Embodiments of the present disclosure generally relate to truck assemblies for rail vehicles, such as rail cars, and, more particularly, to truck assemblies that include one or more releasable bearing adapters, which are configured to mechanically connect a side frame of the truck assembly to a bearing on a wheel-mounted axle.
Rail vehicles travel along railways, which have tracks that include rails. A rail vehicle includes one or more truck assemblies that support one or more car bodies. Each truck assembly includes two side frames, a bolster, and at least two wheelsets. The bolster extends laterally between and is supported on each side frame. Each wheelset includes an axle, two wheels, and two bearings (e.g., roller bearings). The wheels may be press fit on the axle, and the bearings may be secured at the ends of the axle. Each bearing is connected to one of the side frames via an adapter assembly. The adapter assembly includes a bearing adapter that has an arcuate opening contoured to accommodate the bearing. The adapter assembly also includes an adapter pad that nests into an upper cavity of the bearing adapter. The adapter assembly nests into a pedestal jaw opening at the longitudinal end of each side frame. The adapter assembly is disposed between the bearing and the pedestal jaw. More specifically, the adapter pad is positioned between the bearing adapter and the surfaces of the pedestal jaw that define the opening. The bearing adapter is positioned between the adapter pad and the bearing. The adapter pad is at least partially compressed between the bearing adapter and the surfaces of the pedestal jaw, and the frictional forces at the interfaces between the components secure the bearing adapter in place relative to the side frame.
During travel of the railway freight car, the truck experiences various vertical and lateral forces exerted on the truck via the rails, the spring groups, and inertia. It is possible for the side frame to experience vertical forces that lift or raise the side frame, at least temporarily, relative to the wheelsets in contact with the rails. If the adapter assembly is properly installed, the lifting of the side frame relative to the wheelsets is not a concern due to the weight of the freight car. However, if the adapter assembly is not properly installed, the bearing adapter may at least partially separate from the surface of the bearing, causing the bearing adapter and the bearing to become displaced. The displacement may cause uneven and/or excessive wear on the components, which could reduce the operational lifespan of the components.
A need exists for a railway truck that reduces the likelihood of an incorrectly-installed bearing adapter becoming dislodged or displaced relative to the bearing on the axle during travel of the railway freight car.
With those needs in mind, certain embodiments of the present disclosure provide an adapter assembly of a vehicle. The adapter assembly includes a bearing adapter configured to physically contact a bearing on an axle of the vehicle, and an adapter pad nested within an opening of a side frame of the vehicle and secured to at least one thrust lug of the side frame. The adapter pad includes a base section and legs depending from the base section. The legs are compressed between the at least one thrust lug of the side frame and shoulders of the bearing adapter to exert frictional forces on the shoulders of the bearing adapter. A combination of the frictional forces exerted by the adapter pad on the bearing adapter is less than a weight of the bearing adapter, such that as the side frame rises away from the bearing during movement of the vehicle, the adapter pad is configured to rise relative to the bearing adapter.
Certain embodiments of the present disclosure provide a truck assembly of a rail vehicle. The truck assembly includes a side frame that comprises at least one thrust lug, an axle that comprises a bearing, and an adapter assembly that comprises an adapter pad and a bearing adapter. The adapter pad is nested within an opening of the side frame and secured to the at least one thrust lug via an interference fit. The adapter pad includes a base section and legs depending from the base section. The bearing adapter includes multiple shoulders and is configured to physically contact the bearing. The legs of the adapter pad are compressed between the at least one thrust lug of the side frame and the shoulders of the bearing adapter. The legs include ribs that exert frictional forces on the shoulders. A combination of the frictional forces provided by the ribs is less than a weight of the bearing adapter such that, as the side frame rises away from the bearing during movement of the rail vehicle, the adapter pad is configured to rise relative to the bearing adapter.
Certain embodiments of the present disclosure provide a method for forming a truck assembly of a rail vehicle. The method includes installing an adapter pad within an opening of a side frame such that the adapter pad secures to at least one thrust lug of the side frame via an interference fit. The adapter pad includes a base section and legs depending from the base section. The method includes loading a bearing adapter into the opening such that the legs of the adapter pad are compressed by the shoulders of the bearing adapter. The method also includes coupling the side frame to an axle such that an arcuate lower edge of the bearing adapter physically contacts a bearing on the axle. The legs exert frictional forces on the shoulders of the bearing adapter, and a combination of the frictional forces provided by the legs is less than a weight of the bearing adapter such that the bearing adapter lowers relative to the adapter pad, due to the weight, as the side frame rises away from the bearing during movement of the rail vehicle.
The foregoing summary, as well as the following detailed description of certain embodiments, will be better understood when read in conjunction with the appended drawings. As used herein, an element or step recited in the singular and preceded by the word “a” or “an” should be understood as not necessarily excluding the plural of the elements or steps. Further, references to “one embodiment” are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments “comprising” or “having” an element or a plurality of elements having a particular condition may include additional elements not having that condition.
