GB2497080A

GB2497080A - Portable electroluminescent retro-reflective traffic crossing lollipop sign

Info

Publication number: GB2497080A
Application number: GB1120376.7A
Authority: GB
Inventors: Andrew Turner
Original assignee: LOLLIPOP PROJECT Ltd
Current assignee: LOLLIPOP PROJECT Ltd
Priority date: 2011-11-25
Filing date: 2011-11-25
Publication date: 2013-06-05
Also published as: GB201120376D0

Abstract

A portable hand-held traffic crossing sign 1 is provided comprising a display portion 2, a handle portion 3, a power Source, and illumination means for illuminating the display portion 2. The display portion 2 comprises a plurality of layers, including, a semi-transparent and retro-reflective front layer 5, and a semi-transparent and retro-reflective rear layer 6. The illumination means comprises at least one electroluminescent sheet layer 7,8 located between the front layer 5 and the rear layer 6 of the display portion. The illumination means may be controlled by a switch such as a tilt switch.

Description

hand-Held Portabk Sign

Field of the Invention

The invention relates to a portable sign; in particular it relates to a hand-held portable sign for controlling the flow of traffic at a pedestrian crossing which includes means for illumirating the sign.

Backgtound to the Invention Hand held signs al-c coliiliionly used at supervised road crossings, especially near schools where a "lollipop stick" sign is frequently carded by a lollipop person to stop traffic at the crossing.

Tihese signs are typically lightweight reflective signs, having a circular sign pot-Hon and an elongate "stick" or handle portion. One disadvantage of traditional lollipop signs is that they may be difficult to see in conditions of poor visibility. A number of improved lollipop stick n'pe signs have been

described in prior art documents.

GB2359654 (Walker) discloses a lollipop sign illuminated by TEDs, powered by a control box and battery in the handle portion of the sign. The lights around the rim, the word STOP'' and the children crossing logo may all flash. An audible warning may also be activated when the lights are on continuously.

GB2067236 (iopley) describes a portable crossing sign \vith a pair of lamps that flash alternately.

Bancrics are inserted in the hollow handle portion. A circuit board and switch are also mounted in the handle porffiai. A sound generating device, such as a bleeper, may also he included to give an audible warn ing.

These prior art lollipop signs have lamps or LEDs inset-ted thi-ough holes on the face of the sign.

Since the TEDs or lamps are not themselves ieflective the effective teflective suiface area of the sign is reduced. This is a problem if the batten; or the LEDs themselves fail since the reflective surface area of the sign is compromised.

It voud he desirable to provide an improved portable hand-held sign for controlling the flow of traffic at a pedestriati ci-ossing.

Summary of the Invention

One aspect of the invention pro\ddes a portable hand-held traffic crossing sign comprising a display portion, a handle portion, a power source and illumination means for illuminating the display portion, wherein the display portion comprises a plurality of layers, including a semi-transparent and retro-refiecrive front layer and a semi-transparent and retro-reflective rear layer, ard wherein the illuntination means comprises at least one electroluminescent slicer layer located between the fiont layer and the rear layer of the display portion.

Preferahly, the illumination means comprises two electroluminescent sheet layers located between the front layer and the rear layer of the display portion.

The display portion comprises a front face and a rear face and both the front face and the rear face are retro-reflectivc. This allows light directed at each face of the display portion of thc sign) he reflected back towards the source of the light.

In one embodiment of the invention the illumination means are controlled hyntcans of a switch.

Advantageously, the sign further compi-ises means for detecting the orientation of the display portion of the sign with respect to the ground. Preferably the means for detecting the orientation of the display portion is a tilt switch. Tn this embodiment of the invention the illumination means may he controlled by means of the tilt switch.

Advatitageously the illumination means are activated when an angle of at-least 45 degrees between the display means and the ground is detected.

Advantageously the illumination means are deactivated when an angle of less than 45 degrees between the display means and the ground is detected.

Thc construction of the portable hand-held traffic crossing sign of the invention provides for full illumination of the sign itself, rather than mounting an at-ray of indhviclual lights on the sign.

Illuminating the sign in this way does not impede the reflective capacity of the sign since none of the reflective surface of thc sign is occupied by lights. If the battery or the electroluminescent sheet layer should Fail then the sign remains as reflective as a standard traffic crossing sign.

Brief Description of the Drawings

In the drawings, which illustrate preferred embodiments of the inveuHon: Figure 1 is a schematic representation of one embodiment of the sign of the invention; Figure 2 ifiustrates a vertical cross-sectional view of the sign of Figure 1 taken perpendhcular to the display portion; Figure 3 illustrates an expanded view of the display portion of the sign of Figure L, showing the different layers making up the chsplay portion; and Figure 4 is a cross-sectional view through an electroluntinescent layer of the display portion of the sign of Figure 1.

