[0001] The present invention relates broadly to materials handling and more specifically to storing and dispensing particulate materials.

[0002] The invention has been developed primarily for use in storing grain and/or animal feed, and will be described herein with reference to this application. However, the invention is not limited to these applications and is suitable for use with a broad range of granular or particulate material.

[0003] The following discussion of the background to the invention is intended to facilitate an understanding of the invention. However, the discussion is not an acknowledgement or admission that any of the material referred to was published, known or part of the common general knowledge in Australia or any other country as at the priority date of any one of the claims of this specification.

Background of Invention

[0004] Traditionally with temporary grain or hay storage, a barn or shed is provided with a concrete floor upon which the grain or hay is deposited in heaps. The provision of a storage barn or shed is expensive to construct and relocate. Farmers may revert to heaping the grain or hay directly on the ground. In this case the heaped grain may be covered with a tarpaulin, but this manner of temporary storage is generally inadequate because of exposure to moisture and susceptible to ground- based attacks from rats, mice, mould and contaminants, and other foreign matter.

[0005] Alternatively, it is common to store granular products such as grain in silos. Grain silos are generally cylindrical in shape having a conical or frusto-conical base and/or roof. The cylindrical body is fabricated from sheet steel in a series of ring segments secured upon one another via multiple fasteners such as tek screws (i.e. a self-tapping fastener). The base and roof are also fabricated from sheet steel which is cut and folded then fastened in the required configuration. The silos are typically constructed in a metal fabrication factory and then transported to site for on-farm grain storage. The cylindrical metal silo is relatively expensive to manufacture, difficult to transport, and involves high ongoing maintenance costs.

[0006] To address these issues, the applicant has developed a modular silo described in WO 2014/201497 A1 . This silo is formed from one or more transportable silo modules that are constructed onsite. Similarly, the silo modules may be permanently installed, or disassembled and moved to another site without affecting the operation of any remaining silo modules. Each silo module has an elongate channel with an auger assembly extending along the bottom. The auger assembly is a helical auger that rotates to push the grain to an outlet at one of the longitudinal ends.

[0007] Placing the silo modules side by side and/or, end to end, allows a single large pile of granular product or other particulate material, to be supported off the ground in the adjacent channels beneath. The auger assemblies can be run simultaneously or individually to dispense the grain as required.

[0008] The weight of the particulate material can be significant. As such, the structure of the channels and their supporting structures need to be robust enough to prevent excessive deformation. This requires the sheet material forming the sides of the channel to have a certain thickness for the necessary strength and rigidity. This is particularly so for relatively long channels where the spacing between the underlying supporting structure is also long. However, increasing the structural strength and rigidity of the silo modules increases the weight which in turn increases the production costs and makes the silo modules less convenient to transport and assemble.

[0009] The present invention seeks to provide a silo module forming part of a silo and a method of constructing the silo, which will overcome or substantially ameliorate at least some of the deficiencies of the prior art, or to at least provide an alternative.

[0010] Any reference herein to a patent document or other matter which is given as prior art is not to be taken as an admission that that document or matter was known or that the information it contains was part of the common general knowledge as at the priority date of any of the claims. [0011] Throughout the description and claims of the specification, the word "comprise" and variations of the word, such as "comprising" and "comprises", is not intended to exclude other additives, components, integers or steps.

Summary of Invention

[0012] According to a first aspect, the present invention provides a silo module for a silo, the silo module comprising: a base structure for locating the silo module on a selected area of ground; one or more channel sections for being supported on the base structure such that each of the channel sections have an open top to receive particulate material therein; a rotatable auger in each of the channel sections to drive the particulate material towards a longitudinal end of the channel section; and, a mounting structure at the open top of each of the channel sections for engagement with the base structure; wherein during use, each of the channel sections are suspended by the mounting structure.

[0013] Ongoing development of the silo has found that suspending the channel sections from their open tops, instead of cradling the underside of each channel, allows the channels to be formed from thinner sheet material without excessive deformation of the channel sides. The thinner channel sections are more easily transported and assembled on site. Similarly, material costs are reduced.

[0014] Preferably, the or each channel section has a longitudinally extending trench in the bottom of the channel to house the auger.

[0015] Optionally, the or each channel section is generally V-shaped in cross section with inclined channel walls extending from each side of the trench at the bottom of the channel, such that in use the channel walls are inclined at an angle steeper than the angle of repose for the particulate material to be stored. [0016] Preferably the base structure provides elongate support rails for supporting the or each channel section along its longitudinal sides.

