DE102015211330A1 - Method for operating a exhaust-gas-charged internal combustion engine with partial deactivation and internal combustion engine for carrying out such a method - Google Patents

Abstract

Method for operating a supercharged internal combustion engine with min. a cylinder head comprising min. two cylinders (1, 2, 3, 4), in which - each cylinder (1, 2, 3, 4) min. an outlet opening (3b, 4b) and min. an inlet opening (3a1, 3a2, 4a1, 4a2) and has a piston, - min. an exhaust gas turbocharger is provided, - min. two cylinders (1, 2, 3, 4) are configured in such a way that these cylinders (1, 2, 3, 4) are min. two groups each with min. a cylinder (1, 2, 3, 4) form, wherein the min. a cylinder (1, 4) of a first group is a cylinder also in partial shutdown of the internal combustion engine in operation (1, 4) and the min. a cylinder (2, 3) of a second group is designed as a load-dependent switchable cylinder (2, 3), and - each inlet opening (3a1, 3a2, 4a1, 4a2) and each outlet opening (3b, 4b) of a cylinder (1, 2, 3, 4) is equipped with a valve drive with a valve which the associated opening (3a1, 3a2, 4a1, 4a2, 3b, 4b) blocks and releases, wherein - the min. an outlet opening (3b) of each deactivated cylinder (2, 3) of the second group is blocked by deactivating an associated at least partially variable valve train, - min. an inlet opening (3a1, 3a2) of a deactivated cylinder (2, 3) min. of a pair of cylinders is opened at the bottom dead center to moving piston in an intake stroke to supply the deactivated cylinder (2, 3) via the intake system (7) with charge air, and min. an inlet opening (3a1, 3a2) of this deactivated cylinder (2, 3) is opened in the context of a compression stroke after the piston has passed through the bottom dead center and before this piston reaches the top dead center, wherein the opening via the min. an inlet opening (3a1, 3a2) from the deactivated cylinder (2, 3) discharged charge air via overflow channel (8) to the operating cylinder (1, 4) of the cylinder pair is supplied.

Description

• – jeder Zylinder mindestens eine Auslassöffnung zum Abführen der Abgase via Abgasabführsystem und mindestens eine Einlassöffnung zum Zuführen von Ladeluft via Ansaugsystem aufweist und über einen Kolben verfügt, der entlang einer Kolbenlängsachse zwischen einem unteren Totpunkt UT und einem oberen Totpunkt OT bewegbar ist,
• – mindestens ein Abgasturbolader vorgesehen ist, der eine im Abgasabführsystem angeordnete Turbine und einen im Ansaugsystem angeordneten Verdichter umfasst,
• – mindestens zwei Zylinder in der Art konfiguriert sind, dass diese Zylinder mindestens zwei Gruppen mit jeweils mindestens einem Zylinder bilden, wobei der mindestens eine Zylinder einer ersten Gruppe ein auch bei Teilabschaltung der Brennkraftmaschine in Betrieb befindlicher Zylinder ist und der mindestens eine Zylinder einer zweiten Gruppe als lastabhängig schaltbarer Zylinder ausgebildet ist, und
• – jede Einlassöffnung und jede Auslassöffnung eines Zylinders mit einem Ventiltrieb ausgestattet ist mit einem Ventil, welches die zugehörige Öffnung versperrt und freigibt.

The invention relates to a method for operating a supercharged internal combustion engine having at least one cylinder head comprising at least two cylinders, in which

• Each cylinder has at least one outlet opening for discharging the exhaust gases via the exhaust gas removal system and at least one inlet opening for supplying charge air via the intake system and has a piston which is movable along a piston longitudinal axis between a bottom dead center UT and a top dead center OT,
• At least one exhaust-gas turbocharger is provided, which comprises a turbine arranged in the exhaust-gas removal system and a compressor arranged in the intake system,
• - At least two cylinders are configured in such a way that these cylinders form at least two groups each having at least one cylinder, wherein the at least one cylinder of a first group is also in partial deactivation of the internal combustion engine in operation cylinder and the at least one cylinder of a second group is designed as a load-dependent switchable cylinder, and
• - Each inlet opening and each outlet opening of a cylinder is equipped with a valvetrain with a valve which blocks and releases the associated opening.

Furthermore, the invention relates to a supercharged internal combustion engine for carrying out such a method.

An internal combustion engine of the type mentioned is used as a motor vehicle drive. In the context of the present invention, the term internal combustion engine includes diesel engines and gasoline engines, but also hybrid internal combustion engines, d. H. Internal combustion engines, which are operated with a hybrid combustion process, and hybrid drives, which in addition to the internal combustion engine include a drive motor-connectable with the electric motor, which receives power from the internal combustion engine or emits additional power as a switchable auxiliary drive.

Internal combustion engines have a cylinder block and at least one cylinder head, which are connected to form the individual cylinders.

Modern internal combustion engines are operated almost exclusively according to a four-stroke work process. As part of the change of charge, the combustion gases are pushed out via the outlet openings of the at least two cylinders and the charge air is filled via the inlet openings. In order to control the charge cycle, an internal combustion engine requires control means and actuators to operate these controls. To control the charge cycle, four-stroke engines use almost exclusively lift valves as control members which perform an oscillating lifting movement during operation of the internal combustion engine and in this way release and close the inlet openings and outlet openings. The required for the movement of a valve valve actuating mechanism including the valve itself is referred to as a valve train. The at least one cylinder head is generally used to accommodate this valve train.

It is the task of the valve drive to release the corresponding inlet opening or outlet opening of the cylinder in good time or to close, with a quick release of the largest possible flow cross section is sought to keep the throttle losses in the incoming and outflowing gas flows low and the best possible Filling the cylinder or an effective, d. H. To ensure complete removal of the exhaust gases. Therefore, the cylinders are also often equipped with multiple inlet openings and outlet openings.

The intake pipes leading to the intake ports and the exhaust pipes connecting to the exhaust ports are at least partially integrated in the cylinder head in the prior art. The intake lines of the cylinders are regularly merged into a common Gesamtansaugleitung or groups to several Gesamtansaugleitungen. The combination of intake manifolds to a total intake manifold is generally referred to as an intake manifold in the context of the present invention.

The cylinder block has a corresponding number of cylinder bores for receiving the pistons or the cylinder tubes. The piston of each cylinder of an internal combustion engine is axially movably guided in a cylinder tube and limits together with the cylinder tube and the cylinder head the combustion chamber of a cylinder. The piston serves to transfer the gas forces generated by the combustion to the crankshaft. For this purpose, the piston is articulated by means of a piston pin with a connecting rod, which in turn is movably mounted in the region of a Kurbelwellenkröpfung on the crankshaft. The crankshaft mounted in the crankcase receives the connecting rod forces, wherein the oscillating stroke movement of the piston is transformed into a rotating rotational movement of the crankshaft. The crankshaft transmits the torque to the drive train.

In the development of internal combustion engines, it is a fundamental goal to minimize fuel consumption. In this context, the charging of internal combustion engines is becoming increasingly important. The charge is a suitable means to increase the capacity of an internal combustion engine with unchanged displacement, or to reduce the displacement at the same power. In any case, the charging leads to an increase in space performance and a lower power mass. If the cubic capacity is reduced, the load spectrum can be shifted to higher loads at the same vehicle boundary conditions, where the specific fuel consumption is lower. The charging of an internal combustion engine thus supports the efforts to minimize fuel consumption, ie to improve the efficiency of the internal combustion engine.

Supercharged internal combustion engines are preferably equipped with a charge air cooling, with which the compressed combustion air is cooled before entering the cylinder. As a result, the density of the charge air supplied continues to increase. The cooling also contributes in this way to a compression and better filling of the combustion chambers, d. H. to an improved degree of filling, at. It may be advantageous to equip the intercooler with a bypass line in order to bypass the intercooler when necessary, for example, after a cold start.

The internal combustion engine object of the present invention is an internal combustion engine charged by turbocharging. The advantage of an exhaust gas turbocharger, for example in comparison to a mechanical supercharger, is that no mechanical connection is required for transmitting power between the supercharger and the internal combustion engine. While a mechanical supercharger obtains the energy required for its drive from the internal combustion engine and thus reduces the power provided and in this way adversely affects the efficiency, the exhaust gas turbocharger uses the exhaust gas energy of the hot exhaust gases.

The design of the exhaust turbocharger often causes difficulties, in principle, a noticeable increase in performance in all speed ranges is sought. However, a torque drop is regularly observed when falling below a certain speed. This torque drop becomes understandable if it is taken into account that the boost pressure ratio depends on the turbine pressure ratio. For example, if the engine speed is reduced, this leads to a smaller exhaust gas mass flow and thus to a smaller turbine pressure ratio. As a result, the boost pressure ratio and the charge pressure also decrease at lower speeds, which is equivalent to a torque drop.

