GB2600772A

GB2600772A - Improved registration arm

Info

Publication number: GB2600772A
Application number: GB2017737.4A
Authority: GB
Inventors: Reddall Ian; Andrew Walker Gary
Original assignee: Hastec Rail Ltd
Current assignee: Hastec Rail Ltd
Priority date: 2020-11-10
Filing date: 2020-11-10
Publication date: 2022-05-11
Anticipated expiration: 2040-11-10
Also published as: GB2600772B; GB202017737D0

Abstract

A registration arm connector for connecting a registration arm 600 to a support structure of an overhead line equipment comprises an elongate beam (601) having a first end and a second end and a connector. The connector comprises a bracket which mounts to a support structure, the mounting bracket having a plate or tang which contains a swivel joint or rose joint or heim joint 1010, a U-shaped connector 605, a clevis pin or connecting pin 1150 and retaining pin 1151. The connector may allow a arc of movement plus or minus 15 degrees either side of a straight ahead position. The clevis arrangement may be reversed such that the tang portion of the joint is mounted on the registration arm and the clevis bracket is fitted on the mounting bracket. Also disclosed are methods of refurbishing a known registration arm by fitting a plate or clevis bracket to a first end.

Description

IMPROVED REGISTRATION ARM

Field of the Invention

[0001] The present invention relates to a registration arm for an overhead electric railway line.

Background of the Invention

[0002] Electric trains are now preferred over traditional diesel trains due to numerous operational and environmental benefits. There are several known methods for powering electric trains, including overhead line equipment, and an electric rail which lies between the two parallel rails of a railway track, or high energy stored in batteries carried on board a locomotive or in another wagon or carriage of a train.

[0003] In railway overhead line installations, one or more overhead power lines are suspended above a track from a plurality of gantries or posts. Electric railways use either an electric locomotive which pushes or pulls carriages which do not have their own motive power, or electric multiple units, which are passenger carriages which have their own on-board electric motors. A train locomotive or electric carriage is provided with a set of pantographs which extend upwardly above the roof of the locomotive or carriage and which make moving electrical current connection with an overhead electric line as the train proceeds along the track. Electrical power is conducted down a conductor on the pantograph, fed into an electrical system within the locomotive or carriage which powers one or more electric motors which provide motive force to drive the locomotive or electric carriage along the railway track.

[0004] Overhead line equipment (OLE) is currently the favoured power supply for electric trains. Overhead line equipment refers to the assembly of overhead wires and their supporting infrastructure which may carry electricity at high voltages, typically up to 25,000 volts, which is used to power electric trains.

[0005] Referring to Figures 1 and 2 herein, there is illustrated schematically one example of a known overhead line equipment 100, comprising an assembly of wires positioned over a rail track by a supporting infrastructure. The overhead line equipment 100 comprises a mast 101 located at one side of the track; a laterally extending arm 102 which extends over a track 103 along which a train may travel; the arm 102 having an electric insulator 104 which electrically isolates an overhead line or contact wire 105 from the supporting structure, in this case mast 101; a cantilever arm 106 which holds a catenary line 107; a pull off arm 108 which is suspended from the catenary line 107; and a registration arm 109 which is attached to a lower end of the pull of arm. The catenary line 107, cantilever arm 106, pull off arm, registration arm 109 and contact wire 105 are all electrically live at high voltage and insulated from the mast structure by the insulator 104.

[0006] The laterally extending overhead arm 102 in this example has a triangular truss shaped structure, which is attached to mast 101 by a swivel fastening 110, which allows the arm to swing over a limited range of movement to accommodate expansion or contraction, or wind loading of the overhead line or wire 105.

[0007] An auto transformer feed 111 is supported from an upper arm 112 by a second insulator 113. An earth wire 114 connects successive masts along the railway line, to ensure that the masts do not become electrically live.

[0008] Referring to Figure 2 herein, along a length of the track, a plurality of such masts or gantries are provided to suspend a continuous overhead electrical line or wire over the track.

[0009] Electricity is supplied to the overhead line equipment by a feeder substation. The overhead wire 105 carrying the electric current is also referred to as the contact wire. Attached to the roof of each electric train is a pantograph, this glides along the contact wire of the overhead line equipment transmitting the power from the overhead line equipment to the train. It is important to ensure that there is constant contact between the contact wire and the pantograph, otherwise the energy supply to the electric train will be intermittently cut off leading to loss of motive power to the train. The current flows from the pantograph to the motor in the train and then to the train wheels where it is the sent back through the rails to the feeder substation to complete the electric circuit. A complete circuit is needed for the current to flow and for the electric train to run.

[0010] In variations of the known overhead line equipment, the mast may be replaced by a gantry having upright posts on either side of the track, or the 10 contact wire or line may be suspended from a sub assembly fixed to the roof of a tunnel, without the use of a mast or gantry.

[0011] Referring to Figure 3 herein, for multiple rail tracks side by side, the masts may be replaced by portals. Where there are more than two tracks, cantilever masts are not always feasible. Instead, a steel frame 300 may be adopted spanning multiple tracks. This is generally referred to as a portal frame. The frame consists of a pair of opposing masts 301, 302 joined by a horizontal boom 303, which might be H section or lattice steel as shown in Figure 3 herein. On the frames, the cantilevers 304 supporting the wires are attached to the boom by vertical members 305 called drop tubes. The registration arm 306, which carries the live overhead wire 307, is still hung off a pull off arm or "goose neck" 308 as with the mast arrangement. An earth wire 309 connects successive frames together, and an auto-transformer feed 310 runs parallel to the tracks suspended from the frame.

[0012] The design and specification of the overhead line equipment is carefully calculated and maintained to ensure constant contact between the contact wire and the pantograph attached to roof of the train. Multiple parameters effect the dimensions of the overhead line equipment. In order to keep the contact wire positioned within the required geometry it is supported by a second wire known as the catenary wire 107, 311. The catenary wire 107, 311 is attached to the contact wire 105, 307 at intervals by a registration arm 109, 306, the registration arms are pointed at various angles to direct the contact wire in a particular path. The registration arm is electrically live. The vertical movement of the pantograph is accommodated by a vertical movement of the ends of the registration arms to which the overhead lines are attached. The contact wire is staggered, following a zig-zag path from side to side so as to achieve an even wear across the pantograph of the electric train.

