EP3698068A1

EP3698068A1 - Damping arrangement for dampening rotational irregularities in a drive train of a motor vehicle and method therefor

Info

Publication number: EP3698068A1
Application number: EP18778850.0A
Authority: EP
Inventors: Tobias DIECKHOFF; Mathias Kopp; Alfred Tareilus; Christofer EBERT
Original assignee: ZF Friedrichshafen AG
Current assignee: ZF Friedrichshafen AG
Priority date: 2017-10-19
Filing date: 2018-09-19
Publication date: 2020-08-26
Also published as: CN111247354A; DE102017218686A1; CN111247354B; US20200332839A1; WO2019076564A1

Abstract

The invention relates to a damping arrangement for dampening rotational irregularities in a drive train of a motor vehicle, comprising a slip arrangement for providing a slip between the input region and output region of a torque transmission arrangement, wherein the slip arrangement comprises a control device, which is designed to control the slip as a function of a measurement signal for a rotational irregularity, wherein the control device is designed to control the slip as a function of at least one parameter of a periodic vibration component of an alternating component of a speed proceeding from an average speed, wherein a sensor device is arranged which is connected to the control device, wherein the sensor device is designed to determine the average speed in the torque transmission path after the slip arrangement and wherein the sensor device is designed to determine a frequency of the alternating component in the torque transmission path before the slip arrangement.

Description

DAMPING ARRANGEMENT FOR DAMPING

ROTATIONAL LIKE IN A DRIVE TRAIN OF A MOTOR VEHICLE AND METHOD THEREFOR

The invention relates to a damping arrangement for damping rotational irregularities in a drive train of a motor vehicle, comprising a slip arrangement for providing a slip between the input area and the output area of a torque transmission arrangement, wherein the slip arrangement comprises a control device which is designed to control the slip in response to a measurement signal for a To regulate rotational irregularity.

The invention further relates to a method for damping rotational irregularities in a drive train of a motor vehicle, wherein a slip is provided by means of a slip arrangement between the input area and the output area of a torque transmission arrangement, and wherein the slip is regulated by means of a control device as a function of a measurement signal for rotational nonuniformity.

Although applicable to any motor vehicle, the present invention will be described with reference to motor vehicles in the form of passenger cars with internal combustion engines.

To increase the efficiency or fuel economy of passenger cars with internal combustion engines, a variety of solutions have become known, for example engines with cylinder deactivation, start / stop systems and / or different hybridization stages. However, this leads in the car drive trains to increased rotational nonuniformity or increasing excitations, in particular in the low speed range, for example, from idle speed to about 1400 1 / min.

In order to dampen such rotational irregularities, in addition to spring-mass arrangements, eg two-mass flywheel ZMS, speed-adaptive absorbers DAT have become known. Furthermore, it has become known in drive trains with wet-running starting element, via slip in the starting element a reduction to achieve the torque fluctuations of the internal combustion engine. In this case, a predetermined average slip speed is set. In addition, it has become known from DE 10 2008 009 135 A1 to reduce a rotational speed difference of a resonance speed width applied to a friction clutch during startup by corresponding activation of the friction clutch.

A method for determining a slip of a clutch is known from WO

99/23392 A1 become known.

From US 2004/0260444 A1 a damping arrangement is further known, comprising a clutch and a sensor arrangement, wherein the clutch is actuated by means of signals of the sensor arrangement in order to avoid vibrations in the drive train. Here, the speed of an input shaft and the speed of a wheel of the motor vehicle is used as a parameter for the control of the clutch for damping vibrations.

From WO 2004/018890 A2 a method for isolating torsional vibrations has become known. Here, the slip between a drive and output element of a clutch is controlled in response to vibration signals, which are transmitted by means of a vibration sensor to a corresponding control device.

A disadvantage of the already known methods is that they are inflexible and therefore provide an insufficient decoupling or damping of rotational irregularities. In addition, these require heavy and therefore more expensive components for a pre-decoupling for rotational irregularities.

