Abstract:
A sealed electrical connector assembly is provided having a connector position assurance device (CPA) including at least one CPA support rail and a CPA latch finger. A plug housing is provided with a body section having a mating interface on one end thereof that retains a plurality of plug contacts. The plug housing includes a shroud extending about at least a portion of the body section and is spaced apart from the body section by a predefined gap. A header is provided having a base retaining a plurality of header contacts adapted to electrically engage the plug contacts. The header includes walls defining a plug receptacle adapted for receiving the mating interface. The walls are received in the gap between the shroud and the body section of the plug housing. A seal is mounted to one of the plug housing end header to form a hermetic seal between the plug housing and header when fully mated with one another. A CPA retention assembly is mounted to at least one of the plug housing and header. The CPA is slidably mounted to the CPA retention assembly and moveable between a retracted position and a locked position. The CPA permits engagement and disengagement of the header and plug when in the CPA retracted position and prevents engagement and disengagement of the header plug assembly when in the CPA locked position.

Description:
BACKGROUND OF THE INVENTION 
     The preferred embodiments of the present invention generally relate to a sealed electrical connector assembly that includes a connector position assurance device (CPA) for assuring that matable connectable halves, such as a header and plug, are fully mated with one another. 
     Connector devices have been proposed that provide electrical terminals having matable male to female connector halves. One of the male and female connector halves includes a resilient, extended lock arm that locks behind a bar on the complementary connector half. When the connector halves are mated, a CPA and an assist device are inserted along a track. The CPA includes resilient, releasable lock tabs to retain it in engagement with the connectors. The CPA device provides a means to assure that the male and female connectors are fully mated. 
     U.S. Pat. No. 5,643,003 discloses a connector assembly including a plug housing and a header. The plug housing includes a housing latch formed thereon that includes grooves for slidably receiving a connector position assurance device (CPA). The CPA is inserted from a mating side face of the plug housing and is movable from a first position to a final position only when the header is filly mated to the plug housing. The CPA includes a deflectable beam and an embossment. The beam is deflected below projections of a latch on the header as the CPA is moved into its final position. When the CPA is in its final position, the operator can readily observe that the plug housing has been fully mated to the header. Additionally, a deflecting force which, when applied to the header latch, causes the header latch to deflect relative to the receptacle housing. The deflecting force will also cause the CPA to be displaced relative to the plug housing when the CPA is in the first position. 
     However, the connector assembly of the &#39;003 patent is not readily adaptable to electrical connectors that require a seal or utilize shrouds. For example, the header latch of the &#39;003 patent extends through the area that otherwise would be used for sealing, and prevents adequate sealing. 
     It is a n object of at least one preferred embodiment of the present invention to overcome the above-noted and other disadvantages of conventional connectors. 
     BRIEF SUMMARY OF THE INVENTION 
     At least one preferred embodiment of the present invention is provided including a sealed electrical connector assembly having a connector position assurance device (CPA) including at least one CPA support rail and a CPA latch finger. The plug housing includes a body section with a mating interface on one end thereof. The mating interface retains a plurality of plug contacts. The plug housing further includes a shroud extending about at least a portion of the body section. The shroud is spaced apart from the body section by a gap. A header includes a base retaining a plurality of header contacts adapted to electrically engage the plug contacts. The header includes walls that define a plug receptacle adapted for receiving the mating interface. The walls are received in the gap between the shroud and body section of the plug housing. A seal is mounted to one of the plug housing and header to form a hermetic seal between the plug housing and header when the plug housing and header are fully mated with one another. The electrical connector assembly further includes a CPA retention assembly mounted to at least one of the plug housing and header. The CPA is slidably mounted to the CPA retention assembly and movable between a retracted position and a locked position. The CPA permits engagement and disengagement of the header and plug housing when in the retracted position and prevents engagement and disengagement of the header and plug assembly when in the locked position. 
     In accordance with at least one alternative embodiment, the CPA further comprises at least one rail support having a groove therein and the CPA latch assembly comprises at least one rail slidably received within the groove to guide the CPA between the retracted and locked positions. 
