DE102016211947A1 - Method for transmission and damping of torques - Google Patents

Abstract

A method for transmitting and damping an average torque with a superimposed alternating torque, in a torque transmission arrangement for a drive train of a motor vehicle comprising an input shaft rotatable about an input axis and an axis rotatable about an output range, wherein the average torque with the superimposed alternating torque along a torque path of the input portion of the torque transmitting assembly is rotated at an input speed about the axis of rotation and the output portion of the torque transmitting assembly with an output speed around the axis of rotation, wherein at least the input speed of a mean speed and a superimposed alternating component composed, wherein the alternating component can be described approximately by a superposition of periodic speed oscillations whose frequencies are substantially in an integer In relation to the ignition frequency, each of these periodic oscillations having a minimum and a maximum, wherein a slip arrangement in the torque path between the input range and the output range for transmitting the average torque with the superimposed alternating torque and for generating a rotational speed slip between the rotational speed ne and the rotational speed na in the torque path is provided, wherein the slip arrangement in the region of the maxima of at least one periodic oscillation component of the alternating component provides a maximum of external activation of the rotational speed slip and in the range of minima of at least one periodic oscillation component of the alternating component a minimum of external activation of the rotational speed slip.

Description

The present invention relates to a method for transmitting and damping an average torque with a superimposed alternating torque in a torque transmission arrangement for the drive train of a motor vehicle with an input area, and a subsequent output area.

From the prior art of DE 10 2008 009 135 A1 Such a method is known in a torque transmission arrangement for the drive train of a motor vehicle in which between a combustion engine and a change gear, a friction clutch is provided, and wherein the friction clutch is controlled so that a voltage applied to the friction clutch speed difference of a resonance speed width is reduced when starting, in Comparison without control.

A disadvantage of this method of the prior art that with this method, only the starting and the known by the starting chatter should be reduced. However, this method does not have the capability of dampening torsional vibrations caused by the internal combustion engine that occur in a permanent running condition.

Object of the present invention is therefore to provide a method for torsional vibration reduction of a torque transmitting device, which causes an advantageous, torsional vibration reduction especially after the starting.

This object is solved by the features of independent claim 1.

This is a method for transmitting and damping an average torque with a superimposed alternating torque, in a torque transmission arrangement for a drive train of a motor vehicle, comprising an input region rotatable about an axis of rotation (A) and an output region rotatable about an axis of rotation (B). wherein the average torque with the superimposed alternating torque is transmitted along a torque path from the input portion to the output portion, wherein the input portion of the torque transmitting assembly rotates at an input speed about the rotational axis (A) and the output portion of the torque transmitting assembly at an output rotational speed about the rotational axis (B); wherein at least the input speed of an average speed and a superimposed alternating component is composed, wherein the alternating component can be described approximately by a superposition of periodic speed oscillations whose F Frequencies are substantially in an integer ratio to the firing frequency, each of these periodic oscillations having a minimum and a maximum, wherein a slip arrangement in the torque path between the input and the output range for transmitting the average torque with the superimposed alternating torque and for generating a rotational speed slip between the Speed ne and the speed na is provided in the torque path, wherein the slip arrangement in the region of the maxima of at least one periodic oscillation component of the alternating component a maximum of ex-ternal activation of the rotational speed slip and in the range of minima at least one periodic oscillation component of the alternating component a minimum of external activation of Speed slip provides. In this case, further torsional vibration damping units such as, for example, a first and / or a second spring set as well as a damping unit can be connected in series between the input area and the exit area and before the slip arrangement. This is particularly advantageous because the alternating torques that come from the input area, for example an internal combustion engine, are prefiltered. The slip arrangement aims to reduce the remaining remaining alternating moments, in the optimal case even to set to "zero". In order to achieve this, the method according to the invention provides that, in the event that a maximum external activation of the slip arrangement takes place in the region of a maximum of a periodic oscillation of the superimposed alternating torque, more slippage is permitted, and in the region of a minimum of a periodic oscillation of the superimposed alternating torque minimal external activation of the slip arrangement is to allow less slippage. This means that the slip arrangement, which can be formed for example by a slip clutch, for example a multi-plate clutch, receives a hydraulic signal from the external activation in the form of a lower hydraulic pressure, which can result in a reduction of a contact force on the multi-plate clutch and thus a slip increase ie an increase in the speed difference results. In the case of slip reduction, the external activation should give a hydraulic signal to the slip clutch in the form that a hydraulic pressure is increased and thus the contact pressure on the slip clutch is also increased, resulting in a slip reduction in the slip clutch. As a result, the maximum in the superimposed alternating moment can be counteracted. The external activation to achieve the slip reduction or the slip increase can also be referred to as slip modulation. Here is the frequency of Slip modulation depending on the use of the drive unit, for example, the internal combustion engine. When using a four-stroke internal combustion engine, a frequency range of 23 hertz to 60 hertz, using a four-cylinder cycle engine, the use of a frequency range of about 33 to 66 hertz, and using a six-cylinder four-stroke internal combustion engine, the use of a frequency range of 50 to 100 hertz advantageous.

