Abstract:
The invention provides an improved device for the lubrication of railway tracks in the form of grease distribution bar ( 1 ) of simplified construction, which may be machined from a single piece of suitable material. This is possible because the greaseways ( 3 ) are simple, without multiple bifurcations forming complex distribution trees, thus allowing the internal greaseways ( 3 ) to be drilled or machined rather than requiring construction by layering multiple blades. In further aspects, the invention provides improved channels ( 6 ) and nozzles ( 22 ) for grease delivery, and improved grease delivery using a progressive distributor system ( 10 ) and improved means of rapid attachment and disengagement of such a device from the rail to be lubricated.

Description:
[0001]    The invention relates to the lubrication of the rails of railway tracks, in particular, an improved design of wayside lubricator. 
       BACKGROUND 
       [0002]    The principle of lubrication of railway tracks to minimise the wear and noise resulting from metal to metal contact between wheels and, in particular, the inner surface of the rail that comes into contact with the flange of the wheel of rolling stock, is well-known. Devices for applying such lubrication may be fitted to the wheels of rolling stock (‘on board’ systems) or to the track itself, especially at sites of high wear, such as bends and points (‘wayside’ systems). 
         [0003]    Although some systems spray oil, most wayside lubricators pump grease from a reservoir, through a series of pipes, to grease distribution bars mounted alongside the track. Such systems may be mechanical, hydraulic or electrically-driven. Usually the former two are actuated by passing trains contacting mechanical or hydraulic pumps, the latter by an induction sensor responding to the passing wheels. However pumped, all these systems feed grease onto the gauge face or surface of the rail through grease distribution bars or units. The bars or units are positioned on the side of the rail just below the wheel contact area. Grease deposited on the rail is picked up by the wheel and spread along the curve of the track. 
         [0004]    Currently known grease distribution bars are of a ‘multiplate’ configuration, with a single ‘balanced inlet’ for grease. That is, the bars are manufactured as a series of machined plates or ‘blades’, which are fitted together to provide the internal structure, and a single grease inlet feeds multiple outlets by means of branched ‘tree’ of successively bifurcating greaseways. It is important that all of the outlets remain clear and deliver grease efficiently, but very frequently the outlets become progressively blocked resulting in failure of the unit to deliver adequate lubrication. Not only does this result in increased wear and consequent increased maintenance costs, but rapid premature wear can result in failure and fracture of the rail and/or wheel, with potentially catastrophic results. 
         [0005]    Efficient lubrication also depends on effective presentation of the lubricant to the relevant surface of the rail gauge face and gauge corner with minimum waste and environmental contamination. Current systems frequently fail to present the grease efficiently due to poor design of the grease outlets. 
         [0006]    Finally, track maintenance requires regular access to the rails and consequent removal and repairs to or replacement of grease distribution bars. This removal and subsequent accurate replacement is frequently time consuming, dangerous and difficult, particularly where units become dirty, corroded or covered with misapplied grease. In addition, such maintenance exposures personnel to a degree of danger and reduction of such exposure is a significant safety consideration. 
         [0007]    There is therefore a need for an improved design of wayside lubricator to address these shortcomings. 
       SUMMARY OF INVENTION 
       [0008]    In a first aspect, the invention provides simplified construction of grease distribution bar, which may be machined from a single piece of suitable material. This is possible because the greaseways are simple, without multiple bifurcations forming complex distribution trees, allowing the internal greaseways to be drilled or machined rather than requiring construction by layering multiple blades. Any suitable material may be used, but aluminium has the advantages of being easy to machine and light to carry and manipulate. However, in some situations, steel or other alloy or metal may be preferable. The use of non-metal materials such as extruded polymers or, especially, composites is also disclosed. 
         [0009]    A common problem with multiple bladed (‘multiplate’) grease distribution bars is that, if set too high, the top edge of the unit makes contact with the passing train wheels, with the result that the wheels ‘nip’ the plates together, distorting the grease outlets and causing blockages. The current design overcomes this problem by both its single blade construction and the design of its grease outlets. This invention minimises current severe problems of blocked or damaged grease distribution bars and facilitates speedier maintenance, location and removal times of bars on track, thereby significantly improving safety and reducing costs. 