An object of the present invention is therefore to provide a damping arrangement and a method for damping rotational irregularities, which achieve better decoupling, in particular with the same friction losses.

Another object of the present invention is to provide a damper assembly and method for damping rotational nonuniformities provide a substantially same decoupling level as already known methods or systems, wherein lighter and cheaper components can be used for the pre-decoupling.

The present invention solves the objects of a damping arrangement for damping rotational irregularities in a drive train of a motor vehicle, comprising a slip arrangement for providing slip between the input area and the output area of a torque transmission arrangement, the slip arrangement comprising a control device which is designed to control the slip in response to an input signal for regulating a rotational irregularity, characterized in that the control device is designed to regulate the slip as a function of at least one parameter of a periodic oscillation component of an alternating component of a rotational speed starting from an average rotational speed, and that a sensor device is arranged which is connected to the regulating device is, wherein the sensor device is designed to determine the average speed in the torque transmission path after the slip arrangement and wherein the sensor device is formed a e Determine the frequency of the alternating component in the torque transmission path before the slip arrangement.

The present invention solves the objects in a method for damping rotational irregularities in a drive train of a motor vehicle, wherein slip is provided by means of a slip arrangement between the input area and the output area of a torque transmission arrangement, and by means of a control device the slip is regulated as a function of a measurement signal for rotational nonuniformity in that, by means of the control device, the slip is controlled as a function of at least one parameter of a periodic oscillation component of an alternating component of a rotational speed starting from an average rotational speed and that the mean rotational speed in the torque transmission path is determined by the slip arrangement by means of a sensor device which is connected to the slip arrangement is determined and a frequency of the alternating component in the torque transmission path before the slip arrangement. One of the advantages achieved with this is that, in particular after the starting process, an advantageous torsional vibration reduction is effected. A further advantage is that it increases the efficiency, since the control device actuates the slip arrangement in accordance with the actual decoupling requirement. In addition, it increases flexibility, since depending on the driving situation, it adjusts the damping accordingly to the rotational irregularities, thus increasing the energy efficiency in the drive train and at the same time improving the damping of rotational irregularities. A further advantage is that during operation, a control of the rotational irregularities takes place without a control taking place on the basis of stored parameters, maps or the like.

In other words, function-relevant parameters or parameters in the advantageous range of the torque transmission arrangement are tapped for the damping of rotational irregularities, which then serve as input variables for the control of the slip arrangement.

Further features, advantages and further embodiments of the invention are described below or become apparent:

According to an advantageous development, the sensor device is designed to determine an amplitude of the rotational irregularities as a parameter in the torque transmission path after the slip arrangement. In other words, the remaining rotational irregularities on the secondary side of the slip arrangement are thus used as a reference variable. The advantage of this is that it enables a particularly reliable determination of the rotational irregularities.

According to a further advantageous development, the sensor device has a position sensor for a shaft of a drive of the motor vehicle, in particular a crankshaft position sensor. The advantage of this is that the engine speed or the ignition frequency of the engine before the slip arrangement can be determined particularly accurately. According to a further advantageous development, a rotational nonuniformity decoupling device, in particular comprising at least one rotationally adaptive absorber, is arranged in front of the slip arrangement, and the sensor device comprises a primary rotational speed sensor which is arranged in the torque transmission path downstream of the rotational nonuniformity decoupling device and upstream of the slip arrangement. At this point in the torque transmission path, a large part of the rotational irregularities have already been filtered out by the rotational nonuniformity pre-decoupling device, so that a more exact detection of the rotational speed is possible directly at the location relevant to the function at the input area of the slip arrangement.

According to a further advantageous development, the sensor device for determining the amplitude of the rotational irregularities as a parameter comprises a secondary speed sensor and / or a secondary acceleration sensor, which in the

Torque transmission path is arranged after the slip arrangement. Advantage thereof is that so that the remaining rotational nonuniformity on the secondary side of the slip arrangement can be detected in a simple manner. This is particularly advantageous detectable via a speed sensor, which is arranged to determine the slip speed anyway.

