Note: Descriptions are shown in the official language in which they were submitted.
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TREE STUMP REMOVAL DEVICE
FIELD OF THE INVENTION
[0001] The present invention relates generally to tree stump removal devices.
It
relates more particularly to a tree stump removal device that severs the
surrounding root system from a stump.
BACKGROUND OF THE INVENTION
[0002] It has long been a problem to remove the remaining tree stump from the
ground once the tree trunk has been severed there from. This problem exists
for
both professional tree services including orchardists, foresters and
landscapers as
well as the everyday homeowner. Present stump removal methods are costly and
most often remove the tree stump without removing the roots. Another
disadvantage of present methods is that they often disturb a large area of
soil
around the tree stump.
[0003] The present disclosure is directed to overcoming one or more of the
problems set forth above.
SUMMARY OF THE INVENTION
[0004] The present disclosure relates to a tree stump removal device including
a
tubular body having a predetermined length extending from a first end to a
second
end, a cap attached to the first end, and cutters connected to the second end
of the
tubular body. The cutters may be integral with the second end of the tubular
body
or may be mechanically attached to the second end of the tubular body. The cap
includes a releasable coupling that can be attached to a power rotational
device to
operate the tree stump removal device.
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[0005] The present disclosure further relates to a tree stump removal device
including a tapered tubular
body comprising a length extending from a first end to a second end, a cap
removably attached to the first
end, and cutters connected to the second end.
[0006] The present disclosure further relates to a method of tree stump
removal including cutting a
circular slot with a tree stump removal device around a tree stump to a
predetermined depth into ground
around the tree stump.
[0007] One advantage of the present disclosure is to provide an improved tree
stump removal device that
severs all or some of the roots horizontally extending from the tree stump.
[0008] Another advantage of the present disclosure is to provide a tree stump
removal device that is
simple to operate and economical to manufacture.
[0008A] In a broad aspect, the invention pertains to a stump removal device
for removal of a tree stump
from the ground and severing roots from the tree stump prior to removal of the
tree stump from the
ground. A tubular body comprises a predetermined length extending from a first
end to a second end and
is adapted to fit over at least a portion of the tree stump. There is provided
a cap having a top and a
bottom, the cap being attached to the first end and including releasable power
take-off coupling extending
vertically from the top of the cap and having a recess adapted to receive a
power rotational device for
rotating the tubular body. The coupling further includes an opening through
the coupling that traverses
the recess. The second end has one or more cutters connected to the second end
of the tubular body
adapted to cut into the ground around at least a portion of the tree stump,
severing roots from the tree
stump, and the second end of the tubular body includes one or more notches
adapted to receive the one or
more cutters.
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[0008B] In a further aspect, the invention embodies a method of removing a
tree stump, comprising
providing a tree stump removal device. The device further comprises a tubular
body comprising a
predetermined length extending from a first end to a second end and adapted to
fit over at least a portion
of the tree stump. A cap has a top and a bottom, the cap being attached to the
first end. The cap includes
a releasable power take-off coupling extending vertically from the top of the
cap and having a recess
adapted to receive a power rotational device for rotating the tubular body.
The coupling further includes
an opening through the coupling that traverses the recess. The second end has
one or more cutters
connected to the second end of the tubular body and is adapted to cut into the
ground around at least a
portion of the tree stump for severing roots from the tree stump, and the
second end of the tubular body
includes one or more notches adapted to receive the one or more cutters. There
is provided a power
rotational device, the power rotational device being attached to the coupling.
The tree stump removal
device is aligned over at least a portion of the tree stump so that the tree
stump removal device overlaps
both the tree stump and at least soil or debris adjacent to the tree stump.
The tree stump removal device
cuts a circular slot around the tree stump and into the adjacent soil or
debris adjacent the tree stump by
applying power to the tree stump removal device, and lowering the tree stump
removal device to a
predetermined depth into ground around the tree stump, and removing the tree
stump removal device
from the ground.
[0009] Other features and advantages of the present invention will be apparent
from the following more
detailed description of the preferred embodiment, taken in conjunction with
the accompanying drawings
which illustrate, by way of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Fig. 1 is a perspective view of an exemplary embodiment of a tree stump
removal device.
[0011] Fig. 2A is a perspective view of another embodiment of a tree stump
removal device shown
disassembled.
[0012] Fig. 2B is a perspective view of the tree stump removal device shown in
Fig. 2A disassembled.
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[0013] Fig. 3A is a perspective view of another embodiment of a tree stump
removal device shown disassembled.
[0014] Fig. 3B is a perspective view of a partial section of Fig. 3A.
[0015] Fig. 4A is a perspective view of another embodiment of a tree stump
removal device according to the invention.
[0016] Fig. 4B is a partial perspective view of a bottom portion of the tree
stump
removal device of Fig. 4A.
[0017] Fig. 4C is a partial sectional view of a bottom portion of the tree
stump
removal device of Fig. 4A.
[0018] Fig. 4D is a partial perspective view of a bottom portion of another
embodiment of a tree stump removal device according to the invention.
[0019] Figure 5A depicts an embodiment of the present invention depicting a
cutter portion body with notches for accepting a cutter assembly.
[0020] Figure 5B depicts a bottom view of the cutter portion body of Figure 5A
viewed from the bottom.
