Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 2959887 2017-03-03
DRIVE ASSEMBLY CLEARING MEMBER
Field of the Invention
The present invention relates to drive assembly clearing members for track
vehicles.
Background of the Invention
It is known in the art of landscaping and construction that tractors
comprising a track assembly
are well suited for travelling on muddy and un-level ground. Wheeled vehicles
may not have
proper traction for such conditions and tend to get stuck during operation.
Some track-type tractors utilize a drive assembly that drives the tractor's
track, wherein the track
is supported by a track frame that allows track oscillation as the track moves
along un-level
ground. Typically, under muddy conditions, the components of the track
assembly and drive
assembly of a track-type tractor may be covered with mud and debris during
operation. Damage
to the track may occur during operation as result of the design of the track
and drive assemblies
being susceptible to the buildup of mud and debris on certain components. This
damage can
shorten the life of a track assembly and drive, and ultimately has been a
source of much down
time.
For example, on the Caterpillar D6, D5, and D4 high drive tractors, the drive
assembly is built
with a larger outer flange to hold the gear carrier. As shown in Figure 2A,
the drive assembly
also has an inner sprocket that drives the series of track links which in turn
drives the track of the
tractor. There is a gap between the outer flange and the inner sprocket which
is susceptible to
the buildup of mud and debris. The outside of the track links run along the
gap between the outer
flange and the inner sprocket drive with a clearance of about 0.75 inches
between the bottom of
the link and the drive assembly.
When a buildup of mud and debris is present at the gap between the outer
flange and the inner
sprocket, the series of links may flex when running around the drive sprocket.
This may result in
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the drive sprocket skipping a link and shocking the internal drive gears
causing damage to the
drive. Furthermore, as the series of track links flex due to mud and debris
buildup at the gap,
damage to the series of track links can occur. Damage to track links
ultimately shortens the life
of the track assembly.
To reduce damage to a track assembly, after-market assemblies and track links
have been
implemented to overcome the problems described above. However, track failures
still occur as a
result of mud and debris buildup causing the track links to flex.
It is known that clearing devices could be implemented to clear debris from
components of track
vehicle such as the drive assembly. However, tractors such as the Caterpillar
D6, D5, and D4
high drive tractors only have certain locations where welding of a clearing
member could occur
without compromising the structure of the tractor and its components.
Furthermore, the track
frame of certain tractors, such as the Caterpillar D6, D5, and D4, oscillate
as the track moves
along un-level ground. This can cause a clearing device mounted on the track
frame to make
contact with the drive assembly as the track frame oscillates resulting in
damage to the clearing
device, the drive assembly or both.
What is needed, therefore, is an improved means for clearing debris from
specific areas of the
drive assembly that are susceptible to debris buildup, and avoiding
compromising the structural
integrity of the tractor and its components.
Summary of the Invention
The present invention therefore seeks to provide drive assembly clearing
members for track
vehicles.
According to a first broad aspect of the present invention, there is provided
a track vehicle
comprising:
a track, the track driven by a track link;
a track frame for supporting the track;
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a drive assembly adjacent to the track frame for driving the track link, the
drive assembly
comprising:
an outer flange and an inner sprocket with a gap between the outer flange and
the
inner sprocket,
wherein the sprocket is configured to engage with the track link;
wherein the gap is susceptible to buildup of mud and debris; and
a clearing member mounted on the track frame adjacent to the drive assembly
for
clearing at least some of the mud and debris, the clearing member extending
partially into the
gap between the outer flange and the inner sprocket.
In some exemplary embodiments of the first aspect, the track frame comprises a
pivot point
adjacent to the gap allowing for oscillation of the track frame as the track
makes contact with an
uneven ground surface; and wherein the clearing member is mounted to the track
frame at the
pivot point. Preferably, the clearing member is mounted to the track frame at
the pivot point in a
manner such that the clearing member avoids contact with the drive assemble as
the track frame
oscillates along the pivot point.
