Improvements in Rotary Engines.
Year: 1890

page_text: Date of Application, 7th Jan., 1890-Accepted, 15th Feb., 1890
COMPLETE SPECIFICATION.
Improvements in Rotary Engines.
1, 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 this invention (a communication to me
from abroad by Thomas Richard Almond, Machinist, of No. 83, Washington Street,
Brooklyn, County of Kings and State of New York, and Edwin Gale Freligh,
Physician, of No. 11, West 34th Street, in the City, County, and State of New York,
United States of America) and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
Rotary engines, having eccentrics or cranks mounted upon the main shaft, are
subject to numerous objections of a practical nature which have prevented their
universal adoption. Thus, for example, the ends of the eccentrics are liable to
produce rough or grooved surfaces by their contact with the cylinder head owing to
the perfect steam-tight connection required and because the surfaces move upon one
another in the same continuous path. Those parts of the eccentric which are farthest
removed from the shaft tend to wear the cylinder-heads more rapidly on account of
their greater velocity thus producing, after a short run, depressions which render the
preservation of a steam-tight joint impossible. Many other objections, not necessary
here to state, may be cited against the use of rotary engines, all of which it is the
object of this invention to overcome. In fact, the invention has been subjected to
practical and satisfactory tests, and for that reason I deem myself justified in stating
that it overcomes all practical objections that can be raised to the introduction of a
rotary engine. The invention consists in the details of improvement and combina-
tions of parts which will be more fully hereinafter set forth and specifically pointed
out in the claims.
Reference is to be had to the accompanying drawings, forming part of this
specification, wherein figure 1 is an end elevation of the improved rotary engine.
Figure 2 is a horizontal section of the same, the line c-c figure 3 indicating the
plane of section. Figure 3 is a vertical section on line kk figure 4. Figure 4 is a
longitudinal vertical central section on line c¹ c' figure 1. Figures 5, 6, 7, and 9,
are detail-views of parts of the engine, hereafter more fully referred to. Figure 8
is a vertical central section of a single engine containing the improvements.
Figures 10 to 17 relate to improvements in various details of the rotary engine
shown in figures 1 to 9; figure 10 representing a side elevation of the improved
rotary engine; figure 11 a vertical longitudinal central section of the same;
figure 12 a cross-section on line k-k figure 11; figure 13 a cross-section on
line kk' figure 11; figure 14 a detail side view of an improved disc for adjusting
the cylinder-head; figure 15 a cross-section on the plane of line c-c³ figure 11;
figure 16 a cross-section, on an enlarged scale, taken on the plane of line c²-c³
figure 10; and figure 17 a cross-section on line - figure 11. Like letters refer
to like parts in all the figures.
In the accompanying drawings the letter A represents the main shaft of the
engine; B and C, of figures 2, 4, 10, and 11, are the two cylinders of the double
engine which are traversed by the same shaft A, D D are the outer or fixed cylinder-
heads, and EE are the inner or adjustable cylinder-heads. F is a cylinder-shell or
circumferential wall which may be a single shell for two or more such cylinders or
may be a separate shell for each cylinder. Thus figure 8 shews a single cylinder
while figures 2, 4, 10, and 11, represent double cylinders.
For the purpose of giving to each of the cylinders B and C the exact length
required, I propose to make one cylinder-head EE in each adjustable. To this end
one mode of accomplishing the object is represented in figure 4 and shews a disc G

page_text: carried between the cylinder-heads EE and loosely traversed by the shaft A. The
dise G has right and left hand screw-threads on its circumference, as is more clearly
shewn in figure 6, which is a side view of said disc, and these threads engage the
threaded lips a of the cylinder-heads E so that, turning the discs G, the cylinder-
heads will be moved nearer together or farther apart as may be desired. The disc G
may be turned by a wrench or other suitable instrument and has apertures or
projections for receiving such a wrench, as is indicated in figure 6. Another mode of
accomplishing the same result is shewn in figures 14 and 11 in which, between the
said cylinder-head E and the nearest stationary cylinder-head D, is interposed a ring
or disc G¹ which surrounds the shaft A loosely and which has an annular projection j
of a tapering form, that is to say the said projection extends furthest from the face of
the disc G¹ at one part of its circumference and then gradually tapers down so as to
gradually approach the face of said disc G¹, as is indicated by full lines in figure 14
and by dotted lines in figure 11. In this second form the edge of the disc G¹ has
teeth that mesh into a pinion o which can be turned by a handwheel f¹. The
tapering annular projection ; of the disc G¹ extends into a tapering annular recess or
groove in the movable cylinder-head E. It follows that by turning the hand-
wheel and pinion o the disc G' will be turned and with it the tapering annular
projection j, thereby advancing the cylinder-head E gradually, as may from time to
time be necessary. This mechanism for adjusting the cylinder-head is a very simple
construction and in all respects effective and reliable, enabling an ordinary operator
to apply the necessary power to the pinion o without difficulty.
