IиPROVE- MENTS IN ROTARY ENGINES FOR OBTAINING MOTIVE POWER AND FOR RAISING AND FORCING FLUIDS
Year: 1874

page_text: LETTERS PATENT to William Eli Sudlow, of Oldham, in the County
of Lancaster, Mechanical Engineer, for the Invention of "IиPROVE-
MENTS IN ROTARY ENGINES FOR OBTAINING MOTIVE POWER AND FOR RAISING
AND FORCING FLUIDS."
Sealed the 26th February 1875, and dated the 29th August 1874.
PROVISIONAL SPECIFICATION left by the said William Eli Sudlow
at the Office of the Commissioners of Patents, with his Petition, on
the 29th August 1874.
I, WILLIAM ELI SUDLOW, of Oldham, in the County of Lancaster,
Mechanical Engineer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN ROTARY ENGINES FOR OBTAINING MOTIVE POWER AND FOR
RAISING AND FORCING FLUIDS," to be as follows :—
These improvements relate to an Invention for which Letters Patent,
No. 272, were granted to me on the 23rd day of January 1873, and
have for their object the simplification of the rotary engine described
in the Specification of the said Letters Patent. In its improved form

page_text: I construct the cylinders forming the annular chambers of my rotary
engine without the steam jacket surrounding them, as heretofore; but
I retain the method described of mounting the piston or drum upon
the main driving shaft in order to allow for expansion, except in some
cases where I find it more convenient to mount the drum direct upon
the shaft and not upon an intermediate boss. The disc plates or flanges
secured to the ends of the drum are provided with a spring or piston
ring inserted in a suitable annular groove, and thus a more perfect and
steam-tight joint is produced. The reciprocating slide or shutter is also
differently constructed and actuated.
Instead of employing the piston with larger area on one side than
the other to actuate such slide, I form a passage on the under side
communicating with the interior of the cylinder, and thus I permit the
same pressure to be always exercised on the back of the slide as obtains
in the interior of the cylinder. A rod projects from the back of this
slide into a steam chamber in which the pressure is constant, this steam
chamber being fitted with a suitable equilibrium or slide valve which
by means of an eccentric or cam controlls the admission of steam into
the cylinder. The area of the rod is sufficient to ensure the slide being
kept in contact with the drum and the nose of the slide, and the piston
upon the drum are so formed that when the drum revolves the piston
coming in contact with it gradually pushes the slide out of the way.
to permit it to pass, when the pressure upon the back of the rod instantly
causes the slide to follow the incline on the back of the piston, and thus
to close itself against the revolving drum. And in order to ensure the
slide being steam-tight at either end I insert a brass packing in a
suitable channel formed in the slide, and which packing is forced
downwards by the steam pressure against the face of the discs or flanges
of the drum; and I further cover the ends of the recess in which the
slide reciprocates with the special covers which are again enclosed by
the ends or covers of the cylinder.
This improved form of engine may also be made reversible with a
single slide by having steam passages formed through the slide, either
of which may be closed at pleasure by a suitable valve, according to
the direction in which it is required to run the engine, there being
two exhaust ports, either of which may be closed when the other is
open.

page_text: The improved construction of rotary engine herein-before described
may be driven by water or compressed air instead of steam, and is also
applicable to the purpose of raising and forcing various fluids, forming
an efficient rotary pump or blower, in which case it may either be
driven from a line shaft in a convenient position, or direct by combining
it with one or more of my improved motive-power drums upon the same
shaft, thus forming a very compact arrangement.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Eli Sudlow in the Great Seal Patent
Office on the 27th February 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ELI SUDLOW, of Oldham, in the County of Lancaster, Mechanical
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of August, in the year of our
Lord One thousand eight hundred and seventy-four, in the thirty-seventh
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said William Eli Sudlow, Her special licence that I,
the said William Eli Sudlow, my executors, administrators, and assigns,
or such others as I, the said William Eli Sudlow, my executors, admini-
strators, 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 ENGINES FOR
OBTAINING MOTIVE POWER AND FOR RAISING AND FORCING FLUIDS," upon the
condition (amongst others) that I, the said William Eli Sudlow, my
executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, 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.

