# US 11,999,419 B2 · Track system for traction of a vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,999,419 B2 - Document ID: US11999419B2 - Status: Granted - Kind: B2 - Application number: 16/063,102 - Filed: 2016-12-16 - Published: 2020-09-03 - Granted: 2024-06-04 - Earliest claimed: 2015-12-16 - Assignees: Camso Inc. - Applicants: Camso Inc. - Inventors: Ronald H. Thompson; Jeremie Zuchoski - Web page: https://patentgrep.com/patent/US11999419B2 ## CPC - B62D 55/065: Multi-track vehicles, i.e. more than two tracks {(soil-shifting machines E02F; mining machines E21C)} - B62D 55/10: Bogies; Frames (track-tensioning means B62D55/30) - B60C 7/107: {comprising lateral openings} - B60C 7/143: {having a lateral extension disposed in a plane parallel to the wheel axis} - B60C 7/146: {extending substantially radially, e.g. like spokes} - B60C 9/1807: {comprising fabric reinforcements} - B62D 55/04: with tracks and alternative ground wheels, e.g. changeable from endless track vehicle into wheeled vehicle and vice versa {(for multi-purpose tractors B62D49/0635)} - B62D 55/12: Arrangement, location, or adaptation of driving sprockets - B62D 55/14: Arrangement, location, or adaptation of rollers - B62D 55/202: {Wheel engaging parts; Wheel guides on links} - B62D 55/26: Ground engaging parts or elements {(tracks specially adapted for amphibious vehicles B60F3/0015)} - B62D 55/305: {acting on pivotably mounted idlers} - B62D 55/244: {Moulded in one piece, with either smooth surfaces or surfaces having projections, e.g. incorporating reinforcing elements} - B62D: MOTOR VEHICLES; TRAILERS (steering, or guiding on a desired track, of agricultural machines or implements A01B69/00; wheels, castors, axles, increasing wheel adhesion B60B; vehicle tyres, tyre inflation or tyre changing B60C; connections between vehicles of a train or the like B60D; vehicles for use on rail and road, amphibious or convertible vehicles B60F; suspension arrangements B60G; heating, cooling, ventilating or other air treating devices B60H; windows, windscreens, non-fixed roofs, doors or similar devices, protective coverings for vehicles not in use B60J; propulsion plant arrangements, auxiliary drives, transmissions, controls, instrumentation or dashboards B60K; electric equipment or propulsion of electrically-propelled vehicles B60L; power supply for electrically-propelled vehicles B60M; passenger accommodation not otherwise provided for B60N; adaptations for load transportation or to carry special loads or objects B60P; arrangement of signalling or lighting devices, the mounting or supporting thereof or circuits therefor, for vehicles in general B60Q; vehicles, vehicle fittings or vehicle parts not otherwise provided for B60R; servicing, cleaning, repairing, supporting, lifting, or manoeuvring, not otherwise provided for, B60S; brake arrangements, brake control systems or parts thereof B60T; air-cushion vehicles B60V; motor-cycles, accessories therefor B62J, B62K; testing of vehicles G01M) - B60C: VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES ## Abstract A track system for traction of a vehicle (e.g., an all-terrain vehicle (ATV), an agricultural vehicle, etc.) may be designed (e.g., may comprise non-pneumatic tires) to enhance its use or performance and/or that of the vehicle such as, for example, by being lightweight and/or by better handling loads, including, for instance, those resulting from track tension within the track system and/or from unevenness or other aspects of the ground, including encounters (e.g., impacts) with obstacles on the ground (e.g., rocks, portions of trees, debris, bumps, abrupt changes in ground level, etc.). The track system may comprise tension-based non-pneumatic tires. ## Claims ### Claim 1 A track system for traction of a vehicle, the track system comprising: a track for engaging the ground; and a track-engaging assembly for driving and guiding the track around the track-engaging assembly, the track-engaging assembly comprising: a drive wheel for driving the track; and a plurality of idler wheels spaced apart in a longitudinal direction of the track system, front and rear ones of the idler wheels guiding the track at front and rear ends of the track system, each idler wheel comprising a non-pneumatic tire that comprises: an annular beam configured to deflect at an area of contact of the non-pneumatic tire with the track and comprising an elastomeric material that constitutes at least a majority of the annular beam, the annular beam comprising a plurality of openings distributed and spaced from one another in a