Within each cylinder (B, C,) the shaft A carries an eccentric H which is surrounded
by a ring I. The diameter of this ring is such that at one part of its circumference
it will always contact the inner wall of the cylinder-shell F. The ring I carries an
abutment J which passes into a well 6 through a swivelled block L that has its bearings
in the body of the cylinder. Instead of this swivelled block L the abutment may pass
from the cylinder into the well 6 through a properly contracted opening, as in figure 9,
that fits the abutment between the cylinder and the well b. The ring I within the
cylinder B (or C) is provided with numerous radial apertures, each of which is aligned
with one of a series of channels or flutes d that are formed in the outer edge of the
eccentric H. Figures 5 and 7 are intended to represent these flutes more clearly,
that is to say the outer circumference of the eccentric H has each flute or channel d
in line with one of the openings e of the ring I but each flute is contained between
flanges at the faces of the eccentric, as shewn, so that each opening e is the means of
communication between the inner chamber of the cylinder B (or C) and one of the
fluted chambers d on the exterior of the eccentric H, the flanges and the ridges
between the flutes d fitting the inner circumference of the ring I so nicely as to
practically prevent the escape of steam or other fluid from the Hute chambers;
the flanges and flutes & instead of being formed on the eccentric may be formed
on the ring I and said flanges may be made to lap over part of the sides of the ring or
eccentric if desired. Each cylinder is, near the well into which the abutment J is
adapted to dip, provided with an entrance port g and on the opposite side with a
discharge or exhaust port g². The inlet ports g of the two cylinders B, C, communi-
cate, according to the arrangement shewn in figure 2, with a steam chest M within
which is a double plunger hh connected by a rod i. The two plungers / are at such a
distance from one another that whenever one of the ports g is left open by one of the
plungers the other plunger closes the other port g (see figure 2). A pipe connects
each end of the steam chest M with the corresponding cylinder at a point preferably
opposite to the well b.
but
In order, now, to give a general idea of the operation of this engine, I will state
first that, when two cylinders are used on the same shaft each with an eccentric H
ring I and abutment J, the eccentrics are placed to project in opposite directions from
said shaft, as indicated by dotted lines in figure 1. I will assume that figure 3 shews
the cylinder B in its starting position the inlet port for that cylinder being open that
for the cylinder C being closed, as in figure 2. As the steam or other fluid enters the
cylinder B by the open port g it will begin to act upon the eccentric through the

page_text: ring I and also against what is exposed to its contact of the abutment J and will thus
gradually carry the eccentric with its ring I from the position shewn by full lines in
figure 3 into the position shewn by dotted lines. While the live steam (if steam is
used) thus acts on the eccentric and ring the connection communicates with the
exhaust side of the cylinder but the moment the eccentric with its ring has passed the
opening by attaining the position shewn by dotted lines in figure 3 live steam will
enter through the opening and conduit into one end of the steam chest M. and will
push both plungers h into such a position as to shut the inlet g of the cylinder B and
open that of the cylinder C whereupon the live steam will act in the cylinder C in the
manner already described with reference to cylinder B while in the cylinder B the live
steam will act expansively only. Of course, the opening or conduit I may be placed
wherever desired, to allow a greater or less extent of play for actual pressure of live
steam or a less or greater extent of play for the steam expansively. The
plungers h h are, therefore, of use only in case the steam is to be used expansively.
