Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
TRACK FOR TRACTION OF A VEHICLE
FIELD
This disclosure relates generally to tracks for traction of vehicles such as
snowmobiles,
all-terrain vehicles (ATVs), and other off-road vehicles.
BACKGROUND
Certain vehicles may be equipped with tracks which enhance their traction and
floatation on soft, slippery and/or irregular grounds (e.g., snow, ice, soil,
mud, sand,
etc.) on which they operate.
For example, snowmobiles allow efficient travel on snowy and in some cases icy
grounds. A snowmobile comprises a track system which engages the ground to
provide
traction. The track system comprises a track-engaging assembly and a track
that moves
around the track-engaging assembly and engages the ground to generate
traction. The
track typically comprises an elastonneric body in which are embedded certain
reinforcements, such as transversal stiffening rods providing transversal
rigidity to the
track, longitudinal cables providing tensional strength, and/or fabric layers.
The track-
engaging assembly comprises wheels and in some cases slide rails around which
the
track is driven.
A snowmobile's track may face a number of challenges during riding. For
example,
while turning, a user may desire to shift his/her weight laterally to turn
more
aggressively, but this may cause issues as the track may be designed for
traction when
perfectly horizontal on the ground. As another example, the track may be
exposed to
different snow conditions (e.g., loose snow vs. packed snow) that can affect
its traction
and/or floatation.
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Similar considerations may arise for tracks of other types of off-road
vehicles (e.g.,
snow bikes, all-terrain vehicles (ATVs), agricultural vehicles, or other
vehicles that travel
on uneven grounds) in certain situations.
For these and other reasons, there is a need to improve tracks for traction of
vehicles.
SUMMARY
In accordance with various aspects of this disclosure, there is provided a
track for
traction of a vehicle, in which the track may have features to enhance its
traction,
floatation, and/or other aspects of its performance, including to be
lightweight, facilitate
turning, enhance acceleration, reduce noise, adapt to different ground
conditions,
and/or provide other benefits.
For example, in accordance with an aspect of this disclosure, there is
provided a track
for traction of a vehicle. The track is movable around a track-engaging
assembly
comprising a plurality of track-contacting wheels. The track comprises a
ground-
engaging outer surface for engaging the ground, an inner surface opposite to
the
ground-engaging outer surface, and a plurality of traction projections
projecting from the
ground-engaging outer surface. A central one of the tractions projections is
located
between lateral ones of the traction projections in a widthwise direction of
the track. The
central one of the tractions projections is taller than the lateral ones of
the traction
projections. A top surface of the central one of the traction projections is
substantially
flat for at least a majority of a length of the central one of the traction
projections.
In accordance with another aspect of this disclosure, there is provided a
track for
traction of a vehicle. The track is movable around a track-engaging assembly
comprising a plurality of track-contacting wheels. The track comprises a
ground-
engaging outer surface for engaging the ground, an inner surface opposite to
the
ground-engaging outer surface, and a plurality of traction projections
projecting from the
ground-engaging outer surface. A central one of the tractions projections is
located
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between lateral ones of the traction projections in a widthwise direction of
the track and
is taller than the lateral ones of the traction projections. The central one
of the traction
projections comprises a propulsive protrusion extending transversally to a
longitudinal
direction of the track and a reinforcing protrusion larger than the propulsive
protrusion of
the central one of the traction projections in the longitudinal direction of
the track.
In accordance with another aspect of this disclosure, there is provided a
track for
traction of a vehicle. The track is movable around a track-engaging assembly
comprising a plurality of track-contacting wheels. The track comprises a
ground-
engaging outer surface for engaging the ground, an inner surface opposite to
the
ground-engaging outer surface, and a plurality of traction projections
projecting from the
ground-engaging outer surface. A central one of the tractions projections is
located
between lateral ones of the traction projections in a widthwise direction of
the track. The
central one of the tractions projections is taller than the lateral ones of
the traction
projections. The central one of the traction projections occupies more than
one-third of a
width of the track.
In accordance with another aspect of this disclosure, there is provided a
track for
traction of a vehicle. The track is movable around a track-engaging assembly
comprising a plurality of track-contacting wheels. The track comprises a
ground-
engaging outer surface for engaging the ground, an inner surface opposite to
the
ground-engaging outer surface, a plurality of traction projections projecting
from the
ground-engaging outer surface, and a plurality of windows extending from the
ground-
engaging outer surface to the inner surface. A central one of the tractions
projections is
located between lateral ones of the traction projections in a widthwise
direction of the
track. The central one of the tractions projections is taller than the lateral
ones of the
traction projections. The central one of the traction projections occupies at
least 80% of
a distance between a first one of the windows and a second one of the windows
in the
widthwise direction of the track
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In accordance with another aspect of this disclosure, there is provided a
track for
traction of a vehicle. The track is movable around a track-engaging assembly
comprising a plurality of track-contacting wheels. The track comprises a
ground-
engaging outer surface for engaging the ground, an inner surface opposite to
the
ground-engaging outer surface, and a plurality of traction projections
projecting from the
ground-engaging outer surface. Each of the traction projections comprises a
propulsive
protrusion extending transversally to a longitudinal direction of the track
and a
reinforcing protrusion larger than the propulsive protrusion in the
longitudinal direction of
the track. The traction projections are disposed in a plurality of traction
rows that include
respective ones of the traction projections and that are spaced from one
another in the
longitudinal direction of the track. The traction projections are arranged in
a pattern that
spans at least three of the traction rows and repeats along the track. The
pattern of the
traction projections is configured such that the reinforcing protrusions of
respective ones
of the traction projections converge towards a centerline of the track that
bisects the
track in the widthwise direction of the track
These and other aspects of this disclosure will now become apparent to those
of
ordinary skill in the art upon review of the following description of
embodiments in
conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
A detailed description of embodiments is provided below, by way of example
only, with
reference to the accompanying drawings, in which:
A detailed description of embodiments of the invention is provided below, by
way of
example only, with reference to the accompanying drawings, in which:
Figure 1 shows an example of a snowmobile comprising a track system in
accordance
with an embodiment of the invention;
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Figure 2 shows a side view of the track system;
Figure 3 shows a perspective view of a track-engaging assembly of the track
system;
Figures 4 to 7 respectively show a perspective view, a plan view, an elevation
view, and
a longitudinal cross-sectional view of part of a track of the track system;
Figure 8 shows a widthwise cross-sectional view of part of the track;
Figures 9 shows a power consumption of the track and a power consumption of
another
track comprising lateral traction projections as high as central traction
projections,
relative to a speed of the snowmobile.
