ELASTOMERIC ELEMENT FOR A SIDE BEARING

Field of the Invention

[001 ] The present invention relates to railway bearing arrangements and in particular to a elastomeric element for a railway car side bearing. Background

[002] Referring to figure 1 , there is shown a side bearing 0 for a railway car according to the prior art. The side bearing 0 comprises a metal cap 1 which engages two elastomeric blocks 3. The elastomeric blocks 3 are housed within a bearing cage 5, kept therein by end encloses 4 and surrounding roller 2.

[003] Figure 2 shows a further side bearing 6 for a railway car according to the prior art as disclosed in US 4,859,089. Specifically, there is shown a side bearing 6 for a railway car having a pair of spaced elongated resilient elastomeric elements which bias the element of the side bearing in operative position and which element preferably have uppermost separate members which are effective for generating increased frictional dissipation of energy. The other reference numerals in figure 2 are to be ignored.

[004] Yet further, figure 3 shows an elastomeric block 7 according to the prior art as is substantially disclosed in Patent No. 3,957,318. Figure 3 shows a resiliently deformable elastomeric member 7 having a configuration suitable to accommodate insertion into the side bearing 6 mentioned above. Each elastomeric block 7 includes a relatively "hard" upper portion 54 and a relatively "soft" lower portion 64. The compression modulus of the elastomer of the upper portion 54 of the block 7 has a modulus of elasticity (unit stress per unit' strain) in the range of 7,000 to 20,000 psi or at least at least 15,000 pounds per inch for acceptable hunting control. The other reference numerals in figure 3 to be ignored.

[005] The present invention seeks to provide an elastomeric element for a railway car side bearing, which will overcome or substantially ameliorate at least some of the deficiencies of the prior art, or to at least provide an alternative.

[006] It is to be understood that, if any prior art information is referred to herein, such reference does not constitute an admission that the information forms part of the common general knowledge in the art, in Australia or any other country.

Summary

[007] According to one aspect of the present invention, there is provided an elastomeric element for a railway car side bearing, the elastomeric element comprising a compression portion adapted to compress under load in use, wherein the compression portion comprises one or more ribs adapted for facilitating compression of the compression portion in use.

[008] In one embodiment, the one or more ribs, are two or more ribs.

[009] In one embodiment, the two or more ribs are between 3 and 7 ribs.

[0010] In one embodiment, the two or more ribs are 4 ribs.

[001 1 ] In one embodiment, the elastomeric element is configured to compress elastically in use to between 20% and 99.99% of its uncompressed height.

[0012] In one embodiment, the elastomeric element is configured to compress elastically in use to between 50% and 99.99% of its uncompressed height.

[0013] In one embodiment, the elastomeric element is configured to compress elastically in use to between 70% and 99.9% of its uncompressed height.

[0014] In one embodiment, the compression portion comprises alternating portions of increased width and reduced width.

[0015] In one embodiment, the compression portion is substantially cylindrical.

[0016] In one embodiment, the compression portion is cuboid.

[0017] In one embodiment, the compression portion defines at least one face that is generally concave.

[0018] In one embodiment, the elastomeric element comprises locating formations for locating the elastomeric element in position operationally.

[0019] In one embodiment, the locating formations comprise one or more selected from an aperture and a recess.

[0020] In one embodiment, the element comprises a cross-section being substantially adapted for insertion into a side bearing cage in use.

[0021 ] In one embodiment, the elastomeric element comprises an upper portion coupled to the compression portion, wherein the upper portion defines a friction face adapted for bearing against a bearing cap in use.

[0022] In one embodiment, the friction face comprises a bearing cap protrusion engagement.

[0023] In one embodiment, the friction face is angled with respect to the elongate axis of the element. [0024] In one embodiment, the upper portion and the compression portion composed of separate materials.

[0025] In one embodiment, the upper portion and the compression portion are integrally moulded.

[0026] In one embodiment, the alternating ribs of the compression portion define concertina formations.

[0027] In one embodiment, the compression portion defines an interior void.

[0028] The element may comprise a substantially rectangular cross-section and especially a substantially square cross-section. Alternatively, the element may comprise a substantially circular cross-section.

[0029] In another aspect, the invention may be said to consist in an elastomeric element for a railway car side bearing, the elastomeric element comprising a compression portion adapted to compress under load in use, wherein the compression portion comprises one or more ribs adapted for facilitating compression of the compression portion in use.

[0030] In one embodiment, the one or more ribs are two or more ribs.

[0031 ] In one embodiment, the two or more ribs are between 3 and 7 ribs.

[0032] In one embodiment, the two or more ribs are 4 ribs.

[0033] In one embodiment, the cross-section of the elastomeric element is configured for insertion into a side bearing cage in use.

[0034] In one embodiment, the elastomeric element further comprises an upper portion connected to the compression portion.

[0035] In one embodiment, the upper portion comprises a friction face adapted for bearing against a bearing cap in use.

[0036] In one embodiment, the friction face is angled with respect to the elongate axis of the element.

[0037] In one embodiment, the compression portion defines an interior void.

[0038] In one embodiment, the elastomeric element comprises a substantially rectangular cross-section.

[0039] In one embodiment, the elastomeric element comprises a substantially square cross-section. [0040] In one embodiment, the elastomeric element comprises a substantially circular cross-section.

[0041 ] In one embodiment, the elastomeric element is configured to compress elastically in use to between 20% and 99.99% of its uncompressed height.

[0042] In one embodiment, the elastomeric element is configured to compress elastically in use to between 50% and 99.99% of its uncompressed height.

[0043] In one embodiment, the elastomeric element is configured to compress elastically in use to between 70% and 99.9% of its uncompressed height.

[0044] In one embodiment, the compression portion comprises alternating portions of increased width and reduced width.

[0045] In one embodiment, the compression portion is substantially cylindrical.

[0046] In one embodiment, the compression portion is cuboid.

[0047] In one embodiment, the compression portion defines at least one face that is generally concave.

[0048] In one embodiment, the elastomeric element comprises locating formations for locating the elastomeric element in position operationally.

[0049] In one embodiment, the locating formations comprise one or more selected from an aperture and a recess.

[0050] In one embodiment, the locating formation comprises a bearing cap protrusion engagement.

[0051 ] In one embodiment, the upper portion and the compression portion are integrally moulded.

[0052] In one embodiment, the upper portion and the compression portion are composed of different materials.

[0053] In one embodiment, the upper portion and the compression portion are composed of the same material.

[0054] In one embodiment, the alternating ribs of the compression portion define concertina formations.

[0055] In one embodiment, the ribs define substantially semicircular concave and convex alternating profiles in cross-section along a vertical plane in use.

[0056] An elastomeric element for a railway car side bearing, the elastomeric element comprising a compression portion that is shaped to provide at least a plurality of compression characteristics, each compression characteristic being dependent on the extent to which the elastomeric element has been compressed.

[0057] In one embodiment, the compression portion is shaped to make increased contact with itself over a wider surface area to provide increased resistance at predetermined levels of compression.

[0058] An elastomeric element for a railway car side bearing, the elastomeric element comprising a compression portion defining alternating portions of increased width and reduced width.

[0059] In one embodiment, the ribs define substantially semicircular concave and convex alternating profiles in cross-section along a vertical plane in use.

[0060] Other aspects of the invention are also disclosed.

Brief Description of the Drawings

[0061 ] Notwithstanding any other forms which may fall within the scope of the present invention, a preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

[0062] Figure 1 shows a top perspective view of a prior art side bearing ;

[0063] Figure 2 shows a cutaway cross-sectional view of a prior art side bearing;

[0064] Figure 3 shows a cutaway cross-sectional view of an elastomeric element for a prior art side bearing;

[0065] Figure 4 shows a top perspective view of a first embodiment of an elastomeric element for a side bearing;

[0066] Figure 5 shows a front view of the first embodiment of an elastomeric element for a side bearing;

[0067] Figure 6 shows a bottom perspective view of a first embodiment of an elastomeric element for a side bearing;

[0068] Figure 7 shows a top view showing hidden detail of a first embodiment of an elastomeric element for a side bearing;

[0069] Figure 8 shows a side view showing hidden detail of a first embodiment of an elastomeric element for a side bearing;

[0070] Figure 9 shows a bottom view showing hidden detail of a first embodiment of an elastomeric element for a side bearing; [0071 ] Figure 10 shows a top perspective view of a second embodiment of an elastomeric element for a side bearing;

[0072] Figure 1 1 shows a front view showing hidden detail of the second embodiment of an elastomeric element for a side bearing;

[0073] Figure 12 shows a bottom perspective view of the second embodiment of an elastomeric element for a side bearing;

[0074] Figure 13 shows a top view showing hidden detail of the second embodiment of an elastomeric element for a side bearing;

[0075] Figure 14 shows a side view showing hidden detail of the second embodiment of an elastomeric element for a side bearing;

[0076] Figure 15 shows a bottom view showing hidden detail of the second embodiment of an elastomeric element for a side bearing;

[0077] Figure 16 shows a top perspective view of a third embodiment of an elastomeric element for a side bearing;

[0078] Figure 10 shows a side view showing hidden detail of the third embodiment of an elastomeric element for a side bearing;

[0079] Figure 18 shows a cutaway cross-sectional view of the third embodiment of an elastomeric element for a side bearing;

[0080] Figure 19 shows a top perspective view of a fourth embodiment of an elastomeric element for a side bearing; and

[0081 ] Figure 20 shows a cutaway cross-sectional view of the fourth embodiment of an elastomeric element for a side bearing.

Description of Embodiments

[0082] It should be noted in the following description that like or the same reference numerals in different embodiments denote the same or similar features.

[0083] With reference to the above drawings, in which similar features are generally indicated by similar numerals, an elastomeric element according to a first aspect of the invention is generally indicated by the numeral 10.

[0084] In one embodiment now described, there is provided an elastomeric element 10 for use in a side bearing (not shown) of a railway car (not shown).

[0085] With specific reference to figures 4 to 15, there is shown an elastomeric element 10 for a railway car side bearing. The element 10 is adapted for utilisation with existing railway car side bearings and, as will become apparent from the description below, the element 10 affords advantages including in providing for hunting control, compression characteristics and the like

[0086] Referring to figure 3, the element 10 comprises a compression portion 15 adapted to compress under load in use. The compression portion 15 generally defines alternating portions of increased width and decreased width when viewed in cross- section in a vertical plane. The alternating portions make up a plurality of ribs 1 1 adapted for facilitating compression of the compression portion 15 in use as will be described below.

[0087] In the embodiments shown, the ribs define substantially semicircular concave and convex alternating profiles in cross-section along a vertical plane in use. However, in another embodiment (not shown) it is envisaged that the ribs 1 1 can be concertina shaped, however the use of rounded edges is preferred in order to prevent stress concentrations and/or cracking of the elastomeric material at sharp internal ridges.

[0088] As such, in use, the element 10 is adapted for insertion into a standard side bearing cage. The element 10 comprises an upper portion 14 comprising or defining a friction face 12 adapted for bearing against a metal cap bearing of the railway car side bearing apparatus.

[0089] It is anticipated that the compression portion 15 of the elastomeric element 10 will, on initial compression, provide resistance to compression. This resistance to the initial compression will be dependent on the characteristics of the material, as well as on the size of the elastomeric element between the ribs at their smallest width.

[0090] As the elastomeric element 10 is further compressed, the portions of increased width will move closer to each other until, at a certain extent of compression, the portions of increased width will make increased contact with each other over a larger area, thereby increasing the resistance to compression.

[0091 ] In this way, by carefully choosing the distances between the alternating ribs and the size of the widths of the alternating portions of increased width and decreased width, specific compression characteristics can be engineered to be provided by the compression portion 15 at different levels of compression. For example, it may be desirous to provide a low initial (as an example within the first 10mm of compression) resistance to compression with maximum shock absorbency. This would be useful, for example when a railway car is moving in a straight line, and normal bumps and jolts on the railcar can be easily absorbed. Such a soft initial compression characteristic would also be useful to reduce "truck hunting" or hunting oscillation of the railway car truck. [0092] However, when the rail car moves around a bend, an increased load will be placed on the side bearing by the centrifugal forces acting on the railcar load, causing it to compress more (as an example more 10 mm of compression). An increased resistance to compression is required at this stage to prevent movement of the rail car load from centrifugal forces, making the railcar wallow outwardly on the bend, and potentially derailing the railcar.

[0093] It is envisaged that the elastomeric element will preferably be configured to compress elastically in use to between 20% and 99.99% of its uncompressed height, more preferably to between 50% and 99.99% of its uncompressed height, and most preferably to between 70% and 99.9% of its uncompressed height.

