AU2012201807A1 - Mobile lighting apparatus - Google Patents

Abstract

Mobile lighting apparatus, including: a steerable vehicle having a body supported on a pair of spaced apart rear wheels and a pair of spaced apart front 5 wheels; drive means operatively connected to at least one of said pair of rear wheels and said pair of front wheels for driving the vehicle along the groAnd; an extendable boom pivotally mounted to said body at or 10 near its rear end for movement relative Lherebo between a lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear wheels; lighting means operatively connected to said boom at or 15 adjacent its end distal from said vehicle body; electricity generation means mounted to said vehicle body behind said extendable boom adjacent its proximal end; and electricity communication means connecting said electricity generation means to said lighting means. n'2 (33

Description

MOBILE LIGHTING APPARATUS This invention relates to mobile lighting apparatus. The invention has particular application to mobile lighting apparatus of the type in which an array of lights is mounted 5 to a boom which can be raised when in a desired location for directing light onto a selected area and lowered for transport to another desired location or site. One known mobile lighting apparatus includes a trailer with a boom and an array of lights mounted thereon which can be 10 raised from a lowered position in which the boom is horizontal and can be secured in the horizontal position to a raised or elevated position in which the boom is vertical and can be secured in the raised position. Such apparatus provides for operation of the lights only when the boom is in the vertical 15 position and provides for securement of the boom only in the horizontal and vertical positions. The present invention is aimed at providing mobile lighting apparatus which can be more easily moved than a trailer from one site to another. The invention is also aimed at providing 20 mobile lighting apparatus which can supply more powerful lighting than previously known mobile lighting apparatus. The invention is also aimed at providing mobile lighting apparatus in which the lights can be operated in a large range of positions. 25 Summary of the invention With the foregoing in vicw, the present invention resides broadly in mobile lighting apparatus, including: a steerable vehicle having a body supported on a pair of 30 spaced apart rear wheels and a pair of spaced apart front wheels; c)DNO5 13 2 drive means operatively connected to at least one of said pair of rear wheels and said pair of front wheels for driving the vehicle along the ground; an extendable boom pivotally mounted to said body at or 5 near its rear end for movement relative thereto between a lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear wheels; lighting means operatively connected to said boom at or 10 adjacent its end distal from said vehicle body; electricity generation means mounted to said vehicle body behind said extendable boom adjacent its proximal end; and electricity communication means connecting said electricity generation means to said lighting means. 15 In another aspect, the invention resides broadly in mobile lighting apparatus, including: a steerable vehicle having a body supported on a pair of spaced apart rear wheels and a pair of spaced apart front wheels; 20 drive means operatively connected to at least one of said pair of rear wheels and said pair of front wheels for driving the vehicle along the ground; an extendable boom pivotally mounted to said body at or near its rear end for movement relative thereto between a 25 lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear wheels; lighting means operatively connected to said boom at or adjacent its end distal from said vehicle body; 30 electricity generation means mounted to said vehicle body beside said expendable boom adjacent its proximal end; and cJONG5134 3 electricity communication means connecting said lighting means to said electricity generation means. In yet another aspect, the invention resides broadly in mobile lighting apparatus, including: 5 a steerable vehicle having a vehicle body supported on a pair of spaced apart rear wheels and a pair of spaced apart front wheels; drive means operatively connected to at least one of said pair of rear wheels and said pair of front wheels for driving 10 the vehicle along the ground; an extendable boom pivotally mounted to said body at or near its rear end for movement relative thereto between a lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical 15 plane relative to the rear wheels; lighting means operatively connected to said boom at or adjacent its end distal from said vehicle body; electricity generation means including an internal combustion engine having an alternator or generator coupled 20 thereto mounted to said vehicle body behind said extendable boom; electricity communication means connecting said electricity generation means to said lighting means for transmitting electricity thereto for powering said lighting means; and 25 electrical ballast in electrical communication with said lighting means and said electricity generation means, said ballast being mounted to said vehicle body in a substantially closed chamber remote from said lighting means, said chamber having an air inlet and an air outlet and air supply means for 30 causing air flow through said chamber from said air inlet to said air outlet to cool said ballast. cJONOS 134 4 In yet another aspect, the invention resides broadly in mobile lighting apparatus, including: a steerable vehicle having a vehicle body supported on a pair of spaced apart rear wheels and a pair of spaced apart 5 front wheels; drive means operatively connected to at least one of said pair of rear wheels and said pair of front wheels for driving the vehicle along the ground; an extendable boom pivotally mounted to said body at or 10 near its rear end for movement relative thereto between a lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear wheels; lighting means operatively connected to said boom at or 15 adjacent its end distal from said vehicle body; electricity generation means including an internal combustion engine having an alternator or generator coupled thereto mounted to said vehicle body substantially on one side of said extendable boom; 20 electricity communication means connecting said electricity generation means to Said lighting means for transmitting electricity thereto for powering said lighting means; and electrical ballast in electrical communication with said lighting means and said electricity generation means, said 25 ballast being mounted to said vehicle body in a substantially closed chamber remote from said lighting means, said chamber having an air inlet and an air outlet and air supply means for causing air flow through said chamber from said air inlet to said air outlet to cool said ballast. 