Method and control unit to control a drivetrain

US10053085B2 · kind B2 · utility

Assignee

• ZF FRIEDRICHSHAFEN AG · DE

Inventors

• Joost Peeters · Friedrichshafen, DE
• Felix Klünder · Ravensburg, DE
• Anton Fritzer · Markdorf, DE
• Florian Mayer · Freiberg am Neckar, DE

Key dates

• Filing date: Dec 21, 2016
• Grant date: Aug 21, 2018
• Expiry date: Feb 2, 2037

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/62
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A method for operating a drive train of a motor vehicle includes closing a frictional-locking shift element that serves as a starting element of a transmission in a slipping manner such that slip at the frictional-locking shift element is reduced by a defined pressure control of the frictional-locking shift element, determining a differential rotational speed at the frictional-locking shift element or a variable dependent on the differential rotational speed while the frictional-locking shift element is closing, and, when the differential rotational speed or the variable dependent on the differential rotational speed is less than a first limit value or reaches the first limit value, changing a rotational speed of the drive unit in such a manner that the differential rotational speed or the variable dependent on the differential rotational speed becomes less than a second limit value or reaches the second limit value within a defined time period.