Railway-maintenance apparatuses and method of performing a maintenance action on a railway component of a railway

Abstract

A railway-maintenance apparatus (10) is provided for the autonomous maintenance of railway components (12). The railway-maintenance apparatus (10) comprises: a chassis (16) having a wheelset configured to move along a railway (14); a railway-maintenance head (38) being in-use connected to the chassis (16), the railway-maintenance head (38) having a railway-maintenance tool (40) for engaging with and performing a maintenance action on a railway component (12) of the railway (14); a position sensor configured to generate a position-sensor output indicative of a position of the chassis (16) and / or railway-maintenance head (38) relative to a reference point of the railway (14); and a programmable logic controller (62) in communication with the position sensor, the programmable logic controller (62) being configured to generate control instructions for the railway-maintenance apparatus (10) based on the position-sensor output.

Description

[0001] Railway-Maintenance Apparatus

[0002] The present invention relates to a railway-maintenance apparatus particularly but not exclusively for the autonomous maintenance of railway components. The invention further relates to a railwaymaintenance apparatus for the maintenance of a plurality of different railway components. The invention additionally relates to a method of performing a maintenance action on a railway component of a railway.

[0003] Railway-maintenance apparatuses are commonly utilised for the maintenance of the railway components of a railway. An example of one of these railway components would be a rail clip, which is used to connect railway tracks to the sleepers of the railway. The removal of railway components may be necessary in a variety of scenarios, for example, when needing to perform maintenance on specific section of track, thereby necessitating its disconnection from the sleepers. Additionally, the railway components may require replacing, and therefore a railway-maintenance apparatus is needed to facilitate their removal and installation.

[0004] An issue with such railway-maintenance apparatus is that they are manually operated. This is not only taxing for the operator due to the typically large weight of the railway-maintenance apparatus, but it also can be harmful for the operator due to the transfer of vibrations from the railwaymaintenance apparatus. Furthermore, the necessity to manually operate the railway-maintenance apparatus at each railway component in turn can be both physically and mentally taxing for an operator of the apparatus, resulting in operator fatigue.

[0005] A further disadvantage is that, due to their typically large weight, the railway-maintenance apparatus has to use an external device, such as a crane, in order to be deployed and withdrawn from the railway. Not only is this time consuming, but it is also costly for the operator, as it requires the procurement of a device large enough to be able to carry the railway-maintenance apparatus. Additionally, many railway-maintenance apparatus are limited by having a fixed wheelset width. This is a disadvantageous aspect of current railway-maintenance apparatus as many different railway networks comprise different gauges, the gauge being the distance between the rails of a railway. Gauge width does not just vary between different countries, but it can even vary within the same country, and / or within the same local rail network. For example, in Australia there can be up to three different gauges utilised within the same local rail network. A fixed wheelset width means that the railway-maintenance apparatus is prevented from being utilised on a wide variety of different railways, and instead is constrained to just a singular railway gauge, restricting the applicability of the railway-maintenance apparatus.

[0006] It is an object of the present invention to reduce or substantially obviate the aforementioned problems.

[0007] According to a first aspect of the invention there is provided a railway-maintenance apparatus comprising: a chassis having a wheelset configured to move along a railway; a railway-maintenance head being in-use connected to the chassis, the railway-maintenance head having a railway-maintenance tool for engaging with and performing a maintenance action on a railway component of the railway; a position sensor configured to generate a position-sensor output indicative of a position of the chassis and / or railway-maintenance head relative to a reference point of the railway; and a programmable logic controller in communication with the position sensor, the programmable logic controller being configured to generate control instructions for the railwaymaintenance apparatus based on the position-sensor output.

[0008] The chassis is the main structural component of the railway-maintenance apparatus. The railwaymaintenance head facilitates the maintenance of the railway components of the railway. The position sensor facilitates the autonomous operation of the railway-maintenance apparatus, as it enables the railway-maintenance apparatus to know where it is relative to a reference point, for example, the sleepers of the railway. By knowing where it is relative to the reference point, the programmable logic controller is able to generate control instructions for the movement of the chassis along the railway.

[0009] Preferably, the programmable logic controller may in-use autonomously operate the railwaymaintenance apparatus.

[0010] In-use, the autonomous operation of the railway-maintenance apparatus obviates the need for constant user inputs to be applied to the said railway-maintenance apparatus in order to perform maintenance, thereby increasing the ease of use of the railway-maintenance apparatus.

[0011] Preferably, the chassis may comprise a drive means fordriving the wheelset along the railway, the control instructions controlling the drive means.

[0012] The drive means actions the control instructions generated by the programmable logic controller. An example of the said drive means would be a hydrostatic drive system, with the programmable logic controller’s control instructions producing a hydraulic response in the hydrostatic drive system that results in the motion of the chassis.

[0013] More preferably, the railway-maintenance apparatus may further comprise a power module being releasably engageable with the chassis, the power module being operatively connected to the drive means.

[0014] The power module is necessary for powering the drive means and the rest of the railwaymaintenance apparatus. The power module being releasably engageable with the chassis enables its easy replacement and / or maintenance should it fail.

[0015] Preferably, the railway-maintenance tool may be complementarily formed to the railway component.It is desirable for secure engagement that the railway-maintenance tool is complementarily formed to the railway component, with this also increasing both the speed and reliability of maintenance operations.

[0016] Optionally, the railway-maintenance head may be releasably engageable with the chassis.

[0017] The railway-maintenance head being releasably engageable with the chassis allows for different heads, having different railway-maintenance tools for example, to be easily engaged and disengaged from said chassis.

[0018] Preferably, a plurality of railway-maintenance heads may be provided, each one of the plurality of heads being selectably engageable with the chassis, and each one of the plurality of railwaymaintenance heads having a different railway-maintenance tool.

[0019] The provision of a plurality of railway-maintenance heads with different railway-maintenance tools enables an operator of the railway-maintenance apparatus to easily switch from the maintenance of one type of railway component to another. This is desirable as different countries and rail networks have different railway components, and therefore the ability to easily switch railwaymaintenance heads, and consequently railway-maintenance tools, increases the applicability of the railway-maintenance apparatus.

[0020] Optionally, the railway-maintenance apparatus may further comprise a status sensor being configured to generate a status-sensor output indicative of a status of the railway component, the programmable logic controller being configured to generate control instructions for the railwaymaintenance apparatus based on the status-sensor output.

[0021] The status sensor provides the railway-maintenance apparatus, in combination with the programmable logic controller, with the capability to determine whether a railway component requires maintenance. This prevents unnecessary maintenance being conducted on a railway component, which would incur costs for little benefit, in addition to wasting time for what is typically a time-critical operation.

