Patent Publication Number: US-2023160202-A1

Title: Pre-glazed window wall system

Description:
BACKGROUND 
     Window walls are window systems commonly used in residential and commercial buildings, e.g., in storefronts and on the façade of high-rise buildings. Window walls typically span between floors of a building, from a top of a bottom floor slab to the underside of an above floor slab. Sill and head receptors are installed using anchors and shims to accurately set the receptors parallel to one another on the same plane and at the proper height. Once the sill and head receptors are properly installed, a series of unitized window panels or pre-glazed units can be received by the sill and head receptors and secured thereto to progressively build the window wall. 
     It is always desirable to introduce systems and installation methods that reduce costs and ease the installation process for window walls. 
     SUMMARY OF THE DISCLOSURE 
     Embodiments disclosed herein include a window wall system that includes a sill receptor secured to an upper surface of a first floor slab, the sill receptor providing a base and an upright member extending from the base, a head receptor secured to a bottom surface of a second floor slab vertically offset from the first floor slab, and a glazing unit providing a sill, a head, and one or more panels extending between the sill and the head. A first hook is defined by the sill and engageable with the upright member, wherein, when the upright member is received by the hook, the glazing unit is pivotable about the upright member toward a vertical orientation, and a second hook is defined by the sill and receivable within a groove defined in the sill receptor when the glazing unit reaches the vertical orientation. In a further embodiment of the window wall system, the upright member extends perpendicular from the base. In another further embodiment, the first hook extends downward and thereby defines a downwardly-opening channel sized to receive the upright member. In another further embodiment, wherein receiving the upright member in the channel prevents the glazing unit from migrating toward an exterior or interior environment. In another further embodiment, the window wall system further comprises a spring clip operable to prevent the head from exiting the head receptor once the head is received within the head receptor and the glazing unit reaches the vertical orientation. In another further embodiment, the spring clip is mounted to the head. In another further embodiment, the spring clip is mounted to the head receptor. In another further embodiment, the spring clip provides a spring-loaded biasing member configured to locate a pocket when the glazing unit reaches the vertical orientation, and wherein the spring-loaded biasing member engages an obstruction within the pocket that prevent the head from exiting the head receptor. 
     Embodiments disclosed herein may further include a method of installing a glazing unit of a window wall system, the method including the steps of securing a sill receptor to an upper surface of a first floor slab, the sill receptor providing a base and an upright member extending from the base, securing a head receptor secured to a bottom surface of a second floor slab vertically offset from the first floor slab, receiving the glazing unit between the first and second floor slabs, the glazing unit including a sill, a head, and one or more panels extending between the sill and the head, engaging a first hook defined by the sill with the upright member, and pivoting the glazing unit about the upright member and toward a vertical orientation, and receiving a second hook defined by the sill within a groove defined in the sill receptor when the glazing unit reaches the vertical orientation. In a further embodiment, the first hook extends downward and thereby defines a downwardly-opening channel sized to receive the upright member, and wherein engaging the first hoot with the upright member comprises receiving the upright member in the channel and thereby preventing the glazing unit from migrating toward an exterior or interior environment. In another further embodiment, the method further comprises preventing uplift of the glazing unit by receiving the second hook within the groove. In another further embodiment, the method further comprises securing the glazing unit to the sill receptor without mechanical fasteners. In another further embodiment, pivoting the glazing unit toward the vertical orientation further comprises locating a spring-loaded biasing member of a spring clip in a pocket once when the glazing unit reaches the vertical orientation, and engaging the spring-loaded biasing member against an obstruction within the pocket and thereby preventing the head from exiting the head receptor. 
