Abstract:
An air-gap device integrated within a faucet base of a faucet fixture for use with a dishwashing device is disposable on a counter surface and includes: a base forming flow channels adapted to provide a fluid-tight seal at the surface; a fixed block wall extending from the base, the fixed block wall separating a first pair of flow channels from a second pair of flow channels and providing a fluid-tight seal for the first pair of the flow channels; and a removable block cover selectively attachable to the fixed block wall to fluidicly couple the second pair of flow channels, the block cover further forming an air-gap channel in fluidic communication with ambient. Modular design permits removal of the faucet and valve portion to access the air-gap device for maintenance, without the need to disconnect any fluid supply or waste lines.

Description:
FIELD OF THE INVENTION 
     The present invention relates to an air-gap device and, more specifically, an air-gap device that may be integrated into a faucet for use with a dishwashing device. 
     BACKGROUND OF THE INVENTION 
     Conventionally, air-gap devices may be installed in plumbing waste lines as a safety device to prevent drain water from entering a clean water system. Typically, the air-gap device is installed upstream of a drain to prevent back up of drain water into a clean water system or conduit. As the name suggests, and as shown in  FIGS. 1A and 1B , conventional air-gap devices  10  include an open space at ambient conditions (the “air-gap”  15 ) between an outlet  11  of a first fluid conduit  12  and an inlet  13  of a second fluid conduit  14 . As a result, if the unpressurized drain, or second fluid, line  14  were to become stopped or clogged (e.g., by small pieces of food), the air-gap device  10  would leak incoming water from the pressurized first fluid conduit  12  via the air-gap  15  into a nearby sink  19  or other water reservoir. 
     Air-gaps have been incorporated or integrated into various faucets or spouts connected to under-sink appliances, e.g., instant hot water heaters and reverse osmosis (RO) units. In these applications, the air-gap prevents waste fluid from being forced or siphoned back into the storage tank or reservoir of the under sink appliance. 
     Many U.S. states and cities, such as California, require plumbing of new homes to include an air-gap device  10  between a drain hose  17  of a dishwashing device, such as a dishwasher  18 , and its drain line  16 . This requires providing, in a kitchen counter top  22 , a first opening  24  for receiving a conventional hot and cold water faucet  20  and another opening  26  for receiving the air-gap device  10 . Advantageously, installing an air-gap device  10  above the counter top  22  prevents a clogged drain or sink  19  backup directing contaminated water back into the dishwasher  18 . This arrangement has several disadvantages. 
     First, it requires providing in the counter top  22 , e.g., by coring, by drilling, and the like, an additional opening  26  at a precise location about the opening  28  for the sink  19 . Second, typically, the air-gap device  10  cannot be disposed immediately adjacent to the sink  19 , hence, the air-gap device  10  is located a short distance  29  from the sink  19 , which means that leaking or weeping drain water from the air-gap device  10  must travel over the counter top  22  for some distance  29  before it enters the sink  19 , if it drains into the sink  19  at all. Finally, the air-gap device  10  can be noisy, unsightly, and a nuisance when trying to clean around the sink  19 . 
     BRIEF SUMMARY OF THE INVENTION 
     Accordingly, it is desirable to provide an air-gap device—especially an air-gap device for a dishwasher—that is structured and arranged to be installed within a faucet, to minimize these above and other disadvantages. 
     In a first aspect, the present invention provides a modular air-gap device that is disposable on a surface within a faucet base housing of a faucet fixture. In some embodiments, the air-gap device includes a base forming flow channels; a fixed block wall extending from the base, the fixed block wall separating a first pair of flow channels from a second pair of flow channels and providing a fluid-tight seal for the first pair of the flow channels; and a removable block cover selectively attachable to the fixed block wall to couple, e.g., fluidicly, the second pair of flow channels, the cover forming an air-gap channel in fluidic communication with ambient to avoid spatter. In some implementations, the first pair of flow channels is structured and arranged to connect to a cold water supply line and a hot water supply line and/or the second pair of flow channels is structured and arranged to connect to a, e.g., pressurized, waste water line and a drain line. In some variations, the drain line has an inner diameter that is greater than an inner diameter of the waste water line. 
