Patent Publication Number: US-8123534-B1

Title: Mounting features for straddle mount connectors

Description:
BACKGROUND OF THE INVENTION 
     The subject matter herein relates generally to circuit board connectors, and more particularly to mounting features for straddle mount connectors that are mounted to an edge of a circuit board. 
     One type of electrical connector used in today&#39;s electronic equipment is termed a “straddle mount connector” or “board edge connector”. The electrical connector is provided for receiving a circuit board having a mating edge and a plurality of contact pads or conductors exposed adjacent the mating edge of the board. Typically, the electrical connector includes contacts having cantilevered spring arms which are biased against the contact pads on the circuit board. The contacts are soldered to the contact pads after the electrical connector is mounted to the circuit board. The electrical connector includes board mounting features extending outward therefrom that rest on the surface of the circuit board. The board mounting features have an opening therethrough that is aligned with an opening in the circuit board. A separate fastener passes through the opening in the board mounting feature and the circuit board to hold the electrical connector to the circuit board. In some applications, the electrical connector and the attached circuit board form a sub-assembly for a further device. One such use for the electrical connector is in the assembly of making memory cards or other electronic devices. 
     Known electrical connectors are not without disadvantages. For instance, there is a trend to increase the density of electrical connectors and other electronic components on the circuit board. The real estate of the circuit board is valuable. There is a desire to reduce the amount of space the electrical connectors and other electronic components require on the circuit board. Having bulky board mounting features requires additional space along the edge of the circuit board, reducing the total space allowed for mounting electrical connectors or other electronic components to the circuit board. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In one embodiment, a straddle mount connector is provided having a housing that has a mating end and a mounting end configured to be mounted to an edge of a circuit board. The housing has a top and a bottom. The housing has an upper mounting feature extending from the mounting end proximate to the top and a lower mounting feature extending from the mounting end proximate to the bottom. The upper and lower mounting features are configured to extend into an opening through the circuit board to secure the housing to the circuit board. Contacts are held by the housing and extend from the mounting end and are configured to be terminated to both sides of the circuit board. The contacts are arranged at the mating end and are configured for mating with a corresponding mating component. 
     In a further embodiment, a connector system is provided with a circuit board that has a first surface and a second surface with pads on the first and second surfaces proximate to an edge of the circuit board. The edge extends in a longitudinal direction. The pads define a contact region of the circuit board. The circuit board has an opening that extends therethrough. The opening is longitudinally offset from the contact region. A straddle mount connector is mounted to the edge of the circuit board. The straddle mount connector has a housing having a mating end and a mounting end configured to be mounted to the edge of the circuit board. The housing is elongated in a longitudinal direction parallel to the mounting end and has a mounting feature that extends from the mounting end. The mounting feature is configured to extend into the opening through the circuit board to secure the housing to the circuit board. The mounting feature has a side that defines the longitudinally outermost portion of the straddle mount connector. The side is positioned inside of a longitudinally outermost point of the opening. Contacts are held by the housing and extend from the mounting end and are configured to be terminated to pads on both sides of the circuit board. The contacts are arranged at the mating end and are configured for mating with a corresponding mating component. 
     In another embodiment, a connector system is provided having a circuit board that has a first surface and a second surface with pads on the first and second surfaces proximate to an edge of the circuit board. The pads define a contact region of the circuit board. The circuit board has an opening extending therethrough. The opening has a centerline dividing the opening into an outer portion and an inner portion. The inner portion is positioned between the outer portion and the contact region. A straddle mount connector is mounted to the edge of the circuit board and includes a housing that has a mating end and a mounting end configured to be mounted to the edge of a circuit board. The housing has a mounting feature extending from the mounting end. The mounting feature is configured to extend into the inner portion of the opening through the circuit board to secure the housing to the circuit board. Contacts are held by the housing and extend from the mounting end and are configured to be terminated to pads on both sides of the circuit board. The contacts are arranged at the mating end and are configured for mating with a corresponding mating component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a bottom, front perspective view of a connector system formed in accordance with an exemplary embodiment showing a straddle mount connector mounted to a circuit board. 
         FIG. 2  is a top, rear perspective view of the connector system shown in  FIG. 1 . 
