GB2524107A

GB2524107A - Lighting systems

Info

Publication number: GB2524107A
Application number: GB1404661.9A
Authority: GB
Inventors: Sean O'kell
Original assignee: Saf T Glo Ltd
Current assignee: Saf T Glo Ltd
Priority date: 2014-03-14
Filing date: 2014-03-14
Publication date: 2015-09-16
Also published as: GB201404661D0

Abstract

A light 11 for an aircraft passenger cabin comprises an elongate casing 15 housing a light source 17. The casing has an elongate base 33and an elongate cover 35 secured together along both sides of the casing by co-operating formations 37,39 on the base and cover. The light source 17 may comprise a plurality of LEDs. The cover may be transparent or translucent. The base is preferably opaque and may be made from metal, plastic or composite.

Description

LIGHTING SYSTEMS

This invention concerns improvements in or relating to lighting systems. This invention has particular, but not exclusive, application to passenger transport vehicles (PTVs) such as aircraft, trains, buses and coaches. More especially, the invention is concerned with aircraft cabin lighting systems and parts and fittings for such lighting systems.

An embodiment of the invention provides a light comprising an elongate casing housing a light source, wherein the casing has an elongate base and an elongate cover secured together along both sides of the casing by co-operating formations on the base and cover.

An embodiment of the invention provides a bracket for mounting a light, wherein the bracket has a connector portion for attaching to the light, and the connector portion is adjustable to change the orientation of the light.

An embodiment of the invention provides a light having a light source and an interface, wherein the light source is programmable via the interface for calibrating light intensity and/or colour of a light output of the light source.

An embodiment of the invention provides a lighting system for an aircraft cabin, the lighting system including an electrical light source and a photoluminescent light source, wherein the electrical light source is configured to charge the photoluminescent light source.

The foregoing is a summary and thus by necessity contains simplifications, generalizations, and omissions of detail. Consequently, those skilled in the art will appreciate that the summary is illustrative only and is not intended to be in any way limiting. Other aspects, inventive features, and advantages of the devices and/or processes described herein will become apparent in the detailed description set forth herein and taken in conjunction with the accompanying drawings wherein: Figure t is a sectional view of an aircraft cabin; Figure 2 is an exploded perspective view ofa ceiling light unit; Figure 3 is a sectional view of the light unit shown in Figure 2; Figure 4 shows a bracket for mounting the ceiling light; Figure 5 is a perspective view showing the bracket attached to the ceiling light Figure 6 is a perspective view showing the ceiling light with four brackets attached; Figures 7 to 9 are sectional views similar to Figure 1 showing the light output for different orientations of the ceiling lights; and Figure 10 is an exploded perspective view of a wall light unit.

Referring first to Figure 1, there is shown a schematic lay-out of the interior of an aircraft cabin I within the aircraft fuselage 3, The cabin 1 is provided with passenger seats 5 on both sides of a central aisle 7 for movement of passengers to their allocated seats on boarding the aircraft and to the aircraft exit(s) on leaving the aircraft. The seats 5 are arranged in rows (one only shown) spaced apart along the length of the cabin. Located above the seats 5 on both sides of the aisle 7 are overhead storage units 9 that extend along the length of the cabin.

In this embodiment, there are six seats 5 in each row, three either side of the aisle 7, It will be understood however that the number and layout of the seats S and/or aisles 7 and/or storage units 9 may vary according to the type of aircraft and the layout shown is not limiting on the scope of the invention.

The cabin I is provided with a lighting system including ceiling lights ii located on top of the storage units 9 on both sides of the aisle 7 and wall lights 13 located on the underside of the storage units 9 on both sides of the aisle 7. Other locations of the ceiling lights Ii and wall lights H may be employed. In some arrangements, it may be that the wall lights 13 are omitted. In other arrangements it may be that the ceiling lights 11 are omitted.

The ceiling lights II and wall lights 13 are preferably arranged along the length of the cabin. The ceiling lights 11 may be orientated to illuminate the cabin ceiling and the wall lights 13 may be orientated to illuminate the cabin walls. The ceiling lights II and wall lights 13 may comprise any suitable light source such as a fluorescent light source or a light emitting diode (LED) light source.

