U.S. patent application number 14/168103 was filed with the patent office on 2015-07-30 for multiple cutters on a degradation pick.
The applicant listed for this patent is David R. Hall, Francis E. Leany. Invention is credited to David R. Hall, Francis E. Leany.
Application Number | 20150211365 14/168103 |
Document ID | / |
Family ID | 53678576 |
Filed Date | 2015-07-30 |
United States Patent
Application |
20150211365 |
Kind Code |
A1 |
Hall; David R. ; et
al. |
July 30, 2015 |
Multiple Cutters on a Degradation Pick
Abstract
A degradation pick for degrading a surface comprises a
substantially conical body with a pointed end. A shank is attached
to the substantially conical body opposite the pointed end. At
least one cutter is disposed within at least one cavity which
itself is disposed on an exterior surface of the substantially
conical body between the pointed end and the shank.
Inventors: |
Hall; David R.; (Provo,
UT) ; Leany; Francis E.; (Salem, UT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hall; David R.
Leany; Francis E. |
Provo
Salem |
UT
UT |
US
US |
|
|
Family ID: |
53678576 |
Appl. No.: |
14/168103 |
Filed: |
January 30, 2014 |
Current U.S.
Class: |
299/105 |
Current CPC
Class: |
E21C 35/1833 20200501;
E21C 35/191 20200501; E21C 35/183 20130101 |
International
Class: |
E21C 35/183 20060101
E21C035/183 |
Claims
1. A degradation pick, comprising: a substantially conical body
comprising a pointed end; a shank attached to the substantially
conical body opposite the pointed end; at least one cavity disposed
on an exterior surface of the substantially conical body between
the pointed end and the shank; and at least one cutter disposed
within the cavity.
2. The degradation pick of claim 1, wherein the at least one cutter
comprises polycrystalline diamond attached to a carbide
substrate.
3. The degradation pick of claim 2, wherein the polycrystalline
diamond comprises a substantially conical geometry.
4. The degradation pick of claim 2, wherein the polycrystalline
diamond comprises a substantially hemispherical geometry.
5. The degradation pick of claim 2, wherein the polycrystalline
diamond comprises a substantially cylindrical geometry.
6. The degradation pick of claim 2, wherein the carbide substrate
is disposed within the at least one cavity.
7. The degradation pick of claim 2, wherein the polycrystalline
diamond is disposed outside of the at least one cavity.
8. The degradation pick of claim 2, wherein the polycrystalline
diamond of the cutter protrudes from the cavity.
9. The degradation pick of claim 1, wherein the at least one cutter
comprises a central axis perpendicular to the exterior surface of
the substantially conical body.
10. The degradation pick of claim 1, wherein the at least one
cutter comprises a central axis offset from a central axis of the
substantially conical body by 5 to 85 degrees.
11. The degradation pick of claim 1, further comprising a plurality
of cutters disposed on the exterior surface of the substantially
conical body between the pointed end and the shank.
12. The degradation pick of claim 11, wherein a combination of the
plurality of cutters forms between 1 and 40% of a circumference of
the substantially conical body.
13. The degradation pick of claim 11, wherein the plurality of
cutters are equally spaced from the pointed end of the
substantially conical body.
14. The degradation pick of claim 1, further comprising a block
with a hole therein disposed on a surface of a rotatable drum,
wherein the shank of the substantially conical body is disposed
within the hole.
15. The degradation pick of claim 14, wherein the block is disposed
substantially adjacent an edge of the rotatable drum and the hole
sits at an angle offset from a line perpendicular to an axis of
rotation of the rotatable drum.
16. The degradation pick of claim 15, wherein the angle of the hole
causes the pointed end of the substantially conical body to
overhang the edge of the rotatable drum.
17. The degradation pick of claim 16, wherein the angle of the hole
causes the at least one cutter to be disposed substantially on a
line perpendicular to the axis of rotation of the rotatable drum
and passing through the edge of the rotatable drum.