         [0010]    The invention provides a lubricating device for the rails of railway tracks comprising
       a. a grease distribution bar comprising a body presenting a plurality of outlet ports supplied by internal grease ways; and   b. a means of delivery of grease to said grease bar
 
characterised in that the body of said grease bar is of single piece construction.
       
 
         [0013]    As will be clear to any skilled person, ‘grease’ in this context includes any lubricant of suitable viscosity and other properties suitable for use. 
         [0014]    By ‘single piece construction’ is meant that the main body of the grease distribution bar is machined or cast from a single piece of metal, polymer, composite or other material, or extruded as a one piece unit, rather than being built up of a plurality of blades, sections or subunits. Conventionally, the internal greaseways of such grease distribution bars are complex and impossible to machine from a single block of material, necessitating a multi-bladed construction using individually machined plates. However, the use of simplified greaseways with essentially linear configurations allows them to be machined directly. In one preferred embodiment, the greaseways have diameters of between about 2 mm and about 15 mm, preferably between about 3 mm and about 10 mm. 
         [0015]    Preferably, grease is supplied to each outlet through a dedicated greaseway, By ‘dedicated’ is meant that each inlet leads directly to an outlet, rather than being interconnected via multiple bifurcations to three or more outlets The pump may be activated by a switching system that detects an oncoming train, several systems being well-known in the field. Alternatively, and especially on lines with low traffic densities, the pump may be activated at preset intervals by a timer. 
         [0016]    In another embodiment, bars of differing lengths may be affixed such as to apply grease to lubricate and reduce noise from adjacent ‘check rails’ which are aligned parallel with running rails to retain the wheel flange safely where there is an increased risk of train derailment i.e. curves of ‘tight’ radius, bridges and complex track layouts e.g. as at station approaches and ‘crossing lines’ or road crossings (S&amp;C). This embodiment may also be used to apply friction modifier lubricants effectively to the head of the rail. 
         [0017]    A second aspect of the invention relates to the delivery of grease to the outlet ports. According to this aspect of the invention, lubricant, preferably grease, is supplied to each outlet port in turn. Preferably, the grease is delivered by a progressive distributor device. Thus, rather than pumping grease into a single inlet and thence to all outlets simultaneously, the progressive distributor preferably provides a preset volume of grease to one outlet at a time, with delivery being progressive to each outlet in turn. Depending on the requirements of the situation, the distributor feeds lubricant to each of the ports in quick succession. Typically, the pump may cycle through 5 to 10 ports in 20 to 60 seconds. Alternatively, the progressive distributor may distribute to only some of the ports on each activation or may progress through more than one cycle of distribution so that each port is fed more than once. 
         [0018]    As a result of this, a complex tree of branching greaseways fed from a single common inlet is not required. Each outlet port is fed from a separate inlet, connected by a simple internal greaseway and, on each activation, a progressive distributor delivers grease to each inlet in turn. As well as simplifying construction, this arrangement also allows a relatively high pressure delivery to each outlet individually, minimising the risk of blockage, rather than the inevitable loss of outlet pressure resulting from a distribution tree to multiple outlets from a single inlet. 
         [0019]    Although there are clear advantages to the use of a progressive distributor-type in many situations, it will be clear to one of skill in the art that the single piece construction disclosed, with its low back-pressure, dedicated greaseway system can be advantageously employed with conventional high-pressure delivery systems (HPDSs), connected so as to deliver grease to each inlet simultaneously. 
         [0020]    The progressive distributor or HPDS may be conveniently attached to the outer (non-rail-facing) aspect of the body of the grease distribution bar and its multiple outputs each individually connected by a suitable line to a grease inlet. Preferably, these lines are attached to the inlets by means of quick-release couplings, to simplify maintenance. Especially preferred are threadless, “Quick-fix”-type couplings or similar. In one embodiment, the inlets are situated on the outer aspect of the body, and the hoses attach by means of elbow joints. This has the advantage of shortening the hoses required. Alternatively, the inlets may be on the bottom of the unit. In this arrangement, an essentially straight greaseway leading through the body from inlet to outlet port is possible, which has the added advantage that, should a blockage occur, the greaseway can be easily cleared by probing or independent purging. Preferably, low-cost, flexible grease lines and suitable hydraulic or pneumatic ‘Quick-fix’ fittings are used. Having such lines supplied pre-primed with grease further reduces the trackside maintenance time 
         [0021]    Alternatively, the progressive distributor or HPDS may be attached the inner (rail-facing) aspect of the body of the grease distribution bar so that when the unit is in position the progressive distributor or HPDS and associated hoses and couplings are concealed beneath the head of the rail and behind the unit, especially if the ‘elbow joint’ arrangement of inlets described above is used. This offers increased protection and greater security, especially when the track is in an urban situation. 