In some other exemplary embodiments of the first aspect, the clearing member
comprises a
mounting member mounted on the track frame and a clearing bar attached to the
mounting
member. The clearing bar extends partially into the gap between the outer
flange and the inner
sprocket. Preferably, the clearing bar is removably attached to the mounting
member. It is also
preferable that the clearing bar is attached to the mounting member in a
manner such that is
adjustably extends into the gap between the outer flange and the inner
sprocket.
In some other exemplary embodiments of the first aspect, it is preferable that
the clearing
member is welded to one of the non-stress points of the track frame.
According to a second broad aspect of the present invention, there is provided
a clearing member
for mounting to a track vehicle, wherein the track vehicle comprises a track,
the track driven by a
track link; a track frame for supporting the track; and a drive assembly
adjacent to the track
frame for driving the track link, the drive assembly comprising an outer
flange and an inner
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sprocket with a gap between the outer flange and the inner sprocket, wherein
the sprocket is
configured to engage with the track link; and wherein the gap is susceptible
to buildup of mud
and debris;
the clearing member is attachable to the track frame of the track vehicle and
configured
to extend partially into the gap between the outer flange and the inner
sprocket and clear at least
some of the mud and debris.
In some exemplary embodiments of the second aspect, the track frame comprises
a pivot point
adjacent to the gap allowing for oscillation of the track frame as the track
makes contact with an
uneven ground surface; and wherein the clearing member is mounted to the track
frame at the
pivot point. Preferably, the clearing member is mounted to the track, frame at
the pivot point in a
manner such that the clearing member avoids contact with the drive assembly as
the track frame
oscillates along the pivot point.
In some other exemplary embodiments of the second aspect, the clearing member
comprises a
mounting member mounted on the track frame and a clearing bar attached to the
mounting
member. The clearing bar extends partially into the gap between the outer
flange and the inner
sprocket. Preferably, the clearing bar is removably attached to the mounting
member. It is also
preferable that the clearing bar is attached to the mounting member in a
manner such that it
adjustably extends into the gap between the outer flange and the inner
sprocket.
In some other exemplary embodiments of the second aspect, it is preferable
that the clearing
member is welded to one of the non-stress points of the track frame.
Brief Description of the Drawinas
In the accompanying drawings, which illustrate exemplary embodiments of the
present
invention:
Figure 1 is a side elevation of a typical track vehicle with an oscillating
frame;
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Figure 2A is a perspective view of a drive assembly and track assembly of a
typical track
vehicle;
Figure 213 a detail view of a drive assembly and track assembly of a typical
track vehicle;
Figure 3 is a detail view of a damaged track link;
Figure 4 is a detail view of a damaged internal gear;
Figure 5 is a perspective view of a drive assembly and track assembly of a
typical track
vehicle that is not susceptible to build-up;
Figure GA is a perspective view of a first embodiment of the present invention
mounted
on a track vehicle;
Figure 613 is a side elevation view of the first embodiment of the present
invention
mounted on a track vehicle;
Figure 6C is a perspective view of the first embodiment of the present
invention mounted
on a track vehicle;
Figure 7A is a simplified side view of a second embodiment of the present
invention
mounted on a track vehicle;
Figure 711 is a simplified side view of a second embodiment of the present
invention
mounted on a track vehicle;
Figure SA is a perspective view of an aspect of an exemplary embodiment of the
present
invention;
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Figure 8b is a perspective view of an aspect of an exemplary embodiment of the
present
invention;
Figure 8C is a perspective view of an aspect of an exemplary embodiment of the
present
invention;
Figure 9 is a perspective view of an exemplary embodiment of the present
invention; and
Figure 10 is a perspective view of a drive assembly that has been cleared by
the first
embodiment of the present invention mounted on a track vehicle.
Exemplary embodiments of the present invention will now be described with
reference to the
accompanying drawings.
Detailed Description of Exemplary Embodiments
'Throughout the following description, specific details are set forth in order
to provide a more
thorough understanding to persons skilled in the art. However, well-known
elements may not
have been shown or described in detail to avoid unnecessarily obscuring the
disclosure. The
following description of examples of the technology is not intended to be
exhaustive or to limit
the invention to the precise form of any exemplary embodiment. Accordingly,
the description
and drawings are to be regarded in an illustrative, rather than a restrictive,
sense.