     In accordance with at least one alternative embodiment, the shroud surrounds a perimeter of the plug housing to define a peripheral gap about the seal. The gap accepts top, bottom and sidewalls of the header to form a hermetic seal between the body section and the header . The header includes a CPA reset embossment on one wall which engages the CPA, and resets it to the retracted position, when the CPA is in the locked position before the plug housing and header are fully mated with one another. 
     In accordance with at least one alternative embodiment, the plug housing includes top, bottom and sidewalls defining the mating interface of the body section, while the header comprises top, bottom and sidewalls defining the opening. The walls of the plug housing and header form a hermetic contact with the seal when the header and plug housing are fully mated. 
     Optionally, the CPA retention assembly may be mounted to the shroud. As a further option, a deflectable latch beam may be mounted at an intermediate point along the latch beam to the plug housing. The header may include a latch mating element that engages one end of the latch beam when the plug housing and header are fully mated. 
     Optionally, the seal may be mounted to a perimeter of the body section of the plug housing and walls of the header may cooperate with the seal to form a sealed interface with the body section when fully mated. Optionally, the CPA retention assembly may include a header rail and a latch rail. The header rail may be mounted to a wall of the header and the latch rail may be mounted to the shroud. The header rail and latch rail are aligned when the housing plug and header are fully mated to permit the CPA to move from the retracted position to the locked position. 
     In accordance with at least one alternative embodiment of the present invention, an electrical connector is provided comprising a connector position assurance device (CPA) having a CPA guideway and a CPA retention lever. A first connector housing and a second connector housing are provided having first and second connector interfaces, respectively, containing contacts that are joined when the first and second connectors are mated with one another. A latch assembly is provided having a first latch guideway adapted to slidably join the CPA guideway to permit the CPA to be moved from a retracted position to a locked position. The latch assembly further includes a latch engagement surface. A latch mating element may be located on one of the first and second connector housings to securely engage the latch engaging surface of the latch assembly when the first and second housings are fully mated. The latch mating element may include a second latch guideway adapted to slidably join the CPA guideway to retain the CPA in its retracted position. A seal is mounted to on e of the first and second connector housings to for m a hermetic seal between the first and second connector housings when fully mated. 
     In accordance with at least one alternative embodiment, a shroud is mounted to the first connector housing and arranged to surround the second connector housing when the first and second connector housings are fully mated. Optionally, the first and second latch guideways may include rails and the CPA guideway may include a groove that accepts the rails. Optionally, the first and second connector housings may each include top, bottom and sidewalls defining the first and second connector interfaces that are hermetically sealed to one another by the seal when fully mated. Optionally, the latch assembly may be formed on a shroud surround the first and connector housing. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 illustrates an isometric view of a sealed electrical connector housing assembly formed in accordance with a preferred embodiment of the present invention. 
     FIG. 2 illustrates an isometric front view of a plug housing formed in accordance with a preferred embodiment of the present invention. 
     FIG. 3 illustrates an isometric rear view of a plug housing formed in accordance with a preferred embodiment of the present invention. 
     FIG. 4 illustrates a top plan view of a plug housing formed in accordance with a preferred embodiment of the present invention. 
     FIG. 5 illustrates a rear view of a plug housing formed in accordance with a preferred embodiment of the present invention. 
     FIG. 6 illustrates a front view of a plug housing formed in accordance with a preferred embodiment of the present invention. 
     FIG. 7 illustrates an isometric front view of a header formed in accordance with a preferred embodiment of the present invention. 
     FIG. 8 illustrates an isometric rear view of a header formed in accordance with a preferred embodiment of the present invention. 
     FIG. 9 illustrates a top plan view of a header formed in accordance with a preferred embodiment of the present invention. 
     FIG. 10 illustrates a front view of a header formed in accordance with a preferred embodiment of the present invention. 
     FIG. 11 illustrates a sectional view of a cut-out portion of a header taken along line  11 — 11  in FIG. 9 formed in accordance with a preferred embodiment of the present invention. 
