Electronic signalling device

Abstract

An electronic signalling device comprising a light housing and an electrical power source. The light housing contains a lighting assembly having a longitudinal axis. The lighting assembly includes a plurality of lighting elements arranged in an angular array about the longitudinal axis. The lighting elements each comprise a light source and a focussing element. The focussing element is configured to create a focussed beam of light having a beam angle defining a central beam portion and a field angle defining an outer beam portion surrounding the central beam portion. Each lighting element is angularly offset from one or more angularly adjacent lighting elements in the array by an offset angle less than the field angle such that the beams of adjacent lighting elements overlap.

Description

ELECTRONIC SIGNALLING DEVICEFIELD OF INVENTION

[0001] The present disclosure relates to electronic signalling devices. In particular, the present disclosure relates to electronic visual distress devices.BACKGROUND

[0002] Both commercial and civilian vessels are required to carry visual emergency signalling devices. Pyrotechnic hand flares have historically been used, and an average light intensity of over 15,000 Candela is required by the International Maritime Organisation for distress flares. Other pyrotechnic distress signals include rocket parachute flares and buoyant smoke devices. There are numerous other use cases that require portable light signals of 15,000 Candela intensity including: aircrew life-rafts; fast location of mountain rescue teams thus saving helicopter fuel in casualty evacuation; Emergency Low Visibility Approaches (ELVA) for helicopter deck landings; marine location marking in a military setting; identification of drop zones for parachuting; identification of Helicopter Landings sites for troop extraction; and identification of Helicopter Landings sites for aerial work.

[0003] Although commonly used, pyrotechnic distress devices have numerous short comings. They burn for a short period of time; a rocket flare will only burn for around 40 seconds and a hand flare will only burn for about one minute. They have numerous safety risks that arise during manufacture, their transport between locations, and to the end user when activated. The reliability of pyrotechnic flares is susceptible to significant variations in ambient temperature. Pyrotechnic hand flares can cause severe burns on contact, serious eye damage, and have a risk of explosion if exposed to electric shock, friction, fire, or other sources of ignition. They can also risk vessel safety; for example pyrotechnic flares activated accidentally within sealed life rafts (e.g. when drop tested),can cause significant damage to the life raft and its contents. In addition, pyrotechnic flares are very toxic to aquatic organisms.

[0004] Electronic Visual Distress Devices (EVDS) including Light Emitting Diodes (LEDs) have been available since the early 2000s. They were developed as a safer, more durable, and more environmentally friendly alternative to traditional pyrotechnic flares. EVDS devices can generate long-lasting light for signalling purposes, including different colours and flashing patterns that enable Morse SOS. However, the effectiveness of LED flares in daylight is limited. Current EVDS devices have light intensities of around 75 Candela, which is not readily detectable in daylight at ranges of half a mile. As such, these devices do not meet current maritime regulations and the United States Coastguard for example approves EVDS devices for nighttime use only. Currently the Maritime and Coastguard Agency (MCA) does not recognise EVDS devices as a compliant signal method there are currently no EVDS products which meets the light intensity required by the International Maritime Organisation (IMO) for distress flares; i.e. average light intensity >15,000 Candela. This means that if a commercial vessel is required to carry flares, they cannot be an EVDS product.

[0005] It is therefore desirable to provide an improved electronic signalling device, which addresses the above-described problems and / or which offers improvements generally.SUMMARY

[0006] According to the present disclosure there is provided an electronic signalling device as described in the accompanying claims.

[0007] According to an aspect of the present disclosure there is provided an electronic signalling device comprising a light housing and an electrical power source. The light housing contains a lighting assembly having a longitudinal axis. The lighting assembly includes a plurality of lighting elements arranged in an angular array about thelongitudinal axis. The lighting elements each comprise a light source and a focussing element. The focussing element is configured to create a focussed beam of light having a beam angle defining a central beam portion and a field angle defining an outer beam portion surrounding the central beam portion. Each lighting element is angularly offset from one or more angularly adjacent lighting elements in the array by an offset angle less than the field angle such that the beams of adjacent lighting elements overlap.

[0008] The term "beam angle" is colloquially referred to as "Full Width Half Maximum" (FWHM). The term "field angle" is colloquially referred to as "Full Width Tenth Maximum" (FWTM). The angular array of lighting elements may be equidistantly spaced around the longitudinal axis, or may only partially encircle the longitudinal axis. The use of a focussing element, a battery and the overlapping of the beams around an axis have the combined effect of enabling a portable electronic signalling device that can provide rotational coverage at distances visible to search aircraft and nautical / surface vessels. The focussing element serves to focus the light produced by the light source. Whilst this focussing effects the entirety of the light produced by the light source, it importantly reduces the field angle to concentrate the light in the outer beam portion. As a result of this concentration, when the outer beam portion of one lighting element overlaps with an outer beam portion of another lighting element, their combined light output is similar to output of the central beam portion. By virtue of the beams of adjacent lighting elements overlapping, the outer beam portion and / or central beam portions may overlap. The lighting elements may be axially spaced from one another along the longitudinal axis. The term "one or more angularly adjacent lighting elements" should not be construed to require multiple angularly adjacent lighting elements. For example, two lighting elements angularly offset from one another by an offset angle fall within the scope of the present disclosure should they satisfy the requirements of the independent claims. It will be appreciated that by virtue of the offset angle being less than the field angle, the offset angle may be any angle that is greater than 0 degrees and less than the field angle. For example, the offset angle may be marginally less than the field angle, equal to the beam angle, or less than the beam angle (e.g. 1 degree).