     In some implementations, the air-gap channel may be substantially U-shaped, such that the U-shaped air-gap channel includes a pair of legs of unequal length with a longer leg of the U-shaped air-gap channel directing fluid flow to a drain line and a shorter leg of the U-shaped air-gap channel receiving flow from a waste water line. 
     In some implementations, the removable block cover may form an aperture, which may be formed proximate a drain line, to provide fluidic communication between the second pair of flow channels and ambient. In some variations, the air-gap device also may include conduits extending from the base and in fluid communication with a corresponding flow channel. 
     In a second aspect, the present invention provides a faucet having an air-gap feature. In some embodiments, the faucet includes a fluid-carrying spigot having an inlet and an outlet for communicating a fluid therethrough; a valve in fluidic communication with the inlet of the spigot for selectively controlling a flow rate and/or a temperature of the fluid; a faucet base housing having an overflow discharge outlet formed therethrough; and an air-gap device disposable on a surface and within the faucet base housing. In some implementations, the air-gap device includes a base forming flow channels; a fixed block wall extending from the base, the fixed block wall separating a first pair of flow channels from a second pair of flow channels and providing a fluid-tight seal for the first pair of the flow channels; a removable block cover selectively attachable to the fixed block wall to fluidicly couple the second pair of flow channels; and a crown portion extending from the fixed block wall. In some implementations, the removable block cover may form an aperture, which may be formed proximate a drain line. In some variations, the first pair of flow channels may be structured and arranged to connect to a cold water supply line and a hot water supply line and/or the second pair of flow channels may be structured and arranged to connect to a waste water line and a drain line. The drain line may also have an inner diameter that is greater than an inner diameter of the waste water line. In some variations, the faucet may include conduits in fluid communication with a corresponding flow channel and extending from the air-gap base. 
     In some variations, the block cover forms an air-gap channel in fluidic communication with ambient and the air-gap flow channel may be in fluidic communication with the overflow discharge outlet in the faucet base. 
     In some implementations, the faucet base housing may be removably coupled to the crown portion with a fastening device. Moreover, the faucet may include a first seal and a second seal to direct overflow from the air-gap flow channel to the overflow discharge outlet in the faucet base housing. For example, the first seal may be removably attached to the air-gap base and/or the second seal may be removably attached to the crown portion. 
     In some implementations, the air-gap channel may be substantially U-shaped such that the U-shaped air-gap channel may include a pair of legs of unequal length with a longer leg of the U-shaped air-gap channel directing fluid flow to a drain line and a shorter leg of the U-shaped air-gap channel receiving flow from a waste water line. 
     In a third aspect, a method is described for accessing an obstructed fluid flow channel within a faucet having a faucet base housing and an air-gap device including a base forming a plurality of flow channels; a fixed block wall extending from the base, the fixed block wall separating a first pair of flow channels from a second pair of flow channels and providing a fluid-tight seal for the first pair of the flow channels; and a removable block cover selectively attachable to the fixed block wall to fluidicly couple the second pair of flow channels, the cover forming an air-gap channel in fluidic communication with ambient. In some embodiments, the method includes removing the faucet base housing and removing the block cover of the air-gap device. In some variations, removing the block cover includes removing securing devices that secure the block cover to the fixed block wall. 
     In some implementations removing the faucet base housing and the removable block cover may be both performed above a sink counter level and/or removing the faucet base housing and the block cover may be performed without detaching any fluid lines from the faucet. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. In the following description, various embodiments of the present invention are described with reference to the following drawings, in which: 
         FIG. 1A  shows a conventional arrangement of a sink faucet and a separate air-gap device for use with a dishwashing device in accordance with the prior art; 
         FIG. 1B  shows an exemplary embodiment of an air-gap device for use with a dishwashing device in accordance with the prior art; 
         FIG. 2A  shows a side view of an illustrative embodiment of a faucet integrated with an air-gap device in accordance with the present invention; 
         FIG. 2B  shows an exploded perspective view of an illustrative embodiment of a faucet integrated with an air-gap device in accordance with the present invention; 
         FIG. 2C  shows a rear perspective, partially disassembled view of an illustrative embodiment of a faucet integrated with an air-gap device with a faucet base housing and a removable block access cover removed, in accordance with the present invention; 
         FIG. 3  shows the air-gap device from  FIG. 2C  with the removable block access cover removed from the air-gap device in accordance with some embodiments of the present invention; 
         FIGS. 4A and 4B  show cross-sectional views of an illustrative embodiment of an assembled faucet integrated with an air-gap device in accordance with the present invention; and 
         FIG. 5  shows a flow chart of a method of clearing an obstruction, clog, and/or blockage from the air-gap device in accordance with some embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     An embodiment of a combined faucet and air-gap device for an appliance, e.g., dishwasher, reverse osmosis (RO) unit, instant hot water unit, and the like, are described with reference to  FIGS. 2A through 2C . For ease of description, the kitchen appliance will be a dishwasher  18  ( FIG. 1A ). However, those of ordinary skill in the art can appreciate the wide variety of appliances that may be fluidly coupled to an air-gap device. 