[0013] Referring to Figure 4 herein, there is illustrated schematically a known registration arm 400 suspended at one end by a drop beam 401 which is secured to a cantilever arm.

[0014] The known registration arm 400 comprises an elongate beam having a first substantially straight portion 402, a second substantially straight portion 403, and a curved portion 404 between the first and second substantially straight portions. At a first end of the known registration arm (sometimes called a heel), there is provided a hook portion 405 for hooking over an eye or loop 406 fitted to the pull off arm or, as shown in Figure 4 to a drop link 401, to connect the first end of the registration arm to the pull off arm or drop link in a manner which accommodates both up and down movement and swing or lateral movement (along the track direction movement) of the second end of the registration arm relative to the first end of the registration arm. At the second end of the registration arm there is provided a suspension connector 407 for suspending a live electrical contact wire 408 to the second end of the registration arm.

[0015] Other forms of known registration arm have an elongate curved arm of a different curvature shape, such as an over reach registration arm which reaches or spans over an intermediate wire between the first and second ends of the registration arm. These registration arms are also supported at their first end or heel end to a support by a hook on the heel of the registration arm, which fits into an eye or loop on the supporting structure.

[0016] Referring to Figure 5 herein, there is illustrated schematically a known mounting bracket 500 which fits to an upright support structure, for mounting a heel end of a registration arm to a pull off arm or to a drop link. The known mounting bracket comprises a back plate 501, having a curved channel shape to accommodate the outer surface of a support structure such as a drop link 401; a torus loop 406 forming an eye and extending from the back plate; and a U bolt 502 which extends around the support member and which is secured to the back plate by a pair of nuts which extend through first and second apertures in the back plate [0017] Yet further registration arm types have space frame structure beams which may be either straight, "V" shaped, or curved.

[0018] Each known registration arm is connected to its supporting structure, such as a pull off arm or drop bar or beam, by a hook and eye arrangement with the hook being provided either on the end of the registration arm so the end of the arm is hooked over an eye loop support mounted to the support structure, or alternatively a hook is mounted on the support structure, and a loop or eye is provided on the end of the registration arm. The registration arm and hook arrangement is not intended to support the contact wire, but is intended to pull the contact wire into its correct position so as to achieve the correct degree of lateral stagger of the contact wire.

[0019] The contact wire, catenary support and registration arm are subject to a number of mechanical loads. These include: Permanent vertical loads -the dead loads caused by the weight of the overhead line equipment; Ice vertical loads -loads created by the weight of ice forming on the catenary wire and contact wire under cold weather conditions; Permanent radial loads -dead loads caused by a component of the wire tension being transferred to a structure when the contact wire changes direction due to stagger; VVind radial loads -live radial loads created by the action of wind on the contact wire; Line direction loads -loads which pull the end of the registration arm along the direction of the track due to expansion or contraction of the contact wire, or due to tensioning weights used to tension the contact wire, or due to drag of the pantograph on the contact wire.

[0020] The support structure and registration arm components must be capable of withstanding all of these loads in combination. In particular, the permanent and wind loads affect the operation of the support and registration arm assemblies since registration arms behave poorly if not held in tension.

[0021] The hook and loop arrangement for connecting the registration arm to the support structure is a metal on metal connection with no other mechanical fixings, but just a hook which fits into a loop or eye mount.

[0022] A problem with the known hook and eye arrangement for mounting the known registration arm to a support structure, where the hook is provided on the end of the registration arm, is that if there is little or no tension on the wire the registration arm will "chatter" at the drop arm or pull off arm bracket fitting at the heel of the registration arm and electrical arcing may occur across the bracket fitting, eventually causing failure of the fitting. The hook moves around within the eye or loop due to wind or other loadings on the contact wire. As the registration arm is live carrying high-voltage typically up to 25,000 V, sparking occurs at the connection between the end of the registration arm and the pull off arm as the hook part moves within the aperture in the eye mounting. Sparking causes spark erosion and micro-welds of the hook end of the registration arm, reducing the strength and reliability of the hook, and ultimately if not replaced, leads to failure of the hook. At the other extreme, too much radial load can also lead to failure of the registration arm fitting. If the heel end of the registration arm fails, it will become detached from the support structure, and the contact wire and the registration arm will hang down and train driving into the damaged registration arm experiences damage to its pantograph.

[0023] In the United Kingdom, there are tens of thousands of registration arms in use, and worldwide there are millions of registration arms using the known hook and eye mounting method. Regular and routine inspection of registration arms is needed so that preventative maintenance can be carried out in good time before encountering registration arm failure. Further, the known registration arms require regular lubrication of the hook and loop / hook and eye connections, which means downtime for the railway line whilst the lubrication of the registration arm ends takes place.

Summary of the Invention

[0024] According to a first aspect there of the present invention, there is provided a registration arm connector for connecting a registration arm to a support structure of an overhead line equipment, said registration arm comprising: an elongate beam having a first end and a second end; said connector comprising: a bracket comprising first and second spaced apart plates, said first plate having a first aperture and said second plate having a second aperture; a first ring having a convex part spherical outer surface; said first ring having an aperture therein; a second ring having a concave part spherical surface; wherein said first ring engages said second ring such that said convex part spherical surface of said first ring engages said concave part spherical surface of said second ring, and a pin for engaging through said apertures of said first and second spaced apart plates and through said aperture in said first ring.

[0025] Preferably the connector further comprising a tang having an aperture there through, wherein said second ring locates within said aperture of said tang.

[0026] Preferably, a range of movement between a main plane bisecting said tang and lying perpendicular to said aperture through said tang and a main plane which bisects said bracket and lies equidistantly between said first and second side plates of said bracket, is in the range 0-300.

[0027] A fit between an outer surface of said outer ring and an inner surface of said aperture of said tang may be an interference fit.

[0028] A fit between an outer surface said second ring and an inner surface of said aperture through said tang may be is a clearance fit.

[0029] Preferably an outer diameter of said convex part spherical surface of said first ring is a clearance fit to said concave part spherical surface of said second ring.

