Adjustable pulley for fluid-operated transmissions

US6361470B1 · kind B1 · utility

Assignee

• LüK Lamellen und Kupplungsbau GmbH · DE

Inventors

• Oswald Friedmann · Lichtenau, DE
• Bernhard Walter · Oberkirch, DE

Key dates

• Filing date: May 25, 2000
• Grant date: Mar 26, 2002
• Expiry date: May 25, 2020

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H61/66272
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

An adjustable pulley for use in a continuous variable transmission in the power train of a motor vehicle has an axially fixed first conical flange and an axially movable second conical flange. The hydraulic control system which moves the second flange relative to the first flange is provided with at least one first plenum chamber which receives pressurized fluid when the second flange is to move toward the first flange, and with an additional plenum chamber which receives pressurized fluid when the second flange is to move away from the first flange. The admission of pressurized fluid into the additional chamber is regulated in dependency upon the RPM of the flanges. Rapid evacuation of pressurized fluid from the additional chamber can take place by way of a relief valve which opens when the pressure of fluid in the additional chamber rises to a preselected value. This renders it possible to rapidly shift between overdrive and underdrive.