[0022] Preferably, the railway-maintenance head may comprise at least one hydraulic connection, each one of the at least one hydraulic connection having a distinct operative motion.

[0023] The at least one hydraulic connection provides a means through which instructions from the programmable logic controller may be actioned. The distinct operative motions enable the railwaymaintenance head to perform several actions.

[0024] More preferably, the operative motion may comprise one of: a screw operation; a grip and release operation; a horizontal operation; or a vertical operation.

[0025] These motions are desirable as they facilitate the maintenance of the railway component. The screwing and grip and release operations enable the railway-maintenance tool of the railway-maintenance head to engage and perform maintenance with the railway component. The horizontal and vertical operations facilitate the three-dimensional movement of the railwaymaintenance tool.

[0026] Preferably, the wheelset may be dimensioned to a gauge of the railway.

[0027] The wheelset must be dimensioned to the gauge of the railway for the chassis to be able to move along the railway.

[0028] More preferably, a width of the wheelset may be adjustable to be usable with a plurality of railway gauges.

[0029] The width of the wheelset being adjustable allows for flexible usage of the railway-maintenance apparatus, giving it the capability to be used on multiple different railways that have distinct railway gauges.

[0030] Optionally, the width may be adjustable in a range of 600mm to 2000mm.

[0031] This is the range within which the most widely used railway gauges lie.

[0032] Preferably, the wheelset may comprise a plurality of indexed locations corresponding to a plurality of different widths.

[0033] The plurality of indexed locations corresponds to a plurality of common railway gauges, such as the standard gauge, Russian gauge, Cape gauge and metre gauge. This enables an operator of the railway-maintenance apparatus to quickly and reliably set a width of the wheelset to a specific railway gauge, particularly useful during cross-border operations.

[0034] Preferably, the chassis may further include at least one continuous tread for moving the railwaymaintenance apparatus when not on the railway.

[0035] The at least one continuous tread enables the railway-maintenance apparatus to move independently of the railway. This is beneficial as it enables the railway-maintenance apparatus to move without the need of an external device, such as a crane, when it is being moved from a storage location or a transport vehicle to the railway. The use of these external devices can be costly, due to the necessity to either rent or buy such devices.

[0036] More preferably, the chassis may comprise at least one actuator for altering a configuration of the at least one continuous tread, the at least one continuous tread being adjustable between a lowered configuration and a raised configuration.

[0037] The ability to change between the different configurations, facilitated by the at least one actuator, enables the wheelset to not be obstructive when moving off of the railway in the lowered configuration, and also enables the at least one continuous tread to not be obstructive when moving on the railway in the raised configuration.Optionally, the railway-maintenance apparatus may further comprise at least one tread motor for powering the at least one continuous tread.

[0038] The at least one tread motor, preferably being a two-speed tread motor, provides the at least one continuous tread with a source of power for generating movement.

[0039] Optionally, the railway-maintenance apparatus may further comprise a sleeper lifting component. The sleeper lifting component holds the sleeper of the railway steady such that the railwaymaintenance tool may securely engage with the railway component.

[0040] Optionally, the railway maintenance-apparatus may further comprise a user input associated with the programmable logic controller to permit manual control of the railway-maintenance apparatus. The ability to operate the railway-maintenance apparatus manually allows the operator of the railway-maintenance apparatus to control it in situations where, for example, the programmable logic controller has failed.

[0041] Preferably, the railway-maintenance tool may be configured to engage with a rail clip.

[0042] The rail clip is the primary railway component for which the use of the railway-maintenance apparatus is envisaged for, with the maintenance of rail clips being a frequent operation on railways. As such, it is desirable for the railway-maintenance tool to be engageable with rail clips. Optionally, the railway-maintenance tool may be configured to engage with a rail clip selected from the list of: Pandrol™ Fastclip FC; Pandrol™ Fastclip FE; Pandrol™ Fastclip FD; Pandrol™ e-Clip; Pandrol™ e+- Clip; Pandrol™ PR; Pandrol™ Safelok series; or any Vossloh™ rail clip.

[0043] These are the types of rail clips that are most commonly utilised, and therefore the provision of a railway-maintenance tool that is able to engage with one of these rail clips is advantageous. Optionally, the railway-maintenance tool may be configured to engage with a fishplate.

[0044] Whilst the fishplate is not a primary railway component for which the use of railway-maintenance apparatus is imagined, the ability to use the railway-maintenance apparatus with varying components such as fishplates is desirable as it increases the flexibility of its use. Consequently, it is desirable for the railway-maintenance tool to be engageable with fishplates.

[0045] According to a second aspect of the invention there is provided a railway-maintenance apparatus comprising: a chassis having a wheelset configured to move along a railway; and a railwaymaintenance head being in-use connected to the chassis, the railway-maintenance head having a railway-maintenance tool for engaging with and performing a maintenance action on a railway component of the railway; wherein the railway-maintenance head is releasably engageable with the chassis to permit selectable interchange of different railway-maintenance heads.The releasably engageable railway-maintenance head allows for the railway-maintenance apparatus to be utilised for a variety of different railway components. Additionally, the ability to disengage the railway-maintenance head from the railway-maintenance apparatus facilitates easier maintenance, both of the chassis and of the railway-maintenance head.

[0046] Preferably, a plurality of railway-maintenance heads may be provided, each one of the plurality of heads being selectably engageable with the chassis, and each one of the plurality of railwaymaintenance heads having a different railway-maintenance tool.

[0047] Having the railway-maintenance apparatus be provided with a plurality of railway-maintenance heads is desirable as it enables an operator of the railway-maintenance apparatus to easily swap out the railway-maintenance head depending on the railway component being maintained.

[0048] More preferably, the railway-maintenance apparatus may further comprise a position sensor and a programmable logic controller, the position sensor configured to generate a position-sensor output indicative of a position of the chassis and / or railway-maintenance head relative to a reference point of the railway, the programmable logic controller in communication with the sensor and being configured to generate control instructions for the railway-maintenance apparatus based on the position-sensor output.

[0049] The provision of the position sensor and programmable logic controller allows for the railwaymaintenance apparatus to operate autonomously, enabling the chassis to be selectably moved depending on the positional location of the railway-maintenance apparatus.

[0050] According to a third aspect of the invention there is provided a method of performing a maintenance action on a railway component of a railway, the method comprising the steps of: a] providing a railway-maintenance apparatus in accordance with the first aspect of the invention; b] engaging the railway-maintenance tool with the railway component; and c] performing the maintenance action on the railway component.

