H:\eb\Interwoven\NRPortbl\DCC\EB\61674901. DOCX- 08/04/2014 LIGHTING APPARATUS Background of the Invention [0001] The present invention relates to a portable lighting apparatus and to a method of forming a portable lighting apparatus. Description of the Prior Art [0002] 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 the 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. [0003] Lighting towers provide relatively portable lighting for situations where sufficient lighting is not available, for example, for night construction or mining operations. Typically a lighting tower has a lighting unit, a mast to position the lighting unit, and a power source to power the lighting unit. [0004] AU2010291868 describes a mobile lighting apparatus, including a base, traction means connected to the base and engaging the ground for moving the base, traction drive means connected to the traction means driving the traction means along the ground; a turret mounted on the base for rotating movement relative thereto about a vertical axis, turret drive means for driving the turret about the vertical axis, electricity generation means mounted to the turret for rotating movement therewith; an extendable boom pivotally mounted to the turret adjacent its proximal end for movement relative thereto between a lowered position and a raised position; lighting means connected to the boom at its distal end, and electricity communication means connecting said lighting means to said electricity generation means. [0005] This is a driven arrangement, requiring traction drive means in addition to electrical generation means, making this heavy and difficult to manoeuvre. Additionally, the arrangement typically uses high-power incandescent bulbs, requiring a large amount of power to operate, making this an extremely inefficient arrangement.
H:\eb\Interwoven\NRPortbl\DCC\EB\6167490_1.DOCX-08/04/2014 -2 [0006] AU2011100774 describes a portable lighting tower including a permanent magnet DC alternator directly driven by an air-cooled diesel engine. The portable lighting tower includes a scissor lift having LED (Light Emitting Diode) lamp arrays mounted at a distal end thereof. [0007] However, the use of a scissor lift severely limits the degree of manoeuvrability of the lighting array, thereby limiting use in a practical arrangement. [0008] AU2013100095 describes a lighting tower having a low voltage alternator, typically approximately 24V, powering an LED lighting unit. The alternator is a direct drive alternator connected directly to a small block diesel engine. The lighting tower is entirely low voltage reducing electrocution and ignition risks, and is highly efficient through the use of LED elements in the LED lighting unit and the efficient direct drive alternator. Summary of the Present Invention [0009] In one broad form the present invention seeks to provide a mobile lighting apparatus including: a) a trailer having a frame; b) a DC generator mounted to the trailer; c) a crane including: i) a mounting coupled to the trailer; ii) a boom having a number of boom sections, the boom extending from a proximal end supported by the mounting to a boom head; iii) an actuating mechanism for lifting and/or extending the boom sections; and, d) a lighting unit including an array of LEDs electrically coupled to the generator, the lighting unit being mounted to the boom head. [0010] Typically the apparatus includes: a) crane stabilizing legs coupled to the mounting for engaging a support surface to thereby support the crane; b) wheels or skids; c) a tow hitch coupled to the frame for towing the trailer; d) trailer stabilizing legs for engaging a support surface to thereby stabilise the trailer.
H:\eb\Interwoven\NRPortbl\DCC\EB\6167490_1.DOCX-08/04/2014 -3 [0011] Typically the actuating mechanism includes: a) hydraulic actuators; b) a hydraulic pump for supplying pressurized hydraulic fluid to the crane; and, c) controls for controlling the actuators to thereby adjust a position of the boom head; [0012] Typically at least one of: a) the DC generator includes: i) an engine; ii) an alternator rotationally coupled to the engine for generating a low or extra low DC voltage; and, b) a hydraulic pump rotationally coupled to the DC generator; c) the apparatus for includes a voltage regulator for regulating the DC voltage; and, d) the lighting unit includes thermal protection to prevent overheating of the lighting unit, the thermal protection including cooling fans or heat sinks. [0013] In another broad form the present invention seeks to provide a method of manufacturing a lighting unit the method including: a) providing a trailer having: i) a frame; ii) a DC generator mounted to the trailer; b) coupling a crane to the trailer, the crane including: i) a mounting coupled to the trailer; ii) a boom having a number of boom sections, the boom extending from a proximal end supported by the mounting to a boom head; iii) an actuating mechanism for lifting and/or extending the boom sections; and, c) mounting a lighting unit including an array of LEDs electrically coupled to the generator, the lighting unit being mounted to the boom head. Brief Description of the Drawings [0014] An example of the present invention will now be described with reference to the accompanying drawings, in which: - H:\eb\Interwoven\NRPortbl\DCC\EB\6167490_1.DOCX-08/04/2014 -4 [0015] Figure 1A is a schematic side view of an example of a