Thus far, I have merely described the operation of the apparatus without regard to
the apertures e and flutes d; and I here desire to state that said apertures and flutes
are not absolutely necessary to the first part of this invention. As far as the steam
chest M with its plungers his concerned any other steam chest or means of
supplying steam may be used; I do not confine myself to that shewn nor is it always
necessary to use a steam chest. For instance, in figure 8 is shewn a single engine
which will operate successfully with steam, water, or other fluid, without any valve
for regulating the inlet.
The function of the openings e and the operation of the ring I is as follows;
Steam is admitted through the openings é into the chambers d or flutings that
are formed between the ring and eccentric and the columns of steam thus
introduced between the ring and the eccentric will exert nearly the same amount
of pressure against the inner side of the ring which is exerted against the outer
side thereof. Hence, the ring I by this arrangement is nearly balanced on the
eccentric and free to perform its own peculiar motion without undue frictional
contact with the eccentric. I deem it a very important part of this invention to
have provided means for practically balancing this ring on the eccentric, for otherwise
the pressure of the steam against the outer circumference of the ring would produce
considerable friction. But by balancing the ring and getting steam between it
and the eccentric, I obviate these frictional difficulties. At the same time it will be
clear that the steam pressure applied to the abutment assists in causing rotation of the
shaft A. Then again, it will be observed that during the revolution of the shaft the
motion of the eccentric H is entirely different from the motion of the surrounding
ring I. In fact, in this engine it is not necessary nor intended that the eccentrics
shall contact the cylinder-heads excepting perhaps right near the circumference of
the shaft. But suitable collars may be placed on the shaft outside of the cylinder-
heads to keep the eccentrics from touching the cylinder-heads. The ring I which
embraces the eccentric forms the steam-tight joint between the cylinder heads. The
path of this ring, when in motion, of a character very different from that of the
eccentric, as it travels over the face of the cylinder-head, owing to its connection with
the abutment and with the eccentric, in the peculiar motion such as would be used by
a person polishing a plate, and this motion does make the ring polish the cylinder-
heads and keep them flat and straight where the mere motion of a steam-tight eccentric
would be apt to wear depressions in them. The contact surfaces between the cylinder
heads and the ring I should be as free from lateral pressure as possible; and as the
ring I in this engine is practically balanced, as already described, and under very little
pressure, the joined surfaces will not rub together laterally to any objectionable
extent. Thus, the rings I in this engine form the steam or water tight joint and also
carry the abutment; and the abutment in this engine is a 'work-producing element
during the best part of the steam action, because, when fully exposed to steam
pressure, it transmits such pressure by the ring to the eccentric and thus helps to turn
the shaft.

page_text: Instead of admitting steam between the ring and eccentric through apertures in
the ring, it may be admitted by other means which will readily occur to the skilled
mechanic.
The best form of adjustable head is that shewn in figure 11 in which the adjustable
head E is in contact with a disc or ring G¹ interposed between it and the stationary
cylinder-head D. This ring is operated, as previously stated, by means of a hand-
wheel and a pinion o meshing in teeth upon the circumference of the ring G¹. The
cylinder-heads E in each cylinder are adjustable independently of one another. I
have already stated that the block L through which the abutment passes is not
absolutely necessary to the successful operation of this engine; any device which will
hold the ring I so that it cannot revolve with the eccentric and which at the same
time will form the necessary joint and partition will satisfy the same end.
In order to avoid any uneven heating of the engine at the start and an unequal
expansion of parts resulting therefrom, I prefer to surround each cylinder with a
jacket N (see figures 1, 3, and 8,) so as to form a space m on the outer side of the
cylinder into which steam may be introduced, through a pipe n, for pre-heating the
cylinder before starting the engine.
For lubricating the shaft A where it extends beyond each cylinder B, C, (see
figures 10, 11, and 17,) I provide each of said cylinders with a chamber N¹ above the
shaft A, which chamber N¹ is of such size as to carry a considerable quantity of cotton
waste or other fibrous matter N2 in contact with the upper side of said shaft. The
lubricating substance to be used 'can be poured into each chamber N¹ through an
opening in the top thereof, which opening is tightly closed by a plug q. When the
cotton waste, or other fibrous carrier of the lubricant, is thoroughly charged, the
machine is ready to be put in operation. A minute proportion of the steam which is
used in the cylinders communicates with the chambers N₁ through a narrow channel
around the shaft A and presses the air, in said channel and in the chamber N',
against the contents of each chamber N¹ to prevent too rapid withdrawal of the lubri-
cating matter while yet allowing said lubricating matter to go wholly to the shaft and
perform its function. That side of the chamber N¹ which is turned away from the
cylinder B is tightly packed or closed against the escape of air or steam. In other
words, with this invention, I am able to utilize all the lubricating substance that is
applied to the chambers N¹; none will run to waste, none will fail to perform its
function.
