Abstract:
The junction box according to the invention includes a housing defined by a lower case and an upper case. A busbar substrate disposed within the housing includes a plurality of busbar substrates. The pier assembly is disposed on at least one of the lower case and one of the plurality of busbar substrates. The pier assembly either accommodates another of the plurality of busbar substrates or supports another of the plurality of busbar substrates. In one embodiment, the pier assembly is disposed on the lower case. In another embodiment, the pier assembly is disposed on one of the busbar substrates. In yet another embodiment, the pier assembly is disposed on the upper case. A method for assembling the junction box according to the invention includes providing a pier assembly for positioning a busbar substrate assembly and disposing a busbar substrate of the busbar substrate assembly in the lower case. The busbar substrate either receives the pier assembly therethrough or is supported on the pier assembly.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a junction box and a method of assembly thereof and, more particularly, a junction box intended for use in automobiles. 
     DISCUSSION OF THE INVENTION 
     Junction boxes are typically used in automobiles to connect electrical components. Often, they include a busbar substrate assembly housed within a casing, which typically includes an upper case and a lower case sealed by a gasket. The casing may have two or more connectors, which are used to form the electrical connection between electrical components. The busbar substrate assembly may include multiple busbar substrates, each including an insulating substrate and a busbar to provide the circuitry required to make an electrical connection between components. 
     Depending on the application, each busbar substrate provided within a junction box may not be utilized. That is, as junction boxes are made uniform across a vehicle platform or multiple platforms in order to save manufacturing costs, the junction box may include several busbar substrates but not utilize each busbar substrate for a given application depending upon the required circuitry. Eliminating a busbar substrate that is not required for a particular application to save manufacturing costs is not practically feasible because the spacing within the junction box cannot be maintained when eliminating a busbar substrate layer. If spacing is not maintained, excessive noise or damage may result from loosely fit busbar substrates. 
     In order to eliminate the noise and/or component damage that might result from loosely fit busbar substrates, and allowing an unnecessary busbar substrate to be removed to save manufacturing costs for a particular application, the junction box and method for assembly described in detail herein is provided. 
     Generally, the junction box according to the invention includes a housing for a busbar substrate assembly including a plurality of busbar substrates. The lower case includes spacing and positioning piers for alternatively positioning one of the plurality of busbar substrates or maintaining the spacing of another busbar substrate. More specifically, the junction box includes a housing defined by a lower case and an upper case, the busbar substrate assembly including a plurality of busbar substrates, each including an insulating substrate and a busbar, a pier assembly including one or more piers for positioning one of the busbar substrates or maintaining the spacing of the remaining busbar substrates, wherein the pier assembly is formed on the housing. In one version of the invention, the pier assembly is formed on the lower case. In a variation of the invention, the pier assembly includes a single pier. In another variation, the pier assembly includes multiple piers. 
     A method for assembling a junction box includes providing a housing having an upper case and a lower case, providing a pier assembly on the housing, providing a busbar substrate assembly including one or more busbar substrates, disposing a busbar substrate in the lower case, and maintaining a spacing within the housing by positioning the busbar substrate such that the pier assembly is received therethrough or positioning the busbar substrate on the pier assembly. 
     Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
     FIG. 1 illustrates an exploded perspective view of the junction box according to the invention; 
     FIG. 2 is a cross-section of an assembled junction box according to a configuration of the invention; 
     FIG. 3 is a cross-section of an assembled junction box according to another configuration of the invention; 
     FIG. 4 illustrates a perspective view of an alternative pier assembly configuration according to the invention; 
     FIG. 5 illustrates a perspective view of yet another pier assembly configuration according to the invention; 
     FIG. 6 illustrates an exploded perspective view of the junction box according to a variation of the invention; 
     FIG. 7 is a cross-section of an assembled junction box according to a configuration of the variation of the invention shown in FIG. 6; 
     FIG. 8 is a cross-section of an assembled junction box according to another configuration of the variation of the invention shown in FIG. 6; and 
     FIG. 9 is a cross-section of an assembled junction box according to yet another configuration of the variation of the invention shown in FIG.  6 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     Referring to FIGS. 1-5, a junction box  2  includes a busbar substrate assembly  10 , a housing  20 , and a pier assembly  30 . The junction box  2  may be mounted to a mounting surface  6 . The busbar substrate assembly  10  includes one or more busbar substrates  12 , each including an insulating substrate  14  and a busbar  16 . The housing  20  includes a lower case  22  and an upper case  24  sealed when assembled by a gasket (not shown) at the junction of the lower and upper cases  22 ,  24  to prevent water and/or debris from entering the junction box  2 . The pier assembly  30  includes one or more piers  32 . As shown, the housing  20  includes a male connector cavity  28  on an upper surface of the upper case  24  and contains male tab openings to receive tabs of busbar  16  inserted therethrough. 
