DE2452449A1 - Two-stroke rotary piston engine - piston revolves opposite to crankshaft to give four working strokes each revolution - Google Patents

Abstract

The engine consists of a cylindrical housing open at one end to form a chamber containing two segment shaped distance pieces with flat side and base surfaces. The distance pieces side walls have curved sealing surfaces which make sliding contact with the inner surface of the cylindrical housing. The two segments, together with the outer housing end wall form a rectangular cylinder boring with an exhaust collection channel able to receive a rotating rectangular piston provided with sealing strips. The piston divides the chamber into two combustion chambers, whereby the fuel is alternatively ignited on the two face sides of the piston.

Description

The invention relates to and relates to rotary piston engines in particular rotary piston internal combustion engines,

Ever since steam and internal combustion engines began to be built, the Efforts to construct such machines with back and forth outgoing piston. In the course of time, however, it became increasingly clear that machines with reciprocating pistons were based on build on a false principle that these pistons begin to move from a rest or dead position within a very short time Accelerate time to maximum speed and then decelerate again to a new complete rest or dead position. This constant starting and stopping of the pistons causes numerous difficult ones, especially at higher speeds Problems, which is why one began early, the machines with reciprocating pistons by working rotary piston machines substitute. This development began with steam engines and is now almost complete. Steam turbines have been developed have been used in almost all practical applications, Especially in larger systems, machines with reciprocating pistons have taken the place of machines.

This development process has proven itself in internal combustion engines than more difficult. Although the correctness of the rotary piston principle has also been recognized for internal combustion engines, the solution has proven itself practical problems have been shown to be so difficult that there are still no existing, completely successful

609820/0474

piston internal combustion engine can be spoken. The effort we are, however, trying hard to continue in this direction.

An object of the present invention is to provide an improved To create rotary piston internal combustion engine in which many of the Difficulties and problems with which previous designs are afflicted, overcome and largely eliminated and which has numerous advantages in practical application »The machine according to the invention should be quiet and without sudden Starting and stopping the pistons, connecting rods and others; -? Parts run.

The aim of the invention is in particular to provide an improved rotary piston internal combustion engine in which twice as many power strokes per revolution occur as with conventional ones Machines, so that a smoother and quieter run is achieved.

Furthermore, the machine according to the invention should have smaller dimensions and have a lower weight per generated power than internal combustion engines reciprocating pistons and conventional rotary piston internal combustion engines.

Another object of the invention is to provide an improved To create rotary piston internal combustion engine in which the problem the sealing of their parts working under pressure is considerably lower.

It is also among the objects of the invention to provide a rotary piston internal combustion engine to create that has simple ignition and combustion systems with conventional individual parts. Included the removal of the exhaust gases should be quick and easy. Furthermore, the rotary piston internal combustion engine according to the invention should be without difficult machining problems with which conventional rotary piston internal combustion engines are afflicted can be produced.

Another object of the invention is to provide an improved rotary piston internal combustion engine in which the same Distances beyond the scope of the machine's work performance

60982 0/0474 BADORiGJNAL

impulses occur, therefore the machine structure is uniform warmed up and allowed for even cooling.

It is also among the objects of the invention to provide an improved rotary piston internal combustion engine in which the working and The discharge stroke is completed in a much shorter time than in conventional machines, so that nitrogen oxides are practically nonexistent Opportunity to arise and, after ejecting eggs, to pollution to contribute to the atmosphere.

As a result of the uniform distribution of the power pulses over the circumference, the rotary piston internal combustion engine according to the invention permits also the use of a larger number of spark plugs, whereby the load on the individual candles is reduced to a minimum.

The invention is more preferred in the writing below Embodiments based on the drawing. cn explained in more detail. Show in the drawings

Fig. 1 is a disassembled perspective; Representation of a Implementation example of the erfi. according to the machine;

2 shows a plan view of a machine according to the invention;

Fig. 3 is a plan view of the in c ^; r machine according to Fig. used exhaust gas collector it; .. ^;

Fig. 4 is a longitudinal section through a. Embodiment of a machine according to the invention;

Figure 5 is a cross-section along line 5-5 of Figure 4; FIG. 6 shows a section along the line "6-6 according to FIG. 5;

FIG. 7 shows an enlarged illustration of the underside of the exhaust gas collecting line according to FIG. 2, the arrangement the outlet openings is shown;

