Adair, Carl (12 Bendee Drive, Atwell Western Australia 6164, AU)
| 1. | A portable lighting tower comprising: a chassis mounted on a plurality of wheels for transporting the tower; a control console positioned on a side of the chassis; a power plant mounted on the chassis, the power plant controlled by the control console; a mast having a substantially vertical section mounted to an end of the chassis and an extendable section pivotally mounted to the vertical section; and, a light mounted to the extendable section, wherein the vertical section is rotatable about an axis parallel to its length by operation of a motor powered by the power plant under the control of the control console. |
| 2. | A portable lighting tower according to claim 1, wherein the control console is spaced from the vertical section. |
| 3. | A tower according to claim 1 or 2, further comprising a plurality of ground engaging stabilisers that are able to be lowered to engage the ground under the control of the control console. |
| 4. | A portable lighting tower comprising: a chassis mounted on a plurality of wheels for transporting the tower; a control console positioned on a side of the chassis; a power plant mounted on the chassis, the power plant controlled by the control console; a mast having a substantially vertical section mounted to an end of the chassis and an extendable section pivotally mounted to the vertical section; and, a light mounted to the extendable section, wherein a plurality of ground engaging stabilisers that are able to be lowered to engage the ground under the control of the control console, wherein the stabilisers extend to engage the ground such that the weight of the tower is at least in part distributed amongst the stabilisers when the tower is positioned for use. |
| 5. | A tower according to either claim 3 or 4, wherein the stabilisers are extendable such that the weight of the tower is distributed amongst the stabilizers and the wheels. |
| 6. | A tower according to any one of claims 3 to 5, wherein the stabilisers are extendable such that the weight of the tower is distributed amongst the stabilisers only. |
| 7. | A portable lighting tower according to any one of claims 3 to 6, wherein the stabilisers compensate when the extendable section is positioned with the light outside of the footprint of the chassis. |
| 8. | A portable lighting tower according to any one of claims 3 to 7, wherein the stabilisers compensate when the extended section is substantially horizontal. |
| 9. | A portable lighting tower according to claim 8, wherein the stabilisers compensate when the extended section is positioned for high wall overhang operation. |
| 10. | A portable lighting tower according to any one of claims 3 to 9, wherein the plurality of ground engaging stabilisers are coupled to the chassis and engage the ground to stabilise the chassis in operation, the pressure applied by each stabiliser to the ground is controllable such that the weight of the tower is distributed amongst the stabilisers. |
| 11. | A portable lighting tower according to claim 10, wherein the control of the stabilisers is automatically conducted under computer control in response to measurement of levelling of the trailer. |
| 12. | A portable lighting tower according to claim 11, wherein the computer control automatically adjusts the extension of each stabiliser according to positioning of the light relative to the chassis and/or according to undulation in the surface of the ground. |
| 13. | A portable lighting tower according to claim 11, wherein the computer control automatically extend the stabilisers to set and maintain the chassis to be level. |
| 14. | A portable lighting tower according to any one of the preceding claims, wherein the light is in the form of a lighting array pivotable in relation to the extendable section by a motor under the control of the control console. |
| 15. | A portable lighting tower according to any one of the preceding claims, further comprising a cabin mounted on the chassis, the cabin being arranged to be structurally load bearing. |
| 16. | A portable lighting tower according to claim 15, wherein the cabin supports the extended section and lighting array when the extendable section is horizontal in a transportable mode. |
| 17. | A portable lighting tower according to any one of the preceding claims, wherein the base of the cabin is arranged to be liquid retentive so that liquid spills within the cabin are retained within the liquid retention area. |
| 18. | A portable lighting tower according to any one of the preceding claims, wherein the cabin is modularised such that the power plant may be positioned within a power plant module such that it has unhindered access. |
| 19. | A portable lighting tower according to any one of the preceding claims, wherein the control console is positioned within a control console module of the cabin. |
| 20. | A portable lighting tower according to any one of the preceding claims, wherein the control console can be accessed or removed from the cabin in an unrestricted manner. |
| 21. | A portable lighting tower according to any one of the preceding claims, wherein the control console is positioned on a side panel of the cabin. |
Field of the Invention
The present invention relates to lighting towers that are transportable.
Background of the Invention
Existing portable lighting towers include those in the form of a vehicle towed trailer with an extendable mast that is pivotable so that a section of the mast holding a lighting array can be horizontally positioned on the trailer for transport and vertically positioned and extended for use.
