Patent Publication Number: US-10770840-B1

Title: Shielded electrical connector assembly

Description:
TECHNICAL FIELD OF THE INVENTION 
     The invention generally relates to a shielded electrical connector assembly. 
     BACKGROUND OF THE INVENTION 
     Shielded electrical connector assemblies have been used for numerous automotive applications, such as navigation systems, infotainment systems, air bag systems, and other data transmission systems. Coaxial cables typically consist of an outer shield conductor, an inner center conductor, a dielectric, and an insulation jacket. The outer conductor and the inner conductor of the coaxial cable often electrically interface with a mating coaxial cable through a coaxial connector assembly. 
     Shielded electrical connector assemblies, hereinafter referred to as shielded connectors, are often used to connect coaxial cables while providing a certain degree of electromagnetic shielding. The use of shielded connectors has greatly increased in automotive applications as devices requiring coaxial cable high for speed data communication continue to proliferate. 
     The use of shielded connectors for automotive usage has become so common that standards for signal loss and contact resistance have been devised. Some shielded connectors that meet these specifications use high cost cold drawn tubular shield terminals. 
     Shielded connectors need to have sufficient electrical contact between the mating shield terminals to provide adequate shielding, i.e. improper contacts between the shield terminals can allow significant RF leakage. Thus, shielded connectors use features, such as lances, i.e. cantilevered contacts cut from the shield terminals or copper rings to provide electrical contact between the shield terminals. However, the openings in the shield terminals caused by forming the lances increase RF leakage and the copper rings increase connector insertion force to levels that make assembling the shielded connectors difficult. 
     Therefore, a low cost shielded connector which meets all performance specifications remains desired. 
     The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also be inventions. 
     BRIEF SUMMARY OF THE INVENTION 
     According to one embodiment of the invention, a shielded electrical connector assembly is provided. The shielded electrical connector assembly includes a shield terminal having an attachment portion configured to be connected to a shield conductor of a coaxial cable and a connection portion configured to be received within a mating shield terminal. The shielded electrical connector assembly further includes a contact cage surrounding a forward segment of the connection portion and slideably attached to the shield terminal. The contact cage defines a plurality of arcuate contact arms configured to be in intimate compressive contact with a mating shield terminal inner wall when the shield terminal is inserted within the mating shield terminal. As used herein, forward refers to a direction toward the end of the connection portion that is inserted within the mating shield terminal and rearward refers to a direction that is away from the end of the connection portion that is inserted within the mating shield terminal. The compressive contact of the plurality of arcuate contact arms with the mating shield terminal inner wall causes the contact cage to extend rearwardly when the shield terminal is inserted within the mating shield terminal. 
     In an example embodiment having one or more features of the shielded electrical connector assembly of the previous paragraph, a forward end of the contact cage is fixedly attached to the forward segment and a rearward end of the contact cage is slideably attached. 
     In an example embodiment having one or more features of the shielded electrical connector assembly of the previous paragraph, the forward end of the contact cage is rounded. 
     In an example embodiment having one or more features of the shielded electrical connector assembly of the previous paragraph, the forward end of the contact cage covers a leading edge of the connection portion. 
     In an example embodiment having one or more features of the shielded electrical connector assembly of the previous paragraph, the shielded electrical connector assembly further includes the coaxial cable which has the shield conductor surrounding a central conductor. The shield conductor is connected to the shield terminal. The shielded electrical connector assembly also includes a central conductor terminal disposed within the inner insulator and connected to the central conductor. 
     In an example embodiment having one or more features of the shielded electrical connector assembly of the previous paragraph, the shielded electrical connector assembly further includes an inner insulator disposed within the shield terminal. A side wall of the forward segment defines an inspection aperture configured to allow visual verification of proper seating of the central terminal within the inner insulator and/or shield terminal. 
     According to another embodiment of the invention, a shielded electrical connector assembly is provided. The shielded electrical connector assembly includes a shield terminal formed of a first electrically conductive material having an attachment portion configured to attach to a shield conductor of a coaxial cable and a connection portion configured to be received within a mating shield terminal and a contact cage formed of a second electrically conductive material having a forward band, a rearward band and a plurality of longitudinally arranged arcuate contact arms extending from the forward band to the rearward band. The contact cage is slideably attached to the shield terminal by a tab extending from the forward band that is folded into an opening in the connection portion and by a cantilevered tab extending from a side wall of the connection portion. The cantilevered tab is configured to inhibit forward motion of the rearward band. 
