GB2468597A

GB2468597A - Free standing railway signal

Info

Publication number: GB2468597A
Application number: GB1004291A
Authority: GB
Inventors: Barry Thomas Wright
Original assignee: Unipart Rail Ltd
Current assignee: Unipart Rail Ltd
Priority date: 2009-03-13
Filing date: 2010-03-15
Publication date: 2010-09-15
Also published as: GB201004290D0; GB2508313B; GB201004291D0; GB2468769B; GB2468769A; GB201402161D0; GB2508313A

Abstract

A free standing railway signal comprises a signaling unit 10 mounted on a base portion 2 that rests on the ground and stabilizes the signaling unit. The use of such a device ensures that conventional foundations are not required. The base portion preferably weighs at least 200kg and preferably more than 500kg, is made of concrete and has a footprint of at least 0.8m2. In a specific embodiment the base unit is movable and has means for engaging with a transporting vehicle. The signal may further comprise alignment means such as a rotatable plate 5 to permit adjustment of the signal in relation to the base. In a further embodiment a railway signal with an LED light source and localized power is provided. In a yet further embodiment a stackable base is provided having a protruding upper face on one base is mated with a recessed portion on a lower face of another base (Figs 5a&b). In an additional embodiment the base may have ground engaging portions extending from the lower face of the base. A claim is also made to a system and method of alerting a train passing through a restrictive signal by providing an alert signal to the train.

Description

RAILWAY SIGNALS

The present invention relates to railway signals and components of railway signals, such as signalling units.

Railway signals are positioned at various locations alongside a railway track in order to convey information to the train driver, for example as to which junction or route to take.

Railway signals are installed by laying foundations and sinking a post into those foundations. One or more signalling units are then attached to the post.

Each railway signal is fitted with the signalling units that are required for that location.

Each signalling unit is attached (typically bolted) to the post and sighted to face the train driver. Railway signals are also typically fitted with a ladder so that a skilled engineer can access the signalling units, for sighting and maintenance.

On installation of the railway signal, a signalling box is also installed to house various components that communicate with and control the signal. The signalling box is installed on a suitable site in the vicinity of the railway signal.

In a first aspect the present invention provides a railway signal comprising a signalling unit connected to a stabilising base portion, wherein the base portion is adapted to be placed on the ground such that the signalling unit is stabilised by the base portion.

As is clear from the discussion herein, suitably the railway signal is freestanding.

That is, the freestanding railway signal is not fixed to the ground and does not require any other supporting structure. Thus, the base portion provides integral stabilisation to the railway signal.

Suitably the signalling unit is connected to the base portion by a support member, which support member is preferably a post. Preferably the post is an aluminium post.

In embodiments comprising a post, the arrangement is analogous to conventional railway signals except that according to the present invention the stabilising base portion does the same job as the foundations, namely maintaining the post in a vertical position.

Thus, suitably the railway signal includes a post to which the signalling unit and base portion are connected. The signalling unit can be connected to the post in any of the known conventional ways, for example with a bolt.

The post can be connected to the base portion in any suitable way so as to maintain the post in a vertical orientation when the base portion is placed on the ground. Thus in embodiments the stabilising base portion maintains the post in a vertical orientation. In addition, the present inventors have devised particularly advantageous ways of connecting the base portion to the signalling unit and/or post, and these are discussed below.

It follows that the stabilising base portion of the railway signal of the present invention maintains the signalling unit in the correct position, for example by use of a post as discussed above. In this way foundations are not required.

The avoidance of the requirement to lay foundations is advantageous because foundations require significant site preparation, including digging a hole, making the site accessible to heavy vehicles such as a cement lorry, and waiting for the concrete to set before the railway signal can be erected. The railway signal of the present invention does not require foundations. Thus, time and money can be saved by incorporating the stabilising base portion into a railway signal.

Preferably the base portion has a ground-engaging surface, which ground-engaging surface is the surface that is placed on the ground in use. Suitably this is substantially planar, although it may for example include a recess or channel for receiving the forks of a fork-lift truck so that the base portion can be moved easily.

Preferably the base portion has an upper surface, suitably opposite the ground-engaging surface, which upper surface is adapted for connection directly or indirectly (e.g. via a post) to the signalling unit.

Suitably the weight of the base portion is selected based on the windage of the signalling unit and so would depend on the signal configuration (e.g. size of and number of signalling units).

Preferably, the weight of the base portion is at least 200 kg, more preferably at least 500 kg, more preferably at least 750 kg, more preferably at least 850 kg, more preferably at least 950 kg and most preferably about 1000 kg. Whilst there is in principle no upper limit to the weight of the base portion, in practice it is desirable to avoid unnecessary weight and so a maximum weight of 2000kg, preferably 1500 kg and most preferably 1250 kg is preferred.

A base portion of appropriate weight significantly lowers the centre of gravity of the railway signal.

