This invention relates to portable lighting, and particularly to lighting units suitable for lighting events.

Increasingly, events are held in a variety of venues, many of which are not designed with the hosting of events as a primary purpose. For example, an event may be held in a museum, a gallery or a stately home, or in an individual's house or garden or other out of doors location. In such cases, there may be little or no provision of permanent, specialist infrastructure for event production, and in particular for the installation of lighting for the event. At the same time, the scale on which some events are held is increasing. There is often a need to light a room from multiple points in all three dimensions; consequently, it is common for lighting units for an event to be suspended or otherwise positioned at various heights.

Thus, events designers are required to conceive of ever-more innovative and practical lighting solutions in view of the conflicting needs to ensure a suitable power supply and the ability to control the lighting, whilst respecting both health and safety requirements and the need to achieve satisfactory presentation.

In the past, lighting units have been powered and controlled during an event by means of appropriate cables. However, this makes the installation of the lighting time-consuming and involved, increasing costs and generally being inconvenient for the host of the event. Furthermore, the use of wired lighting, in particular in a hanging or suspended

configuration, often presents a hazard and is unaesthetic, requiring the designer to go to great lengths to hide the cables from view. This is especially so in the case of larger-scale events in which many individual units may be positioned throughout a room, some of which may require long lengths of cable from limited power connection or control points.

Recently, rechargeable, battery-powered wireless lighting units have been provided to overcome some of these problems. GB 2484758 discloses one such unit. As shown in Figure 1 , the battery-operated remote controllable uplighter 910 of GB 758 comprises a housing 920 including an upper surface 950, in the centre of which is arranged an LED light 960. An antenna 980 for receiving control signals is located in a corner of the upper surface. However, this and the other wireless units currently available are unsuitable for use in a suspended configuration. These units are typically large in size, heavy and generally cumbersome, so as to be limited to use as floor-standing uplighters. The applicability of the lighting unit of GB 758 in particular is further restricted due to the limited range of directionality of the light source 960. In addition, the battery lifetime and other technical specifications of the wireless lights currently on the market can be inadequate for many events, these units often being economically inefficient to run and requiring frequent replacement.

Thus, it would be desirable to provide an improved lighting unit for use, for example, in event production.

The invention is defined in the independent claim, to which reference is now directed. Preferred features are set forth in dependent claims.

According to the invention there is provided a wirelessly operable lighting unit comprising a housing, a battery arranged within the housing, an antenna for receiving control signals for the lighting unit, and a lamphouse coupled to a first surface of the housing, the lamphouse housing a light source. A second surface of the housing is configured for coupling to suspension means for suspending the lighting unit in a hanging configuration.

The lighting unit may be, for example, a wash light.

Embodiments of the invention may advantageously provide a lighting unit that can be used in a suspended configuration without any need for a connection to a mains power supply or to control wiring. The installation of hanging lighting at an event venue may therefore become more straightforward and less time-consuming. Since fewer skilled technicians may be required, events that make use of hanging lighting units may also be arranged and hosted in a more cost-effective manner. In addition, the need for visually unpleasing and potentially hazardous wiring when using suspended lighting may be removed.

Furthermore, the lighting may be controlled remotely during the event. In this case, the entirety of the lighting effects employed in the event may be adjusted without the need to interrupt the event itself notwithstanding the absence of any cables or wiring to one or more external control points. Thus, it may become possible to increase the range of lighting effects that can be employed when designing an event to be staged in a totally wireless fashion. In preferred embodiments of the invention, the lighting unit may further be used in a standing position as an uplighter. Thus, a multi-purpose lighting unit of improved flexibility may be provided. This may mean that fewer specialist designs of lighting unit are required to achieve the range of functionality and effect that can be required in designing and hosting an event, such that the installation of an event may be simplified still further.

According to some embodiments of the invention, a bracket is removably attachable to a second surface of the housing for receiving the suspension means for suspending the lighting unit. With this arrangement, the lighting unit may be configured for hanging or for use in a standing position, as appropriate, in a quick and straightforward manner. Preferably, the lamphouse is tiltable with respect to the first surface of the housing. This may be especially advantageous in the context of ceiling lighting, where the possible positions of a bar or rail from which the lamp is to be hung may be limited. In addition, it may not be easy or even possible to adjust the angle at which the housing itself is mounted to the rail. By arranging the lamphouse to tilt relative to the housing, it may nonetheless become possible to direct the light as desired.

