Method for avoiding safety-critical activation of a clutch in a hybrid module of a drivetrain of a motor vehicle

Patent metadata

Field	Value
Publication number	US-9920797-B2
Application number	US-201415024533-A
Country	US
Kind code	B2
Filing date	Sep 23, 2014
Priority date	Sep 25, 2013
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

The invention relates to a method for avoiding safety-critical activation of a clutch in a hybrid module of a drivetrain of a motor vehicle, wherein the hybrid module is effective between the internal combustion engine and the transmission and has an electric drive, the clutch and a freewheel, and the clutch is used to start the internal combustion engine by transmitting a torque, supplied by the electric drive or the drivetrain, by a frictionally locking connection to the electric drive or the drivetrain, or for disconnecting the internal combustion engine from the drivetrain for purely electric driving. In a method for avoiding safety-critical activation of a clutch in a hybrid module in which safety-critical driving situations are reliably prevented, a critical interference torque of the clutch is set as a function of ambient conditions of the motor vehicle and/or peripheral conditions of the vehicle, in order to set a safety distance to be maintained by the open clutch.

First claim

The invention claimed is:

1. A method for avoiding safety-critical activation of a clutch in a hybrid module of a drivetrain of a motor vehicle, wherein the hybrid module is effective between the internal combustion engine and a transmission and has an electric drive, a clutch, and a freewheel, the clutch and the freewheel being arranged between the internal combustion engine and the electric drive, the method comprising:
using the clutch to start the internal combustion engine by transmitting a torque, supplied by the electric drive or the drivetrain, by a frictionally locking connection to the electric drive or the drivetrain or to decouple the internal combustion engine from the drivetrain for purely electric travel, and
via a control device, setting a critical interference torque (M crit ) associated with a closing of the clutch in order to set a safety distance which is to be maintained when the clutch is opened as a function of at least one of ambient conditions of the motor vehicle or peripheral conditions of the motor vehicle.

2. The method as claimed in claim 1 , further comprising determining the critical interference torque (M crit ) as a function of a coefficient of friction (μ) of wheels of the motor vehicle.

3. The method as claimed in claim 2 , wherein the coefficient of friction (μ) is formed as a constant for a predefined range of an external temperature of the motor vehicle.

4. The method as claimed in claim 1 , further comprising determining the critical interference torque (M crit ) as a function of a lateral acceleration of the motor vehicle.

5. The method as claimed in claim 1 , further comprising when the critical interference torque (M crit ) is exceeded by a predefined torque, initiating vehicle movement dynamic adjustments for increasing the critical interference torque (M crit ) in order to ensure safety of the motor vehicle.

6. The method as claimed in claim 1 , wherein information about at least one of the ambient conditions or the peripheral conditions of the motor vehicle is made available by the control device via a communication line of the motor vehicle.

7. The method as claimed in claim 1 , wherein the safety distance of the open clutch is set based on a clutch characteristic curve taking into account information about the at least one of the ambient conditions or the peripheral conditions of the motor vehicle.

8. A method for avoiding safety-critical activation of a clutch in a hybrid module of a drivetrain of a motor vehicle,
the drivetrain comprising an internal combustion engine, a hybrid module, a transmission, and a control device,
the hybrid module is effective between the internal combustion engine and the transmission, and
the hybrid module comprising:
(1) an electric drive;
(2) a clutch arranged to (a) frictionally lock the internal combustion engine, the electric drive, and the transmission to start the internal combustion engine; and (b) decouple the internal combustion engine from the electric drive and the transmission for purely electric travel; and,
(3) a freewheel arranged to transmit torque from the internal combustion engine to the transmission;

the method comprising:
providing the drivetrain; and
via the control device, setting a critical interference torque (M crit ) associated with a closing of the clutch in order to set a safety distance which is to be maintained when the clutch is opened as a function of at least one of ambient conditions of the motor vehicle or peripheral conditions of the motor vehicle.

Assignees

• Schaeffler Technologies Ag

Inventors

• Kuss Volker
• Dilzer Martin

Classifications

• B60W10/02 Primary

  including control of driveline clutches · CPC title

• Y10S903/914

  Actuated, e.g. engaged or disengaged by electrical, hydraulic or mechanical means · CPC title

• B60Y2200/92

  Hybrid vehicles · CPC title

• F16D2500/5029

  Reducing drag torque · CPC title

• B60W2710/027

  Clutch torque · CPC title