WO2008061295A1

WO2008061295A1 - Roadway anti-glare screen

Info

Publication number: WO2008061295A1
Application number: PCT/AU2007/001775
Authority: WO
Inventors: Boydan Joseph Mudryk; Garry David Campbell
Original assignee: Delnorth Pty. Ltd.
Priority date: 2006-11-20
Filing date: 2007-11-19
Publication date: 2008-05-29

Abstract

A roadway anti-glare screen (1) comprises a base (2) adapted to be mounted to a roadway barrier and an anti-glare screen body (3) formed of an elastically flexible sheet steel material. The screen body (3) extends longitudinally between a lower body end (4) and an upper body end (5) and transversely extends between opposing body edges (6). The screen body (3) has a first body face (8) and an opposing second body face (9). The lower body end (4) is mounted to the base (2). The screen body (3) is elastically bendable about 90° from an unbent state about a transverse axis (T) to either side of a longitudinal axis (L) of the screen (1). The base (2) has two mounting apertures (13) for receiving fasteners to mount the base (2) to the roadway barrier. The mounting apertures (13) are disposed on opposing sides of the screen body (3). At least one of the mounting apertures (13) is in the form of an elongate slot configured to enable angular displacement of the screen (1) about the longitudinal axis (L).

Description

ROADWAY ANTI-GLARE SCREEN Technical Field

The present invention relates to the field of roadside safety products, and particularly relates to a roadway anti-glare screen.

Background of the Invention

Glare resulting from the headlights of oncoming traffic on the opposing side of a roadway creates a blinding effect on drivers, reducing their ability to clearly see the path of the roadway and any obstacles ahead. To address this problem, roadway anti-glare screens are known to be mounted on inter-lane concrete or guardrail barriers separating opposing sides of a roadway to separate opposing oncoming flows of traffic. Various forms of roadway anti-glare screens are currently available. Various screens are formed of rigid plastics materials which are damaged upon impact from vehicles, and subsequently need to be replaced when impacted. Partly flexible anti-glare screens, typically made from semi-rigid plastics materials or composite fibreglass materials, enable the anti-glare screen to withstand some impact without significant damage. However, these screens are not able to withstand repeated impacts and deteriorate over time due to the weathering effects of ultra-violet radiation. Anti-glare screens are typically spaced along the inter-lane barrier, and have their faces inclined about 20° to 30° from perpendicular to the direction of extension of the roadway. The anti-glare screens are fixed to the inter-lane barrier at a set angle such that the orientation of the anti-glare screen must be set prior to fixing the screen to the barrier. Once the screen has been fixed to the barrier, its orientation cannot be adjusted without removing the barrier and redrilling new fastening points in the barrier. This particularly poses difficulty when installing the anti-glare screens along curved portions of roadway where some adjustment of the orientation of the anti-glare screen is often required after the initial mounting to achieve the desired performance.

Object of the Invention

It is the object of the present invention to substantially overcome or at least ameliorate one or more of the above disadvantages. Summary of the Invention

In a first aspect, the present invention provides a roadway anti-glare screen having a longitudinal axis and a transverse axis transverse to said longitudinal axis, said screen comprising: s a base adapted to be mounted to a roadway barrier; and an anti-glare screen body formed of an elastically flexible sheet steel material, said screen body extending longitudinally between a lower body end and an upper body end and transversely extending between opposing body edges, said screen body having a first body face and an opposing second body face, said lower body end being mounted to saidQ base, said screen body being elastically bendable about 90° from an unbent state about said transverse axis to either side of said longitudinal axis. Typically, said sheet steel material is sheet spring steel.

In a preferred form, said sheet steel material has a thickness of 0.9 mm to 1.5 mm. In a preferred form, said screen body has a transverse width of 150 mm to 350 mms Typically, said screen body has a length of 500 to 1000 mm.

Typically, said screen body comprises a pair of posts arranged in a side-by-side configuration.

