[0001] Method for installing piles

FIELD OF THE INVENTION

[0002] The present invention relates to a method for installing a plurality of piles into the ground.

[0003] BACKGROUND TO THE INVENTION

[0004] A number of construction projects require the insertion and placement of a large number of screw piles or blade piles into the ground. For example, when constructing a photovoltaic solar farm, the solar cells are typically supported on a solar tracker that rotates so that the solar cells follow the sun as it moves across the sky during the day. The solar tracker will typically comprise a motor having a torque tube extending therefrom, with the solar cells being mounted directly or indirectly to the torque tube. The torque tube has to be located above ground level and typically beams or piles are driven into the ground to achieve this outcome. In some solar farms, each solar cell array is mounted on a row of single piles. In other solar farms, each solar cell array is supported on two parallel rows of spaced piles, with each pile in one row forming a pair with a pile in the adjacent row. Each pair of piles will typically hold a torque tube mount via an intermediate structure supported on the pair of piles.

[0005] Installation of a large number of piles can involve significant materials handling and labour inputs. For example, current solar farm pile installation methods typically involve the following steps:

1) receive the piles in packs from the manufacturer of the piles. These are typically received on the back of trucks and require unloading onto hardstands in a holding yard.

2) sort the piles into colour-coded groups, relative to each tracker location and pile/load design. In this regard, in solar farms, the solar cells mounted at the edges of the solar farm typically require support by stronger piles, due to greater exposure to wind loading at the edges of the solar farm. As a corollary, piles located to the interior of the solar farm are somewhat sheltered from wind by the solar cells mounted outside them, and therefore smaller piles may be used. 3) once sorted into groups, the pile packs must then be transported out over the entire solar farm site. It will be understood that solar farm sites can be very large, of the order of hundreds of acres, and this requires significant transport costs.

5) the packs of piles are broken down and the piles must then be transported to the individual solar tracker locations.

6) the piles are then moved to the final installed locations for pickup and installation.

[0006] Current installation methods for piles on solar farms require a large number of individuals to manage pile placement and the pile installation process. For example, acquisition and quality control staff are required in the holding yard, to sort and group pile packs for bulk distribution out and onto the site. Individuals are required to transport the piles out onto site, break up the pile packs, group the piles into tracker areas and then pile locations. During installation, each and every pile is picked up by hand and fed into a machine that installs the piles.

[0007] Current installation methods for piles on solar farms results in a number of personnel being exposed to the elements over the entire site during pile placement and installation. This can introduce occupational health and safety issues, particularly where the solar farm is being installed in either a hot region or a cold region, with issues of heatstroke occurring during solar farm installation in hot areas and issues of frostbite being noted in installation of solar farms in cold areas. Further, operators are exposed to possible snakebite and exposure to other potentially dangerous wildlife. As there is a number of individuals located on the ground, those individuals are also exposed to risk of injury or death during the handling and installation of a large number of piles.

[0008] There remains a need to provide improved methods for installing a large number of piles which will desirably reduce Occupational Health & Safety risks to workers and result in a more efficient and cost-effective installation of the piles.

BRIEF DESCRIPTION OF THE INVENTON

[0009] In a first aspect, the present invention provides a method for installing a plurality of piles into the ground, the method comprising a) loading a cradle with a plurality of piles, the piles being positioned generally horizontally on the cradle, b) orienting a projection associated with a pile installation apparatus in a horizontal direction, c) inserting the projection into a shaft of a pile, d) moving the projection to remove the pile from the cradle, e) installing the pile into the ground in a desired location, f) withdrawing the projection from the pile once the pile has been installed, and g) repeating steps (b) to (f).

[0010] In one embodiment, the cradle supports each pile individually. In this manner, withdrawing one pile from the cradle will not affect the positioning or location of the other piles on the cradle.

[0011] In one embodiment, the method of the present invention comprises loading the cradle with piles at a first location and moving the cradle to an installation location.

[0012] In one embodiment, step (g) may be modified so that step (g) comprises repeating steps (a) to (f), step (a) being repeated when the cradle has been emptied of piles.

[0013] In one embodiment, the cradle may comprise a cartridge. In one embodiment, the cradle comprises a plurality of cartridges.