[0009] The light housing has a radial axis perpendicular to the longitudinal axis, and the focussed beam of light has a beam axis. Each reflector may be angled upwardly such that the respective beam axis extends at an angle of elevation less than the beam angle relative to the respective radial axis. Thus, the beam axis of each reflector is angularly offset by the angle of elevation from the radial axis of their respective light housing. The use of a focussing element upwardly inclined at an angle of elevation of less than the beam angle, a battery, and the overlapping of the beams around an axis have the combined effect of enabling a portable electronic signalling device that can provide rotational coverage at distances visible to search aircraft, whilst also being optimally oriented to be visible nautical / surface vessels.

[0010] In an aspect of the disclosure there is provided an electronic signalling device, comprising a light housing and an electrical power source. The light housing contains a lighting assembly having a longitudinal axis and a radial axis perpendicular to the longitudinal axis. The lighting assembly includes a plurality of lighting elements arranged in an angular array about the longitudinal axis. The lighting elements each comprise a light source and a focussing element configured to create a focussed beam of light having a beam axis. Each reflector is angled upwardly such that the respective beam axis extends at an angle of elevation less than the beam angle relative to the respective radial axis.

[0011] Thus, the beam axis of each reflector is angularly offset by the angle of elevation from the radial axis of their respective light housing. The angular array of lighting elements may be equidistantly spaced around the longitudinal axis, or may only partially encircle the longitudinal axis. The provision of a reflector with a beam axis that is angularly offset at angle of elevation less than the beam angle from a radial axis of a light housing enables a portable device that directs light at the optimal upward angle such that the beams are visible to search aircraft, whilst also being visible to nautical vessels.

[0012] The focussed beam of light has a beam angle defining a central beam portion and a field angle defining an outer beam portion surrounding the central beam portion. Each lighting element may be angularly offset from one or more angularly adjacent lightingelements in the array by an offset angle less than the field angle such that the beams of adjacent lighting elements overlap. The term "beam angle" is colloquially referred to as "Full Width Half Maximum" (FWHM). The term "field angle" is colloquially referred to as "Full Width Tenth Maximum" (FWTM). The focussing element serves to focus the light produced by the light source. Whilst this focussing affects the entirety of the light produced by the light source, it importantly reduces the field angle to concentrate the light in the outer beam portion. As a result of this concentration, when the outer beam portion of one lighting element overlaps with an outer beam portion of another lighting element, their combined light output is similar to output of the central beam portion. By virtue of the beams of adjacent lighting elements overlapping, the outer beam portion and / or central beam portions may overlap. The lighting elements may be axially spaced from one another along the longitudinal axis. The term "one or more angularly adjacent lighting elements" should not be construed to require multiple angularly adjacent lighting elements. For example, two lighting elements angularly offset from one another by an offset angle fall within the scope of the present disclosure should they satisfy the requirements of the independent claims. It will be appreciated that by virtue of the offset angle being less than the field angle, the offset angle may be any angle that is greater than 0 degrees and less than the field angle. For example, the offset angle may be marginally less than the field angle, equal to the beam angle, or less than the beam angle (e.g. 1 degree). The use of a focussing element upwardly inclined at an angle of elevation of less than the beam angle, a battery, and the overlapping of the beams around an axis have the combined effect of enabling a portable electronic signalling device that can provide rotational coverage at distances visible to search aircraft, whilst also being visible to nautical vessels.

[0013] Further optional features of the disclosure will now be set out. These may be applied to any aspect of the disclosure singly or in any combination unless the context demands otherwise.

[0014] The lighting assembly may be provided in the form of a light cluster. Each light cluster may have first and second body sections, at least one body section having achannel for receiving the lighting elements. The first body section may be connected to the second body section such that each focussing element is retained between a respective channel in the first body section and a respective channel in the second body section.

[0015] The lighting housing may be a sealed housing in which the electrical power source and the light sources are disposed. The lighting housing may comprise a transparent element disposed over the focussing elements, such that the focussed beam of lights project through the transparent element. The lighting housing may comprise a handle. The lighting housing may comprise a seal disposed between the handle and the transparent element at an end of the transparent element. The lighting housing may comprise second seal and a cap, where the second seal is disposed between the cap and the transparent element at an opposing end of the transparent element.