[0030] Preferably said first ring comprises a part spherical body having: a part spherical convex outer surface; a first substantially flat face; a second substantially flat face, wherein said first and second substantially flat faces lie diametrically opposed to each other on opposite sides of said part spherical body; and a circular cylindrical aperture extending through said body between said first and second substantially flat faces.

[0031] Preferably the said inner ring comprises stainless steel.

[0032] Preferably said concave part-spherical surface of said second ring comprises a low friction coefficient material.

[0033] The low friction coefficient material may comprise a material selected from the set: a plastics material; Teflon®; bronze.

[0034] When the first ring does not have a connector pin through the central aperture of the first ring, the first ring may rotate with respect to said second ring throughout a full 3600 rotation in any plane.

[0035] According to a second aspect there is provided a registration arm for an overhead line equipment, said registration arm comprising: an elongate beam having a first end and a second end, and a beam portion extending between said first and second ends; a plate having a circular cylindrical aperture there through; said plate extending such that a main plane bisecting said plate, and lying parallel to first and second planes which coincide respectively with first and second main outer surfaces either side of said plate, lies parallel to a main plane which bisects the whole of said beam portion, including said first and second beam ends.

[0036] According to a third aspect there is provided an end connector for a registration arm, for connecting an end of a registration arm to a supporting structure, said end connector comprising a bracket, a rotatable joint, and a pin; said bracket comprising: a base plate; a first side plate extending from a first side of said base plate, said first side plate comprising a first aperture; a second side plate extending from a second side of said base plate, said second side plate comprising a second aperture, said first and second side plates facing opposite each other such that said first and second apertures lie opposite and in line with each other; said rotatable joint comprising an outer ring and an inner ring; said outer ring comprising an annular outer surface and a concave part spherical inner surface, said inner ring comprising a part spherical outer surface and a circular cylindrical aperture; wherein said inner ring locates in said outer ring such that said inner ring is rotationally moveable with respect to said outer ring; and wherein said pin engages through said first and second apertures of said first and second side plates, and through said aperture of said inner ring to locate said inner and outer rings between said first and second side plates, and to retain said inner and outer rings to said bracket; and a third plate having an aperture therethrough, said third plate moveably locating between said first and second plates, wherein said outer ring locates in said aperture of said third plate, such that said third plate retains to said bracket by said inner and outer rings, and by said pin.

[0037] According to a fourth aspect there is provided a mounting bracket for mounting to an upright support structure of an overhead line equipment for railway, said mounting bracket comprising: a back plate having an indented rear surface to fit around a portion of a said support structure; an extending tang portion comprising a flat plate, said tang portion extending outwardly from said back plate; said tang portion comprising a circular cylindrical inner surface surrounding an aperture through said tang portion.

[0038] Preferably said back plate comprises a channel for shaped for fitting to an upright surface of the support structure; and a main geometric central axis of said aperture lies across a main length direction of said channel.

[0039] Preferably said tang comprises a plate having first and second upright sides, said aperture extending between said first and second upright sides.

[0040] Preferably said plate comprises a part toroidal loop extending around said aperture.

[0041] Preferably said back plate comprises first and second spaced apart apertures; wherein said tang plate is located between said first and second spaced apart apertures.

[0042] Preferably wherein said back plate comprises first and second spaced apart apertures; wherein said tang plate is located between said first and second spaced apart apertures.

[0043] According to a fifth aspect there is provided a method of refurbishing a known registration arm for an overhead electrical line, for connecting to a support structure of said overhead line equipment, said method comprising: fitting a first plate to a first end of said registration arm, said first plate having a substantially circular cylindrical aperture which has a main geometric central axis which lies across a pair of planes coinciding with the sides of said first plate.

[0044] The method may further comprise cutting a hook or a loop off said first end of said registration arm prior to fixing said first plate to said first end of said registration arm; and welding a bracket to said first end of said registration arm, said bracket comprising said first plate.

[0045] According to a sixth aspect there is provided a method of refurbishing a known registration arm for an overhead electrical line, and connecting said refurbished registration arm to a support structure of said overhead line equipment, said method comprising: fitting a first plate to a first end of said registration arm, said first plate having a substantially circular cylindrical aperture which has a main geometric central axis which lies across a pair of planes coinciding with upright sides of said first plate; securing a second plate to said support structure, said second plate having an aperture there through, said aperture extending between first and second sides of said second plate; securing said first plate to said second plate by means of a swivel joint having an inner part which has an outwardly facing part spherical bearing surface, and an outer part which has an inwardly facing part spherical bearing surface, wherein the outwardly facing and inwardly facing part spherical bearing surfaces are in direct contact with each other; and securing the first plate to the swivel joint by passing a connector pin through an aperture in said first plate and through an aperture in said inner part of said joint.

[0046] The method of refurbishing a known registration arm for an overhead electrical line, and connecting said refurbished registration arm to a support structure may further comprise: passing said connector pin through an aperture in said first plate; and passing said connector pin through an aperture in a further plate which lies on an opposite side of said swivel joint to said first plate.

[0047] Other aspects are as set out in the claims herein, which forms part of the specific disclosure of this specification.