8 shows a perspective illustration of one of the segment-shaped spacer elements as shown in FIG an embodiment of the invention can be used;

9 shows a perspective illustration of one in one Embodiment of the invention used piston;

10 shows a cross section through an exemplary embodiment

6098 ^ 0/00 /, BADOfflSINAL

the machine according to the invention, the piston in the starting position of a Rotation is shown;

11-21 the individual positions which the piston in the embodiment according to Fig. 10 runs through during one revolution of the machine;

22 shows a partial longitudinal section through an exemplary embodiment the invention with two pistons and eight working strokes per machine revolution;

FIG. 23 is an illustration of a servo or driven one used in the machine of FIG Piston with slots for receiving lugs on the counter shaft driving the piston the machine;

Figure 24 is a cross-sectional view taken along line 24-24 of Figure 22; and

25 shows a partial illustration of an exemplary embodiment of the invention with a modified spacer element Construction.

It should first be noted that the invention in their application to the details of construction and arrangements of their various shown in the drawings Parts limited, but other embodiments is capable. The terminology used in the following description is also used for explanation purposes, without limiting the scope of protection to restrict.

Furthermore, the present invention is not limited to one type of rotary piston machine, but is with many Machine types applicable, such as diesel engines, two-stroke and four-stroke gasoline engines and even piston-less machines, if the crankshaft rotates in the opposite direction to the power-generating parts. Furthermore, it is not only possible to provide multiple pistons in a combustion chamber; additional combustion chambers and piston arrangements can also be used without further ado

609820/0/4 74

2452 * 49

Arrange them in rows along the crankshaft to increase the output power to increase "

Further, when the descriptions in the following machine externally driven via the crankshaft and in such a way controlled via the openings and the valve, that a liquid enters the chambers and is discharged from this, so it can be operated as a pump, the same pulses over its circumference ( with the resulting uniform flow), as when working strokes occur when used as a motor.

For a simpler explanation, the invention is based on the following a two-stroke rotary piston internal combustion engine in their execution described with one and with two pistons. It is emphasized that the invention does not relate to one or two pistons for power Transfer limited, but provided with any working number of pistons, for example four or even five pistons can be.

1 to 9, a generally designated 10 is circular Housing provided at one end with a cylindrical chamber 11 open on one side, which has an inner jacket surface and has a planar inner end wall 18. In chamber 11 two segment-shaped spacer elements 15 are arranged, each have a flat bottom surface 17 and side walls 19. On each side wall 19 of the spacer elements 15 are arcuate Sealing surfaces 16 are provided which are in sliding contact with the inner jacket surface 12 of the chamber 11.

As can be seen, the bottom surfaces 17 form the two spacer elements 15 together with the end wall 18 of the chamber 11 and one inner wall 21 of an exhaust manifold 22 in the assembled State of a rectangular cylinder bore, in which a generally designated 23 piston, which has an upper end face 24 and a has lower end face 25, can be slidably fitted.

A pair of interlocking L-shaped spacers 28 are used to seal the piston within the cylinder bore

609870 / 0A 74

and 28a are provided with a rectangular cross section, each of which is arranged in the respective one on the two end faces of the piston 23 rectangular grooves 29 or 30 fit. The L-shaped spacers 28 and 28a are outwardly against the walls the combustion chamber pressed by corrugated spring strips 31, which between the piston 23 and the spacers 28, 28a are inserted. The piston 23 has a narrower central section 33 in which a slot 34 for receiving the crank pin 35 of a crankshaft 36 is arranged.

In Fig. 25 is a modified embodiment for the spacer elements 15 shows the indentations on their bottom surface 17 for better positive engagement with lugs 45 and 46 have a countershaft.

In the construction described above, the initially one-piece combustion chamber by the piston 23 is effectively divided into two combustion chambers divided, the fuel in each of these combustion chambers can be ignited. As explained below, will in the present embodiment, the fuel ignited alternately at the two end faces of the piston 23, whereby a Back and forth movement of the piston between the flat bottom surfaces 17 of the segment-shaped spacer elements 15 is caused. If the piston moves back and forth in this way, it takes the crank pin 35 of the crankshaft 36 with it and thereby displaces it the crankshaft in rotation. Due to the peculiar design, the piston rotates around the crank pin at the same time and thereby sets the spacer elements 15 and the two combustion chambers in rotation.

