Abstract:
A fencing system is constructed with thin-walled generally rectangular tubing. The large cross-section of the rectangular tubing provides significant structural strength. The posts can also be formed into rectangular cross-sections to achieve similar cross-sectional strength. The posts are provided with openings for the rails to be inserted. A compliant grommet is provided in each opening and allows for articulation in any direction, isolates the rail from the post to prevent metal-on-metal contact, provides cushioning to the rails upon impact, silences the rails in heavy wind, electrically isolates each fence section and centers the rail in the post opening. A system of clips or spring loaded lock pins attach to the ends of the rails allow the rails to be easily inserted into the posts, but prevents their removal. Alternatively, lock spacers may be inserted into each post systematically to limit the rail movement independently between any two posts to assure retention of the rails and to allow easy rail removal upon removal of the lock spacers.

Description:
1. CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Application Ser. No. 61/150,194, filed Feb. 5, 2009, the subject matter of which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates to a fencing system. More particularly, the invention relates to a thin-walled, tubular metal panel fencing system. In addition, the invention relates to a method of installing and maintaining the fencing system. 
         [0004]    2. Discussion of the Related Art 
         [0005]    Traditional horse farm and some residential fencing have been constructed from planks of wood nailed to wooden posts. Typically, these wooden fencing systems utilize 4 inch or 6 inch square posts with 0.75 inch thick by 5.5 inch wide panels. The posts are installed 3 to 4 feet deep in the ground and are typically surrounded by a concrete footing. The panels are then nailed to one of the faces of the posts and the fencing system is then hand painted. The drawbacks with this fencing system are high maintenance costs and short cosmetic and structural life spans. Painted wood requires frequent painting due to the tendency of wood to absorb moisture, expand and contract with temperature changes, attract chewing by horses, and build up mold and mildew. Posts can be quickly rotted by moist ground and are expensive to replace. The typical life span of a wooden fencing system is 7 to 10 years and can be far less in humid climates. This system also provides health concerns to animals due to cracking, splintering, loose nails, cribbing or chewing damage. In addition, because the system is easily broken, animal escapes occur far too often. 
         [0006]    In response to problems posed by wood fencing systems, vinyl panel fencing systems were developed. Vinyl fencing systems provided lower maintenance and longer life spans at a small price premium over wood fencing systems. However, vinyl fencing systems have their own drawbacks. Vinyl fencing systems loose their gloss and their surfaces chalks much faster than modern paints due to exposure to the weather, resulting in a limited color selection. In addition, the surfaces cannot be repainted in the field. The panels also become brittle from age or exposure to the weather, making them susceptible to breakage by large animals. Further, the panels could drop out because of thermal expansion and contraction of the rails and posts. Similar to wood systems, these vinyl fences are easily broken and can shard to impale the animal or allow easy escape upon breakage. Additionally the production of vinyl (poly vinyl chloride) is highly detrimental to the environment and these materials are not recycled. 
         [0007]    More recently, galvanized and powder-coated round steel pipe tubing fencing systems have been developed. These fencing systems solve many of the problems associated with wood and vinyl fencing systems; however, the pipe tubing systems lack aesthetic value. In particular, pipe tubing fencing systems do not have the panel look that the market is used to and desires to maintain. 
         [0008]    The need therefore has arisen to provide a structurally sound fencing system that could be maintenance free for many years. The fencing system preferably maintains the traditional panel fence appearance and utilizes modern paints to maintain color and resist weathering. The system should match or exceed the steel round pipe style strength which greatly surpasses that of the wood and vinyl. The system should be animal friendly thus eliminating the many health issues associated with the wood and vinyl products. In order to create a panel system in a material such as coated steel or aluminum with hollow posts and rails there needed to be a system for protection of the coated surfaces at the post to rail interface while still allowing articulation in the up and down, as well as the left and right, directions to allow for installation over varying terrain. Finally, the fencing system should preferably be easily installed with standard tools and be cost competitive with existing fencing systems. Fence panels should be replaceable in the event of damage such as by falling trees. 
