Patent Publication Number: US-8992251-B2

Title: Electrical splice assembly

Description:
TECHNICAL FIELD OF INVENTION 
     The present invention relates to electrical splice assemblies for electrically connecting a plurality of electric cables. 
     BACKGROUND OF INVENTION 
     Splice assemblies are used, for example, in automotive applications in which a centralized connector is needed to connect one or more main cables to one or more branching cables. One such splice arrangement is known as an insulation displacement crimp (IDC) splice. United States Patent Application Publication No. US 2010/0029129 A1 to Cox et al. discloses an example of such an IDC splice. Cox et al. teaches that first and second wires are spliced using an electrically conductive IDC element which takes the form of an elongated U-shape. The IDC element includes a main base portion that connects first and second end portions. The first and second end portions each include a funnel or V-shaped wire reception slot that is configured to engage the wires that are to be spliced. In order to splice the first and second wires, the wires are forced into the respective V-shaped wire reception slot where insulation of the wires is displaced and the conductive core of the wires makes electrical contact with the IDC element, thereby placing the first wire in electrical communication with the second wire through the IDC element. IDC splice assemblies may be acceptable in some applications, however, some conductive core materials, for example aluminum, may not perform adequately in such IDC splice assemblies. Furthermore, IDC splice assemblies may not perform adequately in environments that are subjected to certain vibrations. 
     U.S. Pat. No. 5,901,441 to Kawamura et al. teaches another splice arrangement. Kawarmura et al. teaches that multiple wires are spliced by first stripping the insulation away from the ends of the conductors of each of the wires that are to be spliced. The exposed conductors are then subjected to an ultrasonic welding process to form the splice. This method of splicing is categorized as an off-line process and requires a separate station to complete. Consequently, the process may be time and cost intensive. 
     U.S. Pat. No. 7,980,872 to Smutny et al. teaches another splice arrangement. Smutny et al. teaches an insulative housing with a terminal receiving tray which receives a plurality of terminals. The terminals are held in place by a cover of the housing which is formed integrally with the housing. After all of the terminals are positioned in the receiving tray, the cover is closed, thereby retaining the terminals within the housing. A bus plate within the housing places the terminals in electrical communication with each other. This splice arrangement may require all of the terminals to be positioned within the housing before any of the terminals can be positively retained within the housing. 
     Other known splice assemblies may include multiple insulative bodies or housings which must be connected together. Such splice assemblies that include multiple insulative bodies or housings may be time and cost intensive. 
     What is needed is a splice assembly which minimizes or eliminates one or more of the shortcomings as set forth above. 
     SUMMARY OF THE INVENTION 
     Briefly described an electrical splice assembly is provided for placing a plurality of wires in electrical communication. The electrical splice assembly includes an insulative housing extending along an axis and having a forward portion, a rearward portion, and an intermediate portion between the forward portion and the rearward portion. The intermediate portion defines a plurality of axially extending terminal retention cavities. A conductive bus plate is retained within the forward portion of the housing. A plurality of conductive terminals each extend into a respective one of the plurality of terminal retention cavities and are each in electrical contact with the bus plate. Each of the terminal retention cavities is defined by 1) a pair of opposing sidewalls connected to the forward portion and to the rearward portion and 2) a pair of opposing retention beams. The retention beams each include a latch which engages a respective one of the plurality of terminals to retain the terminals in the terminal retention cavities. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       This invention will be further described with reference to the accompanying drawings in which: 
         FIG. 1  is an isometric exploded view of an electrical splice assembly in accordance with the present invention; 
         FIG. 2  is an isometric exploded view of the electrical splice assembly in accordance with the present invention taken from a different perspective than the isometric exploded view of  FIG. 1 ; 
         FIG. 3  is cross-section view of the electrical splice assembly in accordance with the present invention; 
         FIG. 4  is an end view of a housing of the electrical splice assembly in accordance with the present invention; 
         FIG. 5  is a cross sectional view of the housing of the electrical splice assembly in accordance with the invention taken through section line  5 - 5  of  FIG. 2 ; and 
         FIGS. 6-10  show an assembly progression of the electrical splice assembly in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF INVENTION 
     Referring now to the drawings wherein like reference numerals are used to identify identical components in the various views,  FIGS. 1-5  illustrate an exemplary electrical splice assembly  10 . Electrical splice assembly  10  includes an electrically insulative housing  12  extending along a housing axis  14 , a conductive bus plate  16 , and a plurality of conductive terminals  18  that are attached to respective exposed ends of insulated electric cables  20 . Bus plate  16  provides electrical communication between terminals  18 , and consequently, each electric cable  20  is in electrical communication with the other electric cables  20 . 
