U.S. patent application number 12/816522 was filed with the patent office on 2010-12-23 for bit for use in at least one of mining, trenching and milling applications.
This patent application is currently assigned to THE SOLLAMI CO.. Invention is credited to Lane Smith, Jimmie Lee Sollami, Phillip Sollami.
Application Number | 20100320003 12/816522 |
Document ID | / |
Family ID | 43353320 |
Filed Date | 2010-12-23 |
United States Patent
Application |
20100320003 |
Kind Code |
A1 |
Sollami; Phillip ; et
al. |
December 23, 2010 |
BIT FOR USE IN AT LEAST ONE OF MINING, TRENCHING AND MILLING
APPLICATIONS
Abstract
A bit includes a body portion having a first shape, a first
length, a first end and a second end. A collar portion having a
second shape, a thickness, a first surface disposed adjacent a
second end of the body portion and a second surface forming a ledge
for seating against a surface of a rotary cutting head of a mining
machine. A shank portion, has a diameter and a second length. A
first end of the shank is secured to the second surface of the
collar portion. A groove formed around the shaft portion closely
adjacent the second end thereof. A bit tip disposed adjacent the
first end of the body portion to contact a hard surface. The bit
tip tapers to a pointed end. A connecting means is disposed in the
groove for connecting the bit to the working machine. A plurality
of fins is disposed along an outer surface of the body portion.
Inventors: |
Sollami; Phillip; (Herrin,
IL) ; Smith; Lane; (Knoxville, TN) ; Sollami;
Jimmie Lee; (Herrin, IL) |
Correspondence
Address: |
James Ray & Associates
2640 Pitcairn Road
Monroeville
PA
15146
US
|
Assignee: |
THE SOLLAMI CO.
Herrin
IL
|
Family ID: |
43353320 |
Appl. No.: |
12/816522 |
Filed: |
June 16, 2010 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
61187869 |
Jun 17, 2009 |
|
|
|
Current U.S.
Class: |
175/420.1 |
Current CPC
Class: |
E21C 35/183
20130101 |
Class at
Publication: |
175/420.1 |
International
Class: |
E21B 10/627 20060101
E21B010/627 |
Claims
1. A bit for use in at least one of a trenching, milling and mining
machine, said bit comprising: (a) a body portion formed from a
first predetermine material and having each of a first
predetermined shape, a first predetermined length, a first end and
a second end; (b) a collar portion having a second predetermined
shape, a predetermined thickness, a first surface disposed adjacent
said second end of said body portion and a second surface forming a
ledge portion for seating against a surface of a rotary cutting
head of such at least one of a trenching, milling and mining
machine; (c) a substantially cylindrical shank portion, having each
of a predetermined diameter, a second predetermined length, a first
end and a second end, a first end of said shank portion being
secured to said second surface of said collar portion; (d) a
groove, having a predetermined axial length and a predetermined
depth, formed around said shaft portion closely adjacent said
second end thereof; (e) a bit tip, formed from a second
predetermined material, disposed adjacent said first end of said
body portion adapted to contact a hard surface to accomplish
removal of such hard surface, said bit tip tapering to a
substantially pointed end; (f) a connecting means disposed in said
groove for connecting said bit to such at least one of a trenching,
milling and mining machine; and (g) a predetermined number of fins
disposed along an outer surface of said body portion about a
central axis thereof.
2. A bit, according to claim 1, wherein said fins are disposed in a
helical shape in an axial direction of said mining bit.
3. A bit, according to claim 2, wherein said fins exhibit a
predetermined degree of slope in an axial and radial direction.
4. A bit, according to claim 3, wherein said predetermined degree
of slope in said axial and radial direction is between about 1
degree and about 30 degrees.
5. A bit, according to claim 4, wherein said predetermined degree
of slope is between about 6 degrees and about 15 degrees.
6. A bit, according to claim 5, wherein said predetermined degree
of slope is between about 8 degrees and about 12 degrees.
7. A bit, according to claim 1, wherein said first predetermined
material is selected from the group consisting of iron, steel and
tungsten carbide.
8. A bit, according to claim 7, wherein said first predetermined
shape of said body portion tapers inwardly toward said central axis
from said second end thereof to said first end.
9. A bit, according to claim 8, wherein said first predetermined
length is between about 3.5 inches and about 5.00 inches.
