Procedure for controlling a hydraulic or pneumatic transmission control unit

US8162799B2 · kind B2 · utility

Assignee

• ZF FRIEDRICHSHAFEN AG · DE

Inventors

• Rupert Kramer · Friedrichshafen, DE
• Marcus Gansohr · Salem, DE
• Johannes Kemler · Ravensburg, DE
• Franz Bitzer · Friedrichshafen, DE
• Rainer Petzold · Friedrichshafen, DE
• Peter Herter · Ravensburg, DE

Key dates

• Filing date: Dec 7, 2009
• Grant date: Apr 24, 2012
• Expiry date: Oct 20, 2030

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H2061/1284
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

A method of monitoring a hydraulic or pneumatic transmission control system, which comprises a pressure supply unit with a conduit directing a pressure medium under a supply pressure, and an actuating member for a clutch control element of a friction clutch. The actuating member has a pressure space which can be connected by a clutch control valve to the conduit, and in which the supply pressure is determined by a pressure sensor that can be connected to the conduit. The method includes the steps of determining the supply pressure by the pressure sensor, given that briefly opening the clutch control valve produces a pressure increase and/or a pressure gradient of the control pressure in the pressure space, and the currently existing supply pressure can be calculated from the control pressure, the pressure increase and/or the pressure gradient.