Elastomeric bearing assembly and associated pin structure

Abstract
An elastomeric bearing assembly including a concentric outer member operable for securely engaging a bore structure associated with a first structural member, wherein the concentric outer member is disposed substantially within the bore structure. The elastomeric bearing assembly also including a concentric inner member operable for securely engaging a pin structure associated with a second structural member, wherein the concentric inner member is disposed substantially within the concentric outer member. The elastomeric bearing assembly further including an elastomeric section disposed between the concentric inner member and the concentric outer member, wherein the elastomeric section is bonded to a surface of the inner member and a surface of the outer member, and wherein the elastomeric section is operable for accommodating axial, cocking, and torsion motions of the second structural member relative to the first structural member.
Description


FIELD OF THE INVENTION

[0001] The present invention relates generally to an elastomeric bearing assembly and an associated pin structure. More specifically, the present invention relates to an elastomeric bearing assembly for use in conjunction with the equalizer link of a tractor or other earth-moving vehicle and an associated pin structure operable for securing the elastomeric bearing assembly and the equalizer link to the roller frame assembly of the tractor or other earth-moving vehicle.



BACKGROUND OF THE INVENTION

[0002] A typical tractor or other earth-moving vehicle, also referred to herein as a “dozer,” includes an equalizer link operable for securing the cab assembly of the dozer to the moving tracks or wheels of the dozer, allowing for uniform track-to-ground or wheel-to-ground contact. This equalizer link consists of a hot-rolled steel member or forging. A cylindrical center bearing is provided to secure the equalizer link to the cab assembly of the dozer and two spherical bearings are provided at each end of the equalizer link to the secure the equalizer link to a roller frame assembly associated with the moving tracks or wheels of the dozer, accommodating axial, cocking, and torsion motions. Typically, these spherical end bearings are manufactured from hardened steel and constitute a major wear item. Although the spherical end bearings are sealed and lubricated, the spherical end bearings typically last from about 1,000 hours to about 3,000 hours and, due to inadequate lubrication, fail. Such failure occurs because of the proximity of the spherical end bearings to the tracks or wheels of the dozer and the resulting exposure to dirt, mud, and debris. Failure of the spherical end bearings limits articulation and may destroy the end joints of the equalizer link. Typically, this necessitates expensive re-manufacturing of the retaining-ring groove, seal, and/or bore of the end joints of the equalizer link. For example, a major reworking of the equalizer link may cost as much as about $2,700 and may lead to dozer downtime of about 1 week. Even in a non-failure case, the spherical end bearings must be regularly lubricated and maintained.


[0003] Thus, what is needed is an elastomeric bearing assembly for use in conjunction with the equalizer link of a tractor or other earth-moving vehicle and an associated pin structure operable for securing the elastomeric bearing assembly and the equalizer link to the roller frame assembly of the tractor or other earth-moving vehicle. Preferably, this elastomeric bearing assembly may be used in conjunction with the cylindrical center bearing or the spherical end bearings of the equalizer link, providing a cost-effective, low-maintenance option for reducing and/or preventing equalizer link failure.



BRIEF SUMMARY OF THE INVENTION

[0004] The present invention provides an elastomeric bearing assembly for use in conjunction with the equalizer link of a tractor or other earth-moving vehicle and an associated pin structure operable for securing the elastomeric bearing assembly and the equalizer link to the roller frame assembly of the tractor or other earth-moving vehicle. This elastomeric bearing assembly may be used in conjunction with the cylindrical center bearing or the spherical end bearings of the equalizer link, providing a cost-effective, low-maintenance option for reducing and/or preventing equalizer link failure. Advantageously, the elastomeric bearing assembly of the present invention does not require complex machining and allows +/−3.0 degrees cocking and +/−3.5 degrees torsion with acceptable strains. A radial load of about 25.0 K produces moderate compression stresses that are well within specified requirements. These compression stresses may be further reduced with a large package width. Because the elastomeric bearing assembly of the present invention incorporates rubber, it does not require lubrication and it prevents relative motion or sliding between metal surfaces.