circumferential direction of the non-pneumatic tire, wherein each of the openings extends from a first lateral side of the non-pneumatic tire to a second lateral side of the non-pneumatic tire, and further comprising a plurality of interconnecting members, each interconnecting member extending between consecutive ones of the openings and extending continuously in the circumferential direction between the consecutive ones of the openings; and a plurality of spokes disposed radially inwardly of the annular beam and configured to resiliently deform under loading on the idler wheel such that respective ones of the spokes between an axis of rotation of the idler wheel and the area of contact of the non-pneumatic tire with the track are in compression and respective ones of the spokes between the axis of rotation of the idler wheel and a peripheral part of the idler wheel not in contact with the track are in tension. ### Claim 2 (depends on 1) The track system of claim 1, wherein each of the spokes is curved. ### Claim 3 (depends on 1) The track system of claim 1, wherein the annular beam is configured to deflect more by shearing than by bending when the idler wheel encounters an obstacle on the ground. ### Claim 4 (depends on 1) The track system of claim 1, wherein the non-pneumatic tire comprises a tread. ### Claim 5 (depends on 4) The track system of claim 4, wherein the elastomeric material of the annular beam is a first elastomeric material and the tread comprises a second elastomeric material different from the first elastomeric material. ### Claim 6 (depends on 1) The track system of claim 1, wherein a ratio of a width of the non-pneumatic tire over a width of the track is at least 0.2. ### Claim 7 (depends on 1) The track system of claim 1, wherein laterally-spaced ones of the idler wheels are spaced from one another in a widthwise direction of the track system. ### Claim 8 (depends on 7) The track system of claim 7, wherein a sum of widths of two of the laterally-spaced ones of the idler wheels corresponds to at least a majority of a width of the track. ### Claim 9 (depends on 1) The track system of claim 1, wherein a ratio of a mass of the idler wheel over an outer diameter of the idler wheel normalized by a width of the idler wheel is no more than 0.0005 kg/mm2. ### Claim 10 (depends on 1) The track system of claim 1, wherein a radial stiffness of the idler wheel is no more than 15 kgf/mm. ### Claim 11 (depends on 1) The track system of claim 1, wherein: the spokes extend from the annular beam to a hub of the idler wheel; and a ratio of a volume occupied by the spokes over a volume bounded by the annular beam and the hub of the idler wheel is no more than 15%. ### Claim 12 (depends on 1) The track system of claim 1, wherein an inner diameter of the non-pneumatic tire is no more than half of an outer diameter of the non-pneumatic tire. ### Claim 13 (depends on 1) The track system of claim 1, wherein the drive wheel is located between axes of rotation of the front and rear ones of the idler wheels in the longitudinal direction of the track system. ### Claim 14 (depends on 1) The track system of claim 1, wherein axes of rotation of the idler wheels are movable relative to an axis of rotation of the drive wheel when the track system moves on the ground. ### Claim 15 (depends on 1) The track system of claim 1, wherein mid-roller ones of the idler wheels are disposed between the front and rear ones of the idler wheels in the longitudinal direction of the track system. ### Claim 16 (depends on 15) The track system of claim 15, wherein each of the front and rear ones of the idler wheels is larger in diameter than a given one of the mid-roller ones of the idler wheels. ### Claim 17 (depends on 16) The track system of claim 16, wherein each of the front and rear ones of the idler wheels is wider than the given one of the mid-roller ones of the idler wheels in a widthwise direction of the track system. ### Claim 18 (depends on 1) A vehicle comprising the track system of claim 1. ### Claim 19 (depends on 1) The track system of claim 1, wherein a ratio of a radial stiffness of the idler wheel over an outer diameter of the idler wheel normalized by a width of the idler wheel is between 0.0001 kgf/mm3 and 0.0002 kgf/mm3. ### Claim 20 (depends on 1) The track system of claim 1, wherein a radial stiffness of the idler wheel is different under different types of loading on the idler wheel. ### Claim 21 (depends on 20) The track system of claim 20, wherein: a first one of the different types of loading on the idler wheel occurs when