METHOD FOR REDUCING JUDDERING VIBRATIONS

• US 20050189192A1
• Filed: 03/11/2005
• Published: 09/01/2005
• Est. Priority Date: 09/12/2002
• Status: Active Grant

• Current Assignee: Schaeffler Technologies AG & Co.KG (INA-Holding Schaeffler GmbH & Co. KG)
• Original Assignee: LuK Lamellen und Kupplungsbau Beteiligungs KG (INA-Holding Schaeffler GmbH & Co. KG)
• Inventors: Serebrennikov, Boris
• Granted Patent: US 7,299,120 B2
• Time in Patent Office: Days
• US Class Current: 192/30.V
• CPC Class Codes: B60W 2510/1015 Input shaft speed, e.g. turbine speed
• CPC Class Codes: B60W 2710/022 Clutch actuator position
• CPC Class Codes: B60W 2710/025 Clutch slip, i.e. difference between input and output speeds
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 30/20 Reducing vibrations in the driveline
• CPC Class Codes: F16D 2500/10412 Transmission line of a vehicle
• CPC Class Codes: F16D 2500/1045 Friction clutch
• CPC Class Codes: F16D 2500/30402 Clutch friction coefficient
• CPC Class Codes: F16D 2500/30426 Speed of the output shaft
• CPC Class Codes: F16D 2500/30816 Speed of the input shaft
• CPC Class Codes: F16D 2500/3165 Using the moment of inertia of a component as input for the control
• CPC Class Codes: F16D 2500/50224 Drive-off
• CPC Class Codes: F16D 2500/50293 Reduction of vibrations
• CPC Class Codes: F16D 2500/7044 Output shaft torque
• CPC Class Codes: F16D 48/06 Control by electric or electronic means, e.g. of fluid pressure

Abstract

Disclosed is a method for reducing juddering vibrations in a motor vehicle drive train which can be loaded by means of a drive device such as an internal combustion engine and comprises a clutch device and a transmission device. Also disclosed is an electronic control device.

Claims

1. A method for reducing juddering vibrations in a motor vehicle drive train that is loadable by a drive device, such as an internal combustion engine, and has a clutch device as well as a transmission device, comprising the following steps:

determining whether juddering vibrations are present;

disposing a device in the drive train or coupling the device to the drive train;

assigning a rotary parameter, such as torque or speed, to a drive train component; and

, adjusting, and especially automatically adjusting, the device in order to counteract the juddering vibrations, where in response to the adjusting, the rotary parameter is modified and in response to modifying the rotary parameter, the juddering vibration is modified over time.

2. The method as described in claim 1 wherein the adjusting further comprises modulating the torque that is transmissible by the clutch device and/or the clutch control travel to counteract the juddering vibration.

3. The method as described in claim 2, wherein the adjusting further comprises sinusoidally modulating the torque that is transmissible by the clutch device and/or the clutch control travel.

4. The method as described in claim 2 wherein the juddering vibration comprises at least one predetermined time characteristic and the drive train comprises a component having at least one parameter;

and, said method further comprising;

calculating said at least one predetermined parameter of the time characteristic and/or calculating said at least one parameter of the drive train component, such as a transmission input speed.

6. The method as described in claim 4 further comprising:

calculating a first phase and/or amplitude and/or period of the modulation of the clutch control travel and/or of the transmissible clutch torque as a function of the transmission input speed.

7. The method as described in claim 4 further comprising:

measuring the transmission input speed.

8. The method as described in claim 7 wherein measuring the transmission input speed further comprises measuring the transmission input speed at set time intervals.

9. The method as described in claim 4 wherein the calculated transmission input speed comprises a first at least one local extremum, especially a first at least one local maximum;

and, the method further comprising;

calculating a second period and/or phase and/or amplitude as a function of the first at least one local extremum.

10. The method as described in claim 6 further comprising:

calculating a second period and/or phase and/or amplitude for the modulated torque that is transmissible by the clutch device and/or of the modulated clutch control travel as a function selected from the group consisting of the calculated period, the phase, the amplitude of the juddering vibration, and the transmission input speed.