[0014] In one embodiment, the method of the present invention comprises loading a first cradle with piles at a first location and moving the first cradle to an installation location, loading a second cradle with piles and moving the second cradle to the installation location, and when the first cradle has no piles remaining thereon, moving the first cradle to the first location to reload the first cradle with piles and removing piles from the second cradle for installation into the ground at the installation location. In this embodiment, the first cradle can be loaded at, for example, a holding yard and moved or transported to the installation site where steps (a) to (g) are conducted. Whilst that is occurring, the second cradle can be loaded with piles at the holding yard and then be transported to the installation site. The second cradle can then be held in wait until the supply of piles on the first cradle is exhausted. The first cradle can then be moved away from installation site back to the holding yard and the second cradle then used to provide piles for installation at the installation site. If the solar farm is being installed on a very large site that requires lengthy transit times, more than two cradles may be used to supply piles for each installation site.

[0015] In one embodiment, the cradle comprises a wheeled cradle. In another embodiment, the cradle comprises a cradle mounted on a trailer or sitting on a trailer. In another embodiment, the cradle comprises a cradle mounted on a flat bed vehicle or sitting on a flat bed vehicle. In one embodiment, the cradle is removable from the vehicle, or the cradle is removable from the trailer, or the trailer is removable from the flat bed vehicle.

[0016] In one embodiment, the cradle comprises a plurality of pile supports, each pile support supporting an individual pile when the cradle is filled with piles.

[0017] In one embodiment, the cradle supports a plurality of piles in a first row of cradles and the cradle supports a plurality of piles in a second row of piles, the first row of piles being located above the second row of piles.

[0018] In one embodiment, the piles are installed as a single row of piles.

[0019] In one embodiment, the piles are installed in two parallel rows, with adjacent piles in each row forming a pair of piles.

[0020] In one embodiments, the piles are installed as pairs, with one pile in a pair being angled relative to the other pile in the pair.

[0021] In a second aspect, the present invention provides a method for installing a plurality of sets of two spaced piles into the ground, the method comprising a) loading a cradle with a plurality of piles, the cradle arranging the piles into a first row of piles and a second row of piles, the first row of piles being located above the second row of piles, the piles being positioned generally horizontally in the cradle, b) orienting a first projection associated with a first pile drive in a horizontal direction and orienting a second projection associated with a second pile drive in a horizontal direction, c) inserting the first projection into a shaft of a pile in the first row of piles, inserting the second projection into a shaft of a pile in the second row of piles, d) moving the first projection and the second projection to remove the first pile from the first row of piles and remove the second pile from the second row of piles, e) screwing the piles into the ground, f) withdrawing the first projection from the first pile and withdrawing the second projection from the second pile, and g) repeating steps (a) to (f), or repeating steps (b) to (f).

[0022] In one embodiment of the second aspect of the present invention, the first projection is spaced by a distance from the second projection, and the first row of piles and the second row of piles on the cradle are vertically spaced by the same distance.

[0023] In one embodiment of the method of the second aspect of the present invention, the piles are loaded into two rows on the cradle, with each pile in the first row being located vertically above a pile in the second row such that a pile in the first row forms a pair with a pile in the second located vertically below, the first row being spaced from the second row by a distance that corresponds to a required spacing for installation of the piles of a pair into the ground.

[0024] In a third aspect, the present invention provides a method for installing a plurality of piles into the ground, the method comprising a) at a holding yard or loading yard, loading a first cradle with a plurality of piles, the piles being positioned generally horizontally on the first cradle, and moving the first cradle now filled with piles to an installation site, b) orienting a projection associated with a pile installation apparatus in a horizontal direction, c) inserting the projection into a shaft of a pile, d) moving the projection to remove the pile from the cradle, e) installing the pile into the ground in a desired location, f) withdrawing the projection from the pile once the pile has been installed, g) repeating steps (b) to (f), h) at a holding yard or loading yard, loading a second cradle with a plurality of piles, the piles being positioned generally horizontally on the second cradle, and moving the second cradle now filled with piles to an installation site, i) when the first cradle has been emptied of piles, moving the first cradle from the installation site to the holding yard or loading yard, and j) repeating steps (b) to (f), utilising piles from the second cradle.

[0025] It will be understood that, in the third aspect of the present invention, a third cradle may also be used.

