Patent Publication Number: US-2021164724-A1

Title: Structual formations incorporated within a vacuum insulated structure

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application is a continuation of U.S. patent application Ser. No. 16/309,752 filed Dec. 13, 2018, entitled STRUCTURAL FORMATIONS INCORPORATED WITHIN A VACUUM INSULATED STRUCTURE, which is a national stage of International Application No. PCT/US2016/055304 filed Oct. 4, 2016, entitled STRUCTURAL FORMATIONS INCORPORATED WITHIN A VACUUM INSULATED STRUCTURE FOR VACUUM BOW AVOIDANCE, the entire disclosures of which are hereby incorporated herein by reference. 
    
    
     FIELD OF THE DEVICE 
     The device is in the field of vacuum insulated structures, and more specifically, a vacuum insulated structure incorporating structural geometries for avoiding vacuum bow resulting from the expression of gas during formation of the vacuum insulated structure. 
     SUMMARY 
     In at least one aspect, an appliance includes an outer wrapper and an inner liner that are connected to define a structural cabinet with an insulating cavity defined between the outer wrapper and the inner liner. An insulating material is disposed within the insulating cavity, wherein an at least partial vacuum is defined within the insulating cavity. The at least partial vacuum defines a pressure differential between the exterior of the structural cabinet and the insulating cavity. The pressure differential defines an inward compressive force. Wrapper structural reinforcements are disposed proximate the outer wrapper. Liner structural reinforcements are disposed proximate the inner liner, wherein each of the wrapper and liner structural reinforcements extend into the insulating cavity and are free of engagement with one another. The wrapper and liner structural reinforcements are positioned to resist the inward compressive force. 
     In at least another aspect, an insulating structure for an appliance includes first and second members that are attached to one another to define an insulating cavity therebetween. An insulating material is disposed within the insulating cavity. First structural reinforcements are disposed proximate the first member. Second structural reinforcements are disposed proximate the second member, wherein the first and second structural reinforcements are free of engagement with one another such that the insulating material extends continuously throughout the insulating cavity. 
     In at least another aspect, a method of forming a structural cabinet for an appliance includes disposing a plurality of wrapper structural reinforcements proximate an outer wrapper, disposing a plurality of liner structural reinforcements proximate an inner liner, attaching the outer wrapper to the inner liner to define an insulating cavity therebetween with the wrapper and liner structural reinforcements extending from the outer wrapper and inner liner, respectively, into the insulating cavity. The wrapper and liner structural reinforcements are free of contact with one another and are spaced apart from one another by a cavity space. An insulating material is disposed within the insulating cavity and fills the cavity space. Gas is expressed from the insulating cavity to define an at least partial vacuum within the insulating cavity, wherein the at least partial vacuum generates an inward compressive force exerted against the inner liner and the outer wrapper toward the insulating cavity. The insulating cavity is sealed, wherein the wrapper and liner structural reinforcements are positioned to oppose the inward compressive force and maintain the outer wrapper and the inner liner at a substantially consistent distance to maintain the volume of the cavity space between the wrapper and liner structural reinforcements. 
     These and other features, advantages, and objects of the present device will be further understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a front perspective view of an appliance incorporating aspects of the structural geometries proximate the inner liner and outer wrapper of the structural cabinet; 
         FIG. 2  is a perspective view of an appliance incorporating an aspect of the structural geometries incorporated within the inner liner and outer wrapper of a structural cabinet for an appliance; 
         FIG. 3  is a side elevational view of the appliance of  FIG. 2 ; 
         FIG. 4  is a side elevational view of an appliance incorporating an aspect of the structural geometries incorporated within the inner liner and outer wrapper of the appliance; 
         FIG. 5  is a cross-sectional view of an appliance incorporating an aspect of the structural geometries within reinforcing panels disposed within the insulating cavity of the structural cabinet; 
         FIG. 6  is a cross-sectional view of the structural cabinet of  FIG. 3  taken along line VI-VI; 
         FIG. 7  is a cross-sectional view of a portion of a structural cabinet incorporating an aspect of the structural geometries incorporated within the inner liner and outer wrapper of the structural cabinet; 
         FIG. 8  is a cross-sectional view of the structural cabinet of  FIG. 4  taken along line VIII-VIII; and 
         FIG. 9  is a linear flow diagram illustrating an aspect of a method for forming a structural cabinet for an appliance. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     For purposes of description herein the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the device as oriented in  FIG. 1 . However, it is to be understood that the device may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. 
