ROLLER FRAME ASSEMBLY AND METHOD FOR GROUND ENGAGING TRACK SYSTEM HAVING BU

Abstract

The ground engaging track system (14) includes a track roller frame (16), an idler (28), and flex-resistant rollers (52, 54) supported by the track roller frame (16) at a location between the track roller (50) and the idler (28). The flex-resistant rollers (52, 54) define an idler space (56) that partially receives the idler (28) therein and is positioned to resist flexing of a deflection-sensitive section (118) of the ground engaging track (38).

Description

[Technical field]

[0001] The present disclosure relates generally to ground engaging track systems, and more particularly to a bow resistant roller in a ground engaging track system positioned to counter bending of a deflection sensitive track section. [Background technology]

[0002] Ground engaging track systems on off-highway equipment are used throughout the world in applications ranging from construction, road building, and forestry to mining, landfills, and many others. In a typical example, an endless loop of track links is arranged in parallel track chains that are attached to track shoes and extend around multiple rotating elements, including one or more idlers, track rollers, carrier rollers, and drive sprockets.

[0003] Machines using such track systems are routinely subjected to very severe operating conditions, including travelling over hard and / or uneven bedrock, or soft, yielding bedrock materials, including stumps, rocks, debris, or other materials. Ground engaging track systems are also used for machine propulsion on steep grades, hauling machinery and materials weighing several tons. Track system components are typically designed to be very robust and are often capable of withstanding the harsh conditions. Harsh field conditions may also cause irregular or unpredictable wear of various components, necessitating regular maintenance and / or replacement if performance is to be maintained. Engineers routinely seek improvements and alternative strategies to optimize and / or manage wear and life, and also address newly observed or characterized phenomena related to the maintenance and performance of track systems. One example of a ground engaging track system is described in U.S. Patent No. 6,364,438 to Hasselbusch et al. Summary of the Invention

[0004] In one aspect, the ground engaging track system includes a track roller frame having a front frame end and a back frame end, and an idler recoil assembly attached to the track roller frame. An idler is supported by the idler recoil assembly at the front frame end and includes an idler tread extending circumferentially about an idler axis. The idler is movable in a forward and rearward direction between a rear stop position and a forward position. The ground engaging track system further includes an inner flex resistant roller supported by the track roller frame, and an outer flex resistant roller supported by the track roller frame. An idler space is defined between the inner flex resistant roller and the outer flex resistant roller. The idler tread is within the idler space at the rear stop position of the idler.

[0005] In another aspect, a track roller frame assembly includes a track roller frame having a front frame end, a back frame end, an upper frame side, and a lower frame side. An idler is supported for rotation at the front frame end. The track roller frame assembly further includes an inner flex resistant roller supported by the track roller frame for rotation about a first roller axis and having a first half-axis cantilever supporting a first roller shell having a first roller tread and a first roller shell inner side. The track roller frame assembly further includes an outer flex resistant roller supported by the track roller frame for rotation about a second roller axis and including a second half-axis cantilever supporting a second roller shell having a second roller tread and a second roller shell inner side. The first roller shell inner side and the second roller shell inner side define an idler space extending in a medial-lateral direction between the inner flex resistant roller and the outer flex resistant roller, and the idler is partially positioned within the idler space.

[0006] In yet another aspect, a method of operating a ground engaging track system includes advancing a ground engaging track of a coupled together track link attached to a track shoe around an idler coupled to a track roller frame and a track roller. The method further includes rotating the idler about an idler axis and rotating the track roller about a track roller axis based on the advancement of the ground engaging track. The method further includes urging a deflection sensitive section of the ground engaging track extending between the idler and a leading one of the track roller upwardly based on contact between the deflection sensitive section and an unevenness in at least one of a contour or composition of the underlying bedrock. The method further includes opposing the bending of the deflection sensitive section with a flexion resistant roller supported by the track roller frame in contact with the ground engaging track at a longitudinal location between the idler axis and the track roller axis, the leading one of the track roller.