[0021] Figure 6A depicts a side view of a cutter holder as part of the cutter
assembly.
[0022] Figure 6B depicts a front view of the cutter holder of Figure 6A.
[0023] Figure 7 depicts a cutter insert as part of the cutter assembly.
[0024] Figure 8 depicts a cutter assembly comprising the cutter insert
assembled to
the cutter holder to form a cutter assembly and the cutter assembly assembled
to
the cutter portion body of the tree stump removal device.
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[0025] Figure 9 represents a method for removing a tree stump having a
diameter
larger than the diameter of the tree stump removal device according to the
invention.
[0026] Wherever possible, the same reference numbers will be used throughout
the
drawings to refer to the same or like parts.
DETAILED DESCRIPTION OF THE INVENTION
[0027] Fig. 1 shows an exemplary embodiment of a tree stump removal device 100
according to the invention. As can be seen in Fig. 1, the tree stump removal
device
=
100 includes a body portion 110 and a top portion or cap 120. The body portion
110 includes a housing portion 111 and a cutting portion 112.
[0028] The housing portion 111 may have a generally tapered tubular shape
having a length L extending from a top end 113 to a bottom end 114. The
housing
portion 111 has a first outside diameter OD1 at the top end 113 and a second
outside diameter 0D2 at the bottom end. The housing portion 111 further has a
first inside diameter ID I at the top end and a second inside diameter ID2 at
the
bottom end 114. ID1 is greater than ID2. The change in diameter from ID1 to
ID2
is proportional to L. In one embodiment, the ratio of decreasing diameter to
length
is between about 0.125:12 to about 2.0:12. In another embodiment, the ratio of
decreasing diameter to length is between about 0.25:12 to about 1.0:12. In yet
another embodiment, the ratio of decreasing diameter to length is between
about
0.5:12 to about 0.75:12. In yet another embodiment, the housing portion 111
may
have a constant internal diameter over L. In yet another embodiment, the
housing
portion 111 may have a discontinuous internal diameter over L. The housing
portion 111 may be formed of a metal, metal alloy or composite, such as, but
limited to ferrous or nonferrous metals, and composites, such as, but not
limited to
a steel or aluminum alloy.
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[0029] The housing portion 111 further includes tabs 115. The tabs 115 include
openings 116 for receiving fasteners 117. In this exemplary embodiment, the
tabs
115 are joined to the housing portion 111. The tabs 115 may be joined to the
housing portion 111 by brazing, welding or other metal joining technique. In
another embodiment, the tabs 115 may be an integral part of the housing
portion
111. As used herein, the term "integral part" and "integral to" means that the
portion is a part of the initial forming of the part. In yet another
embodiment, the
housing portion 111 does not include tabs 115, and the openings 116 are
integral to
the housing portion 111. The housing portion 111 includes three tabs 115. In
another embodiment, the housing portion 111 may include two or more tabs 115.
The fasteners 117 may be, but is not limited to, pin, bolts, screws or other
similar
devices.
[0030] The cutting portion 112 is fixed to the housing portion 111. The
cutting
portion 112 includes a cutting portion body 112a and cutters 118. The cutting
portion 112a may be fixed to the housing portion 111 by a metal joining
technique,
such as, but not limited to brazing and welding. In another embodiment, the
cutting
portion 112a may be integral to the housing portion 111. The cutting portion
112
may be formed of the same or different material as the main portion 114. The
cutting portion 112 has a same or approximately the same second inside
diameter
ID2 as the housing portion 111 at bottom end 114 of the housing portion 111.
[0031] In this exemplary embodiment, cutters 118 may be cutting teeth formed
into the cutting portion body 112a. The cutters 118 may be integrally formed
into
the cutting portion 112 by cutting, grinding, machining or other metal forming
method. In another embodiment, cutters 118 may be projections, inserts,
attachments, or other frictional devices formed as an integral part of the
cutting
portion body 112a. In yet another embodiment, the cutters may be mechanically
fastened to the cutting portion body 112a. In still another embodiment, the
cutters
may be integrally attached to the cutting portion body 112a by metallurgically
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joining the cutting portion to the cutting portion body 112a. For example, a
cutting
portion may be metallurgically joined by welding a separate cutting insert to
the
cutting portion body 112a. Alternatively, the cutting portion also may be
provided
metallurgically by hard facing projections in the cutting portion body with a
wear
resistant hard facing material such as stellite. In an embodiment, cutters 118
may
be joined to the cutting portion body 112a by a material joining technique,
such as,
but not limited to brazing or welding.
[0032] In one embodiment, the cutters 118 are directional, or in other words,
pitched to cut in a particular rotational direction R of the tree stump
removal
device 100. In another embodiment, the cutters 118 may be bi-directional.
[0033] The cutters 118 include a cutting face or surface 118a. In one
exemplary
embodiment, the cutting surface 118a is the exposed surface of the cutters
118. In
another embodiment, the cutting surface 118a may be hardfaced with an
appropriate hardfacing material. In another embodiment, the cutting surface
118a
be a surface of an insert, bit, or other attachment, that is attached,
mechanically
fastened or otherwise joined to the cutters 118.
