WO2009152932A1

WO2009152932A1 - Method for operating a vehicle drive train with an internal combustion engine having several cylinders which can be shut off selectively, and vehicle drive train

Info

Publication number: WO2009152932A1
Application number: PCT/EP2009/003740
Authority: WO
Inventors: Peter Kreuter
Original assignee: Meta Motoren- Und Energie- Technik Gmbh
Priority date: 2008-05-27
Filing date: 2009-05-26
Publication date: 2009-12-23
Also published as: DE102008025376A1

Abstract

The invention relates to a method for operating an internal combustion engine having several cylinders, in which pistons connected to a common crankshaft (102) are operating. According to the invention, load adjustment is at least partly achieved in that the cylinders are selectively fired according to a predefined programme. Changes in angular speed of the crankshaft, which may result from the selective firing of the cylinders, are reduced by coupling a movable balancing mass component (14) to the crankshaft in such a manner that the kinetic energy of the balancing mass component increases in phases, in which the angular speed of the crankshaft would increase without being coupled to the balancing mass component, and decreases in phases in which the angular speed of the crankshaft would decrease without being coupled to the balancing mass component. Furthermore, an electric machine (122) is provided which compensates remaining fluctuations in rotational speed following the balancing of the rotational non-uniformities of the crankshaft by means of the balancing mass component.

Description

A method of operating a vehicle powertrain with an internal combustion engine having a plurality of selectively deactivatable cylinders and vehicle driveline

The invention relates to a method for operating a vehicle drive train with an internal combustion engine having a plurality of cylinders, in which work with a common crankshaft connected pistons, in which method the load adjustment of the internal combustion engine takes place at least partially, that the cylinders are selectively switched off according to a predetermined program. The invention further relates to a vehicle drive train.

FIG. 8 shows, with the dashed line, a driving cycle as measured in the NEDC (New European Driving Cycle) for consumption measurement. The abscissa shows the test time in seconds; the right-hand ordinate shows the driving speed.

If such a drive cycle is traversed by a vehicle of the "Golf Class" with a conventional four-cylinder gasoline engine with two liters of displacement, the internal combustion engine is operated under normal transmission ratios constantly in partial load operation, ie in an operating range in which the filling of the individual cylinders far below the As is well known, the specific consumption of the internal combustion engine rises, starting from a minimum, with decreasing load, which increase is more pronounced in gasoline engines than in diesel engines.

In Fig. 8, on the left-hand ordinate, the fired cylinders and operating states of the internal combustion engine are indicated, in which cylinders are selectively turned off. 2 ZyI-P means an operation in which, compared to the normal four-cylinder operation exposes a cylinder, the subsequent cylinder is fired, then again exposes a cylinder, which is then fired subsequent cylinders and then expose all four cylinders, after which the cycle restarts ( Two-cylinder operation with break). 2 ZyI means that the internal combustion engine is operated such that a cylinder exposes between each two fired cylinders. 4 ZyI means that all four cylinders are fired in the usual way. As can be seen, by far the largest part of the NEDC is sufficient to operate the Internal combustion engine in 2 ZyI-P mode. For a small part of the 2 ZyI mode is required. For an even smaller part, all four cylinders are needed.

FIG. 9 indicates the fuel consumption savings possible in the NEDC through cylinder deactivation, depending on the possible operating modes. The mode 4/2 means that the machine is operated in 4 ZyI mode as well as in 2 ZyI mode. The mode 4/2/2 -P means that all modes shown in Fig. 10 are possible. The respective modes used to idle the machine are specified separately. As can be seen, depending on the mode, consumption benefits of between 10 and 18% can be achieved. This is because the engine is operated in 2 ZyI mode compared to the 4 ZyI mode with double medium pressure (double cylinder filling) and operated in 2 ZyI-P mode with an effective displacement of only 500 cm ³ and corresponding to four times the mean pressure. In Fig. 11 further possible at constant driving consumption reductions, depending on the respective mode specified.

All values given refer to an operation of the internal combustion engine in which the charge exchange valves of the non-fired cylinders remain closed to prevent flow losses and cooling. This is possible by known switchable valve trains or valve actuation device.

One problem associated with cylinder deactivation is the consequent substantial increase in rotational irregularities and rotational speed variations of the crankshaft and nonuniformities and variations in torque delivered by the crankshaft, thereby compromising ride comfort for the vehicle occupants.

