EP1913244A1

EP1913244A1 - Method and device for operating an internal combustion engine with cylinder shutdown

Info

Publication number: EP1913244A1
Application number: EP06764232A
Authority: EP
Inventors: Dirk Hartmann; Werner Mezger; Andreas Roth; Juergen Rappold; Georg Mallebrein; Nikolas Poertner; Henri Barbier; Ingo Fecht
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2005-08-03
Filing date: 2006-07-20
Publication date: 2008-04-23
Also published as: KR20080034138A; WO2007014860A1; JP2009503355A; DE102005036440A1; US20100198482A1

Abstract

A method and a device for operating an internal combustion engine (1), in particular, in a non-firing condition, are disclosed which permit an essentially smooth switch between two operating conditions for the internal combustion engine (1) with differing numbers of operating cylinders (11, 12, ..., 18) with regard to charge exchange. Air is introduced into the internal combustion engine through a control element (5) in an air inlet (10) and the amount of air introduced into the internal combustion engine (1) controlled by the position of the control element (5). A charge exchange condition for at least one cylinder (11, 12, ..., 18) of the internal combustion engine (1) is altered. On altering the charge exchange condition of the at least one cylinder (11, 12, ..., 18) the setting of the control element (5) in the air inlet (10) is altered.

Description

METHOD AND DEVICE FOR OPERATING AN INTERNAL COMBUSTION ENGINE WITH -_ Q CYLINDER SHUT-OFF

State of the art

The invention is based on a method and a device for operating a combustion engine, in particular in an unfired state, according to the preamble of the independent claims.

It is already known to supply air to the internal combustion engine via an actuator designed, for example, as a throttle valve in an air supply, wherein the amount of air supplied to the internal combustion engine is influenced by the position of the throttle valve.

It is also known, during the unfired state of the internal combustion engine, which is achieved for example by fuel cut, to change the charge state of at least one cylinder of the internal combustion engine, for example, by permanently closing its inlet and exhaust valves, so that over this

25 sen cylinder no charge change takes place. Preferably, the charge cycle is suspended in half of the cylinders.

Advantages of the invention

The method according to the invention and the device according to the invention for operating an internal combustion engine, in particular in an unfired state, having the features of the independent claims, have the advantage that the position of the actuator in the air supply is changed as the change of charge state of the at least one cylinder changes. In this way, with a suitable change in the position of the actuator, it is possible to change the state of charge change the at least one cylinder with reduced pressure and thus perform more comfortable. A change in the state of charge change of at least one cylinder of the internal combustion engine is thus less noticed in the case of the drive of a vehicle by the internal combustion engine by the driver of the vehicle.

The measures listed in the dependent claims advantageous refinements and improvements of the main claim method are possible.

The described change in the charge cycle state of at least one cylinder of the internal combustion engine can be easily made more comfortable in the case of suspension of a previously activated charge exchange via the at least one cylinder, if the position of the actuator in the air supply in the sense of reducing the amount of air supplied to the engine is changed ,

The change in the charge cycle state of at least one cylinder of the internal combustion engine can be made particularly comfortable in the case of activation of a previously exposed charge exchange via the at least one cylinder by the position of the actuator in the air supply in the sense of increasing the internal combustion engine supplied amount of air is changed.

A defined improvement in comfort results when the position of the actuator in the air supply is changed by a predetermined value.

A maximum of comfort and a minimum of jolt with change of the charge alternation state of at least one cylinder of the internal combustion engine results when the predetermined value is determined such that after the change of the charge exchange state of the at least one cylinder and the simultaneous change of the position of the actuator, the clutch torque remains constant.

The predefined value can be determined simply by application or modeling.

It is also advantageous if the charge cycle is changed in half of the cylinders, in particular in every second cylinder of the firing order. That way A change in the charge cycle state can be implemented particularly simply by switching off or suspending the charge cycle, for example, for a complete cylinder bank of the internal combustion engine, in the event that the internal combustion engine has two such cylinder banks. In general, in the case of an even number of cylinder banks, half of the cylinder banks can be switched off completely with respect to the change of charge of their cylinders.

