WO2007028487A1

WO2007028487A1 - Rotary internal combustion engine

Info

Publication number: WO2007028487A1
Application number: PCT/EP2006/008122
Authority: WO
Inventors: Klaus Teichert; Elmar Grandy
Original assignee: Klaus Teichert; Elmar Grandy
Priority date: 2005-09-07
Filing date: 2006-08-17
Publication date: 2007-03-15
Also published as: DE202005014109U1

Abstract

The invention relates to a rotary internal combustion engine (1) having a chamber, two pistons (3, 4) which are arranged in the chamber and an output shaft (5), wherein it is proposed that the chamber is of rotationally symmetrical and annularly closed configuration and the pistons (3, 4) are arranged in a circular segment-shaped manner on a common circular path in the chamber, with the result that combustion chambers (6, 7) are formed between the pistons (3, 4). The pistons (3, 4) are connected releasably to the output shaft (5), with the result that a gas which expands in one of the combustion chambers (6, 7) drives the output shaft (5).

Description

DESCRIPTION

Rotary engine

The invention relates to a rotary internal combustion engine according to the preamble of claim 1.

Rotary combustion engines are known from the prior art in various embodiments. They differ from reciprocating internal combustion engines by the advantage that no power must be transmitted from a translational movement of the reciprocating piston to an output shaft. The best known rotary internal combustion engine is the Wankel engine, in which a rotary piston is arranged on an eccentric shaft. The rotary piston has at its periphery three flattened circular arc, so that in the chamber in which moves the rotary piston, three combustion chambers are formed. Furthermore, rotary internal combustion engines with two intermeshing rotating pistons are known, which are arranged in a chamber, see for example German Offenlegungsschrift 2 057 475.

A disadvantage of the previously known rotary internal combustion engines is that the sealing of the combustion chamber is problematic, whereby the production is more expensive. Furthermore, the Wankel engine, the elongated combustion chamber is disadvantageous because it can lead to incomplete or poor combustion and has a high heat output. The non-uniform shape of the combustion chambers also represents a disadvantage of rotary internal combustion engines with two rotary pistons. The object of the invention is to provide a rotary internal combustion engine, which overcomes the disadvantages of the prior art and in particular allows for a simple construction improved combustion.

The object is achieved with a rotary internal combustion engine according to claim 1.

The invention improves the shape of the combustion chamber by a chamber in which there are two pistons, is formed rotationally symmetrical and annularly closed, wherein the pistons are arranged in a circle segment in the chamber in the rotational direction one behind the other. As a result, combustion chambers, which are similar to the combustion chambers of a reciprocating internal combustion engine but are curved in the radius of the annularly closed chamber, are formed between the pistons. Furthermore, this arrangement has the advantage that the sealing of the combustion chambers is improved, since the combustion chambers are not sealed with a narrow material lip as in the Wankel engine, but, as in a reciprocating engine, by a section of the circular-segment-shaped pistons.

For power transmission, the pistons are connected according to the invention to an output shaft, wherein the connection is rotationally fixed in the direction of rotation of the piston driven by a propagating gas. In this way it is achieved that the propagating gas acts on the output shaft via the piston.

Preferably, the rotary engine has two pistons, each forming a 120 ° comprehensive circle segment. Accordingly, the two combustion chambers formed in each case occupy a maximum of 120 ° of the full circle. The invention is not limited to the arrangement of two kreisseg- mentförmigen piston, but more than two pistons can be arranged in the annular chamber, so that more than two combustion chambers are formed. The output shaft may be embodied as a shaft located within the annular chamber, but it is also conceivable that the output shaft is a hollow shaft which is arranged around the annular chamber. Furthermore, it is also conceivable that the output shaft, as in a simple shaft coupling on one side of the annular chamber in the form of a ring or a disc axially adjacent to the chamber. The pistons, which are arranged so as to be rotatable independently of one another in the chamber, can be guided through a centrally arranged bearing, in which case a connection has to be arranged between the pistons and the centrally arranged bearing. It is also possible to arrange the pistons in the annular chamber without further pivotal mounting, so that the pistons can slip in a circular manner in the chamber. Another possibility is to equip the pistons or chamber with surface mounted roller bearings. The pistons advantageously fill the chamber only to the circumferentially outer peripheral surfaces, which constitute the boundary surfaces to the combustion chambers, completely to seal the combustion chambers. Between the two boundary surfaces, a piston can be designed in any way, for example, to provide opportunities for power transmission, power transmission or for a hydraulic connection.