Fig. 10 shows for a four-cylinder engine in 2 ZyI mode, in which after each 360 ° crankshaft rotation is a power stroke of two liters of displacement in an operation with a mean pressure of 2 bar and a mean speed of 2000 min ^"1 in the line I den The torque is indicated on the left-hand ordinate as a deviation from the mean value, where O Nm corresponds to the mean value._ The speed or angular velocity is indicated on the right-hand ordinate._ The abscissa indicates the respective position of the As can be seen, the angular velocity and the torque curve change with a peri- odizität, which corresponds to the distance between the firing of two cylinders (in the example 360 °) to the mean value of 2000 min ^"1 or the mean value of the torque.

Fig. 11 corresponds to Fig. 10, but shows the situation in 2 ZyI-P mode. As can be seen, both the torque changes and the angular velocity changes are significantly greater than in the 2 ZyI mode. Thus, the four rotations of the crankshaft remains average speed of about 2000 min ^"1 constant, the needs during the work cycles (each at 180 ° and 540 ° of crankshaft rotation) applied torque, that is, the filling of the respective cylinder, be considerably greater than in the case of 10, in contrast to FIG. 10, the angular velocity does not fluctuate within one crankshaft revolution about an average value, but first increases significantly at 180 ° CA and 540 ° CA, and then decreases again, so that averaged over two crankshaft revolutions Mean value of 2000 min ^{"1 is} reached.

As can be seen from a comparison of Figures 10 and 11, in the 2 ZyI-P mode, the time changes of the torque and the speed, which are associated with a power stroke, considerably larger than in 2 ZyI mode. The torque and speed fluctuations which are triggered directly by a power stroke are referred to below as torque or rotational non-uniformity. They are repeated at the distance of the power strokes. These nonuniformities are superimposed by a speed fluctuation which has the periodicity given by the mode, that is, in the example of FIG. 13, a periodicity of four crankshaft revolutions.

DE 10 2005 001 047 A1 discloses a vehicle drive train with a multi-cylinder internal combustion engine and an electric machine. When cylinder deactivation of the internal combustion engine, the electric machine is driven such that the recorded or delivered by her torque reduces rotational irregularities of the internal combustion engine. In order for rotational irregularities of a multi-cylinder internal combustion engine operated in the cylinder deactivation mode to be effectively reduced by means of the electric machine, high short-time powers of the electric machine and a correspondingly powerful design of the semiconductor switching elements required for controlling the electric machine and an electrical energy store tuned to the high powers are required. In DE 34 31 368 C2 an internal combustion engine is described, which has a compensating device formed by two balance shafts for generating a damping torque in Zylinderabschaltbetrieb. The two balancer shafts are rotatably coupled in the cylinder deactivation with the crankshaft of the internal combustion engine, wherein the phase position of balancing weights of the balancer shafts relative to the crankshaft is such that Dreun- ungleichigkeiten be compensated by mass balance.

In DE 10 2005 011 910 Al is a vehicle with an internal combustion engine, which is operable in Zylinderabschaltmodus. The powertrain of the vehicle further includes an electrically variable transmission with a torsion damper assembly and a Elektromaschi- ne, by means of the compression pulses of the engine can be reduced, when the damper assembly is decoupled. The damper assembly includes a plurality of damper springs having different spring constants so that the torsional damper assembly dampens nonuniform torque variations of the internal combustion engine that occur in skip-off mode.

DE 100 05 582 A1 describes a drive train for a motor vehicle which, in addition to an internal combustion engine, has a functional electric machine arranged in parallel therewith with a stator and a rotor fixed to the drive train. One or more pendulum-like absorber masses are arranged on the rotor or coupled to the rotor. With such absorber masses constituting a torsional vibration absorber, torsional vibrations can be similarly mitigated to some extent, such as with elastically coupled absorber masses integrated in the drive train.

DE 195 32 135 A1 describes a drive system for a motor vehicle having an internal combustion engine and an electric machine which can be coupled to the crankshaft of the internal combustion engine and which is designed such that it can start the internal combustion engine when stationary and enables automatic start-stop operation.

DE 199 13 015 A1 describes a vibration damper system for a drive system of a motor vehicle with an electric machine which can be controlled in such a way that rotational speed irregularities in the drive train can be reduced. A deflection mass arrangement with at least one deflection mass and at least one deflection path is fastened to a rotating component of the drive train, along which the deflection kungsmasse is movable. The deflection path has a vertex area and deflection areas extending therefrom in the circumferential direction, wherein the vertex area is a region of maximum radial distance of the deflection path from the rotational axis of the rotary component.

The invention has for its object to provide a vehicle powertrain with a Mehrzy- linderbrennkraftmaschine and an electric machine, in which by cylinder deactivation possible fuel consumption benefits are used to a high degree without this is not associated with the vehicle occupants comfort degradation. A solution to this problem is achieved with the features of claim 1.

