Abstract:
An electrical connector assembly includes a connector housing having a pair of interconnectable housing portions. Each housing portion has a terminal-receiving passage with a conductive terminal inserted thereinto. An opening in each housing portion communicates with the respective terminal-receiving passage thereof. A locking projection on each housing portion is insertable into the opening of the other housing portion to a position preventing withdrawal of the terminal of the other housing portion when the housing portions are interconnected.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention generally relates to the art of electrical connectors and, particularly, to an electrical connector assembly which incorporates an improved terminal position assurance (TPA) system that not only detects an incompletely inserted terminal but also locks a properly inserted terminal in its fully inserted position.  
         BACKGROUND OF THE INVENTION  
         [0002]    Generally, an electrical connector includes a dielectric housing mounting at least one electrically conductive terminal. The terminal is electrically connected to another circuit component, such as a discrete electrical wire. Connectors often are employed in mateable pairs such that each terminal and the housing of one connector are mateable with a corresponding terminal and the housing of a complementary mating connector.  
           [0003]    Electrical connector assemblies are used in a wide variety of applications where it is necessarily to electrically interconnect a plurality of electrical wires to perform various functions. The terminals of electrical connectors frequently are small components, such as terminals that are stamped and/or formed from thin sheet metal material. A poor quality electrical connection may occur if one (or more) terminal is not properly seated in its respective housing. The improper seating of a terminal in a housing may occur if the terminal is not fully inserted into the housing during the initial assembly of the connector or if the terminal is vibrated or pulled out of its fully seated condition during use of the connector. A pulling force on an electrical wire secured to a terminal may cause a temporary break in the electrical contact between the terminal and another terminal of the mating connector.  
           [0004]    More severe pulling forces on the electrical wire and/or the terminal may cause a partial or complete disconnection. In either event, even a momentary break in the electrical connection may result in spurious operation of an electrically driven device or an electrical circuit associated with the connector. Consequently, various locking structures have been used to lock terminals in their respective connector housings. Typically, the locking structure may include resilient tangs or latch projections which engage shoulders on the connector housing. Unfortunately, such resilient tangs or latch projections are prone to breakage. In addition, they do not detect or indicate whether or not a terminal is fully inserted and seated in the connector housing.  
           [0005]    To avoid these problems, it often is required to provide connectors with some form of a terminal position assurance (TPA) system to detect incomplete insertion of the terminals. In some applications, the TPA system or device also performs the function of locking the terminals in the connector housing.  
           [0006]    Heretofore, many TPA systems use separate TPA “keys” which are insertable into openings in the connector housing to detect full insertion of the terminals and to lock the terminals in their fully inserted positions. For dual row connector designs, a pair of TPA keys may be required. Such TPA keys create problems in that they require additional and costly manufacture and assembly. Separate TPA keys require additional components to be held in inventory. In addition, such TPA keys are prone to be lost or misplaced. Even if the TPA keys are tethered to the housing, such as by a living hinge, such TPA keys often are broken off from the tether or otherwise damaged. Regardless of whether the TPA keys are separate or tethered, they are inserted into the connector housing through an opening in the outer housing surface. These openings create further problems in electrical leakage and also may be dangerous for an operator during assembly and use.  
           [0007]    The present invention is directed to solving this myriad of problems by providing a unique TPA system which employs totally internal components within a multi-part connector housing.  
         SUMMARY OF THE INVENTION  
         [0008]    An object, therefore, of the invention is to provide an electrical connector assembly with a new and improved terminal position assurance (TPA) system.  
           [0009]    In the exemplary embodiment of the invention, the electrical connector assembly includes a connector housing having a pair of interconnectable housing portions. Each housing portion has a terminal-receiving passage. A conductive terminal is inserted into the passage of each housing portion. An opening is provided in each housing portion communicating with the respective terminal-receiving passage thereof. A locking projection on each housing portion is insertable into the opening of the other housing portion to a position preventing withdrawal of the terminal of the other housing portion when the housing portions are interconnected.  
           [0010]    As disclosed herein, the housing portions are hermaphroditic. Each housing portion has a pair of the openings on opposite sides of the respective terminal for receiving a pair of the locking projections of the other housing portion in positions on opposite sides of the terminal preventing withdrawal thereof.  