30 Preferably, said air supply means includes a blower arranged to suck air through a dust filter before entering the chamber via said air inlet. Advantageously, such arrangement prevents the build up of coal dust or other explosive material cJ0NOS5134 S in the ballast chamber. The blower could be arranged on the inlet side of the chamber or the outlet side but preferably, it is arranged on the inlet side downstream of the filter. In such arrangement, air leaving the chamber will be filtered air 5 and preferably the flow rate of air leaving the chamber via the outlet is sufficient to prevent the ingress of dust therethrough. Advantageously, the separation of the ballast from the lighting means allows for relatively easy maintenance of the 10 ballast at ground level and also allows the ballast to be housed in a relatively dust proof chamber through which filtered air can be passed thereby increasing ballast life and improving operational safety especially when used in coal mining operations. 15 Preferably, said electricity communication means includes a power cable arranged to fold and unfold on a tray or rack mounted to said boom as said boom retracts and extends. Preferably, said electricity generation means includes an internal combustion engine and an alternator or generator 20 coupled thereto. It is also preferred that said electricity generation means be mounted on a platform which overhangs said body such that in use, the platform is closer to the ground than the body such that in cases where the wheels sink into the ground the platform engages the ground and supports the 25 body thereby keeping the electricity generation means above ground level. Preferably, said drive means includes an engine and gearbox or one or more hydraulic motors drivingly connected to the wheels independently of the electricity generation means. In 30 a preferred form the drive means is arranged for fairly high road speed travel, above about 30kmph. It is also preferred that the drive means be mounted on the side of the boom opposite to the electricity generator means to balance the WONOS 134 6 vehicle and together therewith provide a suitable counterweight for the boom. Advantageously, such arrangement allows the apparatus to be quickly taken to a site in an emergency situation. $ In yet another aspect, the invention resides broadly in a method of converting a' vehicle to lighting apparatus as previously described, the vehicle being a steerable vehicle having a vehicle body supported on a pair of spaced apart rear wheels and a pair of spaced apart front wheels and drive means 10 operatively connected to at least one of said pair of front wheels and said pair of rear wheels for driving the vehicle along the ground, an extendable boom pivotally mounted to said body at or towards the rear of the vehicle body for movement relative thereto between a lowered position and a raised 15 position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear wheels, the method including: mounting electricity generation means to said vehicle body in a predetermined position behind said boom, said electricity 20 generation means including an alternator or generator driven by a second internal combustion engine; connecting lighting means to said boom at or adjacent its distal end; and electrically connecting said electricity generation means 25 to said lighting means. In still yet another aspect, the invention resides broadly in a method of converting a vehicle to lighting apparatus as previously described, the vehicle being a steerable vehicle having a vehicle body supported on a pair of spaced apart rear 30 wheels and a pair of spaced apart front wheels and drive means operatively connected to at least one of said pair of front wheels and said pair of rear wheels for driving the vehicle along the ground, an extendable boom pivotally mounted to said CJON05 1341 7 body at or towards the rear of the vehicle body for movement relative thereto between a lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear 5 wheels, the method including: locating said drive means on said vehicle body in a first predetermined position substantially on onc side of said boom and mounting electricity generation means to said vehicle body in a second predetermined position substantially on the 10 opposite side of said boom, said electricity generation means including an alternator or generator driven by an internal combustion engine; connecting lighting means to said boom at or adjacent its distal end; and 15 electrically connecting said electricity generation means to said lighting means. Preferably, said first and second predetermined positions are selected such that the electricity generation means and the drive means act as suitable counterweights for the boom 20 and the lighting means mounted thereon when fully extended and are arranged to laterally balance the vehicle. In one form of the invention where the vehicle has a counterweight mounted to the vehicle body, the method includes removing the counterweight and instead utilising the combination of the 25 electricity generation means and the drive means as the counterweight". Preferably, the method also includes mounting electrical ballast in a chamber in or on said vehicle body, said chamber having an air inlet and an air outlet and air supply means for 30 causing air flow through said chamber from said air inlet to said air outlet to cool said ballast and connecting said ballast to said lighting means and said electricity generation means for electrical communication therewith. eJ0oso13 8 Preferably, said first and second predetermined positions are selected such that said traction drive means and said electricity generation means substantially balance each other on opposite sides of said boom. Suitably, balancing the 5 traction drive means and the electricity generation means improves the stability of the apparatus. The terms "horizontal" and 'vertical" are intended to describe the orientation of the particular axis or component being referred to when the apparatus is at rest on a level 10 horizontal surface even though the axis or component may