[0051] The provided method is how the railway-maintenance apparatus is typically used in practice, with this method facilitating the fast and reliable maintenance of railway components.

[0052] The invention will now be more particularly described, by way of example only, with reference to the accompanying drawings, in which:

[0053] Figure 1 shows an isometric view of a first embodiment of a railway-maintenance apparatus in accordance with the first aspect of the invention;

[0054] Figure 2 shows an isometric view from the rear of the railway-maintenance apparatus of Figure 1 , the railway-maintenance apparatus being in-use positioned on a railway;Figure 3 shows an isometric view from the side of the railway-maintenance apparatus of Figure 1 without a railway-maintenance head being engaged with a chassis of the railwaymaintenance apparatus;

[0055] Figure 4 shows an isometric view of a first railway-maintenance head that is engageable with the railway-maintenance apparatus of Figure 3;

[0056] Figure 5 shows an isometric view of a second railway-maintenance head that is engageable with the railway-maintenance apparatus of Figure 3; and

[0057] Figure 6 shows an isometric view from below of the railway-maintenance head of Figure 5.

[0058] Referring to Figure 1 there is indicated a railway-maintenance apparatus, referenced globally at 10, and which is suitable for the automated maintenance of railway components 12 of a railway 14, as shown, for example, in Figure 2.

[0059] The railway-maintenance apparatus 10 comprises a chassis 16 having a wheelset configured to move along the railway 14. The wheelset comprises at least one wheel 18, wherein the depicted embodiment the wheelset comprises a plurality of four wheels 18.

[0060] The chassis 16 comprises at least one rail axle 20 to which the wheels 18 of the wheelset are connected. In the depicted embodiment the railway-maintenance apparatus 10 comprises two rail axles 20, each rail axle 20 comprising two wheels 18 being bolted on.

[0061] The chassis 16 comprises a drive means that drives the wheels 18, consequently moving the chassis 16 along the railway 14. The wheels 18 are connected to the drive means, the drive means itself being operatively connected to a power module 22 of the chassis 16, the power module 22 powering the railway-maintenance apparatus 10. In the depicted embodiment the power module 22 is a diesel engine.

[0062] In the depicted embodiment, the drive means is a hydrostatic drive system 24. The use of a hydrostatic drive system 24 obviates the need for complex gearing, such as that present with a mechanical drive means, and instead enables precise speed control at the low speeds at which the railway-maintenance apparatus 10 operates. The drive means comprises hydraulic controls, utilising for example solenoid operated valves with a manual override in case of an emergency recovery scenario.

[0063] The chassis 16 also comprises at least one illumination element 26, which in the depicted embodiment is in the form of lights connected to a first end 28, a second end 30 and two side portions 32 of the chassis 16. This first end 28 is envisioned to be the forward-facing surface relative to the direction of travel, however, due to the drive means 24 facilitating movement in both longitudinal directions of the chassis 16, the second end 30 may also be the forward-facing surface relative to the direction of travel.The chassis 16 of the railway-maintenance apparatus 10 also has at least one continuous tread 34 for enabling the railway-maintenance apparatus 10 to individually connect and disconnect from the railway 14. In the depicted embodiment, the chassis 16 comprises two continuous treads 34, the continuous treads 34 being positioned perpendicular to a longitudinal axis AL of the railwaymaintenance apparatus 10 and connected to a bottom surface of the chassis 16 in between the rail axles 20. Of course, an alternative construction would involve the use of traditional wheels which allowed the railway-maintenance apparatus 10 to be driven off-rail, in lieu of or in addition to the continuous tread 34.

[0064] The chassis 16 comprises at least one actuator 36, preferably a hydraulic actuator 36, which connects the chassis 16 to the at least one continuous tread 34. The at least one actuator 36 facilitates two configurations of the at least one continuous tread 34: a raised configuration, for when the wheelset is positioned on the railway 14 and the railway-maintenance apparatus 10 is in-use performing maintenance; and a lowered configuration, for when the wheelset is not positioned on the railway 14 and the railway-maintenance apparatus 10 is in transit.

[0065] The lowered configuration allows the railway-maintenance apparatus 10 to move independent of the railway 14, with the operation of the at least one continuous tread 34 enabling the railwaymaintenance apparatus 10 to, for example, drive off of a transport vehicle and onto the railway 14. Once the railway-maintenance apparatus 10 is on the railway 14, the activation of the at least one actuator 36 has the effect of lowering the chassis 16, and consequently the wheelset, onto the railway 14. Once the wheelset is on the railway 14, the activation of the at least one actuator 36 has the effect of raising the at least one continuous tread 34 off of the railway 14 and into the raised configuration, thereby allowing the railway-maintenance apparatus 10 to conduct maintenance. Once maintenance has concluded, the at least one continuous tread 34 is adjusted into the lowered configuration by the at least one actuator 36, enabling the railway-maintenance apparatus 10 to drive off of the railway 14 and onto the transport vehicle. The at least one continuous tread 34 is powered by at least one tread motor that enables both clockwise and anti-clockwise motion of the at least one continuous tread 34, wherein the depicted embodiment the at least one tread motor comprises a two-speed tread motor.

[0066] The at least one continuous tread 34 comprises a rubber material, providing good traction and durability whilst at the same time being relatively light for easier transport. However, it would also be possible for the at least one continuous tread 34 to comprise a metallic material, or a metalrubber combination. Metal increases the durability of the at least one continuous tread 34, however this comes at the expense of a greater weight, which complicates transport.

[0067] The chassis 16 has a width Wc being less than 2.5m that enables it to easily fits onto, for example, the bed of a truck or rail car. In the depicted embodiment, the width Wc of the chassis 16 is 2.4m.Furthermore, the railway-maintenance apparatus 10 is able to navigate difficult terrain in the lowered configuration due in part to the significant ground clearance Hccof the chassis 16, which is at least 150mm, and which in the depicted embodiment is 156mm. The ability to navigate challenging terrain is further facilitated by the chassis 16 having a gradeability of 45 degrees in the lowered configuration. The railway-maintenance apparatus 10 has a gradeability of 30 degrees in-use on the railway 14.

[0068] The railway-maintenance apparatus 10 further comprises a railway-maintenance head 38, with at least one railway-maintenance head 38 in-use connected to the chassis 16. The railwaymaintenance head 38 has a railway-maintenance tool 40 for engaging with and performing a maintenance action on a railway component 12 of the railway 14, with an example of this seen in Figure 2. The railway-maintenance tool 40 is complementarily formed to the railway component 12.