[0016] Optionally, the offset angle is at least equal to the beam angle. By virtue of the offset angle being at least equal to the beam angle the central portions will not overlap. Thus, the lower intensity outer portions of the beam will primarily overlap with one another to provide a more consistent light intensity around the longitudinal axis. When the offset angle is equal to the beam angle the lower intensity outer portions of the beam will primarily overlap with the central portions, but the central portions will not overlap. Thus consistency of light intensity around the longitudinal axis is maximised.

[0017] Optionally, the focussing elements are reflectors, the reflectors each having a light projecting end from which the focussed beam of light is projected, and a light source receiving end for receipt of the light source. The use of reflectors may increase the light projection distance when compared to lens or similar focussing elements.

[0018] Optionally, the focussing elements focus the light along a beam axis.

[0019] Optionally, the angle of elevation is half the beam angle.

[0020] Optionally, the light assembly comprises a plurality of light clusters, each light cluster containing at least one lighting element, wherein the plurality of light clusters are arranged in an axially layered relationship. In such an axially layered relationship, each light cluster represents a layer of the light assembly. The angular offsetting between each of the layers may be narrowed to improve the overlapping of the beams. Additionally, this enables increased overlapping and thus improved light output around the longitudinal axis.

[0021] Each light cluster may have a plurality of lighting elements arranged in an angular array about the longitudinal axis. At least two of the plurality of light clusters may comprise the same number of plurality of lighting elements. Each light cluster may comprise the same number of plurality of lighting elements. Each of the statements relating to the light assembly and components thereof may apply to more than one of the light clusters.

[0022] Optionally, each light cluster is angularly offset from the one or more axially adjacent light clusters by an angle less than the field angle. This angular offset may define the offset angle.

[0023] Optionally, each light cluster contains a rotational alignment element configured to engage with an alignment element of another of the light clusters to rotationally position the light clusters relative to each other and define the angular offset between the light clusters. When the alignment elements are engaged the light clusters will be in an assembled configuration.

[0024] Optionally, the light sources are LEDs.

[0025] Optionally, the electronic signalling device further comprises a buoyancy element. The buoyancy element may comprise a plurality of buoyant chambers. The buoyancy element may be a separate float.

[0026] Optionally, the electronic signalling device further comprises a handle connected to the light housing, wherein the buoyancy element is formed integrally with the handle.BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present disclosure will now be described by way of example only with reference to the following illustrative figures in which:Figure 1 shows a schematic perspective representation of an electronic signalling device, according to an aspect of the present disclosure;Figure 2 shows a schematic perspective representation of an arrangement including a light source and a focussing element for use in an electronic signalling device, according to an aspect of the present disclosure;Figure 3 shows a schematic perspective representation of a light cluster for use in an electronic signalling device, according to an aspect of the present disclosure;Figure 4 shows a schematic perspective representation of an electronic signalling device, according to an aspect of the present disclosure;Figure 5 shows a schematic perspective representation of an arrangement including a light source and a focussing element for use in an electronic signalling device, according to an aspect of the present disclosure;Figure 6 shows a schematic perspective representation of a light cluster for use in an electronic signalling device, according to an aspect of the present disclosure;Figure 7 shows a schematic perspective representation of an electronic signalling device, according to an aspect of the present disclosure; andFigure 8 shows a schematic perspective representation of an electronic signalling device, according to an aspect of the present disclosure.DESCRIPTION OF EMBODIMENTS

[0028] The following description presents exemplary embodiments and, together with the drawings, serves to explain principles of the disclosure. The scope of the disclosure is not intended to be limited to the precise details of the embodiments or exact adherence with all method steps. Variations will be apparent to a skilled person and are deemed also to be covered by the description. Terms for features used herein should be given a broad interpretation that also encompasses equivalent functions and features. In some cases, several alternative terms (synonyms) for structural features have been provided but such terms are not intended to be exhaustive.

[0029] Descriptive terms should also be given the broadest possible interpretation; e.g. the term "comprising" as used in this specification means "consisting at least in part of" such that interpreting each statement in this specification that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner. Directional terms such as "vertical", "horizontal", "up", "down", "upper" and "lower" are relative terms that may be used for convenience of explanation usuallywith reference to the illustrations and are not intended to be ultimately limiting if an equivalent function can be achieved with an alternative dimension and / or direction.

[0030] The description herein refers to embodiments with particular combinations of configuration steps or features. However, it is envisaged that further combinations and cross-combinations of compatible steps or features between embodiments will be possible. The description of multiple features in relation to any specific embodiment is not an indication that such features are inextricably linked, and isolated features may function independently from other features and not necessarily require implementation as a complete combination.

[0031] Referring to Figure 1 an electronic signalling device 2 includes a housing 4, a control system (not shown), a battery (not shown), and a lighting arrangement 6. The lighting arrangement 6 comprises an upper light cluster 6a, an intermediate light cluster 6b and a lower light cluster 6c. The housing 4 comprises a plurality of seals 8a-d (provided in the form of O-rings), a cap 10, a cylindrical transparent shield 12 and a handle 14. The light clusters 6a-c are housed within the transparent shield 12, which is closed at one end by the cap 10 and at the other end by the handle 14.

