U.S. patent application number 09/727027 was filed with the patent office on 2001-04-12 for cutting tools for drilling concrete, aggregate, masonry or the like materials.
This patent application is currently assigned to Black & Decker Inc.. Invention is credited to Anjanappa, Muniswamappa, Crosby, Stephen R., Timmons, Russell M., Williams, John D..
Application Number | 20010000224 09/727027 |
Document ID | / |
Family ID | 23392924 |
Filed Date | 2001-04-12 |
United States Patent
Application |
20010000224 |
Kind Code |
A1 |
Anjanappa, Muniswamappa ; et
al. |
April 12, 2001 |
Cutting tools for drilling concrete, aggregate, masonry or the like
materials
Abstract
A cutting tool (200, 202) has a longitudinally extending shaft
portion (208) with a chucking part (204) and a cutting head (206).
A cutting edge (220) is formed on the cutting head (206). The
cutting edge (220) includes at least one cutting portion. A rake
surface (224) is formed adjacent to at least one of the cutting
portions (220) with the rake face being at a rake angle in the
range from about -10.degree. to about 10.degree.. A clearance face
(226) is formed adjacent to the at least one cutting portion
opposite the rake face (224). The clearance face (226) is at a
clearance angle in the range from about 10.degree. to about
50.degree.. An edge radius between the rake face and the clearance
face is at a radius of from about 0.0003 to about 0.0040 inch.
Inventors: |
Anjanappa, Muniswamappa;
(Columbia, MD) ; Crosby, Stephen R.; (White Hall,
MD) ; Timmons, Russell M.; (Lutherville, MD) ;
Williams, John D.; (Champaign, IL) |
Correspondence
Address: |
Harness, Dickey & Pierce, P.L.C.
P.O. Box 828
Bloomfield Hills
MI
48303
US
|
Assignee: |
Black & Decker Inc.
|
Family ID: |
23392924 |
Appl. No.: |
09/727027 |
Filed: |
November 30, 2000 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09727027 |
Nov 30, 2000 |
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08837828 |
Apr 22, 1997 |
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6174111 |
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08837828 |
Apr 22, 1997 |
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08354349 |
Dec 12, 1994 |
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Current U.S.
Class: |
408/230 ;
408/144 |
Current CPC
Class: |
B23B 2251/14 20130101;
B23B 2226/75 20130101; Y10T 408/9097 20150115; Y10T 408/03
20150115; Y10T 408/909 20150115; B23B 2251/48 20130101; E21B 10/445
20130101; B23B 2251/04 20130101; B23B 51/02 20130101; Y10T 408/78
20150115; B23B 2251/18 20130101 |
Class at
Publication: |
408/230 ;
408/144 |
International
Class: |
B23B 051/02 |
Claims
What is claimed is:
1. A cutting tool for forming a hole in concrete or the like
material, comprising: a longitudinally-extending shank portion
defining a longitudinal axis and having two ends; a chucking part
provided at one end of the shank portion; a cutting head provided
at the other end of said shank portion, a cutting edge formed on
said cutting head, said cutting edge having at least one cutting
edge portion; a reference plane, which is parallel to a centerline
of said cutting tool and through said cutting tool and through said
cutting edge when said cutting edge is viewed as a point; a rake
face formed adjacent said cutting edge, and said rake face being at
a rake angle in the range of from about -10.degree. to about
10.degree. such that positive angles are defined by clockwise
rotation about a point on the cutting edge portion from said
reference plane at said cutting edge to said rake face, when viewed
along said cutting edge from an outside diameter of said cutting
tool, and negative rake angles are defined by counterclockwise
rotation about said point on said cutting edge from said reference
plane to said rake face, when viewed along said cutting edge from
the outside diameter of said cutting tool and measured in an area
between said cutting edge and said chucking part.
2. The cutting tool according to claim 1, wherein said shank
portion has a single helix defining a flute for ejecting
debris.
3. The cutting tool according to claim 1, wherein said shank
portion has a double helix defining a pair of flutes for ejecting
throughout debris.
4. The cutting tool according to claim 1, wherein said cutting edge
has at least two cutting edge portions, each including a rake
surface.
5. The cutting tool according to claim 1, wherein said rake face is
offset from the longitudinal axis.
6. The cutting tool according to claim 4, wherein said at least two
cutting edge portions are angled with respect to one another to
define an included angle, said included angle being in the range
from about 90.degree. to about 180.degree..
7. The cutting tool according to claim 1, wherein said cutting edge
is formed on an insert secured to said drill head.
8. The cutting tool according to claim 7, wherein said insert is
formed of carbide.
9. The cutting tool according to claim 1, wherein said rake face
angle is about 0.degree..
10. The cutting tool according to claim 1, wherein said rake face
has a ratio of length of relief to tool diameter of about 0.10 to
0.32 inches per inch diameter.
11. A cutting tool for forming a hole in concrete or the like
material, comprising: a longitudinally-extending shank portion
defining a longitudinal axis and having two ends; a chucking part
provided at one end of the shank portion; a cutting head provided
at the other end of said shank portion, a cutting edge formed on
said cutting head, said cutting edge including at least one cutting
edge portion, a rake surface formed adjacent said at least one
cutting portion, a clearance face formed adjacent said at least one
cutting portion opposing said rake face, and an edge radius between
said rake face and clearance face, said edge radius having a radius
in the range of about 0.0003 inch to 0.0040 inch.
12. The cutting tool according to claim 11, wherein said shank
portion has a single helix defining a flute for ejecting
debris.
13. The cutting tool according to claim 11, wherein said shank
portion has a double helix defining a pair of flutes for ejecting
debris.
14. The cutting tool according to claim 11, wherein said cutting
edge has at least two cutting edge portions, each including a rake
surface.
15. The cutting tool according to claim 11, wherein said rake face
is offset from the longitudinal axis.
16. The cutting tool according to claim 14, wherein said at least
two cutting edge portions are angled with respect to one another to
define an included angle, said included angle being in the range
from about 90.degree. to about 180.degree..
17. The cutting tool according to claim 11, wherein said cutting
edge is formed on an insert secured to said cutting head.
18. The cutting tool according to claim 17, wherein said insert is
formed of carbide.
19. The cutting tool according to claim 11, wherein said rake angle
is at an angle of about 0.degree..