According to a further advantageous development, a transmission is arranged in the torque transmission path after the slip arrangement and the sensor device is designed to determine the amplitude of the rotational irregularities in the torque transmission path to the transmission. This allows a particularly reliable determination of the amplitude of the rotational irregularities, since usually there is no vibration node at the output of the transmission, so that a reliable control of the slip for damping rotational irregularities is made possible.

According to a further advantageous development, at least one of the sensors, in particular all the sensors, is connected directly to the slip arrangement, in particular its control device. This allows a particularly rapid control of the slip through the slip arrangement, since thus real-time requirements of the signal Processing can be accommodated. Delays via a bus system are thus avoided.

According to a further advantageous embodiment, the control device comprises a memory which comprises start values for the control of the slip arrangement. Thus, the settling time, for example, for recording the amplitude can be shortened in an advantageous manner, when the control device starts its operation, for example when starting the motor vehicle.

According to a further advantageous embodiment, the control device comprises a memory which contains one or more values representing a predetermined decoupling quality and wherein the control device is designed to regulate an amplitude of the slip until the predetermined decoupling quality is reached. In this way, the efficiency is increased because the control device increases the amplitude of the modulation torque of the alternating component only until the desired decoupling quality is achieved.

According to a further advantageous development, the slip arrangement comprises a clutch for providing an average slip, and the control device is designed to provide a mean slip as a function of at least one of the characteristics. The advantage of this is that a slip control by means of a clutch is made possible in a simple and reliable manner.

According to an advantageous development of the method, vibration nodes of the periodic vibration component in the torque transmission path are determined and characteristic quantities are determined by means of the sensor device outside the determined vibration node. Thus, a particularly reliable and stable control is possible: the arrangement of a sensor in a node would cause the characteristics for the control with a too low or no amplitude are detected or it is even possible that the vibration in the Near a vibration node has a phase opposite to the actually calming vibration of rotational irregularities. As a result, larger amplitudes could be set as necessary, for example, and including the regulation of slip to dampen rotational irregularities become unstable.

According to a further advantageous embodiment of the method, the average slip is increased by the slip arrangement when a predetermined maximum of an amplitude of the alternating component is reached. In this way, the decoupling can be further improved, although the alternating component of the slip is already operated at the maximum amplitude.

According to a further advantageous refinement, a target decoupling quality for at least two different positions in the torque transmission path is predetermined, and the amplitude of the alternating component is increased only until the target decoupling quality has been attained and, in particular, this is then kept constant. This substantially increases the efficiency because the slip is not regulated beyond the desired decoupling quality.

Further important features and advantages of the invention will become apparent from the subclaims, from the drawings, and from associated figure description with reference to the drawings.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the present invention.

Preferred embodiments and embodiments of the invention are illustrated in the drawings and will be described in more detail in the following description, wherein like reference numerals refer to the same or similar or functionally identical components or elements.

Figure 1 shows a damping arrangement according to an embodiment of the present invention. Figure 2 shows steps of a method according to an embodiment of the present invention.

Figure 1 shows a damping arrangement according to an embodiment of the present invention.

FIG. 1 shows a damping arrangement 1 for a drive train of a motor vehicle. In this case, the drive train comprises a motor 10, which is connected to a rotation irregularity predistortion 9 in terms of torque. The Dreun- ungleichigkeitsvorentkopplung 9 is further downstream connected to a slip assembly 2, the slip assembly 2 on the output side with a gear 1 1 and the transmission 1 1 with other transmission elements - in the figure 1 referred to as the remaining drive train 12 - connected. Between engine 10 and rotational nonuniformity pre-decoupling 9, a crankshaft position sensor 20 is arranged. Between the rotational nonuniformity predistortion 9 and the

Slip arrangement 2, a rotational speed sensor 21 is arranged and between the slip arrangement 2 and the transmission 1 1, a further rotational speed sensor 22 is arranged. The rotational speed sensor 21 is thus arranged in the input region 3 of the slip arrangement 2, and the rotational speed sensor 22 is arranged in the output region 4 of the slip arrangement 2.

