Patent Publication Number: US-2015072564-A1

Title: Interface assembly having electrically connected stab coupling and secondary coupling assemblies

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The disclosed and claimed concept relates to a panel board and, more specifically, to an interface assembly for a panel board. 
     2. Background Information 
     A panel board, or other type of load center, includes a number of conductive members disposed in a housing assembly defining an enclosure. The conductive members include “stabs” to which a panel board device, such as, but not limited to, a circuit breaker, is attached. That is, the conductive members, as shown, are planar members and the stab is a generally planar tab extending generally perpendicular thereto. A panel board device includes a conductive spring clip that engages the stab and thereby couples the panel board device to the conductive member. This is a disadvantage in that a coupling that relies upon friction is not always secure. 
     Further, the panel board device must include a coupling that is compatible with the size and shape of the stab. This is a disadvantage as not every device that could be conveniently disposed in the panel board housing assembly can be, or needs to be, directly coupled to a stab. 
     There is, therefore a need for an interface device that is coupled to the stabs of a panel board, but which provides one or more terminals to which panel board devices may be coupled. There is a further need for such a device to provide a secure electrical coupling. 
     SUMMARY OF THE INVENTION 
     These needs, and others, are met by at least one embodiment of this invention which provides an interface assembly. The interface assembly is structured to be mounted in a panel board and includes an interface assembly body and a number of conductor assemblies. The interface assembly body includes a front side and a back side, said body further defining a number of conductor passages. Each conductor passage extends from said interface assembly body front side to said body back side. The conductor assemblies each includes a stab coupling assembly and a secondary coupling assembly. Each stab coupling assembly and each said secondary coupling assembly are coupled and are in electrical communication. Each stab coupling assembly is disposed in a conductor passage. When the interface assembly body is mounted in a panel board, each stab coupling assembly is coupled to, and in electric communication with a stab. 
     Each secondary coupling assembly can be coupled to another panel board device. Further, each secondary coupling assembly includes a secure coupling, such as, but not limited to, a tapped passage. Thus, the other panel board device can be secured to the interface assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A full understanding of the invention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which: 
         FIG. 1  is a partial isometric view of a panel board. 
         FIG. 2  is a detail end view of a panel board. 
         FIG. 3  is a detail isometric view of a panel board. 
         FIG. 4  is an exploded view of an interface assembly and conductor assembly. 
         FIG. 5  is a bottom isometric view of an interface assembly. 
         FIG. 6  is an isometric view of an interface assembly with an exploded locking coupling assembly. 
         FIG. 7  is a detail isometric view of one embodiment of a lock pin. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Directional phrases used herein, such as, for example, clockwise, counterclockwise, left, right, top, bottom, upwards, downwards and derivatives thereof, relate to the orientation of the elements shown in the drawings and are not limiting upon the claims unless expressly recited therein. 
     As used herein, the singular form of “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. 
     As used herein, the statement that two or more parts or components are “coupled” shall mean that the parts are joined or operate together either directly or indirectly, i.e., through one or more intermediate parts or components, so long as a link occurs. As used herein, “directly coupled” means that two elements are directly in contact with each other. As used herein, “fixedly coupled” or “fixed” means that two components are coupled so as to move as one while maintaining a constant orientation relative to each other. Accordingly, when two elements are coupled, all portions of those elements are coupled. A description, however, of a specific portion of a first element being coupled to a second element, e.g., an axle first end being coupled to a first wheel, means that the specific portion of the first element is disposed closer to the second element than the other portions thereof. Further, an object resting on another object held in place only by gravity is not “coupled” to the lower object unless the upper object is otherwise coupled thereto. That is, for example, a book resting on a table is not coupled thereto, but a book glued to a table is coupled thereto. 
     As used herein, a “coupling assembly” includes two or more couplings or coupling components. The components of a coupling or coupling assembly are generally not part of the same element or other component. As such, the components of a “coupling assembly” may not be described at the same time in the following description. 
     As used herein, a “coupling” or “coupling component(s)” is one or more component(s) of a coupling assembly. That is, a coupling assembly includes at least two components that are structured to be coupled together. It is understood that the components of a coupling assembly are compatible with each other. For example, in a coupling assembly, if one coupling component is a snap socket, the other coupling component is a snap plug, or, if one coupling component is a bolt, then the other coupling component is a nut. 