In the method according to the invention according to claim 1 occurring angular speed changes of the crankshaft due to the cylinder deactivation are reduced by means of at least one movable balancing mass component. This balancing mass component is coupled to the crankshaft in such a way that kinetic energy is supplied to it in predetermined rotational phases of the crankshaft, in which a respective cylinder ignites, which is fed back into the crankshaft in phases in which no ignition takes place. The coupling between the crankshaft and the balancing mass component is such that such an energy exchange also takes place when the crankshaft rotates at a constant speed, so that with the help of the balancing mass component angular velocity changes the crankshaft, so to speak before their formation and thus "at the root" fought The temporal gradients of the speed fluctuations remaining in the drive train after compensating the rotational irregularities of the crankshaft are then considerably smaller than the rotational irregularities of the crankshaft before it is equalized by the balancing mass component, so that according to the invention, the electrical power required to compensate for the speed fluctuations is considerably reduced compared with the prior art ,

The dependent claims 2 and 3 indicate two advantageous alternative coupling possibilities of the electric machine to the drive train. It is achieved with the features of claim 4 that the effectiveness of the compensating mass component can be adapted to the load of the internal combustion engine and thus to the occurring rotational irregularities.

The dependent claims 5 and 6 indicate two ways in which the coupling of the balancing mass component with the crankshaft and the operation of the electric machine can be controlled.

The claim 7 indicates the basic structure of the vehicle drive train, which is operable according to the inventive method.

The vehicle drive train according to the invention is further developed with the features of claims 8 to 16 in an advantageous manner.

The invention is explained below with reference to schematic drawings, for example, and with further details.

In the figures represent:

1 shows a principle arrangement of an internal combustion engine according to the invention,

2 torque and speed curves in 2 ZyI mode with effectiveness of a balancing component,

3 torque and speed curves in 2 ZyI-P mode with effectiveness of a balancing component,

4 shows speed curves for explaining the effectiveness of a coupled via an adder electric machine,

Fig. 5 u. 6 end views of a compensation device with a movable compensation mass component,

7 is a schematic diagram of an adjusting device,

8 shows the driving profile to be traversed in the NEDC with the required operating modes,

FIG. 9 shows possible fuel savings in the NEDC due to different operating modes; FIG.

Fig. 10 speed and torque fluctuations in the mode 2 ZyI, and Fig. 1 1 speed and torque fluctuations in the mode 2 ZyI-P.

According to FIG. 1, a drive train of a vehicle has an internal combustion engine 100, in the example shown a four-cylinder internal combustion engine, whose crankshaft 102 is connected directly or via an intermediate shaft rotatably connected to the crankshaft to an input of a coupling device 104 whose output shaft 106 is connected via a coupling 108 and a transmission 110 is connected to a drive shaft 112 of the vehicle, which in turn drives the wheels of a driven vehicle axle or, in four-wheel drive, all wheels of the vehicle via a differential 114.

According to the invention, the drive train includes a compensation device which has a mechanical part 120 cooperating with the crankshaft of the internal combustion engine and an electrical part 124 containing an electric machine 122 and the coupling device 104. The electric machine can be controlled by means of a controllable inverter 126 and be switched in a conventional manner between regenerative and motor operation, where it stores electrical energy stored in regenerative operation in an electrical energy storage 128 and 128 takes energy from the energy storage in motor operation.

The clutch 108 and the transmission 110 may be of any known type, such as starting clutch, converter clutch, manual transmission, automatic transmission, etc.

The coupling device 104, with which the electric machine 122 is coupled to the crankshaft 102, can be of very different types. In the simplest case, it is formed directly by a rotatably connected to the crankshaft 102 rotor of the electric machine 122, wherein the output shaft 106 may then be integrally formed with the crankshaft 102. The rotor need not be disposed directly on the crankshaft, but may be coupled via a gear stage, with which the speed of the output shaft of the electric machine 122 is translated to the rotational speed of the crankshaft 102 and output shaft 106, respectively.

In a modified embodiment, the coupling device 104 may be formed by an adding gear, for example a planetary gear, whose sun gear 104a is non-rotatably connected to the crankshaft 102, whose planet carrier 104b is connected to the output shaft 106 is rotatably connected and whose ring gear 104c is rotatably connected to the electric machine 122.