It can further be provided that the external activation of the slip arrangement is effected by a ball ramp mechanism, which is connected downstream of a spring set.

Also, an activation of the ball ramp mechanism is effected by a twist angle on the spring set.

Furthermore, it may be advantageous for the ball ramp mechanism to be in operative connection with a lifting piston of a hydraulic cylinder.

A favorable embodiment provides that the reciprocating piston is in operative connection with a working chamber of the slip arrangement.

Also, the working chamber is operatively connected to a release piston of the slip assembly.

In a further advantageous embodiment, the ball ramp mechanism is suitable for providing on the slip arrangement a modulation range of 23 to 50 Hz or a range of 33 to 66 Hz or a range of 50 to 100 Hz.

Also, the slip arrangement can be used as a starting element.

But it can also be provided in addition to the slip arrangement, a starting element.

It may also be advantageous if the slip arrangement and / or the starting element designed as a friction clutch, or as a multi-plate clutch, or as a hydrodynamic clutch, or as a clutch in hybrid drives, or as a double clutch or a triple clutch, or as a brake in Connection is made with a planetary gear.

Also, the ball ramp mechanism may be implemented as a threaded spindle mechanism.

Furthermore, the threaded spindle mechanism can be in direct operative connection with the slip arrangement.

It is also advantageous if the threaded spindle mechanism is suitable for providing on the slip arrangement a modulation range of 23 to 50 Hz or a range of 33 to 66 Hz or a range of 50 to 100 Hz.

Also, the slip arrangement can be used as a starting element.

Furthermore, in addition to the slip arrangement, a starting element can be provided.

It can be advantageous if the slip arrangement and / or the starting element as a friction clutch, or as a multi-plate clutch, or as a hydrodynamic clutch, or as a clutch in hybrid drives, or designed as a double clutch or a triple clutch, or as a brake in combination is executed with a planetary gear

Also, the axis of rotation (A) and the axis of rotation (B) can be coaxial or that the axis of rotation (A) and the axis of rotation (B) are offset.

In the following, the invention will be explained in more detail with reference to illustrations. The embodiments illustrated in the drawings represent only preferred embodiments and are not intended to define the scope of the invention. This is defined solely by the appended claims.

It show in

1 : A schematic representation of a drive train as prior art

2 : advantageous schematic representation of a drive train

3 : Diagram of a deflected moment course

4 : advantageous schematic representation of a drive train

5 : Preferential topology schematic

6 : Schematic diagram of a slip clutch

7 : Diagram of a deflected moment course

8th : Chart slip speed over time

9 : Diagram friction coefficient over slip speed

10 : Diagram friction coefficient over time

11 : Diagram sinusoidal course of Fa

12 : Diagram of the trapezoidal course of Fa

13 : Diagram Sinusoid of Fa with higher order

14 : more diagrams

15 : Diagram input speed at the slip arrangement in one operating point.

16 : Diagram of coefficient of friction over slip

17 - 24 : further embodiments of the invention

Hereinafter, identical or functionally equivalent components are denoted by the same reference numerals.

First of all to the 1 It should be mentioned that today's torsional vibration decoupling systems for passenger cars in addition to spring-mass arrangements, for example, ZMS, also provide speed-adaptive absorbers. In addition, and at least in drive trains with wet-running starting element, a reduction in the torque fluctuations of the internal combustion engine can be carried out via a slip in the starting element. The technique used here, in which a slip controller sets a predetermined average slip speed, is referred to below as "active slip mode 1". In the following, a method for controlling a clutch in a passenger car drive train is presented, which is referred to as "active slip mode 2" and should in particular enable a significantly better decoupling to be achieved with the same average slip speed and thus the same friction losses than with one Prior art slipping clutch, or at least an equivalent level of decoupling as conventional systems using lighter and less expensive pre-decoupling components, such as spring sets and absorbers.

The 1 shows a torque transmission arrangement 1 in an automated drive train of a motor vehicle according to the prior art, which is a torsional vibration damping unit 15 with speed-adaptive absorber 6 contains. In this case, the relevant masses, stiffnesses and the starting element are arranged as follows, wherein the representation is made only up to and including the transmission. The residual drive train is hidden. A lockup clutch 72 is at the entrance 25 the torsional vibration damping unit 15 arranged.

The speed-adaptive absorber 6 is at an intermediate mass 3 between a first spring set 10 and a second spring set 20 placed. This topology has the following drawbacks with respect to torsional vibration decoupling.

Will the lockup clutch 72 operated with a clutch slip, this reduces the torque fluctuations, which in the torque transmission arrangement 1 be directed. Characterized in that the speed of the components on the output side of the lockup clutch 72 , and thus also those of the Tilgers 6 to the controlled slip speed is lower than, for example, an engine speed of the Antriebsaggregeates 50 , agrees the vote of the absorber 6 on the engine order no longer, so that it works worse and worse with increasing slip. The task of the second spring set 20 it is a spring stiffness between the relatively high inertia of the absorber 6 and also the relatively heavy gearbox 33 display. Would the absorber 6 directly on a transmission input shaft 100 be connected, this would result in the usual moment of inertia and wave stiffness that form so-called nodes. This means that at certain, even gear-dependent speeds, the absorber in the vibration system does not experience excitation and thus set up no reaction torque and therefore can not contribute to rotational nonuniformity decoupling. This manifests itself then at the appropriate speed by a significant increase in the remaining rotational nonuniformity, see also in the 3 , the dashed line in the upper speed range. Although this is prevented with the existing topology, the relatively high mass moment of inertia of the intermediate mass can be a factor 3 and the Tilgers 6 , in conjunction with the stiffness of the spring sets 10 and 20 form an intermediate mass resonance unfavorable in terms of rotational nonuniformity decoupling.

