Method for the operation of a drive train

US8123657B2 · kind B2 · utility

Assignee

• ZF FRIEDRICHSHAFEN AG · DE

Inventors

• Christian Mittelberger · Ravensburg, DE
• Johannes Kaltenbach · Friedrichshafen, DE
• Stefan Blattner · Weingarten, DE

Key dates

• Filing date: Sep 16, 2008
• Grant date: Feb 28, 2012
• Expiry date: May 2, 2029

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/64
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A method of operating a drive train comprising a hybrid drive with a combustion engine and an electric motor; a transmission positioned between the hybrid drive and the output; and a clutch positioned between the combustion engine and the electric motor. When the electric motor exclusively drives the vehicle, the combustion engine can be started by engaging the clutch. At the time when the electric motor permanently or without traction force interruption is coupled to the output, and the rotational speed of the electric motor is greater than the starting rotational speed of the combustion engine, and a clutch, positioned between the combustion engine and the electric motor, is engagedly and disengagedly controlled so that the clutch is brought into slippage, via partial engagement, to start the combustion engine, and thereafter the clutch is completely disengaged before reaching a synchronous rotational speed between the combustion engine and the electric motor.