GB1573326A - Railway bogies - Google Patents

Description

PATENT SPECIFICATION

( 11) 1 573 326 ( 21) ( 62) ( 31) Application No 12446/79 ( 22) Filed 22 Feb 1977 Divided Out of No 1573324 Convention Application No's 726943 744620 ( 32) Filed 27 Sep 1976 24 Nov 1976 in ( 33) United States of America (US) ( 44) Complete Specification Published 20 Aug 1980 ( 51) INT CL 3 B 61 H 13/24 ( 52) Index at Acceptance F 2 E 2 M 1 B 4 C 2 2 M 1 B 5 A 2 2 M 1 E 4 AB F 2 F BJ ( 54) RAILWAY BOGIES ( 71) We, GENERAL STEEL INDUSTRIES INC, a Corporation organised and existing under the laws of the State of Delaware, United States of America, of 11 South Meramec, St Louis, State of Missouri 63105, United States of America, de hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the

following statement:

This invention relates to railway bogies.

The present specification is a divisional from our U K Patent Specification No 1573324 ( 7402/77), to which reference is directed.

Reference is also directed to U K Patent Specification Nos 1573325 ( 7912445) and

1573327 ( 7912447), which are divisionals from our U K Patent Specification No.

1573324 ( 7402177).

According to the present invention there is provided a railway bogie comprising a pair of wheel and axle assemblies each having a pair of railway flanged wheels rigidly mounted on the ends of an axle, a bogie frame supported from said wheel and axle assemblies and accommodating relative turning movements of said wheel and axle assemblies in the horizontal plane for steering, said wheel and axle assemblies having steering means causing them to pivot in opposite senses on curved track, a brake system comprising brake shoes engageable with the respective wheel treads, means swingably supporting each brake shoe from said bogie frame, an extensible rod device connecting the brake shoes at each side of the bogie frame for causing them to be separated longitudinally of the bogie and forced into braking engagement with the respective wheel treads, each said extensible rod device comprising a longitudinally extending cylinder and piston assembly connected at its respective ends to said brake shoes, and a hydraulic fluid interconnection between said cylinders at opposite sides of the bogie, whereby to positively equalize braking pressure on the separate brake shoes on both sides irrespective of differences in the longitudinal spacing of the wheels on the opposite sides of the bogie resulting from steering action of said wheel and axle assemblies.

Specific embodiments of the invention will now be described by way of example with reference to the accompanying drawings, in which:

Figure 1 is a plan view of a four wheel railway car bogie embodying the invention.

Figure 2 is a longitudinal vertical sectional view taken along line 2-2 of Figure 1.

Figure 3 is a transverse vertical sectional view taken along line 3-3 of Figure 1.

Figure 4 is a generally horizontal sectional view taken along line 4-4 of Figure 2.

Figure 5 is a plan view of a modified form of the bogie embodying the invention.

Figure 6 is a longitudinal vertical sectional view taken along line 6-6 of Figure 5.

Figure 7 is a transverse vertical sectional view taken along line 7-7 of Figure 5.

Figure 8 is a side elevational view, partially sectionalized similarly to Figures 2 and 6, of a bogie embodying a third form of the invention.

Figure 9 is an enlarged fragmentary elevational view, partially sectionalized along line 9-9 of Figure 10, of a pedestal and the associated primary suspension arrangement of the bogie illustrated in Figure 8.

Figure 10 is an enlarged top view partially sectionalized along line 10-10 of Figure 9.

The bogie illustrated in Figures 1-4 has a pair of spaced wheel and axle assemblies each comprising railway flanged wheels mounted in gauged pairs on the ends of the respective axles 2 and 3 The effective conicity of the wheel tread profiles is sufficient to effect self-steering of each wheel and axle assembly by means of the differen( 19) 1 573 326 tial effect between the wheel diameters of the outer and inner wheels on curved track and is substantially greater than the standard conicity of 1:20 or 0 05, preferably being between 1:10 and 1:5 Inboard of the wheels, each of the axles 2 and 3 mounts, adjacent each wheel, an axle bearing 5 on which is mounted an adapter 7 of generally isosceles trapezoidal shape in elevation, the fore and aft surfaces 9 of each adapter 7 being V-shaped in plan with their apices pointing away from the associated bearings.