     FIG. 12 illustrates an isometric front view of a connector position assurance device (CPA) formed in accordance with a preferred embodiment of the present invention. 
     FIG. 13 illustrates an isometric rear view of a CPA formed in accordance with a preferred embodiment of the present invention. 
     FIG. 14 illustrates a front view of a CPA formed in accordance with a preferred embodiment of the present invention. 
     FIG. 15 illustrates a sectional view taken along line  15 — 15  in FIG. 12 of a CPA formed in accordance with a preferred embodiment of the present invention. 
     FIG. 16 illustrates a sectional view of a sealed electrical connector assembly with a CPA in the retracted position formed in accordance with a preferred embodiment of the present invention. 
     FIG. 17 illustrates a sectional view of a sealed electrical connector assembly with a CPA in the locked position formed in accordance with a preferred embodiment of the present invention. 
     FIG. 18 illustrates a sectional view of a sealed electrical connector assembly with a CPA in the retracted position formed in accordance with a preferred embodiment of the present invention. 
     FIG. 19 illustrates a sectional view of a sealed electrical connector assembly with a CPA in the locked position formed in accordance with a preferred embodiment of the present invention. 
     The foregoing summary, as well as the following detailed description of the preferred embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings, embodiments which are presently preferred. It should be understood, however, that the present invention is not limited to the precise arrangements and instrumentality shown in the attached drawings. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 illustrates an isometric view of a sealed electrical connector housing assembly  10  that comprises first and second housings. In the illustrated embodiment of FIG. 1, these two housings are a plug housing  12  and a header  18 . The plug housing  12  comprises a front end  14  and a rear end  16 . The rear end  16  receives wires (not shown). The header  18  includes front end  20  and rear end  22 . The front end  14  of the plug housing  12  mates with the front end  20  of the header  18 . The rear end  22  of the header  18  receives a grid of wires arranged in rows and columns. The wires may be bent at a 90° angle downward to be connected to another element (not shown). 
     FIGS. 2 and 3 illustrate front and rear isometric views of the plug housing  12 . FIG. 4 illustrates a plan view of the plug housing  12 , FIG. 5 illustrates a rear view, and FIG. 6 illustrates a front view of the plug housing  12 . The plug housing  12  includes a shroud  32  surrounding an internal body section  31 . The body section  31  includes a mating interface  30  having a plurality of apertures  29  therein arranged in rows and columns. Each aperture retains a plug contact  39  that is connected at one end to wires (not shown) leading from the rear end  16 . In the embodiment of FIG. 1, the internal body section  31  is divided into upper and lower portions  35  and  37 , each of which retains at least one row of contacts  39  in apertures  29 . The internal body section  31  includes a top wall  24 , bottom wall  26  and sidewalls  28 . The outer peripheral surface of the internal body section  31  is spaced a distance  41  from the interior surface of the shroud  32 . The outer peripheral surface of the top wall  24 , bottom wall  26  and sidewalls  28  of the internal body section  31  is enclosed by a rubber seal  34 . The seal  34  frictionally engages an interior surface of the header  18  to form a hermetic seal between the peripheral surface of the internal body section  31  and the interior of the header  18 . 
     The shroud  32  may include one or more grooves  33  extending from the front end  14  along the interior surface of the shroud  32 . The grooves  33  receive corresponding ribs  59  located on the exterior walls of the header  18 . The grooves  33  and ribs  59  cooperate to ensure proper orientation between the plug housing  12  and header  18  before mating. 
