EP2165058A2

EP2165058A2 - Internal combustion engine

Info

Publication number: EP2165058A2
Application number: EP08734348A
Authority: EP
Inventors: Peter-Bernhard Kathmann
Original assignee: SENECA SA
Current assignee: VOIT, MARTIN
Priority date: 2007-02-22
Filing date: 2008-02-22
Publication date: 2010-03-24
Anticipated expiration: 2028-02-22
Also published as: EP2165058B1; WO2008101495A3; WO2008101495A2; EP2165058B8; EP1961943A1; DE112008001142A5

Abstract

The invention relates to an internal combustion engine (M) comprising a first cylinder to be operated when fuel is supplied, a second cylinder to be operated without fuel being separately supplied thereto, and an overflow connection (20; 21) that is formed between the cylinders and is fitted with a blocking member (22, 23) which can be maintained in an open position during the power stroke of the first cylinder. The pistons (10-12) in the cylinders move substantially in a synchronous fashion in relation to the top and bottom dead center, the dead volume (17) of the second cylinder is smaller than the dead volume (15, 16) of the first cylinder, and the second cylinder encompasses a discharge valve (27) that is to open during the compression phase of the first cylinder. According to the invention, the discharge valve (27) of the second cylinder can be closed by the piston (12) thereof before the top dead center is reached such that a compressive force which is applied when the blocking member (22, 23) is opened can be generated in the second cylinder.

Description

Description:

"Brennkrαftmotor"

The invention relates to a Brennkrαftmotor with a first for operation with fuel supply and a second provided for operation without own fuel supply cylinder and an overflow connection formed between the cylinders with a shut-off that can be held during the working cycle of the first cylinder in an open position, wherein the Moving pistons in the cylinders substantially synchronously with respect to the top and bottom dead center, the dead volume of the second cylinder is smaller than that of the first, and the second cylinder comprises an outlet valve provided for opening during the compression phase of the first cylinder.

An internal combustion engine of this type is shown in US 4503816. The second cylinder, into which combustion gas flows from the first cylinder during the working stroke of the first cylinder, increases the expansion volume, so that the energy contained in the combustion gas can be converted into mechanical work more completely than during expansion of the combustion gas only within the first cylinder. The exhaust valve of the second cylinder remains open with each piston stroke until the piston of this cylinder reaches its top dead center. The remaining in this position dead volume is extremely low. When opening the overflow connection, the dead volume is depressurized or there is only air pressure.

The invention has for its object to provide a new engine of the type mentioned above with respect to this prior art further improved fuel efficiency. The object of this invention solving internal combustion engine according to the invention is characterized in that the exhaust valve of the second cylinder is closed before reaching the top dead center of the piston and can be generated in the second cylinder, a voltage applied to the opening of the shut-off compression.

The inventive generation of compression pressure in the second cylinder too early, the inflammation and combustion process disturbing outflow of fuel-containing gas from the first into the second cylinder can be avoided immediately after opening the overflow. Overflowing occurs only after extensive ignition of the gas in the first cylinder. Thus, combustion proceeds in a controlled manner with highly efficient use of the fuel.

Preferably, the locking member releases the overflow connection when the compression pressures in the two cylinders are exactly equal.

In a particularly preferred embodiment of the invention, the second cylinder also has an inlet valve, through which fresh air can be pressed into the second cylinder during the compression phase of the first cylinder when the outlet valve of the second cylinder is open. Advantageously, this fresh air flushes combustion gases of the preceding cycle from the second cylinder and then ensures an afterburning of the gas flowed over into the second cylinder and thus for an even more extensive utilization of the fuel.

For the first cylinder both four-stroke and two-stroke operation are considered.

Preferably, a third, the first cylinder corresponding cylinder is provided which operates offset from the first cylinder by 360 °. The first and third cylinders may then be operated in a four-stroke mode, with the second cylinder doing mechanical work every second stroke for each downward movement of the piston.

Suitably, the three cylinders are arranged in a cylinder bank, which forms a basic module, which is connected to at least one other such

Basic module in boxer, row, V, W or star arrangement can be combined.