Typically, each of said posts has a generally arcuate transverse cross-section providing a concave post face and a convex post face, said posts being arranged such thatQ said first body face comprises said concave post face of one of said posts and said convex post face of the other of said posts.

For roadways where vehicles drive on the left side of the roadway, it is preferred that said posts are configured such that one said convex post face is positioned on the left of each said body face. 5 For roadways where vehicles drives on the right side of the roadway, it is preferred that said posts are configured such that one said convex post face is positioned on the right of each said body face. hi a preferred form, said screen further comprises a clamp connecting said posts adjacent to said upper body end of each said post. 0 Preferably, said clamp comprises two opposing clamp halves, one said clamp half abutting said first body face and the other said clamp half abutting said second body face, said clamp being secured to said posts by way of fasteners each extending through one said clamp half, through one said post, and through the other said clamp half.

In a particularly preferred form, said base has two mounting apertures for receiving₅ fasteners to mount said base to the roadway barrier, said mounting apertures being disposed on opposing sides of said screen body, adjacent said body faces, at least one of said mounting apertures being in the form of an elongate slot configured to enable angular displacement of said screen relative to said longitudinal axis.

Typically, both of said mounting apertures are in the form of elongate slots. Preferably, each said base half is identical.

In a second aspect, the present invention provides a roadway anti-glare screen having a longitudinal axis and a transverse axis transverse to said longitudinal axis, said screen comprising: a base adapted to be mounted to a roadway barrier; and an anti-glare screen body extending longitudinally between a lower body end and an upper body end and transversely extending between opposing body edges, said screen body having a first body face and an opposing second body face, said lower body end being mounted to or integrally formed with said base; wherein said base has two mounting apertures for receiving fasteners to mount said base to the roadway barrier, said mounting apertures being disposed on opposing sides of said screen body, at least one of said mounting apertures being in the form of an elongate slot configured to enable angular displacement of said screen about said longitudinal axis.

Typically, both of said mounting apertures are in the form of elongate slots.

Preferably, each of said elongate slots is curved about said longitudinal axis. In a preferred form, said base comprises two opposing base halves, one said base half abutting said first body face and the other said base half abutting said second body face.

Preferably, said screen body is mounted to said base by way of fasteners each extending through one said base half, through said screen body, and through the other said base half.

Preferably, each said base half is identical.

Brief Description of the Drawings

A preferred embodiment of the present invention will now be described, by way of an example only, with reference to the accompanying drawings wherein: Figure 1 is an isometric view of a roadway anti-glare screen; Figure 2 is a front elevation view of the screen of Figure 1; Figure 3 is a plan view of the screen of Figure 1; Figure 4 is a left side elevation view of the screen of Figure 1; Figure 5 is an isometric view of a roadway anti-glare screen with a reverse screen configuration;

Figure 6 is an isometric view of one base half of the screen of Figure 1;

Figure 7 is a plan view of the base half of Figure 5;

5 Figure 8 is a view of an anti-glare screen installation on a concrete barrier utilising the screen of Figure 1; and

Figure 9 is a view of an anti-glare screen installation on a guardrail barrier utilising the screen of Figure 1. o Detailed Description of the Preferred Embodiments

Referring to Figures 1 to 4 of the accompanying drawings, a roadway anti- glare screen 1 includes a base 2 that is adapted to be mounted to a roadway barrier, such as a concrete barrier or guardrail barrier, and an anti- glare screen body 3. The screen 1 has a longitudinal axis L, and a transverse axis T that extends transverse to the longitudinal axiss L.

The screen body 3 extends longitudinally between a lower body end 4 and an upper body end 5. The screen body 3 extends transversely between opposing side body edges 6, 7. The screen body 3 is formed of an elastically flexible sheet steel material providing a first body face 8, and a second body face 9. In the embodiment depicted, the screen body0 3 comprises a pair of sheet steel posts 10, 10' arranged in a side-by-side configuration. It is also envisaged, however, that the screen body might be in the form of a single broader sheet.

