Flat cutter bit with cutting insert having edge preparation

Patent metadata

Field	Value
Publication number	US-9303511-B2
Application number	US-201313871023-A
Country	US
Kind code	B2
Filing date	Apr 26, 2013
Priority date	Apr 26, 2013
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

A flat cutter bit for engaging an earth strata material includes a non-rotatable shank portion, a head portion integrally formed with the non-rotatable shank portion and including a tip region distal from the non-rotatable shank portion, and a cutting insert mounted at the tip region of the head portion. The cutting insert includes a body having an angled leading face, a top surface having a relief surface, a T-land surface extending between the angled leading face and the relief surface of the top surface and a cutting edge formed at the intersection of the T-land surface and the relief surface of the top surface.

First claim

What is claimed is:

1. A flat cutter bit, the flat cutter bit comprising:
a non-rotatable shank portion;
a head portion integrally formed with the non-rotatable shank portion and including a tip region distal from the non-rotatable shank portion; and
a cutting insert mounted at the tip region of the head portion, wherein the cutting insert comprises:
a body having an angled leading face, wherein the angled leading face is planar;
wherein the body further includes a top surface having a relief surface, a bottom surface, a first side portion and a second side portion;
an arcuate T-land surface extending between the angled leading face and the relief surface of the top surface, wherein the arcuate T-land is contiguous with the angled leading face; and
an arcuate cutting edge formed only at the intersection of the arcuate T-land surface and the relief surface of the top surface,
wherein the arcuate T-land surface and the arcuate cutting edge extend continuously from the first side portion to the second side portion of the body.

2. The flat cutter bit of claim 1 , wherein the arcuate cutting edge has a negative axial rake angle.

3. The flat cutter bit of claim 2 , wherein the negative axial rake angle is in the range of about 10 degrees to about 60 degrees.

4. The flat cutter bit of claim 2 , wherein the arcuate T-land surface is positioned relative to the relief surface of the top surface at an angle that is greater than 90 degrees.

5. The flat cutter bit of claim 1 , wherein the arcuate cutting edge is rounded where the arcuate T-land surface intersects with the relief surface.

6. The flat cutter bit of claim 1 , wherein the arcuate T-land surface has a width in the range of about 0.002 inches to about 0.090 inches.

7. The flat cutter bit of claim 1 , wherein the angled leading face is on an upper section of the body.

8. The flat cutter bit of claim 7 , wherein the body also includes a lower section that has a generally circular cross-sectional shape.

9. A cutting insert for use in connection with a cutter bit, the cutting insert comprising:
a body having an angled leading face, wherein the angled leading face is planar;
wherein the body further includes a top surface having a relief surface, a bottom surface, a first side portion and a second side portion;
an arcuate T-land surface extending between the angled leading face and the relief surface of the top surface, wherein the arcuate T-land is contiguous with the angled leading face; and
an arcuate cutting edge formed only at the intersection of the arcuate T-land surface and the relief surface of the top surface,
wherein the arcuate T-land surface and the arcuate cutting edge extend continuously from the first side portion to the second side portion of the body.

10. The cutting insert of claim 9 , wherein the arcuate cutting edge has a negative axial rake angle.

11. The cutting insert of claim 10 , wherein the negative axial rake angle is in the range of about 10 degrees to about 60 degrees.

12. The cutting insert of claim 10 , wherein the arcuate T-land surface is positioned relative to the relief surface of the top surface at an angle that is greater than 90 degrees.

13. The cutting insert of claim 9 , wherein the arcuate cutting edge is rounded where the arcuate T-land surface intersects with the relief surface.

14. The cutting insert of claim 9 , wherein the arcuate T-land surface has a width in the range of about 0.002 inches to about 0.090 inches.

15. The cutting insert of claim 9 , wherein the angled leading face is on an upper section of the body.

16. The cutting insert of claim 15 , wherein the body also includes a lower section that has a generally circular cross-sectional shape.

Assignees

• Kennametal Inc

Inventors

• Paros Nicholas J
• George Stephen M
• Sheffler Glenn W
• Rowlett Don C

Classifications

• E21C35/183 Primary

  with inserts or layers of wear-resisting material {(drill bits with wear-resistant parts E21B10/46)} · CPC title

• E21C35/1837

  characterised by the shape · CPC title

• E21B10/58

  Chisel-type inserts ({E21B10/485,} E21B10/52 take precedence) · CPC title

• E21C2035/1816

  Fixed Constructions · mapped topic