     Embodiments disclosed herein may also include a window wall system that includes a first glazing unit arranged adjacent a first vertical wall substrate, a second glazing unit arranged adjacent a second vertical wall substrate opposite the first vertical wall substrate, one or more third glazing units extending laterally between the first and second glazing units, and a jamb filler operatively coupled to the second glazing unit and interposing the second glazing unit and the second vertical wall substrate. In a further embodiment, the jamb filler is operatively coupled to the second gazing unit via one or more mating features and without mechanical fasteners. In another further embodiment, the window wall system further comprises one or more backer rods interposing the jamb filler and the second vertical wall substrate. In another further embodiment, one or more third glazing units include a left glazing unit that includes a right vertical mullion half, and a right glazing unit that includes a left vertical mullion half, wherein the left and right glazing units are secured together by mating the right and left vertical mullion halves. In another further embodiment, wherein the right and left vertical mullion halves are mated by shifting the right glazing unit toward the left glazing unit until the left vertical mullion half locates and mates to the right mullion half. In another further embodiment, the right and left vertical mullion halves are mated via a snap-in engagement. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following figures are included to illustrate certain aspects of the present disclosure, and should not be viewed as exclusive embodiments. The subject matter disclosed is capable of considerable modifications, alterations, combinations, and equivalents in form and function, without departing from the scope of this disclosure. 
         FIG.  1    is a schematic front view of an example window wall system  100  that may incorporate the principles of the present disclosure. 
         FIG.  2    is cross-sectional side view of a portion of the window wall system of  FIG.  1   , as taken along the lines  2 - 2  in  FIG.  1   , according to one or more embodiments of the present disclosure. 
         FIG.  3    is a cross-sectional top view of a portion of the system of  FIG.  1   , according to one or more embodiments. 
         FIG.  4    is a cross-sectional top view of another portion of the system of  FIG.  1   , according to one or more additional embodiments. 
         FIG.  5    is a cross-sectional top view of another portion of the system of  FIG.  1   , according to one or more additional embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure is related to window wall systems and, more particularly, to window wall systems with glazing units that are vertically pivotable to install. The glazing units can be pre-glazed and installed using a unique sill-to-sill flashing interlocking engagement at the sill, temporary spring clips at the head and a mullion filler at the last bay jamb. After a sill flashing and a head receptor are installed into the rough opening, the glazing units are installed entirely from the interior of the building by tilting the top of the glazing unit inward and into the building, engaging the sill flashing, and tilting (pivoting) the top back to vertical as engaged to the sill flashing. By tilting only in the horizontal plane, the glazing units are installed straight into the opening, thus eliminating any need for tilting units while they are outside of the opening beyond the slab edge. Engagement and retention of the sill in the sill flashing is provided by the profile geometry which uses a primary hook for alignment and a secondary hook for engagement, which eliminate the typical need for sill-to-sill flashing fasteners. Retention at the head can be provided by a spring clip. After tilting (pivoting) each pre-glazed unit upright into the opening, they can be slid sideways to engage the previously installed unit. 
       FIG.  1    is a schematic front view of an example window wall system  100  that may incorporate the principles of the present disclosure. The window wall system  100  (hereafter “the system  100 ”) may be suitable for installation in large commercial buildings, such as a skyscrapers, but could alternatively be applied to smaller commercial or residential buildings, without departing from the scope of the disclosure. The system  100  includes an assembly of a plurality of shop-assembled glazing units, shown in  FIG.  1    as glazing units  102   a ,  102   b ,  102   c , and  102   d . The glazing units  102   a - d  are arranged between upper and lower floor slabs (not visible), which are covered with a decorative slab edge cover  104 . 
     Each glazing unit  102   a - d  may be substantially similar in construction. However, for purposes of discussion, the second glazing unit  102   b  will be described in further detail below, but discussion of the second glazing unit  102   b  is equally applicable to the other glazing units  102   a,c,d.    
     As illustrated, the glazing unit  102   b  includes a sill  106 , a head  108 , and a pair of laterally spaced mullions  110  extending vertically between the sill  106 , and the head  108 . The sill  106 , the head  108 , and the vertical mullions  110  may each comprise a rigid extrusion made of aluminum, an aluminum alloy, or other metals and metal alloys. The combination of the sill,  106 , the head  108 , and the vertical mullions  110  cooperatively encompass and secure a panel  112  on all four sides to form a solid structure. The panel  112  may comprise, for example, a pane of window glass, polycarbonate, or another clear, translucent, tinted, or opaque material. 
       FIG.  2    is cross-sectional side view of a portion of the window wall system  100 , as taken along the lines  2 - 2  in  FIG.  1   , according to one or more embodiments of the present disclosure. As illustrated, the system  100  may be installed between a first or “lower” floor slab  202   a  and a second or “upper” floor slab  202   b , where the floor slabs  202   a,b  are vertically spaced from each other and generally parallel to accommodate the system  100 . As illustrated, the system  100  includes a sill receptor  204  and a head receptor  206 . The sill receptor  204 , alternately referred to as a “sill flashing,” is secured to the upper surface of the lower floor slab  202   a , and the head receptor  206  is secured to the bottom surface of the upper floor slab  202   b.    
