METHOD FOR CONTROLLING A SEPARATING CLUTCH IN A HYBRID DRIVE TRAIN, AND DRIVE TRAIN

• US 20140128218A1
• Filed: 01/09/2014
• Published: 05/08/2014
• Est. Priority Date: 07/11/2011
• Status: Active Grant

• Current Assignee: Schaeffler Technologies AG & Co.KG (INA-Holding Schaeffler GmbH & Co. KG)
• Original Assignee: Schaeffler Technologies AG & Co.KG (INA-Holding Schaeffler GmbH & Co. KG)
• Inventors: Ruder, Willi, Dilzer, Martin
• Granted Patent: US 9,108,637 B2
• Time in Patent Office: Days
• US Class Current: 477/5
• CPC Class Codes: B60K 2006/268 Electric drive motor starts the engine, i.e. used as starter motor
• CPC Class Codes: B60K 2006/4825 Electric machine connected or connectable to gearbox input shaft
• CPC Class Codes: B60K 6/383 One-way clutches or freewheel devices
• CPC Class Codes: B60K 6/387 Actuated clutches, i.e. clutches engaged or disengaged by electric, hydraulic or mechanical actuating means
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/40 Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• 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 2710/027 Clutch torque
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 30/186 excessive wear or burn out of friction elements, e.g. clutches
• CPC Class Codes: B60W 30/1884 Avoiding stall or overspeed of the engine
• CPC Class Codes: F16D 2500/1066 Hybrid
• CPC Class Codes: F16D 2500/50224 Drive-off
• CPC Class Codes: F16D 2500/50661 Limit transmission input torque
• CPC Class Codes: F16D 2500/5085 Coasting
• CPC Class Codes: F16D 48/08 : Regulating clutch take-up on starting
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y10S 903/902 : Prime movers comprising electrical and internal combustion motors

Abstract

A hybrid drivetrain and method for controlling a friction clutch of a hybrid drivetrain of a motor vehicle having a combustion engine which is coupled by means of a freewheel to a transmission input shaft of a transmission to transmit the engine torque, and having an electric machine which starts the combustion engine and/or propels the motor vehicle, which friction clutch transmits to the combustion engine a summed torque formed of a starting torque for starting the combustion engine by means of the electric machine and a drag torque which acts on the combustion engine when the drivetrain is in drag mode. To be able to operate the friction clutch reliably and to avoid over-dimensioning of the friction clutch as a result of high summed torques, a torque present at the friction clutch is limited to a predefined transmission torque which can be transmitted via the friction clutch.

Claims

1. A method for controlling a friction clutch of a hybrid drivetrain of a motor vehicle having a combustion engine, which is coupled by means of a freewheel to a transmission input shaft of a transmission to transmit the engine torque, the method comprising the following steps:

starting the combustion engine and/or propelling the motor vehicle via an electric machine;

transmitting a summed torque formed of a starting torque from the friction clutch to the combustion engine for starting the combustion engine by means of the electric machine; and

,

acting on the combustion engine via a drag torque when the drivetrain is in drag mode, wherein the summed torque present at the friction clutch is limited to a predefined transmission torque which can be transmitted via the friction clutch.

2. A method as recited in claim 1, wherein the friction clutch is operated by means of a self-arresting clutch actuator.

5. A drivetrain for carrying out the method as recited in claim 1, comprising:

a combustion engine which is coupled by means of a freewheel to a transmission input shaft of a transmission to transmit the engine torque;

an electric machine which starts the combustion engine and/or propels the motor vehicle;

a friction clutch at which a summed torque formed of a starting torque for starting the combustion engine by means of the electric machine; and

,

a drag torque which acts on the combustion engine when the drivetrain is in drag mode is present, wherein the friction clutch is designed for a predefined transmission torque which limits the summed torque while maintaining a safety margin.

3. The method as recited in Claim I, wherein to transmit the transmission torque an actuator travel is assigned to the latter by means of a characteristic curve.

4. The method as recited in claim 3, wherein the characteristic curve is adapted as needed.