     As shown, the busbar substrate assembly  10  includes busbar substrates  12   a ,  12   b ,  12   c . More or fewer busbar substrates  12  may be employed, depending on the particular application. Each busbar substrate  12   a ,  12   b ,  12   c  includes a corresponding insulating substrate  14   a ,  14   b ,  14   c  and a busbar  16   a ,  16   b ,  16   c . Further, at least one of the busbar substrates  12  includes one or more positioning apertures  18 . As shown, busbar substrate  12   c  includes positioning apertures  18   a ,  18   b ,  18   c ,  18   d . Further, each insulating substrate  14  includes insulating ribs  15  formed therein at positions corresponding to the busbar  16  so as to insulate the busbar  16  and maintain the position of the busbar  16  on the insulating substrate  14 . As shown in FIG. 1, insulating substrate  14   c  includes ribs  15   c.    
     The pier assembly  30  includes one or more piers  32  to space and/or position the busbar substrate assembly  10  in the housing  20 . Piers  32   a ,  32   b ,  32   c ,  32   d  are exemplary in shape and are complimentary to positioning apertures  18   a ,  18   b ,  18   c ,  18   d  in busbar substrate  12   c . The piers  32  can be of various shapes and configurations, with the shapes and configurations shown in FIG. 1 being merely a non-limiting example. For example, with reference to FIGS. 4 and 5, other pier assembly  30  configurations are shown, including a single pier  32 ′ and a pair of piers  32 ″. Again, the various pier shapes and configurations are exemplary and not limiting. 
     Each pier  32  is shaped to mate with a busbar substrate  12 , such as busbar substrate  12   c , wherein the positioning apertures  18  receive the piers  32  to position the busbar substrate  12   c  on the lower case  22 . The height of the piers  32  is similar to the height of the busbar substrate  12   c , whereby a top surface  34  of each pier  32  is generally planar with a top surface  13  of the busbar substrate  12   c . By removing the busbar substrate  12   c  in the manufacture of the junction box  2  for a particular vehicle application, the top surface  34  of each pier  32  supports the remaining busbar substrate assembly  10  at its proper position within the housing  20  through engagement with a bottom surface  11  of the busbar substrate  12   b . Thus, should the circuitry provided on busbar substrate  12   c  not be required, the busbar substrate  12   c  can be eliminated when manufacturing the junction box  2  without altering the positioning of the remaining busbar substrates  12   a ,  12   b  of the busbar substrate assembly  10 . In this manner, noise and/or damage from a loosely fit busbar substrate  12  is eliminated and the added expense of including an otherwise unnecessary busbar substrate  12   c  to maintain spacing is avoided. 
     To manufacture the junction box  2 , the lower case  22  is grasped by a chuck (not shown in the drawings) of an automated device and positioned relative to a positioning tool. If appropriate for a particular application, the busbar substrate  12   c  is grasped using the chuck of the automated device and positioning apertures  18   a ,  18   b ,  18   c ,  18   d  of busbar substrate  12   c  are aligned with piers  32   a ,  32   b ,  32   c ,  32   d , respectively, and positioned on lower case  22 . Because the piers  32   a ,  32   b ,  32   c  are inserted through positioning apertures  18   a ,  18   b ,  18   c ,  18   d , the busbar substrate  12   c  is reliably assembled and properly located on lower case  22 , as best shown in FIG.  2 . 
     If the busbar substrate  12   c  is not required for a particular application, the busbar substrate  12   b  is grasped using the chuck of the automated device and aligned with and mounted in lower case  22  on the pier assembly  30  such that the bottom surface  11  of busbar substrate  12   b  engages the top surfaces  34  of the piers  32   a ,  32   b ,  32   c . Because the pier assembly  30  supports the busbar substrate  12   b , busbar substrate  12   b  is reliably assembled and properly positioned in the lower case  22 , even in the absence of busbar substrate  12   c , as best shown in FIG.  5 . 