The base portion may be formed from solid material, such as concrete. Alternatively it may be formed from a free-flowing material held in a container, for example sand or water. Preferably, the base portion is made of concrete. Concrete is an inexpensive, durable and strong material. The material is easily set into any desired shape, for example by using a mould. Thus, suitably the base portion comprises a block, preferably a concrete block and more preferably a concrete block weighing at least 100kg.

In embodiments wherein the railway signal comprises a post, the base portion suitably extends from one end of the post. Preferably the base portion is wider and/or deeper than the diameter of the post.

Suitably, the width, depth and height of the base portion are selected so as to provide the desired stabilising effect (e.g. to hold a post upright). In embodiments, the width and depth of the base portion are selected so as to accommodate the moment created by the post and signalling unit.

Typically the width and/or depth is/are at least 0.5 metres, preferably at least 0.8 metres, more preferably at least 0.9 metres, and most preferably about 1 metre or more.

Suitably the width and/or depth is/are less than 3 metres, preferably less than 2 metres, more preferably less than about 1.5 metres, and most preferably less than about 1.3 metres.

A particularly preferred range is 0.5 to 2 metres, more preferably 0.8 to 1.5 metres and most preferably about 0.9 metres to 1.3 metres.

In embodiments the width and depth are substantially the same. For example, the base portion has a substantially square cross-section in a plane parallel to the ground.

Preferably, the height of the base portion is at least 0.5 metres, more preferably at least 0.8 metres, more preferably at least 0.9 metres, and most preferably at least about 1 metre. A suitable upper limit for the height is about 2 metres, preferably no more than 1.5 metres and preferably no more than 1.3 metres. A particularly preferred height is in the range 0.8 to 1.3 metres.

Suitably the depth (taken to be the along the direction extending from the front to the back of the signalling unit, which is typically the direction in which the light output of the signal is directed) is larger than the width. Suitably the depth is at least 10% larger, preferably at least about 20% larger.

In a particularly preferred embodiment, the base portion has a depth of about I metre, a width of about 1.2 metres and a height of about 1 metre.

Preferably the cross sectional area of the ground-engaging portion of the base portion (i.e. the "footprint") is at least 0.25 m2, preferably at least 0.5m2, preferably at least 0.8m2 and most preferably at least 1m2.

Preferably, the base portion has a square or rectangular cross-section in a plane parallel to the ground. Suitably the base portion has a lower portion which has substantially vertical side walls (when the base portion is placed on the ground).

Preferably, the base portion has an upper portion, which upper portion suitably has sloping side walls. This suitably provides a tapered upper portion. Preferably the upper portion is pyramidal, typically being a truncated pyramid.

A shape of this sort maximises stability. If sloping walls are present, they may be easier to handle and install as compared to straight sided blocks. Providing sloping side walls can also make it easier to produce the base portion, particularly if concrete is used.

As is clear from the discussion herein, suitably the base portion is moveable. That is, the base portion, with or without the attached signalling unit, can be moved from one location to another and is not embedded or fixed to the ground. Indeed, if the railway signal needs to repositioned, for example because of a new track layout, the railway signal may be relocated easily. Typically, the base portion is moveable by a fork-lift truck, or other suitable vehicle. As no new foundations are required, the relocation of the railway signal is significantly cheaper than the conventional approach.

Preferably, the base portion is detachably connected to the signalling unit. An arrangement in which the base portion and signalling unit can be detached provides a number of advantages. For example, the base portion may be manufactured separately from the signalling unit and the two components can then be combined at the site of the railway signal. In addition, the signalling unit may be detached from the base portion in the event of relocation of the railway signal. This makes the relocation more convenient as the base portion will typically be heavier than the signalling unit, and so different relocation vehicles may be used for each component.

Typically, the base portion will be more robust, or at least less susceptible to damage, than the signalling unit. Therefore, detaching the signalling unit from the base portion during transport and relocation affords more tailored transport protection for each component.

Furthermore, the detachable connection allows signalling units to be easily replaced, if, for example, the current signalling unit has come to the end of its useful life, the unit is broken, or if a different type of signalling unit is required.

Preferably, the base portion is reversibly connected to the signalling unit. The reversible connection between the base portion and the signalling portion allows convenient disassembly and assembly of the railway signal, for example as part of relocation or transportation.

In preferred arrangements, as discussed above, the railway signal includes a support member (preferably a post) which connects the signalling unit to the base portion. In such arrangements it is particularly preferred that the support member (preferably a post) is connected to the base portion as discussed above with reference to the signalling unit and base portion. Thus, suitably the support member (preferably a post) is reversibly connected to the base portion.

In embodiments, the base portion includes signalling unit connecting means, for example support member connecting means and preferably post connecting means.

The following discussion is made with reference to post connecting means, but applies mutatis mutandis to signalling unit connecting means. Suitably the post connecting means are adapted to reversibly receive the post. The post connecting means are preferably integral with or fixed to the base portion.

