GB2335526A

GB2335526A - Ice danger indicator

Info

Publication number: GB2335526A
Application number: GB9805879A
Authority: GB
Inventors: Brian Thomas King
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-03-20
Filing date: 1998-03-20
Publication date: 1999-09-22
Also published as: GB9805879D0

Abstract

An ice warning indicator wherein a reflector (12) is partially covered by a pocket (14) containing a chemical such as ethyl sebasate which changes transparency in the region of an ice-forming temperature, whereby to change the visual appearance of the reflector. The indicator may take the form of a round reflector which becomes partially obscured to show a triangular shape as the temperature lowers. Alternatively, the indicator may include differently colored reflectors and different chemicals to form a graduated indicator (Figure 6). The indicator may be included in catseye studs or in an airport runway guide light.

Description

2335526 Ice Dan= Indicator This invention relates to a device for

indicating the danger of ice in the vicinity of the device.

This ice danger indicator has a wide variety of possible uses, including at road edges, road surfaces, possibly when incorporated in catseyes, airport runways, public and private footways, boats and offshore platforms, etc.

According to the invention, there is provided an ice danger indicator comprising a reflector at least in part covered by one or more pockets containing a chemical exhibiting a change in transparency at a predetermined temperature at which ice may form in the vicinity, whereby to change the visual appearance of the reflector.

Preferably, the chemical is such that it is fully transparent above the predetermined temperature but becomes at least partially opaque, for example due to solidification on freezing, at and below the predetermined temperature.

The chemical, in general a liquid at least when warent is preferably selected to change transparency at a predetermined temperature between -2 and +5 degrees C, more preferably 0 and 4 degrees C, and most preferably 1 and 3 degrees C. A preferred chemical is oil or water based.

One suitable chemical is ethyl sebasate, which changes from a transparent liquid to a somewhat opaque solid at 2 degrees C.

The pocket or pockets in which the chemical is incorporated may be suitably shaped so that the shape of the reflector is visually changed when the environmental temperature falls below the predetermined temperature. For example, the pocket or pockets may be so shaped that the leners ICE are revealed at and below the predetermined temperature. Alternatively, a normally round reflector could become partially obscured to show a triangular shape at and below the critical temperature. Many other analogous variations are possible.

It is also practicable, by the incorporation of differently coloured reflectors in the same indicator, and by use of different chemicals in association with the different reflectors, to indicate two or more predetermined temperatures, such as 4 degrees C, 3 degrees C and 1 degree C. In general, therefore, it is also possible to provide a graduated indicator.

A preferred construction of indicator is a reflecting layer and a lens, and one or more chemical containing pockets between the reflector and the lens. The pocket or pockets may be formed as one or more recesses in the reflector or the lens, preferably the former.

The invention is further described with respect to some examples, making reference to the accompanying drawings, in which:- Figure 1 shows one possible form of indicator when operative; Figure 2 shows the construction of the indicator of Figure 1; Figures 3 and 4 show modified indicators; Figures 5 and 6 show examples of graded indicator; Figures 7a and 7b show possible embodiments of catseye incorporating the indicator; i 1 Figure 8 shows another embodiment of ground stud incorporating the indicator; and Figure 9 shows an embodiment for use at airport runways.

Referring to Figure 1, the indicator when operative, for example on a verge post at the side of a road, but convenient for use in an environmental situation where an ice warning may be desirable, displays the word ICE.

This is achieved by the construction shown in Figure 2. This construction of indicator comprises a lens 10, a coloured reflector 12, and sandwiched between the two a chemical containing pocket 14 from which the word ICE is cut out, i.e. the pocket covers the whole area of the indicator except for the letters ICE. A convenient chemical is ethyl sebasate.

In use, at temperatures above 2 degrees C, the whole area of coloured reflector is visible by light reflected from it, due to complete transparency of the liquid ethyl sebasate. However, at and below 2 degrees C, this chemical substantially solidifies and becomes generally opaque, thereby obscuring the reflector except for the letters ICE, so that only this warning is visible by reflected light.

Figure 3 shows a modification in which the word ICE appears horizontally instead of vertically, and Figure 4 shows an example wherein the word ICE is replaced by a warning triangle.

Figure 5 shows that, by use of three transparent chemicals which become opaque respectively at 4 degrees C, 2 degrees C and 1 degree C, a graded indicator can be produced, wherein the letters ICE are revealed in steps as the temperature falls towards freezing point.

Figure 6 shows that the same type of graded warning can be achieved using three separate reflectors, which may be of different colours, andlor of different shapes.

Figures 7a and 7b show that the indicator may also be incorporated into catseye studs, located between the two reflecting eyes.

Figure 8 shows an indicator embodying a series of mini-reflectors, chemicalcontaining pockets and lenses.

Finally, Figure 9 shows that the indicator may be incorporated in an airport runway guide light.

