steam chests for the slide valve and for the reversing action
being shewn in section. Fig.4 is a side elevation of the engine, the steam chests
for the reversing gear being also. shewn in section in this view. Fig. 5,
Sheet III., is a side elevation of the steam cylinder, shewing the steam chests
for the slide valves and reversing gear; Fig. 6 is a similar. view of the
opposite side of the steam cylinder, shewing. the chests or chambers for the
steam stops; Fig. 7 is an elevation of the piston and its boss, shewing
the latter in plan and the exhaust ports formed therein; Fig: 8 is a similar
view of the piston and its boss, but shewing the opposite side of the boss;
Fig. 9 is a plan view of the piston, the boss of the same being seen in edge
view, and shewing the entrance to one of the exhaust passages and the slide
belonging thereto; Fig. 10 is a vertical section of the. piston and its boss
taken in the line 1, 2, of Fig. 9, the boss being seen in sectional plan so. 'as
to shew the slide valves which open and close the exhaust. passages; Fig. 11
is a horizontal section of the boss of the piston taken in the line 3, 4, of.
Figures 7, 8, and 10. Fig. 12, Sheet IV., is an interior elevation of one;
side of the cylinder, shewing the position of steam stops and of the exhaust
passages made in the boss of the cylinder and round the central shaft, axle, or
piston rod of the engine; Fig. 13 is a similar view of the other side of the
cylinder, also shewing the position of the steam stops and the steam ports.

page_text: The steam cylinder is constructed in two halves or portions, each of which
is shewn at Figures 12 and 13, Sheet IV. In these two halves of the cylinder
are formed half of the semicircular bore or space, in which the piston shewn
detached at Figures 7, 8, 9, and 10 rotates.
It will be seen, on referring to Figures 12 and 13, that the circular bore of
the cylinder is divided by the steam stops a, a, into two compartments.
These steam stops work in slots formed in the cylinder, and in order to allow
the piston to pass, are capable of being withdrawn at proper intervals into the
boxes b, b, fixed on the side of the cylinder, as seen at Fig. 6, Sheet III.
Each of the halves of the steam cylinder are constructed with a hollow boss,
in one of which bosses are formed passages c, c, for the exhaust steam, as
seen in Fig. 2, Sheet I., and Fig. 13, Sheet IV.
In the boss of the other side of the cylinder, shewn at Fig. 12, Sheet IV.
is formed a circular space d, Figures 2 and 12, to receive a portion of the
reversing gear. In the bosses of both parts of the piston are also formed
circular grooves
e, to receive metallic rings, as shewn in section at Fig. 2,
for the purpose of rendering the boss of the piston steam tight. The piston f
Fig. 2, and shewn detached at Figures 7, 8, 9, and 10, is circular in plan, and
is cast in one piece with the circular boss g, through which passes the central
shaft, axle, or rod h of the engine. The piston f is made steam-tight by
means of the metallic packing i, i, Fig. 2, which is kept pressed out by means
of the helical springs and tightening screws j, j. The circular boss 9, 9, is
placed at right angles to the face of the piston f, and contains spaces for the
exhaust passages k, k, and the valves 1, 1, for opening and closing the same.
Steam is supplied from the boiler to the chest m of the slide valve n, and
from thence passes through the chest o of the reversing gear into the cylinder.
The direction in which the piston is to be driven will be determined by the
valve P of the reversing gear, by moving which in the desired direction by
means of the hand lever s, steam may be admitted to either side of the steam
stop a, as may be required.
It will be seen, on referring to the Figures, that there are two sets of
valves and reversing gear, one for each steam stop, so that the engine may be
worked in either direction. The valves n, n, for admitting the steam into the
cylinder are actuated by the levers q, q, provided at their outer ends with
bowls q, q', which work in the excentric grooves of the cam r on the central
shaft or axle h.
The excentric groove of the cam r is shewn developed at Fig. 14, Sheet II.
In this improved engine there are duplicate exhaust passages, which being in
the boss' which travels round with the piston, the exhaust port in use (being

page_text: that. on the side opposed to the steam port) is always open, and when it
is required to reverse the engine it will only be necessary to close this
port and the corresponding steam port, and open the duplicate passages
on the other side of the steam stops. These operations are effected simul-
taneously by means of the hand levers, Figures 1 and 4, which is connected,
as shewn in Fig. 4, to the several valves. In order to alter the cut off of the
steam, the fulcra or axes of motion of the levers q, q, are made adjustable, to
which end the centre pins 1, 1, of these levers may be moved along the slots
made in the levers, as shewn at Figures 1 and 2.
In order to allow the piston to pass the steam stops a, a, the latter must
be drawn out of the way; this is effected by means of an arrangement of levers
worked by a cam t mounted on the central shaft, axle, or rod h, and provided
with an excentric groove which is shewn developed at Fig. 15.
It will be seen, on reference to Figures 1 and 2, that bowls at the end of
the short levers u, u', work in the excentric groove of the cam t, and by
means of links actuate the long levers v, v¹, to the longer arms of which are
connected by rods w, w¹, the cross heads x, x³, which support the stems of the
steam stops a, a. It will be evident that by this arrangement of levers which
are actuated by the cam t the steam stops may be drawn back at the precise
moment of time required. In order to equalize the pressure on both sides of
the stops preparatory to their being raised, the exhaust ports k, k, in the boss
of the piston are so constructed and arranged (as seen best in Fig. 10) that
when the piston has passed one steam stop, and the latter has been closed
behind it (so that steam may be admitted between this stop and the piston for
the purpose of propelling the latter forward), a small portion of the opposite
exhaust port will be carried by the motion of the piston past the other steam
stop, and consequently the expanded steam that has been enclosed or shut up
between the two steam stops will be allowed to escape behind the second
steam stop, and thus take off the back pressure previous to the stop being
withdrawn. By this means a considerable amount of friction is avoided, and
an economy of steam is effected.
I would remark, that the boss 9 of the piston is keyed securely on to the
main shuft h, and if the engine were intended to be applied for locomotive or
marine purposes, the running wheels of the locomotive engine in the one
place and the paddle wheels of the steam vessel in the other would be keyed
on to the ends of the shaft h. The motion of the piston may be arrested or
its direction changed by simply raising or depressing the hand levers, which,
as will be seen on reference to Figures 2 and 4, is connected by links to the
reversing valves, and by other links y, y', and levers to the stems =,=, which

page_text: are connected by the grooved ring z¹, Fig. 2, to the stem of the valves of the
exhaust.ports.
In witness whereof, I, the said Hyde Bateman, have hereunto set my
hand and seal, the Sixteenth day of September, in the year of our
Lord One thousand eight hundred and sixty-four.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
HYDE BATEMAN. (L.S.)