In conventional rotary piston machines, the piston and the combustion chamber rotate in the same direction as the crankshaft, which necessarily limits the machine to one working stroke of the piston per rotation of 180. For a two-stroke rotary engine with only one intake and compression stroke and one work and discharge stroke, this means that even with Use of both sides of the piston and alternating ignition of the gas mixture on both sides of only two working strokes

6 0 9 8 2 0 / () λ 1 h

-7- 2452U9

can be achieved per revolution.

According to the invention, on the other hand, the piston and combustion chamber rotate necessarily in the opposite direction as the crankshaft. As a result of the mechanical advantage achieved in this way, for a working stroke of the piston only requires a rotation of the crankshaft by 90 ° instead of the previous 180 °. This means that twice as many working strokes can be achieved per revolution of the machine. In the case of a two-stroke rotary engine this results in four working strokes per revolution, which essentially halves the power-to-weight ratio of the machine, For a given machine performance, smaller dimensions and numerous further operational advantages can be achieved. The advantage of smaller dimensions is in itself because of the considerable Concerns about air pollution caused by modern reciprocating piston internal combustion engines exist, of very great importance. A machine with smaller dimensions leaves more space in the engine compartment for all those facilities that are used to reduce the exhaust gases that inevitably occur in all internal combustion engines is needed.

Furthermore, since the nitrogen oxides are the most difficult to dispose of and are only produced as long as the combustion products are are kept within the combustion chamber during the working stroke, the amount of nitrogen oxides generated is correspondingly reduced by reducing the time for the working stroke by half reduced by 50%.

To ensure that the crankshaft rotates in the opposite direction to the piston and combustion chamber, this is close to that Crank pin 35 opposite end of the crankshaft Bevel gear 37 is arranged. This bevel gear drives a pair of intermediate gears 38 and 39 and a further bevel gear 43 Countershaft 40, the bevel gear 43 being attached to one end of the countershaft 40. The countershaft 40 is outside the Crankshaft 36 is supported in bearings 44 and in housing 10 held by bearings 44a. At the end opposite the bevel gear 43, the countershaft 40 has the two lugs 45

e η ρ 8? η / ο a 7 / *

2452U9

and 46, which are in contact with the flat bottom surfaces 17 of the spacer elements 15.

With this structure, if the crankshaft 36 rotates in a direction so are on the bevel gear 37, the intermediate gears 38 and 39 and the bevel gear 43 the countershaft 40 with its lugs 45 and 46 and thus the spacer elements 15 are driven in the opposite direction. This ensures that the Crankshaft 36 rotates opposite to piston 23.

The one in this opposite rotation of the piston and crankshaft The advantage is best shown with reference to Figs. 10-21, wherein the various stages of operation of the Machine are shown within one revolution of the crankshaft.

Fig. 10 shows the piston generally designated 47, one end face 48 of which is at the top of its intake and compression stroke is approximately at the time the first spark plug 49 fires. At this point in time is located the other end face 55 of the piston 47 at the beginning of their approach and compression stroke after all exhaust gases are expelled through outlet port 41 and fresh fuel mixture through an inlet port 42 has been sucked in.

Due to the structure explained above, the piston begins to move according to FIG. 11 with its working and exhaust strokes to move down and at the same time turn counterclockwise, while the now designated 50 crank pin starts rotating clockwise. By the piston 47 moving further downward within its stroke according to FIG. 12, an outlet opening 43 is partially exposed, so that the exhaust gases begin to escape. At the time when the piston 47 according to Fig. 13 ends its stroke, its end face 48 is at right angles to the position at the beginning of the stroke, and the outlet opening 53 and an insert opening 54 are completely free.

In an actual embodiment of the invention, the

6 0 9 8 2 0/0 I, 7 h

The outlet port 53 and the inlet port 54 are provided on opposite sides of the piston 47, since the outlet ports according to FIG 7 are arranged in the exhaust gas manifold 22. For ease of explanation and illustration, however, FIGS. 10 to 21 the inlet and outlet ports are shown on the same side of the piston. Incidentally, the exhaust manifold 22 has one with the Outlet ports 41, 53, 58 and 62 · communicating outlet 26.