[0017] Preferably, the or each channel section has an auger cover for mounting above the auger such that in use the auger cover bears the weight of the particulate material above, while also allowing the particulate material to feed to the auger from one or both sides of the channel section.

[0018] Preferably, the or each channel section has a fumigation conduit for connection to a supply of fumigant, the fumigation conduit configured for supplying the fumigant into the particulate matter held by the channel section. Optionally, the fumigation conduit extends adjacent to the auger, the fumigation conduit having one or more fumigant outlet apertures. Preferably, the fumigation conduit longitudinally extends above the auger and beneath the auger cover. In a particularly preferred form, the auger cover has a transverse cross section that is an inverted V-shape. Preferably, the fumigation conduit extends along the underside of the peak of the inverted V-shaped cover.

[0019] Preferably, the silo module further comprises a mounting configuration for detachably securing a flexible covering over the particulate material held in the or each channel section. Optionally, the mounting configuration is a rope track groove and the flexible sheet covering is a tarpaulin with a peripheral rope at the edges for retention in the rope track groove.

[0020] Preferably, the silo module further comprises at least one grating on one or more of the channels to support the weight of a person during maintenance operations to areas intermediate the channel ends. The grating has apertures large enough to allow the particulate material to flow freely into the or each channel section.

[0021] According to a second aspect, the present invention provides a silo comprising a plurality of the silo modules defined above, wherein the silo modules abut each other along the longitudinal sides of the respective channel sections.

[0022] Optionally, two or more of the silo modules are arranged side by side such that the augers are parallel and the longitudinal ends of the channel sections are aligned with each other. Optionally, two or more of the silo modules are arranged end to end such that the augers are aligned and drive the particulate material in opposing directions to opposite sides of the silo.

[0023] Preferably, each of the channel sections is formed from sheet material with peripheral configurations for engagement with the peripheral configurations of adjacent channel sections.

[0024] According to a further aspect, the present invention provides a method of assembling a silo, the method comprising: positioning a base structure on the ground at a selected location; supporting one or more elongate channel sections on the base structure such that the channel sections open upwardly for receiving particulate material; installing an auger in the or each channel section for drawing the particulate material to a longitudinal end of the channel section; and, engaging the channel sections with the base structure using mounting structures along an upper edge of the channel walls such that the channel sections are suspended by the mounting structures.

[0025] Preferably at least two of the channel sections, detachably connect to each other along the upper edge of adjacent channel walls via the respective mounting structures. The mounting structure may be an integrally formed mounting flange extending about the periphery of their upper, open top. Preferably, the mounting flanges of two adjacent channel sections interconnect such that the channel sections rest upon parts of the base structure extending beneath the flanges.

[0026] Preferably, the channel sections are formed from sheet metal. In a further preferred form, the sheet metal is stainless steel sheet.

[0027] Preferably, the method further comprises the step of installing an auger cover above the auger in each channel section such that, in use, the auger cover bears the weight of the particulate material above while allowing the particulate material to feed into the auger from one or both sides of the channel section.

[0028] Preferably, each of the channel sections have a longitudinally extending trench formed in the base of the channel for housing the auger.

[0029] Preferably, the method further comprises installing a fumigation conduit into each of the channel sections for connection to a fumigant supply and delivery of fumigant to the particulate material held in the channel section.

[0030] Preferably, the method further comprises installing a grating over the open top of the channel sections, the grating configured to support a person and allow the particulate material to flow freely into the or each channel section.

[0031] Using the principle of "hoop tension", the applicant has developed a silo structure constructed with an efficient use of materials and relatively low production and installation costs. With the channel sections suspended from the support structure at their upper edges, the channel sides support the weight of the particulate material through predominately tensile forces distributed through the plane sheet metal. This takes advantage of the relatively high tensile strength of the metal while avoiding large deflections in the structure from bending loads on the channels caused by supporting them at spaced locations along the channel underside. From this, the silo design is readily suited to:

1 . a permanently installed silo structure;

2. the ability for long term storage of granular material;

3. an exponential increase in the storage capacity with the addition of further silo modules;

4. conversely, an exponential decrease in the costs per ton of storage;

5. the ability to store different granular products simultaneously without loss of storage capacity; 6. no cross-contamination between different granular products being simultaneously stored;

7. readily able to fumigate stored granular products;

8. the ability to store grain elevated from the ground to keep the granular product relatively dry;

9. conveniently low and open structure for purposes repairs and maintenance;

10. the modular silo structures are reusable and recyclable through various different applications;

1 1 . the structure is conveniently disassembled for relocation elsewhere.

