Abstract:
An electrical connector assembly is provided including first and second housings having ends configured to receive electrical contacts. The first and second housings are configured to be matable with one another to join corresponding electrical contacts. The electrical connector assembly includes a lever member having a cam arm received by the first housing and engaging the second housing as the lever member is rotated through a range of motion from an insertion position to an engaged position. The lever member connects the first and second housings to join corresponding electrical contacts when the lever member is rotated to the engaged position. The lever member has a position assurance tab received by the first housing.

Description:
BACKGROUND OF THE INVENTION 
   Certain embodiments of the present invention relate to connection assurance features on an electrical connector assembly. More particularly, certain embodiments of the present invention relate to connection assurance features that engage a lever and a first housing when the lever is rotated to connect first and second housings. 
   In certain applications, electronic components require an electrical connector assembly that joins first and second housings containing electrical contacts. One housing includes male electrical contacts, while the other housing includes female electrical contacts. The first housing is configured to receive the second housing such that the male and female electrical contacts are electrically connected. 
   In the typical electrical connector assembly, the first housing is connected to the second housing by hand. In order to be sure that the first and second housings are properly connected with the electrical contacts electrically engaged, the first and second housings are provided with a latch assembly more generally referred to a as a positioning assurance feature. The latch assembly includes a base plate slidably retained on the first housing beneath a suspended prong and a ramp on the second housing. When the first housing is inserted about the second housing, the prong slides over the ramp and the base plate is then slid over the ramp and the prong into a final position. When the base plate is in the final position, an operator is assured that the first and second housings are fully connected. 
   However, as the number of electrical contacts to be mated increases, it becomes difficult to fully join the first and second housings because of friction between the mating electrical contacts. Therefore, many electrical connector assemblies include a mate assist assembly that overcomes the frictional resistance involved in mating the first and second housings. The typical mate assist assembly is a lever member connected to one of the housings which has cam arms that engage racks on the other housing as the lever member is rotated through a range of motion. The interaction of the cam arms and the racks provides force to overcome the friction between the electrical contacts and easily connect the first and second housings. 
   The typical mate assist assembly suffers from a number of drawbacks. A latch assembly connected to the first and second housings can interfere with the lever member of a mate assist assembly. In operation the lever member may appear to be fully rotated to a final position and indicate to an operator that the first and second housings are fully connected when in fact the lever member is not fully rotated to the final position or did not properly engage the racks to connect the first and second housings. The first housing may only loosely be retained about the second housing such that the electrical contacts are not connected or are in danger of becoming unconnected. 
   Therefore, a need exists for a connector assembly that overcomes the above problems and addresses other concerns experienced in the prior art. 
   BRIEF SUMMARY OF THE INVENTION 
   Certain embodiments provide an electrical connector assembly including first and second housings having ends configured to receive electrical contacts. The first and second housings are configured to be matable with one another to join corresponding electrical contacts. The electrical connector assembly includes a lever member having a cam arm received by the first housing and engaging the second housing as the lever member is rotated through a range of motion from an insertion position to an engaged position. The lever member connects the first and second housings to join corresponding electrical contacts when the lever member is rotated to the engaged position. The lever member has a position assurance tab received by the first housing. 

   
     BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS 
       FIG. 1  illustrates an isometric view of an electrical connector assembly formed according to an embodiment of the present invention. 
       FIG. 2  illustrates an isometric view of the lever member according to an embodiment of the present invention. 
       FIG. 3  illustrates the electrical connector assembly in the initial staging position according to an embodiment of the present invention. 
       FIG. 4  illustrates an isometric view of the electrical connector assembly in the final position according to an embodiment of the present invention. 
       FIG. 5  illustrates an isometric view of an electrical connector assembly formed according to an embodiment of the present invention. 
   

