Patent Publication Number: US-7909638-B2

Title: Electrical connector assembly having connector position assurance device

Description:
TECHNICAL FIELD 
     The present invention relates to an electrical connector assembly. In particular, it relates to an electrical connector assembly having a Connector Position Assurance (CPA) device. 
     BACKGROUND 
     In certain industrial applications, electrical connectors are required to be securely connected to each other. These electrical connecter are typically provided with locking features such as latches to lock the connector housings to each other. In addition, a Connector Position Assurance (CPA) device is provided to lock the locking members as an additional locking assurance. 
     When a connector is connected to a counterpart connector and that the latches are engaged to each other, the CPA device is installed to the connector assembly at a final locking position to lock the latches, so as to secure the locking status of the connectors. However, the CPA device may be placed to the final locking position before the two connectors are connected, which may cause difficulties and/or inconvenience to connect the two connectors correctly. 
     There is therefore a need to provide a connector assembly with a CPA device which can be installed and shipped together with one of the connectors. The CPA device is fixed to the connector housing in a pre-locking position and will not move to the final locking position until the two mating connectors are mated together and require locking security assurance function by the CPA device. 
     SUMMARY OF INVENTION 
     Embodiments of the present invention provide an electrical connector assembly having a first connector and a second connector to be mated together, and a Connector Position Assurance (CPA) device installed on one of the first and second connectors. The CPA device is fixed to a pre-lock position when shipped together with said one of the connectors and before the first and second connectors are mated. At the pre-lock position, a locking lever on the second connector can be deformed so that primary locking members of the first and second connectors can be engaged. When the first and second connectors are mated, a rib formed on the first connector acts against a release member provided on the CPA device, to allow the CPA device to move to a final lock position. At the final-lock position, a secondary locking member of the CPA device restricts the movement of the primary locking member of the second connector, so as to prevent the primary locking members from being disengaged. 
     Other aspects and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the inventive concept of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other aspects and advantages of the present invention will be described in detail with reference to the accompanying drawings, in which: 
         FIG. 1A  is a schematic perspective view showing an electrical connector assembly according to one embodiment of the present invention. 
         FIG. 1B  is a schematic perspective view showing a first connector of the connector assembly shown in  FIG. 1A . 
         FIG. 1C  is a schematic perspective view showing a second connector of the connector assembly shown in  FIG. 1A , with a CPA device coupled thereon. 
         FIG. 2  is a schematic perspective view showing a CPA device of a connector assembly shown in  FIG. 1A . 
         FIG. 3A  is a partial cross-sectional side view of  FIG. 1C   
         FIG. 3B  is a partial top view of  FIG. 1C . 
         FIG. 3C  is a partial cross-sectional top view of  FIG. 3A . 
         FIG. 3D  is a partial cross-sectional side view showing the two connectors are mated and the CPA device is at the pre-lock position. 
         FIG. 4A  is a partial perspective cross-sectional view showing a connector assembly of  FIG. 1A  when the CPA device is at the pre-lock position. 
         FIG. 4B  is a partial perspective top view of  FIG. 4A . 
         FIG. 5A  is a partial cross-sectional perspective view showing a connector assembly of  FIG. 1A  when the CPA device is at the final-lock position. 
         FIG. 5B  is a partial cross-sectional side view of  FIG. 5A . 
         FIG. 5C  is a partial cross-sectional top view of  FIG. 5A . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As shown in  FIG. 1A , an electrical connector assembly  10  according to one embodiment of the present invention has a first connector  100 , a second connector  200 , both shown as connector housings, which can be mated to each other, and a Connector Position Assurance (CPA) device  300  moveably coupled to second connector housing  200 . Compartments  201  are provided on second connector housing  200 , into which contact terminals (not shown) are placed. CPA device  300  is slidable relative to second connector housing  200  along forward/backward directions  12  and  14 . 
       FIG. 1B  shows first connector housing  100  of connector assembly  10  shown in  FIG. 1A . First connector housing  100  has side walls  102  surrounding a cavity  104 . A first latch member  118  and a pair of ribs  114 ,  116  are formed on top side wall  102   a  and protruding inward into cavity  104 . 
       FIG. 1C  shows second connector housing  200  of connector assembly  10  shown in  FIG. 1A . Second connector housing  200  has a pair of guiding rails  220 ,  230  along which CPA device  300  is slidably coupled to second connector housing  200 . Second connector housing  200  has a locking lever  204  formed integral from a base portion  202 , with a second latch member  218  and a release button  206  structured such that, when release button  206  is pressed, locking lever  204  and second latch member  218  can be elastically deformed towards base portion  202 . 
