Cutting Tool

Abstract

A mill has a front cutting portion with a plurality of peripheral cutting edges extending rearwardly from a front cutting end. Each peripheral cutting edge is adapted to generate a corresponding outer envelope of a body of revolution as the mill rotates around its longitudinal axis. At least one cutting edge is adapted to generate a cylindrical outer envelope; at least one cutting edge is adapted to generate a generally frusto-conical taper outer envelope extending away from the front cutting end while tapering radially outwardly; and at least one cutting edge is adapted to generate a generally frusto-conical dovetail outer envelope extending away from the front cutting end while tapering radially inwardly.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present disclosure and to show how the same may be carried out in practice, reference will now be made to the accompanying drawings, in which:

FIG. 1 shows a perspective view of a mill in accordance with a first exemplar embodiment of the present disclosure;

FIG. 2 shows a side elevational view of a cutting portion of the mill shown in FIG. 1;

FIG. 3 shows a section view of the cutting portion taken along the line III-III of FIG. 2;

FIG. 4 shows a section view of the cutting portion taken along the line IV-IV of FIG. 2;

FIG. 5A shows a schematic depiction of the outer envelope generated by a taper tooth of the mill shown in FIG. 1;

FIG. 5B shows a schematic depiction of the outer envelope generated by a dovetail tooth of the mill shown in FIG. 1;

FIG. 5C shows a schematic depiction of the outer envelope generated by a cylindrical tooth of the mill shown in FIG. 1;

FIG. 6 shows a perspective view of a mill in accordance with a second exemplar embodiment of the present disclosure;

FIG. 7 shows a side view of the mill shown in FIG. 6;

FIG. 8A shows a side view of a cylindrical pocket of the mill shown in FIG. 6;

FIG. 8B shows a side view of a taper pocket of the mill shown in FIG. 6; and

FIG. 8C shows a side view of a dovetail pocket of the mill shown in FIG. 6.

Claims

1. A mill having a longitudinal axis and a direction of rotation thereabout comprising: a front cutting end;at least one first cutting edge extending rearwardly from the front cutting end and being adapted to generate a generally cylindrical outer envelope;at least one second cutting edge extending rearwardly from the front cutting end and being adapted to generate a first generally frusto-conical outer envelope tapering radially outward when proceeding along the longitudinal axis away from the front cutting end; andat least one third cutting edge extending rearwardly from the front cutting end and being adapted to generate a second generally frusto-conical outer envelope tapering radially inward when proceeding along the longitudinal axis away from the front cutting end.

2. The mill according to claim 1 further comprising a rear cutting end and wherein the generally cylindrical outer envelope has a cylindrical radius, the first generally frusto-conical outer envelope has a first taper termination radius adjacent the rear cutting end, the second generally frusto-conical outer envelope has a second taper front radius adjacent the front cutting end, and the first taper termination radius and the second taper front radius are at least approximately equal to the cylindrical radius.

3. The mill according to claim 1 further comprising a rear cutting end and wherein the generally cylindrical outer envelope has a cylindrical radius, the first generally frusto-conical outer envelope has a first taper front radius adjacent the front cutting end, the second generally frusto-conical outer envelope has a second termination radius adjacent the rear cutting end and the first taper front radius and the second termination radius are less than the cylindrical radius.

4. A mill having a longitudinal axis and a direction of rotation thereabout comprising: a forwardly facing cutting portion face;a front cutting portion extending longitudinally from the forwardly facing cutting portion face to a rear termination; anda plurality of helical teeth comprising:at least a first helical tooth integrally formed along at least a portion of the front cutting portion and having a first peripheral cutting edge adapted to generate a generally cylindrical outer envelope as the mill rotates;at least a second helical tooth integrally formed along at least a portion of the front cutting portion and having a second peripheral cutting edge adapted to generate a first generally frusto-conical outer envelope tapering radially outward when proceeding along the longitudinal axis away from the cutting portion face; andat least a third helical tooth integrally formed along at least a portion of the front cutting portion and having a third peripheral cutting edge adapted to generate a second generally frusto-conical outer envelope tapering radially inward when proceeding along the longitudinal axis away from the cutting portion face.