Figure 10 shows a sound emission of the track and a sound emission the other
track,
relative to the speed of the snowmobile.
Figures 11 to 14 show an example of an all-terrain vehicle (ATV) comprising
track
systems in accordance with another embodiment of the invention, instead of
being
equipped with ground-engaging wheels;
Figures 15 and 16 show an example of a snow bike comprising a track system in
accordance with another embodiment of the invention, instead of being equipped
with a
rear wheel;
It is to be expressly understood that the description and drawings are only
for the
purpose of illustrating certain embodiments and are an aid for understanding.
They are
not intended to be limiting.
DETAILED DESCRIPTION OF EMBODIMENTS
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Figure 1 shows an example of an embodiment of a vehicle 10 comprising a track
system 14. In this embodiment, the vehicle 10 is a snowmobile. The snowmobile
10 is
designed for travelling on snow and in some cases ice.
The snowmobile 10 comprises a frame 11, a powertrain 12, the track system 14,
a ski
system 17, a seat 18, and a user interface 20, which enables a user to ride,
steer and
otherwise control the snowmobile 10. The track system 14 comprises a track 21
to
engage the ground for traction of the snowmobile 10.
In this embodiment, as further discussed below, the track 21 may have features
to
enhance its traction, floatation, and/or other aspects of its performance,
including to be
lightweight, facilitate turning (e.g., by reducing friction in certain areas
of the track 21
while maintaining penetration and/or other tractive effects in others areas of
the track 21
on snow or other ground matter during cornering or otherwise turning), enhance
acceleration, reduce noise, adapt to different ground conditions (e.g.,
different types of
snow, soil, etc.), and/or provide other benefits.
The powertrain 12 is configured for generating motive power and transmitting
motive
power to the track system 14 to propel the snowmobile 10 on the ground. To
that end,
the powertrain 12 comprises a prime mover 15, which is a source of motive
power that
comprises one or more motors (e.g., an internal combustion engine, an electric
motor,
etc.). For example, in this embodiment, the prime mover 15 comprises an
internal
combustion engine. In other embodiments, the prime mover 15 may comprise
another
type of motor (e.g., an electric motor) or a combination of different types of
motor (e.g.,
an internal combustion engine and an electric motor). The prime mover 15 is in
a driving
relationship with the track system 14. That is, the powertrain 12 transmits
motive power
from the prime mover 15 to the track system 14 in order to drive (i.e., impart
motion to)
the track system 14. In some embodiments, at least part (e.g., a motor and/or
a
transmission) of the prime mover 15 may be included in the track system 14
(e.g., may
be disposed within an envelope of the track 21).
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The ski system 17 is turnable to allow steering of the snowmobile 10. In this
embodiment, the ski system 17 comprises a pair of skis 191, 192 connected to
the frame
11 via a ski-supporting assembly 13.
The seat 18 accommodates the user of the snowmobile 10. In this case, the seat
18 is a
straddle seat and the snowmobile 10 is usable by a single person such that the
seat 18
accommodates only that person driving the snowmobile 10. In other cases, the
seat 18
may be another type of seat, and/or the snowmobile 10 may be usable by two
individuals, namely one person driving the snowmobile 10 and a passenger, such
that
the seat 18 may accommodate both of these individuals (e.g., behind one
another) or
the snowmobile 10 may comprise an additional seat for the passenger.
The user interface 20 allows the user to interact with the snowmobile 10 to
control the
snowmobile 10. More particularly, the user interface 20 comprises an
accelerator, a
brake control, and a steering device that are operated by the user to control
motion of
the snowmobile 10 on the ground. In this case, the steering device comprises
handlebars, although it may comprise a steering wheel or other type of
steering element
in other cases. The user interface 20 also comprises an instrument panel
(e.g., a
dashboard) which provides indicators (e.g., a speedometer indicator, a
tachometer
indicator, etc.) to convey information to the user.
The track system 14 is configured to engage the ground to generate traction
for the
snowmobile 10. With additional reference to Figures 2 and 3, the track system
14
comprises the track 21 and a track-engaging assembly 24 for driving and
guiding the
track 21 around the track-engaging assembly 24. More particularly, in this
embodiment,
the track-engaging assembly 24 comprises a frame 23 and a plurality of track-
contacting wheels which includes a plurality of drive wheels 221, 222 and a
plurality of
idler wheels that includes rear idler wheels 261, 262, lower roller wheels 281-
286, and
upper roller wheels 301, 302. In this example, the frame 23 comprises an
elongate
support 62 including sliding surfaces 771, 772 for sliding on the track 21. As
it is
disposed between the track 21 and the frame 11 of the snowmobile 10, the track-
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engaging assembly 24 can be viewed as implementing a suspension for the
snowmobile 10. The track system 14 has a longitudinal direction and a first
longitudinal
end and a second longitudinal end that define a length of the track system 14,
a
widthwise direction and a width that is defined by a width W of the track 21,
and a
heightwise direction that is normal to its longitudinal direction and its
widthwise
direction.
The track 21 is configured to engage the ground to provide traction to the
snowmobile
10. A length of the track 21 allows the track 21 to be mounted around the
track-
engaging assembly 24. In view of its closed configuration without ends that
allows it to
be disposed and moved around the track-engaging assembly 24, the track 21 can
be
referred to as an "endless" track. With additional reference to Figures 4 to
7, the track
21 comprises an inner side 25 for facing the track-engaging assembly 24, a
ground-
engaging outer side 27 for engaging the ground, and lateral edges 881, 882. A
top run
65 of the track 21 extends between the longitudinal ends of the track system
14 and
over the track-engaging assembly 24 (including over the wheels 221, 222, 261,
262, 281-
286, 301, 302), and a bottom run 66 of the track 21 extends between the
longitudinal
ends of the track system 14 and under the track-engaging assembly 24
(including under
the wheels 221, 222, 261, 262, 281-286, 301, 302). The bottom run 66 of the
track 21
defines an area of contact 60 of the track 21 with the ground which generates
traction
and bears a majority of a load on the track system 14, and which will be
referred to as a
"contact patch" of the track 21 with the ground. The track 21 has a
longitudinal axis 85
which defines a longitudinal direction of the track 21 (i.e., a direction
generally parallel to
its longitudinal axis) and transversal directions of the track (i.e.,
directions transverse to
its longitudinal axis), including a widthwise direction of the track (i.e., a
lateral direction
generally perpendicular to its longitudinal axis). The track 21 has a
thickness direction
normal to its longitudinal and widthwise directions.