The rotary internal combustion engine according to the invention is preferably operated in a 2- or in a 4-stroke cycle. To this end, air, fuel or mixture inlets and corresponding outlets are to be provided at a suitable point in the chamber. The processes in a combustion chamber correspond to the cycles of a 2-stroke-operated or 4-stroke-operated Reciprocating internal combustion engine. Furthermore, with a suitable adaptation of the rotary internal combustion engine, operation with different fuels is possible, for example petrol, diesel fuel, natural gas or hydrogen. When operating with hydrogen, however, it must be taken into account that the lower heat output of the curved, but compact combustion chambers, which is advantageous over the Wankel engine, must be taken into account when operating with hydrogen in order to prevent premature mixture ignition.

By designing the boundary surfaces of the pistons, the shape of the combustion chamber can be adapted to the ignition timing. Preference is given to a substantially lenticular combustion chamber, wherein the boundary surfaces are each curved inwardly with respect to the piston. A filament or a glow plug may be attached at a suitable location, mounting on the wall of the chamber or on one of the boundary surfaces.

For connecting the output shaft to the piston, an output clutch is preferably provided. The output coupling connects the piston with the output shaft in the direction of rotation of the piston torsionally rigid and detachable. The output clutch is preferably designed to be controllable, so that the torsionally rigid connection between the output shaft and the respective piston can be controllably locked and released. Preferably, each piston is releasably connected via an output coupling with the output shaft.

An advantageous embodiment of the invention has an abutment, wherein the pistons are independently releasably connectable to the abutment. In conjunction with the detachable connection of the pistons with the output shaft, a piston can be arrested on the abutment in this way. connect a further piston with the output shaft, so that a mixture ignited in the combustion chamber between the two pistons during propagation is supported against the piston connected to the abutment and drives the piston connected to the output shaft, so that a torque is transmitted to the output shaft. Due to the releasable connections of the pistons with the abutment and the output shaft, the blowing of the burned mixture, the intake of air or mixture and the compression can be organized by the pistons in timed sequence with each in a 4-stroke operation of the rotary internal combustion engine be connected to the abutment or the output shaft.

Advantageously, an abutment clutch is arranged between the abutment and one of the pistons. It is preferred if an abutment clutch is arranged between each of the pistons and the abutment.

The abutment itself is preferably rigidly connected to a housing block surrounding the rotary internal combustion engine and, similar to the output shaft, can be designed in different ways. For example, it is possible to arrange the abutment as a rigid inner shaft on the symmetry axis of the rotationally symmetric chamber. Furthermore is also a

Arrangement on the outside of the chamber possible, for example in the form of a circumferential ring, or an arrangement laterally adjacent to the chamber, similar to a disc clutch.

Advantageously, the abutment clutch and / or the output clutch are spatially separated from the interior of the chamber. This offers the advantage that the clutches are not exposed to the high temperatures of the combustion processes. An advantageous possibility is the couplings of to separate the piston, characterized in that the pistons are rigidly connected to circulating around the chamber rings, which can be accessed from the outside with coupling elements. Suitable coupling elements are, for example, controllable pins, clamping couplings, tooth engagements and other possibilities known to the person skilled in the art, this generally applying to internal or external output and abutment couplings. The rigidly connected to the piston ring can also be arranged inside. This offers the advantage that the size of the rotary internal combustion engine can be kept within limits with the radius of the annular chamber maximized.

Preference is given to an abutment clutch or an output clutch, which operate automatically, for example by being equipped with a detent which is pressed by a spring into a detent position. By arranging a driven catch and an abutment button acting in opposite directions, it is possible to perform the locking and the connection of the segments with the output shaft or the abutment completely automatically.

The rotary internal combustion engine according to the invention can be used in motor vehicles, aircraft or ships. Even a stationary operation is possible.

An independent subject of the invention is a drive train, in particular a drive train for a vehicle, which has a rotary internal combustion engine in one of the advantageous embodiments. The drive train according to the invention additionally has an electric machine. Preferably, the electric machine is a generator or an electric motor. Particularly preferred is an electric machine that can be operated as a generator and as a motor. This offers the advantage that a Hyb Rid drive with brake energy recirculation is possible. The rotary internal combustion engine and the electric machine preferably act on the same output shaft. In general, it is preferred that a plurality of rotary internal combustion engines are arranged in one of the aforementioned embodiments on a drive train in order to compensate for the imbalance of the individual rotary internal combustion engines. Another way to compensate for the imbalance of the rotary internal combustion engine, outside the chamber further segments to be arranged, which are each rigidly connected to a rotating piston in the chamber.

The invention will be explained in more detail with reference to the accompanying drawings, which show an exemplary embodiments of the invention düng.

FIG. 1 shows a schematic sectional view of an embodiment of the rotary internal combustion engine according to the invention.