[0026] In embodiments of the present invention, once the cradle that is being used to supply piles to the installation apparatus has been emptied of piles, it returns to the holding out of storage yard to be re-loaded with piles and another loaded cradle at the installation site is then used to supply piles to the installation apparatus.

[0027] In one embodiment, the piles are delivered to or located at a storage location or delivery location and a first cradle is loaded with piles and the first cradle is then moved to an installation location, and a second cradle is loaded with piles at the storage location or delivery location and moved to the installation location, and when the piles on the first cradle have been installed, the first cradle is returned to the delivery location or storage location and re-filled with piles whilst the piles on the second cradle are moved to or are present at the installation location and the piles on the second cradle are installed. [0028] In one embodiment, the delivery location or storage location comprises a delivery or storage yard, or a delivery or storage shed, or a delivery or storage warehouse.

[0029] In one embodiment, the installation apparatus used to install the piles into the ground comprises a first projection. The first projection can be oriented between a horizontal orientation and an installation orientation. The installation orientation may be generally vertical or it may be at an angle to vertical. The first projection may comprise a driveshaft for driving the pile into the ground. The driveshaft may be associated with a mast along which the driveshaft can reciprocally move.

[0030] In another embodiment, the installation apparatus used to install the piles into the ground comprises a first projection and a second projection. The first projection and the second projection can be oriented between a horizontal orientation and an installation orientation. The first projection may comprise a driveshaft for driving a pile into the ground. The second projection may comprise a driveshaft for driving a pile into the ground. The piles may be installed so that, in the installed position, they are parallel to each other, or in the installed position they are at an angle to each other.

[0031] In one embodiment, the installation apparatus used installs the first pile and the second pile generally parallel to each other and the first pile in the second pile are installed into the ground simultaneously.

[0032] In another embodiment, the first pile and the second pile are installed at an angle to each other and the first pile is installed into the ground and the second pile is subsequently installed into the ground.

[0033] In one embodiment, an operator of the installation apparatus installs the piles without having to leave a cabin of the installation apparatus. In one embodiment, a driver moving the cradles remains in the cabin of the vehicle carrying or towing the cradles whilst the piles are being installed. In this manner, there are no on-ground personnel required during the installation of the piles, with all personnel at the installation site being located within the cabins of their respective vehicles during the installation process, during normal installation (it being appreciated that personnel may be required to leave their cabins during abnormal operating conditions, for example, in the event of equipment breakdowns or malfunctioning). As all personnel remain within the vehicles during normal installation operations, the personnel will be much more comfortable, being shielded from the sun and any extreme temperatures. Further, as personnel have been removed from the ground in the vicinity of the installation site, Occupational Health & Safety significantly increased. It is noted that there have been severe injuries and deaths at the site of pile installation during solar farm construction in the past.

[0034] In one embodiment, once a pile or a pair of piles has been installed at a first location, the cradle is moved to a next installation site and the installation apparatus is moved to a next installation site. For example, if two rows of piles are being installed, a first pair of piles may be installed and then the cradle and the installation apparatus moved to the location where the next pair of piles need to be installed. The location of the cradle and the location of installation apparatus may be controlled by GPS positioning and/or laser positioning to ensure accurate location. Alternatively, the operators of the vehicle is moving the cradle and the installation apparatus may be provided with a display showing location data, such as GPS data and/or laser positioning, to enable accurate positioning of the cradle and the installation apparatus by the operator of the vehicles.

[0035] In one embodiment, step (d) comprises rotating the projection and the pile upwardly to cause the pile to be lifted off the cradle and optionally slide downwardly along the projection, and subsequently operating a gripper to hold the pile in position relative to the projection.

[0036] In one embodiment, step (d) comprises moving the projection vertically to lift the pile vertically, moving the projection laterally away from the cradle to move the pile away from the cradle and rotating the projection and the pile upwardly to cause the pile to be lifted off the cradle and optionally slide downwardly along the projection, and subsequently operating a gripper to hold the pile in position relative to the projection.

[0037] In one embodiment, step (e) comprises rotating the pile to a vertical orientation and inserting the pile into the ground.