Basically, the drop in charge pressure can be counteracted by a small exhaust gas turbocharger, d. H. an exhaust gas turbocharger with a small turbine cross section is used in order to generate a sufficient charge pressure even with small exhaust gas streams. Ultimately, the torque drop is thus shifted only to lower speeds. In addition, this approach, d. H. The reduction of the turbine cross-section limits, since the desired charging and performance should be possible even at high speeds without restriction and to the extent desired. A small design of the turbine cross-section in combination with a Abgasabblasung is not over the entire speed range expedient and satisfactory.

The torque characteristic of a supercharged internal combustion engine is attempted to be improved by different measures according to the prior art, for example by the use of a plurality of exhaust gas turbochargers arranged in series and / or in parallel; optionally in combination with one or more mechanical loaders and / or auxiliary electrical drives.

In the development of internal combustion engines, it is a fundamental goal to minimize fuel consumption, with an improved overall efficiency in the foreground of the efforts.

The fuel consumption and thus the efficiency are particularly problematic in gasoline engines, ie in spark-ignition internal combustion engines. The reason for this lies in the basic working method of the gasoline engine. The load control is usually carried out by means of a throttle valve provided in the intake system. By adjusting the throttle, the pressure of the intake air behind the throttle valve can be reduced more or less. The farther the throttle is closed, ie the more it obstructs the intake system, the higher is the pressure loss of the intake air across the throttle and the lower the pressure of the intake air downstream of the throttle and before the intake into the at least three cylinders, ie combustion chambers. With constant combustion chamber volume can be adjusted in this way on the pressure of the intake air, the air mass, ie the quantity. This also explains why the quantity control proves to be disadvantageous especially in partial load operation, because low loads require a high throttling and pressure reduction in the intake system, whereby the Charge change losses increase with decreasing load and increasing throttling.

In order to reduce the losses described, various strategies have been developed for de-throttling a spark-ignited internal combustion engine.

One approach to dethrottling the gasoline engine is, for example, an Otto engine working method with direct injection. The direct injection of the fuel is a suitable means for realizing a stratified combustion chamber charge. The direct injection of the fuel into the combustion chamber thus allows within certain limits a quality control of the gasoline engine. The mixture formation takes place by the direct injection of the fuel in the cylinders or in the air in the cylinders and not by external mixture formation, in which the fuel is introduced into the intake system in the intake air.

Another way to optimize the combustion process of a gasoline engine, is the use of an at least partially variable valve train. In contrast to conventional valve trains, in which both the stroke of the valves and the control times are not variable, these parameters influencing the combustion process and thus the fuel consumption can be varied more or less by means of variable valve trains. Throttle-free and thus lossless load control is already possible if the closing time of the intake valve and the intake valve lift can be varied. The mixture mass flowing into the combustion chamber during the intake process is then controlled not by means of a throttle valve but via the intake valve lift and the opening duration of the intake valve.

Another solution for de-throttling a gasoline engine offers the cylinder deactivation, d. H. the shutdown of individual cylinders in certain load ranges. The efficiency of the gasoline engine in partial load operation can be improved by a partial shutdown, d. H. be increased, because the shutdown of a cylinder of a multi-cylinder internal combustion engine increases the load of the remaining still in operation cylinder at constant engine power, so that the throttle for introducing a larger air mass in these cylinders can be opened or must, resulting in a total Entdrosselung the internal combustion engine is achieved. The continuously operating cylinders also operate during partial shutdown in the area of higher loads, where the specific fuel consumption is lower. The load collective is shifted to higher loads.

The further operated during the partial shutdown cylinder also have due to the larger air mass supplied or mixture mass improved mixture formation.

Further efficiency advantages result from the fact that a deactivated cylinder as a result of the lack of combustion no wall heat losses generated as a result of heat transfer from the combustion gases to the combustion chamber walls.

Although diesel engines, d. H. self-igniting internal combustion engines, due to the applied quality control originally higher efficiency, d. H. have a lower fuel consumption than gasoline engines, in which the load - as described above - is set by throttling or quantity control on the filling of the cylinder, there is also improvement potential for diesel engines and improvement in terms of fuel consumption and efficiency.

A concept for reducing fuel consumption is also the cylinder deactivation in diesel engines, d. H. the shutdown of individual cylinders in certain load ranges. The efficiency of the diesel engine in part load operation can be improved by a partial shutdown, d. H. be increased, because the shutdown of at least one cylinder of a multi-cylinder internal combustion engine increases at constant engine power even in the diesel engine, the load of the remaining operating cylinders, so that these cylinders operate in areas of higher loads, in which the specific fuel consumption is lower. The load collective in part-load operation of the diesel engine is shifted to higher loads.

With regard to the wall heat losses, the same advantages result as in the gasoline engine, for which reason reference is made to the corresponding explanations.

The partial shutdown in diesel engines should also prevent the fuel-air mixture under the quality scheme with decreasing load by reducing the amount of fuel used too much.

The multi-cylinder internal combustion engines with partial deactivation described in the prior art and the associated methods for operating these internal combustion engines nevertheless have clear potential for improvement.

If, for the purpose of partial shutdown, the fuel supply to the deactivatable cylinders is prevented, ie adjusted, the deactivated cylinders continue to participate in the charge exchange, if the associated valve drive of these cylinders does not is deactivated or can not be deactivated. The generated charge exchange losses reduce the improvements achieved by the partial shutdown in terms of fuel consumption and efficiency and counter this, so that the benefits of partial shutdown is at least partially lost, ie the partial shutdown in the sum actually brings a less significant improvement.

In order to remedy the disadvantageous effects described above, it can be expedient to provide switchable or adjustable valve drives on the inlet side and on the outlet side, with which the deactivated cylinders are kept closed during the partial shutdown and thus do not continue to take part in the charge exchange. This also prevents that guided by the deactivated cylinder cooler charge air reduces the enthalpy of the exhaust gas flow provided to the turbine and cool down the deactivated cylinders quickly.

Switchable valve trains, however, may lead to further problems in internal combustion engines charged by means of exhaust-gas turbocharging, such as the internal combustion engine which is the subject of the present invention, since the turbine of an exhaust-gas turbocharger is designed for a certain amount of exhaust gas and thus regularly also for a specific number of cylinders. If the valve drive of a deactivated cylinder is deactivated, initially the total mass flow through the cylinders of the internal combustion engine is reduced. The exhaust gas mass flow guided through the turbine decreases and, with this, as a rule, also the turbine pressure ratio. A decreasing turbine pressure ratio has the consequence that the boost pressure ratio also decreases, d. H. the boost pressure drops.

In fact, the boost pressure would have to be increased, d. H. be increased in order to supply the more in-service cylinders more charge air, because when switching off at least one cylinder of a multi-cylinder internal combustion engine, the load on the remaining still in operation cylinder increases, which is why these cylinders more charge air and more fuel is to be supplied. The drive power available at the compressor for generating a sufficiently high charge pressure depends on the exhaust gas enthalpy of the hot exhaust gases, which is largely determined by the exhaust pressure and the exhaust gas temperature, and the exhaust gas mass or the exhaust gas flow.

In gasoline engines, the boost pressure in the load range relevant for partial shutdown can be increased in a simple manner by opening the throttle valve. This option is omitted in the diesel engine. The low charge air flow may cause the compressor to operate beyond the surge line.

The effects described above lead to a limitation of the applicability of the partial shutdown, namely a restriction of the speed range and the load range in which the partial shutdown can be used. With small charge air quantities, the boost pressure can not be increased as needed due to an insufficient compressor power or turbine power.

The charge pressure at partial shutdown and thus the still in operation cylinders supplied charge air quantity could be increased, for example, by a small design of the turbine cross-section and simultaneous Abgasabblasung, whereby the relevant for a partial shutdown load range would be extended again. However, this approach has the disadvantage that the charging behavior is insufficient when all cylinders are operated.

In view of the foregoing, it is an object of the present invention to provide a method according to the preamble of claim 1, with which the partial shutdown is further optimized.

Another object of the present invention is to provide a supercharged internal combustion engine for carrying out such a method.