         FIG. 3  is a top view of the straddle mount connector mounted to the circuit board. 
         FIG. 4  is a bottom view of a portion of the straddle mount connector and the circuit board. 
         FIG. 4A  is a bottom view of a portion of straddle mount connectors and the circuit board. 
         FIG. 5  is a cross-sectional view of the straddle mount connector mounted to the circuit board. 
         FIG. 5A  is a cross-sectional view of the straddle mount connector mounted to the circuit board. 
         FIG. 6  illustrates an alternative straddle mount connector formed in accordance with an alternative embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is a bottom, rear perspective view of a connector system  100  formed in accordance with an exemplary embodiment showing a straddle mount connector  102  mounted to a circuit board  104 .  FIG. 2  is a top, rear perspective view of the connector system  100 . Electrical components (not shown), such as memory modules, processors and the like may also be mounted to the circuit board  104 . Optionally, more than one straddle mount connector  102  may be mounted to the circuit board  104 . 
     The circuit board  104  includes a first surface  106  and a second surface  108 . The circuit board  104  has a mating edge  110  with a plurality of contact pads  112  on the first and second surfaces  106 ,  108  at the mating edge  110 . The mating edge  110  extends longitudinally along a longitudinal axis  114 . The contact pads  112  are arranged in a contact region  116  defined between openings  118  of the circuit board  104 . The openings  118  define mounting features of the circuit board  104 . The straddle mount connector  102  is mounted to the mating edge  110  of the circuit board  104  at the contact region  116  such that the straddle mount connector  102  is electrically connected to the contact pads  112 . The contact pads  112  may be any type of pads, such as power pads, signal pads, ground pads and the like, where power is transmitted through the power pads, data signals are transmitted through the signal pads, and the ground pads are electrically commoned with a ground plane of the circuit board  104 . 
     The straddle mount connector  102  engages the openings  118  for securely coupling the straddle mount connector  102  to the circuit board  104 . In the illustrated embodiment, the openings  118  are circular, however the openings  118  may have other shapes in alternative embodiments. As described in further detail below, portions of the straddle mount connector  102  are received in the openings  118  to secure the straddle mount connector  102  to the circuit board  104 . 
     The straddle mount connector  102  includes a housing  120  having a mating end  122  and a mounting end  124  opposite the mating end  122 . The mating end  122  is configured for mating with a corresponding mating component  125 . In the illustrated embodiment, the mating end  122  includes a slot  126  that is configured to receive a circuit card therein. The circuit card represents one type of mating component that may be used with the straddle mount connector  102 . The circuit card may include contact pads proximate to an edge of the circuit card, where the edge is received in the slot  126 . Other types of mating components may be used in alternative embodiments, such as a mating connector. The mating end  122  of the straddle mount connector  102  may be shaped differently for mating with different types of mating components. 
     The straddle mount connector  102  includes a plurality of power contacts  128  and a plurality of signal contacts  130 . The straddle mount connector  102  may include other types of contacts in alternative embodiments, such as ground contacts. The straddle mount connector  102  may include only power contacts  128  or only signal contacts  130  in alternative embodiments. The power contacts  128  and signal contacts  130  are aligned with corresponding contact pads  112  in the contact region  116  when the straddle mount connector  102  is mounted to the circuit board  104 . 
     The power contacts  128  and signal contacts  130  are held by the housing  120 . The power contacts  128  and the signal contacts  130  extend from the mounting end  124  of the housing  120  for terminating to the contact pads  112  on the circuit board  104 . The power contacts  128  and signal contacts  130  are cantilevered beyond the mounting end  124 . In an exemplary embodiment, the power contacts  128  and the signal contacts  130  are soldered to the contact pads  112  to electrically and mechanically couple the power contacts  128  and signal contacts  130  to the contact pads  112 . 
     The power contacts  128  and signal contacts  130  extend through the housing  120  and are arranged at the mating end  122  of the housing  120  for mating with the mating component. For example, ends of the power contacts  128  and signal contacts  130  are exposed within the slot  126  for mating with the circuit card when the circuit card is plugged into the slot  126 . The housing  120  surrounds the power contacts  128  and the signal contacts  130  at mating ends thereof. 