[0034] The cap 120 includes a cap body 120a and a coupling 130. The cap body
120a may include optional openings (not show, but shown as 460 in Fig. 4). The
cap 120 is capable of joining to the housing portion 111. The cap 120 has an
outside diameter 0D3. In this exemplary embodiment 0D3 is approximately equal
to OD1. In another embodiment, 0D3 may be larger or smaller than OD1. For
example, 0D3 may be approximately equal to ID 1. The cap 120 includes cap tabs
115A that correspond to tabs 115. The cap tabs 115A have openings 116A that
correspond to openings 116. In one embodiment, the openings 116a may be
threaded. In such a manner openings 116 and 116A are aligned when the cap 120
is joined to the housing portion 111. The cap tabs 115A may be joined to the
cap
120 by brazing, welding or other metal joining technique, or the cap tabs 115
may
be an integral part of the cap 120. In yet another embodiment, the cap 120 is
joined
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to the housing portion 111 by welding, brazing, or other metallurgical bonding
technique, and no mechanical fastener is required.
[00351 The coupling 130 is attached to the cap body 120a. In one embodiment,
the
coupling 130 is joined to the cap body 120a by a metal joining technique, such
as,
but not limited to, brazing or welding. In another embodiment, the coupling
130 is
integral to the cap body 120a. The coupling 130 includes a recess 132 and an
opening 133 through the coupling 130 that traverses the recess 132. In this
exemplary embodiment, the coupling 130 is a standard power take-off (PTO)
coupling. In another embodiment, the opening 133 receives a pin (not shown)
for
temporarily locking a PTO in the recess 132. The power take-off coupling may
be
connected to a tractor or drive of a vehicle or power equipment In another
embodiment, the coupling 130 may be a coupling capable of releasably
connecting
to a rotational and/or vibrational mechanical power device, such as, but not
limited
to a power take-off, drill or other power rotational device.
[00361 Figs. 2A and 2B shows a another embodiment of a tree stump removal
device 200 according to the invention. As can be seen in Fig. 2, the tree
stump
removal device 200 includes a body 210 and a top portion or cap 220. The body
210 includes a housing or housing portion 211 and a cutting portion 212. The
housing portion 211 includes a first portion 211a and a second housing portion
211b. The first housing portion 211a and second housing portion 211b have a
groove 251 and tongue or projection 252, respectively, for aligning and
stabilizing
the first and second housing portions 211a, 211b during assembly. The first
and
second housing portions 211a, 211b include openings 216 for receiving
fasteners
253. In another embodiment, the openings 216 may be omitted.
[0037] When assembled as shown in Fig. 2A, the housing portion 211 has a
generally tapered tubular shape having a length L extending from a top end 213
to
a bottom end 214. The housing portion 211 has a first outside diameter OD1 at
the
top end 213 and a second outside diameter 0D2 at the bottom end 214, that are
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similar to those shown in Fig. 1. The housing portion 211 further has a first
inside
diameter ID1 at the top end and a second inside diameter ID2 at the bottom end
214 similar to those shown in Fig. 1. In this exemplary embodiment, ID1 is
greater
than ID2. The change in diameter from ID1 to ID2 is proportional to L. In one
embodiment, the ratio of decreasing diameter to length is between about
0.125:12
to about 2.0:12. In another embodiment, the ratio of decreasing diameter to
length
is between about 0.25:12 to about 1.0:12. In yet another embodiment, the ratio
of
decreasing diameter to length is between about 0.5:12 to about 0.75:12. In yet
another embodiment, the housing portion 211 may have a constant internal
diameter over L, or in other words ID1 is equal to 11)2. In yet another
embodiment,
the housing portion 211 may have a discontinuous internal diameter over L. The
housing portion 211 may be formed of a metal, metal alloy or composite, such
as,
but limited to ferrous or nonferrous metals, and composites, such as, but not
limited to a steel or aluminum alloy.
[0038] The cutting portion 212 is attached to or integral with and extends
from the
bottom end 214 of the housing portion 211. The cutting portion includes a slot
264
that receives a corresponding protrusion 265 of the main portion 211 to fasten
or
join the cutting portion 212 and body portion 211 together. In another
embodiment
and cutting portion 212 and main portion 211 may be joined by a fastener, such
as,
but not limited to a pin, bolt, or clip.
[00391 The cutting portion 212 includes a cutting portion body 212a and
cutters
218. The cutters 218 may be referred to as cutting teeth. The cutting portion
212
has a same or approximately the same second inside diameter ID2 as the bottom
end 214 of the housing portion 211. In this exemplary embodiment, the cutters
218
are formed into the cutting portion 212. The cutters 218 may be formed into
the
cutting portion 212 by cutting, grinding or other metal forming method. In
this
embodiment, the cutters 218 are directional, or in other words, pitched to cut
in a
particular rotational direction R of the tree stump removal device 200. In
another
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embodiment, the cutters 218 may be bi-directional. In another embodiment, the
cutters 218 may be hardfaced with an appropriate hardfacing material. In
another
embodiment, the cutters 218 may be inserts or bits joined to the cutting
portion 212
by a metal joining technique, such as, but not limited to, brazing or welding.