[0007] In yet another aspect, a roller for a ground engaging track system in a machine includes a roller shell having an outer roller tread extending circumferentially about the roller axis and axially between a first roller shell axial end having a roller shell inner surface and a second roller shell axial end having a roller shell outer surface. The roller shell further includes an inner shell surface extending circumferentially about the roller axis and forming a journal bore, and a thrust bore extending axially between the journal bore and the roller shell inner surface. The roller also includes a roller shaft having a shell support end within the journal bore and a mounting end projecting outwardly of the second roller shell axial end. A face seal assembly is at least partially positioned within the roller shell at the second roller shell axial end. A thrust flange is attached to the mounting end and positioned within the thrust bore, and a shell cap is attached to the roller shell and positioned at least partially within the thrust bore. A thrust bearing is confined within the roller and contacts the thrust flange. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a side view of a machine having a ground engaging track system, according to one embodiment. [Diagram 2] FIG. 2 is a perspective, partial cross-sectional view of a ground engaging track system, according to one embodiment. [Diagram 3] FIG. 3 is a diagram of a ground engaging track system, according to one embodiment. [Figure 4] FIG. 4 is a cross-sectional view of a flex resistant roller, according to one embodiment. [Diagram 5] FIG. 5 is a diagram of a track roller frame assembly of a ground engaging track system, according to one embodiment. [Figure 6] FIG. 6 is a cross-sectional side view of a roller for a ground engaging track system according to another embodiment. [Figure 7] FIG. 7 is a partial cross-sectional side view of a roller for a ground engaging track system according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Referring to FIG. 1, a machine 10 is shown according to one embodiment. The machine 10 includes a frame 12 and a ground engaging track system 14 coupled to the frame 12. The ground engaging track system 14 (hereinafter "track system 14") includes a track roller frame assembly 15 having a track roller frame 16 having a front frame end 18, a back frame end 20, an upper frame side 21, and a lower frame side 23. An idler recoil assembly 22 is attached to the track roller frame 16 and includes a yoke 24 and an actuator 26 coupled to the yoke 24. An idler 28 is supported by the idler recoil assembly 22 at the front frame end 18 and may be mounted for rotation to the yoke 24 about an idler axis of rotation 32. The idler recoil assembly 22 supports the idler 28 for translational movement in a forward and rearward direction between the front frame end 18 and the back frame end 20 such that the idler 28 can move in response to shocks and the like during operation of the track system 14 in a generally known manner. The actuator 26 may include a gas spring, a coil spring, or any other suitable actuator or combination of actuators. The idler 28 may be movable in a forward-rearward direction, for example, between a rearward stop position where the actuator 26 bottoms out or otherwise stops its translational motion and an approximately forward position as shown in FIG. 1. The idler 28 also includes an idler tread 30 that extends circumferentially about an idler axis of rotation 32. The track system 14 may further include a rearward idler 34, and a drive sprocket 36, with the idler 28, rearward idler 34, and drive sprocket 36 arranged in a so-called "high drive" configuration. In other examples, the rotatable track contacting elements of the track system 14 may have a different arrangement, such as an elliptical track configuration. The track system 14 further includes a ground engaging track 38 including track links 40 that are attached to the track shoes 58 and form an endless loop that extends around the various rotatable track contacting elements.

[0010] 2, the ground engaging track 38 may include an inner track chain 42 of joined track links 40 forming an inner track rail 46 and an outer track chain 44 of joined track links 40 forming an outer track rail 48. Track shoes 50 may be attached to both the inner track chain 42 and the outer track chain 44, respectively. Although the machine 10 is shown in the context of a track-type tractor, in other embodiments, the machine 10 may be a track-type loader, half-track, or even another type of off-highway machine. A plurality of track rollers 50 may be coupled to the track roller frame 16 at the lower frame 23 and support a majority of the weight of the machine 10 in a generally conventional manner. The ground engaging track 38 includes a deflection sensing section 118 extending between the idler 28 and one of the leading ones of the track rollers 50, as shown in FIG. 1. Based at least in part on accommodating the forward and rearward movement of the idler 28 supported by the idler recoil assembly 22, the deflection sensing section 118 may be biased upward during use against "flexion" in a manner that does not adversely affect ride, grading performance, and potentially other parameters without the accommodations discussed further herein. It will be appreciated that the deflection sensing section 118 is currently defined based on what portion of the ground engaging track 38 extends between the idler 28 and the leading or forward one of the track rollers 50, and it will be understood that different portions of the ground engaging track 38 are deflection sensing sections because the ground engaging track 38 progresses around various rotatable track contacting elements.