not be geometrically exactly vertical or horizontal. Further, such terms are not intended to limit the apparatus to use in any particular orientation. In order that the invention may be more easily understood 15 and put into practical effect, reference will now be made to the accompanying drawings wherein: Fig. 1 is a perspective view of lighting apparatus according to the invention from the front towards one side with the boom in the fully lowered and retracted position; 20 Fig. 2 is a perspective view of the apparatus of Fig. 1 from the rear towards the other side with the boom in the same position; Fig. 3 is a perspective. view of the apparatus of Fig. 1 from the front towards one side with the boom in the fully raised position 25 and fully retracted; Fig. 4 is a perspective view of the apparatus of Fig. 1 from the same position as in Fig. 3 with the boom in the fully raised position and fully extended; Fig. 5 is a perspective view of another lighting apparatus 30 according to the invention from the front towards one side with the boom in the almost fully lowered and retracted position; WONO5134 10 of the two halves is achieved by hydraulic rams as is known in relation to cranes and similar vehicles. An extendable boom 21 is mounted to the body for up and down movement about a horizontal pivot pin 22 (which is hidden 5 behind body panels in the drawings) in known manner for apparatus of this type so that the boom can be raised and lowered with its longitudinal axis 23 remaining generally in the same vertical plane. The drive engine also drives a hydraulic pump 17 (hidden in 10 the body) for supplying hydraulic fluid to the boom rams 18, 19 and 20 in known manner for raising and lowering and extending and retracting the boom 21 as will be understood by the skilled addressee. A lighting frame 31 having an array of lights 32 mounted 15 thereon is connected to the outer end 33 of the boom by a pivot pin 34 for up and down movement relative to the boom with the hydraulic ram 20 arranged to selectively raise and lower the frame. The lights in the array are powered by a diesel engine 20 driven generator unit 41 which is bolted to a support platform 42 extending from the rear of the body 11. Advantageously, the generator unit is mounted in a predetermined position so as to provide a suitable counterweight to the boom and the lighting frame as well as the frame and lights attached 25 thereto. A power cable 51 extends from the generator unit 41 along a cable rack 52 on the offside of the boom and is connected to a distribution box (not shown) mounted on the lighting frame 32. Smaller cables distribute power from the distribution box to 30 individual lights 32 mounted on the frame. In another embodiment of the invention having the same general appearance of the apparatus previously described, the lighting ballast 71 is separated from the lights 32 and is cJONOSI34 9 Fig. 6 is a perspective view of the apparatus of Fig. 5 from the rear towards the other side with the boom in the same position; Fig, 7 is a perspective view of the lower part of the apparatus 5 of Fig. 5 from the front with the boom in the fully raised position: Fig. 8 is a perspective view of the apparatus of Fig. 5 from the rear and to one side with the boom in the fully lowered position and fully retracted; Fig. 9 is a pictorial representation of the lighting 10 ballast cabinet in the apparatus of Fig. 5; and Fig. 10 is a circuit diagram showing the arrangement of the lighting ballast and the air flow safety switch for the ballast cabinet. The lighting apparatus 10 illustrated in Fig. 1 has been 15 converted from lifting apparatus according to one of the methods previously described. The lighting apparatus 10 includes a body 11 integrally formed with a chassis 12 which is supported on two spaced apart front wheels 13 and two spaced apart rear wheels 14 20 which are drivingly connected to a rear drive axle assembly in known manner for providing motive power to the wheels from the drive engine 15 and gearbox 16 mounted within the body 11. The front wheels are mounted on king pins or the like and are arranged to pivot about respective vertical (or near 25 vertical) axes through the king pins for steering the apparatus in known manner. However, in other forms of the invention, the body is an articulated body comprising a front half and a rear half which are connected by a vertical pivot pin arranged to allow the two halves to pivot relative to each 30 other about a vertical axis intermediate the two halves in known manner to steer the vehicle. In such case, the front and rear wheels are fixed to their respective halves and pivoting cJONI5 134 11 housed in a ballast cabinet 72 of the type shown in Fig. 9 which is mounted to the turret adjacent the generator unit 41. Advantageously, the cabinet has an air inlet 73 in the bottom wall of the cabinet (or in a side wall if more 5 convenient) and an air outlet 74 in the top wall or towards the top of a side wall or the rear wall if space demands such position provided the inlet and outlet are arranged to allow adequate circulation through the cabinet. Suitably, an air supply fan (or blower) 76 is connected to the air inlet by a 10 flexible duct 77 and is arranged to draw air in through a dust filter 78 and force it through the ballast cabinet to exhaust through outlet 74 and exhaust pipe 29 before discharging to atmosphere under cover 81 (shown schematically) , It will be appreciated that the air leaving the cabinet will be filtered 15 air and the flow rate of air leaving the chamber via the outlet will be sufficient to prevent the ingress of dust therethrough especially in view of the outlet being covered by hood 81. The fan is normally in the "on" position whenever the 20 generator is running in order to keep the ballast cool. In order to ensure against ballast failure, an air flow switch 82 is mounted in the exhaust pipe and arranged to open if the air flow falls below a predetermined rate selected to achieve the manufacturers temperature specification for the ballast and 25 shut down the generator unit and/or if desired activate a warning signal. The lighting apparatus 110 illustrated in Figs. 5 to 8 has been converted from lifting apparatus according to one of the methods previously described in much the same manner as the 30 apparatus shown in Fig. 1. As many of the features of apparatus of Fig. 5 are the same as in the apparatus of Fig. 1, the same reference numbers are used herein] for corresponding features where possible or desirable.

