Patent Description:
The present technology relates generally to track systems for vehicles, and more particularly to tracks and wheels for heavy vehicles, including agricultural vehicles.

Certain vehicle types, such as, for example, industrial vehicles (e.g., harvesters, tractors, bulldozers, loaders etc.), military vehicles (e.g., tanks, carriers, etc.) and off-road vehicles (e.g., all terrain vehicles, utility task vehicles, etc.) are used to operate over ground surfaces that are soft, slippery and/or uneven (e.g., soil, mud, sand, rocks, debris, ice, snow, etc.).

Conventionally, such vehicles have had large wheels equipped with tires. Under certain conditions, such tires may provide insufficient traction when such vehicles operate on some ground surfaces and, as these vehicles are generally heavy, the ground surface may yield under the pressure exerted by the tires, as the weight of the vehicles is concentrated onto small areas.

In order to reduce the aforementioned drawbacks, to increase traction and to enhance stability of the vehicles, track systems were developed to be used in place of at least some of the tire-equipped wheels typically used on such vehicles. Track systems are equipped with tracks designed in accordance with the type of vehicle on which the track system is going to be installed.

For example, <CIT> describes a track for traction of an off-road vehicle such as an agricultural vehicle, a construction vehicle, a snowmobile, or another vehicle operable off-road. The track is mountable around a track-engaging assembly comprising a drive wheel, idler wheel assemblies and support wheel assemblies. The track is elastomeric to be flexible and wrapped around the track-engaging assembly. The track comprises a wheel-facing side for facing the wheels of the track-engaging assembly. The wheel-facing side includes a plurality of drive lugs and/or guide lugs projecting from the wheel-facing side for engaging the drive wheel, the idler wheel assemblies and the support wheel assemblies. The idler and support wheel assemblies have laterally spaced-apart wheels engaging the wheel-facing side of the endless track on either side of the drive/guide lugs in order to prevent the track from being dismounted from the track engaging assembly. The track further has a ground-facing side configured for engaging the ground, and a plurality of traction projections projecting from the ground-facing side. The document <CIT> discloses a track and wheels for a track system.

It is known in the art that the drive/guide lugs provided on the wheel-facing side of the track are subj ected to the repeated passage of the idler and support wheels, which creates a zone of relatively high pressure in the traction projection underlying the wheels, and consequently, a high temperature elevation in said traction projection. Furthermore, another issue is that the edge of the idler and support wheels near the drive/guide lugs creates a high shear stress in the track at the base of said drive/guide lugs.

These two effects typically significantly reduce the durability of the endless track by either overheating at least some of the materials forming the endless track (such as rubber-based materials) under the idler and/or support wheels, and/or by initiating cracks near the base of drive/guide lugs that will eventually propagate under the drive/guide lugs and weaken the drive/guide lugs until they are no longer strong enough to hold the driving force induced by the drive wheel. A non-reversible failure (i.e. delamination) commonly occurs at this stage.

Different solutions have been developed over time to mitigate these issues. Solutions include reinforcing the drive/guide lugs, especially with reinforcing members extending their base footprint, either inside or outside the carcass of the endless track. Efforts have also been made to add relatively soft material (e.g. rubber) on the external surface of the support wheels to reduce the stress induced to the region of the wheel-facing side of the endless track adjacent the bases of the drive/guide lugs. However, the load/pressure distribution still is not distributed evenly enough in these regions of the endless track. Even if the endless track or its drive/guide lugs are reinforced, the above-mentioned features still do not mitigate the issues of premature wear of the endless track mentioned above to a satisfying degree.

Therefore, there remains a desire for improvements in the design and configuration of components of track systems for further mitigating at least some of the aforementioned issues.

Prior art tracks, such as the example prior art tracks described above, have a number of drawbacks. In one aspect, where tracks are implemented with heavy vehicles, such as agricultural vehicles (tractors, harvesters, etc.), changes to features and aspects of the components of the track system, including changes that may at least at a first glance appear to persons who are not skilled in the art to be trivial, may in fact have technical implications for such vehicles.

In accordance with one aspect of the present technology, there is provided a track for a track system having a plurality of wheels for supporting the track on a ground surface, the track system being configured to support a nominal load, the track including an endless elastomeric carcass having a wheel-facing side for engaging the plurality of wheels, and a ground-facing side opposite the wheel-facing side for engaging the ground surface, the endless elastomeric carcass being resiliently deformable, a plurality of lugs projecting from the wheel-facing side, each lug of the plurality of lugs having a base and a side wall extending from the base, the base being distanced from the ground-facing side by a first distance, the wheel-facing side defining a wheel path on which the plurality of wheels rolls on, the wheel path having a first track side portion extending adjacent the bases of at least some lugs of the plurality of lugs, a second track side portion opposite the first track side portion, and an intermediate track portion located between the first and second track side portions, the intermediate track portion being distanced from the ground-facing side by a second distance, in response to one wheel of the plurality of wheels rolling on the wheel path and the track system supporting a first load being smaller than the nominal load, the track is resiliently deformed under the wheel and the second distance is greater than the first distance, and in response to one wheel of the plurality of wheels rolling on the wheel path and the track system supporting a second load being equal or greater than the nominal load, the track is further resiliently deformed under the wheel and the second distance is substantially equal to or smaller than the first distance.

In some embodiments, the first track side portion is distanced from the ground-facing side by a third distance, the second track side portion is distanced from the ground-facing side by a fourth distance, the intermediate track portion defines a track apex being distanced from the ground-facing side by the second distance being greater than at least one of the first, third and fourth distances.

In some embodiments, the second distance is greater than the third and fourth distances.

In some embodiments, the track apex is located closer to the first track side portion than the second track side portion.

In some embodiments, a cross-section of the elastomeric carcass at the wheel path has a shape being one of an arcuate shape, a V-shape, a cosine shape, a sine shape, a truncated triangle shape, a dome shape, and a trapezoidal shape.

In some embodiments, the base further includes a fillet extending between the side wall and the first track side portion of the wheel path, the fillet having a bottom, and the first distance extends between the bottom of the fillet and the ground-facing side of the track.

In some embodiments, at least one wheel of the plurality of wheels has a flange for engaging the side wall of at least one lug of the plurality of lugs, in response to the track system supporting the first load and the at least one wheel rolling on the wheel path, a first region of the side wall of the at least one lug is engageable by the flange, and in response to the track system supporting the second load and the at least one wheel rolling on the wheel path, the first region and a second region of the side wall of the at least one lug is engageable by the flange.

In some embodiments, the base defines an undercut extending between the side wall and the first track side portion of the wheel path, the undercut having a bottom, and the first distance extends between the bottom of the undercut and the ground-facing side of the track.

In some embodiments, the base further defines a recess extending laterally toward a lateral center of the track further than at least a portion of the side wall.