[0038] In one embodiment, step (e) comprises rotating the pile to a desired installation angle and inserting the pile into the ground. [0039] The present invention provides a method for installing a plurality of piles that provides for efficient materials handling and enhanced operator safety. The method of the present invention allows for the use of one or a small number of holding yards for storage of piles. The piles can be loaded onto appropriate cradles and the cradles can then be moved to the desired installation sites. At the installation site, piles from the first cradle are installed into the ground. At the same time, an emptied second cradle (and possibly one or more additional further cradles) can be undergoing the process of moving back to the holding yard, being loaded with piles and moving back to the installation site. Once the piles on the first cradle have been installed, the first cradle moves back to the holding yard and the re-loaded second cradle can be positioned so that piles can be removed from the second cradle for installation into the ground.

[0040] Further, the method of the present invention allows for the operators of the cradles and installation machinery to remain in the vehicle cabins at the installation site. Therefore, the operators can stay out of the sun in air-conditioned comfort whilst also being removed from potential physical danger that can be found on the ground in the vicinity of the installation site.

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:

[0042] Figure 1 shows a schematic flowsheet showing the steps of an embodiment of a method of the present invention;

[0043] Figures 2 to 7 show schematic views of the steps involved in removing pairs of piles from a cradle and installing them vertically into the ground, in accordance with an embodiment of the present invention; and

[0044] Figures 8 to 11 show schematic views of the steps involved in installing a pair of piles into the ground, with the piles being at an angle to each other. DETAILED DESCRIPTION OF THE INVENTION

[0045] The skilled person will understand that the drawings have been provided for the purposes of describing preferred embodiments of the present invention. Therefore, it will be understood that the present invention should not be considered to be limited to the features as shown in the attached drawings.

[0046] Figure 1 shows a schematic diagram outlining the various steps of the present invention. In step 1, a pile installation apparatus 10 that is capable of installing 2 piles at once, is located at an installation site. For example, the pile installation apparatus 10 may be located at a region of a solar farm that is being constructed where two rows of piles need to be installed in order to support a solar tracker/solar array. A vehicle 12 carrying or towing a cradle 15 that is holding a plurality of piles 11 is located next to the pile installation apparatus 10. The cradle on the vehicle 12 has been filled with piles at a holding yard (not shown) and then the vehicle 12 travels from the holding yard to the installation site. The vehicle 12 is replacing another vehicle 14 that has had all the piles on its cradle installed into the ground, so that its cradle is empty. Whilst the pile installation apparatus 10 installs the piles from the vehicle 12, vehicle 14 travels back to the holding yard (step 2). At the holding yard the cradle 15 of the vehicle 14 is off loaded by forklift 16 for refilling with piles (step 3). The quality assurance and acquisition teams sort and select the correct colour coded pile types for the next solar tracker installation locations and the cradle 15 is re-loaded with the correct piles (step 4). The forklift 16 then reloads the filled cradle 15 onto the vehicle 12 (step 5). It will be appreciated that the vehicle 14 may be towing a trailer and the cradle 15 may be placed onto the trailer of the vehicle 14. The vehicle 14 with the filled cradle 15 then drives back to the installation site where it waits for the cradle of the vehicle 12 to be emptied of piles. Vehicle 12 then drives off to return to the holding yard so that its cradle can be filled with piles and vehicle 14 moves into the desired position to enable the piles on cradle 15 to be removed by the pile installation apparatus 10 and installed into the ground.

[0047] Figures 2 to 7 show schematic diagrams of the piling installation apparatus 10 installing a pair of piles into the ground in a vertical orientation. The piling installation apparatus 10 comprises an excavator 20 having a boom arm 21. A twin mast pile installation apparatus 22 is fitted to the end of the boom arm. The twin mast pile installation apparatus 22 includes a first projection, in the form of a first driveshaft 23 and a second projection, in the form of a second driveshaft 24. Drive motors 25, 26 are used to turn driveshaft 23, 24, respectively. The drive motors 25, 26 may also enable hammer percussion to be applied to the driveshafts if the piles encounter hard ground during installation. The driveshafts 23, 24 can be extended and retracted relative to a base frame 27. The base frame 27 can also be rotated about a horizontal axis, as described hereunder.

