MODULAR RAFT SYSTEM

TECHNICAL FIELD

This disclosure relates to load-carrying rafts. The disclosure has particular, although not exclusive, application to floating photovoltaic panel installations and associated equipment.

BACKGROUND

Many organisations and communities are turning to solar energy to supply at least some of their energy requirements. While land-based solar energy projects are not new, solar farms which are constructed on floating rafts on a water body (e.g. pond, lake or dam), termed "floating solar", is emerging partly because it has an additional benefit of reducing evaporative loss from the water body.

While a variety of different raft systems exist, they suffer from drawbacks, such as being inefficient to transport from their manufacture site to the water body, being difficult to assemble, having a wide range of buoyancy in different weather conditions and having coupling arrangements which don't sufficiently account for wave and wind action.

There is a need for a suitable raft system on which large-scale solar panel arrays can be deployed. It is desirable that the raft system or aspects of it ameliorates one or more of the drawbacks identified above.

SUMMARY OF THE DISCLOSURE

In accordance with a first aspect there is disclosed a fastener for coupling together first and second raft modules, the fastener having:

(a) a body with a thread extending from a first end of the body and which thread is co- operable with a thread associated with the first raft module; and

(b) a head disposed on a second end of the body and having at least one formation that is configured to interact with the second raft module to resist rotation of the fastener.

The formation may include a resiliently deformable member which interacts with the second raft module. The formation may be radially directed. The head may be a circular flange and the formation may comprise a void in the flange and a segment that is radially outboard of the void and which forms part of the perimeter of the flange.

The segment may include a seat and resilient load members connecting the seat to the remainder of the flange, whereby deflection of the seat causes deflection of the load members which apply a counteractive force on the seat which resists further deflection of the seat.

The seat and the load members may be configured so that the load members in part a torque on the seat as part of the counteractive force.

The seat may extend axially toward the body from the load members.

The head may be configured to engage a tool for rotating the fastener to control engagement of the thread with a thread associated with the first raft module.

In accordance with a second aspect there is disclosed a fixing member that is configured for coupling with a raft module to form a fixing point for a fastener, the fixing member having a body with a first end that includes first formations which co-operate with a raft module to retain the fixing member in connection with the raft module.

The fixing member having a thread that is co-operable with other threaded fasteners associated with another raft module to enable coupling of the raft module with the other raft module.

It will be appreciated that, when the fixing member is retained in connection with the raft module, the thread of the fixing member is a thread associated with the raft module. The thread is configured to co-operate with the threaded fastener disclosed above for coupling together first and second raft modules.

The fixing member may have second formations which are configured to interact with the raft module to resist rotation of the fixing member.

The body may have an internal bore and the thread forms the surface of the internal bore. The body may have a flange at one end which includes the second formations and a snap-fit formation at the other end which enables releasable coupling of the fixing member to a raft module.

The flange has an opening to the internal bore, the opening has a perimeter which includes at least one third formation that is configured to interact with another threaded fastener received within the internal bore to resist relative rotation of the fixing member and the other threaded fastener.

In accordance with a third aspect, there is disclosed an anchor member for coupling a structure to a raft module, the anchor member having a body with a flange disposed at one end, the body having:

(a) a thread that is configured to couple with a thread associated with the raft module; and

(b) a bore extending axially within the body and opening at the flange for receiving a fastener associated with the structure.

The flange may include a formation that is configured to resist rotation of the anchor member relative to the thread associated with the raft module.

The formation may include a resiliently deformable member.

The flange may be circular and may include a void in the flange with a radially outboard segment which forms part of the perimeter of the flange and wherein the segment is configured to permit positive thread in engagement with the thread associated with the raft module and to resist negative thread engagement with the threat associated with the raft module.

This segment may be configured with at least one sawtooth formation of the segment and which segment can be deflected radially inwardly into the void to permit positive thread engagement with the thread associated with the raft module.

The bore of the anchor member has a thread for receiving a threaded fastener associated with the structure.

The fastener according to the first aspect may include an axial bore that is configured with a thread to receive an anchor member according to the third aspect, the axial bore having an opening at the flange and wherein the opening includes at least one perimeter formation that is configured to interact with the rotation-resisting formation of the anchor member.

The perimeter formation of the fastener may be a sawtooth formation.

The fixing member according to the second embodiment may include an internal bore that has an opening at the flange and wherein the opening includes at least one perimeter formation that is configured to interact with the rotation-resisting formation of the anchor member.

The perimeter formation of the fixing member may be a sawtooth formation.

According to a fourth aspect, there is provided a kit for forming a raft from a plurality of raft modules, the kit including;

(a) a plurality of fasteners according to the first aspect disclosed above; and

(b) a plurality of fixing members according to the second disclosed above.

The kit may further include a plurality of anchor members according to the third aspect disclosed above.

The kit may further include a plurality of raft modules adapted for coupling by the fasteners and the fixing members.

According to a fifth aspect, there is provided a buoyant raft module for coupling with like modules to form a load-bearing raft in a single layer of modules, the raft module comprising;

(a) a core;

(b) a coupling frame at a periphery of the core; and where in the coupling frame is configured to complement a coupling frame of an adjacent buoyant module to form a generally continuous raft surface across the adjacent raft modules.

The raft module may include a plurality of cavities in the core which co-operate with fasteners to form a loading point for securing a load. The raft module may include a plurality of cavities in the coupling frame which co operate with fasteners to couple the raft module with another raft module.

The raft module may include a plurality of cavities in the coupling frame which are co- operable with fasteners to form a loading point for securing a load.

The cavities may be configured to cooperate with the fastener disclosed in the first aspect above, a fixing member of the second aspect disclosed above and/or an anchor member of the third aspect disclosed above.

Each cavity may include a well having a flange-receiving seat and a throat portion extending from the seat to a formation that is co-operable with a fastener to retain the fastener in the cavity.

The coupling frame may have a ledge portion and a platform portion and the ledge portion may overlaps the platform portion of an adjacent raft module and the platform portion underlap a ledge portion of an adjacent raft module.

The raft module may include a plurality of connection points that tether a top surface 140 of the raft module to an underneath surface 142 of the raft module.

The cavities may extend from a top side of the core and the ledge portion and may extend from an underside of the platform portion.

The cavities may include elements which are configured to co-operate with rotation- resisting formations of the fastener and the fixing member to resist rotation of the faster and the fixing member.