The track 21 is elastomeric, i.e., comprises elastomeric material 53, to be
flexible
around the track-engaging assembly 24. The elastomeric material 53 of the
track 21 can
include any polymeric material with suitable elasticity. In this embodiment,
the
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elastomeric material of the track 21 includes rubber. Various rubber compounds
may be
used and, in some cases, different rubber compounds may be present in
different areas
of the track 21. In other embodiments, the elastomeric material 53 of the
track 21 may
include another elastomer in addition to or instead of rubber (e.g.,
polyurethane
elastomer).
More particularly, the track 21 comprises an endless body 35 underlying its
inner side
25 and ground-engaging outer side 27. In view of its underlying nature, the
body 35 will
be referred to as a "carcass". The carcass 35 is elastomeric in that it
comprises
elastomeric material 38 which allows the carcass 35 to elastically change in
shape and
thus the track 21 to flex as it is in motion around the track-engaging
assembly 24. The
elastomeric material 38, which is part of the elastomeric material 53 of the
track 21, can
be any polymeric material with suitable elasticity. In this embodiment, the
elastomeric
material 38 includes rubber. Various rubber compounds may be used and, in some
cases, different rubber compounds may be present in different areas of the
carcass 35.
In other embodiments, the elastomeric material 38 may include another
elastomer in
addition to or instead of rubber (e.g., polyurethane elastomer).
In this embodiment, as shown in Figure 8, the carcass 35 comprises a plurality
of
reinforcements 451-45p embedded in its rubber 38. These reinforcements 451-45p
can
take on various forms.
For example, in this embodiment, a subset of the reinforcements 451-45p is a
plurality of
transversal stiffening rods 361-36N that extend transversally to the
longitudinal direction
of the track 21 to provide transversal rigidity to the track 21. More
particularly, in this
embodiment, the transversal stiffening rods 361-36N extend in the widthwise
direction of
the track 21. Each of the transversal stiffening rods 361-36N may have various
shapes
and be made of any suitably rigid material (e.g., metal, polymer or composite
material).
As another example, in this embodiment, the reinforcements 45õ 45j are
reinforcing
layers that are flexible in the longitudinal direction of the track 21.
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For instance, in this embodiment, the reinforcement 45, is a layer of
reinforcing cables
371-37m that are adjacent to one another and extend generally in the
longitudinal
direction of the track 21 to enhance strength in tension of the track 21 along
its
longitudinal direction. In this case, each of the reinforcing cables 371-37m
is a cord
including a plurality of strands (e.g., textile fibers or metallic wires). In
other cases, each
of the reinforcing cables 371-37m may be another type of cable and may be made
of any
material suitably flexible longitudinally (e.g., fibers or wires of metal,
plastic or composite
material). In some examples of implementation, respective ones of the
reinforcing
cables 371-37m may be constituted by a single continuous cable length wound
helically
around the track 21. In other examples of implementation, respective ones of
the
transversal cables 371-37m may be separate and independent from one another
(i.e.,
unconnected other than by rubber of the track 21).
Also, in this embodiment, the reinforcement 45j is a layer of reinforcing
fabric 43. The
reinforcing fabric 43 comprises thin pliable material made usually by weaving,
felting,
knitting, interlacing, or otherwise crossing natural or synthetic elongated
fabric
elements, such as fibers, filaments, strands and/or others, such that some
elongated
fabric elements extend transversally to the longitudinal direction of the
track 21 to have
a reinforcing effect in a transversal direction of the track 21. For instance,
the reinforcing
fabric 43 may comprise a ply of reinforcing woven fibers (e.g., nylon fibers
or other
synthetic fibers). For example, the reinforcing fabric 43 may protect the
transversal
stiffening rods 361-36N, improve cohesion of the track 21, and counter its
elongation.
The carcass 35 may be molded into shape in a molding process during which the
rubber 38 is cured. For example, in this embodiment, a mold may be used to
consolidate layers of rubber providing the rubber 38 of the carcass 35, the
reinforcing
cables 371-37m and the layer of reinforcing fabric 43.
The inner side 25 of the track 21 comprises an inner surface 32 of the carcass
35 and a
plurality of inner projections 341-34o that project from the inner surface 32
and are
CA 2980208 2017-09-22
positioned to contact the track-engaging assembly 24 (e.g., at least some of
the wheels
221, 222, 261, 262, 281-286, 301, 302) to do at least one of driving (i.e.,
imparting motion
to) the track 21 and guiding the track 21. Since each of them is used to do at
least one
of driving the track 21 and guiding the track 21, the inner projections 341-
34D can be
referred to as "drive/guide projections" or "drive/guide lugs". In some cases,
a
drive/guide lug 34, may interact with a given one of the drive wheels 221, 222
to drive the
track 21, in which case the drive/guide lug 34, is a drive lug. In other
cases, a
drive/guide lug 34, may interact with a given one of the idler wheels 261,
262, 281-282,
301, 302 and/or another part of the track-engaging assembly 24 to guide the
track 21 to
maintain proper track alignment and prevent de-tracking without being used to
drive the
track 21, in which case the drive/guide lug 34, is a guide lug. In yet other
cases, a
drive/guide lug 34, may both (i) interact with a given one of the drive wheels
221, 223 to
drive the track 21 and (ii) interact with a given one of the idler wheels 261,
262, 281-286,
301, 302 and/or another part of the track-engaging assembly 24 to guide the
track 21, in
which case the drive/guide lug 34, is both a drive lug and a guide lug. A
height H, of a
drive/guide lug 34), may have any suitable value.
In this embodiment, each of the drive/guide lugs 341-34D is an elastomeric
drive/guide
lug in that it comprises elastomeric material 42. The elastomeric material 42,
which is
part of the elastomeric material 53 of the track 21, can be any polymeric
material with
suitable elasticity. More particularly, in this embodiment, the elastomeric
material 42
includes rubber. Various rubber compounds may be used and, in some cases,
different
rubber compounds may be present in different areas of each of the drive/guide
lugs 341-
34D. In other embodiments, the elastomeric material 42 may include another
elastomer
in addition to or instead of rubber (e.g., polyurethane elastomer).
The drive/guide lugs 341-34D may be provided on the inner side 25 in various
ways. For
example, in this embodiment, the drive/guide lugs 341-34D are provided on the
inner
side 25 by being molded with the carcass 35.
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In this embodiment, the carcass 35 has a thickness Te which is relatively
small. The
thickness Tc of the carcass 35 is measured from the inner surface 32 to the
ground-
engaging outer surface 31 of the carcass 35 between longitudinally-adjacent
ones of the
traction projections 581-58T. For example, in some embodiments, the thickness
T, of the
carcass 35 may be no more than 0.25 inches, in some cases no more than 0.22
inches,
in some cases no more than 0.20 inches, and in some cases even less (e.g., no
more
than 0.18 or 0.16 inches). The thickness Tc of the carcass 35 may have any
other
suitable value in other embodiments.