           [0011]    According to one aspect of the invention, each housing portion includes a flexible locking arm adjacent the opening in the respective housing portion. The flexible locking arm is engageable with a locking shoulder on the respective terminal. The locking projection on the other housing portion is insertable to a position behind the flexible locking arm to prevent the locking arm from moving out of engagement with the locking shoulder on the respective terminal.  
           [0012]    According to another aspect of the invention, the terminal in each housing portion includes a locking shoulder. The locking projection of the other housing portion is insertable to a position behind the locking shoulder to prevent withdrawal of the respective terminal.  
           [0013]    Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    The features of this invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with its objects and the advantages thereof, may be best understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements in the figures and in which:  
         [0015]    [0015]FIG. 1 is a perspective view of an electrical connector assembly according to the invention in conjunction with a complementary mating connector;  
         [0016]    [0016]FIG. 2 is a perspective view of the connector assembly according to the invention, taken at a different angle from that of FIG. 1;  
         [0017]    [0017]FIG. 3 is a perspective view of the two housing portions of the connector assembly disconnected from the assembled condition of FIGS. 1 and 2;  
         [0018]    [0018]FIG. 4 is a perspective view of one of the housing portions taken at a different angle from that of FIG. 3;  
         [0019]    [0019]FIG. 5 is a vertical section taken generally along line  5 - 5  of FIG. 2;  
         [0020]    [0020]FIG. 6 is a horizontal section taken generally along line  6 - 6  of FIG. 5;  
         [0021]    [0021]FIG. 7 is an exploded, fragmented perspective view of the TPA system for the signal terminals; and  
         [0022]    [0022]FIG. 8 is an enlarged, fragmented perspective view of one of the latches between the housing portions at each opposite side of the connector assembly. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0023]    Referring to the drawings in greater detail and first to FIGS. 1 and 2, the invention is embodied in an electrical connector assembly, generally designated  10 , which is mateable with a complementary mating connector, generally designated  12 . Connector assembly  10  terminates two pairs of signal wires or conductors  14  which are terminated to respective terminals (not visible in FIGS. 1 and 2) which electrically engage two pairs of signal terminals  16  mounted within mating connector  12 . Connector assembly  10  also terminates a pair of power wires or conductors  18  which are terminated to respective terminals (not visible in FIGS. 1 and 2) within connector assembly  10  and which electrically engage a pair of power terminals  20  mounted within mating connector  12 .  
         [0024]    Referring to FIG. 3 in conjunction with FIGS. 1 and 2, connector assembly  10  includes a dielectric composite housing, generally designated  22  (FIGS. 1 and 2), which is defined by a pair of interconnectable housing portions, generally designated  24 . As will be seen hereinafter, each housing portion  24  mounts respective terminals for termination to one of the pair of signal wires  14  and one of the pair of power wires  18 . In the preferred embodiment of the invention disclosed herein, housing portions  14  are hermaphroditic.  
         [0025]    With that understanding that housing portions  24  are hermaphroditic or substantially identical, only one of the housing portions will be described at this point, with particular reference to FIG. 4 in conjunction with FIG. 3. Specifically, each housing portion  24  includes a terminal-receiving passage  26  for receiving a power terminal, generally designated  28  and described in greater detail hereinafter, which is terminated to one of the power wires  18 . Each housing portion  24  is unitarily molded of dielectric material such as plastic or the like. The housing portion includes a pair of terminal-receiving passages  30  within which are mounted a pair of signal terminals, generally designated  32  and described in greater detail hereafter, which are terminated to one of the pair of signal wires  14 . Each housing portion has a pair of openings  34  which communicate with terminal-receiving passage  26  at opposite sides thereof. A pair of locking projections  36  on each housing portion is insertable into openings  34  of the other housing portion. In addition, each housing portion has a pair of openings  38  communicating respectively with the pair of terminal-receiving passages  30 . A pair of locking projections  40  on each housing portion are insertable into openings  38  of the other housing portion. Finally, each housing portion includes a flexible latch arm  42  on one side thereof and a latch boss  44  (FIG. 3) on the opposite side thereof. The latch boss is located within an L-shaped protective should  46 . The flexible latch arms and latch bosses will be described in greater detail hereinafter. Suffice it to say, the latch arm  42  of each housing portion is engageable with the latch boss  44  of the other housing portion in a hermaphroditic manner to latch and interconnect the housing portions and to define the composite housing  22  as seen in FIGS. 1 and 2.  