10. A bit, according to claim 1, wherein said predetermined
diameter of said cylindrical shank portion is between about 0.75
inch and about 2.00 inches.
11. A bit, according to claim 10, wherein said predetermined
diameter of said cylindrical shank portion is between about 1.375
inches and about 1.75 inches.
12. A bit, according to claim 10, wherein said second predetermined
length is between about 3.5 inches and about 5.0 inches.
13. A bit, according to claim 1, wherein said predetermined axial
length of said groove is between about 0.25 inch and about 0.625
inch.
14. A bit, according to claim 13, wherein said predetermined depth
of said groove is between about 0.125 inch and about 0.2 inch.
15. A bit, according to claim 1, wherein an overall length of said
body portion and said shaft portion and said thickness of said
collar portion is about 7.60 inches and about 7.80 inches
16. A bit, according to claim 13, wherein said predetermined axial
length of said groove is between about 0.625 inch and about 3.00
inches.
17. A bit, according to claim 1, wherein said predetermined
material for said bit tip is selected from the group consisting of
tungsten carbide and diamond.
18. A bit, according to claim 1, wherein said second predetermined
shape of said collar portion is selected from the group consisting
of generally round, rectangular, hexagon and octagon.
19. A bit, according to claim 18, wherein a presently preferred
shape of said collar portion is generally round.
20. A bit, according to claim 1, wherein said predetermined
diameter of the cylindrical shank portion is generally between
about 1.0 inch and about 2.0 inches.
21. A bit, according to claim 20, wherein said predetermined
diameter of said cylindrical shank portion is generally between
about 1.2 inches and about 1.75 inches.
22. A bit, according to claim 1, wherein said collar portion
includes a tapered portion disposed adjacent said second surface of
said collar portion.
23. A bit, according to claim 1, wherein said fins are formed from
STOODY 101 HC hard surfacing wire.
24. A bit, according to claim 1, wherein said body portion further
includes a hard surfacing buildup between said fins closely
adjacent said first end of said body portion.
25. A bit, according to claim 1, wherein said bit tip further
includes a tapered portion behind a working forward tapered surface
thereof.
26. A bit, according to claim 25, wherein said body portion further
includes a cavity formed in said first end thereof for receiving
said tapered portion of said bit tip.
27. A bit, according to claim 1, wherein said bit tip further
includes a generally cylindrical portion disposed behind a working
forward tapered surface thereof.
28. A bit, according to claim 27, wherein said body portion further
includes a generally cylindrical cavity formed in said first end
thereof for receiving said generally cylindrical portion of said
bit tip.
29. A bit, according to claim 1, wherein each of said body portion,
said collar portion and said shaft portion are formed as a single
piece.
30. A method of manufacturing a mining bit having improved
rotational capability, said method comprising the steps of: (a)
selecting a profile for said mining bit; (b) selecting a material
said profile selected in step (a) is to be manufactured from; (c)
at least one of casting, cold heading and forging said profile
selected in step (b); (d) determining a number of fins to be
attached to an outer surface of said body portion; and (e) at least
one of manually and robotically welding said number of fins
determined in step (d) in a predetermined pattern on an outer
surface of a body portion of said mining bit at a predetermined
location.
31. A method, according to claim 30, wherein steps (a) and (b) are
be reversed.
32. A method, according to claim 30, wherein said fins are
robotically welded to said outer surface of said body portion.
33. A method, according to claim 30, wherein said number of fins is
four.
34. A method, according to claim 30, wherein said method includes
the additional step of brazing a bit tip to a working end of said
bit.
35. A method of reconditioning a used mining bit, said method
comprising the steps of: (a) examining said used mining bit to
determine suitability for reconditioning; (b) removing a
predetermined portion of a body portion of said mining bit
including a bit tip when in step (a) it is determined that said
mining bit is suitable to be reconditioned; (c) adhering a new said
predetermined portion of said body portion to a remaining portion
of said body portion left after said predetermined portion has been
removed in step (b), said new predetermined portion of said mining
bit including a new bit tip.
36. A method, according to claim 35, wherein said method includes
the additional steps of: (d) determining a number of fins to be
attached to an outer surface of said new predetermined portion of
said body portion; and (e) at least one of manually and robotically
welding said number of fins determined in step (d) in a
predetermined pattern on an outer surface of a body portion of said
mining bit at a predetermined location.