• – jeder Zylinder mindestens eine Auslassöffnung zum Abführen der Abgase via Abgasabführsystem und mindestens eine Einlassöffnung zum Zuführen von Ladeluft via Ansaugsystem aufweist und über einen Kolben verfügt, der entlang einer Kolbenlängsachse zwischen einem unteren Totpunkt UT und einem oberen Totpunkt OT bewegbar ist,
• – mindestens ein Abgasturbolader vorgesehen ist, der eine im Abgasabführsystem angeordnete Turbine und einen im Ansaugsystem angeordneten Verdichter umfasst,
• – mindestens zwei Zylinder in der Art konfiguriert sind, dass diese Zylinder mindestens zwei Gruppen mit jeweils mindestens einem Zylinder bilden, wobei der mindestens eine Zylinder einer ersten Gruppe ein auch bei Teilabschaltung der Brennkraftmaschine in Betrieb befindlicher Zylinder ist und der mindestens eine Zylinder einer zweiten Gruppe als lastabhängig schaltbarer Zylinder ausgebildet ist, und
• – jede Einlassöffnung und jede Auslassöffnung eines Zylinders mit einem Ventiltrieb ausgestattet ist mit einem Ventil, welches die zugehörige Öffnung versperrt und freigibt, das dadurch gekennzeichnet ist, dass die Zylinder in der Art gruppiert sind, dass jeweils zwei Zylinder ein Zylinderpaar bilden, welches einen Zylinder der ersten Gruppe und einen Zylinder der zweiten Gruppe umfasst, und während der Teilabschaltung
• – die mindestens eine Auslassöffnung jedes abgeschalteten Zylinders der zweiten Gruppe versperrt wird, indem ein zugehöriger zumindest teilweise variabler Ventiltrieb deaktiviert wird,
• – mindestens eine Einlassöffnung eines abgeschalteten Zylinders mindestens eines Zylinderpaares bei sich auf den unteren Totpunkt zu bewegendem Kolben im Rahmen eines Ansaugtaktes geöffnet wird, um den abgeschalteten Zylinder via Ansaugsystem mit Ladeluft zu versorgen, und mindestens eine Einlassöffnung dieses abgeschalteten Zylinders im Rahmen eines Kompressionstaktes geöffnet wird, nachdem der Kolben den unteren Totpunkt durchlaufen hat und bevor dieser Kolben den oberen Totpunkt erreicht, wobei die beim Öffnen via der mindestens einen Einlassöffnung aus dem abgeschalteten Zylinder abgeführte Ladeluft via Überströmkanal dem in Betrieb befindlichen Zylinder des Zylinderpaares zugeführt wird.

The first sub-problem is solved by a method for operating a supercharged internal combustion engine having at least one cylinder head comprising at least two cylinders, in which

• Each cylinder has at least one outlet opening for discharging the exhaust gases via the exhaust gas removal system and at least one inlet opening for supplying charge air via the intake system and has a piston which is movable along a piston longitudinal axis between a bottom dead center UT and a top dead center OT,
• At least one exhaust-gas turbocharger is provided, which comprises a turbine arranged in the exhaust-gas removal system and a compressor arranged in the intake system,
• - At least two cylinders are configured in such a way that these cylinders form at least two groups each having at least one cylinder, wherein the at least one cylinder of a first group is also in partial deactivation of the internal combustion engine in operation cylinder and the at least one cylinder of a second group is designed as a load-dependent switchable cylinder, and
• Each inlet and outlet of a cylinder is equipped with a valvetrain having a valve which blocks and releases the associated orifice, characterized in that the cylinders are grouped in such a way that two cylinders each constitute a pair of cylinders constituting a cylinder the first group and a cylinder of the second group, and during the partial shutdown
• - the at least one outlet opening of each deactivated cylinder of the second group is blocked by an associated at least partially variable valve train is deactivated,
• - At least one inlet opening of a deactivated cylinder of at least one pair of cylinders is opened at the bottom dead center to moving piston in an intake stroke to supply the deactivated cylinder via intake system with charge air, and at least one inlet opening of this deactivated cylinder is opened in the context of a compression stroke After the piston has passed through the bottom dead center and before this piston reaches the top dead center, wherein the discharged during opening via the at least one inlet opening from the deactivated cylinder charge air is supplied via overflow to the in-service cylinder of the cylinder pair.

According to the method of the invention, a deactivated cylinder is diverted during the partial shutdown and used as a pump to provide at least one further in-service cylinder additional charge air and supply.

By this measure, the applicability of the partial shutdown to low speeds and low loads expand or expand. According to the invention, the amount of charge air supplied to the cylinders which are still in operation during partial shutdown no longer depends exclusively on the available compressor power or the charge pressure that can be generated by the compressor. Rather, the amount of charge air supplied to a cylinder in operation is increased or adjusted as required by means of a deactivated cylinder.

For this purpose, cylinder pairs are formed, wherein according to the invention in each case one cylinder of the first group, d. H. a cylinder which continues to operate at partial shutdown, and a cylinder of the second group, d. H. a deactivated at Teilabschaltung cylinder, form a pair of cylinders. The deactivated cylinder of the second group is used during the partial shutdown as Ladeluftlieferder cylinder which provides the operating cylinder of the first group additional charge air, which is why the latter cylinder is also referred to as a charge air-receiving cylinder and considered.

An overflow passage is provided which connects at least one inlet port of the charge air receiving cylinder to at least one inlet port of the charge air delivering cylinder to introduce charge air via the transfer port from the deactivated charge air delivering cylinder into the charge air receiving in-service cylinder of the cylinder pair.

In the case of the internal combustion engine according to the invention, each outlet opening of a deactivatable cylinder of the second group is equipped with an at least partially variable valvetrain whose exhaust valve is at least switchable or can be switched off in order to deactivate the associated outlet opening of the deactivated cylinder during partial shutdown, d. H. keep closed, so that the charge air introduced into the deactivated cylinder is not escaped or discharged on the outlet side.

The intake-side transfer of charge air from a charge air-supplying cylinder into a charge air-receiving cylinder requires, in addition to an overflow channel, a coordinated opening and closing of the relevant intake openings of both the deactivated charge-supplying cylinder and the charge air-receiving operating cylinder, the charge air-receiving cylinder preferably being used with those used in normal operation, d. H. unchanged tax hours is operated.

First, at least one inlet opening of a deactivated cylinder is opened in the context of an intake stroke when the piston is moving toward bottom dead center in order to introduce or suck in charge air into the deactivated cylinder via the intake system. In the context of the subsequent compression stroke, at least one inlet opening of the deactivated cylinder is then opened, wherein the piston, which is to be moved to the top dead center, compresses the charge air sucked in and expands at least one inlet opening from the deactivated cylinder and via the overflow channel to the cylinder in operation the cylinder pair supplies.

Pumping the compressor can be prevented. The load range in which the partial shutdown can be used effectively is extended. The torque characteristic of the supercharged internal combustion engine during partial shutdown is significantly improved.

With the method according to the invention a method according to the preamble of claim 1 is shown, with the partial shutdown is further optimized. The method according to the invention thus solves the first sub-task on which the invention is based.

The internal combustion engine according to the invention has at least two cylinders or at least two groups each having at least one cylinder. In this respect, internal combustion engines with three cylinders configured in two groups or in three groups with one cylinder each, or internal combustion engines with six cylinders configured in three groups with two cylinders each are also internal combustion engines according to the invention. The three cylinder groups can be successively switched on or off as part of a partial shutdown, whereby a two-time switching can be realized. The partial shutdown is thereby further optimized. The cylinder groups may also comprise a different number of cylinders.

In the internal combustion engine according to the invention cylinder pairs are formed. It should be noted that a deactivated cylinder not only a pair of cylinders, but more than one pair of cylinders, for example, two pairs of cylinders, may belong to and as a charge air delivering cylinder more than a charge air receiving cylinder additional charge air available.

Further advantageous embodiments of the method according to the invention are discussed in connection with the subclaims.

The point in time at which the at least one inlet opening of the deactivated cylinder is opened in the context of the compression stroke depends on a number of influencing factors.

On the one hand, whether the intercooler cylinder has more than one inlet opening and how many inlet openings are connected to the charge air-receiving cylinder via the overflow channel. If, for example, the charge-supplying cylinder has two inlet openings, of which only one inlet opening is connected to the charge-air-receiving cylinder via the overflow channel, the other inlet opening should be closed before the opening of this inlet opening as part of the compression stroke so that the charge air only escapes via the overflow channel or can be dissipated.

On the other hand, the point in time at which the at least one inlet opening of the deactivated cylinder is opened within the scope of the compression stroke also depends on how great the mechanical or thermodynamic offset of the two cylinders of the cylinder pair is, ie. H. for example, if this offset is 90, 120, 180, 240 or 360 ° CA In this respect, both the Kurbelwellenkröpfung and the firing order of importance with regard to the grouping of the cylinder.

Embodiments of the method are advantageous, for example, in which the at least one inlet opening of the deactivated cylinder is opened later than 35 ° CA after bottom dead center UT in the context of the compression stroke.

Embodiments of the method may also be advantageous in which the at least one inlet opening of the deactivated cylinder is opened later than the bottom dead center UT within the scope of the compression stroke, later than 50 ° CA.