The reciprocating pistons of the basic module work expediently parallel to one another, Give it with identical strokes. Thanks to a much smaller dead volume in the middle cylinder, the piston in the middle cylinder needs much less energy to finally compress to the same pressure as any cylinder next to it during the combined expulsion and compression stroke. As soon as pressure equality is achieved before ignition, the overflow connection is opened, whereby thanks to the pressure equilibrium initially no noticeable overflow takes place. After ignition in the outer cylinder, the combustion pressure, which acts on the reciprocating piston in the outer cylinder directly and via the overflow now also the reciprocating piston in the middle cylinder, so that both reciprocating perform a power stroke. Since then the additional volume in the middle cylinder is available for the expansion of the working pressure, the combustion pressure can be almost completely expand, ideally to the atmospheric pressure, thanks to the expansion, the temperature is significantly reduced when the two reciprocating reach their bottom dead centers , In the other outer cylinder, an intake stroke has been performed at the same time. After the recent reversal of motion of all reciprocating piston cooperates with the middle cylinder of the other outer cylinder in the manner described above.

Suitably, the stroke of the middle piston is different from the strokes of the outer piston. Thus, for example, form a large expansion space without enlarged central piston, which keeps the axial dimensions low.

Suitably, the connecting rod angle of the middle piston is different from those of the outer piston. Then, the middle reciprocating piston reaches its dead center forward or backward, e.g. to account for a delay in ignition.

In an expedient embodiment, the two outer cylinders have inlet and outlet valves, while the middle cylinder has at least one outlet valve. This exhaust valve is used to exhaust expanded and relatively cool exhaust gas from the middle cylinder. Since the middle cylinder operates in two-stroke mode, the exhaust valve is opened only over part of the Ausschiebe- and compression stroke to build up in the smaller dead space of the middle cylinder up to a certain stroke position the same pressure in the outer, just the compression stroke exporting cylinder until the overflow connection is opened.

In an expedient embodiment, the shut-off of the overflow is a slider or a piston valve. Both the slider and the piston Valve avoid in the shut-off an undesirable Totrαum.

According to another important aspect, the middle cylinder has a larger cylinder diameter than the two outer cylinders. This increases the usable space for .Expansion space and also the loading surface of the reciprocating piston during the power stroke.

Suitably, the working cycles of the two outer cylinders are offset from each other by 360 degrees of the crankshaft rotation angle. In this way, the middle cylinder ideally works alternately with each outer cylinder at its stroke.

Another important aspect is that the exhaust valve of the middle cylinder during the Ausschiebe- and compression stroke of the reciprocating piston is aufsteuerbar only between the bottom dead center and a predetermined stroke position below the top dead center. As long as the exhaust valve is open, expanded cool exhaust gas is expelled. The closing time of the exhaust valve is chosen so that in the middle cylinder after closing the exhaust valve shortly before reaching the top dead center because of the smaller dead space, the same pressure prevails as in the outer, just the compression stroke exporting cylinder.

In order to improve the degree of filling in each cylinder, it is expedient if the internal combustion engine has a charging device.

It is particularly useful thanks to the parallel movement of the reciprocating piston of the basic module whose crankcase is used as a charge pump. The loading device may, preferably, be used primarily for loading the middle cylinder, whereby then a loading ratio of about 1: 3 can be achieved. For this purpose, it is advantageous to provide in the middle cylinder at least one positively controlled inlet valve via which the cylinder can be connected to a fuel-free charge air supply.

Here, the inlet valve serves as a purge valve during the Ausschiebe- and compression stroke in the middle cylinder, and that at least until the closing of the exhaust valve. It is supported in this way by the supply of fresh air, the pushing out of the exhaust gas, and for the subsequent power stroke in the middle cylinder

Fresh air kept ready, which is useful for a proper post-combustion of fuel from the outer cylinder. This combustion is relatively lean and high temperature, which increases the power output. This residual fuel from the outer cylinder could hardly be completely burned in the outer cylinder itself. Another advantage of the charge air supply at least to the middle cylinder is a desirable temperature reduction, optionally when using a charge air cooler.

In an expedient embodiment, the basic module as gasoline or gas engine ignition devices only for the two outer cylinder, and of course only fuel supply devices for these two outer cylinder.

