Drill insert geometry having V-notched web

• US 7,371,035 B2
• Filed: 02/17/2006
• Issued: 05/13/2008
• Est. Priority Date: 03/27/2001
• Status: Expired due to Term

• Current Assignee: Allied Machine & Engineering Corporation
• Original Assignee: Allied Machine & Engineering Corporation
• Inventors: Mast, Wendell E., Nuzzi, Joseph P.
• Primary Examiner(s): Howell; Daniel W.
• Application Number:
  US11/307,702
• Publication Number:
  US 20060147285A1
• Time in Patent Office: 816 Days
• Field of Search: 408/227, 408/230, 408/229, 408/231, 408/233, 408/713
• US Class Current: 408/230
• CPC Class Codes: B23B 2222/16 Cermet
• CPC Class Codes: B23B 2222/32 Details of high speed steel stainless steel B23B2222/80, steel B23B2222/84
• CPC Class Codes: B23B 2226/125 cubic [CBN]
• CPC Class Codes: B23B 2226/18 Ceramic
• CPC Class Codes: B23B 2226/31 Diamond
• CPC Class Codes: B23B 2226/315 polycrystalline [PCD]
• CPC Class Codes: B23B 2251/02 Connections between shanks and removable cutting heads
• CPC Class Codes: B23B 2251/085 Discontinuous or interrupted cutting edges
• CPC Class Codes: B23B 2251/14 Configuration of the cutting part, i.e. the main cutting edges
• CPC Class Codes: B23B 2251/18 Configuration of the drill point
• CPC Class Codes: B23B 2251/48 Chip breakers
• CPC Class Codes: B23B 2251/50 Drilling tools comprising cutting inserts
• CPC Class Codes: B23B 2270/08 Clamping mechanisms; Provisions for clamping B23B2210/00 takes precedence
• CPC Class Codes: B23B 51/00035 Spade drills
• CPC Class Codes: Y10S 408/713 Tool having detachable cutting edge
• CPC Class Codes: Y10T 408/909 Having peripherally spaced cutting edges
• CPC Class Codes: Y10T 408/9097 Spiral channel
• CPC Class Codes: Y10T 408/90993 Screw driven means

Abstract

The present invention relates to a V-notched web formed on a drill insert of a drill tool assembly. The V-notched web allows greater stability and feed rates, while decreasing the heat generated at the insert tip. The present invention is provided by a drill insert comprising a drill insert body having at least two cutting edges, a web between the two cutting edges, and a web thinning notch formed on either side of the web. Each web thinning notch forms a notch cutting edge having a positive rake angle.

Claims

1. A drill insert comprising:

a drill insert body having a first end opposite a second end, a first face side opposite and parallel to a second face side, a pair of apertures formed through the face sides, and a first land side opposite a second land side, the first and second land sides formed between the ends and the face sides;

wherein at least a portion of the first end of the drill body is a generally planar surface;

wherein the second end comprises at least two main cutting edges formed transverse to each other and substantially parallel to the first and second face sides respectively, a web formed between the two main cutting edges, and a web thinning notch formed on either side of a chisel forming the web;

wherein each web thinning notch forms a notch cutting edge adjacent to and radially inward from one main cutting edge of the at least two main cutting edges, wherein each notch cutting edge has a positive rake angle, wherein the positive rake angle is formed on each notch cutting edge without substantial weakening of the insert at the center portion thereof.

2. The drill insert of claim 1, wherein the generally planar surface of the first side of the drill body has at least one recess formed therein.

4. The drill insert of claim 1, wherein the positive rake angle is produced by forming the web thinning notch with a radius at the bottom of the notch which extends outward from the radius center.

5. The drill insert of claim 1, wherein the web thinning notch is formed using a high skew angle at the location of the chisel at the center of the insert.

3. A drilling tool assembly comprising:

a holder comprising a shank portion, a body portion adjacent the shank portion, the body portion including a holder slot having a bottom seating surface and at least one attachment arm positioned on each side of the holder slot, wherein each attachment arm has at least one aperture formed therein;

a drill insert comprising a first and a second end, a first face side opposite and parallel to a second face side, at least two main cutting edges formed transverse to each other and substantially parallel to the first and second face sides respectively on the second end, a web between the two main cutting edges, and a web thinning notch formed on either side of a chisel forming the web, wherein each notch forms a notch cutting edge having a positive rake angle; and

wherein the drill insert is attached to the holder with at least two fasteners.