18. The degradation drum of claim 14, wherein the at least one
cutter is disposed along a line perpendicular to an axis of
rotation of the rotatable drum and in a direction of rotation.
19. The degradation drum of claim 1, further comprising a cutting
element disposed on the pointed end of the substantially conical
body.
20. The degradation pick of claim 1, wherein the shank comprises a
central axis offset from a central axis of the substantially
conical body.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This patent application claims priority to U.S. Provisional
Pat. App. No. 61/758,345 which is incorporated herein by reference
for all that it contains.
BACKGROUND OF THE INVENTION
[0002] The present invention relates generally to the degradation
of natural and man-made surfaces as is common in such fields as
road milling, mining and construction. More particularly, the
present invention relates to increasing the wear resistance of
degradation picks commonly used in such processes. In road milling,
for example, degradation picks may be secured to the exterior of a
rotating drum and brought into engagement with a road surface to
remove a layer of the surface in preparation for applying a new
layer. In another example, degradation picks may be secured to
links of a chain and brought into engagement with the wall of a
mine to remove earthen materials. Such uses can wear down a
degradation pick quickly.
[0003] Degradation picks often comprise a steel body comprising an
attachment shank at one end and a super hard tip at an opposing
end. As the steel body wears it may fail prior to the super hard
tip, prematurely ending the life of the pick. Increasing the wear
resistance of degradation picks may extend the life of such picks
and thus reduce the frequency that such picks need to be replaced
during operation.
[0004] Wear to the steel body is especially pronounced on surfaces
facing a direction of impact. For example, degradation picks
secured to the exterior of a rotating drum may tend to wear on
surfaces facing the direction of rotation since these surfaces are
most likely to impact a surface. Additionally, it is known to
secure degradation picks adjacent an edge of a rotating drum at an
angle offset from a line perpendicular to an axis of rotation of
the rotatable drum. This offset may position a super hard cutter
beyond the edge of the rotating drum to clear aggregate from side
walls of a cut which have a tendency to collapse. While this offset
may provide a cleaner side wall, it may also expose an exterior of
the steel body to impact from a road surface without protection
from the super hard cutter.
[0005] Consequently, numerous attempts have been made to increase
the wear resistance of degradation picks.
[0006] One such system is disclosed in U.S. Pat. No. 4,682,987 to
Brady et al. which shows heavy duty industrial, mining and general
purpose cutting tools comprising hard surface coatings comprising
nickel-chromium metal alloy powder and a flux, usually boron and/or
silicon. The hard surface is applied in slurry form, dried and then
fused in a furnace.
[0007] Another such system is disclosed by U.S. Pat. No. 4,725,098
to Beach, which describes a rotary cutting bit for use in mining
and excavating applications incorporating an annular groove about a
head portion of the bit immediately rearwardly of where a hard tip
of the bit is seated and a hardfacing material deposited in the
groove in the form of an annular ring.
[0008] Another such system is disclosed by U.S. Pat. No. 7,300,115
to Holl et al., which describes a chisel holder for a road milling
machine or the like, having a base element supporting a holding
neck, a protrusion connected to the base element upstream of the
holding neck when viewed in an advancing direction of the tool and
a chip breaker formed on the base element and extending, starting
at the holding neck, at least partially over the protrusion.
[0009] The prior art shows some advancements in increasing the wear
resistance of degradation picks; however, it is believed that there
is still a need to develop improved wear resistance
apparatuses.
BRIEF SUMMARY OF THE INVENTION
[0010] In one aspect of the present invention, a degradation pick
for degrading a surface comprises a substantially conical body with
a pointed end. The pointed end may comprise a super hard cutting
element to increase durability. The super hard cutting element may
comprise sintered polycrystalline diamond attached to a carbide
substrate. The substrate may be attached to a bolster, and the
bolster may be attached to the pointed end of the substantially
conical body. A shank may be attached to the substantially conical
body opposite the pointed end. At least one cavity may be disposed
on an exterior surface of the substantially conical body between
the pointed end and the shank. At least one cutter, also comprising
sintered polycrystalline diamond attached to a carbide substrate,
may be disposed within the cavity.