         [0026]    Referring to FIGS. 5 and 6, and particularly to FIG. 6, each power terminal  28  includes a crimp portion  50  which is crimped onto the outer dielectric cladding of the respective power wire  18 . The internal conductors  52  of the power wire are appropriately connected, as by soldering, to a base portion  54  of the power terminal. Each terminal also includes an upstanding or transversely oriented head portion  56  which abuts an internal shoulder  58  of housing portion  24  when the terminal and power wire are fully inserted and seated into terminal-receiving passage  26 . Each power terminal has a bifurcated contact end  60  for engaging one of the power terminals  20  (FIG. 1) of mating connector  12 .  
         [0027]    Still referring to FIGS. 5 and 6 and particularly FIG. 6, each housing portion  24  has a pair of flexible, hooked locking arms  62  which lockingly engage head portion  56  of the respective power terminal  28 . Power wires  18 , with power terminals  28  terminated thereto, are inserted into terminal-receiving passages  24  of housing portions  24  in the direction of arrows “A” (FIG. 6). During insertion, head portions  56  of the power terminals engage chamfered front ends  62   a  of locking arms  62  to spread the flexible locking arms outwardly until head portions  56  engage shoulders  58  of the housing portions. In this fully inserted or seated positions of the power terminals, flexible locking arms  62  snap back inwardly into locking positions as shown clearly in FIG. 6.  
         [0028]    Still referring to FIGS. 5 and 6, when the two hermaphroditic housing portions  24  are assembled or interconnected, locking projections  36  (FIG. 4) of each housing portion enter openings  34  of the other housing portion. When the housing portions are fully interconnected, locking projections  36  move into positions behind flexible locking arms  62  as seen in FIG. 6. Therefore, the flexible locking arms cannot flex outwardly out of engagement with head portions  56  of power terminals  28 . Consequently, locking projections  36  positively lock the terminals within the housing portions. In addition, should one of the power terminals  28  not be fully seated against the respective shoulder  58  of the housing portion, locking arms  62  will remain biased to outwardly spread positions. As a result, locking projections  56  cannot be moved completely into openings  34  because locking arms  62  will block movement of the locking projections. Consequently, this will indicate or detect an incomplete insertion of that respective power terminal.  
         [0029]    Referring to FIG. 7 in conjunction with FIG. 5, a pair of the signal terminals  32  are shown in their respective terminal-receiving passages  30  in one of the housing portions  24 . Each signal terminal  32  has a crimp portion  64  crimped to a respective one of the signal wires  14 . A front socket contact portion  64  of each signal terminal receives one of the signal terminals  16  (FIG. 1) of mating connector  12 . Each signal terminal also includes a locking shoulder  66  extending transversely outwardly therefrom. Locking shoulder  66  seats against a stop shoulder  67  on the respective housing portion to define a filly inserted position of the respective signal terminal. As clearly seen in FIG. 7, one of the locking projections  40  (also see FIG. 4) of the other housing portion  24  is shown positioned behind locking shoulder  66  of the signal terminal  32 . This is the condition when the two hermaphroditic housing portions are fully assembled or interconnected. In other words, during assembly, locking projections  40  of one housing portion moves into openings  38  in the other housing portion and into positions behind locking shoulders  66  of the signal terminals as seen in FIG. 7. Due to the configuration of the signal terminals, if one of the signal terminals is not fully inserted to its seated position, the respective locking projections will abut against the front socket portion  64  of the terminal whereupon the two housing portions cannot be fully engaged, thereby indicating or detecting the incorrect terminal position of that signal terminal.  
         [0030]    Referring to FIG. 8 in conjunction with FIGS. 2 and 5, it can be seen how each flexible latch arm  42  on each housing portion interengages the respective latch boss  44  of the other housing portion within L-shaped protective shroud  46 . During assembly or interconnection of the housing portions, a leading edge  42   a  of flexible latch arm  42  engages an angled or chamfered edge  44   a  of latch boss  44 , whereupon the flexible latch arm moves outwardly and then snaps back inwardly into latching engagement with the respective latch boss.  
         [0031]    It will be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.