Field

[0001 ] The invention relates to airfield lighting, which may be either portable or fixed. For convenience, the present invention will be described with particular reference to portable lighting for temporary airfields.

Background

[0002] Airfield lighting systems are used to direct planes during landing, take-off and taxiing. Pilots rely on these lights for guidance, especially during times of low visibility, to identify airfield features such as runways and taxiways. Without functioning airfield lights, there can be disastrous consequences - for example, a plane may miss a runway or be unable to land or take off.

[0003] Conventional airfield lights use halogen lamps, which are very energy inefficient. In permanent airfields, this can result in increased energy costs, or in a worst case scenario, the failure of a power supply may make a runway unusable. For a temporary airfield, the problem is magnified, because temporary airfields often operate with limited power and/or do not have backup generators.

[0004] It would be desirable to provide an airfield light which is more energy efficient, or at least provides an alternative to existing airfield lights. It is known to practitioners skilled in the arts that Light Emitting Diodes can greatly reduce energy consumption in airfield lighting. To date the primary approach to using LED light sources is to simply replace the conventional light emitter with LED’s, while this improves the efficiency of the airfield light, the results are still not optimal. This invention provide an optimization of the electrical efficiency of LED airfield lights which is no achievable by the primary approach.

Summary

[0005] In a first aspect of the invention, there is provided an airfield light comprising:

a body; a first lighting arrangement, having a first intensity with an omni directional optical system;

a second lighting arrangement which is substantially unidirectional, having a second intensity that is higher than the first intensity.

[0006] The airfield light may include a third lighting arrangement which is similar to the second, but pointing in a substantially opposite direction.

[0007] As used herein, two quantities are“substantially” equal if they differ by less than 20%. And two entities are“substantially” aligned if they align within 20 degrees. In these and other respects,“substantial” generally means“nominal” as used herein.

[0008] The first lighting arrangement is preferably an intensity that would be known to practitioners of the art as a medium intensity airfield light. The first lighting arrangement is preferably an omnidirectional lighting arrangement, and may comprise one or more LEDs directed at a cone reflector.

[0009] The second lighting arrangement is preferably of an intensity known to practitioners of the art as a high intensity airfield light. The second lighting arrangement may be a unidirectional lighting arrangement or a bidirectional lighting arrangement, comprising one or more LEDs. The LEDs may be housed in a vertical light housing, with an open side or sides such that the LEDs can shine out the open side(s). The third lighting arrangement is similar to the second but illuminates in the opposite direction.

[0010] Preferred embodiments of the present invention therefore provide numerous advantages over conventional airfield lights. It enables a single light to provide both medium and high intensity lighting functions - which may be omnidirectional (medium intensity) or unidirectional (high intensity). The use of a unidirectional lighting in the second and third lighting arrangements provides high intensity light in either direction or which only one of the arrangement is required to be turned on. This means that the light of the present invention may be positioned on an airfield to shine in only the desired direction(s) - resulting in significant energy savings. These energy saving features are particularly important for lights used on temporary airfields. In addition, the use of a single light for both medium and high intensity lighting requirements means that the set up of a temporary airfield is simpler.

[001 1 ] The airfield light may further comprise a receiver to receive control signals to adjust a setting of the airfield light. The receiver may be wired or wireless. .

[0012] The control signals may selectively turn on or off the first and second lighting arrangements, or may specify patterns (e.g. flashing patterns), depending on the information to be transmitted by the light.

[0013] The body may comprise a substantially flat base, a light housing and/or a battery housing. The light housing may comprise a cone reflector, to reflect light from the first lighting arrangement omnidirectionally, and an open side or sides such that the second lighting arrangement may be directed out the open side. LEDs making up the second lighting arrangement may be aligned vertically within the light housing.

[0014] The light housing may be movable between an operative state and a transport state. Preferably, the light housing is foldable (or pivotable) between these states - wherein in the operative state, the light housing is substantially vertical, and in the transport state, the light housing is substantially horizontal.

[0015] The battery housing can house a battery to power the light - either as a primary power source, or preferably as a backup power source. The light preferably operates on an AC power source, with the battery as a backup in case the primary power source goes down. The use of a battery backup for an airfield light is considered to be a substantial improvement over conventional airfield lights.

[0016] In a second aspect of the invention, there is provided an airfield lighting system including multiple airfield lights according to any one of the preceding claims, wherein the lights are arranged on an airfield.

[0017] The lights may be individually controlled and/or powered, or may be controlled and/or powered collectively.

[0018] A detailed description of one or more embodiments of the invention is provided below, along with accompanying figures that illustrate by way of example the principles of the invention. While the invention is described in connection with such embodiments, it should be understood that the invention is not limited to any embodiment. On the contrary, the scope of the invention is limited only by the appended claims and the invention encompasses numerous alternatives,

modifications and equivalents.

[0019] For the purpose of example, numerous specific details are set forth in the following description in order to provide a thorough understanding of the present invention. The present invention may be practiced according to the claims without some or all of these specific details. For the purposes of clarity, technical material that is known in the technical fields related to the invention has not been described in detail so that the present invention is not unnecessarily obscured.