Brief Description of Drawings

[0032] Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

[0033] Figure 1 is a perspective view of an embodiment of two silo modules of a series of silo modules arranged in a side-by-side relationship to provide a silo according to the present invention;

[0034] Figure 2 is an enlarged and partially exploded perspective view of Inset A shown in Figure 1 ;

[0035] Figure 3 is a side elevational view of another embodiment of a series of silo modules arranged in an end-by-end relationship to provide a silo according to the present invention;

[0036] Figure 4 is a side elevational view of one of the silo modules of the embodiment of the silo of Figures 1 and 2;

[0037] Figure 5 is an end elevational view of a series of three silo modules in side-by-side relationship to provide a silo according to the present invention; [0038] Figure 6 is an exploded perspective view of the two silo modules of the embodiment of the silo of Figures 1 and 2;

[0039] Figure 7 is an enlarged and partially exploded view of Section 7-7 shown in Figure 1 ;

[0040] Figure 8 is an enlarged and partially exploded view of Section 8-8 shown in Figure 1 ;

[0041] Figure 9 is a partially cut away front elevation of a cargo vessel filled with a particulate handling assembly according to a related aspect of the present invention;

[0042] Figure 10 is a partially cut away perspective view of the cargo vessel shown in Figure 9;

[0043] Figure 11 is a schematic section view of a supporting pad for a pile of particulate material, the pad being filled with a particulate handling assembly according to another related aspect of the invention.

[0044] Figure 12 is an enlarged and exploded partial perspective of the central join in the supporting pad of Figure 1 1 ;

[0045] Figure 13 is an enlarged partial section view of the join shown in Figure 12;

[0046] Figure 14 shows a partial perspective view of a block used at the connection between the lateral sides of two channel sections according to the present invention;

[0047] Figure 15 is a schematic section view of the block shown in Figure 14 used to join two adjacent channel sections;

[0048] Figures 16A, 16B and 16C are front, side and top views respectively of grain supported on a modular silo of 12 modules in side-by-side relationship.

[0049] Figures 17A and 17B are front and top views of grain supported on a modular silo of 24 silo modules in two abutting rows of 12 in side-by-side relationship; and [0050] Figure 18 is a top view of grain supported on a modular silo of 48 silo modules in abutting rows of 24 in side-by-side relationship,

Detailed Description

[0051] Modular Silo

[0052] Referring to Figures 1 to 8, a silo 10 is shown with two silo modules 12A and 12B however, the number of silo modules forming the modular silo is arbitrary and simply determined by the required storage capacity. Each silo module 12A and 12B has a respective channel section 14A and 14B mounted on a base structure 18. Again, the number of channel sections forming a single silo module is arbitrary and the base structure 18 may be a common base structure shared by more than one of the silo modules 12A and 12B or an individual base structure for each silo module respectively.

[0053] The base structure 18 shown in Figure 1 provides a series of elevated rectangular frames in which the channel sections 14A and 14B are mounted. A pair of lateral bottom rails 26 are spaced apart by a series of longitudinal bottom rails 34 extending upwards from the lateral bottom rails 36 are vertical struts 32 which support the back lateral top rail 24, front lateral top rail 26 and the longitudinal top rails 38 extending therebetween.

[0054] Terms such as 'front', 'back', 'top' and 'bottom' are used in the context of the embodiments shown in the Figures where the outlet end of the silo modules 12A and 12B are considered the front while the opposing longitudinal end are considered to be at the back of the silo. The skilled worker in this field will readily appreciate that terminology used to denote the orientation of particular silo modules is not used in an absolute sense. Silos 10 with silo modules arranged 'back to back' will have the front side of adjacent silo modules face opposite directions.

[0055] The channel sections 14A and 14B are sheet metal channels with inclined side walls 20A and 20B leading to an auger trench 46 formed in the bottom of each channel. First and second augers 16A and 16B extend along the auger trench 46 for the first and second channels 14A and 14B respectively. The first and second augers 16A and 16B drive the particulate matter in each channel section towards the first and second channel outlets 30A and 30B respectively. Directly above the first and second channel outlets 30A, 30B is a fumigation conduit 50 extending from the first and second channel front walls 28A and 28B. The fumigation conduit extends into each channel respectively to deliver a supply of fumigant to the underside of an auger cover 52 extending above each of the augers 16A and 16B. A flow of fumigant beneath the inverted V-shaped auger covers 52 effectively disperses across the particulate matter such as grain as it is drawn towards the outlet 30A and 30B.