[0011] To reduce or eliminate undesirable flexing or so-called "flexing" of the ground engaging track 38, the track system 14 includes an inner flex resistant roller 52 supported by the track roller frame 16, and an outer flex resistant roller 54 supported by the track roller frame 16. Referring also to FIG. 3, an idler space 56 is defined in an inboard-outboard direction between the inner flex resistant roller 52 (hereinafter "roller 52") and the outer flex resistant roller 54 (hereinafter "roller 54"), with the idler 28 being partially positioned within the idler space 56. The idler tread 30 may be within the idler space 56 at a rear stop position of the idler 28 or may be within the idler space 56 at a forward position of the idler 28. In FIG. 1, the idler shaft 32 is shown when it may be located approximately at a forward position of the idler 28, and is designated by reference numeral 32' when it may appear at a rear stop position of the idler 28. The translation distance 39 between the forward and rear stop positions is also shown in FIG. 1.

[0012] In the illustrated embodiment, rollers 52 and 54 are freely rotatable relative to each other about first and second roller axes 60 and 61, respectively. Rollers 52 and 54 may be coaxially arranged such that first and second roller axes 60 and 61 are collinear. Roller 52 may include a first half-shaft 62 for rotation about first roller axis 60 and a first roller shell 66 cantilever supported by first half-shaft 62. Roller 52 may include a first inner roller shell surface 68 that may be located at an innermost axial end of roller 52. Roller 54 may include a second half-shaft 70 for rotation about second roller axis 61 and a second roller shell 72 cantilever including a second inner roller shell surface 73 supported by second half-shaft 70 that may be located at an innermost axial end of roller 54. From the drawings, it can be seen that the first inner roller shell surface 68 and the second inner roller shell surface 73 may each be substantially planar and substantially circular, and the idler space 56 is a volume, which as shown is a continuous and unobstructed cylindrical volume extending between the first inner roller shell surface 68 and the second inner roller shell surface 73.

[0013] The roller 52 may further include a first roller tread 74 extending circumferentially about the first roller axle 60 and a first radially projecting circumferential flange 76 adjacent the first roller tread 74. The roller 54 may include a second roller tread 78 extending circumferentially about the second roller axle 61 and a second radially projecting circumferential flange 80 adjacent the second roller tread 78. In the illustrated embodiment, the first roller tread 74 extends axially between the first inner roller shell surface 68 and the first radially projecting circumferential flange 76, and the second roller tread 78 extends axially between the second inner roller shell surface 73 and the second radially projecting circumferential flange 80. The flanges 76 and 80 may contact the track link 40 to limit lateral displacement of the ground engaging track 38, including the track chains 42 and 44, relative to the two rollers 52 and 54, by contact between the rollers 52 and 54 and the flanges 76 and 80 on the track link 40. In other embodiments, the flanges 76 and 80 may be positioned adjacent the roller shell inner sides 68 and 73. In yet another embodiment, the flanges 76 and 80 may be provided substantially as shown, with the rollers 52 and 54 including additional radially projecting circumferential flanges adjacent the inner sides 68 and 73, respectively.

[0014] In practical implementations, roller 52 and roller 54 may be substantially identical, and one may be used in place of the other. Thus, the following description of roller 52, which also refers to FIG. 4, may be understood by analogy to roller 54. First half shaft 62 may include a first extended shaft head 64, and a first roller shell 66 is supported on first extended shaft head 64. Roller 54 may be similarly or identically configured. Track roller frame assembly 15, and roller 52 in particular, may include a journal bearing 94 radially between extended shaft head 64 and roller shell 66. Roller 52 may also include a thrust bearing 96 axially between extended shaft head 64 and roller shell 66. A second thrust bearing 97 may be positioned opposite first thrust bearing 96 in some embodiments. First half shaft 62 may also include an axially extending oil hole 104 and a radially extending cross hole 106 configured to supply lubricating oil from oil hole 104 to various bearing surfaces.

[0015] As also shown in FIG. 2, the track roller frame assembly 15 may further include a first clamp mount 84 attached to the track roller frame 16 and supporting the first half shaft 62. Also shown in FIG. 2 is a second clamp mount 87 also attached to the track roller frame 16 and supporting the second half shaft 70, not visible in FIG. 2. It will be appreciated that the track roller frame assembly 15, and in particular the roller 52, may also include a first face seal assembly 92 that seals between the first half shaft 62 and the first roller shell 66, and a second face seal assembly may be provided to seal between the second half shaft 70 and the second roller shell 72. The first clamp mount 84 may include a clamp body 86 having a bore 88 formed therein that receives the first half shaft 62, and a plurality of bolts 90, one of which is shown, that clamp the clamp body 86 to the track roller frame 16. The clamp mount 87 may be similarly configured.