     Bus plate  16  includes an elongated strip  22  with a plurality of blades  24  extending therefrom. Blades  24  are coplanar with strip  22  and each blade  24  extends in substantially the same direction from strip  22  in the direction of housing axis  14 . 
     Housing  12  includes a forward portion  26  defining a bus plate retainer  28 , an intermediate portion  30  defining a plurality of longitudinally extending terminal retention cavities  32 , and a rearward portion  34  defining terminal retention cavity entrances  36 . 
     Bus plate retainer  28  is defined by opposing housing sidewalls  38  which extend axially the length of housing  12  from forward portion  26  to rearward portion  34 . Bus plate retainer  28  is also defined by opposing bus plate retainer walls  40 ,  42  which span between housing sidewalls  38 . Bus plate retainer walls  40 ,  42  extend axially and terminate at intermediate portion  30 . A partition  44  terminates bus plate retainer  28  at terminal retention cavities  32 . Partition  44  may be substantially perpendicular to housing axis  14  and includes a plurality of interior partition apertures  46  extending axially through partition  44  and a plurality of exterior partition apertures  47  extending axially through partition  44 . Each interior partition aperture  46  provides communication between bus plate retainer  28  and a respective one of terminal retention cavities  32 . Interior partition apertures  32  are each sized to allow a respective one of blades  24  to extend axially therethrough into a respective terminal retention cavity  32  to mate with a respective terminal  18  as will be described in greater detail later. Bus plate retainer  28  may be sized to receive bus plate  16  in a press fit relationship in order to prevent unintended removal of bus plate  16  from bus plate retainer  28 . 
     The inside surface of bus plate retainer wall  40  includes interior grooves  48  which extend axially into forward portion  26 . Each interior groove  48  is axially aligned with a respective terminal retention cavity  32 . Each interior groove  48  is also axially aligned with a portion of a respective interior partition aperture  46  as will be described in greater detail later. The inside surface of bus plate retainer wall  42  may be substantially planar and terminates at partition  44 . The outside surface of bus plate retainer wall  42  includes exterior grooves  50  which extend axially along forward portion  26 . Each exterior groove  50  is axially aligned with a respective terminal retention cavity  32 . Each exterior groove  50  communicates with a respective terminal retention cavity  32  through a respective exterior partition aperture  47 . 
     Intermediate portion  30  is defined in part by housing sidewalls  38  which extend axially the length of housing  12  from forward portion  26  to rearward portion  34 . Housing sidewalls  38  together with a plurality of interior sidewalls  52  partly define terminal retention cavities  32 . Interior sidewalls  52  are equally spaced between housing sidewalls  38  and extend axially from rearward portion  34  to partition  44  in a direction that is substantially parallel to housing sidewalls  38 . Intermediate portion  30  and terminal retention cavities  32  are also partly defined by a plurality of first retention beams  54  and a plurality of second retention beams  56  which are opposed to first retention beams  54 . First retention beams  54  and second retention beams  56  extend axially from forward portion  26  to rearward portion  34  and are attached only at forward portion  26  and rearward portion  34 , i.e. first retention beams  54  and second retention beams  56  are not attached to housing side walls  38  and interior sidewalls  52  along at least a portion of intermediate portion  30  which may be best seen in  FIG. 5 . First retention beams  54  and second retention beams  56  are substantially perpendicular to housing sidewalls  38  and interior sidewalls  52 , thereby giving terminal retention cavities  32  a substantially rectangular or square cross-sectional shape when cut by a plane that is substantially perpendicular to housing axis  14 . An axially extending slot is defined between each adjacent first retention beam  54  and an axially extending slot is also defined between each adjacent second retention beam  56 . First retention beams  54  and second retention beams  56  are compliant and resilient as will be described in greater detail later. 
     First retention beams  54  each have a first latch  58  that extends from first retention beam  54  into terminal retention cavity  32 . First latch  58  includes a first latch ramp portion  60  which faces toward rearward portion  34  and which is oblique to housing axis  14 . First latch  58  also includes a first latch shoulder portion  62  which faces toward forward portion  26  and which is substantially perpendicular to housing axis  14 . Each first latch  58  is axially aligned with a respective one of interior partition apertures  46 . Each first latch  58  is used to retain a respective terminal  18  in a respective terminal retention cavity  32  as will be described in greater detail later. 
