Protective shield for a free-cutting tool

US7406771B2 · kind B2 · utility

Assignee

• Andreas Stihl AG & Co. KG · DE

Inventors

• Helmut Zimmermann · Winnenden, DE
• Roland Schierling · Marbach am Neckar, DE
• Johannes Menzel · Oberhausen, DE
• Kai-Ulrich Machens · Stuttgart, DE

Key dates

• Filing date: Jul 17, 2006
• Grant date: Aug 5, 2008
• Expiry date: Jul 17, 2026

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A01D34/90
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

A protective shield (2) is provided for a free-cutting tool (1). The free-cutting tool has a cutterhead (4) rotatable about a rotational axis (3) and carries a cutting filament (5). For a rotating cutterhead (4), the cutting filament (5) rotates in a rotational direction (10), aligns itself approximately radially to the rotational axis (3) and defines a cutting circle (6) having a constructively pregiven nominal radius (R). The cutting radius (6) is at least partially covered by the protective shield (2). A cut-to-length knife (7) having a cutting edge (8) for cutting the cutting filament (5) to length is mounted on the protective shield (2) in the peripheral region thereof. The cut-to-length knife (7) is mounted on the protective shield (2) to be moveable back and forth between a cutting position (11) and a rest position (12). The cutting edge (8) lies in the plane of the cutting circle (6) in the cutting position (11) and has the nominal radius (R) to the rotational axis (3) and, in the rest position (12), the cutting edge (8) lies outside of the cutting circle (6).