The elements may comprise a projection that extends into the volume of the seat.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of each of the aspects disclosed above will be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is an oblique isometric view from below of an embodiment of a fastener according to the first aspect disclosed above; Figure 2 is an oblique isometric view from above of the fastener in Figure 1; and Figure 3 is a side plan view of the fastener in Figure 1;

Figure 4 is a cross-sectional view of the fastener in Figure 3 along the line A-A;

Figure 5 is a top plan view of the fastener shown in Figure 1;

Figure 6 is an underneath plan view of the fastener shown in Figure 1;

Figure 7 is an oblique isometric view from above of a fixing member according to the second aspect disclosed above;

Figure 8 is an oblique isometric view from below of the fixing member in Figure 7;

Figure 9 is a side plan view of the fixing member in Figure 7;

Figure 10 is a cross-sectional view of the fixing member in Figure 9 along the line B-B;

Figure 11 is a top plan view of the fixing member shown in Figure 7;

Figure 12 is an underneath plan view of the fixing member shown in Figure 7;

Figure 13 is an oblique isometric view from below of an embodiment of an anchor member according to the third aspect disclosed above;

Figure 14 is an oblique isometric view from above of the anchor member in Figure 13; and

Figure 15 is a side plan view of the anchor member in Figure 13;

Figure 16 is a cross-sectional view of the anchor member in Figure 15 along the line C-C;

Figure 17 is a top plan view of the anchor member shown in Figure 13;

Figure 18 is an underneath plan view of the anchor member shown in Figure 13; Figures 19 and 20 are oblique isometric views from above and below respectively of a raft module according to a fourth aspect;

Figure 21A is a top plan view of the raft module in Figure 19 with fixing members and anchor members fitted to the raft module;

Figure 21B is a magnified view of a circled section of the raft module in Figure 21A; and

Figure 22 is cross-sectional view of two raft modules (of the form shown in Figure 19) coupled together by co-operation of the fastener in Figure 1 with the fixing member in Figure 7 and with the anchor member of Figure 13 in position for fastening a structure.

Figure 23 is an oblique isometric view from above of another embodiment of a fastener according to the first aspect disclosed above;

Figure 24 is an oblique isometric view from below of the fastener in Figure 23; and Figure 25 is a side plan view of the fastener in Figure 23;

Figure 26 is a cross-sectional view of the fastener in Figure 25 along the line D-D;

Figure 27 is a top plan view of the fastener shown in Figure 23;

Figure 28 is an underneath plan view of the fastener shown in Figure 23;

Figure 29 is an oblique isometric view from below of another embodiment of an anchor member according to the third aspect disclosed above;

Figure 30 is an oblique isometric view from above of the anchor member in Figure 29; and

Figure 31 is a top plan view of the anchor member shown in Figure 29;

Figure 32 is an underneath plan view of the anchor member shown in Figure 29;

Figure 33 is a side plan view of the anchor member in Figure 29; Figure 34 is a cross-sectional view of the anchor member in Figure 15 along the line E-E;

Figure 35 is an oblique isometric view from above of a fixing member according to the second aspect disclosed above;

Figure 36 is an oblique isometric view from below of the fixing member in Figure 35; Figure 37 is a side plan view of the fixing member in Figure 35;

Figure 38 is a cross-sectional view of the fixing member in Figure 37 along the line F-F;

Figure 39 is a top plan view of the fixing member shown in Figure 35;

Figure 40 is an underneath plan view of the fixing member shown in Figure 35;

Figure 41 is an oblique isometric view from above of a connector cover;

Figure 42 is an oblique isometric view from below of the connector cover in Figure 41;

Figure 43 is a side plan view of the connector cover in Figure 41;

Figure 44 is a cross-sectional view of the connector cover in Figure 37 along the line G- G;

Figure 45 is a top plan view of the connector cover shown in Figure 41;

Figure 46 is an underneath plan view of the connector cover shown in Figure 41;

Figures 47 and 48 are oblique isometric views from above and below respectively of a raft module according to a fourth aspect;

Figure 49 is a magnified view of a section of the raft module marked A in Figure 51;

Figure 50 is a magnified view of a section of the raft module marked B in Figure 51;

Figure 51 is a top plan view of the raft module in Figure 47 with fixing members and anchor members fitted to the raft module in sections A and B; Figure 52 is an underneath plan view of the raft module in Figure 47;

Figure 53 is a side view of two raft modules in Figure 47 in an overlapping arrangement to form a raft;

Figure 54 is cross-sectional view of two raft modules (of the form shown in Figure 47) coupled together by co-operation of the fastener in Figure 23 with the fixing member in Figure 35 and also with the fixing member fitted with the anchor member of Figure 29 in position for fastening a structure; and

Figure 55 is a cross-sectional view of stacked raft modules (of the form shown in Figure 47).

DETAILED DESCRIPTION

Embodiments will now be described in the following text which includes reference numerals that correspond to features illustrated in the accompanying Figures. To maintain clarity of the Figures, however, all reference numerals are not included in each Figure.

Referring to figures 1 to 6, there is shown a fastener in the form of a bolt 10 for coupling together first and second raft modules. The bolt has a body 12 in the form of a hollow tube having a lower portion 14 with an external thread 16 extending from a first end and an upper portion 18 having an internal thread 20. The bolt 10 further has a head in the form of a flange 22 on a second end of the body remote from the first end. The flange 22 includes a formation that is configured to interact with a raft module 120 (Figures 19 to 22) to resist rotation of the bolt 10.

The flange 22 comprises an annular base wall 24 which is disposed on the tube adjacent the second end. Arc walls 26 extend co-axially of the body 12 from the base wall 24 to a location that substantially coincides with the second end of the body 12 and an annular rim 30 extends radially outwardly from the arc walls 26. A series of partitions 28 are located in the space between the arc walls 26 and the body 12 to define alternating recesses 44 and voids 36. The recesses 44 are closed to their base by the base wall 24, but the voids 36 coincide with the gaps between adjacent arc walls 26 and open radially outwardly. An outer periphery of the base wall 24 includes detents 46 in the location of the voids. The rim 30 forms a closed loop around the upper edge of the arc walls 26 and is connected to the body 12 by the partitions 28. The rim 30 includes segments which each comprise a seat 32 and adjacent arms 34. The seats 32 are aligned with the detents 46 and extend downwardly from the rim 30 co-axially with the body 12.