20. The cutting tool according to claim 11, wherein said clearance
face is at an angle of about 30.degree. to about 40.degree..
21. The cutting tool according to claim 11, wherein said edge
radius is preferably from about 0.0005 inch to about 0.001
inch.
22. A cutting tool for forming a hole in concrete or the like
material, comprising: a longitudinally extending shank portion
defining a longitudinal axis and having two ends; a chucking part
provided at one end of the shank portion; a cutting head provided
at the other end of said shank portion; a cutting edge formed on
said cutting head, said cutting edge having at least one cutting
edge portion; a rake surface formed on said cutting head adjacent
said at least one cutting edge portion; and a clearance surface on
said cutting head adjacent said at least one cutting portion
opposing said rake face such that at least one of said rake and
clearance surfaces is worked to define said at least one cutting
edge portion.
23. The cutting tool according to claim 22, wherein said shank
portion has a single helix defining a flute for ejecting
debris.
24. The cutting tool according to claim 22, wherein said shank
portion has a double helix defining a pair of flutes for ejecting
debris.
25. The cutting tool according to claim 22, wherein said cutting
edge has at least two cutting edge portions, each including a rake
and clearance surface.
26. The cutting tool according to claim 22, wherein said rake face
is offset from the longitudinal axis.
27. The cutting tool according to claim 25, wherein said at least
two cutting edge portions are angled with respect to one another to
define an included angle, said included angle being in the range
from about 90.degree. to about 180.degree..
28. The cutting tool according to claim 22, wherein said cutting
edge is formed on an insert secured to said drill head.
29. The cutting tool according to claim 28, wherein said insert is
formed of carbide.
30. The cutting tool according to claim 22, wherein said rake
surface is ground into said cutting head and is at an angle in the
range of about 10.degree. to about -10.degree..
31. The cutting tool according to claim 30, wherein said clearance
surface is ground into said cutting head and is at an angle ranging
from about 10.degree. to about 50.degree..
32. The cutting tool according to claim 22, wherein said rake
surface includes a predetermined length of relief.
33. A cutting tool for forming a hole in concrete or the like
material, comprising: a longitudinally extending shank portion
defining a longitudinal axis and having two ends; a chucking part
provided at one end of the shank portion; a cutting head provided
at the other end of said shank portion; a cutting edge on said
cutting head, said cutting edge including at least one cutting edge
portion; a rake face formed adjacent said at least one cutting edge
portion; and a first egress surface formed immediately adjacent
said rake surface, such that said first egress surface, rake face
and at least one cutting edge portion define a stepped cutting
edge.
34. The cutting tool according to claim 33, wherein said shank
portion has a single helix defining a flute for ejecting
debris.
35. The cutting tool according to claim 33, wherein said shank
portion has a double helix defining a pair of flutes for ejecting
debris.
36. The cutting tool according to claim 33, wherein said cutting
edge has at least two cutting edge portions, each including a rake
surface.
37. The cutting tool according to claim 33, wherein said rake face
is offset from the longitudinal axis.
38. The cutting tool according to claim 36, wherein said at least
two cutting edge portions are angled with respect to one another to
define an included angle, said included angle being in the range
from about 90.degree. to about 180.degree..
39. The cutting tool according to claim 33, wherein said cutting
edge is formed on an insert secured to said cutting head.
40. The cutting tool according to claim 39, wherein said insert is
formed of carbide.
41. The cutting tool according to claim 33, wherein said first
egress is formed on said insert.
42. The cutting tool according to claim 33, wherein an egress area
is adjacent said first egress surface.
43. The cutting tool according to claim 33, wherein said first
egress face is at an angle in the range of about 30.degree. to
about 90.degree..
44. The cutting tool according to claim 33, wherein said first
egress surface is an arcuate surface.
45. A cutting tool for forming a hole in concrete or the like
material, comprising: a longitudinally extending shank portion
defining a longitudinal axis and having two ends; a chucking part
provided at one end of the shank portion; a cutting head provided
at the other end of said shank portion; a cutting edge on said
cutting head, said cutting edge including at least one cutting edge
portion; a rake surface formed adjacent said at least one cutting
edge portion, said rake surface including a length of relief, the
ratio of the depth of said length of relief to tool diameter being
about 0.10 to 0.32 inches per inch diameter of said tool.
46. The cutting tool according to claim 45, wherein said shank
portion has a single helix defining a flute for ejecting
debris.
47. The cutting tool according to claim 45, wherein said shank
portion has a double helix defining a pair of flutes for ejecting
debris.
48. The cutting tool according to claim 45, wherein said cutting
edge has at least two cutting edge portions, each including a rake
surface.
49. The cutting tool according to claim 45, wherein said rake
surface is offset from the longitudinal axis.
50. The cutting tool according to claim 48, wherein said cutting
edge portions are angled with respect to one another to define an
included angle, said included angle being in the range from about
90.degree. to about 180.degree..
51. The cutting tool according to claim 45, wherein said cutting
edge is formed on an insert secured to said cutting head.
52. The cutting tool according to claim 51, wherein said insert is
formed of carbide.
53. The cutting tool according to claim 45, wherein said length of
relief ratio is about 0.15 to 0.27 inches per inch diameter.
54. The cutting tool according to claim 45, wherein said rake
surface is at an angle of from about 10.degree. to about
-10.degree..
55. The cutting tool according to claim 45, wherein the rake
surface is at a positive rake angle.
56. A cutting tool or concrete, aggregate or the like material,
comprising: a longitudinally extending shank portion defining a
longitudinal axis and having two ends; a chucking part provided at
one end of the shank portion; a cutting head provided at the other
end of said shank portion, a cutting edge formed on said cutting
edge, said cutting edge having at least one cutting edge portion; a
reference plane, which is parallel to a centerline of said cutting
tool and through said cutting edge when said cutting edge is viewed
as a point; a rake surface formed adjacent said cutting edge, and
said rake surface being at a positive rake angle such that positive
angles are defined by clockwise rotation about a point on the
cutting edge portion from said reference plane at said cutting edge
to said rake face, when viewed along said cutting edge from an
outside diameter of said cutting tool, and measured in an area
between said cutting edge and said chucking part.
