IMPROVEMENTS IN ROTARY ENGINES
Year: 1884

page_text: COMPLETE SPECIFICATION.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of the said Invention for IMPROVEMENTS
IN ROTARY ENGINES and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
This Invention consists of a wheel that has a semi-circular groove in the face,
and running within a stationary ring also having a semi-circular groove which
together with the groove of the wheel, forms the cylinder or steam-way. The
wheel carries the pistons which are fixed in the wheel, and the abutments are
arranged in the stationary ring to slide forward and backward for allowing the
cylinder behind them to hold the steam; the slide valves are employed to shut off
the steam while the abutments are shifting, and said valves and the abutments are
operated by cams on the shaft of the wheel; the whole being constructed and
arranged in a simple manner and adapted to provide an efficient rotary engine of
large radius for developing great power with slow motion, all as hereinafter fully
described.
Reference is to be had to the accompanying Drawings forming part of this
Specification in which similar letters of reference indicate corresponding parts in
all the Figures.
Figure 1 is a sectional plan view of the improved rotary engine, the upper part
of the ring being removed, and parts being shown in section. Figure 2 is a side
view of the same, parts being broken out. Figure 3 is a longitudinal sectional
elevation of the same. Figure 4 is a cross sectional elevation of the same.
Figure 5 is a face view of the cams for operating the slide valves. Figure 6 is a
face view of the cams for operating the sliding abutments. Figure 7 is a detail
sectional plan view showing the arrangement of the abutments, parts being broken
out. Figure 8 is a sectional plan view of the cylinder containing the abutments,
Price 1071

page_text: showing the arrangement of the valve for the reversing gear. Figure 9 is a like
sectional view showing the arrangement for starting the machine if it stops on a
dead centre. Figure 10 is a sectional view of the same on the line y y Figure 9.
A transverse horizontal shaft A is journalled on a frame B and on the said
shaft A a wheel C is mounted which is provided in its rim with a semi-circular
annular groove C¹. The wheel C is surrounded by a cylindrical casing D, provided
in its inner surface with an annular semi-circular groove D¹ which groove D'
combined with the groove C¹ forms the annular cylinder of the engine. On the
wheel C one or more pistons E are held, which have their outer ends made semi-
circular so as to fit closely against the groove in the casing D, the said pistons being
provided on their ends with semi-circular packing strips E¹. The inner ends of
the pistons pass through the rim of the wheel C and are held in place by keys C³.
Diametrically opposite each other, the casing D is provided with two extensions or
steam chests D' which are also supported by the frame B and form part of the
same. A steam pipe F extends to each chest, the said steam pipes F being
connected by means of a common pipe F¹ with the boiler. Each steam chest D' is
provided with a chamber D³ containing an abutment G adapted to slide in the
horizontal plane in the direction toward and from the rim of the wheel C. The
said abutment is formed of a block provided with a top and bottom plate. The
inner end of the block is provided with a semi-circular recess, and in the same a
disc G₁ is placed, which is surrounded by packing rings G having diagonally
opposite end lugs G which rest against shoulders formed on the end of the block G.
The top and bottom plates are placed on the top and bottom surfaces of the block,
and the plates and blocks are held together by bolts passed through them. The
disc G' is held in place by a heavy bolt g³ passed through the plates and through
the said disc, and having a head on each end.
The ends of the top and bottom plates of the abutment are provided with
shoulders coinciding in position with the side lugs Ge of the packing rings G³ for
the purpose of causing the inner end of the abutment to fit snugly against the
bottom of the groove C¹ in the wheel C and against the surface of the annular
flanges formed at the sides of the groove. On the outer surface of the wheel O
plates C are secured which pass through grooves or notches C³ in the end of the
abutment and in the end of a packing plate Cheld between one side of the
abutment and the side of the chamber, which plate is pressed against the side of
the abutment by a spring at held between the said block or plate and the side of
the chamber, whereby the abutment will be packed closely and any leakage of steam
will be prevented. Packing strips G' pass through the slots in the top and bottom
of the steam chests which are pressed against the top and bottom surfaces of the
sliding abutment G and are held in place by screws G* held in cross pieces on the
steam chests.