In a particularly preferred example, the post connecting means comprises a receptacle for receiving a correspondingly shaped post. Suitably the receptacle is substantially cylindrical, for receiving a cylindrical post.

Preferably, the railway signal comprises alignment means which permits adjustment (i.e. movement) of the signalling unit (and/or the post to which it is suitably attached) with respect to the base portion. Suitably, the alignment means is located between the signalling unit and the base portion. By providing alignment means between the base portion and the signalling unit, the signalling unit may be aligned without moving the base portion. Simplifying alignment in this way is a significant advantage because all signalling units must be sighted correctly as part of their installation on the rail network.

The correct sighting of a railway signal is vital so that a train driver has maximum visibility of the signal. There are strict regulations in the UK, Europe and elsewhere relating to sightings and visibility. The alignment means can provide sighting for the entire signalling unit, without having to sight individual signalling units. For example this can be achieved by aligning the post with respect to the base portion and suitably maintaining the signalling unit and post in a fixed orientation.

Accordingly, an advantage of the alignment means is that there is no need to provide an adjustable connection between the signalling unit and the post. Indeed, preferably the signalling unit is connected to the post so that its orientation with respect to the post is fixed.

More preferably, the alignment means is adapted to fit onto the base portion (and is fitted to the base portion in use). Alternatively, it is integral with the base portion.

This allows easy access to the alignment means, removing the need for an engineer to scale the railway signal to gain access to the signalling unit.

Preferably, the alignment means is an alignment unit. More preferably, the alignment unit comprises a rotatable member, preferably a rotatable plate. Suitably the rotatable member engages with one or more alignment members, which alignment members may be provided on the base portion. Suitable alignment members are elongate members extending from the base portion (e.g. bolts), which alignment members may be integral with or embedded in the base portion. In this way, the alignment unit allows rotation of the signalling unit relative to the base portion so that the signalling unit may orientated correctly.

Preferably, the alignment unit has one or more apertures for receiving part of a base portion or a signalling unit (for example, for receiving one or more alignment members as discussed above). More preferably, the or each aperture defines a guide path for guiding the position of the signalling unit in a limited range of orientations relative to the base portion. Thus, suitably the alignment means permits relative movement between the base portion and signalling unit but the extent of the movement is constrained. The guide path thereby allows convenient orientation of the signalling unit. More preferably, the apertures define circular guide paths for guiding the rotation of the signalling unit. For example, the guide paths can have the shape of an arc of a circle.

Suitably the alignment means is adapted to provide adjustment of the level of the signalling unit with respect to the base portion. In this way, even if the ground on which the base portion is placed is not level, it is possible to achieve a level signalling unit without having to scale the railway signal.

Preferably, the alignment means comprises locking means, for example a locking fixture, for locking the alignment means so that the signalling unit and base portion have a fixed orientation, It is important that when the signalling unit is in the correct orientation that the position is not changed. Therefore, the locking means ensures that the selected orientation is fixed, removing the requirement of an engineer to check the orientation of the railway signal. Suitably the locking means comprises a nut and corresponding threaded portion (e.g. a nut and bolt).

Preferably the base portion includes a connector for connecting the railway signal to a source of electrical power and/or a cable that transmits signal operation information (e.g. relating to the state (on/off) of the signal).

Preferably, the base portion comprises vehicle engaging means adapted to engage with a vehicle suitable for transporting the base portion, either on its own or with the signalling unit to which it is connected to. For example, the vehicle engagement means can be an attachment loop or channel for receiving a lifting part of a vehicle (e.g. the fork of a fork-lift truck). In the case of the engaging means being an attachment loop, the loop may engage with, for example, a crane hook or a rope and pulley. In the case of the engaging means being a channel, preferably the channel is located in a lower portion of the base portion (e.g. in the ground-engaging surface of the base portion) to receive, for example, a fork of a fork-lift truck. The channel may extend across the entire lower portion of the base portion (e.g. across the entire ground-engaging surface) or a substantial portion thereof.

Thus, the loop or channel simplifies movement of the base portion by a suitable vehicle. In this way the base portion of the railway signal may be easily transported and positioned next to the rail track, Further, the base portion may be easily relocated.

Preferably, the railway signal has no ladder attached to it. A ladder may add weight to the upper portion of a railway signal, and may destabilise the railway signal by raising the centre of gravity. In embodiments, no ladder is attached to the railway signal because the railway signal unit only requires sighting once and/or sighting can be achieved without needing access to the signalling unit.

Suitably the signalling unit comprises one or more LED light sources. Thus, preferably the railway signal is an LED railway signal.

Suitably the railway signal is located on the ground. That is, the base portion is resting on the ground. Such an "in-situ" arrangement also comprises a further aspect of the invention. This also applies to the other aspects of the present invention.