lighting apparatus with a boom in a stowed position; [0016] Figure 1B is a schematic rear view of the lighting apparatus of Figure 1A; [0017] Figure 1C is a schematic side view of the lighting apparatus of Figure 1A with the boom in a partially deployed position; [0018] Figure 1D is a schematic rear view of the lighting apparatus arrangement of Figure 1C; [0019] Figure 1E is a schematic side view of the lighting apparatus of Figure 1A with the boom in a fully deployed position; [0020] Figure iF is a schematic rear view of the lighting apparatus arrangement of Figure 1E; [0021] Figure 1G is a schematic side view of the lighting apparatus of Figure 1A with the boom in a fully deployed position; [0022] Figure 1H is a schematic plan view of an example of the lighting unit; [0023] Figure 2 is a schematic diagram of the electrical and hydraulic systems of the lighting apparatus of Figure 1A; [0024] Figure 3 is a schematic side view of a second example of a lighting apparatus with a boom in a stowed position; and, [0025] Figure 4 is a schematic side view of a third example of a lighting apparatus with a boom in a stowed position. Detailed Description of the Preferred Embodiments [0026] An example of a lighting apparatus will now be described with reference to Figures 1A to 1H. [0027] In this example, the lighting apparatus 100 includes a trailer 110 having a frame 111 and a DC generator 200, mounted to the trailer, for example by mounting the generator 120 to the frame 111, and may be provided in a housing 112. The DC generator 200 is typically a low, and more typically an extra low voltage DC generator for generating a voltage in the region of -24V as will be described in more detail below.
H:\eb\Interwoven\NRPortbl\DCC\EB\6167490_1.DOCX-08/04/2014 -5 [0028] A crane 120 is provided including a mounting 121 coupled to the frame, a boom 122 having a number of boom sections 122.1, 122.2, 122.3, 122.4, 122.5, with five being shown in this example for the purpose of illustration only. The boom 122 extends from a proximal end supported by the mounting 122 to a boom head 123 at a distal end, with an actuating mechanism being provided for lifting and/or extending the boom sections. [0029] A lighting unit 130 including an array of LEDs being mounted to the boom head 123, with the LED array being electrically coupled to the DC generator, thereby allowing the LEDs to be powered. [0030] Accordingly, in this arrangement, a crane is used to support an LED lighting array, allowing this to be moved from a stowed position shown in Figures 1A and 1B, through progressive stages of deployment, as shown for example in Figures 1C and 1D, 1E and iF, and 1G. As part of this, in one example, the boom 122 can be rotatably mounted to the mounting 121 to allow for up to 4000 rotation relative to the trailer, thereby allowing the boom to provided at a range of different angles relative to the trailer. This provides a lighting apparatus with a high degree of flexibility compared to many existing arrangements. In particular, this allows the lighting unit to be provided in a raised position, as well as being laterally offset from the trailer 110, for example, allowing this to extend and provide illumination over a wall or other similar obstacle. [0031] In one example, the crane can provide a reach extending over 10m and more typically 18m or more, which is not achievable by other towed units in wheeled or skid formats. Additionally, the crane typically includes in built safety mechanisms that prevent the crane from lifting the lighting unit about the operator controls, thereby preventing accidental misshap that could lead to injury of the operator. [0032] Furthermore, in this arrangement, the system uses LEDs that have a low and optionally extra low power consumption, thereby minimizing the power that needs to be generated. This allows the fuel usage to be minimized, allowing lighting to be provided for long durations without requiring re-fueling. For example, the arrangement can be fitted with a fuel tank with a capacity such as 215 liters, allowing for over 10 days operation, and 440 H:\eb\Interwoven\NRPortbl\DCC\EB\6167490_1.DOCX-08/04/2014 -6 liter for up to one month of continuous operation without refueling. However, it will be appreciated that any suitable capacity could be used. [0033] The trailer is typically adapted to be towed, dragged, or lifted into position using a crane or the like, thereby reducing the complexity of the apparatus compared to self propelled arrangements, and additionally minimizing the weight of the system, allowing this to be more easily and rapidly deployed. In one example, the arrangement as a weight of below four tons, although it will be appreciated that the actual weight will depend on the preferred implementation. [0034] A further benefit of the above arrangement is that the crane can be provided as a self contained unit, thereby allowing it to be mounted directly onto an existing trailer. In this example, the lighting apparatus can therefore be constructed by providing a trailer 110 having a frame and low voltage DC generator mounted to the frame. The crane 120 can then be attached to the frame, with the crane 120 including the mounting 121, boom 122, and actuating mechanism provided as integral components. [0035] Thus, it will be appreciated that this allows the configuration to be rapidly constructed from existing equipment, albeit with minor