     As used herein, the statement that two or more parts or components “engage” one another shall mean that the elements exert a force or bias against one another either directly or through one or more intermediate elements or components. 
     As used herein, “secure” and/or “lock” means that a coupling utilizes two components, one stationary and one movable and wherein the movable component rotates or slides between a first position, wherein the movable component does not engage the stationary component and a second position, wherein the movable component engages the stationary component. It is noted that a lock assembly, such as but not limited to a deadbolt on a door, meets this definition in that the deadbolt only performs the locking function when an attempt is made to open the door and the deadbolt engages the latch plate. It is further noted that a coupling such as a spring clip does not secure” and/or “lock” elements together as it flexes between a first and second position. 
     As used herein, an “easy release” locking coupling is a coupling wherein the movable component can be decoupled from the stationary component with a minimal motion such as, but not limited to, a rotational motion of about 180 degrees or less. Further, the identified range is the range intended for the movable component. That is, the fact that a bolt may be inserted into a nut by half a turn does not make a bolt and a nut an “easy release” locking coupling and as used herein, a bolt and a nut are specifically excluded from the definition of an “easy release” locking coupling. 
     As used herein, the word “unitary” means a component is created as a single piece or unit. That is, a component that includes pieces that are created separately and then coupled together as a unit is not a “unitary” component or body. 
     As used herein, the term “number” shall mean one or an integer greater than one (i.e., a plurality). 
     As used herein, “associated” means that the elements are part of the same assembly and/or operate together, or, act upon/with each other in some manner. For example, an automobile has four tires and four hub caps. While all the elements are coupled as part of the automobile, it is understood that each hubcap is “associated” with a specific tire. 
     As used herein, “correspond” indicates that two structural components are sized and shaped to be similar to each other and may be coupled with a minimum amount of friction. Thus, an opening which “corresponds” to a member is sized slightly larger than the member so that the member may pass through the opening with a minimum amount of friction. This definition is modified if the two components are said to fit “snugly” together or “snuggly correspond.” In that situation, the difference between the size of the components is even smaller whereby the amount of friction increases. If the element defining the opening and/or the component inserted into the opening are made from a deformable or compressible material, the opening may even be slightly smaller than the component being inserted into the opening. This definition is further modified if the two components are said to “substantially correspond.” “Substantially correspond” means that the size of the opening is very close to the size of the element inserted therein; that is, not so close as to cause substantial friction, as with a snug fit, but with more contact and friction than a “corresponding fit,” i.e., a “slightly larger” fit. Further, as used herein, “loosely correspond” means that a slot or opening is sized to be larger than an element disposed therein. This means that the increased size of the slot or opening is intentional and is more than a manufacturing tolerance. Further, with regard to a surface formed by two or more elements, a “corresponding” shape means that surface features, e.g. 
     curvature, are similar. 
     As used herein, “structured to [verb]” means that the identified element or assembly has a structure that is shaped, sized, disposed, coupled and/or configured to perform the identified verb. For example, a member that is “structured to move” is movably coupled to another element and includes elements that cause the member to move or the member is otherwise configured to move in response to other elements or assemblies. 
     As used herein, “at” means on or near. 
     As shown in  FIGS. 1 and 2 , and in an exemplary embodiment, a panel board  10  is an assembly including a housing assembly  12  (shown in part) and a number of conductive members  14 . In an exemplary embodiment, the housing assembly  12  is made of metal. As is known, the housing assembly  12  includes a number of sidewalls, including a door (not shown), that define an enclosed space. As shown, the housing assembly  12  includes a back plate  16 . The back plate  16  is a generally planar body  18  that further includes generally planar peripheral flanges  20 ,  22  that extend generally perpendicular to the plane of the back plate body  18 . The peripheral flanges  20 ,  22  in turn include outwardly extending flanges  24 ,  26  that extend generally perpendicular to the plane of the associated peripheral flanges  20 ,  22 . Each outwardly extending flange  24 ,  26  includes a number of mounting constructs  30 . Each mounting construct  30  includes a spacer member  32  and a mounting tab  34 . Each spacer member  32  extends generally perpendicular to the plane of the associated outwardly extending flange  24 ,  26  and generally parallel to the plane of the associated peripheral flanges  20 ,  22 . Each mounting tab  34  is a generally planar member  36  extending over, and generally perpendicular to the plane of, the associated peripheral flanges  20 ,  22 , and, generally perpendicular to the plane of the spacer member  32  from which it depends. That is, each mounting tab planar member  36  includes a proximal end  38  and a distal end  39 . Each tab proximal end  38  is flexibly coupled to the associated spacer member  32 , or stated broadly, flexibly coupled to the panel board housing assembly back plate  16 . In this configuration, each mounting tab  34  moves between a non-flexed, first position, wherein the mounting tab  34  extends generally parallel to the plane of the panel board housing assembly back plate  16 , and a flexed, second position wherein the mounting tab  34  is generally angled relative to the plane of the panel board housing assembly back plate  16 . In the second mounting tab  34  position, each mounting tab  34  creates a bias. 