In accordance with another aspect of the present technology, there is also provided a wheel for a track system, the track system being configured to support a nominal load and having an endless track having a resiliently deformable, elastomeric carcass having a ground-facing side and a wheel-facing side opposite the ground-facing side, the wheel being configured for rolling on a wheel path defined on the wheel-facing side of the endless track, the wheel including a hub portion defining a rotation axis of the wheel, and a resilient annular rim portion connected to the hub portion, the resilient annular rim portion having an engagement surface extending around the rotation axis and including a first wheel side portion being distanced from the rotation axis by a first distance, a second wheel side portion opposite the first wheel side portion, the second wheel side portion being distanced from the rotation axis by a second distance, and an intermediate wheel portion located between the first and second wheel side portions, the intermediate wheel portion being distanced from the rotation axis by a third distance, in response to the wheel rolling on the wheel path and the track system supporting a first load being smaller than the nominal load, at least one of the annular rim portion and the endless track is resiliently deformed and the third distance is greater than at least one of the first and second distances, and in response to the wheel rolling on the wheel path and the track system supporting a second load being equal or greater than the nominal load, the annular rim portion and the endless track are resiliently deformed further and the third distance is substantially equal to or smaller than at least one of the first and second distances.

In some embodiments, in response to the wheel rolling on the wheel path and the track system supporting the first load, the third distance is greater than the first and second distances.

In some embodiments, the wheel further includes a flange connected to the resilient annular rim portion, the flange being configured for engaging a side wall of at least one lug of a plurality of lugs projecting from the wheel-facing side of the endless track, in response to the track system supporting the first load and the wheel rolling on the wheel path, the flange of the wheel is engageable to a first region of the side wall of the at least one lug, and in response to the track system supporting the second load and the wheel rolling on the wheel path, the flange of the wheel is engageable to the first region and a second region of the side wall of the at least one lug.

In some embodiments, the intermediate wheel portion defines a wheel apex, and the third distance extends between the wheel apex and the rotation axis.

In some embodiments, the wheel apex is located closer to the first wheel side portion than the second wheel side portion.

In accordance with yet another aspect of the present technology, there is provided a track system for a vehicle, the track system being configured to support a nominal load, the track system including an endless track having a resiliently deformable elastomeric carcass having a wheel-facing side defining a wheel path and a ground-facing side opposite the wheel-facing side, the wheel path having a first track side portion, a second track side portion opposite the first track side portion, and an intermediate track portion located between the first and second track side portions, the intermediate track portion extending further away from the ground-facing side than the first and second side track portions, and a track-engaging assembly including a wheel configured for rolling on the wheel path, the wheel having a hub portion defining a rotation axis of the wheel and a resilient annular rim portion connected to the hub portion, the resilient annular rim portion having an engagement surface extending around the rotation axis, the engagement surface having a first wheel side portion, a second wheel side portion opposite the first wheel side portion, and an intermediate wheel portion located between the first and second wheel side portions, the intermediate wheel portion extending further away from the rotation axis than the first and second wheel side portions, in response to the wheel rolling on the wheel path and the track system supporting a first load being smaller than the nominal load, at least one of the endless track and the annular rim portion is resiliently deformed, the intermediate track portion extends further away from the ground-facing side than the first and second track side portions, and the intermediate wheel portion extends further away from the rotation axis than the first and second wheel side portions, and in response to the wheel rolling on the wheel path and the track system supporting a second load being equal or greater than the nominal load, the endless track and the annular rim portion are resiliently deformed further, the intermediate track portion extends closer to ground-facing side of the endless track, and the intermediate wheel portion extends closer to the rotation axis of the wheel.

In some embodiments, in response to the wheel rolling on the wheel path and the track system supporting the second load, the intermediate track portion is distanced from the ground-facing side by a first distance being substantially equal to a second distance extending between one of the first and second track side portions and the ground-facing side.

In some embodiments, in response to the wheel rolling on the wheel path and the track system supporting the second load, the intermediate wheel portion is distanced from the rotation axis by a third distance being substantially equal to a fourth distance extending between one of the first and second wheel side portions and the rotation axis of the wheel.

In some embodiments, the track further includes a plurality of lugs projecting from the wheel-facing side of the track, each lug of the plurality of lugs having a base and a side wall extending from the base, the base having a bottom, and in response to the wheel rolling on the wheel path and the track system supporting the second load, the intermediate track portion is distanced from the ground-facing side by a fifth distance being substantially equal to or smaller than a sixth distance extending between the bottom of the base and the ground-facing side of the endless track.

In some embodiments, a cross-section of at least one of the elastomeric carcass at the wheel path and the resilient annular rim portion has a shape being one of an arcuate shape, a V-shape, a cosine shape, a sine shape, a truncated triangle shape, a dome shape, and a trapezoidal shape.

For purposes of the present application, terms related to spatial orientation when referring to a track system and components in relation to a vehicle equipped with the track system, such as "vertical", "longitudinal", "lateral", "horizontal", "forwardly", "rearwardly", "left", "right", "above" and "below", are as they would be understood by a driver of the vehicle sitting thereon in an upright driving position, with the vehicle steered straight-ahead and being at rest on flat, level ground. Also for clarity, the present application uses the terms "down" and "downward" to indicate a direction, for example of forces, that is parallel to and is in the direction of the force of gravity.

Implementations of the present technology each have at least one of the above-mentioned object and/or aspects, but do not necessarily have all of them. It should be understood that some aspects of the present technology that have resulted from attempting to attain the above-mentioned object may not satisfy this object and/or may satisfy other objects not specifically recited herein.

Additional and/or alternative features, aspects, and advantages of implementations of the present technology will become apparent from the following description, the accompanying drawings, and the appended claims.

In the present application, the expression "distance" is understood to be a shortest distance between two points or two surfaces. When the distances mentioned in the present application relate to the ground-facing side of the endless track, the surface of reference on the ground-facing side is a top wall of a traction projection projecting from the ground-facing side. Therefore, when the traction projection has a substantially flat profile and engages flat, level ground, the surface of reference corresponds to the interface between the flat, level ground and the top wall of the traction projection engaging the ground.

In the present application, the expression "substantially equal" is used herein to compare two quantities, explicitly or not, every quantity given herein is meant to refer to the actual given value, and it is also meant to refer to the approximation to such given value that would reasonably be inferred based on the ordinary skill in the art, including equivalents and approximations due to the experimental and/or measurement conditions for such given value. For example, the expression "substantially equal" in the context of comparing two quantities refers to a value or range that is within <NUM>%, preferably within <NUM>%, more preferably within <NUM>%, more preferably within <NUM>%, more preferably within <NUM>%, more preferably within <NUM>%, more preferably within <NUM>%, and more preferably within <NUM>% of the given value or range.

