Low profile track suspension system

Abstract

The present disclosure relates to a mainframe isolator for a tracked vehicle, including: a bottom plate configured for mounting on a track frame; an elastomer layer; a top plate; and a safety block connected to the bottom plate. The top plate and the safety block are configured to receive a mainframe leg. The present disclosure also relates to a method of mitigating shock loading on a tracked vehicle, including the steps: providing a mainframe isolator, the mainframe isolator having a bottom plate configured for mounting to a track frame, an elastomer layer, a top plate, and a safety block connected to the bottom plate, the top plate and the safety block being configured to receive a mainframe leg; mounting the mainframe isolator to a track frame of the tracked vehicle; and, mounting a mainframe leg of the tracked vehicle to the mainframe isolator.

Description

LOW PROFILE TRACK SUSPENSION SYSTEMCROSS-REFERENCE TO RELATED CASES

[0001] This application claims the benefit of U.S. provisional patent application Serial No. 63 / 554,700, filed on February 16, 2014, and incorporates such provisional application by reference into this disclosure as if fully set out at this point.FIELD OF THE INVENTION

[0002] The present invention relates to a tracked vehicle suspension, in particular a mechanical isolator for preventing the transfer of vibrations and other forces from a track frame to the chassis of the tracked vehicle.BACKGROUND OF THE INVENTION

[0003] Tracked vehicles typically consist of a chassis or hull supported by two or more continuous tracks. The tracks are made up of a series of interconnected metal or rubber links with embedded treads that provide traction against the ground. One of the primary advantages of tracked vehicles is their superior off-road mobility. The tracks distribute the vehicle's weight more evenly, reducing the risk of sinking into soft or uneven terrain. This allows tracked vehicles to traverse areas where wheeled vehicles might struggle or become immobilized. Tracked vehicles are commonly used in construction and earthmoving projects due to their ability to navigate through rough terrain and carry heavy loads. Bulldozers, excavators, and loaders are examples of tracked vehicles used in construction and mining industries. Military tracked vehicles include tanks, armored personnel carriers, infantry fighting vehicles, and engineering vehicles. Tracked vehicles are also used in agriculture, especially in wet or muddy conditions, as well as in snow and ice environments, such assnowcats.

[0004] Because track systems are complex relative to wheeled vehicles, and because tracked vehicles are typically used in rugged conditions, they often require extensive maintenance. Bumpy terrain, for example, can cause excessive wear to a tracked vehicle’s chassis, suspension, and track frames, resulting in premature equipment failures. A large tracked vehicle driving over a substantial bump or large rock can experience a force in excess of 10 times the force due to gravity. For this reason, many tracked vehicles are constructed with heavier frames than would be required for a tracked vehicle that operated only on smooth terrain.

[0005] On a typical tracked vehicle, the tracks ride along track frames. The vehicle chassis mounts to the track frames by means of a suspension, including four mainframe legs — two on each side — which connect the track frames to the chassis of the vehicle. One place where tracked vehicles experience significant force when transversing rough terrain is in the suspension connecting the track frames to the vehicle chassis, including the mainframe legs.

[0006] What is needed is a device and system for a tracked vehicle suspension that mitigates the forces communicated from a tracked vehicle’s track frames to the remainder of the vehicle and a method of implementing that device.SUMMARY OF THE INVENTION

[0007] The present invention is a mainframe isolator for a tracked vehicle, including: a bottom plate configured for mounting on a track frame; an elastomer layer; a top plate; and a safety block connected to the bottom plate. The top plate and the safety block are configured to receive a mainframe leg.

[0008] The present invention also includes a method of mitigating snocK loading on a tracked vehicle. The method including the steps: providing a mainframe isolator, the mainframe isolator having a bottom plate configured for mounting to a track frame, an elastomer layer, a top plate, and a safety block connected to the bottom plate, the top plate and the safety block being configured to receive a mainframe leg; mounting the mainframe isolator to a track frame of the tracked vehicle; and, mounting a mainframe leg of the tracked vehicle to the mainframe isolator.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 is a perspective view of a mainframe leg on a tracked vehicle chassis.

[0010] Figure 2A is a top view of an embodiment of a mainframe isolator.

[0011] Figure 2B is an end view, with internal detailing, along the longitudinal direction of the mainframe isolator of Figure 2A.

[0012] Figure 2C is a bottom view of the mainframe isolator of Figure 2A.

[0013] Figure 2D is a cross-section view along the transverse direction of the mainframe isolator of Figure 2A.

[0014] Figure 2E is an isometric view of the mainframe isolator of Figure 2A.

[0015] Figure 2F is a detail view of cross section view 2D.