In another expedient embodiment, the base module as a diesel engine on Glühvorrichtungen and Brennstoffzuführvorrichtungen only for the two outer cylinder. This reduced equipment reduces manufacturing costs and weight in both cases.

In an advantageous embodiment, the reciprocating piston of the middle cylinder at the same cylinder heights on a dead space in the middle cylinder reducing, raised piston crown.

Since the middle piston exerts relatively high force on the crankshaft in its more frequent work cycles, it is expedient to store the crankshaft between the crank pin for the three reciprocating piston and to strengthen the connecting rod of the middle piston.

Also useful are the valves or sliders camshaft actuated to achieve precise timing dependent on the crankshaft rotation.

Embodiments of the subject invention will be explained with reference to the drawing. Show it:

1 shows a longitudinal section through a basic module of the internal combustion engine, Figure 2 shows an enlarged detail variant of the internal combustion engine in the cylinder head area, Figure 3 shows another embodiment of the internal combustion engine consisting of two basic modules in the boxer arrangement, Figure 4 is an existing two basic modules engine,

5 shows a charge air lines facing outside view of the internal combustion engine of

4, and FIG. 6 different cylinders of the internal combustion engine of Figure 4 and 5. A shown in Fig. 1 Brennkrαftmotor M is either a gasoline or Gαs- (Wαsserstoff) or a diesel engine and has as basic module A three cylinders in a cylinder bank 2 of a motor housing 1 with a crank chamber 3. In each cylinder, a reciprocating piston 10, 11, 12 is contained, wherein, preferably, the cylinder and piston diameter in the middle cylinder is larger than in the two outer cylinder. The reciprocating pistons 10, 11, 12 are connected via connecting rods 9 with crankpins 5a, 5b, 5c of a crankshaft 4. The connecting rod 9 of the middle reciprocating piston 12 could be reinforced or stronger than the others. The crank pin 5a, 5b, 5c lie in a common, parallel to the axis of the crankshaft 4 axis 6, so that the reciprocating piston 10, 1 1, 12, move parallel to each other.

The two outer cylinders operate in four-stroke mode, while the middle cylinder operates in two-stroke mode. The crankshaft 4 is mounted at its ends in bearings 7 and also between the crank pin 5a, 5b, 5c, in bearings 8. In a cylinder head 13, intake and exhaust valves 18 are provided for the two outer cylinders which are positively controlled (eg by at least one camshaft, not shown). The two outer cylinders also each have at least one ignition device or annealing device 19 and also each a fuel supply device (not shown), which operates for example with fuel injection. Various popular injection methods can be used here. A fuel supply via carburetor is possible. The middle cylinder has at least one outlet valve 27, which is positively controlled. In the illustrated embodiment of the basic module A, at least one positively controlled inlet valve 28 is further provided in the middle cylinder. This inlet valve is not absolutely necessary, but it is expedient if the internal combustion engine M is operated, for example, with a charging device, as described below, in particular with reference to FIGS. 4 to 6.

Since the basic module is operated with a reciprocating piston operating in parallel, considerable pressure pulses are produced in the crank chamber 3, so that the crank chamber 3 can be usefully used as a charge pump of the charging device in order to charge at least the middle cylinder, namely via the inlet valve 28 Outlet means 25, 26 may be provided for the crank chamber 3, wherein this outlet device is then connected at least to the inlet valve 28.

The dead spaces of the two outer cylinders are indicated by 15 and 16. The dead space 17 of the middle cylinder is considerably smaller than the dead spaces 15, 16. This is achieved, for example, by the fact that the piston 12 in the middle cylinder has a raised piston crown 14 and / or due to the different Hubs of the lifting cylinder 12 or with a different connecting rod angle of the connecting rod 9 of the middle piston 12 relative to the other connecting rods 9. A significantly larger cylinder or piston diameter of the middle cylinder leads to a better power yield and energy conservation.

Between the dead space 15 or 16 of each outer cylinder and the dead space 17 of the middle cylinder overflow 20, 21 are provided, which are each opened and closed by a positively controlled shut-off G. In the basic module A shown in FIG. 1, the shut-off members G are slides 22, 23, which are arranged displaceably in the cylinder head 13 approximately parallel to the stroke direction of the reciprocating pistons. Between the crank pin 5a, 5b, 5c balancing weights 24 may be arranged on the crankshaft 4.