The bolt 10 is preferably formed of resilient material such that the segment is deformable. Specifically, the seats 32 interact with protuberances 144 on the raft modules 120 to deflect the seats 32 radially inwardly and upwardly so that the arms 34 are twisted slightly. The resilient nature of the arms 34 means that they impart a counteractive return force, i.e. a torque, on the seats 32 which resists further displacement of the seats 32 and, therefore resists rotation of the bolt 10 relative to the raft module 120. In additional to the rotational deflection of the arms 34, they may also be deflected radially inwardly into the void 36 so that there will be an compound counteractive force applied by the arms 34 to the seat 32 which involves the torque force and a compression force as they resist radially inward deflect of the seat 32.

The deflection of the segment establishes a threshold force which is required to be overcome to cause further rotation of the bolt 10. This means that the segment acts to resist rotation of the bolt 10 and, therefore, resists unscrewing of a threaded connection as a result of persistent wave and/or wind action on the raft modules 120. This arrangement avoids the need for locking pins or additional fasteners (e.g. rivets) that anchor the bolt 10 relative to another part of the raft. The applicant anticipates that this bolt 10 will reduce the time required to construct and deploy a raft.

Having regard to Figures 7 to 12, a fixing member is shown in the form of a plug 50 having a hollow body 52 with an internal thread 54. A lower portion of the body 52 is formed as two separate arcuate legs 56, each of which has a bead 58 which defines a shoulder 57 at a rearward side and a bevel 60 on a leading side. The legs 56 are resilient enough to be deflected inwardly toward each other such that the legs 56 can pass a narrow opening and then expand again so the shoulder 57 abuts with the opening, thereby holding the plug 50 within the opening.

An annular flange 62 is disposed on the other end of the plug 50 opposite to the legs 56. The flange 62 extends radially outwardly from the body 52 and has a base wall 64 extending radially outward from the body 52 and a series of alternating seats 68 and arc walls 66 that extend coaxially from the base wall 64 toward the top of the body 52. The flange 62 further includes a series of partitions 70 connecting the body 52, base wall 64 and arc walls 66 or seats 68 to define a series of recesses 72 about the top of flange 62.

The top of the body 52 includes an opening 74 into the hollow of the body 52. A perimeter 76 of the opening 74 is circumscribed by a sawtooth formation 78.

An anchor member in the form of sleeve screw 80 is shown in Figures 13 to 18. The sleeve screw 80 has a tubular body 82 in the form of a sleeve with an external thread 84 and an elongate, hollow hub 86 disposed within the body 82. The dimensions of the body 82 and the external thread 84 are selected to mate, i.e. threadedly engage, with the internal thread 20 of the bolt 10 (Figures 1 to 6) and internal thread 54 of the plug 50 (Figures 7 to 12) as shown in Figure 22.

The hub 86 is centered along the rotational axis of the body 82 by a series of radial spokes 100 that connect the hub 86 to the inner wall of the body. In this embodiment, there are four elongate spokes 100 which are equidistantly spaced about the hub 86.

The hollow hub 86 defines a bore 88 which has an internal thread 90 for mating, i.e. threadedly engaging, with a threaded fastener, such as a screw or bolt for fastening a structure to the sleeve screw 80. It will be appreciated, however that the internal configuration of the bore may be adapted to fit with other types of fasteners to secure a structure to the sleeve screw 80. For example, the bore may be configured with features that co-operate with a snap-fit, interference or friction fasteners. The sleeve screw 80, therefore, is not limited to co-operating with threaded fasteners.

The sleeve screw 80 includes a disc-shaped cap 92 that includes a series of apertures 102 for receiving a tool that can be used to rotate the sleeve screw 80, for example to mate with the internal threads 20, 54 of the bolt 10 or the plug 50, respectively. The cap 92 includes a circumferential wall 104 having a series of discrete sawtooth formations 106. In this embodiment, there are four discrete formations 106 disposed equidistantly about the circumferential wall 104 of the cap 92. Inboard of each formation 106 is an arcuate slot 110 which extends through the cap 92 from the top to the underside. The slot 110 makes a radially outboard segment 108 of the cap 92 deflectable so that the formation 106 can brought into contact with the sawtooth formations 42, 78 at the perimeter 40, 76 of the openings 38, 74 in the bolt 10 and the plug 50 respectively to provide a rachet interaction which permits rotation of the sleeve screw 80 in a direction which increases mating of the sleeve screw 80 with the internal thread 20, 54 of the bolt 10 and the plug 50 (i.e. positive threaded engagement) and which resists unscrewing of the sleeve screw 80 with the internal threads 20, 54 of the bolt 10 and the plug 50 (i.e. negative threaded engagement).

A raft module 120 is shown in Figures 19 to 22. The raft module 120 comprises a central core in the form of a block 122 from which extends on two adjacent sides an upper panel 124 and from which extends on two other adjacent sides a lower panel 126 which, in use, faces downwardly into a body of water. A top surface 140 of the raft module 120 comprises an upper surface of the block 122 in combination with the upper panel 124. The top surface 140 further comprises an upper surface of the lower panel 126. An underneath surface 142 of the raft module 120 comprises the underside of the block 122 in combination with an underside of the lower panel 126, plus and underside of the upper panel 124.

The top surface 140 of the raft module 120 is shown in more detail in Figures 21A and 21B. In particular, it can be seen that the raft module 120 includes an array of cavities in the form of connection apertures 128 formed in the upper and lower panels 124, 126 and anchor apertures 130 formed in the block 122.

The anchor aperture 130 is shown in Figure 22 extending from the top surface 140 to the underneath surface 142. The anchor aperture 130 opens at the top surface 140 in a seat, in the form of a step 132, recessed from the top surface 140. The anchor aperture 130 then transitions into a throat in the form of a narrowed passage 134 which terminates at an inverted shoulder 136 which acts as a ledge against which the bead 58 of the plug 50 abuts in use. From there, the anchor aperture 130 transitions into a channel that opens at the underneath surface 142 of the block 122.

As can be seen in Figure 22, the plug 50 is located in the anchor aperture 130 by forcing the body 52 downwardly into the passage 134 so that the legs 56 deform to an extent to pass the bead 58 through the passage 134 so the bead 58 engages the shoulder 136.