     As illustrated in  FIGS. 1-8 , reference numeral  10  generally refers to an insulating structure incorporated within an appliance  16 . It is contemplated that the insulating structure  10  can be in the form of a vacuum insulated structural cabinet  12  or a vacuum insulating panel  14  that can be used as an insulation member for the appliance  16 . According to the various embodiments, the appliance  16  can include an outer wrapper  18  and an inner liner  20  that are connected to define the structural cabinet  12  with an insulating cavity  22  defined between the outer wrapper  18  and the inner liner  20 . An insulating material  24  is disposed within the insulating cavity  22 . An at least partial vacuum  26  is defined within the insulating cavity  22 , where the at least partial vacuum  26  defines a pressure differential  28  between the exterior  30  of the structural cabinet  12  and the insulating cavity  22 . This pressure differential  28  serves to define an inward compressive force  32  that is exerted upon both of the outer wrapper  18  and the inner liner  20  and tends to bias the outer wrapper  18  and the inner liner  20  toward the insulating cavity  22  of the structural cabinet  12 . Wrapper structural reinforcements  34  are disposed proximate the outer wrapper  18  and liner structural reinforcements  36  are disposed proximate the inner liner  20 . It is contemplated that each of the wrapper and liner structural reinforcements  34 ,  36  are configured to extend into the insulating cavity  22 . Additionally, the liner and wrapper structural reinforcements  36 ,  34  are free of engagement with one another, such that the insulating material  24  extends continuously through the insulating cavity  22  and extends between and separates the inner liner  20  and outer wrapper  18 , as well as the wrapper and liner structural reinforcements  34 ,  36  from one another. It is further contemplated that the wrapper and liner structural reinforcements  34 ,  36  are shaped and positioned to resist the inward compressive force  32  generated by the pressure differential  28  of the at least partial vacuum  26  within the insulating cavity  22 . 
     Referring again to  FIGS. 1-8 , the wrapper and liner structural reinforcements  34 ,  36  include structural geometries  50  that are positioned proximate the outer wrapper  18  and inner liner  20 , respectively. The wrapper and liner structural reinforcements  34 ,  36  may be in the form of corrugations within the structural cabinet  12  that resist bending, warping, bowing, or other deflection, along at least one axis  52 . As discussed above, an inward compressive force  32  is exerted upon both the outer wrapper  18  and the inner liner  20  due to the pressure differential  28  between the exterior  30  of the structural cabinet  12  and the at least partial vacuum  26  within the insulating cavity  22 . The corrugations, ridges, or other similar structural geometries  50  of the outer wrapper  18  and inner liner  20  serve as structural reinforcements that add rigidity to the components of the structural cabinet  12  to resist this inward compressive force  32 . It is contemplated that the wrapper and liner structural reinforcements  34 ,  36  can be positioned to define distinct reinforcing sections  54  within the structural cabinet  12 . Each of these distinct reinforcing sections  54  includes structural geometries  50  that are aligned along respective axes, where each distinct reinforcing section  54  resists deflection along each respective axis  52  defined within that particular distinct reinforcing section  54  of structural geometries  50 . 
     By way of example, and not limitation,  FIGS. 3 and 4  show exemplary configurations of wrapper structural reinforcements  34  that are defined within the outer wrapper  18 . These wrapper structural reinforcements  34  are oriented vertically and horizontally to allow for the resistance of deflection as a result of the inward compressive force  32  in at least two directions. It is contemplated that the wrapper and liner structural reinforcements  34 ,  36  can be positioned within the distinct reinforcing sections  54  along a plurality of respective axes  52  to resist deflection in a plurality of distinct axial directions. In this manner, the inner liner  20  and outer wrapper  18  of the structural cabinet  12  can be adapted to substantially resist deflection in various directions during and after formation of the at least partial vacuum  26  within the insulating cavity  22 . 