For such a planetary gear generally applies:

n _s + (Z _H / Z _S ) xn _H - (1 + Z _H / Z _S ) xn _P = 0, where

ns = speed of the sun gear, Π _H = speed of the ring gear, np = speed of the planet carrier, Z _H = number of teeth of the ring gear, and Zs - number of teeth of the sun gear.

The electric machine 122 may be the only machine for power generation of the vehicle. In this case, the energy storage 128 is a common vehicle battery. If the electric machine 122 is present in addition to the usual electrical vehicle equipment, its associated energy storage 128 may be formed only by a capacitor.

To control the described arrangement, an electronic control unit 132 is provided, whose inputs with an accelerator pedal sensor 134 and other sensors, such as a speed sensor 136 for detecting the vehicle speed, a speed sensor for detecting the rotational speed of the machine 100, a sensor for detecting the temperature of the machine, etc . are connected. The controller 132 includes a microprocessor with program and data memories in a manner known per se and is functionally divided into a selective control device 132a, a load control device 132b, a compensation control device 132c and an electric machine control device 132d. The selective control device 132a determines the mode in which the engine 100 is operated, depending on the operating conditions of the powertrain, such as the position of the accelerator pedal and the vehicle speed. The load control device 132b controls the load actuator 138 and other parameters of the internal combustion engine. The compensation control device 132 c controls the adjusting device 140 and the electric machine control device 132 d controls the electronic control device 126 of the electric machine 122. An embodiment of the balancing device will be described below. In the following, the basic function of the compensation device will first be explained.

Fig. 2 corresponds to Fig. 12, but with active mechanical part 120 of the balancer. The registered designation "with CRE" means with effective "Crankshaft Rotation Equalizer". As can be seen, in comparison with FIG. 22, both the torque changes and the angular velocity changes are considerably reduced.

Fig. 3 corresponds to Fig. 13, but with effective mechanical part 120 of the balancer. As can be seen, the torque nonuniformity with respect to FIG. 13, in particular in the range from 0 ° CA to 720 ° CA, is also clearly reduced here. Accordingly, the angular velocity changes compared to the Fig. 13 are significantly improved. Clearly visible is the fluctuation of the rotational speed about the mean rotational speed of 2000 min ^-1 associated with the periodicity of the firing of the internal combustion engine, ie four crankshaft revolutions, which is not compensated by the mechanical part 120 of the compensating device.

According to the invention, the electric machine is used essentially only for compensating the angular velocity changes which remain after mechanical compensation of the rotational non-uniformities. As can be seen from the figures, the electric machine then serves essentially only to compensate for the speed increase and the speed drop of the crankshaft of the internal combustion engine, which is more pronounced, the greater the crank angle distance between two fired cylinders. In this way, the power requirement of the electric machine can be significantly reduced and only a relatively small energy storage is required for temporary storage of the electrical energy generated by the electric machine in generator operation, for example, a capacitor.

FIG. 4 shows, by way of example, the effectiveness of the electric machine 122 (FIG. 1) in its coupling via the adder gear 104 for compensating the speed fluctuations according to the curve II of FIG. 3. The curve ns of FIG. 4 shows, with reference to the left Ordinate, the speed ns of the sun gear 104a of the planetary gear, which is equal to the rotational speed of the crankshaft 102. When stationary ring gear 104c, the speed of the planet carrier 104b, which is equal to the speed of the output shaft 106, np = n _s / (l + Z _H / Z).

If Z _H / Z _S = 0.5, at a crank speed of 2000 min ^"1, the speed of the output shaft 106 is about 1330 min ^{" 1} .

The curve nπ indicates the rotational speed of the ring gear, relative to the right ordinate, with which the deviation of the rotational speed of the sun gear from the target rotational speed 2000 min ^'1 can be compensated, so that the rotational speed of the planet carrier np at the value of about 1300 min ¹ , when the electric machine 122 does not require compensation for speed variations, the ring gear 104c is locked by means of a brake (not shown) controlled by the electronic control device 132, which can also engage the electric machine 122 Speed fluctuation about a target value, in the example shown, a compensation of the variation of the speed of the sun gear to 2000 min ^{"1 is} required, the rotational speed of the electric machine 122 is controlled such that the rotational speed of the planet carrier or the output shaft 106 on from the translation of the Adding gear resulting constant value remains. The ratio of the electric machine 122 to the ring gear 104c is selected in each case with regard to a favorable design of the electric machine which, when the brake is released, must apply the support torque for supporting the torque introduced via the crankshaft 102. Even if the speed control of the electric machine 122, which is operated at negative speeds nu of FIG. 4 as a generator and motor at positive speeds, does not allow complete compensation of the speed deviations, so you can still compensate for the speed fluctuations to a considerable extent.