The casing D is provided with four outlets a a and b b for exhaust steam, the
said outlets being arranged in pairs, the outlets of each pair being diametrically
opposite each other. The said outlets are connected with suitable pipes for carrying
off the steam. Each steam chest D' is provided with a chamber d into which the
steam from the pipes F is conducted in which chamber a slide valve d¹ is located,
which is connected with the connecting rod d' passing through a stuffing box in
the inner end of the steam chest. From the said chamber da channel c conducts
the steam into a vertical channel e connected at its top by a channel fand at its
bottom by a channel f¹ with the recesses g and g¹ formed respectively above and
below the sliding abutment in the surface of the chest, as is clearly shown in
Figure 8. A piston H fitted in the channel e and adapted to work in the same is
secured to a rod H¹ projecting through a stuffing box in the top of the steam chest
and connected with an arm I of a horizontal shaft I parallel with the side of the
casing D. A channel is connected by a channel i with the channel e at the
centre of its height, and the said channel h contains a piston h¹ secured to a piston
rod h projecting through a stuffing box in the top of the steam chest D', which

page_text: 'connecting rod h³ has its upper end pivoted to a lever h³ pivoted on a standard h
on the top of the stuffing box whereby the said piston h¹ can be worked up or down
by means of the said lever h. Each abutment G is provided at its inner end with
a lateral projection J to which a connecting rod J' is fastened, which passes
through a suitable stuffing box in the inner end of the steam chest. The connecting
rods d to which the slide valves d' are fastened have their opposite ends pivoted to
levers K pivoted on clips K¹ secured on the top plate B₁ of the frame of the
machine in such a manner that the said levers K can be acted on by a series of
cams kand, Figure 5, formed on a sleeve L loosely mounted on the shaft A and.
provided in its inner surface with a segmental groove L' into which a stud L'
projecting from the shaft passes, so that when the shaft A is reversed there will be
the lost motion of about one-third of the circumference of the shaft before the
sleeve is revolved by the shaft, that is, if the sleeve is revolving in one direction and
the machine is reversed, the sleeve is not revolved during the time that the stud L'
passes from one end of the segmental groove L' to the other end of the said groove.
There are as many cams k and as many cams as there are pistons in the engine.
The connecting rods J¹ connected with the lateral projections of the abutments are
connected by suitable links J' with levers M, pivoted on clips M², in the platform B',
which levers M are provided at their pivoted ends with T heads M² the straight
edges of which face the sleeve N mounted on the shaft A in such a manner that
it turns with the shaft, but can slide in the direction of the length of the same.
On one end of the gleeve N three cams n are formed which are separated by like
distances from each other, and on the opposite end of the sleeve N a disc N' is
formed on the inner surface of which three cams n' are formed, also separated by
like distances from each other. The cams n¹ are adapted to act on the outer ends
of the heads M² or those ends of the same in the direction from the casing D, and
the cams n are adapted to act on the inner ends of the heads M², that is, on the
ends toward the casing D. Springs m are secured on the platform B' in such a
manner that their free ends can press against the swinging ends of the levers M
thereby pressing the inner ends of the heads M' against the cams n. Springs m¹
projecting in the opposite direction to the springs m are so arranged that their free
ends can press against the levers M near their pivots, thereby pressing the outer
ends of the heads M* against the cams n¹.
The sleeve N is provided with an annular groove o into which the prongs O' of a
forked lever O pass, which lever is pivoted on suitable standards on the frame of
the machine whereby by shifting the said forked lever, the sleeve N can be shifted.
in such a manner that the cams n' can act on the outer ends of the heads M³,
can be shifted in such a manner that the cams n can act on the inner ends of the
heads M².
or it
The shaft I previously mentioned is provided with an upwardly projecting arm P
which is connected by a connecting rod Pl with the upper part of the lever O.