37. A method, according to claim 36, wherein said adhering is
accomplished by friction welding.
38. A method, according to claim 35, wherein said welding of said
fins to said body portion is accomplished by at least one of manual
and robotic welding.
39. A method, according to claim 38, wherein said welding of said
fins to said body portion is accomplished by robotic welding.
40. In combination with a bit holder attached to at least one of a
trenching, milling and mining machine in a position to provide a
predetermined attack angle such that a bit will rotate while in
use, the improvement comprising a bit having: (a) a body portion
formed from a first predetermine material and having each of a
first predetermined shape, a first predetermined length, a first
end and a second end; (b) a collar portion having a second
predetermined shape, a predetermined thickness, a first surface
disposed adjacent said second end of said body portion and a second
surface forming a ledge portion for seating against a surface of a
rotary cutting head of such at least one of a trenching, milling
and mining machine; (c) a substantially cylindrical shank portion,
having each of a predetermined diameter, a second predetermined
length, a first end and a second end, a first end of said shank
portion being secured to said second surface of said collar
portion; (d) a groove, having a predetermined axial length and a
predetermined depth, formed around said shaft portion closely
adjacent said second end thereof; (e) a bit tip, formed from a
second predetermined material, disposed adjacent said first end of
said body portion adapted to contact a hard surface to accomplish
removal of such hard surface, said bit tip tapering to a
substantially pointed end; (f) a connecting means disposed in said
groove for connecting said bit to such at least one of a trenching,
milling and mining machine; and (g) a predetermined number of fins
disposed along an outer surface of said body portion about a
central axis thereof.
41. The combination, according to claim 40, wherein said
predetermined attack angle is generally between about 40.0 degrees
and about 50.0 degrees.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is related to and claims priority from U.S.
Provisional Patent Application Ser. No. 61/187,869 titled, "Twisted
Fin Longwall Mining Bit" the teachings of which are incorporated
herein by reference thereto.
FIELD OF THE INVENTION
[0002] The present invention relates, in general, to bits used in
trenching, milling and mining operations and, more particularly,
this invention relates to a rotating bit and, still more
specifically, the invention relates to a bit for use in a longwall
mining machine.
BACKGROUND OF THE INVENTION
[0003] In the field of mineral mining, the practice of "longwall
mining" generally involves the grinding of minerals from along a
straight, vertically inclined wall of a natural hard surface, such
as coal, rock and a combination of coal and rock, in a mineral
mine. In performing longwall mining, a machine known as a longwall
shearer is used. A longwall shearer includes a power-driven rotary
cutting head mounted along a linear guide. The linear guide aides
in moving the rotary cutting head along the hard wall surface of
the mine such that the rotary cutting head engages the wall surface
to grind away a planar section of rock/coal from the exposed wall
of such mine. The rotary cutting head typically includes several
substantially pointed nodules or "bits" which are deployed about
the surface of the rotary cutting head. As the rotary cutting head
rotates, the bits impact the rock/coal surface and assist in
breaking apart the rock/coal surface into manageably-sized chips
which move along the surface of the rotary cutter head in the space
between the bits to be carried away for further processing.
[0004] In the grinding operations when using a longwall shearer,
repeated contact of a bit against a rock/coal surface often results
in significant wear of the bit along the portion of the bit
contacting the rock/coal surface, thereby causing the substantially
pointed shape of the bit to deteriorate. This deterioration of the
bit shape typically results in decreased efficiency of the longwall
shearer. Accordingly, the bits of a longwall shearer are typically
manufactured to be removable from the rotary cutting head for
selective replacement upon becoming worn. As a result of having to
frequently replace the bits the longwall shearer must be taken out
of production during the bit replacement process. Further, it is
often the case that to minimize production down time all of the
bits will be replaced even if certain bits may still be usable.
Obviously this practice leads to added costs being incurred.
[0005] Numerous developments have been made in the field of
longwall shearer bits for prolonging the life of the bit. To this
extent, in one prior art device, a bit having a substantially
conical shape which is substantially radially symmetrical about a
central axis is provided. The conical bit is adapted to be mounted
to the surface of the rotary cutting head such that the conical bit
is free to rotate about the central axis. In this configuration, as
rock/coal chips rush over the bit surface while rock/coal is
channeled along the rotary cutting head surface, the rock/coal
chips encourage rotation of the conical bit about the central axis,
thereby encouraging more even wearing of the conical bit about the
central axis.
