Valve control for internal combustion engines

US4452186A · kind A · utility

Assignee

• Dr. Ing. h.c. F. Porsche AG · DE

Inventors

• Rainer List · Renningen, DE
• Klaus Schellmann · Weinsberg, DE
• Heinz Schulze · Dresden, DE

Key dates

• Filing date: Feb 9, 1981
• Grant date: Jun 5, 1984
• Expiry date: Feb 9, 2001

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F01L2001/34446
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A valve control for internal combustion engines comprising a hydraulic arrangement between a cam shaft and a cylinder head valve, the hydraulic arrangement including a piston system having at least a power piston cooperable with the cam shaft and an activating piston, a housing within which at least the actuating piston of the piston assembly is contained and a damping means for controlling valve seating operation. The hydraulic arrangement forms part of a means for varying the stroke and opening time of the cylinder head valve in response to at least one operating parameter of the internal combustion engine, and the means for varying the stroke and opening time also includes a throttle element for influencing the piston system, the throttle element being controlled by the noted at least one operating parameter of the internal combustion engine. In accordance with one embodiment, the piston system comprises at least three pistons, at least a drive piston being provided in addition to the power and actuating pistons, the drive piston having the piston valve therein.