In preferred embodiments of the invention, the lamphouse is mounted on a yoke, the yoke being coupled to the first surface of the housing. In this case, the lamphouse may be made to tilt through a wide range of angles, such that the flexibility of the lighting unit may be improved. In some embodiments, the lamphouse is rotatable with respect to the first surface of the housing, so as to effect a panning motion. In this way, the span of points that may be lit by the unit may be increased still further. It may also become easier in this instance to direct the light emitted by the unit as desired. In particular, the light emitted by the light source may be directed to any point within a solid cone without the need to angle the housing of the lighting unit relative to the bar or stand from which it is hung which, as mentioned, can be comparatively difficult. In addition, to direct the light output by the lighting unit by rotating the housing itself about the clamp by which it is suspended can mean that the front face and its display panel become visible to guests of an event, which can be undesirable. According to embodiments of the invention, the lighting unit may be suspended in a most aesthetically preferred position at the outset, there being no need to move it from that position to achieve desired lighting effects during an event. Where the lamphouse is mounted on a yoke, the rotational degree of freedom may be realised by configuring the yoke itself to rotate relative to the housing. Preferably, the lighting unit further includes a detachable barndoor shutter accessory, which may provide increased control of the light beam emitted by the unit. The barndoor may comprise a bezel attachable to the front of the lighting unit, and a plurality of articulated doors or wings coupled to the bezel for shaping and directing the light beam in use.

In some embodiments, the light source is an LED light source. In these examples, the lighting unit further comprises an LED driver for the light source, the driver being arranged within the lamphouse. An LED light source may be preferred over conventional light sources such as fluorescent or incandescent lamps as LED technology may provide a light source of improved lifespan, which also benefits from reduced power requirements and lower operating costs. As is known to those in the art, LED lighting is additionally increasingly preferred on account of its reduced environmental impact with respect to conventional lighting technologies.

Preferably, the light source includes a plurality of LEDs, at least one of which is configured to emit light having a range of wavelengths different to that of the light emitted by at least one other of the LEDs. In this case, the lighting unit further comprises a colour mixing regulator circuit arranged within the lamphouse for controlling the output of the light source. Thus, a colour mixing unit may be provided, which may have a wider range of application than a lighting fixture capable of outputting white light or light of a single other colour only. In some embodiments, the LED light source is a multi-chip LED light source. In this case, since a plurality of LEDs is integrated into a single package, light having a high intensity and/or varying wavelengths may be produced without unduly increasing the weight of the light source or the degree of packaging material required. In addition, the removal of heat radiated by the light source may be made more efficient, and the LEDs may further be powered by a single driver. Multi-chip LED technology is known to provide light sources having a long lifetime and a comparatively low cost. Additionally, use of a single light source and lens can mean that problems associated with the generation of multiple shadows from a plurality of light sources included in a single unit are avoided.

According to preferred embodiments of the invention, the battery is rechargeable and the lighting unit further comprises means for connecting the battery to an external power supply, whereby the battery may be charged without being removed from the housing. By removing the need to replace the batteries or to remove them for recharging, repeated use of the lighting unit of these embodiments may be more efficient and less time-consuming than has previously been the case. In addition, the housing may be substantially sealed, such that penetration by water, dust or other contamination that may adversely affect the operation of the unit may be reduced or avoided.

Preferably, the battery is a lithium iron phosphate (or lithium ferrophosphate, LFP) battery. This chemistry can provide an advantageously long battery life, such that the lighting unit may be powered for multiple hours before it becomes necessary to recharge the battery. In addition, the battery may be subjected to an increased number of charging and discharging cycles before its operation becomes inefficient or unreliable. Furthermore, LFP battery technology is currently the most environmentally friendly available. The battery in these examples may also be light in weight, which is particularly advantageous where the lighting unit is to be used in a hanging configuration.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a perspective view of a battery-operated remote controllable uplighter of the prior art;

Figure 2 is a schematic illustration of a lighting unit according to one embodiment of the present invention;

Figure 3A is an alternative view of the lighting unit of the embodiment shown in Figure 2;

Figure 3B illustrates the lighting unit of Figures 2 and 3A in use with a suitable (third party) clamp for suspending the lighting unit;

Figure 4 is an exploded view of a lamphouse of the lighting unit of Figures 2, 3A and 3B;

Figure 5A is a perspective view of a barndoor accessory suitable for use with a lighting unit according to the invention, in an open configuration; and

Figure 5B is a perspective view of the barndoor accessory of Figure 5A in a closed configuration.