     Referring again to  FIGS. 2-4 , it is contemplated that the wrapper structural reinforcements  34  and the liner structural reinforcements  36  can be defined within the outer wrapper  18  and the inner liner  20 , respectively. In this manner, the wrapper and liner structural reinforcements  34 ,  36  serve to define visible relief patterns within the outer wrapper  18  and inner liner  20  of the structural cabinet  12 . It is contemplated that the outer wrapper  18  can be a metallic member that includes the plurality of integral ridges that define the wrapper structural reinforcements  34 . As discussed above, the integral ridges can be in the form of corrugations that resist deflection that may be caused by the inward compressive force  32  generated through the at least partial vacuum  26  within an insulating cavity  22 . As discussed above, the plurality of integral ridges within the outer wrapper  18  can be positioned to define distinct reinforcing sections  54  within the outer wrapper  18 . Each distinct reinforcing section  54  can define a distinct ridge orientation, such as vertical, lateral, diagonal, arcuate, irregular, or other similar orientation. 
     Referring again to  FIGS. 3 and 4 , the various distinct reinforcing sections  54  can include a first wrapper section and a second wrapper section. The integral structural geometries  50  of the first wrapper section can be oriented to be substantially perpendicular to the integral structural geometries  50  of the second wrapper section. It is further contemplated that the various distinct reinforcing sections  54 , which can include the various wrapper sections and liner sections can be oriented to be perpendicular with respect to one another or can be disposed at other varying angles and configurations with respect to the other wrapper and liner sections defined within the structural cabinet  12 . 
     It is contemplated that the structural geometries  50  of the various distinct sections can include ridges, scallops, corrugations, undulations, folds, bends, relief patterns, combinations thereof and other similar structural geometries  50 . These structural geometries  50  can be formed through molding, rolling, stamping, bending, folding and other similar shaping processes. 
     While the various structural geometries  50  are defined within  FIGS. 2-4  to be within sidewalls  74  of the structural cabinet  12 , it is contemplated that the wrapper and liner structural reinforcements  34 ,  36  can be defined within each of the inner and outer walls of the structural cabinet  12 . These structural walls  60  can include, but are not limited to, the top wall  70 , bottom wall  72 , sidewalls  74 , back wall  76 , interior walls, “dog house” walls, interior mullions  78 , and other various structural walls  60  of the structural cabinet  12 . 
     Referring now to  FIG. 5 , it is contemplated that the wrapper and liner structural reinforcements  34 ,  36  can be defined within a wrapper reinforcing panel  90  and a liner reinforcing panel  92 , respectively. The wrapper and liner reinforcing panels  90 ,  92  can be positioned proximate the outer wrapper  18  and the inner liner  20  and within the insulating cavity  22 . In this manner, the wrapper and liner reinforcing panels  90 ,  92  may be placed next to or can be attached to interior surfaces  94  of the outer wrapper  18  and inner liner  20 . In such an embodiment, the visible exterior  30  of the outer wrapper  18  and inner liner  20  can be smooth and flat, while the insulating cavity  22  can be reinforced through the use of the wrapper and liner reinforcing panels  90 ,  92  that contain the wrapper and liner structural reinforcements  34 ,  36 . In this manner, the wrapper and liner reinforcing panels  90 ,  92  serve to prevent inward deflection of portions of the structural cabinet  12  as a result of the inward compressive force  32 . 
     Referring now to  FIG. 7 , it is contemplated that the wrapper and liner structural reinforcements  34 ,  36  can be defined by structural members  100  that are attached to the interior surfaces  94  of the outer wrapper  18  and inner liner  20 . According to various embodiments, the wrapper and liner structural reinforcements  34 ,  36  can be a plurality of steel members, such as steel angles that are positioned within the insulated cavity and attached to the inner liner  20  and outer wrapper  18  to resist inward deflection that may be caused by the inward compressive force  32  generated by the pressure differential  28 . In such an embodiment, it is contemplated that the wrapper and liner structural reinforcements  34 ,  36  can be thickened portions of the inner liner  20  and outer wrapper  18 , attached reinforcing members, and other similar applied structural members  100  that can be disposed within the insulating cavity  22  of the structural cabinet  12 . 
