Improvements in Rotary Engines, Pumps, or like Machines.
Year: 1892

page_text: Date of Application, 26th July, 1892-Accepted, 3rd Dec., 1892
COMPLETE SPECIFICATION.
Improvements in Rotary Engines, Pumps, or like Machines.
I, EDWARD WALDRON, of 3733 Walnut Street, Philadelphia, in the County of
Philadelphia, State of Pennsylvania, United States of America, Engineer, do
ereby declare the nature of my invention, and in what manner the same is to
e performed to be particularly described and ascertained in and by the following
tatements:-
The invention is applicable both for transmitting and receiving power, and may
be used not only as an engine or pump but also for compressing or exhausting air
or gas and for measuring liquids.
The invention set out in this application is an improvement upon the rotary
engine, pump or motor disclosed in my Letters Patent No. 1511 of 1878, dated
April 16th, 1878.'
More particularly, the invention relates to improved details of construction with
the object in view of making the engine more durable, reliable and efficient.
Referring to the drawings:
-
Fig. 1 is à sectional plan view of my improved rotary engine, pump or motor on
line of Fig. 2 with two of the pistons shown in an horizontal position.
Fig. 2 is a cross section of same on line y y of Fig. 1 drawn to a smaller scale
showing the pistons in section.
Fig. 3 is a perspective view of a number of the details of the connecting parts
between the cylinder drum and shaft.
The parts are shown separated, and are also drawn to a reduced scale.
Fig. 1 is a plan view of my improved rotary engine;
Fig. 5 is a sectional clevation of same on line 2 2 of Fig. 2.
Fig. 6 is a perspective view of one of the pistons ;
Fig. 7 is a perspective view of the cylinder drum;
Fig. 8 is an end elevation of one of the packing rings for the shaft and
cylinder, and
Fig. 9 is an enlarged view of a portion of Fig. 1.
For the sake of clearness in describing the construction of my engine, pump or
motor I shall speak of it more particularly as a steam engine.
A is the cylinder and is provided at each cud with heads A¹ having orifices
through which the piston shafts extend. The central portions of the cylinder
comprising the parts T T are concentric with one another, and the parts TT* are
eccentric with reference to a central line through the shafts located at each end,
and the end portions adjacent to the heads A¹ are enlarged, and are circular, and
concentric with the shafts. The heads A' carry the journals a for the shafts fas
shown in Figs. 4 and 5, and the central or middle part of the cylinder A is formed
with the steam inlet port M and exhaust ports an opening into the exhaust outlet N.
These exhaust ports n n converge from the lateral sides of the cylinder toward the
middle and unite in the outlet N (see Figs. 4 and 5). The object of this convergence
is to enable the pistons to sweep the ports in such a manner that the said ports in
effect travel laterally over the pistons as they advance, and all water of condensa-
The interior of the cylinder
tion is rapidly ejected with a minimum of resistance.
is made up of four surfaces, to wit; the concentric surfaces T T arranged
diametrically opposite and differing in radius a distance equal to the throw of the
pistons in their races of the drum B rotating within said cylinder, and the
surfaces T T which are eccentric or cam shaped and contain respectively the steam
The surfaces T T' connect with the concentric
inlet port M and exhaust ports n n.
surfaces T T so as to form a continuous internal surface for the outer edges of the
pistons. An important feature is that the exhaust ports n n extend down somewhat

page_text: into the concentric surface T and likewise the steam port M is shortened a corre-
sponding distance so as to recede upon the surface T slightly, or the surface T may be
continued a corresponding distance toward the steam port M. By examining Fig. 2
it will be observed that the two left hand pistons b are just upon the ports M and n,
that is, one piston is leaving the port n (see dotted lines) and the other piston is
moving on to port M. While those pistons are in those positions, the other two
pistons on the right are not in corresponding positions with the other ends of the
ports but the upper piston is beyond the end of the exhaust port n, and the lower
piston is just beyond the end of the port M. It is necessary for the two pistons of
any pair to be separated a distance equal to the distance between the edges of the
parts Mn, otherwise there would be a free escape of steam without a resulting
development of power. The object of this arrangement of ports and surface T is to
enable the piston b which is approaching the exhaust ports n to remain stationary
so far as radial movement is concerned until it has passed beyond the end of the
exhaust port so as to relieve the pressure back of it and thus reduce the friction of
its radial movement. As soon as it has passed on sufficiently to enable the relief of
the pressure at its back it meets the eccentric surface T2 and cominences to be
pushed inward. In this manner its. inward movement is not performed against a
strong lateral pressure and hence all excessive wear of the piston in its races is
overcome.