Also advantageous are embodiments of the method in which the at least one inlet opening of the deactivated cylinder is opened later than 70 ° CA after the bottom dead center UT within the scope of the compression stroke.

Embodiments of the method may also be advantageous in which the at least one inlet opening of the deactivated cylinder is opened later than 90 ° CA after bottom dead center UT in the context of the compression stroke.

Furthermore, embodiments of the method are advantageous in which the at least one inlet opening of the deactivated cylinder is opened later than 110 ° CA after the bottom dead center UT in the context of the compression cycle.

Advantageous embodiments of the method in which the at least one inlet opening of the deactivated cylinder is closed in the context of the compression stroke before the piston reaches the top dead center TDC. This prevents the piston passing through the top dead center from colliding with an open inlet valve.

For operating internal combustion engines in which each valve obstructs or releases the associated opening, wherein an actuating oscillating valve between an open position and a closed position forms a valve lift .DELTA.h and the opening during an opening duration .DELTA.t releases are - also for the above-mentioned reasons - Process variants advantageous, which are characterized in that formed in the context of the intake stroke valve lift .DELTA.h is _at least three times greater than the valve formed _in the context of the compression stroke .DELTA.h _comp , preferably with .DELTA.h _in / .DELTA.h _comp ≥ 4 and with .DELTA.h _in / .DELTA.h _comp ≥ 5 or with Δh _in / Δh _comp ≥ 7. The same applies to the opening duration Δt.

The above-set valve lifts Δh _in , Δh _comp need not be performed by the same intake valve.

A charge-supplying cylinder, ie a cylinder of the second group, may have an inlet opening, which then serves both to draw in charge air during the intake stroke and to discharge this charge air via an overflow passage in the course of the compression stroke.

However, a charge-supplying cylinder may also have more than one inlet opening. Then all the inlet openings can serve for the intake of charge air in the context of the intake stroke and / or the discharge of this charge air via overflow in the context of the compression stroke, but also only one inlet opening or a limited number or selection of inlet openings.

In this respect, there are also different process variants relating to these at least one inlet opening of the intercooler, which will be briefly set forth below.

For operating an internal combustion engine, in which each cylinder of the second group has two inlet openings for supplying charge air via intake system, process variants may be advantageous, which are characterized in that during the partial shutdown a first inlet opening of a deactivated cylinder at least one pair of cylinders with at the bottom Totpunkt to moving piston is opened in the context of an intake stroke to supply the deactivated cylinder via the intake system with charge air, and a second inlet port of this deactivated cylinder is opened in a compression stroke after the piston has passed through the bottom dead center and before this piston the upper Dead center reached, wherein the opening via the second inlet opening discharged from the deactivated cylinder charge air via overflow to the operating cylinder of the cylinder pair is supplied.

In the present case, the charge-supplying cylinder, d. H. the cylinder of the second group, two inlet openings, one of which inlet port serves for the intake of charge air in the context of the intake stroke and another inlet port for discharging this charge air via overflow in the compression stroke.

For operating an internal combustion engine, in which each cylinder of the second group has at least two inlet openings for supplying charge air via intake system, process variants may be advantageous, which are characterized in that during partial shutdown all inlet openings of a deactivated cylinder at least one pair of cylinders with at the bottom Dead center to moving piston to be opened in the context of an intake stroke to supply the deactivated cylinder via the intake system with charge air, and an inlet opening of this deactivated cylinder is opened in a compression stroke after the piston has passed through the bottom dead center and before this piston top dead center achieved, wherein the opening via the inlet opening discharged from the deactivated cylinder charge air via overflow to the operating cylinder of the cylinder pair is supplied.

In the present case, the charge-supplying cylinder, d. H. the cylinder of the second group, more than one inlet opening, namely at least two inlet openings, wherein all inlet openings are used for the intake of charge air in the context of the intake stroke and only one inlet opening for the discharge of this charge air is used in the compression stroke.

For operating an internal combustion engine, in which each cylinder of the second group has at least two inlet openings for supplying charge air via intake system, process variants may be advantageous, which are characterized in that during partial shutdown all inlet openings of a deactivated cylinder at least one pair of cylinders with at the bottom Totpunkt to moving piston in an intake stroke are opened to supply the deactivated cylinder via the intake system with charge air, and all the inlet openings of this deactivated cylinder are opened in a compression stroke after the piston has passed through the bottom dead center and before this piston top dead center achieved, wherein the opening via the inlet openings discharged from the deactivated cylinder charge air via overflow to the operating cylinder of the cylinder pair is supplied.

In the present case, all inlet openings of a cylinder supplying the charge air, i. H. a cylinder of the second group, both the intake of charge air in the context of the intake stroke and the discharge of this charge air in the context of the compression stroke.

Embodiments of the method in which the overflow channel is at least formed by the intake system are advantageous, wherein the overflow channel connects the at least one inlet opening of the deactivated cylinder, which is opened during the compression stroke, with the cylinder of the cylinder pair in operation and at least during the compression cycle from the remaining intake system is detachable channel.

Be - as described above - already existing components, namely the Intake system and an intake manifold and the inlet valves, used to form the overflow and provide necessary shut-off elements, components, weight and space and thus costs can be saved. In particular, the inlet valves can be used to release the overflow on both sides and obstruct. The overflow channel must connect at least one inlet opening of the deactivated cylinder to at least one inlet opening of the cylinder in operation of the cylinder pair and not necessarily continuously, but at least temporarily, namely at least during the compression stroke with open or shared overflow. Consequently, the overflow channel must be a detachable from the rest of the intake system at least during the compression stroke channel.

If the overflow channel can be connected to the remainder of the intake system, the at least one inlet opening of the deactivated, off-set cylinder, which is opened in the course of the compression stroke for the purpose of transferring charge air, can also be used to draw in charge air during the intake stroke.

Embodiments of the method are advantageous in which at least one inlet opening of the cylinder in operation of the at least one pair of cylinders is opened in order to introduce the charge air discharged from the deactivated cylinder into the cylinder in operation. If appropriate, this at least one inlet opening of the cylinder in operation is already open or opened when the at least one inlet opening of the switched-off cylinder delivering the charge air is opened in the context of the compression stroke for the purpose of transferring charge air.

Embodiments of the method are advantageous in which at least one inlet opening of the cylinder in operation of the at least one pair of cylinders is opened in the course of an intake stroke with the piston to be moved to the bottom dead center in order to deliver the charge air discharged from the deactivated cylinder into the cylinder in operation contribute. Then, the at least one inlet opening of the operating cylinder is opened during the suction, whereby the transfer of charge air is assisted.

A charge air receiving cylinder, d. H. a cylinder of the first group, may have an inlet port which is connected to the charge air delivering cylinder to transfer charge air in the context of the compression stroke.

However, a charge-air-receiving cylinder may also have more than one inlet opening. Then, all the intake ports can be connected to the charge-supplying cylinder, but also only one intake port or a limited number or selection of intake ports.

In this respect, there are also different process variants relating to these at least one inlet opening of the charge air-receiving cylinder, which will be briefly set forth below.

For operating an internal combustion engine, in which each cylinder of the first group has at least two inlet openings for supplying charge air via intake system, process variants may be advantageous, which are characterized in that during the partial shutdown an inlet opening of the operating cylinder of the at least one pair of cylinders via overflow is connected to the deactivated cylinder to introduce the discharged from the deactivated cylinder charge air in the operating cylinder.

In this context, embodiments of the method are advantageous in which the at least one other inlet opening of the cylinder in operation of the at least one pair of cylinders, which is not connected via the overflow channel with the deactivated cylinder is closed before the charge air discharged from the deactivated cylinder in the in Operating cylinder is introduced.

For operating an internal combustion engine in which each cylinder of the first group has at least two inlet openings for supplying charge air via intake system, process variants may be advantageous, which are characterized in that during partial shutdown all inlet openings of an operating cylinder of the cylinder pair via overflow with the disconnected cylinder are connected to bring the discharged from the deactivated cylinder charge air in the operating cylinder.

