Continuously variable transmission

US6890275B1 · kind B1 · utility

Assignee

• ZF FRIEDRICHSHAFEN AG · DE

Inventors

• Andreas Piepenbrink · Meersburg, DE
• Bernd Fessler · Kreßbronn, DE
• Wolfgang Runge · Ravensburg, DE

Key dates

• Filing date: Apr 15, 2000
• Grant date: May 10, 2005
• Expiry date: Apr 15, 2020

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H61/66263
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

A continuously variable transmission for a motor vehicle, possessing a variator (2, 2′) with a primary V-pulley set (3, 3′) and a secondary V-pulley set (4, 4′). In this arrangement are a primary V-pulley disk (5, 5′) and a secondary V-pulley disk (6, 6′), which are axially slidable by hydraulic force for the controlled adjustment of a pressure can be, respectively, loaded with an oil flow through an electro-hydraulically controlled pressure supply apparatus (1, 1′). The pressure supply apparatus (1,1′) is so designed, that the oil flow is brought to the V-pulley disks (5, 5′, 5, 6′) through a pressure line (8, 8′, 9, 9′) with at least one pressure controller (10, 10′, 11, 11′) and one pressure chamber (12, 12′, 13, 13′) with a variable volume (V1, V2). The pressure chamber (12, 12′) of the primary V-pulley disk (5, 5′) can be connected to a primary chamber 20, 20′) of the cylinder (14, 14′), and the pressure chamber (13, 13′) can be connected with a secondary chamber (21, 21′) of said cylinder (14, 14′), in which, between the primary chamber (20, 20′) and the secondary chamber (21, 21′) a double action, reversible piston (15, 15′) is placed for directing pressurized oil from a low…