Abstract:
An electrical connector assembly is provided, including a connector position assurance device (CPA) movable between locked and unlocked positions along a longitudinal axis of the CPA. The CPA includes rails. The connector assembly also includes first and second connector housings having mating ends configured to mate with one another. A CPA guide assembly is mounted to at least one of the first and second connector housings. The CPA guide assembly includes CPA guide rails slidably accepting the guide rail of the CPA. The CPA permits engagement and disengagement of the first and second connector housings when in the unlocked position. The CPA prevents disengagement of the first and second connector housings when in the locked position. When the first and second connector housings are disengaged, the CPA can not move to the locked position. The connector assembly further includes a sweeping element mounted to the CPA. The sweeping element is configured to extend laterally from the longitudinal axis of the CPA and positioned to provide a wedge to remove debris from the housing of the connector as the CPA is moved to the unlocked position. The debris builds up on the connector assembly while engaged and the CPA is locked. The removal of the debris occurs during movement of the CPA to the unlocked position because it is then that a connector latch should deflect to release the mating connector.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    Certain embodiments of the present invention generally relate to an electrical connector assembly that includes a self-cleaning connector position assurance device (CPA) that ensures matable connectable halves are fully mated with another.  
           [0002]    Connector devices have been proposed that provide electrical terminals having matable male to female connector halves. One of the male and female connector halves may include a resilient latch that locks behind a feature on the complementary connector half. When the connector halves are mated, a CPA is inserted to a locked position indicating that the connector halves are fully mated. The CPA is movable between a locked position indicating that the connector halves are mated and an unlocked position permitting unmating of the connector halves. An example of a connector assembly including a CPA may be found in U.S. Pat. No. 5,643,003. Some applications, however, require sealing to protect components from contamination from external sources. An example of a sealed connector assembly with a CPA can be found at U.S. Patent Application Publication No. US 2002/0115332A1 entitled “Connector Position Assurance Device For A Sealed Connector,” published Aug. 22, 2002.  
           [0003]    Some electrical connector applications involve use in high-debris environments, such as in construction equipment that is exposed to mud and dirt. In these applications, debris may accumulate on the connector when in the locked position. The debris may prevent the connector halves from being unmated. More specifically, debris, such as mud, may accumulate around the resilient latch securing the connector halves together. As the CPA is moved to the unlocked position, the debris becomes packed under the resilient latch which prevents the resilient latch from being deflected to a position at which it would otherwise release a latch feature on the mated connector half. If the latch cannot be deflected, the connector halves cannot be unmated. An operator in the field must then remove the debris from the connector, a process that consumes valuable time and may result in damage to the CPA, latch, or other connector components. A secondary problem with conventional connectors is that the debris renders it more difficult to move the CPA.  
           [0004]    A need exists for an improved CPA connector assembly to overcome the above-noted and other disadvantages of conventional connectors.  
         BRIEF SUMMARY OF THE INVENTION  
         [0005]    An electrical connector assembly is provided, including a connector position assurance device (CPA) movable between locked and unlocked positions along a longitudinal axis of the CPA. The CPA includes rails. The connector assembly also includes first and second connector housings having mating ends configured to mate with one another. A CPA guide assembly is mounted to at least one of the first and second connector housings. The CPA guide assembly includes CPA guide rails slidably accepting the guide rail of the CPA. The CPA permits engagement and disengagement of the first and second connector housings when in the unlocked position. When the first and second connector housings are disengaged, the CPA can not move to the locked position. The connector assembly further includes a sweeping element mounted to the CPA. The sweeping element is configured to extend laterally from the longitudinal axis of the CPA and positioned to provide a wedge to remove debris from the housing of the connector as the CPA is moved to the unlocked position.  
           [0006]    In at least one embodiment, the connector assembly is formed with a resiliently deflectable latch assembly mounted to, and being positioned above, one of the first and second connector housings. The latch assembly is spaced from the corresponding first and second connector housing to define a gap therebetween. The sweeping element of the CPA is positioned to remove debris from the gap and to block entry of additional debris when the CPA is in the locked position.  