The 2 shows a more favorable topology of the components, which also in the 1 were shown. This is characterized by the fact that the second spring set 20 primary side to the absorber 6 is arranged, resulting in the following advantages. On the one hand is due to a reduced sum stiffness of the two spring sets connected in series 10 and 20 a pre-decoupling in front of the absorber 6 improved, so that it can be made smaller and the system is already working supercritically at lower rpm, good to see in the 3 , the dashed and dotted line. Next falls the intermediate mass 3 without the connection to the absorber 6 significantly smaller, so that no disturbing intermediate mass resonance arise in the operating range. Next is the lockup clutch 72 on the output side of the torque transmitting device 1 arranged between the absorber 6 and the transmission 33 , This is advantageous because the coupling slip the order tuning of the absorber 6 is not affected. Also, by the clutch slip of the lockup clutch 72 reduces or prevents the formation of the vibration nodes described above, as in the 3 shown with the dotted line.

The in the 2 shown arrangement used for reasons of better comparability in principle the same schematic design of and number of subassemblies, especially spring sets, as in the 1 described.

However, this is only an example. Functionally, for example, other embodiments of the torsion damper 10 . 20 possible, inter alia, as a single or multi-row DMF. Also the absorber 6 can be carried out in different ways, with constructions as speed-adaptive absorber according to the principle Sarrazin, Salomon or DFTvar are particularly advantageous.

The 3 shows the deflected torque over the speed of a torque transmission system according to the prior art, a variant without slip and a variant with slip Mode 2.

The 4 shows another topology arrangement, as already in the 1 and 2 described, but with only one spring set 10 , here as a dual-mass flywheel with a single-row spring set.

The 5 shows an advantageous topology for torsional vibration reduction in the drive train. In this sense, rotational nonuniformity decoupling refers to a system which provides rotational nonuniformity prior to the slip clutch 30 reduced. This can consist of an arrangement of torsion springs, masses and absorbers as in the concrete example above. However, other principles are possible, such as rotational nonuniformity decoupling with two parallel torque transmitting paths and a coupling arrangement, a gas spring torsional damper, or a centrifugal force spring arrangement.

For the required slip-capable coupling 30 It can also be a start-up clutch at the same time. But this is not absolutely necessary. The starting clutch may otherwise be placed at another arbitrary position of the drive train. In the same way, the slip-capable clutch can also be one or more clutches of the transmission, which solve each gear, tasks in the transmission circuit and / or rotational nonuniformity decoupling by slip. The type of transmission, for example as an automatic transmission (AT), dual-clutch transmission (DCT), automated manual transmission (ASG), continuously variable or manual transmission (MT) and the design of the drive train as a front Rear or all-wheel drive, also in hybridized design, are arbitrary. Especially with MT and DCT transmissions, the topology described is already standard, but not in combination with AT gearboxes. However, especially in MT transmissions, but also in dry-running DCT transmissions the starting clutch used there is not suitable to take a permanent function of slip for rotational nonuniformity decoupling. In this respect, the proposed structure is new for these powertrains.

The 6 shows simplified a schematic diagram of a slip-capable coupling 30 after an improved procedure, the clutch slip Mode 2.

With the topology already described can at the same stiffness values of the spring set 10 . 20 a significantly improved decoupling can be achieved even at low speed and already clutch slip Mode 1 effectively works to further improve the decoupling or to avoid vibration nodes. However, the clutch slip generally leads to friction losses, which can assume unacceptable values at high engine torque and high slip speed. Limiting here are the increasing fuel consumption and thus CO2 emissions and the generated frictional heat, which must be dissipated.

The aim of the present invention is to increase at low slip speed, the decoupling effect of the slip.

r

= mittlerer Reibradius

μ

= Reibwert der Kupplungsbeläge, welcher von der Schlupfdrehzahl n_Schlupf abhängt.

This is achieved by actively modulating the torque that can be transmitted by the clutch. This method is therefore called active slip mode 2. In this case, F0 is a force, which is regulated by a slip controller, by a certain average speed difference between an input side 31 the slip arrangement 30 and a home page 32 the slip arrangement 30 to reach. In a stationary operating point, F0 can be regarded as constant. The transferable moment of the clutch 30 is calculated so far M_üb = F_0 · r · μ (n_slip) With

r

= mean friction radius

μ

= Coefficient of friction of the clutch linings, which depends on the slip speed n_slip.