By changing or suspending the charge cycle every second cylinder of the firing order also a smooth engine operation is ensured.

The charge change over the at least one cylinder can be particularly easily exposed by deactivating the valve gear on the intake and / or exhaust side or activated by activating the valve train on the inlet and / or outlet side.

drawing

An embodiment of the invention is illustrated in the drawing and explained in more detail in the following description. Show it:

1 shows a block diagram of an internal combustion engine with two cylinder banks, FIG. 2 shows a functional diagram for changing the state of charge change of at least one cylinder of the internal combustion engine as a function of a request,

3 shows a functional diagram for explaining the method according to the invention and the device according to the invention for changing the position of an actuator in an air supply of the internal combustion engine as a function of the change in the state of charge of the at least one cylinder and

FIGS. 4a) to 4i) show the time profile of various operating variables of the internal combustion engine before and after a change in the state of charge change of at least one cylinder of the internal combustion engine. - A -

Description of the embodiment

In FIG. 1, 1 denotes an internal combustion engine which, for example, drives a vehicle. The internal combustion engine 1 can be designed, for example, as a gasoline engine or as a diesel engine. The internal combustion engine 1 comprises an even number in this example

Number n of cylinder banks, wherein in the example of Figure 1 n is equal to 2. Alternatively, however, the invention can also be implemented with an odd number of cylinder banks, for example, only with a single one. Each cylinder bank in the present example comprises the same number of cylinders. Thus, according to the example of FIG. 1, the internal combustion engine 1 comprises a first cylinder bank 55 having a first cylinder 11, a second cylinder 12, a third cylinder 13 and a fourth cylinder 14. Furthermore, the internal combustion engine 1 according to FIG. 1 comprises a second cylinder bank 60 with a fifth cylinder 15, a sixth cylinder 16, a seventh cylinder 17 and an eighth cylinder 18. The cylinders 11, ..., 18 of the two cylinder banks 55, 60 are supplied with fresh air via an air supply 10. In the air supply 10 is a

Actuator 5 for influencing the cylinders 11, ..., 18 arranged amount of air arranged. This amount of air varies depending on the position or position or the opening angle or opening degree of the actuator 5. In the following it is assumed by way of example that the actuator 5 is designed as a throttle valve. The flow direction of the air in the air supply 10 is indicated by arrows in FIG. The position of the throttle flap or the opening angle is determined by a controller 25 in the art, for example, depending on the operation of an accelerator pedal, not shown in Figure 1 or depending on the requirement of another vehicle system, not shown in Figure 1, such as an anti-lock braking system. a traction control, a vehicle dynamics control, a cruise control or the like driven. Downstream of the throttle valve 5 fuel is injected into the air supply 10 via an injection valve 50, wherein the control of the injection valve 50 and thus the fuel metering is also set by the controller 25 in the conventional manner, for example, to set a predetermined air / fuel mixture ratio. Alternatively, the fuel injection can also be carried out upstream of the throttle valve 5 in the air supply 10 or directly into the combustion chambers of the cylinders 11, ..., 18. Furthermore, it is provided according to Figure 1, the valve train of the cylinder 11, ..., 18 and thus their intake and exhaust valves on the part of the engine control 25 in the expert known manner by means of a fully variable valve control to control. Alternatively, this valve train can also be using Camshafts are set in the manner known in the art. The exhaust gas formed during the combustion of the air / fuel mixture in the combustion chambers of the cylinders 11,..., 18 is expelled via the exhaust valves of the cylinders 11,..., 18 into an exhaust line 65. The flow direction of the exhaust gas in the exhaust line 65 is also marked in FIG. 1 by arrows. In the exhaust system 65, an optional one

Exhaust aftertreatment device 45 arranged, for example in the form of a catalyst in order to avoid the emission of undesirable pollutants by conversion as possible.