modifications to allow for suitable integration. [0036] A number of further features will now be described. [0037] In one example, the crane 120 includes crane stabilising legs 125 coupled to the mounting 121 for engaging a support surface to thereby support the crane, and hence stabilise the trailer during deployment and use of the lighting unit. This can assist in increasing the footprint of the lighting apparatus and assist in stabilising against wind loading or the like. The crane stabilising legs 125 can be of any form, but in one example includes arms 125.1 that extend outwardly from the mounting, being urged into position using a linear actuator. The crane stabilising legs 125 further include first and second leg portions 125.2, 125.3, with the first leg portion 125.2 being fixed to the arm 125.1, and the second leg portion 125.3 being telescopically coupled thereto. The second leg portion 125.3 supports a foot 125.4 that acts to distribute the load of the crane. Accordingly, it will be appreciated that the arms 125.1 can be extended laterally outwardly to a suitable distance, before the second leg portion H:\eb\Interwoven\NRPortbl\DCC\EB\6167490_1.DOCX-08/04/2014 -7 125.3 is extended so that the foot 125.4 engages the ground, thereby supporting the weight of the lighting apparatus 100. [0038] The trailer can be of any suitable form, depending on the preferred implementation. In one example, the frame 111 includes elongate frame members 111.1 extending substantially along a length of the frame, with lateral connecting frame members 111.2 being coupled thereto. The frame members can be of any form, but typically include steel or aluminium beams or similar. [0039] In one example, the trailer includes wheels 114 and a tow hitch 111.3, coupled to the frame, thereby allowing the trailer 110 to be towed, although other arrangements, such as skid mounted trailers can be used as will be described in more detail below. The trailer may further include trailer stabilizing legs 113 for engaging a support surface to thereby help further stabilise the trailer. These can extend outwardly and along the trailer length, and swing into engagement with the ground, with the legs being locked into position as required and as shown in Figure 1C. [0040] The trailer 110 typically includes a housing 112 for containing components such as the generator and associated fuel tanks, the hydraulic pump, or the like, thereby protecting the components from the environment and preventing user's inadvertently coming into contact with the components. The housing 112 also typically supports a support cradle 114, which receives the lighting unit 130 when in the stowed position. This can support the weight of the lighting unit, acting to protecting the lighting unit and prevent undue stress on the boom 122 while the lighting apparatus is being transported. [0041] The lighting unit typically includes thermal protection to provide thermal management and prevent overheating of the lighting unit. The thermal protection can include cooling fans or heat sinks, although other arrangements could be used including liquid cooling or the like. Additionally, the lighting unit typically includes an array of LEDs mounted under a removable cover, allowing access to the LEDs and associated electronics, such as the thermal protection, emitter boards, drivers or the like, thereby allowing these to be easily repaired. The cover can also include optics for focussing the illumination emitted by the LEDs, depending on the preferred implementation. Additionally and/or alternatively H:\eb\Interwoven\NRPortbl\DCC\EB\6167490_1.DOCX-08/04/2014 the lighting unit or lights might also contain electronics to dissipate EMFs, and electrical interference(s) that may cause or have detrimental effects on the lighting system or the lights themselves. [0042] An example of the lighting unit is shown in Figure 1H. In this example, the lighting unit 130 includes three LED arrays 131.1, 131.2, 131.3. Although three are shown, this is not intended to be limiting and any number could be used. In this example, the arrays are provided on separate panels, which are provided at an angle relative to each other, thereby allowing the illumination to be guided. In a further example, the panels can be connected via hinges, allowing the relative angles of the arrays 131.1, 131.2, 131.3 to be adjusted. This can be used to allow the illumination provided by the panels to be concentrated into the same region, or dispersed more widely, thereby allowing differing extents and brightness of illumination to be obtained. In this example, the array 131.1 is coupled to the boom section 122.5 at the boom head 123 using suitable brackets 133 attached to the array 131.1, and coupled to the brackets 133 using a fastener, such as a bolt or the like, although other arrangements could be used. [0043] Additionally, the arrays 131.1, 131.2, 131.3 can be controlled or manoeuvred electrically or hydraulically, using actuators to allow for adjustment of the illumination once provided in a deployed position. This can be used to adjust the relative angle of the arrays 131.1, 131.2, 131.3, as well as to tilt the arrays 131.1, 131.2, 131.3 relative to the boom head, thereby allowing an operator to perfect or improve light delivery to a work area. This may also be carried out using either electrical or manual controls, and in a further example could be performed remotely