     One or more shims  208  may be inserted between the sill and head receptors  204 ,  206  and the vertically adjacent lower and upper slabs  202   a,b , respectively, to adjust the receptors  204 ,  206  to a proper level. A weather seal caulk may be applied to both the exterior and interior sides of the receptors  204 ,  206  to seal any gaps between the slabs  202   a,b  and the corresponding receptors  204 ,  206  from air and water infiltration. Once properly shimmed, the sill and head receptors  204 ,  206  may be fixed to the lower and upper slabs  202   a,b , respectively, using one or more mechanical fasteners (not shown). 
     The system  100  also includes a glazing unit, such as the second glazing unit  102   b  discussed above. The glazing unit  102   b  may be fabricated, assembled and pre-glazed prior to being transported to the site of the system  100 , and may be configured to be installed between the sill and head receptors  204 ,  206 . As described above, the glazing unit  102   b  includes the sill  106 , the head  108 , and one or more panels  112  extending between the sill  106  and the head  108 . While not shown in  FIG.  2   , the glazing unit  102   b  further includes the pair of laterally-spaced vertical mullions  110  ( FIG.  1   ) that also extend between the sill  106  and the head  108 . 
     In the illustrated embodiment, the glazing unit  102   b  includes two panels  112  separated by a gap that may be filled with air, an inert gas, and/or a coating to control transmission of thermal energy by conduction, radiation and convection between the interior of the building and the exterior environment. In other embodiments, however, the glazing unit  102   b  may have more or less than two panels  112 , without departing from the scope of the disclosure. 
     Once the sill and head receptors  204 ,  206  are properly shimmed and installed, the glazing unit  102   b  may be installed from the interior of the building by tilting the top of the glazing unit  102   b  (e.g., the head  108 ) toward the interior of the building, as indicated by the arrow A, and receiving the sill  106  at the sill receptor  204 . As illustrated, the sill receptor  204  provides or otherwise defines a base  210  and an upright member  212  (alternately referred to as an “upturned leg”) that extends from the base  210 . When the sill receptor  204  is installed on the lower slab  202   b , the base  210  lies substantially horizontal, and the upright member  212  extends substantially vertical from the base  210 . In some embodiments, the upright member  212  may extend perpendicular (e.g., 90°) or close to perpendicular from the base  210 , but may alternatively extend vertically from the base  210  at an angle greater or less than 90°, without departing from the scope of the disclosure. 
     In at least one embodiment, as illustrated, a gasket  214  may interpose the upright member  212  and a portion of the sill  106  to generate a sealed interface at that location. In some embodiments, the gasket  214  may be carried by the upright member  212 , but may alternatively be carried by the sill  106 . In yet other embodiments, the gasket  214  may be independent of either of the upright member  212  or the sill  106 , and in such embodiments the gasket  214  may simply provide a sealed interface between the upright member  212  and the sill  106 . 
     The sill  106  may provide or otherwise define a first or “primary” hook  216  and a second or “secondary” hook  218 . The primary hook  216  may be configured to mate with the upright member  212  as the sill  106  is brought into engagement with the sill receptor  204 . More specifically, the primary hook  216  extends downward and thereby defines a downwardly-opening channel sized to receive an upper end  220  of the upright member  212 . Once the upright member  212  is received within the primary hook  216 , the glazing unit  102   b  may be able to pivot on the upright member  212 , and the top of the glazing unit  102   b  (e.g., the head  108 ) may be tilted back toward the exterior of the building, as indicated by the arrow B. As the glazing unit  102   b  tilts toward the exterior in the direction B, the secondary hook  218  may be received within a groove  222  defined in the sill receptor  204 . In some embodiments, as illustrated, the groove  222  may extend substantially parallel to the base  210 . 