Correspondingly V-shaped elsastomeric pad devices comprising metal plates 11 bonded to similarly shaped elastomeric pads 13 are secured to fore and aft surfaces 9 of adapter member 7 and their outermost plates 11 are secured to inner surfaces 15 of spaced vertical legs 17 connected by horizontal top members 19 to form downwardly open yokes, surfaces 15 being inclined parallel respectively to fore and aft surfaces 9 of the adapters and being of corresponding concanve V-shape in plan Preferably the lower extremities of yoke legs 17 are connected by a binder or tie bolt 21 to oppose any tendencies toward spreading The top member 19 of each yoke is of convex V-shape with its apex longitudinal of the bogie and mounts a V-sesction elastomeric sandwich device with its apex somewhat elongated lengthwise of the bogie and comprising a pair of flat elastomeric pads 23 bonded on their respective top and bottom surface by flat metal plates 25.

A rigid bogie frame, comprising longitudinally extending transversely spaced side members 27 positioned generally transversely inwardly of wheels 1 and connected by a pair of longitudinally spaced transversely extending transom members 29, symmetrically disposed fore and aft of the transverse center line of the bogie, is supported at the end portions 31 of side members 27 on elastomeric sandwich devices 23, 25, the lower surfaces of the end portions of frame side members 27 being correspondingly of concave V-shape and arranged for securement to top plate 25 of the sandwich devices In order to minimize the overall height of the bogie, the central portion 33 of each of the side members 27 is depressed to a substantially lower level than the end portions 31.

With the bogie structure as thus far described, it will be evident that yokes 17, 19 will be vertically resiliently supported on adapters 7 by reason of the yieldability in vertical shear of elastomeric pad devices 11, 13 but that relative longitudinal and lateral movements of the yokes relatuve to the axle bearing adapter 7 will be effectively resisted by the resistance of the elastomeric pad devices 11, 13 to compression transversely and longitudinally of the bogie However, limited movement of the yokes 17, 19 longitudianlly of the bogie sufficient to accommodate limited yaw of axles 2 and 3 with respect to bogie frame 27-33 will be accommodated by yielding in shear of elastomeric sandwich devices 23, 25 longitudinally of the bogie and lateral movements opposed by the resistance of pads 23 to compression transversely of the bogie.

For preventing excessive movement of the axles, longitudinally of the bogie, the end portions 31 of bogie frame side members are bent downwardly at 35 longitudinally outboard of the respective yokes 17, 19 and are formed at their lower extremities with vertical safety stop surfaces 37 spaced from outer legs 17 longitudinally of the bogie but engageable with opposed vertical surfaces 39 on the outer legs 17 of the respective yokes Longitudinally inboard of the bogie from the respective yokes, the bogie frame is formed with brackets 41 having similarly vertical safety stop surfaces 43 in similarly spaced opposing relation with longitudinally inboard vertical surfae 39 of inboard yoke legs 17.

Substantially at axle level, inboard legs 17 of the yoke are formed with inwardly extending clevis-like brackets 45 and the diagonally opposed brackets 45 are connected by diagonal links 47, 49, the ends of which are pivotally secured to the respective brackets 45 Diagonal links 49 couple the wheel induced steering movements of the individual wheel and axle assemblies to cause their symmetrical turning movements in opposite direction on curved track and co-operate with the resistance offered by the longitudinally acting pads 23 to oppose hunting movements of the wheel and axle assemblies on tangent track.

For supporting vehicle body underframe U and accommodating swivel movements of the bogie with respect thereto and lateral movements of the underframe with respect to the bogie so as to cushion the body from transverse irregularities in the track structure, depressed central portions 33 of frame side members 27 are extended transversely outboard at 51 to form brackets for supporting upright spring devices generally indicated at 53 constructed to yield vertically and in longitudinal and lateral shear for accommodating vertical cushioning, swivel and lateral cushioning movements of the supported underframe U with respect to the bogie.

For resiliently limiting lateral movements of underframe U on the bogie, laterally inwardly facing elastomeric bumpers 54 are mounted on upstanding brackets 56 on the central portions of the frame side members 27 and oppose, in spaced relation, depending brackets 58 on underframe U.

For transmitting traction and braking 1 573 326 forces between the bogie and underframe, a Watts linkage comprising a generally transverse lever 55 fulcrumed at the center of the bogie on a pin 57 depending from underframe U and connected at its ends by longitudinally extending anchor devices 59 to upstanding brackets 61 on the bogie frame transoms 29 is provided.