Another important feature of this improvement is that when the pistons come in
line with the beginning of the exhaust ports n, the steam and water back of the
pistons may be relieved by blowing up through the grooves on the ends of the
pistons, through the grooves S in the cylinder, and in front of the pistons, and out
by the exhaust ports n before the steam back of the piston has been exhausted.
This is important since it removes at once the great resistance to the pistons being
pushed in by the eccentric portion T2 of the cylinder. This relief is a great
advantage, for the pistons move so rapidly that it is essential to avoid all clogging
or obstruction of their free reciprocation. The relief of the water and steam from
under the pistons in this manner before the main exhaust from back of the pistons
has the advantage of relief into a space when there is the least pressure and
hence the least resistance, to relief. In the case of the piston passing over the
steam port M the steam exists with the initial pressure upon both sides and
consequently its outward movement is not attended with any excessive lateral
friction. The moving back of the steam port M is only to correspond to the moving
back of the exhaust port n as the edges of these ports must be separated a distance
not less than 90 degrees.
The pistons are made as shown in Fig. 6 and work in the races in the drum B
and the races in the packing rings C (see Figs. 2 and 3). They are recessed on
the sides as at t to reduce the weight and also the friction in the races and also the
consequent outward tendency due to centrifugal action. By reducing the weight
and centrifugal tendency 1 reduce the pressure of the pistons against the interior
walls of the cylinder and thus very materially reduce the amount of friction between
the said pistons and cylinder. These pistons are arranged in pairs situated on
diametrically opposite sides of the drum B, and pressed outward by spring distance
rods G consisting of tubes G¹ open at one end and fitted with a movable head G'
and a spring within to push said head outward. By this means the pistous are
kept normally a distance apart and the springs admit of adjustment for any
variations in the internal diameters of the cylinder. The distance rods work
through holes G³ which they snugly fit, and there are preferably two of such
distance pieces for each pair of pistons as shown in Fig. 1.
Each end of the drum B preferably slightly enlarged as at B2 and is fitted to the
several parts shown in Fig. 3 (which are separated for clearness) to wit, parts C, D, E
and F. The drum is received in and fits the recess D' and is bolted to said head D
and the head of the shaft f by bolts V. (Fig. 1). Fitting over the head D with
a steam tight joint and having freedom of lateral movement is the packing ring C,
and this ring is pressed forward against the face (Fig. 1) of the cylinder by

page_text: springs E' extending into recesses d'in its rear and held in place by lugs e of the
ring E bolted to the outside of the head D.
By removing the head A' the shaft f, and the head D the pistons may be drawn
out without withdrawing the drum B. This is important. The ring is clearly
shown in Fig. 3 and consists of an annular body portion formed with a narrow rim
for contact with the surface i, and also at four equi-distant places with wedge shaped
pieces H having races for the pistons b. The outer ends of these races are
slotted at 2 and these slots leading into recesses (Figs. 1 and 3). The object of
this is to supply steam to the running surfaces and insure thorough lubrication and
thereby reduce the friction and wear, and also to act as pockets for the collection of
any dirt &c.
By making the pieces H wedge shaped 1 am enabled to fit them to the recesses d
in the head D (Fig. 3) and thus form a steam tight joint and yet permit them to
move parallel with the length of the cylinder in said recesses, and I also maintain
the advantageous construction of proportioning the surface to the friction between
the parts which is proportional to the distance travelled, that is to say, that, as we
move away from the axis of rotation of the drum and shafts of the engine, the metal
surface of the parts H exposed to contact with the cylinder surface i gradually
increases and this increase is substantially proportional to increase of distance
travelled.
It will now be seen that the drum at each end of the cylinder A is packed by
the rings C and is supported in bearings by the shafts.
3
This construction has the further advantage of being perfectly self lubricating
since the outer parts of the pieces H are lubricated by the steam and water outside
of the annular rim c; the annular rim e is lubricated by the steam and water passing
into the slot 2 (Fig. 1); and the inner ports of the pieces H are lubricated by
the steam and water passing into the race h.