[0005] In one embodiment of the present invention, an elastomeric bearing assembly includes a concentric outer member operable for securely engaging a bore structure associated with a first structural member, wherein the concentric outer member is disposed substantially within the bore structure. The elastomeric bearing assembly also includes a concentric inner member operable for securely engaging a pin structure associated with a second structural member, wherein the concentric inner member is disposed substantially within the concentric outer member. The elastomeric bearing assembly further includes an elastomeric section disposed between the concentric inner member and the concentric outer member, wherein the elastomeric section is bonded to a surface of the inner member and a surface of the outer member, and wherein the elastomeric section is operable for accommodating axial, cocking, and torsion motions of the second structural member relative to the first structural member.


[0006] In another embodiment of the present invention, an elastomeric bearing assembly for use in conjunction with the equalizer link of a tractor or other earth-moving vehicle includes a concentric outer member operable for securely engaging a bore structure associated with a first structural member, wherein the concentric outer member is disposed substantially within the bore structure. The elastomeric bearing assembly also includes a concentric inner member operable for securely engaging a pin structure associated with a second structural member, wherein the concentric inner member is disposed substantially within the concentric outer member. The elastomeric bearing assembly further includes an elastomeric section disposed between the concentric inner member and the concentric outer member, wherein the elastomeric section is bonded to a surface of the inner member and a surface of the outer member, and wherein the elastomeric section is operable for accommodating axial, cocking, and torsion motions of the second structural member relative to the first structural member.


[0007] In a further embodiment of the present invention, an elastomeric bearing assembly includes a concentric outer member and a concentric inner member, wherein the concentric inner member is disposed substantially within the concentric outer member. The elastomeric bearing assembly also includes an elastomeric section disposed between the concentric inner member and the concentric outer member, wherein the elastomeric section is bonded to a surface of the inner member and a surface of the outer member, and wherein the elastomeric section is operable for accommodating axial, cocking, and torsion motions of the concentric inner member relative to the concentric outer member.


[0008] In a still further embodiment of the present invention, a method for installing an elastomeric bearing assembly includes providing: a concentric outer member operable for securely engaging a bore structure associated with a first structural member; a concentric inner member operable for securely engaging a pin structure associated with a second structural member, wherein the concentric inner member is disposed substantially within the concentric outer member; and an elastomeric section disposed between the concentric inner member and the concentric outer member, wherein the elastomeric section is bonded to a surface of the inner member and a surface of the outer member, and wherein the elastomeric section is operable for accommodating axial, cocking, and torsion motions of the second structural member relative to the first structural member. The method for installing the elastomeric bearing assembly also includes pressing the concentric outer member, the concentric inner member, and the elastomeric section into the bore structure using a ram apparatus, thereby precompressing the elastomeric section.







BRIEF DESCRIPTION OF THE DRAWINGS

[0009]
FIG. 1 is a side view of a typical equalizer link operable for securing the cab assembly of a tractor or other earth-moving vehicle to the moving tracks or wheels of the tractor or other earth-moving vehicle, allowing for uniform track-to-ground or wheel-to-ground contact;


[0010]
FIG. 2 is a photograph of an equalizer link, such as that illustrated in FIG. 1, installed in a tractor or other earth-moving vehicle;


[0011]
FIG. 3 is a cross-sectional side view of the mechanism by which a cylindrical center bearing of the equalizer link of FIG. 1 is secured to a saddle structure associated with the cab assembly of a tractor or other earth-moving vehicle;


[0012]
FIG. 4 is a cross-sectional side view of the mechanism by which spherical end bearings of the equalizer link of FIG. 1 are secured to a roller frame assembly associated with the tracks or wheels of a tractor or other earth-moving vehicle;


[0013]
FIG. 5 is a cross-sectional side view of one embodiment of the elastomeric bearing assembly of the present invention;


[0014]
FIG. 6 is a cross-sectional side view of another embodiment of the elastomeric bearing assembly of the present invention;


[0015]
FIG. 7 is a cross-sectional side view of one embodiment of a pin structure associated with the elastomeric bearing assembly of the present invention; and


[0016]
FIG. 8 is a perspective view of the components of the pin structure of FIG. 7.