[0056] The auger cover 52 is spaced from the side walls 20A and 20B of the channel sections 14A and 14B such that grain can enter the auger trench 46 but the weight of the grain stored above the augers is supported by the auger covers 52. In this way, the operation of the augers 16A and 16B is relatively unaffected by the amount of grain held by the silo.

[0057] Within each of the channel sections 14A and 14B are metal gratings 48 which support the weight of a worker attending to repairs and maintenance along the length of each silo module 12A and 12B.

[0058] As best shown in Figure 2, the channel sections 14A and 14B have a channel mounting flange 40 extending about the open top of each channel. The channel mounting flange 40 allows each channel section 14A and 14B to be suspended beneath the rectangular frame provided by the front lateral top rail 26, the back lateral top rail 24 and the two spaced apart longitudinal top rails 38. Suspending the channel sections from their open tops ensures that the sheet metal sides and ends are in tension rather than compression. As discussed above, if the channel sections 14A and 14B were supported from below they would be prone to deformation and buckling side walls from the weight of the particulate material. With the channel walls remaining in tension under the load of the stored grain, the thickness of the sheet metal is reduced thereby lowering material costs for the silo 10. Furthermore, lighter channel sections 14A and 14B are more easily transported and assembled in a remote location.

[0059] The channel mounting flanges may be held in place using threaded fasteners or simply keying into a complementary formation (not shown) in the top surface of the base structure 18. This will shorten the assembly and disassembly times for the silo 10.

[0060] The silo 10 may also be fitted with tarpaulin retention grooves 44 using the triangular mounting block 42. Covering the grain with a tarpaulin provides protection from the elements as well as infestation.

[0061] Figures 3, 4 and 5 illustrate various configurations the silo modules 12A, 12B and 12C can adopt. In Figure 3, the silo modules 12A, 12B and 12C are longitudinally aligned end to end such that they each share a common auger trench 46 and common auger (not shown) leading to a single channel outlet 30A. In this configuration, the sheet metal channel sections are relatively short which may be more convenient to transport and less difficult to assemble thereby allowing the silo to be constructed by a single person at a remote location.

[0062] In Figure 4, the single silo module 12A is a much longer channel which requires longer sheet metal sections that are heavier and more difficult during construction. However, a single channel has a larger capacity than a series of individual channels as shown in Figure 3.

[0063] Figure 5 illustrates a side view for either Figure 3 or Figure 4 in which a series of long channels such as shown in Figure 4, are arranged side by side, or a series of the shorter channels as shown in Figure 3 are arranged side-by-side in rows.

[0064] Figures 7 and 8 show alternative arrangements for mounting the channel sections to the base structure 18. Figure 7 shows a partial section view through the silo 10 at the location indicated by shading 7-7 in Figure 1 . Figure 8 shows Section 8- 8 indicated by the shaded area in Figure 1 .

[0065] The channel side walls 20A and 20B are sheet metal with the channel mounting flange 40 integrally formed at the upper edge. The top edge of the channel is bent under to provide a lip formation with a right angle triangle section. The base of the triangle rests on the upper surface of the longitudinal top rails 38 of the base structure 18 (see Figure 1 ). The vertical side of the triangle has fastener holes 60 that align with the fastener holes in the triangular lip formation of the adjacent channel wall. Sandwiched between the two vertical sections of the triangle is the mounting fin for the tarpaulin retention groove 44. The two adjacent channel side walls 20A and 20B are clamped together via fasteners such as bolt 54 and hex nut 56 through the fastener holes 60. The inclined sides of the triangular formation have a series of access apertures 58 aligned with the fastener holes 60 for attaching and removing the fasteners 54 and 56.