The slip assembly 2 comprises a control device 6 and a sensor device 7. The sensor device 7 is connected to the three sensors 20, 21 and 22 and further directly to the control device 6 for controlling the slip. Due to the real-time requirement of the signal processing, this is advantageous: If the sensors 20, 21, 22 have a direct data connection to the control device 6, the delays which are possible in the case of transmission via a bus system can be avoided.

The parameters for controlling the slip through the slip arrangement will now be described below. In the following, these are the frequency, more precisely the modulation frequency with which the slip is modulated, the average slip speed, the amplitude of the modulation of the slip and the phase position thereof. The modulation frequency for the slip to be set by the slip arrangement 2 is particularly directly proportional to the engine speed. In order to dampen the particularly comfort-relevant engine main order, the modulation frequency is adjusted exactly to the ignition frequency of the motor 10.

The speed of the motor 10 is preferably determined before the slip arrangement 2, since the speed behind the slip assembly 2 is already reduced by the slip speed. Since the slip speed is variable, so behind the slip assembly 2 no direct proportionality between the local speed and the ignition frequency is given more. The speed of the motor 10 or its ignition frequency can be determined at different positions in the torque transmission path 8 before the slip arrangement 2. It can be determined, for example, directly from the engine 10 by means of a crankshaft position sensor 20. Particularly advantageous is an arrangement of a speed sensor 21 in the torque transmission path 8 behind the DU pre-decoupling 9 and before the slip assembly 2. By the DU pre-decoupling 9, which may for example consist of an arrangement of springs and speed-adaptive Tilgern, the speed at this point is already freed from a large part of the rotational irregularities. This has the advantages that parts of the rotational speed sensor 21 are exposed to a lower mechanical load and that a more accurate detection of the rotational speed is possible directly at the location relevant to the function at the input area of the slip arrangement 2.

As a further parameter, the average slip speed is determined. To determine the slip speed, in addition to the rotational speed information for the primary side 3 of the slip arrangement 2, a rotational speed on the secondary side 4 of the slip arrangement 2 is necessary. The corresponding speed sensor 22 may, as already stated, be arranged in the torque transmission path 8 behind the slip arrangement 2. The difference between the two speed signals of the sensors 21 and 22 corresponds to the slip speed, wherein the gear-dependent gear ratio is still to be considered, should the measuring point not be between the slip assembly 2 and the transmission 1 1.

To determine the amplitude for the slip, the reference variable is the Bene rotational irregularity on the secondary side 4 of the slip assembly 2 determined. This can be detected via an acceleration sensor, but particularly advantageously via the previously described rotational speed sensor 22, which is required anyway for determining the slip rotational speed. The control device 6 iteratively increases or decreases the amplitude as a function of the resulting change in the rotational nonuniformity determined with this sensor 22. The arrangement of the sensor 22 can in principle take place at any point of the drive train in the torque transmission path 8 behind the slip arrangement 2. Depending on the powertrain, however, there are positions where so-called

Training vibration nodes. At these positions, only small vibration amplitudes occur at certain operating points, while higher amplitudes occur at other positions of the powertrain. The arrangement of the sensor 22 in such a node is unfavorable, because then the command variable for the control with too low - or with no amplitude - is detected or it is even possible that the vibration in the vicinity of a vibration node is an opposite phase has as the actually calming vibration. Then the controller 6 would set ever larger amplitudes and become unstable.

In the case of a stepped automatic transmission for a rear drive train of a motor vehicle with a DU Vorentkopplungseinrichtung 9, comprising a spring accumulator and a downstream this Schwingungstilger usually forms at the entrance of the transmission 1 1 at a certain speed, a vibration node. In that regard, it is advantageous to arrange the arranged on the secondary side of the slip assembly 2 speed sensor 22 at the output of the transmission 1 1.