Brief Description of the Drawings

[0020] Embodiments of the invention will now be described with reference to the accompanying drawings wherein:

[0021 ] Figure 1 is a perspective view of an airfield light according to an embodiment of the present invention, in an operative state.

[0022] Figure 2 is a perspective view of the light of figure 1, in a transport (ie non operative) state.

[0023] Figure 3 is a side view of the light of Figure 1, in a transport (ie non operative) state.

[0024] Figure 4 is an end view of the light of Figure 1, in a transport (ie non operative) state.

[0025] Figure 5 is a perspective view of an airfield light according to an embodiment of the present invention, in a transport state.

Detailed Description

[0026] Referring to the figures, there is shown an airfield light 100 comprising a flat-based body 110, to sit firmly on the ground when the light 100 is installed. The body includes a light housing 120 and battery housing 130. [0027] The light housing 120 houses two lighting arrangements - a first, medium intensity lighting arrangement 150 and a second, high intensity lighting arrangement 160. The entire light housing 120 is installed on a bolt and wing nut arrangement 170, passing through a pivot mount 175, such that it can be moved between an operative state (as shown in Figure 1) and a non-operative or transport state (as shown in Figures 2 to 4). The wing nut can be tightened or loosened on the bolt to allow the light housing 120 to be respectively secured in a desired position, or moved between positions. In this embodiment, the light housing 120 folds or pivots about the bolt, to move the housing 120 between substantially vertical and substantially horizontal positions.

[0028] The medium intensity lighting arrangement 150 includes a medium intensity LED [typically 125 candela], which is located within the light housing 120 and directed upwardly onto a cone reflector 125. The light housing 120 includes a transparent section (e.g. formed of glass, Perspex or other transparent material) which allows light from the medium intensity lighting arrangement 150 to be directed in all directions, off of cone reflector 125.

[0029] The high intensity lighting arrangement 160 includes a bank of high intensity LEDs [typically up to 10,000 candela], and may include two banks of high intensity LEDs as in the embodiment of Figure 5. In these embodiment, each bank includes seven LEDs. In the embodiment of Figures 1 to 4, the housing 120 is open on one side, allowing the bank of high intensity LEDs to shine out that side. In the embodiment of Figure 5, the housing 120 is open on opposed sides, allowing the respective banks of high intensity LEDs 160 to shine out these open sides. The high intensity lighting arrangement(s) 160 are therefore a unidirectional or bidirectional arrangement, not an omnidirectional arrangement. In general, high intensity airfield lights are required to align with the direction of approach of a plane, particularly during take-off or landing. By recognizing that the high intensity light only needs to shine in the direction of a runway, the present invention uses a unidirectional or bidirectional high intensity light (rather than an omnidirectional light), resulting in significant power savings. In some embodiments, the opposed banks of high intensity LEDs shown in Figure 5 may be controlled individually, such that high intensity LEDs are only shined in a single direction. [0030] In the operative state, as shown in Figure 1, the light housing 120 is oriented substantially vertically, with the high intensity lighting arrangement directed horizontally in opposite directions from the body 110. These directions can be aligned with the direction of a runway.

[0031 ] In the transport state, as shown in Figures 2 to 4, the light housing is folded down substantially horizontally, so that it aligns with the profile of the battery housing 130. This means that the light 100 is more compact, and can be more easily transported.

[0032] The battery may be used as a primary power source in some embodiments of the present invention. However, in this preferred embodiment, the primary power source is an AC power source, and power cables can be run between aligned lights 100 to properly light a runway. The battery, therefore, acts as a backup power source. This is particularly important for temporary airfields, which frequently do not have a backup power generator.

[0033] The light 100 also includes an antenna 140, for receiving wireless control signals. The antenna 140 can also be folded down for transport or when not in use, as best shown in Figure 2, to reduce the likelihood of damage.

[0034] However, although the antenna 140 can be used to receive wireless control signals, control signals may be transmitted through communication cables. This avoids or reduces any interference with wireless communications between the plane and a control tower. Accordingly, cables between lights 100, arranged on an airfield, may also include communication wiring to enable wired communication between the lights 100 and a controller.

[0035] Control signals may be used to adjust settings of the light 100. Control settings may vary between different embodiments of the invention, but may include the following functionality:

• switching the medium intensity LED 150 on or off;

• switching either or both banks of high intensity LEDs 160 on or off;

• identifying a pattern or sequence of lighting configurations for the high intensity lights 160 or medium intensity light 150 - e.g. a flashing sequence. [0036] Although one embodiment of the present inventive has been described above, the invention is capable of many variations within the scope of the inventive concept. In particular, although the described embodiment makes use of LEDs, other lighting sources may also be used. For example, a halogen light source may be used and still obtain some of the benefits of the present invention.

[0037] In other embodiments, the light 100 may not need to be movable to a transport state, or may be moved in a different manner (for example, the light may be moved between operative and transport states by a sliding or telescoping

mechanism).

[0038] Throughout this specification and the claims which follow, unless the context requires otherwise, the word“comprise”, and variations such as“comprises” and“comprising”, will be understood to imply the inclusion of a stated integer or step or group of integers or steps, but not the exclusion of any other integer or step or group of integers or steps.

[0039] The reference in this specification to any prior publication (or information derived from it), or to any matter which is known is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.