[0016] Figure 3 is a cross-section view along the transverse direction of an embodiment of a mainframe isolator.

[0017] Figure 4A is a top view of an embodiment of a mainframe isolator.

[0018] Figure 4B is an end view, with internal detailing, along the longitudinal direction of the mainframe isolator of Figure 4A.

[0019] Figure 4C is an end view, with internal detailing, along me transverse direction of the mainframe isolator of Figure 4A.

[0020] Figure 4D is an isometric view of the mainframe isolator of Figure 4A.

[0021] Figure 5A is a top view of an embodiment of an assembled mainframe isolator.

[0022] Figure 5B is an end view along the longitudinal direction of the mainframe isolator of Figure 5 A.

[0023] Figure 5C is a cross-section view along the longitudinal direction of the mainframe isolator of Figure 5 A.

[0024] Figure 5D is an end view along the transverse direction of the mainframe isolator of Figure 5 A.

[0025] Figure 6 is an exploded view of the mainframe isolator of Figure 5A.

[0026] Figure 7 is a photograph of a mainframe isolator attached to a track frame and a mainframe leg.

[0027] Figure 8 is a perspective view of an embodiment of a fully assembled mainframe isolator connected to a mainframe leg.

[0028] Figure 9 is a cross-section view along the transverse direction of the mainframe isolator and mainframe leg of Figure 8.

[0029] Figure 10 is a cross-section view along the longitudinal direction of the mainframe isolator and mainframe leg of Figure 8.

[0030] Figure 11 is a photograph of a mainframe isolator installed on a track frame.

[0031] Figure 12 is a photograph of a tracked vehicle witn a mainrrame isolator installed.

[0032] Figure 13 is a photograph of another tracked vehicle with a mainframe isolator installed.DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] Figure 1 depicts a perspective view of a mainframe leg 110 on a tracked vehicle chassis 104. A typical tracked vehicle has track frames (not shown) mounted to its chassis 104 or hull by a plurality of mainframe legs 110. As a tracked vehicle traverses rough terrain, the track frames, mainframe legs 110, and chassis 104 can experience shock loading, which is the sudden application of a heavy load or force to the vehicle and its components. Track frames can w'eigh 10,000 lbs. or more on a large track vehicle. In tests, transversing a small block caused a tracked vehicle to experience shock loading 10 times the force of gravity and, in some cases, as high as 13 times the force of gravity.

[0034] Usually, a tracked vehicle has two mainframe legs 110 per track frame. Each mainframe leg 110 extends from the main frame of the chassis 104 and attaches to a track frame with bolts or other fasteners, creating a rigid connection between the track frames and the rest of the tracked vehicle. For example, the mainframe leg 110 may have a mounting plate 112 with holes 114 and, optionally, spacers 116, for attaching the mainframe leg 110 to a track frame with bolts or other fasteners. The mainframe leg 110 may have a safety -block hole 118 adapted to surround a safety block for restricting the lateral motion of the mainframe leg 110 relative to the track frame when it is installed. The mainframe leg 110 may have a notch 120 that complements a top stop attached to the safety block. Themainframe leg 110 may have a seal backing (not shown) that coordinates wnn me notcn izu to surround the top stop and the safety block.

[0035] The mainframe isolator of the present disclosure mitigates shock loading by impeding vibrations and other forces between the track frame and the mainframe leg. The mainframe isolator of the present disclosure works by introducing an elastomer shock absorber between the mainframe leg and the track frame.

[0036] Figure 2A shows a top view of an embodiment of mainframe isolator 200 of the present disclosure. Figure 2B shows an end view, with internal detailing, along the longitudinal direction of the mainframe isolator of Figure 2A. The mainframe isolator 200 may have a bottom plate 202 for mounting to the track frame; an elastomer layer 204 for shock absorption; and a top plate 206 for mounting to the mainframe leg 110. The bottom plate 202 may connect to a track frame 102 by a plurality of bolts or other fasteners as known in the art. The bottom plate 202 may have holes 208 and, optionally, spacers may be adapted to fit the bolts or other fasteners. The elastomer layer 204 may be attached to the bottom plate 202 with adhesives, heat bonding (vulcanization), a combination of thereof, or other means as known in the art. Likewise, the top plate 206 may be attached to the elastomer layer 204 with adhesives, heat bonding, or a combination thereof. The top plate 206 may have fastener holes 212 configured for attaching to a mounting plate 112 of a mainframe leg 110 with bolts or other fasteners. The fastener holes in the top plate 212 may be threaded to receive fasteners. The top and bottom plates 206, 202 of the mainframe isolator 200 may be steel. The elastomer layer 204 may be a natural rubber or synthetic rubber, such as neoprene. In embodiments, the elastomer layer 204 may be selected to maintain its flexibility and resilience to temperatures in the range of -40° C to 50° C.

