Improvement in Rotary Engines.
Year: 1898

page_text: Date of Application, 9th May, 1898-Accepted, 3rd Sept., 1898
COMPLETE SPECIFICATION.
Improvement in Rotary Engines.
I, NELSON WITTS, of Alma City, County of Waseca, and State of Minnnesota,
United States of America, Gentleman, do hereby declare the nature of this inven-
tion, and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
-
My invention relates to an improvement in rotary engines, and more particu-
larly to a reversible rotary steam engine having a revoluble wheel provided
with radially movable pistons; and it has for its object to provide a reversible
rotary steam engine which is simple and inexpensive in construction, easy and
effective in operation, which will effect a great saving of steam, and in which
friction shall be reduced to as small an extent as is consistent with the proper
packing of the joints, compensation made for wear, pressure so regulated on the
pistons as to balance the wheel and facilitate the revolution of same, and other.
advantages as hereinafter set forth.
My invention consists of a rotary engine having a casing, a wheel arranged in.
said casing, and having radially-movable pistons, a shaft to which the wheel is secured,
means for supplying the motive fluid to and for exhausting the same from the
engine; means for compensating for wear and packing the piston wheel, and other
features, and in the construction, combination, and arrangement of the several
parts comprising the same, as more fully hereinafter described and claimed.
My invention is illustrated in the accompanying drawings in which: -
Fig. 1 is an end view partly in section.
Fig. 2, a front view partly in section of one section of the casing.
Fig. 3 an inner face view partly in section of the other section of the casing-
Fig. 4 a plan view with the supports for the driving shaft and the inlet valves
not shown.
Fig. 5 a horizontal section on line of Fig. 3, looking upward when the
sections of the casing are together.
Fig. 6, a detail perspective view of one of the radial pistons.
Fig. 7 a detail perspective view of one of the check valves.
Fig. 8, a detail perspective view of the combined inlet and outlet reversing
valve.
In the drawings in which like letters of reference denote like parts throughout
the several views, A, represents the casing consisting of two sections B, C, secured
together by bolts D, each section having feet E, on which the casing is supported.
F, is the drive shaft of the engine supported in holes G, in the sections of the
casing and in stuffing boxes H on the outer faces thereof, and the ends of said
shaft-supported in suitable journal boxes on uprights I, I'
The section B is provided on its inner face with annular flange J, a circular
projection or hub K, and an 'annular recess L, between said flange and hub.
The section C is provided on its inner face with an annular flange M, a circular
projection or hub N, and an annular recess O, between said flange and hub, said
hub N, provided with a central circular recess P, and a cam groove Q.

page_text: R, is the piston wheel provided with a hub S, and a hole T, through said wheel
and hub adapted to receive the shaft F, on which said wheel is mounted. One
face of said wheel is provided with an annular rim U, which fits over the hub K,
of the section B, and its other face V, provided with an annular rim W, secured
thereto by bolts W', which fits over the hub N, of the section C, and is provided
with slots X, in its outer edge having guides Y, and recesses Y¹. Z, are radial-
slots also in the face V, of the wheel. 1, are pistons located and adapted to
reciprocate in slots 7, the inner ends of said pistons being provided with studs or
pins 2, on which are mounted antifriction rollers 3, adapted to engage and move
in the cam slot Q, of the section C, and the outer ends thereof with a head 4,
provided with top plate 5, adapted to be scated in recesses Y¹, and side flanges 6,
adapted to slide in guides Y.
7, are packing rings which surround the hubs K, and N, of the sections and
are held in contact with the rims U, and W, of the wheel by spiral or other
springs 8, for the purpose of packing and compensating for any wear of the same.
9, is the valve chest at the upper end of the casing having an abutment 10
which projects into the casing and bears against the periphery of the piston wheel.
11. is a spring packing plate seated in a recess 12 in the abutment 10, and
held in contact with the periphery of the piston wheel for the purpose of com-
pensating for wear and effecting a steam tight joint.
13, and 14, are inlet openings in the valve chest of the section, C, and 15,
and 16, are outlet openings in the section B, communication being established at
the bottom between said inlet and outlet openings by means of ports 17, and 18;
19 and 20 are check valves in the inlet openings 13, and 14, respectively. 21,
is a steam inlet or supply pipe and 22, a steam outlet or exhaust pipe, said pipes
being supported in plates 23, screwed to the top of the valve chest, the inlet
pipes communicating with the inlet openings of the valve chest, and the outlet
pines communicating with the outlet openings of the valve chest.
24, is a combined inlet and outlet reversing valve provided with notches 25,
and 26, the end having the notch 25 being situated in and adapted to reverse
the admission of steam into the inlet pipes, and the other end having the notch 26
being situated in and adapted to reverse the exhaust of steam from the outlet
pipes, and 261 a lever for operating the said valve 24.
27. and 28, valve stems on the valves 19, and 20, respectively mounted in
suitable bearings in the top of the uprights I¹.
29. and 30, are loosely mounted flanged pinions mounted on the shafts 27,
and 28, respectively and each provided with a lug 31.
32. and 33. are discs rigidly secured on the stems 27, and 28, respectively and
provided with lugs 34, and 35, and 36, levers for throwing the valves into or out
of use.
37, a cog wheel mounted on the drive shaft F and meshing with the pinions 29,
and 30, and thereby communicating motion to the same. 38, a belt wheel on
the drive shaft F, for transmitting power.
39, is a cock for drawing off the water resulting from the condensation of
steam.
The operation is as follows: The valves and pistons being in the position shown
in the drawings, steam is admitted constantly through inlet pipe 21, into the
inlet opening 13, and passes through the port 17, into the space between the
casing and the periphery of the piston wheel. and acting upon the piston and
the abutment which it has passed revolves the piston wheel and shaft one sixth of a
revolution, revolving the cog wheel 37, one sixth of a revolution which in turn
revolves the pinion 30, on valve stem 28, and the valve 19, on said stem a full
revolution and thereby causing the valve to close and open cutting off and
admitting the steam, then the expansive force of the steam between the abutment
and piston will cause the piston wheel to revolve one twelfth of a revolution, in
the meantime another piston has passed under the abutment 10, and has been
moved outwardly by the cam groove Q. This operation is continued and when

