1 An improved railway bogie and method of manufacturing the same BACKGROUND OF THE INVENTION The present invention is directed to a further improvement of the swing-motion truck (or bogie) disclosed in US 5,027,716 (Weber, et al), which is incorporated by reference herein. 5 The truck disclosed in the above-identified patent sought to improve on the type of truck disclosed in US 3,670,660 (Weber, et al) which is a conventional swing-motion truck including a transverse platform or transom spanning laterally across the width of the truck, with each end of the transom being supported on a respective rocker seat and held in alignment via a plurality of upstanding bosses received in apertures formed in the ends of the transom proper. In particular, 0 the improvement related to the replacement of the transom with rigid radius, or transverse, rods interconnecting the parallel side frames of the truck by direct coupling to the rocker seats associated with the side frames. The rods also included horizontal cross-stabilizer elements, together forming a "shear adapter" which replaced the transom. The method of connecting the cross-stabilizer elements between the two rods, as taught in the patent, is through use of metal 5 brackets wrapped around elastomeric bushings and secured directly to the cross-stabilizer plate by bolts, and alternatively, through use of a cross-stabilizing element including rounded ends adapted to wrap around the rods and welded thereto. These features, among others, overcame some of the deficiencies associated with the conventional-type trucks utilising transoms, including the overall cost, weight, and reliability of 20 the trucks in that transoms often experienced fatigue cracks. A further benefit was that the shear adapter could be easily removed without disassembling the entire truck. The present inventors have identified a number of further problems associated with the use of such shear adapter assemblies, in particular, in their configuration and in the way they are currently manufactured and assembled. Because of the significant expense associated with 25 manufacturing and commissioning such trucks/bogies, even small improvements to their design, configuration and/or method of manufacture often go a long way to reducing labour and associated costs. It is therefore an object of the present invention to overcome at least some of the aforementioned problems or provide the public with a useful alternative.
2 SUMMARY OF THE INVENTION Therefore, in one form of the invention there is provided a railway bogie or truck comprising: a first side frame and a second side frame; 5 a pair of front and rear wheel-axle sets, which each of said first and second side frames being swingingly coupled to said pair of axle sets on a lateral side of said pair of wheel-axle sets, said first side frame being disposed on one lateral side and said second side frame being disposed on the other lateral side of said truck, each of said first and second side frames also supporting a rocker seat including a vertical, downwardly extending bracket having associated therewith 0 receiving apertures proximate forward and rear ends thereof; a shear adapter assembly including two parallel tie rods adapted to rigidly connect said first and second side frames, said pair of tie rods being spaced apart, the first and second ends of one said tie rod being aligned with said forward receiving apertures of said pair of rocker seat brackets, and the first and second ends of the other said tie rod being aligned with said rear receiving 5 apertures of said rocker seat brackets, each said tie rod including a longitudinal axis and end flanges, each end flange having an internally threaded aperture extending along said tie rod longitudinal axis, said aperture being adapted for engagement with the outer thread of an end bolt extending through said corresponding rocker seat bracket aperture to thereby secure said tie rod end to said bracket; and 0 at least one cross-stabiliser means interconnecting said two tie rods together at approximately corresponding intermediate sections of said two tie rods, said cross-stabilizer means extending substantially transverse to said tie rod longitudinal axes and in substantially a single plane to facilitate welding of ends thereof to said intermediate sections, whereby said cross-stabiliser means increases stiffness to parallelogramming. 25 Preferably said end bolt further extends through a coaxially aligned locking plate, and a first centre bonded mounting and holding ring on an outer side of said rocker seat bracket, and a second centre bonded mounting and holding ring on the inner side of said rocker seat bracket between the bracket and the tie rod flange. In preference said cross-stabiliser means is in the form of a substantially rectangular plate 30 extending in a single plane, said plate having outwardly diverging rounded ends, edges of which are adapted for welding to said tie rod intermediate sections.
