Process for automatically co-ordinating the filling operation of shift elements

US6101438A · kind A · utility

Assignee

• ZF FRIEDRICHSHAFEN AG · DE

Inventors

• Kai Staiger · Friedrichshafen, DE
• Ralf Dreibholz · Meckenbeuren, DE
• Gerd Frotscher · Friedrichshafen, DE

Key dates

• Filing date: May 19, 1998
• Grant date: Aug 8, 2000
• Expiry date: May 19, 2018

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H2342/04
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

A process is proposed for automatically coordinating the filling and feeding operation of hydraulically operated and hydraulically or electronically individually commanded shift elements. The filling and feeding operation is divided into a rapid filling phase and a filling equalization phase and has as parameters at least one rapid filling period, one rapid filling pressure, one filling equalization period and one filling equalization pressure. To optimize said parameters two of the four are preset and for the other two, an optimal value is determined for the first parameter to be optimized on the basis of a preset, time-dependent pressure curve in which a pressure increase phase follows the rapid filling phase and equalization phase. To this end, based on an initial value presettable in each case, the first parameter is gradually adjusted until a speed change occurs at or before the start of the pressure increase phase. For the other parameter to be optimized, at the optimal value of the first parameter to be optimized and based on the respective presettable initial value, said parameter is gradually changed until a speed change occurs before or at least approximately simultaneous…