Fa (α,) is an additional force whose amplitude is dependent on a reference angle α and a phase shift β. The dependence can be given for example via a sine function. As a reference angle, for example, the crankshaft position comes into question. For a vote on the main engine order in a 4-cylinder 4-stroke engine, this would mean: F_a (α, β) = F_a * sin (2α + β)

The transferable moment is calculated as follows:

In the 7 It can be seen what effect the modulation of the clutch torque causes the torsional vibration decoupling of the engine main order. Compared to slip mode 1, the slip mode 2 significantly reduces the rotational nonuniformity again, with the same average slip speed and correspondingly equal friction losses.

The 8th . 9 and 10 illustrate the derivation of the functioning of the active slip Mode 2. Due to non-linear relationships and the non-harmonic excitation in the real drive train, the mode of operation of the modulation of the transmittable clutch torque with respect to the DU decoupling can be clearly derived only under greatly simplified conditions.

For this purpose, one in the main order, here the 1st engine order, assumed a purely sinusoidal rotational irregularity at the input side of the clutch. In this example, with a constant coupling force F0, a mean slip of 5 rpm occurs, which oscillates around the mean value with an amplitude of 4 rpm, cf. 8th ,

The course of the coefficient of friction of the slip clutch on the slip is linearized in this area, dargestelllt with the solid line, in the 9 ,

Thus, there is also a sinusoidal course over time for the coefficient of friction 10 , The average coefficient of friction here is μ_0 = 0.105 and the amplitude μ_a = 0.012.

For the transmittable moment, the following applies to modulation in the main order:

The angle α is calculated here as α = 2 · π · n · t with n = rotational speed t = time

With an optimal phase shift β = 180 ° = π, sin (α + π) = -sin (α) follows by multiplying M_üb by:

folgt:

With

follows:

• 0. Ordnung: F_0 μ_0 – (F_a μ_a)/2 mittleres Moment Um das gleiche mittlere übertragbare Moment zu erhalten, sind für unterschiedliche Subtrahenden (F_a μ_a)/2 unterschiedliche Kräfte F_0 notwendig (wird durch Schlupfregler nachgeregelt).
• 1. Ordnung: (F_0 μ_a – F_a μ_0)sin (α) Hauptordnung in diesem Beispiel Lässt sich unter den vereinfachten Annahmen bei Wahl von F_a =(F_0 μ_a)/μ_0 komplett auslöschen! Hierin ist der Effekt der Erfindung begründet!
• 2. Ordnung: (F_a μ_a)/2cos (2α) Durch die Modulation entsteht eine neue Ordnung mit doppelter Modulationsfrequenz. Die Amplitude dieser Ordnung ist jedoch vergleichsweise gering und zudem werden höhere Ordnungen vom Antriebsstrang besser gedämpft als niedrige, so dass der positive Effekt der Reduzierung der Hauptordnung überwiegt. Es handelt sich bei dieser Herleitung um ein stark vereinfachtes Modell. Aufgrund der abweichenden Bedingungen in der Realität, ist zwar mit diesem Verfahren praktisch keine vollständige Auslöschung der Haupt-Motorordnung möglich, jedoch eine deutliche Reduzierung, wie in der 7 zu sehen ist.

The summands in the square brackets of this term can be assigned to different orders:

• 0th order: F_0 μ_0 - (F_a μ_a) / 2 mean torque In order to obtain the same average transmittable torque, different forces F_0 are necessary for different subtrahends (F_a μ_a) / 2 (is adjusted by slip control).
• 1st order: (F_0 μ_a - F_a μ_0) sin (α) Main order in this example Can be completely canceled under the simplified assumptions when choosing F_a = (F_0 μ_a) / μ_0! Herein is the effect of the invention justified!
• 2nd order: (F_a μ_a) / 2cos (2α) The modulation creates a new order with twice the modulation frequency. However, the amplitude of this order is comparatively low and, in addition, higher orders are better damped by the drivetrain than low, so that the positive effect of reducing the main order outweighs. This derivation is a much simplified model. Due to the different conditions in reality, although this method virtually no complete extinction of the main engine order possible, but a significant reduction, as in the 7 you can see.

The function of the clutch slip with active modulation, ie clutch slip mode 2, is determined by the following parameters.

For one, this is the waveform. The optimal course of the transmissible clutch torque over time depends on the course of the rotational nonuniformity of the main order at the clutch input. In the previous example, the assumed excitation was purely sinusoidal and the optimum course of the modulated coupling force was also. In a real drive train, the already decoupled main order of the alternating torque at the clutch input has an at least approximately sinusoidal course, so that here the modulation of the clutch torque can be described via a sine function to achieve good results, see in the 11 , However, other harmonic as well as nonharmonic functions may be taken as basis, such as a trapezoidal course, seen in the 12 , Likewise, the waveform can be optimized to reduce multiple engine orders. In a simple case, this is possible because the modulation is due to an overlay two sine waves is described, wherein the one sine wave, for example, the ignition frequency and the other has twice the ignition frequency.