The second sub-task on which the invention is based, namely to provide an internal combustion engine for carrying out a method of the type described above, is achieved with a supercharged internal combustion engine having at least one cylinder head comprising at least two cylinders, in which

• – mindestens ein Abgasturbolader vorgesehen ist, der eine im Abgasabführsystem angeordnete Turbine und einen im Ansaugsystem angeordneten Verdichter umfasst,
• – mindestens zwei Zylinder in der Art konfiguriert sind, dass diese Zylinder mindestens zwei Gruppen mit jeweils mindestens einem Zylinder bilden, wobei der mindestens eine Zylinder einer ersten Gruppe ein auch bei Teilabschaltung der Brennkraftmaschine in Betrieb befindlicher Zylinder ist und der mindestens eine Zylinder einer zweiten Gruppe als lastabhängig schaltbarer Zylinder ausgebildet ist, und
• – jede Einlassöffnung und jede Auslassöffnung eines Zylinders mit einem Ventiltrieb ausgestattet ist mit einem Ventil, welches die zugehörige Öffnung versperrt und freigibt, wobei die mindestens eine Auslassöffnung jedes abschaltbaren Zylinders der zweiten Gruppe mit einem abschaltbaren Ventiltrieb ausgestattet ist, und die dadurch gekennzeichnet ist, dass
• – die Zylinder in der Art gruppiert sind, dass jeweils zwei Zylinder ein Zylinderpaar bilden, welches einen Zylinder der ersten Gruppe und einen Zylinder der zweiten Gruppe umfasst, wobei der Zylinder der zweiten Gruppe als ladeluftliefernder Zylinder dem Zylinder der ersten Gruppe als ladeluftempfangenden Zylinder während der Teilabschaltung zusätzliche Ladeluft bereitstellt, wozu ein zumindest zeitweise ausbildbarer Überströmkanal vorgesehen ist, der mindestens eine Einlassöffnung des ladeluftempfangenden Zylinders mit mindestens einer Einlassöffnung des ladeluftliefernden Zylinders verbindet, um Ladeluft via dem Überströmkanal aus dem abgeschalteten ladeluftliefernden Zylinder in den ladeluftempfangenden in Betrieb befindlichen Zylinder des Zylinderpaares einzubringen.

Each cylinder has at least one outlet opening for discharging the exhaust gases via the exhaust gas removal system and at least one inlet opening for supplying charge air via the intake system and has a piston which is movable along a piston longitudinal axis between a bottom dead center UT and a top dead center OT,

• At least one exhaust-gas turbocharger is provided, which comprises a turbine arranged in the exhaust-gas removal system and a compressor arranged in the intake system,
• - At least two cylinders are configured in such a way that these cylinders form at least two groups each having at least one cylinder, wherein the at least one cylinder of a first group is also in partial deactivation of the internal combustion engine in operation cylinder and the at least one cylinder of a second group is designed as a load-dependent switchable cylinder, and
• Each inlet opening and each outlet opening of a cylinder is equipped with a valvetrain having a valve which blocks and releases the associated opening, wherein the at least one outlet opening of each deactivatable cylinder of the second group is equipped with a deactivatable valvetrain, and which is characterized in that
• - The cylinders are grouped in such a way that each two cylinders form a pair of cylinders, comprising a cylinder of the first group and a cylinder of the second group, wherein the cylinder of the second group as a charge air-supplying cylinder to the cylinder of the first group as a charge air-receiving cylinder during the Partial shutdown provides additional charge air, for which an at least temporarily formable overflow channel is provided which connects at least one inlet opening of the charge air-receiving cylinder with at least one inlet opening of the intercooler cylinder to introduce charge air via the overflow from the switched off intercooler cylinder in the charge air receiving in-service cylinder of the cylinder pair ,

What has already been said for the method according to the invention also applies to the internal combustion engine according to the invention, which is why reference is generally made at this point to the statements made above with regard to the method. The various internal combustion engines sometimes require different process variants.

Embodiments of the supercharged internal combustion engine in which the intake system forms the overflow channel at least are advantageous, wherein the overflow channel is designed as a channel which can be separated from the intake system and which can also be connected to the intake system by actuating a shut-off element via at least one opening.

The overflow channel can be formed by walls of the intake system or of the intake manifold. Optionally, the method of the invention requires additional walls to be introduced into the intake system or intake manifold, i. H. are to be incorporated.

The overflow channel must - as already mentioned - be a detachable from the rest of the intake system at least during the compression stroke channel. It is advantageous if the overflow channel can be connected to the rest of the intake system and the at least one inlet opening of the switched off off-loading cylinder, which is opened in the context of the compression stroke for the purpose of transferring charge air, also for the intake of charge air in the intake stroke. This applies in particular for the normal operation of the internal combustion engine after completion of the partial shutdown. Then the deactivatable cylinder is at least one more inlet opening for the change of charge available. The at least one shut-off element releases the at least one opening or blocks this opening and can be designed, for example, as a flap.

Embodiments of the supercharged internal combustion engine in which the two cylinders of a cylinder pair are each adjacent to each other in the cylinder arranged at least one cylinder head are advantageous. The local proximity of the two cylinders of a pair of cylinders, d. H. its geometric proximity has advantages for the method according to the invention and the internal combustion engine according to the invention, since the distance between an inlet opening of the charge-air-receiving cylinder and an inlet opening of the charge-air-supplying cylinder is shortened. The overflow channel is structurally simpler, is less long and less bulky. In particular, the latter supports the transfer of charge air from the charge-supplying cylinder in the charge air-receiving cylinder.

Embodiments of the supercharged internal combustion engine having at least one cylinder head and four cylinders arranged in series along the longitudinal axis of the at least one cylinder head are advantageous, of which the two outer cylinders are also cylinders of the first group in operation during partial shutdown of the internal combustion engine and the two inner cylinders can be switched depending on the load Cylinders of the second group are, which are characterized in that in each case an outboard cylinder and the adjacent inner cylinder form a pair of cylinders.

When the internal combustion engine is operated with the ignition sequence 1-3-4-2, the ignition times in ° CA measured are the following: 0-180-360-540. During partial shutdown, the outboard cylinders in operation, i. H. the first and the fourth cylinder, a thermodynamic offset of 360 ° KW.

The deactivated third cylinder serves as a charge-delivering cylinder for the fourth cylinder, which is a charge air-receiving cylinder as an in-service cylinder. And the second cylinder serves as a charge-delivering cylinder for the first cylinder, which is also a charge air-receiving cylinder. The cylinders of the two pairs of cylinders then have a mechanical offset of 180.degree. CA, each with a corresponding crankshaft offset. If a cylinder supplying the charge air is in compression, the associated charge air receiving cylinder sucks simultaneously.

In supercharged internal combustion engines, in which each cylinder has two inlet openings for supplying charge air via intake system, embodiments are advantageous, which are characterized in that in each case the inlet opening of a disengageable cylinder of a pair of cylinders, which are also in partial shutdown of the engine in operation cylinder of this pair of cylinders is facing, via overflow with the inlet opening of the cylinder of the pair of cylinders which is also in partial shutdown of the internal combustion engine in operation, which faces the turn-off cylinder of the cylinder pair is connectable.

Above, the opposite inlet openings of the cylinder of a pair of cylinders are connected to each other or these inlet openings are connected to each other via overflow. As a result, the distance between the cylinders of a cylinder pair is shortened as far as possible and the length of the overflow is minimized.

Advantageous embodiments of the supercharged internal combustion engine, in which each cylinder is equipped for introducing fuel with a direct injection.

Embodiments in which each cylinder is equipped with an injection nozzle for the purpose of direct injection are advantageous.

The fuel supply can be deactivated faster and more reliable for the purpose of partial shutdown in direct-injection internal combustion engines as in internal combustion engines with intake manifold injection, in which fuel residues in the intake manifold can lead to unwanted burns in the deactivated cylinder.

Nevertheless, embodiments of the internal combustion engine may be advantageous in which for the purpose of a fuel supply, a port injection is provided.

Embodiments of the supercharged internal combustion engine in which at least two exhaust-gas turbochargers are provided, each of which comprises a turbine arranged in the exhaust-gas removal system and a compressor arranged in the intake system, are advantageous.

The torque characteristic of a supercharged internal combustion engine may be increased by a plurality of turbochargers arranged in parallel, i. H. be improved by a plurality of parallel turbines of smaller turbine cross-section, with successively switched turbines with increasing exhaust gas quantity; similar to a register charge.

The torque characteristic can also be advantageously influenced by means of a plurality of exhaust-gas turbochargers connected in series. By switching in series of two exhaust gas turbochargers, one of which is an exhaust gas turbocharger as a high pressure stage and an exhaust gas turbocharger as a low pressure stage, the map can be widened in an advantageous manner, both towards smaller compressor streams and towards larger compressor streams.

In the following the invention is based on two embodiments of the supercharged internal combustion engine and according to the 1 . 2a . 2 B and 3 explained in more detail. Hereby shows:

1 schematically and fragmentarily a first embodiment of the internal combustion engine in normal operation, partially cut,

2a schematically and fragmentarily the in 1 illustrated internal combustion engine during the partial shutdown, partially cut,

2 B in a diagram, the valve lift curves of the intake valves of the third cylinder of the in 1 during the partial shutdown and the valve lift curve of the intake valves of the fourth cylinder, and

3 schematically and fragmentarily a second embodiment of the internal combustion engine, partially cut.

1 shows schematically and fragmentarily a first embodiment of the internal combustion engine in normal operation, partially cut.

