Method for operating an internal combustion engine

US8914219B2 · kind B2 · utility

Assignee

• Andreas Stihl AG & Co. KG · DE

Inventors

• Andreas Neubauer · Ludwigsburg, DE
• Jörg Präger · Winnenden, DE

Key dates

• Filing date: Jul 2, 2010
• Grant date: Dec 16, 2014
• Expiry date: Dec 14, 2032

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02D2400/06
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

In a method for operating an internal combustion engine for adjusting a desired fuel/air mixture, wherein the rotary speed is determined by an operating curve based on a fuel/air mixture composition, wherein the operating curve has ascending and descending branches and a maximum, wherein a lambda value is smaller than 1 on the descending branch, it is first determined by statistic evaluation whether the operating point is on the ascending or descending branch. In a second method step, when the operating point is not on a desired branch of the operating curve desired as a starting point for a third method step, at least one operating parameter is changed until the operating point is positioned on the desired branch. In a third method step, the maximum of the operating curve is determined. Based on the determined maximum, the desired operating point of the internal combustion engine is then adjusted.