Function: The lifting piston 10 shown on the left in FIG. 1 executes four cycles via a crankshaft rotation angle of 720 degrees. The first cycle is the intake stroke with movement from top dead center to bottom dead center with the intake valve open and the exhaust valve closed. The second cycle is a compression stroke in which the reciprocating piston 10 moves from bottom dead center to top dead center, with intake and exhaust valves closed. At the end of the compression stroke, the ignition takes place. The third cycle is a power stroke in which the reciprocating piston 10 moves from top dead center to bottom dead center with the inlet and exhaust valves closed. The fourth cycle is a Ausschiebetakt in which the reciprocating piston 10 moves from bottom dead center to top dead center, and in which the exhaust valve is opened and the inlet valve is closed.

The right in Fig. 1 lifting piston 11 performs its four bars with a 360 degree offset from the clocks of the left cylinder.

While the left-hand piston 10 in FIG. 1 carries out its intake stroke, the overflow connection 20 is closed, whereas the overflow connection 21 is opened. The middle piston 12 cooperates with the right piston 11, to the effect that the combustion pressure from the right in Fig. 1 cylinder on the overflow 21 and the middle piston 12 acts, the power to the crankshaft 4 outputs. In the middle cylinder, the exhaust valve is closed during this power stroke, and if present, the inlet valve 27. At the compression stroke of the left piston 10 from the bottom dead center, the exhaust valve 27 of the middle cylinder is opened, as well as the exhaust valve of the in Fig. 1 right cylinder. The exhaust gases are ejected. Depending on the size of the dead space 17 and its ratio to the dead space 15, the exhaust valve 27 of the middle cylinder is closed from about 45 degrees crankshaft rotation angle before top dead center. The middle piston 12 then begins to compress, since both shut-off members G are in the closed position. As soon as the pressures in the dead spaces 15, 17 are the same, the slide 22 is opened, approximately with the ignition in the left outer cylinder, or forward or retarding to the ignition. The combustion pressure in the left-hand cylinder in FIG. 1 now also acts on the middle lifting piston 12, which transmits power to the crankshaft 4 and, above all, provides additional expansion volume in order to expand the combustion pressure totally or almost completely until it is close to atmospheric pressure.

If the internal combustion engine M has a supercharger, and the inlet valve 27 is provided in the middle cylinder, the inlet valve is opened during the compression and exhaust stroke of the middle piston 12, even though the exhaust valve 27 is open. For example, the intake valve is opened about 45 degrees crankshaft rotation angle after the bottom dead center and closed in approximately concurrent with the exhaust valve 27, d. h, at about 45 degrees before top dead center. As a result, fuel-free fresh air is introduced into the middle cylinder to expel (purge) the exhaust gas and introduce fresh air. This fresh air can be used to post-combust fuel from the left-hand cylinder in FIG. 1, this post-combustion being lean and high-temperature, i. a favorable power yield allows.

When the bottom dead center is reached, both slides 22, 23 are closed. The left in Fig. 1 lifting piston 10 then performs its Ausschiebetakt, while the right in Fig. 1 lifting piston 11 performs its compression stroke until the right in Fig. 1 slide 23 is opened again.

Thus, each outer reciprocating piston 10, 11 performs a power stroke at every third clock, while the middle reciprocating piston 12 performs a power stroke every second clock.

The Ausführungsfprm in Figure 2 differs from that of Fig. 1 by another embodiment of the shut-off members G. Instead of the slide 22, 23 piston valves 31, 32 are used, which are guided in the cylinder head 13 slidably. Each piston valve has a valve plate 31 and an actuating piston 32. For the valve plate 31, two spaced valve seats 30 and 29 or 34 and 33 are provided in the overflow connection 20, 21. The construction of the piston valve avoids in the closed position an inappropriate dead space. Furthermore, the piston valve located in the closed position (on the right in FIG. 2) is held in close contact with its valve seat 33 by the combustion pressure. This avoids leakage.