[0011] In some embodiments, the carbide substrate portion of the at
least one cutter is disposed within the at least one cavity. The
polycrystalline diamond portion of the cutter may protrude from the
cavity. In other embodiments, the polycrystalline diamond portion
is disposed outside of the at least one cavity.
[0012] In various embodiments, the polycrystalline diamond portion
may comprise a substantially conical geometry, hemispherical
geometry or cylindrical geometry. In some embodiments, the at least
one cutter comprises a central axis perpendicular to the exterior
surface of the conical body. The central axis of the at least one
cutter may be offset from a central axis of the substantially
conical body by 5 to 85 degrees.
[0013] In some embodiments, the degradation pick further comprises
a plurality of cutters. A combination of the plurality of cutters
may form between 1 and 40% of a circumference of the substantially
conical body. The plurality of cutters may be equally spaced from
the pointed end of the substantially conical body.
[0014] In some embodiments, a block with a hole therein may be
disposed on a surface of a rotatable drum. The shank of the
substantially conical body may be disposed within the hole. The
hole may sit at an angle offset from a line perpendicular to an
axis of rotation of the rotatable drum and the block may be
disposed substantially adjacent an edge of the rotatable drum. The
angle of the hole may cause the pointed end of the substantially
conical body to overhang the edge of the rotatable drum. The angle
of the hole may also cause the at least one cutter to be disposed
substantially on a line perpendicular to the axis of rotation of
the rotatable drum and passing through the edge of the rotatable
drum. The at least one cutter may be disposed along a line
perpendicular to an axis of rotation of the rotatable drum and in a
direction of rotation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a magnified orthogonal view of an embodiment of a
degradation pick of the present invention secured to an exterior of
a rotatable drum.
[0016] FIG. 2 is a perspective view of an embodiment of a
degradation pick of the present invention.
[0017] FIGS. 3a and 3b are longitudinal section views of other
embodiments of degradation picks comprising at least one cutter
disposed within at least one cavity.
[0018] FIGS. 4a, 4b and 4c are perspective views of embodiments of
degradation picks comprising various cutter geometries.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Referring now to the figures, FIG. 1 discloses a front
orthogonal view of a rotatable drum 100 such as may be used in road
milling, mining or construction. A plurality of blocks 110, each
comprising a hole 115 therein, may be disposed around an exterior
surface of the rotatable drum 100. A plurality of degradation picks
120, each comprising a substantially conical body 125 comprising a
pointed end 130 opposite a shank (hidden), may be secured to the
plurality of blocks 110 by disposing each shank within a hole 115.
The rotatable drum 100 may be rotated to bring a super hard tip 135
disposed on the pointed end 130 into contact with and degrade a
surface.
[0020] While the plurality of blocks 110 are generally positioned
such that the pointed end 130 may face in a direction of rotation,
it is known to position blocks substantially adjacent an edge of a
rotatable drum at an angle offset from a line perpendicular to an
axis of rotation of the rotatable drum. This configuration, which
is shown in the magnified view of FIG. 1, may position the hole
such that the pointed end 130 overhangs the edge of the rotatable
drum 100. By allowing the pointed end 130 to overhang the edge of
the rotatable drum 100, the super hard tip 135 may act to clear
aggregate from side walls of a cut which have a tendency to
collapse. However, while this offset may provide a cleaner side
wall, it may also expose an exterior of the substantially conical
body 125 to impact from a road surface without protection from the
super hard tip 135.
[0021] The substantially conical body 125 may be made of steel and
consequently wear at a faster rate than the super hard tip 135.
This may prematurely limit the useful life of a degradation pick
because significant wear may not have occurred at the super hard
tip 135 when the steel is in need of replacement. To offset
extensive wear to the substantially conical body 125 and thus
extend the useful life of a degradation pick, at least one cutter
160 may be disposed within a cavity on an exterior surface of the
substantially conical body 125.
