WO2008126110A1

WO2008126110A1 - A structured element for lateral road signals

Info

Publication number: WO2008126110A1
Application number: PCT/IT2007/000269
Authority: WO
Inventors: Giorgio Corradi
Original assignee: Irc International Reflective Company S.P.A.
Priority date: 2007-04-11
Filing date: 2007-04-11
Publication date: 2008-10-23

Abstract

A structured element for lateral signals, comprises: a support layer (2) which develops a lie plane (SG) and is shaped such as to define a plurality of reliefs (3a, 3b, 3c...) which are parallel and which project with respect to the lie plane (SG) and comprise a first lateral surface (4a, 4b, 4c) and a second lateral surface (5a, 5b, 5c...); a back-reflecting layer (7) associated to the surface of the support layer (2) on a side thereof from which the reliefs (3a, 3b, 3c...) project. The first lateral surfaces (4a, 4b, 4c) of at least some of the reliefs (3a, 3b, 3c...) exhibit inclinations which are different among themselves with reference to base portions (SGa, SGb, SG...) of the lie plane (SG) comprised between the first and second lateral surfaces of each relief.

Description

A Structured Element for Lateral Road Signals

Technical Field

The invention relates to a structured element for lateral signals. The invention relates in particular to lateral signs which are associated to structures projecting upwards located at the edges of roads in order to indicate the presence of the structures to motorists. These structures comprise guard- rails, New Jersey barriers, poles or even trees located in the immediate vicinity of a road. Background Art

Lateral signs of this type generally comprise a structured element formed by a support layer to which a back-reflecting layer is applied. The back-reflecting layer, when struck by a light beam coming from the headlights of a motor vehicle at an appropriate angle of incidence, reflects the light back, evidencing the lateral obstacle.

For signalling structures arranged at the side of the road surface, such as guard-rails, New Jersey barriers, poles and trees, the above-mentioned structured elements are shaped such as to define a plurality of parallel reliefs which project with respect to the surface to be highlighted. These reliefs comprise a first and a second lateral surface which are joined by a top surface. Each structured element is associated to the surface to be evidenced in such a way that the reliefs are approximately vertical and project transversally from the surface to be indicated. At least a lateral surface of the reliefs projecting transversally from the surface to be indicated is therefore facing in the direction of the oncoming vehicle and the light beam projecting from the headlights thereof, so that the angle of incidence of the light beam, or a fraction thereof, on the lateral surface of the reliefs is relatively low. If there are no reliefs the angle of incidence of the light beam projecting from the headlights is very high as the structured elements, especially if applied on guard-rails and New Jersey barriers, would be in an almost parallel position with regard to the direction of the light beam projected from the headlights, and there would be a poor light reflection towards the driver of the vehicle. In structured elements of known type the projecting reliefs are equal, in the sense that the inclination of the lateral surfaces of each relief substantially coincides with the inclination of the lateral surfaces of all the other reliefs. The consequence of this characteristic is that the range of variation of the optimal angle of incidence of the light beam projected from the headlights with respect to the structured element is very narrow. When a vehicle is moving on a tract of straight road flanked on the left by a guard-rail, the light beam projected from the vehicle lights illuminates only a determined length of guard-rail. Internally of this portion only a few reliefs, which are at a certain distance in front of the vehicle, are struck by the light rays which strike the lateral surfaces of the reliefs at a relatively small angle. Consequently only a small fraction of the light beam is effectively reflected towards the driver. The other reliefs, especially those which are in a more lateral position with respect to the vehicle, are struck by more greatly-inclined light rays, which therefore do not effectively reflect the light back towards the driver. The trajectory of the road is therefore poorly traced for the driver, as only a few reliefs reflect the incident light coming from the vehicle headlights effectively.