       FIG. 2  shows CPA device  300  in further detail. CPA device  300  is formed of an integral part, by molding for example. CPA device  300  has a base portion  302 , a center prong  310  extending forwardly and perpendicularly from base portion  302 , in a cantilevered manner. First and second arms  320 ,  330  extend forwardly and perpendicularly from base portion  302  and at each side of center prong  310 . At a front end portion  318  of center prong  310 , away from base portion  302  and slightly raised from center prong  310 , there is formed a step  312  facing forward direction  12 , and a pair of lateral prongs  314 ,  316  extending perpendicularly from front end  318  of center prong  310 . Two additional projections  340  and  350  may also be formed on base  302 . 
     Formed on a side of first arm  320  there are first pre-lock protrusions or lugs  324 ,  326  and first final-lock protrusion or lug  328 . Likewise, second pre-lock protrusions or lugs  334 ,  336  and second final-lock protrusion or lugs  338  are formed on a side of second arm  330 . 
       FIG. 3A  is a partial cross-sectional side view, along a longitudinal section depicted by A-A in  FIG. 1C . Before first and second connector housings  100  and  200  are mated, CPA device  300  is coupled to second connector housing  200 , in a pre-lock position. At the pre-lock position, a stopper  212  formed on locking lever  204  and step  312  of CPA device  300  face each other by which, stopper  212  blocks CPA device  300  from moving further towards front direction  12 . In addition, as shown in  FIGS. 3B and 3C , first pre-lock lugs  324 ,  326 ,  334  and  336  of CPA device  300  engage with respective steps  224 ,  234  and lateral protrusions  226 ,  236  of second connector housing  200 . By virtue of these engagements, CPA device  300  is prevented from moving along backward direction  14 . CPA device  300  can now be fixed to second connector housing  200  at the pre-lock position. This allows the second connector to be manufactured and shipped together with a CPA device fixed to the pre-lock position. This configuration can prevent the CPA device from being placed apart from the second connector, and missing of the CPA device can be avoided. 
     At the pre-lock position, as shown in  FIG. 3A , there remains a gap  208  between second latch member  218  and base portion  202  of second connector housing  200 . Second latch member  218  can therefore be allowed to move downward, when press button  206  is pressed. As such, the CPA device will not be misplaced to affect mating of the first and second connectors. 
     When first and second connector housings  100  and  200  are to mate with each other, press button  206  is pressed downward, causing second latch member  218  to move downward. This will allow second latch member  218  to pass underneath first locking projection  118 . When press button  206  is released, locking lever  204  springs back, and second latch member  218  to act against first latch member  118 . First and second connector housings  100  and  200  can therefore be locked to each other by the engagement of first and second latch members  118  and  218 , as shown in  FIG. 3D . 
     Mating of first and second connector housings  100  and  200 , i.e. when second connector housing  200  is inserted into cavity  204 , ribs  114  and  116  of first connector housing  100  urge against lateral prongs  314 ,  316  of CPA device  300 , as shown in  FIGS. 4A and 4B . Ribs  114  and  116  therefore press lateral prongs  314  and  316  downward. Accordingly, center prong  310  is deflected with front end  318  brought downward, causing step  312  to move away from the blockage of stopper  212 . This allows CPA device  300  to move further along forward direction  12 , and with front end  318  placed within the clearance gap  208 , i.e., between second latch member  218  and base portion  202  of second connector housing  200 . By placing front end  318  between second protrusion  218  and base portion  202 , CPA device  300  is moved to a final-lock position. 
     As shown in  FIGS. 5A ,  5 B and  5 C, at the final-lock position, additional projections  340 ,  350  (only one additional projection  350  is shown in  FIGS. 5A and 5B ) are placed underneath press button  206  of second connector housing  200 . Downward movement of second locking protrusion  218  is therefore prevented by front end  318 . In addition, downward movement of press button  206  is prevented by additional protrusions  340  and  350 . Accordingly, disengagement of first and second latch members  118  and  218  is prevented, hence first and second connector housings  100  and  200  are securely locked to each other. 
     When CPA device  300  is at the final-lock position, as shown in  FIG. 5C , first and second final lock lugs  328  and  338  act against lateral protrusions  226  and  236  of second connector housing  200 . By this engagement, CPA device  300  is fixed to second connector  200  at the final lock position. 
     Although embodiments of the present invention have been illustrated in conjunction with the accompanying drawings and described in the foregoing detailed description, it should be appreciated that the invention is not limited to the embodiments disclosed, and is capable of numerous rearrangements, modifications, alternatives and substitutions without departing from the spirit of the invention as set forth and recited by the following claims.