I find it desirable to have the main shaft A laterally adjustable, so that, by the
lateral movement of the shaft, the eccentric H and ring I can be adjusted within the
cylinder. For the above purpose, I make the bearings A2 at the sides of the cylinders
and which connect with the boxes N' movable vertically or in any other direction.
This I accomplish by means of adjusting screws a² that pass through threaded lugs b²
on the cylinders (see figure 11) and that come against the bearings A2, as indicated.
The bearings A may be held against the cylinders by screws a³, as shewn. But
the means for adjusting and holding the bearings A² may be varied when desired.
The Invention has reference also to the manner of feeding one of the cylinders with
steam and of causing the steam from one cylinder to feed the other. I have repre-
sented two cylinders B, C, in figures 10 and 11. The cylinder C, which is the main
cylinder of the double engine, may receive its steam direct from an inlet pipe n' and
discharge it through an outlet pipe M¹. The pipe M₁ is the inlet pipe for the next
cylinder B. The cylinder C is the smallest cylinder, in capacity, of the series and
forms a gauge for the quantity of steam which shall pass into the series of cylinders
during each revolution of the shaft. By this means, the cylinder C acts as a valve
for regulating the amount of steam that shall enter the other cylinders. In the
cylinder a valve mechanism may be employed so as to cut off the amount of steam
entering said cylinder when desired to have expansion take place in said cylinder.
When the cylinder C is permitted to be filled with steam, the expansion of the steam
only takes place in the next larger cylinder; but when the valves are used in the
cylinder C and only a certain amount of steam admitted, it is, or may be, permitted to

page_text: expand in said cylinder before reaching the next cylinder. I have represented in the
annexed drawings, one valve mechanism for regulating the admission of steam to the
cylinder and in the said drawings the swivelled block L is made the valve.
Referring to figure 15, the letter g represents the steam inlet, and the letter g' the
steam outlet, for the cylinder. The block L has a recess at R which, after the lower-
most position of the abutment J has been attained, will, as soon as said abutment
inclines its lower end to the right, communicate with the inlet g and with the steam
chamber of the cylinder. The extent of the notch R or recess of the swivel block L
is such that steam is shut off from the steam chamber of the cylinder at the desired
time. The notch R may be made larger or smaller as desired, for the purpose of using
the steam more or less, or not at all, expansively. On the opposite side of the abut-
ment the block L has a recess S which is always in communication with the outlet g².
This valve arrangement, though useful in connection with two cylinders or in any
number of cylinders that may be used in the series, is also in many cases useful in
engines having but a single cylinder; and I do not desire to limit the use of this
valve arrangement to the connection with any particular number of cylinders. But
any other desired valve arrangement may be used to effect the same results.
If the main shaft of a rotary engine is connected directly, by belt or otherwise,
with the pulleys or machinery to be driven, the lateral strain put upon the shaft by
such belt or machinery and the shocks and jars attendant upon running machinery
tend to disarrange the shaft in the cylinders and to cause the shaft to work unevenly.
To overcome these objections and to prevent the shaft and the parts of the engine
connected with the shaft from becoming injured, as above stated, I connect the
shaft A of the engine by means of a yielding, yet positive, connection with a separate
shaft Y. This latter shaft Y is to be connected with the machinery or other object to
be actuated. One method for carrying out this part of the invention is illustrated in
the accompanying drawings, wherein Y is the shaft to be driven by the main engine
shaft, the shafts A and Y being shewn aligned. Each of these shafts A, Y, as shewn,
carries a rigidly attached disc, the shaft A having the disc and the shaft Y the
disc S, which discs are of about the same diameter and near to one another as shewn.