The present invention is directed to clearing members that clear buildup of
mud and debris from
the drive assembly of certain types of track vehicles. In particular, the
present invention is
directed to clearing members that clear buildup of mud and debris from the
drive assembly of
certain types of track vehicles that have an oscillating track frame.
A track vehicle that utilizes an oscillating track frame that allows the track
to oscillate as the
track moves along un-level ground is shown in Figure 1. Track vehicles of this
kind may have
design problems that facilitate the buildup of mud and debris in the area of
the drive that runs the
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track assembly. For example, on the Caterpillar D6, D5, and D4 high drive
tractors, the drive
assembly is built with a larger outer flange to hold the gear carrier. As
shown in Figure 2A and
Figure 2B, the drive assembly 211 also has an inner sprocket 202 that drives
the series of track
links 203 which in turn drives the track 204 of the tractor. There is a gap
205 between the outer
flange 206 and the inner sprocket 202 which is susceptible to the buildup of
mud and debris. The
outside of the track links 203 runs along the gap 205 between the outer flange
206 and the inner
sprocket drive 202. The track links typically have a clearance of about 0.75
inches between the
bottom of the link 203 and drive assembly 211 (at the gap 205).
When operating a track vehicle in conditions that entail moist soil, snow or
mud, a buildup of
material and debris may begin to form at the gap 205 between the outer flange
206 and the inner
sprocket 202. Figure 2B shows the buildup of debris at the gap. This may cause
the track links
203 to flex when running around the drive sprocket 202. As a track link 203
comes around the
sprocket 202, material that has built up at the gap 205 may begin to lift one
side of the track link
203. This can result in a side flex of the track as it rotates. As a result of
the flex, the seals that
hold lubrication for the track link 203 may be damaged allowing the
lubricating oil to sweat out
and ultimately cause damage to the track due to lack of lubrication. By having
the link assembly
flex up on one side, it runs off-centre when engaging with the sprocket 202
causing the sprocket
202 to run tight against the outside of the track assembly. This potentially
presses debris against
the inside of a track link 203 which may damage the seals of the link bushing.
Figure 3 shows
damage 301 to the track link 303 as a result of the sprocket engaging tightly
to one side of the
track assembly because of the flex in the track assembly caused by the buildup
of debris at the
gap.
A buildup of material at the gap 205 may also cause the drive sprocket 202 to
skip a link of the
track assembly, potentially damaging the internal drive gears. Figure 4 shows
damage 401 to the
internal drive gears 400 caused by the drive sprocket 202 skipping in the link
assembly.
Damage to track links ultimately shortens the life of the track assembly.
Approximately a twenty
to fifty percent reduction of life of the track assembly and other drive
components may be
attributed to the problems resulting from the buildup of debris at the gap.
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Track vehicles, such as the Caterpillar D4, D5, and D6, have the design flaw
described above as
a result of having a single reduction drive and having an outer flange that
holds the internal
carrier assembly. As shown in Figure 5, the Caterpillar D7 and D8 track
vehicles have a double
reduction carrier assembly in which case they have a different design and no
outer flange. As a
result of this, there is more clearance between the link assembly and the
drive assembly. This
allows mud and debris to be pushed off the drive assembly and thus does not
have the same
debris buildup problems as in the Caterpillar D4, D5, and D6 models.
.. The present invention involves an improved means for clearing debris from
areas of a drive
assembly that are susceptible to debris buildup, while avoiding compromising
the structural
integrity of the tractor and its components. Preferably, in embodiments
wherein a track vehicle
comprises an oscillating track frame, the present invention avoids contact
with the drive
assembly or the other components of the track vehicle as the track frame
oscillates.
As generally shown in Figures 6A to 6C, a clearing member 610 according to one
exemplary
embodiment of the present invention, mounted on a track vehicle, is for
clearing debris from
certain areas of the drive assembly that are susceptible to debris buildup.
During operation of the
track vehicle, the drive assembly 611 rotates allowing the clearing member 610
to clear at least
some of the mud and debris from areas of the drive assembly 611 that are
susceptible to debris
buildup. With the drive assembly clean 611, no flexing occurs on the track
link assembly, thus
reducing the associated problems described above. This can maximize the life
of the track
assembly, drive and other structural moving components of the drive.