It is a four-cylinder in-line engine with direct injection, in which the four cylinders 1 . 2 . 3 . 4 along the longitudinal axis of the cylinder head, ie arranged in series, and each equipped with an injector for injecting fuel (not shown).

Every cylinder 1 . 2 . 3 . 4 has two inlet openings 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ for supplying charge air via intake system 7 on, taking on each inlet port 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ an intake pipe 5a ₁ , 5a ₂ , 6a ₁ , 6a ₂ connects. The suction lines 5a ₁ , 5a ₂ , 6a ₁ , 6a ₂ lead to the formation of an intake manifold 7 to a total suction line together. To exhaust the exhaust gases via Abgasabführsystem is every cylinder 1 . 2 . 3 . 4 with two outlet openings 3b . 4b fitted. In addition, each cylinder has 1 . 2 . 3 . 4 via a piston which is movable along a piston longitudinal axis between a bottom dead center UT and a top dead center OT (not shown).

For the purpose of charging, the internal combustion engine is equipped with at least one exhaust-gas turbocharger, which has a turbine arranged in the exhaust-gas removal system and one in the intake system 7 arranged compressor comprises.

The four cylinders 1 . 2 . 3 . 4 are configured and form two groups with two cylinders each 1 . 2 . 3 . 4 , where the two outer cylinders 1 . 4 form a first group whose cylinder 1 . 4 are also in partial shutdown of the internal combustion engine in operation, and the two inner cylinder 2 . 3 form a second group whose cylinder 2 . 3 as a load-dependent switchable cylinder 2 . 3 are formed, which are turned off in the context of a partial shutdown.

Each inlet opening 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ and each outlet opening 3b . 4b is equipped with a valvetrain comprising a valve which has the associated opening 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ , 3b . 4b locks and releases, with the two outlet openings 3b every disconnectable cylinder 2 . 3 the second group are equipped with a switchable valve train.

The four cylinders 1 . 2 . 3 . 4 are further grouped in the way that each two cylinders 1 . 2 . 3 . 4 form a cylinder pair, which is a cylinder 1 . 4 the first group and a cylinder 2 . 3 the second group, wherein the cylinder 2 . 3 the second group as a load-delivering cylinder 2 . 3 the cylinder 1 . 4 the first group as a cargo-receiving cylinder 1 . 4 during partial shutdown provides additional charge air. In each case an external cylinder 1 . 4 and the adjacent inner cylinder 2 . 3 form a cylinder pair.

To transfer charge air is one from the rest of the intake system 7 detachable overflow channel 8th provided, in the present case the first inlet opening 4a _{1 of} the charge air receiving fourth cylinder 4 with the second inlet opening 3a _{2 of} the intercooler third cylinder 3 connects or during the partial shutdown can connect to charge air via the overflow 8th from the deactivated intercooler third cylinder 3 in the in-service charge air receiving fourth cylinder 4 of the cylinder pair to bring.

2a shows schematically and fragmentarily the in 1 shown internal combustion engine during the partial shutdown, partially cut. It should only be supplementary to 1 For that reason, reference is made to FIG 1 , The same reference numerals have been used for the same parts.

During partial shutdown, the outlet openings become 3b of the deactivated third cylinder 3 the second group blocked by the associated at least partially variable valve trains are disabled.

The first inlet opening 3a _{1 of} the deactivated third cylinder 3 is opened at the bottom dead center to moving piston in the context of an intake stroke to the deactivated third cylinder 3 via intake system 7 and first suction line 5a ₁ with charge air supply (see also 2 B - EV _3,1 ). Subsequently, the second inlet opening 3a _{2 of} this disabled third cylinder 3 in the context of the following compression stroke - with closed first inlet opening 3a ₁ - opened after the piston has passed through the bottom dead center and before this piston reaches top dead center (see also 2 B - EV _3.2 ). In this case, the opening of the second inlet opening 3a ₂ from the deactivated third cylinder 3 discharged charge air via overflow channel 8th the fourth cylinder in operation 4 supplied to the cylinder pair (see also 2 B - EV ₄ ).

The intake system 7 forms the overflow channel 8th in the present case, with additional walls in the intake system 7 or the intake manifold 7 are incorporated. The overflow channel 8th must be at least during the compression stroke of the remaining intake system 7 be separable channel. The overflow channel 8th but can also be during the entire partial shutdown of the rest of the intake system 7 be separable or a separate channel (see 2a ).

Can the overflow channel 8th - As in the present case - with the rest of the intake system 7 by actuating a shut-off element 8b via an opening 8a connect (see also 1 ), the second inlet opening 3a _{2 of} the deactivated intercooler third cylinder 3 , which is opened in the context of the compression stroke for the purpose of transferring charge air, can also be used to draw in charge air during the intake stroke. Then there is the disable cylinder 3 another inlet opening 3a ₂ for the suction or the charge change available. This is particularly an advantage in normal operation of Internal combustion engine and indeed for the fourth cylinder 4 , which then also another inlet opening 4a _{1 is available} for the charge change (see also 1 ).

2 B shows in a diagram the valve lift curves EV _3.1 , EV _{3.2 of} the intake valves of the third cylinder 3 the in 1 shown internal combustion engine during the partial shutdown and the valve lift curve EV _{4 of} the intake valves of the fourth cylinder 4 ,

The valve lift Δh _in , which in the context of the intake stroke from the inlet valve of the first inlet opening 3a _{1 of} the third cylinder 3 is formed, is more than seven times greater than the valve lift .DELTA.h _comp , in the context of the compression stroke from the inlet valve of the second inlet port 3a _{2 of} the third cylinder 3 is trained.

Also indicated are the top dead center OT _{3 of} the third cylinder and the top dead center OT _{4 of} the fourth cylinder.

3 shows schematically and fragmentarily a second embodiment of the internal combustion engine, partially cut. It should only be carried out in addition to the preceding figures, which is why reference is otherwise made to the preceding statements.

It is a three-cylinder in-line engine in which the three cylinders 11 . 12 . 13 along the longitudinal axis of the cylinder head, that are arranged in series. Every cylinder 11 . 12 . 13 has two inlet openings 11a ₁ , 11a ₂ , 12a ₁ , 12a ₂ 13a ₁ , 13a ₂ for supplying charge air via intake system 7 on, being attached to each inlet opening 11a ₁ , 11a ₂ , 12a ₁ , 12a ₂ 13a ₁ , 13a ₂ connects a suction line. The intake pipes lead into a plenum 14 and forming an intake manifold 7 to a total intake pipe 7a together.

The three cylinders 11 . 12 . 13 are configured and form two groups, the two outer cylinders 11 . 13 form a first group whose cylinder 11 . 13 are also in partial shutdown of the internal combustion engine in operation, and the inner cylinder 12 forms a second group, ie as a load-dependent switchable cylinder 12 is formed, which is turned off in the context of a partial shutdown.

The three cylinders 11 . 12 . 13 are further grouped in the way that each two cylinders 11 . 12 . 13 form a pair of cylinders, with a pair of cylinders a cylinder 11 . 13 the first group and a cylinder 12 of the second group. The deactivated cylinder 12 the second group represents as a charge-delivering cylinder 12 two cylinders 11 . 13 the first group as cargo-receiving cylinders 11 . 13 additional charge air ready during partial shutdown. The internal deactivated cylinder 12 belongs in the present case more than one pair of cylinders, namely two pairs of cylinders, and provides as a charge air delivering cylinder 12 the two outer cylinders 11 . 13 as a charge air receiving cylinders 11 . 13 alternating additional charge air available.

To transfer charge air is one from the rest of the intake system 7 detachable overflow channel 8th provided in this Chamber by the plenary 14 of the intake system 7 is formed with and at least the first inlet opening 11a ₁ , 13a _{1 of} a charge air receiving cylinder 11 . 13 with the second inlet opening 12a _{2 of} the intercooler second cylinder 1 connects or during the partial shutdown can connect to charge air via the overflow 8th from the disconnected second intercooler 12 into an in-service charge air receiving cylinder 11 . 13 of the cylinder pair to bring.

The overflow channel 8th is also at the in 3 illustrated embodiment during the compression stroke from the rest of the intake system 7 detachable channel. For this purpose is a shut-off 8b serving check valve 8c in the total intake pipe 7a arranged, which the overflow from the rest of the intake system 7 can disconnect, ie for the intake of charge air in the context of the intake stroke opens and closes in the context of compression stroke for the purpose of transferring charge air.

The three-cylinder in-line engine can be equipped with a crankshaft whose three crankshaft cranks are arranged circumferentially offset by 120 ° on the crankshaft, the ignition in the cylinders 11 . 12 . 13 initiated at a distance of 240 ° KW.