2 shows a functional diagram is shown and designated by the reference numeral 70, with the aid of which the charge exchange state of at least one of the cylinders 11, 12, ..., 18 of the internal combustion engine is changed in response to a received request. The functional diagram 70 can be implemented in the engine control 25, for example software and / or hardware. The functional diagram 70 includes a receiving unit 40 for receiving a request from a request generating unit 80 located outside of the functional chart 70. Such a request may be, for example, a request for changing the temperature gradient of the exhaust gas after-treatment apparatus 45. Such a request can be generated by the engine controller 25. For this purpose, the engine controller 25 compares, for example, an actual temperature of the catalytic converter 45 with a setpoint temperature of the catalytic converter 45 and derives from this deviation a request for changing the temporal temperature gradient of the catalytic converter 45. Thus, for example, if the target temperature of the catalytic converter falls below a predetermined value by the actual temperature of the catalytic converter, an increase in the temperature gradient can be requested by the engine control unit 25. Conversely, when the setpoint temperature of the catalyst is exceeded by more than a predetermined value by the actual temperature of the catalyst, the engine controller 25 may request a reduction in the temperature gradient of the catalyst 45. The requirement for the change of the temperature gradient is predetermined by the request generating unit 80, which may also be implemented in the motor controller 25 software and / or hardware. Another example of a request is a deceleration request for decelerating the vehicle driven by the internal combustion engine 1. Such a deceleration request is received by the controller 25, for example, due to an actuation of a brake pedal by the driver or as a deceleration request of a vehicle system, such as an antilock brake system, for example. a traction control, a vehicle dynamics control, etc. In this case, the request generating unit 80 represents the corresponding vehicle system or the brake pedal module.

The receiving unit 40 receives from the request generating unit 80 the described request and forwards it to a converting unit 85 in the functional diagram. The conversion unit 85 converts the received request into a request for the change of charge state of the cylinders 11, 12,..., 18 and forwards this request to means 30 for changing the state of charge of the cylinders 11, 12,..., 18. The means 30 comprise an actuator which adjust the valve train of the intake and / or exhaust valves of each cylinder 11, 12,..., 18 according to the request supplied by the transfer unit 85. In this case, the inlet and / or outlet valves of each cylinder 11, 12, ..., 18 individually adjusted by the means 30, d. H. be opened or closed. Each cylinder 11,..., 18 comprises one or more inlet valves and one or more outlet valves. By the means 30 can all

Inlet valves and / or all exhaust valves of each cylinder 11, 12, ..., 18 are permanently closed, so that the charge exchange is suspended or deactivated via the corresponding cylinder for this duration. Since each cylinder 11,..., 18 can be controlled individually in the manner described, FIG. 2 shows eight outputs of the means 30. A change in the state of charge change of at least one of the cylinders 11,..., 18 thus results in that the charge exchange is suspended via the at least one cylinder 11, ..., 18 from an activated state by permanently closing all of its intake valves and / or all of its exhaust valves. Conversely, the charge exchange state of the at least one cylinder 11,..., 18 can be changed by reactivating the charge exchange via the at least one cylinder 11,..., 18, starting from the suspended state, by changing the intake and / or or exhaust valves of the at least one cylinder 11, ..., 18 are alternately opened and closed alternately depending on the cylinder cycle to carry out the charge exchange in a conventional manner.

