Method for operating a pneumatic actuating system of a transmission and control device for carrying out the method

US10794477B2 · kind B2 · utility

Assignee

• ZF FRIEDRICHSHAFEN AG · DE

Inventors

• Alain Tierry Chamaken Kamde · Friedrichshafen, DE
• Wilhelm Moser · Markdorf, DE

Key dates

• Filing date: Nov 17, 2017
• Grant date: Oct 6, 2020
• Expiry date: Nov 17, 2037

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H2061/1292
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

A method for operating a pneumatic actuating system of a transmission. The actuating system has an air reservoir at a first pressure. The reservoir couples an actuating space of the actuating system which is at a second pressure, and the actuating space couples, via control valves, shifting cylinders. When conducting a transmission gearshift, an air mass delivered to the active shifting cylinders via corresponding control valves, and an air mass sum including a nominal air mass in the active cylinders required for accomplishing the gearshift and an actual basic leakage from the activated shifting cylinder are determined. A defect leak in the pneumatic actuating system is recognized, if the air mass delivered to the active shifting cylinders is larger than the air mass sum. If a defect leak is recognized, the control valves coupling the actuating space and the shifting cylinders are shut off for a period of time.