For braking the bogie irrespective of axle yaw, the brake rigging at each side comprises a pair of substantially vertical brake levers 61 pivotally depending from outboard brackets 63 on the bogie frame side members 29 and pivotally mounting intermediate their ends brake heads 65 carrying the usual shoes 67 engageable with the adjacent wheel treads At their lower ends levers 61 are connected respectively to a pair of aligned rods 69 and 71 extending longitudinally of the bogie, rod 69 mounting a hydraulic cylinder 73 and rod 71 being connected to a piston 75 in cylinder 73 The cylinders 73 on opposite sides of the bogie are connected by a transverse hydraulic conduit 77 communicating via a tee connection 79 with a master cylinder 81, the piston 83 of which is actuated by the power brake beams on the car, e g air brake cylinder 85 Because of the interconnection by means of conduit 77 of the hydraulic cylinders at each side, the brakes at both sides will be equalized irrespective of yaw of the axles on curved track when the wheel treads on the inside of the curve would be substantially closer to each other than those on the outside of the curves and thus even under such yaw conditions in which the axles are substantially radial of the curve, equal brake pressure would be applied to each wheel tread.

Operation of the bogie is as follows:

While moving along tangent track, all tendencies of the individual axles to oscillate about vertical axes or to move lengthwise with respect to the bogie frame, are resisted by the resistance of elastomeric pads 23 to shear longitudinally of the bogie and are limited by stops 37 and 43 in co-operation with the outer vertical surfaces of yoke legs 17, and diagonal links 47 and 49 co-operate with the resistance offered by elastomeric pads 23 to oppose any such oscillation or hunting movements of the individual axles.

In the absence of such movement by the individual axles, the bogie frame is similarly insulated against such oscillation or hunting movements, making unnecessary the provision of damping means between the bogie frame and the supported car body underframe thus facilitating the use of the bolsterless constructon of the type disclosed, in which the underframe is supported on the bogie frame by combination pneumatic and elastomeric spring devices yieldable vertically, laterally and longitudinally to accommodate relative cushioning and swivelling movements of the body and the draft connection between the body and the bogie frame can consist of a device such as the disclosed Watts linkage which offers complete freedom of movement vertically and laterally and in swivel, but not longitudinally so as to form a substantially unyielding draft connection between the bogie and body As the truck moves along curved track, the conically profiled wheel treads, by reason of the engagement of different diameters of the inner and outer wheel treads with the respective track rails, induce selfsteering swiveling movements in the individual wheel and axle assemblies, which are thereby positioned substantially radially with respect to the track curvature The coupling of the wheel ahd axle assemblies to each othser accommodate symmetrical swiveling movement in opposite senses of the individual wheel and axle assemblies and thus avoids interference with the selfsteering capability of the respective wheel and axle assemblies on curved track, but damps hunting tendencies and counteracts hunting of the wheel and axle assemblies by causing swiveling movements of either wheel and axle assembly to produce opposite swiveling movements of the other wheel and axle assembly as the bogie moves along tangent track As the bogie moves from curved to tangent track, the interconnecting links assist the self-steering capacity of the axles and elastomeric pad devices 23, 25 to restore the axles to their normal tangent track positions and maintain them therein.

By reason of the inboard location of fthe longitudinally acting axle restraint devices, i.e, elastomeric pad devices 23, 25, the resistance they offer to movement of the axles purely longitudinally of the bogie frame is just as great as if pads of equal stiffness were positioned laterally outboard of the wheels but the resistance that the elastomeric pad devices at opposite sides of the bogie offer to steering yaw movements of the axles is advantageously minimized by virtue of their close spacing transversely of the bogie and the consequent shortening of the transverse arm through which they act as a couple to oppose yaw.

When the brakes are actuated, for example by applying air to the air cylinder 85 and thereby actuating piston 83 of hydraulic master cylinder 81 due to the interconnection between the brake cylinders at opposite sides of the bogie, the pressure in each cylinder will be equalized causing the brake shoes 67 to be applied with equal force to the wheel treads irrespective of differences in the longitudinal spacing of the wheels at the opposite sides of the bogie when the boggie is operating on curved track.

In Figures 5-7, the same numerals as are used in Figures 1-4 are used to denote 1 573 326 identical or substantially identical elements, the principal difference between the bogie of the first embodiment and that of Figures 5-7 being in the primary suspension whereby the bogie frame is supported from the axles.

In this embodiment, the axle bearings 5 are each respectively mounted in a rectangular adaptor 81 formed with fore and aft shelves or wings 83 supported by appropriate gusset 85 and mounting upright spring means comprising flat elastomeric pad devices 86 seated on wings 83 and supporting spring seats 87 carrying coil springs 88, which underlyingly engage the bottom surface of end portions 91 of the bogie frame side members 27 a vertical movements of the frame with respect to the axles and yawing movements of the axles with respect to the bogie frame being accommodated and yieldingly resisted respectively by the capacity of spring means 86-88 to yield vertically and in horizontal shear and the resistance of the spring means 86-88 to vertical and shear horizontal deflections, damping of such movements being accomplished by reasons of hysteresis in elastomeric pad devices 86.