     In some embodiments, the faucet/air-gap device  100  (hereinafter the “device”) may include an upper faucet assembly  30  and an air-gap portion  60  to which a plurality of fluid conduit lines  16 ,  17 ,  21 , and  23  is fluidicly coupled or connected. For example, in addition to having a hot water conduit  21  and a cold water conduit  23  (hereinafter “lines”) for fluidicly coupling or connecting to a hot water source and a cold water source, respectively, an inflow conduit  17  and an output or drain conduit  16  may be fluidicly coupled or connected to the device  100 . More specifically, the inflow conduit  17 , which may be fluidicly coupled to a pressurized drain line of a dishwasher  18 , and an output or drain conduit  16 , which may be fluidicly coupled or connected to a gravity drain, e.g., a sink drain or an in-sink garbage disposal, may be fluidicly coupled or connected to the air-gap portion  60  of the device  100 , while the hot and cold water lines  21 ,  23  may be fluidicly coupled or connected to the upper faucet assembly  30 , e.g., via the air-gap portion  60 . 
     In some implementations, the upper faucet assembly  30  includes a tubular spigot  32 , a base housing  34 , and a fluid mixing handle  36  coupled to hot and cold water valves. Although  FIGS. 2A through 2C  show a ball-type mixing valve handle  36 , those of ordinary skill in the art can appreciate that the invention is not to be construed as being limited thereto. The upper faucet assembly  30  may include other handle, e.g., translation-type mixing valve handles, and/or housing/body styles. 
     Faucets are well-known to those skilled in the art; hence, the conventional features of the upper faucet assembly  30  of the present invention will not be described in detail. Advantageously, faucet/air-gap system  100  enables one to install and plumb all of the supply lines and drain conduits to the system  100  without the spout  32  being attached to the base housing  34 , which facilitates installation. Furthermore, the modular nature of the present invention, including, for example, a base flange  42  and the air-gap portion  60 , provides a customization feature by enabling users to combine the base flange  42  and the air-gap portion  60  with a multiplicity of spigots  32 , faucet base housings  34 , and mixing valves with handles  36 . In short, one air-gap portion  60  size may fit multiple upper faucet assemblies  30  of various styles and designs. 
     In some variations, the base housing  34  is generally a hollow shell having a top opening through which the spigot  32  may be fluidicly coupled or connected to the hot and cold water lines  21 ,  23  via corresponding ports; a hollow arm portion  31  through and into which a valve cartridge or valve  35 , a compression nut  37 , and a handle dome  38  may be disposed for controlling flow and water temperature; and an overflow discharge outlet  39 , which will be described in greater detail below. 
     A proximal end of the valve  35  may be mechanically coupled to the fluid mixing handle  36 , so that manipulation, e.g., by translation and/or by rotation, of the handle  36  makes adjustments to the distal end of the valve  35 , controlling the mixture and quantities of hot and cold water delivered to the spigot  32 . In some variations, the compression nut  37 , the dome  38 , and the handle  36  may be removably attached, e.g., using a fastening device (e.g., set screw, bolt, and the like)  33 , to and within the plenum of the hollow arm portion  31 , providing a fluid-tight seal. 