FIGS. 2A-2C show the operation of the rotary internal combustion engine of FIG. 1.

FIG. 3 schematically shows an exemplary drive train according to the invention.

FIG. 1 shows a rotary internal combustion engine 1 according to the invention in a sectional view. A housing 2 surrounds from the outside an annular chamber in which a first piston 3 and a second piston 4 are arranged. The chamber in which the pistons 3 and 4 are arranged, is bounded inwardly by an output shaft 5, wherein the chamber has a rotationally symmetrical shape. The pistons 3 and 4 are basically independent of each other and freely movable in the chamber, wherein they follow the course of the chamber due to their circular segment-like shape in their movement, so that they perform a rotational movement about the centrally arranged output shaft 5. Between the two pistons 3 and 4, a first combustion chamber 6 and a second combustion chamber 7 are formed, which are delimited by boundary surfaces 10 of the pistons 3 and 4 in the radial direction.

The general direction of rotation of the output shaft 5 is directed in the illustration in Figure 1 counterclockwise. In order to transmit torque from the pistons 3 and 4 to the output shaft 5, drive cams 15 and 16 are arranged on the pistons 3 and 4, respectively. The drive cams 15 and 16 have a latch-like shape and engage in latching positions 20 of the output shaft 5, wherein the drive cams 15 and 16 are each pressed by a spring 17 and 18 in the latching positions 20.

The rotary internal combustion engine 1 shown in Figure 1 is shown in a position in which the pistons 3 and 4 in the sectional view above close to each other, wherein in the intermediate combustion chamber 6 at this time, an air-fuel mixture is ignited. The output shaft 5 is driven via the second piston 4 and the driving cam 16. As a support for the expanding exploding

Mixture serves the first piston 3, which is supported against the housing 2 via an abutment pad 25. The housing 2 thus serves as an abutment for the explosion in the first combustion chamber 6. The abutment cam 25 is pressed by an abutment spring 26 into a detent position 31 of the first piston 3. In the housing 2, two further abutment cams 27 and 29 are arranged, which are pressed by abutment springs 28 and 30 inwards. The abutment cams 25, 27 and 29 are arranged offset in the housing 2 by 120 °, so that the pistons 3 and 4, which also each occupy an angle of 120 °, can serve at three positions as an abutment for an explosion in one of the combustion chambers 6 or 7. In the position shown in FIG. 1, the second piston 4 is not held by the abutment cam 27, since the second piston 4 is pressed counterclockwise by the explosion in the first combustion chamber 6, with the abutment cam 27 pressed against its spring 28 and thus clears the way for the second piston 4.

Mixture inlet openings 35 are arranged on the rear wall of the rotary internal combustion engine 1 lying below the plane of the drawing, wherein only the mixture inlet openings 35 located in the region of the second combustion chamber 7 can be seen, since the other mixture inlet openings are covered by the pistons 3 and 4. At the lying above the plane of the drawing, not shown wall of the chamber of the rotary internal combustion engine 1 Gemischauslassöffnungen are arranged. At the time of operation shown mixture is injected through the mixture inlet openings 35 mixture under pressure in the second combustion chamber 7, wherein the burned mixture of the last power stroke of the rotary internal combustion engine 1 is pushed out by the overhead, not shown Gemischauslassöffnungen. To generate pressure, the mixture is passed through a compressor connected to the output shaft before it enters one of the combustion chambers 6 and 7. The rotary internal combustion engine 1 is accordingly operated in 2-stroke operation and flushed with a DC purge. Other rinsing methods are known to the person skilled in the art and can also be used. For example, a crossflow purge or a Schnürle reverse purge may be used, with the mixture inlet ports and the mixture outlet ports to be arranged accordingly. In the following description of Figures 2A to 2C and 3, the same reference numerals are used for the same parts, wherein in Figures 2A to 2C, the rotary internal combustion engine 1 shown schematically in Figure 1 is shown in each case in a different working position. For better clarity of Figures 2A to 2C and 3, some reference numerals are omitted in these figures.

In FIG. 2A, the internal combustion engine is again shown in the position shown in FIG. 1, this being the position at the beginning of the first cycle of the operation of the rotary internal combustion engine 1. In the first combustion chamber 6 takes place at this time, the ignition of a mixture, whereas the second combustion chamber 7 is purged. For rinsing, mixture is injected under pressure through the mixture inlet openings 35, wherein burnt mixture of the last explosion in the second combustion chamber 7 is ejected through the mixture outlet openings (not shown). Due to the explosion in the first combustion chamber 6, the piston 4 is rotated counterclockwise, wherein it drives the output shaft 5. The first piston 3 serves as a support or abutment for the spreading mixture.