Before extension ' the angle of the lighting array in relation to the pivotable section of the mast can be adjusted and then fixed in place. The mast is then pivoted to the vertical position. A lever attached to a bottom section of the mast is able to turn the mast so that the lighting array points in the desired direction. The mast is fixed in its rotated position by placing a pin through a hole of a locking mechanism. The locking mechanism is in the form of a semicircular plate having a number of holes arranged in an arc into which a pin can be inserted. Another plate has a single hole. One of the plates rotates with the mast and the other is fixed to the trailer. When one of the holes of the first plate aligns with the hole in the other plate such that the mast and lighting array are at the desired angle the pin is inserted in the aligned holes so as to fix the mast in its position in relation to the rest of the trailer.
Problems arise when wind blows on the lighting array which acts as a sail. The wind pressure can apply a torque to the mast which can make removal of the pin difficult. In
addition, once the pin is removed a gust of wind can overpower the person on the lever and can result in the person being crushed by the lever against a front wall of the trailer.
It is also known for the trailer to have a manually lowerable stabiliser in each of its four corners. The stabilisers are lowered to make contact with the ground so as to stabilise the tower unit against gusts of wind. The process of lowering each of the stabilisers is time consuming because the person must go to each of the four corners lower the respective stabiliser and lock it in position.
Existing portable tower units are not capable of being operated in a high wall overhang mode, which is where the tower unit is positioned above a wall that descends from the ground on which the tower is positioned, such as at the edge of a pit of a mine excavation site. The mast of the tower in this operation needs to extend horizontally not vertically over the edge of the wall so as to project light from the lighting array back onto the wall. If this were attempted with existing portable tower units the unit would over balance and topple over.
Summary of the Invention
According to the present invention there is provided a portable lighting tower comprising: a chassis mounted on a plurality of wheels for transporting the tower; a control console positioned on a side of the chassis; a power plant mounted on the chassis, the power plant controlled by the control console;
a mast having a substantially vertical section mounted to an end of the chassis and an extendable section pivotally mounted to the vertical section; a light mounted to the extendable section; wherein the vertical section is rotatable about an axis parallel to its length by operation of a motor powered by the power plant under the control of the control console.
Preferably the control console is spaced from the vertical section.
Preferably the tower further comprises a plurality of ground engaging stabilisers that are able to be lowered to engage the ground under the control of the control console.
According to another aspect of the present invention there is provided a portable lighting tower comprising: a chassis mounted on a plurality of wheels for transporting the tower; a control console positioned on a side of the chassis; a power plant mounted on the chassis, the power plant controlled by the control console; a mast having a substantially vertical section mounted to an end of the chassis and an extendable section pivotally mounted to the vertical section; a light mounted to the extendable section; wherein a plurality of ground engaging stabilisers that are able to be lowered to engage the ground under the control of the control console, wherein the stabilisers extend to engage the ground such that the weight of the tower is at least in part distributed amongst the stabilisers when the tower is positioned for use.
In one embodiment the stabilisers are extendable such that the weight of the tower is distributed amongst the stabilisers and the wheels. In another embodiment the stabilisers are extendable such that the weight of the tower is distributed amongst the stabilisers only.
Preferably the stabilisers compensate when the extendable section is positioned with the light outside of the footprint of the chassis.
Preferably the stabilisers compensate when the extended section is substantially horizontal. Preferably the stabilisers compensate when the extended section is positioned for high wall overhang operation.
Preferably the plurality of ground engaging stabilisers are coupled to the chassis and engage the ground to stabilise the chassis in operation, the pressure applied by each stabiliser to the ground is controllable such that the weight of the tower is distributed amongst the stabilisers. Preferably, the control of the stabilisers is automatically conducted under computer control in response to measurement of levelling of the trailer. The computer control automatically adjusts the extension of each stabiliser according to positioning of the light relative to the chassis and/or according to undulation in the surface of the ground. The automatic extension of the stabilisers sets and maintains the chassis to be level.
Preferably the light is in the form of a lighting array pivotable in relation to the extendable section by a motor under the control of the control console. Typically the lighting array is rotatable about a longitudinal centroid axis of the extendable section by activation of a first motor under the control of the control console.