Brief Description of the Drawings

[0048] For a better understanding of the invention and to show how the same may be carried into effect, there will now be described by way of example only, specific embodiments, methods and processes according to the present invention with reference to the accompanying drawings in which: Figure 1 herein shows schematically a known overhead line equipment mast, with known overhead line equipment components for an electric railway; Figure 2 herein shows schematically a view of a plurality of known masts for supporting an overhead line, and showing side to side stagger of the contact wire along the length of the track; Figure 3 herein shows schematically a known overhead portal or gantry, carrying a plurality of overhead electric lines above a plurality of railway tracks, each overhead wire being supported by a drop tube, a cantilever bar, a pull off arm, and a registration arm; Figure 4 herein shows schematically one example of a known registration arm for an overhead wire, having one end supported on a supporting drop beam by a hook and eye arrangement to a mounting bracket which attaches to the drop beam; Figure 5 herein shows schematically an example of a known hook bracket which attaches to an upright beam or drop bar for supporting an end of a registration arm to the upright beam or drop bar; Figure 6 herein shows schematically a novel registration arm supported on a known drop bar by a novel mounting assembly according to a first specific embodiment disclosed herein; Figure 7 shows schematically the registration arm and mounting assembly of Figure 6 herein in view from above; Figure 8 shows schematically the registration arm of Figure 6 with partial cutaway view of the connection between a first end of the registration arm and a mounting bracket, and with partial cutaway view at a second end of the arm, which carries the contact wire; Figure 9 herein shows schematically another view of the registration arm for an overhead line equipment according to the first specific embodiment of the invention; Figure 10 herein shows schematically connection of the registration arm of Figure 6 to a support structure, such as a drop bar or a pull off arm; Figure 11 herein shows schematically in plan view, a clevis and tang type connector for attaching between the registration arm of Figure 6 herein, and a support bracket supporting one end of the registration arm on a support structure; Figure 12 herein shows schematically in view from above a range of lateral movement of the registration arm of Figure 6 herein, when mounted to an upright support structure using the novel connector of Figure 11 herein; Figure 13 herein shows schematically the registration arm and novel connector of Figures 6 to 12 herein in view from one side in a substantially level position; Figure 14 herein shows schematically the registration the arm of Figures 6 to 12 herein in view from one side in a raised position; Figure 15 herein shows schematically the registration arm of Figures 6 to 12 herein in view from one side in a lowered position.

Details Description of the Embodiments

[0049] There will now be described by way of example a specific mode contemplated by the inventors. In the following description numerous specific details are set forth in order to provide a thorough understanding. It will be apparent however, to one skilled in the art, that the present invention may be practiced without limitation to these specific details. In other instances, well known methods and structures have not been described in detail so as not to unnecessarily obscure the description.

1 0 [0050] In the following description, across the accompanying Figures, like parts are denoted by like reference numbers.

[0051] In this specification, the term clevis pin is used to refer to a connecting pin which is used for example, in a joint assembly to movably connect a clevis bracket to a tang through an aperture in the tang and through a pair of apertures in opposing plates of the clevis bracket.

[0052] In this specification the term clevis bracket is used to mean a pair of spaced apart opposing plates, each having a respective aperture, wherein the apertures of the opposing plates lie on a common central axis which passes substantially centrally through each of the apertures.

[0053] Referring to Figure 6 herein there is shown schematically in side view a novel registration arm 600 according to a first specific embodiment disclosed herein. The first registration arm comprises a main beam 601 comprising a first substantially straight portion 602; a second substantially straight portion 603; and a curved portion 604 located between the first and second substantially straight portions; an end connector 605 at a first or proximal end (or heel end) of the beam, for connecting the first end of the registration arm to a supporting structure, such as a pull off arm; and a wire suspension connector 606 at a second or distal end of the main beam, at an end of the second substantially straight portion.

[0054] There is provided a mounting bracket 607 which fits to a support structure 608, which mounts the registration arm to the support structure. The mounting bracket comprises a flat plate or tang having an aperture there through forming a loop, and into which is fitted a movable swivel joint having a part spherical bearing, through which a pin may be slid to attach the first end of the registration arm to the mounting bracket, and thereby mount the first end of the registration arm to the upright support member 608. The first end of the registration arm carries a clevis type bracket, and is connected to the mounting bracket 607 by a clevis pin or connecting pin 610 which fits into the spherical or swivel bearing. The spherical bearing comprises part of a rose joint or heim joint fitted into the aperture in a tang of the mounting bracket.

[0055] At the first end of the registration arm, there is provided a clevis type substantially "U" shaped bracket having a first lateral plate having a first circular cylindrical aperture, a second lateral plate which lies substantially parallel to the first lateral plate, and which has a second circular cylindrical aperture, wherein the first and second plates lie opposite and substantially parallel to each other, being spaced apart across a void there -between, so that the first and second apertures lie opposite each other and line up with each other such that a common main geometric central axis passes centrally through each of the first and second apertures. The first and second plates are held rigidly spaced apart from each other by an end plate, to which a respective one end of each of the first and second plates are attached.

[0056] Each of the first and second side plates has an inner surface which is circular cylindrical in form, so that the circular cylindrical pin fits closely through both apertures in use.

[0057] In a preferred embodiment, the whole registration arm is made of 6082 -T6 aluminium for lightness and low cost.

[0058] Referring to Figure 7 herein, there is illustrated schematically the registration arm and connector as viewed from above. In this view, the registration arm extends with its main length perpendicular to the underlying track, with no long-track movement of the registration arm being encountered.

[0059] Referring to Figure 8 herein, there is illustrated schematically the registration arm and connector as viewed from one side. In this example, the registration is in a substantially level or neutral position.

1 0 [0060] Referring to Figure 9 herein, there is illustrated schematically a view from one side of the mounting bracket, showing the registration arm swung about the connecting joint which connects the first end of the registration arm to the mounting bracket. In the view shown, the registration arm is swung at an angle from its nominal installation position where the main length of the registration arm is at 900 to the main length of the underlying track, and the main length direction of the registration arm is at an angle of around 15° to a main plane which bisects the tang of the mounting bracket, this being the maximum extent of swing allowed in the lateral along-track direction, and limited by the geometry of the swivel or rose joint which connects the end of the registration arm to the mounting bracket.

[0061] Referring to Figure 10 herein, there is shown in greater detail the connection between the first end of the registration arm and the support bracket 607 which is mounted to the support structure 608.

[0062] The connection comprises a mounting bracket which mounts to a support structure; the mounting bracket having a plate or tang which contains a swivel joint or rose joint 1010; a substantially U shaped connector 605, a clevis pin or connecting pin 1150 which passes through the U shaped connector and through a centre of the rose joint; and a retaining pin 1151 which fits through one end of the clevis pin to prevent the clevis pin coming loose and falling out of the end connector 605. There are also a pair of spacer rings 1160, 1161, which locate between the plates of the clevis bracket around the clevis pin between the rose joint and the clevis spin on the inside of the end connector; and an outer washer 1170 which fits on the outside of the end connector 605 between the retaining pin 1151 and the side of the end connector.

