Handheld work apparatus having an air-cooled combustion engine

US9140204B2 · kind B2 · utility

Assignee

• Andreas Stihl AG & Co. KG · DE

Inventors

• Ernst Gorenflo · Heinsheim, DE
• Eberhard Schieber · Backnang, DE
• Heinrich Leufen · Schwaikheim, DE
• Michael Harrer · Stuttgart, DE
• Claus Naegele · Stuttgart, DE
• Andreas Neubauer · Ludwigsburg, DE

Key dates

• Filing date: Nov 1, 2010
• Grant date: Sep 22, 2015
• Expiry date: Apr 7, 2032

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02D2400/06
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A portable, handheld work apparatus such as a chain saw has a handle (5, 7) to guide the work apparatus (1) and has an air-cooled, mixture-lubricated combustion engine (10) arranged in a casing as a drive for a work tool (3). The cylinder (11) has a combustion chamber (13) formed therein to which an air/fuel mixture is supplied. The air/fuel mixture is ignited by a spark plug (23) which projects into the combustion chamber (13). An ignition control (30) triggers a spark in dependence on the angular position of the crankshaft (15). A temperature sensor (35, 45, 55) is provided to control the cylinder temperature. The temperature signal of the temperature sensor (35, 45, 55) is connected to a power control (40). When a predetermined temperature is exceeded, the power control (40) changes the operating parameters of the combustion engine (10) in such a manner that the power of the combustion engine (10) is changed.