IMPROVEMENTS IN ROTARY ENGINES
Year: 1882

page_text: LETTERS PATENT to Alexander Melville Clark of the firm of A. M and
W Clark of 53 Chancery Lane in the County of Middlesex, Patent Agents
for an Invention of IMPROVEMENTS IN ROTARY ENGINES communicated
to him from abroad by George Willason Wade and Joshua Mearue Wardell,
both of Cadillac in the County of Wexford and State of Michigan, United
States of America.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark
at the Office of the Commissioners of Patents on the 21st November 1882.
ALEXANDER MELVILLE CLARK of the firm of A. M and W. Clark of 53 Chancery
Lane in the County of Middlesex Patent Agents
" IMPROVEMENTS IN ROTARY
ENGINES [communicated to him from abroad by George Willason Wade and
Joshua Mearue Wardell, both of Cadillac in the County of Wexford and State
of Michigan, United States of America.]
"
This Invention is an improvement upon that description of rotary engines in
which the case of the engine is of ellipsoidal shape in the cross section and
drawn in at the sides of its shorter diameter, with adjustable packings fitting
recesses in said drawn in sides to form a close working joint, with a radially
slotted revolving cylinder that forms a central steam chest and is provided with
revolving heads that close in opposite ends of the case and with a series of radially
sliding pistons pressed outward by the steam and against the faces of which the
steam acts to rotate the cylinder. The Invention consists in a novel arrangement
of reversing valves and passages and means for operating the same to change the
direction in motion of the engine, by admitting steam to opposite sides of the
pistons. The Invention also consists in a combination, with the revolving hollow
cylinder and its radially sliding pistons or valves and passages therefor, of circular
cut-off valves having their axis of motion coincident with that of the cylinder,
for working the engine under different degrees of expansion.
Steam is admitted to the revolving cylinder which is constructed to form a
central steam chest or chamber by a central attached revolving pipe and branch
connected with a hollow bearing. The heads at the ends of the cylinder are
extended so as to enclose the ends of the working case of the engine said heads
rotating in common with the cylinder, central steam pipe and engine shaft.
Outside of these heads, one of which is made removable are stationary enclosing
caps secured to the heads of the case to prevent external leakage.

page_text: There are four equi-distant radially sliding valves or pistons for the purpose of
producing a better balancing effect arranged within corresponding slots in the
cylinder which slots are in communication at their inner ends with the steam
chamber of the cylinder.
Arranged within the steam chamber so as to control the inner terminations or
inlets of the slots are two opposite circular or segmental cut-off valves that may
be loosely fitted on the ends of a cross-bar which is carried by a shaft or spindle
coincident with the axis of the cylinder and extending through the steam supply
pipe and bearing the valves being controlled by a lever on the outward end of
the shaft. The steam is admitted by the inlets to act upon the pistons for the
purpose of propelling the engine, and the cut-off valves serve to cut off the steam
at any desired point, for the purpose of working the steam expansively within
the case.
These valves remain stationary, when the engine is running, but in
starting they are moved by the lever sufficiently to allow the engine to take steam
to start it, after which they are put in proper position and secured.
The pistons are made solid and the slots in which they work connect on their
opposite sides with recesses or valve chambers in which are fitted a pair of
reversing valves for each piston. From each pair of valve or piston chambers
angling ports or passages diverging outwardly project to and through the circum-
ferential exterior of the cylinder. The valves of each pair are so set and
arranged that when one valve closes the passage which it controls, the other valve
uncovers its port, and accordingly as each of said ports is opened or closed, is the
engine reversed by changing the admission of steam to the opposite sides or faces of
the pistons. The valves are operated by their connection through rods with a ring
that rotates in common with the cylinder, and which is slid in or out over the
central pipe by a lever and clutch rod within which the ring revolves.
To provide for reversing the engine as described, each side of the engine has
duplicate exhaust ports and branches or pipes arranged to communicate with the
case_at a sufficient distance apart above and below or on opposite sides of the
packings corresponding with the diverging ends of the ports. These duplicate
exhaust ports and branches must be closed on one side of the engine, and opened
on the other, according to the direction in which the engine is being run by the
adjustment of the reversing valves.
Instead of the steain pipe being made to revolve, it may be stationary and a
stuffing box in the head be fitted to revolve around the pipe.
