DE2359682A1 - COMBUSTION ENGINE - Google Patents

Description

HEINZ LINSER -PATENTANWALT PhYSiKEPt

6072 DRE I ICHENHAI N BERLINER RING 170 CALL (061-03 ') - 8 18 13

Fu 5o6.D

Susumu Matsuo
Chosen - Cho,
Sunto - gun,
Shizuoka - ken,
Japan

Internal combustion engine

The invention relates to an internal combustion engine and in particular to one which operates according to the two-stroke process is working.

In the course of the development of the present invention, the reasons for the generation of harmful exhaust gases in conventional Internal combustion engines determined, which are presented in more detail below.

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BATH ORIGINAL

A) Four-stroke internal combustion engines for motor vehicles. (Cause 1)

As is well known, it is a four-stroke internal combustion engine designed so that the combustion ratio is best at the time the throttle valve is fully open Has value. The amount of fuel and air that is sucked into the engine is reduced when the power is reduced, for example at low speed or idling, reduced to a fraction of the normal amount so that the output of the machine is reduced. When a motor vehicle is driven with an output power of the machine, which is throttled too much, so the ratio of Fuel is extremely unfavorable to air and takes place because the fuel is atomized by injection from a pre-nozzle combustion with insufficient air (oxygen). The fuel is therefore insufficiently burned, and the gas resulting from this insufficient combustion becomes exhaust gas given outside. It should also be noted that if the fuel consumption is reduced to a minimum in the space between the piston head, and the cylinder head on every intake stroke a strong negative pressure is generated, so that a considerable amount of oil, which lubricates the cylinder wall, after is sucked into the combustion chamber below. This lubricating oil is produced by the heat generated during the work cycle decomposed and released to the outside in the form of a strong smoke.

(Cause 2)

The generation of harmful exhaust gases is of the unfavorable design attributable to the combustion chamber. Indeed, this error is found in both reciprocating and rotary engines. As is well known, the combustion chamber of an automotive engine has a relatively large surface (a thermally conductive surface) and

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BATH ORIGINAL

the combustion takes place in a confined space that prevents the flame from spreading. One assumes that a fuel-air mixture with an insufficient oxygen content is introduced into such a combustion chamber, so that combustion is just barely possible, so ■ harmful exhaust gas is produced as a natural consequence. A motor vehicle equipped with such a high-performance internal combustion engine generates during the City driving generates a large amount of exhaust gas and is therefore heavily polluted the surrounding air.

B) Two-stroke internal combustion engine for motor vehicles. (Cause 1):

With the two-stroke engine, the reciprocating movement of the piston advantageously used to remove the exhaust gas from the To pump the combustion chamber and to introduce fresh air. However, this poses a difficult problem in terms of lubrication, since the Sehmiermittelöl with the Fuel-air mixture mixed in the pumping action and in the combustion chamber is guided, regardless of whether that Lubricant oil is fed by a pump or mixed with the fuel. That way into the combustion chamber Any oil that gets into it is therefore subject to thermal decomposition subject to what black plumes and noxious fumes causes. /

(Cause 2) - "...;.

The following is the problem of incomplete combustion investigated in an engine under partial load. During slow driving or when idling, the combustion mixture is drawn in s in the crankcase is reduced to a minimum with the help of the control flap of the carburetor. Thus, only a very small volume of a combustible mixture of the air nozzle is injected into the interior of the cylinder. at the two-stroke engine, the exhaust is carried out at the moment

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guided, where the piston is near the lower dead point, and in the cylinder remains exhausted gas in an amount equal to the difference obtained by subtracting the volume of the fresh fuel-air mixture from the total volume of work. If the internal combustion engine is under partial load, become a relatively large amount of remaining spent gas plus a very small amount of fresh combustible Compressed mixture and subjected to combustion. Combustion is therefore in such poor conditions not satisfactory and the work cycles are both irregular and slow due to the constant lack of air Power. In this case, the exhaust gas contains a large amount of carbon monoxide and other harmful gases in the form a thick cloud of smoke to the outside.

(Cause 3)

When the piston reaches bottom dead center, both the intake and exhaust ports are opened and in fresh fuel mixture flows in and replaces the used one Gave.

A part of the fresh combustion mixture, however, mixes with the used gas and becomes together with it released to the outside world. An equal amount of used gas therefore remains in the cylinder. Because of this fact results Incomplete combustion, which reduces the output power, at the same time the output of a incompletely burned gas takes place.