       SUMMARY OF THE INVENTION 
       [0009]    In accordance with a first aspect of the invention, at least some of the above-identified needs are met by providing a fencing system constructed with thin-walled non-circular, preferably at least generally rectangular tubing. The tubing can be formed to provide rails in the form of rectangular panels to provide the desired aesthetic look. The large cross-section of the rectangular panels provides significant structural strength. The posts can also be formed into rectangular cross-sections to achieve similar cross-sectional strength. 
         [0010]    The posts are provided with openings for the rails to be inserted. A compliant material, preferably an elastomeric grommet, may be provided in each opening. The compliant material allows for articulation in any direction, isolates the rail from the post to prevent metal-on-metal contact, and centers the rail in the post opening. This compliant material will also provide a cushioning of the rail in the event of animal impact to reduce the potential for injury. The grommet also reduces or eliminates any potential for noise due to movement of the rails in the wind. 
         [0011]    Additionally, a fastening system, made up of clips attaching to the ends of the rails, is provided that allows the rails to be easily inserted into the posts without the use of specialized tools, but prevents their removal. This fastening system simplifies and speeds up fence installation. Further, the rail clips allow for independent thermal expansion and contraction of each rail, eliminating the potential of rails falling out or putting pressure on subsequent posts. A similar system of rail retention spring loaded latch pins can provide similar benefits. 
         [0012]    An alternative or supplemental rail retention method provides lock spacers insertable into the hollow posts. The lock spacers limit longitudinal or in-line rail movement, thus assuring their secure mounting in the post. They also facilitate rail removal for maintenance or repair. These and other aspects, advantages, and features of the invention will become apparent to those skilled in the art from the detailed description and the accompanying drawings. It should be understood, however, that the detailed description and accompanying drawings, while indicating preferred embodiments of the present invention, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof. It is hereby disclosed that the invention include all such modifications. 
         [0013]    These systems are compatible with round rails as shown in the illustrations for areas where this aesthetic is preferred. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    Preferred exemplary embodiments of the invention are illustrated in the accompanying drawings, in which like reference numerals represent like parts throughout, and in which: 
           [0015]      FIG. 1  is a perspective view of a fencing system in accordance with an exemplary embodiment, viewed from the front, left, and top; 
           [0016]      FIG. 2  is a perspective view of a portion of the fencing system of  FIG. 1 , viewed from the front, right, and below the connection; 
           [0017]      FIG. 3  is a perspective view of a fence post of the fencing system of  FIG. 1 , which is configured for two-way connection of fence rails, viewed from the front, left, and top of the fence post; 
           [0018]      FIG. 4  is a perspective view of a fence post of the fencing system of  FIG. 1 , which is configured for four-way connection of fence rails, viewed from the front, left, and top of the fence post. 
           [0019]      FIG. 5  is a front elevation view of the fence post of  FIG. 4 ; 
           [0020]      FIG. 6  is a perspective view of a fence rail of the fencing system of  FIG. 1 , viewed from the front, left, and top of the fence rail; 
           [0021]      FIG. 7  is a cross-section view of the fence rail of  FIG. 6 ; 
           [0022]      FIG. 8  is a perspective view of the portion of the fencing system of  FIG. 2  viewed at the cross-section  8 - 8  as shown in  FIG. 2 , viewed from the front, left, and below the connection; 
           [0023]      FIG. 9  is an expanded perspective view of the encircled area  9  in  FIG. 8 , viewed from the front, right, and below the connection; 
           [0024]      FIG. 10  is a perspective view of a first rail clip of the fencing system of  FIG. 1 , viewed from the front, left, and bottom of the rail clip. 
