WO1986005548A1

WO1986005548A1 - Rotary engine

Info

Publication number: WO1986005548A1
Application number: PCT/EP1986/000130
Authority: WO
Inventors: Giuseppe Soave; Giuseppe Ruzzenenti
Original assignee: Venturelli, Giacomo
Priority date: 1985-03-19
Filing date: 1986-03-10
Publication date: 1986-09-25
Also published as: ES553621A0; EP0229766A1; ES8701897A1; AU5622186A; IT8584916A0; CN86101810A

Abstract

A rotary engine comprises a casing, a twin rotor assembly mounted for rotation in the casing and having two co-axial spindles projecting from the casing, a gear drive, and one output shaft, the gear drive having two elliptical gear trains each arranged to operatively connect a respective spindle to the output shaft.

Description

"ROTARY ENGINE" Technical Field

This invention relates to a rotary engine for use in combination with drives arranged to convert input pulsating power into uniform rotary motion.

An object of the present invention is to provide a rotary engine which is highly effective to yield improved engine output.

According to the invention there is provided a rotary engine comprising a casing, a first and a second rotor assembly, mounted for rotation in the casing, each rotor assembly comprising at least one radially extending sector or jaw and a spindle, a spindle of one rotor assembly being axially aligned with the spindle of the other rotor assembly, two gear drives and an output shaft, each gear drive comprising two elliptical gears and being arranged to operatively connect a respective spindle to the said output shaft, thereby causing speed differentials between said first and second rotor assemblies.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be more clearly understood from the following description of a few specific embodiments thereof, given herein by way of examples with reference to the accompanying drawings, in which:

Figure 1 shows a diagrammatic side section view of an engine according to the invention; Figure 2 shows a diagrammatic front section view of the engine of Figure 1 showing the rotor arrangement during its exhaust and intake strokes;

Figure 3 is a diagrammatic section view similar to Figure 2 showing the rotor arrangement during the power and end-of-exhaust stroke;

Figure 4 is an exploded perspective diagrammatic view showing the two rotor assemblies; Figure 5 is a diagrammatic view similar to Figure 1, illustrating another embodiment of the invention;

Figure 6 is a left side view of the device of Figure 5; and

Figure 7 is a right side view of the device of Figure 5.

WAYS OF CARRYING OUT THE INVENTION

With reference to the above figures, reference numeral 1 generally indicates an internal combustion engine which comprises a cylinder or casing 2, and a rotor mounted for rotation in the casing 2 and comprising twin rotor components indicated at 3 and 4, respectively, and arranged to cooperate with one another. Each rotor component is rigid in rotation with a respective shaft 5, 10, each of which are operatively connected to a respective drive generally indicated at 7 including two elliptical gears meshing with, and in opposition to, one another.

The rotor component 3 comprises a central cylindrical holder 8, from which two jaws 9 and 9' diametrically opposite jaws or sectors 9 and 9' axially extend so as to project from the body 8. Likewise, the rotor component 4 is provided with a central cylindrical holder 10 similar complementary to the holder 8 and with jaws or sectors 11 and 11', also diametrically opposite to one another and axially extending with respect to the holder 10.

The two rotor components 3 and 4 are assembled in such a way that the shaft 5 fits inside the hollow or tubular shaft or holder 10, with the overhanging portions of the jaws 9-9' and 11-11' matching with each other so that their respective holders 10 and 8 abut one against the other, thus forming two coaxial rotor assemblies.

The rotor assembly is accommodated free to rotate inside the cylinder or casing 2 and is also connected directly to the drives 7 through the shafts 5 and 10.

In the assembled condition, the rotor assembly delimits a series of chambers inside the casing 2. Such chambers are inner spaces in which the cycle strokes of an end thermal gasoline engine, e.g. a four-stroke cycle engine, as shown in Figures 2 and 3, can occur.

During a power stroke, the jaws or sectors 9-9' and 11-11' are arranged one relatively to the other as shown in Figure 3.

Fuel combustion causes the jaw 9 to move forward (clockwise direction) at an accelerated rate up to the end of the exhaust stroke. At the same time, the jaw 9' integral with it is subjected to the same acceleration throughout the compression stroke. Similarly, the assembly 4 experiences deceleration while the assembly 3 is being accelerated, whereas when the assembly 4 going through its power stroke, it will be accelerated and the assembly 3 decelerated accordingly. This differential in the speed of rotation between assemblies 3 and 4, is due to the arrangement of the elliptical gear drive 7 which makes it possible, to obtain power, exhaust, intake, and compression chambers varying their capacity according to a specifio sequence which depends, among others, on the degree of eccentricity of the elliptical gears. For each complete revolution of each rotor assembly, 3 and 4, four strokes occur i.e. intake, compression, power, and exhaust strokes, and one spark plug 12 is provided to prime fuel combustion. The embodiment shown in Figures 5,6 and 7 (where the same or similar parts to those of Figures 1 to

