Improvements in and relating to Alternating-piston Rotary Engines, for Steam, Air, Gas or any other Motive Agency.
Year: 1898

page_text: Date of Application, 21st June, 1898-Accepted, 10th Sept., 1898
Improvements in and relating to Alternating-piston Rotary Engines,
for Steam, Air, Gas or any other Motive Agency.
I, JOIN HANDY PARSONS, a Citizen of the United States of America, residing
at 717, Monroe Street, in the City of Wilmington, County of Newcastle and State
of Delaware, United States of America, Locomotive and Mechanical Engineer, do
hereby declare the nature of this invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement:
My invention refers to alternating-piston rotary engines, for steam, air, gas,
or any other motive agency, and consists of certain improvements to be hereinafter
described; the object of the invention being to provide a mechanism possessing
superior efficiency and capability for use; and the invention therefore consists
essentially in the construction, arrangement and combination of parts, substan-
tially as will be hereinafter described and claimed.
In the accompanying drawings illustrating my invention-
Figure 1 is a horizontal sectional plan view of a rotary engine constructed in
accordance with my invention.
Figure 2 is a longitudinal, vertical, sectional view of the same.
Figure 3 is an end elevation, showing the mechanical devices for regulating the
size of the steam-inlet opening.
Figure 4 is an end elevation, the cylinder head being removed to show the
pistons.
Figure 5 is a detail view, showing the wheel or disc on the drive-shaft, and the
links pivoted thereto, certain parts being shown in section.
Figure 6 is an elevational view of a duplicate construction of my improved
rotary engine arranged as a compound engine.
Figure 7 is a similar elevational view of a duplicate construction of my rotary
engine, arranged as a duplex engine.
Figure 8 is an end elevation of my engine, showing in section one form of
reversing valve mechanism.
Figure 9 is an inclined section on the line x of Figure 8.
Figure 10 is a transverse section on the line y-y of Figure 8.
Figure 11 is a transverse section on the line of Figure 8.
Figure 12 is an end elevation of my improved engine represented as equipped
with a different style of reversing gear, which is shown in detail.
Figure 13 is a cross-section illustrating the parts of said reversing gear.
Figure 14 is an end elevation with the cylinder head removed to show the
pistons, certain parts of the reversing device being indicated in dotted lines.
Figure 15 is an end elevation of my improved engine, showing the means
belonging to the said reversing mechanism for graduating the size of the steam-
inlet opening.
Figure 16 is an end elevation, partly in section, of a modified form of my
improved rotary engine, 'the cylinder head being removed to show the pistons
and other construction.

page_text: Figure 17 is a side elevation of the same.
Figure 18 is an end elevation of a further modified form of my improved engine.
Figure 19 is a side elevation of the same.
Similar numerals of reference designate corresponding parts throughout all
the different figures of the drawing.
1 denotes the cylinder, having the integral head 2, and the removable head 3,
said cylinder being cast integral with a supporting base or frame 6, which may
obviously be of any desired shape and pattern.
The inner head 2 is provided with a boss 5, through which passes a shaft con-
sisting of the rectilineal sections 8, 9, and 10, having different diameters for a
purpose to be hereinafter explained That section of the shaft that lies within
the boss 5 is designated by the reference numeral 8, and it is surrounded by a
sleeve 11, which is rotatable upon and independent of the shaft section 8, and
which is supported within a surrounding sleeve of brass, Babbitt metal, or other
suitable bearing material, as shown. On the shaft section 10 is another sleeve 13.
This sleeve 13 is rotatable upon the shaft section 10. A hub 12, on shaft 8, is
secured to or formed integral with the sleeve 11; and both sleeve 13 and hub 12
are formed integral with the piston 14. The shaft section 9, above-mentioned,
intervenes immediately between the shaft-sections 8 and 10, and on this section 9
is a hub 16 of another piston 15, said hub being fast on section 9. Thus it will
be seen that one piston practically interlocks with the other, and applies its
power to the actuated shaft at a point between the two points where the other
piston applies its motive power thereto. Within the sleeve 13, is another sleeve 17,
which is directly around shaft section 10, and sleeve 13 also rotates within a
Babbitt metal or brass bearing 18. In the head 3 of cylinder 1 is a central recess
or hollow enlargement 7 that receives the bearing sleeve 18 and also shaft sec-
tion 10, sleeve 17, and sleeve or hub 13. Also in the outer end of recess 7 is a
disc or washer 19 that is pressed against the end of the shaft 10 by means of a
spring 20, the object of this being to keep the shaft in proper position endwise.
