Hydraulically controlled actuator for activating a valve

US6857403B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Udo Diehl · Stuttgart, DE
• Karsten Mischker · Leonberg, DE
• Bernd Rosenau · Asperg, DE
• Uwe Hammer · Hemmingen, DE
• Stefan Reimer · Markgröningen, DE
• Volker Beuche · Stuttgart, DE
• Peter Lang · Gelnhausen, DE

Key dates

• Filing date: Jun 25, 2002
• Grant date: Feb 22, 2005
• Expiry date: Jun 25, 2022

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F01L9/10
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

An hydraulically controlled actuator for activating a valve, especially for activating a gas-exchange valve in a combustion cylinder of an internal combustion engine, which includes two fluid-filled pressure chambers having controllable chamber volumes and a movable operating piston which delimits the pressure chambers by piston sides facing away from one another, the operating piston acting upon the valve and having an effective closing area acted upon by fluid pressure in the pressure chambers to close the valve and an effective opening area acted upon by the fluid pressure to open the valve. To influence the kinematics of the opening and closing movement of the valve, the operating piston is such that the surface area of at least one of the two effective areas changes along the sliding path of the operating piston.