Figure 2 is a schematic illustration of a wireless lighting unit 1 according to one

embodiment of the present invention. In this embodiment, the lighting unit is used as a wash light, either in a standing position on a floor or other surface, or in a hanging configuration, as will be described. As shown, the unit 1 includes a housing 10 at its base. The housing is of substantially square cross-section, having rounded corners for reasons of safety and aesthetics, and encloses a rechargeable battery (not shown) that provides electrical power for the lighting unit, as will be described below. In this example, the housing is made of a substantially rigid, lightweight metai such as aluminium, and is sealed along its edges to prevent the ingress of water, dust or other external substances that could potentially damage the battery. In other embodiments, the shape, size and material of the housing could be varied as appropriate. For example, the housing could be made from polycarbonate, acrylic or any other suitable material. Though not essential, it is preferable for the housing to be made from a metal or other material having a relatively high thermal conductivity. In this case, the heat generated by the battery and circuitry contained within the housing may be dissipated efficiently through the walls of the housing itself. Consequently, it can become possible to reduce the size of the housing and thus the weight of the unit as a whole, since the need to include substantial volumes of air in the regions surrounding these components can be reduced. As a result, suspension of the unit may be made more safe, and it may be easier to suspend a plurality of units from a common bar or rigging if this is desired.

Also shown in Figure 2 are an optional carrying handle 12 for ease of transfer and suspension of the unit, and a user input/output interface 14 and antenna 16, each of which may be used to control the output of the lighting unit as discussed below. A lamphouse 20 housing a light source (not shown) is tiltably coupled to one surface of the housing 10. Specifically, in this example the lamphouse is mounted on a yoke 22, of substantially square 'U'-shape, that is coupled to the surface of the housing by means of a suitable screw 24 or by any other appropriate fixing means, such as a nut-and-bolt arrangement. The lamphouse is configured to receive, at opposite ends of one diameter, suitable pins 26 or other coupling means that pass through the upper ends of the yoke to hold the lamphouse in place within the yoke. Thus, the lamphouse may tilt relative to the housing, such that the lighting unit may direct light to the desired area or spot within a venue. Moreover, in this instance the yoke 22 is also itself rotatable around the screw 24 for increased freedom of movement and range of directionality of the lamphouse, though this is not essential. Further, in other embodiments any suitable alternative arrangement, such as a ball joint, could be used to realise both tilting and rotational degrees of freedom of the lamphouse with respect to the surface of the housing.

As shown, the lamphouse in this embodiment further includes a heatsink 28 for dissipating the heat generated by the light source and is mounted within the yoke such that, when the lamphouse is in an upright position, there is a space between the base of the heatsink and the top surface of the housing 10. This ensures ease of movement of the lamphouse through a wide range of angles as well as efficient radiation of heat away from the heatsink.

Figure 3A shows the underside of the lighting unit 1 of the embodiment shown in Figure 2. A four-pin power connector 1 1 is provided towards one corner of the base of the housing, by means of which the battery may be charged without needing to be removed from the housing. For example, the battery could be charged by means of a suitable power cable that connects the unit to a mains power supply. Alternatively, the unit as a whole may be placed in a suitable charging dock or cradle, which may optionally be configured for charging a plurality of lighting units such as the unit 1 simultaneously. In this case, the battery may connect automatically to a charge supply connector when the unit is positioned in the dock. Thus, in this embodiment the lower portion of the housing 10 can also be sealed as described above to isolate the components internal to the housing from the external environment. In this example, the battery is an 18 V lithium iron phosphate battery having a capacity of 10 Ah. As mentioned above, batteries of this chemistry are

advantageous in terms both of the achievable runtime of the lighting unit and of the usable service lifetime of the battery itself. In this example, when used in conjunction with an LED light source such as that described below, the battery may power the unit for around 7 hours or more between charges, and may furthermore be capable of around 2000 or more charge/discharge cycles. Thus, the lighting unit may be economically efficient to use, in addition to having a comparatively low environmental impact. The recess in which the power connector is provided is preferably made of stainless steel, so as to be

advantageously resistant to wear as the battery is repeatedly charged.

In other embodiments, however, any other suitable battery or combination of batteries could be used as desired. Furthermore, whilst it is preferable to configure the lighting unit of the invention such that the battery may be charged within the housing as described, this is not essential.

Further shown in Figure 3A are four optional rubber feet 13 for stabilising the unit when it is used in a standing position as an uplighter, and a detachable bracket 15 that is removably fixed to the underside of the unit by means of two suitable screws 17 for use in hanging the unit upside-down from a suitable bar, rail or any other supporting means that may be available at an event venue. Specifically, a centre portion of the bracket includes a hole 19 for attaching any suitable clamp or clasp for suspending the unit from supporting means as required. Figure 3B shows the lighting unit 1 of the present embodiment in use with one such clamp 30, which does not form part of the invention. As can be seen in Figures 3A and 3B, the central portion of the bracket 15 is separated from the underside of the lighting unit, for ease of attachment of the clamp. The bracket 15 in this embodiment is made of steel, though any other meta! or suitable material could be used. Furthermore, as will be apparent to the skilled person, whilst in this example it is the underside of the unit 1 that is configured to receive the bracket 15, and thus to be coupled to suspension means in the form of a clamp such as that shown in Figure 3B, this is not essential. In other

embodiments, any of the other main surfaces of the housing could be configured in a similar way such that the preferred hanging arrangement may be realised. Figure 4 is an exploded view of the lamphouse 20 of the lighting unit 1. As shown, the lamphouse includes a recess 200 coupled to the heatsink 28. In this embodiment, the lamphouse recess and heatsink are fabricated from machined aluminium which, as is known to those in the art, may provide advantageous thermal properties at a comparatively low cost. In alternative embodiments, however, any other material having a suitably high thermal conductivity such as an aluminium alloy or copper could be used. Furthermore, the heatsink is of a standard construction, known to those of skill in the art.