of the lighting apparatus, for example using a suitable electronic controller, or device able to communicate with an onboard controller. Being able to adjust the lighting unit and/or boom remotely allows a user to stand apart from the lighting apparatus, for example in the area to be illuminated, thereby making it possible for the user to more easily optimise the or using remote control of operation, which can be important if the operator is unable to view the area being illuminated from the trailer. [0044] The actuating mechanism for the boom and/or lighting array could be of any suitable form and could include mechanical linkages, cable and pulley systems, pneumatic arrangements, electric motors, or the like. In one particular example, the actuating H:\eb\Interwoven\NRPortbl\DCC\EB\6167490_1.DOCX-08/04/2014 -9 mechanism includes hydraulic actuators 124, a hydraulic pump for supplying pressurized hydraulic fluid to the actuators and controls for controlling the actuators to thereby adjust a position of the boom head. The controls can be of any suitable form, and can include manual controls, such as levers or buttons for operating control valves, or could include an electronic control system, optionally including a remote control capabilities. [0045] A hydraulic pump can be rotationally coupled to the generator, for example using a drive belt or the like, with this being coupled to a hydraulic fluid inlet and return outlet of the crane, allowing the crane hydraulics to be powered by the generator. This arrangement further improves efficiency, for example by converting rotational energy directly into hydraulic pressure, rather than converting this to electricity, and then using the electricity to power a hydraulic motor. [0046] An example of the configuration or the electrical and hydraulic circuits will now be described in more detail with reference to Figure 2. [0047] In this example, the voltage DC generator 200 includes an engine 201, such as a combustion, and more typically a diesel or gas powered engine (LPG, LNG, hydrogen), that is rotationally coupled to the alternator for generating a low DC voltage, typically less than 48V, and more typically an extra-low voltage in the range of 20-28V and optionally about 24V. In one example, the engine 200 drives a drive shaft 202, with the alternator 203 being directly coupled to the drive shaft. However, this is not essential and other rotational drive mechanisms can be used, such as belt and pulley arrangements or the like. [0048] The alternator is optionally coupled to a regulator 204, for regulating or conditioning the power supplied to the lighting unit. The regulator is generally adapted to buffer the lighting unit 130 from voltage spikes, for example caused by EMFs in the cabling along the boom, or voltage drops along the cable. In this regard, to accommodate extension of the boom, the lighting unit is typically coupled to the generator by a fifteen meter cable, in which 2 2 case the cable has a suitable cross section, such as at least 70 mm and optionally 95 mm , or another suitable value, to thereby minimise voltage drops along the cable. In any event, the voltage regulator protects the lighting unit 130 from damage and ensuring consistent illumination. This can be achieved using a variety of mechanisms, such as using a capacitor H:\eb\Interwoven\NRPortbl\DCC\EB\6167490_1.DOCX-08/04/2014 - 10 provided in parallel with the generator output, or alternatively could involve using a battery, with the generator charging the battery, and the battery being used to provide a consistent supply to the lighting unit. It will be appreciated however than any suitable regulating or voltage conditioning mechanism could be used. [0049] The lighting apparatus typically includes a hydraulic pump 210, which is rotationally coupled via hydraulic connections to a hydraulic system 220 of the crane 120. The hydraulic pump 210 is rotationally driven by the engine 201, for example via a drive belt 212, entrained round a pulley 211 on the shaft 202, and a second pulley 213 coupled via a drive shaft 214 to the hydraulic pump 210, although other arrangements such as direct drive by the drive shaft could be used. [0050] In this example, the hydraulic system 220 of the crane 120 includes a number of flow control valves (not shown) for controlling the supply of hydraulic fluid to actuators 222.1, 222.2, 222.3, such as hydraulic pistons, rams or cylinders used for the controlling the boom 122. The valves can be controlled by a controller 221, which can including manual control inputs, such as buttons or levers, or alternatively can include an electronic controller including a processing device such as a microprocessor, microchip processor, logic gate configuration, firmware optionally associated with implementing logic such as an FPGA (Field Programmable Gate Array), or the like. In this case, the controller could include an input/output, such as a touchscreen, display and input buttons or the like, allowing operation of the boom and/or crane stablising legs to be controlled. Additionally and/or alternatively, a remote control unit can be provided. In one example, the remote control unit interfaces with an in-built electronic controller, and it will therefore be appreciated that this could be achieved using any suitable device that is capable of interacting with the controller, such as a suitably programmed Smartphone or the