As the fuel-air mixture is drawn into the combustion chamber through inlet port 54, it pushes the remaining exhaust gases out through the outlet opening 53, whereupon the end face 43 of the piston 47 is ready to close with the induction compression stroke kick off. The other face is at the same time as this process 55 of the piston ends its intake / compression stroke, and the compressed air-fuel mixture is passed through the second Spark plug 51 ignited so that the end face 55 of the piston 47 is opposite to its previous direction of movement begins to move, while the rotation of the piston in a counterclockwise direction and the rotation of the crankshaft continues in an ir.clockwise direction will.

Upon further rotation of the piston by a further 90 °, the inlet and outlet openings at 48 are shown in FIGS. 14 to 16 Front side of the piston 47 with the completion of the suction-compression stroke closed (Fig. 14 and 15) and the outlet opening 58 and an inlet opening 59 on the other end face 55 of the piston is opened, whereby the working and exhaust stroke of this piston side 55 is ended.

At this point in time, according to FIG. 16, the third spark plug 56 ignites, whereby the second working and exhaust stroke of the other end face 48 of the piston 47 is started within this revolution. As the piston continues to rotate, the outlet ports 58 and the inlet opening 59 on the upper side of the machine according to FIGS. 17 and 18 is closed, the end face 55 of the piston 47 their intake and compression stroke ended and, as shown in FIG. 19, the fourth spark plug 60 ignites so that the end face 55 with the second working and exhaust stroke begins within this revolution.

609820/0474

Meanwhile, an inlet port 61 and the outlet port 62 on the right side of the engine have been released so that the face 48 of the piston 47 begins another intake and compression stroke and returns to the top of the machine. This completes one complete revolution of the machine.

As can be seen from the above explanations, v / ground at every revolution the machine achieved a total of four working strokes or power pulses by alternately turning on both sides of the piston is ignited after each rotation of 90, while in all conventional rotary piston machines in which turn the crankshaft and the piston in the same direction, at best ignition is achieved every 180 °.

During actual operation of the machine, the air according to FIG. 2 is passed through an air cleaner or an air cleaner by means of a fan 67 Filter 65 and a carburetor 66 accumulated. The fan 67 is 4 driven by the intermediate gear 39. After passing through the fan 67, the air enters an intake manifold 68, from v / o it enters the combustion chamber through the various inlet openings.

To accurately meet the engine's fuel-air requirements, the capacity of the fan is designed to be larger than the machine requires, and to change the amount of air supplied a bypass valve 69 is provided according to FIG. By adjusting the bypass valve 69, it is possible to meet the machine requirements to meet exactly, so that not in the purge cycle unburned fuel directly through the chamber and through the Outlet is blown. For the same reason, a baffle 57 is also provided on both sides of the piston.

As the engine speed increases, the time during which the openings are open is proportionally reduced, and the pressure to the Loading the cylinder must be increased accordingly. To achieve such a pressure increase, valve 69 is as well the carburetor is coupled to the accelerator pedal via a connection 70.

6 0 9 8 7 0/047 / *

If the pressure on the valve 69 is increased via the connection 70, the air pressure in the intake manifold 68 increases, and the pressure in the The amount of air introduced into the combustion chamber increases.

To ignite the fuel-air mixture at the right time Bringing about in the combustion chamber is a manifold provided, which is driven via a distributor gear 74 provided on the crankshaft 36. This distributor can be more conventional Be designed as in internal combustion engines with reciprocating pistons and in a similar way for igniting the fuel-air mixture controlled at the right time. The distributor is connected to the spark plugs via suitable ignition lines 75 49, 51, 56 and 60 connected. The other elements of the conventional ignition system used here, including the ignition coil, a battery and other important parts are not shown because they are known and no special description need.

Cooling of the machine can be accomplished by any conventional means using water or air. By doing The illustrated embodiment of the invention is an air-cooled version for the rotary piston internal combustion engine according to the invention has been chosen. In the present case, the air cooling is achieved in that on the outside of the chamber 11 on the circumference radially extending cooling fins are provided. A part of these cooling fins 76 can be seen in FIG. 4.

22 to 24, there is another embodiment of the present one Invention shown with two pistons that move back and forth in a rotating combustion chamber while eight Execute working strokes per revolution.