[0032] The handle 14 is hollow and is substantially cylindrical. It has an open upper end 16 and a closed lower end 18. A power switch may be arranged towards the upper end 16 such that when the user grips the handle 14 they can actuate the power switch with their thumb. The handle 14 has a series of circumferential depressions 20 arranged along its length to improve grip. A circumferential recess 22a is located towards the upper end 16 of the handle 14 for receiving an O-ring 8a. An annular ridge or flange 24 protrudes radially away from the handle 14 and is located proximate and beneath the circumferential recess 22a of the handle 14 on the opposing side of the circumferential recess 22a to the upper end 16 of the handle 14. A second circumferential recess 22b receives a second O-ring 8b, and is located between the first circumferential recess 22a and the annular ridge 24.

[0033] The control system and battery are received within the handle 14, with the batteries being inserted through the open upper end 16. The control system is connected to the battery, the light clusters 6a-c and (where included) to the power switch. By way of example, when the user activates the power switch the control system activates / deactivates the light clusters 6a-c; depending on whether or not the light cluster is already in an activated state. More complex configurations may involve delays to activation / deactivation, and / or patterns of activation / deactivation, and / or activation / deactivation of select LEDs within the lighting arrangement 6.

[0034] The light clusters 6a-c are substantially the same, each having focussing elements in the form of five reflectors 26a-e disposed in a regularly spaced angular array about their circumference. The reflectors 26a-e direct light from five respective LEDs 28a-e radially outwardly from the electronic signalling device 2. The electronic signalling device 2 has a longitudinal axis defined along its length, and the light clusters 6a-c are axially stacked lengthwise. The lower light cluster 6c is lowermost in the stack and is positioned upon the upper end 16 of the handle 14. The intermediate light cluster 6b is positioned between the upper light cluster 6a and lower 6c light clusters. Light cluster 6a is upper most and is located immediately beneath the cap 10. The resultant arrangement of light clusters 6a-c can be considered a light cluster assembly.

[0035] The cap 10 comprises a circular top panel 11 and a substantially cylindrical body 15 section extending downwardly therefrom, the cap 10 having an upper end 30 and a lower end 32. A first circumferential recess 22c is located towards the lower end of the body 15 of the cap 10 that receives O-ring 8c. The top panel 11 of the cap 10 defines an annular ridge 34 that protrudes radially away from upper end of the body 15. A second circumferential recess 22d receives a fourth O-rings 8d, and is located between the first circumferential recess 22c and the top panel 11 of the cap 10.

[0036] The transparent protective shield 12 is formed as a hollow cylinder, with an open upper end 36 and an open lower end 38. The lower end 38 of the shield 12 receives the upper end 16 of the handle 14 and is seated upon the annular ridge 24 of the handle 14.The O-rings 8a, b of the first and second circumferential recesses 22a, b form an upper seal within the shield 12 between the inner surface of the shield 12 and the handle 14. This prevents any external fluids from passing into the electronic signalling device 2 at the junction of the handle 14 and the shield 12. The body 15 of the cap 10 is received in the upper end 36 of the shield 12 and the top panel 11 seats on top of and covers the upper end 36. The O-rings 8c, d received within the first and second circumferential recesses 22c, d of the cap 10 form a lower seal between the inner surface of the shield 12 and the body 15 of the cap 10. This prevents any external fluids from passing into the upper end of the electronic signalling device 2 at the junction of the cap 10 and the shield 12. Together the upper and lower seals prevent liquid ingress into the shield 12 and handle 14 of the electronic signalling device 2, protecting the light clusters 6a-c, battery and controller from water damage. The upper and lower seals are each formed using two O- rings to provide improved sealing. A single O-ring may form the upper and / or lower seal.

[0037] Referring to Figure 2, an LED column 40 of a light cluster 6a-c is shown. The LED column 40 includes a substantially cylindrical body defining a central support column 42. The LED column 40 has a circular flat base 44. LED modules 48a-e, each containing a single outwardly facing LED 28a-e and associated circuitry, are arranged in a rotationally symmetrical array around the circumference of the support column 42. In the case of five LED modules 48a-e (as shown), the LED modules 48a-e are angularly offset from one another by seventy-two degrees. Each LED 28a-e is oriented radially outwardly in a direction perpendicular to the longitudinal axis of the support column 42.

[0038] The reflector 26a (and each reflector 26b-e) is substantially hollow and rotationally symmetrical about a light projection axis 50, which extends outwardly away from the LED column 40. The reflector 26a extends between an inner LED receiving end 52 and an outer light projection end 54. Initially the reflector 26a has a cylindrical body portion at the LED receiving end 52, before flaring outwardly to form a conical portion 55 having a reflective inner surface. The LED receiving end 52 includes an aperture 56 in which an LED 28a of the LED column 40 is received.