[0006] In another prior art device, commonly known as a "finned
bit," a similarly conical-shaped bit is provided, and includes a
plurality of fins extending radially outwardly from the central
axis along the surface of the conical-shaped bit. As mentioned
above, rotation of the bit is driven as rock/coal chips rush over
the bit surface while the rock/coal chips are channeled along the
surface of the rotary cutting head, thereby engaging the radially
extending fins. This friction on the bit surface, (aided by water
lubrication when present) is the entire driving force for rotation
of the bit, and hopefully even bit wear about the central axis of
the bit. However, in each of the above-referenced prior art
devices, bit rotation often ranges from a nearly non-existent
haphazard event on a smooth bodied conical bit to a still less than
orderly but more efficient process on a finned bit. Finned bits are
often moved in a mostly non-directional, imprecise manner that,
though not perfect, is far better than the smooth bodied tools.
[0007] The ribbed design prior art teaches that these products can
only be produced at the same time the original body section is
made. The ribs or fins are integral parts of the whole body. The
manufacturing process is a one step process--that is when the body
is formed as a cold headed process or as an investment casting
process, the rib/fin is an extruded or shaped feature on the nose
portion of the bit body.
[0008] Additional prior art devices can be found in U.S. Pat. Nos.
7,445,294; 7,455,484; 6,846,048; 6,739,327; 6,354,771; 6,196,636;
6,019,434; 5,324,098; 5,131,725; 4,809,789; 4,065,185 reissued as
RE30,807; 3,833,264; 3,652,130; 3,476,438; 3,361,481; 2,783,038;
1,903,772; 1,550,669; D572,735; D387,072; D382,887; and D347,232.
The teachings in each of these prior art references are
incorporated herein by reference thereto.
BRIEF SUMMARY OF THE INVENTION
[0009] According to one aspect of the present invention, there is
provided a bit for use in at least one of a trenching, milling and
mining machine. The bit includes a body portion formed from a first
predetermine material and having each of a first predetermined
shape, a first predetermined length, a first end and a second end.
A collar portion having a second predetermined shape, a
predetermined thickness, a first surface disposed adjacent the
second end of the body portion and a second surface forming a ledge
portion for seating against a surface of a rotary cutting head of
such at least one of a trenching, milling and mining machine. There
is a substantially cylindrical shank portion, having each of a
predetermined diameter, a second predetermined length, a first end
and a second end. The first end of the shank portion is secured to
the second surface of the collar portion. A groove, having a
predetermined axial length and a predetermined depth, is formed
around the shank portion closely adjacent the second end thereof.
There is a bit tip, formed from a predetermined material, secured
to and adjacent the first end of the body portion adapted to
contact a hard surface to accomplish removal of such hard surface,
the bit tip tapering to a substantially pointed end. A connecting
means is disposed in the groove for connecting the bit to such at
least one of a trenching, milling and mining machine. Finally, a
predetermined number of fins are disposed, in a predetermined
pattern, along an outer surface of the body portion about a central
axis thereof.
[0010] According to a second aspect of the present invention there
is provided a method of manufacturing a bit having improved
rotational capability for use in at least one of a trenching,
milling and mining application. The method includes the steps of
selecting a profile for such bit and a material the profile
selected is to be manufactured from. Thereafter, at least one of
casting and forging the profile selected and then at least one of
manually and robotically welding a predetermined number of fins in
a predetermined pattern on an outer surface of a forward body
portion of the bit at a predetermined location.
[0011] The instant invention further provides a method of
reconditioning a used bit for use in at least one of a trenching,
milling and mining application. The method includes the steps of
examining the used bit to determine its suitability for
reconditioning and removing a predetermined forward portion of a
body portion of the bit including a bit tip when it is determined
that the bit is suitable to be reconditioned. Thereafter, adhering
a new said predetermined forward portion of such body portion to a
remaining portion of the body portion left after the predetermined
forward portion has been removed. The new predetermined portion of
the bit including a new bit tip adhered thereto.
OBJECTS OF THE PRESENT INVENTION
[0012] It is, therefore, one of the primary objects of the present
invention to provide an improved bit which allows increased
production time of at least one of a trenching, milling and mining
machine between bit changes.