12 The lighting apparatus 110 includes a body 1l1 formed with a chassis 112 which is supported on two spaced apart front wheels 113 and two spaced apart rear wheels 114 which are drivingly connected to a rear drive axle assembly in known 5 manner for providing motive power to the wheels from the drive engine 115 and hydraulic pump which are mounted within the drive engine compartment 117 for driving the vehicle along the ground and for raising, lowering, extending and retracting the boom and for raising and lowering the outrigger legs 120. 10 The front wheels are -mounted on king pins 11.8 or the like and are arranged to pivot about respective verLical (or near vertical) axes through the king pins for steering the apparatus in known manner. An extendable boom 121 is mounted to the body for up and 15 down movement about a horizontal pivot pin 122 (which is hidden behind body panels in the drawings) in known manner for apparatus of this type so that the boom can be raised and lowered with its longitudinal axis 123 remaining generally in the same vertical plane. 20 A lighting frame 131 having an array of lights 132 mounted thereon is connected to the outer end 133 in the same manner as in Fig. 1. The lights in the array arc powered by a diesel engine driven generator unit 141 which is mounted on the other side 25 of the vehicle body opposite to the drive engine 115 immediately above the left hand side wheel arch. Advantageously, the generator unit is mounted on one side of the boom while the drive engine and hydraulic pump are mounted on the other side with the two units combined 30 providing a suitable counterweight for the boom and the lighting frame and lights mounted thereto while at the same time ensuring suitable lateral stability. cJONO3134 13 Advantageously, the ballast cabinet 171 is mounted on the same side and behind the drive engine immediately above the right hand side wheel arch in a relatively cool position and incorporates a cooling fan unit connected in much the same 5 manner as previously described. In use, when temporary lighting is required at a site, for example for machinery breakdown repairs, road works, sporting events and the like, the lighting apparatus can be driven to the site at a suitable road speed where the boom can be raised 10 and extended to a desired elevated position and the generator started to supply power to the lights. In the apparatus illustrated in Fig. 1 the generator unit has a 5ORVA generator and the array of lights take 24KW so it will be appreciated that the generator has sufficient capacity 15 to provide for a more powerful array of lights if desired. The boom of the apparatus illustrated is selected to be able to hold the array of lights at a height of approximately 20 metres above the ground. However, apparatus of greater or lesser lighting power and greater or lesser boom length could 20 be constructed if desired. The foregoing description has been given by way of illustrative example of the invention and many modifications and variations which will be apparent to persons skilled in the art may be made without departing from the spirit and 25 scope of the invention as defined by the appended claims. JONOMM31