           [0007]    In accordance with at least one embodiment, multiple sweeping elements may be formed on the CPA with sloped surfaces extending laterally from either side of the CPA. The sloped surfaces may be formed at an acute or an obtuse angle with respect to one another. The CPA may also be provided with a blocking portion aligned to prevent debris from collecting under a latch assembly mounted to one of the first and second connector housings.  
           [0008]    Certain embodiments of the present invention thus provide an electrical connector system that performs better in high-debris applications by removing debris and/or preventing accumulation of debris. 
       
    
    
     BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 illustrates an isometric view of a connector system with a CPA in a locked position, formed in accordance with an embodiment of the present invention.  
         [0010]    [0010]FIG. 2 illustrates an isometric view of a connector system with a CPA in an unlocked position, formed in accordance with an embodiment of the present invention.  
         [0011]    [0011]FIG. 3 illustrates a side section taken along line  3 - 3  in FIG. 1 of the connector system with the CPA in the locked position.  
         [0012]    [0012]FIG. 4 illustrates a partial isometric view of a portion of the connector system and CPA in the locked position of FIG. 1.  
         [0013]    [0013]FIG. 5 illustrates a partial isometric view of a portion of the connector system and CPA in the unlocked position of FIG. 2.  
         [0014]    [0014]FIG. 6 illustrates a bottom isometric view of a CPA with sweeping and blocking elements formed thereon in accordance with an embodiment of the present invention. 
     
    
       [0015]    The foregoing summary, as well as the following detailed description of certain 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, certain embodiments. It should be understood, however, that the present invention is not limited to the arrangements and instrumentality shown in the attached drawings.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0016]    [0016]FIGS. 1 and 2 illustrate isometric views of a connector system  10 . The connector system  10  includes a plug connector housing  12  that is mated to a cap connector housing  14 . The connector system  10  also includes a connector position assurance device (CPA)  16  movable between locked and unlocked positions. In the locked position, as illustrated in FIG. 1, the CPA  16  indicates that the plug connector housing  12  and cap connector housing  14  are fully mated and prevents the separation of the mated plug and cap connector housings  12  and  14 . In the unlocked position, illustrated in FIG. 2, the CPA  16  permits the separation of the plug and cap connector housings  12  and  14 .  
         [0017]    [0017]FIG. 3 illustrates a side sectional view taken along line  3 - 3  of FIG. 1, with the plug connector housing  12  and cap connector housing  14  mated, and the CPA  16  in the locked position. With reference to FIGS.  1 - 2 , the plug connector housing  12  includes sides  20  joining a top portion  22  and a bottom portion  24 . Also, the plug connector housing  12  includes a mating end  26  and a back end  28  (FIG. 3). The mating end  26  includes a plug contact array (not shown) that contacts and electrically communicates with a corresponding cap contact array (not shown). Proximal to the back end  28 , the plug connector housing  12  includes a wire seal  32 , through which a wire harness (not shown) passes. The illustrated embodiment is an 8 position connector having contacts arranged in two rows of four contacts each. The wire harness is in electrical communication with the plug contact array. The plug connector housing  12  also includes a plug cap  30  that is placed over the back end  28  to maintain the wire seal  32  in position and to help prevent debris from entering the interior of the plug connector housing  12 .  
         [0018]    The top portion  22  of the plug connector housing  12  includes a latch assembly  34 . The latch assembly includes a resilient latch arm  36 . The latch assembly  34  is resiliently deflectable in direction A, pivoting about a point located intermediately along its length, to permit engagement and disengagement of the plug connector housing  12  and cap connector housing  14 . Proximal to the mating end  26  of the plug connector housing  12 , the latch assembly  34  terminates at a retention feature  38 . The retention feature  38  includes a retention surface  40  extending away from the bottom of the latch arm  36 . The retention surface  40  cooperates with the cap connector housing  14  to maintain the plug connector housing  12  and cap connector housing  14  in a mated position after the plug connector housing  12  and cap connector housing  14  are mated. Extending substantially horizontally from an edge of the retention surface  40  is a bottom surface  42 . The bottom surface  42  joins the retention surface  40  to a front surface  44  that is substantially parallel to the retention surface  40 . The front surface  44  cooperates with the cap connector housing  14  to prevent the entry of debris proximal to the mating end  26  to the area around the latch assembly  34 .  
