WO2003091544A1

WO2003091544A1 - Rotary internal combustion engine

Info

Publication number: WO2003091544A1
Application number: PCT/LT2002/000005
Authority: WO
Inventors: Aleksandras Balcikonis
Original assignee: Aleksandras Balcikonis
Priority date: 2002-04-26
Filing date: 2002-07-01
Publication date: 2003-11-06
Also published as: LT5113B; LT2002050A; AU2002321937A1

Abstract

The present invention relates to internal combustion engines with rotors mutually intermeshing through cavities and lobes of their flank surface, thus, forming working chambers which vary in volume. The aim of the invention is to increase the power of the engine without increasing the dimensions of the engine and to simplify the combustion mechanism. In the rotary internal combustion engine, where there is a casing (1) with two cylindrical chambers (2 and 3), two parallel shafts connected by a synchronising cogged gear with the rotors (4 and 5) being mounted on those shafts and mutually intermeshed by the cavities and lobes of their flank surface, the mentioned aim of the invention is reached by the fact that one female rotor has two cavities whereas another one, male rotor, has one lobe; the ignition plug is built in the casing near the position where the lobe of the male rotor starts coming out of the interaction of maximum pressure. References to fig. 1.

Description

ROTARY INTERNAL COMBUSTION ENGINE

The present invention relates to internal combustion engines with rotors mutually intermeshing through cavities and lobes of their flank surface, thus, forming working chambers which vary in volume.

A known rotary internal combustion engine is made of a casing with two parallel intersecting cylindrical chambers where there is a female rotor with cavities and a male rotor with lobes mounted on parallel shafts connected by a synchronising cogged gear; the number of cavities is greater than that of lobes, the dimension of the rotors in the direction of the axis are L=0,75 -1,5 of the chord of the rotary circle determining the width of the cavity, and the chord determining the width of the lobe C_R=0,33-0,55 of the distance between the centres of the rotors. In the cavities (or on the lobes) there are foreseen ignition plugs (SU patent No 565635, Int. Cl. F02B55/00, published on 15.07.1977).

The shortcoming of this rotary internal combustion engine is that it has not been taken into account that in the presence of the same diameter of the rotors a lower number of cavities predetermined thereby may deliver a greater content of combustion mixture to the combustion chamber than in the case of a higher number of small cavities. Therefore, if greater cavities were available and the engine dimensions remained the same, greater power could be achieved. Another shortcoming is that upon igniting the mixture in each of the cavities, the combustion system becomes complicated since it is necessary to carry out the electrical contact of the rotating surfaces. This shortcoming may be avoided in the case of the internal combustion engine in accordance to patent application No WO 91/10052, Int.Cl. F02B53/08, published on 11.07.1991, where the combustion chamber is in the casing between the compressor and expander rotors. However, the dimensions of the engine grow more than twice since the size of the rotors of the introduced expander mechanism in the direction of the axis is greater than that of the compressor. The prototype of the present invention is that patented on the basis of the patent

SU No 565635.

In the proposed rotary internal combustion engine having two parallel intersecting cylindrical chambers with two parallel shafts connected by a synchronising cogged gear and two rotors being mounted on those shafts and being mutually intermeshed by the cavities and lobes of their flank surface according to the invention the shortcomings of the prototype are eliminated by providing one rotor with two cavities and another one with one lobe. According to the invention the ignition plug is foreseen in the casing and is beyond the limits of the cavity when the ignition is taking place.

The engine may have more than one pair of female and male rotors with the lobe of male rotors being located differently with regard to the circle of the shaft.

In the engine the female rotor with cavities may intermesh with lobes of two male rotors present on the shafts that are parallel to the shaft of the female rotor with cavities.

The example of carrying out the invention is described making references to the drawings where fig.l - sectional view of the engine; fig.2 - view of the engine according to A-A fig.1 ; fig.3 - axonometric view of the female rotor with cavities; fig.4 - axonometric view of the male rotor with lobes; fig.5 - axonometric view of the 4 male rotors on the shaft with different locations of lobes; fig.6 - interaction of the female rotor with cavities with 2 male rotors having the lobe; fig.7 - scheme of determining the curvature of the contacting surfaces of the male rotor with the lobe.

The engine has a casing 1 with intersecting cylindrical chambers 2 and 3 where there is a female rotor 4 with two cavities and a male rotor 5 with one lobe (fig.l). The rotors are mounted on parallel shafts 6 and 7 connected by a synchronising cogged gear 8 which ensures the ratio i=l:2 of the speeds of rotors 4 and 5. In the casing there is mounted an ignition plug 9 as well as the channels for scavenging and fuel feed 10 and 11.