In the present application, the term "about" is used herein, explicitly or not, every quantity given herein is meant to refer to the actual given value, and it is also meant to refer to the approximation to such given value that would reasonably be inferred based on the ordinary skill in the art, including equivalents and approximations due to the experimental and/or measurement conditions for such given value. For example, the term "about" in the context of a given value or range refers to a value or range that is within <NUM>%, preferably within <NUM>%, more preferably within <NUM>%, more preferably within <NUM>%, more preferably within <NUM>%, more preferably within <NUM>%, more preferably within <NUM>%, and more preferably within <NUM>% of the given value or range.

Explanations and/or definitions of terms provided in the present application take precedence over explanations and/or definitions of these or similar terms that may be found in any documents incorporated herein by reference.

It should be noted that the Figures are not necessarily drawn to scale and some features shown in the Figures (for example, features such as a cross-section of the wheel path being of an arcuate shape) may be exaggerated relative to their possible "life" sizes and dimensions, in order to make these features clearly visible in the figures.

In <FIG>, there is presented a cross-section view of a track <NUM> and a wheel assembly <NUM> engaging a wheel-facing side <NUM> of the track <NUM> in accordance with technologies part of the prior art. The track <NUM> has drive lugs <NUM> defined in central portion thereof and projecting from the wheel-facing side <NUM>. The track <NUM> further has two wheel paths <NUM> on which wheels <NUM> of the wheel assembly <NUM> roll on. The wheel paths <NUM> are substantially flat and an engagement surface <NUM> of the wheels is also substantially flat. As mentioned above, this configuration of the wheel paths <NUM> and engagement surfaces <NUM> cause the edge <NUM> of the wheel <NUM> near the drive lug <NUM> to create a high shear stress at a base <NUM> of the drive lug <NUM> when the each wheel <NUM> rolls on the corresponding wheel path <NUM>.

The present technology is directed, among other things, at assisting in reducing the amount of shear stress near or at the base <NUM> of the drive lug <NUM>.

Different embodiments of present technology will now be described with reference to the accompanying drawings, which are provided herein for illustrative purposes only and are not intended to be limiting. Although the present technology is described in terms of specific illustrative embodiments, it is to be understood that the embodiments described herein are by way of example only and that the scope of the technology is not intended to be limited thereby. As a person skilled in the art would understand, various embodiments of the present technology may be of a greater complexity than what is described herein.

Referring to <FIG>, a track system <NUM> configured for being mounted to a right side of a vehicle (not shown) is presented. The track system <NUM> is configured for being driven in a forward travel direction indicated by arrow <NUM>. The track system <NUM> includes a frame assembly <NUM> operatively connected to the vehicle, a drive wheel <NUM> rotatably connected to the frame assembly <NUM> and being driven by a laterally extending drive shaft (not shown) of the vehicle, and a track engaging assembly <NUM> operatively connected to the frame assembly <NUM> for supporting and engaging an endless elastomeric track <NUM>. The track <NUM> includes an endless elastomeric carcass <NUM>.

The track engaging assembly <NUM> includes a leading idler wheel assembly <NUM>, a trailing idler wheel assembly <NUM>, and three support wheel assemblies 58a, 58b, 58c disposed longitudinally between the leading and trailing idler wheel assemblies <NUM>, <NUM>. The support wheel assemblies 58a, 58b, 58c include two laterally spaced support wheels <NUM>. The leading and trailing idler wheel assemblies <NUM>, <NUM> also include two laterally spaced idler wheels <NUM> being of greater size than the support wheels <NUM>.

The wheels <NUM>, <NUM> engage a wheel-facing side <NUM> of the endless track <NUM>. Two laterally spaced apart wheel paths <NUM> are defined on the wheel-facing side <NUM> of the track <NUM>. Drive lugs <NUM> project from a central region of the wheel-facing side <NUM> and extend between the wheel paths <NUM>. The drive lugs <NUM> are sized and configured for being engaged by teeth <NUM> provided on the drive wheel <NUM> for driving the track <NUM>. The drive lugs <NUM> also extend between the laterally spaced apart support wheels <NUM> and idler wheels <NUM> for maintaining a widthwise alignment of the track <NUM> relative to the wheels <NUM>, <NUM> and for preventing the track <NUM> from being dismounted from the track engaging assembly <NUM>.

It is contemplated that the track <NUM> could further include guide lugs for assisting maintaining a widthwise alignment of the track <NUM> relative to the wheels <NUM>, <NUM> and for preventing the track <NUM> from being dismounted from the track engaging assembly <NUM>. The present technology will be described with reference to the drive lugs <NUM>, but it is contemplated that the present technology could be implemented on tracks <NUM> also including guide lugs. The term "lug" employed hereinafter is thus contemplated to correspond to a drive lug or a guide lug.

Opposite the wheel-facing side <NUM>, the track <NUM> has a ground-facing side <NUM> configured for engaging the ground surface G (<FIG>). Traction projections <NUM> project from the ground-facing side <NUM> and form a tread <NUM> selected for the type of ground surface G on which the track system <NUM> is destined to travel. The traction projections <NUM> transfer driving forces that the track <NUM> receives from the vehicle through the drive wheel <NUM> into the ground surface G for driving the vehicle when the traction projections <NUM> engage the ground surface G. Each one of the traction projections <NUM> has a top wall <NUM> that is pressed against the ground surface G when the track system <NUM> is operated.

When the wheels <NUM>, <NUM> roll on their respective wheel path <NUM> for supporting the track <NUM>, the wheels <NUM>, <NUM> apply downward force to the endless track <NUM> and spread the load supported by the track system <NUM> on the ground surface G. The track system <NUM> is structured and configured to support a nominal load L1. In the present description, the nominal load L1 of the track system <NUM> corresponds to the track system <NUM> being attached to the vehicle with the track system <NUM> bearing its ordinary portion of the weight of the vehicle when the vehicle is at its tare weight, with no attachments at the front or rear and no payload in its container or tank. Should a payload be carried by the vehicle, the load supported by the track system <NUM> becomes greater than the nominal load L1. Such load will be referred hereinafter as L2. Conversely, should the track system <NUM> be disconnected from the vehicle and be self-supported on the ground surface G, the load supported by the track system <NUM> would correspond to the weight of the track system <NUM> and be smaller than the nominal load L1. Such load will be referred hereinafter as load L0.

Turning to <FIG>, the endless track <NUM> and one support wheel <NUM> will be further described. The description refers to one of the support wheels <NUM> from the support wheel assembly 58b, but it is contemplated that the following description could apply to any one of the wheels <NUM>, <NUM> of the track system <NUM>.

As best seen in <FIG>, the carcass <NUM> has a substantially rectangular widthwise cross-section <NUM> that is positioned such that when the track <NUM> is being driven and the vehicle drives over substantially planar ground surface G, the substantially rectangular widthwise cross-section <NUM> of the carcass <NUM> is substantially parallel to that ground surface G. The carcass <NUM> is flexible and resiliently deformable so as to be wrapped around the track engaging assembly <NUM> and be resiliently deformed in response to the wheels <NUM>, <NUM> rolling on their respective wheel path <NUM> and applying a load on the endless track <NUM>.