     In an example embodiment having one or more features of the shielded electrical connector assembly of the previous paragraph, the contact cage includes a plurality of tabs extending from the forward band that are folded into the opening in the connection portion. The folded regions of the plurality of tabs have a rounded shape. 
     In an example embodiment having one or more features of the shielded electrical connector assembly of the previous paragraph, the shielded electrical connector assembly further includes an inner insulator disposed within the shield terminal. The side wall of the connection portion defines an inspection aperture. 
     In an example embodiment having one or more features of the shielded electrical connector assembly of the previous paragraph, the plurality of tabs is a first plurality of tabs. The contact cage also includes a second plurality of tabs extending from the forward band that are folded into the inspection aperture. 
     In an example embodiment having one or more features of the shielded electrical connector assembly of the previous paragraph, the contact cage has a generally cylindrical shape. A first gap is defined in the forward band and a second gap is defined in the rearward band. 
     In an example embodiment having one or more features of the shielded electrical connector assembly of the previous paragraph, the first gap is longitudinally aligned with the second gap. 
     According to yet another embodiment of the invention, a method of forming a shielded electrical connector assembly is provided. The method includes the steps of forming a shield terminal formed of a first electrically conductive material having an attachment portion configured to attach to a shield conductor of a coaxial cable and a connection portion configured to be received within a mating shield terminal and forming a contact cage formed of a second electrically conductive material having a forward band, a rearward band, a plurality of longitudinally arranged arcuate contact arms extending from the forward band to the rearward band, and a first plurality of tabs extending from the forward band. 
     In an example embodiment having one or more features of the method of the previous paragraph, the method further includes the steps of cutting a shield terminal preform from a first sheet of electrically conductive material, forming the shield terminal preform into the shield terminal, forming a cantilevered tab extending from a side wall of the connection portion, cutting a contact cage preform from a second sheet of electrically conductive material, forming the contact cage preform into the contact cage, and slideably attaching the contact cage to the shield terminal by folding the first plurality of tabs into an opening in the connection portion and sliding the rearward band past the cantilevered tab. 
     In an example embodiment having one or more features of the method of the previous paragraph, the folded regions of the first plurality of tabs have a rounded shape. 
     In an example embodiment having one or more features of the method of the previous paragraph, the method further includes the step of forming an inspection aperture in the side wall of the connection portion. 
     In an example embodiment having one or more features of the method of the previous paragraph, the contact cage includes a second plurality of tabs extending from the forward band and the method further includes the step of folding the second plurality of tabs into the inspection aperture. 
     In an example embodiment having one or more features of the method of the previous paragraph, the contact cage is formed into a generally cylindrical shape and wherein a first gap is defined in the forward band and a second gap is defined in the rearward band. 
     In an example embodiment having one or more features of the method of the previous paragraph, the first gap is longitudinally aligned with the second gap. 
     In an example embodiment having one or more features of the method of the previous paragraph, compression of the plurality of contact arms causes the contact cage to extend rearwardly. 
     According to one more embodiment of the invention, a method of interconnecting a shielded electrical connector assembly is provided. The method includes the step of providing a shielded electrical connector including a shield terminal having an attachment portion configured to be connected to a shield conductor of a first coaxial cable and a connection portion, the shielded electrical connector further including a contact cage surrounding a forward segment of the connection portion and slideably attached to the shield terminal. The contact cage defines a plurality of arcuate contact arms. The method also includes the steps of providing a mating shielded electrical connector having a mating shield terminal configured to receive the connection portion of the shield terminal and inserting the connection portion of the shield terminal into the mating shield terminal such that the plurality of arcuate contact arms are in intimate compressive contact with a mating shield terminal inner wall. The compressive contact of the plurality of arcuate contact arms with the mating shield terminal inner wall causes the contact cage to extend rearwardly when the shield terminal is inserted within the mating shield terminal. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       The present invention will now be described, by way of example with reference to the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a shielded electrical connector assembly in a connected state according to one embodiment of the invention; 
         FIG. 2  is a perspective view of the shielded electrical connector assembly of  FIG. 1  in a disconnected state according to one embodiment of the invention; 
         FIG. 3  is a side view of a shielded electrical connector of the shielded electrical connector assembly of  FIG. 1  according to one embodiment of the invention; 
         FIG. 4  is a cross section end view of the shielded electrical connector of  FIG. 3  according to one embodiment of the invention; 
         FIG. 5  is an exploded view of the shielded electrical connector of  FIG. 3  according to one embodiment of the invention; 
         FIG. 6  is an isolated perspective view of a shield terminal and a contact cage of the shielded electrical connector of  FIG. 3  according to one embodiment of the invention; 
         FIG. 7  is a perspective view of a shield terminal preform of the shielded electrical connector of  FIG. 3  according to one embodiment of the invention; 
         FIG. 8  is a perspective view of a a contact cage preform of the shielded electrical connector of  FIG. 3  according to one embodiment of the invention; 
         FIG. 9  is a flow chart of a method of forming a shielded electrical connector assembly according to another embodiment of the invention; and 
         FIG. 10  is a flow chart of a method of interconnecting a shielded electrical connector assembly according to yet another embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the various described embodiments. However, it will be apparent to one of ordinary skill in the art that the various described embodiments may be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits, and networks have not been described in detail so as not to unnecessarily obscure aspects of the embodiments. 