In the following, the mechanical part 20 of the compensation device will be described by way of example:

Referring to Figure 5, which shows an end view of the mechanical part 120 (Figure 1) of the balancer, the crankshaft 102 of the reciprocating internal combustion engine has a radially projecting cam lobe 12 rotatably connected to or integrally formed with the crankshaft 102. On the crankshaft 102, a compensation mass component 14 is mounted next to the driving lug 12, which is balanced with respect to the axis of rotation A of the crankshaft 10 in an advantageous manner. Axially next to the balancing mass component 14 is a bearing plate 16 (hatched, in Fig. 5, the axial arrangement is not visible) pivotally mounted about an axis A of the crankshaft 102 remote from the axis B to a motor housing, not shown. The bearing plate 16 has a passage opening 20 through which the crankshaft 10 extends, so that the described assembly can be arranged at a front end of the crankshaft or in a central region of the crankshaft. The pivot axis B is parallel to the axis of rotation A of the crankshaft. At the pivotable relative to the crankshaft bearing plate 16, a guide coupling 22 is rotatably mounted, projecting from the radial arm 24.

The radial arm is connected via an arm 26a of a two-armed coupling member 26 with the driving lug 12. The other arm 26b of the coupling member 26 is connected via a further coupling member 28 in a joint 29 with the balancing mass component 14. The coupling member 28 protrudes, for example, in a radial slot (not shown) of the balance mass component 14 and is mounted therein by means of a pin. The pivot axes of the joints about which the coupling links are pivotable relative to each other and to the cam lug 12, the guide coupling 22 and the balancing mass component 14 are parallel to each other and parallel to the axes A and B.

By pivoting the bearing plate 16 to the motor housing fixed bearing with the axis B, the distance between the rotation axis C, by which the guide coupling 22 rotates and the axis of rotation A of the crankshaft change. To pivot the bearing plate 16, a total of 140 designated adjusting device is provided, which has an actuator 42 which is pivotally connected to an arm 44 which is rigidly connected to the end plate 16. Approximately in extension of the arm 44, the bearing plate 16 on its opposite side to another, rigidly connected to it arm 46, which is pivotable about the pivot axis B. The actuator 42 of the adjusting device 140 can be moved in a conventional manner by means of a hydraulic cylinder, an electric motor or otherwise according to Figure 7 in the vertical direction, the mobility is advantageously limited by stops 48 and 50.

The described device can build very compact in nested construction. The balancing mass component 14 is arranged between the guide coupling 22 and the middle entrainment approach 12 rotatably mounted on the crankshaft coaxially with the axis of rotation A of the crankshaft. The guide coupling 22 is rotatably mounted about the defined by the end plate 16 axis of rotation C. Axially next to the guide coupling 22 extend the arms 44 and 46 of the bearing plate 16. It is understood that the relative to the crankshaft eccentric pivoting of the bearing plate 16 and its adjustment can be ensured by other constructions, for example. By the fact that the bearing plate directly with a pin is mounted in the motor housing, which is arranged eccentrically to the axis of rotation of the crankshaft.

Figure 5 illustrates the state of the arrangement in which the axis of rotation C of the guide coupling 22 has a maximum distance from the axis of rotation A of the crankshaft 102. The connecting line between the axes of rotation A and C is advantageously approximately parallel to the direction of movement of the piston connected to the crankshaft 102, not shown, the internal combustion engine and coincides in the illustrated plan advantageously with the line of movement of the piston. Minor changes in direction of the connecting line during pivoting of the bearing plate 16 about the pivot axis B can be disregarded.

Figure 6 shows the state of the arrangement of Figure 5, in which the axes of rotation A and C coincide, that is, the state of maximum eccentricity of Figure 7 is adjusted to a concentric state in which the guide coupling 22 rotates coaxially with the crankshaft 10. In this state, the relative position between the driver lug and the coupling members 26 and 28 and the radial arm 24 remains constant, so that the balancing mass component 14 rotates at the same angular speed as the crankshaft 16.