In FIG. 2B, the rotary internal combustion engine 1 is shown in a state during the first power stroke, wherein the propagating mixture in the first combustion chamber 6 has already rotated the second piston 4 by approximately 70 ° in the counterclockwise direction. Due to the rotating second piston 4, the still unburned mixture in the other, second combustion chamber 7 is compressed due to the first piston 3 fixed at this time.

In FIG. 2C, the rotary internal combustion engine 1 is at the end of the first power stroke and at the beginning of the second power stroke. Beitstaktes shown, wherein the beginning of the second power stroke is characterized by the explosion of the present in the second combustion chamber 7 mixture. The second piston 4 has rotated counterclockwise by 120 ° relative to the position shown in FIG. 2A, the mixture located in the second combustion chamber 7 having been completely compressed. The first combustion chamber 6 has now taken its largest possible volume and is flushed at this time. This means that fresh mixture is injected under pressure into the first combustion space 6 through the now lying in the region of the first combustion chamber 6 mixture inlet openings 35 and burned mixture is discharged through the mixture outlet not shown.

As a result of the explosion in the second combustion chamber 7 at the beginning of the second power stroke, the first piston 3 is moved, with the second piston 4 now acting as an abutment. About the first piston 3, the output shaft 5 is rotated further, so that it comes to a continuous drive of the output shaft 5. The rest of the second cycle of the rotary internal combustion engine 1 proceeds analogously to the illustrated first cycle, wherein in the first combustion chamber 6, the fresh mixture located there is compressed. During the second power stroke, the first piston 3 moves counterclockwise, whereas the second piston 4 remains in its position.

In the example shown, the rotary internal combustion engine is operated with a two-stroke process, by slight changes in the rotary internal combustion engine 1, for example, by providing controllable output and abutment couplings for the pistons 3 and 4, a 4-stroke operation is also possible. Advantageously, for a 4-stroke operation, two or more of the illustrated rotary internal combustion engines 1 arranged on an output shaft, so that it comes to a very uniform drive of the output shaft.

FIG. 3 shows a drive train which is particularly suitable for use in a vehicle and which has a total of three rotary internal combustion engines 1. The rotary internal combustion engines 1 are constructed according to the embodiment shown in the figure 1 and arranged together on an output shaft 5. Between the rotary internal combustion engines 1 electrical machines 40 are each arranged between two rotary internal combustion engines 1, which are connected to the transmission of torques to the output shaft 5. With the electric machines 40, a drive of the output shaft 5 is possible, even if the rotary internal combustion engines 1 are not operated, since the rotary internal combustion engines 1 due to their construction with the driving cams 15 and 16 have a freewheel. If the torque provided by the rotary internal combustion engine 1 on the output shaft 5 is above the required torque of the output shaft 5, the electric machines may be used as generators, for example, to charge a battery with which the electric machines 40 are driven at a different time can be.

The invention is not limited to the preferred embodiments described above. Rather, a variety of variants and modifications within the scope of the invention is possible.

Claims

A rotary internal combustion engine (1) which comprises: a) a chamber, b) two pistons (3, 4) arranged in the chamber, and c) an output shaft (5), characterized in that d) the chamber is rotationally symmetrical and annularly closed is, e) the pistons (3, 4) are circular segment-shaped and are rotatably arranged on a common circular path in the chamber independently of each other, so that between the piston (3, 4) combustion chambers (6,7) are formed, and f) the Pistons (3, 4) are independent of each other with the output shaft (5) releasably connected and rotationally fixed in at least one direction of rotation such that in one of the combustion chambers (6.7) propagating gas drives the Ab- drive shaft (5).

2. rotary internal combustion engine (1) according to claim 1, characterized in that between the output shaft (5) and one of the piston (3, 4) an output coupling (15, 16) is arranged.

3. rotary internal combustion engine (1) according to any one of the preceding claims, characterized by an abutment (2), wherein the pistons (3, 4) independently of each other with the abutment (2) releasably connected and rotationally rigidly connected in at least one direction of rotation, so that the piston (3, 4) connected to the abutment (2) forms a resistance to the propagating gas.

4. rotary internal combustion engine (1) according to claim 3, characterized in that between the abutment (2) and one of the piston (3, 4) an abutment clutch (25, 27, 29) is arranged.

5. rotary internal combustion engine (1) according to one of claims 2 to 4, characterized in that the abutment clutch (25, 27, 29) and / or the output coupling (15, 16) by a catch (15, 16, 25, 27, 29 ) is formed, which is pressed by a spring (17, 18, 26, 28, 30) in a latching position (20).

6. powertrain, in particular for a vehicle, with a rotary internal combustion engine (1) according to one of claims 1 to 5 and an electric machine (40).