[0040] The cutters 218 include a cutting face or surface 218a. In this
exemplary
embodiment, the cutting surface 218a is the exposed surface of the cutters
218. In
another embodiment, the cutting surface 218a may be hardfaced with an
appropriate hardfacing material. In another embodiment, the cutting surface
218a
be a surface of an inserts or the like that are attached, fastened or
otherwise joined
to the cutters 218.
[0041] The cap 220 includes a cap body 220a, a coupling 230, and an insertion
portion 282. The cap 220 is capable of joining to the main portion 211. The
insertion portion 282 includes holes 283 that correspond to openings 216. The
holes 283 are threaded to receive a threaded fastener 253, such as, but not
limited
to a bolt and screw, to releasably fasten the first and second main portions
211a,
211b to the cap 220. In another embodiment, the first and second main portions
211a, 211b may be releasably attached to the cap 220 by any suitable
releasable
fastener including, but not limited to, tabs, pins, and couplings. The
insertion
portion 282 has an outside diameter OD3B. In this exemplary embodiment 0D3 is
approximately equal to the interior diameter ED1 (Fig. 1) of the assembled
main
portion 213 at the top end 213.
[0042] The coupling 230 is attached to the cap body 220a. In one embodiment,
the
coupling 230 is joined to the cap body 220a by a metal joining technique, such
as,
but not limited to, brazing or welding. In another embodiment, the coupling
230 is
integral to the cap body 220a. The coupling 230 includes a recess 232 and an
opening 233. In this exemplary embodiment, the coupling 230 is a standard
power
take-off (PTO) coupling. In another embodiment, the opening 233 receives a pin
(not shown) for temporarily locking a PTO in the recess 232. The power take-
off
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coupling may be connected to a tractor or drive of a vehicle or power
equipment.
In another embodiment, the coupling 230 may be a coupling capable of
releasably
connecting to a rotational device, such as, but not limited to a rotational
mechanical power device, such as, but not limited to a power take-off, a drill
or
other power rotational device. The coupling 230 may be joined to the cap body
220a by brazing, welding or other metal joining technique, or the coupling 230
may be an integral part of the cap 220.
[0043] Figs. 3A and 3B shows another embodiment of a tree stump removal
device 300 according to the invention. As can be seen in Figs. 3A and 3B, the
tree
stump removal device 300 includes a body portion 310 and a top portion or cap
320. The body 310 includes a housing portion 311 and a cutting portion 312.
The
housing portion 311 has a preselected length L extending from a top end 313 to
a
bottom end 314. The main portion 311 includes slots 311a that pass through to
an
interior space 391 defined by the main portion 311. In this embodiment, the
main
portion 311 includes three slots 311a. In another embodiment, the main portion
311 may include one or more slots 311a.
[0044] The housing 311 further includes tabs 315 having openings 316 for
receiving fasteners 317. In this exemplary embodiment, the housing 311 has a
constant internal diameter ID 1 over the length L of the housing portion
extending
from the top end 314 to the bottom end 314. In another embodiment, the housing
311 may have a discontinuous internal diameter ID1' over L. In yet another
embodiment, the housing 311 may have a decreasing, tapered internal diameter
from the top end 313 to the bottom end 314.
[0045] The cutting portion 312 is joined to the bottom end 214 of housing 311.
In
this exemplary embodiment, the cutting portion 312 are projections or cutters
that
have been formed from a portion of the housing 311. In one embodiment, the
cutting portion 312 may be hardfaced. In this exemplary embodiment, the
cutting
portion 312 includes three cutters (one cutter hidden in rear). In another
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embodiment, the cutting portion 312 may include one or more cutters. In
another
embodiment, the cutting portion 312 may be joined by a metal joining technique
such as, but not limited to brazing or welding. In one embodiment, the cutting
portion 312 includes a cutting portion body joined to the main body 311 to
which
teeth or cutters are joined.
[0046] The cap 320 includes a cap body 320a, a coupling 330, and a core screw
340. The cap 320 is capable of joining to the housing 311. The cap body 320a
includes slots or openings 322 for receiving tabs 315 and holes or fastener
openings 316a for receiving a fastener 317. The fastener 317 may be a bolt,
pin,
hitch pin, or other engaging device for securing the cap 320 to the body 310.
The
fastener 317 may be threaded or unthreaded. The cap body 320 includes openings
322 radially distributed at different radius from the centerline or vertical
axis Z of
the tree stump removal device 300. In such a manner, the cap 320 may be
releasably attached to a body 310 of various diameters.
[0047] The coupling 330 includes a recess 332 and an opening 333. In this
exemplary embodiment, the coupling 330 is a power take-off (PTO) coupling. In
another embodiment, the opening 333 receives a pin (not shown) for temporarily
locking a PTO in the recess 332. The power take-off coupling may be connected
to
a tractor or drive of a vehicle or power equipment. In another embodiment, the
coupling 330 may be a coupling capable of releasably connecting to a
rotational
device, such as, but not limited to a rotational mechanical power device, such
as,
but not limited to a power take-off, drill or other power rotational device.
The
coupling 330 may be joined to the cap body 320a 320 by brazing, welding or
other
metal joining technique, or the coupling 330 may be an integral part of the
cap
320.