[0037] Figure 2C shows another top view of the mainframe isolator oi rigure ZA.Figures 2D and 2F show a cross-section view along the transverse direction of the mainframe isolator of Figure 2A. The mainframe isolator 200 may include stops and failsafe mechanisms to prevent over-compressing or over-stretching the elastomer layer 204, which can cause the elastomer to lose its memory or tear. To prevent excessive compression of the elastomer layer 204, the mainframe isolator 200 may include stops 214 fastened to the top plate 206 and extending from the top plate 206 through the elastomer layer 204 and, optionally, into the bottom plate 202. A gap 216 may be left between each stop 214 and the bottom plate 202 (or, optionally, the track frame). The stops 214 may attach to the top plate 206 using screws, spring pins, or other fasteners. The depth of the gap 216 between each stop and the bottom plate 202 (or track frame) may determine the maximum compression of the elastomer layer 204. In embodiments, the gap 216 may be selected to prevent damage to the elastomer layer 204, for example, 1 / 8 of an inch. The stops 214 may be fabricated from steel or another hard material, but the inventors have found that softer metals, such as aluminum and bronze, also make effective stops. Each stop 214 may be at least partially coated plastic or another soft material to minimize the force with which each stop 214 impacts the bottom plate 202 (or track frame).

[0038] Figure 2E is an isometric view of the mainframe isolator of Figure 2A. To limit or prevent lateral motion of the mainframe leg 110 relative to the track frame, a mainframe isolator 200 may include a safety block 218 attached to the bottom plate 202. Referring also to Figure 1, the safety block 218 may be shaped to conform to a corresponding safety-block hole 118 in a mainframe leg 110. The safety block 218 may extend up through a hole in the elastomer layer 204 and the top plate 206 so that the safety block 218 extends above the top plate 206. The safety block 218 may be fabricated from steel and attached tothe botom plate 202 by welding or other means known in the art. A narrow gap Detween rne safety block 218 and the elastomer layer 204 and top plate 206 may be filled with grease to minimize wear between the elastomer layer 204 and the safety block 218. The grease may be selected to maintain its viscosity' in temperatures ranging from -40°C to 50°C. An internal impact ring 226 may further limit movement of the mainframe leg 110. The internal impact ring 226 may circumscribe the safety block and be adapted to buffer the connection among the top plate 206, the mainframe leg 110, and the safety block 218.

[0039] The mainframe isolator of the present disclosure may be configured to restrict vertical and shear travel of the mainframe leg relative to a track frame to a distance that protects the elastomer layer from losing its memory or otherwise becoming damaged, for example, 1 / 2 inch or 7 / 16 inches.

[0040] Figure 3 shows a cross-section view along the transverse direction of an embodiment of a mainframe isolator 200. In this embodiment, a polymer layer or piece 334 has been applied to the stops 214 of the mainframe isolator 200.

[0041] Figure 4A shows a top view of an embodiment of a mainframe isolator of the present disclosure. Figure 4B shows an end view, with internal detailing, along the longitudinal direction of the mainframe isolator of Figure 4A. Figure 4C depicts an end view, with internal detailing, along the transverse direction of the mainframe isolator of Figure 4A. Figure 4D shows an isometric view of the mainframe isolator of Figure 4A.

[0042] Figure 5A shows a top view of an embodiment of an assembled mainframe isolator 200. Bolts are installed in holes in the botom plate 202 and the top plate 206, as if the mainframe isolator 200 were installed on a tracked vehicle. Like the embodiment ofFigure 2A, the mainframe isolator 200 in Figure 5A has a bottom plate zuz ana top piaie zuo A top seal guard 530 is shown in Figure 5A.

[0043] Figure 5B shows an end view along the longitudinal direction of the mainframe isolator 200. The seal backing 122 of a mainframe leg 110 may cover the safety block. The top seal guard 530 may be attached to the seal backing 122 and the mainframe leg 110 when the mainframe isolator 200 is installed on a tracked vehicle. Figure 5C shows a cross-section view along the longitudinal direction of the mainframe isolator of Figure 5A. An internal impact ring 526, adapted to buffer the connection between the top plate 206, the mainframe leg 110, and the safety block 218, may be inserted into the gap between the safety block 218 and the top plate 206. The impact ring 526 may circumscribe the safety block 218. The impact ring 526 may further limit lateral movement of the mainframe leg. The impact ring 526 may be fabricated from steel or another hard material, but the inventor has found that softer metals, such as aluminum and bronze, also make effective impact rings. The impact ring 526 may be coated in grease to minimize wear. A top stop 528 may be attached to the safety block 218 with bolts or other fasteners. The top seal guard 530 may cover the top stop 528. Figure 5D is an end view along the transverse direction of the mainframe isolator of Figure 5A. Figure 6 shows an exploded view of the mainframe isolator 200 of Figure 4 A.