           [0025]      FIG. 11  is a right side elevation view of the rail clip of  FIG. 10 ; 
           [0026]      FIG. 12  is a perspective view of a grommet retainer of the fencing system of  FIG. 1 , viewed from the left, rear, and top of the grommet retainer; 
           [0027]      FIG. 13  is a left side elevation view of the grommet retainer of  FIG. 12 ; 
           [0028]      FIG. 14  is a perspective view of a grommet of the fencing system of  FIG. 1 , viewed from the front, right, and top of the grommet; 
           [0029]      FIG. 15  is a front elevation view of the grommet of  FIG. 14 ; 
           [0030]      FIG. 16  is a side elevation view of the grommet of  FIG. 14 ; 
           [0031]      FIG. 17  is a perspective view of a line post lock spacer assembly usable in place of or supplemental to the rail clip of  FIGS. 10 and 11 ; 
           [0032]      FIG. 18  is a partial cut away perspective view showing the lock spacer assembly of  FIG. 17  installed in a fencing system; 
           [0033]      FIG. 19  is an enlarged view of a portion of the system illustrated in  FIG. 18 ; and 
           [0034]      FIG. 20  is a top plan view of a post and adjacent rail sections of  FIGS. 18 and 19 ; 
           [0035]      FIGS. 21A , B, C, and D show an alternative construction for the line lock spacer of  FIG. 17 ; 
           [0036]      FIGS. 22  A through L show an alternative spring loaded rail locking system performing a similar function to that of  FIG. 8 ; and 
           [0037]      FIGS. 23  A through J show a round rail system with a similar post as used in  FIGS. 1 and 2 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0038]    Referring to  FIG. 1 , a fencing system  10  constructed in accordance with an exemplary embodiment of the invention is illustrated.  FIG. 1  illustrates a three-rail fencing system with examples of both two-way and four-way post interconnections. It is contemplated that this fencing system  10  may also be constructed as a two or a four-rail fencing system, not illustrated, and alternately, the fencing system  10  may use any other number of rails as appropriate in a particular application. The rail system comprises fence members in the form of rails or rail panels  20  and posts  30  and  30 ′ that support the rails. The rails  20  are mounted in openings  32  in the posts  30  and  30 ′ by compliant couplers  80  and clips  40  in a manner that permits the rails  20  to extend at vertical or horizontal angles relative to the posts  30  and  30 ′. All components of the fencing system  10  are designed to render the system  10  as a whole easy to assemble, versatile, and aesthetically attractive. 
         [0039]    Referring to  FIGS. 3-7 , the fence members forming the rails  20  and posts  30 ,  30 ′ of the fencing system are preferably formed from thin-walled tubing in order to maximize the strength-to-weight ratio of the fence members while also providing a durable, aesthetically attractive, low maintenance fence. The fence members can be constructed out of, but are not limited to coated steel, aluminum extrusions, and aluminum composites with various profile and length stiffeners. Preferably, the fence members are constructed out of two-sided galvanized and architectural powder coated steel welded tubing. Galvanized steel was chosen as a relatively low-cost, yet durable material. Powder coating was chosen as a durable, aesthetically attractive finish that also greatly enhances the corrosion resistance of the galvanized system. The preferred thickness of the tubing will vary, e.g., with the application and the materials selected for the tubing. The tubing should be thin enough to reduce weight and costs but thick enough to provide sufficient strength and rigidity for the desired application. In the illustrated embodiment in which the fencing system is designed to fence-in large livestock such as horses and the fence members are formed from two-sided galvanized and architectural powder coated steel welded tubing, the rail tubing should have a thickness of about 1.0 to 1.5 mm and preferably about 1.2 mm with optional rail reinforcements within the rail that are considerably shorter than the rail itself and with the posts averaging about 1.4 mm in wall thickness. 
         [0040]    The rails  20  can be formed into a rounded-corner, preferably at least generally rectangular shape in order to reproduce the wood panel look. As best seen in  FIGS. 6 and 7 , that they have opposed sets of walls  22 ,  24 , an upper wall  26 , and a bottom wall  28 . In the illustrated embodiment, the rails  20  are designed with a width of 35 mm and a height of 130 mm. Referring to  FIGS. 3-5 , the wall  26 ,  28  are very thin—having a thickness of about 1.2 mm or less. The walls of the presently preferred embodiment are formed from two side-galvanized low carbon steel plates that are welded together to from a rectangular tube with rounded corners. 
         [0041]    Referring to  FIGS. 3-5 , the posts  30 ,  30 ′ may have any desired cross-sectional shape and dimensions but, in the illustrated embodiment, have a rounded rectangular section with opposed relatively long sidewalls  34  having a width of 130 mm and opposed relatively short sidewalls  36  having a breadth of 90 mm. The length of the posts will vary with the intended application, particularly with the fencing height as determined by the number and spacing of rails. The walls  34  and  36  have a thickness of about 1.4 mm or less and, like the posts  20 , are formed two side-galvanized low carbon steel plates that are welded together to from a rectangular tube with rounded corners. The posts  30 ,  30 ′ should be sufficiently long to be imbedded about 3.5 feet into the ground while extending high enough above ground to receive the desired number of rails at the desired spacing’ In the illustrated embodiment, they are 6′ to 8.5′ long. Both the posts  30 ,  30 ′ and the rails  20  preferably are painted with a powder-coat pant. 