Claims (25)

1. Mobile lighting apparatus, including: a steerable vehicle having a body supported on a pair of 5 spaced apart rear wheels and a pair of spaced apart front wheels; drive means operatively connected to at least one of said pair of rear wheels and said pair of front wheels for driving the vehicle along the ground; 10 an extendable boom pivotally mounted to said body at or near its rear end for movement relative thereto between a lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear wheels; 15 lighting means operatively connected to said boom at or adjacent its end distal from said vehicle body; electricity generation means mounted to said vehicle body behind said extendable boom adjacent its proximal end; and electricity communication means connecting said electricity 20 generation means to said lighting means.

2. Mobile lighting apparatus, including: a steerable vehicle having a body supported on a pair of spaced apart rear wheels and a pair of spaced apart front 25 wheels; drive means operatively connected to at least one of said pair of rear wheels and said pair of front wheels for driving the vehicle along the ground; an extendable boom pivotally mounted to said body at or 30 near its rear end for movement relative thereto between a lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear wheels; cJONOS 134 15 lighting means operatively connected to said boom at or adjacent its end distal from said vehicle body; electricity generation means mounted to said vehicle body beside said extendable boom adjacent its proximal end; 5 and electricity communication means connecting said lighting means to said electricity generation means.

3. Mobile lighting apparatus according to Claim 1 or Claim 2 10 wherein said electricity generation means includes an internal combustion engine and an alternator or generator coupled thereto.