The reasons for the generation of harmful gases listed above can be attributed to the following factors:

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On the lack of oxygen;

the unfavorable design of the combustion chamber; the. Mixing of the lubricant oil with the combustion mixture and

the outflow of the combustion mixture.

The present invention solves these identified problems.

The invention is therefore based on the object of a two-stroke internal combustion engine to propose -which doesn’t release any harmful consumed gases to the outside world. ·

Another object of the invention; is a two-stroke internal combustion engine propose in the fresh air before injecting the combustion mixture into the Cylinder is introduced so that-this is rinsed and with at the same time it prevents an insignificant amount of fuel mixture from escaping from the cylinder.

Another object on which the invention is based is to propose an internal combustion engine which does not have incomplete combustion caused by the lack of oxygen in the cylinder in the conventional gasoline engine at low speed or idling.

Yet another object of the invention is to provide a To propose internal combustion engine in which the consumed gases are burned repeatedly at low speed or idling so that no harmful used gases are released to the outside.

409883/0274

Another object on which the invention is based exists in proposing an internal combustion engine using an air-fuel pump, to prevent the ingress of lubricating oil into the cylinder, thus preventing the discharge of harmful gases completely is prevented, which on the other hand by a thermal high-temperature decomposition of the lubricant oil in the cylinder would occur.

There are further objects on which the invention is based in the following:

By using an internal combustion engine with a cylinder in the shape of an inverted '' U '' and a spherical one Combustion chamber on the cylinder head, the complete combustion of the fuel-air mixture is achieved;

by the combination consisting of a cylinder in the form of an inverted "IJi ¹ and a pair of supply pumps, one for air and one for the fuel-air mixture, a compact internal combustion engine is created;

the internal combustion engine has means which allow the fuel / air mixture to be burned from the consumed To absorb heat from gases at an increased temperature, so that the combustion mixture is preheated with the help of thermal exchange at low speed or while idling and thereby enables more economical use of the liquid fuel and increased power generation;

the proposed internal combustion engine can use liquefied propane gas and other combustion gases as fuel and only requires a conventional carburetor; and

the internal combustion engine according to the invention does not generate

A 0 98 8-3 / 02 7 4 ~ ⁷ ~

only no harmful gases consumed * but also has a / improved / efficiency. _: ·

The solution to these tasks is that at the beginning cited internal combustion engine in addition to a fuel mixture inlet slot in the engine cylinder an air inlet slot is present, with the help of which the cylinder is flushed out before the fuel or fuel mixture inflow when the relevant piston is in the area of the bottom dead center. In doing so, a certain amount of enriched fuel mixture is used in the correct one Amount introduced relative to the purge air.

As mentioned earlier, leads in the conventional internal combustion engine the combustion mixture from the used gas and thus becomes part of the combustion mixture with the used gas released to the outside, with an equal Amount of consumed gas remains in the cylinder and causes the dilution of the combustion mixture. Eventually results Giving out of harmful gases from fuel combustion at the resulting wrong ratio.

According to the present invention, the discharge of the consumed gas is through the supply of fresh air before the Introduction of the Verhrennungsgemisehes in the cylinder causes. Adding air before the mixture solves the above Problems. This pre-air causes the inside of the cylinder to be cooled and at the same time prevents this from happening immediately subsequent combustion mixture mixes with the spent gas at a high temperature. This measure is very effective in preventing both knocking and pre-ignition, thereby making the assumption of a desired one Ratio without the addition of an anti-knock agent to the Fuel is allowed.

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The feed is used at a low speed or when idling of scavenging air rather as an oxygen source than as a gas discharge. In particular, with a low Speed or idling a relatively small amount of combustion mixture supplied to the cylinder. With the conventional Internal combustion engine will consume the small amount of combustion mixture with a relatively large amount Gas mixed, resulting in misfire. When the combustion mixture is repeatedly fed to the cylinder without being burned until a sufficient amount of oxygen has accumulated in the cylinder, so occurs the combustion when it occurs is very incomplete. This results in a large amount of harmful exhaust gases.