       FIGS. 3, 4A, and 4B  show an exemplary embodiment of an above-counter portion  50  and a below-counter portion  40  of the faucet/air-gap system  100 . In some embodiments, the below-counter portion  40  ( FIG. 4B ) may include a hollow, substantially cylindrical portion  41  through which the hot  21  and cold water lines  23 , as well as the input conduit  17  and the drain conduit  16 , are disposed. In some variations, the hot  21  and cold water lines  23  are disposed adjacent to each other, retained in about one-half of the area of the substantially cylindrical portion  41 , while the input conduit  17  and the drain conduit  16  are disposed adjacent to each other, retained in the other one-half of the area of the substantially cylindrical portion  41 . An outer diameter of the cylindrical portion  41  may be sized so that the cylindrical portion  41  is able to fit cleanly or snugly in a conventionally sized faucet opening  24  in the counter  22  ( FIG. 1 ) provided for the faucet/air-gap system  100 . In some implementations, the cylindrical portion  41  is made of copper, brass, aluminum, stainless steel, or other structurally sound material. Advantageously, a distal end or upper portion of the cylindrical portion  41 , which is closer to the counter  22  when properly installed, may be counter-threaded to accept threadings provided on a base nut  43 . The mating threadings are structured and arranged to securely and removably attach the faucet base flange  42  and the cylindrical portion  41  to the counter  22 . 
     In some variations, with the below-counter portion  40  of the faucet/air-gap system  100 , a plurality of substantially circular or disk shaped sealing devices may be installed about the cylindrical portion  41  between the bottom of the counter  22  and the base nut  43 . For example, closest to the bottom of the counter  22 , a first sealing device  45 , e.g., a rubber, elastomer, and the like washer, may be removably disposed on and about the outer, peripheral surface of the cylindrical portion  41 , so as to abut the bottom of the counter  22 . A second sealing device  44  e.g., a metallic (e.g., steel, aluminum, brass, and the like) washer, may be disposed between the first sealing device  45  and the base nut  43 . In some variations, an outer diameter of the second sealing device  44  is larger than an outer diameter of the first sealing device  45 . During installation, as torque is applied to the base nut  43 , the threadings of the base nut  43  mate with the counter-threadings integrated into the upper portion of the cylindrical portion  41 , causing the base nut  43  to move, forcing each of the first sealing device  45  and the second sealing device  44  together and against the bottom of the counter  22 , providing a fluid-tight seal about the opening  24  in the counter  22 . 
     In some implementations, referring to  FIGS. 3 and 4A , the air-gap portion  60  may include a base portion  55 , a wall portion  54 , a removable block cover  52 , and a crown portion  56 . The base portion  55  may be disk-shaped and manufactured from a metal, alloy, hard plastic material, and the like. The base portion  55  may be dimensioned to provide a tight, interference fit with the faucet base flange  42  to create a fluid-tight seal. The faucet base flange  42  may be dimensioned to provide a tight, sliding fit with the faucet housing  34  to create a fluid-tight seal between the faucet base flange  42  and the faucet housing  34 . In some embodiments, the base portion  55  is formed to include one or more openings, e.g., four openings, to accommodate the plurality of fluid lines and conduits  16 ,  17 ,  21 ,  23 . In some implementations, the hot water  21  and cold water lines  23 , as well as the inflow line  17  from the dishwasher  18  ( FIG. 1 ), pass through, so as to extend beyond an upper face of the base portion  55 , while the outflow or drain line  16  may be formed flush with an upper face of the base portion  55 . 
     In some embodiments, the wall portion  54  of the air-gap portion  60  may be integral with or fixedly attached, e.g., bonded, welded, molded, and the like, and substantially perpendicular to the upper face of the base portion  55 . The wall portion  54 , which also may be manufactured from a metal, alloy, hard plastic material, and the like, may be structured and arranged to include a substantially planar surface  51  having a plurality of openings  61 , for releasably securing the block cover  52  to the planar surface  51  to provide a substantially fluid-tight seal against the planar surface  51 , and an outer, e.g., arcuate, surface  53  that may be configured to fit into the plenum of the faucet housing  34 . The wall portion  54  may form openings for the hot water  21  and cold water lines  23 . Advantageously, the wall portion  54  may be structured and arranged to isolate the hot water  21  and cold water lines  23  from the inflow  17  and outflow drain lines  16 . 
