Two-stroke engine

US8671897B2 · kind B2 · utility

Assignee

• Andreas Stihl AG & Co. KG · DE

Inventors

• Werner Geyer · Newton, US
• Mark Reichler · Winnenden, DE
• Robert Köhli · Winnenden, DE
• Evelyn Kullik · Gerlingen, DE
• Helmut Schlessmann · Waiblingen, DE

Key dates

• Filing date: Dec 19, 2011
• Grant date: Mar 18, 2014
• Expiry date: Jul 31, 2032

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02B2075/025
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

An engine has a cylinder wherein a reciprocating piston is mounted. The piston drives, via a connecting rod (6), a crankshaft (7) pivotably mounted in a crankcase. The connecting rod is connected to the piston via a piston pin. An inlet window for combustion air is provided and controlled by the piston. The piston separates a combustion chamber from the crankcase interior space and has a piston base the underside of which is oriented toward the crankcase. To achieve good cooling of the piston and of the piston pin bearing, a first flow-guide element is provided within the crankcase interior space adjacent to the inlet window. The first flow-guide element redirects the combustion air flowing in through the inlet window in the direction of the underside of the piston base.