Drilling tool, particularly for metallic materials

US5704740A · kind A · utility

Assignee

• WALTER AG · DE

Inventors

• Sebastian Ebenhoch · Menomonee Falls, US
• Lothar Fauser · Nehren, DE
• Siegfried Bohnet · Mössingen, DE

Key dates

• Filing date: Jun 26, 1995
• Grant date: Jan 6, 1998
• Expiry date: Jun 26, 2015

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T408/9097
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

Cutting elements or cutter chips (7, 8) are located on a tool body (1). Cutting chip removal spaces (14, 15) are formed in the tool body in three segments. A first segment (I) adjoins the end face (4) of the drill body and includes at least one cutting element seat (10, 11); a chip removal space extends axially, i.e. straight, or slightly obliquely fluted. A second segment (II), adjacent thereto, is formed partially helically with a twist (21) of less than 90.degree. relative to the tool body axis; the second segment (II) terminates axially at a point where, in operation, the direction of radially acting cutting forces coincides essentially with the primary axis of inertia (0-0) of the geometrical moment of inertia. A third segment (III) adjoins the second segment (II); it is essentially straight-fluted.