     In some embodiments, the crown portion  56  may be integral with or fixedly attached, e.g., bonded, welded, molded, and the like, in a cantilever and substantially perpendicular to the wall portion  54 . In some implementations, the crown portion  56  may be disk-shaped and manufactured from a metal, alloy, hard plastic material, and the like. The crown portion  56  may form openings for the hot water  21  and cold water lines  23 . Advantageously, the crown portion  56  may be structured and arranged to isolate the hot water  21  and cold water lines  23  from the inflow  17  and outflow drain lines  16 . The peripheral edge of the disk-shaped crown portion  56  may include a threaded opening  67 , which may be configured to receive a fastening device  46  ( FIGS. 2B and 2C ) for releasably attaching the faucet housing  34  to the air-gap portion  60 , and an annular groove  65  that is configured to retain a sealing device, e.g., an O-ring. Advantageously, when the faucet housing  34  is properly mounted over the air-gap portion  60 , the sealing device in the annular groove  65  may provide a fluid-tight seal above the air-gap channel  58  to prevent pressurized drain water from going anywhere except through the overflow discharge outlet  39 , in the event of a clogged drain. Furthermore, when properly mounted, an opening in the faucet housing  34  may be configured to register with the threaded opening  67  so that the fastening device  46 , e.g., a screw, bolt, and the like, may be inserted through the opening  67  to releasably attach the housing  34  to the air-gap portion  60 . Thus, a single fastening device  46  permits removal of the faucet housing  34 , for maintenance or repair. 
     In some implementations, the hot water  21  and cold water lines  23  pass through, so as to extend beyond an upper face of the crown portion  56 . The crown portion  56  may also include a key area  66  on an upper face at which a distal end of a faucet valve  35  may control the mixing temperature and flow volume of the hot and cold water flowing through the respective hot water  21  and cold water lines  23 . 
     The removable block cover  52  may be provided with the air-gap portion  60  to facilitate clean-out of a blocked or clogged drain. Advantageously, successive access to the air-gap portion  60 , to the block cover  52 , and to the air-gap channel  58  and the blockage or clog is facilitated by enabling one to access each above-the-counter, rather than below-the-counter where the confined space beneath the sink is a jumble of pipes and conduits and other obstructions. In some embodiments, the removable block cover  52  may be manufactured from a metal, alloy, hard plastic material, and the like, and may be structured and arranged to include a front surface  68  that may include one or more channels that, when the block cover  52  is properly attached to the wall portion  54 , may provide an outlet for pressurized waste water. A plurality of openings  69 , e.g., two openings, may be formed in the block cover  52  to be in registration with the threaded openings  61  in the wall portion  54  when the block cover  52  is properly attached to the wall portion  54 . Fastening devices  63 , e.g., set screws, bolts, and the like, may be used to releasably secure the front surface  68  of the block cover  52  to the wall portion  54 . 
     Advantageously, an air-gap channel  58  is formed into the block cover  52  at the front surface  68 . In some applications, the air-gap channel  58  may be formed as a U-shaped channel that includes a shorter leg that is in fluid communication with the outlet  57  of the dishwasher inflow conduit  17  and a longer leg that is in fluid communication with the inlet  59  of the outflow drain conduit  16 . In some variations, it may be desirable to have an outflow drain conduit  16  with a larger diameter than the inflow conduit  17 . To accommodate this, the diameter of the U-shaped channel  58  may be sized to form a diameter that corresponds to the outer diameter of the outlet  57  of the inflow conduit  17 ; however, the longer leg may be belled out immediately adjacent to the inlet  59  of the outflow drain conduit  16 . 
     The block cover  52  may be between about 1.5 and about 2 inches in height; between about 1.25 and about 1.75 inches in width; and about 0.5 to about 0.75 inches thick. In one implementation, the dimensions of the block cover may be 1.5 inches by 1.46 inches by 0.68 inches. 
     Those of ordinary skill in the art can appreciate that the legs of the U-shaped, air-gap channel  58  may actually be of the same length, such that one leg is not comparatively “longer” or “shorter” than the other. Recalling, however, that the inflow conduit  17  extends through the base portion  55 , so that its outlet  57  is a short distance above the upper face of the base portion  55 , as shown in  FIGS. 4A and 4B , when the block cover  52  is properly attached to the wall portion  54 , the distance from the outlet  57  of the inflow conduit  17  to the crown of the U-shaped channel is shorter than the distance from the inlet  59  of the outflow drain conduit  16 . In such an instance, the former is the “shorter” leg while the latter is the “longer” leg. 