In a second aspect, the present invention provides a railway signal comprising a signalling unit connected to a stabilising base portion, the weight of the stabilising base portion being at least 200 kg.

Preferably, the railway signal, and the base portion in particular, is as described herein. That is, the optional features of the other aspects also apply to this aspect.

In a third aspect, the present invention provides a railway signal stabilising base portion as described herein.

In an fourth aspect, the present invention provides a railway signal comprising a signalling unit and post, wherein the weight of the signalling unit and post is no more than 50kg, preferably no more than 30kg, more preferably no more than 25kg.

Suitably, such an arrangement permits the signalling unit and post to be moved by hand, preferably by a single engineer. This can significantly reduce the cost of installing and maintaining a railway signal.

Suitably the post is an aluminium post. Preferably the post is hollow, i.e. tubular.

Suitably the post is cylindrical. Preferably the wall thickness of the post is less than 20mm, preferably less than 15mm, more preferably less than 10 mm, and most preferably less than 8 mm. Suitably the wall thickness is in the range 2 mm to 8mm, preferably 2 mm to 7mm, more preferably 2.5 mm to 6.5 mm.

Suitably the outer diameter of the post is in the range 110 mm to 180 mm, preferably mm to 170 mm, more preferably 130mm to 160 mm, more preferably 140 mm to mm and most preferably 145 mm to 155 mm. A particularly preferred diameter is in the range 150mm to 155 mm. In one embodiment the outer diameter is about 152 mm.

In a fifth aspect, the present invention provides railway signal comprising a signalling unit and post, wherein the weight of the post is no more than 50kg, preferably no more than 30kg, more preferably no more than 25kg.

In a sixth aspect, the present invention provides a use, in a railway signal, of a post weighing less than 50kg, preferably no more than 30kg, and more preferably no more than 25kg and most preferably no more than 15kg.

A further part of the present invention relates to the provision of power to a railway signal, in particular to address the drawback of the conventional use of large runs of cable to deliver power to a railway signal.

In an seventh aspect, the present invention provides a railway signal comprising a signalling unit having an LED light source, and a localised power source for powering the LED light source.

The localised power source means any power source located within 50m of the railway signal, preferably within 20m, more preferably within lOm and most preferably within 5m. Thus the power source is associated with the railway signal, which is a different approach to conventional railway signals wherein the signal is connected to a central power supply network. The provision of a localised power source makes each railway signal self-sufficient.

The localised power source may be connected to the railway signal by cabling.

However, a railway signal with a Iocalised power source removes the need for long runs of power cabling that extend from an electrical grid to each railway signal.

Cabling is expensive, and so there is a large cost saving associated with reducing the amount of cabling required to power railway signals. Furthermore, the cabling connecting the railway signal to the localised power source may be less heavyweight than conventional railway signal cabling. Less heavyweight cabling may be used as the distance that the power needs to be transmitted is reduced. Also, the cabling may be less heavyweight than conventional railway cabling because the power consumption of LED light sources is lower than conventional filament light sources.

Less heavyweight cabling is less expensive, and so further cabling costs are saved by using cabling that is less heavyweight than conventional railway signal cabling.

In particularly preferred arrangements the localised power source is attached directly to or is integral with the railway signal. For example, the power source may be mounted on or in the railway signal. In one embodiment the power source is located on or in a base portion of the railway signal, for example on an exterior surface of the base portion. In embodiments, the power source may be contained in or on an exterior surface of a housing or casing.

Preferably, the localised power source is a solar panel, wind turbine or a battery.

More preferably, the localised power source is a solar panel, most preferably in combination with a battery. The battery may be charged by the solar panel, and when power is not available from the solar panel, power for the signal may be provided by the battery.

Furthermore, railway signals that incorporate LED signals have a lower power requirement, typically less than I Watt. These power requirements may be achieved by a conventional battery (e.g. an array of batteries) or a solar panel, even in climates that have a low number of sunlight hours, such as the UK.

In embodiments, the power source may be contained in or on an exterior surface of a housing or casing. Preferably, the power source is integral with the railway signal, for example housed in or on an exterior surface of a base portion of the railway signal.

Suitably the signal includes signal control means for controlling the status of the signal in response to an input (e.g. an external message or instruction). Preferably the signal control means includes receiver means for receiving information (e.g. via radio transmission) relating to the status and operation of the signal (for example the aspect that should be illuminated). Suitably the control means also includes transmitter means for transmitting information (e.g. via radio transmission) relating to the status of the signal (for example which aspect is currently illuminated). Suitably the receiver means and/or transmitter means is/are a radio receiver and/or radio transmitter. Preferably the signal control means is powered by the localised power source.

In a eighth aspect, the present invention provides a railway signal comprising a signalling unit having an LED light source, and a connector for connection to a localised power source for powering the LED light source. The connector may be a conventional connector for connecting to known power sources.