         [0019]    Opposite to the retention feature  38  along the length of the latch arm  36 , the latch assembly  34  includes a finger bump  46 . The finger bump  46  includes a top  48  and a bottom  50 . The top  48  includes a sloped surface  49  leading from the latch arm  36  toward the back of the latch assembly  34 . An operator can push in the downward direction of FIG. 3 on the top  48  of the finger bump  46  to release the latch assembly  34 , as pushing downward on the finger bump  46  biases the latch assembly  34  in direction A, causing the retention feature  38  to move upward. However, when the CPA  16  is in the locked position, as shown in FIG. 3, the bottom  50  of the finger bump  46  contacts the CPA  16  which prevents the biasing along direction A, thereby preventing the release of the latch assembly  34  and maintaining the plug connector housing  12  and cap connector housing  14  in a fully mated position.  
         [0020]    The plug connector housing  12  further includes a seal  52  surrounding an outside surface defined along an exterior surface along the sides  20 , top  22 , and bottom  24  of the plug connector housing  12  located proximal to the mating end  26 . The seal cooperates with the plug connector housing  12  and cap connector housing  14  to prevent debris from entering the interior of the plug connector housing  12  and cap connector housing  14  when they are mated.  
         [0021]    Turning to FIG. 4, proximal to the back end  28  of the plug connector housing  12 , the top portion  22  of the plug connector housing  12  and/or the plug cap  30  include a CPA holder  54 . The CPA holder  54  functions to retain the CPA  16  when the CPA  16  is in the unlocked position and/or the plug connector housing  12  and cap connector housing  14  are separated. The CPA holder  54  includes two CPA holder rails  56  extending from the top portion  22 , facing one another and configured to slidably accept the CPA  16 . The CPA holder rails  56  include CPA holder rail top ledges  58 , which prevent the CPA  16  from moving upward away from the top portion  22  of the plug connector housing  12 . The CPA holder  54  also includes a CPA retention feature  60  that is configured to prevent the CPA  16  from entirely sliding off the back end  28  of the plug connector housing  12 .  
         [0022]    As shown in FIGS.  1 - 3 , the cap connector housing  14  includes a front end  72  and a back end  74 . Proximal to the front end  72 , the cap connector housing  14  also includes an opening  70  (FIG. 3) configured to accept the mating end  26  of the plug connector housing  12 . Further, the cap connector housing  14  includes a top portion  80  and a bottom portion  82  joined by sides  84 . The front end  72  includes a cap contact array (not shown) that contacts and electrically communicates with the corresponding plug contact array (not shown). Proximal to the back end  74  of the cap connector housing  14 , the cap connector housing  14  includes a wire seal  78 , through which a wire harness (not shown) passes. The wire harness is in electrical communication with the cap contact array. The cap connector housing  14  also includes a back cap  76  that is placed over the back end  74  to maintain the wire seal  78  in position and to help prevent debris from entering the interior of the cap connector housing  14 .  
         [0023]    As shown in FIG. 3, the cap connector housing  14  includes a latch bump  86  extending from the top portion  80  of the cap connector housing  14 . The latch bump  86  cooperates with the latch assembly  34  to maintain the plug connector housing  12  and cap connector housing  14  in a mated position. The latch bump  86  includes a sloped surface  88  extending generally upward from the top portion  80  and towards the back end  74 . The sloped surface  88  terminates at a substantially horizontal top surface  90 . The top surface  90  joins a latch retention surface  92  that is substantially vertical and extends back toward the top portion  80  from the edge of the top surface  90 .  