In an advantageous embodiment, two operating states of the internal combustion engine 1 are distinguished with regard to the charge-changing state of the cylinders 11,. In a first operating state, the charge cycle is suspended over half of the cylinders 11,..., 18 by permanently closing their intake and / or exhaust valves. In this case, either the charge cycle across all cylinders one of the two Cylinder banks 55, 60a are exposed, whereas the charge cycle over all cylinders of the other two cylinder banks 55, 60 is activated. Alternatively, half of the cylinders of the first cylinder bank 55 and half of the cylinders of the second cylinder bank 60, or generally half of the cylinders, independently of which they are on the soft cylinder bank, may be deactivated with respect to the gas exchange, whereas the gas exchange over the remaining cylinders is activated , Generally and even in the case of an odd number of cylinder banks, it is only important that one part, for example half, of all cylinders of the internal combustion engine 1 is deactivated with respect to the charge exchange and the other part of all cylinders of the internal combustion engine 1 is activated with respect to the charge exchange , For example, if the firing order of the cylinders 11, ..., 18 is as follows:

First cylinder 11, fifth cylinder 16, second cylinder 12, sixth cylinder 16, third cylinder 13, seventh cylinder 17, fourth cylinder 14, eighth cylinder 18.

It can also be provided to exclude every second cylinder of the firing order from the charge cycle, regardless of the cylinder bank he is located, and to activate the charge change over the remaining cylinders. In the example described, for example, in the event that all the cylinders 11, 12, 13, 14 of the first cylinder bank 55 are excluded from the charge cycle and the charge cycle across all the cylinders 15, 16, 17, 18 of the second cylinder bank 60 is activated, exactly that every second cylinder is excluded in the firing order from the charge cycle, whereas the remaining cylinders in the firing order have a charge cycle. In this way, the smoothest possible engine operation is achieved despite the charge change that is exposed in half of the cylinders.

In a second operating state, all cylinders 11,..., 18 are to be activated with regard to the charge exchange.

The change in the charge-changing state of the cylinders 11,..., 18 now takes place simply by switching between the first operating state and the second operating state. The first operating state is also referred to as a half-engine operation and the second operating state as a full engine operation. This switching between the two operating states can take place both in the fired and in the non-fired operation of the internal combustion engine 1. In the unfired operation is the Fuel injection via the injection valve 50 permanently hidden in contrast to the fired operation, during which fuel is injected regularly. The fired operation of the internal combustion engine 1, for example, characterizes a train operation and the unfired operation, for example, in a coasting operation of the internal combustion engine 1 before. The unfired overrun operation of the internal combustion engine 1 is also called

Overrun cutoff, d. H. the affected injection valves of all cylinders are closed.

In the following, it is to be assumed by way of example that the switchover between the first operating state and the second operating state takes place in the uncontrolled operation of the internal combustion engine 1, that is, for example, during overrun fuel cutoff.

It is now provided to change the position of the throttle valve 5 with the change of the charge change state of the at least one cylinder 11,... 18, wherein as described in this embodiment, the change of the charge exchange state of the at least one cylinder 11, ..., 18 is represented by the switching between the first operating state and the second operating state. This measure has the purpose of avoiding as far as possible jerking the internal combustion engine 1 or the vehicle driven by it when switching between the first operating state and the second operating state and thus making the operation of the internal combustion engine more comfortable. For this purpose, it is provided, with the suspension of a previously activated charge exchange via at least one cylinder 11, ..., 18 to change the position of the throttle valve 5 in the sense of reducing the amount of air supplied to the internal combustion engine 1. This means that when switching from the second operating state to the first operating state, the throttle valve is actuated in the closing direction.

Accordingly, upon activation of a previously exposed charge change via at least one cylinder 11,..., 18, the position of the throttle valve 5 is changed in the sense of an increase in the amount of air supplied to the internal combustion engine 1. This means that when switching from the first operating state to the second operating state, the throttle valve 5 is actuated in the opening direction.