However, the distribution of the actuation force of the clutch into a predetermined by the slip control, constant in the steady-state operating force F0, and a dynamic force Fa for the modulation of the transmissible torque, but is primarily a thought model to describe the principle of effect of the invention. It is a matter of constructive implementation, whether actually two forces are superimposed, z. Example, in the sense of two separate actuators, whether the force which a single actuator applies to the clutch, is varied according to whether mixed forms are used.

Crucial for the process is only that the transmittable torque of the clutch is dynamically changed in a suitable form and with suitable parameters. For a vote on the main engine order, the modulation frequency must correspond to the ignition frequency of the internal combustion engine. Thus, it increases depending on the engine speed. For a 3-cylinder 4-stroke engine results, for example, for the speed range from 1000 to 2000 rpm a necessary modulation frequency of 25 to 50 Hz. In engines with cylinder deactivation, it is particularly advantageous if the control of the slip operation switching between the orders of Full and shutdown operation allows. Likewise, an interpretation to higher orders, or a combined interpretation of several orders is possible.

The optimum phase angle of the modulation is 180 ° with respect to the oscillation of the input rotational speed of the slip arrangement, as already described above in the theoretical derivation of the function. Phase shifts in the range of 180 ° ± 45 ° are particularly advantageous. If the phase shift is too small, the rotational nonuniformity increases, which becomes maximum when the phase is equal.

• 1. Spalte: Schlupf Mode 1
• 2. Spalte: Schlupf Mode 2 – Phasenlage in einem günstigen Bereich
• 3. Spalte: Schlupf Mode 2 – Phasenlage in einem ungünstigen Bereich

The 14 shows different sizes in the drive train of a motor vehicle according to the 4 , for three different cases:

• 1st column: Slip Mode 1
• 2nd column: Slip mode 2 - phase position in a favorable range
• 3rd column: Slip mode 2 - phase position in an unfavorable range

In the top line is the speed at the input area 31 the slip coupling 30 shown. Due to the rotational nonuniformity of the internal combustion engine, the speed varies despite pre-decoupling by, for example, a DMF and a speed-adaptive absorber 6 , to the arrangement compare the comments in the 5 and 6 to a medium speed, here ~ 1205rpm. For the sake of clarity, in addition to the raw signal, the oscillation of the rotational speed in engine ignition order is also shown. This can be determined by means of fast Fourier transformation from the time course of the overall oscillation.

In the second line, the slip speeds ns are between the input side 31 and home page 32 the slip clutch 30 , as well as the active moment Ma shown. The active moment Ma is directly proportional to the above-mentioned active force component Fa and is calculated as: M_a = F_a · r · μ

With active slip Mode 1 in the first column, the force Fa and thus also the moment Ma is equal to zero. The self-adjusting course of the slip is thus the result of the operating force F0 set by the slip control in order to obtain a mean slip (here 5 1 / min), the course of the excitation, ie. H. the speed or torque fluctuation on the clutch and the course of the friction coefficient of the clutch over the slip speed.

In the active slip mode 2 in the second and third column, a sinusoidal profile of the force component Fa or of the active torque Ma is predetermined with a specific amplitude and with the ignition frequency of the internal combustion engine.

In the second column, the phase angle of the course of the active torque Ma compared to the course of the rotational speed before the clutch in ignition order in the diagram about 180 °. In other words, in the time ranges in which the speed fluctuation in ignition order has minima, the active moment Ma has maxima and vice versa. This represents an optimized tuning of the active slip mode 2.

The third column shows an unfavorable case in which the active torque is approximately in phase with the speed at the input area of the clutch.

The graphs in the third row show the torque transmitted by the clutch, again as the original raw signal and as its component in engine firing order. It can be seen that with the active slip Mode 2 with optimized phase position, see column 2, the nonuniformity of the moment in the engine main order is almost completely smoothed. With the unfavorable phase position, see column 3, the amplitude of the torque nonuniformity compared to the active slip mode 1, see column 1, even increased.

The phase of the modulation need not be exactly 180 ° with respect to the speed at the input of the slip device to achieve a positive effect. In order to achieve an improvement over the active slip mode 1, however, it is advantageous if the phase shift is in the range 180 ° ± 45 °.

The 15 shows the course of the speed in the entrance area 31 the slip arrangement 30 as well as in the 14 , middle column, top line shown, for a static operating point.

The input speed (ne) has an average value (nem), here 1205 1 / mm, around which an alternating component (new), not specifically shown here, since congruent with the course of ne, oscillates. The course of the alternating component depends essentially on the nature of the internal combustion engine 50 , in particular the number of cylinders, and the pre-decoupling. The alternating component can be described by means of fast Fourier transformation (FFT) approximately as a superposition of sinusoidal oscillations (newp_i). The lowest frequency of such a periodic partial oscillation of the alternating component is the ignition frequency of the engine. The frequencies of other harmonic oscillations are in an integer ratio to the firing order. In a real drive train and vibration components with non-integer reference to the ignition frequency can occur, but these are neglected here. In the 15 For example, the periodic alternating components in the engine main order (newp_1) and in the double engine main order (newp_2) are shown. The amplitudes of the alternating components fluctuate between a minimum (newp_i_Min) and a maximum (newp_i_Max). The course of such an alternating component is a reference variable for the phase shift β of the modulation of the activation of the slip arrangement in order to achieve a reduction of the rotational nonuniformity in the corresponding engine order.