5. The mill according to claim 4 wherein: the cylindrical outer envelope has a generally cylindrical radius;the first generally frusto-conical outer envelope has a termination radius adjacent the rear termination;the second generally frusto-conical outer envelope has a front radius adjacent the cutting portion face; andwherein the termination radius and the front radius are at least approximately equal to the cylindrical radius.

6. The mill according to claim 4 wherein the plurality of helical teeth comprise an even number of helical teeth.

7. The mill according to claim 4 wherein at least two first peripheral cutting edges disposed opposite of each other generate the generally cylindrical outer envelope.

8. The mill according to claim 7 wherein at least one of the second peripheral cutting edge and the third peripheral cutting edge is disposed between the at least two first peripheral cutting edges.

9. A mill having a longitudinal axis and a direction of rotation thereabout comprising: a cutting portion having a front cutting end;a plurality of inserts secured around a perimeter of the cutting portion;each of the plurality of cutting inserts comprising a peripheral edge extending rearwardly from a front corner adjacent the front cutting end to a rear corner;each peripheral edge being adapted to generate a corresponding outer envelope as the mill rotates; andwherein a first corresponding outer envelope comprises a generally cylindrical outer envelope, and a second corresponding outer envelope comprises a frustro-conical outer envelope tapering radially outward when proceeding along the longitudinal axis away from the front cutting end.

10. The mill according to claim 9 wherein the first corresponding outer envelope has a cylindrical radius and the second corresponding outer envelope has a taper termination radius adjacent the rear corner that is at least approximately equal to the cylindrical radius.

11. The mill according to claim 9 further comprising a third corresponding outer envelope comprising a frustro-conical outer envelope tapering radially inward when proceeding along the longitudinal axis away from the front cutting end.

12. The mill according to claim 11 wherein the first corresponding outer envelope has a cylindrical radius and the third corresponding outer envelope has a front radius adjacent the front corner that is at least approximately equal to the cylindrical radius.

13. The mill according to claim 9 wherein the plurality of inserts comprises at least six inserts.

14. The mill according to claim 9 wherein at least two peripheral cutting edges disposed opposite of each other generate the generally cylindrical outer envelope.

15. The mill according to claim 14 wherein at least one peripheral cutting edge adapted to generate at least one of a group comprising the second corresponding outer envelope and the third corresponding outer envelope is disposed between the at least two first peripheral disposed opposite of each other generating the generally cylindrical outer envelope.

16. The mill according to claim 9 wherein at least some of the plurality of cutting inserts may be removed from the front cutting end.

17. The mill according to claim 9 wherein all of the cutting inserts are substantially identical.

18. A mill having a longitudinal axis and a direction of rotation thereabout comprising: a cutting portion having a front cutting end;a plurality of pockets around a perimeter of the front cutting end;each of the plurality of pockets adapted to releasably secure a cutting insert;at least a first pocket of the plurality of pockets adapted such that a peripheral edge of a cutting insert secured in the first pocket generates a corresponding cylindrical first outer envelope as the mill rotates;at least a second pocket of the plurality of pockets adapted such that a peripheral edge of a cutting insert secured in the second pocket generates a corresponding frustro-conical second outer envelope tapering radially outward when proceeding along the longitudinal axis away from the front cutting end as the mill rotates;at least a third pocket of the plurality of pockets adapted such that a peripheral edge of a cutting insert secured in the third pocket generates a corresponding frustro-conical third outer envelope tapering radially inward when proceeding along the longitudinal axis away from the front cutting end as the mill rotates.

19. The mill according to claim 18 wherein the first outer envelope has a cylindrical radius and the second outer envelope has a taper termination radius adjacent a rear corner of a peripheral edge of an insert releasably secured into the second pocket that is at least approximately equal to the cylindrical radius.

20. The mill according to claim 18 wherein the first outer envelope has a cylindrical radius and the third outer envelope has a front radius adjacent a front corner of a peripheral edge of an insert releasably secured into the third pocket that is at least approximately equal to the cylindrical radius.

21. The mill according to claim 18 wherein at least two first pockets are disposed opposite of each other on the front cutting end.

22. The mill according to claim 18 wherein at least one of a group comprising at least one of the second pockets and at least one of the third pockets is disposed between the at least two first pockets.