In the internal combustion engine according to the invention is at Fresh air is supplied to each cycle, which ensures that a sufficient amount of oxygen is supplied. With a small one Speed or idling, the amount of fresh air supplied is the same as at normal speed, while, on the other hand, the amount of combustion mixture supplied is far less. Although, therefore, a relatively large one Amount of consumed gases is left behind in the cylinder, these remaining consumed gases with a relative large amount of fresh air plus a relatively small amount of combustion mixture mixed and repeated and complete burned. The used gases are therefore not released to the outside until repeated combustion below Presence of abundant fresh air has taken place, so that the emission of noxious stale gases is nearly is completely prevented. Furthermore, according to the invention, at a low speed or when idling, the fresh Air is advantageously heated to an elevated temperature by the used gases, thereby reducing the efficiency of the Internal combustion engine is improved. This effect will be explained in detail later.

409883/0274 " ⁹ "

In an internal combustion engine according to the invention a stream of fresh air is supplied to the cylinder prior to the injection of the fuel / air mixture, so that the exhausted Gases are discharged and it is prevented that not once a small amount of the combustion mixture escapes without combustion. The supply of a sufficient one becomes finer Amount of air in the cylinder at a low speed or while idling, at the same time the repeated combustion of the used gases and the preheating of the combustion mixture to an elevated temperature the consumed gases takes place.

In a further development of the invention, a pump is connected to the crankshaft of the engine and is driven synchronously by this, the fuel mixture to the fuel or Fuel mixture inlet port is pumped.

In a further embodiment of the invention, the Internal combustion engine a pair of cylinders; with associated Pistons on, with the cylinders at the top of the cylinder head have a common combustion chamber and one of the Cylinder an air inlet slot and a fuel or Has fuel mixture inlet slot, while the other Cylinder is provided with an exhaust port, and the air inflow before the fuel or fuel mixture injection takes place in one of the cylinders. The cylinder pair is. integrally connected in the form of an inverted "U" and the associated pistons are connected to a single crankshaft stroke. Advantageously, are one Air and a fuel or fuel mixture pump are present, which adjoin the cylinder pair and are designed such that they can be driven synchronously by the engine crankshaft.

409883 / 027-4

- 1ο -

The invention is based on the drawing, in which several Embodiments are shown, explained in more detail. Here show:

Figure 1 is a schematic representation of the internal combustion engine according to the invention, wherein various operations are shown;

Figure 2 is a schematic representation of the internal combustion engine according to Figure 1, with an air preheater is provided;

Figure 3 is a schematic representation of a modified Form of the invention;

Figure 4- a section from the front according to the internal combustion engine according to Figure 1;

FIG. 5 shows a section from the left side according to the illustration according to Figure 1;

FIG. 6 shows a section through the cylinders of the internal combustion engine according to Figure 1 and

FIG. 7 shows a cross section through the cylinders of the internal combustion engine according to Figure 1 at the level of the air inlet slot.

The structure of the crankshaft housing is essentially similar to that of a conventional multi-cycle internal combustion engine. Vie can be seen from the drawing, the internal combustion engine according to the invention has a two-stroke cylinder pair, which are integrally connected to one another in such a way that they act in the same way as a four-stroke engine. The upper part of the engine structure has a pair of two-stroke cylinders 1 and

409883/0274

2, which are combined in the form of an inverted ^u ü ", the lower part of the arrangement having a short-stroke air pump 15 and a short-stroke fuel-air mixture pump 16 which adjoin the cylinders. Cylinders 1 and 2" have a common spherical combustion chamber 3, which also serves as a cylinder head cover.

As can be seen from the drawings, one of the two cylinders (which is denoted by 1) · those in the form of a inverted '' TJ "are integrally connected to each other, one Air inlet slot 4 and a fuel and air mixture inlet slot 5 »while the other cylinder 2 has only one exhaust slot 6 has. Both cylinders represent the appearance of an elongated cylinder. The pistons 8 and 9 are located in cylinders 1 and 2. The air inlet slot 4 is located above the fuel and air mixture inlet slot 5. For these reasons, when the piston 8 moves downward, the air inlet slot 4 is opened first, so that Air can enter the cylinder, and then the fuel and air mixture inlet slot opened, which in the same way the penetration of the combustion mixture into the cylinder allowed.

The pistons 8 and 9 of cylinders 1 and 2 are connected to a common crankshaft pin 12 via connecting rods 1o and 11 attached. Likewise, pistons 15 and 16 are Air and combustion mixture pump via connecting rods 1? and 18 attached to a common crankshaft crank pin, such as can be seen from the drawings, synchronously movable up and down by 180 ° out of phase. At. this particular execution example is the radius of rotation of the crank pin ens 19, which drives the pumps, is half the size of the Rotation radius of the crankshaft hub pin 1 ?, which is of the Machine is driven. A check valve 21 acts as

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Air inlet valve of the air pump, while a check valve 22 works as an inlet valve for the fuel and air mixture pump 16. A control flap 2o is used for the inlet to limit the fuel and air mixture.