[0069] In the depicted embodiment, there is a railway-maintenance head 38 connected to the chassis 16 on both side portions 32 of the chassis 16, giving the railway-maintenance apparatus 10 a total of two railway-maintenance heads 38. The presence of a railway-maintenance head 38 in both side portions 32 of the chassis 16 facilitates the simultaneous maintenance of railway components 12 on both rails 42 of the railway 14.

[0070] Each wheel 18 of the wheelset is complementarily formed to the rails 42 of the railway 14. The wheelset is also dimensioned to a gauge WG of the railway 14, enabling the chassis 16 to move along said railway 14. To facilitate the dimensioning of the wheelset to complement the gauge WG of the railway 14, the wheelset has a width Ww being measured between the wheels 18 on each rail 42.

[0071] The width Wwof the wheelset is adjustable, which enables the railway-maintenance apparatus 10 to be usable with a plurality of gauges. This is desirable as different countries have different gauges, and therefore the ability to change the width Ww allows the railway-maintenance apparatus 10 to be used in a wide variety of countries. The width Ww may be adjusted to a value in the range of 600mm to 2000mm, as this is the range within which most track gauges lie. However, it may be convenient to have a width Ww that is adjustable in a range of 1000mm to 1650mm, as this a shorter range comprising the most common track ranges. This is desirable if wanting to limit the mechanical complexity of the railway-maintenance apparatus 10.

[0072] In addition to the width Ww of the wheelset being adjustable, the wheels 18 of the wheelset are replaceable to accommodate any rail profile. This further facilitates the use of the railwaymaintenance apparatus 10 with a plurality of different types of railways 14, as different railways 14 may have differently shaped rails 42.

[0073] The rail axles 20 comprise a plurality of indexed locations for a plurality of different widths Ww, these widths Ww corresponding to a variety of commonly used gauges, such as: metre gauge (1000mm); standard gauge (1435mm); Cape gauge (1067mm); or Russian gauge (1520mm).In the depicted embodiment the indexed locations are discrete, each indexed location having a fixing point to which each wheel 18 of the wheelset can be engaged. However, in a separate embodiment of the railway-maintenance apparatus 10 that is not depicted, the indexed locations are on a continuous scale. This is done in the form of a guide rail of the chassis 16, the wheelset engageable at any point within the guide rail.

[0074] The second end 30 of the chassis 16 has at least one indicator 44 for notifying others of the presence of the railway-maintenance apparatus 10. At least one indicator 44 may be a ‘reversing’ indicator that informs others that the railway-maintenance apparatus 10 is moving in a ‘reverse’ direction, which is essentially in a longitudinal direction extending from the second end 30. Another indicator 44 may be reflective and provide an indication to another rail vehicle of the presence of the railway-maintenance apparatus 10 on the railway 14 in low light conditions.

[0075] As most railway components 12 are also connected to a sleeper 46 of the railway in addition to the rails, the chassis 16 comprises a sleeper lifting component 48 positioned on its bottom surface, with the sleeper lifting component 48 holding the sleeper 46 steady whilst the railway-maintenance head 38 performs maintenance on the railway component 14.

[0076] The chassis 16 comprises two tow bars 50, one positioned on the first end 28, seen in Figure 3, and the other positioned on the second end 30, seen in Figure 2. A cable may be attached to these tow bars 50 for scenarios where the railway-maintenance apparatus 10 needs to be transported to hard-to-access locations.

[0077] Referring to Figure 3, the chassis 16 further comprises an emergency tow bar 52 for emergency recovery scenarios, in addition to an electric auxiliary hydraulic pump as a backup drive means. The chassis 16 further comprises a plurality of openings 54 on at least one surface of the railwaymaintenance apparatus 10. The plurality of openings 54 help to cool the power module 22 during operation, thereby helping to prevent overheating of the railway-maintenance apparatus 10. The chassis 16 may further comprises a fan to help with this cooling.

[0078] The chassis 16 comprises a head axle 56 to which the at least one railway-maintenance head 38 is in-use connected to. This head axle 56, similarly to the rail axles 20, comprises a plurality of indexed locations for enabling the position of the at least one railway-maintenance head 38 relative to the chassis 16 to be adjusted based on the gauge WG of the railway 14 being maintained, such that a railway-maintenance tool 40 of the railway-maintenance head 38 is optimally positioned to be engageable with the railway component 14.

[0079] In order to enable the position of the railway-maintenance head 38 to be adjusted, and to allow for different railway-maintenance heads 38 to be engaged with the chassis 16, the railwaymaintenance head 38 is releasably engageable with the chassis 16.The chassis 16 comprises a chassis-hydraulic connector 58 and a chassis-electrical connector 60, with this facilitating hydraulic and electrical connections with the railway-maintenance head. In the depicted embodiment, there is a chassis-hydraulic connector 58 and a chassis-electrical connector 60 on both side portions 32 of the chassis 16, with the purpose of allowing a railway-maintenance head 38 to be connected to the chassis 16 on each side portion 32.

[0080] The railway-maintenance apparatus 10 comprises a programmable logic controller 62 that helps facilitate the autonomous operation of the railway-maintenance apparatus 10. The programmable logic controller 62 uses information collected from a position sensor and a wheel sensor, both sensors being communicable with the programmable logic controller, to generate control instructions. Optionally, the sensors are embedded within the railway-maintenance head 38. For example, on a Vossloh-specific head, the number of turns is counted when releasing the clamp screws to avoid the screws becoming completely detached, and the torque is measured when retightening so that the screw motors can be stopped at the correct torque.

[0081] To begin operation, the operator of the railway-maintenance apparatus 10 applies a user input to the programmable logic controller to manually position the apparatus at a first sleeper 46, the sleepers 46 of the railway 14 acting as reference points for the programmable logic controller 62. Once at the first sleeper 46, the operator actuates the railway-maintenance head 38 to perform maintenance on the railway component 12. This is possible as a user input to the programmable logic controller 62 is able to control all functions of the railway-maintenance apparatus 10, this being a standard requirement for many rail authorities to allow the railway-maintenance apparatus 10 to be controlled in the event of a failure of the programmable logic controller 62.

[0082] Once maintenance has been performed on the first railway component 12, the operator applies another user input to the programmable logic controller 62 to position it at the second sleeper 46, and then subsequently actuates the railway-maintenance head 38 to perform maintenance on the railway component 12.

[0083] The wheel sensor, in the depicted embodiment being a shaft encoder, is utilised by the programmable logic controller 62 to determine a nominal distance between the sleepers 46. This can be done through the railway-maintenance apparatus 10 having a counter that counts the number of pulses from the shaft encoder. The counter is reset to zero every time that the railwaymaintenance head 38 is actuated.

