Rigid connecting duct

US6918359B2 · kind B2 · utility

Assignee

• Andreas Stihl AG & Co. KG · DE

Inventors

• Igor Klaric · Bad Marienberg, DE
• Ernst Buck · Leutenbach, DE

Key dates

• Filing date: May 15, 2003
• Grant date: Jul 19, 2005
• Expiry date: May 15, 2023

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02B25/22
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A portable, manually-guided implement, such as a cut-off machine, is provided and has an internal combustion engine, a cylinder of which has a combustion chamber with an exhaust gas outlet. The combustion chamber is delimited by a piston that, via a connecting rod, drives a crankshaft rotatably mounted in a crankcase. Disposed on both sides of a central plane of the cylinder are transfer channels that respectively connect the crankcase with the combustion chamber. The first end of a transfer channel is connected via an inlet window with the combustion chamber, while the second end of the transfer channel is open toward the crankcase. The transfer channels are connected with an air duct that, via a control member, supplies essentially fuel-free combustion air from an air filter. A duct section of the air duct is formed in a housing wall disposed between the carburetor and the engine cylinder.