It has proven to be advantageous to change the position of the throttle valve 5 by a predetermined value. In this case, the predetermined value is determined such that after the change in the state of charge change of the at least one cylinder 11, 12,..., 18 and the changing of the position of the throttle valve 5 at the same time to change the state of charge change, the clutch torque of the internal combustion engine 1 compared to the change of the charge change state of the at least one cylinder 11, ..., 18 remains constant. In this way, namely the

Ruck the internal combustion engine 1 and the vehicle in the change of the charge cycle state of at least one cylinder 11, ..., 18 ideally completely avoided. The predetermined value for changing the position of the throttle valve 5 can be determined by application, for example, on a test bench depending on the current operating state of the internal combustion engine 1, in particular depending on the engine speed and the engine load of the internal combustion engine 1. The predetermined value can alternatively be determined by modeling. An example of such a modeling of the predetermined value for the change in the position of the throttle valve 5 is explained with reference to the functional diagram 75 in FIG.

At the output of the internal combustion engine 1, a loss torque is formed due to the engine friction and the charge cycle losses. The loss torque therefore corresponds to the sum of the friction torque and the charge cycle torque loss. In a first torque determination unit 90 of the second function diagram 75, the current charge cycle torque loss value is determined in a manner known to those skilled in the art. in the

The target must correspond to the current charge cycle torque loss value in the first operating state to that in the second operating state. Since the charge cycle loss torque in the first operating state is only half as high as in the second operating state, the current charge cycle torque loss value in a multiplier element 95 must be multiplied by a factor of two. From the product formed in this way, in a subtraction element 105 of the function diagram 75, the charge cycle loss torque value is subtracted, which results for the cylinders in which the charge change is suspended. This value is determined in a second torque detection unit 92 and is zero in the first operating state of the internal combustion engine 1, because in the cylinders in which the charge change is exposed, no

Charge change losses and thus no charge cycle loss torque can occur. The difference at the output of the subtraction element 105 thus corresponds to the charge cycle torque loss value of those cylinders whose charge change is activated. This charge cycle torque value of the cylinders with activated A change of mode, for example, is due to an inverse integral function * dV of the pV-

Diagram of the internal combustion engine 1 supplied as an input variable, wherein p _{s of} the intake manifold pressure downstream of the throttle valve 5 and p _{u is} the ambient pressure. At the output of the inverse integral function, the intake pipe pressure p _{s associated} with the charge cycle torque loss value of the cylinder with activated charge change is then obtained. The ambient pressure p _u can be determined, for example, by means of a pressure sensor, not shown in FIG. 1, in a manner known to those skilled in the art. Instead of the inverse integral function, it is also possible to use a characteristic diagram or a characteristic curve which has been applied for example on a test stand. The inverse integral function is identified by the reference numeral 110 in FIG. The intake manifold pressure p _s at the output of the inverse integral function 110 is supplied to a characteristic curve 115, which converts the intake manifold pressure p _s into the assigned value for the cylinder charge rl. In the simplest case, instead of the characteristic curve 115, a multiplication element may be used which multiplies the intake manifold pressure p _s by a conversion factor fupsrl in order to obtain the value for the inflation rate. The conversion factor or the characteristic curve 115 can also be applied, for example, on a test bench as a function of the operating state of the internal combustion engine 1, that is to say in particular of engine speed and engine load. The charge rl determined from the characteristic curve 115 or by means of the conversion is fed to an actuation unit 35 of the function diagram 75 which determines the opening angle of the throttle valve 5 associated with the charge rl. The actuating unit 35 then causes an adjustment of the opening angle of the throttle valve 5 to the determined opening angle and thus a change in the opening angle of the throttle valve 5 by an opening angle determined by the operating unit 35 and the opening present before the switching between the first and the second operating state. given angle. In this case, the actuating unit 35 causes an actuation of the throttle valve 5 in the closing direction to the determined opening angle when a switchover from the second operating state was detected in the first operating state. However, has been switched from the first operating state to the second operating state, the actuating unit 35 causes an actuation of the throttle valve 5 in the opening direction to the determined opening angle. The detection of the actuating unit 35, whether switched from the first operating state to the second operating state or from the second operating state to the first operating state is effected by supplying a corresponding signal B hmb, which is shown in Figure 4h). This signal is set in the first operating state and reset in the second operating state and is generated and delivered by the means 30 as required to the charge cycle state of the cylinders. This signal is then supplied to the actuator 35.