The plug 50 is properly fitted when the rotation resisting projections of the raft module 120, in the form of protuberances 144 at the step 132, are located in the seats 68 at the perimeter of the flange 62 (Figure 21B). The sleeve screw 80 is then screwed into the body 52 by engaging the external thread 84 of the sleeve screw 80 with the internal thread 54 of the plug 50. The segments 108 deflect under positive thread engagement, thereby allowing the teeth 106 to skip over the sawtooth formation 78 until the plug 50 is properly located when the sleeve screw 80 cannot be screwed in further. At this point, the teeth 106 of the sleeve screw 80 are engaged with the sawtooth formation 78 of the plug 50 and, therefore, the sleeve screw 80 is resisted from negative thread engagement (i.e. unscrewing) by interaction of the teeth 106 and the sawtooth formation 78. This arrangement of the plug 50 and the sleeve screw 80 allows structures to be secured to the block 122 with an appropriate fastener that engages the internal thread 90 of the bore 88. Such structures may include hand-rails and support frames for photovoltaic panels. As explained above, the fastener used to secure a structure to the sleeve screw 80 does not need to be a threaded fastener, but may instead be a snap-fit fastener or other type of fastener with the sleeve screw 80 adapted appropriately to co-operate with the selected fastener.

It will be appreciated that with the tubular body 82 of the sleeve screw 80 located in the plug 50 as shown in Figure 22, the tubular body 82 prevents the legs 56 from deflecting inwardly and releasing the plug 50 from the anchor aperture 130. With rotation of the screw sleeve relative to the plug 50 resisted by the teeth 106 and the sawtooth formation 78, wave and wind action is unlikely to cause the sleeve screw 80 to unscrew from the plug 50, so it is anticipated that the structure will remain secured to the raft module 120.

The connection aperture 128 is the same as the anchor aperture 130 apart from being formed in the upper and lower panels 124, 126 only and apart from having a shorter channel 138 on account of the upper and lower panel 124, 126 having a reduced thickness compared to the block 122. Otherwise, the connection aperture 128 has the same step 132, passage 134 and shoulder 136 as the anchor aperture 130. It will be appreciated, that the connection apertures 128 in the upper panel 124 have the step 132 opening to the top surface 140 of the raft module 120 and in the lower panel 126 the connection apertures 128 are inverted with the step 132 opening to the underneath surface 142 of the raft module 120.

The raft module 120 shown in Figures 19, 20 and 21 has a square array of 9 anchor apertures 130 in the block 122 and seven connection apertures 128 along each of the upper and lower panels 124, 126. However, the block 122 and the panels 124, 126 may include more or fewer apertures 128, 130. The number of apertures 128, 130 may vary with the size of the raft module 120. The apertures 128, 130 provide connection points between the top surface 140 and the underneath surface 142 so that the shape of the raft modules 120 won't vary significantly with variations in temperature. Connecting adjacent raft modules 120 involves overlapping the upper panel 124 of one raft module 120 with a lower panel 126 of another raft module 120 and aligning the respective connection apertures 128. A plug 50 is located in the connection aperture of the lower panel 126 and a bolt 10 is directed downwardly through the connection aperture 128 of the upper panel 124 so that the external thread 16 engages the internal thread 54 as shown in Figure 22. The bolt 10 is properly secured with the plug 50 when the plug 50 is pulled upwardly to be firmly seated in the step 132 with the protuberances 144 located in seats 68 and the same with the protuberances 144 of the upper panel 124 being located in the seats 32 of the bolt 10. Doing so causes the body 12 of the bolt 10 to be retained in the plug 50 so as to prevent the legs 56 deflecting to release the plug 50 from the shoulder 136 of the connection aperture 128.

This connection process involves linking connection apertures 128 denoted A in Figure 21A with a first adjacent raft module 120, linking connection apertures 128 denoted B with a second adjacent raft module 120, linking connection apertures 128 denoted C with a third adjacent raft module 120, linking connection apertures 128 denoted D with a fourth adjacent raft module 120, linking connection aperture 128 denoted E with a fifth adjacent raft module 120 and linking connection aperture 128 denoted F with a sixth adjacent raft module 120. Accordingly, unless a raft module 120 is located on the perimeter of a raft, each raft module 120 will be linked to six adjacent raft modules 120.

Alternatively, some of the connection apertures 128 may be fitted with the bolt 10 to connect with an adjacent raft module 120 and the remaining connection apertures in the upper panel 124 may be fitted with a plug 50 and sleeve screw 80 to form an anchor point to which structures supported by the raft may be anchored and the remaining apertures 128 in the lower panel 126 may be left vacant. For example, the bolt 10 may be fitted to alternate connection apertures 128 in the upper panel 124 and plugs 50 with sleeve screws 80 may be fitted to the other connection apertures 128 and plugs may be fitted in connection apertures 128 of the lower panel 126 to co-operate with bolts in connection apertures 128 of an adjacent raft module 128. As explained above, the sleeve screw 80 may be fitted to the bolts 10 which are located in connection apertures 128 to provide additional anchor points for securing structures supported by the raft module 120.

This interconnectivity between a raft module 120 and the raft modules to which it is connected spreads forces through a raft formed of the modules 120 and thereby reduces stress localization (i.e. stress concentration) which can lead to connections failing and rafts breaking up under severe weather conditions. It is for this reason that a raft formed with the modules is preferably formed as a continuous array of modules, i.e. without gaps, such as gaps underneath photovoltaic panels.

Alternative raft module and connectors are shown in Figures 23 to Y. These connectors and raft module are similar in overall functions to the bolt 10, plug 50, sleeve screw 80 and raft module 120, but they include some alternative features which may be combined with the bolt 10, plug 50, sleeve screw 80 and raft module 120 to arrive a new embodiments. In other words, the features of the embodiments described above are not exclusive to those embodiments and may be combined with other features of the embodiments described below. Similarly, features of the embodiments described below are not exclusive to those embodiments and may be combined with other features of the embodiments described above.

Figure 23 to 28 show an alternative embodiment of a fastener in the form of a bolt 210 for coupling together first and second raft modules. The bolt 210 has a body 212 in the form of a hollow tube. The body has a lower portion 214 with an external thread 216 extending from a first end and an upper portion 218. The bolt 210 further has a head in the form of a flange 220 on a second end of the body 212 remote from the first end.