11. The method as described in claim 4 wherein the juddering vibration comprises a parameter and the transmission input speed comprises a time characteristic;

and, the method further comprising;

determining the parameter and/or of the time characteristic via an estimate and/or measurement and/or calculation in a first step; and

determining the parameter in a second step as a function of the determination of the first step for the improvement and/or monitoring of the precision of the parameter calculated in the first step.

12. The method as described in claim 11 wherein the calculated transmission input speed comprises a second at least one local extremum and a time position and where the parameter comprises the second at least one local extremum or the timing position of the second at least one local extremum.

13. The method as described in claim 4 wherein the juddering vibration comprises a third at least one local extremum, especially a third at least one local maximum, with a first actual position;

and the method further comprising;

measuring or evaluating the transmission input speed to provide speed signals at timed intervals, the signals comprising a fourth at least one local extremum, especially a fourth at least one local maximum, with a second actual position;

calculating, in a first step, the timing position of the fourth at least one local extremum, in particular a local extremum in the time characteristic that last occurred; and

, calculating and/or further approximating, in a second step, the first and/or second actual position.

14. The method as described in claim 13 further comprising:

calculating the time interval or the time deviation between the fourth at least one local extremum and the first and/or second actual position.

15. The method as described in claim 8 further comprising:

calculating in a first step, a phase angle of the juddering vibration and/or the time characteristic of the transmission input speed, in particular, calculating a local extremum, especially a local maximum of the transmission input speed, where the transmission input speed signals are provided at timed intervals; and

, calculating in a second step, the deviation between the phase angle detected in the first step and the actual phase angle and/or the deviation of a local extremum calculated in the first step by the actual extremum.

16. The method as described in claim 15 wherein calculating the deviation further comprises considering that in the first step, speed signals set at timed intervals, and/or measuring accuracies were used that are made necessary via the speed measurement in the first step.

17. The method as described in claim 15, wherein a prescribed control or evaluation, especially a measured value evaluation, occurs once within a prescribed time window (T_int);

and, the method further comprising providing or considering a prescribed measured value or measure value pair of a prescribed parameter, such as a transmission input speed, for this time window and considering the provision or consideration of the prescribed value in the calculation of the deviation.

18. The method as described in claim 15, wherein calculating the deviation further comprises considering any increase of the transmission input speed that is essentially independent of the juddering vibration.

19. The method as described in claim 15 wherein calculating the deviation further comprises using a parameter selected from the group consisting of interrupt time T_int, interrupt time T_int being the duration of a time period in which an evaluation, especially a measured value evaluation of the angular speed of the transmission input shaft, occurs once and is provided for the one measured value or measured value pair;

median, the median indicating the focal point of predetermined measured value pairs, and in particular from assignments of the angular speed of the transmission input shaft to instants at which these angular speeds are present;

an instant (T_max) that is present if a local extremum, especially a local maximum, related to rotary or angular speed signals of the transmission input shaft provided at timed intervals, which was detected as required in a first step, is present or is assigned to it;

local extremum, especially a local maximum (ω

_max) that is related to rotary or angular speed signals of the transmission input shaft, which in some cases was detected in a first step;

amplitude of juddering vibration (A) and in particular last amplitude of the juddering vibration;

frequency of the juddering vibration (ω

_Grabbing)/(2*π

));

total (average) slope of the angular speed of the transmission input shaft (B); and

, angle between two teeth of a travel sensor (φ

_Pulse).

20. The method as described in claim 14 further comprising:

determining or approximating, via the calculated deviation, an actual local extremum, especially a maximum, of the angular speed of the transmission input shaft and/or determining or approximating the actual phase of the angular speed of the transmission input shaft that is moved, also in a vibratory manner, during the juddering.

21. The method as described in claim 15 further comprising:

modulating the reference clutch control travel and/or of the torque transmissible by the clutch transmission using the phase angle calculated in the first step, and in particular the phase angle of the angular speed of the transmission input shaft and/or the juddering vibration.