By changing the position of the throttle valve 5 by the operating unit 35, a change in the clutch torque of the internal combustion engine 1 due to the switching between the first operating state and the second operating state i- dealer manner completely compensated. The charge cycle torque loss value at the output of the first torque detection unit 90 is labeled MdLW. The output of the second torque detection unit 92 as the charge loss torque value of the cylinder not activated with respect to the charge exchange with MdLWHMB, the output of the subtractor 105 as Ladungswechselverlustmomentenwert the cylinder with respect to the charge exchange activated with MdLWVMB, the output of the inverse integral function 110 as intake manifold pressure p _s , the output of the characteristic 115th as a filling with rl and the value at the output of the actuator 35 with wdk. When switching from the second operating state to the first operating state, as described, the charge cycle torque value MdLWHMB determined by the second torque determination unit 92 is equal to zero and thus MdLWVMB is equal to 2 * MdLW. When switching from the first operating state to the second operating state, the charge cycle torque loss value MdLWHMB determined by the second torque determination unit 92 is the charge cycle torque loss value of those cylinders which have previously been switched off with respect to the charge cycle and are now activated. Insofar, MdLWHMB = 0.5 * MdLW = MdLWVMB.

The mode of operation of the function diagram 75 according to FIG. 3 will now be explained with reference to the time diagrams of different operating variables of the internal combustion engine 1 according to FIGS. 4a) to 4i) using an example of switching from the second operating state to the first operating state.

According to FIG. 4i), a signal B SU is constantly set over the considered time period and thus indicates that overrun fuel cutoff has occurred. If signal B SU is reset, there is no fuel cut-off. The signal B SU is generated by the engine controller 25. Furthermore, FIG. 4h) shows the course of the signal B hmb which is generated by the means 30 as described. This signal B hmb is reset until a first time ti and is set at the time ti, in order subsequently to be in the set state remain. This means that the internal combustion engine 1 is in the second operating state until the first time ti and then in the first operating state. So at the first time ti is switched from full engine operation in the half-engine operation. According to FIG. 4 a), the degree of opening of the throttle flap 5 is the value wdkl up to the first time point ti. Without the described function of the second function diagram 75, the degree of opening of the throttle flap 5 would continue to remain constant after the first time t.sub.i, provided that there are constant boundary conditions, in particular in the form of a constant driver request or constant requests from other vehicle systems, such as For example, anti-lock system, traction control, vehicle dynamics control, cruise control or the like. Due to the deactivated after the first time ti cylinder in semi-motor operation and the lack of charge change there, the outflow in the intake manifold, which characterizes the part of the air supply downstream of the throttle valve 5, in the sense of reducing this outflow. Thus, the intake manifold pressure p _s rises asymptotically from the first time ti starting from a first value p _s i to a second value

Value p _S2 according to Figure 4c), because the degree of opening of the throttle valve 5 remains constant. The course of the intake pipe pressure p _s is therefore not sudden but steady, because the intake manifold pressure p _s downstream of the throttle valve 5 must build up only with time. The charge cycle losses are due to the pressure ratio of the intake manifold pressure p _s to the ambient pressure p _u according to the p-V diagram of the internal combustion engine 1. With increasing intake manifold pressure p _s thereby falls the charge cycle loss torque. In addition, the charge cycle losses across the intake and exhaust valves of the cylinders 11, ..., 18 become smaller, since only half of the cylinders 11,..., 18 are active with respect to the charge exchange. Until the first time ti, the total charge cycle loss moment MdLWg according to FIG. 4b) is a value MdI. This corresponds to the entire