     In an exemplary embodiment, the number of conductive members  14  include a first phase conductor  40  and a second phase conductor  42 . As shown in  FIG. 3 , the first phase conductor  40  and second phase conductor  42  each include a generally planar portion  44 ,  46  that are disposed in adjacent, generally parallel planes. A non-conductive barrier (not shown) is disposed between the first phase conductor  40  and second phase conductor  42 . The first phase conductor  40  and second phase conductor  42  each include a number of stabs  48 ,  50 . Each stab  48 ,  50  includes a planar body  52 ,  54 , that extends generally perpendicular to the plane of the first phase conductor  40  and second phase conductor  42 . In an exemplary embodiment, the first phase conductor planar portion  44  has a serpentine shape, thereby allowing the second phase conductor stabs  50  to extend between gaps in the first phase conductor planar portion  44 . Thus, the stabs  48 ,  50  are generally aligned and spaced from each other. 
     A panel board device  58  includes, but is not limited to, constructs structured to be coupled to the stabs  48 ,  50  and/or disposed within the housing assembly  12  such as, but not limited to, a Molded Case SPD (Molded Case Surge Protection Device). As shown in  FIGS. 1-3 , in an exemplary embodiment, the panel board device  58  is represented by an interface assembly  60 . That is, the interface assembly  60  is a panel board device  58 . As such, it is understood that any element described in association with an interface assembly  60  is also applicable to a panel board device  58 . Thus, it is understood, for example, that interface assembly body  62 , described below, is also a “panel board device body.” It is further noted, however, that the interface assembly  60  is, as described below, structured to support other components, such as but not limited to, other panel board devices  58  and printed circuit board devices (not shown), whereas a panel board device  58  may have other functions and may not include all of the elements of the interface assembly  60 . 
     As shown in  FIGS. 3 and 4 , in an exemplary embodiment, the interface assembly  60  includes a body  62 , number of conductor assemblies  150 , and a number of locking member assemblies  190  ( FIG. 1 ). In an exemplary embodiment, the interface assembly body  62  is made from a non-conductive material. In an exemplary embodiment, the interface assembly body  62  includes an elongated, generally planar member  64 . The interface assembly body  62  includes a front side  66  and a back side  68  ( FIG. 5 ). The interface assembly body  62  defines a number of passages including a number of conductor passages  70  and a number of mounting passages  110 . 
     In an exemplary embodiment, the interface assembly body  62  is generally rectangular and includes a flange  72  extending about the interface assembly body planar member  64  thereby defining a support compartment  74 . A number of components, e.g. printed circuit board devices, can be disposed in the support compartment  74 . The interface assembly body  62  further includes a number of collars  76 . Each collar  76  extends about a conductor passage  70 . The collars  76  are disposed on either, or both, the interface assembly body planar member front side  66  and/or back side  68 . Further, each conductor passage  70  includes a first portion  80  and a second portion  82  which, in an exemplary embodiment, are a first lateral portion and a second lateral portion. In an exemplary embodiment, each collar  76  disposed on the interface assembly body planar member front side  66  includes a top member  84  substantially extending over the conductor passage first portion  80 . That is, as shown in  FIG. 4 , a collar  76  and a collar top member  84 , in an exemplary embodiment, includes a slot  86  extending across the associated conductor passage  70 . 