         [0024]    With reference to FIG. 5, the cap connector housing  14  also includes a CPA guide  94  extending from the top portion  80 . The CPA guide  94  includes two CPA guide rails  96 . The CPA guide rails  96  are generally C-shaped and are sized and configured to slidably accept the CPA  16 . At ends nearest the back end  74  of the cap connector housing  14 , the CPA guide rails  96  are joined by a back surface  98 . The back surface  98  is substantially vertical and cooperates with the latch assembly  34  and/or the latch bump  86  to prevent debris from entering the area beneath the latch assembly  34  from the direction from the back end  74  of the cap connector housing  14 . The CPA  16  is moved along direction B between the locked and unlocked positions. In FIG. 4, the CPA  16  is in the locked position, and in FIG. 5 the CPA  16  is in the unlocked position.  
         [0025]    [0025]FIG. 6 illustrates a bottom isometric view of the CPA  16 . The CPA  16  includes a front portion  100  and a back portion  102  joined by sides  104 . The front portion  100 , back portion  102 , and sides  104  define an open channel  105  through which the latch assembly  34  may be biased when the CPA  16  is in the unlocked position (FIG. 5). The front portion  100  of the CPA  16  includes a top surface  110  (FIG. 5) and a bottom surface  112  (FIG. 6). The front portion  100  includes a thumb rest  106  extending above the top surface  110 . The thumb rest  106  may be used by an operator to move the CPA  16  along direction B between the locked and unlocked positions. The CPA  16  includes a cross member  108  (FIG. 3) extending beneath the bottom surface  112  and parallel to sides  104 . The cross member  108  and/or the bottom surface  112  may provide assistance in deflecting the latch assembly  34  when the CPA  16  is moved to the unlocked position. The cross member  108  may also be used to prevent the upward movement of the latch arm  36  when the CPA  16  is in the locked position.  
         [0026]    With reference again to FIGS.  4 - 5 , each side  104  of the CPA  16  includes a rail  116  extending therefrom. The rails  116  are configured to be slidably accepted by the CPA guide rails  96  of the cap connector housing  14 .  
         [0027]    The back portion  102  of the CPA  16  includes a blocking portion  124  with first and second sweeping elements  134  and  135  joined thereto. The blocking portion  124  includes a top surface  126  and a bottom surface  128  joined by sides  130 . The blocking portion also includes a back end  132 . The blocking portion  124  is positioned underneath the finger bump  46  of the latch assembly  34 , preventing downward movement of the finger bump  46  and blocking the entry of debris underneath the latch assembly  34  from the back end  28  of the plug connector housing  12  when the CPA  16  is in the locked position (FIG. 4).  
         [0028]    The sweeping element  134  extends from the sides  130  of the blocking portion  124 . The sweeping element  134  includes sloped surfaces  136  extending outward from the sides  130  to form an acute angle with a longitudinal axis of the CPA  16 . The sweeping element  135  extends below the sweeping element  134  and is oriented perpendicular to the direction B along which the CPA  16  is moved between locked and unlocked positions. The sweeping element  135  includes sloped surfaces  137  joining at an obtuse angle. The sweeping elements  134  and  135  provide wedges or plows to help move the back portion  102  through any accumulated and/or caked in mud or other debris that may be behind the back portion  102  of the CPA  16  when the CPA  16  is moved from the locked position to the unlocked position. The sweeping elements  134  and  135  may also cooperate to block entry of debris underneath the latch assembly  34 . Optionally, the sweeping elements  134  and  135  may converge to one or more lead edges similar to the lead edge  139  formed at the intersection of sloped surfaces  137 .  