According to the first exemplary embodiment of the present invention there is
provided a
clearing member 610 for mounting to a track vehicle.
The clearing member 610 of the first embodiment of the present invention may
be mounted on a
track vehicle so that it is able to clear debris from areas of the drive
assembly 611. Furthermore,
the clearing member 610 should be mounted on the track frame as mounting on
other areas of the
track vehicle may jeopardize the integrity of the vehicle's structure. On
track vehicles that
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comprise an oscillating track frame 613, the clearing member 610 should be
mounted at a
location such that the clearing member 610 avoids contact with the drive
assembly 611 or other
components of the track vehicle while the track frame 613 oscillates. During
oscillation, a track
frame 613 pivots along a pivot point 612 resulting in areas of the track frame
613 alternatingly
travelling away from and towards the drive assembly 611. Areas of the track
frame that are
closer to the pivot point 612 are less effected by oscillation and thus travel
less. Preferably, the
clearing member 610 is mounted on the track frame in a location that is
essentially at the pivot
point 612 during oscillation. By positioning the clearing member in this
manner, contact
between the clearing member and the drive assembly 611 may be avoided while
the track frame
.. oscillates.
In some preferred embodiments, the clearing member 610 is configured to be
mounted onto a
track vehicle comprising a drive assembly 611 adjacent to the track frame 613
for driving the
track links. The drive assembly 611 comprises an outer flange 603 and an inner
sprocket 602
with a gap 605 between the outer flange 603 and the inner sprocket 602. The
clearing member
610 is, preferably, mounted on the track frame adjacent to the drive assembly
611 for clearing at
least some of the mud and debris. The clearing member 610 extends partially
into the gap 605
between the outer flange 603 and the inner sprocket 602. During track vehicle
operation, the
drive assembly rotates allowing the clearing member 610 of the present
invention to clear at least
some of the mud and debris between the outer flange 603 and the drive sprocket
602.
Figures 7A and 7B illustrate a clearing member 710 according to an exemplary
embodiment of
the of the present invention mounted on the track frame in a location that is
essentially at the
pivot point 712 thus avoiding contact with drive assembly 711 during
oscillation of the track
frame.
The clearing member of is preferably made of steel. The clearing member of
some embodiments
of the present invention may be of unitary construction.
Preferably, the clearing member comprises a number of components. For example,
a clearing
member may comprise a mounting member and a clearing bar. Turning to Figures
8A to 8C,
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such mounting members of the of the present invention are illustrated. Figures
8A to 8C show
several mounting members 814a, 814b and 814c configured to be mounted onto a
track frame
under and adjacent to the drive assembly. For example, the mounting members
shown in 8A to
8C can be mounted on either the D6H, D6R and D6T Caterpillar high drive track-
type tractor
(built before 2011), the D6T Caterpillar high drive track-type tractor (built
from mid-2011 to
present) or the D6N Caterpillar high drive track-type tractor, respectively.
In the illustrated embodiments, holder blocks 815 are to be welded onto the
track frame at
locations that will not jeopardize the integrity of the track frame's
structure. A person skilled in
the art would know of locations where the welding of holder blocks 815 will
not jeopardize the
integrity of the track frame's structure. The mounting member is attached to
the holder blocks.
Preferably, the mounting member removably attaches to the holder blocks 815.
As shown in
Figures 8A to 8C, the mounting member 814 may be attached to the holder blocks
815 by using
a bolt 816 that passes through an aperture 817 in the mounting member 814 and
into a threaded
receptacle in the holder blocks 815. A person skilled in the art would know of
other ways to
mount the mounting member 814 onto the track frame suitable for application to
embodiments of
the present invention.
Figure 9 shows a mounting member 914 with a removably attached clearing bar
918. The
clearing bar 918 may removably attach to the mounting member 914 to form a
clearing member
910. This allows for replacement of the clearing bar 918 as it gets worn. The
clearing bar 918
may be attached to the mounting member 914 by using a bolt and nut, wherein
the bolt passes
through apertures 920, 921 in clearing bar 918 and the mounting member 914. A
person skilled
in the art would know of other ways to attach the clearing bar to the mounting
member suitable
for application to embodiments of the present invention.