[0063] The mounting bracket comprises a back plate 1000 having an indented or channeled rear surface to fit around a cylindrical drop pole; and an extending tang portion 1001 comprising a flat plate extending in a substantially vertical plane in use, the tang plate having an aperture surrounded by a circular cylindrical inner surface 1002, there being a loop of material surrounding the aperture. The back plate 1000 of the mounting bracket comprises first and second spaced apart apertures, through which the ends of a screw threaded "U" bolt may be inserted to protrude on a front face of the back plate so that a pair of nuts 1003 can be tightened onto the protruding U bolt to secure the mounting bracket to the upright post of the support structure.

[0064] In use, the tang extends laterally or substantially horizontally. The extending tang has first and second outer side surfaces each extending in its own plane, the first and second outer side surfaces being spaced apart from each other and parallel to each other. The circular cylindrical surface extends in a direction perpendicular to the planes in which the outer side surfaces lie, a main geometric central axis of the circular cylindrical surface also lying perpendicular to the planes occupied by the sides of the laterally extending tang. The perimeter of the tang plate bounded by the upper and lower surfaces of the tang plate and the first and second ends of the tang plate is of dimensions greater than the diameter of the circular cylindrical aperture through the tang plate.

[0065] A rose joint (also called a heim joint) 1010 inserts into the cylindrical aperture in the tang. The rose joint comprises an outer ring 1011 and an inner ring 1012, where the inner ring fits inside the outer ring. The outer ring has a circular cylindrical outer surface; a first flat annular face; a second flat annular face, and an inner concave spherical surface between the outer cylindrical surface, and first and second flat annular faces.

[0066] The inner ring 1011 comprises a body having a convex outer spherical surface; a first flat annular face; a second flat annular face; and a circular cylindrical inner face surrounding an aperture or passage through the centre of the inner ring. The spherical outer surface and the circular cylindrical inner surface extend between the first and second annular faces.

[0067] The second or outer ring 1012 comprises an outer ring body having concave part spherical inner surface; a circular cylindrical outer surface; a first flat annular face; a second flat annular face; the concave part spherical inner surface and the circular cylindrical outer surface extending between the first and second flat annular faces, such that the concave part spherical inner surface describes an aperture or chamber through the outer ring body.

[0068] The inner ring 1011 fits inside the concave surface aperture or chamber formed within the outer ring, so that the inner ring is movable rotationally in any orientation within the aperture or chamber formed within the outer ring, and due to the part spherical concave surface of the outer ring and the part spherical convex surface of the inner ring, the inner ring is self -retaining in the chamber of the outer ring, which ever orientation the body of the inner ring adopts with respect to the body of the outer ring. The inner ring 1011 is movable with respect to the outer ring 1012 about all axes of rotation and can swivel in any direction about a nominal centre point of a sphere.

[0069] Preferably the inner ring is made of chrome plated 304 stainless steel. The part spherical convex surface of the inner ring bears against a concave part spherical inner surface of the outer ring. Preferably the concave inner surface of the outer ring is made of bronze. The outer ring may be fully bronze, or may be of stainless steel, or other suitable metal, with a bronze liner, so the at the concave inner part spherical bearing surface is of bronze. This maintains close physical contact over a part spherical area between the inner ring and outer ring of the rose joint. As there is metal to metal contact over a relatively large part spherical area, and the inner ring closely fits in to the outer ring, the incidence of electrical arcing and sparking between the end of the registration arm and the mounting bracket to the support structure is reduced.

[0070] Where the pin is not connected through the inner ring, the inner ring may rotate within a full 3600 range of movement in any direction (X, Y, or Z plane) within the outer ring about a centre point of a sphere. When the central pin is inserted through the centre of the inner ring, the range of motion of the inner ring within the outer ring is restricted by the general geometry of the tang, bracket and spherical surface joint, with the pin contacting the perimeter of the aperture through the outer ring, and/or by the ends of the sides of the clevis bracket contacting the tang. The outer ring of the joint may have a circular cylindrical outer surface of dimensions to make an interference fit or a force fit into the corresponding aperture through the tang of the mounting bracket.

[0071] At a first end of the registration arm, there is provided a substantially "U" shaped clevis end connector 605, formed from a first end connector side plate 1120, a second end connector side plate 1121, the first and second end connector side plates being parallel to each other and spaced apart from each other and facing opposite each other; each end connector plate having a circular cylindrical aperture there through, the apertures lying opposite each other such that the inner surface surrounding each aperture lies upon a common circular cylindrical surface.

[0072] Referring to Figure 11 herein, there is illustrated schematically in plan view, the joint between the mounting bracket and the end of the registration arm. The joint comprises clevis bracket 605 which comprises end plate 1122 which is bisected by and parallel to a plane which extends perpendicular to a main plane which bisects and is parallel to a main length axis of the remainder of the registration arm; first end connector side plate 1120, second end connector side plate 1121, the first and second end connector side plates being parallel to each other and spaced apart from each other and facing opposite each other across a gap in which the tang 1001 of the mounting bracket fits. The tang fits in the gap between the opposing plates of the clevis bracket. The thickness dimension of the mounting bracket tang 1001 is such that the tang as able to pivot about the clevis pin 1150 in the space between the opposing sides of the clevis bracket, allowing the clevis bracket to swing over an arc of movement plus or minus around 15° either side of a straight ahead or in line nominal rest position where the main plane bisecting the tang and parallel to the sides of the tang lines up and coincides with the main upright plane which bisects the registration arm and which lies parallel to the main length direction of the registration arm.

[0073] In the embodiment shown, the clevis pin 1150 comprises a circular cylindrical bar having a smooth outer surface, and at one end a hexagon shaped head having a diameter greater than the diameter of the smooth outer surface, and greater than the diameter of the apertures through each of the side plates, to retain the pin in the apertures in the pair of side plates by limiting the travel of the pin in the axial direction. At the other end of the clevis pin there is provided a passage through which a split pin 1151, cotter pin 1151 or the like may be inserted to retain the other end of the pin in the clevis bracket and prevent the pin from sliding out of the bracket.

[0074] The retaining pin 1151 may comprise a split pin, a spring clip, cotter pin or the like, the purpose of which is to prevent the cylindrical clevis pin sliding out from the circular apertures in the first and second clevis side plates and the centre aperture through the inner ring of the rose joint.