The pistons 14 and 15 have the general wedge shape common to pistons of
engines of this type, and for the sake of lightness they may be made hollow, as
shown in Figures 1 and 2, but when so made the interior cavities are closed to
the entrance thereinto of the steam. These pistons are formed with peripheral
grooves and side grooves to receive suitable packing strips. In Figures 4 and 14
I have shown pistons 14 and 15, having side packing strips 70 which form a
tight joint between the pistons and the heads 2 and 3 of the cylinder 1, and the
sides of the pistons are preferably cut away so as to leave a small space between
them and the cylinder heads, the spaces on the two sides communicating with each
other through a port 35 running through a solid part of the piston, and thus
steam can pass from one side of the piston to the other, so as to give it a lateral
balance, as it were, and prevent it from being pressed against the one head or
the other. The peripheries of the pistons may also be cut away if desired, in like
manner as are the sides. 21, 22, and 23 denote small packing pieces held in
position by springs or spring pins, as shown, and used to make a steam tight
joint between the parts.
The driving shaft 30, eccentric to the cylinder 1 and shaft 8, 9, 10, is journaled
in a bearing 50, formed or arranged on the main frame 6 in any desired or suit-
able manner, see Figures 1 and 2. Secured to this shaft is a wheel or disc 31
provided at diametrically opposite points with wrist pins 32, 32, to which are
pivotally connected links 71 and 72, the opposite ends of which are secured to
crank arms 33 and 34, fastened respectively to the piston sleeve 11 and the shaft 8.
Located upon one side of cylinder 1 as well as partially beneath the same, is
the exhaust chamber 24, having suitable ports 25 that communicate with the
interior of cylinder 1, as shown in Figures 1 and 2. The exhaust pipe 26 leads
from the exhaust chamber 24. Located upon the opposite side of cylinder 1, is
the live steam chamber 27, entered by the steam supply pipe 29, and communicat-
ing through ports 28 with the interior of chamber 73 formed in the cylinder

page_text: head 3, said chamber having a removable outer cover plate 4, and said chamber 73,
as shown in Figures 1 and 3, communicates with the interior of cylinder 1 through
an elongated arc-shaped opening that is covered and controlled by a segment
plate 36, movable for the purpose of graduating the size of the said opening and
admitting more or less steam into the cylinder, accordingly as it may be needed.
The segment plate 36 is provided with a rack bar 37 engaged by a pinion 38 on
a shaft 39 that is supported in a bearing in the cover plate 4, see Figure 1, through
which plate said shaft projects and is provided on its outer end with a square
head for the application of a wrench; or a lever handle may be arranged to
operate it, or it may be controlled by automatic means.
In that form of the engine shown in Figures 1 and 2, I have illustrated no
reversing mechanism, but in Figures 8, 9, 10 and 11 I show a construction and
arrangement of parts whereby a reversal of the engine may be accomplished when
desired, the engine proper shown in the latter figures being practically the same
as that in Figures 1 and 2 except as to the ingress and egress of steam from the
cylinder.
In the Figures 8, 9, 10 and 11, of which we are now speaking, 40 denotes
a chamber in the base of the engine frame, on the outside of the cylinder head, which
chamber receives live steam from the boiler under full pressure. Above this
chamber is a valve-chamber 41, containing a slide valve 42, preferably of a segmen-
tal or curved form corresponding to the shape of chamber 41, said valve being
shiftable by means of a pivoted lever 4:3 that connects with valve 42 by a rod 44.
The valve 42 has ports 46, 46, and a lateral recess 47. In the cylinder head are
ports 48, 48, and alongside of chamber 40 are the exhaust or outlet passages 49, 49.
When the valve 42 is in the position shown in Figure 8, steam can pass from
chamber 40 through port 45, then through the recess 47 and one of the ports 48,
into the cylinder 1, see Figure 11, while at the same time the exhaust is emerging
from the cylinder through the other one of ports 48, one of ports 46, and exhaust 49,
see Figures 9 and 10. When the valve 42 is shifted in position the inlet port
will become the outlet, and the outlet the inlet.