Typically the lighting array is pivotable in a vertical plane in relation to the extendable section by activation of a second motor under the control of the control console.
Preferably the tower comprises a cabin mounted on the chassis, the cabin being arranged to be structurally load bearing. Preferably the cabin supports the extended section and lighting array when the extendable section is horizontal in a transportable mode. Preferably the base of the cabin is arranged to be liquid retentive so that liquid spills within the cabin are retained within the liquid retention area. Preferably the cabin is modularised such that the power plant may be positioned within a power plant module such that it has unhindered access. Preferably the control console is positioned within a control console module of the cabin. Preferably the control console can be accessed or removed from the cabin in an unrestricted manner. Preferably the control console is positioned on a side panel of the cabin.
Brief Description of the Drawings
In order to provide a better understanding, preferred embodiments of the present invention will now be described in greater detail, by way of example only, with reference to the accompanying drawings, in which:
Figure 1 is an upper perspective view of a portable lighting tower according to a first embodiment of the present invention;
Figure 2 is an upper perspective from the rear of the portable lighting tower of Figure 1;
Figure 3 is a side elevation of the portable lighting tower of Figure 1; Figure 4 is a front perspective view of the portable lighting tower of Figure 1 ready for use in the standard configuration;
Figure 5 is the portable lighting of Figure 1 ready for use in a high wall configuration;
Figure 6 is a side elevation of a portable lighting tower according to ■ a second embodiment of the present invention;
Figure 7 is an upper perspective view of the lighting tower of Figure 6;
Figure 8 is an upper perspective view of the lighting tower of Figure 6, ready for use in a high wall configuration; and,
Figure 9 is a front elevation of the lighting tower of Figure 6.
Detailed Description of the Preferred Embodiments
Referring to Figures 1 to 5, there is shown a portable lighting tower 100 which comprises a structural chassis 102 mounted on ground engaging wheels 106. A cabin 104 is integrally mounted on the chassis 102 (such as for example by welding) . The cabin 104 is structured so as to be load bearing. A draw bar 108 extends from the front of the tower 100 so that it may be towed to a location for operation.
Pivotally mounted to a front end of the cabin 104/chassis 102 is a vertical mast section 110. As best seen in Figure 3 the mast section 110 is coupled by a pivotal coupling 111 and a motor 112. The motor 112 is fixed to the front of the cabin 104 so that upon rotation of a rotor extending from the motor mast section 110 is caused to pivot.
Pivotally coupled to the top of the mast section 110 is an extendable mast section 114. The mast section 114 is coupled to the mast section 110 by a pivotal joint 115. The pivotal joint 115 allows the extendable mast section 114 to pivot in a vertical plane relative to the mast
section 110. Hydraulic ram 117 is able to drive the mast section 114 so as to raise it to be substantially vertical. When in the vertical orientation the hydraulic pressure maintains the vertical position of the extendable mast section 114. A travel stop 119 is provided part way along the length " of the mast section 110 so that the mast section 114 is stopped from pivoting any further when the end of the mast section 114 closest to the pivotal joint 115 contacts the travel stop 119. Preferably this coincides with the end of travel of the hydraulic piston in hydraulic ram 117. The hydraulic ram 117 may also lower the extendable mast section 114 so that the mast section 114 rests on cradle 118. Cradle 118 is mounted to the top of the cabin 104 at the rear end of the cabin.
The extendable mast section 114 is preferably telescopically extendable to give extra height to the light or provide extra distance between the light and the chassis in high wall overhang operation. Limit switches may be used to sense the amount of extension of the extendable mast section 114 so that if the mast section 114 is not oriented to be vertical, such as in a high wall overhang operation, the amount of extension can be limited so as to prevent toppling of the tower 100.
A flexible conduit guard 125 for carrying electrical wiring/hydraulic lines is attached to a rigid conduit guard 126. The flexible conduit guard 125 guards against damage to the conduits and moves as the mast section 114 extends or retracts.
At an end of the section 114 a lighting array 116 is pivotally coupled to the section so as to alter the angle of the lighting array 116 with respect to the mast. A motor coupled between the array and the end of the mast section 114 can pivot the lighting array through a range of movement relative to the mast so that the inclination
angle of the lighting can be adjusted. In addition the lighting array can be rotated so that the lighting array can pan.