page_text: NOW KNOW YE, that I, the said William Eli Sudlow, do hereby
declare the nature of my said Invention, and in what manner the same
is to be perfornied, to be particularly described and ascertained in and
by the following statement :-
These improvements relate to an Invention for which Letters Patent,
No. 272, were granted to me on the 23rd day of January 1873, and
have for their object the simplification of the rotary engine described
in the Specification of the said Letters Patent. In its improved form
I construct the cylinders forming the annular chambers of my rotary
engine without the steam jacket surrounding them, as heretofore; but
I retain the method described of mounting the piston or drum upon
the main driving shaft in order to allow for expansion, except in some
cases when I find it more convenient to mount the drum direct upon
the shaft and not upon an intermediate boss. The disc plates or flanges
secured to the ends of the drum are provided with a spring or piston 1
ring inserted in a suitable annular groove, and thus a more perfect and
steam-tight joint is produced. The reciprocating slide or shutter is also
differently constructed and actuated.
Instead of employing the piston with larger area on one side than
the other to actuate such slide I form a passage on the under side
or through the slide communicating with the interior of the cylinder,
and thus I permit the same pressure to be always exercised on the back
of the slide as obtains in the interior of the cylinder. A rod projects
from the back of this slide into a steam chamber in which the pressure
is constant, this steam chamber being fitted with a suitable equilibrium
or slide valve which by means of an eccentric or cam controlls the
admission of steam into the cylinder. The area of the rod is sufficient
to ensure the slide being kept in contact with the drum and the nose
of the slide, and the piston upon the drum are so formed that when the
drum revolves the piston portion of the drum coming in contact with
it gradually pushes the slide out of the way to permit it to pass, when
the pressure upon the back of the rod instantly causes the slide to
follow the incline on the back of the piston, and thus to close itself
against the revolving drum. And in order to ensure the slide being
steam-tight at either end I insert a brass packing in a suitable channel
formed in the slide, and which packing is forced outwards by the steam
pressure against the face of the discs or flanges of the drum; and I
further cover the ends of the recess in which the slide reciprocates

page_text: with special covers which are again enclosed by the ends or covers of
the cylinder.
This improved form of engine may also be made reversible with a
single slide by having steam passages formed through the slide, either
of which may be closed at pleasure by a suitable valve, according to
the direction in which it is required to run the engine, there being
two exhaust ports, either of which may be closed when the other is
open.
The improved construction of rotary engine herein-before described
may be driven by water or compressed air instead of steam, and is also
applicable to the purpose of raising and forcing various fluids, forming
an efficient rotary pump or blower, in which case it may cither be
driven from a line shaft in a convenient position, or direct by combining
it with one or more of my improved motive-power drums upon
'the same
shaft, thus forming a very compact arrangement.
Fig. 1 represents a plan partly in section of one modification of my
improved rotary engine; Fig. 2 is an end sectional view of Fig. 1
through the line a-b.
Fig. 3 is an end elevation, and Fig. 4, a side elevation of part of
Fig. 1, illustrating the mode of actuating the equilibrium valve; and
Fig. 4 shows a section of Fig. 4.
Fig. 5 is a sectional plan of a reversing rotary engine suitable for
driving the screw propeller of a steamboat in accordance with my
Invention; and Fig. 6 is an end sectional view of Fig. 5 through the
line c-d.
Fig. 7 is an exterior plan of another modification of my improved
rotary engine constructed without any special mechanism to actuate the
slide, which of itself cuts off and admits the steam; and Fig. 8 is an end
sectional view of Fig. 7 through the line e-ƒ.
Fig. 9 represents an end sectional view of part of a rotary pump or
air compresser constructed in accordance with
my Invention.
. . In all the views the same letters of reference are used to denote
similar parts.
A is the cylinder supported upon the bed plate Band provided with
flanges A¹ at each end, to which the end covers A² are secured by bolts.