Certain embodiments of the present disclosure provide an adapter assembly that is held between a bearing on an axle and a side frame of a truck assembly. The adapter assembly includes a metal bearing adapter that engages (e.g., in physical contact) the surface of the bearing. The adapter assembly also includes an elastomeric adapter pad that is held between the metal bearing adapter and a pedestal jaw of the side frame. The adapter pad is retained within a pedestal jaw opening via an interference (or friction) fit. The adapter pad couples to the bearing adapter via an interference fit as well. The present application describes technology that could alleviate concerns of adapter assembly displacement when the side frame rises relative to the bearing, even if installation of the adapter assembly by the end user is not done correctly.
In one or more embodiments, the adapter assembly is designed to enable the metal bearing adapter to release from the adapter pad under its own weight in the event that the side frame lifts or rises relative to the bearing and the axle. For example, when the side frame lifts away from the bearing, the adapter pad at least partially uncouples from the metal bearing adapter. The adapter pad retains its position within the pedestal jaw opening of the side frame and moves with the side frame. The metal bearing adapter drops relative to the adapter pad and retains its mechanical connection to the bearing. Once the side frame lowers again, due to gravity, the adapter pad and the bearing adapter move towards each other and reestablish the interference fit that was present prior to the side frame lifting event. For example, the adapter assembly reestablishes the correct positioning of the adapter pad and the bearing adapter relative to each other and relative to the components that engage the adapter pad and the bearing adapter.
The adapter pad is specifically formulated such that the total amount of frictional force applied on the bearing adapter is less than the weight of the bearing adapter. The bearing assists with supporting the weight of the bearing adapter in a rest position. The rest position represents the state at which weight of the side frame is supported by the bearing on the axle. The truck may be in the rest position for the vast majority of time, only deviating from the rest position when the side frame temporarily lifts away from the bearing during movement of the vehicle. Once the side frame experiences lift such that the normal force provided by the bearing on the metal bearing adapter is reduced or totally removed, the weight of the bearing adapter overcomes the frictional retention provided by the adapter pad. As a result, the metal bearing adapter slides downward relative to the adapter pad. By releasing from the coupled position with the adapter pad, the metal bearing adapter can retain the desired fit and position on the bearing. The bearing adapter avoids becoming dislodged or displaced relative to the bearing, which could cause accelerated wear and other issues. By staying in place on the bearing, there is little or no risk of the side frame and the bearing adapter being displaced in the event of an applied lateral force. Stated differently, the adapter pad is configured to grip the bearing adapter and hold the bearing adapter in place longitudinally and laterally, but the frictional grip force is insufficient to support the weight of the bearing adapter. When the side frame lifts, the weight of the bearing adaptor enables the bearing adapter to lower vertically relative to the adapter pad and the side frame to maintain physical contact with the bearing.
The adapter pad can be formulated to provide a specific amount of frictional force by selecting specific materials with desirable materials properties (e.g., hardness, stiffness, friction coefficient, compressibility, etc.) and specifying the size and thickness of the adapter pad features. The properties of the adapter pad are selected based on the weight of the bearing adapter. For example, the adapter pad may be designed to provide less frictional force against a lighter bearing adapter and to provide more frictional force against a heavier bearing adapter. Optionally, the weight of the bearing adapter may be selected based on existing properties of the adapter pad, such as the amount of frictional force supplied by the adapter pad. The bearing adapter may be composed of one or more metals. The specific type(s) of metal used in the bearing adapter may be selected based on a desired weight of the bearing adapter to accomplish the drop function described herein.
The bolster 12 extends laterally between the two side frames 14 and connects to both side frames 14. The bolster 12 and the side frames 14 may be unitary cast steel structures. Side frames 14 extend longitudinally and parallel with the railway tracks. As used herein, references to “longitudinal” refer to directions that are generally parallel to the rails and the direction of travel of the railway vehicle, and references to “lateral” refer to directions that are generally orthogonal to the rails and the direction of travel of the railway vehicle. Each side frame 14 includes a bolster opening 18 through which one end 16 of the bolster 12 extends. The end 16 of the bolster 12 is supported on a spring group 20, with damping devices known as friction shoes.