57. A method of forming a hole in concrete, aggregate or the like
material, comprising the steps of: providing a cutting tool
including a longitudinally extending shank portion defining a
longitudinal axis and having two ends, a chucking part provided at
one end of the shank portion, a cutting head provided at the other
end of said shank portion, a cutting edge on said drilling head,
said cutting edge having at least one cutting edge portion, a
reference plane, which is parallel to a centerline of said cutting
tool and through said cutting edge when said cutting edge is viewed
as a point a rake surface formed adjacent said cutting edge
portion, said rake face being at a rake angle in the range of about
-10.degree. to about 10.degree. such that positive angles are
defined by clockwise rotation about a point on the cutting edge
portion from said reference plane at said cutting edge to said rake
face, when viewed along said cutting edge from an outside diameter
of said cutting tool, and negative rake angles are defined by
counterclockwise rotation about said point on said cutting edge
from said reference plane to said rake face, when viewed along said
cutting edge from the outside diameter of said cutting tool and
measured in an area between said cutting edge and said chucking
part; contacting said cutting edge with the material; rotating said
cutting tool to cut said material; and thereby forming a hole in
said material.
58. The method of claim 57, further including the step of applying
a force along said longitudinal axis of said cutting tool.
59. The method of claim 58, wherein said force is constant.
60. The method of claim 58, wherein said force is sequentially
repetitious to impact the material to chisel the material.
61. A method of forming a hole in concrete, aggregate or the like
material, comprising the steps of: providing a cutting tool
including a longitudinally extending shank portion defining a
longitudinal axis and having two ends, a chucking part provided at
one end of the shank portion, a cutting head provided at the other
end of said shank portion, a cutting edge on said drilling head,
said cutting edge having at least one cutting edge portion, a rake
surface formed adjacent said cutting edge portion, a reference
plane, which is parallel to a centerline of said cutting tool and
through said cutting edge when said cutting edge is viewed as a
point said rake face being at a rake angle from about -10.degree.
to about 10.degree. such that positive angles are defined by
clockwise rotation about a point on the cutting edge portion from
said reference plane at said cutting edge to said rake face, when
viewed along said cutting edge from an outside diameter of said
cutting tool, and negative rake angles are defined by
counterclockwise rotation about said point on said cutting edge
from said reference plane to said rake face, when viewed along said
cutting edge from the outside diameter of said cutting tool and
measured in an area between said cutting edge and said chucking
part; contacting said cutting edge with the material; repeatedly
impacting said cutting tool to chisel said material; and thereby
forming a hole in said material.
62. The method of claim 61, further including the step of rotating
said cutting tool to cut the material.
63. A method of forming a hole in concrete, aggregate or the like
material, comprising the steps of: providing a cutting tool
including a longitudinally extending shank portion defining a
longitudinal axis and having two ends, a chucking part provided at
one end of the shank portion, a cutting head provided at the other
end of said shank portion, a cutting edge on said cutting head,
said cutting edge including at least one cutting edge portion, a
rake surface formed adjacent said at least one cutting portion, a
clearance face formed adjacent said at least one cutting portion
opposing said rake face, and an edge radius between said rake face
and clearance face, said edge radius being in the range from about
0.0003 to 0.0040 inch; contacting said cutting edge with the
material; rotating said cutting tool to cut said material; and
thereby forming a hole in said material.
64. The method of claim 63, further including the step of applying
a force along said longitudinal axis of said cutting tool.
65. The method of claim 64, wherein said force is constant.
66. The method of claim 64, wherein the step of applying said force
includes applying said force is sequentially repetitiously to
impact and thereby chisel the material.
67. A method of forming a hole in concrete, aggregate or the like
material, comprising the steps of: providing a cutting tool
including a longitudinally extending shank portion defining a
longitudinal axis and having two ends, a chucking part provided at
one end of the shank portion, a cutting head provided at the other
end of said shank portion, a cutting edge on said cutting head,
said cutting edge including at least one cutting edge portion, a
rake surface formed adjacent said at least one cutting portion, a
clearance face formed adjacent said at least one cutting portion
opposing said rake face, and an edge radius between said rake face
and clearance face, said edge radius having a radius of from about
0.0003 to 0.0040 inch; contacting said cutting edge with the
material; impacting said cutting tool to chisel said material; and
thereby forming a hole in said material.
68. The method of claim 67, further including the step of rotating
said cutting tool to cut the material.
69. A method of forming a hole in concrete, aggregate or the like
material, comprising the step of: providing a cutting tool
including a longitudinally extending shank portion defining a
longitudinal axis and having two ends, a chucking part provided at
one end of the shank portion, a cutting head provided at the other
end of said shank portion; a cutting edge on said cutting head,
said cutting edge including at least one cutting edge portion, a
rake surface on said cutting head adjacent said at least one
cutting edge portion, a clearance surface on said cutting head
adjacent said at least one cutting portion opposing said rake face
such that said at least one rake and clearance surfaces are worked
to define said at least one cutting edge portion; contacting said
cutting edge with the material; rotating said cutting tool to cut
said material; and thereby forming a hole in said material.
70. The method of claim 69, further including the step of applying
a force along said longitudinal axis of said cutting tool.
71. The method of claim 70, wherein said force is constant.
72. The method of claim 70, wherein the step of applying said force
includes applying said force sequentially repetitiously to impact
and thereby chisel the material.
73. A method of forming a hole in concrete, aggregate or the like
material, comprising the steps of: providing a cutting tool
including a longitudinally extending shank portion defining a
longitudinal axis and having two ends, a chucking part provided at
one end of the shank portion, a cutting head provided at the other
end of said shank portion, a cutting edge on said cutting head,
said cutting edge including cutting edge portion, a rake surface on
said cutting head adjacent said at least one cutting edge portion,
a clearance surface on said opposing cutting head adjacent said at
least one cutting portion opposing said rake face such that at
least one of said rake and clearance surfaces are worked to define
said at least one cutting edge portion; contacting said cutting
edge with the material; impacting said cutting tool to chisel said
material; and thereby forming a hole in said material.
74. The method of claim 73, further including the step of rotating
said cutting tool to cut the material.