[0048] The core screw 340 is received in the opening 332. The core screw is
releasably attached within the opening 332 by a fastener 317b received through
openings 333b and 333c. The fastener may be a bolt, pin, hitch pin, or other
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engaging device for releasably engaging the core screw 340 to the coupling
330. In
another embodiment, the core screw 340 may be omitted. In yet another
embodiment, the core screw 340 and the opening 333b may be omitted. The core
screw 340 includes a threaded portion 340a for releasably engaging a material,
such as a tree stump, in the interior of the main portion 311a. In such a
manner, the
core screw 340 may engage and extract a tree stump from the ground after the
cutting portion 312 cuts and/or severs roots extending from the tree trunk.
[0049] Fig. 4A illustrates another exemplary embodiment of a tree stump
removal
device 400. As can be seen in Fig. 4A, the tree stump removal device 400
includes
a body portion 410 and a top portion or cap 420. The body portion 410 includes
a
housing portion 411 and a cutting portion 412. The housing portion 411 has a
generally cylindrical tubular shape having a length L extending from a top end
413
to a bottom end 414. The body portion 411 has an outside diameter OD1* and an
inside diameter ID1*.
[0050] The housing portion 411 includes a first housing portion 411a and a
second
housing portion 411b. The first and second housing portions 411a, 411b are
joined
by a material joining technique, such as, but not limited to welding or
brazing. In
another embodiment, the first and second housing portions 411a, 411b may be
joined by mechanical fastening. In another embodiment, the housing portion 411
is
a single, unitary body. In yet another embodiment, the housing portion 411 is
formed to two or more body portions. The housing portion 411 further includes
openings 416 for receiving fasteners 417. In this exemplary embodiment, the
housing portion 411 includes three openings 416. In another embodiment, the
housing portion 411 may include two or more openings 416. The fasteners 417
may be, but is not limited to, a pin, bolt or screw. The housing portion 411
may be
formed of a metal, metal alloy or composite, such as, but limited to ferrous
or
nonferrous metals, and composites. For example, the housing portion 411 may be
formed of steel or aluminum alloy.
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10051] The cap 420 includes a cap body 420a and a coupling 430. The cap 420 is
capable of joining to the housing portion 411. The cap 420 has an outside
diameter
0D3*. In this exemplary embodiment 0D3* is approximately equal to or slightly
less than 1D1* so that the cap body 420a may be at least partially received in
the
housing portion 411. The cap 420 includes openings 416a that correspond to
openings 416 so as to further receive fasteners 417. In such a manner openings
416
and 416A are aligned when the cap 420 is joined to the housing portion 411. In
another embodiment, the openings 416a may be threaded. The cap 420 may further
be attached to the housing portion 411 by a metal joining technique, such as,
but
not limited to brazing or welding. In another embodiment, the openings 416 and
416a may be omitted, and the cap 420 may be joined to the housing portion 411
by
a metal joining technique, such as, but not limited to brazing or welding.
[0052] The coupling 430 is joined to the cap body 420a. In one embodiment, the
coupling 430 is joined to the cap body 420a by a metal joining technique, such
as,
but not limited to, brazing or welding. In another embodiment, the coupling
430 is
integral to the cap body 420a. The coupling 430 includes a recess 432 and an
opening 433. The opening 433 traverses through the coupling 430 and recess
432.
The opening 433 may receive to pin, bolt, or other fastener. In this exemplary
embodiment, the coupling 430 is a standard power take-off (PTO) coupling. In
an
embodiment, the recess 432 is configured to receive a standard PTO (not
shown),
and the opening 433 receives a pin, bolt or other fastener (not shown) for
temporarily coupling the PTO to the tree stump removal device 400. The power
take-off coupling may be connected to a rotational drive of a tractor,
vehicle, post
hole drill, drill or other power equipment.
[00531 Referring to Figs. 4A, 4B and 4C, the cutting portion 412 includes a
cutter
portion body 414 and cutters 418. The cutter portion body 414 includes an
insert
portion 414a. The insert portion 414a is received in and along the inside wall
411a
of housing portion 411. The cutter portion 412 is metallurgically joined to
the
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housing portion 411 by a joining technique, such as, but not limited to
brazing or
welding. In another embodiment, the cutter portion 412 is mechanically
fastened to
the housing portion by a fastener, such as, but not limited to a pin, bolt,
screw or
clip.
[0054] In this exemplary embodiment, the cutter portion 412 includes eight
cutters
418. In another embodiment, the cutter portion 412 may include one or more
cutters 418. The cutters 418 include a cutter body 418a and a cutter insert
418b.
The cutter body 418a is machined into the cutting portion 412.
[0055] The cutter insert 418b is formed of a cutter material. In one
embodiment,
the cutting insert 418b is formed of a hardened material. In one embodiment,
the
cutting insert 418b is a tungsten carbide insert. In another embodiment, the
cutting
insert 418b may be formed of a cermet, ceramic, metal, metal alloy or any
combination thereof. The cutting insert 418b includes a through hole 418c
through
which a mechanical fastener (not shown) is inserted joining the cutting insert
418b
to the cutter body 418a. The mechanical fastener may be a bolt, screw, or
other
like _device. In one embodiment, the cutting insert 418b is releasably
attached to
the cutter body 418a, so the cutting insert 418b may be replaced when worn or
broken. In another embodiment, the cutting insert 418b may be joined to the
cutter
body by a metallurgical bond, mechanical fastener, or combination thereof. In
yet
another embodiment, the cutting insert 418b is continuous part of a cutter
418, or
in other words, the cutters 418 are a single, unitary body. In yet another
embodiment, the cutter insert 418b may be omitted, ant the cutters 418 may be
hard faced with an appropriate hard facing material.