The radius of the rotor 4 equals to the radius R of the cylindrical chambers (fig.1,7). The curvature radius of the surface of the cavities of the female rotor is almost as the radius R. The curvature radius of the protuberant not-lobe surface of the rotor 5 equals R; further there is a surface with a variable curved radius p, passing to the surface with the curvature radius p =A-R where A is the distance between the axes of the rotors. The rotor 5 is symmetric with regard to its longitudinal axis; therefore, it is sufficient to determine the contacting surface of a single side of the rotor. When the rotors 4 and 5 are in the position as in fig.1,7, the working chamber is minimum. When coming out of and going into this full-contact position, a hermetic contact of the rotor 5 must be ensured with the edge of the cavity while this edge moves along the line of the circle OO' (fig.7) with the radius R.

In the beginning of the contact the contacting surface of the rotor 5 has the same radius, too. The position of this radius is determined by the angle P_R between radius R and the line OιO₂ connecting centres of the rotors. The size of the analogous angle of the rotor 4 is the same, too.

When angles α and β grow smaller, the radius of the rotor 4 remains the same, and, in the position where the tips of the rotors meet, the radius of the rotor 5 changes from p=R to p=A-R (fig.7). From fig.7 it is visible that pi of a certain length and the angle βi determining its position depend each on the angle ctj. When coming to the position Otj, the rotor 4 forms an angle Δα=α_R-αs. The rotor 5 comes to the position where the tips of the rotors meet after this rotor forms an angle 2Δα since the rotation speed of this rotor is twice as greater. Therefore, after increasing, against the rotation direction the angle βi by adding to it the angle 2Δα, we shall have the position pi on the surface of the rotor 5 from which this rotor comes to the position where the tips of the rotors meet, this position being determined by angles Ot; and β;. The angle 2OC_R from the line OιO₂ ( =0, β=0) determines where the surface of the rotor 5 passes to a constant curvature with the radius p=A-R. For carrying out the rotor 5 it is more convenient to have the formula for the calculation of the variable curvature surfaces. In the system of polar co-ordinates, the radius - vector p and the polar angle φ may be put in the following way:

φ_rβ_R- (2α_R_ β.)

β_R = arct_gΛ/(2R/A)² -1 sinα, βi = arctg

A/R - cosα. The rotary internal combustion engine operates n the following manner. After the rotors 4 and 5 move from the full-contact position, the compressed air-fuel mixture is ignited with the sparkle cast by the plug 9. The heat of the burnt fuel raises the pressure of the working agent under influence of which the rotors give out the mechanical work to the shafts 6 and 7. After the expansion of the working agent, scavenging air is drawn through the channels 10 and 11. When combustion products are evacuated, the drawing of the air is stopped and a fuel portion is sprayed into the air that is present in the working chamber, while the obtained mixture is transferred to the pressure chamber 12 through the surfaces of the spinning rotors 4 and 5. Afterwards, the working cycle of the engine is repeated. If, in the case of a carburettor engine, the degree of the pressure in the full-contact position is too great, it can be reduced by deepening the cavity or by making a cavity on the lobe.

In the case of a diesel engine, instead of an ignition plug, a fuel jet is foreseen which draws the fuel into the compressed heated air the high temperature of which causes a self inflammation.

The indicator of the power of rotary internal combustion engines may be the ratio of the chord determining the width of the lobe of the male rotor with the distance between the axes of the rotors. In the case of the prototype it is indicated as C_R=0,33-0,55. In the present engine this ratio approaches to 1. The power of the engine may be increased by mounting several pairs of rotors on the same shafts. Since a male rotor with a single lobe requires equiblirating means, a relevant location of several rotors on one shaft as indicated in fig.5 simplifies the solution of this task. In addition, the power of the engine may be increased by making a set of one female rotor with cavities and two male rotors with lobes (fig.6).

Claims

1. The rotary internal combustion engine having a casing with two parallel cylindrical chambers (2, 3), two parallel shafts (6, 7), connected by a synchronising cogged gear (8), and having female and male rotors mounted on them and mutually intermeshing by cavities and lobes of their flank surface, characterised in that the female rotor (4) has two cavities, and the male rotor (5) has one lobe.

2. The rotary internal combustion engine in accordance to Claim 1, characterised in that in the casing there is foreseen an ignition plug (9), located near the edge of the cavity of the female rotor(4), when the edge is leaving the full-contact position with the lobe of the male rotor (5).

3. The rotary internal combustion engine in accordance to Claim 1 and 2, characterised in that there are more than one pair of rotors, mounted on the same shafts with a different location of the lobe with regard to the circle of the shaft.

4. The rotary internal combustion engine in accordance to Claims 1-3, characterised in that the female rotor (4) with cavities is intermeshed with the lobes of two male rotors (5) that are present on the shafts parallel to the shaft of the female rotor (4) having cavities.