     In an exemplary embodiment, the number of conductor passages  70  includes a first conductor passage  90  and a second conductor passage  92 . Accordingly, the number of collars  76  includes a first collar  94  and a second collar  96 . The first collar  94  is disposed about the first conductor passage  90  and is located on the interface assembly body front side  66 . The second collar  96  is disposed about the second conductor passage  92  and is located on the interface assembly body front side  66 . In an exemplary embodiment, the first and second conductor passages  90 ,  92 , and therefore the first and second collars  94 ,  96 , are disposed medially on the interface assembly body  62 . In this configuration, the first and second collars  94 ,  96  separate the support compartment  74  into a first lateral support compartment  98  and a second lateral support compartment  100 . 
     In an exemplary embodiment, the interface assembly body  62  is structured to be secured to a panel board housing assembly  12  by the locking member assembly  190 . The locking member assemblies  190  are each disposed in a mounting passage  110 . Each mounting passage  110 , in an exemplary embodiment, is generally circular and extends generally perpendicular to the plane of the interface assembly body planar member  64 . Each mounting passage  110  includes an upper first end  112 , disposed at the interface assembly body front side  66 , and a lower, second end  114 , disposed at the interface assembly body back side  68 . 
     As set forth below, the locking member assembly  190  includes features that interact with the interface assembly body  62  and, more specifically, with the mounting passages  110 . That is, as discussed below and shown in  FIGS. 6 and 7  , the locking member assembly  190 , and more specifically, a lock pin assembly  210 , includes elongated bodies  212  each disposed in a mounting passage  110 . Further, the lock pin assembly bodies  212  move axially within a mounting passage  110 . Further, the lock pin assembly bodies  212  include a number of radial extensions  230 ,  240 . To accommodate these motions and the lock pin assembly body radial extensions  230 ,  240 , each mounting passage  110  includes a radial cavity  120  ( FIG. 4 ). Each radial cavity  120  is positioned so as to engage a lock pin assembly body radial extension  230 ,  240  when the lock pin assembly body  212  is in a second radial position and a first axial position, as discussed below. That is, each radial cavity  120  includes an upper surface  122 , discussed below, that extends generally perpendicular to the mounting passage  110 . The radial cavity upper surface  122  is, in one embodiment (not shown), a unitary part of the interface assembly body  62 . In an exemplary embodiment, the radial cavity upper surface  122  is part of a first biasing device mounting  258 , discussed below, that is not unitary with the interface assembly body  62 . 
     In an exemplary embodiment, each mounting passage  110  further includes a first locking pocket  130 , and a second locking pocket  132 , shown in  FIG. 5 . Both the first and second locking pockets  130 ,  132  are disposed at the mounting passage second end  114  and are radially spaced from each other. The first and second locking pockets  130 ,  132  are open at the mounting passage second end  114 . That is, the first and second locking pockets  130 ,  132  can be accessed axially from the mounting passage second end  114 . 
     In an exemplary embodiment, there are two mounting passages  110 , a first mounting passage  140  and a second mounting passage  142 . In an exemplary embodiment, each of the first and second mounting passages  140 ,  142  is disposed at the longitudinal axis of the interface assembly body planar member  64 . Further, each of the first and second mounting passages  140 ,  142  is disposed at the lateral side of the interface assembly body planar member  64 . In another exemplary embodiment, not shown, there are four mounting passages  110 , each disposed at a corner of the interface assembly body planar member  64 . 
     As shown in  FIG. 5 , each conductor assembly  150  includes a stab coupling assembly  152  and a secondary coupling assembly  154 . The stab coupling assembly  152  and the secondary coupling assembly  154  are each made from a conductive material. 
     Each stab coupling assembly  152  is structured to be coupled to, and be in electrical communication with, one of the stabs  48 ,  50 . Each secondary coupling assembly  154  is structured to be coupled to, and be in electrical communication with another panel board device (not shown). Further, the stab coupling assembly  152  and the secondary coupling assembly  154  in a conductor assembly  150  are coupled, directly coupled or fixed to each other and are in electrical communication. 
     Each stab coupling assembly  152  is disposed in a conductor passage  70 . In an exemplary embodiment, each stab coupling assembly  152  is a spring clip  160 . As used herein, a “spring clip” is a construct including a number of movable members wherein a movable member is biased against another movable member or a stationary member; in an exemplary embodiment, the movable members are flexibly coupled to each other or a stationary member. Thus, the members move between a number of positions including a closed, first position, wherein the members contact each other or are disposed relatively close to each other, and an open, second position; in the second position, wherein the members are spaced from each other a greater distance than when in the first position and wherein the movable members are biased against any element disposed between the members. As shown in  FIG. 4  an exemplary spring clip  160  includes a body  162  shaped as a generally planar triangular loop, i.e. a hollow triangle, wherein the sides of the spring clip body  162  are not joined at one corner  164 . 