[0039] The conical portion 55 of the reflector 26a has a reflective inner surface that reflects and focusses light from the LED 28a. The conical portion 55 forms an outwardly projecting light beam, having a beam angle 01 of approximately fifteen degrees, which contains light having intensity 50% or higher than the peak light intensity of the beam. The beam angle 01 defines a central beam portion. The beam also has a field angle 02 of approximately thirty degrees, which contains light having intensity 10% or higher than the peak light intensity of the beam. The field angle 02 defines an outer beam portion, being the beam portion within the field angle and outside the beam angle. A beam angle 01 of approximately fifteen degrees (e.g. twelve to eighteen degrees) is the most efficient light spread achievable with existing reflectors, but it will be appreciated that alternate beam angles 01 may be suitable for use in the device 2. Similarly, a field angle 02 of approximately thirty degrees (e.g. twenty to fifty-five degrees) is the most efficient light spread achievable with existing reflectors, but it will be appreciated that alternate field angles 02 may be suitable for use in the device 2.

[0040] The reflectors create a focussed cone of light projected along a beam axis. Each reflector 26a is angled upwardly away from the base of the LED column 40 at a projection angle 03 of approximately seven to eight degrees (corresponding to approximately half the beam angle) which orients the beam axis at angle 03 relative to the base of the light cluster, which in use angles the beam axis at angle 03 to the horizontal when the device is oriented vertically. This has been found to be the optimal beam axis angle for both signalling nautical vessels (at sea level) and search and rescue aircraft (at elevations of approximately 1500m).

[0041] Referring to Figure 3, a light cluster 6a includes an LED column 40 and five reflectors 26a-e retained within a light cluster housing 58. The light cluster housing 58 includes a lower portion 58a and an upper portion 58b, which are secured together by five screws 60a-e. To illustrate the arrangement of the reflectors 26a-e they are shown without the LED column 40.

[0042] The lower portion 58a has an upper surface 62 and a lower surface 64. A circular aperture 66 for receiving the LED column 40 is positioned centrally upon the upper surface 62 and passes through to the lower surface 64. An outer wall 68 protrudes upwardly away from the upper surface 62. Semi-circular cut-outs 70a-e are arranged around the outer wall 68, separated by an angular offset 04. In the case of five symmetrically arranged semi-circular cut-outs 70a-e (as shown), the semi-circular cutouts 70a-e are angularly offset by seventy-two degrees. Each of the semi-circular cut-outs 70a-e are configured to receive and support one of the reflectors 26a-e. The outer wall 68 is angled inwardly at seven to eight degrees from the vertical. As a result of this angling, the reflectors 26a-e are angled upwardly away from the upper surface 62 of the lower portion 58a at a projection angle 03 of seven to eight degrees (corresponding to approximately half the beam angle). Optionally, the reflectors 26a-e may be supported at a seven-to-eight degree angle by another support structure; which may or may not be formed integrally with the light cluster housing 58. Five apertures 72a-e for receiving the screws 60a-e are located around the outer wall 68 and are disposed angularly between the semi-circular cut-outs 70a-e. Reinforcing ribs may be positioned on the upper surface 62, each of rib extending to connect to the outer wall 68 at the location of one of the apertures. Such reinforcing ribs provide improved rigidity to the light cluster 6a-c. An alignment aperture 74 is angularly arranged between two of the apertures 72a-e and is radially offset from the circular aperture 66 by a predefined distance.

[0043] The upper portion 58b has an upper surface 76 and a lower surface. An angled outer wall 80 protrudes downwardly away from the lower surface. Five semi-circular cutouts 82a-e symmetrically arranged around the outer wall 80. Each of the semi-circular cuts-outs 82a-e is configured to receive one of the reflectors 26a-e. The outer wall 80 is angled outwardly at seven to eight degrees from the vertical. The upper surface 76 is substantially pentagonal in nature. Chamfered apertures 84a-e, each for receiving one of the screws 60a-e, are positioned at each corner of the upper surface 76; each chamfered aperture 84a-e passing from the upper surface 76 to the lower surface. An aperture 86 for receiving the LED column 40 is positioned centrally in the upper surface 76 and passes through to the lower surface. A keying projection 78 extends into the aperture, tocooperate with a corresponding notch in the LED column 40. An alignment protrusion 88 projects upwardly from the upper surface 76 and is radially offset outwardly from the notched aperture 86 by the same distance that the alignment aperture 74 is offset from the circular aperture 66 of the lower portion 58a. The alignment protrusion 88 is arranged at a first angular position on the upper surface 76.