         [0029]    The mating (engagement) and unmating (disengagement) processes for the connector system  10  will now be described. First, the plug connector housing  12  and cap connector housing  14  are positioned such that the mating end  26  of the plug connector housing  12  faces toward the front end  72  of the cap connector housing  14  and the top portions  22 ,  80  of the plug connector housing  12  and cap connector housing  14 , respectively, are aligned. The CPA  16  is in the unlocked position and held by the CPA holder  54  of the plug connector housing  12 . Aligned as described, the plug connector housing  12  and cap connector housing  14  are then urged toward each other. The mating end  26  of the plug connector housing  12  is accepted in the opening  70  of the cap connector housing  14 , and the rails  116  of the CPA  16  (with the CPA  16  still in the unlocked position) are accepted by the CPA guide rails  96  of the cap connector housing  14 .  
         [0030]    As the mating end  26  enters the opening  70 , the latch assembly  34  is resiliently biased. The front surface  44  of the latch assembly  34  encounters the sloped surface  88  of the latch bump  86  of the cap connector housing  14 . As the front surface  44  rides along the sloped surface  88 , the latch assembly  34  is biased along direction A. Eventually, the front surface  44  passes the sloped surface  88 , and the bottom surface  42  of the latch assembly  34  rides along the top surface  90  of the latch bump  86 . Further entry of the plug connector housing  12  into the cap connector housing  14  results in the bottom surface  42  passing the top surface  90 . The latch assembly  34  then snaps back to its original unbiased position, with the retention surface  40  of the latch assembly  34  now abutting the latch retention surface  92  of the latch bump  86 . At this point, the respective contact assemblies of the plug connector housing  12  and cap connector housing  14  are in the desired final position providing electrical communication, and the connector system  10  is fully mated. With the latch assembly  34  positioned as such, the retention surface  40  and the latch retention surface  92  cooperate to maintain the plug connector housing  12  and cap connector housing  14  together. Further, the front surface  44  of the latch assembly  34  cooperates with the back surface  98  of the cap connector housing  14  to help prevent debris from accumulating near the latch assembly  34 . To separate the plug connector housing  12  and cap connector housing  14 , the latch assembly  34  must be deflected such that the retention surface  40  is clear of the latch retention surface  92 .  
         [0031]    The CPA  16  may be moved to the locked position to prevent deflection of the latch assembly  34  and engagement or disengagement of the plug connector housing  12  and cap connector housing  14 . With the plug connector housing  12  and cap connector housing  14  fully mated, the CPA  16  may be advanced from the unlocked position to the locked position. In the locked position, the blocking portion  124  of the CPA  16  resides beneath the finger bump  46  of the latch assembly  34 , preventing downward deflection of the finger bump  46 . Thus, the latch assembly  34  is prevented from biasing when the CPA  16  is in the locked position, thereby keeping the plug connector housing  12  and cap connector housing  14  from being separated. The blocking portion  124  also substantially blocks the portion of the volume  51  beneath the finger bump  46 , thereby substantially closing off the volume  51 . Thus, the CPA  16  prevents the entry and accumulation of debris under the latch assembly  34  that could inhibit retraction of the CPA  16  to the unlocked position and/or deflection of the latch assembly  34  when it is desired to separate the plug connector housing  12  and the cap connector housing  14 .  
         [0032]    To unmate the plug connector housing  12  and cap connector housing  14 , the CPA  16  is moved to the unlocked position (FIGS. 2 and 5). If debris has accumulated behind the CPA  16 , blocking its movement, the sweeping element  134  provides a plow to facilitate movement through and removal of the debris. Additionally, the cross member  108  may also assist in the removal of and movement through any debris that may have accumulated beneath the bottom surface  112  of the front portion  100  of the CPA  16 . Because the CPA  16  helps prevent accumulation of debris in the volume  51  and also acts to remove debris during the course of its movement to the unlocked position, once the CPA  16  is in the unlocked position, the latch assembly  34  may be deflected without interference from debris, allowing separation of the plug connector housing  12  and cap connector housing  14 . Additionally, the cross member  108  of the CPA  16  may ride along the sloped surface  49  of the finger bump  46  to assist in the deflection of the latch assembly  34  during unmating. As a further option, a sweeping element may be added proximal to the thumb rest  106  to assist in the movement of the CPA  16  should debris accumulate near the thumb rest  106 .  
         [0033]    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.