According to a modification a steam jacket is substituted for the two exhaust pipes
with which the exhaust ports on opposite sides of the case separately connect said
jacket being arranged to extend around the case for the exhaust steam passing out
by any of the ports to enter the steam finally escaping by a single outlet or pipe.
Instead of constructing and arranging the cut-off valve within the steam
chamber to cut off the steam at any desired point by adjusting them in a circular
direction around their longitudinal axis, the valves with their attached shaft are
adjusted longitudinally, relatively to the chamber to cut off the steam at any
desired point, the ends of the valves being suitably shaped for the purpose, and the
hand lever being attached to the shaft so as to slide it longitudinally instead of
turning it as herein before described.
Either form of cut-off valve may be used, their principle of action and
arrangement being the same, and if desired the shaft which controls them may
be actuated by a governor instead of by the hand lever thus making said valves
automatic.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alexander Melville Clark in the Great Seal Patent Office on the
21st May 1883.
ALEXANDER MELVILLE CLARK of the Firm of A, M, and W, Clark of 53 Chancery
Lane in the County of Middlesex Patent Agents IMPROVEMENTS IN ROTARY
ENGINES A communication to me from abroad by George Willason Wade and
Joshua Mearue Wardell, both of Cadillac in the County of Wexford and State of
Michigan, United States of America.
This Invention is an improvement upon that description of rotary engines in
which the case of the engine is of ellipsoidal shape in its cross section and drawn
in at the sides of its shorter diameter with adjustable packings fitting recesses in
said drawn in sides to form a close working joint, with a radially slotted revolving
cylinder that forms a central steam chest and is provided with revolving heads
that close in opposite ends of the case and with a series of radially sliding pistons
pressed outward by the steam, and against the faces of which the steam acts to
rotate the cylinder.
The Invention consists in a novel arrangement of reversing valves and passages
and means for operating the same to change the direction in motion of the engine
by admitting steam to opposite sides of the pistons, of which there are four equi-
distant ones for the purpose of producing a better balancing effect. The Invention
also consists in a combination with the revolving hollow cylinder and its radially
sliding pistons or valves and passages therefor, of circular cut off valves having
their axis of motion coincident with that of the cylinder for working the engine
under different degrees of expansion.
The Invention is illustrated in the accompanying drawings in which similar
letters of reference indicate corresponding parts in all the figures. Figure 1 is a
sectional side elevation of the engine with parts broken away to exhibit other
parts, and Figure 2 is a central vertical section of the same in a plane at right
angles to Figure 1. Figure 3 is a side view of the engine with one of its heads
removed, and with certain of its parts broken away, also showing the case of the
engine as enclosed by an exhaust steam jacket and a modified construction of the
cut off valves. Figure 4 is a central vertical section of the same in a plane at
right angles to Figure 3, and Figure 5 an interior face view of one of such inodified
cut-off valves detached.
Referring in the first instance to Figures 1 and 2, A is the ellipsoidal shaped case
drawn in at the sides of its shortest diameter and fitted with adjustable packings 8
to make a close joint with the revolving cylinder B which is constructed to form a
central steam chest or chamber B¹ to which steam is admitted by a central attached
revolving pipe C and branch D connected with a hollow bearing E. F G are the
heads at the ends of the cylinder B and extended so as to enclose the ends of the
working case A, said heads rotating in common with the cylinder, central steam
pipe C and engine shaft H. Outside of these heads, one of which is made
renovable, are stationary enclosing caps II secured to the beads of the case to
prevent external leakage. J J are the radially sliding valves or pistons of which
there are four arranged at equal distances apart within corresponding slots b b in
the cylinder B, which slots are in communication at their inner ends with the
steam chamber B' of said cylinder. Arranged within the steam chamber B', so as
to control the inner terminations or inlets b¹ of the slots b, are two opposite
circular or segmental cut-off valves K K that may be loosely fitted on the ends of
a cross bar d'which is carried by a shaft or spindle e that is coincident with the

page_text: axis of the cylinder B and extends through the pipe C and bearing E. These
The
valves K K are controlled by a hand lever f on the outer end of the shaft e.
steam is admitted by the inlets b¹ to act upon the pistons J J for the purpose of
propelling the engine, and the cut-off valves K K serve to cut off the steam at any
desired point for the purpose of working the steam expansively within the case A
These valves K K remain stationary when the engine is running, but in starting
they are moved by the lever f sufficiently to allow the engine to take steam to
start it, after which they are put in proper position and secured.