The enlarged ends B2 of the drum B receive the inner ends of the wedge
shaped pieces, and as the faces of these pieces wear in working over the surfaces i
of the cylinder, they may shift over the enlarged parts B of the drum, and
compensate for wear without the least possibility of binding. This construction
is shown in Fig. 1, Fig. 2 and Fig. 9.
1 pack the shafts when they pass through the cylinder heads A and make
the sleeves slide upon the inner edges of the opening in the heads as is clearly
shown in Fig. 1 at j. The shaft has an enlarged portion" adjacent to the
head F, and over the enlarged portion the sleeve J fits and is pressed outward
by springs L. The sleeve has a packing gland J₁ which is screwed in upon the
shaft against a packing, or if desired it might be screwed into the sleeve. The
inner flange of the sleeve is notched as at k (Figs. 1 and 8) and through these
notches are placed screws which are held by the head F and they perform the
dual duty of making the sleeve rotate with the shaft and hold it to the shaft
when the head A' is removed. By this construction the packing around the shaft
and between it and the sleeve may be always maintained steam tight and all
leakages instantly stopped so that no steam can escape by way of the shaft.
Furthermore the construction is one which insures all the wear coming upon the
removable head A' which can readily be removed for repairing or for permitting
access to the packing ring or sleeve for repairs or other necessary purposes.
Furthermore it is possible to remove the head A' for adjusting or obtaining access
to the annular ring C and its connections without dismantling the other parts as
Furthermore in
was necessary in the case of my Patent hereinbefore referred to.
this case all of the wear comes upon a part which is inexpensive to replace,
whereas in my former Patent the wear came upon one of the heads of the drum
which was expensive to replace.
Returning to the packing ring C, I would direct attention to the fact that the
wedge pieces H project inwardly and are received in corresponding notches d in
the head D and thereby insure the ring C rotating with the drum B and pistons.
It is true that the pistons of themselves would cause the ring to rotate but their

page_text: action wouki De uneven and woum promice a strong fiction on the piston
it is desired to remove.
By the construction shown the head D primarily causes the ring to rotate with
the drum and pistons, and relieves the pistons of any duty other than rotating the
drum and its shafts. The action of the pistons on the pieces H is to rotate
the ring C and drum as an unit but without any backward strain on the outer
edge of the pistons.
Holes P extend entirely through the drum-heads D and F into the spaces or
chambers at each end of the engines so as to equalize the pressure on the outside
of the packing rings C. See Figs. 1, 2, 3, 5 and 7.
On each end of the cylinder and along the extreme edges of the surfaces T² T²
are grooves S (hereinbefore referred to) which grooves in length correspond to the
ports M and nn (Figs. 2 and 5). To work in conjunction with these grooves are
grooves s in the ends of the pistons as shown in Figs. 1 and 6. The object of
these grooves is to supply steam on one hand when passing the steam port M and
allow of the escape of steam and water when passing the exhaust ports n and when
the pistons are entering the drum as before explained. The steam passes into
grooves S at the bottom of the engine, and then through grooves s on the ends of
the pistons, beneath the pistons and filling the bottoms of the races b' and insuring
the pistons being kept positively to the interior surface of cylinder, preventing all
shattering and necessity for heavy springs in the distance rods.
Once the piston
passes the end of the port M the grooves s are sealed and the steam back of the
piston remains locked in. When the piston reaches the exhaust port n the upper
grooves S are met and the steam and water is relieved, and the inward movement
of the piston positively ejects the steam and water of condensation against the small
resistance of the exhaust steam, and the piston sweeps it through the exhaust ports.
Its release at the upper port is also important because the piston must be pushed
into the drum and all resistance to such action must be removed. These grooves S
also insure the steam for lubricating purposes passing to the slots 2 in the rings C,
and also to the space between the rings and heads D.
An examination of Fig. I will show that the inner ends of the piston races are
enlarged at L by longitudinal grooves. While there is a limited space between the
walls of the race and the distance rods G for the passage of steam and water when
the pistons reciprocate, yet it is not sufficient when the engine is running at its
normal speed, and for this reason the grooves L' are employed as they form
channels for the ready escape of the steam and water of condensation to either end
of the drum and to the grooves s in the ends of the pistons.
The water of condensation from the steam port passes off by pipe M' and from
the exhaust port by drip pipe O.
The pistons rotate in the direction of the arrows, and during their rotation about
the axis of the drum, they reciprocate in pairs, and as the diameter of the
cylinder is substantially the same for all lines taken through the said axis of the
drum and shafts of the engine, one piston recedes with substantially the same
velocity as the one diametrically opposite is projected.