     The housing  120  includes a top  132  and a bottom  134  opposite the top  132 . The housing  120  extends between opposite left and right sides  136 ,  138 . The housing  120  is elongated longitudinally between the left and right sides  136 ,  138  along a longitudinal axis  140 . The longitudinal axis  140  extends along the longitudinal axis  114  of the mating edge  110  of the circuit board  104 . 
     In an exemplary embodiment, the power contacts  128  and signal contacts  130  are arranged in both an upper row and a lower row, with the upper row proximate to the top  132  and the lower row proximate to the bottom  134 . The power contacts  128  and the signal contacts  130  in the upper row engage contact pads  112  on the first surface  106 . The power contacts  128  and the signal contacts  130  in the lower row engage contact pads  112  on the second surface  108 . The power contacts  128  and the signal contacts  130  are also configured to engage contact pads on both an upper surface and a lower surface of the circuit card that is plugged into the slot  126 . The power contacts  128  and signal contacts  130  are arranged along both an upper portion and a lower portion of the slot  126  and define a space therebetween that receives the circuit card between the upper and lower rows of the power contacts  128  and signal contacts  130 . 
     The straddle mount connector  102  includes a plurality of mounting features that are used to secure the straddle mount connector  102  to the circuit board  104 . The mounting features of the straddle mount connector  102  engage the openings  118  of the circuit board  104  to secure the straddle mount connector  102  to the circuit board  104 . 
     In the illustrated embodiment, the straddle mount connector  102  includes a left side upper mounting feature  142 , a left side lower mounting feature  144 , a right side upper mounting feature  146  and a right side lower mounting feature  148 . Any number of mounting features may be used in alternative embodiments. The mounting features  142 - 148  cooperate to secure the straddle mount connector  102  to the circuit board  104 . The mounting features  142 - 148  directly engage the circuit board  104  to hold the straddle mount connector  102  in position on the circuit board  104  for soldering the power contacts  128  and/or the signal contacts  130  to the contact pads  112 . The mounting features  142 - 148  are attached to the circuit board  104  without the need for additional mounting hardware, such as fasteners. The mounting features  142 - 148  may clamp to the circuit board  104  without the need for additional mounting hardware. The mounting features  142 - 148  hold the circuit board  104  between the left side upper and lower mounting features  142 ,  144  and between the right side upper and lower mounting features  146 ,  148 . The left side upper and lower mounting features  142 ,  144  are received in a common opening  118  of the circuit board  104  and the right side upper and lower mounting features  146 ,  148  are received in a common opening  118  of the circuit board  104 . 
     The left side upper mounting feature  142  extends from the mounting end  124  of the housing  120  proximate to the left side  136  of the housing  120 . The mounting feature  142  includes an arm  150  having a base  152 . The arm  150  extends to a distal end  154 . The arm  150  has a convex portion  156  that extends into the opening  118  of the circuit board  104 . The mounting feature  142  has a side  158  defining the longitudinally outermost portion of the straddle mount connector  102 . In the illustrated embodiment, the base  152  extends outward from the left side  136  of the housing  120  and the arm  150  extends rearward from the base  152  to the distal end  154 . The convex portion  156  is provided between the base  152  and the distal end  154 . The convex portion  156  extends towards the circuit board  104 . The convex portion  156  is the portion of the arm  150  that extends into the opening  118 . With the convex portion  156  held within the opening  118 , the straddle mount connector  102  is securely held to the circuit board  104 . The convex portion  156  is shaped to fit in the opening  118  in a snug manner to resist movement of the straddle mount connector  102  with respect to the circuit board  104 . 
     The left side lower mounting feature  144  extends from the mounting end  124  of the housing  120  proximate to the left side  136  of the housing  120 . The mounting feature  144  includes an arm  160  having a base  162 . The arm  160  extends to a distal end  164 . The arm  160  has a convex portion  166  that extends into the opening  118  of the circuit board  104 . The mounting feature  144  has a side  168  defining the longitudinally outermost portion of the straddle mount connector  102 . In the illustrated embodiment, the base  162  extends outward from the left side  136  of the housing  120  and the arm  160  extends rearward from the base  162  to the distal end  164 . The convex portion  166  is provided between the base  162  and the distal end  164 . The convex portion  166  extends towards the circuit board  104 . The convex portion  166  is the portion of the arm  160  that extends into the opening  118 . With the convex portion  166  held within the opening  118 , the straddle mount connector  102  is securely held to the circuit board  104 . The convex portion  166  is shaped to fit in the opening  118  in a snug manner to resist movement of the straddle mount connector  102  with respect to the circuit board  104 . 