[0044] To assemble a light cluster 6a the circular flat base 44 of the LED column 40 is positioned in the circular aperture 66 of the lower portion 58a of the light cluster housing 58, and the upper end 46 of the LED column 40 is positioned in the aperture 86 of the upper portion 58b of the light cluster housing 58. The positioning of the LED column 40 between these two apertures 66,86 axially restrains the LED column 40 between the upper 58b and lower 58a portions of the light cluster housing 58; whilst the interaction between the notch in the end 46 of the LED column 40 and the keying projection 78 in the aperture 86 rotationally locates and restrains the LED column 40. Each of the reflectors 26a-e are retained between one of the semi-circular cut-outs 82a-e of the upper portion 58b of the light cluster housing 58, and a corresponding one of the semi-circular cut-outs 70a-e of the lower portion 58a of the light cluster housing 58, which together form a circular cut-out 90a-e. The retainment of the reflectors 26a-e by these circular cut-outs 90a-e prevents relative movement between the light cluster housing 58 and the reflectors 26a-e. Each of the screws 60a-e are then passed through their respective chamfered apertures 84a-e in the upper portion 58b and screw into the corresponding apertures 72a-e in the lower portion 58a.

[0045] The alignment protrusion 88 and alignment aperture 74 are angularly position on the upper portion 58b and lower portion 58a respectively such that when the upper portion 58b is secured to the lower portion 58a there is an angular offset of twenty-four degrees between the alignment protrusion 88 and alignment aperture 74. The alignment protrusion 88 of one light cluster 6a-c is received by the alignment aperture 74 of another light cluster 6a-c when the light clusters 6 are stacked. The angular offset of the alignment protrusion 88 and alignment aperture 74 creates an angular offset between the stacked light clusters 6. Three stacked light clusters 6a-c, each having five reflectors per clusterwith an angular offset 04 of seventy-two degrees, and a twenty-four degree angular offset between each cluster 6a-c, results in fifteen reflectors positioned around the electronic signalling device 2 at twenty-four degree intervals (as best shown in Figure 1). As each reflector creates a light beam with a 30 degree field angle, the 24 degree angular interval between reflectors results in the light beams of angularly adjacent reflectors overlapping one another. This overlapping configuration amplifies the light in the overlapping regions, between the high intensity beam portion of each reflector, and results in a three-hundred-and-sixty degree high intensity light envelope around the electronic signalling device 2.

[0046] The electronic signalling device 92 shown in Figure 4 is configured in substantially the same way as the electronic signalling device 2 shown in Figure 1. Compared to the embodiment of Figure 1, the light arrangement 94 is configured differently, and a buoyancy device 95 connected to the handle 14 at its upper end 16. The buoyancy device 95 encircles the handle 14 and has a hollow, cylindrical form. The air sealed within the buoyancy device 95 provides the device with a positively buoyancy. Alternatively, the buoyancy device 95 could include a positively buoyancy material (such as a low-density polymer). The battery is located in the closed lower end 18 of the handle 14. As a result, the device 92 is self-righting when submersed in water, as the increased weight of the battery creates ballast and the upper end is buoyant, causing the device 92 to rotate to a vertical orientation such that the lighting arrangement 94 is supported and maintained above the waterline.

[0047] Referring to Figure 5, each light cluster 94a-c of the light arrangement 94 includes an LED column 96, an LED module 48 and a reflector 26 retained within a light cluster housing 98. The light cluster housing 98 includes a lower portion 98a and an upper portion 98b. The LED column 96 includes a substantially cuboid body defining a central support pillar. The LED module 48, contains a single outwardly facing LED 28 and associated circuitry, and is arranged upon a surface of the support pillar.

[0048] Referring to Figure 6, the lower portion 98a of the light cluster 94a has an upper surface 100 and a lower surface 102. A rectangular aperture 104 for receiving the LED column 96 is positioned towards the rear 106 of the upper surface 100 and passes through to the lower surface 102. An outer wall 108 protrudes upwardly away from the upper surface 100. A semi-circular cut-out 110 is arranged in the outer wall 108 and is configured to receive and support the reflector 26. The outer wall 108 is angled inwardly at seven to eight degrees from the vertical. As a result of this angling, the reflector 26 is angled upwardly away from the upper surface 100 of the lower portion 98a at a projection angle 03 of seven to eight degrees (corresponding to approximately half the beam angle). Optionally, the reflector 26 may be supported at a seven-to-eight degree angle by another support structure; which may or may not be formed integrally with the light cluster housing 98. An alignment aperture 112 is arranged substantially centrally in the lower portion 98a.

[0049] The upper portion 98b of the light cluster 94a has an upper surface 114 and a lower surface 116. An angled outer wall 118 protrudes downwardly away from the lower surface. A semi-circular cut-out 120 is arranged in the outer wall 118 and is configured to receive the reflector 26. The outer wall 118 is angled outwardly at seven to eight degrees from the vertical. A rectangular aperture 122 for receiving the LED column 96 is positioned towards the rear 124 of the upper surface 114 and passes through to the lower surface 116. An alignment protrusion 126 projects upwardly from the upper surface 114 and is arranged at a first angular position on the upper surface 114.