3 shows an internal combustion engine M, which is composed of two basic modules A together, which form a 180 ° -Boxeranordnung. In addition to the crankpins 5a, 5b, 5c, the crankshaft 4 'in the crankcase 3a has crankshaft journals 5d, 5e and 5f offset by 180 degrees about the crankshaft axis for the three other reciprocating pistons of the lower basic module A. The firing order can be crossed or directly opposite one another. Also in this internal combustion engine M, the crank chamber in the crankcase 3 can be used as a charging pump of a charging device, or supplement a charging device, if the working in four-stroke cycle cylinder are operated with charge.

Since in the ideal case a total expansion of the combustion pressure with direct conversion into mechanical energy in the engine itself can be achieved, the exhaust gas pressure and the exhaust gas temperature are low. The internal combustion engine can be operated with low thermal load, i. It hardly needs cooling power in operation, rather even good thermal insulation. There is hardly any residual pressure wasted, which relieves the exhaust system. Especially with the charge and the inlet valve 27, the energy contained in the fuel is better utilized. If necessary, a small catalyst is sufficient to meet the exhaust gas regulations, or a catalyst is completely unnecessary (or a soot filter). Since the basic module with three reciprocating pistons operates in series order like a four-cylinder, and also delivers corresponding power, compact dimensions can be achieved at least in the direction of the crankshaft axis, and the weight of the internal combustion engine can be reduced. With test engines built and operated, the efficiency was about 50% or more compared to conventional power engines, with reduced weight and smaller dimensions, and with lower specific fuel consumption.

Reference is now made to Figures 4 to 6, in which a two basic modules Al and A2 in series existing engine is shown schematically. Each module has three cylinders 50, 51 and 52 or 50 ', 51' and 52 ', whose pistons are each connected via a connecting rod 53 with a continuous crankshaft 54 common to both modules A1 and A2.

Between crankcases 55 and 55 'of the modules Al and A2 is a partition wall 56th

The crankshaft 54 is connected via a drive element 57 with a camshaft 58 common to both modules A1 and A2. The camshaft 58 controls an intake valve 59 and an exhaust valve 60 per cylinder.

Between the cylinder 51 bzw.51 'of each module and the two outer cylinders 50, 52 and 50', 52 ', an overflow channel 61 is provided in each case, which can be shut off by a controlled by the cam shaft 58 slide 62. The middle piston 51 or 51 'in each case has an elevation 63, which significantly reduces the dead volume of the relevant cylinder in comparison to the outer cylinders.

On the outer cylinders of both modules Al and A2 devices 64 are provided for ignition.

As can also be seen in FIG. 4, the engine housing is divided into three parts, into a cylinder head part 65, a main block 66 and a trough part 67 closing off the main block.

As is apparent from Fig.5, on the outside of the motor housing charge air lines 68 and 69 or 68 'and 69' are provided, which are connected to an opening 78 or 78 'in the wall of the main block 66 and, accordingly, in connection with the crankcase 55 and 55 'and leading to inlet openings 80, 81 and 80', 81 'of the cylinders 50 and 52 and 50' and 52 ', respectively. In front of the opening 78 or 78 'on the outside of the main block 66, a block 79 or 79' is arranged, which establishes a connection between the opening 78 bzw.78 'and the charge air lines 68, 69 and 68', 69 '. Furthermore, the block has a passage to the opening 78 or 78 ', in which a check valve 70 or 70' is provided. Finally, opens into the block one with the opening 78 and 78 'connected to a conduit 73 which establishes a connection between the crankcases 55 and 55' and the passage cross-section can be adjusted by means of a rotary valve 74. The air supply lines 68 and 69 or 68 'and 69' communicate with the inlet valves 59 of the cylinders 50, 52 and 50 ', 52', respectively. Of the Lαdeluftleitungen 68 and 69 or 68 'and 69' branches off in each case a continuous connecting line 75 or 75 ', in the check valves 76 and 77 or 76' and 77 'are provided and in connection with an inlet port 82 and 82 'of the cylinder 51 bzw.51' is.

The reference numerals 83 and 83 'and 84 in Fig. 6 indicate exhaust ports of the cylinders 50, 50', 51.

In the following the operation of the internal combustion engine described with reference to FIGS. 4 to 6 will be explained.