One of these discs, say the disc s, has one or more notches 2 in its circumference and
in each of these notches is placed a block u and rubber or other cushions t¹, as in
figure 16, the block being between the cushions and the cushions in contact with the
edges of the recess in the disc. A belt V connects the opposite disc with the block u
so that, as the shaft A is turned it communicates motion to the fly-wheel shaft Y through
one of the intervening cushions &¹ that are between each block u and the wall of the
notched disc s. Now, if the shaft Y is moved slightly laterally, by the pressure exerted
through the belt it drives, or if it receives a sudden jar or other injurious motion, such
movements will not affect the shaft A because of the yielding connection between the
shafts A and Y. But it is evident that the details of construction above set forth
may be changed, for making a yielding connection between the driving and driven
shafts.
?'
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The combination of the cylinder B shaft A and eccentric H on said shaft with
the ring I loosely placed around said eccentric and with the abutment J carried by
said ring, substantially as specified.
2. The combination, in a rotary engine, of the cylinder B having well b with the
shaft A cccentric H ring I around said eccentric and abutment J carried by said ring
and entering said well, substantially as specified.
3. In a rotary engine, the combination of the fixed cylinder-head D with the
adjustable cylinder head E intermediate eccentric H and ring I surrounding said
eccentric and carrying the abutment J, all arranged so that the ring 1 during its
motion shall contact the cylinder-heads as specified.
4. In a rotary engine, the combination of two cylinders B, C, with the shaft A

page_text: eccentrics H rings I having abutments J steam conduits 1 and steam chest: M
having the movable plungers or valves h, all arranged for joint operation, as
specified.
5. In a rotary engine, the cylinder B surrounded by steam jacket N for the
purpose of heating the parts before starting the engine, as specified.
6. In a rotary engine, the eccentric H on the main shaft combined with the sur-
rounding ring and with means, substantially as described, for admitting steam between
said ring and said eccentric, as specified.
7. In a rotary engine, the eccentric H combined with the shaft A to be driven
with the cylinder B and with the surrounding ring 1 having abutment J the ring
being perforated to admit steam between the eccentric and the ring, as specified.
8. The eccentric H having flutes or chambers d and flanges f combined with the
surrounding ring I having apertures e aligned with the chambers d respectively and
with the surrounding cylinder B, as specified.
9. In a rotary engine, the balanced ring I and abutment J placed around!
an eccentric of the shaft A and within the cylinder B, all arranged so that the
working power of the steam or other fluid admitted to the engine shall be exerted
upon said eccentric through said balanced ring and abutment as specified.
10. The combination of the fixed cylinder head D with the movable cylinder-head E
having annular tapering groove 2 and with the interposed ring G' having annular
tapering projection j entering said groove and with means, substantially as described,
for revolving the disc G¹, as specified.
11. The combination of the shaft A and steam cylinder B with the chamber N¹
annexed to said cylinder and in communication with the steam chamber thereof, said
chamber N' having the plug q all arranged to maintain within said chamber N¹ a
quantity of lubricating matter in contact with the shaft A and with the steam, as
specified.
12. In a rotary engine, the driving shaft A combined with the driven shaft Y and
with a yielding connection between said shafts, substantially as described.
13. The combination of the driving shaft A of a rotary engine and its disc with
the driving shaft Y its notched discs and with the block u connected with the disc r
and cushions t¹, said cushions and block being located within the notches of the discs,
substantially as described.
14. In a rotary engine, the cylinder B combined with the cylinder C and with a
connection from the exhaust of one cylinder to the inlet of the other, one cylinder
acting as a cut-off or valve to regulate the admission of steam to the other cylinder,
substantially as described.
15. The combination in a rotary engine of the abutment J and its swivel block L
with the steam inlet g and steam outlet g², the swivel block L having the recessed
portions R and S to become thereby a combined valve and guide for the abutment,
substantially as herein shewn and described.
16. In a rotary engine, the cylinder B and shaft A combined with the movable
bearing A² carried by said cylinder and with means, substantially as described, for
adjusting and holding said cylinder, substantially as specified.
Dated this 7th day of January 1000.
Dated this day of Januar
A. MELVILLE CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.
A. MELVILLE CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.