         [0022]    The inlet to the progressive distributor or HPDS is connected to an external reservoir and pump, preferably by a flexible connecting hose. The pump may be activated by the approaching train by any of a range of known means, for example induction sensors, or the pump may simply be activated by a pre-set timer. By way of example only, a common reservoir capacity is up to 37 kg for a mechanical or hydraulic unit to 90 kg for an electric unit. Mechanical/hydraulic units are powered by the passing trains. Electric units are powered by an ‘in situ’ battery charged by a solar panel or wind turbine. 
         [0023]    In an alternative embodiment, a plurality of progressive distributors or HPDSs are used, particularly where multiple, or longer, length units are required. 
         [0024]    A further advantage of the simplified greaseway arrangement is that it allows the use of more viscous lubricants than the conventional arrangement. This is particularly useful where the device is to be used in hot and/or very wet environments. To maintain their physical properties, lubricants for use in high temperatures may need to be ‘stiffer’ or more viscous, and where there is nevertheless a large diurnal variation in temperature, this may lead to lubrication failure at times of more moderate temperatures. Similarly, heavy, persistent rainfall may wash away less viscous lubricants. For instance, currently many grease-based systems use NLGI (National Lubricating Grease Institute) grade 1 lubricants, which are not ideal in all situations. The grease distribution bar of the current invention is useful for spreading NLGI grade 2 or 3 greases due its low back-pressure greaseways and use of a progressive distributor. 
         [0025]    In one preferred embodiment, the terminal portion of one or more greaseways bifurcates once to provide two outlet ports. This maintains the simple internal structure of the grease distribution bar, and such a terminal bifurcation is easily machined. However, the provision of two outlet ports per greaseway, each optionally fitted with a closeable valve such that grease flow may be diverted to either one of the outlet ports alone, allows any blockage that does occur in an outlet port quickly and conveniently to be cleared. By closing one of the valves the increased pressure forces grease to flow through the open outlet port, purging any blockage. Since the valves may easily be opened and closed without dismantling the device, such blockages as occur may be quickly cleared during routine maintenance inspections. Blockages of this type are typically caused by external debris contamination i.e. leaves, paper, human excrement or ‘spillage’ from passing trains. 
         [0026]    In a third aspect, the invention provides an improved design of grease outlet port. In one embodiment, the aim of the outlet port is to provide a somewhat free-standing column of grease, such that the grease is efficiently picked up by the flange of the passing wheel. In order to achieve this, the column is shaped and supported by an upwardly disposed channel or groove as it is extruded from the outlet aperture. Thus the outlet port preferably comprises an upwardly disposed channel, open on one aspect. In use, this channel presents a column of grease to the face of the rail to which the grease distribution bar is adjacent when fitted. The contact of the grease with the surface of the channel, whilst being free of contact on the opposite aspect, has the effect of lightly dragging the column towards the rail, rather than it collapsing away from the rail. 
         [0027]    In one preferred embodiment, the body of the grease distribution bar has an essentially upright flange, the inner (rail-facing) face of which is continuous with the inner (rail-facing) face of the body of the grease distribution bar and which is, in use, closely apposed to the face of the rail. In this embodiment the channel is in the outer face of the flange. Preferably, the base of the channel communicates with the outlet aperture, which is itself continuous with the internal greaseway. However, other arrangements which support the grease column by providing an effective channel are possible, for instance freestanding ‘half pipes’, detachable nozzles or similar structures. In addition, the flange need not be continuous, but may be discontinuous or of varying height as required adjacent the outlet apertures to support the emerging grease column. 