       FIGS. 1-6  illustrate a non-limiting example of a shielded electrical connector assembly according to one or more embodiments of the invention. The example shielded electrical connector assembly, hereinafter referred to as the assembly  10 , is used to interconnect coaxial cables, such as those used to transmit high speed digital data.  FIG. 1  shows the assembly  10  in a connected state and  FIG. 2  shows the assembly  10  in a disconnected state. 
     As best shown in  FIG. 2 , the assembly  10  includes a male connector assembly, hereinafter referred to as the male connector  12 , terminating a first coaxial cable  14  and a female connector assembly, hereinafter referred to as the female connector  16 , terminating a second coaxial cable  18 . The male connector  12  includes a male pin terminal (not shown) connected to the center conductor (not shown) of the first coaxial cable  14  and a female shield terminal  20  that longitudinally surrounds the male pin terminal. An attachment portion  22  of the female shield terminal  20  is mechanically and electrically connected a first inner ferrule  24  that is in contact with the shield conductor (not shown) of the first coaxial cable  14 . The first inner ferrule  24  is secured to the first coaxial cable  14  by a first outer ferrule  26 . The first inner ferrule  24  is crimped to the first outer ferrule  26  by a first crimping sleeve that includes crimping wings that attach the first crimping sleeve to the insulative jacket of the first coaxial cable  14 . The male connector  12  also includes a dielectric insulator (not shown) between the male pin terminal and the female shield terminal  20 . 
     As best shown in  FIGS. 2-5 , the female connector  16  includes a female socket terminal  28  connected to the center conductor  30  of the second coaxial cable  18  and a male shield terminal  32  that longitudinally surrounds the female socket terminal  28 . An attachment portion  34  of the male shield terminal  32  is mechanically and electrically connected a second inner ferrule  36  that is in contact with the shield conductor  38  of the second coaxial cable  18 . The second inner ferrule  36  is secured to the second coaxial cable  18  by a second outer ferrule  40 . The second inner ferrule  36  is crimped to the second outer ferrule  40  by a second crimping sleeve that includes crimping wings that attach the second crimping sleeve to the insulative jacket of the second coaxial cable  18 . The female connector  16  also includes a dielectric insulator  42  between the female socket terminal  28  and the male shield terminal  32 . As shown in  FIG. 1 , a connection portion  44  of the male shield terminal  32  of the female connector  16  is configured to be received within the female shield terminal  20  of the male connector  12 . The female connector  16  further includes a contact cage  46  that surrounds a forward segment of the connection portion  44 . The contact cage  46  is slideably attached to the male shield terminal  32 , i.e., although the contact cage  46  is attached to the connection portion  44 , at least a portion of the contact cage  46  is free to move and slide along the contact portion. The contact cage  46  defines a plurality of arcuate contact arms  48  that are configured to be in intimate compressive contact with an inner wall  50  of the female shield terminal  20  when the male shield terminal  32  is inserted within the female shield terminal  20 . The compressive contact of the plurality of arcuate contact arms  48  with the inner wall  50  causes the contact cage  46  to extend rearwardly when the male shield terminal  32  is inserted within the female shield terminal  20 . 
