Multicylinder internal combustion engine, especially for automobiles and method of operating same

US4305249A · kind A · utility

Assignee

• Dr. Ing. h.c. F. Porsche AG · DE

Inventors

• Wolfgang Schmid · Regensburg, DE
• Klaus Schellmann · Weinsberg, DE

Key dates

• Filing date: Nov 2, 1979
• Grant date: Dec 15, 1981
• Expiry date: Nov 2, 1999

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02A50/20
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A multicylinder internal combustion engine is provided with fuel-air mixture feed devices associated with two different cylinders or groups of cylinders, and an exhaust conduit system in which two catalyzers are disposed, one downstream of the other. The exhaust produced by the first group of cylinders impinges on both catalyzers, while the exhaust of the second group of cylinders is fed through only the second catalyzer. During a predetermined partial load range, fuel is supplied only to one of the cylinder groups, while both cylinder groups are fed with fuel once this load range is exceeded. In a preferred embodiment, the turning on of fuel to the second cylinder group is effectuated by a cam disk that also serves the function of simultaneously controlling the supply of air through throttle valves to the respective cylinder groups.