page_text: the piston wheel has revolved until the first piston operated upon begins to be
drawn in by the cam groove Q, the steam first admitted exhausts by passing
through the port 17, outlet opening 15, and through outlet or exhaust pipe 22.
When it is desired to reverse the engine the check valve 19, is thrown out and
the tooth 34, on the disc 33, disengaged from the tooth 31, on the pinion 30,
and the valve 20, thrown in, the reversing valve 24, given half a turn, when the
engine is ready to run in the opposite direction.
While steam in this instance, has been referred to as the motive force any other
suitable fluid might be used.
I do not limit myself to special forms or details of construction, as I intend to
change the form of construction as may be found expedient and within the spirit
of my invention.
Although a closed casing is shown a partially open casing can be used especially
when it is to be used as a water wheel,
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. A rotary engine comprising a casing having a motive fluid space, a valve
chest provided with an abutment, inlet openings, and outlet openings, ports
connecting the said inlet openings with the outlet openings, valves for the inlet
openings, a valve for reversing the inlet and exhaust of steam to and from the
motive fluid space, and a piston wheel in said casing provided with radially
movable pistons, adapted to be projected into and withdrawn from the motive
fluid space, substantially as described.
2. A rotary engine comprising a casing having a motive fluid space, a valve
chest provided with an abutment, inlet openings, and outlet openings, ports con-
necting the said inlets openings with the outlet openings, valves for the inlet
openings, a valve for reversing the inlet and exhaust of steam to and from the
motive fluid space, a cam groove in the casing, a piston wheel provided with
radial pistons having antifriction rollers, adapted to engage the cam groove for
the purpose of projecting the pistons into and withdrawing the same from the
motive fluid space, substantially as described.
3. A rotary engine comprising a casing having a motive fluid space, a valve
chest provided with an abutment, inlet openings, and outlet openings, ports for
connecting the said inlet openings with the outlet openings, valves for the inlet
openings, and means for automatically rotating the same, a valve for reversing
the inlet and exhaust of steam to and from the motive fluid space, and a piston
wheel in said casing provided with radially movable pistons adapted to be auto-
matically projected into and withdrawn from the motive fluid space, substantially
as described.
4. A rotary engine comprising a casing having a valve chest provided with an
abutment extending into the casing, a shaft revoluble in bearings in the casing,
a piston wheel on the shaft in said casing, a motive fluid space around a portion
of the piston wheel, pistons movable radially on said piston wheel, and means for
projecting the pistons into the motive fluid space as soon as they clear the abut-
ment, and to retract said pistons before they reach the abutment again, inlet
openings, and outlet openings in said valve chest communicating with the motive
fluid space and a fluid supply, valves located in said inlet openings, a combined
inlet and outlet reversing valve located in the inlet and outlet pipes, for the
purpose of reversing the inlet and exhaust of steam, substantially as described.
5. A rotary engine comprising a casing having a wheel, a motive fluid space, a
valve chest, inlet openings, and outlet openings, ports connecting the said inlet
openings with the outlet openings, valves for the inlet openings, means for rotating
said valves and throwing them into and out of operation, and means for reversing
the inlet and exhaust of steam to and from the motive fluid space, substantially
as described..

page_text: 6. A rotary engine comprising a casing having a motive fluid space, a valve
chest, inlet openings, and outlet openings, ports connecting the said inlet open-
ings with the outlet openings, valves for the inlet openings, means for reversing
the inlet and exhaust of steam to and from the motive fluid space, a drive shaft
mounted in said casing, a wheel in the casing mounted on said shaft, and means
for communicating motion from said shaft to the check valves for the purpose of
rotating the same, substantially as described.
7. A rotary engine comprising a casing having a drive shaft mounted
thereon, a wheel in the casing mounted on said shaft, a
cog wheel
mounted on said shaft outside the casing, a motive fluid space, a valve chest,
inlet openings, and outlet openings, ports connecting the said inlet openings with
the outlet openings, valves for the inlet openings provided with stems having
flanged pinions mounted loosely thereon, adapted to engage the cog wheel on the
drive shaft, clutch mechanism rigidly secured on said stems adapted to engage
said pinions and cause the same to turn therewith, and means for reversing the
inlet and exhaust of steam to and from the motive fluid space, substantially as
described.
8. A rotary engine comprising a casing, a wheel therein, yielding rings between
the outer faces of the rim of the wheel and the casing adapted to be held in
contact with the said outer faces of the rim of the wheel, for the purpose of
packing and compensating for wear on said wheel, substantially as described.
Dated the 12th day of April 1898.
W. P. Thompson & Co.,
NELSON WITTS.
322, High Holborn, London, W.C., Patent Agents for the Applicant.