The ground-engaging outer side 27 of the track 21 comprises a ground-engaging
outer
surface 31 of the carcass 35 and a plurality of traction projections 581-58T
that project
from the ground-engaging outer surface 31 to enhance traction on the ground.
The
traction projections 581-581-, which may be referred to as "traction lugs" or
"traction
profiles", may have any suitable shape (e.g., straight shapes, curved shapes,
shapes
with straight parts and curved parts, etc.).
Each of the traction projections 581-58T includes a base 78 at which it
projects from the
ground-engaging outer surface 31 and a top surface 80 that is farthest from
the ground-
engaging outer surface 31. Each of the traction projections 581-58T has a
height Hp in
the heightwise direction of the track 21, a dimension Lp in the widthwise
direction of the
track 21, and a dimension Wp in the longitudinal direction of the track 21. In
this
embodiment, each of the traction projections 581-58T has a longitudinal axis
75 such
that it is elongated and its dimension Lp in the widthwise direction of the
track 21 is a
length of that traction projection and its dimension Wp in the longitudinal
direction of the
track 21 is a width of that traction projection. In this example, the
longitudinal axis 75 of
each of the traction projections 581-58T extends transversally to the
longitudinal
direction of the track 21. More particularly, in this case, the longitudinal
axis 75 of each
of the traction projections 581-58T extends in the widthwise direction of the
track 21.
In this embodiment, the ground-engaging outer side 27 of the track 21
comprises a
plurality of traction rows 831-83N that include respective ones of the
traction projections
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581-58T and that are spaced from one another in the longitudinal direction of
the track
21. Each of the traction rows 831-83N includes one or more of the traction
projections
581-58T and extends transversally to the longitudinal direction of the track
21. In this
example, each of the traction rows 831-83N is oriented to the widthwise
direction of the
track 21. Also, in this example, adjacent ones of the traction rows 831-83N
are spaced
from one another at a spacing (i.e., pitch) in the longitudinal direction of
the track 21 and
by traction-projection-free areas 891-89F (i.e., areas free of traction
projections) of the
ground-engaging outer side 27 of the track 21. Furthermore, in this example, a
given
one of the traction rows 831-83N may comprise plural ones of the traction
projections
581-58T and one or more voids 931-93p between adjacent ones of its traction
projections.
Each of the traction projections 581-58T is an elastomeric traction projection
in that it
comprises elastomeric material 41. The elastomeric material 41, which is part
of the
elastomeric material 53 of the track 21, can be any polymeric material with
suitable
elasticity. More particularly, in this embodiment, the elastomeric material 41
includes
rubber. Various rubber compounds may be used and, in some cases, different
rubber
compounds may be present in different areas of each of the traction
projections 581-58T.
In other embodiments, the elastomeric material 41 may include another
elastomer in
addition to or instead of rubber (e.g., polyurethane elastomer).
The traction projections 581-58T may be provided on the ground-engaging outer
side 27
in various ways. For example, in this embodiment, the traction projections 581-
581- are
provided on the ground-engaging outer side 27 by being molded with the carcass
35.
In this example, the track 21 comprises windows (i.e., openings) 401-40H
extending
therethrough. The track 21 may comprise slide members 391-39s, which can
sometimes
be referred to as "clips", to slide against the sliding surfaces 771, 772 of
the track-
engaging assembly 24 to reduce friction and may be mounted via the windows 401-
40H.
In this case, the track 21 comprises window rows 411, 412 that include
respective ones
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of the windows 401-40H and are spaced apart from one another in the widthwise
direction of the track 21.
In this embodiment, the track 21, including its traction projections 581-58T,
may be
configured to enhance its traction, floatation, and/or other aspects of its
performance,
including, for example, to be lightweight, facilitate turning (e.g., by
reducing friction in
certain areas of the track 21 while maintaining penetration and/or other
tractive effects
in other areas of the track 21 on snow or other ground matter during cornering
or
otherwise turning), enhance acceleration, reduce noise, adapt to different
ground
conditions (e.g., different types of snow, soil, etc.), and/or provide other
benefits. For
instance, this may be useful when the user transfers his/her weight to perform
aggressive turns, when travelling on a trail that can have loose snow or other
ground
matter and/or packed snow or other ground, and/or in other situations.
For example, in this embodiment, higher central ones of the tractions
projections 581-
58T located in a central portion 70 of the track 21, such as the traction
projections 581,
582, are taller than lower lateral ones of the traction projections 581-581-
located in lateral
portions 711, 712 of the track 21, such as the traction projections 583-586,
between
which the central portion 70 of the track 21 is located. This may facilitate
turning of the
snowmobile 10. For example, with additional reference to Figure 6, the lower
lateral
ones of the traction projections 581-58-r of a given one of the lateral
portions 711, 712 of
the track 21 may provide traction while reducing penetration and friction at
the given
one of the lateral portions 711, 712 of the track 21 when the user transfer
his/her weight
towards the given one of the lateral portions 711, 712 of the track 21 for an
aggressive
turn (e.g., making it easier to tilt and allowing a rear or "tail" of the
track 21 to slide more
easily laterally), whereas the higher central ones of the tractions
projections 581-58T of
the central portion 70 of the track 21 maintain penetration and/or other
tractive effects in
the central portion 70 of the track 21 on snow or other ground matter during
turning.
The height Hp of a lower lateral one of the traction projections 581-58T,
denoted Hp1, is
thus lower than the height Hp of a higher central one of the traction
projections 581-58-r,
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denoted Hph. For example, in some embodiments, a ratio of the height Hp, of
the lower
lateral one of the traction projections 581-58T over the height Hph of the
higher central
one of the traction projections 581-581- may be no more than 95%, in some
cases no
more than 90%, in some cases no more than 85%, in some cases no more than 80%,
and in some cases even less. For instance, in this embodiment, the height Hp,
of the
lower lateral one of the traction projections 581-58T is 1.25 inches while the
height Hph of
the higher central one of the traction projections 581-581- is 1.5 inches.
