Two-cycle engine having scavenging

US7131406B2 · kind B2 · utility

Assignee

• Andreas Stihl AG & Co. KG · DE

Inventors

• Bernhard Durr · Stuttgart, DE
• Harald Schliemann · Waiblingen, DE
• Jorg Schlossarczyk · Winnenden, DE
• Werner Geyer · Newton, US

Key dates

• Filing date: Jan 17, 2003
• Grant date: Nov 7, 2006
• Expiry date: Aug 22, 2023

Classification

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

Abstract

A two-cycle engine in a portable, manually-guided implement, such as a power chain saw, a cut-off machine, a brush cutter, or the like, is provided. The cylinder has a combustion chamber that is delimited by a reciprocating piston that via a connecting rod drives a crankshaft that is mounted in a crankcase so as to be rotatable about a crankshaft axis. The cylinder has an outlet for conveying exhaust gases out of the combustion chamber, with the outlet having an axis of the channel thereof. The cylinder also has an inlet for supplying a fuel/air mixture to the crankcase. By means of at least two transfer channels, the fuel/air mixture is conveyed out of the crankcase and into the combustion chamber, with the transfer channels being disposed symmetrically relative to the axis of the channel of the outlet. When viewed in the direction of the longitudinal axis of the cylinder, the axis of the channel of the outlet is disposed at an angle of less than 90° relative to the longitudinal central axis of the crankshaft.