page_text: These covers are constructed with an annular recess to exactly corre-
spond with an annular projection 'A' upon the cylinder, and thus such
covers form a support to the cylinder by encircling such projections and
at the same time by forming the pedestal for the driving shaft C ensure
such shaft remaining always in the exact centre of the cylinder. The
shaft C is encircled inside the neck portion of the end covers A3 by a
brass bush C³, and stuffing box joints C² are applied to such covers, as
illustrated. D is the piston drum, which is secured upon an enlarge-
ment C³ of the shaft C inside the cylinder (and which enlargement
corresponds to the intermediate boss H³ mentioned in my previous
Specification) by means of one or more feather keys D', and the ends of
this piston drum are provided with disc plates D², as in my former
Specification, but such disc plates in this case have a space left between
them and the end covers of the cylinder, into which space through the
passage the steam may obtain admittance together with the lubri-
cating material, the latter being supplied by the lubricator e. The
presence of this steam between the said discs and end covers not only
tends to remove the strain upon the screws which secure such disc
plates to the piston drum, but also serves to lubricate such disc plates
together with the shaft passing through the brass bushes; any lodgment
of water in this space may be removed through the cock f¹. It will be
noticed that such disc plates are supported and revolve upon an inner
extension A' of the end covers, and thus their bearing surface is
increased in closest contact to the drum where support is most needed.
The periphery or circumference of these disc plates D³ is constructed
with an annular rectangular groove in which two angular piston rings D³
are fitted, as illustrated, which ensure a steam-tight joint on all the
wearing surfaces of such annular groove and piston rings. The nose of
the piston has a parallel rectangular groove formed therein, into which
a metallic packing piece D' is fitted accurately, and to the back of
which the steam obtains admittance from the steam side and thus
presses such packing piece into contact with the cylinder. In pro-
portion to the pressure of steam at the various points in the revolution
of the piston drum this method of pressing up the packing picce prevents
such packing piece being forced out of position in passing between the
exhaust port and the point in the revolution of the drum at which the
steam is again admitted. Upon one side of the interior of the cylinder A
a rectangular recess is formed to receive a corresponding shaped slide E,
and the back of this recess communicates by means of a passage F and

page_text: through a double beat valve G with the steam chamber H in which the
steam pressure is constant, and a rod E¹ forming part of the slide E passes
through a stuffing box E³, as illustrated, into this steam chamber; and
thus by having the constant steam pressure exerted upon it ensures the
slide always being in contact with the piston drum D. I is the exhaust
pipo which communicates with the interior of the cylinder through a
series of holes J. Through the slide Ę passages E³ are formed (shewn
dotted in Figs. 1, 2, 8, & 9), to admit the steam into the cylinder at
one side of the slide, and the ends of this rectangular slide are fitted
with packing pieces similar to the packing piece in the nose of the
piston D. The ends of the rectangular recess in which the slide E is
situated are covered with the intermediate cover plates E' secured in
position by screws, shown dotted in Fig. 1; and these cover plates in
their turn are covered by an extension of the end covers A³ of the
cylinder, leaving a space for the admission of steam betweon the two
covers to ensure the same pressure on both sides of such cover plates.
K is a small cock communicating with the space K' at the back of the
slide recess for the purpose of blowing out any sediment or grit which
might otherwise accumulate at the back of the slide E.
The double beat valve G (see Figs. 1, 2, 3, 4, and 4*) is formed at one
end of the spindle G¹.which passes through a stuffing box G², and this ¯
spindle has a square G³ near its other extremity passing through a brass
bush L (seen in Fig. 4*) mounted in the bracket L', and at the farthest
extremity of the spindle G' a cam L' is secured, having two projections L³
on its inner face, and upon this brass bush a similar cam L' provided
with corresponding projections is mounted loosely. This latter cam has
an arm L depending from it, which is connected to a rod N having at
its other extremity a antifriction bowl N', which is kept in contact
with a spiral cutting-off cam O by a spiral spring surrounding such rod,
as seen dotted in Fig. 3. The spiral cutting-off cam O is mounted upon
the shaft C, and is capable of sliding thercon, being actuated by the
lever O', which may be secured in any position in the quadrant O³ by a
set screw 0%. Upon the same brass bush L and keyed securely thereto
is a lever handle P to be used for stopping or starting the engine, and
which may be locked in the two positions upon the adjustable disc
plate P¹ by the spring catch P' taking into two slots P³ provided for the
purpose in such disc plate.
The working of this engine may be thus described :—Steam pressure