As in the previous embodiments, the outer cylinders 50, 52 and 50 ', 52' of the modules Al and A2 operate under fuel supply in four-stroke operation, wherein these cylinders are mutually offset by 360 ° within the modules. The modules Al and A2 in total work offset from each other by 180 °, i. when the pistons of cylinders 50, 51 and 52 are at top dead center, cylinders 50 ', 51' and 52 'are at bottom dead center and vice versa. In the middle cylinders 51, 51 'flows in the downward movement of the piston through the relevant overflow 61 ignited gas from one of the adjacent cylinder, in the next cycle during the upward movement of the piston through the relevant outlet valve 60 and the outlet port 84 therethrough (Fig. 6b ) is ejected from the middle cylinder.

In the embodiment according to FIGS. 4 to 6, the outer cylinders 50, 52 and 50 ', 52' are charged in their intake stroke by compressed air from the crankcase 55 or 55 '. The compressed air is caused by the fact that in this phase all three pistons move in the direction of the crankcase and compress the air in the crankcase.

Such a charging process will be explained below by way of example with reference to the charging of the cylinder 50.

During the intake phase of the cylinder 50, in which the piston moves toward the crankcase 55, compressed air passes through the exhaust port 78, the charge air line 68 and the intake port 80 into the cylinder 50. The exhaust valve 60 of the cylinder 50 is closed. The pistons of Cylinders 51 and 52 are in this Ansαugphαse of the cylinder 50 in a working cycle. With the inversion of the piston movement upwards in the cylinder 50, the compression phase begins. The corresponding outlet valve 60 of the adjacent central cylinder 51 is opened, so that gas is expelled from the cylinder 51 through the outlet opening 84. Likewise, the exhaust valve 60 of the cylinder 52 is opened. The intake valves 59 of the cylinders 51 and 52 and both valves of the cylinder 50 are closed.

Approximately at an angle of 45 ° after the bottom dead center of the piston of the middle cylinder 51, the inlet valve 59 of this cylinder is opened. Compressed air from the crankcase 55, which is trapped in the connecting line 75 through the check valves 76, 77 since the suction phase passes through the inlet port 82 and the inlet valve 59 into the cylinder 51 and flushes exhaust gas contained therein of the preceding power stroke from the cylinder. About 45 ° before top dead center, both the inlet valve 59 and the outlet valve 60 of the middle cylinder 51 are closed. On the remaining distance of the piston of the middle cylinder 51 now takes place as in the cylinder 50, a compression.

At the top dead center of the piston of the cylinder 51, approximately equal compression pressures are achieved both in the cylinder 50 and in the cylinder 51, and the slider 62 in question is opened by releasing the overflow channel 61. Due to the equal pressure in both cylinders, the flow through the overflow channel 61 does not yet occur at this moment and the ignition of the fuel / air mixture in the cylinder 50 is not disturbed. Only in the further course of pressure in the cylinder 50 also comes to act on the piston of the cylinder 51 by overflowing hot combustion gases.

By the flushing of the cylinder 51 is located in the cylinder 51 compressed fresh air, which provides for afterburning the overflowed into the cylinder 51 gas and thus for a further increase in efficiency.

As the air in the crankcase 55 is compressed, vacuum is created in the crankcase 55 'by the simultaneous stroke of the three pistons, and air is drawn into the crankcase 55' through the block 79 '. Via the connecting line 73 and by opening the rotary valve 74 therein, the charge air pressure generated by the respective other module Al or A2 can be regulated. It is understood that a dry sump lubrication is used for the engine described in FIGS. 4 to 6, which allows a charge of the cylinder with oil-free air.

Claims

claims:

An internal combustion engine having a first (50, 52) for operation with fuel supply and a second (51) provided for operation without own fuel supply cylinder and one between the cylinders (50, 52, 51)

Overflow connection (20, 21, 61) with a shut-off member (22, 23, 62) that can be held in an open position during the working stroke of the first cylinder (50, 52), wherein the pistons in the cylinders (50-52) move substantially synchronously with respect to the top and bottom dead center, the dead volume (17) of the second cylinder (51) is smaller than that (15, 16) of the first cylinder (50, 52) and the second cylinder (51) an exhaust valve (27; 60) provided for opening during the compression phase of the first cylinder (50,52), characterized in that the exhaust valve (27; 60) of the second cylinder (51) is closable by its piston before reaching top dead center , And so in the second cylinder (51) can be generated when opening the shut-off member (22, 23, 62) applied compression pressure.