In Figure 6 there is illustrated a compound engine, consisting of two engines A
and A', of my improved alternating-piston type, the same being arranged so that
they will both actuate the same shaft, which has thereon the balance wheel 5.1
and pulley 52, it being noted that the passage 53 conveys the exhaust steam from
engine A to engine A. In Figure 7 I have shown a duplex engine consisting
of two of my engines 13 and B. These two are arranged, of course, to impart their
actuating impulse to the same shaft, as in the case with the compound engine of
Figure 6.
In Figures 12, 13, 14 and 15, I have represented an improved form of reversing
mechanism, which I will now proceed to explain in detail. In the bead 75 of the
cylinder is a chamber 76 containing the live steam at boiler pressure, from which
the steam is admitted to the cylinder through one or the other of two points in
an inlet opening, which is shown at 77, Figure 15, and which is covered by valve
plates 78 and 79, which can be moved so as to cover or uncover more or less of
the said steam inlet 77, as may be desired. Steam inlet 77 is a circular opening,
in which the segment plate 78 is movable, the segment plate 79 being likewise
movable or adjustable over the opening 77 and over part of plate 78, as shown
in Figure 15. Un plate 78 is a rack 80, and attached to plate 79 is a rack 81,
the rack 80 being engaged by a pinion 65, and the rack 81 by a pinion 64. The
pinion 65 is rigid on the end of a horizontal shaft 54, and the pinion 64 is rigid
on the end of a horizontal sleeve 63, through which sleeve the shaft 54 passes,
said shaft and sleeve being supported in a bearing 82 in the front plate 83 of
the steam chamber 76. On the shaft 54 outside the chamber 76 is rigidly
fastened an arm 59, and alongside of it is another similar arm 58, which is
securely fastened to the sleeve 63, said arms projecting upwardly and normally
at an angle to each other. The arm 59 has a short horizontal projection 84, and
the arm 58 a short projection 85, while projecting from the cover 83 or some

page_text: other part of the machine are a couple of rigid pins 86, in horizontal line with
each other, and serving as stops for the arms 58 and 59, limiting the movement
of said arms towards each other, it being further remarked that the arms are
provided with springs which normally draw them against the stops 86, as shown
in Figure 12. Supported pivotally on the outer end of the shaft 54 is a lever 56,
which is kept upon the shaft by the end nut 87. Lever 56 has a catch 66 adapted
to engage the notched sector 57 and thus hold the lever in any desired position.
Lever 50 also has a downwardly-extending arm 55, whose lower end carries a pin
that rides in the irregular groove of the curved lever 53, which is pivoted at 60,
and which has a short projecting arm 61, bifurcated or forked at the end and
Joosely enclosing the free end of a lever 62 that is fastened to a pin 88, journaled
within the base of the engine frame below the cylinder and rigidly attached to
a curved plate 89, which oscillates when the lever 62 is vibrated. The plate or
bar 89 is loosely connected near each end with central pins 90 fixed in the
plates 91, 91, and hence the result of oscillating the bar 89 is to laterally shitt
the plates 91, 91, Figure 14, in a horizontal but in opposite directions, the move-
ment taking place in certain ways or guides provided for them, and they serving
as covers for the exhaust ports 92, 92, so that when the exhaust ports on one side
of the cylinder are opened the others on the opposite side will be closed. The
operation of this reversing mechanism will be readily perceived. The lever 56
is shown in Figure 12 in its central position. When it is moved towards the right,
for instance, it will oscillate the lever arm 59, thus rotating pinion 65 and causing
the plate 78 to be moved relatively to the steam-inlet port 77, opening said port
at a certain point so as to allow the steam to enter at that point into the cylinder;
and while this opening of the steam port is being performed by the gearing
arrangement which have described, the grooved lever 53 is being oscillated by
the movement of the arm 55 and the result is that one set of exhaust-ports 92, 92,
is being closed and the other set opened, by the shifting of the plates 91, as
already explained. In reversing the engine, the lever 56 will be thrown over
to the other side, allowing the short lever 59 to resume its normal position against
the stop 86, and depressing the lever 58 away from its stop, thus rotating the
pinion 64 and shifting the plate 79 so as to uncover the port 77 at a different, point
from before, and at the same time through the mechanism described the exhaust
ports on the one side of the cylinder will be closed and those on the other side
opened.
The object of having the shaft 8, 9, and 10 made with different diameters, is
to facilitate the adjustment of the parts when they are assembled, and enable the
pistons 14 and 15 to be interlocked or inter-arranged the more easily.
It is unnecessary to enter into any lengthy description of the operation of my
improved engine, as the same will be easily understood by those skilled in the art.