     The right side upper mounting feature  146  extends from the mounting end  124  of the housing  120  proximate to the right side  138  of the housing  120 . The mounting feature  146  includes an arm  170  having a base  172 . The arm  170  extends to a distal end  174 . The arm  170  has a convex portion  176  that extends into the opening  118  of the circuit board  104 . The mounting feature  146  has a side  178  defining the longitudinally outermost portion of the straddle mount connector  102 . In the illustrated embodiment, the base  172  extends outward from the right side  138  of the housing  120  and the arm  170  extends rearward from the base  172  to the distal end  174 . The convex portion  176  is provided between the base  172  and the distal end  174 . The convex portion  176  extends towards the circuit board  104 . The convex portion  176  is the portion of the arm  170  that extends into the opening  118 . With the convex portion  176  held within the opening  118 , the straddle mount connector  102  is securely held to the circuit board  104 . The convex portion  176  is shaped to fit in the opening in a snug manner to resist movement of the straddle mount connector  102  with respect to the circuit board  104 . 
     The right side lower mounting feature  148  extends from the mounting end  124  of the housing  120  proximate to the right side  138  of the housing  120 . The mounting feature  148  includes an arm  180  having a base  182 . The arm  180  extends to a distal end  184 . The arm  180  has a convex portion  186  that extends into the opening  118  of the circuit board  104 . The mounting feature  148  has a side  188  defining the longitudinally outermost portion of the straddle mount connector  102 . In the illustrated embodiment, the base  182  extends outward from the right side  138  of the housing  120  and the arm  180  extends rearward from the base  182  to the distal end  184 . The convex portion  186  is provided between the base  182  and the distal end  184 . The convex portion  186  extends towards the circuit board  104 . The convex portion  186  is the portion of the arm  180  that extends into the opening  118 . With the convex portion  186  held within the opening  118 , the straddle mount connector  102  is securely held to the circuit board  104 . The convex portion  186  is shaped to fit in the opening  118  in a snug manner to resist movement of the straddle mount connector  102  with respect to the circuit board  104 . 
     The straddle mount connector  102  includes combs  190  extending from the mounting end  124  of the housing  120 . One comb  190  extends from the housing  120  proximate to the top  132 , defining an upper comb, while another comb  190  extends from the housing  120  proximate to the bottom  134 , defining a lower comb. The combs  190  are arranged adjacent to and interspersed between the signal contacts  130 . Each comb  190  includes a plurality of fingers  192  separated from one another by gaps  194 . The comb  190  is positioned with respect to the signal contacts  130  such that the fingers  192  are positioned between corresponding signal contacts  130  and the signal contacts  130  are positioned within corresponding gaps  194 . The fingers  192  electrically separate the signal contacts  130  from one another. The fingers  192  prevent bridging of solder paste on the contact pads  112  between adjacent contact pads  112 . In an alternative embodiment, the straddle mount connector  102  may not include any combs. Rather, the signal contacts  130  may be positioned adjacent one another without fingers therebetween. 
       FIG. 3  is a top view of the straddle mount connector  102  mounted to the circuit board  104 . The straddle mount connector  102  is mounted to the mating edge  110  of the circuit board  104 . The power contacts  128  engage corresponding contact pads  112 . The signal contacts  130  engage corresponding contact pads  112 . The power contacts  128  and signal contacts  130  may be soldered to the contact pads  112  after the straddle mount connector  102  is mounted to the circuit board  104 . The power contacts  128  and signal contacts  130  are arranged within the contact region  116  between the opposite openings  118  on opposite-sides of the contact region  116 . 