     Second retention beams  56  each have a second latch  64  that extends from second retention beam  56  into terminal retention cavity  32 . Second latch  64  includes a second latch ramp portion  66  which faces toward rearward portion  34  and which is oblique to housing axis  14 . Second latch  64  also includes a second latch shoulder portion  68  which faces toward forward portion  26  and which is substantially perpendicular to housing axis  14 . Each second latch  64  is axially aligned with a respective one of exterior partition apertures  47 . Each second latch  64  is used to retain a respective terminal  18  in a respective terminal retention cavity  32  as will be described in greater detail later. 
     Terminal retention cavity entrances  36 , which are defined by rearward portion  34 , extend axially through rearward portion  34 . Each terminal retention cavity entrance  36  provides access to a respective terminal retention cavity  32 . 
     Each terminal  18  has a box-shaped mating portion  72  and a crimp section  74 . The axial end of mating portion  72  distal from crimp section  74  has a receptor  76  configured to receive a respective blade  24  of bus plate  16  therein. One side of mating portion  72  includes an opening therein defining a first terminal shoulder  78  while the axial end of mating portion  72  proximal to crimp section  74  defines a second terminal shoulder  80 . The opening defining first terminal shoulder  78  is sufficiently large to receive first latch  58  therein. Crimp section  74  is configured to be crimped to electric cable  20  to provide electrical communication from a conductive core  82  of electric cable  20  to terminal  18 . 
     Reference will now be made to  FIGS. 6-10  which show a progression of assembly of electrical splice assembly  10 . In  FIG. 6 , terminal  18  is shown axially inserted into terminal retention cavity entrance  36  just prior to terminal  18  coming into contact with second latch  64 . In  FIG. 7  terminal  18  is shown advanced part way into terminal retention cavity  32  such that mating portion  72  of terminal  18  has advanced over second latch ramp portion  66 , thereby causing second retention beam  56  to flex resiliently outward from terminal retention cavity  32 . In  FIG. 8 , terminal  18  is shown advanced further into terminal retention cavity  32  than in  FIG. 7  such that mating portion  72  of terminal  18  has advanced over first latch ramp portion  60 , thereby causing first retention beam  54  to flex resiliently outward from terminal retention cavity  32 . As can be seen, second retention beam  56  remains flexed resiliently outward from terminal retention cavity  32 . In  FIG. 9 , terminal  18  is shown fully inserted into terminal retention cavity  32 . When this happens, first latch  58  is aligned with the opening which defines first terminal shoulder  78 , thereby allowing first retention beam  54  to snap inward such that first terminal shoulder  78  engages first latch shoulder portion  62  to prevent removal of terminal  18  from terminal retention cavity  32 . Simultaneously, second latch  64  passes over the axial end of mating portion  72  that defines second terminal shoulder  80 , thereby allowing second retention beam  56  to snap inward such that second terminal shoulder  80  engages second latch shoulder portion  68  to prevent removal of terminal  18  from terminal retention cavity  32 . While the insertion of one terminal  18  has been described, the process is the same for each terminal  18 . Furthermore, since each first retention beam  54  and second retention beam  56  of a respective terminal retention cavity  32  operates independently of every other first retention beam  54  and second retention beam  56  of respective terminal retention cavities  32 , each terminal  18  may be inserted either separately or simultaneously without having a terminal  18  being inadvertently removed from its respective terminal retention cavity  32 . 
     In  FIGS. 3 and 10 , bus plate  16  is shown fully inserted into bus plate retainer  28  such that blades  24  pass through respective interior partition apertures  46  into respective receptors  76  of terminals  18 . In this way, bus plate  16  provides electrical communication between each electric cables  20 . While bus plate  16  has been describe as being positioned after terminals  18  are positioned, it should be understand that this order may be reversed. 
     Housing  12  is easily molded by a plastic injection molding process using mold halves (not shown) without the need for slides. This ease of molding is permitted due to first latch  58  being axially aligned with interior partition apertures  46  and interior grooves  48 , thereby allowing features of a first mold half that form a portion of first latch  58  to be withdrawn axially through interior partition apertures  46  and interior grooves  48  upon completion of the plastic injection molding process. This ease of molding is also permitted due to second latch  64  being axially aligned with exterior partition apertures  47  and exterior grooves  50  which allows the first mold half that forms a portion of second latch  64  to be withdrawn axially through exterior partition apertures  47  and exterior grooves  50  upon completion of the plastic injection molding process. 
     While this invention has been described in terms of preferred embodiments thereof, it is not intended to be so limited, but rather only to the extent set forth in the claims that follow.