When steam is admitted between the pistons through the live-steam inlet port
it will force the pistons forward, the rear piston acting as an abutment for the
steam. The front piston will be rotated rapidly while the rear one will rotate at
about one-fourth the speed thereof, owing to the crank and link connections with
the disc of the driving-shaft. After the front piston passes the inlet opening
and is nearing the exhaust, the steam supply will be cut off and said piston will
be rotated by expansion, and as said piston thus nears the end of its stroke, the
steam pressure will decrease, but the pull exerted on the driving-shaft will be
approximately constant as the leverage of the cranks and links will be increased,
owing to their change in position. When the piston reaches the exhaust opening
at the opposite side of the cylinder the other piston will have reached the inlet
opening, when it, will become the fast piston, and the first piston the slow one.
This operation will be kept up continuously as long as steam is supplied to the
cylinder, the speed of the two pistons alternately varying.
Referring to the modification of my invention, shown in Figures 16 and 17,
it will be observed that the cylinder 1 is formed with a hollow base 100, divided
by a central partition 101 into an inlet steam chamber 102 and an exhaust

page_text: chamber 103, and provided with inlet and exhaust pipes 104 and 105. The inlet
chamber communicates with a steam passage 106, which in turn communicates
with an inlet opening 107 in the inner side of the cylinder head 2. The exhaust
chamber communicates with an exhaust opening 108 in the cylinder. It will be
seen that the inlet opening 107 is contracted, as seen at 109, see Figure 16. The
head 2 of the cylinder 1 is provided with a boss 5, through which passes the
shaft 110, and secured to this shaft are the overlapping hubs of the pistons 111
and 112. 113 denotes spring-pressed packing strips inserted in grooves in the
pistons. Said pistons are made hollow or formed with openings 114, having
apertures 115 in the rims. The purpose of these is to counterbalance the pistons
against their centrifugal force when rotating at a high rate of speed, steam enter-
ing the pistons from the inlet opening and pressing against the rim of the cylinder.
The arrangement of the drive-shaft, the disc, the links and the cranks, is sub-
stantially the same in this modification as in the form of the invention shown
in Figures 1, 2 and 5.
With regard to the operation, it may be stated that when
the parts are in the position shown in Figure 16 steam will be admitted between
the pistons from the inlet opening, and will force the same in the direction shown
by the arrow, the rear piston acting as an abutment for the front one, and the
general movement being practically the same as already explained in connection
with Figures 1 to 5 etc.
Referring now to Figures 18 and 19, it will be seen that I have therein repre-
sented a modified form of reversing mechanism, together with certain other details.
In this modification the pistons 117 and 118 are made hollow for the sake of light-
ness, and are formed with peripheral grooves and also with side grooves to receive
suitable packing strips. Said pistons at their peripheries and sides are cut away,
as at 119, so as to leave a space between them and the cylinder. There is a
web 120 also formed near the inner end of each piston, having an aperture 121.
The purpose of said apertures and spaces is to allow steam to enter between ine
pistons and cylinder and balance the pistons. Secured to the cylinder is a steam-
chest 116 provided with a steam inlet 122. Located in the steam-chest is a slide 123
adapted to open and close steam inlet ports 124 and 125 in the cylinder head.
The numerals 126 and 127 designate exhaust pipes communicating with the
cylinder and provided with turning plugs or valves 128 and 129, with which are
connected cranks 130 and 131, pivoted respectively to opposite ends of said slide,
so that as the inlet opening at the right is opened, the exhaust opening at the left
is also opened, and rico versa. To reverse the engine, therefore, the slide 123 is
moved so as to close one set of inlet and exhaust openings and open the others. In
this form of the invention the general arrangement of pistons, shafts, disc, links, and
cranks, and the general operation of these parts, are practically the same as in
the modification shown in Figures 16 and 17.
Although I have described my engine as being used with steam, yet it must be
distinctly understood that I may employ air, gas, or any other impelling agency
for driving it.
Also the forms of the engine, as herein presented, are simply examples, and I
do not wish to be restricted thereto; but I reserve the liberty of varying the pre-
cise details as much as may be necessary to adapt the invention for actual and
successful use under various different conditions.
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:-
1. In an alternating-piston motor, the combination with the cylinder having
inlet and exhaust openings, of the pistons within said cylinder and the shaft to
which the pistons are attached, said pistons interlocking so that one applies its
power to the shaft centrally of the other.