The flange 220 comprises an annular base wall 222 which extends from the second end of the body 212. An annular rim 224 extends axially from a perimeter of the annular base wall 222. The annular rim 224 extends from the annular base wall 222 in a direction away from the body 212. A lip 236 projects radially outwardly from the annual rim. Radial partitions 226 extend from the annular rim 224 to a keying hub 228. The partitions are joined with the annular rim 224 and the annular base wall 222. This reinforces the flange 220.

The keying hub 228 is configured to co-operate with a tool to enable tightening or loosening of the bolt 210. In this embodiment, the keying hub 228 comprises four arc walls 230. Each arc wall 230 is a segment of the same circle and is spaced apart from adjacent arc walls 230 by a respective gap. Each gap is bound on one side by an end panel 234 on each other side by respective drive walls 232 which connect the end panel 234 to the arc walls 230. The tool has a formation that is shaped to complement the shape of the keying hub 228. In particular, the tool has projections which fit within the gaps and bear against the drive walls 232 when a torsional force is applied through the tool. The torsional force is transferred through the projections to the drive walls 232 which causes the bolt to rotate. The keying hub 228 extends from the annular base wall 222 beyond the level of the annular rim 224.

The body 212 comprises a hollow tube. The upper portion 218 of the body 212 includes a structural frame 240. The structural frame includes a series of axial ribs 242 projecting radially from the body. It also includes a series of annular ribs 246 which intersect the axial ribs 242. The annular ribs 246 and axial ribs 242 extend from the body 212 by extent which provides a close fit with apertures formed in raft module and in which the bolts are designed to fit for coupling adjacent modules together. It will be appreciated, however, that alternative rib configurations may be adopted to provide the same effect. For example, the ribs may be arranged helically around the body 212, for example. In another example, the rib may not intersect and may instead be formed as zig-zags about the body 212.

The interior of the body 212 includes a threaded coupling portion 250. This threaded coupling portion 250 enables the bolt to couple with bolts and screws used to fasten structures to the raft module, for example. The threaded coupling portion 250 includes a central sleeve 252 having a lower threaded section 254 and an upper pilot section 256. The upper pilot section 256 is blank, in that it does not include any features that couple with a bolt. Instead, the pilot section 256 serves to align the bolt or screw with the threaded section 254 to reduce the chance of cross threading. The central sleeve 252 is held in position within the body 212 by axial braces 258 which extend between the central sleeve 252 and the body 212 in a radial direction. The central sleeve 252 may further be held in position by radial braces 260. The radial braces 260 comprise annular segments that extend from the central sleeve 252 to the body 212 and extend between and join adjacent axial braces 258.

While the embodiment shown in Figure 23 and described above may be formed by injection moulding, alternative construction methods may be adopted. For example, the central sleeve 250 may be formed as a brass or stainless steel insert having an internal thread and which insert is over-moulded with plastics to form the insert as part of the bolt 210. In an alternative construction method, the threaded coupling portion 250 is formed by injection moulding separately from the remainder of the bolt 210 and is coupled with the remainder of the bolt 210 by a friction fit. That is, the threaded coupling portion 250 is inserted into the body where friction fit means retains the threaded coupling portion 250 as part of the bolt 210. Such friction fit means may comprise crushable ribs projecting into the hollow interior of the body 212. A further alternative involves injection moulding the entire bolt 210, except for the threaded section of the central sleeve 252. Instead, the interior surface of the sleeve will be formed as a blank surface and coupling with the bolt or screw would involve using self tapping screws to engage the sleeve 252.

Between the thread 216 and the structural frame 240 is a band 262 that includes a series of detents 264. The band 262 comprises a radially thicker section of the body 212 so that the detents 264 protect radially outwardly further than the thread 216. The detents 264 are arranged to extend axially of the body 212. The detents 264 include a bevelled end 266 adjacent to the thread 216. The detents 264 further include sides 268 which increase in height with the bevel. The sides 268 are inclined from the band 262 and come together at a ridgeline to provide a triangular profile beyond the bevelled end 266.

Having regard to Figures 35 to 40, a fixing member is shown in the form of a plug 300 having a hollow body 302 with an internal thread 304. The internal thread 304 is adapted to receive and mate with thread 216 of the bolt 210. A lower portion of the body 52 is formed as four separate arcuate legs 306. Each leg 306 has a bead 320 which extends radially outwardly from the body 302. The bead defines a shoulder 322 at a rearward side and an outer bevel 326 on a leading side. The legs 306 are resilient enough to be deflected inwardly toward an opposing leg 306 such that the legs 306 can pass a narrow opening and then expand again so the shoulder 322 abuts with the opening, thereby holding the plug 300 within the opening.

Each leg 306 includes a series of channels 308. The channels 308 are spaced apart and coaxially aligned with the body 302. Each channel 308 includes a taper 310 which has an increasing channel width from the end of the body to a position level with the shoulder 322. The taper 310 is located on an inner bevel 324 of the body 302. Each channel 308 also has a main section 312 which is configured to receive a detent 264 of the bolt 210. More specifically, each channel 308 includes inclined sides 314 which are arranged to complement the shape of the detents 264. When the internal thread 304 is engaged with the thread 216, the detents 264 will begin to engage the channels 308. The taper 310 increases the level of contact between the detents 264 and the channels 308 as engagement between the plug 300 and the bolt 210 increases. When fully engaged, a number of the detents 264 will rest in the channels 308. The profile of the detents 264 interacts the sides 314 of the channels 308. This interaction resists relative rotational movement between the bolt 210 and the plug 300, thereby assisting to retain them in an engaged state.

In this embodiment, each leg 306 includes four channels 308. This number is selected to ensure that as many of the detents 264 are seated within the channels 308 for any given angular displacement of the plug 300 relative to the bolt 210.

An annular flange 330 is disposed on the other end of the plug 300 opposite to the legs 306. The flange 330 extends radially outwardly from the body 302 and has an annular base wall 332 extending radially outward from the body 302. The flange 330 further includes an annular rim which extend axially from the perimeter of the annular base wall 332. The annular rim 334 comprises a series of alternating seats 336 and arc walls 338. In this embodiment, there are four seats 336 equally spaced about the annular rim 334 and arc walls 338 extending between the seats 336. The seats 336 are configurated to interact with anti-rotation members of a raft module so that torque applied to the plug 300, for example due to persistent wave and wind action, is counteracted by the interaction between the seats 336 and the anti-rotation members. The flange 330 further includes a series of partitions 340 extending from the annular rim to a rachet hub 342. The rachet hub 342 extends co-axially of the body 302. It has an inner perimeter 344 that includes a rachet formation 346. In this embodiment, the rachet formation is a sawtooth formation. The rachet hub 342 extends proud of the partitions 340 and the annular rim 334.