[0048] Figure 2 shows the cradle 15 carrying first piles 11A and second piles 1 IB. The first piles 11 A are located at a fixed height above the second piles 1 IB by the construction and arrangement of the cradle 15. The vertical height between piles 11 A and 1 IB is essentially identical to the space between the driveshafts 23, 24 when they are in the position shown in figure 2. The cradle 15 is positioned on a trailer 28 that is towed by vehicle 12. The cradle 15 has a lower frame 29 for supporting the piles 1 IB, an upper frame 30 for supporting the piles 11 A and a plurality of uprights 31 for holding the upper frame 30 in position above the lower frame 29. The cradle may be made from steel and welded together. The lower frame 29 carries one or more plates having a plurality of spaced recesses thereon, each individual recess receiving a pile. From the side, the one or more plates may look similar to a wine rack. Persons skilled in the art will appreciate that there will be a number of different arrangements in which each individual pile may be separately supported by the cradle. Each individual pile 11 A is located vertically above an associated individual pile 1 IB.

[0049] In order to remove the piles 11A and 1 IB from the cradle 15, the twin mast pile installation apparatus 22 is oriented so that the driveshafts 23, 24 are essentially horizontal or essentially parallel to the shafts of piles 11 A and 1 IB. The driveshaft 23 is aligned with the opening in the top of the shaft of one pile 11 A and the driveshaft 24 is aligned with the opening in the top of the shaft of one pile 1 IB that is directly below the individual pile 11 A. This is the orientation as shown in figure 2.

[0050] The twin mast pile installation apparatus is then operated so that the driveshafts 23, 24 are operated to extend into the shafts of the piles 11 A, 1 IB. This is shown in figure 3. The twin mast pile installation apparatus 22 is then raised vertically by a small distance to lift the piles 11 A, 1 IB off the cradle and the driveshafts 23, 24 are then retracted horizontally and towards the excavator 20. This, of course, moves the piles 11 A, 1 IB horizontally with the driveshafts, as the piles 11 A, 1 IB are now supported by the driveshafts. Alternatively, using a manual loading operation, a “kick-out” configuration temporarily positions the driveshafts 23, 24 askew from the vertical, and the piles 11 A, 11 are manually slid onto the driveshafts 23, 24.

[0051] Once the ends of the piles 11 A, 1 IB are clear of the cradle 15, the twin mast pile installation apparatus is rotated upwardly, as shown in figure 4. If the piles 11 A and 1 IB have not fully seated on the driveshafts 23, 24, the piles 11 A, 1 IB will slide down the driveshafts until they are fully seated. Grippers (not shown) on the twin mast pile installation apparatus 22 then grip the piles 11 A, 1 IB and hold the piles in position relative to the driveshafts 23, 24. The boom arm 21 of the excavator 20 is then moved and the installation apparatus 22 is rotated until the piles 11 A, 1 IB are located vertically above the desired installation location for those piles. This is shown in figure 5. The drive motors 25, 26 are then operated to drive the piles 11 A, 1 IB into the ground as shown in figure 6. As the piles 11 A, 1 IB are driven into the ground, the drive motors 25, 26 move downwardly, as shown in figure 6. In the installation operation shown in figure 6, the drive motors 25, 26 may be operated simultaneously to simultaneously drive the piles 11 A, 1 IB into the ground.

[0052] Once the piles 11 A, 1 IB have been properly inserted into the ground, the driveshafts 23, 24 are moved upwardly, as shown in figure 7, to remove the drive shafts from the shafts of the installed piles 11 A, 1 IB. The excavator 20 then moves along the to the next location at which the next pair of piles to be installed. The vehicle 12 and cradle 15 also move along at the same time. The next pair of piles 11 A, 1 IB are then removed from the cradle and installed into the ground by repeating the procedures shown in figures 2 to 7.