Charge change loss torque MdLWg until the first time ti the charge cycle loss torque of both the first cylinder bank 55 and the second cylinder bank 60th The total charge cycle loss MdLWg is always the average of the charge cycle torque loss of the two cylinder banks 55, 60. At the first time ti jumps the charge cycle loss torque MdLWHMB the first time ti with regard to the change of charge deactivated cylinder bank to the value zero. Due to the increasing intake pipe pressure p _s from the first time ti on, the charge cycle loss torque MdLWVMB of the cylinder bank, whose cylinders are still activated with respect to the charge exchange even after the first time ti, falls asymptotically down to a value Md3. This results in the course of the entire charge cycle. loss torque MdLWg as the mean value between the charge cycle loss moments MdLWHMB, MdLWVMB of the two cylinder banks as shown in FIG. 4b). The entire charge cycle loss torque MdLWg therefore jumps to a value Md2 = ¹ A MdI at the first time ti and asymptotically decreases therefrom to a value Md3 / 2, in the example according to FIG. 4b) Md3 being smaller Md2. With the boost pressure p _s , the charge rl according to FIG. 4d) also rises asymptotically from a first time ti starting from a first value r11 to a second value rl2. According to FIG. 4e), the air mass flow msdk via the throttle valve 5 remains constant over the entire time considered, provided that the internal combustion engine 1 is operated in the supercritical operating range in which the air in the air supply 10 moves at the speed of sound.

The frictional torque MdR according to FIG. 4f) is also assumed to be constant over the entire time duration. The clutch torque MdK as the difference between the internal torque Mi and the total torque loss Mv of the internal combustion engine 1 jumps from a value Md6 to a value Md7> Md6 at the first time ti and increases from the value Md7 for times t> ti to a value Md4 according to the dashed line Line in Figure 4g). In this case, the loss torque Mv of the internal combustion engine 1 is equal to the sum of the friction torque MdR and the total charge cycle loss torque MdLWg. Insofar, assuming a constant internal moment Mi = O of the internal combustion engine 1, the profile of the clutch torque MdK is inverse to the course of the total charge-exchange torque MdLWg.

By means of the functional diagram 75 according to the invention according to FIG. 3, the charge cycle torque MdLWVMB is detected in the described manner, in particular beginning with the first time ti, and from this with the aid of the pV diagram the associated intake manifold pressure p _s and therefrom the associated charge rl and therefrom the required position of the throttle valve 5 for compensation of said changes in the filling rl, the intake manifold pressure p _s and the charge exchange torque MdLWVMB determined. This position of the throttle valve 5 is set at the first time ti by the actuating means 35, which manifests itself in a change from the opening degree wdkl to the opening degree wdk2 <wdkl at the first time ti in accordance with the solid curve of the opening degree wdk according to FIG. 4a). This ultimately leads to the filling rl according to the dashed curve in Figure 4d) after the first time ti in comparison to before the first time ti is constant as well as the intake manifold pressure p _s . For the course of the entire charge cycle loss torque MdLWg according to the solid line in FIG. 4b), this means that the entire charge cycle loss torque MdLWg subsequently rises asymptotically again towards the value MdI after the jump to the value Md2 = 0.5 * MdI at the first time ti , In a corresponding manner, the clutch torque MdK jumps from the value Md6 to the value Md7> Md6 at the first time ti, in order then to return asymptotically to the value Md6. In that regard, the clutch torque MdK in the process according to the invention in comparison to the dashed curve can be kept largely constant at the value Md6 up to the said jump. As a result, the driver of the motor vehicle driven by the internal combustion engine 1 does not perceive the changeover from the second operating state to the first operating state at the first time ti as little as possible (caused by said jump) or not at all.

Thus, therefore, the Saugrohr- pressure increase from the first time ti is approximately completely compensated by the inventive measure described. Consequently, the intake manifold pressure p _s remains approximately constant as described. If the intake manifold pressure p _s remains approximately constant, then the pressure ratio intake manifold pressure p _s to the ambient pressure p _{u will} remain constant. As described, this leads to the fact that the entire charge cycle loss torque MdLWg asymptotically returns to the original value MdI after the jump at time ti, as a result of which the clutch torque MdK returns asymptotically to the original value Md6 after the jump at the first time ti.