2. In an alternating-piston motor, the combination with the cylinder having
inlet and exhaust openings, of the pistons within said cylinder and the shaft to

page_text: which the pistons are attached, and the segmental plate for graduating the size
of the inlet opening, together with means for moving said plate.
3. In an alternating-piston motor, the combination with the cylinder having
inlet and exhaust openings, of the pistons within said cylinder, the shaft actuated
by the pistons, said shaft having a differential diameter, and one piston having
hubs or sleeves that enclose the shaft on opposite sides of the single hub or sleeve
of the other piston.
4. In an alternating-piston motor, the combination with the cylinder having
inlet and exhaust openings, of the pistons within said cylinder, said pistons having
recessed sides which are connected by a port allowing steam to fill the spaces
between the piston sides and the cylinder-heads, and thus counter-balance the
pistons, substantially as described.
5. In an alternating-piston motor, the combination with the cylinder, the shaft,
and the pistons, of inlet and exhaust ports, covers for said ports, and reversing
niechanism consisting essentially of gearing for operating the steam inlet covers
and a leverage mechanism for operating the exhaust port covers, together with
a single lever for controlling both the inlet and exhaust devices, substantially as
described, and as shown in Figures 12 to 15.
6. In an alternating-piston motor, the combination with the cylinder, the shaft,
and the pistons, of inlet and exhaust ports, covers for said ports, and reversing
mechanism for shifting said covers, said mechanism being controlled by a single
hand-lever, substantially as described, and as shown in Figures 12 to 15.
7. In an alternating-piston motor, the combination with the cylinder having
inlet and exhaust openings, of the pistons within said cylinder and the shaft to
which the pistons are attached, and the segmental plate for graduating the size
of the inlet, said plate having a rack-bar that is engaged by a pinion for adjusting
the position of the plate, as set forth, and as shown in Figures 12 to 15.
8. In an alternating piston engine, the combination with the stationary cylinder,
the base of which is formed with an inlet and exhaust chamber communicating
therewith, of the rotatable shaft, the sleeve journaled thereon, the hollow pistons
adapted to receive steam from the inlet chamber and formed with inlets in the
rim, the eccentric driving-shaft, the disc secured thereto, the links pivotally con-
nected with said disc at diametrically opposite points, and the cranks secured to
said shaft and sleeve and pivotally connected with the links, substantially as
described, and as shown in Figures 16 and 17.
9. In an alternating-piston engine, the combination with the cylinder, the base
formed with an inlet and exhaust chamber, and the rim formed with an
exhaust opening, and the cylinder head formed with an inlet opening with a con-
tracted end, and the inlet pipe communicating therewith and with the inlet
chamber, of the rotatable shaft, the sleeve, the alternately operating pistons formed
with steam chambers and with openings in the rims, the eccentric driving-shaft,
the disc secured thereto, the links pivotally connected with said disc at diametri-
cally opposite points, and the crank secured to said shaft and sleeve and pivotally
connected with said links, substantially as described, and as shown in Figures 16
and 17.
10. In an alternating-piston rotary engine, the combination with the pistons
and the cylinder having inlet openings and exhaust pipes and the turning plugs
or valves in the exhaust pipes, of the steam chest, the slide for opening and closing
said inlet openings and the cranks connected with said slide and turning plugs,
substantially as described, and as shown in Figures 18 and 19.
11. In an alternating-piston rotary engine, the combination with the cylinder
provided with inlet and exhaust openings, the exhaust pipes and the turning
plugs in said pipes, the rotatable shaft, the sleeve journaled thereon, and the
pistons, of the eccentric driving-shaft, the disc secured thereto, the links pivotally
secured thereto at diametrically opposite points, and the counterbalance cranks
secured to the shaft and sleeve, and located opposite the pistons secured to the
sleeve and shaft respectively, and the steam chest, together with a slide and the

page_text: cranks connected with said slide and turning plugs, substantially as described
and as shown in Figures 18 and 19.
12. In an alternating-piston rotary engine, the combination with the cylinder
having inlet openings and exhaust pipes, the steam chest, the slide, the cranks
connected therewith and the turning plugs located in the exhaust pipes and con-
nected with said cranks, of the rotatable shaft, the sleeve, the pistons secured
thereto, cut away at the peripheries and sides, the apertured web, the packing
strips, the counter-balance crank secured to said shaft and sleeve, the links and
the eccentric driving wheel, substantially as described, and as shown in Figures 18
and 19.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.