the track system is operated at lower speed and higher torque than when a second one of the different types of loading on the idler wheel occurs; and the radial stiffness of the idler wheel is greater under the first one of the different types of loading on the idler wheel than under the second one of the different types of loading on the idler wheel. ### Claim 22 (depends on 20) The track system of claim 20, wherein the tension of the track is greater in the first one of the different types of loading on the idler wheel than the second one of the different types of loading on the idler wheel. ### Claim 23 (depends on 22) The track system of claim 22, wherein the second one of the different types of loading on the idler wheel is associated with an impact on the track system. ### Claim 24 (depends on 1) The track system of claim 1, wherein a material of the non-pneumatic tire of a first one of the idler wheels is different from a material of the non-pneumatic tire of a second one of the idler wheels. ### Claim 25 (depends on 1) The track system of claim 1, wherein a material of the annular beam of the non-pneumatic tire of a first one of the idler wheels is different from a material of the annular beam of the non-pneumatic tire of a second one of the idler wheels. ### Claim 26 (depends on 1) The track system of claim 1, wherein a material of the spokes of the non-pneumatic tire of a first one of the idler wheels is different from a material of the spokes of the non-pneumatic tire of a second one of the idler wheels. ### Claim 27 (depends on 1) The track system of claim 1, wherein the non-pneumatic tire is free of any reinforcing layer running in a circumferential direction of the non-pneumatic tire. ### Claim 28 (depends on 1) The track system of claim 1, wherein a spacing of the openings in the circumferential direction of the non-pneumatic tire is less than a dimension of a given one of the openings in the circumferential direction of the non-pneumatic tire. ### Claim 29 (depends on 1) The track system of claim 1, wherein: each idler wheel comprises a hub disposed radially inwardly of the spokes; and the non-pneumatic tire is molded about the hub. ### Claim 30 (depends on 29) The system of claim 29, wherein a material of the hub is different from a material of the spokes. ### Claim 31 A track system for traction of a vehicle, the track system comprising: a track for engaging the ground; and a track-engaging assembly for driving and guiding the track around the track-engaging assembly, the track-engaging assembly comprising: a drive wheel for driving the track; front and rear idler wheels spaced apart in a longitudinal direction of the track system for guiding the track at front and rear ends of the track system; and mid-roller wheels disposed between the front and rear idler wheels in the longitudinal direction of the track system, each mid-roller wheel comprising a non-pneumatic tire and a hub, the non-pneumatic tire comprising an outer annular surface configured to engage the ground track, an inner annular surface opposite to the outer annular surface and facing an axis of rotation of the mid-roller wheel, a plurality of spokes disposed radially inwardly of the inner annular surface and configured to resiliently deform under loading on the mid-roller wheel such that respective ones of the spokes between the axis of rotation of the mid-roller wheel and an area of contact of the non-pneumatic tire with the track are in compression and respective ones of the spokes between the axis of rotation of the mid-roller wheel and a peripheral part of the mid-roller wheel not in contact with the track are in tension, a first lateral surface, and a second lateral surface opposite to the first lateral surface, the non-pneumatic tire comprising an elastomeric material extending from the outer annular surface to the inner annular surface and from the first lateral surface to the second lateral surface, the elastomeric material defining a plurality of openings distributed around the non-pneumatic tire and spaced from one another in a circumferential direction of the non-pneumatic tire, wherein each of the openings extends from the first lateral surface to the second lateral surface, and comprising a plurality of interconnecting members, each interconnecting member extending between consecutive ones of the openings and extending continuously in the circumferential direction between the consecutive ones of the openings, the hub comprising a material different from the elastomeric material, the non-pneumatic tire being molded about the hub.