[0075] Preferably, a main geometric central axis of the aperture of the registration arm through which the clevis pin fits, lies across a pair of planes which lie either side of the registration arm and which lie parallel to a main length direction of the registration arm.

[0076] When fitted to a support structure, the eye in the mounting bracket fitted to the support structure has its main geometric central axis substantially horizontal, so that as viewed from one end, the eye forms a circle in an upright plane.

[0077] In use, where the drop link for the supporting member is substantially vertical, the main central axis of the aperture in the mounting bracket tang lies substantially horizontally.

[0078] Referring to Figure 12 herein, there is illustrated schematically in view from above, the registration arm of Figures 6 to 11 herein, showing a range of lateral movement pivoting around the connection point between the end of the registration arm and the centre point of the aperture through the tang of the support bracket.

[0079] The movement permitted by the spherical surface joint permits the 15 end of the registration arm to move in an arc to accommodate movement of the catenary wire in either direction along the underlying railway track.

[0080] The registration arm pivots around a nominally horizontal main central axis of the clevis pin passing through the spherical joint and through the tang of the support bracket allowing both lateral swing, and vertical movement so that the tip of the registration arm may describe a segment of a spherical area, where the tip of the registration arm can range over any position on the segment of the spherical area.

[0081] In the example shown, a maximum lateral range of movement of a vertical plane passing through a centre line of the registration arm has a range of movement of + or -15° either side of a nominal rest position where a main length direction of the registration arm is perpendicular to the underlying railway line, so that the arm can swing over a lateral or horizontal range of 30°. For the length of registration arm as shown, the distance of movement of the second end of the registration at a point which supports the catenary wire may move a maximum of 28.8 cm in either direction, giving a maximum range of movement of the drop hangar at the end of the registration onto which the contemporary wire attaches of around 58 cm either side of the nominal neutral central rest position of the registration arm.

[0082] The maximum lateral angle of movement of the registration arm with respect to the is main upright plane passing centrally through the tang is restricted in the embodiment of Figures 6 to 11 by the geometry of the clevis bracket and the tang, in particular, by the spacing between the side plates of the clevis bracket and the length by which the side plates project beyond the perimeters of the apertures in the side plates of the clevis bracket. In the embodiment shown the maximum range of lateral movement, as shown in Figure 11 herein is 150 either side of a main plane which bisects the tang and which lies perpendicular to a circular cylindrical surface defining the opposing apertures which line up with each other and pass through the first and second side plates, giving a full lateral range of movement of the registration arm of 300 side to side. This accommodates movement of the catenary wire in either direction along a main length of the railway track.

[0083] Figure 13 herein shows schematically the registration arm and novel connector of Figures 6 to 12 herein in view from one side in a substantially level position. In the level position, the contact wire connector 606 is at substantially the same horizontal level as the horizontal axis of the connector pin which connects the first end of the registration arm to the support mounting bracket via the spherical swivel joint.

[0084] Figure 14 herein shows schematically the registration the arm of Figures 6 to 12 herein in view from one side in a raised position. In the raised position, the second end of the registration arm which carries the contact wire connector 606 is raised at an angle of up to 45° from horizontal, and the portion of the arm nearest the first end is raised at an angle of up to 70° to the horizontal.

[0085] Figure 15 herein shows schematically the registration arm of Figures 6 to 12 herein in view from one side in a lowered position in which the second end of the registration arm which carries the contact wire connector 606 is lowered at an angle of up to 300 with respect to the horizontal, about the central axis of the connector pin through the swivel joint.

[0086] The angular range of motion of the tip of the second end of the registration arm with respect to the pivot point about the centre of the swivel joint may be in the range 45° upwards above horizontal and -300 downwards below 1 0 horizontal. At the same time, the horizontal range of movement of the tip of the second end of the registration arm, which carries the contact wire connector point 606 may be in the range + or -15° from a nominal rest position in which the main length of the registration arm lies across the rails substantially perpendicular to the next rails, so that the tip of the second end of the registration arm has a curved surface of movement extending in a range 70° in the up / down direction relative to the central axis point of the connector pin, and a range of movement of 30° either side of a plain which is perpendicular to an upright plane which bisects the tang on the support mounting bracket.

Alternative embodiments [0087] It will be appreciated by the skilled person that in alternative embodiments, the clevis arrangement may be reversed such that the tang portion of the joint is mounted on the registration arm and the clevis bracket is fitted on the mounting bracket, and the above description, and ranges of movement of the registration arm about the connecting pin, and relative to the track and support structure apply mutatis mutandis as described above.

[0088] The joint assembly comprising a clevis bracket and/ or a tang, a rose or spherical swivel joint, and a connecting pin and may be provided as a conversion kit to retro fit to an existing known registration arm as an upgrade or to extend the operational life of a known registration arm having a hook or eye connector at its proximal end where it is mounted to a support structure.

Depending on the existing known arrangement the kit may take the following forms: [0089] A first conversion kit comprises a clevis bracket comprising first and second opposing spaced apart side plates, each having an aperture there-through, said apertures being in alignment with each other to accept a circular cylindrical pin, the bracket having a base plate extending transversely to the main central planes bisecting each of the first and second side plates, and rigidly connecting the first and second side plates together; and a joint substantially as described hereinabove, having an inner ring and an outer ring, the inner ring having a part spherical outer surface and the inner rings having an aperture bounded by a corresponding part spherical inwardly facing surface, such that the outwardly presenting outer part spherical surface of the inner ring fits closely within the inwardly facing part spherical surface of the outer ring, thereby occupying the aperture through the outer ring; the convex part spherical surface of the inner ring bearing against the concave part spherical inwardly facing surface of the outer ring; the inner ring having a circular cylindrical aperture therethrough; and a pin having a circular cylindrical main body, which closely fits through the first and second apertures of the respective first and second side plates, and the central aperture through the inner ring, the pin having a first end of increased dimension relative to the outside diameter of the main body, and a retaining clip which retains the pin in the clevis bracket without falling out.