The crankshaft axis is used to improve the valve effect "0" offset to the right by the distance 'I "from the boundary line" C "between the two cylinders 1 and 2. This offset is not essential but an advantage.

Because of the same length of the connecting rods 1o and 11, the piston 8 is held above the piston 9 as long as the crankshaft crank pin 12 is on the right side of the semicircle, based on the boundary line "C" (see FIG. 1A) ₁ Piston 8 remains below piston 9 as long as crankshaft stroke pin 12 is on the left semicircle side (see FIG. 1B).

The following is assumed:

1.) The outlet port or slot is open to automatically discharge most of the gas used;

2.) the air inlet slot is open so that the air can remove the remaining gas that has been used;

3.) the fuel and air mixture inlet slot is open to feed the combustion mixture to the cylinder, briefly before the outlet slot is closed; and

4-.) The air inlet slot, the fuel and air mixture inlet slot and the outlet slit are closed at the same time, so that the pistons 8 and 9 the air with the combustion mixture can compress in the cylinders.

409883/0274

_v ■■:,; ■■■■■■ - 13 - .- ".:..; Γ

Despite the large size of the outlet opening, there is compression and subsequent combustion of the combustion mixture. normal. The crankshaft axis ¹ O ¹ "is offset by the distance"1'V from the limit value "C"'between the two pumps in order to adjust the relative position of the pistons 15 and 16.

From Figures 4 to 6 "it can be seen in what way the enlarged ends of the two connecting rods one Each reciprocating system is connected to a single crankshaft. The enlarged ends of the two connecting rods of the pistons are with a single one Crankshaft connected while those of the pump piston with the same crankshaft but in a different one Height are connected.

As can be seen from FIG. 1A, the pistons are shown in the vicinity of the bottom dead center immediately after the end of the combustion, ie the crankshaft angle is approximately 160 ° in the forward direction. Since the center line of the crankshaft is at the distance ''! '"From the cylinder boundary line" G ^l! is offset, the piston 8 of the cylinder 1 on the inlet side is just before bottom dead center, and the air supply from the air inlet slot 4 ceases while the piston 9 of the cylinder 2 on the exhaust side reaches bottom dead center *. In this position, the cylinder 2 is filled with the used gas at a reduced pressure, while the cylinder 1 is filled with fresh air.

In Figure 1B, the crankshaft is shown in a position in which it has already passed through bottom dead center. In in this position the outlet slot 6 is closed while the fuel and air mixture inlet slot 5 is opened, so that the fuel and air mixture, which by the pump 16

409883/0274

has been compressed, in the cylinder 1 ^{- is} admitted. Regarding the phase distribution of the various gases, the lower part of the cylinder 2 is filled with the used gas, which is discharged, the lower parts of the two cylinders 1 and 2 and the spherical chamber J5 are filled with air and the lower part of the cylinder 1 is filled with filled with the fuel and air mixture injected from the fuel and air mixture inlet port 5.

In Figure 1C, the beginning of the compression stroke is shown, during this time the three different slots are closed, the cylinder 1 is with fuel mixture and the Cylinder 2 filled with fresh air. Further rotation of the crankshaft causes pistons 8 and 9 to occur simultaneously compress the air and fuel mixture. The air and the fuel mixture therefore meet in the spherical chamber 3 together and create a vortex along the inner surface of the spherical chamber. When the crankshaft is in the Is near top dead center, the secondary and the final mixing process is ended and the mixture is then ignited. The spark plug is located in the upper center of the spherical combustion chamber, so that the Flame spreads almost evenly on both sides and the combustion process is almost ideal.

Figures 1A, 1B and 1C show different states at normal or high speed, while, in contrast, FIG. 1D shows a state that corresponds to that of FIG 1C corresponds to a speed under partial load of the engine or with reduced power. There is just as much air as there is at high speed or normal operating conditions delivered, but less fuel and air mixture. Due to this fact, a Significant amount of gas consumed is left behind as the gas consumed is due to a lesser amount of fuel mixture is insufficiently rinsed. The upper parts of the

409883/0274

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"" '' /-.-■ - 15 - V ■. ■ - ■ ν-.