An axially upper end of the annular rim 334 includes a lip 350. The lip 350 projects radially outwardly from the annular rim 334. In this embodiment, the lip 350 is continuous about the annular rim 334. However, in other embodiments, the lip 350 may be discontinuous. For example, the lip 350 may present only on the arc walls 338 and may be absent from the seats 336.

Another embodiment of an anchor member in the form of a sleeve screw 500 is shown in Figures 28 to 34. The sleeve screw 500 has a tubular body 502 in the form of a sleeve with an external thread 504. Flange projections 506 extend from the end of the body opposite to the flange. Projecting from the same end of the body is a keying hub 508. In this embodiment, the keying hub 508 in the same form as described above in respect of the bolt 210 so that the tool which can be used to drive the bolt 210 can also be used to drive the sleeve screw 500. The keying hub 508 is configured to co-operate with a tool to enable tightening or loosening of the sleeve screw 500. In this embodiment, the keying hub 508 comprises four arc walls 510. Each arc wall 510 is a segment of the same circle and is spaced apart from adjacent arc walls 510 by a respective gap. Each gap is bound on one side by an end panel 514 on each other side by respective drive walls 512 which connect the end panel 514 to the arc walls 510. The tool has a formation that is shaped to complement the shape of the keying hub 508 and the keying hub 228 of the bolt 210. In particular, the tool has projections which fit within the gaps and bear against the drive walls 512 when a torsional force is applied through the tool. The torsional force is transferred through the projections to the drive walls 512 which causes the sleeve screw 500 to rotate. The keying hub 508 extends from an end of the body 502.

The dimensions of the body 502 and the external thread 504 are selected to mate, i.e. threadedly engage, with the internal thread 304 of the plug 300. The screw sleeve 500 further includes formations 518 that interact with the plug 300 to inhibit relative rotation between the plug 300 and the sleeve screw 500. The formations 518 are configured to provide a first level of resistance during engagement of the screw sleeve 500 with the plug 300 and a second, higher level of resistance to disengagement of the screw sleeve 500 from the plug 300. The formations include resilient arms 526 which are configured to urge the formations 518 into contact with the plug 300. The formations 518 are located on the screw sleeve 500 to interact with the rachet hub 346 when the plug 300 and the screw sleeve 500 are threadedly the engaged.

The formations 518 include pawls 520 which are formed to interact with the rachet hub 346. Each pawl 520 comprises a ramp 522 and a stop wall 524. Each pawl 520 is connected to adjacent end panels 514 by arms 526. This configuration forms a bridge between adjacent end panels 514. Furthermore, the arms 526 are bowed. The bowed form enables the formation 518 to deflect radially inwardly toward an associated arc wall 510. In doing so, the pawl 520 is enabled to ride over the rachet formation 346 when the plug 300 and sleeve screw 500 are being engaged. The deflection is a resilient deflection so that the pawl 520 is urged back to its original position and thereby is pushed against the rachet formation 346. The resistance experienced during engagement of the screw sleeve 300 with the plug 500 is generated by from the resilient deflection of the ramp riding over the rachet formation 346. The resistance during disengagement of the screw sleeve 500 from the plug 300 is generated by the stop wall 524 abutting the rachet formation 346. This resistance is higher because the stop wall 524 is oriented generally perpendicular to the rotation direction for disengaging the screw sleeve 500 from the plug 300 and because the stop wall 524 abuts an oppositely oriented part of the rachet formation 346. The overall experience of a user is that the rachet interaction between the screw sleeve 500 and the plug 300 is that it permits rotation of the sleeve screw 500 in a direction which increases mating of the sleeve screw 500 with the plug 300 (i.e. positive threaded engagement) and which resists unscrewing of the sleeve screw 500 from the plug 300 (i.e. negative threaded engagement).

Like the bolt 210, the screw sleeve 500 includes a threaded coupling portion 530 within the body 502 to enable fastening of structures to the sleeve screw 500 in the same manner structures are fastened to the bolt 210. The threaded coupling portion 530 includes a central sleeve 532 having a lower threaded section 534 and an upper pilot section 536. The upper pilot section 536 is blank, in that it does not include any features that couple with a bolt or screw. Instead, the pilot section 536 serves to align the bolt or screw with the threaded section 534 to reduce the chance of cross threading. The central sleeve 532 is held in position within the body 502 by axial braces 538 which extend between the central sleeve 532 and the body 502 in a radial direction. The central sleeve 532 may further be held in position by radial braces 540. The radial braces 540 comprise annular segments that extend from the central sleeve 532 to the body 502 and extend between and join adjacent axial braces 538.

A connector cap 400 is provided to cover the flange 220, 506 of each of the plug 500 and the bolt 210 once they are installed in a raft. The connector cap 400 assists to direct water away from the plug 500 and the bolt 210 by directing the water off the connector cap 400 and into drainage channels formed in a raft module 600. The drainage structures of the raft module 600 are described in more detail below.

The connector cap 400 includes an annular platform 402. The dimensions of the annular platform 402 are selected so that the annular platform 402 rests on the keying hub 228 of the bolt or, when the screw sleeve 500 and the plug 300 are engaged, the keying hub 508 of the sleeve screw and the rachet hub 342 of the plug 300.

The annular platform 402 extends about a central recess 404. The central recess 404 is adapted to receive the head of a bolt, for example, which may secure structures to the raft or may secure separate raft modules together as described in further detail below. The central recess 404 has a circular profile. Furthermore, the central recess 404 has a floor 406 spaced from the annular platform 402 to rest on the threaded coupling portions 250, 530 when the annular platform 402 rests on the hubs 228, 508. The floor 406 include an opening 428 for receiving a bolt or screw.