Referring to <FIG> and <FIG>, a base <NUM> is defined on either side of each one of the lugs <NUM>. The base <NUM> corresponds to the region where the wheel path <NUM> ends and where the lug <NUM> projects from the carcass <NUM>. A side wall <NUM> extends from the base <NUM> and vertically away from the carcass <NUM>. In the present embodiment, the sidewall <NUM> has different regions 94a, 94b, 94c that are engageable by the wheels <NUM>, <NUM> under certain conditions, as will be described further below. In the present embodiment, the base <NUM> has a fillet <NUM> extending between the region 94a of the side wall <NUM> and a track side portion <NUM> of the wheel path <NUM>. The fillet <NUM> has a bottom <NUM> being distanced from the top wall <NUM> of the opposite traction projection <NUM> by a distance <NUM> (<FIG>) when the load L0 is applied by the wheel <NUM>.

Still referring to <FIG> and <FIG>, the wheel path <NUM> on which the support wheel <NUM> rolls on will be further described. The wheel path <NUM> has the track side portion <NUM> extending adjacent the bases <NUM> of the lugs <NUM>. The track side portion <NUM> is distanced from the top wall <NUM> of the opposite traction projection <NUM> by a distance <NUM>. Another track side portion <NUM> extends opposite the track side portion <NUM>. The track side portion <NUM> is distanced from the top wall <NUM> of the opposite traction projection <NUM> by a distance <NUM>. In the present embodiment, distance <NUM> is substantially equal to distance <NUM>, but they could differ in other embodiments. For example, distance <NUM> could be larger than distance <NUM>. In other embodiments, distance <NUM> could be smaller than distance <NUM>.

An intermediate track portion <NUM> is located between the track side portions <NUM>, <NUM>. As best seen in <FIG>, the intermediate track portion <NUM> defines a track apex <NUM> in a central region thereof. It is contemplated that the track apex <NUM> could be located closer to one of the track side portions <NUM>, <NUM> in some embodiments, which could assist in spreading the load applied by the wheel <NUM> away from the base <NUM> of the lug <NUM>. The track apex <NUM> is distanced from the top wall <NUM> of the opposite traction projection <NUM> by a distance <NUM>. Distance <NUM> is greater than distance <NUM> and greater than distance <NUM>. The cross-section of the carcass <NUM> at the wheel path <NUM> is arcuate and has the intermediate track portion <NUM> and the track side portions <NUM>, <NUM> define a convex profile best seen in <FIG>. It is contemplated that, in other embodiments, the intermediate track portion <NUM> and the track side portions <NUM>, <NUM> could be disposed relative to one another to define other shapes, such as a V-shape (<FIG>), a cosine shape (<FIG>), a sine shape (<FIG>), a truncated triangle shape (<FIG>), a dome shape (<FIG>), and a trapezoidal shape (<FIG>).

Still referring to <FIG> and <FIG>, the support wheel <NUM> has a hub portion <NUM> defining a rotation axis <NUM> of the support wheel <NUM>. The hub portion <NUM> is connectable to an axle assembly of the support wheel assembly 58b. A resilient annular rim portion <NUM> is connected to the hub portion <NUM>. The resilient annular rim portion <NUM> has an engagement surface <NUM> extending circumferentially around the rotation axis <NUM>. The engagement surface <NUM> includes a wheel side portion <NUM>, another wheel side portion <NUM> opposite the wheel side portion <NUM>, and an intermediate wheel portion <NUM> located between the wheel side portions <NUM>, <NUM>. The wheel side portions <NUM>, <NUM> and the intermediate wheel portion <NUM> are distanced from the rotation axis <NUM> by a distance <NUM> when the load L0 is applied, and the engagement surface <NUM> thus has a substantially flat profile.

Referring to <FIG>, since the track system <NUM> supports the load L0 and that the engagement surface <NUM> of the wheel <NUM> has a substantially flat profile, a gap <NUM> is defined between the track side portion <NUM> and the wheel side portion <NUM>, and a gap <NUM> is also defined between the track side portion <NUM> and the wheel side portion <NUM>. It is contemplated that in some embodiments, the gaps <NUM>, <NUM> could be absent when the load L0 is applied, depending on the profile of the cross-section of the carcass <NUM> at the wheel path <NUM>. The intermediate wheel portion <NUM> engages the intermediate track portion <NUM>, the intermediate wheel portion <NUM> and the intermediate track portion <NUM> are resiliently deformed and the wheel <NUM> transfers the load L0 through the carcass <NUM> to the opposite traction projection <NUM>. In this state, distance <NUM> is greater than distance <NUM>. It is contemplated that, in other embodiments, the intermediate wheel portion <NUM> could be not resiliently deformed by an appreciable amount when the load L0 is applied.

Referring to <FIG> where the track system <NUM> supports the load L1, the increased load L1 compared to the load L0 of the state presented in <FIG> and <FIG> causes the intermediate track portion <NUM> and the intermediate wheel portions <NUM> to be resiliently deformed further. In this state, the wheel side portion <NUM> engages the track side portion <NUM>, and the wheel side portion <NUM> engages the track side portion <NUM> such that no gaps are defined therebetween. The distance <NUM> is now reduced and is smaller than distance <NUM>. It is contemplated that, in other embodiments, the structure and composition of the carcass <NUM> and the annular rim portion <NUM> could be selected such that the distance <NUM> is substantially equal to distance <NUM>. It is contemplated that should the load L2 (as indicated in <FIG>) be supported by the track system <NUM>, the distance <NUM> could be even smaller in some embodiments. The distance <NUM> is also smaller than the distance <NUM> and smaller than the distance <NUM>. It is contemplated that the distance <NUM> could be substantially equal to the distance <NUM> and/or the distance <NUM> is some embodiments when the load L1 is applied.

The resilient deformation of the carcass <NUM> and the resilient annular rim portion <NUM> under the wheel <NUM> assists in distributing the load L1 applied by the wheel <NUM> away from the base <NUM> of the lug <NUM>, which in turn may assist in reducing the shear stress induced at the base <NUM>. In other words, the load distribution is more even across the wheel-facing side <NUM> of the track <NUM> and across the wheel path <NUM>, compared to having a zone of relatively high stress near the base <NUM> of the lug <NUM> due to the edge of the wheel side portion <NUM> inducing a high shear stress at this location. In some circumstances, the compression of the carcass <NUM> at the wheel path <NUM> results in a lateral compression at the base <NUM> of the lug <NUM>, as indicated by arrow <NUM> on <FIG>. Crack initiation and/or propagation is therefore mitigated at the base <NUM> and/or in the track side portion <NUM> since the resilient elastomeric material of the carcass <NUM> is compressed laterally toward the base <NUM> of the lug <NUM>. Furthermore, this configuration of the carcass <NUM> and the support wheel <NUM> may assist in reducing heat build up in the support wheel <NUM> and/or the track <NUM> under certain circumstances, which may improve the durability of the track <NUM>.