The casing D is provided in its inner edge at each side of the semicircular groove D¹
with an annular groove Q, containing a packing strip R, the edge of which rests on
flanges formed on the rim of the wheel C at the sides of the groove C¹. The inner
edges of the packing strips R are pressed against the flanges of the wheel C by
screws S held in the casing D.
The operation is as follows: The steam enters the chamber d from the pipe F
and then passes through the opening c into the channel e and from the same
through either the channel for f1 into the annular cylinder. If steam enters the
cylinder through the upper channel f, g, the wheel will be revolved in the direction
of the arrow & the steam abutting against the abutment G. When the piston E
arrives at the exhaust a the steam escapes. The slide valves d are operated by
the cams kand k¹ and are thus reciprocated, admitting steam and cutting it off
alternately. The cams n acting on the inner ends of the heads M' of the levers M
operate the rods J whereby the abutments will be reciprocated thus alternately
they will be pressed against the bottom of the groove C¹ and withdrawn from the

page_text: same. When the abutments project from the steam chest, they act as abutments
for the steam, but they must be withdrawn at suitable intervals to let the pistons
pass, and must then be pushed back again. If the engine is to be reversed, the
steam must enter the annular cylinder through the bottom channel f¹ g¹, and act
on the piston below the abutment, whereby the wheel will be revolved in the
direction of the arrow w. This is accomplished by swinging the lever O outward,
that is, from the casing D, whereby the shaft I will be turned in such a direction
as to swing the arm I¹ upward and raise the corresponding valve H whereby
communication between the top channel f and the chamber d will be cut off.
the same time the sleeve N is moved toward the casing D so that the cams n¹ can
act on the outer ends of the heads M' of the levers M. The engine can thus
be reversed at any time by simply throwing the lever O in one direction or
the other.
At
I wish to call attention to the fact that when the steam enters the steam
oylinder through the top valve g at one side, it must enter through the bottom
valve g at the other, and vice versa, when it enters the steam cylinder through the
bottom valve g¹ at one side it must enter through the top valve gl at the other;
and therefore the parts must be so arranged that when the valve H is raised in one
steam chest the valve H in the other must be lowered and for that reason only one
valve rod H¹ is operated directly by an arm I as is shown on the right hand side
of Figure 1 but the other valve rod H¹ is operated by a forked lever I pivoted on
the standard on the platform B¹ and pivoted to a short arm I¹ of the shaft I as
shown on the left hand side of Figure 1 and in Figure 4.
As stated above, the sleeve L' on which the cams k k¹ are formed is mounted
loosely, and when the engine is reversed the shaft makes one-third of a turn before
the said sleeve is revolved, and during this time no steam could pass into the
engine, as the slide valves are not used. To avoid this difficulty, the levers h³ are
raised, whereby the valves h¹ in the channels h are raised, the steain can thus pass
directly from the steam chamber d into the channels h through the channels i into
the channels e and from the same through one of the channels for f¹ to the
recess g or g¹ and into the cylinder. As soon as the shaft is revolved sufficient to
cause the projection or lug L to engage with one end of the groove L in the
sleeve L, the valves are operated in the usual manner.
The improved engine is thus so constructed that when the engine is to be
reversed not only the valves for governing the moving parts of the machine are
reversed but the steam inlets are also reversed.
In case three pistons are to be used and the machine is to be arranged to revolve
in one direction only, but two exhaust ports are used which are arranged
diametrically opposite each other at the top and bottom of the circular cylinder.
Having now particularly described and ascertained the nature of the said
Invention, and in what manner the same is to be performed, I declare that what
I claim is:
1 In a rotary engine, the combination with a wheel having a semi-circular
groove in its rim, of a fixed casing surrounding the wheel and provided with a
semi-circular groove in its inner surface, which casing and wheel together form an
annular steam cylinder, pistons projecting from the rim of the wheel and fitting
against the groove in the casing, one or more sliding abutments held in steam chests
formed in the casing, and valves for regulating the admission of steam into the
cylinder, substantially as herein shown and described.