[0084] As the nominal distance is now known the railway-maintenance apparatus 10 is able to operate autonomously, as advantage is made of the fact that the separation between sleepers 46 is commonly found to be consistent, with typical variations from one sleeper 46 to the next being no more than 10mm to 20mm. Each sleeper 46 acts as a reference point for the next sleeper 46, the programmable logic controller 62 determining its position relative to the previous sleeper 46 in order to calculate where the next sleeper 46 is.In order to account for the variations in the separation between adjacent sleepers 46, the programmable logic controller 62 uses a position-sensor output from the position sensor, this being possible due to the programmable logic controller 62 being in communication with the position sensor. The position sensor may, for example, be a wheel that runs along an edge of a foot of the rail 42 such that it is displaced when passing over railway components, the railway components 12 being engaged with the rail 42 at the foot. The programmable logic controller 62 notes the value of the counter when the wheel is displaced, which it then uses to refine the calculated average sleeper separation measurement in order to improve the positioning accuracy of the railwaymaintenance apparatus 10 relative to the sleepers when the railway-maintenance head 38 is actuated. Alternatively, an infrared or similar non-mechanical position sensor could be provided. Based on the position-sensor output, the programmable logic controller 62 generates control instructions for the railway-maintenance apparatus 10, with these control instructions controlling the drive means and consequently the movement of the railway-maintenance apparatus 10. The programmable logic controller 62 is additionally configured to disregard sleeper separation measurements that are unreasonably short due to, for example, the position sensor passing over a stone. The control instructions generated by the programmable logic controller 62 can also be adjusted to compensate for environmental factors, such as low wheel adhesion, which occurs in adverse weather conditions.

[0085] Whilst in the depicted embodiment the position sensor is a wheel, the position sensor could also be one of: an optical sensor; a light sensor; an ultrasound sensor; a level sensor; or any combination thereof. Furthermore, whilst in the depicted embodiment the position sensor is a wheel, in other embodiments not depicted the position sensor is positioned on and / or within the railway-maintenance head 38. Other sensors not utilised for sensing position are also positionable on and / or within the railway-maintenance head 38.

[0086] The chassis 16 further comprises a status sensor which is configured to generate a status-sensor output indicative of a status of the railway component 12, the programmable logic controller 62 being configured to generate control instructions for the railway-maintenance apparatus 10 based on the status-sensor output. The programmable logic controller 62 is able to identify whether maintenance is necessary and, if it is not necessary, it is then able to move on to the next railway component 12, avoiding unnecessary maintenance being performed, which costs both time and money. For example, a status sensor could comprise an optical sensor, such as a live-video feed, which utilises artificial intelligence technology to determine whether a railway component 12 is in need of maintenance or replacement.

[0087] The railway-maintenance apparatus 10 comprises a kill switch which may be used to deactivate the railway-maintenance apparatus 10 immediately in emergency scenarios. The railwaymaintenance apparatus 10 also has a manual mode for manual control, this being achieved using a user input associated with the programmable logic controller 62. Both the user input and the killswitch may be connected to the railway-maintenance apparatus 10 by wired connection or wirelessly. In the depicted embodiment, the kill switch is a radio control unit.

[0088] In the event of a fault occurring with the railway-maintenance apparatus 10, the railwaymaintenance apparatus 10 comprises a remote diagnostic and fault-finding option that may be connected to the programmable logic controller 62 to identify any possible issues.

[0089] In the depicted embodiment, the railway component 12 is manually assembled by the user prior to installation by the railway-maintenance apparatus 10. Additionally, when the railway-maintenance apparatus 10 is removing the railway component 12, the user collects the removed railway component 12 after removal by the railway-maintenance apparatus 10. However, it is envisioned that the railway-maintenance apparatus 10 comprises a clip storage bin for the storage of old railway components 12 and / or new railway components 12.

[0090] Figure 4 shows a railway-maintenance head 38 being engageable with the chassis 16 of the railway-maintenance apparatus 10.

[0091] In the depicted embodiment, the railway component 12 that the railway-maintenance head 38 is configured to engage with is a rail clip. However, in another embodiment not depicted, the railway component 12 is a fishplate, wherein the railway-maintenance head 38 is configured to engage and / or lubricate the fishplate.

[0092] The railway-maintenance head 38 in the depicted embodiment is one of a plurality of railwaymaintenance heads 38 that are provided as part of the railway-maintenance apparatus 10. Each one of the plurality of railway-maintenance heads 38 is selectably engageable with the chassis 16, wherein each one of the railway-maintenance heads 38 has a different railway-maintenance tool 40.

[0093] The railway-maintenance tool 40 of each railway-maintenance head 38 is configured to engage with a railway component 12 of a different type, for example, different types of rail clips. The primary railway components 12 that the railway-maintenance apparatus 10 is envisaged to operate on are rail clips, and specifically elastic rail clips. Examples of rail clips that the railway-maintenance tool 40 may be adapted to engage with include, but are not limited to: Pandrol™ Fastclip FC; Pandrol™ Fastclip FE; Pandrol™ Fastclip FD; Pandrol™ e-Clip; Pandrol™ e+- Clip; Pandrol™ PR Clip; Nabla clip; Schinkasen type 102 fastening; Japanese spring-steel leaf fastening; SKL type clips; Pandrol™ SD system; Deenik clip; Pandrol™ Safelok type clips; Vossloh™ SB 4 VK fastening; or any other Vossloh™ rail clip.

[0094] The railway-maintenance head 38 is operated hydraulically, with the railway-maintenance head 38 having at least one head-hydraulic connector 66, each head-hydraulic connector 66 corresponding to a distinct operative motion and connecting to one chassis-hydraulic connector 58 of the chassis 16 to form a hydraulic connection.In the depicted embodiment, the railway-maintenance apparatus 10 utilises a three-service hydraulic connection, and therefore has three distinctive operative motions. An operative motion of the at least one hydraulic connection may comprise at least one of: a screw operation; a grip operation; a release operation; ora lifting operation. Additionally, a motion could be the operation of the fluid dispenser when the function of the railway-maintenance head 38 is to lubricate the railway component 12. The operative motions available to a railway-maintenance head 38 is dependent on the desired application of the railway-maintenance head 38.

[0095] In-use, the programmable logic controller 62 uses the position-sensor output to determine when it is proximate the railway component 12. Once in position, the programmable logic controller 62 uses the status-sensor output from the status sensor to assess the condition of the railway component 12 and subsequently determines whether maintenance is required. If maintenance is required, the programmable logic controller 62 hydraulically operates the railway-maintenance head 38 using a head-drive means in order to engage or otherwise interact with the railway component 62.