The screen body 3, formed of an elastically flexible sheet steel material, is configured to be elastically bendable about 90° from an unbent state about the transverse₅ axis T to either side of the longitudinal axis L. Accordingly, when the anti-glare screen is mounted on an inter-lane barrier, and either the first body face 8 or second body face 9 is impacted by a vehicle travelling along the roadway, the screen body 3 is able to elastically bend to absorb the impact and recoil to the upright unbent state, remaining serviceable and able to withstand multiple further repeated impacts. The sheet steelo material is also largely unaffected by ultraviolet radiation.

The posts 10, 10' are typically formed of sheet spring steel, preferably having a Rockwell hardness of C40 to C47. One particularly suitable spring steel is high carbon steel C 1075. The sheet steel will typically have a thickness of the order of 0.9 mm to 1.5 mm. Each post will typically have a transverse width of the order of 75 mm to 175 mm,₅ providing a total screen body transverse width between the side edges 6, 7 of the order of 150 mm to 350 mm. Of course, if the screen body 3 is formed as a single sheet of material rather than two side-by-side posts, a sheet width of 150 mm to 350 mm would be appropriate. Depending on the configuration of the roadway barrier, and particularly the width of separation between opposing traffic lanes, however, narrower or broader screen body widths may be appropriate. The screen body typically has a length between the lower body end 4 and the upper body end 5 of the order of 500 mm to 1000 mm. The length of the screen body may be adjusted as desired to suit any particular application. The length in general should be sufficient to shield drivers from the headlight glare from oncoming traffic on the other side of the roadway. The posts 10, lO'each have a substantially arcuate cross-transverse section, here having a radius of 100 mm to 250 mm, typically about 125 mm. The arcuate cross- transverse section of the posts 10, 10' provides each post 10, 10' with a convex post face 11, 11' and an opposing concave post face 12, 12'. The arcuate cross-section enhances the bending performance of the screen body, assisting in providing sufficient rigidity to avoid any significant displacement of the screen body under loads from prevailing winds or the wake of passing vehicles, whilst readily providing for elastic deformation upon impact. The arcuate cross-section also assists in ensuring the screen body 3 springs back to the unbent state after impact.

The posts are here arranged such that they face in opposing directions with the first body face 8 comprising the convex post face 11 of one of the posts 10 and the concave post face 12' of the other post 10'. Accordingly, the second body face 9 comprises the concave post face 12 of the first post 8 and the convex post face 11 ' of the other post 10'. This provides for substantially equal bending performance of the screen body 3 whether the first body face 8 or the second body face 9 is impacted. This arrangement also provides for improved safety if the convex post faces 11, 11 ' are arranged to be adjacent to and face oncoming traffic such that, upon impact from a vehicle, a receding rounded edge is presented to the vehicle rather than a forwardly projecting leading edge as would be the case if a concave face 12, 12' were to be adjacent to and face the oncoming traffic. A similar cross-section is envisaged when the screen body 3 is formed of a single broad sheet.

Accordingly, for roadways where vehicles drive on the left side of the roadway, such as in Australia and the United Kingdom, the posts 10, 10' should be configured such that a convex post face 11, 11 ' is positioned on the left half of each body face 8, 9, as per the posts depicted in Figures 1 to 4. Alternatively, in roadways where vehicles drive on the right side of the roadway, such as in the US and Europe, the posts 10, 10' should be configured such that a convex post face 11, 11 ' is positioned on the right half of each body face 8, 9 as depicted in the alternate configuration of the anti-glare screen 1' in Figure 5.

The posts 10, 10' are typically galvanised for corrosion protection and powder coated. Relatively non-reflective colours such as dark green or beige are typically utilised for the surface powder coating, but specific finishes will typically be dictated by the relevant road authority.