Cylinders 1 and 2 and the spherical combustion chamber 3 are with fresh air and the lower part of the cylinder 1 filled with a small amount of fuel and air mixture. Therefore, in the subsequent compression stroke, these different gases are completely mixed and explode, when they are ignited. There is no risk of incomplete combustion, as is the case with conventional internal combustion engines because of insufficient compression or lack of oxygen is the case. The reason why Even a small amount of fuel mixture can burn completely, comes from the distribution of the various "gases" shown in Figure 1D.

In the internal combustion engine according to the invention is provided with an air pump 15, it is possible to overfill the engine with air, so that the entire used Gas is discharged even during the idle run. In the thermal machine, however, it is more advantageous from that to make use of hot spent gas, provided, of course, that the amount of oxygen is sufficient to completely burn fresh fuel and air mixture. .

However, it is even more important that the combustible Material in the gas that has once undergone combustion in the presence of a sufficient amount of oxygen is completely burned.

From Figure 2, which relates to an engine state at partial load and low speed or idling similar to Figure 1D relates is shown; like fresh air to avoid the cooling of the cylinder by the air flow, can be preheated. A preheating of the fresh air has been done so far

4098 83/027 4

considered impossible. That coming from the outlet opening 6 Consumed gas is passed through a heat exchanger 23 with the aid of a valve flap 24 actuated at suitable times. The cold flowing through the heat exchanger 23 Air absorbs heat from the hot exhaust gas via the heat exchange and is then sucked in and compressed by the air pump 15 and finally the heated fresh air gets into the cylinder 1. The "in this way at an elevated temperature preheated air advantageously reduces the power required for compression and continuously maintains the combustion chamber at an elevated temperature. the The introduction of warm air also reduces fuel consumption in an advantageous manner and also allows the engine to run smoothly at the same time, even at a partial load.

The preheating of the supplied air was considered impossible in a staggered Xwei-cylinder machine. Lie internal combustion engine according to the present invention, v / eis a special air pump, which is designed to be heat-resistant, so that air at an elevated temperature can be used.

A conventional internal combustion engine is shown in FIG through a special opening 33 above the fuel and air mixture inlet slot 32 of the cylinder 31, according to the invention, is modified. This inlet slot 33 is used for air purging.

The piston 34 and the crankshaft pin 35 are in the shown in the lower position. At 36 is an outlet slot designated. A supply channel 37 for the fuel and air mixture extends from a fuel and air mixture pump 39 to inlet slot 32. Runs in a similar manner an air duct from an air pump 40 to the inlet port 33. These pumps are synchronized by a crankshaft 41

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driven with the cylinder piston 34 in the drawing. offset by 18o °. The crankshafts 41 'below the pumps 39 and 4o represent the engine crankshaft, although they only separated in the drawing for the sake of demonstration are shown. The crankshaft journals 35 'are of the designated by 35 and by the piston 34 and the connecting rod 42 different driven, although also a single one Crankshaft journal 35 'can be used for the two pumps can. ■ -

It is assumed that the piston 34 is moved downward when the fuel-air mixture is ignited and that the upper part of the piston "bypasses the outlet port 36 and releases it so that the used gas can escape from the opening 36. then, the inlet slit 33 is opened so that the air 4o flows into the cylinder 31 under the pressure of the pump After the gas consumed by "■ -., the air flow is completely discharged, the inlet slot 32 is opened for the fuel and air mixture so that the fuel and air mixture flows into the cylinder 31 under the pressure of the pump 39. The air is then forced into sight of the outlet slot 36. As a result, the left half of the cylinder is filled with air, while the right half is filled with a combustible mixture when the piston is in the position shown in FIG. The piston 34 then moves upwards and closes all slots 32, 33 and 36. The air and the fuel and air mixture are evenly mixed in the course of the supply and are compressed in the combustion chamber. If air and combustion mixture are supplied in the same amount, and if a terburn mixture of twice the concentration is used, the result is a gas with a correct mixing ratio. The crankcase itself can be used as a fuel and air mixture pump, as in a conventional engine. However, it is advantageous