DETAILED DESCRIPTION OF THE INVENTION

[0017] As described above, the present invention provides an elastomeric bearing assembly for use in conjunction with the equalizer link of a tractor or other earth-moving vehicle and an associated pin structure operable for securing the elastomeric bearing assembly and the equalizer link to the roller frame assembly of the tractor or other earth-moving vehicle. Likewise, the pin structure may be used to secure the elastomeric bearing assembly and the equalizer link to a saddle structure associated with the cab assembly of the tractor or other earth-moving vehicle. Accordingly, this elastomeric bearing assembly may be used in conjunction with the cylindrical center bearing or the spherical end bearings of the equalizer link, providing a cost-effective, low-maintenance option for reducing and/or preventing equalizer link failure. An equalizer link is illustrated in FIG. 1.


[0018] Referring to FIG. 1, the equalizer link 10 consists of a structural member 12, such as a hot-rolled steel member, a forging, or the like. The center portion 14 of the structural member 12 includes a cylindrical center bearing 16. A first end portion 18 of the structural member 12 includes a first spherical end bearing 20 and a second end portion 22 of the structural member 12 includes a second spherical end bearing 24. The equalizer link is operable for securing the cab assembly of a tractor or other earth-moving vehicle to the moving tracks or wheels of the tractor or other earth-moving vehicle, allowing for uniform track-to-ground or wheel-to-ground contact. An installed equalizer link 10 is illustrated in FIG. 2.


[0019] Referring to FIG. 2, the cylindrical center bearing 16 (FIG. 1) of the equalizer link 10 is rotatably attached to a saddle structure (not shown) associated with the cab assembly (not shown) of the dozer. Likewise, the first spherical end bearing 20 (FIG. 1) disposed within the first end portion 18 of the structural member 12 and the second spherical end bearing 24 (FIG. 1) disposed within the second end portion 22 of the structural member 12 are each attached via a pin structure 30 to a roller frame assembly 32 associated with the moving tracks or wheels (not shown) of the dozer. FIGS. 3 and 4 illustrate the specific mechanisms by which the cylindrical center bearing 16 is secured to the saddle structure (see FIG. 3) and the spherical end bearings 20,24 are secured to the roller frame assembly 32 (see FIG. 4).


[0020] Referring to FIG. 3, a bearing assembly 40, such as the elastomeric bearing assembly of the present invention, is disposed within a substantially circular bore 42 running through the center portion 14 of the structural member 12 comprising the equalizer link 10. A pin structure 30, such as the pin structure of the present invention, is inserted through the substantially circular bore 42 running through the center portion 14 of the structural member 12. The pin structure 30 is also inserted through a first substantially circular opening 44 and a second substantially circular opening 46 running through the saddle structure associated with the cab assembly (not shown) of the dozer, thus securing the equalizer link 10 to the cab assembly.


[0021] Referring to FIG. 4, another bearing assembly 40, such as the elastomeric bearing assembly of the present invention, is disposed within a substantially circular bore 52 running through each of the end portions 18,22 of the structural member 12 comprising the equalizer link 10. A pin structure 30, such as the pin structure of the present invention, is inserted through the substantially circular bore 52 running through each of the end portions 18,22 of the structural member 12. The pin structure 30 is also inserted through a first substantially circular opening 54 and a second substantially circular opening 56 running through the roller frame assembly 32 associated with the moving tracks or wheels (not shown) of the dozer, thus securing the equalizer link 10 to the tracks or wheels.