[0053] Figures 8 to 11 show use of the twin mast pile installation apparatus 22 to install the piles 11 A, 1 IB into the ground at an angle to each other. The piles 11 A, 1 IB are loaded onto their respective driveshafts 23, 24 of the twin mast installation apparatus 22 using the same procedure as described with reference to figures 2, 3 and 4. However, in order to install pile 11 A into the ground at a non-vertical angle, rather than moving the twin mast pile installation apparatus 22 to the orientation as shown in figure 5, the twin mast pile installation apparatus 22 is moved to the orientation as shown in figure 8. In figure 8, the pile 11 A is angled at the required angle for installation on the ground. Drive motor 25 is then operated to turn the driveshafts 23 and the pile 11 A and cause installation of the pile downwardly at an angle. This is shown in figure 9. Once the pile 11 A has been inserted to the desired depth, the driveshaft 23 is retracted from the shaft of the pile 11 A. The twin mast pile installation apparatus 22 is then rotated to bring pile 1 IB to the desired angle for installation into the ground and the drive motor 26 is operated to turn the driveshaft 24 and the pile 1 IB, which causes extension of the pile 1 IB downwardly at the angle as shown in figure 10. Once the pile 1 IB has been fully inserted into the ground to the desired depth and at the desired angle, the driveshaft 24 is retracted from the shaft of the pile 1 IB. Figure 11 shows the installed piles 11 A, 1 IB with the driveshafts of the twin mast pile installation apparatus 22 being withdrawn from the shafts of the piles.

[0054] The twin mast pile installation apparatus 22 may then be re-loaded with piles 11 A, 1 IB using a similar method to that as described with reference to figures 2, 3 and 4. The next pair of piles by then be inserted into the ground in the manner as shown in figures 8 to 11.

[0055] The apparatus may be precisely located using GPS location. The apparatus may have advanced software to allow semi-autonomous or autonomous operation.

[0056] In embodiments of the present invention, the cradle is mounted on a trailer and is used to store and move a number of pairs of piles. The piles may be blade piles available from Blade Pile Pty Ltd, of Burleigh Heads, Queensland, Australia. Screw piles may also be used. The piles are stacked into spaced rows on the cradle, with the piles 11 A being positioned in a row that is located above the piles 1 IB. The cradle allows for easy stacking of the piles and it also allows for removal of a pair of piles at a simultaneous time by use of the twin mast pile installation apparatus.

[0057] Whilst the piles 11 A, 1 IB were being installed into the ground, the cradle 15 and trailer 28 were moved forward by distance equivalent to the next spacing of the next pair of piles to be installed into the ground. After installation, the installing apparatus 10 is also moved to the next installation position. The apparatus 22 is moved back to the position shown in figure 22 and the processes described with reference to figures 2 to 7 or figures 2 to 4 and 8 to 11 and is repeated to install the next pair of blade piles into the ground. [0058] When the operator removes the last pair of piles from the cradle, the empty cradle and trailer are removed and a second cradle and trailer that is fully stacked with piles replaces the first cradle and trailer. In this manner, the second trailer can be re-stacked with piles at a holding yard and then transported to the installation site whilst the first trailer is being emptied of piles. This is advantageous in that commercial solar farms often cover a very large area, for example, hundreds of acres. There has proven to be significant logistical difficulties in moving piles from a holding yard to the site of installation, which can be located very long distances away from the holding yard. An aspect of the present invention allows for efficient loading of the cradle and trailer at the holding yard, followed by easy transport of the loaded cradle and trailer to the site of installation. By proper scheduling loading and transport of cradles from the holding yard to the installation site, the installation apparatus can always have a ready supply of piles to be installed. A further advantage of this embodiment of the invention is that Occupational Health & Safety issues are significantly reduced because the operator of the excavator can load the piles onto the twin mast pile installation apparatus and install the piles without requiring any on- ground personnel to assist in this endeavour. As a result, personnel are removed from the ground near the installation site, which is significantly decreases Occupational Health & Safety risks associated with installing the piles. All operators can also be located in air-conditioned cabins of vehicles, which is a significant advantage if the solar farm is being installed in hot regions.

[0059] The drawings accompanying this specification show installation of a pair of piles. It will be appreciated that the present invention also encompass installation of single piles. In those instances, a single mast pile installation apparatus may be used.

[0060] In the present specification and claims (if any), the word ‘comprising’ and its derivatives including ‘comprises’ and ‘comprise’ include each of the stated integers but does not exclude the inclusion of one or more further integers.

[0061] Reference throughout this specification to ‘one embodiment’ or ‘an embodiment’ means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases ‘in one embodiment’ or ‘in an embodiment’ in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

[0062] In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims (if any) appropriately interpreted by those skilled in the art.