Detailed Description of the Preferred Embodiments

As shown in Figure 1, a hand-held pot-table sign I comprises a generally circular display portion 2 and an elongate handle portion 3. In a preferred embodiment, the display portion 2 comprises an inner circular portion 2a in one colour and a surrounding nm portion 2b in another colour. The inner circular portion 2a preferably includes die word "STOP" and an image of children cr ossing.

As shown iii Figures 2 and 3, the display portion 2 of the sign 1 comprises a plurality of layers, including a front layer 5 and a rear layer 6. In the embodiment illustrated the dllsplav portion also comprises two electntiunnnescent sheet layers 7, 8 and a hacking hoard S.All five of these layers are sandwiched together to form the display porHon 2 of the sign. The electroluminescent sheet layers 7, S are situated on either side of the backing board 9, and con figured such that light emanating from each sheet is directed towards the outer fi-ont and rear layers 5, 6 (as illustrated by die arrows in Figure 3).

The front and rear layers 5, 6 are preferably made from a senil-uansparent reflective plastic. This material gives improved light dispersion and reflective pi-opei-ries. Such a material is retro-reflecHve, reflecting light (for example car headlights) shone onto either the front face 15 or the rear face 16 of the display portion 2 back towards the soul-ce of the light. However, such a material also aliows light to pass through it from within, allowing the display portion 2 to he illuminated from its interior.

A colourant or pigment may also be added to the plastic to enhance its reflective propelties and give a luillillous effect.

An electroluminescent sheet S is illustrated in more detail in Figure 4. TIlie electroluminescent sheet S composes a rear electrode 10 and a front electrode 11. The front electrode 11 is made from a conductive transparent film, for example tin doped indium oxide or indium tin oxide (1110).

Sandwiched between the two electrodes there isa layer of electroluminescent material 12. The electroluminescent material 12 glows when a smali current is passed through it. Examples of suitable electroluntinescent materials include phosphorescent materials.

At least one of the electrodes must be transparent (the front electrode 11 in this example) in order to allow the light to escape (as indicated by the arrows in Figure 4).

An alternatitig power supply, or a battery with an inverter is required for providing a constant light in each electroluminescent sheet 7, 8.

The electroluniinescent sheets 7, 8 may he activated by a switch 4, shown in figure 1. The front mci rear layers 5, 6 of the display portion 2 are fabricated from a semi-transparent reflective material which allows light from within the display portion to pass through the display portion, thereby illuminatitig the display portion 2. Since the front and rear faces 15, 16 of tile display portion 2 are also reflective the sign 1 remains highly reflective when it is not being illuminated from within. Tihe sign 1 also includes a power source for providing power to the LED5 8. Preferably the power source is a removable, rechargeable battery pack which could be located in the handle 3. An inverter is also required to convert the DC power of the battery to AC power which is required for providing a constant light in the electrolununescent sheet.

In an alternative embodiment the display portion of rhe sign niay he configured using only one electroluminescent sheet and no central backing hoard. In this embodiment both of the electrodes of the electroluminescent sheet are transparent, allowing light to emanate from liorh surfaces of the electroluminescent sheet.

lollipop patroL workers are trained to use the sign in parficuJar orientations to signal to drivers and pedestrians. When the patrol person is not ready to cross, the sign is held with the display portioti 2 on the ground and the handle portion 3 held vertically above the display portion 2. TIhe sign I can also he held horizontally to form a harrier when a patrol person wants to prevent pedestrians from crossing. When the paol person is ready to ccoss, the sign is held diagonally with the dllsplay portion 2 held towards the road, at an angle of approximately 45 degrees to the road. this indicates that drivers should he prepared to stop. When the patrol person walks into the middle of the road and plants the sign 1 on the ground, in the position shown in Figure 1, all vehicles must stop.

An automatic tilt switch may be used to switch on the electroluminescent sheet layers 7, 8. The tilt switch may be actuated when it detects that the sign 1 is iaised to approximately 45 degrees. the

S

electroluminescent sheets 7, 8 n1>ty he switched off when the lilt switch detects that the sign 1 is turned upside down with display portion 2 towards the ground. The tilt switch woud preferably be located in the handle portion 3 of the sign Alternatively, or in addiHon, the sign I may have a switch that is activated by engagement with the S ground when the sign is in the position shown in Figure 1. The electroluminescent shects 7, 8 may be switched on when this switch is activated by contact with the road.

When activated, the electroluminescent sheets 7, 8 could pro'ide either constant or flashing lights.