The base 2 has two mounting apertures 13 for receiving fasteners to mount the base 2 to the roadway barrier. The mounting apertures 13 are disposed on opposing sides of the screen body 3, adjacent the first body face 8 and second body face 9 respectively. Both mounting apertures 13 are in the form of elongate slots, so as to enable angular displacement of the anti-glare screen 1 about the longitudinal axis after mounting holes have been drilled into the underlying roadside barrier and fasteners have been received in the mounting apertures 13, prior to the fasteners being fully tightened. Accordingly, the screen may be located in an approximate orientation relative to the direction of extension of the roadway, typically 20° to 30° from perpendicular to the direction of roadway extension, and further adjustment made to the orientation as desired prior to tightening of the fasteners. Also, even after the fasteners have been tightened, if it is found that the orientation of the screen 1 is not optimal, the fasteners may simply be slightly loosened and the screen 1 rotated as required to achieve the desired orientation. This is particularly important on curved portions of roadway where it may be difficult to assess the optimal orientation of the screen I₅ when initially mounting the screen 1. The elongate slots 13 are typically curved, having a centre of curvature at or adjacent the longitudinal axis L to best enable the pivoting about the longitudinal axis L. The elongate slots 13 are here sufficiently long to enable pivoting of the screen through a total angle of about 60°. It is envisaged, however, that one of the mounting apertures may be a cylindrical hole with the other mounting aperture being an elongate slot such that the screen will pivot about a longitudinal axis through the first mounting aperture rather than a longitudinal axis passing through the centre of the screen 1. The configuration of base with two mounting apertures including at least one as an elongate slot is also envisaged to be applied to other non-elastically flexible anti-glare screens, including those where the anti-glare screen is integrally formed with the base.

The base 2 is here formed of two base halves 14, 14', each moulded from a rigid polycarbonate material. With the two posts 10, 10' facing in opposing directions, the base halves 14, 14' are able to be formed as identical halves, thereby resulting in the requirement for a single mould only. One such base half 14 is depicted in Figures 6 and 7. The two base halves 14, 14' each include an upstanding curved flange 15, 15' for abutting the adjacent body face 8, 9. The base halves 14, 14' each have four body mounting apertures 16 extending therethrough. The screen body 3 is mounted to the base

5 2 by passing a fastener 17 through each of the body mounting apertures 16, in one base half 14, through corresponding apertures in the posts 10, 10' located adjacent the lower body end 4, and through corresponding body mounting apertures 16' in the opposing base half 14. Rather than forming the base 2 in two halves 14, 14' the equivalent structure could be formed from a single moulding, with the lower body end 4 being received in ao channel, and the two flanges 15, 15' being joined by a web so as to form the channel. It is also envisaged that the base halves 14 be formed of metal.

The posts 10 are joined towards the upper body end 5 by way of a clamp 18 which is here in the form of two opposing clamp halves 19, 19', moulded from a rigid polycarbonate material. One clamp half 19 abuts the first body face 8 and the other clamps half 19' abuts the second body face 9. The clamp halves 19, 19' each have two clamp mounting apertures 20, 20' extending therethrough. The clamp 18 is secured to the posts 10, 10' by passing a fastener 21 through each of the clamp mounting apertures 20 in one clamp half 18, through a corresponding aperture in each post 10, 10' located adjacent the upper body end 5 and through corresponding clamp mounting apertures 20' in the0 opposing clamp half 19'. The clamp 18 may alternatively be in the form of a metal strap.

Of course, if the screen body 3 is formed of a single sheet of material rather than two posts, the clamp 18 could be readily dispensed with.

Figure 8 depicts a series of anti-glare screens 1 mounted on a concrete roadway barrier 100. The anti-glare screens 1 will typically be mounted about 500 mm to 750 mm5 apart. Here the anti-glare screens 1 are mounted to the upper face of the barrier 100 by way of masonry anchors passing through the apertures 13 in the base 2 of each anti-glare screen 1.

Figure 9 depicts a series of anti-glare screens 1 mounted to a W-beam guard rail barrier 200. The anti-glare screens 1 are mounted to the barrier 200 by fasteners passingo through the apertures 13 in the base 2 of each anti-glare screen and corresponding pre- drilled apertures in the barrier 200. The fasteners utilised may be nut and bolt fasteners, rivets, or any other suitable fastener.