     Referring again to  FIGS. 2-4, 6 and 8 , it is contemplated that the wrapper and liner structural reinforcements  34 ,  36  can be defined within the outer wrapper  18  and inner liner  20  themselves. In such an embodiment, both the outer wrapper  18  and the inner liner  20  can visibly reveal the configuration of the various wrapper and liner structural reinforcements  34 ,  36  defined therein. These wrapper and liner structural reinforcements  34   36  can be used as a decorative feature as well as for reinforcing the structural cabinet  12  to resist the inward compressive force  32  generated by the at least partial vacuum  26  in the insulating cavity  22 . 
     Referring again to  FIGS. 1-8 , it is contemplated that the inner liner  20  and outer wrapper  18  can be made of various materials that can be shaped, bent or otherwise formed to include the various wrapper and liner structural reinforcements  34 ,  36  for the structural cabinet  12 . These materials for the outer wrapper  18  and inner liner  20  can include, but are not limited to, metals, plastics, polymers, metal alloys, combinations thereof, and other similar substantially rigid materials that can be used for vacuum insulated structures within appliances  16 . Typically, the inner liner  20  and outer wrapper  18  will be made of a metallic material with the wrapper and liner structural reinforcements  34 ,  36  defined within the material of the outer wrapper  18  and inner liner  20 , respectively. 
     According to various embodiments, it is contemplated that the various distinct reinforcing sections  54  of wrapper and liner structural reinforcements  34 ,  36  can at least partially overlap to create sections of the wrapper and liner structural reinforcements  34 ,  36  that can resist bending, bowing, and other deflection along more than one axis  52 . These overlapping sections of corrugations can form more complex geometries within the outer wrapper  18  and inner liner  20  that can serve to prevent deflection along at least two and potentially three or more axes. Accordingly, by incorporating the structural geometries  50 , the outer wrapper  18  and inner liner  20  can be maintained at a substantially consistent spacing between one another to maintain the insulating cavity  22  at a consistent thickness throughout the structural cabinet  12  of the appliance  16 . 
     Referring again to  FIGS. 1-8 , an insulating structure  10  for an appliance  16  can include first and second members  110 ,  112  that are attached to one another to define an insulating cavity  22  therebetween. The insulating material  24  is disposed within the insulating cavity  22  between the first and second members  110 ,  112 . First structural reinforcements  114  can be disposed proximate the first member  110  and second structural reinforcements  116  can be disposed proximate the second member  112 . It is contemplated that the first and second structural reinforcements  114 ,  116  are free of engagement with one another such that the insulating material  24  extends continuously through the insulating cavity  22 . Stated another way, the first and second structural reinforcements  114 ,  116 , which can correspond to the wrapper and liner structural reinforcements  34 ,  36  in a structural cabinet  12  setting, are continuously spaced apart from one another. By being spaced apart, the first and second structural reinforcements  114 ,  116  do not interrupt or separate portions of the insulating material  24  within the insulating cavity  22 . 
     According to the various embodiments, it is contemplated that the thickness of the first and second structural reinforcements  114 ,  116  can each be within a range of from approximately 1 millimeter to approximately 10 millimeters. It is contemplated that the first and second structural reinforcements  114 ,  116  can be sized to provide for sufficient structural rigidity of the first and second members  112  and also a minimal thickness of the insulating cavity  22  that provides sufficient insulating functions for the insulating structure  10  of the appliance  16 . 
     Referring again to  FIGS. 2-8 , the first and second structural reinforcements  114 ,  116  can be defined by integral undulations  118  that are formed within the first and second members  110 ,  112 . It is contemplated that the first and second structural reinforcements  114 ,  116  are adapted to extend within the insulating cavity  22  and extend toward one another such that the insulating material  24  is shaped to conform to the shape of the integral undulations  118  defined within the first and second members  110 ,  112 . 