The crankshaft cranks of the three cylinders 11 . 12 . 13 but can also be arranged offset by 180 ° to each other on the crankshaft, wherein the Kurbelwellenkröpfung of the inner cylinder 12 opposite the crankshaft cranks of the outboard cylinders 11 . 13 offset in the circumferential direction by 180 ° on the crankshaft. The cylinders can be ignited in the order 3-2-1, so that starting from the third cylinder the ignition times of the three cylinders measured in ° KW are the following: 0-180-360. The re-ignition of the third cylinder is initiated at 720 ° CA. When partial shutdown results in a firing interval of 360 ° KW.

LIST OF REFERENCE NUMBERS

1

 first cylinder, outboard cylinder, charge air receiving cylinder

2

 second cylinder, internal cylinder, deactivatable cylinder

3

 third cylinder, internal cylinder, deactivatable cylinder

3a ₁

 first inlet opening of the third cylinder

3a ₂

 second inlet opening of the third cylinder

3b

 Outlet opening of the third cylinder

4

 fourth cylinder, outboard cylinder, charge air receiving cylinder

4a ₁

 first inlet opening of the fourth cylinder

4a ₂

 second inlet opening of the fourth cylinder

4b

 Outlet opening of the fourth cylinder

5a ₁

 first suction pipe of the third cylinder

5a ₂

 second suction pipe of the third cylinder

6a ₁

 first intake pipe of the fourth cylinder

6a ₂

 second intake pipe of the fourth cylinder

7

 Intake system, intake manifold

7a

 Gesamtansaugleitung

8th

 overflow

8a

 opening

8b

 shut-off

8c

 check valve

11

 first cylinder, outboard cylinder, charge air receiving cylinder

11a ₁

 first inlet opening of the first cylinder

11a ₂

 second inlet opening of the first cylinder

12

 second cylinder, internal cylinder, deactivatable cylinder

12a ₁

 first inlet opening of the second cylinder

12a ₂

 second inlet opening of the second cylinder

13

 third cylinder, outboard cylinder, charge air receiving cylinder

13a ₁

 first inlet opening of the third cylinder

13a ₂

 second inlet opening of the third cylinder

14

 plenum

EV _3.1

 Valve lift curve of the first intake valve of the third cylinder during the partial shutdown

EV _3.2

 Valve lift curve of the second intake valve of the third cylinder during the partial shutdown

EV ₄

 Valve lift curve of the intake valves of the fourth cylinder during the partial shutdown

.delta.h

 Valve lift between an open position and a closed position

Δh _in

 Ventilhub formed in the context of the intake stroke of an intake valve of a switched off during partial shutdown intercooler cylinder

Δh _comp

 formed in the context of the compression stroke valve lift of an intake valve of a switched off during partial shutdown intercooler cylinder

OT ₃

 top dead center of the third cylinder

OT ₄

 top dead center of the fourth cylinder

.delta.t

 Opening duration of a valve

Claims (20)

