Knife assembly and chipping knife therefor

• US 7,140,408 B1
• Filed: 02/03/2006
• Issued: 11/28/2006
• Est. Priority Date: 02/03/2006
• Status: Active Grant

• Current Assignee: Key Knife Incorporated
• Original Assignee: Key Knife Incorporated
• Inventors: Hinchliff, Thomas Charles, Liao, Jianmin
• Primary Examiner(s): MILLER, BENA B
• Application Number:
  US11/347,472
• Time in Patent Office: 298 Days
• Field of Search: 144/176, 144/218, 144/230, 144/241, 144/235, 144/162.1, 144/175, 144/174, 241/92, 241/298, 241/189.1, 241/228.1, 241/296, 407/40, 407/42, 407/47, 407113-116
• US Class Current: 144/241
• CPC Class Codes: B27L 11/005 Tools therefor
• CPC Class Codes: Y10T 407/1934 with separate means to fasten tool to holder

Abstract

A knife assembly and chipping knife therefor. The knife assembly includes a knife, and employs an upper clamping member and a lower clamping member for clamping the knife therebetween. The knife has an elongate axis and two spaced apart cutting edges parallel to the elongate axis and defining a first reference plane. The knife is further defined by a plane of reflective symmetry that is perpendicular to the first reference plane and which contains the elongate axis. The knife has a front side and a back side spaced from the front side. The front and back sides terminate in the cutting edges. A deflector ridge projects from the front side and reaches a point of greatest maximum projection of the knife from the first reference plane, the point lying in the plane of reflective symmetry.

Claims

1. A knife having an elongate axis and two spaced apart cutting edges parallel to said elongate axis, said cutting edges defining a reference plane, the knife further defined by a plane of reflective symmetry that is perpendicular to said reference plane and which contains said elongate axis, the knife having a front side and a back side spaced from said front side, said front and back sides terminating in said cutting edges, said front and back sides defining a positive direction, perpendicular to said reference plane, running from said back side toward said front side, a deflector ridge projecting from said front side and reaching a first point of greatest maximum projection of the knife in said positive direction, said point lying in said plane of reflective symmetry, and two substantially identical indexing features of said front side disposed on either side of said deflector ridge and corresponding, respectively, to said two cutting edges, each said indexing feature having a second point of minimum projection of said front side in said positive direction and a third point projecting further in said positive direction than said second point but less than said first point, said first, second and third points all lying in a plane that is perpendicular to both said reference plane and said plane of reflective symmetry, said third point being disposed farther from said plane of reflective symmetry than said second point.

2. The knife of claim 1, wherein said back side includes at least one of (a) a recess and (b) a projection, for indexing the knife.

3. The knife of claim 2, wherein said one of(a) and (b) includes canted sides defining an obtuse angle θ

with respect to said first reference plane.

4. The knife of claim 3, said front side further including two substantially planar knife-edge-joining portions, each knife-edge-joining portion terminating in one of said cutting edges and the third point of the corresponding indexing feature.

5. The knife of claim 4, wherein said knife-edge-joining portions are substantially co-planar.

6. The knife of claim 5, wherein said knife-edge-joining portions lie substantially in said reference plane.

7. The knife of claim 2, said front side further including two substantially planar knife-edge-joining portions, each knife-edge-joining portion terminating in one of said cutting edges and the third point of the corresponding indexing feature.

8. The knife of claim 7, wherein said knife-edge-joining portions are substantially co-planar.

9. The knife of claim 8, wherein said knife-edge-joining portions lie substantially in said reference plane.

10. The knife of claim 1, wherein said indexing features define substantially circular arcs.

11. The knife of claim 10, wherein said back side includes at least one of (a) a recess and (b) a projection, for indexing the knife.

12. The knife of claim 11, wherein said one of (a) and (b) includes canted sides defining an obtuse angle θ

with respect to said first reference plane.

13. The knife of claim 12, said front side further including two substantially planar knife-edge-joining portions, each knife-edge-joining portion terminating in one of said cutting edges and the third point of the corresponding indexing feature.

14. The knife of claim 13, wherein said knife-edge-joining portions are substantially co-planar.

15. The knife of claim 14, wherein said knife-edge-joining portions lie substantially in said reference plane.

16. The knife of claim 11, said front side further including two substantially planar knife-edge-joining portions, each knife-edge-joining portion terminating in one of said cutting edges and the third point of the corresponding indexing feature.

17. The knife of claim 16, wherein said knife-edge-joining portions are substantially co-planar.

18. The knife of claim 17, wherein said knife-edge-joining portions lie substantially in said reference plane.

19. The knife of claim 10, said front side further including two substantially planar knife-edge joining portions, each knife-edge-joining portion terminating in one of said cutting edges and the third point of the corresponding indexing feature.