Referring now to <FIG>, a track <NUM> and a wheel <NUM> being other embodiments of the present technology and suitable for the track system <NUM> will be described. Several components of the track <NUM> and wheel <NUM> are the same or similar to the components of the track <NUM> and wheel <NUM> described above. Therefore, for simplicity, components of the track <NUM> and wheel <NUM> that are the same as or similar to those of the track <NUM> and wheel <NUM> have been labeled with the same reference numerals, but in the <NUM> series, and will not be described in detail unless otherwise mentioned.

The track <NUM> differs from the track <NUM> in that the distances <NUM>, <NUM> and <NUM> are substantially equal, and that the cross-section of the carcass <NUM> at the wheel path <NUM> has a substantially flat profile. The wheel <NUM> differs from the wheel <NUM> in that the resilient annular rim portion <NUM> has a different profile, at least when the load L0 is applied. The wheel side portion <NUM> is distanced from the rotation axis <NUM> by a distance <NUM>. The wheel side portion <NUM> is distanced from the rotation axis <NUM> by a distance <NUM>. In the present embodiment, distance <NUM> is substantially equal to distance <NUM>, but they could differ in other embodiments. The intermediate wheel portion <NUM> is distanced from the rotation axis <NUM> by a distance <NUM>. Distance <NUM> is greater than distance <NUM> and distance <NUM>. The intermediate wheel portion <NUM> defines a wheel apex <NUM>. In this embodiment, distance <NUM> extends between the wheel apex <NUM> and the rotation axis <NUM>. The cross-section of the resilient annular rim portion <NUM> is arcuate and has the intermediate wheel portion <NUM> and the wheel side portions <NUM>, <NUM> define a convex profile. It is contemplated that, in other embodiments, the intermediate wheel portion <NUM> and the wheel side portions <NUM>, <NUM> could be disposed relative to one another to define other shapes, such as a V-shape, a sine shape, a cosine shape, a truncated triangle, a dome shape, and a trapezoidal shape as presented in <FIG> respectively. In other embodiments, it is also contemplated that the wheel apex <NUM> could be located closer to one of the wheel side portions <NUM>, <NUM>. Such positioning of the wheel apex <NUM> could assist in spreading the load applied by the wheel <NUM> further away from the base <NUM> of the lug <NUM>.

Referring to <FIG>, since the track system <NUM> supports the load L0 and that the cross-section of the carcass <NUM> at the wheel path <NUM> has a substantially flat profile, a gap <NUM> is defined between the track side portion <NUM> and the wheel side portion <NUM>, and a gap <NUM> is also defined between the track side portion <NUM> and the wheel side portion <NUM>. The intermediate wheel portion <NUM> engages the intermediate track portion <NUM>, the intermediate wheel portion <NUM> and the intermediate track portion <NUM> are resiliently deformed and the wheel <NUM> transfers the load through the carcass <NUM> to the opposite traction projection <NUM>. In this state, the distance <NUM> is greater than distance <NUM> and greater than distance <NUM>. It is contemplated that, in other embodiments, the intermediate wheel portion <NUM> could be not resiliently deformed by an appreciable amount when the load L0 is applied.

Referring to <FIG> where the track system <NUM> supports the load L1, the increased load L1 compared to the load L0 of the state presented in <FIG> and <FIG> causes the intermediate wheel portion <NUM> and the intermediate track portion <NUM> to be resiliently deformed further. In this state, the wheel side portion <NUM> engages the track side portion <NUM>, and the wheel side portion <NUM> engages the track side portion <NUM> such that no gaps are defined. The distance <NUM> is now reduced to be substantially equal to distance <NUM> and distance <NUM>. It is contemplated that should the load L2 be supported by the track system <NUM>, the distance <NUM> could be smaller than distance <NUM> and/or distance <NUM> in some embodiments.

The resilient deformation of the carcass <NUM> and the annular rim portion <NUM> under the wheel <NUM> assists in distributing the load applied by the wheel <NUM> away from the base <NUM> of the lug <NUM>, which in turns may assist in reducing the shear stress induced at the base <NUM>. In other words, the load distribution is more even across the wheel-facing side <NUM> of the track <NUM> and across the wheel path <NUM>, compared to having a zone of relatively high stress near the base <NUM> of the lug <NUM> due to the edge of the wheel side portion <NUM> inducing a high shear stress at this location. In some circumstances, the compression of the carcass <NUM> at the wheel path <NUM> results in a lateral compression at the base <NUM> of the lug <NUM>, as indicated by arrow <NUM> on <FIG>. Crack initiation and/or propagation is therefore mitigated at the base <NUM> and/or in the track side portion <NUM> since the resilient elastomeric material of the carcass <NUM> is compressed laterally toward the base <NUM> of the lug <NUM>. Furthermore, the present configuration of the carcass <NUM> and the support wheel <NUM> may assist in reducing heat build up in the support wheel <NUM> and/or the track <NUM> under certain circumstances, which may improve the durability of the track <NUM>.

Referring now to <FIG>, the track <NUM> and the wheel <NUM> described above are combined in another embodiment of the present technology being suitable for the track system <NUM>. For simplicity, the same reference numerals as presented above for the track <NUM> and the wheel <NUM> respectively will be used, unless otherwise mentioned.

Referring to <FIG> and <FIG>, since the cross-section of the carcass <NUM> at the wheel path <NUM> and the cross-section of the resilient annular rim portion <NUM> have a convex profile and when the track system <NUM> supports the load L0, a gap <NUM> defined between the track side portion <NUM> and the wheel side portion <NUM> is greater than the gap <NUM> (<FIG>), and a gap <NUM> defined between the track side portion <NUM> and the wheel side portion <NUM> is greater than the gap <NUM>. The intermediate wheel portion <NUM> engages the intermediate track portion <NUM>, the intermediate wheel portion <NUM> and the intermediate track portion <NUM> are resiliently deformed and the wheel <NUM> transfers the load through the carcass <NUM> to the opposite traction projection <NUM>. In this state, distance <NUM> is greater than distance <NUM> and distance <NUM>, and distance <NUM> is greater than distance <NUM> and greater than distance <NUM>.

Referring to <FIG> where the track system <NUM> supports the load L1, the increased load L1 compared to the load L0 of the state presented in <FIG> and <FIG> causes the intermediate wheel portion <NUM> and the intermediate track portion <NUM> to be resiliently deformed further. In this state, the wheel side portion <NUM> engages the track side portion <NUM>, and the wheel side portion <NUM> engages the track side portion <NUM> such that the gaps <NUM>, <NUM> are no longer defined. The distance <NUM> is now reduced to be substantially equal to distance <NUM> and distance <NUM>. The intermediate wheel portion <NUM> thus extends closer to the rotation axis <NUM> in <FIG> than it does in <FIG> and <FIG>. It is contemplated that, in other embodiments, distance <NUM> could be substantially equal to distance <NUM> or distance <NUM> when the load L1 or L2 is applied. The distance <NUM> is also reduced to be substantially equal to distance <NUM> and distance <NUM>. It is contemplated that, in other embodiments, distance <NUM> could be substantially equal to distance <NUM> or distance <NUM> when the load L1 or L2 is applied. Distance <NUM> is also smaller than distance <NUM> when the load L1 is applied, but distance <NUM> could be substantially equal to distance <NUM> in some embodiments when the load L1 is applied. The intermediate track portion <NUM> thus extends closer to the top wall <NUM> of the opposite traction projection <NUM> on the ground-facing side <NUM> of the track <NUM> when the load L1 is applied than when the load L0 is applied (<FIG>).