     Depending on the application, it may be appropriate to include the busbar substrate  12   a , which is grasped using the chuck of the automated device and positioned on busbar substrate  12   b . Certain applications, however, will not require that the junction box  2  include more than a single busbar substrate  12 , which in this example would be busbar substrate  12   b . To enclose the housing  20 , the upper case  24  is grasped with the chuck of the automated device and positioned on the lower case  22  to enclose the busbar substrate assembly  10  within the housing  20 . A gasket (not shown) may be included prior to seating the upper case  24  on the lower case  22  by grasping the gasket with the chuck of the automated device and positioning the gasket about the perimeter of the opening for the lower case  22 , whereby the housing is sealed. 
     As described, regardless of whether a particular busbar substrate  12 , i.e., busbar substrate  12   c  in the above description, is necessary for a particular vehicle application, the busbar substrate assembly  10  is nonetheless properly positioned within the housing  20  because the pier assembly  30  alternatively accommodates the busbar substrate  12   c  or positions the busbar substrate  12   b . Further, additional busbar substrates may be employed in layers on busbar substrate  12   b , such as busbar substrate  12   a  as described above. Although the above description has been described with reference to two or three busbar substrates  12 , it will be appreciated by those skilled in the art that fewer than two and more than three busbar substrates can be included in the junction box  2  in accordance with the present invention. 
     Referring to FIGS. 6-9, a variation of the invention is shown as a junction box  102  including a busbar substrate assembly  110 , a housing  120 , and a pier assembly  130 . The junction box  102  may be mounted to a mounting surface  106 . A busbar substrate assembly  112  includes one or more busbar substrate  112 , each including an insulating substrate  114  and a busbar  116 . The housing  120  includes a lower case  122  and an upper case  124  sealed when assembled by a gasket (not shown) at the junction of the upper and lower cases  122 ,  124  to prevent water and/or debris from entering the junction box  102 . The pier assembly  130  includes one or more piers  132 . As shown, the housing  120  includes a male connector cavity  128  on an upper surface of the upper case  124  and contains male tab openings to receive tabs of busbar  116  inserted therethrough. 
     As shown, the busbar substrate assembly  110  includes busbar substrates  112   a ,  112   b ,  112   c . More or fewer busbar substrates  112  may be employed depending on the particular application. Each busbar substrate  112   a ,  112   b ,  112   c  includes a corresponding insulating substrate  114   a ,  114   b ,  114   c  and a busbar  116   a ,  116   b ,  116   c . Further, each of the busbar substrates  112   a  and  112   c  includes one or more positioning apertures  118 . As shown, busbar substrate  112   c  includes positioning apertures  118   a ,  118   b ,  118   c ,  118   d  ; busbar substrate  112   a  includes positioning apertures  118   g ,  118   h ,  118   i ,  118   j  ; and busbar substrate  112   b  includes positioning apertures  118   e ,  118   f . Further, each insulating substrate  114  includes insulating ribs  115  formed therein at positions corresponding to the busbar  116  so as to insulate the busbar  116  to maintain the position of the busbar  116  on the insulating substrate  114 . As shown in FIG. 1, insulating substrate  114   c  includes ribs  115   c.    
     The pier assembly  130  includes one or more piers  132  to space and/or position the busbar substrate  110  and the housing  120 . Piers  132   a ,  132   b ,  132   c ,  132   d  extend upwardly from the bottom surface of the lower case  122 , and are exemplary in shape and complimentary to positioning apertures  118   a ,  118   b ,  118   c ,  118   d  in busbar substrate  112   c . Further, piers  132   e ,  132   f  extend upwardly from a top surface  113  of busbar substrate  112   c , and are exemplary in shape and complimentary to positioning apertures  118   e ,  118   f  in busbar substrate  112   b . Further, piers  132   g ,  132   h ,  132   i ,  132   j  extend downwardly from an interior, bottom surface of cover  124 , and are exemplary in shape and complimentary to positioning apertures  118   g ,  118   h ,  118   i ,  118   j  in busbar substrate  112   a.    
     Piers  132  can be of various shapes and configurations, with the shapes and configurations shown in FIG. 1 b  merely a non-limiting example. For example, with reference to FIGS. 4 and 5, as discussed previously, other pier assembly  130  configurations are shown, including a single pier  132 ′ and a pair of piers  132 ″. Further, while the pier assembly  130  configurations are shown with respect to lower case  122 , such pier assembly configurations are applicable to busbar substrates  112  as well. Again, the various pier shapes and configurations are exemplary and not limiting. 
