Method for operating a parking lock device by means of a hydraulic system

US10816091B2 · kind B2 · utility

Assignee

• ZF FRIEDRICHSHAFEN AG · DE

Inventors

• Rainer Novak · Bregenz, AT
• Markus Terwart · Freilassing, DE
• Andreas Roedler · Taufkirchen, DE
• Alexander Hoffmann · Neckargemünd, DE
• Andreas Feiner · Isny im Allgäu, DE
• Tobias Pfleger · Markdorf, DE

Key dates

• Filing date: Mar 20, 2017
• Grant date: Oct 27, 2020
• Expiry date: Jun 11, 2037

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H63/483
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

A method for operating a parking lock device with a hydraulic system, the method including applying the pressure between the parking lock valve and the pressure chamber at the parking lock valve against the actuating force. Moreover, when there is a demand to disengage the parking lock device, the method includes applying the pilot pressure at the parking lock valve against the actuating force when the pressure between the parking lock valve and the pressure chamber of the parking lock valve is less than a threshold value at which the parking lock valve is transferred into a further operating condition range. Additionally, when there is a demand to disengage the parking lock device, the method includes adjusting the pilot pressure applied at the positioning valve to a pressure level at which the positioning valve is transferred into or held in its defined operating condition range.