         [0042]    Referring to  FIGS. 4 ,  5 ,  8 , and  9 , the posts  30  and  30 ′ are provided with rail openings  32  integral to the posts  30  and  30 ′ in order to reduce installation time and cost. The couplers  80  preferably comprise grommets positioned in the openings  32  between the rails and the posts  30 . While the grommets  80  may be installed at the time of system installation, they preferably are inserted into the rail openings  32  at the factory. The installation of the fencing system is therefore quick and inexpensive. The installer first installs the posts  30  and  30 ′ into the ground. Next, the rail retaining clips  40  are affixed to the ends of each rail  20 . A first end of each of the rails  20  is inserted into a first rail opening  32  in a first post  30 , and the rail  20  is recessed a sufficient distance inside the post  30  to provide clearance between the opposite end of the rail  20  and a second post  30  supporting the opposite end of the rail  20 . The opposite end of the rail  20  is then inserted into a second rail opening  32  in the second post  30 , securing the rail  20  between the two posts  30 . The rail retaining clips  40  or alternate spring loaded pins of  FIG. 22  secure both ends of the rails  20  into the corresponding posts  30 , allowing the fence system  10  to be quickly installed without the need for any special tools or equipment. 
         [0043]    As seen in  FIGS. 3-5 , the fence posts  30  are provided with pre-formed rail openings  32  in order to simplify installation. In an especially preferred embodiment, the openings  32  comprise horizontal bores extending through the fence posts  30 . Each opening  32  should have at least generally the same shape as cross-sectional shape of the OD of the grommets (detailed below). Corner posts  30 ′ have openings  32  in two adjacent sides, while the remaining posts  30  have openings  32  and in opposed sides. An alternate round rail construction is illustrated in  FIGS. 22A-22L . 
         [0044]    In the exemplary embodiment, at least one rail retaining clip  40  is attached to each end of the rail  20 . Preferably, one retaining clip  40  is attached to the end of each of the upper wall  26  and lower wall  28  of the rail  20 , as shown in  FIGS. 2 and 8 . The rail  20  and the attached retaining clip  40  are inserted through the rail opening  32  and compliant structure  80 , where the retaining clip  40  holds the rail  20  in place. These clips allow free thermal expansion and contraction of each rail  20  independently of all the other parts without the potential of rail panel falling out or applying pressure on the posts  30  or  30 ′. This thermal expansion problem is quite limited with the steel system in comparison to for very long runs of welded or hard-connected steel systems, in which the much larger thermal expansion can cause the gate post to move enough to cause malfunctioning of a gate latch. Thermal expansion is also a much bigger problem with plastic fence systems as the expansion rate can be from 4 to 10 times that of steel for a given length. 
         [0045]    Referring to  FIGS. 10 and 11 , a preferred embodiment of the rail retaining clip  40  is illustrated. The rail clip  40  is formed from high carbon steel and is bent such as by stamping to include the features hereafter described includes a channel  44  which fits over the end or the top or bottom wall  26  or  28  of the rail  20 . A lanced bite tab  45  is formed into one side of the channel  44  in order to resist removal of the rail  20  once it has been inserted into the channel  44 , securing the retaining clip  40  to the rail  20 . The rail clip  40  also includes a flexible tab  42  that is about 11 mm long when in its uncompressed state. This flexible tab  42  is designed to fold over as the rail  20  is inserted through the rail opening  32  and to then spring back to its original shape inside the rail post  30 , securing the rail  20  to the post  30 . The one-way fastening system allows the rails  20  to be easily inserted into the posts  30 ,  30 ′ while preventing their removal. This simplifies and speeds up fence construction by eliminating the need for screws and any drilling that could damage the coating system and therefore the corrosion free life span 
         [0046]    The alternate spring loaded rail pin system shown in  FIGS. 22A-22L  acts similarly while having the added advantages of being centered on the wide side of the rail to make installation symmetrical and also being capable of being installed in each rail before shipping at the factory without causing issues in loading for shipment. 
