Rotary Engines With Free Reciprocating-Rotating Pistons and Jet Thrust Drive

This invention relates to improved rotary machines and is more particularly concerned with rotary engines having freely reciprocating pistons in rotors and which produce rotational torque by reactional forces on the pistons and additionally by jet thrust of exhaust from the rotor periphery.

In prior art machines producing their torque by reactional forces acting upon pistons in cylinders carried by a rotor, the rotor cylinders are deployed radially, and with multi-arched stator casings the piston strokes have to be short and working pressures very high. In general such machines are employed only for hydraulic machinery, their characteristics being undesirable for an expansive-medium engine application. Furthermore, with admission and exhausting of the medium being effected from the same port in a hub, the resulting flow regime is inappropriate for high efficiencies.

It is a principal object of the invention to provide improved rotary-reciprocating piston machines, and particularly engines which produce rotational torque by reactional forces acting on the pistons from stator walls and additionally by the thrust of gases exhausted from rotor cylinders, uniflow of the working medium being maintained, and torque, overall efficiency and fuel economy being increased.

Another object of the invention is to provide increased and even torque in rotary engines by employing pairs of opposed rotor cylinder cavities with axes staggered at opposite sides of the rotor axis.

Another object of the invention is to provide improved engines employing tubular piston tail-rods eccentric to the piston axis to enable the jetting of exhausted medium through tail-rod ducts and also to prevent revolving of the pistons, thereby enabling the use of rollers on the piston tops and reducing the frictional loses between piston tops and the stator inner wall.

Another object of the invention is to attain more even torque by employing twin opposedly-arched stator casing walls in engines of the foregoing type.

Still another object of the invention is to provide a long-stroke, dynamically-balanced rotary piston engine by employment of twin laterally stepped stators with an eccentrically journalled rotor having groups of twin freely-reciprocating pistons in isolated cylinder cavities similarly fitted with tubular tail-rods having holes for discharging of exhausted medium to be jetted from rotor nozzles, thus increasing the duration of the stroke and increasing efficiency.

Yet another object of the invention is to provide an improved engine employing novel arrangements of inlet ducts and ports and exhaust slide-valves.

Still another object of the invention is to provide a novel rotary engine with cooperating sets of medium-compressing and power pistons.

It is also an object of the invention to provide a simple, rugged engine having the least amount of parts, which can be built and maintained at the least cost and yet can run on any expansive or explosive medium, including detonating charges or capsules, for which a charging-belt arrangement is provided.

The invention will be further described in conjunction with the accompanying drawings, which illustrate preferred and exemplary embodiments of machines in accordance with the invention, similar parts being designated by similar reference numbers, appropriately primed in different embodiments, and wherein:

FIG. 1 is a transverse sectional view of a rotary engine in accordance with the invention taken along line 1--1 of FIG. 3;

FIG. 2 is another transverse sectional view of the engine taken along line 2--2 of FIG. 3;

FIG. 3 is a longitudinal sectional view of the engine of FIGS. 1 and 2;

FIG. 4 is a transverse sectional view of another embodiment of the invention, taken along line 4--4 of FIG. 5;

FIG. 5 is a longitudinal sectional view of the engine of FIG. 4;

FIG. 6 is a horizontal sectional view taken generally along line 6--6 of FIG. 4, but showing structure particularly designed for an internal combustion embodiment;

FIG. 7 is a horizontal sectional view, similar to FIG. 6, of a modified engine fitted with exhaust controlling slide-valves.

Referring to the drawings and initially to FIGS. 1, 2, and 3, a machine in accordance with the invention, such as an engine working with expansive media like steam, hot air or explosives, comprises a stator casing 10 having twin opposed cylindrical casing sections with arched inner walls 11 defining, with a cylindrical rotor 20, opposed crescent-shaped chambers 12 meeting at an axial plane of the engine containing the rotational axis of the rotor and producing dead points 13. The rotor axis is eccentric to each stator casing section. The stator also has end walls 14 and 16 with trunnions accommodating roller bearings 80 for opposite power shaft extensions 25 of the rotor.

The rotor has two sets of twin opposed cylindrical cavities 30, each set having connected cavities with axes staggered at opposite sides of the rotor axis. In the form shown, one set of cavities is displaced 90.degree. from the other set about the axis of the rotor. In the cavities are provided freely reciprocating pistons 40 having tapered slotted heads fitted with rollers 41 by piston pins 42. The pistons also have piston tail-rods 44 eccentric to the piston and cavity axes and arranged in wells in the rotor, so as to guide and prevent rotation of the pistons. The tail-rods are hollow, having ducts 46 and holes 45 for the passage of the exhausted medium from the cylinders by means of ducts 55 and orifices 56 on the rotor periphery. The exhausted medium is jetted into the stator chambers 12 and out of the engine, or to a condenser, through outlets 19.

The left-hand side of FIG. 3 shows one arrangement for admitting an expansive working medium, the left rotor shaft 25 being provided with an opening 50 for admission of the fluid medium into adjacent cylinders through duct 51. A cylindrical slide valve 60 with a throat 61 mounted in hole 24 across rotor shaft 25 with its tips sliding or rolling inside an eccentric cam ring 62 is cyclically forced to reciprocate as the rotor turns, periodically leaving duct 51 open for the flow of the working medium into the associated cylinders 30. A similar arrangement may be provided for the right-hand side of the engine although a different arrangement is shown and will be described hereinafter.