[0013] A further object of the present invention is to provide a
method of manufacturing a finned mining bit.
[0014] Another object of the present invention is to provide a
twisted fin mining bit which provides substantially enhanced
rotational capability of the bit thereby enabling a longer bit
life.
[0015] Still another object of the present invention is to provide
a twisted fin mining bit which provides significantly better
shattering capability of material being mined using a longwall
mining shearer.
[0016] Yet another object of the present invention is to provide a
twisted fin mining bit which provides greater scattering of the
material being mined.
[0017] A still further object of the present invention is to
provide a twisted fin mining bit which significantly reduces the
volume of respirable dust being generated during the mining
operation.
[0018] An additional object of the present invention is to provide
a twisted fin mining bit which provides a greater degree of self
sharpening capability.
[0019] Yet still another object of the present invention is to
provide a method of reconditioning a mining bit.
[0020] In addition to the numerous objects and advantages of the
instant invention described in detail above it should be understood
that various other objects and advantages of the present invention
will become more readily apparent to those skilled in the mining
and bit manufacturing arts.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0021] FIG. 1 is a side view of a first embodiment of the twisted
fin mining bit according to the present invention;
[0022] FIG. 2 is an end view of the twisted fin mining bit
illustrated in FIG. 1;
[0023] FIG. 3 is a perspective view of a second embodiment of a
twisted fin mining bit according to the present invention;
[0024] FIG. 4 is a side view of the twisted fin mining bit
illustrated in FIG. 3;
[0025] FIG. 5 is an end view of the twisted fin mining bit
illustrated in FIG. 3;
[0026] FIG. 6 is a perspective view of a third embodiment of a
twisted fin mining bit according to the present invention;
[0027] FIG. 7 is a side view of the twisted fin mining bit
illustrated in FIG. 6;
[0028] FIG. 8 is an end view of the twisted fin longwall mining bit
illustrated in FIG. 6;
[0029] FIG. 9 is a perspective view of the twisted fin mining bit
illustrated in FIG. 6 showing the tip of the bit removed from the
bit body;
[0030] FIG. 10 is a perspective view of the twisted fin mining bit
illustrated in FIG. 6 showing the tip of the bit prior to being
inserted into the bit body;
[0031] FIG. 11 is a perspective view of the twisted fin mining bit
illustrated in FIG. 6 showing the tip of the bit partially inserted
into the bit body;
[0032] FIG. 12 is a perspective view of a third embodiment of a
twisted fin mining bit according to the present invention;
[0033] FIG. 13 is a perspective view of a fourth embodiment of a
twisted fin mining bit according to the present invention;
[0034] FIG. 14 is a perspective view of a prior art type trenching,
milling or mining bit;
[0035] FIG. 15 is a perspective view of a prior art type trenching,
milling or mining bit;
[0036] FIG. 16 is a perspective view of a prior art type trenching,
milling or mining bit;
[0037] FIG. 17 is a side elevation view of another embodiment of a
bit according to the present invention attached to a base
block;
[0038] FIG. 18 is rear view of the bit illustrated in FIG. 17;
and
[0039] FIG. 19 is a top view of the bit illustrated in FIGS. 17 and
18.
BRIEF DESCRIPTION OF VARIOUS EMBODIMENTS OF THE INVENTION
[0040] Prior to proceeding to the more detailed description of the
present invention it should be noted that identical components
having identical functions have been designated with identical
reference numerals for the sake of clarity in understanding the
invention.
[0041] Additionally, it should be noted by those skilled in the art
that as used in the present application and claims the term mining
bit is meant to include mining bits, trenching bits and milling
bits and further that although the mining bit will now be described
for use in a longwall mining shearer it can be used in various
other mining, trenching and/or milling machines.
[0042] Now referring more particularly to the drawings, FIGS. 1 and
2 illustrate a mining bit, generally designated 10, for use in a
longwall mining machine (not shown) according to a first embodiment
of the present invention. The mining bit 10 includes a body portion
12 formed from a first predetermine material and having each of a
first predetermined shape, a first predetermined length, a first
end 14 and a second end 16.
[0043] A collar portion 18 having a second predetermined shape, a
predetermined thickness, a first surface 20 disposed adjacent the
second end 16 of the body portion 12 and a second surface 22
forming a ledge portion 24 is provided for seating against a
surface of a bit holder (not shown) which is attached to a head
(not shown) of a mining machine.