The arrangement of the driving lug 12, the angled coupling member 26 and the coupling member 28 and the articulated connection between said components is such that with eccentric arrangement of the guide coupling relative to the crankshaft during a revolution of the crankshaft or the Mitnehmeransatzes 12, the coupling member 26 once relative to Mitnehmeransatz 12 is pivoted and thereby increases the angular velocity of the balancing mass component 14 against the angular velocity of the crankshaft once and correspondingly reduced once. In this way, rotational irregularities or speed fluctuations, as in the 2 ZyI mode of a four- 2 cylinder four-stroke piston internal combustion engine can be compensated by the arrangement of FIG. 5 is tuned to the engine such that in the phase in which the crankshaft would be accelerated by the fired cylinder, from the crankshaft in the balancing mass component by acceleration of the balancing mass component Even with constant rotating crankshaft energy is transferred from the crankshaft in the balancing mass component and in the phase in which the crankshaft only carries along the piston, or make compression work, the excess energy of the balancing mass component is fed back into the crankshaft. In this way, rotational nonuniformities of the crankshaft in the 2 ZyI mode are at least partially compensated, as can be seen from FIGS. 2 and 3. During the P (pause) phase of the 2 ZyI-P mode, the arrangement according to FIG. 5 is moved to the neutral or coaxial position according to FIG. 8, in which no active rotational irregularity compensation takes place from the balancing mass component 14, but the balancing mass component only in succession of its moment of inertia reduces rotational angular velocity variations.

Fig. 7 shows schematically a particularly simple embodiment of an adjusting device 140. The arm 44 of the bearing plate 16 (Fig. 1) is hingedly connected to a serving as an actuator shaft 42 of a piston 72 of a double-acting piston-cylinder unit 74 whose pressure chambers via two lines 76 and 78 are interconnected. In each of the lines 76 and 78, a check valve 80 and 82 is arranged, wherein the check valves 80 and 82 act in opposite directions to each other. Furthermore, a shut-off valve 84 or 86 is arranged in each of the lines. Due to the eccentric mounting of the bearing plate 16 act on the arm 44 during a revolution of the balancing component 14 alternately forces, which are directed according to the figures up or down. Depending on the opening of one of the shut-off valves 84 or 86, a hydraulic fluid in the piston-cylinder unit 74 can only flow from one pressure chamber to the other, so that an appropriate adjustment of the shut-off valves 84 and 86 results in one or the other direction without that to an external source of pressure medium is required. It is understood that it is ensured by a suitable hydraulic fluid refill that the lines and the piston-cylinder unit are constantly filled with hydraulic fluid without air. Referring again to FIG. 1, the overall function of the inventive device for compensating crankshaft rotational irregularities caused by selective firing of cylinders will be briefly explained again.

Depending on the position of the accelerator pedal 134 and the vehicle speed, the power requirement of the internal combustion engine is determined in the electronic control device 132 and the operating mode determined. As long as the internal combustion engine is operated with all cylinders, the adjusting device 140 is moved to the neutral position shown in FIG. When the mode 2 ZyI is decided, the compensation controller 132c of the controller 132 determines, in accordance with programs stored in its programs adapted to the respective internal combustion engine, the position of the adjusting device 140, i. the distance between the axes of rotation A and C (Fig. 5), in which by means of the balancing component 88, the Drehlei chförmigkeiten the crankshaft, which also depend on the position of the load actuator 138, are optimally balanced. In addition, the electronic machine control device 132d determines the speed curve with which the speed changes or fluctuations of the crankshaft 102, which are not compensated by the balancing mass component 88 and are compensated by the cylinder-selective operation of the internal combustion engine, are to be compensated via the adder gear 104 and controls the inverter control device 126 for a corresponding one Speed course of the electric machine 122 at.

When operating the internal combustion engine in the 2 ZyI-P mode, the above processes proceed in the same way, however, the adjusting device 140 in the P-phase (crankshaft rotation) between 720 ° and 1440 ° (FIG. 13) to neutral (axes of rotation A and C coincide).

The operation of the compensation device may be carried out as previously described pilot-controlled, or may additionally or exclusively controlled by the rotational irregularity of the crankshaft 102 and / or the drive shaft 106 are detected and fed to a controller which controls the adjustment 140 and the electronic control device 126 so in that speed changes of the crankshaft and the drive shaft are minimized. It is understood that the rotational irregularities of the crankshaft and the drive shaft detected by corresponding sensors are filtered unequally in accordance with the different periodicities of the irregularities to be eliminated, for example, changes of more than 20 ° in each case are required for the regulation of the adjusting device 140. shaft angle sliding averaged angular velocities, while for the control of the inverter 126, changes in the angular velocities are averaged over each 360 ° crankshaft rotation.