The connector cap 400 further includes an outer cover 408. The outer cover 408 is annular and is stepped down from the annular platform 402. The topside of the outer cover 408 includes grip members 410. These are designed to assist with under-foot traction with the raft modules. In this embodiment, the grip members 410 comprise radial ribs. However, it will be appreciated that other grip patterns may be utilised, for example raised circles, dots or polygons. An outer edge of the outer cover 408 is bevelled downwardly to form a rim. The downward curvature assists with run-off from the outer cover 408 into drainage channels. The underside of the outer cover 408 includes snap lugs 412 which are configured to connect with the bolt 210 and the plug 300. The snap lugs 412 have a generally L-shaped profile to form an interference fit with the lips 236 and 350 of the bolt 210 and the plug 300, respectively. This results in the outer cover 408 resting on the annular rim 224 of the bolt 210 when the connector cap 400 is coupled to the bolt 210 and on the annular rim 334 of the plug 300 when the connector cap 400 is coupled to the plug.

While the connector cover 400 is shown in this embodiment to include six snap lugs 412, this configuration is suitable for coupling the connector cap 400 with the plug 300 and the bolt 210 when the lips 236, 350 are discontinuous. In embodiments where the lips are continuous, the connector cap 400 may include four snap lugs 412. The number of snap lugs 412 included in the connector cap 400 may vary depending upon the configuration of the lips 236, 350. Accordingly, the number of snap lugs 412 may be three or more.

As shown in Figure 41, the connector cap 400 further includes a fill cap 416 which can be fitted within the central recess 404. The fill cap 416 includes a top wall 418 and a pair of skirt walls 420. In this embodiment, the top wall 418 is circular and the skirt walls 420 are arcuate. The skirt walls 420 extend from the perimeter of the top wall 418. The skirt walls 420 are spaced from each other by legs 422 which extend parallel with the skirt walls 420. The legs 422 extend from a location between skirt walls 420, but may, in an alternative embodiment, extend from the top wall 418. A free end of each leg 422 includes a bead 424. The bead 424 projects outwardly from each leg 422. The central recess 404 includes apertures 414 (Figures 41 and 42) which are adapted to receive respective beads 424. Accordingly, the fill cap 416 can be retained within the central recess 404 by inserting the fill cap 414 within the central recess 414 such that the beads 424 become seated in the apertures 414.

A raft module 600 is shown in Figures 48 to 55. The raft module 600 comprises a central core in the form of a body 602 from which extends on two adjacent sides an upper panel 604 and from which extends on two other adjacent sides a lower panel 606 which, in use, faces downwardly into a body of water. A top surface 608 of the raft module 600 comprises an upper surface of the body 602 in combination with the upper panel 604.

The top surface 608 further comprises a floor 642 of the lower panel 606. An underneath surface 610 of the raft module 600 comprises the underside of the body 602 in combination with an underside of the lower panel 606, plus a roof 664 on the underside of the upper panel 604.

The top surface 608 of the raft module 600 is shown in more detail in Figures 47 and 51. In particular, it can be seen that the raft module 600 includes an array of cavities in the form of connection apertures 644 formed in the upper and lower panels 604, 606 and anchor apertures 612 formed in the body 602.

The anchor aperture 612 is shown in Figure 54 extending from the top surface 608 to the underneath surface 610. The anchor aperture 612 opens at the top surface 608 in a seat, in the form of a step 614, recessed from the top surface 608. The anchor aperture 612 then transitions into a narrowed passage 616 which terminates at an inverted shoulder 618 which acts as a ledge against which the bead 320 of the plug 300 abuts in use. From there, the anchor aperture 612 transitions into a channel 620 that opens at the underneath surface 610 of the body 602.

The plug 300 is located in the anchor aperture 612 by forcing the body 302 downwardly into the passage 616 so that the legs 306 deform to an extent to pass the bead 320 through the passage 616 so the bead 320 engages the shoulder 618. The plug 300 is properly fitted when the rotation resisting projections of the raft module 600, in the form of protuberances 622 at the step 614, are located in the seats 336 at the perimeter of the flange 330 (Figure 50). The sleeve screw 500 is then screwed into the body 302 by engaging the external thread 504 of the sleeve screw 500 with the internal thread 304 of the plug 300. The formations 518 deflect under positive thread engagement, thereby allowing the pawls 520 to skip over the rachet formation 346 until the sleeve screw 500 is properly located when the sleeve screw 80 cannot be screwed in further. At this point, the pawls 520 of the sleeve screw 500 are engaged with the rachet formation 346 of the plug 300 and, therefore, the sleeve screw 500 is resisted from negative thread engagement (i.e. unscrewing). This arrangement of the plug 300 and the sleeve screw 500 allows structures to be secured to the body 602 with an appropriate fastener that engages the threaded section 534 of the threaded coupling portion 530. Such structures may include hand-rails and support frames for photovoltaic panels. As explained above, the fastener used to secure a structure to the sleeve screw 500 does not need to be a threaded fastener, but may instead be a snap-fit fastener or other type of fastener with the sleeve screw 500 adapted appropriately to co-operate with the selected fastener.

It will be appreciated that with the tubular body 502 of the sleeve screw 80 located in the plug 300 as shown in Figure 54, the tubular body 502 prevents the legs 306 from deflecting inwardly and releasing the plug 300 from the anchor aperture 612. With rotation of the screw sleeve 500 relative to the plug 300 resisted by the teeth pawls 520 and the rachet formation 346, wave and wind action is unlikely to cause the sleeve screw 500 to unscrew from the plug 300. It is anticipated that the structure will remain secured to the raft module 600.

The connection aperture 644 is the same as the anchor aperture 612 apart from: (a) being formed in the upper and lower panels 604, 606 only, (b) having a shorter channel 620 on account of the upper and lower panel 604, 606 having a reduced thickness compared to the body 602 and (c) omitting the protuberances 622 on the upper panel 604. Otherwise, the connection aperture 644 has the same step 614, passage 616 and shoulder 618 as the anchor aperture 612. It will be appreciated, that the connection apertures 644 in the upper panel 604 have the step 614 opening to the top surface 608 of the raft module 600 and in the lower panel 606 the connection apertures 644 are inverted with the step 614 opening to the underneath surface 610 of the raft module 600.