Where an LED light source is employed, the light source may be controlled to vary the brightness and/or colour of the emitted light. A power source for the ceiling lights 11 and wall lights 13 may be provided by the aircraft power supply (not shown). Controls for the ceiling lights Ii and wall lights 13 may be arranged for operation by the flight crew and/or cabin crew.

A ceiling light 11 is shown in more detail in Figure 2. The ceiling light 11 has an elongate casing 15 housing a plurality of LEDs 17. The LEDs 17 are preferably spaced apart along the length of the casing 15.

The LEDs may be mounted on a support member 19. The support member 19 preferably extends the length of the casing 15. The support member 19 may comprise at least one printed circuit board. The casing 15 may further include end caps 21, 23. The LEDs may be arranged in one or more strings. The LEDs provide visible light for illumination, The LEDs may provide white light and/or coloured light.

The ceiling light I is connectable to the power source to power the LEDs. For example, the support member 19 may have a connector 25 at one end that is received in an opening 27 in the end cap 21 for releasably attaching a mating connector 29 of a power supply cable 3 1 (Figure 5) to connect the support member 19 to the power source to power the LEDs, Each ceiling light t t is preferably connected to the power source by a separate power supply cable 31, Each ceiling light 11 may be operated independently of the other ceiling lights.

A sectional view of the assembled casing 15, LEDs V/ and support member 19 is shown in Figure 3. The casing 15 comprises a base 33 and a cover 35. The base 33 is preferably opaque. The cover 35 is preferably transparent or translucent, The base 33 may be made of metal or alloy, for example aluminium, although other materials may be used including plastics and composites of plastics with metal or alloy.

The cover 35 may be made of plastics, for example polycarbonate, although other materials may be employed. The base 33 may be an extrusion and may be cut to length from an extruded profile. The cover 35 may be an extrusion and may be cut to length from an extruded profile.

The base 33 and cover 35 may be releasably secured together. For example the base 33 and cover 35 may have longitudinal formations configured to engage along both sides of the casing 15 to secure the cover 35 to the base 33. The formations may engage with a snap action that allows the cover 35 to be clipped onto the base 33. The base 33 may be of channel-section. The cover 35 may be of semi-circular section. Sidewalls of the base 33 may be configured to provide internal longitudinal channel formations 37 that receive and retain external longitudinal rib formations 39 on side edges of the cover 33 to secure the cover 35 to the base 33.

The support member 19 is preferably mounted in the cover 35. For example, the cover 35 may have longitudinal formations configured to locate longitudinal side edges of the support member 19 along both sides of the casing 15 to mount the support member 19 in the cover 35.

The cover 35 may be configured to provide internal longitudinal grooves 41 to receive and retain the side edges of the support member 19. The LEDs 17 are located wholly within the cover 35. This may assist to optimise the illumination provided by the LEDs 17.

Once the base 33 and cover 35 are assembled with the support member 19 located in the cover 35, the end caps 21, 23 can be attached to the ends of the casing 15. It may be that the end caps 21, 23 are releasably attached at the ends of the casing 15. For example, sidewalls of the base 33 may be provided with one or more formations to receive a fastener to secure the end caps 21, 23. The sidewalls of the base 33 may be provided with longitudinal openings 43 to receive screws 45 to attach the end caps 2], 23. The screws 45 may be self-tapping.

A bracket 47 for mounting the ceiling light ii is shown in Figure 4 and attached to the ceiling light I I in Figure 5, The bracket 47 has a base 49 for securing to a mounting surface, for example the top of the storage units 9 and a connector 51 for attaching the ceiling light 11 The base 49 may be rectangular in plan view although other shapes may be employed. The bracket 47 may be secured to the mounting surface by one or more fasteners, preferably in a releasable manner. For example the bracket 47 may be secured by one or more screws.

The connector 51 is preferably configured to receive and retain the base 33 of the casing 15 of the ceiling light t t to secure the casing 15 to the bracket 47. The base 33 and connector 51 may be releasably secured together. For example the base 33 and connector 51 may have longitudinal formations configured to engage along both sides of the casing 15 to secure the casing t5 to the bracket 47. The formations may engage with a snap action that allows the casing 15 to be clipped onto the bracket 47. The connector 51 may be of channel-section.

