Hand-held working tool

US6314922A · kind A · utility

Assignee

• Andreas Stihl AG & Co. KG · DE

Inventors

• Helmut Zimmermann · Winnenden, DE
• Werner Geyer · Newton, US
• Jorg Schlossarczyk · Winnenden, DE
• Hans Nickel · Cottenweiler, DE
• Harald Schliemann · Waiblingen, DE
• Gunter Stein · Windom, US
• Peter Stucke · Virginia Beach, US
• Bernhard Durr · Stuttgart, DE
• Axel Klimmek · Schwaikheim, DE

Key dates

• Filing date: Jul 23, 1999
• Grant date: Nov 13, 2001
• Expiry date: Jul 23, 2019

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/12
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A hand-held working tool has a housing and an internal combustion engine arranged in the housing and comprising a crankshaft and an air filter. A tool is driven by the crankshaft of the internal combustion engine. A fan housing is attached to the engine housing and has an air inlet. A fan wheel is arranged in the fan housing and is driven by the crankshaft of the internal combustion engine to supply cooling air, sucked in through the air inlet, to the internal combustion engine. The fan housing has a bottom extending radially to the crankshaft. The bottom and a side of the fan wheel facing the bottom define a chamber in the fan housing. The bottom has a combustion air outlet. A combustion air channel is connected to the combustion air outlet and to the air filter. The combustion air outlet is axially supplying combustion air from the chamber through the combustion air channel into the air filter of internal combustion engine. The fan housing has a channel wall having a bottom portion connected to the face of the bottom remote from the fan wheel and covering the bottom partially to form a double-walled bottom. The end face portion of the combustion air channel is defined by the bott…