In use, a printed circuit board 210, which includes a light source 215, and a collimator 220 are mounted in the recess 200, and are held in place by means of a fused quartz lens 230, which may improve the optical characteristics of the lighting unit, an optional silicone or rubber seal 240 and an aluminium bezel 250, which is fixed to the body of the lamphouse by screws 255 or other suitable fixing means. Thus, similar to the housing 10 described above, in this example the lamphouse may be sealed against external contamination to prevent any damage to the light source components.

In this embodiment, the light source 215 is a 40W multi-chip LED light source. As discussed above, LEDs are preferred over more conventional lamps in view of their comparatively low power requirements and long service lifetimes. Other embodiments, however, may use a fluorescent or incandescent light source, as desired. Moreover, whilst it is presently preferred to use a multi-chip LED package such as that shown in Figure 4, as discussed above, this is not essential, and in still further embodiments a single LED may be used, or alternatively a plurality of LEDs may be arranged as a distributed array.

In this example, the circuit board 210 is configured to operate as a driver for the LED light source 215 and is powered by means of an eight core supply cable, not shown in the drawings, that exits the housing 10 through a cable gland coupled to the surface of the housing, passes through the fin arrangement of the heatsink 28 into the recess 200 of the lamphouse and is connected directly to the circuit board 210. The cable is also configured to carry control signals for the light source, as described below.

Furthermore, the lighting unit 1 according to the present embodiment is configured as a multi-colour light. Thus, the LED package 215 includes LEDs having a range of output wavelengths, the circuit board 210 being further arranged as a colour mixing regulator circuit that controls the output of the light source in response to input from a user.

Specifically, the light source 215 includes LEDs emitting each of red, blue, green and white light. As shown in Figure 2, the lighting unit 1 includes a five-button keypad and an LED output display arranged as user input/output interface 14 on one surface of the housing, which may be used to turn the unit on or off, to program or to access pre-set modes of operation, or otherwise to configure or customise the unit for a user's particular application requirements. In addition and as mentioned above, an antenna 16 included on the housing 10 is configured to receive radio frequency remote control signals, such as DMX signals, from a compatible wireless transmitter. Returning to Figure 4, these control signals are relayed to the printed circuit board 210 through the cable that passes from the housing to the lamphouse as described above to adjust the output intensity of various LEDs within the light source 215 and, thus, the colour and intensity of the light output by the lighting unit. Though the antenna 16 in the embodiment of Figure 2 is arranged on the upper surface of the housing 10, in alternative embodiments the antenna could instead be positioned on any of the other main surfaces of the housing as desired and as appropriate, as will be clear to those of skill in the art.

Though not essential, the lighting unit of the present invention preferably includes a detachable barndoor accessory for increased control in shaping the light beam of the lighting unit. Figures 5A and 5B illustrate one example of such a shutter attachment 40 in an open and a closed configuration, respectively. As shown, the barndoor 40 includes a bezel 42 of a substantially flat, annular shape that is attached to the lamphouse of the lighting unit by means of suitable clips 44. Four articulated doors or wings 46 are coupled to the front of the bezel via hinges 48. In use, these wings are positioned by the user to shape and direct the light beam as desired. For instance, the wings may be arranged so as to exclude a specific area within a generally lit space from illumination. As discussed above, the ability to control and to direct the light emitted is particularly advantageous in the case of a lighting unit that is to be used in a hanging configuration, where it may not be easy or even possible to alter the position in which the unit itself is arranged. The barndoor 40 in this example is made of anodized aluminium, though any other suitable material could be used. Furthermore, other examples may make use of a magnetic arrangement instead of the clips 44 to attach the barndoor to the front of the Iamphouse. In addition, whilst the wings 46 are each shown in Figure 5A as having a substantially trapezoidal shape that widens with distance from the bezel, in other examples other shapes or combinations of shapes could be used as appropriate for a particular application.Thus, the invention combines means for affixing a suspension arrangement, a lightweight battery and a wireless control arrangement to provide a lighting unit capable of total wireless operation that is suitable for use in a hanging configuration.