     The secondary coupling assembly  154 , in an exemplary embodiment, includes a generally planar, elongated body  170  with a generally perpendicular extension  172 . The secondary coupling assembly perpendicular extension  172  is a terminal  174 . As used herein, a “terminal” is a portion of a conductive member that is structured to be coupled to another conductive member. That is, a portion of a conductive member that can be coupled, i.e. is merely capable of being coupled, to another conductive member, is not a “terminal.” The secondary coupling assembly perpendicular extension  172  includes a tapped passage  176 . The secondary coupling assembly body  170 , in an exemplary embodiment, is coupled to, directly coupled to, or fixed to a spring clip body  162  and extends generally perpendicular to the plane of the spring clip body  162 . 
     As shown in  FIG. 5 , each conductor assembly  150  is disposed in a conductor passage  70  with the stab coupling assembly  152 , i.e. the spring clip body  162  disposed in conductor passage first portion  80 . Further, the secondary coupling assembly  154 , i.e. the planar, elongated body  170 , is disposed on the interface assembly body front side  66 . In this configuration, the stab coupling assembly  152  is structured to engage, i.e. be coupled to and in electrical communication with, a stab  48 ,  50  with the stab  48 ,  50  entering the conductor passage  70  from the interface assembly body back side  68 . Further, each secondary coupling assembly  154 , and more specifically, each secondary coupling assembly perpendicular extension  172  is disposed in the support compartment  74 . Further, in this configuration, the portion of the secondary coupling assembly  154  disposed in the conductor passage second portion  82  can also be used as a terminal  174 A. That is, a coupling , such as but not limited to a spring clip  160 , can be coupled to the terminal  174 A. 
     It is noted that, during assembly, the conductor assembly  150  can be positioned on the interface assembly body planar member front side  66  with the stab coupling assembly  152 , i.e. the spring clip body  162 , aligned with the conductor passage second portion  82 . The stab coupling assembly  152 , i.e. the spring clip body  162 , is moved into the conductor passage second portion  82  with the secondary coupling assembly  154 , i.e. 
     the planar, elongated body  170 , passing through, or disposed in, the slot  86 . The conductor assembly  150  can then be moved until the stab coupling assembly  152 , i.e. the spring clip body  162 , is disposed in conductor passage first portion  80 . 
     Further, as noted above, in an exemplary embodiment, there is a first conductor passage  90  and a second conductor passage  92 . Accordingly, in an exemplary embodiment, there is a first conductor assembly  180  and a second conductor assembly  182 . The first conductor assembly  180  is disposed in the first conductor passage  90  and the second conductor assembly  182  is disposed in the second conductor passage  92 . Further, as noted above, in this configuration, the support compartment  74  is divided into a first lateral support compartment  98  and a second lateral support compartment  100 . In an exemplary embodiment, the first conductor assembly  180  is oriented so that the first conductor assembly secondary coupling assembly perpendicular extension  172  (hereinafter, “first conductor assembly perpendicular extension”) is disposed in the first lateral support compartment  98 . Further, the second conductor assembly  182  is oriented so that the second conductor assembly secondary coupling assembly perpendicular extension  172  (hereinafter, “second conductor assembly perpendicular extension”) is disposed in the second lateral support compartment  100 . 
     Further, in an exemplary embodiment, the spacing of the first conductor passage  90  and the second conductor passage  92  correspond to the spacing of the tabs  48 ,  50 . In this configuration, the first conductor assembly  180  is disposed in the first conductor passage  90  and is structured to engage the stab  48  from the first phase conductor  40 . That is, the stab  48  is disposed in the stab coupling assembly  152 , i.e. the spring clip body  162 , and is thereby coupled to and in electrical communication therewith. Further, the second conductor assembly  182  is disposed in the second conductor passage  92  and is structured to engage the stab  50  from the second phase conductor  42 . That is, the stab  50  is disposed in the stab coupling assembly  152 , i.e. the spring clip body  162 , and is thereby coupled to and in electrical communication therewith. 