         [0028]    It is further preferred that the channel and outlet aperture are elongate, to optimise the shape of the grease column for spreading by the passing wheel. Alternatively they may be of circular section. The channel may correspond to approximately half the shape of the aperture or alternatively to less than half or more than half of its circumference or shape. Thus the channel may optionally include ‘undercuts’ and may partially enclose the extruded grease column. 
         [0029]    The spacing of outlet apertures along the grease distribution bar is dependent on the type of lubricant used and the particular application. In a typical example, the outlet apertures may be, for instance, 10 mm to 30 mm along their long axis (along the body of the unit) and about 10 mm to about 50 mm apart. 
         [0030]    It is also preferred that, in order to further encourage the formation of a stable grease column and prevent ‘drooping’ away from the rail face, the longitudinal axis of the upwardly disposed channel is inclined towards the inner (rail-facing) face aspect of the device. More preferably the channel is angled between about 3° and about 10°; most preferably it is angled at about 5°. Preferably the angle of the channel is a continuation of the angle of the terminal portion of the greaseway and outlet aperture. 
         [0031]    In an alternative embodiment, each grease outlet port communicates with a nozzle assembly rather than with a channel in a flange. Preferably, each nozzle assembly comprises a laterally compressed nozzle, or at least a nozzle comprising an elongate orifice so as to provide a flattened sheet of grease and to present this to the rail surface. A compressed or flattened nozzle shape can be positioned near to the rail with reduced risk of contact with passing wheels. This significantly reduces the risk of contact with the wheels, compared with a steel bar, and therefore the risk of a possible derailment of a train. Alternative nozzle shapes are possible, including fan-shaped or curved, depending in the precise shape of rail to be lubricated. Preferably each nozzle is adjustable so that precise positioning with respect to the rail, taking into account curvature or other irregularity, is possible, optimising grease application. A particularly preferred embodiment of a nozzle assembly comprises nozzle and a body, connected by an adjustable link, such as a ball and socket arrangement. Alternatively, the nozzle is deformably flexible. Nozzles and/or nozzle assemblies are preferably constructed of a suitable plastics, nylon or metal (such as aluminium) material suitable to resist corrosion and blockage in a trackside environment. Nozzle assemblies may conveniently be fitted to the outlet ports of the body of the grease distribution bar by a threaded connection. Damaged or blocked nozzle assemblies are thereby easily removed and replaced. Each nozzle may be shaped with one extruding face machined away to promote the grease towards the rail gauge face to provide good pick up by the trains wheels and better lubrication of the track and wheels. Nozzles constructed of relatively soft or brittle materials have the advantage that, should contact with the train wheels occur, the risk of damage or derailment to the train, as well as damage to the body and other components of the lubrication device, are minimised. Dislodged nozzles or fragments thereof are also unlikely to cause a risk to trains or trackside equipment, points etc. 
         [0032]    In a final aspect, the invention provides rapid and convenient means of moving the device away from the rail to allow for maintenance such as rail grinding. The grease distribution bar is fixed to a rail-engaging base unit, preferably via bracket member) by means of a slideable attachment unit allowing disengagement of the device from the rail by a lateral translational movement, followed by upward tilting of the device by means of a rotational movement of the attachment unit. Preferably, the slideable attachment unit is spring-loaded and self-retaining. In normal use, the rail-engaging base unit is firmly attached to the foot of the rail and the slideable attachment unit is secured in position by means of a locking bolt or similar, with a second attachment point taking the form of pivot bar in an elongate slot. When the locking bolt is removed, the pivot bar arrangement allows the attachment unit, together with the grease distribution bar, to be slid away from the rail, with the pivot bar sliding within the slot. At any point where there is sufficient clearance, the attachment unit may be pivoted allowing the whole device to swing upwards clear of the rail and of the ground. Not only does this afford access to the rail but also allows easy inspection of the device. A flexible connection between the progressive distributor pump and the external grease reservoir allows the translational and rotational movements required. This attachment unit also provides for the grease distribution bar to be supplied in a ‘pre-assembled’ state, such that speedy and safe location to the track may be achieved with the bar pre-fixed in a safe orientation, secured by the spring-loaded base unit to allow staff to move to safety in the event of an approaching train. 
         [0033]    In one preferred embodiment, therefore, the lubrication device according to the current invention comprises a spring-loaded base unit, said lubrication device being capable of pre-assembly to allow rapid attachment to the rail by means of said spring-loaded bolt base unit. 
