Method and device for referencing an incremental travel sensor in an electronically controlled actuation device of a clutch

1. A method for referencing an incremental travel sensor in an electronically controlled actuation device of a clutch in the drive train of a traveling vehicle, the actuation device containing a memory in which a characteristic curve is stored that indicates the clutch torque as a function of the position of an actuation element, the method comprising the following steps:

determining whether the clutch is slipping beyond a given threshold; if so

determining the current clutch torque; and,

determining the current position of the actuation element based on the current clutch torque and the characteristic curve, wherein the current clutch torque is determined according to the following equation:

M K =|M M −J× {dot over (ω)} |

wherein M K =Clutch torque

M M =Engine torque

J=Moment of inertia of the engine; and,

{dot over (ω)} =speed change of the engine over time.

2. The method as described in claim 1 , wherein the slip is calculated via a comparison of an engine speed on the clutch input side with a transmission input speed on the clutch output side.

3. The method as described in claim 2 , wherein the transmission input speed may be calculated from the instantaneous transmission ratio, the axle ratio and the instantaneous vehicle speed.

4. The method as described in claim 1 , wherein the slip is calculated via a comparison of an engine speed on the clutch input side with a transmission input speed on the clutch output side.

5. The method as described in claim 4 , wherein the transmission input speed may be calculated from the instantaneous transmission ratio, the axle ratio and the instantaneous vehicle speed.

6. The method as described in claim 1 , wherein, after calculation of the current clutch torque, the current reference clutch torque is set to the current clutch torque.

7. The method as described in claim 1 , wherein, after calculation of the current clutch torque, the current reference clutch torque is set to the current clutch torque.

8. The method as described in claim 1 , wherein a current gear is stored in an EEPROM of the actuation device after the gear is changed.

9. The method as described in claim 8 , wherein before the disengagement of an old gear begins an additional signal is set to “no gear” and is set to “gear” after engagement of a new gear.

10. The method as described in claim 1 , the method being carried out for the clutches of a parallel shift transmission.

11. A method for referencing an incremental travel sensor in an electronically controlled actuation device of a clutch in the drive train of a traveling vehicle that comprises the following steps:

determining whether the clutch is slipping beyond a given threshold; if not

determining whether a gear is engaged; if so,

completely engaging the clutch until the actuation device reaches an engagement reference limit stop.

12. The method as described in claim 11 , wherein a below-threshold slipping state is produced by reducing the engine torque.

13. A method for referencing an incremental travel sensor in an electronically controlled actuation device of a clutch in the drive train of a traveling vehicle comprising the following steps:

determining whether the clutch is slipping beyond a given threshold; if not,

determining whether a gear is engaged; if not,

completely disengaging or engaging the clutch until the actuation device reaches an engagement reference limit stop.

14. A method for referencing an incremental travel sensor in an electronically controlled actuation device of a clutch and at least one additional incremental travel sensor in an electronically controlled actuation device of a transmission in a vehicle drive train after a reset, especially an undervoltage reset, comprising the following steps:

completely disengaging the clutch and referencing of the incremental travel sensor assigned to the clutch actuation device in the fully disengaged position of the clutch;

maintaining the fully disengaged position of the clutch and referencing of the incremental travel sensor(s) assigned to the transmission actuation device;

shifting of the transmission into neutral; and,

completely engaging the clutch and referencing of the incremental travel sensor assigned to the clutch actuation device in the fully engaged position of the clutch.

15. A device for referencing an incremental sensor ( 23 ) in an electronically controlled actuation device ( 10 , 24 ) of a clutch ( 22 ) in the drive train of a vehicle, the actuation device including a microprocessor having a memorizing device in which is stored a characteristic curve that specifies the clutch torque as a function of the position of an actuation element ( 20 ) and to which the incremental sensor, other sensors and at least one actuator ( 10 ) of the actuator device are connected, programs being stored in the memorizing device in such a manner that the device carries out a method for referencing said incremental travel sensor in said electronically controlled actuation device of said clutch in the drive train of the traveling vehicle, the actuation device memorization device storing a characteristic curve that indicates the clutch torque as a function of the position of said actuation element, the method comprising the following steps:

determining whether the clutch is slipping beyond a given threshold; if so

determining the current clutch torque; and,

determining the current position of the actuation element based on the current clutch torque and the characteristic curve, wherein the current clutch torque is determined according to the following equation:

M K =|M M −J× ω |

wherein M K =Clutch torque

M M =Engine torque

J=Moment of inertia of the engine; and,

ω =speed change of the engine over time.

16. A device for referencing an incremental sensor ( 23 ) in an electronically controlled actuation device ( 10 , 24 ) of a clutch ( 22 ) in the drive train of a vehicle, the actuation device including a microprocessor having a memorizing device in which is stored a characteristic curve that specifies the clutch torque as a function of the position of an actuation element ( 20 ) and to which the incremental sensor, other sensors and at least one actuator ( 10 ) of the actuator device are connected, programs being stored in the memorizing device in such a manner that the device carries out a method for referencing said incremental travel sensor in said electronically controlled actuation device of said clutch in the drive train of said traveling vehicle that comprises the following steps:

determining whether the clutch is slipping beyond a given threshold; if not

determining whether a gear is engaged; if so,

completely engaging the clutch until the actuation device reaches an engagement reference limit stop.

17. A device for referencing an incremental sensor ( 23 ) in an electronically controlled actuation device ( 10 , 24 ) of a clutch ( 22 ) in the drive train of a vehicle, the actuation device including a microprocessor having a memorizing device in which is stored a characteristic curve that specifies the clutch torque as a function of the position of an actuation element ( 20 ) and to which the incremental sensor, other sensors and at least one actuator ( 10 ) of the actuator device are connected, programs being stored in the memorizing device in such a manner that the device carries out a method for referencing said incremental travel sensor in said electronically controlled actuation device of said clutch in the drive train of said traveling vehicle comprising the following steps:

determining whether the clutch is slipping beyond a given threshold; if not,

determining whether a gear is engaged; if not,

completely disengaging or engaging the clutch until the actuation device reaches an engagement reference limit stop.

18. A device for referencing an incremental sensor ( 23 ) in an electronically controlled actuation device ( 10 , 24 ) of a clutch ( 22 ) in the drive train of a vehicle, the actuation device including a microprocessor having a memorizing device in which is stored a characteristic curve that specifies the clutch torque as a function of the position of an actuation element ( 20 ) and to which the incremental sensor, other sensors and at least one actuator ( 10 ) of the actuator device are connected, programs being stored in the memorizing device in such a manner that the device carries out a method for referencing said incremental travel sensor in said electronically controlled actuation device of said clutch and at least one additional incremental travel sensor in said electronically controlled actuation device of said transmission in said vehicle drive train after a reset, especially an undervoltage reset, said method comprising the following steps:

completely disengaging the clutch and referencing of the incremental travel sensor assigned to the clutch actuation device in the fully disengaged position of the clutch;

maintaining the fully disengaged position of the clutch and referencing of the incremental travel sensor(s) assigned to the transmission actuation device;

shifting of the transmission into neutral; and,

completely engaging the clutch and referencing of the incremental travel sensor assigned to the clutch actuation device in the fully engaged position of the clutch.