Guard board system and apparatus

Abstract

Guard board apparatus consisting of a guard board, 10, fig 1, a bracket to support the board, 12, a packer, 40, fig 6, for elevating the bracket and a joining clip 52, fig 9 to connect adjacent panels together inline. The bracket has a base 14 with means to secure the base to a horizontal surface 30. The bracket also has a triangular support structure extending upwardly from the base. The support structure has a vertically orientated elongate slot 18 to define first 22 and second 24 arms between which a guard board is locatable in use. The first arm may have a generally vertical outer face extending perpendicular from an edge of the base. A top section of the first arm may be formed with a reduced thickness to the section below. An outer side of the second arm may be formed with a continuous angle from a respective edge of the base, opposite to that of the first arm. The outer face of the second arm may be recessed. A support fin may extend between the base and a wall of the second arm. Apertures may be formed in the walls of the first and second arms.

Description

FIELD OF THE INVENTION The present invention relates to a guard board system and its apparatus. More especially, the invention relates to guard board apparatus for use on a railway, particularly for warning the public about the live conductor rail. BACKGROUND The guard board of the present invention is designed for use with a Third Rail DC Railway Electrification System. This system provides a direct current supply for distribution to trains by means of a conductor rail system. The traction current is returned to substations through the running rails. The traction return system is not connected to an earth electrode and is subject to frequent short circuits and short time overloads leading to frequent circuit breaker operations. The system voltage varies between 300V and 1000V and subject to switching surges of 3kV. Consequently, the live conductor rail poses a serious risk of fatality to a member of general public if it is touched. Guard boarding is provided in high-risk areas, particularly where access to the railway line is not overly restricted. The guard boards are generally fixed to railway sleepers using brackets. Current guard board systems have been found to be provide insufficient or, in some cases, no deterrent, to the public. Wooden guard boarding is used, for example. There are numerous issues with using wood. The boards lose strength and are subject to rotting, even after treatment due the environment in which they are utilised. Furthermore, a build-up of grease tends to occur on the tracks due to automatic grease applicators used to prevent wheel wear on sections of curved track. The grease tends to attract numerous contaminants such as rail-grinding particulates which build up on the track over time. These contaminants can potentially be flammable and thus cannot be used in tunnels due to the high fire risks in hot weather. Rail grinding particulates cause the build-up of grease and other contaminants over time, which become flammable. As such, they cannot be used in tunnels. Fixings become loose in both the sleeper bracket and the sleeve which connects the board to the sleeper. The fixings are commonly metallic causing a risk of short circuiting. Boards can warp and exceed gauge tolerance over time. In the event that the fixings fail, causing the boards to become loose, there is a possibility that the boards could be struck by a train. Moreover, wooden boards, which can be over 3 meters in length, are logistically difficult to transport and require at least two personnel to install. They increase in weight once wet and warp if stored for too long. PVC guard boarding is also used. However, these can warp over time and brackets become brittle and break. They also lack the strength required to prevent a person coming into contact with the live conductor rail. Specialist tools are required for removal to allow maintenance. The present invention seeks to provide guard board apparatus that does not does not suffer from the aforementioned disadvantages of known guard board systems. The invention also provides a support bracket, forming part of the guard board apparatus to support a guard board in location adjacent the live rail of a railway line. The invention also provides a guard board, forming part of the guard board apparatus to provide the warning to the public. The invention also provides a joining clip, forming part of the guard board apparatus to join guard boards together to extend the apparatus. All components are non-conductive to remove the possibility of short circuits caused by fixings. All components, have a high fire resistance / Arc proof (BS476 Class 1) and UL94 VO (Halogen Free) fire standard rating. The guard board and fixings have an increased life expectancy compared to wooden and PVC products. All the components of the system are lightweight, thereby reducing a manual handling risk and can be transported and installed or removed by one person. The apparatus can be removed by non-specialised staff for maintenance tasks as it does not require the use of specialist tools, being instead a “drop and lift” design. STATEMENTS OF INVENTION According to a first aspect there is provided a support bracket for a guard board, the bracket comprising a base having means to secure the base to a horizontal surface, a generally triangular support structure extending upwardly from the base, the support structure having a vertically orientated elongate slot to define first and second arms between which a guard board is locatable in use, the slot being closed at one end, the closed end forming a concave wall. Preferably, the first arm has a generally vertical outer face extending perpendicularly from a respective edge of the base. Preferably, a top section of the first arm is formed with a reduced thickness to the section below. Preferably, an outer side of the second arm is formed with a continuous angle from a respective edge of the base, opposite