h
The pistons J J are made solid, and the slots b b in which, they work connect
on their opposite sides with recesses or valve chambers g g in which are fitted a
pair of reverting valves M M for each piston J. From each pair of valve or piston
chambers g g angling ports or passages h h diverging outwardly project to and
through the circumferential exterior of the cylinder B. The valves M M of each
pair of valves are so set and arranged that when one valve closes the passage
which it controls, the other valve uncovers its port h and accordingly as each of
said ports is opened or closed, is the engine reversed by changing the admission of
steain to the opposite sides or faces of the pistons J J. Said valves M are operated
by their connection through rods ii with a ring k that rotates in common with the
cylinder B and which is slid in or out over the central pipe C by a lever land clutch
rod m, within which the ring & revolves.
To provide for reversing the engine as described, each side of the engine has
duplicate exhaust ports and branches or pipes n N arranged to communicate with -
the case A at a sufficient distance apart above and below or on-opposite sides of the
packings 88 corresponding with the diverging ends of the ports h h. These
duplicate exhaust ports and branches n N must be closed on one side of the engine
and opened on the other, according to the direction in which the engine is being run
by the adjustment of the reversing valves M M.
Instead of the steam pipe C being made to revolve, it may be stationary and a
stuffing box in the head be fitted to revolve around the pipe.-
Referring to Figures 3. 4. and 5 of the drawings, the general construction of the
engine as shown by like letters referring to like parts, the same as that shown in
the previous figures hereinbefore described, with two exceptions only. The first
modification consists in substituting for the two exhaust pipes N N (Figures 1
and 2) with which the exhaust ports n n on opposite sides of the case A separately
connect, a steam jacket N' (Figures 3 and 4) arranged to extend around the case A,
and into which the exhaust steam passing out by any of the ports n n enters, and
from which it finally escapes by a single outlet or pipe n'. The other modification
has reference to the cut-off valves K K in Figures 1 and 2 arranged within the
steam chamber B¹ for working the steam expansively in the case A. Instead of
constructing and arranging these valves to cut off the steam at any desired point
by adjusting them in a circular direction around their longitudinal axis,
valves K K (Figures 3. 4. and 5) are used, which valves are made to similarly fit
the chamber B to control the steam inlets b₁, and are attached by a cross bar d to
the shaft e which also has its axis coincident with that of the cylinder, but said
valves K' K' with their attached shaft are adjusted longitudinally relatively to
the chamber B' to cut off the steam at any desired point, the ends of the valves
being suitably shaped for the purpose and the hand lever f being attached to the
sunft e so as to slide it lo gitudinally instead of turning it, as herein before
described. Either form of cut-off valve K or K' may be used, their principle of
action and arrangement being the same, and if desired the shaft e which controls
them may be actuated by a governor instead of by the hand lever f, thus making
Baid valves automatic.
Having described the nature of the said Invention and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
herein before in part recited Letters Patent is.
1 The combination of the cut-off valves K K' with the revolving cylinder B
having a central steam chamber B' radially sliding pistons J and ports or inlets bl

page_text: for passage of the steam through the cylinder to act upon the sides or faces of the
pistons and the ellipsoidal case A, substantially as described.
2nd The combination with the revolving cylinder B having a central steam
chamber B' and ports or inlets b of the cut-off valves K or K' and their attached
shaft e having its axis coincident with that of the cylinder, essentially as and for
the purposes herein set forth.
3rd In a rotary engine having a hollow revolving cylinder fitted with radially
sliding pistons for operation within a fixed case of varying diameters and having
duplicate exhaust ports nn on opposite sides of it, the combination of the reversing
valves M M with the revolving cylinder B having a central steam chamber B,
ports or inlets 6', radial slots b for the pistons, recesses or chambers 9 g for the
valves M M on opposite sides of the slots, and outwardly diverging passages h h
from said chambers, essentially as shown and described.
4th The combination with the revolving ring k, clutch rod m, lever l, and rods i
with the reversing valves M M, the revolving heads F. G and their attached
revolving cylinder B having radial piston slots b, inlets b¹, reversing valve
chambers g g on opposite sides of said slots, and outwardly diverging ports or
passages from said chambers g g substantially as specified.
In Witness whereof I the said Alexander Melville Clark have hereunto set
my hand and seal this twenty first day of May, A.D. 1883.