In operation of the engine, the admitted expansive medium acting over the bottom of the pistons forces rollers 41 into steady rolling contact with stator inner walls 11, whereby the resultant reactional forces on the periphery of rollers 41 induce rotation of the rotor, while the expanding working fluid in the cylinders flowing through piston rod holes 45 and ducts 46 of tail-rods 44 is ejected into ducts 55, producing torque while acting on bends 54 and jetting out of orifices 56 to produce thrust to rotate the rotor 20. When the pistons have moved outwardly to the greatest extent, the reactional forces acting on piston rollers 41 by stator walls 11 force the pistons inward as the rotor turns, the jet thrust of the exhausted medium through orifices 56 increasing in intensity as the pistons compress the working medium on the return stroke and force the exhaust out of nozzle orifices 56.

For the operation of the machine by employment of detonating capsules, an arrangement as shown at the right-hand side of FIG. 3 may be employed. A spring-loaded needle 90 is mounted in stator trunnion 18 near end wall 14 and is actuated by a trigger mechanism having a lever 91 whose end 92 extends into grooved cam-track 101 at the inner face periphery of the flywheel or gear 100. The capsule-charges insertedly mounted on the charge belt 95 moving crosswise to the engine axis through a belt-slit in the stator trunnion meet cyclically with a port on the periphery of right shaft 25 when the needle strikes, and exploding gases issued by the detonation rush into the adjacent cylinders through duct 51 and orifice 52, forcing the pistons to move outwardly.

Irrespective of which inlet arrangement is used, rotation of the rotor is produced by the reactive force on the rollers and by the gases ejected through holes 45, ducts 46, ducts 55 and orifices 56 and into the stator chambers, which serve as exhaust manifolds for discharging the exhaust gases into open air or to a condenser through exhaust outlets 19 on the stator wall periphery as stated previously. The outward movement of the pistons is aided by centrifugal force.

In the engine shown in FIGS. 4, 5, and 6, the rotor 20' has sets of isolated opposed twin cylindrical cavities 30', the sets in this case having axes parallel to each other instead of displaced by 90.degree. as in the previous embodiment. The stator is formed of two successive laterally-stepped cylindrical sections 10'a and 10'b, as shown in FIG. 5, joined by flanges 15'. The axes of the sections are parallel and at opposite sides of the rotor axis, so that the cylindrical rotor is oppositely eccentric in the stator casing sections, sweeping one section at one side and the other section at the opposite side. Thus when piston 40' of one set arrives at the bottom of its in-stroke the other piston of that set arrives at the top of its outstroke, and vice versa for the pistons of the other set, producing acting force couples around the complete revolution of the rotor and balanced harmonic torque, as can be perceived from FIG. 4. In FIG. 5 two alternative types of arrangements for inlet ducts are shown. The left-hand side comprises a cylindrical hub body 18' stationary inside the drive shaft 25' and provided with an inclined duct 51' extending from inlet 50' to meet cyclically and alternately with ports 52' of the adjacent cylinder cavities as the rotor turns. The right-hand side comprises an inlet duct arrangement including an inlet duct 51'a for each adjacent cylinder cavity, which mates with an arcuate admission channel 50'a for a portion of a revolution of the rotor. Any arrangement may be used at either side of either embodiment.

FIG. 6 shows an arrangement of ducts in an internal combustion embodiment of the invention, a pair of cylinders on the left serving as compressors (C) and a pair of cylinders on the right developing power (P). Admission of working fluid is performed when an inlet port 51" of a cylinder at the left side meets cyclically with open part 50" of an annular channel in stator wall 16" rather than meeting with a blocking part 69". The working medium after being compressed by a compression cylinder 30", is ejected into duct 52" through the inner duct 46" and port 45" on piston tail-rod 44". Over-pressure pushes check valve ball 53" against a return spring to open duct 52" for passage of the compressed medium into the corresponding power cylinder 30" while a spark-plug or heating coil 70" ignites it. Sliding exhaust control valves 72" have throats 61" which reciprocate across associated exhaust ducts 55" and cyclically open or close them alternately. The exhaust valves are controlled from valve control channel 65" by annular cam-wedge 66" at one end against which balls 63" are urged by springs at the other end. In FIG. 6 the shaded left cylinder 30" is seen admitting working fluid, the unshaded left cylinder 30" is shown at the end of compression, transferring the medium into the unshaded right cylinder 30" starting the power stroke, and the shaded right cylinder 30" is shown jetting the exhaust.

FIG. 7 shows a double-throated exhaust control valve system for an expansive-medium engine, such as the engine of FIG. 4, in which cylindrical slide-valves 72'" each having two throats 61'" are mounted along the rotor to reciprocate across associated pairs of exhaust ducts 55'" (as shown in phantom in FIG. 4). One valve is thrust to the right-hand control channel by a left-hand cam-wedge 66'", freeing the nozzle 56'" of a lefthand cylinder 30'" for jetting the exhaust into the stator, while the nozzle belonging to the corresponding right-hand cylinder is blocked. On the opposite side of the rotor the other slide valve 72'" is thrust to the left by right-hand cam-wedge 66'" into left-hand channel 65'", freeing the jetting nozzle of a right-hand cylinder and blocking the channel of the corresponding left-hand cylinder. The exhaust valves are moved to the left and right alternately. The cylinders may have their intake ducts opened and blocked alternately, as in FIG. 5, for example, as is conventional in expansive medium engines.

While preferred embodiments of the invention have been shown and described, it will be apparent to those skilled in the art that changes can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims.