AU2012101705A4 - Bogie cross-link assembly including anti-vibration liner - Google Patents

Abstract

The present invention relates to an anti-vibration liner for use in railway bogies and, in particular, to one or more low friction liners for preventing diagonal cross links of a bogie to flap or vibrate, thereby reducing noise and cross link wear. 70 (0t 7a202 x12 r,4, S(

Description

1 Bogie cross-link assembly including anti-vibration liner FIELD OF THE INVENTION The present invention relates to a railway bogie cross-link assembly including an anti-vibration liner and, in particular, to one or more plastic liners for preventing diagonal cross links of a bogie to flap or vibrate, 5 thereby reducing noise and cross link wear. The invention further relates to a railway bogie incorporating the same. BACKGROUND OF THE INVENTION Flexible diagonal links, also known as diagonal linkages or struts, have been used for many years in railway bogie or truck design to provide a connection between laterally spaced side frames such that 0 relative longitudinal movement therebetween is opposed. Such links typically include a bushed connection to the side frames at each of their extremities to also provide a controlled flexibility in shear relative to the bogie assembly. The diagonal links often cross each other at the centre of the bogie by one passing through the other such that one link has a hollow portion through its centre, or includes an appropriately configured central 5 bracket, which allows for the other link to extend through. Such configurations result in a clearance between the two links which often causes the links to flap or vibrate. It has been recognised that such movement can cause wear at this central interface and also at the extremities of each link, as well as significant noise due to rattling. SUMMARY OF THE INVENTION 20 In one aspect, the present invention provides a bogie cross link assembly including: first and second diagonally extending cross links, said first cross link including an upper, downwardly directed surface and a lower, upwardly directed surface defining a passage through which the second cross link is adapted to pass, the spaced apart distance between the upper and lower surfaces being such that when the second cross link extends through the passage, a clearance exists between an upper surface 25 of the second cross link and the upper, downwardly directed surface of the first cross link, and between a lower surface of the second cross link and the lower, upwardly directed surface of the first cross link; and at least one liner adapted to fill said clearances. The liner, which may be made of a resilient, low friction material, thus acts as a vibration dampener and prevents contact between the first and second cross links at the interface at which the links cross. 30 Vibration is thus minimised, and so wear at this interface as well as at the extremities of the cross links is reduced. The liners also provide for reduced noise.

2 In an embodiment, said first cross link includes a central bracket having upper and lower plate members which include said upper, downwardly directed and lower, upwardly directed surfaces respectively. In an embodiment, the bracket includes two opposed liners each in the form of substantially U-shaped members including a flat base and two low upstanding walls extending from said base and defining a 5 channel adapted to receive each of said upper and lower plate members such that the second cross link is sandwiched between the flat base of each liner and the upstanding walls of each liner extend along sides of each the upper and lower plates. In an embodiment, said liner is made of a low friction plastic material such as polytetrafluoroethylene PTFE. 0 In another aspect, the present invention provides a railway bogie including: two laterally spaced apart side frames connected by a central bolster; first and second diagonal cross links extending between said side frames and configured such that they cross each other at substantially a central location between the side frames, said cross links being resiliently associated with the side frames; 5 wherein said first cross link includes an upper, downwardly directed surface and a lower, upwardly directed surface at said central location defining a passage through which the second cross link is adapted to pass, the spaced apart distance between the upper and lower surfaces being such that when the second cross link extends through the passage, a clearance exists between an upper surface of the second cross link and the upper, downwardly directed surface of the first cross link, and between a lower surface of the 0 second cross link and the lower, upwardly directed surface of the first cross link; and at least one low friction liner adapted to fill said clearances. BRIEF DESCRIPTION OF THE DRAWING FIGURES The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several implementations of the invention and, together with the description, serve to explain the 25 advantages and principles of the invention. In the drawings: Figure 1 illustrates a side view of a railway bogie or truck configured in accordance with an embodiment of the present invention; Figure 2 illustrates a cutaway top view of the bogie of Figure 1; Figure 3 illustrates a cross sectional view along the axis of an outer diagonal link including anti 30 vibration liners configured according to an embodiment of the present invention; Figure 4 illustrates a cross sectional view along the axis of the inner diagonal link of Figure 3; and 3 Figure 5 illustrates a perspective view of the arrangement of Figures 3-4. DETAILED DESCRIPTION OF THE EMBODIMENT(S) The following detailed description of the invention refers to the accompanying drawings. Although the description includes exemplary embodiments, other embodiments are possible, and changes may be made 5 to the embodiments described without departing from the spirit and scope of the invention. Wherever possible, the same reference numbers will be used throughout the embodiments and the following description to refer to the same and like parts. The present invention relates to improvements in railway bogie (or truck) design and, in particular, to an improved bogie 10 including at least one anti-vibration liner 12 at the interface between the bogie 0 diagonal cross links 14. The liners 10 of the present invention serve to reduce wear at this interface and also at the extremities of each link, and abate noise that would otherwise be produced from cross link rattle. Figures 1-2 illustrate a bogie 10 according to an embodiment with various standard components including two side frames 16, a transverse bolster 18 supported above springs 20, wheel sets 22, wheel axles 24, 5 and load supporting saddles 26. Such components are considered known in the art and as such are not described in detail herein. The bogie 10 further includes strut plates 28 extending outwardly from each side frame and adapted to support each end of the diagonal cross links 14 about spigot assemblies 30 associated with each plate 28. The cross links thereby extend though apertures in the side frames and cross at the middle of the bogie 0 above (or through) the bolster. It is to be understood that the present invention is not intended to be limited to the use of strut plates, and that the diagonal links may well be attached to other parts of the bogie, such as to a sub-frame for example. As shown most clearly in Figure 2, the links 14 may cross each other at approximately the centre of the bolster 18. The cross links may not be identical in that one may be configured to extend through the other, 25 so one of the cross links includes either a hollowed out centre portion (not shown) or, as embodied herein, a bracket 32 at the centre of the link configured to allow the other link to pass through. In the embodiment shown, the bracket 32 includes an upper and lower flat plate 34 and 36 respectively which are in a spaced apart and parallel relationship to accommodate the second link there between. As mentioned in the preamble, previous arrangements of this type have been known to result in flapping 30 and vibration of the links along their length which in turn leads to excessive noise, and also increased wear at the interface and extremities of the links, and hence a shorter life span. The present invention seeks to overcome these problems by introducing one or more liners 12 which separate the cross links and 4 thereby prevent vibration and direct contact between the links. The liners, which are preferably made of a suitably resilient material such as plastic, therefore act as vibration dampeners. In an embodiment, the liners are made of low-friction polytetrafluoroethylene (PTFE). Reference to "inner link" is intended to be the link which passes through the bracket 32, while reference 5 to "outer link" is intended to be the link including bracket 32 through which the inner link passes. An embodiment of a liner is shown in Figures 3 and 4 which proposes the use of two opposed, substantially U-shaped liners 12 adapted to accommodate plates 34 and 36 such that a base portion 38 of each U-shaped liner is sandwiched between the inner link 14 and respective plates 34 and 36. If necessary, an appropriate adhesive may be used to attach the liners to each plate. Each U-shaped liner 0 also includes two upright side portions 40 and 42 which extend along the sides of each plate 34 and 36. Figure 5 shows a perspective view of this embodiment. It is to be understood that other liner embodiments could also be implemented, provided a clearance is maintained between the inner link and the bracket through which it extends, and that movement is not restricted to only one direction. 5 The liner 12, depending on its material and other factors, may wear over time by virtue of the cross link movement, and thus may require replacement. The liner may be configured to be easily removable from around the inner link after it has been sufficiently worn, with new liners configured to be easily fitted thereto. The skilled addressee would now realise the various advantages of the present invention. There is 0 provided, according to an embodiment, a bogie having diagonal cross links which are resiliently connected at their extremities to the bogie side frames, or as per the embodiment shown, strut plates associated therewith. Where in the past such cross links have suffered from wear both at the centre of the links where they cross and at their ends due to vibration, the cross links of the present invention are separated using at least one anti-vibration liner. This results in reduced vibration and hence longer life of 25 these components, as well as reduced noise. Further advantages and improvements may very well be made to the present invention without deviating from its scope. Although the invention has been shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope and spirit of the invention, which is not to be limited to the details disclosed herein but is to be 30 accorded the full scope of the claims so as to embrace any and all equivalent devices and apparatus.

Claims (5)

1. A bogie cross link assembly including: first and second diagonally extending cross links, said first cross link including an upper, downwardly directed surface and a lower, upwardly directed surface defining a passage through 5 which the second cross link is adapted to pass, the spaced apart distance between the upper and lower surfaces being such that when the second cross link extends through the passage, a clearance exists between an upper surface of the second cross link and the upper, downwardly directed surface of the first cross link, and between a lower surface of the second cross link and the lower, upwardly directed surface of the first cross link; and 0 at least one liner adapted to fill said clearances.

2. A bogie cross link assembly according to claim 1 wherein said first cross link includes a central bracket having upper and lower plate members which include said upper, downwardly directed and lower, upwardly directed surfaces respectively.

3. A bogie cross link assembly according to claim 2 wherein the bracket includes two opposed liners 5 each in the form of substantially U-shaped members including a flat base and two low upstanding walls extending from said base and defining a channel adapted to receive each of said upper and lower plate members such that the second cross link is sandwiched between the flat base of each liner and the upstanding walls of each liner extend along sides of each the upper and lower plates.

4. A bogie cross link assembly according to any one of the above claims wherein said liner is made 0 of a plastic material.

5. A railway bogie including: two laterally spaced apart side frames connected by a central bolster; first and second diagonal cross links extending between said side frames and configured such that they cross each other at substantially a central location between the side frames, said cross links 25 being resiliently associated with the side frames; wherein said first cross link includes an upper, downwardly directed surface and a lower, upwardly directed surface at said central location defining a passage through which the second cross link is adapted to pass, the spaced apart distance between the upper and lower surfaces being such that when the second cross link extends through the passage, a clearance exists 30 between an upper surface of the second cross link and the upper, downwardly directed surface of the first cross link, and between a lower surface of the second cross link and the lower, upwardly directed surface of the first cross link; and at least one low friction liner adapted to fill said clearances.