For preventing separation of the bogie frame from the axle bearings while permitting the vertical and yaw movements accommodated by springs 87, journal bearing adapters 81 are formed with upwardly extending stems 93 which pass through slightly larger openings 95 in the bottom wall of the box section bogie frame and portions 91 and a transversely extending removable pin 97 extends through upstanding stems 93 and projects outwardly through generally rectangular vertically elongated openings 99 in the side walls of the box section end portions 91 of the bogie frame side members 27 a.

Except for the fact that resistance to yaw and longitudinal movement of the axle and damping of axle yaw movement is provided by resistance of spring means 86-88 to deflection in shear longitudinally of the bogie and by the damping characteristics of the elastomeric pads 86, operation of the bogie of Figures 5-7 is identical to that of the first embodiment, in which vertical cushioning of the bogie frame and vertical damping is provided by the vertical resiliencey of V-shaped elastomeric sandwich devices 11, 13 and resistance to yaw and longitudinal movement of the axle bearings and damping of axle yaw movemovements is provided by resistance in flat elastomeric sandwich devices 23, 25 to shear lengthwise of the bogie and the damping characteristics of the elastomeric devices.

In the embodiment of Figures 8-10, the same numerals as are used in Figures 1 7 are used, to denote identical or substantially identical elements, the principal difference between the bogies of the embodiments of Figures 1 4 and 5 7 and the embodiment of Figures 8 10 being in the primary suspension whereby the bogie frame is supported from the axles In the bogie of Figures 8 10 the housings 105 of journal bearings 106 are of cylindrical shape and are surrounded by an elastomeric grommet 107 which is clamped between semi-cylindrical apertures 109 in the vertically divided journal bearing adapter halves 111 and 112.

Journal bearing adapter halves 111 and 112 are formed at their tops with hinge pin bearing members 113 and 114 through which a hinge pin 115 extends to permit opening up the adapter 111, 112 for insertion and removal of grommets 107 and journal bearing housings 105 On their lower surfaces, adapter halves 111 and 112 are formed with depending bosses 116 and 117 with aligned holes receiving a bolt 119 by which the journal bearing adapter halves are secured to each other in abutting assembled relation by means of a nut 121 on bolt 119.

With this arrangement of the journal bearings and their housings 105, the surrounding grommets 107 and the journal bearing adapter structure 111, 112 thus described, it will be evident that the axle 2 or 3 will be capable of movement transversely of the bogie with respect to the journal bearing adapters 111 and 112 to the extent that the elastomeric material of grommet 107 is yieldable in shear.

To support the bogie frame from the journal bearing adapters 111, 112 the bogie frame end portions 120 are formed with downwardly open pedestal jaws defined by depending legs 121 and 123 spaced apart longitudinally of the bogie a substantially greater distance than the maximum dimension longitudinally of the bogie of axle bearing adapters 111, 112, and their inner surfaces 125 and 127 respectively are symmetrically inclined slightly toward each other upwardly in a direction longitudinally of the bogie and are of concave V-shape with their apices 129 pointing away from the respective axle The outer transverse surfaces 131 and 133 respectively of journal bearing adapter halves 111 and 112 are similarly inclined substantially parallel respectively to pedestal surfaces 125 and 127 and are of similar, though convex, V-shaped cross section Interposed between the opposed V-shaped surfaces 125, 131 and 127, 133 are multi-layer sandwich devices of chevron shape in plan, each consisting of three V-shaped elastomeric pads 135 interleaved by V-shaped metal plates 139 and bounded by V-shaped metal boundary plates 141 and 143 Elastomeric pads 135 are bonded to the adjacent metal plates 135, 141, and 143, and inner boundary plates 141 are secured to the outer V-shaped surfaces 5157 325 131 and 133 of the axle bearing adapter halves 111 and 112, and the outer boundary plates 143 of the elastomeric sandwich devices are secured to V-shaped surfaces 125 and 127 respectively of the pedestal legs, such that the bogie frame is supported on the axle bearing housings 111 and 112 by the resistance to shear and compression vertically of elastomeric pads 135, vertical cushioning of the bogie frame being provided by the yieldability, principally in shear vertically, of the elastomeric pads 135 The sandwich devices 135, 139, 141, 143, the mounting surfaces 131 and 133 of journal bearing adapters 111, 112 and the mounting surfaces 125 and 127 of pedestals 121 and 123 are sharply angled, preferably in the order of 90 , as compared with the corresponding obtusely-angled surfaces in the first embodiment (Figure 4), such that elastomeric pads 135 are relatively yieldable longitudinally of the bogie due to their relatively large shear component and relatively small compression component lengthwise of the bogie as compared with pads 13 of the first embodiment, thus accommodating substantial movement lengthwise of the bogie of the respective axle journal portions and eliminating the need for additional means such as sandwich devices 23, 25 of the first embodiment to accommodate such longitudinal movement of the axle ends as is required for radial movements of the axles on curved track Inasmuch as the chevron sandwich devices of this relatively acute angular configuration provide substantially greater resistance through compression transversely of the bogie than is provided by the obtusely angled chevrons of the final embodiment, movements of the axles transversely of the bogie, required for radiation of the axles on curved track and to cushion the bogie frame from impact due to transverse irregularities in the bogie rails, are accommodated by shear in elastomeric grommets 109 in a direction transverse of the bogie.