The phase position of the modulation of the slip is preferably controlled together with the amplitude by means of the control device 6. The control device 6 adjusts, in particular thus in addition to the amplitude, and the phase position iteratively according to the change of the at least one characteristic.

Figure 2 shows steps of a method according to an embodiment of the present invention. FIG. 2 schematically shows a slip arrangement 2 with a control device 6 as well as corresponding steps for controlling the slip of both an average rotational speed of the slip and a slip modulation. As input variables are the primary speed in front of the slip arrangement 2 in the form of a signal S21 and the secondary speed behind the slip arrangement 2 in the form of the signal S22. These signals S21, S22 are used by a control algorithm 15b for the mode 2 slip designated here, as well as a control algorithm 15a for the mode 1 slip referred to here, as reference variables.

The Mode 1 control algorithm 15a supplies as a manipulated variable a mean pressure SW-MD or derived therefrom size, such as a corresponding position or actuation of a pressure control valve or the like, which at a certain transmittable torque and a mean slipping speed of the

Slip arrangement 2 leads. These can, as shown here, be recorded and converted by a separate control unit 13a for an actuator 14a, which activates the mode 1 slip.

The mode 2 control algorithm 15b supplies the manipulated variable SW-DM, the frequency which is determined from the signal of the primary-side sensor 21, and the amplitude and the phase position of the modulation of a size for actuation of a slip device, in particular in the form of a coupling, which from the Signal S22 of the secondary-side sensor 22 can be determined. These can, as shown here, by a separate control unit 13b for an actuator 14b, which activates the mode 2 slip, recorded and implemented.

In particular, when the activation of the mode 2 slip by the same actuator 14a, 14b as the activation of the mode 1 slip takes place, the division into two different control devices 13a, 13b omitted, so that all variables from the same controller 13a, 13b and a corresponding actuator 14a, 14b implemented.

Between the control algorithms 15a, 15b for the mode 1 and the mode 2 slip, a data exchange 16 can take place, for example, around the modulo lationsamplitude to use for precontrol of the average slip speed and to prevent adhesion between the primary and secondary side 3, 4 of the slip assembly 2, even at high amplitudes. If the mode-2 slip is already operated with the maximum amplitude which can be provided by the associated actuator 13b, it is thus also possible to raise the mean slip speed by means of the actuator 14a in order to further improve the decoupling.

It may be advantageous to provide the control means 6 with start values for phase and amplitude which reduce the settling time when it starts operating. In addition, a target decoupling quality for different operating points can be predefined via a parameter table. The controller 6 then only increases the amplitude of the slip modulating torque until the target decoupling performance is achieved, resulting in increased powertrain efficiency.

In summary, the invention has, inter alia, the advantage that the decoupling and the efficiency of the drive train is improved. In addition, the damping of rotational irregularities in the drive train of motor vehicles is made possible in a reliable and efficient manner. Another advantage is that a regulation is made according to the actual decoupling requirement.

Although the present invention has been described in terms of preferred embodiments, it is not limited thereto, but modifiable in a variety of ways.

REFERENCE CHARACTERS

1 damping arrangement

2 slip arrangement

3 entrance area

4 output range

5 torque transmission arrangement

6 control device

7 sensor device

8 torque transmission path

9 rotational nonuniformity predistortion

10 engine

1 1 gearbox

12 downstream powertrain

13a, b control unit

14a, b actor

15a, 15b control method

16 data exchange

20 position sensor

21 speed sensor

22 speed sensor

SW-DM setpoint pressure modulation

SW-MD setpoint mean pressure

S21, S22 speed signal

Claims

claims

1 . Damping arrangement (1) for damping rotational irregularities in a drive train of a motor vehicle,

full

a slip arrangement (2) for providing slippage between the input area (3) and the output area (4) of a torque transmission arrangement, the slip arrangement (2) comprising a control device (6) designed to control the slip in response to an input signal for rotational nonuniformity .

characterized in that

the control device (6) is designed to regulate the slip as a function of at least one parameter of a periodic oscillation component of an alternating component of a rotational speed starting from an average rotational speed, and in that a sensor device (7) is arranged which is connected to the regulating device (6), wherein the sensor device (7) is designed to determine the average rotational speed in the torque transmission path (8) after the slip arrangement (2) and wherein the sensor device (7) is designed to generate a frequency of the alternating component in the torque transmission path (8) before the slip arrangement (2). to investigate.

