Method for controlling an automatic transmission

US6597978B1 · kind B1 · utility

Assignee

• ZF FRIEDRICHSHAFEN AG · DE

Inventors

• Ralf Dreibholz · Meckenbeuren, DE
• Hans-Jorg Domian · Markdorf, DE

Key dates

• Filing date: May 24, 2001
• Grant date: Jul 22, 2003
• Expiry date: May 24, 2021

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H63/502
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A method is proposed for controlling an automatic transmission driven by a prime mover in which a shift from a first transmission ratio to a second transmission ratio occurs in the form of a pull upshift or push downshift or a pull downshift or push upshift by a first clutch opening and a second clutch closing and an electronic transmission control device controls, via electromagnetic valves, the pressure curve of the first and of the second clutch during the shifting operation. The shifting operation is divided into various shifting phases, an engine intervention taking place in the load-transfer (LÜ) of the gradient-setting phase (GE), the sliding phase (GL), the gradient-reduction phase (GA) and the closing phase (S), an engine torque and/or a characteristic value that determines the engine torque being transferred from the transmission control device to an engine control device of the prime mover.