The two pistons are each generally designated 79, have an upper end face 80 and a lower end face 81 and are similar to the single piston used in the exemplary embodiment explained above. Each piston has a narrow central section 82 with a centrally arranged slot 83 for receiving the crank pin 84 of a crankshaft 85. Due to the narrow middle section, the two pistons 79 can right-

609820/0 /, 74

2452 * 49

moving angle to one another in the combustion chambers to and fro, which limits \ tortenstück- or by a plurality of sector-shaped spacer elements 88 irerden _e The spacer elements 88 form together with the walls of the circular chamber 89 and the piston 79, four separate combustion chambers.

Each piston also has a groove 90 with a rectangular cross-section for receiving L-shaped spacer elements on each end face 91, which also have a rectangular cross-section and press against the walls of the combustion chambers in order to be similar to the previously described embodiment to effect a seal.

However, since it is not expedient to individually drive the sector-shaped spacer elements 88 to rotate the pistons 79 opposite to the crankshaft 85, that piston 79, the narrow central section 82 of which is on the rear side of the machine, has two slots 92 for receiving on the counter shaft 9h provided drive pin 93 and is thus driven directly against the direction of rotation of the crankshaft 85.

As can be seen, in this embodiment of the invention the piston 79 has a straight inclined section 95 on its two end faces 80 and 81. This sloping section carries contributes to the fact that the machine continues to turn in the correct direction and that upon ignition of the fuel-air mixture, a force is directed in such a way that this rotation is supported.

To further support the rotational power, the spark plugs 96 may continue over the precisely centered position of the combustion chamber to one side Mn, in the present example by 15 °, ver puts his. It should be noted that these measures can be used in any embodiment of the machine according to the invention regardless of whether a piston according to FIG. 5 or two or more pistons are used. The last-mentioned measure has very little impact on the excellent power-to-weight ratio of the rotary piston internal combustion engine according to the invention.

609820/0474

effect, because at least twice as many power pulses per revolution as "are generated in other rotary piston internal combustion engines of conventional design.

The way and way in which the fuel-air mixture in the inventive Machine initiated with two pistons is similar to the one-piston version described above; the same applies to the ignition system and the cooling devices.

609820/0 /, Ή

Claims (3)