In this embodiment, the central portion 70 of the track 21 that includes the
higher central
ones of the tractions projections 581-581- is disposed between the window rows
411, 412,
and thus the slide members 391-39s if applicable, while each of the lateral
portions 711,
712 of the track 21 that includes one or more of the lower central ones of the
tractions
projections 581-58T is disposed between a respective one of the window rows
411, 412
and a respective one of the lateral edges 881, 882 of the track 21 that is
closest to that
window row. This may help traction when turning as the the lower central ones
of the
tractions projections 581-581- are contained between a respective one of the
lateral
edges 881, 882 of the track 21 and a respective one of the sliding surfaces
771, 772 of
the track-engaging assembly 24. In this example, the higher central ones of
the
tractions projections 581-581- are spaced apart from the lower central ones of
the
tractions projections 581-581- in the widthwise direction of the track 21 by
one or more of
the voids 931-93p free of traction projections.
Also, in this embodiment, each of the higher central ones of the traction
projections 581-
58T occupies a significant part of the width of the track 21. For example, in
some
embodiments, each of the higher central ones of the traction projections 581-
58-1-
occupies more than one-third, in some cases at least 40%, in some cases at
least 45%,
and in some cases even more of the width of the track 21. For instance, each
of the
higher central ones of the traction projections 581-58T may occupy at least
80%, in
some cases at least 90%, and in some cases substantially an entirety of a
distance
between the window rows 411, 412 in the widthwise direction of the track 21.
CA 2980208 2017-09-22
Furthermore, in this embodiment, the top surface 80 of each of the higher
central ones
of the traction projections 581-58T is substantially flat (i.e., level) for at
least a majority
(i.e., a majority or an entirety) of the length Lp of that traction
projection. This may help
to maximize traction when the snowmobile 10 is travelling straight, while
providing
suitable penetration in snow or other ground matter when cornering. Also, in
this
embodiment, the top surface 80 of each of the lower lateral ones of the
traction
projections 581-58T is substantially flat for at least a majority of the
length Lp of that
traction projection. In this example, the top surface 80 of each of the higher
central ones
of the traction projections 581-58T is substantially flat for the entirety of
the length Lp of
that higher central traction projection, and the top surface 80 of each of the
lower lateral
ones of the traction projections 581-581- is substantially flat for the
entirety of the length
Lp of that lower lateral traction projection.
In this example of implementation, each of the traction projections 581-581-
comprises
one or more propulsive protrusions 981-98p extending transversally to the
longitudinal
direction of the track 21 and occupying most of the length Lp of that traction
projection
and one or more reinforcing protrusions 961-96s larger than the propulsive
protrusions
981-98p in the longitudinal direction of the track 21 to reinforce that
traction projection for
promoting traction and penetration on snow or other ground matter.
For instance, in this embodiment, each of the higher central ones of the
traction
projections 581-581- comprises its propulsive protrusions 981, 982 that are
respectively
disposed between its reinforcing protrusions 961-963; each of the lower
lateral ones of
the traction projections 581-58T comprises its propulsive protrusion 981 that
is disposed
between its reinforcing protrusions 961, 962, etc.
More particularly, in this example of implementation, the propulsive
protrusions 981-98p
of the traction projections 581-58T may be viewed as paddles and the
reinforcing
protrusions 961-96s of the traction projections 581-581- may be viewed as
columns that
are larger than these paddles in the longitudinal direction of the track 21 to
strengthen
the traction projections 581-58T.
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CA 2980208 2017-09-22
In this embodiment, the higher central ones of the traction projections 581-
581- are
configured to contain snow or other ground matter from the ground to enhance
traction.
Thus, a higher central traction projection 58, comprises a containment space
304 to
contain an amount of snow or other ground matter when the traction projection
58,
engages the ground. For instance, the containment space 304 of the higher
central
traction projection 58, may create a "scooping" or "cupping" action to scoop
or cup the
snow or other ground matter. The scooping or cupping action may further be
amplified
when the higher central traction projection 58, deforms as it engages the snow
or other
ground matter and causes the containment space 304 to expand.
In this embodiment, the containment space 304 of the higher central traction
projection
58, comprises a plurality of containment voids 3061, 3062 to contain
respective portions
of the amount of snow or other ground matter contained by the traction
projection 58,.
More particularly, in this embodiment, each of the containment voids 3061,
3062 is
implemented by a respective one of a plurality of recesses 3001, 3002 defined
by the
propulsive protrusions 981, 982 of the higher central traction projection 58,.
In this example, the recesses 3001-300p implementing the containment voids
3061-3064
are distributed in a longitudinal direction of the traction projection 58õ
which in this case
corresponds to the widthwise direction of the track 21. This allows the
traction projection
58, to contain the snow or other ground matter over a significant part of the
length Lp of
the traction projection 58,.
For instance, in some embodiments, the containment space 304 of the traction
projection 58, may occupy at least a majority (e.g., a majority or an
entirety) of the
length Lp of the traction projection 58,. For example, in some embodiments,
the
containment space 304 of the traction projection 58, may occupy at least 60%,
in some
cases at least 70%, in some cases at least 80%, in some cases at least 90%,
and in
some cases an entirety of the length Lp of the traction projection 58,.
17
CA 2980208 2017-09-22
In this regard, in this embodiment, each of the recesses 3001-300p of the
containment
space 304 of the traction projection 58; may occupy a significant part of the
length Lp of
the traction projection 58,. For example, in some embodiments, a recess 300,
of the
containment space 304 of the traction projection 58, may occupy at least 10%,
in some
cases at least 15%, in some cases at least 20%, in some cases at least 25%,
and in
some cases an even larger part of the length Lp of the traction projection
58,.
The containment space 304 of the traction projection 58, may therefore be
viewed as
imparting an "effective" length Leff of the traction projection 58, that
exceeds the (actual)
length Lp of the traction projection 58,. Basically, the traction projection
58, may be
viewed as generating more traction as if it was effectively longer. The
effective length
Leff of the traction projection 58, can be measured by measuring a line that
follows a
shape of the traction projection 58, from the first longitudinal end 3081 of
the traction
projection 58, to the second longitudinal end 3082 of the traction projection
58,.
Conceptually, this can be viewed as that length the traction projection 58,
would have if
it was straightened by straightening segments that are non-straight in the
longitudinal
direction of the traction projection 58, (which in this case corresponds to
the widthwise
direction of the track 21), i.e., the propulsive protrusions 2981-298p
defining the
recesses 3001-300p in this example, such that they are straight in the
longitudinal
direction of the traction projection 58,.
For instance, in some embodiments, a ratio Leff/Lp of the effective length
Leff of the
traction projection 58, over the length Lp of the traction projection 58, may
be at least
1.1, in some cases at least 1.2, in some cases at least 1.3, in some cases at
least 1.4,
and in some cases even more.