At the bottom in substantially 1 each of the four corners of the cabin 104 is a stabiliser 120. The stabilisers 120 are extendable downwardly to engage the ground as seen in Figures 4 and 5. The stabilisers 120 may be capable of lifting the tower 100 from the ground so that the wheels 106 disengage from the ground when the stabilisers 120 are fully extended. This ensures that the weight of the tower 100 is evenly distributed and the trailer is firmly planted on the ground. Alternatively the stabilisers 120 may be lowered without lifting the wheels 106 from the ground so that the wheels 106 bear some of the weight of the tower 100.
After the lighting tower 100 is positioned in its intended ' location for operation, its hydraulic / electrical / electronic systems are primed. Then actuation of a single switch of a control console activates extension of the stabilisers, levelling and level monitoring.
The stabilisers will continue to extend until a predetermined pressure is achieved. Upon contact of the stabiliser feet with the ground a signal is sent to a CPU/PLC (processor) of the control console. The hydraulic cylinder pressure is monitored and when a first particular cylinder pressure is detected, this is interpreted as contact of a stabiliser with the ground. Thereafter the stabilisers will extend until a second preset pressure is achieved, such that the tower weight is shared equivalently by the wheels 106 and stabilising feet 120.
An optical sensor for self levelling system will ensure the quantity of hydraulic fluid entering or leaving the cylinder for each stabiliser is adjusted until no further
adjustment is necessary.
Deactivation of this system retracts the stabilisers prior to termination of tower usage whilst maintaining the tower 100 in a horizontal orientation.
The levelling system is to be designed such that the deactivation may only be effected when the mast section 114 is fully retracted and nested in the mast cradle 118.
The automated levelling system operates on the basis of an array of signals received from stabiliser leg pressure sensors and level sensors. Interpretation of these signals by the processor causes instruction to be provided to the hydraulic motor to turn on and off, coincident with the opening and closing of bidirectional valves in series with the double acting cylinders. The design concept accommodates all mast angles and extensions, effects of wind loading and ground surface conditions.
On each side of the cabin 104 are cabin bay doors 124. In Figure 1 the cabin doors 124 are open; in Figure 2 they are closed. Within the cabin is a power plant, usually in the form of a diesel motor. The diesel motor is not shown for clarity. Also inside the cabin is the control console with instrumentation and controls for monitoring and controlling the power plant, the motors, the hydraulic ram 117 and hydraulic extension of the stabilisers 120. The control console is positioned to be spaced from the mast section 110 so that the operator is clear of a crushing zone at the front of the tower 100. The power plant can power the lighting array 116 by powering a generator. The power plant also powers a hydraulic pump to operate the motors, hydraulic ram and stabiliser hydraulics.
The base of the cabin 104 is sealed against fluids passing therethrough so that if there is any spill of oil, diesel
or some other liquid from the power plant or any liquid within the cabin 104 it will be contained in a sump section of the cabin 104.
Figure 4 shows the operation of the lighting tower. Extension section 122 of mast section 114 extends from the mast section 114. Mast section 114 is seen pivoted into a vertical position. The mast section 110 can also be seen pivoted 90° clockwise about the motor 112 so that the lighting array is pointing to the left hand side of the tower 100.
In Figure 5 the tower 100 is arranged for a high wall overhang configuration. In this configuration the extension section 122 extends from the mast section 114 off from the one side (the left-hand side) of the tower (it could equally be the right-hand side) . • The sections 114 and 122 are substantially horizontal and the lighting array 116 has been pivoted by approximately 90°. This allows the lighting array to overhang a high wall such as the edge of a mine site wall. The lighting array can then project light on to the mining face or into a pit such as for example a mine pit. As previously mentioned the extension section 122 may not fully extend from mast section 114 in this mode.
Figures 6 and 7 show a portable lighting tower 100' according to a second embodiment. The tower 100' comprises a space frame chassis (not shown) to which a cabin 104' is attached. In this embodiment the cabin is load bearing. A drawbar 108' connected to the chassis extends forward of the tower 100'. Wheels 106' are each attached to a bogey (not shown) , which is in turn connected to members of the chassis. Accordingly, the tower 100' can be towed by a vehicle to a selected location for operation.
A vertically mounted mast section 110' is connected in a pivoting arrangement to a front end of the chassis by a pivotable coupling 111' and a rotary actuator, such as motor 112' . The motor 112' is fixed to the chassis, such that rotation of a rotor of the motor 112' causes the mast section 110' to pivot.