There is an optimum amplitude of the active torque Ma, which depends mainly on the average engine torque 0th order and the average slip speed. There is an approximately linear relationship between the optimal amplitude and the mean moment at different load conditions.

Particularly suitable are amplitudes of the modulation of the torque transferable by the slip arrangement between 5 and 15% of the average engine torque.

The effective friction coefficient, in particular a wet-running friction clutch, as is commonly used in motor vehicle drive trains, depends on the instantaneous differential rotational speed between the input and output of the clutch. Usually, the course is significantly adjusted by additives in the oil, material and geometry of the pads so that there is a degressive slope above the slip speed. A usual Reibwertverlauf is in the 16 shown.

For the slip clutch proposed here, it is particularly advantageous if the coefficient of friction lies in a range between 0.05 and 0.15 and rises sharply up to a very high slip speed. Slopes of the coefficient of friction over the rotational speed between 0.001 / rpm and 0.005 / rpm in a slip range up to 30 rpm are particularly favorable. The average slip rotational speed is regulated by a slip regulator.

Since slippage generally causes friction losses, which must be dissipated in the form of heat energy, the lowest possible average slip speed should be aimed for. Favorable for the actively modulated slip average slip speeds are less than or equal to 30 rpm, more preferably less than or equal to 10 rpm.

The active slip Mode 2 brings a significant improvement in decoupling, especially in the low and medium speed range, compared with the known slip Mode 1. This has the advantage of lower cost in the control and in the operation of the slip clutch. In particular, at high speed and depending on the vibration behavior of the drive train, no slip may be necessary in certain operating conditions for the DU decoupling.

It therefore makes sense to implement a demand-oriented operating strategy. This can be based on the following scheme: Low speed Average speed High speed High load Slip Fashion 2 Slip Fashion 2 Slip Mode 1 Medium load Slip Fashion 2 Slip Mode 1 no slippage Low load Slip Mode 1 no slippage no slippage

Special operating conditions, such as vibration dependent nodes, starting or resonances, are also to be considered.

The 17 assumes that one before a slip arrangement 30 arranged damper 10 a DUE facility, e.g. B. if necessary, several cascaded dampers advantageously the last before the friction clutch 30 , in the known manner passes through a twist angle, which corresponds to the transmitted torque and superimposed in addition to the remaining here remaining rotational irregularities.

If one transmits the twist angle by means of a suitable device, for example a ball ramp here 70 on a piston 72 an axially acting hydraulic cylinder 78 Alternatively, for example, the principle of an axial piston pump or a rotary cylinder is conceivable, so can the verdrehwinkelabhängig won or lost in reverse direction effective volume or the resulting pressure pulsation in the on-control or pressurization of the clutch 30 be included.

The volume and pressure changes in this system can be high-frequency over a short distance in the workspace 39 be guided and act there in the manner of the clutch torque that torque peaks in the shaft before the clutch 30 taking into account the boundary conditions of the coupling 30 (Reibwertverlauf, mean friction radius, piston surface, etc.) lead to a slight increase in the clutch slip and thus to even out the torque transmission to the shaft behind the clutch 30 can be used.

Spontaneous changes in the requested by the driver's foot on the accelerator pedal torque, which is also the angle change of o. A. lead last damper, are already detected by the system upon detection of the driver's request and taken into account by the control and the HPU by withdrawing or increasing the predetermined system pressure caused by the Fahrmomentänderung volume adjustment of the actuating cylinder.

In this case, such an effective system on the complete friction clutch 30 act or alternatively only individual friction elements of the clutch 30 or even apply individual additional separately provided friction plates. The particular advantage of this self-sufficient system, so sensor system and actuator combining system is that the drive signal and the energy can be obtained directly from the transmitted torque, so additional sensations, signal processing and energy supplies are not required.

The consideration of variable and also spontaneously changing torque requirements by the driver can be detected in the already existing system elements and taken into account in the control routines. In this sketch it is shown that when a torque peak occurs, the control cylinder briefly increases its volume, thus lowering the support pressure in antiphase action and thus somewhat reducing the clutch pressure in the actuating cylinder of the clutch. The consequence is an increase in clutch slip proportional to the magnitude of the pressure peak which has occurred, and thus the isolation of the torque peak occurring before the clutch from the drive train behind the clutch.

It is of crucial importance that the volume swallowed by the control cylinder as a result of the torque peak can not be refilled immediately from the HPU. That's the distance from the steering cylinder 78 to the clutch 30 short and little throttling, ie high-frequency (eg: ... 100 Hz suitable), while the Nachfüörderleitung of the HPU for coupling rather low frequency (low-pass) should be designed (eg <2 ... 5 Hz).

Depending on whether the complete twist angle linear or z. B. higher torques are to be included in a special way in the clutch pressure modulation, the ball ramps evenly or z. B. be executed exponentially rising.