While I prefer the construction shown 1 do not confine myself to the exact
details as they may be modified without departing from my invention.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1st. In a rotary engine or pump the combination of a cylinder formed with shaft
bearings at each end, a rotary drum and pistons of a length equal to the length of
the cylinder, a packing between the ends of the drum and cylinder, a shaft at each
end supported in said bearings and having a flanged head bolted to the respective
ends of the drum and supporting it, cylinder heads for each end of the cylinder,
and a rotatable steam or water tight packing encircling the shafts between their
heads and the respective cylinder beads through which the shafts extend.

page_text: 2nd. In a rotary engine or pump, a cylinder having its inner surface formed
oncentric and eccentric parts arranged alternately about the axis of rotation of
he shaft, and inlet and exhaust ports arranged diametrically opposite and of different
engths in which the exhaust port occupies a space more than ninety degrees, in
combination with a rotary shaft and pistons carried with the shaft sweeping the
nterior face of the cylinder.
3rd. In a rotary engine or pump, a cylinder having two oppositely arranged
concentric parts TT of different radii and two opposite cam or eccentric parts TT
connecting said concentric parts and respectively provided with inlet and exhaust
ports in which the exhaust port consists of two oblique ports substantially covering
the width of the cylinder, in combination with travelling pistons moving about a
fixed axis and sweeping the interior surface of the cylinder.
4th. In a rotary engine or pump, the combination of a cylinder having concentric
and eccentric parts substantially as set out and provided with inlet and exhaust
ports arranged in the eccentric parts diametrically opposite and in which the
adjacent edges of the two ports are separated a distance corresponding to ninety
degrees and in which the exhaust port is of greater length than the inlet port, with
a rotary drum arranged within the cylinder, and rotary movable pistons arranged
diametrically in pairs and movable in races formed in the drum.
5th. In a rotary engine or pump, the cylinder having an interior surface formed
of concentric and eccentric shaped parts arranged alternately, in combination with
a drum provided with piston races arranged within said cylinder and of substantially
equal length with the cylinder, pistons for said drum, removable heads for the ends
of said drum to hold the pistons against longitudinal movement, and two shafts
arranged one at each end and bolted to the drum, whereby the shaft at one end
can be removed and the pistons withdrawn without removing the drum.
6th. lu a rotary engine or pump, the cylinder having interior concentric and
eccentric shaped surfaces arranged alternately about the interior circumference
and parallel end surfaces, in combination with a rotary drum and reciprocating
pistons, a head bolted to each end of the drum, having radial slots and packing
rings carried by said heads having piston guide pieces fitting said slots and movable
to and from the end surfaces of the cylinder.
7th. In a rotary engine, the cylinder having interior concentric and eccentric
shaped surfaces arranged alternately about the interior circumference and parallel
end surfaces, in combination with a rotary drum and reciprocating pistons, a head
bolted to each end of the drum having radial slots, and packing rings carried by
said heads having piston guide pieces fitting said slots and movable to and from the
end surfaces of the cylinder and springs supported by the heads to force said rings
against the end surfaces.
8th. In a rotary engine or pump, the cylinder having interior concentric and
eccentric shaped surfaces arranged alternately about the interior circumference
and parallel end surfaces, in combination with a rotary drum and reciprocating
pistons, a head bolted to each end of the drum having radial slots, and packing
rings carried by said heads having piston guide pieces fitting said slots and movable
to and from the end surfaces of the cylinder, the said rings being formed with a
thin annular contact rim having a lubricating groove and recess leading from the
interior of the cylinder to its contact surface.
9th. In a rotary engine or pump, a cylinder having its inner surface formed of
concentric and eccentric parts arranged alternately about the axis of rotation of the
shaft, and inlet and exhaust ports arranged diametrically opposite, in which the
exhaust port extends over a space of more than ninety degrees, in combination with
a rotary shaft and pistons carried with the shaft and sweeping the interior face of
the cylinder.
10th. In a rotary engine or pump, the combination of the cylinder having heads
5 at each end, a rotary drum and pistons within the cylinder, a shaft projecting from
the drum through the head, a stuffing box or sleeve surrounding the shaft, a
packing between the shaft and said box or sleeve, and springs to press the box or

page_text: sleeve against the interior surface of the head and make a steam and water tight
rotary joint.
