Two-stroke internal combustion engine with flushing channels

US5813373A · kind A · utility

Assignee

• Andreas Stihl AG & Co. KG · DE

Inventors

• Jorg Schlossarczyk · Winnenden, DE
• Axel Klimmek · Schwaikheim, DE
• Peter Pretzsch · Schorndorf, DE

Key dates

• Filing date: May 7, 1997
• Grant date: Sep 29, 1998
• Expiry date: May 7, 2017

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-stroke internal combustion engine for a hand-guided working tool has a cylinder with a cylinder wall and a piston reciprocating in the cylinder and defining a combustion chamber with the cylinder wall. Transfer parts, each having an outlet window, for introducing combustion air and fuel into the combustion chamber are provided. The outlet windows are cut into the cylinder wall for connecting the transfer parts to the combustion chamber. The outlet windows have limiting edges extending parallel to a central cylinder axis of the cylinder and are located within an inner mantle surface of the cylinder wall. The outlet windows have a window width measured in a circumferential direction of the inner mantle surface. The transfer parts have a channel width measured in the circumferential direction of the inner mantle surface, whereby the window width is greater than the channel width. The transfer parts have a transition portion into the outlet windows. The transfer parts have a flow stall edge at an end of the transition portion remote from the outlet windows. The flow stall edges extend parallel to the central cylinder axis.