When switching over from the half-engine operation to the full-engine operation, a jerk of the internal combustion engine 1 can be largely avoided by this switching in a corresponding manner, such that analogously z. B. the degree of opening of the throttle valve 5 is appropriately increased with the switch to full engine operation to asymptotically return the entire charge cycle loss torque MdLWg and thus the clutch torque MdK after the jump caused by switching to the value immediately before the jump and thus before the switch to full engine operation was present. In a corresponding manner, the intake manifold pressure p _s and the charge rl behave approximately constant during the switchover from half engine operation to full engine operation. The suspension of the charge exchange via the at least one cylinder 11, 12, ..., 18 takes place by permanently closing its intake and / or exhaust valves or in other words by deactivating its valve drive on the intake and / or exhaust side. The activation of the charge exchange via the at least one cylinder 11, 12, ..., 18 takes place by operating the intake and / or exhaust valves of this at least one cylinder 11, 12, ..., 18 in a conventional manner and described above, with In other words, as activation of the valve train of this at least one cylinder on the inlet and / or outlet side is called.

By the inventive method and the inventive device for

Operation of the internal combustion engine 1 makes it possible, in particular in an unfired state of the internal combustion engine 1, to carry out largely smooth switching between two operating states of the internal combustion engine 1, which differ with regard to the number of cylinders that are activated with regard to the charge exchange.

Claims

claims

1. A method for operating an internal combustion engine (1), in particular in a non-fired state, wherein the internal combustion engine (1) via an actuator (5) in an air supply (10) air is supplied and the internal combustion engine (1) supplied amount of air the position of the actuator (5) is influenced and wherein a charge-exchange state of at least one cylinder (11, 12, ..., 18) of the internal combustion engine (1) is changed, characterized in that with a change in the charge-transfer state of the at least one cylinder (11, 12, ..., 18) the position of the actuator (5) in the air supply (10) is changed.

2. The method according to claim 1, characterized in that with exposure of a previously activated charge exchange via at least one cylinder (11, 12, ..., 18), the position of the actuator (5) in the air supply (10) in the sense of reducing the the internal combustion engine (1) supplied amount of air is changed.

3. The method according to any one of the preceding claims, characterized in that with activation of a previously exposed charge exchange via at least one cylinder (11, 12, ..., 18), the position of the actuator (5) in the air supply (10) in the sense of Increase of the internal combustion engine (1) supplied amount of air is changed.

4. The method according to any one of the preceding claims, characterized in that the position of the actuator (5) in the air supply (10) is changed by a predetermined value.

5. The method according to claim 4, characterized in that the predetermined value is determined such that after the change of the gas exchange state of the at least one cylinder (11, 12, ..., 18) and simultaneously taking place to change the position of the actuator ( 5) the clutch torque remains constant.

6. The method according to claim 4 or 5, characterized in that the predetermined value is determined by application or modeling.

7. The method according to any one of the preceding claims, characterized in that the charge change in the case of half of the cylinders (11, 12, ..., 18), in particular every second

Cylinder (11, 12, ..., 18) of the firing order, is changed.

8. The method according to any one of the preceding claims, characterized in that the charge exchange via the at least one cylinder (11, 12, ..., 18) by deactivating its valvetrain on the inlet and / or outlet side exposed or by activating the valve train is activated on the inlet and / or outlet side.

9. Device (25) for operating an internal combustion engine (1), in particular in an un-fired state, wherein the internal combustion engine (1) an actuator (5) in an air supply (10) of the internal combustion engine (1) for influencing the internal combustion engine ( 1), with means (30) which change a state of charge change of at least one cylinder (11, 12, ..., 18) of the internal combustion engine (1), characterized in that actuation means (35) are provided which change the change of charge state of the at least one cylinder (11, 12, ..., 18), the position of the Stellglie- change (5) in the air supply (10).