2. Damping device according to claim 1, characterized in that the sensor device (7) is designed to determine an amplitude of the rotational irregularities as a parameter in the torque transmission path (8) after the slip arrangement (2).

3. Damping arrangement according to one of claims 1 -2, characterized in that the sensor device (7) has a position sensor (20) for a shaft of a drive (10) of the motor vehicle, in particular a crankshaft position sensor.

4. Damping arrangement according to one of claims 1 -3, characterized in that a rotational nonuniformity pre-decoupling device (9), in particular comprising at least one speed-adaptive absorber, is arranged in front of the slip arrangement (2), and the sensor device (7) comprises a primary rotational speed sensor (21) which is arranged in the torque transmission path (8) downstream of the rotational nonuniformity decoupling device (9 ) and in front of the slip arrangement (2).

5. Damping arrangement according to claim 2, characterized in that the sensor device (7) for determining the amplitude of the rotational irregularities as characteristic comprises a secondary speed sensor (22) and / or a secondary acceleration sensor in the torque transmission path (8) after the slip arrangement ( 2) is arranged.

6. Damping arrangement according to one of claims 2 or 5, characterized in that

a transmission (1 1) in the torque transmission path (8) after the slip assembly (2) is arranged and the sensor device (7) is adapted to determine the amplitude of rotational irregularity in the torque transmission path (8) after the transmission (1 1).

7. Damping arrangement according to one of claims 1 -5, characterized in that at least one of the sensors (20, 21, 22), in particular all sensors directly to the slip assembly (2), in particular its control device (6) is connected.

8. Damping arrangement according to one of claims 1 -6, characterized in that the control device (6) comprises a memory which comprises start values for the control of the slip arrangement (2).

9. Damping arrangement according to one of claims 1-7, characterized in that the control device (6) comprises a memory containing one or more values representing a predetermined decoupling quality and wherein the control device (6) is formed, an amplitude of the slip until the predetermined decoupling quality has been achieved.

10. Damping arrangement according to one of claims 1-9, characterized in that the slip arrangement (2) comprises a clutch for providing an average slip and the control device (6) is adapted to provide a mean slip in response to at least one of the characteristics.

1 1. Method for damping rotational irregularities in a drive train of a motor vehicle,

wherein a slip is provided by means of a slip arrangement (2) between the input area (3) and output area (4) of a torque transmission arrangement (5), and wherein the slip is regulated by means of a control device (6) as a function of a measuring signal for rotational irregularity,

characterized in that by means of the control device (6) the slip is controlled as a function of at least one parameter of a periodic oscillation component of an alternating component of a rotational speed, starting from an average rotational speed, and

by means of a sensor device (7) which is connected to the slip arrangement (2), the average speed in the torque transmission path after the slip arrangement (2) is determined and a frequency of the alternating component in the torque transmission path before the slip arrangement (2) is determined.

12. The method according to claim 1 1, characterized in that vibration nodes of the periodic vibration component in the torque transmission path (8) are determined and characteristics by means of the sensor device (7) au ßerhalb the determined vibration nodes are determined.

13. The method according to any one of claims 1 1-12, characterized in that the average slip through the slip arrangement (2) is increased when a predetermined maximum of an amplitude of the alternating component is reached.

14. The method according to any one of claims 1 1 -13, characterized in that a target decoupling goodness for at least two different positions in the torque transmission path (8) is specified and that the amplitude of the alternating selanteils only increased so far until the target decoupling quality is achieved and in particular is then kept constant.