The aim of the present invention is to provide a structured element for lateral road signs which can effectively reflect the light beams striking the surface thereof at angles of incidence which are variable within a wide range which is greater than the range offered by known-type elements. Disclosure of Invention

Further characteristics and advantages of the invention will better emerge from the detailed description that follows, made with reference to the accompanying figures of the drawings, which are included purely by way of non-limiting example, in which: figure 1 is a schematic representation of a first embodiment of the structured element for lateral signs according to the present invention; figure 2 is a schematic illustration of a second embodiment of the structured element for vertical signals of the present invention; figure 3 is a schematic representation of how a light beam projected from a light strikes the structured element of figure 1.

With reference to the figures of the drawings, the structured element 1 for lateral signs of the present invention comprises a support layer 2 which develops overall along a lie plane SG and is shaped in order to define a plurality of reliefs 3a, 3b, 3c... which develop parallel to one another and project with respect to the lie plane SG. The reliefs, which in transversal section exhibit an approximately trapezoid outline, comprise a first 4a, 4b, 4c... and a second 5a, 5b, 5c... lateral surface which are joined by a top surface 6a, 6b, 6c ... Base portions SGa, SGb, SGc, of the lie plane SG, comprised between the two lateral surfaces, ideally close the trapezoid edge of the reliefs, defining the larger base thereof. For each relief, a median plane PMa, PMb, PMc... can be defined, passing through the half-way lines of the base portions.

The support layer 2 is preferably made of soft aluminium. This material offers a relatively high resistance in combination with high malleability. In particular, thanks to its malleability, even in the case of a fracture, with the formation of projecting edges, the aluminium offers excellent safety characteristics as it tends in any case to be crushed by the pressure of tyres, reducing the risk of damaging the tyres. The support layer 2 is made of a material exhibiting a certain degree of flexibility and is represented in a flat configuration in which the lie plane SG is also flat. In any case the technical characteristics of the element 1 do not change if the lie plane SG is differently conformed.

A back-reflecting layer 7 is associated to the surface of the support layer 2 on the side thereof from which the reliefs 3a, 3b, 3c... project, with the back- reflecting surface obviously facing towards the outside. The back-reflecting layer. 7 is preferably, of a type having a micro-prismatic, structure. The connection of the back-reflecting layer 7 to the support layer 2 is obtainable by a gluing process using a self-polymerising solvent-free polyurethane resin. The support layer 2 is first spread with a layer of primer, on which thereafter a layer of solvent-free polyurethane resin is applied. The back-reflecting layer 7 is then applied to the layer of solvent-free polyurethane resin. When the polyurethane resin completes polymerisation the support layer 2 is solidly constrained to the back-reflecting layer 7. Following the polymerisation of the first layer of polyurethane resin, the reliefs can be impressed on the support layer 2 by running the support layer, with the back- reflecting layer attached, between a pair of cylinders. A first of these cylinders bears (in relief) the projecting shape of the reliefs, while the other cylinder affords a series of recesses which negatively reproduce the shape of the reliefs. The two cylinders roll without dragging on each other and are arranged with an interaxis which is such that in the zone of minimum distance between the surfaces of the two rollers, through which the support layer 2 and the back-reflecting layer 7 transit, each positive relief is at least partially arranged internally of a corresponding recess.