     The primary and secondary hooks  216 ,  218  may prove advantageous in securing the glazing unit  102   b  to the sill receptor  204  without the use of mechanical fasteners (e.g., conventional sill-to-sill flashing fasteners). More specifically, the primary hook  216  facilitates pivoting of the glazing unit  102   b  to a vertical position, but also serves as a safety feature that prevents the glazing unit  102   b  from migrating (slipping) toward the exterior of the building during installation and provides resistance to positive and negative design wind loads after installation. Moreover, the secondary hook  218  received within the groove  222  may prove advantageous in preventing uplift (e.g., moving vertically upward) of the glazing unit  102   b  during heavy wind loads. Consequently, receiving the secondary hook  218  within the groove  222  obviates the need for using a mechanical fastener to prevent uplift. 
     As the glazing unit  102   b  tilts toward the exterior in the direction B, the head  108  is eventually received by the head receptor  206 . In some embodiments, the glazing unit  102   b  may further include a spring clip  224  mounted to or otherwise received by the head  108 . The spring clip  224  may provide or define a spring-loaded biasing member  226 . As the head  108  is received at the head receptor  206  moving in the direction B, the biasing member  226  may engage and ratchet against various internal features  228  of the head receptor  206 . Once the glazing unit  102   b  reaches a substantially vertical orientation, however, the biasing member  226  may locate or otherwise be received into a channel or pocket  230  defined by the head receptor  206 . As it enters the pocket  230 , the biasing member  226  may naturally spring outward and thereby lock the head  108  in place with the head receptor  206 . With the biasing member  226  biased (extended) outward, the head  108  is unable to reverse course in the direction A, thus securing the glazing unit  102   b  in its vertical orientation. 
     As will be appreciated, the spring clip  224  could alternatively be mounted to the head receptor  206 , without departing from the scope of the disclosure. In such embodiments, the biasing member  226  may instead interact with features of the head  108  to prevent the glazing unit  102   b  from departing from its vertical orientation. Once the glazing unit  102   b  is oriented substantially vertical it can be shifted laterally to engage a previously installed glazing unit (not shown). 
     Once the glazing unit  102   b  is oriented substantially vertical, a head receptor face plate  232  may be secured to the head receptor  206  to fully secure the glazing unit  102   b  within the system  100 . In at least one embodiment, as illustrated, the head receptor face plate  232  may be configured for a snap-in engagement to the head receptor  206 . In such embodiments, for example, the head receptor  206  and the head receptor face plate  232  may provide opposing hook features  234  that interlock to secure the head receptor face plate  232  to the head receptor  206 . 
     Moreover, in such embodiments, a gasket  236  may be arranged at the interface between the head receptor face plate  232  and the head  108 . The gasket  236  may be arranged in the interior of the building and, as illustrated, may be carried on the head receptor face plate  232 , but could alternatively be carried on the head  108  or may otherwise be independent of either structure. Another gasket  238  may be arranged at the interface between the head receptor  206  and the head  108 . The gasket  238  may be arranged at the exterior of the building and, as illustrated, may be carried on the head receptor  206 , but could alternatively be carried on the head  108  or may otherwise be independent of either structure. 
     In some embodiments, the system  100  may further include an interior sill cover  240  that is mounted to one or both of the sill receptor  204  and the sill  106 . In the illustrated embodiment, the interior sill cover  240  may provide a snap-in engagement with one or more corresponding features on one or both of the sill receptor  204  and the sill  106 . The interior sill cover  240  may provide an aesthetic feature that conceals the primary hook  216  and the upright member  212 . 
     The glazing unit  102   b  may be installed entirely from the interior of the building by first tilting the top of the glazing unit  102   b  toward the interior, in the direction A, and then tilting back to vertical in the direction B, as generally described above. This is in contrast to conventional window wall installation, which typically requires glazing units to be installed from the exterior of the building and/or angling the glazing unit about a vertical axis. Moreover, the interlocking sill  104  and the sill receptor  204 , combined with the spring clip  224  at the head  108 , may prove advantageous in allowing for quick and easy installation of pre-glazed units without the need for mechanical fasteners. 
       FIG.  3    is a cross-sectional top view of a portion of the system  100  of  FIG.  1   , according to one or more embodiments. In the illustrated embodiment, a glazing unit  300 , similar in some respects to the glazing unit  102   b  of  FIG.  2   , may be arranged adjacent a vertical wall substrate  302 . The system  100  may be constructed starting from the vertical wall substrate  302  and progressively installed toward the right in  FIG.  3   . Accordingly, the vertical wall substrate  302  may be referred to as the “left” vertical wall substrate  302 . And because it is to be positioned adjacent the left vertical wall substrate  302 , the glazing unit  300  may be referred to as the “first bay” glazing unit and all subsequent glazing units will be progressively added to the right in  FIG.  3    by laterally abutting up against the previously installed glazing unit. 