[0096] Each railway-maintenance head 38 also has a head-electrical connector 68, which in the depicted embodiment is a 24-pin electrical connection, visualised in Figure 5. The head-electrical connector 68 allows for data transfer to occur between the railway-maintenance head 38 and the programmable logic controller 62. Information such as the number of turns made in a screwing operative motion is transferred to the programmable logic controller 62, in addition to data such as the torque applied when re-tightening a railway component 12 using a screwing operative motion. A further piece of data transfer that occurs is a binary code sent to the programmable logic controller 62 that enables it to identify which type of railway-maintenance head 38 is engaged with the chassis 16. Using this information, the programmable logic controller 62 is then able to selectively choose the correct code to use forthat type of railway-maintenance head 38. It therefore follows that the programmable logic controller 62 has stored code for each type of railwaymaintenance head 38, thereby allowing for a railway-maintenance head 38 to be immediately operable without external code or software needing to be utilised.

[0097] In Figure 4 the interactive operative motion of the gripping railway-maintenance head 38 is the gripping / release operation of the railway-maintenance tool 40, the railway-maintenance tool 40 comprising a pair of gripping members.

[0098] This is in contrast to Figures 5 and 6, where the operative motion of the screwing railwaymaintenance head 38 is a screwing / unscrewing operation. This screwing operative motion, alongside the hydraulic actuation of the railway-maintenance tool 40, is facilitated by the railwaymaintenance head 38 comprising a spring 70, a spring drive arm 71 and a spring drive motor 72. The spring drive motor 72 is connected to the spring 70 by the spring drive arm 71. When the spring drive motor 72 is applying a torque on the railway component 12, and therefore when the spring drive motor 72 is applying a torque on the railway-maintenance tool 40, the spring drive arm71 moves a distance that is substantially proportional to the torque being applied by the spring drive motor 72.

[0099] The programmable logic controller 62 is able to measure the torque applied by the spring drive motor 72 due to the spring drive arm 71 having a motor-engagement portion that interacts with the spring drive motor 72. In the depicted embodiment, the motor-engagement portion is co-axial with the spring drive motor 72 and comprises gear teeth on its outer edge, the gear teeth engaging with a mating gear on a potentiometer shaft. The resistance of the potentiometer varies with the torque applied by the spring drive motor 72, and consequently can be used by the programmable logic controller 62 to determine the torque being applied. The programmable logic controller 62 can use this information to send signals to the spring drive motor 72, commanding it to either activate or deactivate depending on the operation being performed.

[0100] The spring 70 provides a force on the spring drive arm 71 that enables the maximum appliable torque generated by the spring drive motor 72 to be measurable by the programmable logic controller 62.

[0101] A common feature that is present between the different railway-maintenance heads 38 in both Figure 4 and Figures 5 and 6 is the head-hydraulic connector 66 and the head-electrical connector 68. These connectors are common components as this facilitates the ability of the chassis 16 of the railway-maintenance apparatus 10 to engage with a plurality of railway-maintenance heads 38. A further common feature between the different railway-maintenance heads 38 is a head-axle receiver 73. The head-axle receiver 73 has an aperture 74 that is complementarily formed to a cross-section of the head axle 56 and is for in-use receiving the head axle 56. The railwaymaintenance head 38 can then be securely connected to the head axle 56 by the use of bolts or pins inserted into the indexed locations of the head axle 56. Similarly to the rail axles 20, in a separate embodiment of the railway-maintenance apparatus 10, the indexed locations may be present on a continuous guide rail as opposed to a discrete system.

[0102] For all the railway-maintenance heads 38, the railway-maintenance tool 40 is complementarily formed to the railway component 12 to ensure secure and fixed engagement when maintaining a railway component 12.

[0103] A method of performing a maintenance action on a railway component 12 of the railway 14, using the railway-maintenance apparatus 10, therefore may comprise the steps of: providing a railwaymaintenance apparatus 10 as described; engaging the railway-maintenance tool 40 with the railway component 12; and performing the maintenance action on the railway component 12. A transport vehicle may transport the railway-maintenance apparatus 10 from one location to the next. Alternatively, the railway-maintenance apparatus 10 may be stored in a location that is a part of a railway 14, for example, the railway-maintenance apparatus 10 could move itself along the railway 14 to a railway depot. Another option could be the storage of the railway-maintenanceapparatus 10 off of the railway 14, such as in a warehouse, which is facilitated by the at least one continuous tread 34.

[0104] Looking at the example where the railway-maintenance apparatus 10 is transported by a transport vehicle, the apparatus is transported in the lowered configuration, wherein the wheelset is suspended above the ground and the at least one continuous tread 34 is positioned on the ground. Once at the delivery location, the operator of the railway-maintenance apparatus 10 applies a user input to the programmable logic controller 62 to signal to the railway-maintenance apparatus 10 that it moves off of the transport vehicle. The programmable logic controller 62 then signals to the tread motor to engage, which subsequently moves the railway-maintenance apparatus 10.

[0105] The railway-maintenance apparatus 10 is driven using the at least one continuous tread 34 to a railway 14, where stopping user input is applied to the programmable logic controller 62. A further user input signals to the programmable logic controller 62 that the raised configuration be attained. The programmable logic controller 62 activates the at least one actuator 36 connected to the at least one continuous tread 34, causing the wheelset to descend onto the railway 14, and the at least one continuous tread 34 to thereafter be raised above the railway 14.

[0106] To begin operation, the operator of the railway-maintenance apparatus 10 applies a user input to manually position the apparatus at a first sleeper 46, and then actuates the railway-maintenance head 38 to perform maintenance on the railway component 12 associated with said sleeper 46. Once the maintenance has been performed on the first railway component 12, the operator then applies another user input to position the railway-maintenance apparatus 10 at a second sleeper 46, and then actuates the railway-maintenance head 38 to perform maintenance on the railway component 12 associated with the said sleeper 46. The railway-maintenance apparatus 10 is now operable autonomously.

[0107] An example scenario is when utilising the railway-maintenance apparatus 10 for the removal of old or damaged railway components 12, when the programmable logic controller 62 determines that the railway-maintenance apparatus 10 is positioned at a sleeper 46, it generates a control instruction that initiates the hydraulic action of the railway-maintenance head 38. This is facilitated by the hydraulic connection between the chassis 16 and the railway-maintenance head 38, with the at least one chassis-hydraulic connector44 in-use connected to the at least one head-hydraulic connector 66.

