Cutting tool with enhanced chip evacuation capability and method of making same

Patent metadata

Field	Value
Publication number	US-9878379-B2
Application number	US-201514693063-A
Country	US
Kind code	B2
Filing date	Apr 22, 2015
Priority date	Apr 22, 2015
Publication date	Jan 30, 2018
Grant date	Jan 30, 2018

Abstract

A milling cutter includes a shank and a cutting head attached to the shank. The cutting head has a plurality of helical teeth, each tooth including a cutting tip, a leading face and a rear face. A flute is defined between the leading face of a trailing tooth, and a rear face of an immediately preceding tooth. A gully of the flute has a flute base with a portion that is planar or convex in profile to provide additional volume for effective chip evacuation. A method for manufacturing the milling cutter includes rotating a cylindrical blank about its own longitudinal axis, rotating a disc-shaped flute grinding wheel) about a rotational axis of a flute wheel and moving the grinding wheel in a longitudinal direction so as to form the helical flute with the gully having the flute base with the planar or convex portion in profile.

First claim

What is claimed is:

1. A milling cutter, comprising:
a shank;
a cutting head attached to the shank, the cutting head having a plurality of helical teeth, each tooth including a cutting tip, a leading face and a rear face; and
a flute disposed between the leading face of a trailing tooth, and the rear face of an immediately preceding tooth, wherein a gully of the flute has a flute base with a portion that is generally planar in profile to provide additional volume for effective chip evacuation.

2. The milling cutter of claim 1 , wherein the gully has a shape resulting from formation in a single path grinding process that employs a grinding wheel with a first grinding portion and a second grinding portion.

3. The milling cutter of claim 2 , wherein the gully shape results from:
the first grinding portion being planar and formed at a first angle with respect to a plane that is perpendicular to a longitudinal axis of the milling cutter; and
the second grinding portion being planar and formed at a second angle with respect to the plane, the second angle being different than the first angle.

4. The milling cutter of claim 3 , wherein the gully shape results from the first angle being larger than the second angle.

5. The milling cutter of claim 2 , wherein the gully shape results from:
the first grinding portion having a first length, and wherein the second grinding portion has a second length, the second length different than the first length.

6. The milling cutter of claim 1 , wherein the leading face has a positive or negative radial rake angle.

7. The milling cutter of claim 1 , wherein each tooth further comprises a planar primary relief rake facet.

8. The milling cutter of claim 1 , wherein the primary relief rake facet has a primary clearance angle of 5-10 degrees.

9. The milling cutter of claim 1 , wherein a wedge angle of each tooth is between 60-90 degrees.

10. The milling cutter of claim 1 , wherein the teeth are spaced from one another via unequal indexing.

11. The milling cutter of claim 1 , wherein:
the milling cutter defines a core diameter and a cutting diameter; and
via the generally planar portion of the flute base, the milling cutter has a larger core diameter than a milling cutter having:
a similar cutting diameter; and
a flute with a gully that is continuously rounded or radiused.

12. The milling cutter of claim 11 , comprising:
a plurality of flutes each disposed between a pair of neighboring teeth;
wherein each flute has a gully, each gully comprising a base with a portion that is generally planar in profile to provide additional volume for effective chip evacuation.

13. The milling cutter of claim 11 , wherein each tooth further comprises a planar primary relief rake facet.

14. The milling cutter of claim 11 , wherein the teeth are spaced from one another via unequal indexing.

Assignees

• Kennametal Inc

Inventors

• Davis Danny Ray

Classifications

• B23C2210/40

  Flutes, i.e. chip conveying grooves · CPC title

• B24B3/021

  of milling cutters with helical cutting edges · CPC title

• B23C5/10 Primary

  Shank-type cutters, i.e. with an integral shaft · CPC title

• B23C2210/0435

  radial rake angle · CPC title

• B23C2210/241

  Cross sections of the whole milling cutter · CPC title