     According to various embodiments, as exemplified in  FIGS. 2-4 , where the wrapper and liner structural reinforcements  34 ,  36  are integrally formed within the outer wrapper  18  and inner liner  20 , respectively, and where the first and second structural reinforcements  114 ,  116  are integrally formed within the first and second members  110 ,  112  of the insulating structure  10 , the various structural reinforcements are visible on the exterior  30  of the insulating structure  10 . These various visible patterns generate a structural relief pattern that is visible on the exterior  30  of the insulating structure  10  and/or the structural cabinet  12 . More complex structural relief patterns can be formed where the various ridge sections overlap to form more complex geometries within the inner liner  20 , outer wrapper  18 , and first and second members  110 ,  112 . 
     Referring again to  FIG. 5 , it is contemplated that the first and second structural reinforcements  114 ,  116  can be defined within various reinforcing panels that are disposed proximate the first and second members  110 ,  112  and within the insulating cavity  22 . As discussed above, the use of the wrapper and liner reinforcing panels  90 ,  92  disposed within the insulating cavity  22  serves to allow the exterior  30  of the insulating structure  10  to maintain a smooth and continuous visible appearance. 
     Referring again to  FIGS. 2-4 and 6-8 , the integral undulations  118  defined within the first and second members  110 ,  112  can be oriented to define a plurality of distinct reinforcing or undulating sections within each of the first and second members  110 ,  112 . It is contemplated that each undulating section includes a dedicated axis  52  along which the integral undulations  118  are oriented. The various undulating sections of the first and second members  110 ,  112  can have dedicated axis  52  that are set at various angles within the first and second members  110 ,  112 . In this manner, each of the first and second members  110 ,  112  is adapted to resist the inward compressive force  32  along at least two axis  52 . Additionally, these undulating sections can overlap, such that each dedicated section may define multiple axes  52  along which the inward compressive force  32  can be resisted through the corrugated configuration of the first and second members  110 ,  112  of the insulating structure  10 . 
     As discussed above, the insulating cavity  22  defines an at least partial vacuum  26  that serves to generate an inward compressive force  32  exerted against the first and second members  110 ,  112  and toward the insulating cavity  22 . This inward compressive force  32  is generated through a pressure differential  28  between a normal atmospheric pressure present around the exterior  30  of the insulating structure  10  and the at least partial vacuum  26  present within the insulating cavity  22 . This pressure differential  28  generates the inward compressive force  32  exerted upon the first and second members  110 ,  112  of the insulating structure  10 , similar to that of the inward compressive force  32  exerted against the outer wrapper  18  and inner liner  20  of the structural cabinet  12 . 
     Referring now to  FIGS. 1-9 , having described various aspects of insulating structures  10  that incorporate the structural reinforcements, a method  400  is disclosed for forming a structural cabinet  12  for an appliance  16 . According to the method  400 , a plurality of wrapper structural reinforcements  34  is disposed proximate an outer wrapper  18  (step  402 ). A plurality of liner structural reinforcements  36  is also disposed proximate an inner liner  20  (step  404 ). As discussed above, the wrapper and liner structural reinforcements  34 ,  36  can be integrally formed within the outer wrapper  18  and inner liner  20 , respectively. These wrapper and liner structural reinforcements  34 ,  36  can also be defined within structural reinforcing panels that are disposed within an insulating cavity  22  of the structural cabinet  12 . According to the method  400 , the outer wrapper  18  is attached to the inner liner  20  to define an insulating cavity  22  therebetween (step  406 ). The wrapper and liner structural reinforcements  34 ,  36  are adapted to extend from the outer wrapper  18  and inner liner  20 , respectively, and into the insulating cavity  22 . It is contemplated that the wrapper and liner structural reinforcements  34 ,  36  are free of contact with one another and are spaced apart from one another by a cavity space  130 . 