     In alternative embodiments, the vertical wall substrate  302  may be a “right” vertical wall substrate  302 , and the all subsequent glazing units installed after the glazing unit  300  will be progressively added to the left by laterally abutting up against the previously installed glazing unit. 
     As illustrated, the first bay glazing unit  300  may include a vertical jamb member or “mullion”  306  and one or more panels  308  (two shown) are received by and extend from the vertical jamb member  306 . The panels  308  may be similar to the panels  112  of  FIGS.  1  and  2   . In contrast to subsequently installed glazing units, which will include left and right vertical mullion halves, the first bay glazing unit  300  includes the vertical jamb member  306  configured for abutting up against the vertical wall substrate  302 . In some embodiments, one or more backer rods  310  may interpose the vertical jamb member  306  and the adjacent outer surface of the vertical wall substrate  302 . Once the first bay glazing unit  300  is properly positioned, a perimeter sealant  312  may be applied at the gap between the first bay glazing unit  300  and the vertical wall substrate  302  to seal the interface. The vertical backer rods  310  provide a backup surface that prevents the sealant  312  from being deposited into the open interior of the jamb mullion  306 . 
       FIG.  4    is a cross-sectional top view of a portion of the window wall system  100 , as taken along the lines  4 - 4  in  FIG.  1   , according to one or more embodiments of the present disclosure. In the illustrated embodiment, the first and second glazing units  102   a  and  102   b  are arranged side-by-side and otherwise laterally adjacent one another. 
     As illustrated, each glazing unit  102   a,b  includes a vertical mullion half, shown as mullions  110   a  and  110   b , and one or more panels  112  (two shown in each) are received by and extend from each vertical mullion  110   a,b . The vertical mullion half  110   a  for the first glazing unit  102   a  can be referred to as a “right” vertical mullion half  110   a , and the vertical mullion half  110   b  for the second glazing unit  102   b  can be referred to as a “left” vertical mullion half  110   b . In some embodiments, the mullion halves  110   a,b  may alternatively be referred to as “split” mullions since they are designed to interconnect with a laterally adjacent “split” mullion to form a combined vertical mullion. 
     The first glazing unit  102   a  may be installed in the system  100 , as generally described herein with reference to installation of the glazing unit  102   b  of  FIG.  2   . Once the first glazing unit  102   a  is properly installed, the second glazing unit  102   b  may be subsequently installed in the same manner and moved (shifted, slid, etc.) laterally into engagement with the first glazing unit  102   a , as shown in  FIG.  4   . 
     As the second glazing unit  102   b  is moved into lateral engagement with the first glazing unit  102   a  (e.g., to the left in  FIG.  4   ), the left and right mullion halves  110   a,b  may be mated together, thus securing the first glazing unit  102   a  to the second glazing unit  102   b . In some embodiments, for example, the left and right mullion halves  110   a,b  may provide or otherwise define one or more opposing hook features  402  (two shown) configured to mate and interlock to secure the second glazing unit  102   b  to the first glazing unit  102   a . The hook features  402  may comprise, for example, a snap-in or snap-fit engagement between the left and right mullion halves  110   a,b.    
     The two mullion halves  110   a,b  may be designed to provide a positive stop when pushed together laterally without obstructing the continuity of the thermal breaks. Those skilled in the art will readily appreciate that such a feature helps ensure quality control and can be a time saver for an installer. In contrast, when installing conventional glazing units, an installer would typically push the two units together and attempt to stop when the mullion width is at a specific, predetermined dimension. 
       FIG.  5    is a cross-sectional top view of another portion of the system  100  of  FIG.  1   , according to one or more additional embodiments. In the illustrated embodiment, a glazing unit  500  similar in some respects to the glazing unit  102   b  of  FIG.  2    may be arranged adjacent a vertical wall substrate  502 . Installation of the system  100  may terminate at the vertical wall substrate  502 . Accordingly, the vertical wall substrate  502  may be referred to as the “right” vertical wall substrate  502 , and because it is positioned adjacent the right vertical wall substrate  502 , the glazing unit  500  may be referred to as the “last bay” glazing unit in the system  100 . 