[0044] Figure 7 shows a mainframe isolator 200 bolted to a track frame 102, with a mainframe leg 110 installed. In Figure 7, the top seal guard 530 of the mainframe isolator 200 is not installed. The bottom plate 202 of the mainframe isolator 200 may be attached to the track frame 102 with bolts or other fasteners. The mainframe isolator 200 may be centered longitudinally on the track frame 102 to prevent instability or twisting while in use. A mainframe leg 110 may attach to the mainframe isolator 200 by bolting the mounting plate112 of the mainframe leg 110 to the top plate 206. Referring also io rigures i ana o, me mainframe leg 110 may have a safety-block hole 118 and a notch 120 to accept the top stop 528. The mainframe leg 110 may have a seal backing 122 that coordinates with the notch 120 to surround the top stop 528, safety block 218, and internal impact ring 526. The mainframe leg 110 may be sealed to the top plate to contain grease and keep dirt and other contaminants away from the internal components of the mainframe isolator 200. The top seal guard 530 may be fabricated from steel and sized and shaped to complement the mainframe leg 110. The top seal guard 530 may have a top seal 732 to contain grease and keep dirt and other contaminants from the internal components of the mainframe isolator 200. Grease may be applied around the top stop 528 and between the top seal guard 530 and the mainframe leg 110 before securing the top seal guard 530 to the mainframe leg 110.

[0045] Figure 8 shows an embodiment of a fully assembled mainframe isolator 200 connected to a mainframe leg 110. The top seal guard 530 is installed on the mainframe leg 110

[0046] Figures 9 and 10 show the mainframe isolator of Figure 8.

[0047] Figure 10 shows a mainframe isolator 200 installed on a tracked vehicle 100. Referring also to Figures 1 and 5, a top seal guard 530 may cover the isolator top stop 528 and the mainframe leg 110. The top seal guard 530 may be connected to the mainframe leg 110 using bolts, screws, or other fasteners.

[0048] Figure 11 shows a mainframe isolator installed on a track frame.

[0049] Figures 12 and 13 show tracked vehicles with mainframe isolators installed.

[0050] A tracked vehicle with mainframe isolators as described herein may have significantly less shock loading when traversing rough terrain compared to a similar vehiclewithout isolators. In a bump test, a control vehicle without isolators experienced snocx loading of 10 to 13 times the force of gravity. A similar vehicle with mainframe isolators experienced shock loading of only 3 to 4 times the force of gravity. This decrease in shock loading helps extend the life of the tracked vehicle’s parts and improves operator comfort.

[0051] Use of mainframe isolators as disclosed herein also distributes track loads more evenly across track frames and across the tracked vehicle as a whole. Furthermore, mainframe isolators allow track frames to tilt slightly relative to the vehicle chassis, enabling the tracked vehicle to navigate more varied terrains.

[0052] Because mainframe isolators of the present disclosure mitigate the effects of shock loading, a tracked vehicle with mainframe isolators can be constructed using lighter materials than those designed for use without mainframe isolators.* * * *

[0053] It is to be understood that the terms "including", "comprising", "consisting" and grammatical variants thereof do not preclude the addition of one or more components, features, steps, or integers or groups thereof and that the terms are to be construed as specifying components, features, steps or integers.

[0054] If the specification or claims refer to "an additional" element, that does not preclude there being more than one of the additional element.

[0055] It is to be understood that where the claims or specification refer to "a" or "an" element, such reference is not be constmed that there is only one of that element.

[0056] It is to be understood that where the specification states that a component, feature, structure, or characteristic "may", "might", "can" or "could" be included, that particular component, feature, structure, or characteristic is not required to be included.

[0057] Where applicable, although state diagrams, flow diagrams or ootn may oe used to describe embodiments, the invention is not limited to those diagrams or to the corresponding descriptions. For example, flow need not move through each illustrated box or state, or in exactly the same order as illustrated and described.

[0058] Methods of the present invention may be implemented by performing or completing manually, automatically, or a combination thereof, selected steps or tasks.