11th. In a rotary engine or pump, the combination of the cylinder having heads
at each end, a rotary drum and pistons within the cylinder, a shaft projecting from
the drum through the head, a box or sleeve carried with the rotating shaft and
forming a steam and water tight joint between the shaft and cylinder head.
12th. In a rotary engine or pump, the combination of the cylinder having an
interior made of concentric and eccentric parts, with a rotary drum located therein
and formed with radial races for the pistons provided with enlargements or channels
at the bottom entirely across the drum for the ready escape of water and steam
from under the pistons when moving inwardly to the ends of the drum, and pistons
movably supported in said races.
13th. In a rotary engine or pump, a cylinder having an interior made of concentric
and eccentric shaped parts and parallel end surfaces, in combination with a rotary
drum of greater length than the interior surface of the cylinder and of greater
diameter on its ends than at the middle and formed with radial piston races, heads
for said drum, pistons working on the races of said drum, and a packing or skeleton
ring encircling said heads of the drum and formed with guide or race pieces for
the pistons extending inward toward the enlarged diameters of the drum, and
movable longitudinally to make a tight joint with the end surfaces of the cylinder.
14th. In a rotary engine or pump, the cylinder having concentric and eccentric
shaped interior surface as shown, and parallel end surfaces, in combination with a
rotary drum, pistons and heads therefor, and encircling packing rings for said heads,
an irregular contact surface for making a steam and water tight joint with the
end surfaces and allowing of ample lubrication, said surface consisting of a narrow
annular rim and guide pieces for the pistons said guide pieces projecting beyond
the annular rim and formed with steam or water spaces extending beyond the
said rim.
15th. In a rotary engine or pump, the cylinder formed of concentric and
eccentric parts arranged alternately in combination with a rotary drum having
radial races, and radially reciprocating pistons having their inner edge and ends
made of the thickness of the race and formed with its two side walls greatly
reduced so as to reduce the thickness of the metal as we approach from the outer
edge to the inner edge of the said pistons substantially as shown and for the
purpose set out.
16th. In a rotary engine, a cylinder having its inner surface formed of concentric
and eccentric parts arranged alternately about the axis of rotation of the shaft,
and steam inlet and exhaust ports arranged diametrically opposite, in which the
exhaust port extends over a space of more than ninety degrees and the steam port
a space of less than ninety degrees, in combination with a rotary shaft and four
pistons arranged at angles of ninety degrees and carried with the shaft and sweeping
the interior face of the cylinder, whereby two spaces between the pistons may be
exhausting while only one is receiving steam or water and the pistons over the
exhaust are relieved before moving on the eccentric part of the cylinder.
17th. In a rotary engine or pump, a cylinder having its interior composed of
alternate concentric and eccentric parts and in which the concentric parts are
alternately of different diameters, an inlet port arranged in one of the eccentric
parts and an exhaust port arranged in the alternate eccentric part and being of a
length equal to that of the eccentric part and part of the concentric part; in
combination with a rotating drum having its axis arranged concentric with the
concentric parts of the cylinder and provided with piston races and reciprocating
pistons carried by the drum and adapted to sweep the interior of the cylinder; the
whole operating to exhaust the steam or water from back of the pistons before
the said pistons reach the eccentric portion of the cylinder, and thereby reduce the
friction and wear upon the engine or pump and allowing a higher speed to be
attained.
18th. A rotary engine or pump having a cylinder the interior of which is formed

page_text: of concentric and cam or eccentric portions arranged alternately, one of the
alternate cams or eccentric portions being provided with exhaust ports and the
remaining cam or eccentric portions being provided with inlet ports and in which
the exhaust ports are of greater length than the inlet ports and in which the
cylinder and rotating drum having radially movable pistons is arranged to rotate.
19th. In a rotary engine or pump, a cylinder having its interior surface made of
concentric and cam shaped or eccentric parts and provided with a rotary drum
having radially movable pistons in which the opposite pistons are kept apart by
distance rods formed of sliding tubes and internal springs.
20th. A rotary engine or pump having a rotary drum working inside of a
cylinder provided with piston races in which are arranged reciprocated pistons
formed with their faces recessed near their inner or lower parts to reduce the
centrifugal action, and having the outer edges and bottom of large thickness where
the strain and wear comes upon them.
3003
Dated this on day of the
EDWARD WALDRON.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.