[0094] In this manner, in use, the compression portion 15 is adapted to enhance compression of the element 10 about the compression portion 15. Further, the element 10 provides advantages in being able to be manufactured as a single unit from a single type of material comprising a substantially uniform modulus of elasticity. In this regard, the element 10 may be manufactured from substantially "hard" elastomeric so as to provide robustness to the upper portion 14 wherein the compression ribs 1 1 yet allow for relatively low initial resistance to compression despite the element 10 being manufactured from the substantially hard elastomeric material.

[0095] The element 10 may comprise differing number of ribs 1 1 depending on the application. In a preferred embodiment, the element 10 comprises four ribs 1 1 as substantially given in figure 4.

[0096] As is apparent from the embodiment presented, each rib 1 1 is preferably substantially rounded, devoid of sharp angles and the like which could lead to stress fractures or other material failure. Upper portion 14 of the element 10 comprises a friction face 12 adapted for bearing against the metal bearing cap of the standard railway car side bearing in use. As is apparent, the fiction face 12 is substantially flat so as to provide a substantially uniform friction face.

[0097] Furthermore, the friction face 12 may, in one embodiment comprise a locating formation in the form of a metal cap protrusion engagement 13 adapted for engaging a protrusion of a metal cap in use so as to substantially prevent the accidental relocation or disorientation of the element 10.

[0098] As is also apparent, the friction face 12 can be angled with respect to the elongate axis of the element 10 so as to engage the angled face of the metal cap in use. [0099] Referring to figure 6, in one embodiment the compression portion 15 defines an interior void 16. Such a void may assist the compression portion 15 in compressing in use. However, it should be noted that in certain embodiments the element 10 may be solid, devoid of any interior void 16.

[00100] In the embodiments shown in figures 4 - 15 , the element 10 is generally cuboid in shape and comprises a substantially rectangular cross-section and preferably a substantially square cross-section. In this regard, it is noted that the element 10 further comprises a cross-section being substantially adapted for insertion into the side bearing cage in use. In this manner, and as is apparent from figure 4, at least one of the walls of the element 10 can be generally concave or inwardly dished so as to conform to the interior contours of the side bearing cage in use.

[00101 ] Referring to figures 16-18 and 19-20 there are shown two alternative embodiment of the element 10 wherein, as is apparent, the cross-section of the element 10 is substantially circular, and the compression portion 15 is generally cylindrical in shape. In the embodiments shown in figure 19 - 20, the locating formation is in the form of a recess

[00102] In these alternative embodiment, it should be noted that the element 10 does not include an upper portion 14 comprising the friction face 12. However, in certain embodiments, the element 10 can comprise the upper portion 14, including the friction face 14 which may similarly be angled with respect to the elongate axis of the element 10 as described above.

Interpretation

Embodiments:

[00103] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments. [00104] Similarly it should be appreciated that in the above description of example embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the Detailed Description of Specific Embodiments are hereby expressly incorporated into this Detailed Description of Specific Embodiments, with each claim standing on its own as a separate embodiment of this invention.

[00105] Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

Different Instances of Objects

[00106] As used herein, unless otherwise specified the use of the ordinal adjectives

"first", "second", "third", etc., to describe a common object, merely indicate that different instances of like objects are being referred to, and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner.

Specific Details

[00107] In the description provided herein, numerous specific details are set forth.

However, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Terminology

[00108] In describing the preferred embodiment of the invention illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar technical purpose. Terms such as "forward", "rearward", "radially", "peripherally", "upwardly", "downwardly", and the like are used as words of convenience to provide reference points and are not to be construed as limiting terms.

[00109] For the purposes of this specification, the term "elastomer" and "elastomeric" shall be construed to mean a general term for a wide range of synthetic or semisynthetic polymerization products, and generally consisting of a hydrocarbon- based polymer, and shall include but not be limited to rubbers.

Comprising and Including

[001 10] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

[001 1 1 ] Any one of the terms: including or which includes or that includes as used herein is also an open term that also means including at least the elements/features that follow the term, but not excluding others. Thus, including is synonymous with and means comprising.

Scope of Invention

[001 12] Thus, while there has been described what are believed to be the preferred embodiments of the invention, those skilled in the art will recognize that other and further modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as fall within the scope of the invention. For example, any formulas given above are merely representative of procedures that may be used. Functionality may be added or deleted from the block diagrams and operations may be interchanged among functional blocks.

Steps may be added or deleted to methods described within the scope of the present invention.

[001 13] Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

Industrial Applicability

[001 14] It is apparent from the above, that the arrangements described are applicable to the railway industries.