Also, in this embodiment, the containment space 304 of the traction projection
58, may
occupy at least a majority (e.g., a majority or an entirety) of the height H
of the traction
projection 58,. For example, in some embodiments, the containment space 304 of
the
traction projection 58; may occupy at least 60%, in some cases at least 70%,
in some
18
CA 2980208 2017-09-22
cases at least 80%, in some cases at least 90%, and in some cases an entirety
of the
height H of the traction projection 58.
In this regard, in this embodiment, each of the recesses 3001-300p of the
containment
space 304 of the traction projection 58; may occupy at least a majority of the
height H of
the traction projection 58. For example, in some embodiments, a recess 300; of
the
containment space 304 of the traction projection 58; may occupy at least 60%,
in some
cases at least 70%, in some cases at least 80%, in some cases at least 90%,
and in
some cases an entirety of the height H of the traction projection 58,.
The amount of snow or other ground matter that can be contained in the
containment
space 304 of the traction projection 58, may thus be significant. This can be
measured
as a volume V of the containment space 304 of the traction projection 58, in
which the
amount of snow or other ground matter can be contained. For instance, in some
embodiments, the volume V of the containment space 304 of the traction
projection 58;
may be at least 0.8 in3, in some cases at least 1 in3, in some cases at least
1.2 in3, in
some cases at least 1.4 in3 and in some cases even more. For instance, in some
cases,
a ratio V/Lp of the volume V of the containment space 304 over the length Lp
of the
traction projection 58, may be at least 0.3 in3/in, in some cases at least 0.5
in3/in, in
some cases at least 0.8 in3/in, and in some cases even more.
In this embodiment, the volume V of the containment space 304 of the traction
projection 58; corresponds to a sum of volumes v1-v4 of the recesses 3001-300p
that can
contain the snow or other ground matter. In this example, a volume v, of a
recess 300;
may be relatively significant. For instance, in some embodiments, the volume
vi of the
recess 300; may be at least at least 10%, in some cases at least 15%, in some
cases at
least 20%, in some cases at least 25%, and in some cases an even larger part
of the
volume V of the containment space 304 of the traction projection 58,.
The propulsive protrusions 2981-298p defining the recesses 3001-300p of the
containment space 304 of the traction projection 58, may be shaped in any
suitable way.
19
CA 2980208 2017-09-22
In this embodiment, each propulsive protrusion 298; is curved to define its
recess 300,.
More particularly, in this embodiment, the propulsive protrusion 298, is
generally U-
shaped such that its recess 300, is also U-shaped. The recess 300, is open
facing the
ground as the traction projection 58, approaches the ground while the track 21
moves
around the track-engaging assembly 24 when the snowmobile 10 travels forward.
In this embodiment, the traction projections 581-58T are arranged in a pattern
63 that
spans at least three of the traction rows 831-83N and repeats along the track
21. Also, in
this embodiment, the pattern 63 of the traction projections 581-58T is
symmetrical
relative to a centerline 87 of the track 21 that is parallel to the
longitudinal axis 85 of the
track 21 and bisects the track 21 in its widthwise direction. The pattern 63
of the traction
projections 581-58T may help to reduce noise generated by the track 21 in use.
More particularly, in this embodiment, the pattern 63 of the traction
projections 581-58T
is repeated at every sequence of three of the traction rows 831-83N along the
track 21.
Also, respective ones of the traction projections 581-58T of each traction row
in the
sequence of three of the traction rows 831-83N are configured differently
(e.g., shaped
differently and/or positioned differently in that traction row) than
respective ones of the
traction projections 581-58T of another traction row in the sequence of three
of the
traction rows 831-83N.
In this example of implementation, the pattern 63 of the traction projections
581-581- is
configured such that respective ones of the reinforcing protrusions 961-96s of
the
traction projections 581-58T converge towards the centerline 87 of the track
21. This
may help for penetration on the ground. For instance, this may help to create
a
"planting" effect of the track 21 on the ground that may enhance handling of
the
snowmobile 10 at higher speeds.
More specifically, in this example of implementation, the pattern 63 of the
traction
projections 581-58T is configured such that it includes lines of reinforcement
951-954 that
respectively pass through closest ones of the reinforcing protrusions 961-96s
of the
CA 2980208 2017-09-22
traction projections 581-58T of adjacent ones of the traction rows 831-83N and
converge
towards the centerline 87 of the track 21. For instance, in this embodiment,
the line of
reinforcement 952 passes through the reinforcing protrusion 961 of the
traction
projection 582 of the traction row 83,1, the reinforcing protrusion 962 of the
traction
projection 581 of the traction row 833, and the reinforcing protrusion 962 of
the traction
projection 581 of the traction row 832 and converges towards the centerline 87
of the
track 21 through the reinforcing protrusion 962 of the traction projection 582
of the next
traction row 83,1; the line of reinforcement 953 passes through the
reinforcing protrusion
963 of the traction projection 582 of the traction row 83,1, the reinforcing
protrusion 961 of
the traction projection 582 of the traction row 833, and the reinforcing
protrusion 961 of
the traction projection 582 of the traction row 832 and converges towards the
centerline
87 of the track 21 through the reinforcing protrusion 962 of the traction
projection 582 of
the next traction row 83,1; etc.
In some embodiments, the traction projections 581-58T may reduce power
consumption
to move the track 21 and/or noise generation by the track 21.
For example, in some embodiments, the track 21 may consume less power to move
at
a given speed than if the lower lateral ones of the tractions projections 581-
58T were as
tall as the higher central ones of the traction projections 581-58T but the
track 21 was
otherwise identical. For instance, Figure 9 shows that, in some embodiments,
the power
consumption to move the track 21 a given speed, such as between 40 miles per
hour
(mph) and 110 mph, may be no more than 95%, in some cases no more than 90%,
and
in some cases no more than 85% of the power consumption to move the track 21
at the
given speed than if the lower lateral ones of the tractions projections 581-
581- were as
tall as the higher central ones of the traction projections 581-58T but the
track 21 was
otherwise identical.
As another example, in some embodiments, the track 21 may generate less noise
when
moving at a given speed than if the lower lateral ones of the tractions
projections 581-
58T were as tall as the higher central ones of the traction projections 581-
58T but the
21
CA 2980208 2017-09-22
track 21 was otherwise identical. For instance, Figure 10 shows that, in some
embodiments, a sound level when the track 21 is moving at a given speed, such
as
between 40 miles per hour (mph) and 110 mph, may be at least 0.5 dBA (A-
weighted
decibels), in some cases at least 0.7 dBA, in some cases at least 0.9 dBA and
in some
cases even more decibels less than if the lower lateral ones of the tractions
projections
581-58T were as tall as the higher central ones of the traction projections
581-581- but the
track 21 was otherwise identical.