[0056] Fig. 4D illustrates another embodiment of the cutter portion 412 and
cutters
418. As can be seen in Fig. 4D, the cutter portion 412 includes a slot 412a
for
receiving cutters 418. The cutters 418 are metallurgically joined to the
cutter
portion 412 by a bonding technique, such as, but not limited to brazing or
welding.
In another embodiment, the cutter 418 is received in a housing slot 411b and
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joined to the cutting portion by a metallurgical and or mechanical joining
technique. The mechanical joining technique may use a mechanical fastener,
such
as, cut not limited to a screw, bolt or pin.
[0057] The cutters 418 include a cutter body 418a and a cutter insert 418b.
The
cutter body 418a may be formed of metal, metal alloy, ceramic, or composite.
In
one embodiment, the cutter body 418a may be formed of a hardened steel or
aluminum. In one embodiment, the cutter insert 418b is tungsten carbide
composite. In another embodiment, the cutter insert 418b may be formed of a
cermet, ceramic, composite, metal, metal alloy or any combination thereof.
[0058] In an embodiment of a method of operating the tree stump removal device
400, the tree stump removal device 400 is coupled via coupling 430 to a
mechanical rotary device (not shown), such as, but not limited to, a power
take off
of an industrial machine, such as, but not limited to, a tractor, post hole
driller,
drill, or other like device. In one embodiment, the tree stump removal device
400
is selected to have the main portion 411 having an inside diameter greater
than the
diameter of a tree stump selected for removal.
[0059] The tree stump removal device 400 is then place over the tree stump.
The
rotary mechanical device is switched on so as to rotate the tree stump removal
device 400 about the Z axis. The tree stump removal device 400 is then lowered
towards the ground. The tree stump removal device 400 is continued to be
lowered
as the cutters 418 engage the ground and/or tree roots. The tree stump removal
device 400 is lowered until the cutting portion 412 enters the ground to a
desired
depth. The desired depth is selected to sever some, most, or all of the roots
of the
stump horizontally extending therefrom. The tree stump removal device 400 is
then raised from the desired depth and the severed tree stump is removed. In
one
embodiment, the tree stump is partially retained in the main portion 411 when
the
tree stump removal device 400 is raised. In another embodiment, tree stump
removal device 400 includes a core screw 340 (Fig. 3A), and the tree stump is
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CA 02915111 2015-12-11
engaged by a core screw 340 and is partially retained in the main portion 411
when
the tree stump removal device 400 is raised. In yet another embodiment, the
tree
stump remains in the ground after the tree stump removal device 400 has been
raised, and the tree stump may be removed from the ground or left to decay in
the
ground.
[0060] Figures 5-9 depict a preferred embodiment of the tree stump removal
device of the present invention. Figure 5A depicts only the cutter portion
body 514
of the body portion of the preferred embodiment, as the cap portion and the
housing portion may assume any of the configurations depicted in the
previously
described embodiments depicted in Figures 1-4. In this embodiment, cutter
portion
body is integral with body portion 410. Cutter portion body 514 may be
attached to
housing portion 411 metallurgically, as previously described, or it may be
machined as part of the body portion, forming for example a body portion
fabricated as a single cylindrical piece. Cutter portion body 514 as shown in
Figure
5A and 5B does not include any cutter assemblies or cutter inserts. Cutter
portion
body 514 includes a plurality of notches 535 machined into its lower
circumference. The notches are formed in the circumference a distance of 1-cl
from
the bottom surface of cutter portion body. While a plurality of notches 535
may be
formed in cutter portion body 514, three notches are preferred, as shown in
Figure
5B which is view of cutter portion body 514 from the bottom looking toward the
cap. The notches may span any circumferential distance c. Also depicted in
Figure
5A is a radially oriented aperture 539. One aperture 539 is positioned above
each
of the plurality of notches 535 formed in cutter portion body 514.
[0061] Referring now to Figures 6 and 7 are cutter holder and cutter insert
555.
Figure 6A is a side view of cutter holder 545. Figure 6B depicts a front view
of the
cutter holder of Figure 6A. Cutter holder 545 includes a pair of arms 547
extending from a base 549. Cutter holder has a length of 1 as shown in Figure
6A,
while the arms extend a distance of d toward a cutter holder base 549. The
base
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CA 02915111 2015-12-11
thus has a size of 1-d which corresponds to the notch dimension 1-d depicted
in
Figure 5, so that base matches the notch, fitting into notch 535. Pair of arms
547
are separated by a distance t. Distance t corresponds to the thickness of the
cutter
portion body 514 which may vary from 100-500 mils (1/10 ¨ 1/2 inch). Base 549
of cutter holder 545 further includes a countersink 551 which receives cutter
insert
555. Countersink 551 has a radius r (and a diameter of 2r). Radius r is less
than (1-
d)/2 or 2r is less than (1-d). [(1-d) -2r] is a dimension that represents a
wall
thickness y of the countersink, that is [(1-d)-2r] = 2y. Countersink 551
further
includes countersink aperture 553 which is threaded to receive a
correspondingly
threaded fastener. The preferred thickness of cutter portion body is about
0.25
inches. While the thickness of the cutter portion body may be reduced, as the
thickness is reduced, the potential for damage to the cutter portion body due
to
deformation during tree stump removal increases. The thickness of the cutter
portion body 514 may also be increased; however increasing its thickness,
which
increases rigidity, also increases weight, encumbering handling of the tree
stump
removal device. The dimensions are set forth as variables because the
dimensions
may have any physical sizes that meet these general parameters, and the
invention
should not be restricted to specific physical dimensions.