to that of the first arm. Preferably, an outer face of the second arm is recessed. Preferably, a support fin extends between the base and a wall of the second arm. Preferably, the base has at least one aperture located in the recess. Preferably, the wall of recessed area directly above the aperture is inwardly sloping wall. Preferably, apertures are formed in first and second walls. According to a second aspect of the invention, there is provided, guard board apparatus comprising: an elongate panel; and at least one support bracket constructed in accordance with the first aspect. Preferably, the apparatus further comprises a packer member for securement to the underside of the base of the bracket. Preferably, the packer element has opposing edges each having a upwardly extending locking protrusion. Preferably, the base of the bracket has opposing bottom edges each having a recess to receive a respective locking protrusion of the packer member. Preferably, the apparatus further comprises a joining clip for location over and across the ends of two neighbouring boards. Preferably, the clip is U-shaped defining to arms, the inner surface of each arm being corrugated. BRIEF DESCRIPTION OF FIGURES Preferred embodiments of the invention will now be described by way of example only and with reference to the figures, in which: Figure 1 is a perspective view of a guide board forming part of guard board system apparatus in accordance with the invention; Figure 2 is an end view of the board of figure 1; Figure 3 is a perspective view of a support bracket forming part of the guard board apparatus; Figure 4 is a side view of the bracket of figure 2; Figure 5 is a perspective top view of a packer forming part of the guard board apparatus; Figure 6 is a perspective view of the underside of the packer of figure 5; Figure 7 is a perspective view of the guard board apparatus constructed in accordance with the invention; Figure 8 is a perspective view of two guard board apparatus secured together; Figure 9 is a perspective view of a joining clip forming part of the guard board apparatus; and Figure 10 is a side cross section view of the clip of figure 9. DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION The invention provides guard board apparatus for location next to a live conductor rail of a railway line. The apparatus primarily consists of an elongate guard board, support brackets for the guard board to secure it in place adjacent to the live conductor rail, and joining clips to secure the board within the brackets. The apparatus may also include packers to elevate the height of the brackets. A guard board or panel 10 is shown in figure 1. The board 10 has a simple elongate structure and is made from a GRP Pultrusion Iso Polyester / Vinyl Ester Resin). Other suitable materials may be used appropriate for the outside environment in which the board 10 will be used. The material chosen should be weatherproof and resistant to chemicals likely to be found in railway environments, such as ethylene glycol and diesel fuels. The board 10 is formed as, or painted, yellow to provide clear visibility to someone approaching the railway track, and particularly the live conductor rail. The board 10 could be a different colour as long as it provides visibility from a distance to act as a warning to the public passing through the area. As can be seen in figure 2, the board 10 has rounded longitudinal and lateral edges. Typically, a board 10 is approximately 3000mm in length, 200mm in height and 9.5mm in width. In use, a plurality of boards 10 are aligned alongside the live conductor rail in areas where it is possible for public to access. The boards 10 are located on one or both sides of the live conductor rail. The boards 10 are supported upright along a longitudinal edge by support brackets 12. A support bracket 12 suitable for such purpose is shown in figure 3. The bracket 12 is preferably made from a high performance polyamide material such as, for example, that marketed under the brand Akulon Ultraflow K™. Such material exhibits strong rheological, mechanical, thermal and electrical properties. Other suitable materials may be used provided the material exhibits the same or similar properties. The bracket 12 has a generally triangular shape; preferably the profile is that of a right-angled triangle. The bracket 12 has a substantially rectangular base 14 with a support structure 16 extending upwardly from the peripheral edges of the base 14. The triangular shape of the support structure 16 allows for a wider base 14 to provide stability to the bracket 12. The support structure 16 has a downwardly extending slot 18 to define first and second arms 20, 22. The first arm 20 has a generally vertical outer face extending perpendicularly from a respective edge of the base 14. When used in situ, the outside face of the first arm 20 faces away from the live rail and is the “front face” of the bracket 12 when viewed by the public. A top section 24 of the first arm 20 is formed with a reduced thickness to the section below. This allows the top section 24 of the arm 20 to flex when the board 10 is first inserted into the slot 18, without affecting the structural integrity of the arm 20 as a whole. The outer side of the second arm 22 is formed with a continuous angle from the respective edge of the base 14, opposite to that of the first arm 20. When used in situ, the outside face of the second arm 22 faces towards the live conductor rail and is not visible to the public to prevent tampering of the fixing means which are located in the base 14 behind the board 10. The outer face of the second arm 22 is recessed. To this end, a support fin 26 extends between the base 14 and the outer surface of the wall 28 of the second arm 22 to provide reinforcement and strength the wall 28. Apertures 30 are provided in base 14 within the recess to receive fixing means to fix the base 14 to a horizontal surface such as a railway sleeper. The internal diameter of the apertures 30 is reinforced by metallic compression