A mast section 114' is attached by a pivot joint 115' to the uppermost end of the mast section 110'. A hydraulic ram 117' can be driven to change the relative orientation of the mast section 114' with respect to the mast section 110' by pivoting the mast section 114' about the pivot joint 115'. The hydraulic ram 117' is able to raise the mast section 114' to be substantially parallel to mast section 110'. The mast section 114' can be stopped from pivoting beyond vertical using a stop 119'. The hydraulic ram 117' is also able to lower the outer telescoping section 114' into a resting position in a cradle 118'. The cradle 118' is mounted at the top of the cabin 104' towards the rear end of the cabin 104'.
As shown in Figures 8 and 9, the outer telescoping section 114 ' further comprises an inner telescoping section 122 ' . A lighting array 116' is attached by a pivotable coupling arrangement 130' to the end of the inner telescoping section 122', which extends from within the outer telescoping section 114 ' . The pivotable coupling arrangement 130' allows the direction (right and left pan) and inclination angle of the lighting array 116' to be adjusted with respect to the outer telescoping section 114'. In this embodiment, the pivotable coupling arrangement 130' comprises a rotary actuator and hydraulic ram. Accordingly, the direction of lighting can be adjusted by driving the motor and the inclination angle of the lighting can be adjusted by hydraulic ram of the pivotable coupling arrangement 130', thus altering the relative orientation of the lighting array 116' .
Due to the need for conduits to carry electrical wiring to the lighting array 116' and hydraulic lines to the pivotable coupling arrangement 130', a flexible conduit guard 125' and a rigid conduit guard 126' allow the conduits to be guarded, as well as moved, as the telescoping section 122' extends or retracts from the section 114' . The rigid conduit guard 126' is attached to the inner telescoping section 122' and the flexible conduit guard 125' is attached to the outer telescopic section 114' .
The flexible conduit guard 125' is attached to the end of the rigid conduit guard 126' that is remote from the lighting array 116' .
A stabiliser 120' is provided at each of the four corners of the cabin 104' . Each stabiliser 120' is at an angle to the horizon and is arranged to extend both downwardly and outwardly of the cabin 104' to engage the ground. The control of the stabilisers 120' is similar to that described in the previous embodiment.
Each side of the cabin 104' is provided with one or more cabin bay doors 124 ' . In Figure 6 the cabin doors 124 ' are closed, and in Figure 7 they are open. As shown in
Figure 7, within the cabin 104' is a power plant, which is in the form of a diesel motor 132'. The diesel motor 132' is connected to an electrical generator (not shown) . The motor may also be connected to a hydraulic pump (also not shown) , however it is preferred that the hydraulic pump be powered by the generator. It will be appreciated that any suitable power source could be used in place of the diesel motor 132' .
A control console 140' is also provided in the cabin 104'. The control console 130' provides an operation interface
with instrumentation and controls for controlling the power plant, the motors, the extension of both the hydraulic ram 117' and each of the stabilisers 120'. The positioning of the control console 130' is such that the operator is clear of a crushing zone formed at the front of the tower 100' by the mast.
The base of the cabin 104' is provided with a bunded area (not shown) , or a "sump section", at the base of the cabin 104', for the containment of any spilled fluids from the power plant or any other liquid within the cabin 104'.
Figures 8 and 9 show the tower 100' oriented in a high wall configuration. In this configuration, the inner telescoping section 122' has not been fully extended from the outer telescoping section 114'. The outer telescoping section 114' and inner telescoping section 122' are substantially horizontal. The lighting array 116' has been pivoted to direct light generally downward.
As best shown in Figure 9, the stabilisers 120' have been fully extended. Accordingly, the wheels 106' of the tower 100' have been lifted off the ground G. The foot of each stabiliser 120' is able to be moved outwardly and downwardly of the cabin 104'. When all four stabilisers are fully extended, the separation of the feet of both the front pair of stabilisers 120' and the rear pair of stabilisers 120' is wider than the wheel track of the tower 100', as shown in Figure 9.
It will be understood to persons skilled in the art of the invention that many modifications may be made without departing from the spirit and scope of the invention.
In the claims of this application and in the description of the invention, except where the context requires otherwise due to express language or necessary
implication, the words "comprise" or variations such as "comprises" or "comprising" are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.