The first lateral surfaces 4a, 4b, 4c... of at least some of the reliefs 3a, 3b, 3c... exhibit inclinations, being the angle comprised between each of them and the relative base portion SGa, SGb, SGc... which are different. In this way, by specially selecting the inclination of the first lateral surfaces 4a, 4b, 4c..., the reliefs 3a, 3b, 3c..., it is possible to increase the number of reliefs which effectively back-reflect the light which strikes them coming from the headlights of a vehicle. In order better to comprehend this advantage of the invention, reference is made to a first embodiment thereof, illustrated in figures 1 and 3. In this embodiment the reliefs.3_a, 3b, 3c... are arranged in an ordered succession 30 in which,- with reference to the base portions SGa, SGb, SGc, the first surfaces 4a, 4b, 4c..., exhibit progressively different inclinations, while the second surfaces 5a, 5b, 5c, exhibit a same inclination. With reference to figure 3, supposing that the first surfaces 4a, 4b, 4c are facing towards the direction DL in which the light beam of the vehicle originates, the inclination of the first lateral surfaces 4a, 4b, 4c... diminishes in opposition to the direction DL. In other words, within each ordered succession 30, the inclination of the first lateral surfaces 4a, 4b, 4c... diminishes as the source of the light beam gets nearer. This produces a particularly advantageous technical effect. As the light beam projected by the headlights of a motor vehicle, if seen in plan view, is substantially conical and exhibits relatively divergent lateral fractions which illuminate zones arranged laterally with respect to the vehicle, internally of each ordered succession the reliefs that are more distant from the vehicle, i.e. those which have the first lateral surface more inclined than the lie plane SG, back-reflect the less-divergent fractions of the light beam, while the reliefs that are progressively closer to the vehicle, i.e. those exhibiting the first lateral surface less and less inclined with respect to the lie plane SG, back-reflect the more divergent fraction of the light beams (which are poorly reflected by the more inclined first surface). In this way, for a given position of the vehicle, the number of reliefs which effectively back-reflect the light beam coming from the vehicle increases considerably with respect to a solution in which the reliefs are equal. In a second embodiment, illustrated in figure 2, the ordered successions 30 are alternated with opposite ordered successions 31 formed by reliefs 3 a, 3b, 3c, each of which is symmetrical with reference to a median plane thereof PMa, PMb, PMc, with respect to a corresponding relief 3a, 3b, 3c... of an ordered succession 3.0. Also in the opposite ordered successions 3I₅ the. first surfaces 4a, 4b, 4c of the reliefs 3a, 3b, 3c... exhibit -a progressively- different inclination, but the inclinations are opposite with respect to the inclinations of the reliefs belonging to the ordered successions 30. In other words, in the second embodiment, which is also the preferred embodiment, each ordered succession 30 comprises a first relief 3a, a second relief 3b and a third relief 3c. The inclination of the first surface 4a, 4b, 4c diminishes going from the first relief 3a to the third relief 3c. An opposite ordered succession 31 is arranged consecutively to the ordered succession 30, which opposite ordered succession 31 comprises a first relief 3 a which is symmetrical with respect to the first relief 3a of the ordered succession 30, a second relief 3b, symmetrical with respect to the second relief 3b of the ordered succession 30, and a third relief 3c, symmetrical with respect to the third relief 3c of the ordered succession 30. In the second embodiment, the technical effect of the first embodiment of the invention (described above) is reproduced even if the originating direction of the light beam is opposite with respect to the origin indicated in figure 3. If the direction of origin of the light beam is the one indicated in figure 3, the technical effect is due to the ordered succession 30, while if the direction of origin of the light beam is opposite, the technical effect is due to the opposite ordered successions 31. The reliefs illustrated in the two above-described embodiments are asymmetrical with reference to the median planes PMa, PMb, PMc... In a further embodiment of the invention, not illustrated, the reliefs 3a, 3b, 3c. are symmetrical with respect to their own median planes PMa, PMb, PMc, ... and the inclinations of the lateral surfaces of the reliefs are different to one another. The reliefs in this embodiment can be arranged in ordered successions in which the inclinations of the lateral surfaces progressively vary. This solution represents the sum of the two preceding solutions. The structured element is effective in both directions of origin of the light beam and the ordered successions are equal to one another, offering an effective reflection over a long tract of the structured element. In all the described embodiments, it is preferable though not indispensable to interposition the smaller reliefs 13a, 13b, 13c... between the reliefs 3a, 3b, 3c... The smaller reliefs in particular exhibit a smaller height than the reliefs 3a, 3b, 3c... and are symmetrical with respect to their own median planes PMa, PMb, PMc... The height of the smaller reliefs is preferably about 6mm, whereas the height of the reliefs 3a, 3b, 3c... is about 10mm.