In a ninth aspect, the present invention provides a railway signal comprising a signalling unit having an LED light source, and a power source for powering the LED, wherein that the power source is integral with the railway signal.

In a tenth aspect, the present invention provides a railway signal comprising a signalling unit having an LED light source, and a power source for powering the LED, the power source being integral with the railway signal, wherein the signalling unit is connected to a stabilising base portion, the base portion being adapted to be placed on the ground such that the signalling unit is stabilised by the base portion.

Preferably the integral power source is located in or on the base portion.

In a eleventh aspect, the present invention provides a railway signal comprising a signalling unit having an LED light source, and a power source for powering the LED, the power source being integral with the railway signal, wherein the signalling unit is connected to a stabilising base portion, the weight of the stabilising base portion being at least 200kg.

Preferably, the weight of the base portion is at least 500kg. Preferably the integral power source is located in or on the base portion.

Whilst the presence of an LED light source is specified in a number of the aspects, it is also envisaged that a railway signal be provided with a localised power source (e.g. an integral power source) in the case where the light source is not necessarily an LED light source. In particular, other light sources that have a low power consumption may be used.

Thus, in a twelfth aspect, the present invention provides a railway signal comprising a signalling unit and a localised power source for powering the signalling unit. Suitably the signalling unit has a power consumption of less than 1 Watt.

A further part of the present invention relates to stabilising base portions having particular features which permit them to be used in a modular fashion.

In a thirteenth aspect, the present invention provides a railway signal having: a signalling unit connected to a stackable stabilising base portion adapted to be placed on the ground such that the signalling unit is stabilised by the base portion, wherein the base portion has a protruding portion on an upper face to which the signalling unit is connected and a recessed portion on a lower face for receiving a protruding portion of a second base portion, such that the base portions are stackable.

In embodiments, base portions that may be stacked to provide a particularly stable base for the railway signal because of the interlocking/engaging function provided by the protruding and recessed portions. This reduces the risk of shippage between stacked base portions.

Not only can the base portions be stacked for convenience when in storage (e.g. when waiting to be used), but more than one base portion can be stacked together when in use with the railway signal. This allows the weight of the stabilising portion of the signal to be varied so that, for example, a user may select a number of bases to form the stabilising portion depending on e.g. the weight, height, centre of gravity and windage of the signalling unit.

Preferably, the railway signal includes two or more stackable base portions, the stackable base portions being stacked together.

Preferably, the stackable base portion comprises signalling unit connection means to connect the stackable base portion to the signalling unit. Preferably, the signalling unit connection means comprises an aperture for receiving a bolt to attach the base portion to the signalling unit (typically via a post). Alternatively or additionally, the signalling unit connection means comprises a bolt integral in the base.

When the railway signal comprises two or more stackable bases, it is preferred that at least one stackable base has signalling unit connection means. Preferably, all the stackable bases have signalling unit connection means.

Suitably all of the optional features associated with the other aspects pertaining to base portions herein also apply to this aspect.

In a fourteenth aspect, the present invention provides a stackable stabilising base portion for use in a railway signal according to the thirteenth aspect, the base portion being adapted to be placed on the ground and to which a railway signalling unit can be attached to stabilise the signalling unit, wherein the base portion has a protruding portion on an upper face, connecting means on the protruding portion for connecting a signalling unit to the base portion, and a recessed portion on a lower face for receiving a protruding portion of a second base portion, such that the base portions are stackable.

The present inventors have found that it may be desirable to reduce the risk of movement of a base portion as described herein relative to the ground, for example, movement by high winds. Also, the present inventors have sought to improve the provision of a level base portion.

In a fifteenth aspect, the present invention provides a railway signal having: a signalling unit connected to a stabilising base portion adapted to be placed on the ground such that the signalling unit is stabilised by the base portion, wherein the base portion has: a body portion; and a plurality of ground-engaging protrusions extending from a ground-facing lower face of the body portion.

Suitably the plurality of ground-engaging protrusions comprise a plurality of teeth, for example formed by a plurality of channels in the lower face.

In a sixteenth aspect, the present invention provides a railway signal stabilising base portion for use in a railway signal according to the fifteenth aspect, the base portion being adapted to be placed on the ground and to which a railway signalling unit can be attached to stabilise the signalling unit, wherein the base portion has: a body portion; connecting means on an upper face of the body portion for connecting a signalling unit to the base portion; and a plurality of ground-engaging protrusions extending from a ground-facing lower face of the body portion.

The present inventors have found that there may be a health and safety risk to signal installation personnel when installing metal railway signal posts in areas with overhead power cables in the vicinity of the installation site.

The present inventors have found that conventional train warning systems use a large amount of power. For example, a conventional early warning system may include an electromagnet that is energised whenever there is a signal on a stop signal. As this frequently occurs, the magnet is energised for long periods of time and a lot of energy is consumed. The present inventors have found a way of reducing the energy used. In particular, the proposal is that the magnet (or other train alerting means) is energised or activated only when a train has passed through the signal.