     Referring again to  FIGS. 1-9 , once the structural cavity is formed through attachment of the inner liner  20  and the outer wrapper  18 , an insulating material  24  is disposed within the insulating cavity  22  (step  408 ). It is contemplated that the insulating material  24  fills or substantially fills the cavity space  130 . In this manner, the insulating material  24  forms a continuous insulating layer that extends between the wrapper and liner structural reinforcements  34 ,  36 . Because the wrapper and liner structural reinforcements  34 ,  36  do not touch one another, these features do not interrupt, separate, or otherwise segregate portions of the insulating material  24 . This configuration can serve to limit thermal transfer between interior portions of the inner liner  20  and the outer wrapper  18 . Once the insulating material  24  is disposed within the cavity space  130 , gas  132  can be expressed and/or expelled from the insulating cavity  22  to define an at least partial vacuum  26  within the insulating cavity  22  (step  410 ). As discussed above, the at least partial vacuum  26  generates the inward compressive force  32  that is exerted against the inner liner  20  and the outer wrapper  18  and is exerted toward the insulating cavity  22 . This inward compressive force  32  serves to bias the inner liner  20  and outer wrapper  18  toward the insulating cavity  22  such that the inner liner  20  and outer wrapper  18  tends to bow inward as a result of the inward compressive force  32  which could result in thinning of the structural walls  60  of the insulating structure  10 , and a decrease in thermal performance. The use of the wrapper and liner structural reinforcements  34 ,  36  serves to oppose this inward compressive force  32  and opposes the tendency of the inner liner  20  and outer wrapper  18  to bow. As a result, the inner liner  20  and outer wrapper  18  are maintained a substantially consistent distance from one another to maintain a substantially consistent undulating thickness of the insulating cavity  22 . 
     After expressing and/or expelling gas  132  from the insulating cavity  22 , the insulating cavity  22  is sealed (step  412 ). The wrapper and liner structural reinforcements  34 ,  36  are positioned to oppose the inward compressive force  32  and maintain the outer wrapper  18  and the inner liner  20  at the substantially consistent distance. This substantially consistent distance serves to maintain the volume of the cavity space  130  between the wrapper and liner structural reinforcements  34 ,  36  to be substantially the same as that volume when the outer wrapper  18  and inner liner  20  were attached such as at step  406  of the method  400 . 
     According to the various embodiments, the method  400  for forming the structural cabinet  12  can also be used for forming an insulating structure  10 , such as an insulating panel  14 , a structural cabinet  12 , or other similar insulating member. These various insulating members can be used in various appliances  16  that can include, but are not limited to, refrigerators, freezers, coolers, ovens, dishwashers, laundry appliances, water heaters, and other similar appliances and fixtures within household and commercial settings. 
     It will be understood by one having ordinary skill in the art that construction of the described device and other components is not limited to any specific material. Other exemplary embodiments of the device disclosed herein may be formed from a wide variety of materials, unless described otherwise herein. 
     For purposes of this disclosure, the term “coupled” (in all of its forms, couple, coupling, coupled, etc.) generally means the joining of two components (electrical or mechanical) directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally formed as a single unitary body with one another or with the two components. Such joining may be permanent in nature or may be removable or releasable in nature unless otherwise stated. 
     It is also important to note that the construction and arrangement of the elements of the device as shown in the exemplary embodiments is illustrative only. Although only a few embodiments of the present innovations have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of the interfaces may be reversed or otherwise varied, the length or width of the structures and/or members or connector or other elements of the system may be varied, the nature or number of adjustment positions provided between the elements may be varied. It should be noted that the elements and/or assemblies of the system may be constructed from any of a wide variety of materials that provide sufficient strength or durability, in any of a wide variety of colors, textures, and combinations. Accordingly, all such modifications are intended to be included within the scope of the present innovations. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the desired and other exemplary embodiments without departing from the spirit of the present innovations. 
     It will be understood that any described processes or steps within described processes may be combined with other disclosed processes or steps to form structures within the scope of the present device. The exemplary structures and processes disclosed herein are for illustrative purposes and are not to be construed as limiting. 
     It is also to be understood that variations and modifications can be made on the aforementioned structures and methods without departing from the concepts of the present device, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise. 
     The above description is considered that of the illustrated embodiments only. Modifications of the device will occur to those skilled in the art and to those who make or use the device. Therefore, it is understood that the embodiments shown in the drawings and described above is merely for illustrative purposes and not intended to limit the scope of the device, which is defined by the following claims as interpreted according to the principles of patent law, including the Doctrine of Equivalents.