The raft module 600 shown in Figures 47, 48, 51 and 52 has a square array of 9 anchor apertures 612 in the body 602 and seven connection apertures 644 along each of the upper and lower panels 124, 126. However, the body 602 and the panels 604, 606 may include more or fewer apertures 612, 644. The number of apertures 612, 644 may vary with the size of the raft module 600. The apertures 612, 644 provide connection points between the top surface 608 and the underneath surface 610 so that the shape of the raft modules 120 won't vary significantly with variations in temperature. As shown in Figures 53 and 54, connecting adjacent raft modules 600 involves overlapping the upper panel 604 of one raft module 600 with a lower panel 606 of another raft module 600 and aligning the respective connection apertures 644. A plug 300 is located in the connection aperture 644 of the lower panel 606 and a bolt 210 is directed downwardly through the connection aperture 644 of the upper panel 604 so that the external thread 216 engages the internal thread 304 as shown in Figure 54. The bolt 210 is properly secured with the plug 300 when the plug 300 is pulled upwardly to be firmly seated in the step 614 with the protuberances 622 located in seats 336. Doing so causes the body 212 of the bolt 210 to be retained in the plug 300 so as to prevent the legs 306 from deflecting to release the plug 300 from the shoulder 618 of the connection aperture 644.

This connection process involves linking connection apertures 644 denoted A in Figure 21A with a first adjacent raft module 600, linking connection apertures 644 denoted B with a second adjacent raft module 600, linking connection apertures 644 denoted C with a third adjacent raft module 600, linking connection apertures 644 denoted D with a fourth adjacent raft module 600, linking connection aperture 644 denoted E with a fifth adjacent raft module 600 and linking connection aperture 644 denoted F with a sixth adjacent raft module 600. Accordingly, unless a raft module 600 is located on the perimeter of a raft, each raft module 600 will be linked to six adjacent raft modules 600.

Alternatively, some of the connection apertures 644 may be fitted with the bolt 210 to connect with an adjacent raft module 600 and the remaining connection apertures in the upper panel 604 may be fitted with a plug 300 and sleeve screw 500 to form an anchor point to which structures supported by the raft may be anchored and the remaining apertures 644 in the lower panel 606 may be left vacant. For example, the bolt 210 may be fitted to alternate connection apertures 644 in the upper panel 604 and plugs 300 with sleeve screws 500 may be fitted to the other connection apertures 644.

Additionally, plugs 300 may be fitted in connection apertures 644 of the lower panel 606 to co-operate with bolts 210 in connection apertures 644 of an adjacent raft module 600.

This interconnectivity between the raft modules 600 spreads forces through a raft formed of the modules 600 and thereby reduces stress localization (i.e. stress concentration) which can lead to connections failing and rafts breaking up under severe weather conditions. It is for this reason that a raft formed with the modules is preferably formed as a continuous array of modules, i.e. without gaps, such as gaps underneath photovoltaic panels. The lower panel has a floor which is bound on two sides by an outer wall. The elder wall includes a sloping wall and a return wall to the floor in the form of an abutment wall. The sloping wall and the abutment wall are raised above the level of the floor to form peaks between the connection apertures. The body of the raft module is linked to the floor by a series of surfaces. The surface is inclined relative to the floor and the body. The inclination of the surface improve strength of the raft module. The surfaces are separated by valleys which act as drainage chutes. The valleys connect with drainage channels form in the top surface of the body. The surfaces include at least one land each. Each land comprises a projection extending from the surface and have a level portion and an abutment portion.

The upper panel includes a roof formed on the underside of the upper panel. The upper panel is bound on two sides by an outer wall. Depending from the roof are a series of blocks. The blocks taper from the outer wall toward the body. The blocks are disposed on the side of the connection apertures. The body-side of the blocks has an interlock wall. When raft modules are brought together to form a raft, the upper panel on one raft module overlaps the lower panel on an adjacent raft module (as shown in Figures 53 and 54). In this configuration, the blocks overhanging the floor of the adjacent raft module and the interlock walls about the abutment walls of the peaks.

It can also be seen in figures 53 and 54 that the abutment portion of the lands about the blocks and that the upper panel projects from the body by distance less than the distance that the lower panel projects from the body. This results in a channel 682 being formed between adjacent raft modules. The base of the channel is collectively formed by the level portions of the lands. Additionally, the setback of the blocks from the outer wall results in the channel being wider in the portion above the lands than between the outer wall and the body of the adjacent raft module. The channel enables electrical cables associated with photovoltaic equipment to be stored below the level of the top surface. This means that the cables do not present a tripping hazard.

A further advantage of the channel is in load transfer. Specifically, floating rafts are typically anchored to land areas at the perimeter of the body of water. Often, anchor line are fixed to the raft at points and the loads from the anchor lines are distributed through the connectors between adjacent raft modules. This places a relatively high load on the connectors. The existence of channel enables anchor lines to extend through the raft, so the anchor load is maintained within the anchor line. The raft is connected to the anchor line at numerous locations so that any loads associated with such connection can be distributed throughout the raft more evenly.

The rounded corners of the raft modules results in a gap at an intersection between four raft modules. The gap may be closed over by a filler block which can be fixed to one of the raft modules at the intersection.

While raft formed in accordance with the raft modules 600 and 120 can be made in a single layer, stability of the raft may be improved by stacking modules about the perimeter of the raft in a double layer. An example of this is shown in Figure 55 where a long bolt 690 passes through the threaded coupling portion of the upper raft modules and engages the threaded coupling portion the bolt 210 in the lower of the stacked raft modules. The lower raft modules in the stack may be filled with water. The lower raft modules may include holes that allow water to fill an interior volume of the raft modules. In this configuration, the upper stacked raft modules remain intact and buoyant. The ballast effect provided by the lower, water-field, raft modules serves to stabilise the perimeter of the raft from lifting due to the combined effect of wave and wind action.

Those skilled in the art of the present invention will appreciate that many variations and modifications may be made to the preferred embodiment without departing from the spirit and scope of the present invention.

In the claims which follow, and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word "comprise" and 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 apparatus and method as disclosed herein.

In the foregoing description of preferred embodiments, specific terminology has been resorted to for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar technical purpose. Terms such as "front" and "rear", "inner" and "outer", "above", "below", "upper" and "lower" and the like are used as words of convenience to provide reference points and are not to be construed as limiting terms. For example, the fixing member may be deployed in cavities in the upper surface and in the lower surface of a raft module in respective different orientations. However, the function of the fixing member in each orientation remains the same, but it is described in the orientation with the fixing member in the upper surface of the raft module for simplicity and convenience.

Furthermore, invention has been described in connection with what are presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. Also, the various embodiments described above may be implemented in conjunction with other embodiments, for example, aspects of one embodiment may be combined with aspects of another embodiment to realize yet other embodiments. Further, each independent feature or component of any given assembly may constitute an additional embodiment.