20. The knife of claim 19, wherein said knife-edge-joining portions are substantially co-planar.

21. The knife of claim 20, wherein said knife-edge-joining portions lie substantially in said reference plane.

22. The knife of claim 1, said front side further including two substantially planar knife-edge-joining portions, each knife-edge-joining portion terminating in one of said cutting edges and the third point of the corresponding indexing feature.

23. The knife of claim 22, wherein said knife-edge-joining portions are substantially co-planar.

24. The knife of claim 23, wherein said knife-edge-joining portions lie substantially in said reference plane.

25. A knife assembly, comprising:

an upper clamping member adapted to receive said back side of the knife;

a lower clamping member adapted to receive said front side of the knife, said upper and lower clamping members for clamping the knife therebetween; and

a knife having an elongate axis and two spaced apart cutting edges parallel to said elongate axis, said cutting edges defining a reference plane, the knife further defined by a plane of reflective symmetry that is perpendicular to said reference plane and which contains said elongate axis, the knife having a front side and a back from said front side, said front and back sides terminating in said cutting edges, said front and back sides defining a positive direction, perpendicular to said reference plane, running from said back side toward said front side, a deflector ridge projecting from said front side and reaching a first point of greatest maximum projection of the knife in said positive direction, said point lying in said plane of reflective symmetry, and two substantially identical indexing features of said front side disposed on either side of said deflector ridge and corresponding, respectively, to said two cutting edges, each said indexing feature having a second point of minimum projection of said front side in said positive direction and a third point projecting further in said positive direction than said second point but less than said first point, said first, second and third points all lying in a plane that is perpendicular to both said reference plane and said plane of reflective symmetry, said third point being disposed farther from said plane of reflective symmetry than said second point.

26. The knife assembly of claim 25, further comprising a base, said lower clamping member for disposition between said upper clamping member and said base and adapted for pivotal movement about said base relative to said upper clamping member.

27. The knife assembly of claim 26, wherein said back side and said upper clamping member include at least one of (a) a recess and a projection, and (b) a projection and a recess, respectively, for indexing said knife to said upper clamping member, wherein said one of (a) and (b) includes canted sides defining obtuse angles θ

₁ and θ

₂ with respect to said first reference plane and corresponding, respectively, to said projection and said recess, where θ

₁>

θ

₂.

28. The knife assembly of claim 26, said front side further including two substantially planar knife-edge-joining portions, each knife-edge-joining portion terminating in one of said cutting edges and the third point of the corresponding indexing feature.

29. The knife assembly of claim 28, wherein said back side and said upper clamping member include at least one of (a) a recess and a projection, and (b) a projection and a recess, respectively, for indexing said knife to said upper clamping member, wherein said one of (a) and (b) includes canted sides defining obtuse angles θ

₁ and θ

₂ with respect to said first reference plane and corresponding, respectively, to said projection and said recess, where θ

₁>

θ

₂.

30. The knife assembly of claim 26, wherein said indexing features define substantially circular arcs.

31. The knife assembly of claim 30, wherein said back side and said upper clamping member include at least one of (a) a recess and a projection, and (b) a projection and a recess, respectively, for indexing said knife to said upper clamping member, wherein said one of (a) and (b) includes canted sides defining obtuse angles θ

₁ and θ

₂ with respect to said first reference plane and corresponding, respectively, to said projection and said recess, where θ

₁>

θ

₂.

32. The knife assembly of claim 30, said front side further including two substantially planar knife-edge-joining portions, each knife-edge-joining portion terminating in one of said cutting edges and the third point of the corresponding indexing feature.

33. The knife assembly of claim 32, wherein said back side and said upper clamping member include at least one of(a) a recess and a projection, and (b) a projection and a recess, respectively, for indexing said knife to said upper clamping member, wherein said one of (a) and (b) includes canted sides defining obtuse angles θ

₁ and θ

₂ with respect to said first reference plane and corresponding, respectively, to said projection and said recess, where θ

₁>

θ

₂.

34. The knife assembly of claim 25, wherein said indexing features define substantially circular arcs.

35. The knife assembly of claim 34, wherein said back side and said upper clamping member include at least one of (a) a recess and a projection, and (b) a projection and a recess, respectively, for indexing said knife to said upper clamping member, wherein said one of (a) and (b) includes canted sides defining obtuse angles θ

₁ and θ

₂ with respect to said first reference plane and corresponding, respectively, to said projection and said recess, where θ

₁>

θ

₂.

36. The knife assembly of claim 34, said front side further including two substantially planar knife-edge-joining portions, each knife-edge-joining portion terminating in one of said cutting edges and the third point of the corresponding indexing feature.

37. The knife assembly of claim 36, wherein said back side and said upper clamping member include at least one of (a) a recess and a projection, and (b) a projection and a recess, respectively, for indexing said knife to said upper clamping member, wherein said one of (a) and (b) includes canted sides defining obtuse angles θ

₁ and θ

₂ with respect to said first reference plane and corresponding, respectively, to said projection and said recess, where θ

₁>

θ

₂.