75. A method of forming a hole in concrete, aggregate or the like
material, comprising the step of: providing a cutting tool
including a longitudinally extending shank portion defining a
longitudinal axis and having two ends, a chucking part provided at
one end of the shank portion, a cutting head provided at the other
end of said shank portion, a cutting edge on said cutting head,
said cutting edge including at least one cutting edge portion, a
rake face formed adjacent said at least one cutting edge portion, a
first egress surface formed immediately adjacent said rake surface,
such that said first egress surface, rake face and at least one
cutting edge portion define a stepped cutting edge; contacting said
cutting edge with the material; rotating said cutting tool to cut
said material; and thereby forming a hole in said material.
76. The method of claim 75, further including the step of applying
a force along said longitudinal axis of said cutting tool.
77. The method of claim 76, wherein said force is constant.
78. The method of claim 76, wherein said step of applying the force
includes impacting the material sequentially repetitiously to
chisel the material.
79. A method of forming a hole in concrete, aggregate or the like
material, comprising the steps of: providing a cutting tool
including a longitudinally extending shank portion defining a
longitudinal axis and having two ends, a chucking part provided at
one end of the shank portion, a cutting head provided at the other
end of said shank portion, a cutting edge on said cutting head,
said cutting edge including at least one cutting edge portion, a
rake face formed adjacent said at least one cutting edge portions,
a first egress surface formed immediately adjacent said rake
surface, such that said first egress surface, rake face and at
least one cutting edge portion define a stepped cutting edge;
contacting said cutting edge with the material; impacting said
cutting tool to chisel said material; and thereby forming a hole in
said material.
80. The method of claim 79, further including the step of rotating
said cutting tool to cut the material.
81. A method of forming a hole in concrete, aggregate or the like
material, comprising the steps of: providing a cutting tool
including a longitudinally extending shank portion defining a
longitudinal axis and having two ends, a chucking part provided at
one end of the shank portion, a cutting head provided at the other
end of said shank portion, a cutting edge on said drilling head,
said cutting edge including at least one cutting edge portion, a
rake surface formed adjacent said at least one cutting edge
portions, said rake surface including a length of relief, the ratio
of the depth of said length of relief to tool diameter being in the
range from about 0.10 to about 0.32 inches per inch diameter of
said tool; contacting said cutting edge with the material; rotating
said cutting tool to cut said material; and thereby forming a hole
in said material.
82. The method of claim 81, further including the step of applying
a force to said cutting tool along said longitudinal axis of said
cutting tool.
83. The method of claim 82, wherein said force is constant.
84. The method of claim 82, further including the step of applying
said force to impact said material, sequentially and repetitiously
to chisel the material.
85. A method of forming a hole in concrete, aggregate or the like
material, comprising the step of: providing a cutting tool
including a longitudinally extending shank portion defining a
longitudinal axis and having two ends, a chucking part provided at
one end of the shank portion, a cutting head provided at the other
end of said shank portion, a cutting edge on said drilling head,
said cutting edge including at least one cutting edge portion, a
rake surface formed adjacent said at least one cutting edge
portion, said rake surface including a length of relief, the ratio
of the depth of said length of relief to tool diameter being in the
range from about 0.10 to about 0.32 inches per inch diameter of
said tool; contacting said cutting edge with the material;
impacting said cutting tool to chisel said material; and thereby
forming a hole in said material.
86. The method of claim 85, further including the step of rotating
said cutting tool to cut the material.
87. The cutting tool according to claim 11, wherein a cutting angle
is between the clearance face and rake face, said cutting angle
being in the range from about 30.degree. to about 90.degree..
88. The cutting tool according to claim 11, wherein a cutting angle
is between the clearance face and rake face, said cutting angle
being in the range of about 40.degree. to about 60.degree..
89. The cutting tool according to claim 11, wherein said clearance
angle is preferably in the range of about 10.degree. to about
50.degree..
90. The cutting tool according to claim 1, wherein said cutting
edge has a primary and secondary cutting edge portion with said
-10.degree. to 10.degree. rake angle adjacent said primary cutting
edge portion and a rake angle of from about -50.degree. to
-20.degree. adjacent said secondary cutting edge portion.
91. The cutting tool according to claim 19, wherein said cutting
edge has a primary and secondary cutting edge portion with said
0.degree. rake angle adjacent said primary cutting edge portion and
a rake angle of from about -50.degree. to -20.degree. adjacent said
secondary cutting edge portion.
92. The cutting tool according to claim 30, wherein said cutting
edge has a primary and secondary cutting edge portion with said
-10.degree. to 10.degree. rake angle adjacent said primary cutting
edge portion and a rake angle of from about -50.degree. to
-20.degree. adjacent said secondary cutting edge portion.
93. The cutting tool according to claim 54, wherein said cutting
edge has a primary and secondary cutting edge portion with said
-10.degree. to 10.degree. rake angle adjacent said primary cutting
edge portion and a rake angle of from about -50.degree. to
-20.degree. adjacent said secondary cutting edge portion.
94. A method of forming a cutting tool comprising: forming an
insert; working at least one surface of said insert to form a
sharpened edge; and securing said insert to a shank to form the
cutting tool.
95. A method of forming a hole in concrete, aggregate or the like
material, comprising the steps of: providing a cutting tool
including a shank portion with two ends, a chucking part at one end
and a cutting head at the other, a cutting edge worked into said
cutting head; rotating said cutting tool; guiding swarf along said
worked cutting edge; ejecting said swarf; and forming a hole in the
material by rotating the worked edge.
Description
BACKGROUND OF THE INVENTION
1. The present invention relates to cutting tools or drill bits,
and more particularly, to cutting tools which are used in
hammering, percussive, or rotary boring or drilling applications in
concrete, aggregate, masonry or the like material.
2. When drilling concrete, aggregate or the like materials,
generally three different types of cutting tools or bits are used.
These bits can be defined as hammer bits, percussive bits, and
rotary masonry bits. In a true hammer bit, the bit is placed into a
driver which includes a hammer which is sequentially and
repetitiously moved toward and away from the bit. This hammering
action hammers the bit. While the bit is being hammered, the bit
continues to either passively or actively rotate. Thus, this type
of cutting would be synonymous with using a chisel and hitting it
with a hammer. Also, the driver may include a rotational feature
where the bit is hammered and actively rotated.
3. In percussive drilling, the drive includes a chuck which is
associated with stepping cam surfaces on gears which are rotated
and, at the same time, moved up and down within the driver. Thus,
the entire chuck mechanism rotates and moves up and down during the
cutting process.