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4098 83/0274

liable to provide a special pump and this only for the fuel and air mixture, as described in the Embodiment to use, since on the other hand the lubricant oil, as before in the description of the disadvantages of conventional machines, finds its way into the cylinder. The air pump 4o is not necessary if an appropriate source of compressed air is available. The role of the air pump can be from any one to another Purposes used pump can be adopted. A fuel and air mixture pump is not required if an air pump is used is used with such a large capacity that the first half volume of air is used to the exhaust gas discharge and the second and remaining half volume of air is flushed out and mixed with fuel mist at the same time is to create a rich fuel-air mixture directly in the cylinder to create. There are thus solved the problems that occur in a two-stroke internal combustion engine, such as the incomplete removal of the used gases and an escape of the fuel and air mixture and at the same time also the main problems of the internal combustion engine, such as the incomplete combustion of the fuel-power mixture because of the lack of oxygen in the cylinder, at a low speed or when idling. Any incomplete discharge of the spent gas and the escape of the fuel-air mixture have been considered to be the problems encountered in particularly occur in a two-stroke internal combustion engine. The incomplete combustion of the fuel-air mixture because of the lack of oxygen in the cylinder at low speed or when idling, is used in an internal combustion engine viewed as a major problem. However, according to the invention, these problems are completely solved and simultaneously the reburning of the used gas is realized by removing the air before the fuel-air mixture is supplied flushed into the cylinder. For these reasons, there are almost no harmful consumed Gases.

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The penetration of lubricant oil into the cylinder and thus the generation of harmful gases through thermal decomposition of the lubricant oil _r can be avoided by feeding the fuel-air mixture from the carburetor to a pump that is only available for the combustion mixture and by transferring the combustion mixture from this pump to the Inlet slot "of the cylinder is pumped.

The combination of a cylinder in the form of an inverted "U ^K " with a spherical combustion chamber ensures complete combustion of the fuel-air mixture and the provision of an air pump and a pump for the combustion mixture makes the internal combustion engine fully suitable for practical use. .. "" ■ ". ■ - ■ -

As is already known, the cooling effect caused by the air purge is caused, an increase in performance » which is available at an increased speed. However, preheating the purge air reduces fuel consumption at low speed or idling and the internal combustion engine according to the present invention, realized for first time the idea of preheating the purge air with hot consumed gases. The use of a gas and air mixture from a liquefied petroleum in a two-stroke engine causes pre-ignition and other dangers, so that the use of such a fuel mixture so far was considered impossible. However, if the internal combustion engine according to the invention is combined with a carburetor, which is used in KMt vehicles that are used be operated with liquefied petroleum gas, and if a fuel mixture with a high ratio of fuel gas to air is used ^ so the internal combustion engine runs without pre-ignition and without other dangerous difficulties.

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Claims (1)

Claims Internal combustion engine, especially two-stroke engines, characterized in that in addition to a fuel or fuel mixture inlet slot (5) there is an air inlet slot (4) in the engine cylinder (1,?), With the aid of which the cylinder (1, 2) is flushed out before the fuel or fuel mixture inflow when the relevant piston is in The area of the bottom dead center. ?. Internal combustion engine according to claim 1, characterized in that a pump (15 or 16) is connected to the crankshaft of the engine and is driven synchronously by this, the fuel mixture being pumped to the fuel or fuel mixture inlet slot (5). . '. - Internal combustion engine, characterized by a pair of cylinders (1,?) With associated Pistons (8, 9), the cylinders having a common combustion chamber (3) on the upper cylinder head part and one of the cylinders (Ί) an air inlet slot (4) and a fuel or fuel mixture inlet slot (5) has, while the other cylinder (?) is provided with an exhaust port (6), and the air inflow in front the fuel or fuel mixture injection in one of the cylinders takes place. -21- 409883/0274 . Internal combustion engine according to claim 3 »because you rch geke η η ζ e ic h η et that the cylinder pair (1, 2) in the form of an inverted" U ' ^{: is} integrally connected, and that the associated pistons (8 ^ 9) with a single crankshaft pin (Ί2) are connected. Internal combustion engine according to claim 3 or 4, d a d u r c h g e k e η η ζ ei c h η et that an air and a fuel or fuel mixture pump (4 and 5) are present that border on the cylinder pair (8, 9) and are designed such that they can be driven synchronously by the engine crankshaft. 6. Internal combustion engine according to claim Λ or one of the preceding, there. through - g. e ken η ze ic h η et that there is a heat exchanger (23) for preheating the scavenging air through the used gases escaping from the exhaust gas slot (6). 4 09883/02 74 Blank page