2. An internal combustion engine according to claim 1, characterized in that the shut-off member (22, 23; 62) is provided for opening with equality of the compression pressures in the two cylinders (50, 52, 51).

3. Internal combustion engine according to claim 1 or 2, characterized in that the second cylinder (51) has an inlet valve (28; 59) through which during the compression phase of the first cylinder (50, 52) with open outlet valve (27; 60) fresh air in the second cylinder (51) is pressed.

4. Internal combustion engine according to one of claims 1 to 3, characterized in that a third, the first cylinder (50) corresponding cylinder (52) is provided, which operates offset from the first cylinder (50) by 360 °.

5. Internal combustion engine according to claim 4, characterized in that the three cylinders (50-52) are arranged in a cylinder bank (2) which forms a basic module which can be combined with at least one further such basic module in boxer, row, V, W or star arrangement.

6. Internal combustion engine according to claim 4 or 5, characterized in that the pistons (10, 11, 12) of the three cylinders with crankshaft journals (5a, 5b, 5c) are connected to a crankshaft, in one, at least substantially common to the crankshaft axis parallel axis (6) lie.

7. Internal combustion engine according to one of claims 4 to 6, characterized in that the three reciprocating pistons (10, 11, 12) have identical strokes or that the stroke of the middle piston (12) is different from the identical strokes of the two outer piston (10 , 11).

8. Internal combustion engine according to one of claims 4 to 7, characterized in that the connecting rod angle of the connecting rod (9) of the middle piston (12) is slightly different from the connecting rods of the connecting rod of the two outer piston (11, 13).

9. Internal combustion engine according to one of claims 4 to 8, characterized in that the shut-off member (G) of the overflow connection (20, 21) is a slide (22; 62) or a piston valve (31, 32).

10. Internal combustion engine according to one of claims 4 to 9, characterized in that the central cylinder has a larger cylinder diameter than the two outer cylinders.

11. Internal combustion engine according to one of claims 4 to 10, characterized in that the outlet valve (27) of the middle cylinder during Ausschiebe- and

Compression stroke of its reciprocating piston (12) only between the bottom dead center and a predetermined stroke position below top dead center, preferred way at about 45 degrees crankshaft angle before top dead center, is aufsteuerbar.

12. Internal combustion engine according to one of claims 4 to 11, characterized in that a charging device is provided.

13. An internal combustion engine according to claim 12, characterized in that the charging device, the crankcase (3, 3a) summarizes as a charge pump.

14. Internal combustion engine according to one of claims 3 to 13, characterized in that the inlet valve (28) of the middle cylinder as flushing valve during the Ausschiebe- and compression stroke in the middle cylinder at least until closing of the exhaust valve (27) aufsteuerbar, preferably from about 45 Degree of crankshaft rotation angle after bottom dead center.

15. Internal combustion engine according to one of claims 5 to 14, characterized in that the basic module (A; AI, A2) as gasoline or gas engine ignition devices (19, 64) only for the two outer cylinders (50,52).

16. Internal combustion engine according to one of claims 5 to 15, characterized in that the basic module as a diesel engine Glühvonichtungen (19) only for the two outer cylinder.

17. Internal combustion engine according to one of claims 4 to 16, characterized in that the lifting piston (12) of the middle cylinder at the same cylinder heights a dead space (17) reducing, raised piston head (14).

18. Internal combustion engine according to one of claims 1 to 17, characterized that the crankshaft (4, 4 ') of the engine is also mounted between the connecting rod crankpins (5a, 5b, 5c).

19. An internal combustion engine according to at least one of the preceding claims, characterized in that valves (18, 27, 28, 31, 32, 59, 60) and the shut-off member (22, 23, 62) via the crankshaft [A, 4a; 54) of the engine are camshaft actuated.

20. An internal combustion engine according to any one of claims 5 to 19, characterized in that two basic modules (Al, A2) are provided in series, the offset by 180 ° to each other and their crankcase (55, 55 ') serve as charge pumps, wherein between the Charge pumps a connecting line [75] with means (74) for adjusting the passage cross-section of the connecting line (75).