4 are identified with the same reference numerals) comprises a drive 13 comprising two identical gear trains. More specifically, the hollow shaft 10 projects from the cylinder or casing 2 and is designed to drive a first gear train constituted by a circular gear wheel 14 keyed to the hollow shaft 10, a pinion gear 15 meshing with the gear wheel 14 and being journalled on a rotatable intermediate or auxiliary shaft 16 having its axis x-x parallel to the axis y-y of the shafts or spindles 5 and 10, a first elliptical gear 17 mounted for rotation on the shaft 16 and rigid in rotation with the pinion gear 15, and a second elliptical gear 18 keyed to an output shaft 19 having an axis z-z parallel to the axes x-x and y-y. The spindle 5, which extends throughout the hollow shaft 10, projects from both the cylinder 2 and the shaft 10, and is arranged to drive a second gear train. If desired, the spindle

5 could project from the cylinder 2 at Its end far from the hollow shaft 10, while being in alignment thereto. In that case, the engine 1 would be located between the two gear trains.

The second gear train comprises a circular gear wheel 20 rigid in rotation with the spindle 5, a pinion gear 21 meshing with the gear wheel 20 and being keyed to the intermediate or auxiliary rotating shaft 16, an elliptical gear 22 also keyed to the shaft 16, and a second elliptical gear 23 keyed to the shaft 19. The elliptical gears 17 and 18 of the first gear train are identical with, and outphased by 180°, from the corresponding elliptical gears 22 and 23 of the second gear train, when aligned along their major axes.

The shaft 16 could also be a shaft 20 (i.e. a non-rotating shaft), in which case the gears 15, 17 and 21, 22 would be mounted for rotation on it, the gear 15 being rigid in rotation with the gear 17 and the 21 with the 22. With such a drive 13 which has 1:2 drive ratio between the spur gears 14,15 and 20,21, for each full revolution through 360° of the output shaft 19, there occur a number of relative accelerations and decelerations of the rotors 3 and 4, which result in a corresponding number of volumetric changes between the jaws or sectors 9,9' and 11,11', thereby providing two complete intake, compression, power, and exhaust stroke cycles typical of a four-stroke cycle engine. The number of engine cycles may be even higher than two, namely four, six, etc. (but in all cases an even number), if provided that drive connection between the spindles 5 and 10 and the elliptical gearings of course through two pairs of circular gears 14,15 and 20,21 having respective 1:4, 1:6, etc. drive ratios, and if the number of the rotor jaws or sectors 9,9' and 11,11' is correspondingly increased, e.g. 4,6, etc. By omitting the two pairs of spur gears, as in the embodiment of Figure 1, the rotary engine may be used as a compressor or a pump, since it effects one acceleration stroke and one deceleration stroke for each revolution. In other words, it can provide two instead of four strokes. In that case, the shaft 19 would be the output shaft and the spindles 5 and 10 driven shaft, each designed to drive a rotor advantageously provided with one sector or jaw, 9 or 11. The flare angles of the jaws 9,9' and 11,11' of the rotor assemblies are correlated directly to the degree of eccentricity of the elliptical gears, the eccentricity being in turn also related to the maximum torque of the engine 1. Thus, as an example, if α is the inner angle between two straight lines joining the centre of rotation of each elliptical gear to the points of intersection of its minor axis with its respective pitch ellipse, and β is the outer angle between those same lines (Figure 6), then the corresponding flare angles of the sectors or jaws 9,9' and 11,11' is α/2 and β/2 , respectively, if the drive ratio is 1:2, or α/4 and β/4 if that ratio is 1 :4, and so on.

At a 1:4 drive ratio, each complete revolution through 360º results in the rotors (spindles 5 and 10) undergoing alternately four acceleration and four deceleration strokes, which results in a virtually continuous and uniform motion of the shaft 19. The angles α and β cannot have the same value, because they would then have zero eccentricity, and accordingly, zero acceleration and deceleration (no relative out-phasing).

Figures 5-7 also show a specific peculiar design of the hollow spindle 10 which extends to a point close to the gear wheel 20, where it carries an end bush or bearing 25 for the spindle 5.

If desired, the jaws or segments 9,9' and 11,11' could have an annular or toric configuration, and fit in respective seats formed in the casing 2.

Claims

CLAIMS 1. A rotary engine comprising a casing, a first and a second rotor assembly, mounted for rotation in the casing, each rotor assembly comprising at least one radially extending sector or jaw and a spindle, a spindle of one rotor assembly being axially aligned with the spindle of the other rotor assembly, two gear drives and an output shaft, each gear drive comprising two elliptical gears and being arranged to operatively connect a respective spindle to the said output shaft thereby causing speed differentials between said first and second rotor assemblies. 2. A rotary engine as claimed in Claim 1, wherein the spindle of one rotor assembly is hollow and rotatably receives in it the spindle of the other rotor assembly. 3. A rotary engine as claimed in Claim 1 or 2, wherein each gear drive comprises an intermediate or auxiliary shaft extending parallel to the spindle and the output shaft, a pair of meshing spur gears for transmitting the motion between the spindles and the auxiliary shaft, and a pair of elliptical pair for transmitting the motion between the auxiliary shaft and the said output shaft, one elliptical gear being rigid in rotation with a βpαr gear, whereas the other elliptical gear is keyed to the said output shaft.