The 18 shows a torque transmission arrangement 1 for an automated hybrid transmission 2 , Here, a basic structure is as follows in an order of a torque path M, the average torque Mm superimposed with alternating moments Mw of an input range 25 , which can be formed by an internal combustion engine, for example, to an output area 35 , which can be formed for example by an output shaft of a transmission. The torque transmission arrangement 1 is divided into three areas. A first room area 17 which also acts as a drying room 24 can be designated, a subsequent second space area 19 that also acts as a wet room 26 can be designated and a subsequent third room area 28 that also acts as a wet room 29 can be designated. A first torsion damper 10 is located in the first room area 17 and is designed as a dual mass flywheel. This can be operated with a grease filling and is preferably in the drying room 24 in which no viscous medium is contained, placed. After the dual mass flywheel 10 is a speed-adaptive absorber 6 in the second room area 19 arranged. This is located in the oil mist-containing working space 26 ,

An advantage of this variant is an efficient and cost-effective space utilization, as well as a resulting high quality of the decoupling of rotational irregularities, which are initiated by the drive unit, such as the internal combustion engine. The following is a slip arrangement 30 arranged in the form of a multi-plate clutch, wherein an inner disc carrier 27 rotatably with the Tilgereinheit 6 connected is. An outer disc carrier 82 the slip arrangement 30 is non-rotatable with the exit area 35 connected. Next is with the outer disk carrier 28 a rotor 42 an electric drive unit 91 , which is used here as a hybrid engine connected. A release piston 38 the slip arrangement 30 is pressurized by a hydraulic working chamber, not shown here. A ball screw unit 90 between an input element 71 and an output element 72 of the spring set 10 is operatively connected, transmits a relative rotation of the input element 71 to the starting element 72 as an axial displacement of the piston. The ball screw 90 can implement depending on the design and different gradients with their transitions to translate the angle of rotation between the primary side in the torsion damper and the secondary side or the same rotating parts in an axial movement. The connection here, for example, via a leaf spring to the crankshaft, which operates in a low-friction area friction, the large swing angle over the entire torque range and slightly beyond shifts in a Profliverzahnung. Thus, the inner displacement piston moves depending on the selection of the direction of rotation z. B. during compression of the damper in the direction of the engine, resulting in a pressure drop in the piston chamber and thus a torque drop. So the pressure peak can be used to modulate the clutch slip. For larger changes in driving torque, depending on the driver's request, as described above, the control unit and the hydraulic unit would have to compensate accordingly.

Depending on the desired phase shift z. B. by influences of the transmission path could be the oscillation amplitude z. B. by 180 °, by modifying the translation or movement direction by the pitch selection on the piston

The 19 to 25 show further embodiments of the method according to the invention.

If the axial KW pulsations coincide with the torque oscillation, then the inactivation for the slip pulsation could decrease directly axially here. The spring is used to always apply the piston to the KW and so have no additional idle stroke in the operating path. This could also be represented by a slightly higher preload pressure.

The torque modulated by the pressure modulation slip couplings 30 , This applies across figures, for example, a disconnect couplings in hybrid systems, which can be arranged in the moment flow, for example, behind a DUE system and also, for example, radially within the electrical unit, or also drive-compatible clutches arranged comparable, for example, in the design of a hydrodynamically cooled clutch (HCC) or a dual clutch or a triple clutch, which combines the functions of dual clutch and K0, or one or, depending on the torque flow in the transmission in the various gears, if necessary, several internal transmission clutches or brake, which are operated actively slipping. One of the clutches or brakes used can be an integrated starting element. In the case of several internal clutches or brakes, depending on the type of actuator, there may be an increased constructional effort to be considered.

Another conceivable is a ball ramp mechanism, which is not hydraulically but mechanically supported against the piston and thus the torque irregularity in high-frequency restoring forces, acting against the actual piston force converts. The variable caused by the base moment Reset path is taken up by a spring arranged between ball ramp mechanism and piston. The conditional by the spring bias acting on the piston increased restoring force can be compensated by increased control pressure in the piston chamber.

LIST OF REFERENCE NUMBERS

1

Torque transmitting assembly

2

primary mass

3

intermediate mass

4

secondary mass

6

Tilgereinheit / speed-adaptive Tilgereinheit / variable speed-proof Tilgereinheit / Tilger

7

Transmission input shaft

10

1. Spring set / torsion damper / dual mass flywheel

15

Torsional vibration damping unit

17

first room area

19

second room area

20

2. Spring set torsion damper / dual mass flywheel

21

active pulsator

24

drying room

26

humidor

27

Inner disk carrier

28

third room area

29

wet room

30

slip arrangement

31

Entrance part slip arrangement

32

Output part slip arrangement

33

gear unit

35

output range

36

pressure line

38

release piston

39

working chamber

40

external activation

45

external activation

42

rotor

50

hydraulic unit

52

High-pressure accumulator

53

hydraulic pump

70

Ball ramp mechanism

71

Eingangselemenent

72

reciprocating

73

output element

78

hydraulic cylinders

82

External disk carrier

85

cover

90

Ball screw mechanism

91

electric drive unit

M

torque path

mm

average torque

mw

superimposed alternating moment

ne

Input speed

n / A

Output speed

nm

medium speed

ns

Speed slip

newp

superimposed alternating component

newpi

periodic vibrations

newp_i_Min

Minimum of a periodic vibration

newp_i_Max

Maximum of a periodic oscillation

A

axis of rotation

B

axis of rotation

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102008009135 A1 [0002]