4. Mobile lighting apparatus according to any one of the 15 preceding claims wherein said electricity generation means is mounted on a platform which overhangs said body such that in use, the platform is closer to the ground than the body whereby in use if the rear wheels sink into the ground the platform may engage the ground and support the body. 20

5. Mobile lighting apparatus according to any one of the preceding claims wherein said drive means includes an engine and gearbox or one or more hydraulic motors drivingly connected to the wheels independently of the electricity 25 generation means for road travel at speeds above about 30kph.

6. Mobile lighting apparatus according to any one of the preceding claims wherein said lighting means includes a frame having an array of lights mounted thereon. 30

7. Mobile lighting apparatus according to Claim 6 wherein said frame is operatively connected to said boom for up and down movement relative thereto. c)ONOi134 16

8. Mobile lighting apparatus according to Claim 7 including one or more hydraulic rams for causing up and down movement of said frame relative to said boom. 5

9. Mobile lighting apparatus according to any one of the preceding claims wherein said electricity communication means includes a cable extending along the side of the boom and connected to a distribution box mounted on the lighting frame. 10

10. Mobile lighting apparatus, including: a steerable vehicle having a vehicle body supported on a pair of spaced apart rear wheels and a pair of spaced apart front wheels; 15 drive means operatively connected to at least one of said pair of rear wheels and said pair of front wheels for driving the vehicle along the ground; an extendable boom pivotally mounted to said body at or near its rear end for movement relative thereto between a 20 lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear wheels; lighting means operatively connected to said boom at or adjacent its end distal from said vehicle body; 25 electricity generation means including an internal combustion engine having an alternator or generator coupled thereto mounted to said vehicle body behind said extendable boom; electricity communication means connecting said electricity 30 generation means to said lighting means for transmitting electricity thereto for powering said lighting means; and electrical ballast in electrical communication with said lighting means and said electricity generation means, said JON05134 17 ballast being mounted to said vehicle body in a substantially closed chamber remote from said lighting means, said chamber having an air inlet and an air outlet and air supply means for causing air flow through said chamber from said air inlet to 5 said air outlet to cool said ballast.

11. Mobile lighting apparatus, including: a steerable vehicle having a vehicle body supported on a pair of spaced apart rear wheels and a pair of spaced apart 10 front wheels; drive means operatively connected to at least one of said pair of rear wheels and said pair of front wheels for driving the vehicle along the ground; an extendable boom pivotally mounted to said body at or 15 near its rear end for movement relative thereto between a lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear wheels; lighting means operatively connected to said boom at or 20 adjacent its end distal from said vehicle body; electricity generation means including an internal combustion engine having an alternator or generator coupled thereto mounted to said vehicle body substantially on one side of said extendable boom; 25 electricity communication means connecting said electricity generation means to said lighting means for transmitting electricity thereto for powering said lighting means; and electrical ballast in electrical communication with said lighting means and said electricity generation means, said 30 ballast being mounted to said vehicle body in a substantially closed chamber remote from said lighting means, said chamber having an air inlet and an air outlet and air supply means for cJONe 1]4 18 causing air flow through said chamber from said air inlet to said air outlet to cool said ballast.

12. Mobile lighting apparatus according to Claim 10 or Claim S 11, wherein said air supply means includes a blower arranged to suck air through a dust filter before entering the chamber via said air inlet.

13. Mobile lighting apparatus according to Claim 12, wherein 10 said blower is arranged. on the inlet side of said chamber downstream of the filter.