[0022] Referring to FIG. 5, in one embodiment of the present invention, the elastomeric bearing assembly 40 includes an inner member 60 and an outer member 62. The inner member 60 and the outer member 62 may be made of a metal, a metal alloy, a composite, or any other suitable material. The inner member 60 is positioned adjacent to and concentrically about the surface of the pin structure 30 (FIGS. 2, 3, and 4), described above and described in further detail herein below. Preferably, the inner member 60 securely engages the pin structure 30. Likewise, the outer member 62 is positioned adjacent to and concentrically within the substantially circular bore 42,52 (FIGS. 3 and 4) running through the center portion 14 (FIG. 3) and/or the end portions 18,22 (FIG. 4) of the structural member 12 (FIGS. 1, 2, 3, and 4). Preferably, the outer member 62 securely engages the substantially circular bore 42,52. An elastomeric section 64, made of rubber or the like, is disposed between and bonded to the surfaces of the inner member 60 and the outer member 62. It should be noted that, in the present embodiment, the inner member 60 and the outer member 62 have corresponding substantially concave and convex shapes, respectively, operable for accommodating axial, cocking, and torsion motions. Additionally, in the present embodiment, the elastomeric section 64 has a substantially elliptical or barrel shape.


[0023] Referring to FIG. 6, in another embodiment of the present invention, the elastomeric bearing assembly 40 includes an inner member 60 and an outer member 62. The inner member 60 and the outer member 62 may be made of a metal, a metal alloy, a composite, or any other suitable material. The inner member 60 is positioned adjacent to and concentrically about the surface of the pin structure 30 (FIGS. 2, 3, and 4), described above and described in further detail herein below. Preferably, the inner member 60 securely engages the pin structure 30. Likewise, the outer member 62 is positioned adjacent to and concentrically within the substantially circular bore 42,52 (FIGS. 3 and 4) running through the center portion 14 (FIG. 3) and/or the end portions 18,22 (FIG. 4) of the structural member 12 (FIGS. 1, 2, 3, and 4). Preferably, the outer member 62 securely engages the substantially circular bore 42,52. An elastomeric section 64, made of rubber or the like, is disposed between and bonded to the surfaces of the inner member 60 and the outer member 62. It should be noted that, in the present embodiment, the inner member 60 and the outer member 62 have corresponding substantially concave and convex shapes, respectively, operable for accommodating axial, cocking, and torsion motions. Additionally, in the present embodiment, the elastomeric section 64 has a substantially elliptical or barrel shape. A plurality of concentric shim members 70 are also disposed within the elastomeric section 64. FIG. 6 shows two concentric shim members 70, however, as is readily apparent to those of ordinary skill in the art, a greater or lesser number of concentric shim members 70 may be utilized. The concentric shim members 70 provide strength, rigidity, and stability to the elastomeric section 64. The concentric shim members 70 may be made of a metal, a metal alloy, a composite, or any other suitable material.


[0024] In an alternative embodiment of the present invention, the inner member 60, the outer member 62, and the elastomeric section 64 may each have a substantially cylindrical shape, as opposed to the substantially concave and convex shapes illustrated in FIGS. 5 and 6. Additionally, the ends of the outer member 62 may be crimped, so as to securely engage the substantially circular bore 42,52 running through the center portion 14 and/or the end portions 18,22 of the structural member 12, enhancing the axial retention of the elastomeric bearing assembly 40.


[0025] Installation-wise, the elastomeric bearing assembly 40 of the present invention may be forced into the substantially circular bore 42,52 running through the center portion 16 and/or the end portions 18,22 of the structural member 12 using a ram or the like. Preferably, the substantially circular bore 42,52 running through the center portion 16 and/or the end portions 18,22 of the structural member 12 has a substantially funnel shape operable for receiving the elastomeric bearing assembly 40. Alternatively, a substantially funnel-shaped piece may be temporarily attached to the substantially circular bore 42,52 running through the center portion 16 and/or the end portions 18,22 of the structural member 12 for receipt of the elastomeric bearing assembly 40. Advantageously, the installation technique described above precompresses the elastomeric bearing assembly 40, enhancing its durability and general operation. Additionally, the unique elastomer contours utilized in conjunction with the elastomeric section 64 of the present invention accommodate elastomer bulge during precompression, reducing exposure to dirt, mud, and debris that may cause premature damage.