     As used herein, the designation male or female connector is based on the gender of the terminal connected to the center conductor of the coaxial cable to which the connector is attached. In alternative embodiments, the male connector may include a male shield terminal surrounding a male pin terminal and the female connector may have female shield terminal surrounding a female socket terminal. Additionally, in alternative embodiments, the male and/or female contactor may terminate other circuit elements, such as conductive traces on a printed circuit board. 
     Focusing now on the female connector  16  shown in  FIGS. 3-5 , the male shield terminal  32  formed of a first electrically conductive material, such as a plated copper material. The contact cage  46  is formed of a second electrically conductive material, such as 301½ hard tempered stainless steel. The contact cage  46  has a forward band  52 , a rearward band  54  and the plurality of longitudinally arranged arcuate contact arms  48  that extend from the forward band  52  to the rearward band  54 . The forward band  52  of the contact cage  46  is fixedly attached to the male shield terminal  32  by a first plurality of tabs  56  extending from the forward band  52  that is folded into an opening in the connection portion  44  and by a cantilevered tab  58  extending from a side wall  60  of the connection portion  44 . Folded regions  62  of the plurality of tabs  56  have a rounded shape over the forward end of the male shield terminal  32 . The rounded ends of the folded regions  62  provide the benefit of allowing the male shield terminal  32  to be used in a sealed application with a reduced likelihood of tearing a seal as the male shield terminal  32  is inserted through the seal. A rearward edge  64  of the cantilevered tab  58  extends above the outer wall of the connection portion  44  and engages the rearward band  54 . This engagement of the cantilevered tab  58  with the rearward band  54  inhibits forward motion of the contact cage  46  along the connection portion  44  while allowing the rearward band  54  to move in a rearward direction along the connection portion  44  due to compression of the contact arms  48  when the male terminal shield is inserted within the female shield terminal  20 . 
     Alternative embodiments of the assembly may be envisioned in which a single tab extending from the forward band  52  is folded into the opening in the connection portion  44  to attach the contact cage  46  to the male shield terminal. 
     As best shown in  FIG. 6 , the side wall  60  of the connection portion  44  defines an inspection aperture  66  that allows visual inspection for proper placement of the female socket terminal  28  within the dielectric insulator  42  and male shield terminal  32 . Visual inspection of placement of the female socket terminal may be performed manually, e.g. by a human assembly operator, or automatically, e.g. by a machine vision system. 
     As illustrated in  FIG. 6 , the contact cage  46  also has a second plurality of tabs  68  that extend from the forward band  52  that are folded into the inspection aperture  66 . The second plurality of tabs  68  are configured to further hinder forward motion of the contact cage  46  relative to the connection portion  44  once these tabs  68  are folded into the inspection aperture  66 . The second plurality of tabs  68  also inhibit rotational movement of the contact cage  46  around the connection portion  44 . 
     The contact cage  46  has a generally cylindrical shape. A first gap is defined in the forward band  52  and a second gap is defined in the rearward band  54 . The first gap is longitudinally aligned with the second gap. 
     Although the example of the assembly  10  presented herein has a straight, i.e. 180 degree, connection orientation between the first and second coaxial cables, other embodiments of the assembly may be envisioned with different connection orientation between the first and second coaxial cables, particularly a right angle, i.e. 90 degree, connection orientation. 