     The mounting features  142 - 148  ( 144  and  148  are shown in  FIG. 1 ) engage the corresponding openings  118  of the circuit board  104  to hold the straddle mount connector  102  onto the circuit board  104 . The openings  118  are longitudinally offset from the contact region  116  along the longitudinal axis  114 . In the illustrated embodiment, the openings  118  are circular in shape, however the openings  118  may have other shapes in alternative embodiments, such as rectangular shapes. The openings  118  have longitudinally outermost points  200 ,  202 . 
     A window  204  is defined between the longitudinally outermost points  200 ,  202  of the openings  118 . The window  204  has a width  206  that defines a longitudinal envelope that receives the straddle mount connector  102 . In an exemplary embodiment, the straddle mount connector  102  is coupled to the circuit board  104  such that no portion of the straddle mount connector  102  extends outside of the window  204 . The straddle mount connector  102  is entirely contained within the envelope defined by the window  204 . 
     The sides  158 ,  178  of the left side upper mounting feature  142  and the right side upper mounting feature  146 , respectively, define the longitudinally outermost portions of the straddle mount connector  102 . The straddle mount connector  102  has a width  208  defined between the sides  158 ,  178 . In an exemplary embodiment, the width  208  is less than the width  206 . The sides  158 ,  178  are held longitudinally inside of the longitudinally outermost points  200 ,  202  of the openings  118 . Having the width  208  less than the width  206  allows other electrical components to be mounted on the circuit board  104  closer to the contact region  116  than if the width  208  was wider than the width  206 . 
     Optionally, a second straddle mount connector (not shown) may be mounted to the circuit board  104  adjacent the straddle mount connector  102 . The second straddle mount connector may have mounting features that are received in the same opening  118  as the mounting feature  142  or the mounting feature  146 . For example, the mounting feature  142  may fill less than half of the opening  118  on the left side and mounting feature  146  may fill less than half of the opening  118  on the right side. Identical straddle mount connectors may be mounted adjacent one another such that the mounting feature  142  of the straddle mount connector  102  is received in the same opening  118  as a mounting feature of the second straddle mount connector. Other types of electrical components other than straddle mount connectors may be mounted to the circuit board  104  adjacent the opening  118 . Optionally, the other electrical components may be mounted immediately adjacent the longitudinally outermost points  200 ,  202  of the openings  118 . 
       FIG. 4  is a bottom view of a portion of the straddle mount connector  102  and the circuit board  104  showing the mounting feature  146  received in the opening  118 . The opening  118  is represented by a circular opening having a centerline  210  dividing the opening  118  into an outer portion  212  and an inner portion  214 . Other shaped openings are possible in alternative embodiments, such as rectangular openings. The inner portion  214  is positioned between the outer portion  212  and the contact region  116  (shown in  FIG. 3 ). The mounting feature  146  is received in the inner portion  214  such that the side  178  is positioned either at, or inside of, the centerline  210 . As such, the mounting feature  146  fills less than half the opening  118 . Another electrical component, such as a second straddle mount connector may be mounted to the circuit board  104  such that a mounting feature of such electrical component is also received within the opening  118  in the outer portion  212 . For example,  FIG. 4A  illustrates a second straddle mount connector  102 ′ mounted to the circuit board  104  such that a mounting feature  142  of the second straddle mount connector  102 ′ is also received in the opening  118 . In the illustrated embodiment, the portion of the mounting feature  146  received in the opening  118  is semi-circular in shape. Other shapes are possible in alternative embodiments. 
       FIG. 5  is a cross-sectional view of the straddle mount connector  102  mounted to the circuit board  104 . The left side  136  of the straddle mount connector  102  is shown in  FIG. 5 . The left side upper mounting feature  142  and the left side lower mounting feature  144  are received in the opening  118 . The upper and lower mounting features  142 ,  144  both engage the circuit board  104  to hold the straddle mount connector  102  on the circuit board  104 . When the straddle mount connector  102  is mounted to the circuit board  104 , the power contacts  128  and signal contacts  130  (shown in  FIG. 1 ) are coupled to corresponding contact pads  112  on both the first surface  106  and the second surface  108  of the circuit board  104 . 