     A latch assembly  43  fastens the plug housing  12  and header  18  when mated to one another. The latch assembly  43  comprises a deflectable latch beam  36  mounted to the shroud  32  at a point proximate the center of the latch beam  36  through a vertical post extending upward from the shroud  32 . The deflectable latch beam  36  is normally biased in a substantially horizontal position. However, the deflectable latch beam  36  may be deflected under an imposed force in either direction in a “see-saw” manner. The deflectable latch beam  36  is composed of a resilient material such that it will return to substantially its original position once the imposed force is removed. A latch engaging surface  38  is located on the underside of the front portion  37  of the deflectable latch beam  36 . The latch engaging surface  38  includes a ramped portion  48 , a flat portion  49 , and a latching portion  50 , best seen in FIG.  17 . The deflectable latch beam  36  also comprises a latch rail  40  extending along the side of the deflectable latch beam  36 . The latch rail  40  is configured for slidable contact with the rail surface  88  of the CPA  82 . The illustrated embodiment comprises two latch engaging surfaces  38  and two latch rails  40 . Preferably, a finger stop  42  is also included on the deflectable latch beam  36 . The finger stop is located proximate the center of the deflectable latch beam. The deflectable latch beam  36  may further comprise a stopping portion  41  located proximate and interior to the latch rails  40 , best seen in FIG.  17 . The embodiment illustrated features a finger stop  42  comprising a channel  44  and ears  46 . The channel  44  extends down the center of the deflectable latch beam  36 , with two ears  46  opposing each other on opposite sides of the channel  44 . 
     FIGS. 7 and 8 illustrate isometric views of the header  18 . The header  18  has an opening  58  configured to receive the mating interface  30  of the plug housing  12 . The illustrated header features two openings  58 . The header  18  includes a base plate  51  with a pair of hollow receptacles  53  formed on one side thereof. Each receptacle  53  includes a top wall  52 , bottom wall  54  and sidewalls  56 . The top wall  52 , bottom wall  54 , and sidewalls  56  define the opening  58 . Preferably, the header  18  may include one or more ribs  59  located along the outside of one or more of top wall  52 , bottom wall  54  and sidewalls  56 . The ribs  59  are located and configured to be accepted by grooves  33  of the plug housing  12  to insure proper alignment of the plug housing  12  and header  18  when they are brought together for mating. In the illustrated embodiment, two ribs  59  on opposite sidewalls  56  cooperate with two grooves  33  located on the shroud  32  for alignment purposes. The location of grooves  33  and ribs  59  can also be varied for similarly sized connector assemblies to prevent connecting a plug housing to an incorrect header. 
     FIG. 9 illustrates a plan view of the header  18 , while FIG. 10 illustrates a front view and FIG. 11 illustrates a sectional view of the header  18 . The header  18  includes a latch mating element  60  located on one or more of the walls  52 ,  54  and  56 . The latch mating element  60  of the illustrated embodiment in turn comprises a ramped surface  62 , a flat portion  64 , and a vertical portion  66 . The ramped surface  62  inclines from the front end  20  to the rear end  22  of the header  18 . The flat portion  64  is substantially horizontal, and the vertical portion  66  is substantially vertical and located proximate the rear end  22 . The latch mating element  60  cooperates with the latch engaging surface  38  of the deflectable latch beam  36  in the illustrated embodiment to secure the plug housing  12  and header  18  when properly mated. The following sequence of events occurs as the plug housing  12  and header  18  are urged together. 
     As the plug housing  12  and header  18  are brought together, the internal body section  31  is received in the opening  58  with the walls  52 ,  54  and  56  fit between the body section  31  and shroud  32 . The grooves  33  and ribs  59  cooperate to assure proper alignment. As the plug housing  12  and header  18  are further urged together, the latch engaging surface  38  comes into contact with the latch mating element  60 . More specifically, the ramped portion  48  of the latch engaging surface  38  comes into contact with the ramped surface  62  of the latch mating element  60 . Upon further urging, the ramped portion  48  and ramped surface  62  begin to slide along each other. This motion causes the front portion  37  of the deflectable latch beam  36  to articulate upward from its original substantially horizontal position. As the ramped portion  48  and ramped surface  62  slide further along each other, the deflectable latch beam  36  is further deflected. As the plug housing  12  and header  18  are urged further still together, the flat portion  49  of the deflectable latch beam  36  begins to slide along the flat portion  64  of the latch mating element  60 . 