[0108] In the depicted embodiment, the hydraulic connection facilitates three distinctive operative motions. For the railway-maintenance head 38 shown in Figure 4, which comprises a railwaymaintenance tool 40 being complementarily formed to the Pandrol™ Fastclip rail clips, the operative motions include: a grip and release operation; a horizontal operation; and a vertical operation.

[0109] When at the sleeper 46, the programmable logic controller 62 activates the head-drive means to hydraulically actuate the vertical operation, such that it positions the railway-maintenance tool 40at an elevation that enables interaction with the railway component 12. The programmable logic controller 62 is able to determine when this elevation has been attained by being communicable with an alignment sensor positioned on the railway-maintenance head 38.

[0110] The communication between the alignment sensor and the programmable logic controller is facilitated by the in-use electrical connection between the railway-maintenance head 38 and the chassis 16, this occurring through the in-use connection of the head-electrical connector 68 with the chassis-electrical connector 60.

[0111] The programmable logic controller 62 also actuates the horizontal operation, which can occur before or after the vertical operation. This positions the railway-maintenance tool 40 such that interaction with the railway component can occur 12. The programmable logic controller 62 is able to determine that the railway-maintenance tool is in the desired horizontal position using the or a further alignment sensor.

[0112] Following the alignment of the railway-maintenance tool, the programmable logic controller 62 actuates the gripping operation, wherein an engagement sensor may indicate to the programmable logic controller 62 that a secure grip has been achieved, this information being transferred through the electrical connection between the railway-maintenance head 38 and the chassis 16. Subsequently, the other operative motions are actuated to remove the railway component 12, with the release function then actuated to discard the railway component 12.

[0113] When installing new railway components 12, a similar process is used. The operator, however, instead assembles the railway components 12 ahead of the railway-maintenance apparatus 10. Whilst not being in the depicted embodiment, it is envisioned that the railway-maintenance apparatus 10 may be able to individually assemble the railway components 12.

[0114] To cease maintenance, the operator applies a stopping user input to the programmable logic controller 62. Another user input is then applied, indicating to the programmable logic controller 62 to active the at least one hydraulic actuator 36, in order to attain the lowered configuration. User inputs are then used to move the railway-maintenance apparatus 10 to the transport vehicle. Whilst in depicted embodiment user inputs are used for the movement of the railway-maintenance apparatus 10 off the railway 14, it is also envisioned that the railway-maintenance apparatus 10 is able to guide itself to the desired storage location or transport vehicle.

[0115] A further method of changing the railway-maintenance head 38 will now be described. When changing the railway-maintenance head 38, the electrical and hydraulic connections between the railway-maintenance head 38 and the chassis 16 are disconnected. Subsequently, the railwaymaintenance head 38 is disconnected from the head axle 56, allowing for a different railwaymaintenance head 38 with, for example, a different railway-maintenance tool 40 to be connected to the head axle 56. Subsequently, electrical and hydraulic connections are established between the newly installed railway-maintenance head 38 and the chassis 16.The programmable logic controller 62 then identifies which railway-maintenance head 38, and therefore which railway-maintenance tool 40, is engaged with the chassis 16, with data transfer through the electrical connection facilitating this. This enables the programmable logic controller 62 to apply the appropriate code depending on the railway-maintenance tool 40 being used. Whilst the specific embodiment of the railway-maintenance apparatus prepared and tested as being preferred has a drive means in the form of a hydrostatic drive system, similar performance could be achieved using other drive means. For example, a mechanical drive system could be utilised, comprising a gearbox and clutches, however this would not be as smooth and precise at low speeds like the hydrostatic drive means. Another example would be an electric drive system, comprising an electric generator or battery pack powering electric traction motors. A disadvantage of an electric drive means, however, is that it is more expensive than a hydrostatic drive system. Furthermore, whilst the specific embodiment of the railway-maintenance apparatus prepared and tested as being preferred comprises one railway-maintenance tool per railway-maintenance head, similar performance could be attained utilising a railway-maintenance head with a plurality of railway-maintenance tools. A disadvantage of this, however, is that different railway-maintenance tools often require different operative motions, which consequently necessitates a greater number of hydraulic connections, overall leading a heavier, more complex railway-maintenance apparatus which itself would require a greater amount of maintenance.

[0116] Additionally, whilst the specific embodiment of the railway-maintenance apparatus prepared and tested as being preferred comprises two railway-maintenance heads, one positioned on each side portion of the chassis, similar performance could be attained by having a railway-maintenance head on a singular side portion. A disadvantage of this, however, is that maintenance would take significantly longer to complete. Similar performance could also be achieved using a greater number of railway-maintenance heads, for example, two railway-maintenance heads positioned on each side portion, leading to a total of four railway-maintenance heads. The disadvantage of this is that it significantly increases the complexity of the railway-maintenance apparatus, thereby necessitating aa greater amount of maintenance to be conducted on it.

[0117] Moreover, whilst the specific embodiment of the railway-maintenance apparatus prepared and tested as being preferred comprises three hydraulic connections between the chassis and a railway-maintenance head engaged with the chassis, similar performance could be achieved with a railway-maintenance apparatus having a different quantity of hydraulic connections, such as one, two, four, five, six, seven, eight, nine or ten and greater. A disadvantage of having less connections is that it is insufficient for providing the necessary operative motions to maintain a railway component. This could be obviated by using valves within the railway-maintenance head to distribute hydraulic power to perform various different operative motions, however, a disadvantage of this is increased complexity, and therefore a greater chance of reliability issues. A disadvantage of having more connections is that it makes the railway-maintenance apparatus significantly more complicated, leading to a requirement of more maintenance of the apparatus itself to prevent reliability issues.Additionally, whilst the specific embodiment of the railway-maintenance apparatus prepared and tested as being preferred utilises a sleeper as a reference point for determining a position of the chassis and / or railway-maintenance head relative to the sleeper, different methods could be applied to achieve the similar performance. For example, the railway-maintenance apparatus could ascertain its position based on the number of wheel rotations since the last maintenance action was performed. A disadvantage of this, however, would be that it would not function for railways where the sleepers are not consistently spaced.

[0118] Furthermore, whilst the specific embodiment of the railway-maintenance apparatus prepared and tested as being preferred utilises the changing resistance of a potentiometer for the programmable logic controller to determine the torque being applied by the spring drive motor, similar performance could be achieved utilising other means. For example, the pressure being applied to a hydraulic spring drive motor could be measured. Another example would be the use of proprietary torque transducers.