The resilient deformation of the carcass <NUM> and the annular rim portion <NUM> under the wheel <NUM> assists in distributing the load applied by the wheel <NUM> away from the base <NUM> of the lug <NUM>, which in turn may assist in further reducing the shear stress induced at the base <NUM> compared to the embodiments shown in the <FIG>. The resilient deformation of the carcass <NUM> and the annular rim portion <NUM> under the wheel <NUM> assists in distributing the load applied by the wheel <NUM> away from the base <NUM> of the lug <NUM>, which in turn may assist in reducing the shear stress induced at the base <NUM>. In other words, the load distribution is more even across the wheel-facing side <NUM> of the track <NUM> and across the wheel path <NUM>, compared to having a zone of relatively high stress near the base <NUM> of the lug <NUM> due to the edge of the wheel side portion <NUM> inducing a high shear stress at this location. In some circumstances, the compression of the carcass <NUM> at the wheel path <NUM> results in a lateral compression at the base <NUM> of the lug <NUM>, as indicated by arrow <NUM> on <FIG>. Because of the combined effects of the convex profile of the annular rim portion <NUM> and the convex profile of the carcass <NUM> at the wheel path <NUM>, it is contemplated that, at least in some circumstances, the amount of lateral compression at the base <NUM> of the lug <NUM> is greater in this embodiment than in the other embodiments presented above for a same load applied by the wheel <NUM> to the track <NUM>. Crack initiation and/or propagation is therefore mitigated at the base <NUM> and/or in the track side portion <NUM> since the resilient elastomeric material of the carcass <NUM> is compressed laterally toward the base <NUM> of the lug <NUM>. Furthermore, the present configuration of the carcass <NUM> and the support wheel <NUM> may further assist in reducing heat build up in the support wheel <NUM> and/or the track <NUM> under certain circumstances, which may improve the durability of the track <NUM>.

Referring back to <FIG> and <FIG>, the wheels <NUM>, <NUM> have a flange <NUM>, <NUM> connected to the respective annular rim portion <NUM>, <NUM>. The flanges <NUM>, <NUM> extend adjacent the side walls <NUM>, <NUM> of the lugs <NUM>, <NUM>. When the wheels <NUM>, <NUM> roll on the wheel path <NUM>, <NUM> and support the load L0, the respective portions 94b, 1094b of the side walls <NUM>, <NUM> are engageable by the corresponding flange <NUM>, <NUM> for maintaining the track <NUM>, <NUM> aligned in the widthwise direction. When the wheels <NUM>, <NUM> roll on the wheel path <NUM>, <NUM> and support the load L1, the respective portions 94b, 94c, and 1094b, 1094c of the side walls <NUM>, <NUM> are engageable by the corresponding flange <NUM>, <NUM> for maintaining the track <NUM>, <NUM> aligned in the widthwise direction (<FIG> and <FIG>). In other words, when the load in increased, the flanges <NUM>, <NUM> are sized and configured to be engaged to a larger portion of the side walls <NUM>, <NUM> of the lugs <NUM>, <NUM>, which in turn reduces the amount of shear stress applied to the base <NUM>, <NUM> of the lugs <NUM>, <NUM> during operation of the track system <NUM> and improves the durability of the track <NUM>, <NUM>.

Referring now to <FIG>, a track <NUM> being another embodiment of the present technology and suitable for the track system <NUM> will be described. Several components of the track <NUM> are the same or similar to the components of the track <NUM> described above. Therefore, for simplicity, components of the track <NUM> that are the same as or similar to those of the track <NUM> have been labeled with the same reference numerals, but in the <NUM> series, and will not be described in detail unless otherwise mentioned.

In the track <NUM>, the wheel path <NUM> extends substantially flat between the track side portions <NUM>, <NUM> and <NUM>, and thus distances <NUM>, <NUM>, <NUM> are substantially equal. The base <NUM> of the lug <NUM> differs from the ones shown in the other embodiments in that the fillet <NUM> defines a bottom <NUM> having a distance <NUM> being smaller than distance <NUM>. The fillet <NUM> extends upwardly from the bottom <NUM> towards the track side portion <NUM> (toward the left side on <FIG>), creating a cross-section profile of the carcass <NUM> at the wheel path <NUM> this is also convex. It is contemplated that when a wheel having an annual rim portion with a flat profile (similar to the wheel <NUM>) rolls on the wheel path <NUM> and is supporting the load L1, distance <NUM> becomes substantially equal to distances <NUM>, <NUM>, <NUM>. The above-mentioned effects of lateral compression of the carcass towards the base <NUM> also appear, which in turn may assist in improving the durability of the track <NUM>.

Referring to <FIG>, a track <NUM> being another embodiment of the present technology and suitable for the track system <NUM> will be described. Several components of the track <NUM> are the same or similar to the components of the track <NUM> described above. Therefore, for simplicity, components of the track <NUM> that are the same as or similar to those of the track <NUM> have been labeled with the same reference numerals, but in the <NUM> series, and will not be described in detail unless otherwise mentioned.

In the track <NUM>, the track apex <NUM> is defined near the track side portion <NUM> instead of being defined at the intermediate track portion <NUM>. Distance <NUM> is thus greater than distance <NUM> and distance <NUM>, and is also greater than distance <NUM>. The track apex <NUM> is thus closer to the track side portion <NUM> than the track side portion <NUM>. An angle <NUM> defined between a horizontal plane <NUM> and the surface of the wheel path <NUM> extending between the track apex <NUM> and the bottom <NUM> is greater than an angle <NUM> defined between the horizontal plane <NUM> and the surface of the wheel path <NUM> extending between the track apex <NUM> and track side portion <NUM>. It is contemplated that when a wheel having an annual rim portion with a flat profile (similar to the wheel <NUM>) rolls on the wheel path <NUM> and is supporting the load L1, the above-mentioned effects of lateral compression of the carcass towards the base <NUM> also appear, which in turn may assist in improving the durability of the track <NUM>.