     Eventually, the trailing edge of the flat portion  49  of the deflectable latch beam  36  slides off the flat portion  64  of the latch mating element  60 . At this point, there is no longer a normal force deflecting the deflectable latch beam  36 . Consequently, the deflectable latch beam  36  snaps back to its original substantially horizontal position. With the deflectable latch beam  36  once again substantially horizontal, the latching portion  50  of the deflectable latch beam  36  and the vertical portion  66  of the latch mating element  60  cooperate to provide a positive mechanical stop preventing the separation of the now mated plug housing  12  and header  18 . Thus secured, the plug housing  12  and header  18  may only be separated by accidental or coincidental manual deflection of the deflectable latch beam  36  (such as by an operator&#39;s thumb pressing down on the deflectable latch beam  36  near the rear end  16  of the plug housing) and urging apart of the plug housing  12  and header  18 . 
     The header  18  also comprises a header rail  68  extending lengthwise along the top of the header  18 , offset from the center of the header  18 . The header rail  68  is configured for slidable contact with the rail surface  88  of the CPA  82 . Viewed from the front end  20  of the header  18 , the header rail  68  appears similar to an upside-down “L”. The header rail  68  includes an interior surface  70  and a stop  72 . 
     The header  18  also comprises a header bump  74  located proximate the center of the top of the front end  20  of the header  18 . The header bump  74  of the illustrated embodiment comprises a front ramped portion  76 , a flat portion  78 , and a rear ramped portion  80 . The header bump  74  cooperates with the finger  96  of the CPA  82  to help maintain the CPA in position, and also serves to deflect the finger  96  to free the finger  96  from the finger stop  42 . 
     FIGS. 12 and 13 illustrate isometric views of the connector position assurance device (CPA)  82 . The CPA comprises a front portion  84  and a rear portion  86 , as well as a top portion  83 . FIG. 14 illustrates a front view of the CPA  82  and FIG. 15 illustrates a sectional view of the CPA  82 . The top portion  83  of the CPA  82  includes rail sections  81  projecting along either side thereof. The rail section  81  include inner grooved rail surfaces  88  aligned to face one another and to extend along a length of the rail sections  81 . The rail sections  81  include open front and rear ends proximate the front and rear portions  84  and  86 . By way of example only, the rail section  81  and rail surfaces  88  may be formed in a C-shape. The rail surface  88  is configured for slidable contact with the latch rail  40  and header rail  68 . A bottom leg  90  is included in each “C” shape and comprises an interior surface  92  and a face  94  proximate the front portion  84 . Preferably, the CPA  82  also includes a stopping portion  95  mounted to and projecting down from the top portion  83 . The stopping portion  95  is configured to engage stopping portion  41  of deflectable latch beam  36  to prevent the CPA  82  from sliding out of the rear end  16  of the plug housing  12  once inserted to an initial, prestage position. 
     The CPA  82  further comprises a finger  96  located between the rail sections  88  and projecting downward from the bottom surface of the top portion  83 . The finger  96  comprises a base  98  mounted to the bottom surface of the top portion  83  and a cantilever beam  100  extending toward the front portion  84 . Finger  96  is normally biased in a substantially horizontal position. An embossment  102  is located near the end of the cantilever beam  100  and on its underside. The embossment  102  includes a flat portion  104 , a front ramped portion  106 , and a rear ramped portion  108 . The flat portion  104  is substantially as wide as the cantilever beam  100 , whereas the front ramped portion  106  and rear ramped portion  108  are narrower than the cantilever beam  100 . Both the front ramped portion  106  and rear ramped portion  108  slope from the base of the cantilever beam  100  to the edge of the flat portion  104 . The finger  96  cooperates with the finger stop  42  to maintain the CPA  82  in its retracted position  110  when the plug housing  12  and header  18  are not mated. Once the plug housing  12  and header  18  are mated and the CPA  82  has been advanced to its locked position  112 , the finger  96  cooperates with the header bump  74  to help maintain the CPA  82  in its locked position  112 . 