4. A rotary masonry bit is positioned into a driver which provides
only a rotary movement. Thus, the rotary masonry bit does not move
up and down and just rotates to cut at the concrete or
aggregate.
5. Cutting tools in these three fields require different parameters
for each type of application. In hammer and percussive bits, which
utilize a chiseling action, the tip cutting angle, which provides
tip strength, debris elimination and a cutting or rake face are a
primary concern. Likewise, in rotary masonry drilling, which uses
purely rotary movement, the cutting or rake face, debris clean out
and cutting angle are also of primary importance. However, all of
these elements are interrelated to provide an optimum cutting tool
or drill bit to drill concrete, aggregate and the like
materials.
6. Existing hammer and percussive cutting tools ordinarily include
carbide insert tips with cutting edges which have large obtuse
included angles as well as a negative rake face at large acute
angles. Thus, the tip has been utilized to chisel and rotate to
drill or bore into the concrete material. The rotary masonry bits
ordinarily use a rake face on the bit so that when it is rotated,
it will bore through the concrete material.
7. Further, when the carbide tips are formed, the carbide powder is
pressed into a mold to form the tip. This tip is inserted directly
and welded or brazed onto a tool shank. Thus, this is the art
accepted way to form current design tools or bits.
SUMMARY OF THE INVENTION
8. Accordingly, it is an object of the present invention to provide
the art with a cutting tool or bit which will reduce the time to
drill holes into concrete, aggregate or the like material and
improve the quality of the hole. The present invention has an
improved cutting tip with a rake face which is slightly negative,
zero or positive. The tip cutting angle, which is the angle between
the rake face and clearance face, is smaller than current designs
to provide better chiseling action. The debris recess of the
present invention rapidly ejects debris from the tip into the
helical flutes. A rake face on the cutting tools increases cutting
action during rotation of the cutting tools in the hole.
9. Also, the present invention works the formed carbide tip,
contrary to conventional teaching, to increase performance of the
tip in drilling concrete, aggregate, masonry or the like material.
The term "works" means the tip is ground or otherwise machined to
sharpen or form a sharpened cutting edge on the tool. Further, in a
tool with a ball head the present invention defines a larger egress
space than is conventionally taught. "Egress space" is defined as
the open volume through which debris may pass on its way from being
created, to the flute of the bit to enable fast removal of
debris.
10. In accordance with one aspect of the invention, a cutting tool
comprises a longitudinally extending shank portion which defines a
longitudinal axis and two ends. One end has a chucking part and the
other end has a cutting head. A cutting edge on the cutting head
includes at least one cutting portion. A rake surface is formed
adjacent to at least one of the cutting portions. Also, a clearance
face is formed adjacent to the at least one cutting portion
opposite the rake face. An edge radius is formed between the rake
face and the clearance face and has a radius from about 0.0005 to
0.001 inch. Likewise, a method of forming, by drilling or boring a
hole in concrete, aggregate or the like material is disclosed using
the above cutting tool. The cutting edge of the cutting tool is
placed in contact with the concrete, aggregate or the like
material. The cutting tool is rotated to form a hole in the
material. Alternately, instead of rotating the tool, the tool may
be impacted to chisel away the material to form the hole.
Optionally both rotating and impacting may be conducted
simultaneously.
11. In accordance with a second aspect of the invention, a cutting
tool includes a longitudinally extending shank with a chucking end
and a cutting head. A cutting edge is formed in the cutting head
with at least one cutting edge portion. A rake surface is formed
adjacent to at least one of the cutting portions with the rake face
at an angle of from about -10.degree. to 10.degree.. A method of
forming, by boring or drilling, a hole in concrete, aggregate or
the like material is disclosed using the above cutting tool. The
cutting edge of the cutting tool is placed in contact with the
material. The cutting tool is rotated to form a hole in the
material. Alternatively, instead of rotating the tool, the tool may
be impacted to chisel away the material to form the hole.
Optionally both rotating and impacting may be conducted
simultaneously.
12. In accordance with a third aspect of the invention, a cutting
tool includes a shank portion with a chucking end and a cutting
head. The head includes a cutting edge with at least one cutting
edge portion. A rake surface is formed adjacent to at least one
cutting edge portion. Additionally, a clearance surface is formed
adjacent to the at least one cutting portion opposite the rake
face. One or both the rake surface and clearance surface are worked
to form a sharpened edge radius. A method of forming, by boring or
drilling a hole in concrete, aggregate or the like material is
disclosed using the cutting tool. The cutting edge of the cutting
tool is placed in contact with the material. The cutting tool is
rotated to form a hole in the material. Alternatively, instead of
rotating the tool, the tool may be impacted to chisel away the
material to form the hole. Optionally both rotating and impacting
may be conducted simultaneously.
13. In accordance with a fourth aspect of the invention, a cutting
tool comprises a longitudinal shank with a chucking part at one end
and a cutting head at the other end. The cutting head includes a
cutting edge with at least one cutting edge portion. A rake surface
is formed adjacent to the at least one of the cutting edge
portions. A primary egress surface is formed immediately adjacent
the rake surface such that the rake surface and primary egress
surface define a new egress path. A method of forming, by boring or
drilling, a hole in concrete aggregate or the like material is
disclosed using this cutting tool. The cutting edge of the cutting
tool is placed in contact with the material. The cutting tool is
rotated to form a hole in the material. Alternatively, instead of
rotating the tool, the tool may be impacted to chisel away the
material to form the hole. Optionally both rotating and impacting
may be conducted simultaneously.
14. In accordance with a fifth aspect of the invention, a cutting
tool comprises a longitudinally extending shank with a chucking
part at one end and a cutting head at the other end. The cutting
head includes a cutting edge with at least one cutting edge
portion. A rake surface is formed adjacent to the at least one
cutting edge portion. The rake surface includes a worked portion
which extends from the cutting edge portion to define a length of
relief. The ratio of the depth of the length of relief to tool
diameter is in a range of about 0.10 to 0.32 inches per inch
diameter of the tool. A method of forming, by boring or drilling, a
hole into concrete, aggregate or the like material is disclosed
using the above cutting tool. The cutting edge of the cutting tool
is placed in contact with the aggregate. The cutting tool is
rotated to form a hole in the material. Alternatively, instead of
rotating the tool, the tool may be impacted to chisel away the
material to form the hole. Optionally both rotating and impacting
may be conducted simultaneously.