page_text: being constant in the steam chamber H in starting the engine, it is only
necessary to open the double beat valve G, which is effected by moving
the handle P until the projections L³ upon the faces of the cams L'
and L* come in contact with one another, and so force cach other apart
and draw the spindle G³ in the direction of the arrow,
and thus open the
double beat valve G. Steam now finds its way through the passage F
to the recess at the back of the slide E, and from thence through the
passage E³ formed in the slide E into the interior of the cylinder A, as
indicated by the arrows. The piston D is thus forced round in the
cylinder until it passes the exhaust openings J, when the steam is free
to escape out of the cylinder through the said openings J and exhaust
pipe I, whilst at the same time the slide E is gradually forced by the
inclination upon the piston back D into its recess to permit the piston
to pass. Now as soon as the slide begins to follow the inclination on the
other side of the piston D the steam is again admitted.
The cutting off the steam in order to work the engine with a variable
expansion is regulated as follows:-By moving the lever O' the spiral
cutting-off cam O slides along the shaft C, and thus presents a longer or
shorter portion of its greatest diameter to the bowl N¹ at the extremity
of the spring rod N, and thus cuts off the steam accordingly. It should
be here remarked that this cutting-off cam always admits the steam at
the same point in the revolution of the piston, viz., at that instant when
the slide commences to return into the cylinder after being pushed back
into the recess, and this is effected by the entire front edge O³ of the
cam O being in a parallel line with the axis of the shaft C, whilst the
other edge of the cam, which is marked O', is arranged in a spiral
direction, and thus allows the bowl N¹ to run down it sooner or later,
according to the position of such cam on the shaft C.
.
Instead of this spiral cam I sometimes employ an eccentric for working
the double beat valve when the amount of expansion at which it is
desired to work the engine can be definitely fixed, and it will be readily
apparent that in this case a slide valve and rocking spindle may be
substituted for the double beat valve and sliding spindle; this arrangement
being advisable in case of winding engines, steam cranes, or other
engines which require frequently to be reversed.
In Figs. 5 and 6 the slide E is arranged with two distinct sets of
passages formed through it, each fitted with a slide valve, and the cylinder
is provided with two exhaust passages for the purpose of working the

page_text: engine in both directions. The exhaust passages R and R', which
communicate with the interior of the cylinder through the passages S
and S', are fitted with tapered plugs after the manner of a plug cock,
and such plugs are fitted with internal spindles connected together by
arms and a connecting rod, as seen dotted in Fig. 6, in order that only
one of such passages shall be open at a time, the lever T secured upon
one of the spindles of the plugs, as illustrated, serving to reverse such
plugs at pleasure, in order to change the direction of the engine whilst
the set screws T₁ are for keeping the plugs in position. The Drawings
represent the plug in the passage R as closed, and that in R' as open.
In Fig. 5, the slide E is shewn with its top plate removed, shewing
the ports leading to the openings into the cylinder on both sides of the
slide E, and in the adjoining detached view this slide is shewn in section.
a, a, are the ports leading to the passages, having their outlets in the
upper side, and b, b, are the ports leading to the passages opening
through the under side of the slide, whilst the central space c, c, com-
municates with either port through the slide valve d, d, and with the
steam chamber H through the opening e, e, shewn dotted in Fig. 5.
These slide valves set themselves self-actingly according to whichever
exhaust passage is open, owing to the greater pressure on one end of
such slide valves than on the other, and in the same manner the small
double beat valvef for controlling the admission of steam to the back
of the packing piece in the nose of the piston closes one of two
passages or h, according to the direction in which the engine is
running. It will thus be apparent that to change the direction in
which this engine is running it is only necessary to move the lever T,
and so to reverse the plugs in the exhaust passages. The double beat
valve G is employed in this as in the other modifications, being actuated
in a similar manner to that described in reference to Figs. 1 and 2;
but in this case it will be requisite to have a pair of spiral varying
cut-off cams set in reverse directions upon the driving shaft, and
either of which cams may be brought into play with the lever O',
according to the direction in which it is required to run the engine.
This construction of rotary engine when applied to work the pro-
pellor of a steamboat," affords an advantage in permitting the thrust
bearing to be placed at the end of the shaft, as seen in Fig. 5, where a
series of slightly convexed discs 1, 1, are placed at the end of the shaft
in a suitable socket j, either or all of which may revolve according to

