Method for operating a clutch

Patent metadata

Field	Value
Publication number	US-10634199-B2
Application number	US-201615758003-A
Country	US
Kind code	B2
Filing date	Sep 30, 2016
Priority date	Sep 30, 2015
Publication date	Apr 28, 2020
Grant date	Apr 28, 2020

Abstract

Operating a clutch assembly of a vehicle drive train, the clutch assembly comprising a clutch with a clutch component that exchanges heat at least indirectly with a medium which is conducted at least partially in the clutch, comprises at least: a) determining an operating point parameter which is representative of a current operating state of the clutch; b) determining a first thermal property parameter of the medium, as a function of the determined operating point parameter; c) determining a second thermal property parameter of the at least one clutch component; d) calculating a component temperature of the at least one clutch component as a function of at least the following three values: a further component temperature of a further clutch component, the first thermal property parameter, and the second thermal property parameter; and e) adapting activation of the clutch as a function of the calculated component temperature.

First claim

The invention claimed is:

1. A method for operating a clutch assembly of a drive train of a vehicle, wherein the clutch assembly includes a clutch with at least one clutch component that exchanges heat at least indirectly with a medium which is conducted at least partially in the clutch, wherein the method comprises at least the following iteratively occurring steps:
a) determining an operating point parameter which is representative of a current operating state of the clutch;
b) determining a first thermal property parameter of the medium, as a function of the determined operating point parameter;
c) determining a second thermal property parameter of the at least one clutch component;
d) calculating a component temperature of the at least one clutch component as a function of at least the following three values: a further component temperature of a further clutch component, the first thermal property parameter, and the second thermal property parameter; and
e) adapting activation of the clutch as a function of the calculated component temperature.

2. The method of claim 1 , further comprising a step D) executed before step e), the step D) including:
D) calculating a medium temperature of the medium as a function of at least the following two values: the further component temperature of the further clutch component and the first thermal property parameter.

3. The method of claim 1 , wherein the operating point parameter includes one or more of:
a circumferential speed of a clutch disk;
a relative circumferential speed of the clutch disk, in relation to another clutch disk;
a change in a circumferential speed of the clutch disk;
a rotational speed of an input shaft or of an output shaft of the clutch;
a difference in rotational speed between the input shaft and the output shaft of the clutch;
a clutch pressure or contact pressure force acting between clutch disks;
a clutch torque;
a sump temperature; and
a volume flow of the medium through the clutch.

4. The method of claim 1 , wherein the first thermal property parameter includes one or more of:
a fill volume of the medium in the clutch;
a volume flow of the medium through the clutch;
a wetting of a clutch disk with the medium;
a viscosity of the medium in the clutch;
a thermal capacity of the medium in the clutch; and
a coefficient of heat transfer of the medium to the at least one clutch component.

5. The method of claim 1 , wherein the second thermal property parameter includes one or more of:
a thermal mass of the at least one clutch component;
a thermal capacity of the at least one clutch component;
a coefficient of heat transfer between the at least one clutch component and the medium, wherein the coefficient of heat transfer is calculated as a function of the operating point parameter; and
a coefficient of heat transfer to the further clutch component.

6. The method of claim 1 , wherein the at least one clutch component is at least one of:
a clutch disk;
a disk carrier;
a sump; and
a clutch housing.

7. The method of claim 1 , wherein in step d) the calculation of the component temperature is further carried out as a function of at least one prior component temperature determined in a preceding iteration, the at least one prior component temperature relating to at least one of a same and a different component as the component temperature.

8. The method of claim 2 , wherein, before the steps d) and D), a sump temperature of a sump of the clutch is determined, and the sump temperature is additionally taken into account in steps d) and D) to calculate a disk carrier temperature or the medium temperature.

9. An electronic control unit for a vehicle having a clutch assembly for variably distributing torque to different axles of the vehicle, wherein the clutch assembly includes a clutch with at least one clutch component, wherein the electronic control unit which is configured to carry out iteratively at least the following steps:
a) determining an operating point parameter which is representative of a current operating state of the clutch;
b) determining a first thermal property parameter of the medium, as a function of the determined operating point parameter;
c) determining a second thermal property parameter of the at least one clutch component;
d) calculating a component temperature of the at least one clutch component as a function of at least the following three values: a further component temperature of a further clutch component, the first thermal property parameter, and the second thermal property parameter; and
e) adapting activation of the clutch as a function of the calculated component temperature.

10. The electronic control unit of claim 9 , further configured to carry out a step D) executed before step e), the step D) including:
D) calculating a medium temperature of the medium as a function of at least the following two values: the further component temperature of the further clutch component and the first thermal property parameter.

11. The electronic control unit of claim 9 , wherein the operating point parameter includes one or more of:
a circumferential speed of a clutch disk;
a relative circumferential speed of the clutch disk, in relation to another clutch disk;
a change in a circumferential speed of the clutch disk;
a rotational speed of an input shaft or of an output shaft of the clutch;
a difference in rotational speed between the input shaft and the output shaft of the clutch;
a clutch pressure or contact pressure force acting between clutch disks;
a clutch torque;
a sump temperature; and
a volume flow of the medium through the clutch.

12. The electronic control unit of claim 9 , wherein the first thermal property parameter includes one or more of:
a fill volume of the medium in the clutch;
a volume flow of the medium through the clutch;
a wetting of a clutch disk with the medium;
a viscosity of the medium in the clutch;
a thermal capacity of the medium in the clutch; and
a coefficient of heat transfer of the medium to the at least one clutch component.

13. The electronic control unit of claim 9 , wherein the second thermal property parameter includes one or more of:
a thermal mass of the at least one clutch component;
a thermal capacity of the at least one clutch component;
a coefficient of heat transfer between the at least one clutch component and the medium, wherein the coefficient of heat transfer is calculated as a function of the operating point parameter; and
a coefficient of heat transfer to the further clutch component.

14. The electronic control unit of claim 9 , wherein the at least one clutch component is at least one of:
a clutch disk;
a disk carrier;
a sump; and
a clutch housing.

15. The electronic control unit of claim 9 , further configured so that, in step d), the calculation of the component temperature is further carried out as a function of at least one prior component temperature determined in a preceding iteration, the at least one prior component temperature relating to at least one of a same and a different component as the component temperature.

16. The electronic control unit of claim 10 , further configured so that, before the steps d) and D), a sump temperature of a sump of the clutch is determined, and the sump temperature is additionally taken into account in steps d) and D) to calculate a disk carrier temperature or the medium temperature.

17. A vehicle having a clutch assembly for variably distributing torque to different axles of the vehicle, wherein the clutch assembly i

Assignees

• Gkn Automotive Ltd

Inventors

• Ruiters Volker Rene

Classifications

• F16D2500/30415

  Speed of the input shaft · CPC title

• F16D2500/7082

  of the clutch · CPC title

• F16D2500/30406

  Clutch slip · CPC title

• F16D2500/3051

  Flow amount of cooling fluid · CPC title

• F16D2500/30405

  Estimated clutch temperature · CPC title