15. Additional objects and advantages of the invention will be
apparent from the detailed description of the preferred embodiment,
the appended claims and the accompanying drawings, or may be
learned by practice of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
16. The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate two embodiments
of the present invention and together, with the description, serve
to explain the principles of the invention. In the drawings, the
same reference numeral indicates the same parts.
17. FIG. 1 is a perspective view of a prior art cutting tool, with
a portion omitted for clarity.
18. FIG. 2 is a partial side elevational view of the cutting tool
of FIG. 1.
19. FIG. 3 is a partial side elevational view, rotated 90.degree.,
of the cutting tool of FIG. 1.
20. FIG. 4 is a top plan view of the conventional cutting tool of
FIG. 1.
21. FIG. 5 is an auxiliary view along the cutting edge of the
conventional cutting tool of FIG. 2 illustrating the rake
surface.
22. FIG. 6 is a perspective view of another prior art cutting
tool.
23. FIG. 7 is a partial side elevational view of the cutting tool
of FIG. 6.
24. FIG. 8 is a partial side elevational view, rotated 90.degree.,
of the conventional cutting tool of FIG. 6.
25. FIG. 9 is a top plan view of the conventional cutting tool of
FIG. 6.
26. FIG. 10 is an auxiliary view along the cutting edge of the
conventional cutting tool of FIG. 7 illustrating the rake
surface.
27. FIG. 10A is a partial enlarged view of the tip of FIG. 10.
28. FIG. 11 is an enlarged side elevational detail view of a
cutting edge radius of the conventional cutting tool shown by
circle 11 of FIGS. 5 and 10.
29. FIG. 12 is a perspective view of a cutting tool in accordance
with the present invention, with a portion omitted for clarity.
30. FIG. 13 is a partial side elevational view of the cutting tool
of FIG. 12.
31. FIG. 14 is a partial side elevational view, rotated 90.degree.,
of the cutting tool of FIG. 12.
32. FIG. 15 is a top plan view of the cutting tool of FIG. 12.
33. FIG. 16 is an auxiliary view along the cutting edge of the
cutting tool of FIG. 12 illustrating the rake surface.
34. FIG. 17 is a perspective view of an alternate embodiment of the
cutting of the present invention.
35. FIG. 18 is a partial side elevational view of the cutting tool
of FIG. 17.
36. FIG. 19 is a partial side elevational view, rotated 90.degree.,
of the cutting tool of FIG. 17.
37. FIG. 20 is a top plan view of the cutting tool of FIG. 17.
38. FIG. 21 is an auxiliary view along the cutting edge of the
cutting tool of FIG. 17 illustrating the rake surface.
39. FIG. 21A is a partial enlarged view of the tip of FIG. 10.
40. FIG. 22 is an enlarged side elevational detail view of the
cutting edge radius of the cutting tool shown in circle 22 of FIGS.
16 and 21.
41. FIG. 23 is a side elevational schematic view, partially in
section, of the cutting tool of FIG. 12 rotating within a
material.
42. FIG. 24 is a view like FIG. 23, but with the cutting tool
impacting or chiseling the material.
43. FIG. 25 is a partial cross section of a side plan view of the
cutting tool of FIG. 17, rotating in the material.
44. FIG. 26 is a figure like that of FIG. 25, but with the cutting
tool impacting or chiseling the material.
45. FIG. 27 is a figure like that of FIG. 25, but with the cutting
tool both rotating and impacting or chiseling the material.
46. FIG. 28 is an auxiliary view taken along the cutting edge of a
cutting tool of an alternate embodiment illustrating an arcuate
first egress surface and area.
47. FIG. 29 is a partial side elevational view of another
embodiment of a cutting tool, with an 180.degree. included
angle.
48. FIG. 30 is a side elevational view like FIG. 29, rotated
90.degree..
DESCRIPTION OF PRIOR ART DRAWINGS
49. Turning to FIGS. 1 through 11, two prior art cutting tools are
illustrated. FIGS. 1 through 5 illustrate a ball head single flute
cutting tool, while FIGS. 6 through 10 illustrate a double helix
cutting tool. FIG. 11 illustrates the cutting edge radius of both
the cutting tools.
50. When defining angle measurements, it is important to use ture
angles. "True angles" are taken by defining a reference plane
parallel to the center line of the tool and through the cutting
edge in an auxiliary view with the cutting edge as a point. See for
example, FIGS. 5, 10, 16 and 21. The rake angle, designated by
.alpha., is the angle measured from the defined reference plane to
the rake face. The clearance angle, designated by CA, is the
complement of the angle measured from the defined reference plane
to the clearance face. The cutting angle, designated by .beta., is
the angle between the clearance face and rake face. The cutting
angle .beta. for negative rake angles is
(90-CA)+.vertline..alpha..vertline., and for positive rakes angles
is (90-CA)-.vertline..alpha..vertline.. The egress angle,
designated by .lambda., is the angle from the defined reference
plane to the egress face. Positive rake and egress angles are
defined by clockwise rotation about a point on the cutting edge
from defined reference plane at the cutting edge to the rake face,
when viewed along the cutting edge from the outside diameter of the
bit. Negative rake and egress angles are defined by
counterclockwise rotation about a point on the cutting edge from
the defined reference plane to the rake face, when viewed along the
cutting edge from the outside diameter of the bit. Rake angles are
measured in the zone between the cutting edge and the chucking end
of the bit. Rake angles are measured in the area between the
cutting edge and the chucking end of the bit.
51. The conventional ball head single helix cutting tool is
designated with the reference numeral 100 and the conventional
double helix tool is designated with the reference numeral 102.
Referring to FIGS. 1 through 5, the single flute cutting tool 100
has a chucking end 104 for a hammer driver and a ball cutting head
106. The shank 108 has the single helix 110 defining a flute 112.
The flute 112 ends at the cutting head 106 at a debris channel 114.
Also, an additional debris channel 116 is cut into the opposing
side of the head, which dumps directly into the flute 112, as seen
in FIG. 3.
52. The cutting head 106 includes an insert 118, which includes a
cutting edge 120, either brazed or welded or the like into a slot
122 in the cutting head 106. The insert is formed by sintering
(placing powdered carbide into a mold and compressing it).