With special reference to the embodiments illustrated in figures 1 and 2, the reliefs 3 a, 3b, 3 c exhibit three main and distinct forms which offer a very satisfactory overall illumination of the structured element. A first form, relating to a first relief 3a, exhibits a base portion SGa about 10.5mm long. The projections of the first surface 4a and the second surface 5a on the base portions SGa are respectively about 5mm and 2.5mm. A second form, relating to a second relief 3b, exhibits a base portion SGb which is about 13mm long. The projections of the first surface 4b and the second surface 5b on the base portion SGb are respectively about 7.5mm and 2.5mm. A third form, relating to a third relief 3c, exhibits a base portion SGc of about 15.5mm in length. The projection of the first surface 4c and the second surface 5c on the base portion SGc are respectively about 10mm and 2.5mm. The projections of the second lateral surfaces 5a, 5b, 5c in the three forms realising the reliefs are therefore equal. As for the smaller reliefs 13a, 13b, 13c, these are equal to one another in shape and size. Each base portion SGa, SGb, SGc exhibits a length of about 10mm. The projections of the first surface and the second surface on each base portion are about 3mm.

To increase the resistance _ of .the structured element the support layer 2 is. folded longitudinally along the edges thereof in order to define two folds 2a, 2b, illustrated in figure 1, which at least partially superpose on the back- reflecting layer 7. This further increases the stability and duration of the connection between the back-reflecting layer 7 and the support layer 2 as possibly detachments of the back-reflecting layer 7 along the edges thereof are prevented. As a further reinforcement for the structured element, at the end portions of the structured element itself two C-shaped reinforcement elements 2c, 2d can be provided for preventing any detachments of the two layers 2 and 7 at end portions thereof. The two reinforcement elements 2c, 2d could also be constituted by two folds of end portions of the support layer 2, folded over themselves and superposing on ends of the back-reflecting layer 7. The reinforcement elements 2c, 2d can be provided with holes for connection thereof to a support surface.

To facilitate the application and fastening of the structured element to a surface, in particular to an irregular surface, such as a tree, a flat layer 10, preferably made of soft aluminium, can be associated to the support layer 2 below the reliefs 3a, 3b, 3c... , and be arranged on the lie plane SG. The flat layer 10 can be associated to the support layer 2 by means of a coat of self- polymerising adhesive or mechanical elements such as screws or rivets. The presence of the flat layer is useful for fixing the structured element to an irregular surface because it increases the rest surface of the structured element. The flat layer 10 is especially recommended for application of the element to a tree trunk. For this purpose two or more elastic elements can be fixed to opposite edges of the flat layer 10. Flexible elements, such as string or bands or the like, can be wound about the tree trunk and fixed to the elastic elements in such a way as to associate the structured element to the trunk. The presence of the elastic elements means that the forces produced by the natural growth of the tree trunk can be absorbed without causing the structured element to detach and without deforming the support layer 2. The tension caused by the growth of the tree is absorbed by the flat layer 10.

Claims

Claims.

1). A structured element for lateral signals, comprising: a support layer (2) which develops a lie plane (SG) and is shaped such as to define a plurality of reliefs (3a, 3b, 3c...) which are parallel and which project with respect to the lie plane (SG) and comprise a first lateral surface (4a, 4b,

4c) and a second lateral surface (5a, 5b, 5c...); a back-reflecting layer (7) associated to the surface of the support layer (2) on a side thereof from which the reliefs (3a, 3b, 3c...) project; characterised in that the first lateral surfaces (4a, 4b, 4c) of at least some of the reliefs (3a, 3b, 3c .) exhibit inclinations which are different among themselves with reference to base portions (SGa, SGb, SGc .) of the lie plane (SG) comprised between the first and second lateral surfaces of each relief.

2). The structured element of claim 1, wherein at least some of the reliefs (3a,

3b, 3c,) are arranged in ordered successions (30) in which the first surfaces

(4a, 4b, 4c) exhibit progressively different inclinations with respect to the- base portions (SGa, SGb, SGc...).