[0044] The second predetermined shape of the collar portion 18 is
selected from the group consisting of generally round, rectangular,
hexagon and octagon. The presently preferred shape of the collar
member 18 is generally round.
[0045] The mining bit 10 further includes a substantially
cylindrical shank portion 26, having each of a second predetermined
length and a predetermined diameter, a first end 28 and a second
end 30. The first end 28 of the shank portion 26 is secured to the
second surface 22 of the collar portion 18.
[0046] The predetermined diameter of the cylindrical shank portion
26 is between about 1.0 inch and about 2.0 inches. The most
presently preferred range for the predetermined diameter of the
cylindrical shank portion 26 is between about 1.2 inches and about
1.75 inches. Also, the second predetermined length of the shank
portion 26 is generally between about 3.5 inches and about 5.00
inches with about 4.0 inches to about 5.0 inches being presently
preferred.
[0047] A groove 32, having a predetermined axial length and a
predetermined depth, is formed around the shank portion 26 closely
adjacent the second end 30 thereof. The predetermined axial length
of the groove 32 is generally between about 0.25 inch and about
3.00 inch and the predetermined depth of the groove 32 is between
about 0.125 inch and about 0.2 inch.
[0048] There is a bit tip 34, formed from a predetermined material,
disposed adjacent the first end 14 of the body portion 12 which is
adapted to contact a hard surface, such as coal and/or a
combination of coal and rock, to accomplish removal of the hard
surface. The bit tip 34 tapers to a substantially pointed end 36.
The predetermined material of the bit tip 34 is formed from the
group selected from the group consisting of tungsten carbide and
diamond.
[0049] A connecting means, generally designated 40 (FIG. 3), is
disposed in the groove 32 for connecting the mining bit 10 to such
mining machine.
[0050] In the presently preferred embodiment of the invention the
overall length of the bit including the body portion 12 and the
shank portion 26 and the thickness of the collar portion 18 is
between about 7.60 inches and about 7.80 inches.
[0051] There are a predetermined number of fins 42 disposed in a
helical shape along an outer surface of the body portion 12 about a
central axis 38 thereof. The fins 42 preferably exhibit a
predetermined degree of slope both axially and radially about such
central axis 38 of the body portion 12.
[0052] The predetermined degree of axial and radial slope of the
fins 42 is generally between about 1 degree and about 30 degrees. A
more preferred range is between about 6 degrees and about 15
degrees. The presently preferred range for the predetermined degree
of slope is between about 8 degrees and about 12 degrees.
[0053] The plurality of fins 42 extend generally outwardly from the
central axis 38 along the surface of the body 12 to engage a hard
surface, such as coal and/or a combination of coal and rock chips,
passing over the surface of the body 12, thereby promoting rotation
of the bit 10 about the central axis 38. The fins 22 are preferably
oriented to extend in a helical shape about the central axis 38,
along the surface of the body 12.
[0054] In one embodiment, the fins 42 are fabricated from a
material having a compressive strength greater than the compressive
strength of the body 12. In this embodiment, the fins 42 further
serve to provide structural support to the body 12, thereby
protecting the body 12 and discouraging breakage of the body 12
upon impact with a hard surface.
[0055] In this embodiment, as well as the other embodiments to be
described in detail hereinafter, the fins 42 are formed from hard
surfacing ridges, such as STOODY 101 HC hard surfacing wire.
[0056] However, those skilled in the art will recognize other
materials having suitable strength and wear resistance for use in
forming the fins 42.
[0057] The predetermined degree of axial and radial slope of the
fins 42 is generally between about 1 degree and about 30 degrees. A
more preferred range is between about 6 degrees and about 15
degrees. The presently preferred range for the predetermined degree
of slope is between about 8 degrees and about 12 degrees. Further,
in this embodiment of the invention, the first predetermined
material is selected from the group consisting of iron, steel and
tungsten carbide. Also, the first predetermined shape of the body
portion 12 tapers axially inwardly from the second end 16 thereof
toward the first end 14. The predetermined length of the body
portion 12 is generally between about 3.50 inches and about 5.00
inches. A more preferred range for the body portion 12 length is
between about 3.50 inches and about 5.00 inches.