[0016] 5, a diagram of further details of the track system 14 and the track roller frame assembly 15 is shown. In the illustrated embodiment, the track rollers 50 may include standard track rollers supported by the track roller frame 16 and distributed longitudinally along the track roller frame 16 aft of the inner flex resistant rollers 52 and the outer flex resistant rollers 54. Standard track rollers as intended herein mean track rollers including a roller shell 57 having an inner tread 53 and an outer tread 55 that simultaneously contact two track chains when assembled for use. Nevertheless, embodiments contemplate where non-standard track rollers are used, such as cantilever supported split track rollers similar or identical to the flex resistant rollers 52 and 54, or some combination of standard and split track rollers. The inter-roller spacing 110 between the standard track rollers 50 may be different, e.g., smaller, than the inter-roller spacing 112 between the leading or front one of the standard track rollers 50 and each of the flex resistant rollers 52 and 54. The inter-roller spacing 110 may be similar to, or potentially equal to, the roller-to-idler spacing 114 between the roller axles 60, 61 and the idler axle 32, although the disclosure is not limited thereby. The inter-roller spacing 110 is defined between the roller axles 51 of the standard track rollers 50 in this embodiment.

[0017] 6, another roller 152 suitable for use as a flexure resistant roller in a ground engaging track system of a machine is shown. The roller 152 may be used in a similar or identical manner as described with respect to other rollers described herein, and the foregoing description should be understood as applying by analogy to the roller 152, unless otherwise indicated or clear from the context. The roller 152 includes a roller shell 166 having an outer roller tread 174 extending circumferentially about a roller axis 160 and extending axially between a first roller shell axial end 161 having a roller shell inner side surface 168 and a second roller shell axial end 169 having a roller shell outer side surface 171. The roller shell 166 further includes an inner shell surface 173 extending circumferentially about the roller axis 160 and defining a journal bore 175 and a thrust bore 177 extending axially between the journal bore 175 and the roller shell inner side surface 168.

[0018] The roller 152 further includes a roller shaft 162 including a shell support end 163 within the journal bore 175 and a mounting end 165 projecting outwardly from the second roller shell axial end 169. A face seal assembly 192 may be positioned at least partially within the roller shell 166 at the second roller shell axial end 169. In the illustrated embodiment, the face seal assembly 192 is partially received within an axially extending recess 187 formed in the roller shell 166. A radially extending circumferential flange 176 is adjacent the outer tread 174, which extends axially between the flange 176 and the roller shell inner side 168. As with the previous embodiment, a second flange or alternative flange location may be used. A radially inwardly tapered concave transition surface 180 extends from the outer tread 174 to the roller shell inner side 168.

[0019] The roller 152 further includes a thrust flange 191 attached to the shell support end 163 of the roller shaft 162. The thrust flange 191 is positioned within the thrust bore 177. Also, in the illustrated embodiment, the thrust bore 177 has a radially larger diameter and the journal bore 175 has a radially smaller diameter. The inner shell surface 173 may include an inner shoulder surface 195 that transitions between the journal bore 175 and the thrust bore 177. A journal bearing 194 may be positioned within the roller 152 radially between the shell support end 163 and the inner shell surface 173. The roller 152 also includes a shell cap 193 attached to the roller shell 166 and positioned at least partially within the thrust bore 177. In the illustrated embodiment, the shell cap 193 may be attached to the roller shell 166 by a threaded connection formed by the inner threads 181 of the roller shell 166 and the outer threads 182 of the shell cap 193. In alternative embodiments, the shell cap 193 may be attached by another suitable mechanism such as an interference fit, bolts, or welding, to name a few. A thrust bearing 197 is trapped within the roller 152 and contacts the thrust flange 191. The thrust bearing 197 may include a first thrust bearing sandwiched between the thrust flange 191 and the inner shoulder surface 195. The roller 152 may include a second thrust bearing trapped between the thrust flange 191 and the shell cap 193. The thrust flange 191 may be a separate piece from the roller shaft 162 or may be attached to the roller shaft 162. The attachment between the roller shaft 162 and the thrust flange 191 may be by a threaded connection formed by the outer threads 185 on the thrust flange 191 and the inner threads 183 on the roller shaft 162.