A possible modification, for example to the construction of Figure 2, is to use individual chemical-containing pockets for the respective letters, or even a modular construction of indicator in which each letter is self contained, with its own reflector, lens and chemical-containing pocket betwen them.

- 1 In all instances, the indicator aims to produce a visual change in appearanCe in reflected light when the temperature drops to a level close to freezing point, by concealing part of the whole area of one or more reflectors visible at higher temperatures.

As previously mentioned, the indicator has a wide range of fields of use, not only for road users but also for pedestrians, boat users and many others.

The indicator in accordance with the invention has substantial advantages over cholesteric crystal based devices, being robust and not liable to deteriorate in UN fight. It is not affected by extreme temperatures, requires minimal maintenance, and is emily detectable at a distance.

Claims

1. An ice danger indicator comprising a reflector at least in part covered by one or more pockets containing a chemical exhibiting a change in transparency at a predetermined temperature at which ice may form in the vicinity, whereby to change the visual appearance of the reflector.

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2. An indicator according to claim 1, wherein the chemical is such that it is fully transparent above the predetermined temperature but becomes at least partially opaque.

3. An indicator according to claim 2, wherein the indicator changes its transparency due to solidification on freezing, at and below the predetermined temperature.

4. An indicator according to any of claims 1 to 3, wherein the chemical is a liquid at least when transparent.

5. An indicator according to claim 4, wherein the chemical is selected to change U-ansparency at a predetermined temperature between -2 and -, 5 degrees C, more preferably 0 and 4 degrees C, and most preferably 1 and 3 degrees C.

6. An indicator according to claim 4 or claim 5, wherein the chemical is oil or water based.

7. An indicator according to any of claims 1 to 6, wherein the chemical is ethyl sebasate, which changes from a transparent liquid to a somewhat opaque solid at 2 degrees C.

8. An indicator according to any of claims 1 to 7, wherein the pocket or pockets in which the chemical is incorporated are suitably shaped so that the shape of the reflector is visually changed when the environmental temperature falls below the predetermined temperature.

9. An indicator according to claim 8, wherein the pocket or pockets may be so shaped that the letters ICE are revealed at and below the predetermined temperature.

10. An indicator according to claim 8, wherein a normalIv round reflector becomes partially obscured to show a triangular shape at and below the critical temperature.

11. An indicator according to any of claims 1 to 10, wherein, by the incorporation of differently coloured reflectors in the same indicator, and by use of different chemicals in association with the different reflectors, it is enabled to indicate two or more predetermined temperatures, such as 4 degrees C, 3 degrees C and 1 degree C.

12. An ice warnina indicator substantially as hereinbefore described.

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12. An indicator according to claim 11, comprising a graduated indicator.

13. An indicator according to any of claims 1 to 12, comprising a reflecting layer and a lens, and one or more chemical containing pockets between the reflector and the lens.

a i 1 14. An indicator according to claim 13, wherein the pocket or pockets are formed as one or more recesses in the reflector or the lens, preferably the former.

15. An ice warning indicator substantially as hereinbefore described.

1 Amendments to the claims have been filed as follows Claims An ice danger indicator comprising a reflector at least in part covered by one or more pockets containing a chemical exhibiting a change in transparency at a predetermined temperature at which ice may form in the vicinity, whereby to change the visual appearance of the reflector, wherein the chemical is such that it is fully transparent above the predetermined temperature but becomes at least partially opaque due to solidification on freezing, at and below the predetermined temperature.

2. An indicator according to claim 1, wherein the chemical is a liquid when transparent.

3. An indicator according to claim 2, wherein the chemical is selected to change transparency at a predetermined temperature between -2 and +5 degrees C, more preferably 0 and 4 degrees C, and most preferably 1 and 3 degrees C.

0 4. An indicator according to claim 2 or claim 3, wherein the chemical is oil or water based.

5. An indicator according to any of claims 1 to 4, wherein the pocket or pockets in which the chemical is incorporated are suitably shaped so that the shape of the reflector is visually changed when the environmental temperature falls below the predetermined temperature.

6. An indicator according to claim 5, wherein the pocket or pockets are so shaped that the letters ICE are revealed at and below the predetermined temperature.

7. An indicator according to claim 5, wherein a normally round reflector becomes partially obscured to show a triangular shape at and below the critical temperature.

8. An indicator according to any of claims 1 to 7, wherein, by the incorporation of differently coloured reflectors in the same indicator, and by use of different chemicals in association with the different reflectors, it is enabled to indicate two or more predetermined temperatures, such as 4 degrees C, 3 degrees C and 1 degree C.

9. An indicator according to claim 8, comprising a graduated indicator.

10. An indicator according to any of claims 1 to 9, comprising a reflecting layer and a lens, and one or more chemical containing pockets between the reflector and the lens.

11. An indicator according to claim 10, wherein the pocket or pockets are formed as one or more recesses in the reflector or the lens, preferably the former.