       FIG. 7  illustrates a method  100  of forming a shielded electrical connector assembly, e.g. the assembly  10  described above. The method  100  includes the following steps: 
     STEP  102 , CUT A SHIELD TERMINAL PREFORM FROM A FIRST SHEET OF ELECTRICALLY CONDUCTIVE MATERIAL, includes cutting a shield terminal preform  70  from a first sheet of electrically conductive material. As used herein, the shield terminal preform  70  is a flat workpiece cut from a sheet of electrically conductive material that has all of the geometric features required to form the shield terminal  32  after application of a forming process such as bending, rolling, stretching, spinning, or deep drawing. The shield terminal preform  70  is attached to a first carrier strip  72  integrally formed from the first sheet of electrically conductive material to facilitate handling of the shield terminal preform  70 ; 
     STEP  104 , FORM THE SHIELD TERMINAL PREFORM INTO A SHIELD TERMINAL HAVING AN ATTACHMENT PORTION CONFIGURED TO ATTACH TO A SHIELD CONDUCTOR OF A COAXIAL CABLE AND A CONNECTION PORTION CONFIGURED TO BE RECEIVED WITHIN A MATING SHIELD TERMINAL, includes forming a shield terminal  32  having an attachment portion  22  configured to attach to a shield conductor  38  of a coaxial cable  18  and a connection portion  44  configured to be received within a mating shield terminal  20 ; 
     STEP  106 , FORM A CANTILEVERED TAB EXTENDING FROM A SIDE WALL OF THE CONNECTION PORTION, includes forming a cantilevered tab  58  extending from a side wall  60  of the connection portion  44 . In the illustrated example, the cantilevered tab  58  is formed prior to STEP  104 ; 
     STEP  108 , CUT A CONTACT CAGE PREFORM FROM A SECOND SHEET OF ELECTRICALLY CONDUCTIVE MATERIAL, includes cutting a contact cage preform  74  from a second sheet of electrically conductive material. As used herein, the contact cage preform  74  is a flat workpiece cut from a sheet of electrically conductive material that has all of the geometric features required to form the contact cage  46  after application of a forming process such as bending, rolling, stretching, spinning, or deep drawing. The contact cage preform  74  is attached to a second carrier strip  76  integrally formed from the second sheet of electrically conductive material to facilitate handling of the contact cage preform  74 ; 
     STEP  110 , FORM THE CONTACT CAGE PREFORM A CONTACT CAGE HAVING A FORWARD BAND, A REARWARD BAND, A PLURALITY OF LONGITUDINALLY ARRANGED ARCUATE CONTACT ARMS EXTENDING FROM THE FORWARD BAND TO THE REARWARD BAND, AND A FIRST PLURALITY OF TABS EXTENDING FROM THE FORWARD BAND, includes forming a contact cage  46  having a forward band  52 , a rearward band  54 , a plurality of longitudinally arranged arcuate contact arms  48  extending from the forward band  52  to the rearward band  54 , and a first plurality of tabs  56  extending from the forward band  52 ; 
     STEP  112 , SLIDEABLY ATTACH THE CONTACT CAGE TO THE SHIELD TERMINAL BY FOLDING THE FIRST PLURALITY OF TABS INTO AN OPENING IN THE CONNECTION PORTION AND SLIDING THE REARWARD BAND PAST THE CANTILEVERED TAB, includes slideably attaching the contact cage  46  to the shield terminal  32  by folding the first plurality of tabs  56  into an opening in the forward end of the connection portion  44  and sliding the rearward band  54  past the cantilevered tab  58 ; 
     STEP  114 , FORM AN INSPECTION APERTURE IN THE SIDE WALL OF THE CONNECTION PORTION, forming an inspection aperture  66  in the side wall  60  of the connection portion  44 . In the illustrated example, the inspection aperture  66  is formed by cutting notches in the edges of the shield terminal preform and bringing the edges together when the shield terminal  32  is formed from the shield terminal preform in STEP  104 ; and 
     STEP  116 , FOLD A SECOND PLURALITY OF TABS INTO THE INSPECTION APERTURE, includes folding the second plurality of tabs  68  into the inspection aperture  66  when the contact cage  46  includes a second plurality of tabs  68  extending from the forward band  52 . 
       FIG. 8  illustrates a method  200  of interconnecting a shielded electrical connector assembly, e.g. the assembly  10  described above. The method  200  includes the following steps: 
     STEP  202 , PROVIDE A SHIELDED ELECTRICAL CONNECTOR INCLUDING A SHIELD TERMINAL HAVING AN ATTACHMENT PORTION CONFIGURED TO BE CONNECTED TO A SHIELD CONDUCTOR OF A FIRST COAXIAL CABLE AND A CONNECTION PORTION, THE SHIELDED ELECTRICAL CONNECTOR FURTHER INCLUDING A CONTACT CAGE SURROUNDING A FORWARD SEGMENT OF THE CONNECTION PORTION AND SLIDEABLY ATTACHED TO THE SHIELD TERMINAL, WHEREIN THE CONTACT CAGE DEFINES A PLURALITY OF ARCUATE CONTACT ARMS, includes providing a shielded electrical connector  16  including a shield terminal  32  having an attachment portion  22  configured to be connected to a shield conductor  38  of a first coaxial cable  14  and a connection portion  44 . The shielded electrical connector  16  further includes a contact cage  46  surrounding a forward segment of the connection portion  44  and slideably attached to the shield terminal  32 . The contact cage  46  defines a plurality of arcuate contact arms  48 ; 