[0026] The pin structure 30 (FIGS. 2, 3, and 4) of the present invention is operable for securing the elastomeric bearing assembly 40 of the present invention between two abutments, such as those associated with the saddle structure 48 (FIG. 3) associated with the cab assembly of the dozer or the roller frame assembly 32 (FIGS. 2 and 4) associated with the tracks or wheels of the dozer.


[0027] Referring to FIG. 7, as described above, the pin structure 30 is inserted through the saddle structure 48 (FIG. 3) associated with the cab assembly of the dozer or the roller frame assembly 32 (FIGS. 2 and 4) associated with the tracks or wheels of the dozer and the elastomeric bearing assembly 40 (FIGS. 3, 4, 5, and 6) of the present invention, securing the tracks or wheels to the cab assembly while allowing a plurality of axial, cocking, and torsion motions there between. Specifically, the pin assembly 30 securely engages the inner member 60 of the elastomeric bearing assembly 40. Preferably, the pin structure 30 has a substantially circular cross-sectional shape. The pin structure 30 may have a plurality of radii, including, for example, a first radius 80 and a second radius 82, wherein the first radius 80 is larger than the second radius 82. The pin structure 30 may be made of a metal, a metal alloy, a composite, or any other suitable material. Preferably, a portion of the second radius 82 of the pin structure 30 forming a notch 84 is configured to fixedly engage a slot 86 disposed within a plate structure 88. The plate structure 88 is fixedly attached to the roller frame assembly 32 associated with the tracks or wheels of the dozer. Thus, the pin structure 30 prevents the inner member 60 of the elastomeric bearing assembly 40 from rotating with respect to the roller frame assembly 32. Alternatively, a collar 90 disposed about the second radius 82 of the pin structure 30 may form the 84 operable for engaging the slot 86 disposed within the plate structure 88. The collar may be made of a metal, a metal alloy, a composite material, or any other suitable material. The pin structure 30 and, specifically, the notch 84 and the collar 90 are shown in greater detail in FIG. 8.


[0028] Although the elastomeric bearing assembly of the present invention has been shown and described with reference to preferred embodiments and examples thereof, it will be readily apparent to those of ordinary skill in the art that other embodiments and examples may perform similar functions and/or achieve similar results. All such equivalent embodiments and examples are within the spirit and scope of the present invention and are intended to be covered by the following claims.