22. The method as described in claim 15 further comprising:

using the phase angle of the rotary speed and/or the angular speed of the transmission input shaft and/or of the juddering vibration that is at least approximated in a second step to the actual phase angle of this transmission input speed and/or of the juddering vibration; and

/or using the deviation for the modulation of the reference clutch control travel and/or of the torque transmissible by the clutch device.

23. The method as described in claim 14 further comprising:

changing the period of the modulation of the reference clutch control travel and/or of the torque transmissible by the clutch device, and in particular in order to at least further approximate the phase angle of this modulated reference clutch control travel and/or torque transmissible by the clutch device to the actual phase angle of the speed of the transmission input shaft, using the time deviation of the time position between an extremum calculated in a first step, especially a local maximum, of the transmission input speed and a value for a local extremum at least approximated in a second step to the time position of an actual extremum, especially a maximum.

24. The method as described in claim 23, wherein changing the period of the modulation further comprises changing the period of the modulation of the reference clutch control travel and/or of the torque transmissible by the clutch device in such a manner that the period is extended or shortened for a period by this deviation.

25. The method as described in claim 21, further comprising:

modulating the reference clutch control travel and/or the torque transmissible by the clutch device as a function of the detected local extremum, especially local maximum, and/or of its time position and/or of a calculated deviation in order to counteract the juddering vibrations.

27. The method as described in claim 1 further comprising:

determining whether there are juddering vibrations in a motor vehicle drive train;

changing the position of a device to counteract juddering vibrations, whereby the juddering vibrations are counteracted by the change in the position of the device in first time segments and the change in the position of the device is interrupted in second time segments so that the system may vibrate freely in these two time segments; and

, in response changing the position of this device, changing a rotary parameter of a drive train component.

41. The method as described in claim 1 further comprising:

determining whether juddering vibrations are present in a motor vehicle drive train;

disposing a clutch device in this drive train that can be operated in a slip mode; and

modulating the torque transmissible by the clutch device and/or of the clutch control travel to counteract the detected juddering vibrations, whereby the modulation is such that there is control of a modulated reference clutch torque, which is specified as the difference between the unmodulated clutch torque and a product, whereby this product, furthermore, has a first factor that is a function of the angular speed of a clutch plate and/or the angular speed of a transmission input shaft and/or the angular speed of a wheel of the motor vehicle and/or a ratio that is assigned to a gear which is shifted in a transmission device disposed in a drive train, and whereby, furthermore, this adjustment constant is a function of parameters of the vibrating drive train system and/or of parameters that describe or at least assist in describing the friction characteristic of the clutch device.

42. The method as described in claim 1 further comprising:

determining whether juddering vibrations are present in a motor vehicle drive train;

disposing a clutch device in this drive train that can be operated in a slip mode; and

, modulating the torque transmissible by the clutch device and/or the clutch control travel to counteract detected juddering vibrations, whereby the modulation is such that there is control of a modulated reference clutch torque, which is specified as the difference between the unmodulated clutch torque and a product, whereby this product, furthermore, has a first factor that is a function of the angular speed of a clutch plate and/or the angular speed of a transmission input shaft and/or the angular speed of a wheel of the motor vehicle and/or a ratio that is assigned to a gear which is shifted in a transmission device disposed in a drive train, and whereby, furthermore, this adjustment constant is a function of the reference clutch torque and/or of a nominal clutch torque that is calculated assuming a nominal friction value and/or is a function of a calculated slip.

43. The method as described in claim 41, wherein the adjustment constant is a function of a function that describes how the coefficient of friction of the clutch device changes via the slip of the clutch device, and/or a function of the time derivative of such a function.

44. The method as described in claim 41, wherein the adjustment constant is a function of period T of the juddering vibration.

45. The method as described in claim 41, wherein the adjustment constant is a function of the moment of inertia of a clutch plate and/or of the transmission input.

46. The method as described in claim 41, wherein the adjustment constant is a function of a nominal coefficient of friction of the clutch device.

47. The method as described in claim 41, wherein the adjustment constant is a function of a quotient of two amplitudes of the juddering vibration that follow one after the other in time sequence and in particular of the logarithm of such a quotient.