like. [0051] It will be appreciated that a wide variety of different configurations could be used. For example, the lighting apparatus could be a single axle arrangement, or could include skids instead of wheels as shown in Figure 3. In this example, similar reference numerals increased by 200 are used to refer to similar components to the example of Figure 1A and these will not therefore be described in further detail. In this example however, the wheels are replaced by skids 314, allowing the lighting apparatus to be dragged, lifted, pushed or H:\eb\Interwoven\NRPortbl\DCC\EB\6167490_1.DOCX-08/04/2014 - 11 otherwise manoeuvred into a desired position, as will be appreciated by persons skilled in the art. [0052] A specific example of a lighting apparatus is shown in Figure 4. [0053] In this example, the lighting apparatus is similar to that described in AU2013100095 and includes a tandem axle chassis 410 that includes wheels 412, front stabilising legs 414 and a towing attachment 418. However, a single axle, dog trailer or semi trailer arrangement could be used and this is not intended to be limiting. The lighting tower 400 has an engine module 420 and hydraulic module 422 having respective cover members in the form of service hatches 420' and 422'. Both the engine module 420 and hydraulic module 422 of the lighting tower 100 are replaceable if needed. [0054] In AU2013100095 a mast is provided on top of the hydraulic module 422. In this example, instead a crane 424 with LED lighting unit 126 mounted at a distal end thereof is provided on the chassis 410 adjacent the engine module, and at the opposite end of the chassis to the towing arrangement 418. [0055] In this example, the lighting apparatus includes an engine connected directly via a common axially aligned shaft to an alternator. The engine is a small block diesel engine, preferably a 2 cylinder Kubota or 1 cylinder Hatz engine. The alternator is preferably a Linz 24V 200A or greater, or Sincro 24V 200A alternator which may be modified by bridging thermal switches thereon. The hydraulic module includes a hydraulic pump physically coupled to the shaft so that the pump is operated by the engine. Alternatively, a remote self contained electrical powered pump or hydraulic system could be used. [0056] The LED lighting units comprise a plurality of 24V LED light assemblies and are each made up of two dimensional arrays of LED elements. The LED elements may have their own optical elements, e.g. reflectors and/or lenses, in order to provide the best light output for the desired application, and may be angled or have different optics to allow for selective illumination. Additionally, the lighting units can include thermal protection to protect from overheating due to extreme power usage, as well as electrical protection to protect against over voltages, EMFs or the like. Additionally, the LEDs and/or associated electronics can be repairable to allow for maintenance to be performed.
H:\eb\Interwoven\NRPortbl\DCC\EB\61674901. DOCX- 08/04/2014 - 12 [0057] The alternator provides DC power, preferably 24V, to the LED lighting unit 526. Additional components can be provided, such as a Zener diode connected in series with the LEDs or capacitors connected in parallel, to provide a stable power supply to the LEDs for example by smoothing out fluctuations, such as power spikes, caused by the alternator and/or EMF induced by cabling between the alternator and the LED lighting unit. [0058] In one specific example, the crane is in the form of a PM 8024 or other similar arrangement. It will be appreciated however that this is not intended to be limiting. [0059] Accordingly, the above lighting arrangements are portable, energy efficient, self sufficient lighting sources that can be temporarily, or permanently, arranged to provide light to an area to be illuminated. The LED lighting unit 126, 226 is not only energy efficient, but also operates on a lower, much safer, voltage (e.g. 24V DC) than previous lighting towers. Individual optical elements for the LED elements enhances the usable light from the LED elements by directing the light in an optimal manner for the task at hand, ensuring lighting power is not lost through poor optical management as can occur when all of the elements have the same optical characteristics. [0060] Furthermore, the direct drive 24V alternator ensures the entire system operates at low voltage, without any high to low voltage conversion, while also reducing maintenance, servicing requirements, and efficiency losses by avoiding indirect mechanical coupling systems such as a belt between the engine and alternator. [0061] The lower power requirements for similar illumination means that smaller, more portable units can be provided than was previously possible while also reducing capital costs, maintainence fuel consumption or refueling, and carbon emissions. [0062] Throughout this specification and claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers or steps but not the exclusion of any other integer or group of integers. [0063] Persons skilled in the art will appreciate that numerous variations and modifications will become apparent. All such variations and modifications which become apparent to H:\eb\Interwoven\NRPortbl\DCC\EB\6167490_1.DOCX-08/04/2014 - 13 persons skilled in the art, should be considered to fall within the spirit and scope that the invention broadly appearing before described.