The mechanical part 120 of the balancer has been described in terms of its application to the 2 ZyI mode of a four-cylinder four-cycle internal combustion engine. By modifying the coupling between the rotation of the crankshaft, the guide coupling and the balancing mass component and, if necessary, a translation between the rotation of the crankshaft and the rotation of the cam projection 12 can be different modes compensate for different engines. For example, the coupling members 26 and 28 can be replaced by two coupling members, one of which connects the driving lug 12 with the radial arm 24 of the guide coupling and the other connects the radial arm 24 with the balancing mass component 14. In this way it can be achieved that the balancing mass component is accelerated and decelerated twice during one revolution of the crankshaft. In addition to the adjustability of the bearing plate 16, the balancing mass component 14 can be formed with a variable moment of inertia, for example, by containing two variable in a distance mass body. The electric machine 122 may be designed so that it not only serves to compensate for speed fluctuations, but also serves to regenerate braking energy in overrun mode or as a motor for driving or to assist the drive of the vehicle.

The electric part 124 has been explained above with reference to the electric machine 122 connected to the drive train via the adder gear 104. Alternatively, the electric machine 122 may also be non-rotatably connected to the crankshaft 102, wherein the adding gear 104 may then be dispensed with or merely forms a gear ratio between the rotor of the electric machine 122 and the crankshaft 102 or drive shaft 112. In this case, the torque of the electric machine 122 must each be controlled so as to produce the torque fluctuations around the average torque output that are effective after balancing the torque nonuniformities on the crankshaft 102 of the engine 100, exactly opposite torque fluctuations, thereby keeping the speed of the crankshaft 102 itself constant becomes. Also in this case, the control of the electric machine 122 may be controlled depending on the load and the respective operating mode of the internal combustion engine, or the operation of the electric machine 122 may be controlled by detecting the angular velocity changes of the crankshaft 102 and a controller that drives the inverter 126 to minimize the angular velocity changes.

The above-explained principle in which caused by relative firing of the cylinder speed fluctuations of the drive shaft of the vehicle be reduced by torque fluctuations of the crankshaft first mechanically reduced by energy exchange with the balancing mass component and remaining speed fluctuations are reduced by an electric machine, is also in internal combustion engines with a small number of cylinders without load control by means of selective ignition or injection possible. Thus, for example, in a single-cylinder four-stroke engine the torque fluctuations can be counteracted by means of the balancing mass component and remaining speed fluctuations can be smoothed with the electric machine. The coupling between the balancing mass component and the crankshaft can be adapted to the number of cylinders and operating mode (2 clock, 4 clock) of the internal combustion engine.

LIST OF REFERENCE NUMBERS

12 Driving lug 84 Stop valve

14 balancing component 86 stop valve

16 end shield 88 balancing mass component

20 through hole 90 unbalance

22 guide coupling 92 unbalance

24 radial arm 100 internal combustion engine

26 coupling member 102 crankshaft

26a arm 104 coupling device

26b arm 104a sun gear

28 coupling member 104b planet carrier

29 Joint 104c ring gear

40 adjusting device 106 output shaft

42 actuator 112 drive shaft 4 arm 120 mechanical part

46 arm 122 electric machine 8 stop 124 electrical part

50 stop 126 inverters

52 coupling member 128 energy storage

54 arm 132 electronic control device

56 arm 132a selective control device

58 Coupling link 132b Load control device 0 Piston 132c Compensation control device 2 Connecting rod 132d Electric machine control device 4 Peripheral toothing 134 Accelerator pedal sensor 6 Compensating mass component 136 Speed sensor 8 Peripheral toothing 138 Load actuator 2 Piston 140 Adjustment device 4 Piston / Cylinder unit 6 Line 8 Line 0 Check valve 2 Check valve

Claims

claims

A method of operating a vehicle powertrain having an internal combustion engine (100) having a plurality of cylinders in which pistons connected to a common crankshaft (102) operate, wherein the load matching of the internal combustion engine is at least partially accomplished by selectively selecting the cylinders according to a predetermined program be fired and reduced by the selective firing of the cylinder speed fluctuations of a rotationally driven by the crankshaft drive shaft (106) by means of an electric machine (122) which is operated in phases in which the rotational speed of the drive shaft would increase, and energy in an electric energy storage (128) feeds and in the phases in which the rotational speed of the drive shaft would decrease, is operated by a motor and at least a portion of the stored electrical energy as mechanical energy, characterized in that a) a movable Ausgleichsm Asesebauteil (14) is coupled to the crankshaft so that kinetic energy is supplied to the balancing mass component in predetermined phases in which the angular velocity of the crankshaft would increase without their coupling with the balancing mass component, and in predetermined phases in which the angular velocity of the crankshaft without their coupling with the balancing mass component would decrease, kinetic energy is withdrawn, even if the angular velocity of the crankshaft coupled to the balancing mass component is constant, and b) the remaining after reducing the rotational irregularities of the crankshaft, into the drive shaft (106) of the vehicle due to the selective firing the cylinder reaching speed fluctuations by means of the electric machine (122) can be reduced.