In a seventeenth aspect, the present invention provides a railway safety system for providing an alert signal to a train when the train has passed through a restrictive railway signal, the system having a signal control means for controlling the railway signal, the signal control means having a signalling transmitter for transmitting a restrictive signalling signal when the railway signal is displaying a restrictive signal, a train sensor for sensing if a train passes through the railway signal, the train sensor having a sensor transmitter for transmitting a sensor signal when a train passes through the signal, train alerting means for providing an alert signal to the train when the train has passed through the restrictive signal, a power source for powering the train alerting means, and a control unit for controlling power from the power source to the train alerting means, the control unit having a control unit switch to reversibly connect the power source to the train alerting means, the control unit switch being controlled by a control unit receiver adapted to receive the restrictive signalling signal and the sensor signal, such that, in use, when a train passes through a restrictive signal, the restrictive signalling signal and the sensor signal are transmitted to and received by the control unit receiver, the control unit receiver closes the control unit switch to connect the power source to the train alerting means and the train alerting means is activated to provide the alert signal to the train.

Thus, in embodiments, the system provides a warning system whereby in use the train alert means is only activated when it is needed, in other words when both the signal is a restrictive signal and the train has actually passed through the signal. In this manner, the train alert means only requires power during the time it is activated, which will be relatively rare. Thus, power consumption is greatly reduced from conventional systems where the alerting means may be energised for long periods of time when it is not required, such as when the train has obeyed the restrictive signal.

A reduction in power consumption reduces the running costs of the train warning system and may be beneficial to the environment.

Signal control mean may be any railway signal component that controls the state of the signal. Examples of such signal control means are described herein.

In particular, the signal control means may be any railway signal component that controls the signal to a restrictive signal.

Preferably, the signal control means is one or more selected from the control means described herein.

The restrictive signal includes, but should not be limited to, a preliminary caution, caution or stop signal. The restrictive signal may also be a speed limiting signal.

The train sensor may be any sensor that can sense that a train has passed through the signal. Such suitable sensors include, but should not be limited to, treadles and camera sensors. Where the sensor is a camera sensor, the sensor may include a speed sensor for sensing the speed of the train.

Preferably, the sensor is a treadle. A treadle gives accurate information about the position of a train on the track. Suitably, the treadle is positioned down track from the signal in order to sense the train after it has passed through the signal.

The train alerting means may be any device the may send an alert to the train, The alert may trigger an audio and/or visual warning signal on the train. Additionally or alternatively, the alert may activate a function on the train, such as enablement of the train brakes to reduce the speed of the train.

In some embodiments, the train alerting means may be an electromagnet to enable the brakes on the train. An electromagnet is particularly preferred if the restrictive signal is a stop, caution or preliminary caution signal.

In other embodiments, the train alerting means may be a wireless transmitter to transmit an alert signal to the train. The alert signal may be received by the train and trigger an audio and/or visual warning. When the restrictive signal is a speed restriction, the warning may be a speed warning to alert a train driver to reduce the speed of the train.

The power source may be an electrical power source. The electrical power source may be an electricity grid or a localised power source.

Preferably, the power source is a localised power source as described herein. Such localised power sources may be one or more batteries, one or more solar panels and/or one or more wind powered electricity generators.

As the power consumption by the train alerting means is relatively low, the power may be generated from a localised power source. Using a localised power source reduces the amount of power cabling required to connect the warning system to an electricity grid. Furthermore, the warning system may operate independently from the rail network.

In a particularly preferred embodiment, the train alerting means is an electromagnet for enabling the train brakes, the sensor is a treadle positioned down track from the signal and the restrictive signal is a stop signal so that when both the train is sensed by the treadle and the signal is a stop signal, the electromagnet is energised to enable the brakes on the train.

Preferably, the railway signal is a railway signal as described herein.

In a eighteenth aspect, the present invention provides a railway safety system for use in a railway safety system according to the seventeenth aspect, the system having a control unit for controlling power from a power source to train alerting means for providing an alert signal to the train when the train has passed through a restrictive railway signal, the control unit having a control unit switch to reversibly connect the power source to the train alerting means, the control unit switch being controlled by a control unit receiver, the control unit receiver being adapted to receive a restrictive signalling signal from the signal control means and a sensor signal from the train sensor, the restrictive signalling signal being transmitted when the signal is a restrictive signal and the sensor signal being transmitted when the train has passed through the railway signal, such that, in use, when the train passes through the restrictive signal, the restrictive signalling signal and the sensor signal are transmitted to and received by the control unit receiver, the control unit receiver closes the control unit switch to connect the power source to the train alerting means and the train alerting means is activated to provide an alert signal to the train.

The preferred features of the seventeenth aspect apply to the control unit of the forty-fourth aspect.