Preferably, the clearing bar 918 is adjustably attached to the mounting member
so that it can
selectively extend out or retract in relative to the mounting member 914. This
would allow for
adjustments of the clearing member 910 so that there is a clearance between
the clearing bar 918
and drive assembly that is large enough so that contact is avoided during
oscillation or vibration
of the track frame, while not being too large such that debris can be wedged
between the clearing
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bar 918 and drive assembly 911. For example, approximately 0.25 - 0.35 inches
between the
clearing bar 918 and the drive may be a suitable clearance so that when the
clearing member 910
clears debris from the drive assembly it provides a suitable clearance between
a track link and
the drive assembly, while avoiding contact between the clearing bar 918 and
the drive. A person
skilled in the art would know of a suitable clearance between the cleaning bar
918 and the drive
assembly, and would selectively adjust the clearing member 910 accordingly.
The present invention is not limited to a track vehicle with the particular
drive assembly as
described herein. The present invention may be configured to mount onto other
track vehicles
while avoiding contact with components of the track vehicle during situations
such as track
frame oscillation.
Turning to Figure 10, the drive assembly 1011 is illustrated wherein debris
has been cleared at
the gap 1005 by a clearing member of the present invention.
The present invention further includes track vehicles provided with clearing
member / assemblies
as described herein.
A person skilled in the art would know of various assemblies suitable for
application to
embodiments of the present invention.
Unless the context clearly requires otherwise, throughout the description and
the claims:
= "comprise", "comprising", and the like are to be construed in an
inclusive sense, as opposed to
an exclusive or exhaustive sense; that is to say, in the sense of "including,
but not limited to".
.. = "connected", "coupled", or any variant thereof, means any connection or
coupling, either direct
or indirect, between two or more elements; the coupling or connection between
the elements can
be physical, logical, or a combination thereof.
= "herein", "above", "below", and words of similar import, when used to
describe this
specification shall refer to this specification as a whole and not to any
particular portions of this
specification.
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= "or", in reference to a list of two or more items, covers all of the
following interpretations of
the word: any of the items in the list, all of the items in the list, and any
combination of the items
in the list.
= the singular forms "a", "an" and "the" also include the meaning of any
appropriate plural
forms.
Vsrords that indicate directions such as "vertical", "transverse",
"horizontal", "upward",
"downward", "forward", "back wi ard", "inward", "outward", "vertical",
"transverse", "left",
"right", "front", "back", "top", "bottom", "below", "above", "under", and the
like, used in this
description and any accompanying claims (where present) depend on the specific
orientation of
the apparatus described and illustrated. The subject matter described herein
may assume various
alternative orientations. Accordingly, these directional terms are not
strictly defined and should
not be interpreted narrowly.
Where a component (e.g. a circuit, module, assembly, device, etc.) is referred
to herein, unless
otherwise indicated, reference to that component (including a reference to a
"means") should be
interpreted as including as equivalents of that component any component which
performs the
function of the described component (i.e., that is functionally equivalent),
including components
which are not structurally equivalent to the disclosed structure which
performs the function in the
.. illustrated exemplary embodiments of the invention.
Specific examples of methods and apparatus have been described herein for
purposes of
illustration. These are only examples. The technology provided herein can be
applied to
contexts other than the exemplary contexts described above. Many alterations,
modifications,
additions, omissions and permutations are possible within the practice of this
invention. This
invention includes variations on described embodiments that would be apparent
to the skilled
person, including variations obtained by: replacing features, elements and/or
acts with equivalent
features, elements and/or acts; mixing and matching of features, elements
and/or acts from
different embodiments; combining features, elements and/or acts from
embodiments as described
herein with features, elements and/or acts of other technology; and/or
omitting combining
features, elements and/or acts from described embodiments.
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The foregoing is considered as illustrative only of the principles of the
invention. The scope of
the claims should not be limited by the exemplary embodiments set forth in the
foregoing, but
should be given the broadest interpretation consistent with the specification
as a whole.
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