[0058] According to a second embodiment, illustrated in FIGS. 3-5,
the collar portion 44 of a mining bit, generally designated 50,
includes a tapered portion 46 disposed adjacent the second surface
22 of collar portion 44. In this embodiment, the fins 42 are
positioned closer to the first end 14 of the body portion 12 and
terminate at a point farther away from the first surface 20 of the
collar portion 44 than in the embodiment illustrated in FIGS.
1-2.
[0059] In a third embodiment, illustrated in FIGS. 6-11, the body
portion 12 further includes a hard surfacing buildup between said
fins closely adjacent said first end of said body portion. Further,
in this embodiment the body portion 12 further includes each of a
hard surfacing buildup 48 between the fins 42 closely adjacent the
first end 14 of such body portion 12 and a cavity 52 formed in said
first end 14 thereof for receiving a tapered portion 54 of a bit
tip 34. It should also be noted that tip 34 is tapered along nearly
an entire sidewall length.
[0060] Reference is now made, more particularly, to FIGS. 12 and 13
wherein there is illustrated the fins 42 extending out to the first
end 14 of the body portion 12.
[0061] The present invention further provides a method of
manufacturing a mining bit having improved rotational capability.
The method includes the steps of selecting a profile for said
mining bit and selecting a material the profile selected in step
(a) is to be manufactured from. The method further includes the
steps of at least one of casting, cold heading and forging the
profile selected and at least one of manually and robotically
welding a predetermined number of fins in a helical pattern on an
outer surface of a body portion of the mining bit at a
predetermined location.
[0062] The distinguishing difference between the prior art designs
and method of manufacturing these designs and the new bit designs
and methods of manufacturing these new designs is that the process
for generating these features can only be done in a secondary
manufacturing operation. The rib/fin is attached by a manual
welding technique or preferably by a robotic welding process.
[0063] When robotically welding the rib/fin configuration on the
nose portion of the bit body, the design parameters become nearly
endless. For example, the axial length, height as well as length of
the rib can be the same or different on the same bit body. The
material used can be applied to match the cutting conditions. When
cutting mainly coal, a less expensive hardsurfacing material can be
used. When cutting primarily rock, a more wear resistant material
is used. We currently use Stoody 101HC hardsurfacing welding
material, or equivalent. However, a tungsten carbide impregnated
material can be applied in a hardsurfacing process. The method of
robotic welding allows greater flexibility in the choice of
hardsurfacing materials as well as application of the rib/fin
profile.
[0064] In still another embodiment of the invention there is
provided a method of reconditioning a used mining bit. The method
includes the steps of examining the used mining bit to determine
its suitability for reconditioning. Then, removing a predetermined
portion of a body portion from the front of the mining bit
including a bit tip when it is determined that the mining bit is
suitable to be reconditioned and thereafter adhering a new
predetermined portion of the body portion to a remaining portion of
such body. The new predetermined portion of the mining bit
including a new bit tip. Such adhering of the new predetermined
portion to the remaining portion of such body portion is
accomplished by friction welding.
[0065] Preferably, the method includes the additional steps of
determining a number of fins to be attached to an outer surface of
the new predetermined portion of such body portion and at least one
of manually and robotically welding the number of fins in a
predetermined pattern on an outer surface of a body portion of said
mining bit at a predetermined location. The fins are preferably
welded by a robotic welder although manually welding may be
used.
[0066] According to a final embodiment of the invention there is
provided in combination with a bit holder, generally designated 60,
attached to at least one of a trenching, milling and mining machine
(not shown) in a position to provide a predetermined attack angle
of between about 40.0 degrees and 50.0 degrees such that a bit,
generally designated 10 will rotate while in use, the improvement
comprising a bit 10 having a predetermined number of fins 42
disposed on the forward end of the body portion 12. A bit tip 34 is
disposed adjacent the first end of the body portion 12 and is
adapted to contact a hard surface to accomplish removal of such
hard surface.
[0067] While the present invention has been illustrated by
description of several embodiments and while the illustrative
embodiments have been described in detail, it is not the intention
of the applicant to restrict or in any way limit the scope of the
appended claims to such detail. Additional modifications will
readily appear to those skilled in the art. The invention in its
broader aspects is therefore not limited to the specific details,
representative apparatus and methods, and illustrative examples
shown and described. Accordingly, departures may be made from such
details without departing from the spirit or scope of applicant's
general inventive concept.
* * * * *