Sidewalls of the connector 51 may be configured to provide internal longitudinal rib formations 53 and sidewalls of the base 33 may be configured to provide external longitudinal channel formations 55 that receive and retain the longitudinal rib formations 53 to secure the casing 15 to the bracket 47.

As will be understood, the ceiling light 11 can be provided in a range of lengths to adapt the lighting system for different aircraft and, depending on the length of the ceiling light 1], one or more brackets 47 may be attached spaced apart along the length of the casing 15 to provide adequate support for installation of the ceiling light I I For example, Figure 6 shows four brackets 47 spaced apart along the length of the ceiling light 11 The connector 51 preferably extends at an angle "a" to the base 49. The angle may be chosen to orientate the ceiling light Ii to control the direction of the light output from the LEDs, The angle may be fixed and brackets 47 provided having a range of angles for the installer to select and fit the appropriate bracket 47. Alternatively, the bracket may be adjustable to vary the angle. For example, the connector 51 may be configured for pivotal movement relative to the base 49 to adjust the angle at which the connector 51 extends to the base, It may be that the connector 51 is attached to the bracket 47 by a hinge portion 55 and a device 57 is provided to pivot the connector 51 about the hinge portion 55 to adjust the angle between the connector 51 and the base 49.

The device 57 may provide continuous adjustment of the angle over the range. For example pivotal movement may be controlled by a screw type adjuster or similar, Alternatively, the device 57 may provide stepwise adjustment of the angle over the range. For example pivotal movement may be controlled by a ratchet type adjuster or similar, The range of adjustment may be from 0 to 180 degrees, preferably from 0 to 90 degrees, more preferably from 15 to 75 degrees and most preferably from 30 to 60 degrees.

Adjusting the orientation of the ceiling lights I I changes the direction of the light output. Figure 7 shows the light output for a bracket angle of 30 degrees, Figure 8 shows the light output for a bracket angle of 45

S

degrees, and Figure 9 shows the light output for a bracket angle of 60 degrees. These angles are provided for illustration only and are not intended to be limiting on the range of angles that may be employed.

As shown, changing the direction of the light output by altering the orientation of the ceiling lights II changes the area covered by reflection of light from the ceiling of the cabin. In particular, the reflected light with the bracket angles of 30 degrees and 60 degrees is more concentrated in the area of the aisle 7 than with the bracket angle of45 degrees.

Controlling the direction of the light output by adjusting the orientation of the ceiling lights II may be used in combination with emergency lighting systems that employ photoluminescent material, Photoluminescent material absorbs and emits light when exposed to a light source and continues to emit light for a period of time after the light source is no longer available.

The photoluminescent material may be incorporated in tracks 59, 61 arranged to extend along one or both sides of the aisle 7. The illumination provided by the photoluminescent material may not be visible under normal lighting conditions in the cabin. However, in an emergency, it may be that the ceiling lights 11 and wall lights 13 are not working due to loss of the power supply to the lighting system, for example the wiring may be damaged, or the light is blocked due to the presence of smoke in the cabin, for example as the result of a fire.

In these conditions, the light emitted by the photoluminescent material is visible and the tracks 59, 61 define a path along which passengers can move to an exit when the aircraft is evacuated in an emergency.

The path may be continuous. The path may be configured according to the layout of the aircraft to include sections that are straight or curved.

However, it may be that locating the photoluminescent material on or near floor level at the sides of the aisle reduces the exposure of the photoluminescent material to sources of light necessary to charge the photoluminescent material and to maintain the photoluminescent material in a charged condition.

It is desirable that the photoluminescent material is in a fully charged condition at the time of an emergency to maximise both the brightness and the duration of the emitted light when the aircraft electrical lighting system may not be working or may be rendered ineffective by the presence of smoke in the cabin. By adjusting the orientation of the ceiling lights ii so that the light output is more concentrated in the region of the aisle 7, it may be that the time to charge the photoluminescent material may be reduced and/or it may be that the photoluminescent can be maintained in a fully charged condition prior to being required in an emergency.