49. The method as described in claim 1 further comprising:

determining whether juddering vibrations are present in a motor vehicle drive train;

disposing a clutch device within the drive train that is operable in a slip mode; and

, modulating the torque transmissible by the clutch device and/or of the clutch control travel to counteract detected juddering vibrations, whereby this modulation is such that the modulation is carried out in different sections according to a different characteristic.

50. The method as described in claim 1 further comprising:

determining whether juddering vibrations are present in a motor vehicle drive train;

disposing a clutch device within the drive train that is operable in a slip mode; and

, modulating the torque transmissible by the clutch device and/or of the clutch control travel to counteract detected juddering vibrations, whereby this modulation is such that it is designed in a vibratory manner and has a first half wave (68, 82) and as required a second half wave (70, 84), whereby the amplitude (66, 86) of the first half wave is greater than the amplitude (88) of the second half wave 70, 84).

51. The method as described in claim 50 further comprising:

interrupting or terminating the modulation according to the second half wave (70, 84); and

calculating the phase of the juddering vibration, and in particular via at least one local extremum, such as a local maximum, of the juddering vibration and/or of the transmission input speed.

52. The method as described in claim 50, wherein the amplitude (88) of the second half wave (70, 84) is equal to “

zero”

.

53. The method as described in claim 51 further comprising:

interrupting or terminating the modulation according to the first half wave (68, 82); and

, calculating the phase of the juddering vibration, and in particular via at least one local extremum, such as a local maximum, of the juddering vibration and/or of the transmission input speed.

54. The method as described in one of claim 50, wherein the first half wave (68, 82) and/or the second half wave (70, 84) is a half wave (68, 70, 82, 84) of a sinusoidal vibration.

55. The method as described in claim 2 further comprising:

starting the modulation with a phase shift in relation to the juddering vibration.

56. The method as described in claim 55 further comprising:

detecting a local extremum, especially a local maximum, of the juddering vibration; and

, in response to the detecting, starting the modulation.

57. The method as described in claim 2 further comprising:

forming the modulation in such a manner that a tangent of the time characteristic of the modulation of the transmissible torque and/or of the clutch control travel at the beginning and/or at the end of a half wave (68, 70) runs essentially parallel to the time axis.

58. The method as described in claim 1 further comprising:

determining whether juddering vibrations are present in a motor vehicle drive train;

disposing a clutch device within the drive train that is operable in a slip mode; and

, modulating the torque transmissible by the clutch device and/or the clutch control travel to counteract detected juddering vibrations, whereby the modulation is such that the modulation is determined as a function of the juddering vibration and/or the parameters describing the juddering vibration and/or a function describing the juddering vibration and as a function of prescribed boundary conditions.

59. The method as described in claim 58 further comprising:

describing the juddering vibration especially as a function of the torsion angle of a predetermined drive train section.

60. The method as described in claim 58 further comprising:

prescribing the characteristic of the modulation as a function of variables; and

, prescribing these variables at least partially on the basis of the boundary conditions.

61. The method as described in claim 58 wherein a boundary condition comprises the torsion angle at the instant “

zero”

corresponding to the difference between the torsion angle that would be present in the given load scenario while disregarding the juddering vibration and the angle amplitude corresponds to the juddering vibration.

62. The method as described in claims 58 wherein a boundary condition comprises the time derivative of the torsion angle at the “

zero”

instant being equal to “

zero”

.

63. The method as described in claim 58, wherein a boundary condition comprises the torsion angle at the instant of the half period of the juddering vibration corresponding to the torsion angle that would be present in the given load scenario while disregarding the juddering vibration.

64. The method as described in claim 58, wherein a boundary condition comprises the time derivative of the torsion angle at the instant of the half period of the juddering vibration being equal to “

zero”

.

65. The method as described in claim 58, wherein the period of the modulation of the torque transmissible by the clutch device and/or of the clutch control travel corresponds to the half period of the juddering vibration.

66. The method as described in claim 58 further comprising:

modulating the torque transmissible by the clutch device and/or the clutch control travel by an amount corresponding to a function a*sin(ω

*t), a being a factor, ω

corresponding to 2*π

times the frequency of the modulation vibration and t being the time.

