Application for industrial invention Patent, named: "Rotary internal combustion engine with reducer and pistons that control the cycle"

The invention hereby is about a high-efficiency rotary internal combustion engine, with low fuel consumption, low environmental pollution, high reliability, long duration, simple and economic to be produced.

Existing engines on the market, Otto cycle or diesel cycle, have reached an excellent development point, but, nevertheless, they all work based on a hundred and more years old reciprocating masses kinematic mechanisms (except for some rare case of rotary engines, e.g. Wankel). I believe it is nowadays necessary to innovate internal combustion engines, simplifying the mechanics, eliminating components as camshafts, valves etc., decreasing the number of components and the production costs. It is moreover necessary to increase the efficiency and decrease fuel consumption (and, obviously, air pollution). The Wankel engine gives some answers to these issues but, due to severe reliability problems, did not broaden much. All rotary engines have indeed an important problem: the seal rings are not as reliable as the ones of traditional cylindrical pistons. For this reason I have invented the only rotary engine with above mentioned features, together with reliable rings, tipically round as the ones of cylindrical pistons. The working principle is a four-stroke Otto cycle. Fuels to be used are: gas (LPG, methane) or biogas; gasoline; partially/totally hydrogen (HHO Oxyhydrogen cells, electrolysis made, can be coupled to it). Nevertheless the kinematic mechanism, through small modifications (injection system and exclusion of the sparking plugs), could be sized for a diesel cycle: the system is not limited to the only Otto cycle then.

At the present time, there are four-stroke and two-stroke engines on the market. Taking into account that two-stroke engines will be eliminated (for obvious reasons), there will be only four-stroke engines. Such a type, considering a single reference piston, fulfills the 4 strokes after 2 revolutions of the drive shaft, that is 1 piston gets ignited every 2 drive shaft revolutions. A big advantage of my engine is that it can be designed to ignite more than once every 2 drive shaft revolutions, or, instead, to ignite once in more than 2 revolutions (always making reference to the one piston). This design choice is possible thanks to the correct combination of a planetary reducer (check following drawings and explanations), and its rotating verse with respect to the drive shaft. I can therefore build engines with a high number of ignitions, with high specific power (rotor with opposite rotating verse with respect to drive shaft), otherwise engines with a low number of ignitions and consequently low fuel consumption (in this case rotor and shaft have the same rotating verse). The choice is determined by the type of application. In other words, with the same number of cylinders and r.p.m., with respect to a traditional engine, I can differentiate the number of ignitions per revolution, and so, the frequency of intake strokes. Another big advantage is to get the typical good balancing of rotary engines and very reduced reciprocating inertia forces, thanks to limited piston strokes, and to the combination of the two motions: alternate and rotary. A further important advantage (better described below) is that external pistons move along a track that, for the sake of simplicity, is shown in the drawings as round and eccentric with respect to the rotor. Nevertheless, with a properly calculated "cam-shape" track (and so not perfectly round), it would be possible to keep a fixed volume during combustion. It is possible then to design a true constant-volume combustion, with all consequent advantages. My engine has the possibility to be spontaneously "over-intake". Actually the piston in the direction external, (check following drawings), detaching itself from the piston in the direction internal, intakes a higher volume with respect to its nominal cubature. Volumetric efficiency is therefore superior to 1. Even thermal efficiency is superior to all rotary engines, but also superior to traditional engines, due to the possibility to get a perfectly hemispherical combustion chamber. Further advantages are obtained thanks to the friction reduction. Since there is a minimal negative influence of dead centers, and since there are not components as camshafts, springs, valves etc., even the efficiency for friction is optimized.

I will describe now, after these considerations, how the invented engine works. In FIG.1 and FIG.2 drawings its main components are shown. A rotor (1 ) carrying several cylinders (4), rotates clockwise with respect to its own axis of rotation. The rotor (1 ), is rigidly linked on the two sides with, respectively, two internal gears (6), which are supported by rolling-element bearings (6.4), or hydrodynamic friction bearings (bushings); every bearing is housed on the two covers (10). The covers fasten the stator (16) with bolts. Rotor and stator are respectively eccentric. A track (14), concentric with the stator (16), is made of 2 rings (check drawings: FIG.1 , FIG.2, FIG.6). The external ring is inserted into the internal diameter of the stator, the internal ring is supported by a housing obtained inside the covers, (drawing FIG.2), so that it is extended inside the stator too. Rings can be either fix, or supported by hydrodynamic bushings (both externally and internally), so that they can rotate in order to reduce friction further. Inside the track (in between the 2 rings), the external pistons (3), which are contained in the cylinders (4), are driven through a pin (13), or it will be a slider supported hydrodynamically. In the same cylinders, also internal pistons (2) move; they are connected by connecting rods (small connecting rod (7.1 ), and main connecting rod (7.2)) to the drive shaft crank (5), the drive shaft is concentric with the rotor (check drawing FIG.3 too). Pistons, rods and crank are joined by bushings. Even the drive shaft (5) is supported by bearings or bushings (5.1 ) at its ends. Such bearings are housed inside the covers (section drawing FIG.2).