[0066] The channel side walls 20A and 20B are inclined at an angle steeper than the angle of repose for the granular material to be held by the silo. In this way, the granular material will feed under gravity to the auger trench 46 at the bottom of each channel section. At the front and rear ends of the channel section, there may not be any adjacent channel section (depending on the channel configuration selected) for attachment to the triangular upper lip. As shown in Figure 8, the first channel outlet end wall 28A attaches to a complementary mounting bracket 62 rather than an adjacent channel section. The mounting bracket 62 has a complementary triangular lip to refine the necessary mounting flange 40 and fastener holes 60 with the required access apertures 58 for the fasteners 54 and 60. However, the mounting bracket 62 simply wraps partially around the front top rail 26 to securely position the triangular lip and firmly hold the front longitudinal end wall 28A of the channel section. Of course the mounting bracket may also be used on the longitudinal top rails 38 to secure the outer sides of the outer most channel sections.

[0067] Figures 14 and 15 show an alternative technique for anchoring the channel walls to the top rails 38 of the base structure. As shown in Figure 15, this technique may be suited to silo installations in which two separate base structures 18 (see Figure 1 ) are positioned side by side. The outermost top rails 38 abut each other and the channel side walls 20A and 20B secure to a module connection block 94, rather than two separate mounting brackets 62 as shown in Figure 8. The module connection block 94 may be any convenient material such as wood or suitable polymer. It also provides a series of fastener holes 60 to align with those within the triangular lips of the adjacent channel side walls 20A and 20B.

[0068] Referring to Figures 16A, 16B and 16C the front side and plane views of a silo 10 are shown holding a quantity of grain 96. In the embodiments shown, the base structure 18 supports twelve adjacent channel sections 12A to 12L each with respective outlets 30A to 30L facing one end. The applicant has found a silo of this type holds approximately 500 tonnes of grain 96 and therefore refers to this configuration as a 500 tonne unit 98. While the 500 tonnes is distributed across the twelve modules 12A to 12L, the applicant has found that suspending each of the channel sections 14A to 14L from their upper edges as discussed above results in far less sidewall deformation, therefore allowing thinner sheet metal material to be used. Workers in this field will understand the benefits of using channel sections of thinner sheet metal from both a material cost point of view and the ease of transport and assembly.

[0069] Referring to Figures 17A and 17B, two 500 tonne units 98 are arranged back to back such that their respective outlets 30A to 30L face in opposite directions. In this case, the entire silo 10 has a capacity greater than twice the 500 tonne of grain 96 held by an individual 500 tonne unit 98. As best shown in Figure 17A, the grain 96 will pile onto both of the 500 tonne units 98 in accordance with its particular angle of repose to form a single grain heap. In this configuration, the extra grain storage capacity 100 allows two adjacent 500 tonne units to store more than 1000 tonnes of grain 96. Figure 18 is a plan view of four 500 tonne units 98 in which the two back to back units of Figure 17 are positioned adjacent to additional back to back units 98. In this case, the extra storage capacity 100 increases significantly and a total capacity of four 500 tonne units 98 is in excess of 3600 tonnes.

[0070] It will be appreciated that the storage capacity continues to increase with the addition of further units abutting the existing units. This provides the ability to use temporary silos with variable capacity to suit different grain storage requirements. For example, in high yield years additional grain may be stored on farm prior to transport to the mill. Similarly, in times of drought, feed for livestock may be stored in a modular silo for extended periods of time without spoilage. Individually operable augers 16 will allow the grain to be dispensed in a controlled manner.

[0071] Method [0072] Constructing a silo 10 such as that described in the preceding paragraphs, generally involves assembling each of a predetermined number of silo modules 12A to 12X in-situ. Typically, the main steps involved are as follows:

1 . Erecting a base structure 18 preferably having a rectangular framework with elevated front 26, back 24 and longitudinal 38 top rails, at the desired location.;

2. Mounting a channel section 14A upon the base structure 18 wherein the channel sections 14A-14X are formed from sheet metal components. Preferably, these are prefabricated and supplied in ready to assemble form.

3. Augers 16A to 16X are positioned in the auger trenches 36 for each of the channel sections respectively. Each of the augers will be configured at one or more points for axial rotation to drive the grain towards the outlet end of the channel. The augers may be configured to be driven collectively or individually via suitable drive trains and clutch arrangements. The auger drive trains (not shown), are configured for attachment to any suitable powered input shaft and preferably provides a gearbox for controlling the auger speed and torque.

4. The outer periphery of the silo 10 has a tarpaulin mounting groove 44 extending about the open top. Once grain or other particulate material has been loaded into the silo, a flexible covering such as a tarpaulin encloses the grain to protect against the elements and infestation.

[0073] The modular silo 10 is constructed by interconnecting the required number of silo modules in a side-by-side and/or end-to-end relationship. The silo 10 may have any number of silo modules 12A to 12X to suit the required capacity. The silo modules can adopt any configuration in which the channel section outlets are on an external periphery.