[0119] The above disclosure demonstrates how the provision of a railway-maintenance apparatus for the autonomous maintenance of railway components is achieved, with the features described working collaboratively to supply such an apparatus. The methods through which the said apparatus functions are also described, in addition to a method demonstrating how the replacement of a railway-maintenance head engageable with the railway-maintenance apparatus can occur.

[0120] The words ‘comprises / comprising’ and the words ‘having / including’ when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components, but do not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0121] It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

[0122] The embodiments described above are provided by way of example only, and various changes and modifications will be apparent to persons skilled in the art without departing from the scope of the present invention as defined by the appended claims.

Claims

Claims1. A railway-maintenance apparatus (10) comprising:a chassis (16) having a wheelset configured to move along a railway (14);a railway-maintenance head (38) being in-use connected to the chassis (16), the railway-maintenance head (38) having a railway-maintenance tool (40) for engaging with and performing a maintenance action on a railway component (12) of the railway (14); a position sensor configured to generate a position-sensor output indicative of a position of the chassis (16) and / or railway-maintenance head (38) relative to a reference point of the railway (14); anda programmable logic controller (62) in communication with the position sensor, the programmable logic controller (62) being configured to generate control instructions for the railway-maintenance apparatus (10) based on the position-sensor output.

2. A railway-maintenance apparatus (10) as claimed in claim 1, wherein the programmable logic controller (62) in-use autonomously operates the railway-maintenance apparatus (10).

3. A railway-maintenance apparatus (10) as claimed in claim 1 orclaim 2, wherein the chassis (16) comprises a drive means for driving the wheelset along the railway (14), the control instructions controlling the drive means.

4. A railway-maintenance apparatus (10) as claimed in claim 3, further comprising a power module (22) being releasably engageable with the chassis (16), the power module (22) being operatively connected to the drive means.

5. A railway-maintenance apparatus (10) as claimed in any one of the preceding claims, wherein the railway-maintenance tool (40) is complementarily formed to the railway component (12).

6. A railway-maintenance apparatus (10) as claimed in any one of the preceding claims, wherein the railway-maintenance head (38) is releasably engageable with the chassis (16).

7. A railway-maintenance apparatus (10) as claimed in claim 6, wherein a plurality of railwaymaintenance heads (38) is provided, each one of the plurality of railway-maintenance heads (38) being selectably engageable with the chassis (16), and each one of the plurality of railway-maintenance heads (38) having a different railway-maintenance tool (40).

8. A railway-maintenance apparatus (10) as claimed in any one of the preceding claims, further comprising a status sensor being configured to generate a status-sensor output indicative of a status of the railway component, the programmable logic controller (62)being configured to generate control instructions for the railway-maintenance apparatus (10) based on the status-sensor output.

9. A railway-maintenance apparatus (10) as claimed in claim 8, wherein the status-sensor output is indicative of a maintenance condition of the railway component (12).

10. A railway-maintenance apparatus (10) as claimed in any one of the preceding claims, wherein the railway-maintenance head (38) comprises at least one hydraulic connection, each one of the at least one hydraulic connection having a distinct operative motions.

11. A railway-maintenance apparatus (10) as claimed in any one of the preceding claims, wherein the wheelset is dimensioned to a gauge of the railway (14).

12. A railway-maintenance apparatus (10) as claimed in claim 11, wherein a width of the wheelset is adjustable to be usable with a plurality of railway gauges.

13. A railway-maintenance apparatus (10) as claimed in claim 12, wherein the width is adjustable in a range of 600mm to 2000mm.

14. A railway-maintenance apparatus (10) as claimed in claim 12 or claim 13, wherein the wheelset comprises a plurality of indexed locations corresponding to a plurality of different widths.

15. A railway-maintenance apparatus (10) as claimed in any one of the preceding claims, wherein the chassis (16) includes at least one continuous tread (34) for moving the railwaymaintenance apparatus (10) when not on the railway (14).

16. A railway-maintenance apparatus (10) as claimed in claim 15, wherein the chassis (16) comprises at least one actuator (36) for altering a configuration of the at least one continuous tread (34), the at least one continuous tread (34) being adjustable between a lowered configuration and a raised configuration.

17. A railway-maintenance apparatus (10) as claimed in any one of the preceding claims, further comprising a sleeper lifting component (48).

18. A railway-maintenance apparatus (10) as claimed in any one of the preceding claims, further comprising a user input associated with the programmable logic controller (62) to permit manual control of the railway-maintenance apparatus (10).

19. A railway-maintenance apparatus (10) as claimed in any one of the preceding claims, wherein the railway-maintenance tool (40) is configured to engage with an elastic rail clip.

20. A railway-maintenance apparatus (10) as claimed in claim 19, wherein the railwaymaintenance tool (40) is configured to engage with a rail clip selected from the list of:Pandrol™ Fastclip FC; Pandrol™ Fastclip FE; Pandrol™ Fastclip FD; Pandrol™ e-Clip; Pandrol™ e+- Clip; Pandrol™ PR; Pandrol™ Safelok series; or any Vossloh™ rail clip.

21. A railway-maintenance apparatus (10) as claimed in any one of claims 1 to 18, wherein the railway-maintenance tool (40) is configured to engage with a fishplate.

22. A railway-maintenance apparatus (10) comprising:a chassis (16) having a wheelset configured to move along a railway (14); and a railway-maintenance head (38) being in-use connected to the chassis (16), the railway-maintenance head (38) having a railway-maintenance tool (40) for engaging with and performing a maintenance action on a railway component (12) of the railway (14); wherein the railway-maintenance head (38) is releasably engagable with the chassis (16) to permit selectable interchange of different railway-maintenance heads (38).

23. A railway-maintenance apparatus (10) as claimed in claim 22, wherein a plurality of railway-maintenance heads (38) is provided, each one of the plurality of railwaymaintenance heads (38) being selectably engageable with the chassis (16), and each one of the plurality of railway-maintenance heads (38) having a different railway-maintenance tool (40).

24. A railway-maintenance apparatus (10) as claimed in claim 22 or claim 23, further comprising a position sensor and a programmable logic controller (62), the position sensor configured to generate a position-sensor output indicative of a position of the chassis (16) and / or railway-maintenance head (38) relative to a reference point of the railway, the programmable logic controller (62) in communication with the sensor and being configured to generate control instructions for the railway-maintenance apparatus (10) based on the position-sensor output.

25. A method of performing a maintenance action on a railway component (12) of a railway (14), the method comprising the steps of:a] providing a railway-maintenance apparatus (10) as claimed in any one of the preceding claims;b] engaging the railway-maintenance tool (40) with the railway component (12); andc] performing the maintenance action on the railway component (12).

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