Claims

CLAIMS:

1. A roadway anti-glare screen having a longitudinal axis and a transverse axis transverse to said longitudinal axis, said screen comprising: a base adapted to be mounted to a roadway barrier; and an anti-glare screen body formed of an elastically flexible sheet steel material, said screen body extending longitudinally between a lower body end and an upper body end and transversely extending between opposing body edges, said screen body having a first body face and an opposing second body face, said lower body end being mounted to said base, said screen body being elastically bendable about 90° from an unbent state about said transverse axis to either side of said longitudinal axis.

2. The screen of claim 1, wherein said sheet steel material is sheet spring steel.

3. The screen of claim 1, wherein said sheet steel material has a thickness of 0.9 mm to 1.5 mm.

4. The screen of claim 1 , wherein said screen body has a transverse width of 150 mm to 350 mm.

5. The screen of claim 1, wherein said screen body has a length of 500 to 1000 mm.

6. The screen of claim 1, wherein said screen body comprises a pair of posts arranged in a side-by-side configuration.

7. The screen of claim 6, wherein each of said posts has a generally arcuate transverse cross-section providing a concave post face and a convex post face, said posts being arranged such that said first body face comprises said concave post face of one of said posts and said convex post face of the other of said posts.

8. The screen of claim 7, wherein said screen is configured for roadways where vehicles drive on the left side of the roadway and said posts are configured such that one said convex post face is positioned on the left of each said body face.

9. The screen of claim 7, wherein said screen is configured for roadways where vehicles drives on the right side of the roadway and said posts are configured such that one said convex post face is positioned on the right of each said body face.

5 10. The screen of claim 6, wherein said screen further comprises a clamp connecting said posts adjacent to said upper body end.

11. The screen of claim 10, wherein said clamp comprises two opposing clamp halves, one said clamp half abutting said first body face and the other said clamp halfo abutting said second body face, said clamp being secured to said posts by way of fasteners each extending through one said clamp half, through one said post, and through the other said clamp half.

12. The screen of claim 1, wherein said base has two mounting apertures fors receiving fasteners to mount said base to the roadway barrier, said mounting apertures being disposed on opposing sides of said screen body, adjacent said body faces, at least one of said mounting apertures being in the form of an elongate slot configured to enable angular displacement of said screen relative to said longitudinal axis. o

13. The screen of claim 12, wherein both of said mounting apertures are in the form of elongate slots.

14. The screen of claim 13, wherein each of said elongate slots is curved about said longitudinal axis. 5

15. The screen of claim 1, wherein said base comprises two opposing base halves, one said base half abutting said first body face and the other said base half abutting said second body face. o

16. The screen of claim 15, wherein said screen body is mounted to said base by way of fasteners each extending through one said base half, through said screen body, and through the other said base half.

17. The screen of claim 15, wherein each said base half is identical. 5

18. A roadway anti-glare screen having a longitudinal axis and a transverse axis transverse to said longitudinal axis, said screen comprising: a base adapted to be mounted to a roadway barrier; and an anti-glare screen body extending longitudinally between a lower body end and an 5 upper body end and transversely extending between opposing body edges, said screen body having a first body face and an opposing second body face, said lower body end being mounted to or integrally formed with said base; wherein said base has two mounting apertures for receiving fasteners to mount said base to the roadway barrier, said mounting apertures being disposed on opposing sides of io said screen body, at least one of said mounting apertures being in the form of an elongate slot configured to enable angular displacement of said screen about said longitudinal axis.

19. The screen of claim 18, wherein both of said mounting apertures are in the form of elongate slots.

I₅

20. The screen of claim 19, wherein each of said elongate slots is curved about said longitudinal axis.

21. The screen of claim 18, wherein said base comprises two opposing base 20 halves, one said base half abutting said first body face and the other said base half abutting said second body face.

22. The screen of claim 21, wherein said screen body is mounted to said base by way of fasteners each extending through one said base half, through said screen body, and

25 through the other said base half.

23. The screen of claim 21 , wherein each said base half is identical.