         [0034]    As will be cleared to a skilled person, the device of the current invention may also be configured for multiple applications, such as use with a curve rail, check rail and for rail head lubrication. This flexibility greatly reduces manufacturing costs for the main body of the device. 
     
    
     
       DETAILED DESCRIPTION OF THE INVENTION 
         [0035]    The invention will now be described in more detail, with reference to the drawings, as follows. 
           [0036]      FIG. 1A  shows a first embodiment of the device from the outer rail side aspect. 
           [0037]      FIG. 1  B shows a second embodiment of the device from the inner rail side aspect. 
           [0038]      FIG. 2  shows detail of the grease outlet port configurations.  2 A shows a vertical section through the body of the grease distribution bar, viewed along its long axis.  2 B shows a plan view (from ‘A’) of a single outlet port.  2 C shows an enlarged detail of  2 A.  2 D shows a detailed view of an outlet port with extruded grease column.  2 E shows an alternative configuration with a discontinuous flange. 
           [0039]      FIG. 3  shows a sectional view of the purging valve arrangement of the ‘double outlet port’ version of the device. 
           [0040]      FIG. 4  shows a sectional view along the long axis of the device in place adjacent the rail. 
           [0041]      FIG. 5  shows the formation of grease columns during extrusion from the outlet ports. In A, grease is shown beginning to emerge from the elongate outlet aperture; in B, the column is beginning to form, in contact with the channel in the flange ( 3 ); in C a full height column is shown standing clear of the flange and presented in an optimal position to be collected by the passing wheel flange when the device is in place. 
           [0042]      FIG. 6  shows a sectional view of an embodiment with an adjustable nozzle assembly. 
           [0043]      FIG. 7  shows an embodiment of the ‘slide and tilt’ clamping system to allow speedy safe removal of the bar for rail grinding, tamping or repairs to the bar. 
           [0044]      FIG. 8  shows an alternative embodiment with a base block engaged with the rail via spring-loaded J-bolt for rapid engagement or disengagement. 
           [0045]      FIG. 9  shows the device configured for lubrication of a check rail. 
       
    
    
       [0046]    Referring particularly to  FIGS. 1A ,  1 B and  2 , the body of the grease distribution bar ( 1 ) comprises a plurality of grease inlets ( 2 ), which communicate by internal greaseways ( 3 ) with outlet ports ( 4 ) on the upper surface of the device. A suitable unit is approximately 700 mm long with multiple fixing holes drilled, which is long enough to straddle rail sleepers and to allow flexibility as to the location of fixing clamps or brackets, or the attachment of the progressive distributor or HPDS pump, and yet is short enough to take account of track curvature and other trackside equipment. Double length, longer or shorter units are clearly possible for special applications. For such longer units, one or more further progressive distributor or HPDS might be necessary. Typically, the body of the grease distribution bar may be approximately 85 mm high and approximately 20 mm thick, although the dimensions are not critical except insofar as the body must be suitable to fit with differing rail sections, preferably largely within the concavity of the ‘web’ of the rail, between the head and the foot. The body for the bar utilising detachable nozzles will be of different section and configuration to facilitate the nozzles and progressive distributor or HPDS. 
         [0047]    Each outlet port comprises an outlet aperture ( 5 ), preferably elongate and continuous with an upwardly-disposed channel ( 6 ), which, in use, serves to support and guide the extruded grease so that it forms a stable column ( 7 ). In one embodiment, the channel ( 6 ) is formed in an essentially upright flange ( 8 ). Preferably, the flange is approximately 2 mm thick and about 10 to 20 mm high, although the exact dimensions are not critical. Grease is supplied from an external reservoir and pump, preferably by a flexible hose ( 9 ), to a progressive distributor or HPDS ( 10 ), which then feeds each of the grease inlets ( 2 ) in turn or simulataneously, connected by suitable (preferably flexible and preferably pre-grease-primed, lines ( 11 ) and utilising ‘quick fit’, low cost and ‘safe maintenance’ hydraulic fittings, or suitable pneumatic fittings. Alternatively, the grease inlets may be on the underside of the body of the unit ( 2 *). A suitable progressive distributor is the Lincoln SSV (M06-10C). As an example, such a device may discharge approximately 0.2 ml grease per stroke and may cycle through discharging 8 ports in approximately 30 seconds. In an alternative embodiment, especially for double-length, or longer, units, more than one progressive distributor or HPDS may be used in order to supply grease to a significantly increased number of outlets. 