[0062] Figure 7 provides a view of cutter insert 555. Figure 7 provides a
perspective view of cutter insert 555. It can be seen that cutter insert 555
is
frustoconical in shape in the preferred embodiment. Cutter insert is
dimensioned to
fit into countersink 551 of cutter holder 545. Cutter insert 555, being
frustoconical,
has a major radius of r+y+e where e is a dimension no greater than 160 mils
(0.160
inches) and a minor radius 576 less than r. Cutter insert 555 also includes a
cutter
aperture 563 corresponding to countersink aperture 553, allowing a threaded
fastener to be inserted through cutter aperture and threaded into countersink
aperture 553, thereby securing cutter insert 555 into countersink 551 of
cutter
holder. Since the minor radius of cutter insert 555 is less than r, the narrow
end of
cutter insert 555 fits into countersink 551 allowing cutter insert 55$ to be
secured
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within countersink 551 of cutter holder 545 by a fastener. The major radius of
cutter insert 555 extends below cutter holder 545 by the dimension e, which is
no
greater than 160 mils, preferably no greater than 150 mils, and most
preferably 50-
125 mils. This dimension e represents the cutting edge of cutter insert 555.
When
the cutting edge represented by e is greater than about 160 mils, it has been
found
that any binding that occurs during tree stump removal can result in
distortion or
bending of the body portion when a body portion and cutter portion body have
the
preferred thickness of 1/4 inch. Of course, increasing the thickness of the
body
portion when the cutting edge extends beyond 160 mils can alleviate this
problem,
providing a thicker and stiffer tool, but with increased weight and decreased
handleability. Although cutter insert 555 is described in its preferred
embodiment
as having a frustoconical shape, one skilled in the art would recognize that
cutter
insert 555 may also be fabricated in other shapes, such as but not limited to
a
cylindrical part having a plurality of radii, a first radii at one end being
smaller
than radius r and a second radius at the opposite end sized to r+y+e. Cutter
insert
555 preferably comprises a carbide tool steel although it may comprise a hard-
faced part, where the hard faced material is a wear resistant material.
10063] Figure 8 depicts cutter insert 555 assembled to cutter holder 545, and
cutter
holder assembled into a corresponding notch 535 of cutter portion body 514.
The
plurality of notches 535, which are radiused to correspond to the radius of
the
cutter portion body, slide over the cutter portion body 514 as one cutter
holder 545
is assembled into each notch of the plurality of notches 535. A second
aperture 554
extending through arms 547 of cutter holder 545 align with aperture 5339 in
cutter
portion body 514, allowing cutter assembly 575 comprising cutter insert 555
and
cutter holder 545 to be secured to cutter portion body 514. As can be seen
from
Figure 8, cutting edge e of cutter insert 555 extends below cutter portion
body 514.
Once assembled, the major diameter (twice the radius) of cutter insert edge
extends
below cutter portion body perpendicular to the direction of rotation of the
tool by a
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distance e which, as discussed may extend up to 160 mils (0.160 inches)
maximum.
[0064] This preferred design is easy to assemble and disassemble. It allows
for
ready replacement of the cutter inserts 555 as they wear, the cutter inserts
experiencing most of the wear, while the cutter holder 545 and cutter portion
body
514 experience very little wear allowing them to be used until they experience
wear, which may be indefinitely. Surprisingly, this design also allows for
easy
removal of the tree stump after it has been extracted. As the cut around the
tree
stump is made, severing side roots, debris and soil accumulates between the
stump
and the inner diameter of the tree stump removal tool, compacting as the tree
stump removal tool rotates. After all side roots have been cut, the stump and
the
compacted debris and soil are captured within the inner diameter of the tree
stump
removal tool. The stump eventually rotates with the tree stump removal tool
and
causes loosening or breaking of any tap root that may be present. The stump
(along
with the debris and compacted soil) may then be lifted out of the ground. With
this
preferred design, the tree stump and compacted soil and debris captured within
the
tree stump removal tool are readily removed by shaking the tree stump removal
tool. The soil and debris are held tightly within the inner diameter by one of
arms
547 for each cutter holder, but soil and debris are readily removed adjacent
arms
547 by shaking, ultimately resulting in release of the stump from the tree
stump
removal tool.
[0065] Referring again to Figure 6A and Figure 6B, the countersink 551 is
shown
centered into cutter holder 545. One skilled in the art will understand that
by
slightly varying the dimensions of cutter holder 545, countersink 551 can be
fabricated so that it is not centered but biased, either to the right or to
the left of the
configuration shown in Figure 6. Thus when assembled into notches 535, the
cutting edge of cutter insert may extend downward but instead of being
centered,
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CA 02915111 2015-12-11
either biased more toward the inside diameter of cutter portion body 514 or
biased
more toward the outside diameter of cutter portion body 514.