     During mounting of the straddle mount connector  102  to the circuit board  104 , the upper and lower mounting features  142 ,  144  are spread apart and deflected outward by the mating edge  110  of the circuit board  104 . The arm  150  may be deflected outward by rotating the distal end  154  in a clockwise direction about the base  152 . The arm  160  may be deflected by rotating the distal end  164  in a counter-clockwise direction about the base  162 . The arms  150 ,  160  may be spread apart to allow the circuit board  104  to pass therebetween. Once the convex portions  156 ,  166  are aligned with the opening  118 , the convex portions  156 ,  166  drop into the opening  118  to hold the straddle mount connector  102  on the circuit board  104 . The straddle mount connector  102  is loaded onto the mating edge  110  until the upper and lower mounting features  142 ,  144  are aligned with, and received in, the opening  118 . 
     The convex portions  156 ,  166  are curved toward one another. The arm  150  includes an interior portion  220  that extends into the opening  118 . Similarly, the arm  160  includes an interior portion  222  that extends into the opening  118 . The interior portions  220 ,  222  are positioned interior of the first and second surfaces  106 ,  108 , respectively. The distal ends  154 ,  164  extend rearward from the convex portions  156 ,  166  and are positioned outside of the opening  118 . 
     When assembled, the upper and lower mounting features  142 ,  144  clamp the circuit board  104  therebetween. The upper mounting feature  142  provides a downward biasing force against the circuit board  104 . The lower mounting feature  144  provides an upward biasing force against the circuit board  104 . Optionally, as shown in  FIG. 5A , the upper and lower mounting features  142 ,  144  may engage one another within the opening  118 . The upper and lower mounting features  142 ,  144  may be secured to one another, such as using an adhesive on one or both of the upper and lower mounting features  142 ,  144 . Alternatively, the upper and lower mounting features  142 ,  144  may be secured to one another using other securing means, such as a fastener passing through the convex portions  156 ,  166 . 
     In an exemplary embodiment, the upper and lower mounting features  142 ,  144  engage a front  224  of the opening  118  and a rear  226  of the opening  118 . The interface between the mounting features  142 ,  144  and the front  224  prevents the straddle mount connector  102  from being moved forward with respect to the circuit board  104 . The interface between the mounting features  142 ,  144  and the rear  226  prevents the straddle mount connector  102  from moving rearward with respect to the circuit board  104 . The mounting, features  142 ,  144  thus hold the straddle mount connector  102  in position with respect to the circuit board  104  such that the power contacts  128  and signal contacts  130  may be soldered to the contact pads  112 . 
       FIG. 6  illustrates an alternative straddle mount connector  302  formed in accordance with an alternative embodiment. The straddle mount connector  302  is similar to the straddle mount connector  102  (shown in  FIG. 1 ), however, the straddle mount connector  302  includes mounting features  304  that differ from the mounting features  142 ,  144 ,  146 ,  148  (shown in  FIGS. 1 and 2 ). 
     The mounting features  304  are separate and discrete from a housing  320  of the straddle mount connector  302 . The mounting features  304  are securely coupled to the housing  320 . Optionally, the mounting features  304  may be manufactured from a different material than the housing  320 . For example, the housing  320  may be fabricated from a dielectric material, such as a plastic material. The mounting features  304  may be fabricated from a metal material. The mounting features  304  may be manufactured from a material having a high spring characteristic that allow the mounting features  304  to be spring biased against the circuit board  104  (shown in  FIGS. 1 and 2 ). The mounting features  304  provide a high clamping force therebetween to hold the straddle mount connector  302  in position with respect to the circuit board  104 . 
     The straddle mount connector  302  is assembled by coupling the mounting features  304  to the housing  320 . For example, the mounting features  304  may be loaded into openings  322  in the housing  320  and secured thereto by an interference fit between the mounting features  304  and housing  320 . The straddle mount connector  302  is then mounted to the circuit board  104  in a similar manner as the straddle mount connector  102 . The mounting features  304  are configured to be received in the openings  118  (shown in  FIGS. 1 and 2 ) of the circuit board  104  to secure the straddle mount connector  302  to the circuit board  104 . 
     It is to be understood that the above description is intended to be illustrative, and not restrictive. 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 adapt 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 exemplary 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 appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means-plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.