[0090] The kit may optionally further comprise a mounting bracket, for example as shown in Figure 10 herein, for fitment to an upright support column of an overhead line equipment, the mounting bracket comprising a back plate having retaining means for retaining the bracket to a support structure, such as an upright beam or a drop rod; the retaining means may comprise a "U" bolt and one or more self -locking nuts as shown in Figure 10 herein; and extending laterally from the back plate, an elongate tang member, preferably in the form of a plate of metal having a circular cylindrical aperture there through, the aperture having a main central geometric axis extending in a direction parallel to a main plane extending perpendicular to a main plane which bisects and is parallel to one or each major outer surface of the tang plate; such that in use the main geometric axis of the aperture through the tang lies substantially perpendicular to the upright support structure to which the mounting bracket is intended to be attached.

[0091] The outer ring of the joint may be an interference or force fit into the aperture through the tang of the mounting bracket.

[0092] The back plate of the clevis bracket may be fixed to the first end of a registration arm by welding the clevis bracket to the end of the registration arm, after having first cut off the existing hook end of the registration arm.

[0093] In some embodiments, the inwardly facing concave surface of the outer ring may have a Teflon® or other plastics material liner of low coefficient of friction, which means that the inner ring is fully self -lubricating with respect to the outer ring, and therefore no additional lubrication maintenance is required.

Refurbishment of existina known reaistration arms [0094] A method of replacing a known registration arm having a hook end by a spherical surface joint as described herein, so as to re -use or refurbish an existing registration arm may comprise: cutting the existing hook connector from a first or heel end of the registration arm; welding a clevis bracket of the type described in Figures 6 to 11 herein to the first end of the registration arm; removing an existing support bracket from a support structure such as a pull off arm or a drop bar or drop beam or like support structure; fitting a novel mounting bracket as disclosed herein to the support structure, the mounting bracket being of a type described with reference to Figures 6 to 11 herein, the mounting bracket having a tang having a central aperture there-through, a back plate, and one or more "U" bolts or another clamp type arrangement to fit the back plate to the support structure; inserting a swivel joint comprising an outer ring and an inner ring into the aperture in the tang of the support bracket; inserting the tang and articulated swivel joint between first and second side plates of the clevis bracket; passing a connecting pin through first and second apertures of the clevis bracket and through the central aperture of the inner ring of the swivel joint so that the connecting pin retains the clevis bracket to the inner ring of the swivel joint and thereby to the tang of the mounting bracket; and inserting a retaining pin through a portion of the connecting pin which protrudes to an opposite side of the clevis bracket from which the pin was inserted, to secure the connecting pin to the clevis bracket.

[0095] Where an existing known mounting bracket, for example as shown in Figures 4 and 5 herein is capable of being adapted for insertion of a spherical swivel joint, instead of providing a replacement novel mounting bracket as described in Figures 6 to 11 herein, in some circumstances it may be possible to adapt or modify the known mounting bracket either in situ, or preferably off-site in a workshop by boring or reaming out a circular cylindrical aperture having a circular cylindrical inwardly facing surface to replace the existing circular eye aperture of the existing known mounting bracket which has an inwardly facing donut shaped or torus -shaped circular cylindrical sides, subject to the remaining toroidal metal loop having sufficient strength.

Mechanical tolerances [0096] The mechanical tolerances between the inner ring of the rose joint, the outer ring of the rose joint and between the outer ring of the rose joint and the eye aperture in the tang are selected to be a close enough fit that there is no arcing between the inner and outer rings of the rose joint through the full range of movement of the rose joint in operation.

[0097] The outer ring of the rose joint may have an outer diameter and the circular aperture of the tang may have an inner diameter selected such that the outer ring fits in to the aperture in the tang by an interference fit (also called a press fit or a friction fit) in which the outer diameter of the outer ring is slightly larger than the inside diameter of the circular cylindrical aperture of the tang, so that once fitted in the tang, the outer ring securely retains in position in the tang and makes good electrical contact with the tang.

[0098] In other embodiments, the outer ring of the joint may be a clearance fit to the inner surface of the circular cylindrical aperture in the tang, so as to enable easy assembly of the outer ring to the tang, and to allow for some rotational movement of the outer ring within the aperture of the tang.

[0099] The tolerances between the convex part spherical outer surface of the inner ring and the concave pad spherical inner surface of the outer ring and the convex outer surface of the inner ring are preferably a clearance fit, such as to allow free articulation of the inner ring with respect to the outer ring in any direction, whilst not having any looseness or slack between the rotational movement of the inner ring and the outer ring, and keeping close mechanical contact between the concave and convex bearing surfaces.

Performance testina and assessment [0100] The inventors have submitted the novel connector and registration arm embodiments herein for finite element analysis including assessing the strength of the welds of the clevis bracket, and a software simulation of 6 million cycles of loading to simulate a 40 year operational life cycle of the connect registration arm. The results of the performance testing indicates a potential 40 year operational life cycle.

Advantages [0101] Specific embodiments disclosed herein may have an advantage of reducing or eliminating sparking between the end of a registration arm and a supporting pull off arm and thereby extend the operational life of both registration arms and pull off arms in the electric overhead line equipment for railways, and increase the reliability of overhead line equipment.

[0102] Specific embodiments herein may reduce the need for maintenance of registration arms and pull off arms on overhead electric line equipment as a result of eliminating or minimizing electrical arcing between the end of the registration arm and the mounting bracket which mounts the registration arm to the support structure.

[0103] Due to the close-fitting nature of the inner ring to the outer ring, "chatter" of the end of the registration arm is alleviated. By providing an inner ring which is either stainless steel or chrome plated steel, and an outer ring which has low coefficient material for example bronze or Teflon° or other suitable plastics material, and having a convex part-spherical surface, the joint is effectively self-lubricating and the need for additional lubrication maintenance is reduced or avoided.