[0020] In other embodiments, interference fits, bolts, welding, or any other suitable attachment strategy may be used. The lubrication cavity 200 may be partially formed by each of the shell cap 193 and the thrust flange 191. The plug 186 may be positioned within the shell cap 193 to access, fill, etc. the lubrication cavity 200. As mentioned above, the thrust flange 191 may be a separate piece from the roller shaft 162 and may be partially positioned within an axially extending recess 184 formed within the shell support end 163 of the roller shaft 162. In still other embodiments, the threaded connection may be formed by a protrusion on the roller shaft 162 with external threads mated to internal threads on the thrust flange, the thrust flange and the roller shaft may be formed as a single integral piece, or any of a variety of other structures may be used. The thrust flange 191 extends radially outward of the shell support end 163. 6, it can be seen that the containment of thrust bearings 197 and 199 between thrust flange 191 and roller shell 166, and between thrust flange 191 and shell cap 193, respectively, allows thrust loads between roller shell 166 and roller shaft 162 to be reacted inwardly or outwardly. Roller shaft 162 may include an internal bore (not numbered) generally similar to that of other embodiments described herein that supplies lubricating oil or the like from a lubrication cavity 200 to journal bearing 194 and associated bearing surfaces.

[0021] 7, a roller 252 according to another embodiment is shown and is structured for deployment similar to other embodiments discussed herein in a ground engaging track system. The roller 252 includes a roller shell 266 having an outer tread surface 274 extending circumferentially about a roller axle 260 and axially between a first roller shell axial end 261 having a roller shell inner surface 268 and a second roller shell axial end 269 having a roller shell outer surface 271. The roller shell 266 also includes an inner shell surface 273 that defines a journal bore 275 having a journal bearing 294 positioned therein and a thrust hole 277 extending axially between the journal bore 275 and the roller shell inner surface 268. The face seal assembly 292 may be configured similarly to other face seal assemblies discussed herein and provides a fluid seal between the roller shell 266 and the roller shaft 262. A face seal assembly 292 is at least partially within the roller shell 266 at the roller shell axial end 269. A radially extending circumferential flange 276 is formed adjacent the tread 274 and may be one of two flanges or may be located elsewhere on the roller shell 266, consistent with alternatives to the other embodiments shown. A thrust flange 291 is attached to the roller shaft 262 and positioned within the thrust bore 277. A shell cap 293 is attached to the roller shell 266 and positioned at least partially within the thrust bore 277. A first thrust bearing 297 is trapped within the roller 252 and contacts the thrust flange 291.

[0022] As shown, the thrust bearing 297 is sandwiched between the thrust flange 291 and the roller shell 266. The thrust flange 291 may be attached to the roller shaft 262 by any strategy contemplated herein or yet others, or may be integrally formed with the roller shaft 262. The plug 286 is positioned within the shell cap 293 and fluidly seals the lubricant cavity 300. The roller 252 may further include a dowel bore 259, for example, oriented generally perpendicular to the roller axis 260 and extending through the roller shaft 262 to receive a locating or mounting dowel in a clamp mount assembly or track roller frame.

[0023] Roller 252 has similarities to roller 152 and may be used interchangeably therewith, but also has certain differences. Roller 152 includes first and second thrust bearings 197 and 199 on opposite axial faces of thrust flange 191, while roller 252 includes only one thrust bearing operably coupled between roller shell 266 and thrust flange 291, and another thrust bearing 299 operably coupled between face seal assembly 292 and roller shell 266. Roller 252 may also differ from roller 152 with respect to roller shaft configuration. Roller support end 163 of roller shaft 162 is relatively enlarged relative to mounting end 165, whereas roller shaft 262 may be a straight shaft having a generally consistent diameter along its axial length. [Industrial Applicability]

[0024] As mentioned above, the track system configuration, including roller arrangement, may depend on many different factors and may include the need for the idlers to be able to translate in use relative to their respective track roller frames in response to impacts, etc. The need to accommodate idler translational movement may result in relatively unsupported sections of ground engaging track extending behind the idlers, as standard track rollers are not typically located in locations where the idlers are likely to collide with them. During use, interaction with the foundation can sometimes cause the unsupported sections of track to bow upwards or "flex" in a manner that negatively impacts performance, such as during riding or grading operations.

