Operating-mode position selector arrangement for internal combustion engine

US5209196A · kind A · utility

Assignee

• Andreas Stihl AG & Co. KG · DE

Inventors

• Hans Nickel · Cottenweiler, DE
• Michael Wissmann · Markgröningen, DE

Key dates

• Filing date: May 18, 1992
• Grant date: May 11, 1993
• Expiry date: May 18, 2012

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02D2009/0294
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

The invention relates to an operating-mode position selector arrangement for an internal combustion engine in a portable handheld tool such as a motor-driven chain saw. The engine includes an electrical ignition system and is supplied with a fuel mixture by a carburetor. In a start position of the operating-mode position selector, the position selector holds the choke flap and the throttle flap of the carburetor in pregiven start positions. In an operating position of the operating-mode position selector, the throttle flap is released for actuation via a throttle lever and the choke flap is fully opened. In a stop position of the operating-mode position selector, an electric contact is closed between a terminal of the electric ignition system and ground. The different positions of the operating-mode position selector are detected electrically. This is achieved in that for the operating position of the operating-mode position selector, the terminal of the electric ignition system is connected to ground via a further electric contact and a resistor. In this way, the operating position of the operating-mode position selector can be distinguished from the stop position and the start po…