Emergency unlocking device for a parking lock

US8161837B2 · kind B2 · utility

Assignee

• ZF FRIEDRICHSHAFEN AG · DE

Inventors

• Andreas Giefer · Bohmte, DE
• Ludger Rake · Diepholz, DE

Key dates

• Filing date: Dec 5, 2008
• Grant date: Apr 24, 2012
• Expiry date: Dec 5, 2028

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T74/20116
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

An emergency release device for manual actuation of the parking lock of a shift-by-wire transmission. The emergency release device comprises a mechanical transfer device located between an emergency release actuator and the transmission and engages a pivoting lever mechanism arranged on a transmission shifting shaft. A characterizing feature of the emergency release device is that the pivoting lever mechanism comprises a primary pivoting lever connected to the transfer device, a secondary pivoting lever connected to the transmission and a unidirectional coupling element located between the primary and the secondary pivoting levers. The advantage of this device relates to reduced susceptibility to corrosion, wear and noise emission and easier correct adjustment of the transfer device during assembly, while a separate prestressing mechanism for the cable of the emergency parking lock release can be omitted.