The longitudinal end of each side frame 14 includes a downwardly extending pedestal jaw 22. The pedestal jaw 22 includes a pedestal jaw opening 23 that is defined by an inner wall 24 of the pedestal jaw 22, a ceiling section 28 of the pedestal jaw 22, and an outer wall 26 of the pedestal jaw 22 that faces towards the inner wall 24. At the interface between the inner wall 24 and the ceiling section 28, there is an inner thrust lug 29. Inner thrust lug 29 has an angled section that extends from an upper section of the inner wall 24 to an inward section of ceiling section 28. Similarly, but not entirely seen in this perspective view of
The bearing adapter 30 has a generally rectangular structure with four depending shoulders 43, 44, 45, 46 extending therefrom. Three of the shoulders 44, 45, 46 are visible in
The bearing adapter 30 in an embodiment has a rectangular top section 36, which is seen to be generally flat (e.g., planar). Two raised edge supports 38 upwardly extend from one lateral edge of the bearing adapter 30, and two raised edge supports 40 upwardly extend from the opposite lateral edge of the bearing adapter 30. The raised edge supports 38, 40 form a pocket or cavity for receiving the adapter pad 32, enabling the adapter pad 32 to nest along the upper or top side of the adapter 30. The lower or bottom side of the bearing adapter 30 has an arcuate recess along each lower lateral edge, which together define an arcuate opening 42 for receiving and accommodating the convex surface of the bearing. For example, the arcuate opening 42 is adapted to seat against the bearing, as shown in
The depending shoulders are spaced apart from one another. For example, two shoulders 44, 46 are disposed at one longitudinal end of the adapter 30 and are laterally spaced apart from each other. The shoulders 44, 46 define a gap 47 therebetween. The gap 47 is sized and shaped to receive legs of the adapter pad 32, as described herein. The third shoulder 45 and the fourth shoulder, which is not visible, are located at the opposite longitudinal end from the shoulders 44, 46. The third and fourth shoulders are spaced apart from each other similar to the first and second shoulders 44, 46, such that another gap is defined to receive legs of the adapter pad 32.
Referring back to
Additional reference is made to
The adapter pad 32 has a generally rectangular and flat (e.g., planar) base section 50. The adapter pad 32 extends from lateral edge 52 to an opposite lateral edge 53 (shown in
The adapter pad 32 optionally includes depending protrusions 64, 66 that extend downwardly from a bottom surface 72 of the base section 50, as shown in
As shown in
The exterior ribs 80 engage the bearing adapter 30, and more specifically the shoulders 43, 44, 45, 46 of the adapter 30. In the illustrated embodiment, the exterior ribs 80 are disposed along laterally-facing outer surfaces 84 of each of legs 54, 55, 56, 57. The exterior ribs 80 are longitudinally elongated. The interior ribs 82 engage the thrust lugs 29, 31 of the pedestal jaw 22 of the side frame 14. The interior ribs 82 include a longitudinally-elongated interior ribs 82a that are disposed along laterally-facing inner surfaces 85 of each of the legs 54-57. The interior rib 82a of each leg 54-57 may be aligned with the exterior rib 80 in a vertical direction, as shown in
The bearing 60 fits into the arcuate opening 42 of the bearing adapter 30. A rolling or rotating surface 73 of the bearing 60 physically contacts lower edges 74 of the bearing adapter 30 that define the arcuate opening 42. The bearing 60 rotates relative to the adapter 30 while retaining physical contact at the interface between the two components.
With additional reference to
When the adapter assembly 59 is installed in the pedestal jaw opening 23 and the bearing 60 is fit into the arcuate opening 42 of the bearing adapter 30, the legs 54-57 of the adapter pad 32, or at least the ribs 80, 82a thereon, are laterally compressed between the thrust lugs 29, 31 and the shoulders 43-46 of the bearing adapter 30. The two lateral ribs 82b are longitudinally compressed between respective vertical faces of the two thrust lugs 29, 31. For example, each rib 82b is compressed between a vertical face of the thrust lug 29, 31 and an end wall of the bearing adapter 30 (disposed between two shoulders thereof.
Typically the drop distance of the bearing adapter 30 is relatively short, such as no greater than 1 inch or even no greater than 0.5 inch. Although
While various spatial and directional terms, such as top, bottom, lower, mid, lateral, horizontal, vertical, front and the like may be used to describe embodiments of the present disclosure, it is understood that such terms are merely used with respect to the orientations shown in the drawings. The orientations may be inverted, rotated, or otherwise changed, such that an upper portion is a lower portion, and vice versa, horizontal becomes vertical, and the like.
As used herein, a structure, limitation, or element that is “configured to” perform a task or operation is particularly structurally formed, constructed, or adapted in a manner corresponding to the task or operation. For purposes of clarity and the avoidance of doubt, an object that is merely capable of being modified to perform the task or operation is not “configured to” perform the task or operation as used herein.
It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the various embodiments of the disclosure without departing from their scope. While the dimensions and types of materials described herein are intended to define the parameters of the various embodiments of the disclosure, the embodiments are by no means limiting and are exemplary embodiments. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the various embodiments of the disclosure should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means-plus-function format and are not intended to be interpreted based on 35 U.S.C. § 112(f), unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.
This written description uses examples to disclose the various embodiments of the disclosure, including the best mode, and also to enable any person skilled in the art to practice the various embodiments of the disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the various embodiments of the disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if the examples have structural elements that do not differ from the literal language of the claims, or if the examples include equivalent structural elements with insubstantial differences from the literal language of the claims.
This application relates to and claims priority benefits from U.S. Provisional Patent Application No. 63/162,396, filed Mar. 17, 2021, which is hereby incorporated by reference in its entirety.
Number | Date | Country | |
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63162396 | Mar 2021 | US |