[0074] Now that a preferred embodiment of the invention has been described, it will be apparent to those skilled in the art that the silo module and entire silo have the following advantages over the admitted prior art:

1 . The modular construction of the silo lends itself to construction in-situ; 2. The modular nature also lends itself to scaling up or down depending on the application and storage requirements with relative ease;

3. The silo modules are configured for ease of transportation in either a pre- constructed or flat-pack form;

4. The silo can be configured based largely on the number of silo modules to accommodate or contain relatively large volumes of particulate matter.

[0075] Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. For example, the silo modules need not be limited to the sizes and materials described. The silo modules are designed to contain practically any granular products or particulate material including wheat and other grains, superphosphate and other granular fertilizers, particulate matter including minerals and ores in the mining and resources sector, and particulate matter including stock feed pellets and milk powder in the food industry. All such variations and modifications are to be considered within the scope of the present invention the nature of which is to be determined by the skilled worker from the description in the context of the common general knowledge in this field.

[0076] Figures 9 and 10 show a related aspect of the invention in which the granular material drive system is installed in the hold of a cargo vessel 64. The floor of the cargo hold is a V-shaped sloping surface 66 with a central auger 68 extending along the lowest point of the 'V. Each inclined side of the V-shaped floor 66 has a corrugated or V-shaped profile extending perpendicular to the central drive auger 68. The incline of these corrugations is greater than the angle of repose for the particulate material. These formations may also be engaged with a vibration drive or pressurised air to force any residual particulate material towards the central drive auger 68.

[0077] The cargo hold 70 may be separated by a fore bulkhead 72 and aft bulkhead 74. A unitary central auger 68 may extend through the bulkheads 72 and 74 or separate individual augers may extend between each of the bulkheads. [0078] This system allows the hold 70 to be filled with grain behind the aft (?) bulkhead and simultaneously distributed forwards to the forward bulkhead. Similarly, the particulate cargo can be driven to the fore or aft end of the vessel for unloading in a single operation rather than drawing the grain out of the hold 70 at several different locations.

[0079] Figures 1 1 , 12 and 13 show a further related aspect of the present invention. In this form, the auger drives are positioned along a V-shaped surface profile in the top of a cement slab. In this aspect of the invention, coal or some other type of particulate mineral 76 is loaded onto the support pad 92. The support pad 92 is a wide inverted V-shape with a first sloping corrugated support 78 rising to meet a second sloping corrugated support 80 at the support pad joint 84.

[0080] As best shown in Figure 13, the support pad joint 84 has a first complementary joint formation 88 for inter engagement with the second complimentary joint formation 90 such that the first sloping corrugated support 78 and the second sloping corrugated support 80 extend away from each other at the desired incline. At the bottom of each corrugation are individual augers 82. The augers 82 are configured to drive the coal 76 off the support pad 92 and onto conveyers 86 for transport or further processing.

[0081] Definitions

[0082] Whenever a range is given in the specification, for example, a temperature range, a time range, or concentration range, all intermediate ranges and subranges, as well as all individual values included in the ranges given are intended to be included in the disclosure. It will be understood that any subranges or individual values in a range or subrange that are included in the description herein can be excluded from the claims herein.

[0083] All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and/or ordinary meanings of the defined terms. Throughout this application, the term "about' is used to indicate that a value includes the inherent variation of error for the device, the method being employed to determine the value, or the variation that exists among the study subjects.

[0084] The indefinite articles "a" and "an," as used herein in the specification, unless clearly indicated to the contrary, should be understood to mean "at least one."

[0085] The phrase "and/or," as used herein in the specification, should be understood to mean "either or both" of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with "and/or" should be construed in the same fashion, i.e., "one or more" of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the "and/or" clause, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, a reference to "A and/or B", when used in conjunction with open-ended language such as "comprising" can refer, in one embodiment, to A only (optionally including elements other than B); in another embodiment, to B only (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.

[0086] Spatially relative terms, such as "inner," "outer," "beneath," "below," "lower," "above," "upper," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the Figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the Figures.

[0087] Where the terms "comprise", "comprises", "comprised" or "comprising" are used in this specification (including the claims) they are to be interpreted as specifying the presence of the stated features, integers, steps or components, but not precluding the presence of one or more other features, integers, steps or components, or group thereof.