[0025] In accordance with this disclosure, and with continued reference to FIG. 1, the operating track system 14 may include advancing the ground engaging track 38 around the idlers 28, track rollers 50, and various other rotatable track contacting elements. During advancement of the ground engaging track 38, in either the forward or rearward travel direction, the idlers 28 rotate about the idler axis 32 and the track rollers 50 rotate about the track roller axis 51 based on the advancement of the ground engaging track 38. As shown in FIG. 1, the machine 10 is positioned on a base 116. The deflection sensing section 118 extends between the idler axis 32 and the track roller axis 51, which is the leading one of the track rollers 50. The non-uniformity 120 is present in or on the base 116. The base 116 may include any of soil, gravel, landfill waste, or various other base materials. The non-uniformity 120 refers to a non-uniformity in at least one of the contour or composition of the underlying base 116. A contour unevenness may refer to a bump or the like in the composition of an otherwise more or less uniform bed material. Also, an unevenness in the foundation base may be an unevenness in composition such as the presence of rocks in the soil, large boulders among smaller rocks, stumps, or various other obstacles. As the deflection-sensing section 118 moves and contacts the unevenness 120, the section 118 may be biased upwardly based on the contact between the section 118 and the unevenness 120. A generally upward load is indicated in FIG. 1 by arrow 122. As mentioned above, in certain previous designs without flex-resistant rollers, the upward bias of the deflection-sensing track section may result in flexing. In accordance with the present disclosure, the flexing of the section 118 is opposed by one or more flex-resistant rollers 52 and 54, which are supported by the track roller frame 16 and contact the ground engaging track 38. Contact between the ground engaging track 38 and one or more of the bow resistant rollers may occur at a longitudinal location between the idler shaft 32 and the track roller shaft 51 which is the leading one of the track rollers 50 .

[0026] This specification is for illustrative purposes only and should not be construed to narrow the scope of the disclosure in any manner. Accordingly, those skilled in the art will appreciate that various modifications can be made to the embodiments of the present disclosure without departing from the full and fair scope and spirit of the present disclosure. Other aspects, features, and advantages will become apparent upon consideration of the accompanying drawings and the appended claims. As used herein, the articles "a" and "an" are intended to include one or more items and may be used interchangeably with "one or more." When only one item is intended, "one" or similar language is used. Additionally, as used herein, the terms "has," "have," "having," or similar terms are intended to be open-ended terms. Additionally, the phrase "based on" is intended to mean "based at least in part on" unless expressly stated otherwise.

Claims

1. A ground engaging track system (14), comprising: a track roller frame (16) including a front frame end (18) and a back frame end (20); an idler recoil assembly (22) mounted to the track roller frame (16); an idler (28) supported by said idler recoil assembly (22) at said front frame end (18), said idler (28) including an idler tread (30) extending circumferentially about an idler axis (32) and movable in a forward / rearward direction between a rear stop position and a forward position; an inner bow-resistant roller (52, 152, 252) supported by said track roller frame (16); an outer flex-resistant roller (54) supported by the track roller frame (16); an idler space (56) is defined between the inner flex resistant roller (52, 152, 252) and the outer flex resistant roller (54), and the idler tread (30) is within the idler space (56) at the rear stop position of the idler; the inner flex-resistant roller (52, 152, 252) and the outer flex-resistant roller (54) are freely rotatable relative to each other; the inner bow resistant roller (52, 152, 252) includes a first half shaft (62, 162, 262), a first roller shell (66, 166, 266) supported on the first half shaft (62, 162, 262) for rotation about a first roller axis and having a first inner roller shell surface (68, 168, 268), a first roller tread (74, 174, 274), and a first radially projecting circumferential flange (76, 176, 276) adjacent the first roller tread (74, 174, 274); a ground engaging track system (14), wherein the outer bow resistant roller (54) includes a second half shaft (70), a second roller shell (72) supported on the second half shaft (70) for rotation about a second roller axis and having a second inner roller shell surface (73), a second roller tread (78), and a second radially projecting circumferential flange (80) adjacent the second roller tread (78).