The track <NUM> has undercuts <NUM> defined in the base <NUM> of the lug <NUM>. Each undercut <NUM> defines a recess <NUM> extending inwardly towards a lateral center <NUM> of the track <NUM> further than the portion 5094a of the corresponding side wall <NUM>. Each undercut <NUM> has a bottom <NUM>, and the distance <NUM> extends between the bottom <NUM> of the undercut <NUM> and the ground-facing side of the track (represented by the top wall <NUM>). This configuration of the base <NUM> of the lug <NUM> may also assist in reducing the amount of shear stress induced at the base <NUM> of the lug <NUM> when wheels (not shown) roll on the wheel path <NUM> and support the load L1. This configuration of the base <NUM> of the lug <NUM> is contemplated to be used with any one of the configurations of the tracks and wheels presented above.

The track <NUM> has undercuts <NUM> defined in the base <NUM> of the lug <NUM> and in the track side portions <NUM> of the wheel paths <NUM>. Each undercut <NUM> defines a recess <NUM> extending inwardly towards a lateral center <NUM> of the track <NUM> further than the portion 6094a of the corresponding side wall <NUM>. A bottom <NUM> of each undercut <NUM> extends vertically below the intermediate track portion <NUM> and the track side portion <NUM>. The distance <NUM> is defined between the bottom <NUM> of the undercut <NUM> and the top wall <NUM> of the traction projection <NUM> of the track <NUM>. This configuration of the base <NUM> of the lug <NUM> may also assist in reducing the amount of shear stress induced at the base <NUM> of the lug <NUM> when wheels (not shown) roll on the wheel path <NUM> and support the load L1. This configuration of the base <NUM> of the lug <NUM> is also contemplated to be used with any one of the configurations of the tracks and wheels presented above.

The tracks <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, the wheels <NUM>, <NUM>, <NUM> and the track systems <NUM> implemented in accordance with some non-limiting embodiments of the present technology can be represented as presented in the following numbered clauses.

CLAUSE <NUM>: A track (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) for a track system (<NUM>) having a plurality of wheels (<NUM>, <NUM>, <NUM>) for supporting the track on a ground surface (G), the track system being configured to support a nominal load (L1), the track comprising an endless elastomeric carcass (<NUM>, <NUM>) having a wheel-facing side (<NUM>) for engaging the plurality of wheels, and a ground-facing side (<NUM>) opposite the wheel-facing side for engaging the ground surface, the endless elastomeric carcass being resiliently deformable, a plurality of lugs (<NUM>, <NUM>) projecting from the wheel-facing side, each lug of the plurality of lugs having a base (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and a side wall (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) extending from the base, the base being distanced from the ground-facing side by a first distance (<NUM>, <NUM>, <NUM>, <NUM>,<NUM>, <NUM>), the wheel-facing side defining a wheel path (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) on which the plurality of wheels rolls on, the wheel path having a first track side portion (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) extending adjacent the bases of at least some lugs of the plurality of lugs, a second track side portion (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) opposite the first track side portion, and an intermediate track portion (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) located between the first and second track side portions, the intermediate track portion being distanced from the ground-facing side by a second distance (<NUM>, <NUM>, <NUM>, <NUM>), in response to one wheel of the plurality of wheels rolling on the wheel path and the track system supporting a first load being smaller than the nominal load, the track is resiliently deformed under the wheel and the second distance is greater than the first distance, and in response to one wheel of the plurality of wheels rolling on the wheel path and the track system supporting a second load being equal or greater than the nominal load, the track is further resiliently deformed under the wheel and the second distance is substantially equal to or smaller than the first distance.

CLAUSE <NUM>: The track of clause <NUM>, wherein the first track side portion is distanced from the ground-facing side by a third distance (<NUM>, <NUM>, <NUM>, <NUM>), the second track side portion is distanced from the ground-facing side by a fourth distance (<NUM>, <NUM>, <NUM>, <NUM>), the intermediate track portion defines a track apex (<NUM>, <NUM>) being distanced from the ground-facing side by the second distance being greater than at least one of the first, third and fourth distances.

CLAUSE <NUM>: The track of clause <NUM>, wherein the second distance is greater than the third and fourth distances.

CLAUSE <NUM>: The track of clause <NUM> or <NUM>, wherein the track apex is located closer to the first track side portion than the second track side portion.

CLAUSE <NUM>: The track of any one of clauses <NUM> to <NUM>, wherein a cross-section (<NUM>) of the elastomeric carcass at the wheel path has a shape being one of an arcuate shape, a V-shape, a cosine shape, a sine shape, a truncated triangle shape, a dome shape, and a trapezoidal shape.

CLAUSE <NUM>: The track of any one of clauses <NUM> to <NUM>, wherein the base further comprises a fillet (<NUM>, <NUM>) extending between the side wall and the first track side portion of the wheel path, the fillet having a bottom (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and the first distance extends between the bottom of the fillet and the ground-facing side of the track.

CLAUSE <NUM>: The track of any one of clauses <NUM> to <NUM>, wherein at least one wheel of the plurality of wheels has a flange (<NUM>, <NUM>) for engaging the side wall of at least one lug of the plurality of lugs, in response to the track system supporting the first load and the at least one wheel rolling on the wheel path, a first region (94b, 1094b) of the side wall of the at least one lug is engageable by the flange, and in response to the track system supporting the second load and the at least one wheel rolling on the wheel path, the first region and a second region (94c, 1094c) of the side wall of the at least one lug is engageable by the flange.

CLAUSE <NUM>: The track of any one of clauses <NUM> to <NUM>, wherein the base defines an undercut (<NUM>, <NUM>) extending between the side wall and the first track side portion of the wheel path, the undercut having a bottom (<NUM>, <NUM>), and the first distance extends between the bottom of the undercut and the ground-facing side of the track.

CLAUSE <NUM>: The track of clause <NUM>, wherein the base further defines a recess (<NUM>, <NUM>) extending laterally toward a lateral center (<NUM>, <NUM>) of the track further than at least a portion of the side wall.

CLAUSE <NUM>: A wheel (<NUM>, <NUM>) for a track system (<NUM>), the track system being configured to support a nominal load (L1) and having an endless track (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) having a resiliently deformable, elastomeric carcass (<NUM>, <NUM>) having a ground-facing side (<NUM>) and a wheel-facing side (<NUM>) opposite the ground-facing side, the wheel being configured for rolling on a wheel path (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) defined on the wheel-facing side of the endless track, the wheel comprising a hub portion (<NUM>, <NUM>) defining a rotation axis (<NUM>, <NUM>) of the wheel, and a resilient annular rim portion (<NUM>, <NUM>) connected to the hub portion, the resilient annular rim portion having an engagement surface (<NUM>, <NUM>) extending around the rotation axis and including a first wheel side portion (<NUM>, <NUM>) being distanced from the rotation axis by a first distance (<NUM>, <NUM>), a second wheel side portion (<NUM>, <NUM>) opposite the first wheel side portion, the second wheel side portion being distanced from the rotation axis by a second distance (<NUM>, <NUM>), and an intermediate wheel portion (<NUM>, <NUM>) located between the first and second wheel side portions, the intermediate wheel portion being distanced from the rotation axis by a third distance (<NUM>, <NUM>), in response to the wheel rolling on the wheel path and the track system supporting a first load being smaller than the nominal load, at least one of the annular rim portion and the endless track is resiliently deformed and the third distance is greater than at least one of the first and second distances, and in response to the wheel rolling on the wheel path and the track system supporting a second load being equal or greater than the nominal load, the annular rim portion and the endless track are resiliently deformed further and the third distance is substantially equal to or smaller than at least one of the first and second distances.

