Hydrokinetic torque converter with lockup clutch

US5779012A · kind A · utility

Assignee

• LuK Getriebe-Systeme GmbH · DE

Inventors

• Volker Middelmann · Wooster, US
• Marc Meisner · Bühl, DE
• Jürgen Freitag · Ottersweier, DE

Key dates

• Filing date: Aug 5, 1997
• Grant date: Jul 14, 1998
• Expiry date: Aug 5, 2017

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H2059/385
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

The housing of a hydrokinetic torque converter in the power train between the engine and the transmission of a motor vehicle contains a lockup valve which can be engaged to transmit torque directly from the output element of the engine to the output member of the turbine in the housing. Engagement of the lockup clutch at a relatively low RPM of the engine and/or under certain other circumstances is prevented or minimized by the provision of one or more valves which are designed to establish or to at least partially seal one or more paths for direct flow of hydraulic fluid between two compartments forming part of a chamber in the housing of the torque converter and being disposed at opposite sides of the axially movable piston of the lockup clutch. The valve or valves can be designed to react in response to changing RPM of the housing of the torque converter, in response to changes of the temperature of hydraulic fluid in the housing and/or in response to changes of the viscosity of such fluid. The valving element or elements of the valve or valves can be caused to change its or their position(s) relative to the respective path(s) in response to the action of centrifugal force and/o…