         [0047]    Referring to  FIGS. 12 and 13 , a preferred embodiment of a grommet retaining clip  60  is illustrated. The grommet clip  60  preferably is a stamped clip formed from the same high carbon steel as the rail clip  40 . It is generally U-shaped, creating a first interlock channel  62  to fit over the grommet  80  and a second, smaller exterior channel  64  formed on the outside of one leg of the first channel  62 . The first channel  62  contains an interlock bite tab  66  in order to secure the grommet  80  into the channel  62 . The second channel  64  connects to the end of the opening  32  of a post  30  at either the upper or lower portion of one of the rail openings  32  and contains a pair of bite tabs  68  to secure the grommet clip  60  to the post walls  36 . The grommet clip  60  holds the grommet  80  in place during shipping and helps prevent compression of the grommet  80  during use. 
         [0048]    Referring to  FIGS. 14-16 , a preferred embodiment of the compliant surface  80 , preferably a grommet, is illustrated. The grommet  80  may be constructed of any of several natural, synthetic, or compostic elastomeric materials. It preferably is constructed of Santoprene 101-51 thermoplastic elastomer or EPDM rubber. Each grommet  80  functions to center the rail  20  within the rail opening  32 . It should be noted at this time that the opening  32  is substantially longer than the height of the rail section so as to provide gaps between the upper and lower ends of the opening and the top and bottom surfaces  26 ,  28  of the rail  20 . Smaller gaps are formed between the sides  22  and  24  of the rail  20  and the sides of the opening  32 . The grommet  80  fills these gaps while centering the rail  20  in the opening  32  and accommodating up and down or side-to-side articulation of the rail  20  within the rail opening  32 . The rail articulation may be up to 15 degrees side to side and as great as 23° up and down while still allowing the grommet  80  to set against both the post  30  and the rail  20 , thus hindering potentially corrosive water from entering the interior of the posts. The grommet  80  also prevents metal-to-metal contact between the painted surfaces of the post  30  and the rail  20  to prevent scratching and subsequent corrosion of either surface. It also prevents electrical conductivity in the case of a lightning strike on or near any one section of the fence. Finally the grommet cushions the rails during animal impact and quiets the entire system in heavy winds. To achieve these effects, grommet  80  has a central opening  82  of proper shape and size to allow a fence rail  20  to be inserted therein. The grommet  80  has a surface  84  disposed around the periphery of the grommet  80  that engages the wall of the post  30  around the perimeter of a rail opening  32 . The sides of the surface  84  are formed from inwardly-extending protrusions  86  that extend the length of the opening  32  and that project into the post  30 ,  30 ′ beyond the inner surface of the post wall. In addition, two end portions  88  of the grommet are formed of an appropriate shape and size to interface with the grommet retaining clip. They are slotted in order to maintain adequate stiffness while being materially conservative. 
         [0049]    Referring to  FIGS. 17-20 , a lock spacer assembly  90  is illustrated that can supplement or even replace the rail retainer clips  40 . Lock spacer assemblies allow easier shipping, installation and maintenance than the clip system. A lock spacer assembly  90  is inserted into each post  30  from above. It includes a central spar  92  on which an upper stop  94  and a number of lock stops or spiders  95  are mounted. All components preferably are formed from extruded aluminum with the upper stop  94  and spiders  96  being crimped onto the spar  92  at the desired locations. An alternate construction of all steel metal stampings is shown in  FIGS. 21A-21D . Steel stampings stapled to wood bars can also serve the same function. 
         [0050]    The upper stop  94  extends from the upper end portion of the spar  90  so as, in use, to rest on top of the uppermost rail  20  in the fencing system  10 , hence properly locating the lock spacer assembly  90  in the post  30  as best seen in  FIG. 20 ; the upper stop  94  includes a pair of longitudinally extending legs  96 ,  98  that rest on top of the ends of two adjacent rail sections  20  to locate the lock spacer assembly  90  in position. It also includes a pair of laterally extending legs  100 ,  102  that extend to just inside the inner surface of the lateral post walls  34  to prevent the lock spacer assembly  90  from twisting. The legs  96 ,  98  and  100 ,  102  are offset from one another relative to longitudinal and lateral centerlines of the spar  92  in order to accommodate articulation of the rail sections. 