[0050] To assemble a light cluster 94a the LED column 96 is positioned in the rectangular apertures 104,122 of the upper and lower portions 98a, 98b of the light cluster housing 98. The positioning of the LED column 96 between these two apertures 104,122 axially and rotationally restrains the LED column 96 between the upper 98b and lower 98a portions of the light cluster housing 98. The reflector 26 is retained between the semi-circular cut-outs 110,120 of the upper and lower portions 98a, 98b of the light cluster housing 98, which together form a circular cut-out 128. The retainment of thereflector 26 by this circular cut-out 128 prevents relative movement between the light cluster housing 98 and the reflector 26.

[0051] The alignment protrusion 126 and alignment aperture 112 are angularly positioned on the upper portion 98a and lower portion 98b respectively such that when the upper portion 98b is secured to the lower portion 98a there is an angular offset of fifteen degrees between the alignment protrusion 126 and alignment aperture 112. The alignment protrusion 126 of one light cluster 94 is received by the alignment aperture 112 of another light cluster 94 when the light clusters 94 are stacked. The angular offset of the alignment protrusion 126 and alignment aperture 112 creates an angular offset between the stacked light clusters 94.

[0052] The angular offset between the three light clusters 94a-c is fifteen degrees, which defines the interval between the reflectors. Therefore, whilst the reflectors angularly overlap one another, the fact there are only three reflectors means a three- hundred-and-sixty degree light envelope is not created. Instead, the electronic signalling device 92 shown in Figure 4 has a forty-five degree light envelope of high intensity light. Whilst the light envelope is reduced, the power requirements are also significantly reduced. This provides a more directed light beam that takes advantage of overlapping clusters and upwardly angled LEDs while optimising power consumption.

[0053] The electronic signalling device 130 shown in Figure 7 in which the light arrangement 132 includes two light clusters 132a-b instead of three. Due to the decrease in the number of light clusters 132a-b, the height of the transparent shield 12 (between the open upper end 36 and open lower end 38) is proportionally decreased. Each of the light clusters 132a-b have three circular cut-outs 134a-c, instead of five. As a result, the cut-outs 134a-c are separated by one-hundred-and-twenty degrees. Additionally, the angular offset between each pair of adjacent light clusters 132a-b is sixty degrees. This lighting arrangement 132 results in six reflectors 26 positioned around the electronic signalling device 130 at an interval of sixty degrees. This described configuration of reflectors 26 results in six high intensity light envelopes around the circumference of thedevice 130, each having an arc of twenty-four degrees, separated by six medium intensity light envelopes with thirty-six degree arcs.

[0054] The electronic signalling device 136 shown in Figure 8 includes a single light cluster 138 instead of the three of Figure 1. Due to the decrease in number of light clusters 138, the height of the transparent light shield 12 is proportionally decreased, minimising the height of the device. The single light cluster 138 has five circular cut-outs 140a-e, separated by seventy-two degrees accommodating five reflectors 26. This seventy-two degree interval results in a three-hundred-and-sixty degree medium intensity light envelope around the electronic signalling device 136.

[0055] The electronic signalling device 136 shown in Figure 8 further includes a buoyancy device 142 connected to the handle 14 at its upper end 16. The buoyancy device 142 encircles the handle 14 and has a hollow, toroidal form. The air sealed within the buoyancy device 142 provides the device with a positively buoyancy. Alternatively, the buoyancy device 142 could include a positively buoyancy material (such as a low- density polymer). The battery is located in the closed lower end 18 of the handle 14. As a result, the device 136 is self-righting when submersed in water, as the increased weight of the battery creates ballast and the upper end is buoyant, causing the device 136 to rotate to a vertical orientation such that the lighting arrangement 138 is supported and maintained above the waterline.

[0056] In an alternate embodiment, an electronic signalling device is configured in substantially the same way as the electronic signalling device 2 shown in Figure 1 but with a different handle. The handle is substantially cylindrical comprising a buoyant tube. The provision of a handle formed as a buoyant tube reduces the overall footprint of the device by obviation the requirement for an additional external buoyancy element. Optionally the handle may also include an electronics section. In one arrangement the lower end of the buoyant tube is connected to the upper end of the electronics section. The upper end of the buoyant tube forms the upper end of the handle, and the lower end of the electronics section forms the lower end of the handle, although it will beappreciated that the reverse arrangement could also be applied. The control system and battery are received and housed within the electronics section and may be partially received within the lower end of the buoyant tube.