limiters 32. The apertures 30 may have an internal thread to receive a screw rather than, for example, a bolt. The apertures 30 have a diameter of typically between 14mm or 18mm. They may have the same diameter or may have slightly different diameters to accommodate tolerances of the mechanical fixings. The recessed areas directly above the apertures 30 have inwardly sloping walls 34 to increase the free space above the apertures 30 in order install or remove or otherwise access the mechanical fixings. The apertures 30 may also be recessed into the base 14 to protect the fixings when in situ. The slot 18 is open at the top, to receive a board 10 downwardly into the slot 18. The slot 18 has a vertical orientation, the opposing inner faces of first and second arms 20,22 being generally parallel. As can be seen best in figure 4, the slot 18 does not extend along the entire depth of the support structure 16. The closed end of the slot 18 is formed with a concave end wall 36 to accommodate the complimentary shaped profile of the board 10 and to reduce structural forces near the bottom edge of the board 10 in the event that the board receives an impact. The tips of the arms 20, 22 may be formed with an inwardly curved taper and are rounded to avoid sharp edges. Elongate apertures 38 are provide in the walls of both arms 20, 22 to provide visibility of the yellow board 10 from both sides of the bracket 12 when the board 10 is held in the bracket 12. The apertures 38 may or may not be aligned. In a similar way to the concave end wall of the slot 18, the corners of the apertures 38 are rounded to reduce the potential of material failure by avoiding stress focal points caused by sharp corners. Typically, the height of the bracket 12 is approximately 260mm, the width is 130mm and the depth 62mm. The underside of the base 14 also has recessed portions divided by strengthening ribs. In the event that the bracket 12 requires increased height due to the ground level on which it is to be positioned, a packer or extender 40 is provided which is shaped and dimensioned to compliment the base 14 of the bracket 12. A suitable extender 40 is shown in figures 5 and 6. The extender 40 is preferably made from the same polyamide material as the bracket 12. The extender 40 has the same rectangular form and dimensions as the base 14 of the bracket 12, which base 14 is secured on top of the extender 40 in use. Opposing end edges of the extender 40 have upwardly extending locking protrusions 42 which locate, in use, within complimentary shaped recesses 44 formed in opposing bottom edges of the base 14 of the bracket 12 to locate and lock the bracket base 14 onto the extender 40. Similar complimentary shaped recesses 46 are provided in the bottom edges of the extender 40 directly under the locking protrusions 42 to allow two or more extenders 40 to be stacked on each other to elevate the bracket 12 even higher if needed. Fixing apertures 48 extend through the extender 40 which align with the apertures 30 of the base 14 to receive the fixing members therethrough. If one or more extenders 40 are utilised, longer fixings will be required to extend through the bracket base 14, the or each extender 40, and into the surface to which the bracket 12 is to be secured. As can be seen in figure 6, the underside of the extender 40 is recessed to reduce material, the recesses being divided by strengthening ribs 50, in a similar way to the base 14. Figure 7 shows the guard board apparatus in use. The brackets 12 are spaced apart and secured in an upright orientation. In this example, each bracket 12 is located on one extender 40. A board 10 is then placed over the brackets 12 to be received in slots 18 of each bracket 12. The board 10 extends upright along a longitudinal edge, in a horizontal orientation. To extend the length of the apparatus, two boards 10 with their respective brackets 12 are placed in a line, as can be seen in figure 8. In such a configuration, joining clips 52 are provided to connect the ends of each board 10 together. A suitable joining clip 52 is shown in figure 9. The clip 52 is generally U-Shaped to define first and second arms 54, 56, and is made from the same or similar GRP pultrusion material as the board 10 to have the same physical properties required for the environment it is to be used in. The internal surfaces of each arm 54, 56 are corrugated to provide gripping surfaces in order to hold the boards 10, to keep them aligned in the correct location adjacent the live conductor rail and also to prevent the boards 10 from separating in the event of an impact to a board 10 for example caused by a person kicking or tripping over the barrier. As can be seen best in figure 10, the closed end of the channel formed between the two arms 54, 56 has a concave surface 58 to accommodate the curved profile of the top of the boards 10. The arms 52, 54 have some flexibility, the distal ends being slightly biased towards each other to grip opposing surfaces of the board 10. The internal surfaces of the arms 54, 56 have a slight outward taper. Construction of the guard board apparatus will now be described. Firstly, areas of particular concern along the railway line are identified. These are areas accessible to the public (with or without authorisation), and where there is a risk that the live conductor rail could be touched. Brackets 12 are then secured adjacent to and along the stretch of live rail. If required, the brackets 12 are secured to extenders 40 to increase their elevation. One or more lengths of board 10 are pushed downwardly into the bracket slots 18 such that the board extends adjacent to and along the live rail at that location. Where two or more boards 10 are utilised, the adjacent boards 10 are held together by the joining clips 52 pushed down and across the ends of neighbouring boards 10. The guard boards apparatus can be simply disassembled for maintenance, repair, or replacement, by unclipping the joining clips 52, and lifting the boards 10 out of the bracket slots 18.