     The interface assembly  60 , or another embodiment of a panel board device  58 , is coupled to, and in an exemplary embodiment secured to, the panel board housing assembly  12 , and more specifically the back plate  16 , by a number of locking member assemblies  190 , as shown in  FIG. 1 . Each locking member assembly  190  is an element of a locking coupling assembly  200 . Each locking coupling assembly  200  includes the mounting tabs  34  and mounting passages  110  noted above, as well as the locking member assembly  190 . In an exemplary embodiment, the number of locking member assemblies  190  include a number of lock pin assemblies  210 . 
     As shown in  FIG. 6 , a lock pin assembly  210  includes a body  212  (hereinafter “lock pin body”) and a biasing assembly  214 . As shown in  FIG. 7 , the lock pin body  212  includes a first end  220  and a second end  222 . Between the lock pin body first end and second end  220 ,  222  there is a first medial portion  224  and a second medial portion  226 . That is, as described below, the lock pin body  212  moves between an upper, first axial position and a lower, second axial position. When the lock pin body  212  is in the upper, first axial position, the portion of the lock pin body  212  above the panel board device body  62  is the first medial portion  224 . Further, when the lock pin body  212  is in the upper, first axial position, the portion of the lock pin body  212  within the mounting passage  110  and below the panel board device body  62  is the second medial portion  226 . A tool coupling  228 , such as but not limited to a slot for a screwdriver, is disposed at the lock pin body first end  220 . A first radial extension  230  is disposed at the lock pin body second end  222 . 
     In an exemplary embodiment, the lock pin assembly body  212  is generally cylindrical and the diameter corresponds to a mounting passage  110 . Thus, the lock pin assembly body  212  can be, and is, rotatably disposed in a mounting passage  110 . That is, the lock pin assembly body  212  is rotatably coupled to the panel board device body  62 . As noted above, each of the first and second mounting passages  140 ,  142  is disposed at the lateral side of the interface assembly body planar member  64 . In this configuration, the first radial extension  230  is disposed adjacent to the mounting tabs  34 . In this configuration, the lock pin body  212  is structured to be moved between an unlocked, first radial position, wherein the first radial extension  230  does not engage a panel board back plate mounting tab  34 , and a locked, second radial position, wherein the first radial extension  230  engages a panel board back plate mounting tab  34 . Further, the amount that the lock pin body  212  needs to be rotated is between about 70 degrees and 180 degrees, or in an exemplary embodiment about 90 degrees. Thus, the lock pin body  212  is an easy release locking coupling  186 . 
     The first radial extension  230  is disposed at the interface assembly body back side  68 , and thereby prevents the lock pin body  212  from moving upwardly in the associated mounting passage  110 . In an exemplary embodiment, a second radial extension  240  also engages the interface assembly body  62 . That is, the second radial extension  240  is disposed on the lock pin body second medial portion  226  and is structured to engage the radial cavity  120  in the associated mounting passage  110  when the lock pin body  212  is in the second radial position. 
     In an exemplary embodiment, shown in ghost in  FIG. 7 , the biasing assembly  214  is a cam that engages a mounting tab  34 . That is, in this embodiment, the panel board device body back side  68  is structured to, and does, contact the back plate outwardly extending flanges  24 ,  26 , as shown in  FIG. 2 . Thus, the panel board device body  62  cannot move toward the back plate outwardly extending flanges  24 ,  26 . Further, in this embodiment, the lock pin body  212  does not move axially in the associated mounting passage  110 . That is, for example, the radial cavity  120  has an axial dimension generally corresponding to the axial dimension of the second radial extension  240 . In this configuration, the lock pin body  212  does not move axially in the associated mounting passage  110 . Further, the first radial extension  230  includes an upper surface  250 . The first radial extension upper surface  250  is angled relative to the plane of rotation of the first radial extension  230 . That is, the first radial extension  230  has a narrow end  252  and a wide end  254 . In this configuration, the first radial extension upper surface  250  is a cam surface  256 . The first radial extension  230  is disposed adjacent a mounting tab  34  so that, when the lock pin body  212  is in the unlocked, first radial position, the first radial extension narrow end  252  is adjacent the mounting tab  34 . As the lock pin body  212  moves toward and into the second radial position, the cam surface  256  engages the mounting tab  34  causing the mounting tab  34  to flex. That is, flexing of the mounting tab  34  creates a bias acting on the lock pin body  212 . 