The track-engaging assembly 24 is configured to drive and guide the track 21
around
the track-engaging assembly 24.
Each of the drive wheels 221, 222 is rotatable by an axle for driving the
track 21. That is,
power generated by the prime mover 15 and delivered over the powertrain 12 of
the
snowmobile 10 rotates the axle, which rotates the drive wheels 221, 222, which
impart
motion of the track 21. In this embodiment, each drive wheel 22, comprises a
drive
sprocket engaging some of the drive/guide lugs 341-34D of the inner side 25 of
the track
21 in order to drive the track 21. In other embodiments, the drive wheel 22,
may be
configured in various other ways. For example, in embodiments where the track
21
comprises drive holes, the drive wheel 22, may have teeth that enter these
holes in
order to drive the track 21. As yet another example, in some embodiments, the
drive
wheel 22, may frictionally engage the inner side 25 of the track 21 in order
to frictionally
drive the track 21. The drive wheels 221, 222 may be arranged in other
configurations
and/or the track system 14 may comprise more or less drive wheels (e.g., a
single drive
wheel, more than two drive wheels, etc.) in other embodiments.
The idler wheels 261, 262, 281-286, 301, 302 are not driven by power supplied
by the
prime mover 15, but are rather used to do at least one of guiding the track 21
as it is
driven by the drive wheels 221, 222, tensioning the track 21, and supporting
part of the
weight of the snowmobile 10 on the ground via the track 21. More particularly,
in this
embodiment, the rear idler wheels 261, 262 are trailing idler wheels that
maintain the
track 21 in tension, guide the track 21 as it wraps around them, and can help
to support
22
CA 2980208 2017-09-22
part of the weight of the snowmobile 10 on the ground via the track 21. The
lower roller
wheels 281-286 roll on the inner side 25 of the track 21 along the bottom run
66 of the
track 21 to apply the bottom run 66 on the ground. The upper roller wheels
301, 302 roll
on the inner side 25 of the track 21 along the top run 65 of the track 21 to
support and
guide the top run 65 as the track 21 moves. The idler wheels 261, 262, 261-
266, 301, 302
may be arranged in other configurations and/or the track assembly 14 may
comprise
more or less idler wheels in other embodiments.
The frame 23 of the track system 14 supports various components of the track-
engaging assembly 24, including, in this embodiment, the idler wheels 261,
262, 281-286,
301, 302. More particularly, in this embodiment, the frame 23 comprises an
elongate
support 62 extending in the longitudinal direction of the track system 14
along the
bottom run 66 of the track 21 and frame members 491-49F extending upwardly
from the
elongate support 62.
The elongate support 62 comprises rails 441, 442 extending in the longitudinal
direction
of the track system 14 along the bottom run 66 of the track 21. In this
example, the idler
wheels 261, 262, 281-286 are mounted to the rails 441, 442. In this
embodiment, the
elongate support 62 comprises the sliding surfaces 771, 772 for sliding on the
inner side
25 of the track 21 along the bottom run 66 of the track 21. Thus, in this
embodiment, the
idler wheels 261, 262, 281-286 and the sliding surfaces 771, 772 of the
elongate support
62 can contact the bottom run 66 of the track 21 to guide the track 21 and
apply it onto
the ground for traction. In this example, the sliding surfaces 771, 772 can
slide against
the inner surface 32 of the carcass 35 and can contact respective ones of the
drive/guide lugs 341-34D to guide the track 21 in motion. Also, in this
example, the
sliding surfaces 771, 772 are curved upwardly in a front region of the track
system 14 to
guide the track 21 towards the drive wheels 221, 222.
In this embodiment, the elongate support 62 comprises sliders 331, 332 mounted
to
respective ones of the rails 441, 442 and comprising respective ones of the
sliding
surfaces 771, 772. In this embodiment, the sliders 331, 332 are mechanically
interlocked
23
CA 2980208 2017-09-22
with the rails 441, 442. In other embodiments, instead of or in addition to
being
mechanically interlocked with the rails 441, 442, the sliders 331, 332 may be
fastened to
the rails 441, 442. For example, in some embodiments, the sliders 331, 332 may
be
fastened to the rails 441, 442 by one or more mechanical fasteners (e.g.,
bolts, screws,
etc.), by an adhesive, and/or by any other suitable fastener.
In some examples, each slider 33, may comprise a low-friction material which
may
reduce friction between its sliding surface 77, and the inner side 25 of the
track 21. For
instance, the slider 33, may comprise a polymeric material having a low
coefficient of
friction with the rubber of the track 21. For example, in some embodiments,
the slider
33; may comprise a thermoplastic material (e.g., a Hifax0 polypropylene). The
slider 33,
may comprise any other suitable material in other embodiments. For instance,
in some
embodiments, the sliding surface 77, of the slider 33, may comprise a coating
(e.g., a
polytetrafluoroethylene (PTFE) coating) that reduces friction between it and
the inner
side 25 of the track 21, while a remainder of the slider 33, may comprise any
suitable
material (e.g., a metallic material, another polymeric material, etc.).
While in embodiments considered above the sliding surface 77, is part of the
slider 33,
which is separate from and mounted to each rail 44, in other embodiments, the
sliding
surface T7, may be part of the rail 44,. That is, the sliding surface 77; may
be integrally
formed (e.g., molded, cast, or machined) as part of the rail 44,.
The frame members 491-49F extend upwardly from the elongate support 62 to hold
the
upper roller wheels 301, 302 such that the upper roller wheels 301, 302 roll
on the inner
side 25 of the track 21 along the top run 65 of the track 21.
The track-engaging assembly 24 may be implemented in any other suitable way in
other
embodiments.
24
CA 2980208 2017-09-22
While in embodiments considered above the track system 14 is part of the
snowmobile
10, a track system including a track constructed according to principles
discussed
herein may be used as part of other off-road vehicles in other embodiments.
For example, in some embodiments, as shown in Figure 15, a snow bike 310
comprises
a frame 311, a powertrain 312, a ski system 317, a track system 314 including
a track
321, a seat 318, and a user interface 320 which enables a user to ride, steer
and
otherwise control the snow bike 310, and the track 321 may be constructed
according to
principle discussed herein in respect of the track 21.
In this embodiment, as shown in Figure 16, the snow bike 310 is a motorcycle
equipped
with the ski system 317 mounted in place of a front wheel 302 of the
motorcycle 310
and the track system 314 mounted in place of a rear wheel 304 of the
motorcycle 310.