[0022] Embodiments of the present invention may position the at
least one cutter 160 substantially on a line perpendicular to an
axis of rotation of the rotatable drum 100, passing through the
edge of the rotatable drum 100 and/or in a direction of
rotation.
[0023] FIG. 2 discloses an embodiment of a degradation pick 200 of
the present invention for degrading surfaces. The degradation pick
200 shown comprises a substantially conical body 205 with a pointed
end 210. The pointed end 210 may comprise a super hard cutting
element 215 to increase the durability of the pointed end 210 of
the substantially conical body 205. The super hard cutting element
215 may comprise sintered polycrystalline diamond 220 attached to a
carbide substrate 225. The carbide substrate 225 may be attached to
a bolster 230, and the bolster 230 may be attached to the pointed
end 210 of the substantially conical body 205.
[0024] The degradation pick 200 further comprises a shank 240
attached to the substantially conical body 205 opposite the pointed
end 210. In the embodiment shown, the shank 240 comprises a
substantially circular cross-section. However, in other various
embodiments, the shank may also comprise a substantially polygonal
cross-section or asymmetrical cross-section.
[0025] FIG. 3a discloses another embodiment of a degradation pick
300a comprising at least one cavity 350a disposed on an exterior
surface 355a of a substantially conical body 305a between a pointed
end 310a and a shank 340a. At least one cutter 360a is disposed
within the at least one cavity 350a. As shown in the figure, a
central axis of the at least one cutter 360a may be perpendicular
to the exterior surface 355a of the substantially conical body
305a. As is also shown in the figure, the central axis of the at
least one cutter 360a may also be offset from a central axis of the
substantially conical body 305a by 5 to 85 degrees. In this
formation, the at least one cutter 360a may shield the
substantially conical body 305a from wear during a surface
degradation operation. The at least one cutter 360a may be
removable and replaceable to prolong the life of the degradation
pick.
[0026] The at least one cutter 360a may comprise polycrystalline
diamond 362a attached to a carbide substrate 367a. The carbide
substrate 367a may be disposed within the at least one cavity 350a.
In various embodiments, the carbide substrate 367a may be brazed or
press-fit within the at least one cavity 350a.
[0027] In the embodiment shown, the polycrystalline diamond 362a is
protruding from the at least one cavity 350a such that the carbide
substrate 367a is completely disposed inside the at least one
cavity 350a.
[0028] FIG. 3b discloses yet another embodiment of a degradation
pick 300b comprising at least one cutter 360b disposed within at
least one cavity 350b. In the embodiment shown, polycrystalline
diamond 362b forming part of the at least one cutter 360b is
completely disposed outside of at least one cavity 350b.
[0029] FIGS. 4a, 4b and 4c disclose various embodiments of
degradation picks 400a, 400b and 400c each comprising a plurality
of cutters 460a, 460b and 460c disposed within cavities thereon.
While FIGS. 4a, 4b and 4c show each degradation pick comprising two
cutters equally spaced from the pointed end of a substantially
conical body, it is anticipated that any number of cutters may be
used. In embodiments where a plurality of cutters is employed, a
combination of the plurality of cutters may make up between 1 and
40% of a circumference of the substantially conical body. Each of
the plurality of cutters 460a, 460b and 460c may comprise
polycrystalline diamond protruding from the cavities.
[0030] As shown, the polycrystalline diamond may comprise a
substantially hemispherical geometry (as shown in FIG. 4a), a
substantially cylindrical geometry (as shown in FIG. 4b), or a
substantially conical geometry (as shown in FIG. 4c). Also, in the
embodiments shown, the shank comprises a central axis offset from a
central axis of a substantially conical body.
[0031] Whereas the present invention has been described in
particular relation to the drawings attached hereto, it should be
understood that other and further modifications apart from those
shown or suggested herein, may be made within the scope and spirit
of the present invention.
* * * * *