Control valve assembly for controlling a starting clutch of an automatic transmission

US7771317B2 · kind B2 · utility

Assignee

• ZF FRIEDRICHSHAFEN AG · DE

Inventors

• Georg Gierer · Kreßbronn, DE
• Thilo Schmidt · Meckenbeuren, DE
• Anton Fritzer · Markdorf, DE
• Markus Herrmann · Scheidegg, DE

Key dates

• Filing date: Oct 13, 2006
• Grant date: Aug 10, 2010
• Expiry date: Jul 22, 2027

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S477/906
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

A valve assembly for controlling actuation of at least one starting clutch of an automatic transmission includes at least one clutch control valve through which a supply pressure is directed to a clutch actuation device, a pressure control valve controlled by a control device to supply at least one control valve of the valve assembly with a pilot pressure, a self-maintained hydraulic unit to maintain operation of an engaged starting clutch upon failure of the control device and loss of the pilot pressure. The valve assembly has a self-maintained valve and an activation valve. The self-maintained valve directs an activation pressure or control pressure, depending on the engine or transmission speed, to the activation valve. The actuation valve directs the activation to at least one clutch-regulating valve. The valve assembly also controls actuation or de-activation of the emergency operation function with a clutch actuation pressure.