3). The structured element of claim 2, wherein the ordered successions (30) are alternated with opposite ordered successions (31) formed by reliefs (3a,

3b, 3c) each of which is symmetrical with a corresponding relief (3a, 3b,

3c .) of an ordered succession (30), with reference to a median plane

(PMa₅PMb₅PMc.) thereof.

4). The structured element of claim 3, wherein: each ordered succession (30) comprises a first relief (3a), a second relief (3b) and a third relief (3c); the inclination of the first surface (4a, 4b, 4c) of the reliefs diminishes in order going from the first relief (3a) to the third relief (3c); an opposite ordered succession (31) is arranged consecutively to each ordered succession (30), which opposite ordered succession (31) comprises a first relief (3a), symmetrical with respect to the first relief (3a) of the ordered succession (30), a second relief (3b), symmetrical with respect to the second relief (3b) of the ordered succession (30), and a third relief (3c), symmetrical with respect to the third relief (3 c) of the ordered succession (30).

5). The structured element of claim 1, wherein the reliefs (3a, 3b, 3c .) are symmetrical with respect to the median planes thereof (PMa₅PMb₅PMc...), and the inclinations of the lateral surfaces of the reliefs are different with respect to base portions (SGa, SGb, SGc.) of the lie plane (SG) comprised between the laterals surfaces of each relief.

6). The structured element of at least one of the preceding claims, wherein smaller reliefs (13a, 13b, 13c .) are interposed between the reliefs (3a, 3b, 3c..)₅ the smaller reliefs being of a smaller height than the reliefs (3a, 3b, 3c.) and being symmetrical with respect to median planes thereof (PMa, PMb₅PMc...).

7). The structured element of claims 4 and 6, wherein the reliefs (3a, 3b, 3c .) exhibit three distinct main forms; a first form, of a first relief (3a), exhibits a base portion (SGa) being about 12.5mm in length; the projections of the first surface (4a) and the second surface (5a) on the base portion (SGa) are respectively of about 5mm and 2.5mm; a second form, of a second relief (3b), exhibits a base portion (SGb) being about 13mm in length; the projections of the first surface (4b) and the second surface (5b) on the base portion (SGa) are respectively about 7.5 and 2.5mm; a third form, of a third relief (3c), exhibits a base portion (SGb) being about 15.5mm in length; the projections of the first surface (4c) and the second surface (5c) on the base portion (SGc) are respectively about 10mm and 2.5mm. 8). The structured element of claim 6, wherein the smaller reliefs (13a, 13b, 13c .) exhibit base portions (SGa, SGb, SGc) which are about 10mm long, the projections of the first and second surfaces on each base portion being about 3mm.

9). The structured element of at least one of the preceding claims, wherein the support layer (2) is made of soft aluminium.

10). The structured element of at least one of the preceding claims, wherein the support layer (2) is folded longitudinally along edges thereof in order to define two folds (2a, 2b) which at least partially superpose on the back- reflecting layer (7).

11). The structured element of at least one of the preceding claims, wherein two reinforcement elements (2c, 2d) are located at end portions of the structured element, which two reinforcement elements (2c, 2d) press the support layer (2) and the back-reflecting layer (7) towards one another. 12). The structured element of at least one of the preceding claims, wherein a flat layer (10) is associated to the support layer (2) below the reliefs (3 a, 3b, 3c.) in such a way as to be arranged on the lie plane (SG). 13). A process for realising a structured element as in at least one of the preceding claims, comprising following stages: arranging the support layer (2); spreading a coat of primer on the support layer (2); spreading a coat of solvent-free polyurethane resin on the layer of primer; applying the back- reflecting layer (3) on the layer of polyurethane resin.

14). The process of claim 13, wherein following application of the back- reflecting layer (7), the polyurethane resin is left to polymerise completely; and following polymerisation the support layer (2) is subjected to a stage of plastic deformation in order to define the reliefs (3a, 3b, 3c).