[0059] The term "method" may refer to manners, means, techniques and procedures for accomplishing a given task including, but not limited to, those manners, means, techniques and procedures either known to, or readily developed from known manners, means, techniques and procedures by practitioners of the art to which the invention belongs.

[0060] The term “at least” followed by a number is used herein to denote the start of a range beginning with that number (which may be a range having an upper limit or no upper limit, depending on the variable being defined). For example, “at least 1” means 1 or more than 1. The term “at most” followed by a number is used herein to denote the end of a range ending with that number (which may be a range having 1 or 0 as its lower limit, or a range having no lower limit, depending upon the variable being defined). For example, “at most 4” means 4 or less than 4, and “at most 40%” means 40% or less than 40%.

[0061] When, in this document, a range is given as “(a first number) to (a second number)” or “(a first number) - (a second number)”, this means a range whose lower limit is the first number and whose upper limit is the second number. For example, 25 to 100 should be interpreted to mean a range whose lower limit is 25 and whose upper limit is 100. Additionally, it should be noted that where a range is given, every possible subrange or interval within that range is also specifically intended unless the context indicates to the contrary. For example, if the specification indicates a range of 25 to 100 such range is alsointended to include subranges such as 26 -100, 27-100, etc., 25-99, 2 y», etc., as wen as any other possible combination of lower and upper values within the stated range, e.g., 33-47, 60- 97, 41-45, 28-96, etc. Note that integer range values have been used in this paragraph for purposes of illustration only and decimal and fractional values (e.g., 46.7 - 91.3) should also be understood to be intended as possible subrange endpoints unless specifically excluded.

[0062] It should be noted that where reference is made herein to a method comprising two or more defined steps, the defined steps can be carried out in any order or simultaneously (except where context excludes that possibility), and the method can also include one or more other steps which are carried out before any of the defined steps, between two of the defined steps, or after all of the defined steps (except where context excludes that possibility).

[0063] Further, it should be noted that terms of approximation (e.g., “about”, “substantially”, “approximately”, etc.) are to be interpreted according to their ordinary and customary meanings as used in the associated art unless indicated otherwise herein. Absent a specific definition within this disclosure, and absent ordinary and customary usage in the associated art, such terms should be interpreted to be plus or minus 10% of the base value.

[0064] Thus, the present invention is well adapted to carry out the objects and attain the ends and advantages mentioned above as well as those inherent therein. While the inventive device has been described and illustrated herein by reference to certain preferred embodiments in relation to the drawings attached thereto, various changes and further modifications, apart from those shown or suggested herein, may be made therein by those of ordinary skill in the art, without departing from the spirit of the inventive concept the scope of which is to be determined by the following claims.

Claims

CLAIMSWhat is claimed is:

1. A mainframe isolator for a tracked vehicle having a track frame and a mainframe leg, the isolator comprising: a top plate; an elastomer layer positioned between said top plate and the track frame; a safety block in rigid communication with the track frame; wherein the top plate and the safety block are configured to receive the mainframe leg.

2. The mainframe isolator of claim 1 further including a bottom plate configured for mounting on the track frame.

3. The mainframe isolator of claim 2 wherein said safety block is attached to said bottom plate.

4. The mainframe isolator of claim 3 wherein said safety block extends through said elastomer layer.

5. The mainframe isolator of claim 1 wherein said top plate including a stop fastened thereto.

6. The mainframe isolator of claim 5 wherein said stop extends from said top plate through said elastomer layer.

7. The mainframe isolator of claim 6 including a gap between said stop and said bottom plate.

8. The mainframe isolator of claim 6 wherein said stop extends from said top plate through said elastomer layer and into said bottom plate.

9. The mainframe isolator of claim 8 wherein an internal impact ring circumscrmes said safety block;10. The mainframe isolator of claim 8 including a gap between said stop and said bottom plate.

11. The mainframe isolator of claim 10 wherein said gap is filled with grease.

12. The mainframe isolator of claim 1 wherein said top plate includes a plurality of stops fastened thereto.

13. The mainframe isolator of claim 1 wherein said elastomer layer is adapted to be flexible and resilient.

14. The mainframe isolator of claim 13 wherein said elastomer layer is adapted to have an effective temperature range of -40°C to 50°C.

15. A method of mitigating shock loading on a tracked vehicle having a track frame and a mainframe leg, the method comprising the steps of: providing a mainframe isolator, the mainframe isolator having a bottom plate configured for mounting to the track frame, an elastomer layer, a top plate, and a safety block connected to the bottom plate, the top plate and the safety block being configured to receive the mainframe leg; mounting the mainframe isolator to the track frame of the tracked vehicle; and mounting the mainframe leg of the tracked vehicle to the mainframe isolator.

Images