[0066] In one preferred embodiment in which three cutter inserts 555 are
assembled to three cutter holders, one cutter insert 555 is centered in a
cutter
portion body 514 configured as shown in Figure 8, one is biased more toward
the
inside diameter of cutter portion body 514 and one is biased more toward the
outside diameter of cutter portion body 514. This embodiment provides a cut
having a maximum kerf as compared to an assembly in which all cutter inserts
555
are oriented in cutter holders the same way.
[0067] The present invention has been described as a tree stump removal
device,
the tree stump removal device having preselected diameters up to 24 inches,
and
preferably from one foot (12 inches) to two feet (24 inches) in diameter.
Although
the tree stump removal device is described as limited to maximum sizes having
diameters up to 24 inches, this limitation is related to costs, as the costs
increase
with increasing tree stump removal device diameter. Also, the stresses
increase
with increasing diameter, making it more likely for the tree stump removal
device
to bend during operation should binding occur unless the thickness of the
cylindrical portion of the tool is increased as previously noted.
[0068] In many situations, a tree stump removal device is selected from among
devices having a size range of the cutting diameter varies from 1-2 feet. A
tree
stump removal device with a cutting diameter larger than the cutting diameter
of
the tree stump, preferably with a cutting diameter about 2 inches larger than
the
diameter of the tree stump. As previously discussed, the tree stump removal
device
is comprised of a tubular body having a preselected length from a first end to
a
second end, the length generally being longer as the cutting diameter
increases. A
cap including a releasable coupling is attached to the first end of the
tubular body
of the tree stump removal device. Cutters are located at the second end of the
tubular body opposite the releasable coupling.
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[0069] A power rotational device is provided for attachment to the releasable
coupling. Preferably, the power rotational device is self-propelled and
includes a
power take-off. The invention envisions a device such as a tractor, a
payloader or
other similar self-propelled device that can power rotation. The power
rotational
device is attached to the coupling either before or after the tree stump
removal
device is aligned over the tree stump. The cutters overlap at least some soil
or
debris adjacent to the tree stump and when the selected cutting diameter is
larger
than that of the tree stump, the cutter completely overlaps the tree stump and
is
aligned over the adjacent soil or debris.
[0070] Once power is applied, a circular slot is cut at least partially into
the soil
and debris surrounding the tree as the tree stump removal device is lowered.
The
tree stump removal device is lowered to a predetermined depth into the ground
up
to the preselected length of the tubular body, cutting any side roots
emanating from
the stump. As the tree stump removal device is lowered around the tree stump,
debris such as cutting chips from any side roots and soil is captured and
compacted
within the inside diameter of the tubular body. This compacted soil and debris
assists in maintaining the tree stump within the tree stump removal device as
the
device is lifted out of the ground by the power rotational device. After
lifting the
tree trunk out of the ground, it may be necessary to shake or otherwise
vibrate the
tree stump removal device to remove the stump and the compacted debris and
soil
from the inside diameter of the tubular body, as these are held in position by
friction forces. Of course, before initiating any stump removal, the cutters
should
be examined for damage and to assure that they can provide the appropriate
depth
of cut. When the cutters are removable, cutters that do not pass the
examination
should be replaced when the cutters are mechanically removable. For
metallurgically integrated cutters, the worn cutters should be cut off and new
cutting inserts should be welded on, or new hard facing should be applied to
the
cutting surface.
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CA 02915111 2015-12-11
[0071] However, a tree stump removal device within the specified range, up to
24
inches, can be used to remove stumps that are larger than the their maximum
inside
diameter. This is illustrated in Figure 9. In Figure 9, the tree trunk is
represented
by the circle 906 having the largest diameter. Also shown in Figure 9 are five
smaller circles 901-905. Each of the smaller circles represents the diameter
of a
tree stump removal device, the diameter of the tree stump removal device being
smaller than the tree diameter. In this example, the tree stump is removed in
five
cuts, the first cut being made with circle 901 and the subsequent cuts being
made
sequentially and represented by circles 902, 903 904 and 905. With each cut, a
portion of the stump is cut and a cut is made in the soil adjacent to the cut.
If there
are any side roots, they are cut by the tree stump removal device. In each
cut, soil
and debris are compacted within tree stump removal device. After each cut is
made, the cut stump and compacted debris are removed from the tree stump
removal device by shaking the tree stump removal device before the next cut is
initiated. This process is repeated until the tree stump has been removed, or
at least
has been removed to the depth of the tree stump removal device. A tree stump
removal device having a cutting depth of at least two feet in usually enough
to
remove most stumps. If the stump cannot be removed with a tree stump removal
device with this cutting depth, this cutting depth is sufficient to allow soil
to be
placed into the cut so that grass or other ground cover may be planted.
[0072] While particular embodiments of the present invention have been
illustrated
and described, it would be obvious to those skilled in the art that various
other
changes and modifications can be made. The scope of the claims should not be
limited by the preferred embodiments set forth in the examples, but should be
given the broadest interpretation consistent with the description as a whole.
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