3 In a further form of the invention there is provided a method of manufacturing a railway bogie or truck including the steps of having a first side frame and a second side frame, a pair of front and rear wheel-axle sets, which each of said first and second side frames being swingingly coupled to said pair of axle sets on a lateral side of said pair of wheel-axle sets, said first side 5 frame being disposed on one lateral side and said second side frame being disposed on the other lateral side of said truck, each of said first and second side frames also supporting a rocker seat including a vertical, downwardly extending bracket having associated therewith receiving apertures proximate forward and rear ends thereof, said method including the steps of: forming a pair of tie rods of a length corresponding substantially to the spaced apart distance 0 between said rocker seat brackets, whereby each tie rod includes a longitudinal axis and end flanges, each end flange having an internally threaded aperture extending along said tie rod longitudinal axis; forming a cross-stabiliser plate having a single plane; interconnecting said pair of tie rods in a parallel configuration to form a shear adapter assembly 5 by welding said cross-stabiliser plate at ends thereof to intermediate sections of each of said tie rods; securing the ends of a first tie rod to each rocker seat bracket using end bolts having an outer thread adapted to extend through said bracket forward apertures to engage the internal thread of said tie rod flanges upon tightening of said end bolts; and 0 securing the ends of the second tie rod to each rocker seat bracket using end bolts having an outer thread adapted to extend through said bracket rear apertures to engage the internal thread of said tie rod flanges upon tightening of said end bolts. In a still further form of the invention there is provided a railway bogie or truck manufactured according to the above method. 25 BRIEF DESCRIPTION OF THE DRAWINGS 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 advantages and principles of the invention. In the drawings: 30 Figure 1 illustrates a perspective view of a bogie, an enlarged perspective view of a radius rod of the bogie shear adapter and rocker seat, and an enlarged, exploded perspective view of the 4 connection means between the radius rod and the rocker seat in accordance with the present invention; and Figure 2 illustrates an enlarged perspective view of a radius rod of the bogie shear adapter and rocker seat of the bogie of Figure 1 and an enlarged top view of one end of the shear adapter 5 including a pair of radius rods interconnected by a welded cross-stabilizing element in accordance with the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS The following detailed description of the invention refers to the accompanying drawings. Although the description includes exemplary embodiments, other embodiments are possible, and 0 changes may be made 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. Referring now to the drawings in greater detail, an improved swing-motion truck or bogie 10 is shown in Figure 1. The truck 10 includes a pair of parallel side frames 12, each side frame 5 12 operating as a swing hanger, and has a forward end 14 swingingly mounted on a bearing adapter of a forward axle-set 16 in the conventional swing-motion truck manner, and the rearward end 18 is mounted in similar fashion to the rear axle-set 20. The central or middle portion of each side frame 12 is also relatively, rockingly mounted with respect to a rocker-seat 22, as shown more clearly in the middle drawing of Figure 1. 20 The side-frame rocker-seat 22 provides a lower spring-seat for the suspension and control springs, the upper ends of which suspension springs support a respective end of the transverse bolster 24 of the bogie. The suspension springs are indicated generally by reference 26 in Figure 1, the lower ends of which are supported directly upon the upper flat surface face of the rocker seat 22. 25 The various additional features of the bogie 10 which are considered to be known to those skilled in the art and which do not contribute to the present invention will not be described in more detail herein. The reader is directed towards the two prior published patents mentioned in the preamble of the invention for a more detailed description of those features, such as the configuration of the side-frame's tension member (not shown) for example. The present 5 Applicant is also the owner of a co-pending patent application directed towards an improved passive steering system which is present in the bogie 10, but which will not be described. As described above, the transom interconnection employed by conventional swing motion trucks was eliminated and replaced by a shear adapter assembly including two transverse 5 support or radius rods. A similar shear adapter assembly is present in the bogie 10 of the present invention including rods 28, 30 used to rigidly interconnect the parallel side frames by directly interconnecting the two rocker-seats 22 thereof. The present invention relates in particular to the means of connection 32 between the rods 28, 30 with the rocker seats 22, and the configuration of cross-stabilising elements or shear adapters 34 which extend between the rods 28 and 30 and 0 which are described in more detail below. Each rocker-seat 22 includes an anchor bracket 36 which extends substantially vertically downwardly between which the transverse rod pair 28, 30 is adapted to extend. The means of connection 32 between each rod of the shear adapter assembly and the anchor bracket 36 is best seen in the top image of Figure 1. Each rod terminates in an end flange 38 including a hollow 5 internally threaded portion (not shown) adapted to receive a correspondingly threaded outer portion of an end bolt 40 for engagement therewith. The end bolt 40 is adapted to extend through a locking plate 42 and a centre bonded mounting 44 and holding ring 46 on the outer side of the anchor bracket 26, through an aperture (not shown) in the anchor bracket 36, and through a centre bonding mounting 48 and holding ring 50 on the opposed inner side of the anchor bracket 0 36 before engaging the end flange 38 of the rod. The skilled addressee would realise that when the end bolt 40 is tightened, all of the components are urged together, some compressed, to form an extremely strong and robust connection between the ends of each rod pair and the rocker seat anchor brackets. The skilled addressee would also realise the ease at which the rods 28, 30 can be connected to the anchor 25 brackets 36 by simple tightening of the end bolts 40 from the outer side of the anchor brackets 36. Although not shown, each end bolt 40 also includes a double tab washer disposed between a head of the bolt and the locking plate 42. It is to be understood that this connection means 32 is intended to be used at all four connection points between the ends of each radius rod 28 and 30 of the shear adapter and the downwardly extending anchor bracket 36 of each opposed rocker 30 seat 22.
6 The radius rods 28, 30 of the shear adapter are also provided with horizontal cross stabilizer elements 34 disposed towards the ends of the radius rods adjacent each of the rocker seats 22. In the preferred embodiment, each cross-stabilizer is a flat, horizontal rectangular plate having diverging rounded ends of slightly increased width to that of a centre portion of the plate, 5 as shown in Figure 2, the ends adapted for welding directly along the approximate mid-portions of each rod 28, 30. The present inventors have found that the combination of using cross stabiliser elements welded to the rods in this way, together with the improved means of connection 32 between the radius rods 28, 30 and the rocker seats 22, results in an overall improved shear adapter assembly. 0 In particular, less material and parts are required in that the cross-stabilisers 34 are flat and extend between the rods in a single plane for welding thereto, meaning that manipulation of their shape (for example to journal around each rod or to accommodate use of mechanical fasteners) is no longer required. The means for connecting the rods to the rocker seats 22 constitutes an improvement in that their configuration is far less complex than conventional 5 shear adapter-rocker seat connections, and the end result is a stronger and more robust connection with decreased cost, weight, and likelihood of fatigue cracking. 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 0 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 accorded the full scope of the claims so as to embrace any and all equivalent devices and apparatus. In any claims that follow and in the summary of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprising" is 25 used in the sense of "including", i.e. the features specified may be associated with further features in various embodiments of the invention.