In a nineteenth aspect, the present invention provides a method of alerting a train that has passed through a restrictive signal, the method having the steps of: i) transmitting a restrictive signalling signal from a railway signal control means to a control unit receiver of a control unit when the railway signal is a restrictive signal; ii) transmitting a sensor signal from a train sensor to the control unit when the train sensor senses the train has passed through the railway signal; iii) the control unit receiver receiving the restrictive signalling signal and the sensor signal; and iv) the control unit connecting a train alerting means to a power source, such that the train alerting means is activated to alert the train when both the railway signal is a restrictive signal and the train is sensed by the train sensor.

The preferred features of the seventeenth aspect apply to the method of the forty-fifth aspect.

Any of the above aspects may be combined, as may the optional and preferred features.

In particular, further aspects are provided in respect of railway signals comprising signalling units defined herein and optionally a post (especially an aluminium post or an electrically non-conductive post) and optionally a base portion defined herein, especially a freestanding concrete base portion. In particular, the railway signals, signalling units and signal modules of the present invention are suitably LED railways signals, LED signalling units and LED signal modules. In particular, the railway signals of the present invention suitably include a localised power source as described herein. Preferably the railway signalling units of the present invention include a localised power source as described herein.

Preferably, the railway signalling units and signalling modules comprise light emitting units, preferably LED light emitting units, as described herein.

DETAILED DESCRIPTION

The invention will now be described by way of example only with reference to the accompanying figures in which: Figure 1 shows a front aspect of a railway signal of the present invention; Figure 2 shows a side view of a base portion of the present invention; Figure 3 shows a front aspect of another railway signal of the present invention; Figure 4 shows a front view of a railway signal of the present invention; and Figure 5 shows a perspective view of a single railway signal base portion of and a front view of a number of base portions stacked together.

Figure 1 shows a free standing railway signal 1 placed on the ground. The signal 1 has a base portion 2 and a signalling unit 3 connected by a post 4. The base portion 2 is a concrete block extending from the metal post 4. The signal has a rotatable plate 5 acting as an alignment means, with nut and bolt locking fixtures 6.

The signalling unit 3 has a multi-junction signal module 7 and a single or multi-aspect signal module 8. The signalling unit has a backboard 9 with apertures for exposing the signalling modules 7 and 8. The modules 7 and 8 are within the casing 10.

Fig. 2 shows the base portion 2 of Fig. I resting on the ground. The block is of concrete and around 1 m tall. The block is fitted with bolts 10 adapted to receive the

rotatable plate 5.

Fig. 3 shows of the same general types as that of Fig. 1, namely a free standing railway signal 1 placed on the ground. The signal I has a base portion 2 and a signalling unit 3 connected by a post 4. The base portion 2 is a block extending from the post 4. The signal has a rotatable plate 5 acting as an alignment means with nut and bolt locking fixtures 6.

The signalling unit 3 has a multi-junction signal module 7 and a single or multi-aspect colour signal module 8. The signalling unit has a backboard 9 with apertures for exposing the signalling modules 7 and 8. The signal of Fig. I has a solar panel 15 attached to the exterior surface of the base portion 2. The solar panel provides a localised power source.

Fig 4. shows another free standing railway signal 50 having a signalling unit 52 attached to a support portion 54 and an enclosure 56 for accommodating signal control means 58. The support portion 54 comprises a support member 60 and a freestanding concrete base portion 62.

The signalling unit has a circular backboard 64. The circular backboard 64 may reduce windage. Other signalling units, such as those described herein, may be used. The signalling unit 52 is attached to support member 60 of the support portion 54.

The support member in this embodiment is a post.

Although not shown, in this embodiment, the support member 60 is accommodated in a channel within the enclosure 56.

The enclosure has a panel 66 that may open to form a door so that the signalling control means 58 may be accessed. / The enclosure includes an adjustment plate 68 to adjust the signal 50 relative to the ground. The enclosure 56 is attached to the base portion by four nut and bolt locking fixtures 70 through apertures in the adjustment plate.

The base portion 62 is a stabilising base portion adapted to be placed on the ground.

The base portion 62 has a protruding portion 72 with an upper face to which the enclosure 56 is attached.

Fig 5a shows a stackable base portion 302 according to the present invention. The stackable base portion has a protruding portion 304 with an upper face 306. The upper face has four apertures 308 for receiving nut and bolt locking fixtures 310 thus acting as a signalling unit connection means. A further aperture 312 on the upper face is for receiving wires and cabling from the signal to the rail network.

The stackable base portion 302 has a recess 314 on a lower face for receiving the protruding portion of a second base portion.

Fig. 5b shows four stackable base portions 302 stacked together. The protruding portion 304 of the bottom three stackable base portions are received in the recess 314 of the stackable base portion 302 stacked above the base portion.