14. Mobile lighting apparatus according to any one Claims 10 Lo 13 including control means oporatively connected to said 15 electricity generation means and arranged to shut down said electricity generation means in response to the temperature of the air in said chamber reaching a predetermined level and/or air flow through said chamber falling to a predetermined level. 20

15. A method of converting a vehicle to lighting apparatus, the vehicle being a steerable vehicle having a body supported on a pair of spaced apart rear wheels and a pair of spaced apart front wheels and drive means operatively connected to at least 25 one of said pair of front wheels and said pair of rear wheels for driving the vehicle along the ground, an extendable boom pivotally mounted to said body at or near its rear end for movement relative thereto between a lowered position and a raised position with the longitudinal axis of tho boom 30 remaining generally in the same vertical plane relative to the rear wheels, and a counterweight mounted to said body to counter the weight of the boom, the method including: JO 5134 19 connecting lighting means to said boom at or adjacent its distal end; removing the counterweight at least in part and mounting electricity generation means to said body in a predetermined 5 position in place of the removed counterweight; and electrically connecting the electricity generation means to the lighting means.

16. A method according to claim 15 wherein said predetermined 10 position is selected such that the electricity gene-ration means acts as a suitable counterweight for the boom and the lighting means mounted thereon when fully extended,

17. A method of converting a vehicle to lighting apparatus, the 15 vehicle being a steerable vehicle having a vehicle body supported on a pair of spaced apart rear wheels and a pair of spaced apart front wheels and drive means operatively connected to at least one of said pair of front wheels and said pair of rear wheels for driving the vehicle along the 20 ground, an extendable boom pivotally mounted to said body at or towards the rear of the vehicle body for movement relative thereto between a lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear wheels, the method 25 including: mounting electricity generation means to said vehicle body in a predetermined position behind said boom, said electricity generation means including an alternator or generator driven by a second internal combustion engine; 30 connecting lighting neans to said boom at or adjacent its distal end; and electrically connecting said electricity generation means to said lighting means. cJON05 L 34 20

18. A method of converting a vehicle to lighting apparatus, the vehicle being a steerable vehicle having a vehicle body supported on a pair of spaced apart rear wheels and a pair of 5 spaced apart front wheels and drive means operatively connected to at least one of said pair of front wheels and said pair of rear wheels for driving the vehicle along the ground, an extendable boom pivotally mounted to said body at or towards the rear of the vehicle body for movement relative 10 thereto between a lowered position and a raised position with the longitudinal axis of the boom remaining generally in the same vertical plane relative to the rear wheels, the method including: locating said drive means on said vehicle body in a first 15 predetermined position substantially on one side of said boom and mounting electricity generation means to said vehicle body in a second predetermined position substantially on the opposite side of said boom, said electricity generation means including an alternator or generator driven by an internal 20 combustion engine; connecting lighting means to said boom at or adjacent its distal end; and electrically connecting said electricity generation means to said lighting means. 25

19. A method according to Claim 18, wherein said first and second predetermined positions are selected such that the electricity generation means and the drive means act as suitable counterweights for the boom and the lighting means 30 mounted thereon when fully extended and are arranged to laterally balance the vehicle. c.10NQ513 21

20. A method according to Claim 18 or Claim 19, wherein said first and second predetermined positions are selected such that said traction drive means and said electricity generation means substantially balance each other on opposite sides of S said boom.

21. A method according to any one of Claims 15 to 19, including mounting electrical ballast in a chamber in or on said vehicle body, said chamber having an air inlet and an air outlet, and 10 air supply means for causing air flow through said chamber from said air inlet to said air outlet to cool said ballast and connecting said ballast to said lighting means and said electricity generation means for electrical communication therewith. 15

22. Mobile lighting apparatus substantially as hereinbefore described with reference to the accompanying drawings.

23. Mobile lighting apparatus according to any one of Claims 1 20 to 14 substantially as hereinbefore described with reference to the accompanying drawings.

24. A method of converting a vehicle to mobile lighting apparatus substantially as hereinbefore described with 25 reference to the accompanying drawings.

25. A method of converting a vehicle to mobile lighting apparatus according to any one of Claims 15 to 21 substantially as hereinbefore described with reference to the 30 accompanying drawings. cJ0NO$ 154