Claims

Claims 1. A registration arm connector for connecting a registration arm to a support structure of an overhead line equipment, said registration arm comprising: an elongate beam having a first end and a second end; said connector comprising: a bracket comprising first and second spaced apart plates, said first plate having a first aperture and said second plate having a second aperture; a first ring having a convex part spherical outer surface; said first ring having an aperture therein; a second ring having a concave part spherical surface; wherein said first ring engages said second ring such that said convex part spherical surface of said first ring engages said concave part spherical surface of said second ring; and a pin for engaging through said apertures of said first and second spaced apart plates and through said aperture in said first ring.
2 The connector as claimed in claim 1, further comprising a tang having an aperture there through, wherein said second ring locates within said aperture of said tang.
3. The connector as claimed in claim 2, wherein a range of movement between a main plane bisecting said tang and lying perpendicular to said aperture through said tang and a main plane which bisects said bracket and lies equidistantly between said first and second side plates of said bracket, is in the range 0 -30°.
4. The connector as claimed in any one of the preceding claims wherein a fit between an outer surface of said outer ring and an inner surface of said aperture of said tang is an interference fit.
5. The connector as claimed in any one of claims 1 to 3, wherein an fit between an outer surface said second ring and an inner surface of said aperture through said tang is a clearance fit.
6. The connector as claimed in any one of the preceding claims, wherein an outer diameter of said convex part spherical surface of said first ring is a clearance fit to said concave part spherical surface of said second ring.
7. The connector as claimed in any one of preceding claims, wherein said first ring comprises a part spherical body having: a part spherical convex outer surface, a first substantially flat face, a second substantially flat face, wherein said first and second substantially flat faces lie diametrically opposed to each other on opposite sides of said part spherical body; and a circular cylindrical aperture extending through said body between said first and second substantially flat faces.
8. The connector as claimed in any one of the preceding claims, wherein said inner ring comprises stainless steel.
9. The connector as claimed in any one of the preceding claims, wherein said concave part-spherical surface of said second ring comprises a low friction coefficient material.
10. The connector as claimed in claim 10, wherein said low friction coefficient material is selected from the set: a plastics material; Teflon® bronze.
11. The connector as claimed in any one of the preceding claims, wherein, absent of said pin, said first ring may rotate with respect to said second ring throughout a full 3600 rotation in any plane.
12. A registration arm for an overhead line equipment, said registration arm comprising: an elongate beam having a first end and a second end, and a beam portion extending between said first and second ends, a plate having a circular cylindrical aperture there through; said plate extending such that a main plane bisecting said plate, and lying parallel to first and second planes which coincide respectively with first and second main outer surfaces either side of said plate, lies parallel to a main plane which bisects the whole of said beam portion, including said first and second beam ends.
13. An end connector for a registration arm, for connecting an end of a registration arm to a supporting structure, said end connector comprising a bracket, a rotatable joint, and a pin; said bracket comprising: a base plate; a first side plate extending from a first side of said base plate, said first side plate comprising a first aperture; a second side plate extending from a second side of said base plate, said second side plate comprising a second aperture; said first and second side plates facing opposite each other such that said first and second apertures lie opposite and in line with each other; said rotatable joint comprising an outer ring and an inner ring; said outer ring comprising an annular outer surface and a concave part spherical inner surface; said inner ring comprising a part spherical outer surface and a circular cylindrical aperture; wherein said inner ring locates in said outer ring such that said inner ring is rotationally moveable with respect to said outer ring; and wherein said pin engages through said first and second apertures of said first and second side plates, and through said aperture of said inner ring to locate said inner and outer rings between said first and second side plates, and to retain said inner and outer rings to said bracket; and a third plate having an aperture therethrough, said third plate moveably locating between said first and second plates, wherein said outer ring locates in said aperture of said third plate, such that said third plate retains to said bracket by said inner and outer rings, and by said pin.
14. A mounting bracket for mounting to an upright support structure of an overhead line equipment for railway, said mounting bracket comprising: 1 0 a back plate having an indented rear surface to fit around a portion of a said support structure; an extending portion comprising a flat plate, said portion extending outwardly from said back plate; said extending portion comprising a circular cylindrical inner surface surrounding an aperture through said extending portion.
15. The mounting bracket as claimed in claim 14, wherein said back plate comprises a channel for shaped for fitting to an upright surface of the support structure; and a main geometric central axis of said aperture through said extending portion lies across a main length direction of said channel.
16. The mounting bracket as claimed in claim 14 or 15, wherein said tang comprises a plate having first and second upright sides, said aperture extending between said first and second upright sides.
17. The mounting bracket as claimed in any one of claims 14 to 16 wherein said plate comprises a part toroidal loop extending around said aperture.
18. The mounting bracket as claimed in any one of claims 14 to 17, wherein said back plate comprises first and second spaced apart apertures; wherein said tang plate is located between said first and second spaced apart apertures.
19. A method of refurbishing a known registration arm for an overhead electrical line, for connecting to a support structure of said overhead line equipment, said method comprising: fitting a first plate to a first end of said registration arm, said first plate having a substantially circular cylindrical aperture which has a main geometric central axis which lies across a pair of parallel planes within which the registration arm lies, where each of said planes extends in a direction coincident with a main direction of said registration arm.
20. The method as claimed in claim 16, further comprising cutting a hook or a loop off said first end of said registration arm prior to fixing said first plate to said first end of said registration arm; and welding a bracket to said first end of said registration arm, said bracket comprising said first plate; wherein said bracket comprises a back plate, said first plate and a parallel opposing plate, said first plate and said opposing plate forming a clevis 25 arrangement.
21. A method of refurbishing a known registration arm for an overhead electrical line, and connecting said refurbished registration arm to a support structure of said overhead line equipment, said method comprising: fitting a first plate to a first end of said registration arm, said first plate having a substantially circular cylindrical aperture which has a main geometric central axis which lies across a pair of planes within which the registration arm lies, where each of said planes extends in a direction coincident with a main direction of said registration arm; securing a second plate to said support structure, said second plate having an aperture there through, said aperture extending between first and second sides of said second plate; securing said first plate to said second plate by means of a swivel joint having an inner part which has an outwardly facing pad spherical bearing surface, and an outer part which has an inwardly facing part spherical bearing surface, wherein the outwardly facing and inwardly facing part spherical bearing surfaces are in direct contact with each other; and securing the first plate to the swivel joint by passing a connector pin through an aperture in said first plate and through an aperture in said inner part of said joint.
22. The method of refurbishing a known registration arm for an overhead electrical line, and connecting said refurbished registration arm to a support structure of said overhead line equipment, as claimed in claim 18, further comprising: passing said connector pin through an aperture in said first plate; and passing said connector pin through an aperture in a further plate which lies on an opposite side of said swivel joint to said first plate.