Claims
  • 1. An elastomeric bearing assembly, comprising: a concentric outer member operable for securely engaging a bore structure associated with a first structural member, wherein the concentric outer member is disposed substantially within the bore structure; a concentric inner member operable for securely engaging a pin structure associated with a second structural member, wherein the concentric inner member is disposed substantially within the concentric outer member; and an elastomeric section disposed between the concentric inner member and the concentric outer member, wherein the elastomeric section is bonded to a surface of the inner member and a surface of the outer member, and wherein the elastomeric section is operable for accommodating axial, cocking, and torsion motions of the second structural member relative to the first structural member.
  • 2. The elastomeric bearing assembly of claim 1, wherein the concentric outer member comprises a substantially barrel-shaped member.
  • 3. The elastomeric bearing assembly of claim 1, wherein the concentric outer member comprises a substantially cylinder-shaped member.
  • 4. The elastomeric bearing assembly of claim 1, wherein the concentric inner member comprises a substantially barrel-shaped member.
  • 5. The elastomeric bearing assembly of claim 1, wherein the concentric inner member comprises a substantially cylinder-shaped member.
  • 6. The elastomeric bearing assembly of claim 1, further comprising one or more concentric shim members disposed within the elastomeric section, wherein the one or more concetric shim members are operable for providing the elastomeric section with rigidity.
  • 7. The elastomeric bearing assembly of claim 1, further comprising a plate structure having a slot, wherein the plate structure is fixedly attached to the second structural member.
  • 8. The elastomeric bearing assembly of claim 7, wherein an end of the pin structure comprises a notch operable for non-rotatably engaging the slot of the plate structure.
  • 9. The elastomeric bearing assembly of claim 8, wherein the notch is formed by a collar associated with the end of the pin structure.
  • 10. An elastomeric bearing assembly for use in conjunction with the equalizer link of a tractor or other earth-moving vehicle, comprising: a concentric outer member operable for securely engaging a bore structure associated with a first structural member, wherein the concentric outer member is disposed substantially within the bore structure; a concentric inner member operable for securely engaging a pin structure associated with a second structural member, wherein the concentric inner member is disposed substantially within the concentric outer member; and an elastomeric section disposed between the concentric inner member and the concentric outer member, wherein the elastomeric section is bonded to a surface of the inner member and a surface of the outer member, and wherein the elastomeric section is operable for accommodating axial, cocking, and torsion motions of the second structural member relative to the first structural member.
  • 11. The elastomeric bearing assembly of claim 10, wherein the concentric outer member comprises a substantially barrel-shaped member.
  • 12. The elastomeric bearing assembly of claim 10, wherein the concentric outer member comprises a substantially cylinder-shaped member.
  • 13. The elastomeric bearing assembly of claim 10, wherein the concentric inner member comprises a substantially barrel-shaped member.
  • 14. The elastomeric bearing assembly of claim 10, wherein the concentric inner member comprises a substantially cylinder-shaped member.
  • 15. The elastomeric bearing assembly of claim 10, further comprising one or more concentric shim members disposed within the elastomeric section, wherein the one or more concetric shim members are operable for providing the elastomeric section with rigidity.
  • 16. The elastomeric bearing assembly of claim 10, further comprising a plate structure having a slot, wherein the plate structure is fixedly attached to the second structural member.
  • 17. The elastomeric bearing assembly of claim 16, wherein an end of the pin structure comprises a notch operable for non-rotatably engaging the slot of the plate structure.
  • 18. The elastomeric bearing assembly of claim 17, wherein the notch is formed by a collar associated with the end of the pin structure.
  • 19. An elastomeric bearing assembly, comprising: a concentric outer member; a concentric inner member, wherein the concentric inner member is disposed substantially within the concentric outer member; and an elastomeric section disposed between the concentric inner member and the concentric outer member, wherein the elastomeric section is bonded to a surface of the inner member and a surface of the outer member, and wherein the elastomeric section is operable for accommodating axial, cocking, and torsion motions of the concentric inner member relative to the concentric outer member.
  • 20. The elastomeric bearing assembly of claim 19, wherein the concentric outer member comprises a substantially barrel-shaped member.
  • 21. The elastomeric bearing assembly of claim 19, wherein the concentric outer member comprises a substantially cylinder-shaped member.
  • 22. The elastomeric bearing assembly of claim 19, wherein the concentric inner member comprises a substantially barrel-shaped member.
  • 23. The elastomeric bearing assembly of claim 19, wherein the concentric inner member comprises a substantially cylinder-shaped member.
  • 24. The elastomeric bearing assembly of claim 19, further comprising one or more concentric shim members disposed within the elastomeric section, wherein the one or more concetric shim members are operable for providing the elastomeric section with rigidity.
  • 25. A method for installing an elastomeric bearing assembly, comprising: providing: a concentric outer member operable for securely engaging a bore structure associated with a first structural member; a concentric inner member operable for securely engaging a pin structure associated with a second structural member, wherein the concentric inner member is disposed substantially within the concentric outer member; and an elastomeric section disposed between the concentric inner member and the concentric outer member, wherein the elastomeric section is bonded to a surface of the inner member and a surface of the outer member, and wherein the elastomeric section is operable for accommodating axial, cocking, and torsion motions of the second structural member relative to the first structural member; and pressing the concentric outer member, the concentric inner member, and the elastomeric section into the bore structure using a ram apparatus, thereby precompressing the elastomeric section.