[0057] Further non-limiting example configuration of light housings include those configured such that the offset angle is 15 degrees (24 light clusters (LC) having 1 lighting element per cluster (LEpC); 12 LC having 2 LEpC; 8 LC having 3 LEpC; 6 LC having 4 LEpC; 8 LC having 3 LEpC; 12 LC having 2 LEpC), or 18 degrees (20 LC having 1 LEpC; 10 LC having 2 LEpC; 5 LC having 4 LEpC; 4 LC having 5 LEpC; 2 LC having 10 LEpC; 1 LC having 20 LEpC), or 20 degrees (18 LC having 1 LEpC; 9 LC having 2 LEpC; 6 LC having 3 LEpC; 3 LC having 6 LEpC; 2 LC having 9 LEpC; 1 LC having 18 LEpC), or 24 degrees (15 LC having 1 LEpC; 5 LC having 3 LEpC; 3 LC having 5 LEpC; 1 LC having 15 LEpC), or 30 degrees (12 LC having 1 LEpC; 6 LC having 2 LEpC; 4 LC having 3 LEpC; 3 LC having 4 LEpC; 2 LC having 6 LEpC; 1 LC having 12 LEpC), or 36 degrees (10 LC having 1 LEpC; 5 LC having 2 LEpC; 2 LC having 5 LEpC; 1 LC having 10 LEpC), or 40 degrees (9 LC having 1 LEpC; 3 LC having 3 LEpC; 1 LC having 9 LEpC), or 45 degrees (8 LC having 1 LEpC; 4 LC having 2 LEpC; 2 LC having 4 LEpC; 1 LC having 8 LEpC), or 60 degrees (6 LC having 1 LEpC; 3 LC having 2 LEpC; 2 LC having 3 LEpC; 1 LC having 6 LEpC), or 72 degrees (5 LC having 1 LEpC; 1 LC having 5 LEpC), or 90 degrees (4 LC having 1 LEpC; 2 LC having 2 LEpC; 1 LC having 4 LEpC), or 120 degrees (3 LC having 1 LEpC; 1 LC having 3 LEpC). Other non-limiting examples include 2 to 10 light clusters in an axial arrangement, where each light cluster contains a single lighting element. In one example 10 light clusters are arranged in an axial arrangement, where each light cluster is angularly offset from the previous light cluster by approximately 1 degree. The beam angles of the lighting elements of all 10 light clusters then overlap to maximise light output whilst still attaining angular coverage around the longitudinal axis.

[0058] A filter may be included in any of the electronic signalling devices to obstruct the focussed beam of light to produce light of a particular spectrum. For example, a red, green, blue, cyan or infrared (IR) filter may be used. The filter may be formed integrally with the shield, for example the shield may be formed of a tinted material. Alternatively, the filter may be provided in the form of a second tinted shield that encircles the shield.Alternatively, a filter element may be actuated relative to the shield, for example, the filter element may be slidably or hingedly mounted to the shield. The filter may be provided in the form of a film or wrap that connects to the shield. Any of the aforementioned filters may partially or fully cover the shield. For example, the film may be provided in the form of a patterned grid, where sections of the grid obstruct the beam of light to produce light of a particular spectrum, whilst other sections of the grid do not obstruct the beam of light.

Claims

Claims1. An electronic signalling device, comprising: a light housing containing a lighting assembly having a longitudinal axis, wherein the lighting assembly include a plurality of lighting elements arranged in an angular array about the longitudinal axis, the lighting elements each comprising a light source and a focussing element configured to create a focussed beam of light having a beam angle defining a central beam portion and a field angle defining an outer beam portion surrounding the central beam portion; and an electrical power source; wherein each lighting element is angularly offset from one or more angularly adjacent lighting elements in the array by an offset angle less than the field angle such that the beams of adjacent lighting elements overlap.

2. An electronic signalling device according to claim 1 wherein the offset angle is at least equal to the beam angle.

3. An electronic signalling device according to any preceding claim wherein the focussing elements are reflectors, the reflectors each having a light projecting end from which the focussed beam of light is projected, and a light source receiving end for receipt of the light source.

4. An electronic signalling device according to any preceding claim wherein the focussing elements focus the light along a beam axis.

5. An electronic signalling device according to claim 4 wherein the lighting assembly has a radial axis perpendicular to the longitudinal axis and the focusing elements are angled upwardly such that the beam axis extends at an angle of elevation less than the beam angle relative to the radial axis.

6. An electronic signalling device according to claim 5 wherein the angle of elevation is half the beam angle.

7. An electronic signalling device according to any preceding claim wherein the light assembly comprises a plurality of light clusters, each light cluster containing at least one lighting element, wherein the plurality of light clusters are arranged in an axially layered relationship.

8. An electronic signalling device according to claim 7 wherein each light cluster is angular offset from the one or more axially adjacent light clusters by an angle less than the field angle and greater than the beam angle.

9. An electronic signalling device according to claim 8 wherein each light cluster contains a rotational alignment element configured to engage with an alignment element of another of the light clusters to rotationally position the light clusters relative to each other and define the angular offset between the light clusters.

10. An electronic signalling device according to any preceding claim wherein the light sources are LEDs.

11. An electronic signalling device according to any preceding claim further comprising a buoyancy element.

12. An electronic signalling device according to any preceding claim comprising a handle connected to the light housing.

13. An electronic signalling device according to claims 10 and 11 wherein the buoyancy element is formed integrally with the handle.

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