2nd In a rotary engine, the combination, with the cams k and k on the shaft A
of the levers K, K and the rods d' connected with the said levers and with the
sliding valves in the steam chest, substantially as herein shown and described.
3rd In a rotary engine, the combination with the cams on the shaft of levers
dapted to be acted upon by the said cams, abutments sliding toward and from the
shaft in suitable steam chests and rods for connecting the said abutments with the
above mentioned levers substantially as herein shown and described.

page_text: 4th In a rotary engine the combination with a shaft of a sliding sleeve provided
at its opposite ends with two different sets of cams, levers adapted to be acted
upon by either set of cams, and rods connecting the said levers with sliding
abutments in the steam chests, substantially as herein shown and described.
5th In a rotary engine the combination with a revolving wheel having pistons
of sliding abutments held in the steam chests at the side of the wheel, two different
sets of cams. on the shaft of the wheel, which cams act on levers connected with
the sliding abutments, and of devices for shifting the cam sleeve so that either set
of cams will act on the sleeve, whereby the movements of the cams can be reversed
as the engine is to be reversed, substantially as herein shown and described.
6th In a rotary engine, the combination with a shaft carrying a wheel provided
with pistons a sliding sleeve mounted on the shaft and provided at its ends with
different cams, levers acted upon by the cams, abutments connected with the said
levers and sliding in suitable steam chests, valves for admitting the steam above or
below the abutments, and means for automatically adjusting the said valves at the
same time that the cams on the shaft are adjusted, substantially as herein shown
and described.
7th In a rotary engine the combination with the wheel C, mounted on the
shaft A of the sliding sleeve N, mounted on the shaft and provided with different
sets of cams at its ends, the levers M connected with sliding abutments G, the
steam chests D³ having channels e and the channels f f¹, the piston H sliding in
the channel e, the shaft I, arms for operating the piston H from the shaft I and
means for operating the shaft I at the same time that the sleeve N is shifted,
substantially as herein shown and described.
8th In a rotary engine, the combination with the shaft of the sleeve L carrying
the cams kk and provided in its inner surface with a semi-circular groove L¹ and
the stud L projecting from the said shaft into the groove L³, substantially as
herein shown and described.
9th In a rotary engine, the combination with the steam chests having the
channels e and the channels f f¹ leading to the steam cylinder of the piston H, the
piston rod H¹, the piston or valve h¹ in the chamber h which is connected by
the channel with the chamber e and which chamber h is also connected by a
channel with the chamber d into which the steam is admitted and of a lever for
raising the valve h³ substantially as herein shown and described.
10th In a rotary engine, the combination with the wheel C having a semi-circular
groove (in its rim, of the casing D, the sliding abutment G, provided with a
dise G surrounded by a packing ring Go and having lugs Ge forming shoulders
fitting against the flanges on the rim of the wheel, substantially as herein shown
and described.
11th In a rotary engine, the combination with the wheel C carrying pistons of
the casing D, and the steam chests D' formed on the same, substantially as herein
shown and described.
12th In a rotary engine, the combination with a wheel C of the casing D having
a segmental groove D¹ in its inner surface, a groove Q, formed at each side of the
groove D¹, packing strips R in the grooves Q, and of screws S, substantially as
herein shown and described.
13th In a rotary engine, the combination with the grooved wheel C of the
casing D, the pistons E, fixed in the wheel, the sliding abutments G, sliding valves,
and cams for operating the valves and cams, substantially as herein shown and
described.
14th In a rotary engine, the combination with the grooved wheel C and the
casing D of the pistons E held detachably on the said wheel, substantially as herein
shown and described.
15th In a rotary engine the combination with the pistons E consisting of blocks
having semi-circular ends, and of packing strips held in the said blocks, substan-
tially as herein shown and described.

page_text: 16th In a rotary engine, the combination with a shaft of cams on the same levers
adapted to be acted upon by the cams, sliding valves and sliding abutments
connected with the said levers, and of springs acting on the said levers, substantially
as herein shown and described.