2. a plurality of standard track rollers (50) supported by said track roller frame (16) and distributed longitudinally along said track roller frame (16) rearward of said inner flex resistant rollers (52, 152, 252) and said outer flex resistant rollers (54); 2. The ground engaging track system of claim 1, further comprising: a ground engaging track including an inner track chain of track links coupled together forming an inner track rail contacted by the inner flexing resistant roller, an outer track chain of track links coupled together forming an outer track rail contacted by the outer flexing resistant roller, and a plurality of track shoes attached to the inner track chain and the outer track chain, respectively.

3. A track roller frame assembly (15), a track roller frame (16) including a front frame end (18), a back frame end (20), an upper frame side (21), and a lower frame side (23); an idler (28) supported for rotation at said front frame end (18); an inner flex resistant roller (52, 152, 252) including a first half-axis (62, 162, 262) cantilever supported by said track roller frame (16) for rotation about a first roller axis and supporting a first roller shell (66, 166, 266) having a first roller tread (74, 174, 274) and a first roller shell inner side (68, 168, 268); an outer flex resistant roller (54) supported by said track roller frame (16) for rotation about a second roller axis and including a second half-axis (70) cantilever supporting a second roller shell (72) having a second roller tread (78) and a second roller shell inner side (73); the first roller shell inner surface (68, 168, 268) and the second roller shell inner surface (73) define an idler space (56) extending in an inward-outward direction between the inner flex resistant roller (52, 152, 252) and the outer flex resistant roller (54), and the idler (28) is partially positioned within the idler space (56); the idler space (56) being a volume extending continuously between the first roller shell inner surface (68, 168, 268) and the second roller shell inner surface (73); the inner flex resistant roller (52, 152, 252) includes a first radially projecting circumferential flange (76, 176, 276) and the outer flex resistant roller (54) includes a second radially projecting circumferential flange (80); a first roller tread (74, 174, 274) extending axially between the first roller shell inner side (68, 168, 268) and the first radially projecting circumferential flange (76, 176, 276), and a second roller tread (78) extending axially between the second roller shell inner side (73) and the second radially projecting circumferential flange (80).

4. 4. The track roller frame assembly (15) of claim 3, further comprising: a first clamp mount (84) attached to said track roller frame (16) and supporting said first half shaft (62, 162, 262); a first face seal assembly (92, 192, 292) sealing between said first half shaft (62, 162, 262) and said first roller shell (66, 166, 266); a second clamp mount (87) attached to said track roller frame (16) and supporting said second half shaft (70); and a second face seal assembly (92, 192, 292) sealing between said second half shaft (70) and said second roller shell (72).

5. 5. A track roller frame assembly (15) according to claim 3 or 4, wherein each of the first half shaft (62, 162) and the second half shaft (70) includes an enlarged shaft head (64) and further includes a journal bearing (94, 194) radially between the respective enlarged shaft head (64) and the roller shell (66, 72, 166), and a thrust bearing (96, 97, 197, 199) axially between the respective enlarged shaft head (64) and the roller shell (66, 72, 166).

6. 1. A method of operating a ground engaging track system, comprising: advancing ground engaging tracks (38) of coupled together track links (40) attached to track shoes (58) around idlers (28) and track rollers (50) coupled to a track roller frame (16); rotating the idler (28) about an idler axis and rotating the track roller (50) about a track roller axis based on the advancement of the ground engaging track (38); biasing a deflection sensitive section (118) of the ground engaging track (38) extending between the idler (28) and one of the leads of the track roller (50) upwardly based on contact between the deflection sensitive section (118) and an unevenness in at least one of a contour or composition of an underlying substrate (116); opposing bending of the deflection sensitive section (118) with a bend resistant roller (52, 54, 152, 252) supported by the track roller frame (16) in contact with the ground engaging track (38) at a longitudinal location between the idler shaft and the track roller shaft of the leading one of the track rollers (50); the opposing side of the bend in the deflection-sensing section (118) is opposed by two bend-resistant rollers (52, 54, 152, 252) cantilevers supported on a track roller frame (16) facing each other such that an idler space (56) receiving the idler (28) extends continuously through the idler space; the method further comprising limiting lateral displacement of the ground engaging track (38) relative to the two flex resistant rollers (52, 54, 152, 252) by contact between radially protruding circumferential flanges (76, 80, 176, 276) on the two flex resistant rollers (52, 54, 152, 252) and track links (40) in the ground engaging track (38).

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