     In the event that a there is a clog or blockage in the outflow drain conduit  16  and/or the air-gap channel  58 , a “fail safe” outlet  64 , which is in fluidic communication with the air-gap channel  58 , as well as with the overflow discharge outlet  39 , may be formed in the block cover  52  to provide an ambient release outlet for fluid entering the air-gap channel  58  from the inflow conduit  17  that would otherwise drain into the outflow drain conduit  16 . In some embodiments, the “fail safe” outlet  64  may be located in the block cover  52  so that the outlet  64  is between about 1.5 and about 2 inches above the counter top  22 . In one implementation, the “fail safe” outlet  64  may be located in the block cover  52  so that the outlet  64  is about 1.85 inches above the counter top  22 . In some variations, the “fail safe” outlet  64  may be located in the block cover  52  as close as possible to the air-gap base so that the outlet  64  is self-cleaning. An annular space  62  may be formed between the faucet housing  34  and the air-gap portion  60 , when the faucet housing  34  is properly disposed on the faucet base flange  42  about the air-gap portion  60 . The faucet base flange  42  may include an O-ring disposed in a groove formed in an underside thereof, to seal against the counter  22  and prevent liquid on the counter  22  from leaking into the sink base cabinet, especially in the event of a clog and discharge of waste water through the overflow discharge outlet  39 . Advantageously, when the faucet housing  34  is properly disposed on the faucet base flange  42 , the combination provides a fluid-tight seal at the faucet base flange  42 , for example, due to a stepped flange sealed with an O-ring, thereby causing any discharging fluid to travel from the “fail safe” outlet  64  to the overflow discharge outlet  39  via the annular space  62 . Consequently, fluid, e.g., dishwasher waste water, from the inflow conduit  17  that would otherwise drain into the outflow drain conduit  16  may be discharged into the sink  19  via the overflow discharge outlet  39  when the line  16  is clogged or otherwise blocked. 
     Advantageously, in some variations, the sealing arrangement may provide improved backflow prevention and/or prevent siphoning into a clean water source via the air-gap portion  60  by raising the effective flood level to the ambient overflow discharge outlet  39 , rather than at the level of the “fail safe” outlet  64 . 
     Having described the air-gap portion  60  integrated into the faucet  100 , a method of accessing an obstructed fluid flow channel within the faucet  100  to clear a clog or blockage in the outflow drain conduit  16  and/or the air-gap channel  58  will now be described. Advantageously, removing the faucet base housing  34  and the removable block cover  52  of the faucet/air-gap system  100  may be performed above sink counter  22  level and, moreover, removing the faucet base housing  34  and the removable block cover  52  may be performed without detaching one or more of the lines or conduits  16 ,  17 ,  21 ,  23  fluidicly coupled to the air-gap portion  60 . 
     Referring to  FIG. 5 , in a first step, the homeowner, handyman, and/or plumber may remove the faucet base portion  34  (STEP  1 ), e.g., by removing a set screw, a bolt, and the like, that connects the faucet base portion  34  to the air-gap portion  60 , exposing the latter. Fastening devices  67  may then be removed (STEP  2 ) to separate the block cover  52  from the air-gap portion  60 , exposing the air-gap channel  58 , inflow conduit  17 , outflow drain conduit  16 . With the air-gap channel  58 , inflow conduit  17 , outflow drain conduit  16 , the cause of the clog or blockage may be apparent, in which case the clog or blockage may be removed manually (STEP  3 ). If the cause of the clog or blockage is not apparent, a snake or other plumbing tool may be inserted into the inflow conduit  17  and/or the outflow drain conduit  16 . 
     O-ring seals on the hot and cold water conduits  21 ,  23  extending from the crown portion  56  align with corresponding inlets on the faucet base portion  34 , affording reliable, fluid-tight connections without the need to separately connect or disconnect the fluid lines. Accordingly, the four supply and drain lines need only be connected to the air-gap portion  60  during initial installation. All subsequent maintenance or replacement of the upper faucet assembly  30  may be completed quickly and easily, without the need to disconnect any supply or drain lines 
     It should be understood that alternative embodiments and/or materials used in the construction of embodiments, or alternative embodiments, are applicable to all other embodiments described herein. 
     The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The foregoing embodiments, therefore, are to be considered in all respects illustrative rather than limiting the invention described herein. Scope of the invention is thus indicated by the appended claims, rather than by the foregoing description, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.