     In another exemplary embodiment, shown in  FIG. 6 , the biasing assembly  214  includes a first biasing device mounting  258 , a second biasing device mounting  260  and a biasing device  262 . In an exemplary embodiment, the first biasing device mounting  258  is a washer  259  disposed about each mounting passage  110 . The washer  259  provides a planar surface that is engaged by the biasing device  262  as well as providing a cover for the radial cavity  120  discussed above. Thus, the first biasing device mounting  258  is also, as used herein, a part of the panel board device body  62 . In an exemplary embodiment, the second biasing device mounting  260  is a projection assembly  264 . The projection assembly  264  includes a passage  266  through the lock pin body first medial portion  224  and a pin  268  extending therethrough. The projection assembly pin  268  is longer than the diameter of the lock pin body  212 . Thus, when the projection assembly pin  268  is disposed in the projection assembly passage  266 , the projection assembly pin  268  extends therefrom thereby creating a projection. 
     In an exemplary embodiment, the biasing device  262  is a compression spring  270 . The biasing device  262  includes a first end  272  and a second end  274 . The compression spring  270  extends between the first biasing device mounting  258  and the second biasing device mounting  260 . In this configuration, the biasing device  262 , and therefore the biasing assembly  214 , biases the lock pin body  212  to the upper, first axial position. In an exemplary embodiment, the biasing device first end  272  is coupled to the first biasing device mounting  258 , and, the biasing device second end  274  is coupled to the second biasing device mounting  260 . 
     In this exemplary embodiment, the lock pin body  212  further includes a locking lug  280 , shown in  FIG. 7 . The locking lug  280 , in an exemplary embodiment, is disposed axially inwardly from the first radial extension  230 . That is, the locking lug  280  extends axially from the first radial extension upper surface  250 . The locking lug  280  corresponds to the first and second locking pockets  130 ,  132 . In this configuration, when the lock pin body  212  is in the first radial position and the first axial position, the locking lug  280  is disposed in the first locking pocket  130 . Further, when the lock pin body  212  is in the second radial position and the first axial position, the locking lug  280  is disposed in the second locking pocket  132 . Further, when the lock pin body  212  is in the second axial position, the locking lug  280  is not disposed in either the first or second locking pocket  130 ,  132 . Thus, the lock pin body  212  cannot be substantially rotated when the lock pin body  212  is in the first axial position. That is, interference, i.e. contact, between the locking lug  280  and the surfaces defining the first and second locking pocket  130 ,  132  prevents rotation of the lock pin body  212 . 
     As noted above, in an exemplary embodiment there are two mounting passages  110 , a first mounting passage  140  and a second mounting passage  142 . In an exemplary embodiment, each of the first and second mounting passages  140 ,  142  is disposed at the longitudinal axis of the interface assembly body planar member  64 . In this embodiment, the number of lock pin assemblies  210  includes a first lock pin assembly  290  and a second lock pin assembly  292 . The first lock pin assembly  290  is rotatably disposed in the first mounting passage  140 , and, the second lock pin assembly  292  is rotatably disposed in the second mounting passage  142 . 
     A lock pin assembly  210  of this configuration is utilized as follows. If a panel board device  58 , e.g. interface assembly  60 , is not attached to a panel board  10 , and if the lock pin body  212  is in the first radial position and first axial position, a user positions the panel board device  58  between the opposing mounting tabs  34  on the panel board back plate  16  with the first and second mounting passages  140 ,  142 , and therefor each locking member assembly  190 , aligned with a mounting tab  34 . The user then applies bias to a lock pin body first end  220 , thereby overcoming the bias of the biasing assembly  214  and moving the lock pin body  212  to the second axial position. The user then rotates the lock pin body  212  to the second radial position and releases the pressure on the lock pin body first end  220 . The biasing assembly  214  then moves the lock pin body  212  to the second axial position. When the biasing assembly  214  moves the lock pin body  212  to the second axial position, bias is applied between the first radial extension  230  and a panel board back plate mounting tab  34 . Thus, the lock pin body  212  is in the second radial position. A lock pin assembly  210  of a configuration utilizing a cam surface  256  operates in a similar manner except there is no need to move the lock pin body  212  axially and the counter bias of the mounting tab  34  creates the engagement between the mounting tab  34  and the first radial extension  230 . 
     While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of invention which is to be given the full breadth of the claims appended and any and all equivalents thereof.