     FIGS. 16 and 18 illustrate sectional views of the sealed electrical connector assembly  10  with the CPA  82  in the retracted position  110 . FIGS. 17 and 19 illustrate sectional views of the sealed electrical connector assembly  10  with the CPA  82  in the locked position  112 . As described above, the plug housing  12  and header  18  once mated may only be separated by a coincident manual deflection of the deflectable latch beam  36  and urging apart of the plug housing  12  and header  18 . The CPA  82  in the locked position  112  restrains the deflectable latch beam  36  from deflecting, thereby preventing separation of the mated plug housing  12  and header  18 . When the CPA  82  is in the retracted position  110 , the deflectable latch beam  36  may be deflected vertically until the latch engaging surface  38  disengages the vertical portion  66  of the latch mating element  60 . Thereafter the plug housing  12  and header  18  may be separated. 
     When the CPA  82  is in the locked position  112  (FIGS.  17  and  19 ), the rail surface  88  is slidably engaged with the header rail  68 . Any attempted articulation upward by the front portion  37  of the deflectable latch beam  36  is met and prevented by the top portion  83  of the CPA  82 . Thus, for the deflectable latch beam  36  to deflect and allow separation of the plug housing  12  and header  18 , the CPA  82  must be free to move upward. However, the CPA  82  may not move upward when in the locked position  112 , as any such attempted movement is prevented by the interior surface  70  of the header rail  68  constraining the interior surface  92  of the bottom leg  90  of the rail surface  88  of the CPA  82 . When the CPA  82  is moved relatively from the front end  14  of the plug housing  12  to the rear end  16  and into its retracted position  110 , the CPA  82  slides free of the header rail  68 , and the interior surface  70  no longer constrains the upward movement of the CPA  82 . Thus, the deflectable latch beam  36  may be deflected and the plug housing  12  and header  18  separated from each other with the CPA  82  in the retracted position  110 . 
     For proper mating, the CPA  82  is preferably maintained in its retracted position  110  as the plug housing  12  and header  18  are urged toward each other. In the illustrated embodiment, the deflectable latch beam  36  comprises a finger stop  42  to help keep the CPA  82  in its retracted position  110  when the plug housing  12  and header  18  are not mated. The finger stop  42  comprises a channel  44  with ears  46 . The ears  46  define a gap  47 . Further, the finger  96  comprises an embossment  102  with a flat portion  104 . With the finger  96  in its normal substantially horizontal position, the flat portion  104  of the embossment  102  resides at least partially at the same elevation as the channel  44  and ears  46 . The width of the flat portion  104  exceeds the width of the gap  47 . The resulting interference between the flat portion  104  and ears  46  prevents any forward movement of the CPA  82 , maintaining it in the retracted position  110 . For the CPA  82  to move forward to the locked position  112 , the finger  96  must be deflected such that the flat portion  104  is no longer at the same elevation as the ears  46 . 
     If the CPA  82  starts in the retracted position  110 , the plug housing  12  and header  18  may be mated as described above. After mating, the deflectable latch beam  36  is once again substantially horizontal. Also, the header rail  68  and latch rail  40  are aligned such that the CPA  82  may slidably engage both simultaneously. As shown in FIG. 18, the header bump  74  and the embossment  102  of the finger  96  are configured such that there would be an interference  114  between the header bump  74  and the embossment  102  when the finger  96  is not deflected. However, the CPA  82  has not approached the header bump  74  solely from the horizontal. Rather, the CPA  82  was on the front portion  37  of the deflectable latch beam  36 . Consequently, the CPA  82  articulated with the front portion  37  as the latch engaging surface  38  traversed the latch mating element  60  as described above. The embossment  102  remains clear of the header bump  74  until the deflectable latch beam  36  snaps into place and returns to horizontal. As the deflectable latch beam  36  begins to snap into place with the CPA  82  in place on the latch rail  40 , the embossment “lands” on the header bump  74 . As the deflectable latch beam  36  completes its return to a substantially horizontal position, the finger  96  is deflected in a relatively upward direction with respect to the deflectable latch beam  36  by the interference  114  with the embossment  74 . 