Method for operating a supercharged internal combustion engine having at least one cylinder head comprising at least two cylinders ( 1 . 2 . 3 . 4 ), in which - each cylinder ( 1 . 2 . 3 . 4 ) at least one outlet opening ( 3b . 4b ) for discharging the exhaust gases via exhaust gas removal system and at least one inlet opening ( 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ ) for supplying charge air via intake system ( 7 ) and has a piston which is movable along a piston longitudinal axis between a bottom dead center UT and a top dead center OT, - at least one exhaust gas turbocharger is provided which has a turbine arranged in the exhaust gas discharge system and one in the intake system ( 7 ), at least two cylinders ( 1 . 2 . 3 . 4 ) are configured in such a way that these cylinders ( 1 . 2 . 3 . 4 ) at least two groups each having at least one cylinder ( 1 . 2 . 3 . 4 ), wherein the at least one cylinder ( 1 . 4 ) a first group, a cylinder also in partial shutdown of the internal combustion engine in operation ( 1 . 4 ) and the at least one cylinder ( 2 . 3 ) of a second group as a load-dependent switchable cylinder ( 2 . 3 ), and - each inlet opening ( 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ ) and each outlet opening ( 3b . 4b ) of a cylinder ( 1 . 2 . 3 . 4 ) is equipped with a valve drive with a valve which the associated opening ( 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ , 3b . 4b ) locks and releases, characterized in that the cylinders ( 1 . 2 . 3 . 4 ) are grouped in such a way that in each case two cylinders ( 1 . 2 . 3 . 4 ) form a cylinder pair which is a cylinder ( 1 . 4 ) of the first group and a cylinder ( 2 . 3 ) of the second group, and during the partial shutdown - the at least one outlet opening ( 3b ) of each deactivated cylinder ( 2 . 3 ) of the second group is blocked by deactivating an associated at least partially variable valve train, - at least one inlet opening ( 3a ₁ , 3a ₂ ) a deactivated cylinder ( 2 . 3 ) of at least one pair of cylinders is opened at the bottom dead center to be moved piston in the context of an intake stroke to the deactivated cylinder ( 2 . 3 ) via intake system ( 7 ) and at least one inlet opening ( 3a ₁ , 3a ₂ ) this deactivated cylinder ( 2 . 3 ) is opened in the context of a compression stroke after the piston has passed through the bottom dead center and before this piston reaches the top dead center, which when opening via the at least one inlet opening ( 3a ₁ , 3a ₂ ) from the deactivated cylinder ( 2 . 3 ) discharged charge air via overflow channel ( 8th ) to the operating cylinder ( 1 . 4 ) of the cylinder pair is supplied. Method according to claim 1, characterized in that the at least one inlet opening ( 3a ₁ , 3a ₂ ) of the deactivated cylinder ( 2 . 3 ) is opened in the context of the compression stroke later than 50 ° CA after the bottom dead center UT. Method according to claim 2, characterized in that the at least one inlet opening ( 3a ₁ , 3a ₂ ) of the deactivated cylinder ( 2 . 3 ) is opened in the context of the compression stroke later than 70 ° CA after the bottom dead center UT. Method according to claim 2 or 3, characterized in that the at least one inlet opening ( 3a ₁ , 3a ₂ ) of the deactivated cylinder ( 2 . 3 ) is opened in the context of the compression stroke later than 90 ° CA after the bottom dead center UT. Method according to one of the preceding claims, characterized in that the at least one inlet opening ( 3a ₁ , 3a ₂ ) of the deactivated cylinder ( 2 . 3 ) is closed in the context of the compression stroke before the piston reaches the top dead center OT. Method according to one of the preceding claims for operating an internal combustion engine, in which each valve has the associated opening ( 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ , 3b . 4b ) locks or releases, wherein an oscillating due to actuation valve between an open position and a closed position forms a valve lift .DELTA.h and the opening ( 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ , 3b . 4b ) Releases during opening period .DELTA.t, characterized in that the formed under the intake valve lift .DELTA.h is three times larger _in at least the as formed as part of the compression stroke valve .DELTA.h _comp, preferably _in .DELTA.h / .DELTA.h ≥ _comp. 5 Method according to one of the preceding claims for operating an internal combustion engine, in which each cylinder ( 2 . 3 ) of the second group has two inlet openings ( 3a ₁ , 3a ₂ ) for supplying charge air via intake system ( 7 ), characterized in that during partial shutdown a first inlet opening ( 3a ₁ ) a deactivated cylinder ( 2 . 3 ) of at least one pair of cylinders is opened at the bottom dead center to be moved piston in the context of an intake stroke to the deactivated cylinder ( 2 . 3 ) via intake system ( 7 ) and a second inlet opening ( 3a ₂ ) this deactivated cylinder ( 2 . 3 ) is opened in the context of a compression stroke after the piston has passed through the bottom dead center and before this piston reaches the top dead center, which when opening via the second inlet port ( 3a ₂ ) from the deactivated cylinder ( 2 . 3 ) discharged charge air via overflow channel ( 8th ) to the operating cylinder ( 1 . 4 ) of the cylinder pair is supplied. Method according to one of claims 1 to 6 for operating an internal combustion engine, in which each cylinder ( 2 . 3 ) of the second group at least two inlet openings ( 3a ₁ , 3a ₂ ) for supplying charge air via intake system ( 7 ), characterized in that during partial shutdown all the inlet openings ( 3a ₁ , 3a ₂ ) a deactivated cylinder ( 2 . 3 ) of at least one pair of cylinders are opened at the bottom dead center to be moved piston in the context of an intake stroke to the deactivated cylinder ( 2 . 3 ) via intake system ( 7 ) and to provide an intake port ( 3a ₁ , 3a ₂ ) this deactivated cylinder ( 2 . 3 ) is opened in the context of a compression stroke, after the piston has passed through the bottom dead center and before this piston reaches the top dead center, which when opening via the inlet port ( 3a ₁ , 3a ₂ ) from the deactivated cylinder ( 2 . 3 ) discharged charge air via overflow channel ( 8th ) in operation located cylinder ( 1 . 4 ) of the cylinder pair is supplied. Method according to one of claims 1 to 6 for operating an internal combustion engine, in which each cylinder ( 2 . 3 ) of the second group at least two inlet openings ( 3a ₁ , 3a ₂ ) for supplying charge air via intake system ( 7 ), characterized in that during partial shutdown all the inlet openings ( 3a ₁ , 3a ₂ ) a deactivated cylinder ( 2 . 3 ) of at least one pair of cylinders are opened at the bottom dead center to be moved piston in the context of an intake stroke to the deactivated cylinder ( 2 . 3 ) via intake system ( 7 ), and all inlet openings ( 3a ₁ , 3a ₂ ) this deactivated cylinder ( 2 . 3 ) are opened in the context of a compression stroke, after the piston has passed through the bottom dead center and before this piston reaches the top dead center, which when opening via the inlet openings ( 3a ₁ , 3a ₂ ) from the deactivated cylinder ( 2 . 3 ) discharged charge air via overflow channel ( 8th ) to the operating cylinder ( 1 . 4 ) of the cylinder pair is supplied. Method according to one of the preceding claims, characterized in that the overflow channel ( 8th ) at least from the intake system ( 7 ) is formed, wherein the overflow channel ( 8th ) the at least one opened in the context of the compression stroke inlet opening ( 3a ₁ , 3a ₂ ) of the deactivated cylinder ( 2 . 3 ) with the cylinder in operation ( 1 . 4 ) of the cylinder pair connects and at least during the compression stroke from the remaining intake system ( 7 ) is detachable channel. Method according to one of the preceding claims, characterized in that at least one inlet opening ( 4a ₁ , 4a ₂ ) of the cylinder in operation ( 1 . 4 ) of the at least one pair of cylinders is opened in order to switch off the deactivated cylinder ( 2 . 3 ) discharged charge air in the operating cylinder ( 1 . 4 ). Method according to one of the preceding claims, characterized in that at least one inlet opening ( 4a ₁ , 4a ₂ ) of the cylinder in operation ( 1 . 4 ) of the at least one pair of cylinders is opened in the context of an intake stroke to the piston to be moved to the bottom dead center, in order to remove from the deactivated cylinder ( 2 . 3 ) discharged charge air in the operating cylinder ( 1 . 4 ). Method according to one of the preceding claims for operating an internal combustion engine, in which each cylinder ( 1 . 4 ) of the first group has at least two inlet openings ( 4a ₁ , 4a ₂ ) for supplying charge air via intake system ( 7 ), characterized in that during partial shutdown an inlet opening ( 4a ₁ , 4a ₂ ) of the cylinder in operation ( 1 . 4 ) of the at least one pair of cylinders via overflow channel ( 8th ) with the deactivated cylinder ( 2 . 3 ) is connected to the deactivated cylinder ( 2 . 3 ) discharged charge air in the operating cylinder ( 1 . 4 ). A method according to claim 13, characterized in that the at least one other inlet opening ( 4a ₁ , 4a ₂ ) of the cylinder in operation ( 1 . 4 ) of the at least one pair of cylinders which are not via the overflow channel ( 8th ) with the deactivated cylinder ( 2 . 3 ) is closed before the cylinder is switched off ( 2 . 3 ) discharged charge air in the operating cylinder ( 1 . 4 ) is introduced. Method according to one of claims 1 to 12 for operating an internal combustion engine, in which each cylinder ( 1 . 4 ) of the first group has at least two inlet openings ( 4a ₁ , 4a ₂ ) for supplying charge air via intake system ( 7 ), characterized in that during partial shutdown all the inlet openings ( 4a ₁ , 4a ₂ ) an operating cylinder ( 1 . 4 ) of the cylinder pair via overflow channel ( 8th ) with the deactivated cylinder ( 2 . 3 ) are connected to the deactivated cylinder ( 2 . 3 ) discharged charge air in the operating cylinder ( 1 . 4 ). Supercharged internal combustion engine for carrying out a method according to one of the preceding claims, with at least one cylinder head comprising at least two cylinders ( 1 . 2 . 3 . 4 ), in which - each cylinder ( 1 . 2 . 3 . 4 ) at least one outlet opening ( 3b . 4b ) for discharging the exhaust gases via exhaust gas removal system and at least one inlet opening ( 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ ) for supplying charge air via intake system ( 7 ) and has a piston which is movable along a piston longitudinal axis between a bottom dead center UT and a top dead center OT, - at least one exhaust gas turbocharger is provided which has a turbine arranged in the exhaust gas discharge system and one in the intake system ( 7 ), at least two cylinders ( 1 . 2 . 3 . 4 ) are configured in such a way that these cylinders ( 1 . 2 . 3 . 4 ) at least two groups each having at least one cylinder ( 1 . 2 . 3 . 4 ), wherein the at least one cylinder ( 1 . 4 ) a first group, a cylinder also in partial shutdown of the internal combustion engine in operation ( 1 . 4 ) and the at least one cylinder ( 2 . 3 ) of a second group as a load-dependent switchable cylinder ( 2 . 3 ), and - each inlet opening ( 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ ) and each outlet opening ( 3b . 4b ) of a cylinder ( 1 . 2 . 3 . 4 ) is equipped with a valve drive with a valve which the associated opening ( 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ , 3b . 4b ) is blocked and released, wherein the at least one outlet opening ( 3b ) of each deactivatable cylinder ( 2 . 3 ) of the second group is equipped with a switch-off valve drive, characterized in that - the cylinders ( 1 . 2 . 3 . 4 ) are grouped in such a way that in each case two cylinders ( 1 . 2 . 3 . 4 ) form a cylinder pair which is a cylinder ( 1 . 4 ) of the first group and a cylinder ( 2 . 3 ) of the second group, wherein the cylinder ( 2 . 3 ) of the second group as a charge-delivering cylinder ( 2 . 3 ) the cylinder ( 1 . 4 ) of the first group as a charge air receiving cylinder ( 1 . 4 ) during the partial shutdown provides additional charge air, including an at least temporarily formable overflow channel ( 8th ) is provided, the at least one inlet opening ( 4a ₁ , 4a ₂ ) of the charge-air-receiving cylinder ( 1 . 4 ) with at least one inlet opening ( 3a ₁ , 3a ₂ ) of the intercooler cylinder ( 2 . 3 ) to charge air via the overflow channel ( 8th ) from the switched-off charge-supplying cylinder ( 2 . 3 ) in the charge air receiving in-service cylinder ( 1 . 4 ) of the cylinder pair. Supercharged internal combustion engine according to claim 16, characterized in that the intake system ( 7 ) the overflow channel ( 8th ) at least forms, wherein the overflow channel ( 8th ) than from the intake system ( 7 ) detachable channel is formed, which also by pressing a shut-off ( 8b ) via at least one opening ( 8a ) with the intake system ( 7 ) is connectable. Supercharged internal combustion engine according to claim 16 or 17, characterized in that the two cylinders ( 1 . 2 . 3 . 4 ) of a cylinder pair in each case adjacent in the at least one cylinder head arranged cylinder ( 1 . 2 . 3 . 4 ) are. Supercharged internal combustion engine according to one of claims 16 to 18, having at least one cylinder head and four cylinders arranged in series along the longitudinal axis of the cylinder head ( 1 . 2 . 3 . 4 ), the two outer cylinders ( 1 . 4 ) also in partial shutdown of the internal combustion engine in operation cylinder ( 1 . 4 ) of the first group and the two inner cylinders ( 2 . 3 ) load-dependent switchable cylinders ( 2 . 3 ) of the second group, characterized in that in each case an external cylinder ( 1 . 4 ) and the adjacent inner cylinder ( 2 . 3 ) form a cylinder pair. A supercharged internal combustion engine according to claim 19, wherein each cylinder ( 1 . 2 . 3 . 4 ) two inlet openings ( 3a ₁ , 3a ₂ , 4a ₁ , 4a ₂ ) for supplying charge air via intake system ( 7 ), characterized in that in each case the inlet opening ( 3a ₁ , 3a ₂ ) a deactivatable cylinder ( 2 . 3 ) of a cylinder pair which is the cylinder which is also in operation during partial shutdown of the internal combustion engine ( 1 . 4 ) facing this pair of cylinders, via overflow channel ( 8th ) with the inlet opening ( 4a ₁ , 4a ₂ ) of the cylinder also in partial shutdown of the internal combustion engine in operation ( 1 . 4 ) of the cylinder pair, the deactivatable cylinder ( 2 . 3 ) facing the cylinder pair, is connectable.

Images