Claims (17)

Method for transmitting and damping a mean torque (Mm) with a superimposed alternating moment (Mw), in a torque transmission arrangement ( 1 ) for a drive train of a motor vehicle, comprising an input area rotatable about an axis of rotation (A) ( 25 ) and an about an axis of rotation (B) rotatable output range ( 35 ), wherein the mean torque (Mm) with the superimposed alternating torque (Mw) along a torque path (M) from the input area (M) 25 ) to the exit area ( 35 ), the input area ( 25 ) of the torque transmission arrangement ( 1 ) with an input speed (ne) about the axis of rotation (A) and the output range ( 35 ) of the torque transmission arrangement with an output speed (na) about the rotation axis (B) rotates, wherein at least the input speed (ne) of a mean speed (nem) and a superimposed alternating component (newp) composed, wherein the alternating component (new) approximately by a Overlapping periodic speed oscillations (newp_i) can be described, the frequencies (f) are substantially in an integer ratio (i) to the ignition frequency (Zf), each of these periodic oscillations (newp_i) a minimum (newp_i_Min) and a maximum (newp_i_Max) having a slip arrangement ( 30 ) in the torque path (M) between the input region ( 25 ) and the exit area ( 35 ) for transmitting the average torque (Mm) with the superimposed alternating torque (Mw) and for generating a rotational speed slip (ns) between the rotational speed ne and the rotational speed na in the torque path (M), characterized in that the slip arrangement ( 30 ) in the region of the maxima (newp_i_Max) of at least one periodic oscillation component (newp_i) of the alternating component (newp) a maximum of an external activation ( 40 ) of the rotational speed slip (ns) and in the region of the minima (newp_i_Min) of at least one periodic oscillation component (newp_i) of the alternating component (new) a minimum of an external activation ( 45 ) of the rotational speed slip (ns). Method according to claim 1, characterized in that the external activation ( 40 ; 45 ) of the slip arrangement ( 30 ) of a ball ramp mechanism ( 70 ), which is a spring set ( 10 ) is connected downstream. Method according to claim 2, characterized in that an activation of the ball ramp mechanism ( 70 ) by a twist angle on the spring set ( 10 ) he follows. Method according to one of claims 2 or 3, characterized in that the ball ramp mechanism ( 70 ) in operative connection with a reciprocating piston ( 72 ) of a hydraulic cylinder ( 78 ) stands. Method according to Claim 4, characterized in that the lifting piston ( 72 ) in operative connection with a working chamber ( 39 ) of the slip arrangement ( 30 ) stands. A method according to claim 5, characterized in that the working chamber in operative connection with a release piston ( 38 ) of the slip arrangement ( 30 ) stands. Method according to one of claims 2 to 6, characterized in that the ball ramp mechanism ( 70 ) is adapted to the slip arrangement ( 30 ) to provide a modulation range of 23 to 50 Hz or a range of 33 to 66 Hz or a range of 50 to 100 Hz. Method according to one of claims 1 to 7, characterized in that the slip arrangement ( 30 ) as a starting element ( 60 ) is used. Method according to one of claims 1 to 7, characterized in that in addition to the slip arrangement ( 30 ) a starting element is provided. Method according to one of claims 8 or 9, characterized in that the slip arrangement ( 30 ) and / or the starting element as a friction clutch, or as a multi-plate clutch, or as a hydrodynamic coupling, or as a separating clutch in hybrid drives, or designed as a double clutch or a triple clutch, or is designed as a brake in conjunction with a planetary gear. Method according to one of the claims 3, characterized in that the ball ramp mechanism ( 70 ) as a threaded spindle mechanism ( 90 ) is executed. Method according to claim 11, characterized in that the threaded spindle mechanism ( 90 ) in direct engagement with the slip assembly ( 30 ) stands. Method according to one of claims 11 to 12, characterized in that the threaded spindle mechanism ( 90 ) is adapted to the slip arrangement ( 30 ) to provide a modulation range of 23 to 50 Hz or a range of 33 to 66 Hz or a range of 50 to 100 Hz. Method according to one of claims 11 to 13, characterized in that the slip arrangement ( 30 ) as a starting element ( 60 ) is used. Method according to one of claims 11 to 13, characterized in that in addition to the slip arrangement ( 30 ) a starting element is provided. Method according to one of claims 14 or 15, characterized in that the slip arrangement ( 30 ) and / or the starting element as a friction clutch, or as a multi-plate clutch, or as a hydrodynamic coupling, or as a separating clutch in hybrid drives, or designed as a double clutch or a triple clutch, or is designed as a brake in conjunction with a planetary gear. Method according to one of claims 1 to 16, characterized in that the axis of rotation (A) and the axis of rotation (B) extend coaxially or that the axis of rotation (A) and the axis of rotation (B) are offset.

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