CLAUSE <NUM>: The wheel of clause <NUM>, wherein, in response to the wheel rolling on the wheel path and the track system supporting the first load, the third distance is greater than the first and second distances.

CLAUSE <NUM>: The wheel of clause <NUM> or <NUM>, further comprising a flange (<NUM>, <NUM>) connected to the resilient annular rim portion, the flange being configured for engaging a side wall (<NUM>, <NUM>) of at least one lug (<NUM>, <NUM>) of a plurality of lugs projecting from the wheel-facing side of the endless track, wherein in response to the track system supporting the first load and the wheel rolling on the wheel path, the flange of the wheel is engageable to a first region (94b, 1094b) of the side wall of the at least one lug, and in response to the track system supporting the second load and the wheel rolling on the wheel path, the flange of the wheel is engageable to the first region and a second region (94c, 1094c) of the side wall of the at least one lug.

CLAUSE <NUM>: The wheel of any one of clauses <NUM> to <NUM>, wherein the intermediate wheel portion defines a wheel apex (<NUM>), and the third distance extends between the wheel apex and the rotation axis.

CLAUSE <NUM>: The wheel of clause <NUM>, wherein the wheel apex is located closer to the first wheel side portion than the second wheel side portion.

CLAUSE <NUM>: A track system (<NUM>) for a vehicle, the track system being configured to support a nominal load, the track system comprising an endless track (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) having a resiliently deformable elastomeric carcass (<NUM>, <NUM>) having a wheel-facing side (<NUM>) defining a wheel path (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and a ground-facing side (<NUM>) opposite the wheel-facing side, the wheel path having a first track side portion (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>), a second track side portion (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) opposite the first track side portion, and an intermediate track portion (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) located between the first and second track side portions, the intermediate track portion extending further away from the ground-facing side than the first and second side track portions, and a track-engaging assembly (<NUM>) including a wheel (<NUM>, <NUM>, <NUM>) configured for rolling on the wheel path, the wheel having a hub portion (<NUM>, <NUM>) defining a rotation axis (<NUM>, <NUM>) of the wheel and a resilient annular rim portion (<NUM>, <NUM>) connected to the hub portion, the resilient annular rim portion having an engagement surface (<NUM>, <NUM>) extending around the rotation axis, the engagement surface having a first wheel side portion (<NUM>, <NUM>), a second wheel side portion (<NUM>, <NUM>) opposite the first wheel side portion, and an intermediate wheel portion (<NUM>, <NUM>) located between the first and second wheel side portions, the intermediate wheel portion extending further away from the rotation axis than the first and second wheel side portions, in response to the wheel rolling on the wheel path and the track system supporting a first load being smaller than the nominal load, at least one of the endless track and the annular rim portion is resiliently deformed, the intermediate track portion extends further away from the ground-facing side than the first and second track side portions, and the intermediate wheel portion extends further away from the rotation axis than the first and second wheel side portions, and in response to the wheel rolling on the wheel path and the track system supporting a second load being equal or greater than the nominal load, the endless track and the annular rim portion are resiliently deformed further, the intermediate track portion extends closer to ground-facing side of the endless track, and the intermediate wheel portion extends closer to the rotation axis of the wheel.

CLAUSE <NUM>: The track system of clause <NUM>, wherein, in response to the wheel rolling on the wheel path and the track system supporting the second load, the intermediate track portion is distanced from the ground-facing side by a first distance (<NUM>, <NUM>) being substantially equal to a second distance (<NUM>, <NUM>, <NUM>, <NUM>) extending between one of the first and second track side portions and the ground-facing side.

CLAUSE <NUM>: The track system of clause <NUM>, wherein, in response to the wheel rolling on the wheel path and the track system supporting the second load, the intermediate wheel portion is distanced from the rotation axis by a third distance (<NUM>, <NUM>) being substantially equal to a fourth distance (<NUM>, <NUM>, <NUM>, <NUM>) extending between one of the first and second wheel side portions and the rotation axis of the wheel.

CLAUSE <NUM>: The track system of clause <NUM>, wherein the track further comprises a plurality of lugs (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) projecting from the wheel-facing side of the track, each lug of the plurality of lugs having a base (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and a side wall (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) extending from the base, the base having a bottom (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>), and in response to the wheel rolling on the wheel path and the track system supporting the second load, the intermediate track portion is distanced from the ground-facing side by a fifth distance (<NUM>, <NUM>) being substantially equal to or smaller than a sixth distance (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) extending between the bottom of the base and the ground-facing side of the endless track.

CLAUSE <NUM>: The track system of any one of clauses <NUM> to <NUM>, wherein a cross-section of at least one of the elastomeric carcass at the wheel path and the resilient annular rim portion has a shape being one of an arcuate shape, a V-shape, a cosine shape, a sine shape, a truncated triangle shape, a dome shape, and a trapezoidal shape.

Claim 1:
A track (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) for a track system (<NUM>) having a plurality of wheels (<NUM>, <NUM>, <NUM>) for supporting the track on a ground surface, the track system being configured to support a nominal load, the track comprising:
an endless elastomeric carcass (<NUM>, <NUM>) having a wheel-facing side (<NUM>) for engaging the plurality of wheels, and a ground-facing side (<NUM>) opposite the wheel-facing side for engaging the ground surface, the endless elastomeric carcass being resiliently deformable;
a plurality of lugs (<NUM>, <NUM>) projecting from the wheel-facing side, each lug of the plurality of lugs having a base (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and a side wall (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) extending from the base, the base being distanced from the ground-facing side by a first distance (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>);
the wheel-facing side defining a wheel path (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) on which the plurality of wheels rolls on, the wheel path having:
a first track side portion (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) extending adjacent the bases of at least some lugs of the plurality of lugs,
a second track side portion (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) opposite the first track side portion, and
an intermediate track portion (<NUM>, <NUM>, <NUM>), located between the first and second track side portions, the intermediate track portion being distanced from the ground-facing side by a second distance (<NUM>, <NUM>, <NUM>, <NUM>);
in response to one wheel of the plurality of wheels rolling on the wheel path and the track system supporting a first load being smaller than the nominal load, the track is resiliently deformed under the wheel and the second distance is greater than the first distance, and
in response to one wheel of the plurality of wheels rolling on the wheel path and the track system supporting a second load being equal or greater than the nominal load, the track is further resiliently deformed under the wheel and the second distance is substantially equal to or smaller than the first distance.