In this example, the track system 314 also replaces a rear suspension unit
(e.g., a
shock absorber and a swing arm) of the motorcycle. Basically, in this
embodiment, the
ski system 317 and the track system 314 are part of a conversion system 313
that
converts the motorcycle into a skied and tracked vehicle for travelling on
snow.
The powertrain 312 is configured for generating motive power and transmitting
motive
power to the track system 314 to propel the snow bike 310 on the ground. To
that end,
the powertrain 312 comprises a prime mover 315, which is a source of motive
power
that comprises one or more motors (e.g., an internal combustion engine, an
electric
motor, etc.). For example, in this embodiment, the prime mover 315 comprises
an
internal combustion engine. In other embodiments, the prime mover 315 may
comprise
another type of motor (e.g., an electric motor) or a combination of different
types of
motor (e.g., an internal combustion engine and an electric motor). The prime
mover 315
is in a driving relationship with the track system 314. That is, the
powertrain 312
transmits motive power from the prime mover 315 to the track system 314 in
order to
drive (i.e., impart motion to) the track system 314.
CA 2980208 2017-09-22
The seat 318 accommodates the user of the snow bike 310. In this case, the
seat 318 is
a straddle seat and the snow bike 310 is usable by a single person such that
the seat
318 accommodates only that person driving the snow bike 310. In other cases,
the seat
318 may be another type of seat, and/or the snow bike 310 may be usable by two
individuals, namely one person driving the snow bike 310 and a passenger, such
that
the seat 318 may accommodate both of these individuals (e.g., behind one
another).
The user interface 320 allows the user to interact with the snow bike 310 to
control the
snow bike 310. More particularly, in this embodiment, the user interface 320
comprises
an accelerator, a brake control, and a steering device comprising handlebars
322 that
are operated by the user to control motion of the snow bike 510 on the ground.
The user
interface 320 also comprises an instrument panel (e.g., a dashboard) which
provides
indicators (e.g., a speedometer indicator, a tachometer indicator, etc.) to
convey
information to the user.
The ski system 317 is disposed in a front 324 of the snow bike 310 to engage
the
ground and is turnable to steer the snow bike 310. To that end, the ski system
14 is
turnable about a steering axis of the snow bike 310. The ski system 317
comprises a ski
328 to slide on the snow and a ski mount 330 that connects the ski 328 to a
front
steerable member 332 of the snow bike 310. In this embodiment where the snow
bike
310 is a motorcycle and the ski system 317 replaces the front wheel 302 of the
motorcycle, the front steerable member 332 comprises a front fork 334 of the
snow bike
310 that would otherwise carry the front wheel 302.
The ski 328 is a sole ski of the snow bike 310. That is, the snow bike 310 has
no other
ski. Notably, the ski 328 is disposed in a center of the snow bike 310 in a
widthwise
direction of the snow bike 310. In this embodiment in which the snow bike 310
is a
motocycle and the ski system 317 replaces the front wheel 302 of the
motorcycle, the
ski 328 contacts the ground where the front wheel 302 would contact the
ground.
26
CA 2980208 2017-09-22
Any feature described herein with respect to the track system 14 of the
snowmobile 10,
including its track 21, may be applied to the track system 314 of the snow
bike 310,
including its track 321.
As another example, in some embodiments, as shown in Figures 11-14, an ATV 210
comprises a set of track systems 2141-2144 providing traction to the ATV on
the ground,
where each of the track systems 2141-2144 comprises a track 221 that may be
constructed according to principle discussed herein in respect of the track
21.
The ATV 210 comprises a prime mover 212 in a driving relationship with the
track
systems 2141-2144 via the ATV's powertrain, a seat 218, and a user interface
220,
which enable a user of the ATV 210 to ride the ATV 210 on the ground. In this
case, the
seat 218 is a straddle seat and the ATV 210 is usable by a single person such
that the
seat 218 accommodates only that person driving the ATV 210. In other cases,
the seat
218 may be another type of seat, and/or the ATV 210 may be usable by two
individuals,
namely one person driving the ATV 210 and a passenger, such that the seat 218
may
accommodate both of these individuals (e.g., behind one another or side-by-
side) or the
ATV 210 may comprise an additional seat for the passenger. For example, in
other
embodiments, the ATV 210 may be a side-by-side ATV, sometimes referred to as a
"utility terrain vehicle" or "UTV". The user interface 220 comprises a
steering device
operated by the user to control motion of the ATV 210 on the ground. In this
case, the
steering device comprises handlebars. In other cases, the steering device may
comprise a steering wheel or other type of steering element. Each of the front
track
systems 2141, 2142 is pivotable about a steering axis of the ATV 210 in
response to
input of the user at the handlebars in order to steer the ATV 210 on the
ground.
In this embodiment, each track system 214, is mounted in place of a ground-
engaging
wheel 213, that may otherwise be mounted to the ATV 210 to propel the ATV 210
on the
ground. That is, the ATV 210 may be propelled on the ground by four ground-
engaging
wheels 2131-2134 with tires instead of the track systems 2141-2144. Basically,
in this
embodiment, the track systems 2141-2144 may be used to convert the ATV 210
from a
27
CA 2980208 2017-09-22
wheeled vehicle into a tracked vehicle, thereby enhancing its traction and
floatation on
the ground.
Any feature described herein with respect to the track system 14 of the
snowmobile 10,
including its track 21, may be applied to a track system 214, of the ATV 210,
including
its track 221.
The snowmobile 10, the snow bike 310 and the ATV 210 considered above are
examples of tracked recreational vehicles. While they can be used for
recreational
purposes, such tracked recreational vehicles may also be used for utility
purposes in
some cases.
In other embodiments, a track system constructed according to principles
discussed
herein may be used as part of an agricultural vehicle (e.g., a tractor, a
harvester, etc.),
as part of a construction vehicle, forestry vehicle or other industrial
vehicle, or as part of
a military vehicle.
Certain additional elements that may be needed for operation of some
embodiments
have not been described or illustrated as they are assumed to be within the
purview of
those of ordinary skill in the art. Moreover, certain embodiments may be free
of, may
lack and/or may function without any element that is not specifically
disclosed herein.
Any feature of any embodiment discussed herein may be combined with any
feature of
any other embodiment discussed herein in some examples of implementation.
Although various embodiments and examples have been presented, this was for
the
purpose of describing, but not limiting, the invention. Various modifications
and
enhancements will become apparent to those of ordinary skill in the art and
are within
the scope of the invention, which is defined by the appended claims.
28
CA 2980208 2017-09-22