         [0051]    The spiders  95  are positioned in each rail opening  32  when the lock spacer assembly  90  is inserted into the post  30  with the upper stop  94  resting on top of the uppermost rail. Each spider  95  has first and second opposed sections  104 ,  106  each of which is engaged by the end of a respective rail section  20 . Each section  104 ,  106  includes a curved inner section  108  that is engaged by the end of the associated rail section  20  and first and second arms  110 ,  112  that extend outwardly from the curved section  108  and that flank the sides  24 ,  26  of the rail  20  with a substantial gap therebetween. The arms  110 ,  112  extend outwardly from the spar  92  toward the inner surface of the post  30  such that, upon system assembly, the ends of the arms  110 ,  112  of one of the sections  104  or  106  are jammed against the inner surface of the associated end wall  36  of the post  30 , hence locking the spider  95  and the lock spacer assembly  90  as a whole in position and, therefore, limiting the rail movement and preventing the rail from being removed with the lock spacer in place. The curvature of the inner section  108  accommodates side-to-side articulation of the rail  20  while assuring that each rail section extends the same distance out of the post  30  regardless of its degree of articulation. 
         [0052]    To assemble a fencing system using the lock spacer assemblies  90 , the posts  30  with integral rail openings  32  and pre-inserted grommets  80  are inserted into the ground. Next, a first set of rails  20  is inserted into first and second adjacent posts. A first lock spacer assembly  90  is inserted into the first post  30  in the line, and each rail is pulled up tightly to the first lock spacer assembly  90 . More specifically, upon being inserted into the opening  32 , the end of the rail  20  engages the curved section  108  of one section  104  of one of the spiders  95  and drives the end of the arms  110  and  112  of the opposite section  106  against the inner surface of the post  30 . A second lock spacer assembly  90  is dropped into the second post up the line, and a set of rails second rail  20  is installed by inserting it fully into the opening  32  in the third post  30  in the line, swinging it inline with the second post, and inserting it into the lock spacer assembly  90  of the second post. The process is then repeated down the line. Once the rails are assembled they have clearance to the lock spacers to accommodate thermal expansion within each section independently. 
         [0053]    Once fully assembled, the fencing system  10  is extremely strong, highly durable, and virtually unbreakable—at least when subjected to stresses typically imposed on it by horses and other animals. However, the thin metal panels forming the rails  20  are relatively flexible due to their long length and section shape, and that flexibility is enhanced by the cushioning effects of grommets  80 . A fence section therefore will flex several inches and spring back if an animal falls on or runs into it—drastically reducing the chances of animal injury when compared to rigid fences. 
         [0054]    Maintenance is very easy with this system. All a worker need do is to remove two sequential lock spacer assemblies  90  in a line to provide room for rail movement relative to the posts  30 . The worker then pulls the rail  20  fully into the first post  30  in line, allowing the opposite end of the rail to be removed from the next post  30 . He then articulates the rail  20  to clear the second post  30  and pulls the rail  20  out from the first post  30 . 
         [0055]    The lock spacer assembly  90  described above is optimized for use with in-line posts. The spiders  95  of the lock spacer assemblies  90  are optimized for three way and four way corner posts would have different geometries but utilize the same principal as described above. Specifically, the spiders  95  of the lock spacer assemblies allow each rail section to be independently secured from rail movement or removal. Removal of any particular rail section does not compromise any other section of the fence. There thus can be no accumulated tolerance due to erroneous post spacing from one post to the next. This greatly eases the precision requirements when building the fence system. 
         [0056]    It can thus be seen that the system of rail clips  40  or rail spring pins and/or the system of lock spacer assemblies  90  both work and are even usable together, but either system can be used alone. Use of the lock spacer system facilitates system disassembly. It is also easier to transport without damaging the paint on the system components. 
         [0057]    Although the best modes contemplated by the inventors of carrying out the present invention is disclosed above, practice of the present invention is not limited thereto. It will be manifest that various additions, modifications, and rearrangements of the features of the present invention may be made in addition to those described above without deviating from the spirit and scope of the underlying inventive concept. The scope of some of these changes is discussed above. The scope of other changes to the described embodiments that fall within the present invention but that are not specifically discussed above will become apparent from the appended claims and other attachments.