Claims 1. Two-stroke rotary piston internal combustion engine, characterized in that that it performs at least four working strokes per revolution and piston. 2. Four-stroke rotary piston internal combustion engine, characterized in that that it performs an even number of working strokes per revolution and piston. 3. Machine according to claim 1 or 2, characterized by at least a piston reciprocable in a rotatable combustion chamber (23; 79). 4. Rotary piston internal combustion engine, characterized in that it has at least one piston (23; 79) which can be reciprocated in a rotatable combustion chamber, and that piston and combustion chamber can only be rotated opposite to the direction of rotation of the crankshaft (36; 85) of the machine. 5. Rotary piston internal combustion engine with a housing and one of its walls formed combustion chamber, characterized by at least two spacer elements (15; 8S), which together with the Chamber walls (12, 18, 21) at least one in the cylindrical Chamber (11; 89) form rotatable combustion chamber, at least one slidably arranged in the combustion chamber and the combustion chamber in piston (23; 79) dividing two parts, which has a slot (34; 83) for receiving a crankshaft (36; 85) and for rotating it Having crankshaft, the crankshaft in the housing (10) 2452 * 49 - 15 - is mounted and its axis of rotation is perpendicular to that of the combustion chamber and the piston or pistons extends, furthermore a device (42, 54, 59, 61, 66 ... 69) for supplying a fuel-air mixture into the chamber, a device (49, 51, 56, 60, 73; 96) for igniting the mixture at the right time, a device (22, 41, 53, 58, 62) for discharging the combustion products of the mixture after combustion and a device (73 ... 40, 43, 45, 46; 92 ... 94) which causes piston and Turn the combustion chamber in the opposite direction to the crankshaft. 64 Machine according to Claim 5, characterized in that the The housing (10) is closed off at one end by a cover plate (22) which forms an end wall (21). 7. Machine according to claim 5 or 6, characterized by its operation as a two-stroke machine. 8. Machine according to one of claims 5 to 7, characterized in that that the device for supplying the fuel-air mixture comprises inlet openings (42, 54, 59, 61), which with the cylindrical chamber (11; 89) are in direct communication in such a way that they are opened by moving past the piston or pistons (23; 79) and are closed, furthermore a suction manifold (68) molded into the housing (10), which at one end directly communicates with the openings, furthermore a bypass valve (69) provided at the other end of the manifold, a with the fan (67) connected to the valve and a carburetor (66) connected to the fan. 6 0 9 8? 0/0 Λ 7 i 9. Machine according to one of claims 5 to 8, characterized in that the ignition device is connected to the crankshaft (36; 85) functionally connected distributor (73) and with the cylindrical chamber (11; 89) connected spark plugs (49, 51, 56, 60; 96), which are connected to the distributor in such a way that the spark plug in question to that Time ignites at which a piston (23; 79) it is essentially in the uppermost position of its intake-compression stroke happened. 10. Machine according to one of claims 6 to 9, characterized in that that the exhaust device is formed in the cover plate Comprises exhaust gas collecting line (22) and outlet openings (41, 53, 48, 62) communicating with the Bronn chamber, which be opened and closed by the piston or pistons (23: 79). 11. Machine according to one of claims 5 to 10, characterized in that that the or each piston (23-79) at both ends has widened head portions, that on the circumference of each Head portion a continuous groove (29, 30; 90) is provided with a rectangular cross-section, in the two L-shaped spacer elements (28, 28a; 91) are fitted with a rectangular cross-section, which are provided by corrugated tongues (31) provided in the groove against the chamber walls (18, 21) are pressed outwards and seal the head portions so that each piston has two rotatable Forms combustion chamber parts and the fuel is ignited alternately on both end faces of the piston in question and that each piston has a narrow central section (33, 82) has, in which a slot (34; 83) for receiving the crank 609820/0 /, IL 2452U9 - 17 shaft (36; 85) is provided. 12. Machine according to one of claims 5 to 11, characterized in that that two segment-shaped spacer elements (15) are present, which in the cylindrical chamber (11) by a single Pistons (23) form a combustion chamber divided into two parts. 1.3. Machine according to one of Claims 5 to 12, characterized in that that the device which causes the piston (23) and combustion chamber to rotate in the opposite direction to the crankshaft (35), a gear (37) connected to the crankshaft, a pair of idler gears (38, 39) driven by this gear a countershaft (40) surrounding the crankshaft and having at one end a gearwheel driven by the intermediate gears (43) and at its other end lugs (45, 46) which are in contact with the spacer elements (15) and these drive, with all gears in the housing (10) are mounted. 14. Machine according to one of claims 10 to 13, characterized in that that the individual outlet openings (41, 53, 58, 62) are offset from one another by 90. 15. Machine according to claim 14, characterized in that the inlet openings (42, 54, 59, 61) substantially opposite the Outlet openings (41, 53, 58, 62) are arranged. 609820/0 ^ 74 2452U9 16. Machine according to one of claims 11 to 15, characterized in that that at both ends of the piston (23) baffle or deflection walls (57) are arranged, which prevent the Fuel-air mixture blown into the combustion chamber directly through it and to the outlet openings (41, 53, 58, 62) flows out. 17. Machine according to one of claims 12 to 16, characterized in that that the spacer elements (15) arcuate outer 'surfaces (16) with sealing edges along their circumference and with flat inner surfaces in contact with the rotating device (17) exhibit. 18. Machine according to claim 17, characterized in that the Spacer elements (15) have a recess in their flat surfaces (17) (20) for better engagement with the lugs (45, 46) on the countershaft (40). 19. Machine according to one of claims 5 to 11, characterized in that that several sector-shaped spacer elements (88) are provided with the side walls (18, 21) of the cylindrical Chamber (89) form two combustion chambers lying perpendicular to one another in a plane, and that in each of the two combustion chambers a piston (79) is slidably disposed, the two pistons having mutually offset central portions (82) in which a slot (83) for receiving the crankshaft (85) is provided in each case. 6 0 9 8 2 0/0 U 1 L 20. Machine according to claim 19, characterized in that the means that causes the pistons (79) and combustion chambers rotating opposite to the crankshaft (85), a gear (37) connected to the crankshaft, a pair of through this gear driven idler gears (38, 39) and a counter shaft surrounding the crankshaft (94), which on her one end of a gear (43) driven by the intermediate gears and at its other end lugs (93) which are in a pair from slots (92) provided on one of the pistons. 21. Machine according to claim 19 or 20, characterized in that the individual spark plugs (96) by 45 ° over the circumference the chamber (89) are offset from one another and that the first spark plug is 15 ° from the top of the machine is offset to the right to help rotate the machine in the correct direction. 609820/0 L e r s e i t e