     Each pier  132  is shaped to mate with a busbar substrate  112 , where the positioning apertures  118  receive the piers  132  to position a busbar substrate  112  relative another busbar substrate  112  or lower case  122 . The height of the piers  132  is similar to the height of the busbar substrate  112  having the positioning apertures  118 , whereby a top surface  134  of each pier  132  is generally planar with a top surface  113  of a busbar substrate  112 . By removing a busbar substrate  112  in the manufacture of the junction box  102  for a particular vehicle application, the top surface  134  of each pier  132  supports or maintains another busbar substrate assembly  110  at its proper position within the housing  120  through engagement with bottom surface  111  or top surface  113  of a particular busbar substrate  112 . Thus, should the circuitry provided on a particular busbar substrate  112  not be required, such a busbar substrate  112  can be eliminated when manufacturing the junction box  102  without alternative positioning of the remaining busbar substrate  112 . In this manner, noise and/or damage from a loosely-fit busbar substrate is eliminated and the added expense of including an otherwise unnecessary busbar substrate  112  to maintain spacing is avoided. 
     For the junction box  102 , any of the busbar substrates  112   a ,  112   b ,  112   c  can be removed while maintaining proper spacing in the junction box  102 . Further, it is possible to remove busbar substrate  112   a  and busbar substrate  112   c  and still maintain busbar substrate  112   b  in its proper position within junction box  102 , as best shown in FIG.  9 . With a different configuration of piers and apertures, it is possible to remove busbar substrate  112   a  and busbar substrate  112   b , and maintain the proper position of busbar substrate  112   c  in the junction box  102 . Similarly, another arrangement of piers and apertures allows removal of busbar substrates  112   b  and  112   c  and still maintains the proper position and spacing of busbar substrate  112   a . In sum, it is possible to modify the design to accommodate various configurations allowing versatility as required (e.g., adding downwardly extending piers from the bottom surface of busbar substrate  112   a  to align with and abut the upwardly extending piers from the bottom surface of the lower case  122 ). In designing such configurations, the alignment and misalignment of various piers and apertures allows the various configurations. 
     The junction box  102  is manufactured in a manner similar to junction box  2 , wherein the lower case  22  is grasped by a chuck print (not shown in the drawings) of an automated device in position relative to a positioning tool. If appropriate for a particular application, the busbar substrate  112   c  is grasped using the chuck of the automated device and positioning aperture  118   a ,  118   b ,  118   c ,  118   d  of busbar substrate  112   c  are aligned with piers  132   a ,  132   b ,  132   c ,  132   d , respectively, and positioned on lower case  122 . Because the piers  132   a ,  132   b ,  132   c  are inserted through positioning apertures  118   a ,  118   b ,  118   c ,  118   d , the busbar substrate  112   c  is reliably assembled and properly located on lower case  122 , as best shown in FIGS. 7 and 8. 
     Whether or not the busbar substrate  112   c  is required for a particular application (compare FIGS.  7  and  9 ), the busbar substrate  112   b  may be grasped and positioned using the chuck as described previously. If appropriate for a particular application, the busbar substrate  112   b  is grasped using the chuck of the automated device and piers  132   e ,  132   f  of busbar substrate  112   c , if present, are aligned with positioning apertures  118   e ,  118   f  of busbar substrate  112   b  ; otherwise, piers  132   a ,  132   b ,  132   c ,  132   d  of the lower surface of lower case  122  abut the bottom surface  111  of busbar substrate  112   b . Because the piers.  132   a ,  132   b ,  132   c ,  132   d  are either positioned through positioning apertures  118   a ,  118   b ,  118   c ,  118   d  or support the busbar substrate  112   b  via abutment with its bottom surface  113 , the busbar substrate  112   b  is reliably assembled and properly located on lower case  122 . As shown in FIG.7, busbar substrate  112   b  and busbar substrate  112   c  are both positioned within the housing  120 . 
     Whether or not the busbar substrate  112   b  is required for a particular application, the busbar substrate  112   a  may be grasped using the chuck of the automated device and aligned with and mounted in lower case  122 . If appropriate for a particular application, the busbar substrate  112   a  is grasped using the chuck of the automated device and piers  132   g ,  132   h ,  132   i ,  132   j  are aligned with positioning apertures  118   g ,  118   h ,  118   i ,  118   j  of busbar substrate  112   a . If busbar substrate  112   a  is not required for a particular application, the piers  132   g ,  132   h  abut the top surface  111  of busbar substrate  112   b . Because the piers  132   g ,  132   h ,  132   i ,  132   j  are either positioned through positioning apertures  118   g ,  118   h ,  118   i ,  118   j  or are supported on top surface  111  of busbar substrate  112   b , the busbar substrate  112   a  is reliably assembled and properly located in lower case  122 . 
     The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.