A wall light t3 is shown in more detail in Figure 10. Like reference numerals are used to indicate the same or similar parts to the ceiling light 11 shown and described with reference to Figure 2. The same or similar parts will be understood from the description of the ceiling light 11 and are therefore not described in detail again.

The casing 15 of the wall light t3 is provided with end caps 63, 65 with integral brackets 67, 69 for mounting the wall light 13 on a mounting surface, It will be understood that the wall light 13 could be mounted using one or more of the brackets 47 as described above for the ceiling lights II if desired, In this case, the end caps 63, 65 could be replaced by end caps without the integral brackets 67, 69.

The support member 19 for the LEDs 17 is provided with connectors 71, 73 at both ends that are received in openings 75, 77 in the end caps 63, 65. The connectors 71, 73 may be the same or different. The connectors 71, 73 allow two more wall lights 13 to be connected together in series and powered by the same power source so as to be operated together. It will be understood that the wall lights 13 could be connected to the power source by separate power supply cables as described above for the ceiling lights 11 if desired.

It may be that the above-described ceiling lights II and/or wall lights 13 are provided with an interface which enables the light intensity and/or colour blend levels of the light output from each light ii, 13 to be adjusted independently of the other ceiling lights ii and/or wall lights H. In this way, the light output of the lights II, H can be calibrated to suite requirements of a given installation, A control device, for example a handheld remote (not shown), may be used for calibrating the lights ii, 13.

The remote may communicate with the interface via a wireless link, for example an infra-red link, In other arrangements a wired link may be employed. The remote may be provided with an infra-red transmitter and each light 11, 13 may be provided with an infra-red receiver 79.

The receiver 79 may be located on the support member t9. Each light ii, 13 may have a calibration memory. Access to the calibration memory may be protected to prevent inadvertent or unauthorised access to the calibration memory. For example, access may require a sequence of commands in the correct order and within a permitted window (time) before calibration adjustments can be made and then stored in the calibration memory.

Adjusting the light intensity and/or colour blend levels of each light 11, 13 independently may be useful when replacing a damaged or broken light, the light intensity and/or colour blend levels of the new light can be adjusted to match those of the other lights. It may be that the lights ti, t3 have a plurality of light intensity settings, for example low (dim), medium (normal) and high (bright). Each setting may be calibrated. The lights may be controlled to select the same or different settings according to the location of the lights and requirements.

Claims

CLAIMSA light for an aircraft comprises an elongate casing housing a light source, wherein the casing has an elongate base and an elongate cover secured together along both sides of the casing by co-operating formations on the base and cover.
2. A light according to claim I wherein the co-operating formations comprise longitudinal formations along the sides of the base and cover that are engageable to secure the cover to the base.
3. A light according to claim 2 wherein the co-operating formations are releasable such that the cover is detachable from the base.
4. A light according to any preceding claim wherein the co-operating formations engage with a snap action.
5, A light according to any of preceding claim wherein the base is channel-section and the cover is of semi-circular section.
6. A light according to any preceding claim wherein the co-operating formations comprise internal longitudinal channel formations on sidewalls of the base and external longitudinal rib formations on side edges of the cover that are engageable to secure the cover to the base.

7, A light according to any preceding claim further comprising an elongate support member for mounting the light source in the cover, 8, A light according to claim 7 wherein the cover has longitudinal formations configured to locate longitudinal side edges of the support member along both sides of the casing to mount the support member in the cover.9. A light according to claim 8 wherein the cover is configured to provide internal longitudinal grooves to receive and retain the side edges of the support member.0. Alightaccordingtoanyofclaims7to9whereinthelightsource comprises a plurality of light emitting diodes mounted on the support member and located wholly within the cover.11. A light according to any preceding claim further comprising end caps at both ends of the casing.U, A light according to any preceding claim wherein the base is configured for attaching a bracket to mount the light on a support surface.H. An aircraft having a passenger cabin having an electrical lighting system comprising a plurality of lights arranged along the length of the cabin, each light being in accordance with any of claims Ito 12, 14. An aircraft according to claim 13 wherein a first plurality of lights are ceiling lights and a second plurality of lights are wall lights.