Two-stroke engine

US7363888B2 · kind B2 · utility

Assignee

• Andreas Stihl AG & Co. KG · DE

Inventors

• Axel Klimmek · Schwaikheim, DE
• Silke Kaminski · Waiblingen, DE
• Werner Geyer · Newton, US
• Roland Schmidt · Lakewood, US
• Tommy Roitsch · Waiblingen, DE
• Ralf Blechsmidt · Weingarten, DE
• Andreas Bähner · Waiblingen, DE
• Olaf Schmidt · Heidelberg, DE

Key dates

• Filing date: Jan 13, 2006
• Grant date: Apr 29, 2008
• Expiry date: Jan 13, 2026

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02B25/16
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A two-stroke engine has a cylinder and a piston reciprocating in the cylinder and delimiting a combustion chamber. The piston has at least one piston recess. A crankshaft is rotatably arranged in a crankcase connected to the cylinder. A connecting rod connects piston and crankshaft. Transfer channels connect the crankcase to the combustion chamber in pre-defined piston positions. The transfer channels each have a transfer port opening into the combustion chamber. A device for supplying fuel and an air channel supplying combustion air are provided. In predetermined piston positions, the air channel is connected by the piston recess to the transfer ports. The air channel opens into the cylinder bore opposite the exhaust for the exhaust gases. The air channel, the piston recess, and the transfer channels define an air passage that provides approximately uniform distribution of air from the air channel into the transfer channels.