         [0048]    The use of double length or longer bars ensures the effective correct application of grease to the full circumference of the the train wheels for transfer down the track gauge face and gauge corner. This will minimise the onset of rail cracking and unexpected breakage. 
         [0049]    In a preferred embodiment, the channel ( 6 ) is inclined so that, in use and fitted to the rail ( 12 , as shown in  FIG. 4 ), the extruded grease column is slightly directed towards the rail ( 12 ), available for contact with and spreading by, the flange of a passing train wheel ( 13 ), and is also encouraged to remain in contact with the channel ( 6 ). The communicating greaseway may be similarly inclined ( 3 ,  FIG. 4 ). 
         [0050]    As shown in  FIG. 3 , in one embodiment, the terminal portion of each greaseway bifurcates once so as to provide two outlet ports ( 4 ). Distal to the bifurcation, each greaseway is fitted with a valve ( 14 ,  15 ). When open ( 14 ), the valve allows grease to pass into the outlet aperture. In normal use, both valves are left open and both outlet ports operate. However, should one of the ports become blocked, the valve of the other port may be closed ( 15 ) diverting the whole flow to the blocked port. The extra pressure generated purges the port and clears the blockage, after which both valves may be opened to resume normal functioning. 
         [0051]      FIG. 6  shows an alternative version of the device having an adjustable nozzle assembly ( 21 ) instead of the flange and channel arrangement. The nozzle assembly ( 21 ) comprises a nozzle ( 22 ) and a body ( 23 ). The nozzle is adjustable, preferably by means of a flexible or ball-and-socket type of linkage allowing angular movement of the nozzle in any direction. The body ( 23 ) may be removeably attached to the outlet port, preferably by means of a screw thread. Grease may fed into the device from either side or from the base of the device The nozzle type grease outlet may be machined away on one side such that the extruding grease will adhere to the remaining opposite face and subsequently be properly transferred onto the gauge corner and gauge face of the rail. This nozzle outlet shape minimises the grease falling away from the rail. 
         [0052]    In one embodiment, the device is secured in position by means of a ‘slide and tilt’ clamping system, as shown in  FIG. 7 . The body of the grease distribution bar ( 1 ) is attached via a bracket member ( 16 ) to a slideable attachment unit ( 17 ), which, in normal use, is fixed to a rail-engaging base block ( 24 ) by means of a locking bolt ( 18 ) and a pivot bar ( 19 ). The base unit is firmly attached to the foot of the rail. The locking bolt, which may be spring-loaded, ( 18 ) passes through aligned holes in the base unit and attachment unit ( 17 ), but is removable. The pivot bar ( 19 ) is attached to the base unit but is free to slide in a longitudinally disposed slot ( 20 ) in the attachment unit ( 17 ). When the locking bolt ( 18 ) is removed, the attachment unit ( 17 ) may be both slid along its long axis, thus moving the device away from the rail by a translational motion, and also swung upwards, the pivot bar ( 19 ) rotating in the slot ( 20 ), to lift the device completely clear of the rail and the ground. 
         [0053]    In one alternative arrangement, the slideable attachment unit may be spring-loaded such that the unit is urged against the rail but may be withdrawn and the device disengaged, manually. 
         [0054]    As shown in  FIG. 8 , a further alternative is that the base block ( 24 ) to which the device is attached, is itself attached to the rail by means of, for example, a J-bolt or similar ( 25 ). Optionally, the base block ( 24 ) may be spring-loaded (spring,  26 ) such that the base block is urged against the rail but is capable of being withdrawn manually. The tension may be adjustable by, for instance, a helical spring ( 26 ) and adjustable retaining nut ( 27 ) as shown. 
         [0055]    In a further embodiment, the device may be configured for the lubrication of a check rail ( 28 ,  FIG. 9 ). An extended nozzle ( 29 ) passes across the head of the check rail ( 28 ) to deliver grease ( 30 ) to gauge corner and face of the rail and the outer surface of the flange of the wheel ( 31 ).