Claims

CLAIMS: 1. A free standing railway signal comprising a signalling unit connected to a free standing stabilising base portion, wherein the base portion is adapted to be placed on the ground such that the signalling unit is stabilised by the base portion.
2. The signal according to claim I, wherein the weight of the base portion is at least kg, more preferably at least 500 kg.
3. The signal according to any of the preceding claims, wherein the base portion is made of concrete.
4. The signal according to any one of the preceding claims, wherein the base portion has a footprint area of at least 0.8m2.
5. The signal according to any of the preceding claims, wherein the base portion is moveable.
6. The signal according to any of the preceding claims, wherein, the base portion further comprises a vehicle engaging means adapted to engage with a vehicle suitable for transporting the base portion.
7. The signal according to any of the preceding claims comprising alignment means between the signalling unit and the base portion so as to permit adjustment of the signalling unit with respect to the base portion.
8. The signal according to claim 7, wherein the alignment means is a rotatable member, preferably a rotatable plate.
9. A railway signal comprising a signalling unit having an LED light source, and a localised power source for powering the LED light source.
10. The signal according to claim 9, wherein the localised power source is a solar panel, wind turbine or a battery.
11. The signal according to claim 9 or 10, wherein the localised power source is integral with the railway signal.
12. A railway signal having: a signalling unit connected to a stackable stabilising base portion adapted to be placed on the ground such that the signalling unit is stabilised by the base portion, wherein the base portion has a protruding portion on an upper face to which the signalling unit is connected and a recessed portion on a lower face for receiving a protruding portion of a second base portion, such that the base portions are stackable.
13. A stackable stabilising base portion for use in a railway signal according to claim 12, the base portion being adapted to be placed on the ground and to which a railway signalling unit can be attached to stabilise the signalling unit, wherein the base portion has a protruding portion on an upper face, connecting means on the protruding portion for connecting a signalling unit to the base portion, and a recessed portion on a lower face for receiving a protruding portion of a second base portion, such that the base portions are stackable.
14. A railway signal having: a signalling unit connected to a stabilising base portion adapted to be placed on the ground such that the signalling unit is stabilised by the base portion, wherein the base portion has: a body portion; and a plurality of ground-engaging protrusions extending from a ground-facing lower face of the body portion.
15. A railway signal stabilising base portion for use in a railway signal according to claim 14, the base portion being adapted to be placed on the ground and to which a railway signalling unit can be attached to stabilise the signalling unit, wherein the base portion has: a body portion; connecting means on an upper face of the body portion for connecting a signalling unit to the base portion; and a plurality of ground-engaging protrusions extending from a ground-facing lower face of the body portion.
16. A railway safety system for providing an alert signal to a train when the train has passed through a restrictive railway signal, the system having a signal control means for controlling the railway signal, the signal control means having a signalling transmitter for transmitting a restrictive signalling signal when the railway signal is displaying a restrictive signal, a train sensor for sensing if a train passes through the railway signal, the train sensor having a sensor transmitter for transmitting a sensor signal when a train passes through the signal, train alerting means for providing an alert signal to the train when the train has passed through the restrictive signal, a power source for powering the train alerting means, and a control unit for controlling power from the power source to the train alerting means, the control unit having a control unit switch to reversibly connect the power source to the train alerting means, the control unit switch being controlled by a control unit receiver adapted to receive the restrictive signalling signal and the sensor signal, such that, in use, when a train passes through a restrictive signal, the restrictive signalling signal and the sensor signal are transmitted to and received by the control unit receiver, the control unit receiver closes the control unit switch to connect the power source to the train alerting means and the train alerting means is activated to provide the alert signal to the train.
17. A railway safety system for use in a railway safety system according to claim 16, the system having a control unit for controlling power from a power source to train alerting means for providing an alert signal to the train when the train has passed through a restrictive railway signal, the control unit having a control unit switch to reversibly connect the power source to the train alerting means, the control unit switch being controlled by a control unit receiver, the control unit receiver being adapted to receive a restrictive signalling signal from the signal control means and a sensor signal from the train sensor, the restrictive signalling signal being transmitted when the signal is a restrictive signal and the sensor signal being transmitted when the train has passed through the railway signal, such that, in use, when the train passes through the restrictive signal, the restrictive signalling signal and the sensor signal are transmitted to and received by the control unit receiver, the control unit receiver closes the control unit switch to connect the power source to the train alerting means and the train alerting means is activated to provide an alert signal to the train.
18. A method of alerting a train that has passed through a restrictive signal, the method having the steps of: i) transmitting a restrictive signalling signal from a railway signal control means to a control unit receiver of a control unit when the railway signal is a restrictive signal; ii) transmitting a sensor signal from a train sensor to the control unit when the train sensor senses the train has passed through the railway signal; iii) the control unit receiver receiving the restrictive signalling signal and the sensor signal; and iv) the control unit connecting a train alerting means to a power source, such that the train alerting means is activated to alert the train when both the railway signal is a restrictive signal and the train is sensed by the train sensor.