     With the finger  96  thus deflected, the flat portion  104  is now at a different elevation than the ears  46 , and the CPA  82  may be advanced from the retracted position  110  to its locked position  112 . Because the latch rail  40  and the header rail  68  are aligned, the rail surface  88  of the CPA  82  is able to slidably engage the header rail  68  while maintaining slidable engagement with the latch rail  40  as the CPA advances toward the locked position  112 . Thus, with the rails aligned and the flat portion  104  clear of the ears  46 , the CPA  82  may be moved into the locked position  112 . As the CPA  82  advances, the embossment  102  will eventually clear the header bump  74 . As shown in FIG. 19, the finger  96  will then return to a substantially horizontal position, and the embossment  102  will cooperate with the header bump  74  to help maintain the CPA  82  in the locked position  112 . Preferably, the stop  72  of the header rail  68  cooperates with the face  94  of the rail surface  88  to prevent the CPA  82  from advancing too far forward. 
     The CPA  82  can be removed from the locked position  112  by an external force (such as that provided by an operator&#39;s thumb) urging the CPA  82  toward the rear end  16  of the plug housing  12 . As the CPA  82  moves toward the rear end  16 , the embossment  102  will encounter the rear ramped portion  80  of the header bump  74 . This contact will deflect the front of the finger  96  upward. When the CPA  82  is back in the retracted position  110 , the finger  96  will remain deflected, with the embossment  102  resting on the header bump  74 . As the plug housing  12  and header  18  are separated, the finger will return to a substantially horizontal position, and the flat portion  104  will once again be constrained by the ears  46  from moving to the locked position  112  while the plug housing  12  and header  18  are not mated. 
     Unfortunately, an unintended external force may deflect the finger  96  and move the CPA  82  into the locked position  112  when the plug housing  12  and header  18  are not mated. This can result in an improper mating when the plug housing  12  and header  18  are urged together, with the plug housing  12  and header  18  subject to the risk of unintended separation. Additionally, the operator may be forced to expend time returning the CPA  82  to the retracted position  110 . These problems may be avoided by a sealed electrical connector assembly that automatically returns the CPA to the retracted position upon the urging of the plug housing  12  and header  18  together. 
     As described more fully above, the front portion  37  of the deflectable latch arm  36  is deflected upward as the plug housing  12  and header  18  are urged together. When the CPA  82  is in the locked position  112 , it resides toward the front portion  37  of the deflectable latch beam  36 . From before, the latch rail  40  and header rail  68  are aligned when the deflectable latch arm  36  is substantially horizontal. However, they are not aligned when the deflectable latch arm  36  is deflected with its front portion  37  upward. 
     In the illustrated embodiment, the rail surface  88 , latch engaging surface  38 , and ramped surface  62  are configured such that the face  94  of the rail surface  88  contacts the header rail  68  when the CPA  82  is in the locked position  112  and the deflectable latch beam  36  is deflected upward as the plug housing  12  and header are urged toward each other. This interference urges the CPA  82  back toward the rear end  16  of the plug housing  12  as the plug housing  12  and header  18  are further urged toward each other. As the CPA  82  is thus urged backward, the embossment  102  encounters resistance that results in the finger  96  being deflected upward. The CPA  82  is then free to return to the retracted position  110 , and is forced into the retracted position  110  upon further urging of the plug housing  12  and header  18  together. Thus, the CPA  82  is automatically returned to the retracted position  110  during the mating of the plug housing  12  and the header  18 , thereby assuring proper mating as well as saving the operator time. Once the mating is complete, the CPA  82  may be advanced to the locked position  112  to assure that the plug housing  12  and header  18  remain mated. 
     While particular elements, embodiments and applications of the present invention have been shown and described, it will be understood, of course, that the invention is not limited thereto since modifications may be made by those skilled in the art, particularly in light of the foregoing teachings. It is therefore contemplated by the appended claims to cover such modifications as incorporate those features which come within the spirit and scope of the invention.