67. An electronic controller that comprises a memorizing device and at least one device for outputting and/or receiving signals, whereby a data processing program is stored in the memorizing device of this electronic controller, and whereby this data processing program is able to control a method according to one of the preceding claims.

5. The method as described in claim 5 further comprising:

calculating a first phase and/or amplitude and/or period of the juddering vibration as a function of the transmission input speed.

26. A method for reducing juddering vibrations in a motor vehicle drive train that is loadable by a drive device, such as an internal combustion engine, and has a clutch device as well as a transmission device, comprising the following steps:

determining whether juddering vibrations are present in a motor vehicle drive train;

changing the position of a device selected from the group consisting of the transmission device and the clutch device to counteract detected juddering vibrations, where the position change is prescribed according to a predetermined function, especially a time function, that has a ramp function; and

, in response to changing the position, changing a rotary parameter of a drive train component.

28. The method as described in claim 26 wherein the device is the clutch device;

and the method further comprising;

modulating the torque transmissible by the clutch device and/or the clutch control travel, especially a reference clutch control travel, in order to counteract the juddering vibrations.

29. The method as described in claim 28, wherein the ramp function has a section in which a ramp is run up from a starting value to a value and a section situated later in time in which a ramp is driven back down from this value to a final value and in particular to a final value that corresponds to the starting value.

30. The method as described in claim 29, wherein the ramp function has at least one first section in which a ramp is driven up from a starting value to a value and at least one second section subsequent to the first section in which the ramp function is held to this constant value, and at least one third section in turn succeeding the second in which the ramp function is driven down from the constant value to a final value, and in particular to a final value that corresponds to the starting value.

31. The method as described in claim 30, wherein the constant value is essentially equal to “

one”

.

32. The method as described in claim 31, wherein the starting value and the final value of the ramp function in each case equals “

zero”

.

33. The method as described in claim 32 further comprising:

specifying the modulated clutch control travel as a function of an adjustment factor and in particular as a function of an adjustment constant.

34. The method as described in claim 33 further comprising:

specifying the modulated clutch control travel as a function of an amplitude of the juddering vibrations and in particular as a function of the last amplitude found.

35. The method as described in claim 34 further comprising:

determining the modulated clutch control travel as a function of a sine function and in particular as a function of a sine function that depends on the frequency of the judder and/or of time and/or of a determined phase shift between juddering vibration and the characteristic of the travel modulation.

36. The method as described in claim 34 further comprising:

determining the modulated clutch control travel as a function of an amplitude of the juddering vibration and as a function of a sine function, the amplitude being updated at the zero crossing of the sine function and in particular as a function of the transmission input speed.

48. The method as described in claim 26 further comprising:

building up the ramp to its target value within approximately one period of the juddering vibration.

37. A method for reducing juddering vibrations in a motor vehicle drive train that is loadable by a drive device, such as an internal combustion engine, and has a clutch device as well as a transmission device, comprising the following steps:

detecting that juddering vibrations are present; and

, alternately changing the position of a device selected from the group consisting of the transmission device and the clutch device, especially clutch control travel modulation, in first time segments and the excluded change of this position in second time segments until it detecting that the amplitude of the juddering vibration is smaller than a prescribed shutoff threshold.

38. The method as described in claim 37, wherein the duration of the first time segments corresponds to between one and five judder periods, especially two to three judder periods.

39. The method as described in claim 37 further comprising:

specifying the modulated clutch control travel as a function of a phase shift between the juddering vibration and the characteristic of the actual travel modulation and/or as a function of a sine function that is a function of the phase shift; and

, updating a current phase shift in two time periods.

40. The method as described in claim 37 further comprising:

specifying the modulated clutch control travel as a function of a phase shift between the juddering vibration and the characteristic of the actual travel modulation and/or as a function of a sine function that is a function of this phase shift; and

, considering a current phase shift in first time periods for the clutch control travel modulation as a constant and in particular at least partially corresponding to a value that was calculated of a previous second period.