53. The cutting edge 120 is defined, on the insert, by rake faces
124, edge radius 125 FIG. 11, and clearance faces 126. Also, a
clearance face 127 is formed on the shank, which may be at the same
angle as clearance face 126. Ordinarily, as shown in FIG. 5, first
egress faces 128 are directly adjacent to the rake faces 124, and
egress area 129 forms the remainder of the egress portion. The
egress area 129 may be on the same angle as the rake faces 124. The
rake angle, measured with respect to the reference plane 125 is
negative and is about -30.degree. to about -40.degree.. The rake
faces 124 have a substantial negative rake angle with the exception
of some percussive and rotary-only bits which are at 0.degree.. The
first egress faces 128 lead into the debris channels 114, 116. The
edge radius 125, as can best be seen in FIG. 11, is between the
rake faces 124 and clearance faces 126 and, as can be seen, is
relatively dull and is on the order of 0.004 to 0.008 inch as
measured on some prior art examples. However, while rotary-only
bits may have 0.degree. rake angles, the edge radius is in the
mentioned range. Also, the rake face 124 and clearance face 126
define a cutting edge angle between the two surfaces. The cutting
angle is an important factor in the chiseling action and in
conventional ranges from about 45.degree. to 110.degree.. Thus,
with the negative rake angle and the dull edge radius, a
conventional cutting tool 100, 102, as it rotates, glides inside
the hole, analogous to spreading butter with a knife, smoothing
away debris within the hole. One drawback is that it requires
substantial force to initiate cutting of the hole in concrete,
aggregate or the like material.
54. Referring now to FIGS. 6 through 10, in the double helix
cutting tool 102, the chucking end 104' shown is differently from
that of the single flute cutting tool 100, a rotary or
percussive-type chucking end so that it can be illustrated. The
tool includes helixes 111 and 113 as well as flutes 115 and 117.
The debris channels 114 and 116 are formed at the end of each of
the flutes at the cutting head 106.
55. The cutting tip insert 118 is the same as that previously
described and the rake faces 124, cutting edge 120 and, clearance
surfaces 126 are identified with the same numbers. However, the
egress area 129' is different than that in the single flute design
due to less head material in the double helix design. Here, the
egress area is parallel to the rake face. Also, the debris channels
114', 116' are similar.
56. Both of these cutting tools illustrate a cutting tip having a
large obtuse included angle between the two cutting edges on the
order of 120.degree. to 130.degree.. Also, the egress angle,
ordinarily about 30.degree. to 35.degree., defining the plane of
the egress area, is relatively shallow. Likewise, the clearance
angle, ordinarily about 20.degree. to 30.degree., which defines the
plane of the clearance surfaces 126, 127 is also shallow. Also a
cutting edge angle, between the rake face and clearance face, is
ordinarily about 90.degree. to 110.degree..
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
57. Turning to FIGS. 12 through 26, embodiments of the present
invention are shown. FIGS. 12 through 16 illustrate a single helix
design, designated with the reference numeral 200, and FIGS. 17
through 21 illustrate a double helix design, designated with the
reference numeral 300, respectively.
58. The single helix cutting tool 200 includes a chucking end 204,
in this particular case illustrated as a spline for a hammer
driver. Note, however, that a percussive and/or a cylindrical
rotary end or other attachment and drive means could be used. A
cutting head 206 is at the other end of the cutting tool 200 and a
shank 208 is between the two ends. The helix 210 defines a flute
212. The flute 212 terminates at the cutting head 206 into a first
debris channel or recess 214. Likewise, a second debris channel or
recess 216 is cut into the other side of the cutting head 206
opposing the recess 214 and it dumps into flute 212 as seen in FIG.
16.
59. The cutting head 206 includes an insert 218 which includes
cutting edge 220, rake faces 224, and clearance faces 226.
Likewise, egress faces 228 are immediately adjacent the rake faces
224. In elevation, the insert 218 has an overall pentagonal shape
of a house with the cutting edge 220 defining the roof, and having
sides 230 and 232, and a base 234, which is substantially
perpendicular to the two parallel sides 230 and 232. On the other
hand, the cutting edge of the present invention could be continuous
along a straight line to provide a rectangular insert, as seen in
FIGS. 29 and 30. In this embodiment, corresponding reference
numerals are increased by 200. Thus, the cutting tool is designated
with the reference numeral 400.
60. Returning to the embodiment shown in FIGS. 12 through 16, the
insert 218 is brazed, welded or the like into the slot 222 in the
cutting head 206. The insert 218 is generally manufactured from a
carbide material, such as carbide or tungsten carbide. However,
ceramics, ceramic composites, diamond dust, metal ceramic
composites, a unitary tip homogeneous with the tool shank, or a
deposit of hard layers could be used. Also, the entire cutting tool
could be manufactured from such material or a portion thereof,
including the head 206 manufactured from such a material,
eliminating the insert 218.
61. The cutting edges 220 are defined by rake faces 224, edge
radius 240 (FIG. 22) and the clearance faces 226. The cutting edges
220 include a primary cutting edge 236 and a secondary cutting edge
238. The primary cutting edge 236 is at an acute angle with respect
to the longitudinal axis 242, while the secondary cutting edge 238
is substantially perpendicular to the longitudinal axis 242.
62. The cutting edges 220 include edge radius 240 between the rake
faces 224 and clearance faces 226 (see FIG. 22). As noted above,
the edge radius 240 defines the "sharpness" of the cutting tool. An
edge radius 240 of the present invention generally ranges from
between about 0.0003 to 0.0040 inch and preferably between 0.0005
to 0.001 inch. A desired edge radius 240 provides a desired
sharpness to enable the cutting tool to cut through the concrete,
aggregate or the like material during rotation of the cutting tool.
The edge radius is formed by working, such as by grinding or the
like, the clearance face 226 and the rake face 224.
63. The two cutting edges 220 form a tip or point 221 between them.
The included angle (IA) between the two cutting edges 220 is from
about 90.degree. to 180.degree. and preferably in the range from
about 100.degree. to 160.degree..