2. The method of claim 1, wherein the electric machine (122), the crankshaft (102) and the drive shaft (106) via an adding gear (104) are connected such that the drive shaft rotates at a speed corresponding to an addition of the speed of Crankshaft and the rotational speed of the electric machine corresponds, and the electric machine is controlled such that changes in rotational speed of the drive shaft due to speed fluctuations of the crankshaft is counteracted.

3. The method of claim 1, wherein the electric machine (122) is rotatably connected to the crankshaft (102) and is controlled such that its torque reduces speed fluctuations of the crankshaft.

4. The method according to any one of claims 1 to 3, wherein the coupling of the balancing mass component (14) with the crankshaft (102) and the operation of the electric machine (122) are controlled in dependence on the load of the internal combustion engine and the selective firing of the cylinder.

5. The method according to any one of claims 1 to 3, wherein the coupling of the balancing mass component (14) with the crankshaft and the operation of the electric machine in response to angular velocity changes of the crankshaft (102) are controlled.

6. The method of claim 2, wherein the coupling of the balancing mass component (14) with the crankshaft and the operation of the electric machine in response to angular velocity changes of the crankshaft (102) and the drive shaft are controlled.

7. A vehicle powertrain having an engine (100) with a plurality of cylinders in which pistons connected to a common crankshaft (102) operate, a selective controller (132) for controlling the engine (100) such that their cylinders are selectively fired in accordance with a program. a rotationally driven by the crankshaft drive shaft (106), an electric machine (122) which is operated in phases, in which the speed of the drive shaft would increase, regeneratively and energy into an electrical energy storage device (128) feeds and in the phases in which Speed of the drive shaft would decrease, is powered by the engine and at least a portion of the stored electrical energy as mechanical energy fed back, characterized in that a) a movable compensation mass component (14) is coupled to the crankshaft such that the balancing mass component in predetermined phases in which the angular velocity of the Crankshaft would increase without their coupling with the balancing mass component, kinetic energy is supplied, and kinetic in predetermined phases in which the angular velocity of the crankshaft would decrease without their coupling with the balancing mass component Energy is withdrawn, even if the angular velocity of the crankshaft coupled to the balancing mass component is constant, and b) the electric machine is controlled so that they remain in the drive shaft (106) of the vehicle as a result of the selective reduction after reducing the rotational irregularities of the crankshaft Firing the cylinder decreases speed fluctuations reduced.

8. The vehicle drive train of claim 7, wherein the electric machine (122), the crankshaft (102) and a drive shaft (106) of the vehicle via an adding gear (104) are connected such that the drive shaft rotates at a speed corresponding to an addition of the Speed of the crankshaft and the rotational speed of the electric machine corresponds, and the electric machine is controlled such that changes in rotational speed of the drive shaft due to speed fluctuations of the crankshaft is counteracted.

9. The vehicle drive train of claim 8, wherein the adding gear (104) is a planetary gear.

10. The vehicle drive train of claim 7, wherein the electric machine (122) is rotatably connected to the crankshaft (102) and is controlled such that its torque reduces speed fluctuations of the crankshaft.

1 1. A vehicle drive train according to one of claims 7 to 10, wherein the electric machine (122) via an inverter (126) with a serving as energy storage (128) capacitor is connected.

12. Vehicle drive train according to one of claims 7 to 11, wherein the crankshaft (102) via at least one coupling member (26 a) with a about an axis (A) of the crankshaft parallel axis (C) rotatable member (22) is coupled via at least one coupling member (26b, 28) is coupled to the balancing mass component (14).

13. Vehicle drive train according to claim 12, wherein an adjusting device is provided, with which the distance between the axis of rotation (C) of the rotatable member (22) and the axis (A) of the crankshaft (10) is adjustable.

14. Vehicle drive train according to claim 13, wherein a control device (132) is provided, with which the adjusting device (140) and the electric machine (122) depending on the selective firing of the cylinder and a load actuator 138) of the internal combustion engine (100) is controllable.

15. A vehicle drivetrain according to any one of claims 7 to 14, wherein the internal combustion engine is a 4-cylinder four-stroke internal combustion engine operable in a 4 ZyI, a 2 ZyI and a 2 ZyI-P mode.

16. Vehicle drive train according to one of claims 7 to 15, wherein the balancing mass component (14) with the crankshaft (102) is coupled such that its angular velocity is accelerated once during crankshaft rotation and decelerated.