     STEP  204 , PROVIDE A MATING SHIELDED ELECTRICAL CONNECTOR HAVING A MATING SHIELD TERMINAL CONFIGURED TO RECEIVE THE CONNECTION PORTION OF THE SHIELD TERMINAL, includes providing a mating shielded electrical connector  12  having a mating shield terminal  20  configured to receive the connection portion  44  of the shield terminal  32 ; and 
     STEP  206 , INSERT THE CONNECTION PORTION OF THE SHIELD TERMINAL INTO THE MATING SHIELD TERMINAL SUCH THAT THE PLURALITY OF ARCUATE CONTACT ARMS ARE IN INTIMATE COMPRESSIVE CONTACT WITH A MATING SHIELD TERMINAL INNER WALL, WHEREIN THE COMPRESSIVE CONTACT OF THE PLURALITY OF ARCUATE CONTACT ARMS WITH THE MATING SHIELD TERMINAL INNER WALL CAUSES THE CONTACT CAGE TO EXTEND REARWARDLY WHEN THE SHIELD TERMINAL IS INSERTED WITHIN THE MATING SHIELD TERMINAL, includes inserting the connection portion  44  of the shield terminal  32  into the mating shield terminal  20  such that the plurality of arcuate contact arms  48  are in intimate compressive contact with a mating shield terminal inner wall  50 . The compressive contact of the plurality of arcuate contact arms  48  with the inner wall  50  of the mating shield terminal  20  causes the contact cage  46  to extend rearwardly when the shield terminal  32  is inserted within the mating shield terminal  20 . 
     Accordingly, a shielded electrical connector assembly  10 , a method  100  of forming a shielded electrical connector assembly  10 , and a method  200  of interconnecting a shielded electrical connector assembly  10  is presented. The assembly  10  and methods  100 ,  100  provide the benefit of reduced engagement force required to mate the male connector  12  with the female connector  16  due to the stainless steel contact cage design. The contact cage  46  is held in place by multiple folded tabs  56  that prevent movement of the contact cage  46  in all directions except for the rearward band  54  which moves horizontally as the contact arms  48  are depressed by contacting the inner wall  50  of the female shield terminal  20 . This rearward movement of the rearward band  54  provides a balance between engagement force and contact force during the assembly process. The low permanent set of the stainless steel material forming the contact cage  46  allows the contact arms  48  to be depressed multiple times without deformation. Openings in the male shield terminal  32  are minimal, so radio frequency interference performance is optimized. An inspection aperture  66  in the male shield terminal  32  makes the inner insulator visible to reduce the likelihood that an improperly inserted inner insulator and inner terminal will be undetected. The folded tabs  56  on the leading edge of the female connector  16  allow it to be inserted through seals without tearing the seal. 
     While this invention has been described in terms of the preferred embodiments thereof, it is not intended to be so limited, but rather only to the extent set forth in the claims that follow. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to configure a particular situation or material to the teachings of the invention without departing from its scope. Dimensions, types of materials, orientations of the various components, and the number and positions of the various components described herein are intended to define parameters of certain embodiments, and are by no means limiting and are merely prototypical embodiments. 
     Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the following claims, along with the full scope of equivalents to which such claims are entitled. 
     As used herein, ‘one or more’ includes a function being performed by one element, a function being performed by more than one element, e.g., in a distributed fashion, several functions being performed by one element, several functions being performed by several elements, or any combination of the above. 
     It will also be understood that, although the terms first, second, etc. are, in some instances, used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first contact could be termed a second contact, and, similarly, a second contact could be termed a first contact, without departing from the scope of the various described embodiments. The first contact and the second contact are both contacts, but they are not the same contact. 
     The terminology used in the description of the various described embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various described embodiments and the appended claims, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms “includes,” “including,” “comprises,” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     As used herein, the term “if” is, optionally, construed to mean “when” or “upon” or “in response to determining” or “in response to detecting,” depending on the context. Similarly, the phrase “if it is determined” or “if [a stated condition or event] is detected” is, optionally, construed to mean “upon determining” or “in response to determining” or “upon detecting [the stated condition or event]” or “in response to detecting [the stated condition or event],” depending on the context. 
     Additionally, while terms of ordinance or orientation may be used herein these elements should not be limited by these terms. All terms of ordinance or orientation, unless stated otherwise, are used for purposes distinguishing one element from another, and do not denote any particular order, order of operations, direction or orientation unless stated otherwise.