Carbide drill bit for composite materials

• US 7,665,935 B1
• Filed: 07/27/2006
• Issued: 02/23/2010
• Est. Priority Date: 07/27/2006
• Status: Active Grant

• Current Assignee: Precorp, Inc. (Sandvik AB)
• Original Assignee: Precorp, Inc. (Sandvik AB)
• Inventors: Bunting, John A., Garrick, Richard M.
• Primary Examiner(s): Howell; Daniel W
• Application Number:
  US11/494,213
• Time in Patent Office: 1,307 Days
• Field of Search: 408/227, 408223-225, 408/229, 408/230
• US Class Current: 408/227
• CPC Class Codes: B23B 2215/04 Aircraft components
• CPC Class Codes: B23B 2226/27 Composites
• CPC Class Codes: B23B 2226/275 Carbon fibre reinforced carbon composites
• CPC Class Codes: B23B 2251/04 Angles, e.g. cutting angles
• CPC Class Codes: B23B 2251/043 Helix angles
• CPC Class Codes: B23B 2251/082 Curved 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 35/005 Measures for preventing splittering
• CPC Class Codes: B23B 51/02 Twist drills
• CPC Class Codes: Y10T 408/909 Having peripherally spaced cutting edges
• CPC Class Codes: Y10T 408/9097 Spiral channel

Abstract

A drill bit for producing holes in composite materials is disclosed. The drill bit includes an elongate drill bit body having a drill bit diameter. The drill bit also includes at least two helical flutes. The helical flutes have a reverse helix angle and a primary cutting edge. The primary cutting edge may have a positive rake angle. The drill bit further includes a point having a point length. The drill bit may also include a cutting tip with a tip angle and a tip length. The tip length is at least twice the drill bit diameter.

Claims

1. A drill bit for producing holes in composite materials comprising:

an elongate drill bit body having a drill bit diameter;

at least two helical flutes having;

a reverse helix angle of about 0.5 to 10 degrees; and

a primary cutting edge with a positive radial rake angle of at least 6 degrees;

a point having a point length; and

a cutting tip with a tip angle and a tip length of at least twice the drill bit diameter.

2. The drill bit of claim 1, wherein the helical flutes have a helix angle of about 2 to 5 degrees.

3. The drill bit of claim 1, wherein the cutting tip has a tip angle from about 12 to about 30 degrees.

4. The drill bit of claim 1, wherein the cutting tip has a tip angle of about 17 degrees.

5. The drill bit of claim 1, wherein the point length is approximately half the drill bit diameter.

6. The drill bit of claim 1, wherein the point angle is from about 90 to about 135 degrees.

7. The drill bit of claim 1, wherein the point angle is about 118 degrees.

8. The drill bit of claim 1, wherein the primary cutting edge has a hook geometry.

9. The drill bit of claim 1, wherein the drill bit is receivable in one of the following:

a hand drill, a drill press, a mill, a lathe, a CNC mill, or a CNC lathe.

10. A drill bit comprising:

an elongate drill bit body having a drill bit diameter;

at least two helical flutes having;

a reverse helix angle of 0.5 to 10 degrees; and

a primary cutting edge with a positive radial rake angle of at least 6 degrees;

a point having a point length of approximately half the drill bit diameter; and

a cutting tip with a tip angle and a tip length.

11. The drill bit of claim 10, wherein the cutting tip has a tip length of at least twice the drill bit diameter.

12. The drill bit of claim 10, wherein the cutting tip has a tip angle of from about 12 to about 30 degrees.

13. The drill bit of claim 12, wherein the cutting tip has a tip angle of about 17 degrees.

14. The drill bit of claim 13, wherein the primary cutting edge has a hook geometry.

15. The drill bit of claim 14, wherein the point angle is from about 90 degrees to 135 degrees.

16. The drill bit of claim 15, wherein the point angle is 118 degrees.

17. The drill bit of claim 16, wherein the helical flutes have a helix angle of about 2 to 5 degrees.

18. The drill bit of claim 17, wherein the drill bit is receivable in one of the following:

a hand drill, a drill press, a mill, a lathe, a CNC mill, or a CNC lathe.

19. A drill bit for producing holes in composite materials comprising:

an elongate drill bit body having a drill bit diameter;

at least two helical flutes having;

a reverse helix angle of at least 0.5 degrees; and

a primary cutting edge with a positive radial rake angle;

a point having a point length of approximately half the drill bit diameter; and

a cutting tip with a tip angle of approximately 17 degrees and a tip length of at least twice the drill bit diameter.