Claims

1. A support bracket for a guard board, the bracket comprising a base having means to secure the base to a horizontal surface, a generally triangular support structure extending upwardly from the base, the support structure having a vertically orientated5 elongate slot to define first and second arms between which a guard board is locatablein use, the slot being closed at one end, the closed end forming a concave wall, wherein a support fin extends between the base and a wall of an outer side of the second arm.

2. A bracket according to claim 1, wherein the first arm has a generally vertical outer face 10 extending perpendicularly from a respective edge of the base.

3. A bracket according to claim 2, wherein a top section of the first arm is formed with a reduced thickness to the section below.

4. A bracket according to claim 2 or claim 3, wherein an outer side of the second arm is formed with a continuous angle from a respective edge of the base, opposite to that of 15 the first arm.

5. A bracket according to claim 4, wherein an outer face of the second arm is recessed.

6. A bracket according to claim 5, wherein the base has at least one aperture located in the recess.

7. A bracket according to claim 6, wherein the wall of recessed area directly above the 20 aperture is inwardly sloping wall.

8. A bracket according to any preceding claim, wherein apertures are formed in first and second walls.16 07 259. Guard board apparatus comprising:an elongate panel; andat least one support bracket constructed in accordance with any one of claims 1 to 8.5 10. Guard board apparatus according to claim 9, further comprising a packer member forsecurement to the underside of the base of the bracket.

11. Guard board apparatus according to claim 10, wherein the packer element has opposing edges each having an upwardly extending locking protrusion.

12. Guard board apparatus according to claim 11, wherein the base of the bracket has10 opposing bottom edges each having a recess to receive a respective locking protrusionof the packer member.

13. Guard board apparatus according to any one of claims 10 to 12, further comprising a joining clip for location over and across the ends of two neighbouring boards.

14. Guard board apparatus according to claim 13, wherein the clip is U-shaped defining to15 arms, the inner surface of each arm being corrugated.

Images