Drawing FIG.5 shows how the reducer is made of several gears. Such gears are used to connect, with a certain transmission ratio and rotation verse (not restrictive) the rotor (1) and the drive shaft (5). It is important to remark that I can create several engines with various intake frequencies, just properly designing the rotation verses, the transmission ratios, and the intake and exhaust cycles. In the engine on drawings (not restrictive), both the rotor and the drive shaft rotate clockwise, with a 1 :3 ratio. The rotor fulfills one complete revolution in correspondence of 3 drive shaft revolutions. The rotation of described parts is caused by the pushing force in between the pistons (2) and (3), check drawings FIG.1 , FIG.2, generated by the ignition of intaken fuel. The rotation of the drive shaft is indeed caused by the pistons (2), and it correspondingly generates the rotor rotation. Drawing FIG.7 shows the air-fuel mixture intake and the burst gas exhaust cycles. Since we are talking about a four-stroke engine, the cycles are: intake, compression, power (with gas expansion), and exhaust. As it can be noticed on drawing FIG.7 (they can be discerned also on drawing FIG. I), there are an intake (11 ) and an exhaust (12) duct paths, assembled on covers. The air-fuel mixture intake in the cylinders (4) and the gas exhaust are allowed by an opening (15) on each cylinder, that can be viewed also on drawings FIG.1 and FIG.4. Summarizing, when the external pistons expose the relative opening (15) into communication with the duct paths (11 ) and (12), (in drawing FIG.7 their sizes are shown in hatching), the different strokes are accomplished, as shown just on drawing FIG.7. At the end of each compression cycle, the dragging electrical contact (8.2), shown on drawing FIG.6, during its rotation gets in touch with a fixed electrical contact (pos. 9 drawing FIG.1 ), which switches on the sparking plug (8), fastened in the pistons (3). The electrical cable, properly insulated, crosses through the hollow pin (13), and ends with a shielded pipette fitting in the sparking plug. The sparking plug (8) ignites then the compressed mixture. The fixed electrical contact (9.1 ), properly insulated, is assembled on one of the two covers, and it is shown also on drawing FIG.2. All the pistons (2) and (3), have piston rings (and oil control ring) of circular shape, the same of traditional existing pistons (check drawing FIG.6 rings (3.1 ) and drawing FIG.3 rings (2.1 )). As shown on drawing FIG.6, the external pistons (3), have a hemispherical shape (3.2) on the pistons crown. On drawing FIG.4 instead, the rotor is shown, with the openings (15) surrounded by circular oil rings. The rings rotate, dragging on an area of the cover (of an appropriate material), in order to separate the areas dedicated to the duct paths (11 e 12) fastened on the cover from the areas of rotor, stator and covers dampened by the lubrication oil. The oil accomplishes the additional task to take away generated heat. The oil is put into circulation by one or more electrical pumps, or driven by the drive shaft itself. More heat is removed from the cooling liquid circulating in the hollow spaces passing through the external layer of the stator (16), as shown on drawing FIG.1. Therefore the drive shaft accomplishes the additional task to spin possible additional members (pumps and/or other...), but mainly to transmit the motor driving force to a gearbox or similar. Once the rotor has fulfilled a 360° rotation, the drive shaft has instead completed 3 whole rotations, and the pistons have fulfilled the cycle sequence (intake, compression, power and exhaust) totally 3 times. And so 1 rotation of the rotor is given by 3 ignitions. If compared with a traditional engine, this is a 3 cylinders engine, with one ignition of each piston at every 3 revolutions of the drive shaft, and at every revolution of the rotor. Find here below a sizing table with some possible engine lay-out configurations based on the design of the reducer and on the number of pistons, with consequent different frequencies (more configurations are possible)

Drawing FIG.5: reducer description.

The reducer can be made like this (not restrictive): internal gear (6), nr. of teeth=90, rigidly connected with the rotor (1) and supported by 2 bearings/bushings (6.4) (shown on drawing 1 b), housed in the covers. The gear (6.1), with 30 teeth, is installed on the drive shaft (5). Lastly, the gear (6.2) (nr. of teeth = 25), and the gear (6.3) (nr. of teeth = 20), rotate on bearings housed on pins that are rigidly fixed on the cover. The transmission ratio in this case (not restrictive), is 3:1 , that is: 3 revolutions of the drive shaft make 1 rotor revolution. Both rotate clockwise (not restrictive).