page_text: .
the degree of friction put upon them; this extremity of the shaft being
slightly reduced in diameter from the point k where it enters the socket,
at which point the thicker part of the shaft makes a tight joint, the
tightness of this joint being still further ensured by the use of a stuffing
box for the purpose of enabling a supply of oil or other lubricant to
be pumped into the socket j, by means of the pump m actuated by the
eccentric n. The pipe o of this pump is provided with a safety valve,
the load of which can be regulated to suit the amount of thrust. It
will thus be seen that this end of the shaft answers to the ram of a
hydraulic press, and that thus the friction upon the end of such shaft
can be regulated to the greatest nicety. The ordinary thrust bearing p
is in this case also situated behind the engine for the purpose of taking
the pull when running astern, but the rings q are turned in the ordinary
diameter of the shaft, as illustrated, instead of being upon an enlarge-
ment of the diameter of the shaft as heretofore.
In the engine represented in Figs. 7 and 8, the slide E acts as a valvo
for cutting off the supply of steam when run back into the recess as the
mouth of the passage F is placed more forward and is covered by the
slide E, so cutting off the steam at the instant that the piston is passing
the mouth of the exhaust and the recess, which when once passed leaves
the slide at liberty to re-enter the cylinder, so uncovering the steam port
again. This engine requires no eccentric or cam to controll the admission
of steam as in the previous modification. The wheel valvo y being
simply used for shutting off or admitting steam. This form of engine
being more particularly useful for working with compressed air or liquid
when it is not required to work expansively.
Fig. 9 represents a pumping engine, which as far as the cylinder and
slide is concerned is the same as the previous modification (Figs. 7
and 8), but in this case the passage S forms the suction pipe, and the
passage t the delivery pipe, which latter is fitted with a back pressure
valve u and air vessel 10, the small pipe x serving to admit the pressure
(either liquid or gaseous) into the chest y' in order to actuate the slide
by pressure acting upon its rod as herein-before described with reference
to the previous modifications, or this pressure may be imparted by con-
necting such chest y¹ to steam or any other source of pressure for the
same purpose. This engine is not self-acting but requires to be driven
by an motive power in a reverse direction to the engine, shewn and
described in reference to Figs. 7 and 8.

page_text: Instead of the form of piston shewn in the several views it should bo
stated that such pistons may be in the form of a perfect drum mounted
eccentrically, as shewn dotted in Fig. 8; and instead of having the
slide E to work horizontally, as illustrated on the several views, it may
be mounted vertically in its recess on the top of the cylinder, in which
case the rod E' would be dispensed with, and such slide would then
follow the piston by its own gravity.
Having thus particularly described and ascertained the nature of this
my said Invention, together with the best methods with which I am
acquainted for carrying the same into practical effect, I wish it to be
understood that I do not confine myself to the precise details, relative
proportions, or dimensions of the various parts of the engines, illustrated
on the accompanying Drawings, and herein-before described, as the same.
may be considerably varied without departing from the Invention, and
what I particularly claim is,-
1st. The general construction and arrangement of rotary engine,
illustrated on the accompanying Drawings and hercin-before described.
2nd. Forming grooves in and applying metallic packing rings to the
disc plates attached to the piston drum, together with the special con-
struction of end covers to the cylinders, leaving a space for the admis-
sion of steam on the outer side of the disc plates, as and for the purpose
described and illustrated on the accompanying Drawings.
3rd. The slide E in the various engines, illustrated on the Drawings
when constructed, rendered steam-tight, and operated, substantially as
herein-before described.
4th. The variable cut-off motion, illustrated in Figs. 1 to 4 inclusive,
for controlling the admission of steam to rotary engines working expan-
sively, as herein-before described.
In witness whereof, I, the said William Eli Sudlow, have hereunto
set my hand and seal, this 26th day of February 1875.
WILLIAM ELI SUDLOW. (L.S.)