     In alternative embodiments, the vertical wall substrate  502  may be a “left” vertical wall substrate  502 , and the glazing units may be installed progressively toward the left until reaching the vertical wall substrate  502  where the last bay glazing unit  500  is installed. 
     As illustrated, the glazing unit  500  may include a vertical jamb member or “mullion”  506  and one or more panels  508  (two shown) are received by and extend from the vertical jamb member  506 . The panels  508  may be similar to the panels  112  of  FIGS.  1  and  2   , and the vertical jamb member  506  may be similar to the vertical jamb member  306  of  FIG.  3   , except that the vertical jamb member  506  is configured for placement laterally adjacent the right vertical wall substrate  502 . 
     Upon installing and mating the last glazing unit  500  with the penultimate glazing unit (not shown) in the system  100 , a gap  510  may remain between the last glazing unit  500  (e.g., the vertical jamb member  506 ) and the right vertical wall substrate  502 . In some embodiments, the system  100  may further include a jamb filler  512  configured to be installed in the system  100  to interpose the last glazing unit  500  and the right vertical wall substrate  502  and thereby fill (extend across) the gap  510 . The jamb filler  512  may be secured and otherwise mated to the glazing unit  500  via one or more mating features  514 , such as opposing hook members or the like. Accordingly, the jamb filler  512  may be secured to the glazing unit  500  without the need for mechanical fasteners, but may instead be secured via a snap-in or snap-fit engagement, or the like. 
     In some embodiments, one or more backer rods  516  may interpose the jamb filler  512  and the adjacent outer surface of the right vertical wall substrate  502 . Once the glazing unit  500  and the jamb filler  512  are properly positioned, a sealant  518  may then be applied at the gap between the jamb filler  512  and the vertical wall substrate  502  to seal the interface. The vertical backer rods  516  provide a backup surface that prevents the sealant  518  from being deposited into the open interior of the jamb filler  512 . 
     Those skilled in the art will readily appreciate the advantages of the jamb filler  512 , which eliminates the need for extra wide jamb shim joints common to conventional window wall systems. Use of the jamb filler  512  is possible since the glazing panels of the system  100  are designed to be installed straight into the opening by tilting the top of the glazing panel toward the interior. In contrast, in conventional window wall systems, the last glazing panel is commonly installed by installing from the outside or pivoting about a vertical axis. In some applications, using the jamb filler  512  may allow the gap between the jamb filler  512  and the right vertical wall substrate  502  to decrease to about ½ inch. 
     Therefore, the disclosed systems and methods are well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular embodiments disclosed above are illustrative only, as the teachings of the present disclosure may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative embodiments disclosed above may be altered, combined, or modified and all such variations are considered within the scope of the present disclosure. The systems and methods illustratively disclosed herein may suitably be practiced in the absence of any element that is not specifically disclosed herein and/or any optional element disclosed herein. While compositions and methods are described in terms of “comprising,” “containing,” or “including” various components or steps, the compositions and methods can also “consist essentially of” or “consist of” the various components and steps. All numbers and ranges disclosed above may vary by some amount. Whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range is specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a-b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the elements that it introduces. If there is any conflict in the usages of a word or term in this specification and one or more patent or other documents that may be incorporated herein by reference, the definitions that are consistent with this specification should be adopted. 
     As used herein, the phrase “at least one of” preceding a series of items, with the terms “and” or “or” to separate any of the items, modifies the list as a whole, rather than each member of the list (i.e., each item). The phrase “at least one of” allows a meaning that includes at least one of any one of the items, and/or at least one of any combination of the items, and/or at least one of each of the items. By way of example, the phrases “at least one of A, B, and C” or “at least one of A, B, or C” each refer to only A, only B, or only C; any combination of A, B, and C; and/or at least one of each of A, B, and C. 
     The use of directional terms such as above, below, upper, lower, upward, downward, left, right, and the like are used in relation to the illustrative embodiments as they are depicted in the figures, the upward direction being toward the top of the corresponding figure and the downward direction being toward the bottom of the corresponding figure.