64. As shown, for example, in FIG. 15, the cutting edges 220 are
offset from the longitudinal axis 242 of the cutting tool 200. The
rake faces 224 are worked or ground into the insert and define rake
angles a as defined above. Generally, the rake angle .alpha. is
between about 10.degree. to -10.degree., preferably at about
0.degree. for the primary cutting edge portion 236. Thus for the
primary cutting edge portion, 236, the worked rake faces 236, are
substantially parallel to the longitudinal axis 242. On the other
hand, the rake angle is between about -50.degree. to -20.degree.,
preferably to about -40.degree., for the secondary cutting edge
portion 238.
65. The rake faces 224 are formed by working, such as grinding or
the like, both sides of the insert 218, and extend a desired
distance from the cutting edge 220. The distance or depth which the
rake faces 224 extend from the cutting edge is known as the "length
of relief". The depth of the length of relief is measured from the
cutting edge 220 along the longitudinal axis 242 to a first egress
surface 244. The length of relief of the rake faces 224 has a depth
of about 0.08 inch to about 0.25 inch for a 3/4 inch diameter bit.
Preferably, the depth is from about 0.15 to about 0.25 inch. The
length of relief can be defined as a ratio with respect to the
diameter of the tool. Thus, the length of relief ratio is about
0.10 to about 0.32 inches per inch diameter of the tool.
66. The first egress surface 244 angles from the terminus or end of
the rake surface 224. The first egress surface 244 is generally
angled with respect to the rake face 224, providing an overall
stepped cutting head, as seen in FIGS. 16 and 21. The angle of the
first egress surface 244 is from about 30.degree. to 90.degree. and
preferably about 55.degree. to 60.degree. and may be continuous
with and at the same angle as the egress area 228.
67. The clearance surface 226, which includes a portion of the
insert 218 and the cutting head 206, defines a clearance angle CA.
The clearance angle CA is defined as mentioned above. This
clearance angle is from about 10.degree. to about 50.degree. and
preferably about 20.degree. to 40.degree. for hammer and percussive
tools and from about 30.degree. to 50.degree. for rotary-only
tools.
68. A cutting edge angle .beta., as defined above and shown in FIG.
22, is defined between the clearance face 226 and rake face 224.
The cutting edge angle .beta. is from about 30.degree. to
90.degree. and preferably from about 40.degree. to 60.degree. for
the primary cutting edge portion. The cutting edge angle for the
secondary cutting edge portion varies from about 60.degree. to
120.degree., and preferably from about 80.degree. to 100.degree..
These cutting edge angles define a primary cutting edge portion
which enhances cutting edge action, while the cutting angle defined
for the secondary cutting edge portion enhances the chiseling
action of the cutting tool.
69. The egress area 228 defines an egress angle .lambda. (FIG. 16)
which is measured as mentioned above. The egress area 228 is
adjacent to the first egress surface 244. The angle is at least
0.degree. and preferably from about 30.degree. to 60.degree. for
hammer and percussive tools. The range of the egress angle for
rotaar-only tool is about -20.degree. to 90.degree. and preferably
about -20.degree. to 20.degree.. Also, the first egress surface
244' and egress area 228' may be arcuate as seen in FIG. 28. Here
they are shown on the same arc. However, they could be on different
arcs. This egress area and surface enhance the transport of debris
from the tool tip into the flute 212 of the shank 208. Thus, by
providing a desired egress angle, debris is prevented from choking
at the cutting head 206. As seen in FIGS. 12 through 16, a larger
volume of material can be removed from the ball head than the
conventional cutting tool, enabling better debris removal.
70. Turning to FIGS. 17 to 21, the difference in the head 306 in
the egress area 328 and clearance surface 326 is due to a reduced
amount of tool material present in the double helix design than is
present in the single helix design. Otherwise, the angle parameters
previously described are the same with respect to the double helix
design as they are to the single helix design. The remaining
portions of the cutting head 306 are designated with reference
numerals increased by a hundred and the description is the same as
in the first embodiment since these elements are the same. The
double helix embodiment of the present invention is shown. The
cutting tool 300 includes a chuck end 304 which is one example of a
rotary or percussive type of cutting tool end. Also, the helixes
307 and 309 and flutes 310 and 312 are different from those
previously described. The helixes 310 and 312 end at the cutting
head 306, thus enabling the debris recesses 314 and 316 to include
a larger volume of debris.
71. Turning to FIGS. 23 through 27, the cutting tools of the
present invention are illustrated in action in concrete, aggregate
or the like material, forming, by boring or drilling, a hole. When
the terms "concrete", "aggregate" "or the like" material are used,
for purposes of the present invention, they include, but are not
limited to, cap block, brick, stone, ceramic materials, concrete,
aggregate, blacktop, rock, cement, masonry or the like materials.
In drilling a hole using rotary-only motion as indicated by the
arcuate arrow (FIGS. 23 and 25), the bit of the present invention
contacts the material without imparting any percussive energy. Here
the rake face of the cutting tool forms a hole into the material.
As seen in FIGS. 23 and 25, the swarf 375 is cut away from the
material to form the hole and is directed along a path along the
debris channel and, in turn, the flute due to the rotary movement.
Alternatively, as shown in FIGS. 24 and 26, the cutting tool
contacts the concrete, aggregate or the like material and impacts
or chisels the material to form a hole as indicated by the up and
down arrows. As seen in FIGS. 24 and 26, the swarf 375 is cut away
from the material to form the hole and is randomly scattered due to
impacts of the tool. Further, the cutting tool may contact the
material, and both impacting and rotating movement, as seen by both
the arcuate and up and down arrows, may be utilized together to
form a hole as seen in FIG. 27. Here the swarf 375 is randomly
scattered and directed along the debris channel and, in turn, the
flutes due to the tool movement. Generally, in this mode both where
percussion is used, the impacting is sequential and repetitious so
that a constant repeating force is applied axially onto the cutting
tool. Also, when the cutting tool is rotating only, a constant
force may be applied to the driver.
72. To manufacture a cutting tool in accordance with the present
invention, it would be made in methods consistent with those in the
art. To provide a tip with surfaces like those disclosed,
ordinarily the rake surfaces, egress surfaces and clearance
surfaces would be ground or formed by other conventional means into
the cutting tool to form the desired surfaces with desired
angles.
73. While the above detailed description describes the preferred
embodiment of the present invention, the invention is susceptible
to modification, variation, and alteration without deviating from
the scope and fair meaning of the subjoined claims.
* * * * *