To oppose any tendencies of pedestal legs 121 and 123 to spread apart due to the longitudinal components of the load applied through chevron devices 135, 139, 141, 143, the lower ends of the pedestal legs are secured to each other by tie bolts 151.

The resultant structure is substantially simpler and less expensive than the first embodiment and is equally effective in accommodating the slight longitudinal and transverse movements of the axle bearings required for radial positioning of the axles during movement on curved track.

Preferably the diagonal links 47 and 49, if used, are pivotally connected at 45 to brackets 149 extending inwardly from the axle bearing housings 105.

It will be evident from the description of the embodiment of Figures 8 10 that when steering forces are applied to the axles as a result of the differential effect of the high conicity treads of the inner and outer wheels, the journal portions of the axles and their surrounding bearings and bearing housings 105 will be permitted to move longitudinally in the pedestal jaws by reason of the relatively sharp angular configuration of the chevron pad devices with their consequent large shear components and relatively small compression components lengthwise of the bogie and shear in grommets 109 between journal bearing housings 105 and journal bearing adapters 111, 112 will permit the necessary movement of the axles transverse of the bogie, compensating for the trasverse stiffness of the chevron devices resulting from their relatively high compression component transversely of the bogie Impacts received by the wheel and axle assemblies from transverse irregularities in the bogie rails are absorbed by shear in grommets 107 which thereby cushion the bogies frame from such impacts.

Claims (4)

WHAT WE CLAIM IS:-

1 A railway bogie comprising a pair of wheel and axle assemblies each having a pair of railway flanged wheels rigidly mounted on the ends of the axle, a bogie frame supported from said wheel and axle assemblies and accommodating relative turning movements of said wheel and axle assemblies in the horizontal plane for steering, said wheel and axle assemblies having steering means causing them to pivot in opposite senses on curved track, a brake system comprising brake shoes engageable with the respective wheel treads, means swingably supporting each brake shoe from said bogie frame, an extensible rod device connecting the brake shoes at each side of the bogie frame for causing them to be separated longitudinally of the bogie and forced into braking engagement with the respective wheel treads, each said extensible rod device comprising a longitudinally extending cylinder and piston assembly connected at its respective ends to said brake shoes, and a hydraulic fluid interconnection between said cylinders at opposite sides of the bogie, whereby to positively equalize braking pressure on the separate brake shoes on both sides, irrespective of differences in the longitudinal spacing of the wheels on the opposite sides of the bogie resulting from steering action of said wheel and axle assemblies.

2 A railway bogie as claimed in claim 1, wherein each brake shoe supporting means comprises an upright lever pivotally supported on said bogie frame at its upper end, the respective brake shoe and extensible rod device being pivotally connected to said lever below the pivotal connecton of said 1 573 326 1 573 326 lever to said bogie frame.

3 A railway bogie as claimed in claim 2, wherein each brake shoe is connected to its respective lever intermediate the ends of said lever and the respective extensible rod device is connected to said lever adjacent the lower end thereof.

4 A railway bogie as claimed in claim 2 or 3, wherein each brake shoe is fixedly secured to a respective brake head, and each brake head is pivotally mounted directly on the respective lever.

BOULT, WADE & TENNANT, 34, Cursitor Street, London, EC 4 A 1 PQ.

Chartered Patent Agents.

Printed for Her Majesty's Stationery Office.

by Croydon Printing Company Limited, Croydon, Surrey, 1980.

Published by The Patent Office 25 Southampton Buildings, London WC 2 A LAY, from which copies may be obtained.

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