   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 
     FIG. 1  illustrates an isometric view of an electrical connector assembly  10  formed according to an embodiment of the present invention. The electrical connector assembly  10  includes a harness connector  14  connected to a lever member  18  and positioned to receive a header connector  22 . The harness connector  14  and header connector  22  carry groups of electrical contacts (not shown). When the harness connector  14  is mounted onto the header connector  22  in an initial staging position (FIG.  3 ), the lever member  18  is rotated in the direction of arrow A about a rotational axis  86  to move the harness connector  14  from the initial staging position to a final position ( FIG. 4 ) where the harness connector  14  is received by the header connector  22  and the electrical contacts are connected with each other. 
   The harness connector  14  includes opposite top and bottom walls  26  and  30  formed with opposite side walls  34 . A radial top surface  38  with a catch  42  extends from one of the side walls  34 . The lever member  18  is shown in an insertion position about the harness connector  14  and is received in apertures  54  in the side walls  34 . 
     FIG. 2  illustrates an isometric view of the lever member  18  according to an embodiment of the present invention. The lever member  18  includes lever arms  46  having cam arms  50  that are rotatably received within the side walls  34  ( FIG. 1 ) of the harness connector  14  (FIG.  1 ). The cam arms  50  have gear teeth  74  separated by a rack gap  68 . The cam arms  50  engage racks  70  ( FIG. 1 ) on the header connector  22  ( FIG. 1 ) as the lever member  18  is rotated to connect the header and harness connectors  22  and  14 . A long rectangular slot  90  extends through a lever arm  46  to receive a position assurance tab  94  (FIG.  1 ). 
   Returning to  FIG. 1 , the header connector  22  has opposite top and bottom walls  58  and  62  formed with opposite side walls  66 . The racks  70  extend outward from the side walls  66  and each rack  70  has a rack tooth  78  and a tooth gap  82 . In operation, when the harness connector  14  is placed on the header connector  22  in the initial staging position and the lever member  18  is rotated in the direction of arrow A about the rotational axis  86 , the cam arms  50  engage the racks  70  such that the gear teeth  74  rotate about the rack teeth  78  with the gear teeth  74  entering the tooth gaps  82  and the rack teeth  78  entering the rack gaps  68  (FIG.  2 ). The interaction between the rack teeth  78  and the gear teeth  74  pulls the harness connector  14  about the header connector  22  and connects the electrical contacts. When the lever member  18  has been fully rotated in the direction of A to connect the harness and header connectors  14  and  22 , the harness and header connectors  14  and  22  are in the final position and the lever member  18  is in an engaged position. Alternatively, to disengage the harness and header connectors  14  and  22 , the lever member  18  is rotated about the rotational axis  86  in the direction of arrow C. 
   The lever arm  46  retains the rectangular positioning assurance tab (PAT)  94 . The PAT  94  has two push pads  98  on one side and a stop  102  on an opposite side. The stop  102  is L-shaped and has a rectangular base portion  106  and a rectangular extended portion  110 . When the lever member  18  is in the insertion position, the PAT  94  is inserted into the slot  90  such that the extended portion  110  extends through the lever arm  46  with a bottom surface  114  of the extended portion  110  resting upon the radial top surface  38  of the side wall  34  and a top surface  118  of the extended portion  110  engaging a top surface  122  of the slot  90 . The PAT  94  is thus retained in an upper position within the slot  90 . When the lever member  18  is in the engaged position, a bottom surface  126  of the base portion  106  engages a bottom surface  130  of the slot  90 . The PAT  94  is thus retained in a lower position within the slot  90 . 
     FIG. 3  illustrates the electrical connector assembly  10  in the initial staging position according to an embodiment of the present invention. When the harness connector  14  is moved onto the header connector  22  into the initial staging position, the lever member  18  is rotated in the direction of arrow A about the rotational axis  86  to connect the harness and header connectors  14  and  22 . As the lever member  18  rotates in the direction of arrow A, the PAT  94  remains in the upper position within the slot  90  with the extended portion  110  ( FIG. 1 ) of the stop  102  ( FIG. 1 ) sliding along the radial top surface  38 . When the lever member  18  is rotated to a point above the catch  42  in the radial top surface  38 , the PAT  94  slides linearly downward within the slot  90  in the direction of Arrow D relative to the lever arm  46  into the lower position with the extended portion  110  of the stop  102  retained in the catch  42 . 
     FIG. 4  illustrates an isometric view of the electrical connector assembly  10  in the final position according to an embodiment of the present invention. When the PAT  94  is in the lower position, as shown, the lever member  18  is locked in the engaged position with the harness and header connectors  14  and  22  fully connected. Thus, when the PAT  94  is in the lower position, it provides visual assurance to an operator that the harness and header connectors  14  and  22  are in the final position and the electrical contacts are connected. Alternatively, the lever member  18  may be released from the engaged position by moving the push pads  98  in the direction of arrow K with respect to the lever arm  46  to move the PAT  94  from the lower position to the upper position and thus remove the extended portion  110  ( FIG. 1 ) from the catch  42  (FIG.  1 ). When the extended portion  110  is out of the catch  42 , the lever member  18  may be rotated about the rotational axis  86  in the direction of arrow C to disengage the harness connector  14  from the header connector  22 . 
     FIG. 5  illustrates an isometric view of an electrical connector assembly  200  formed according to an embodiment of the present invention. The connector assembly  200  includes a lever member  204 , a harness connector  208 , and a header connector  212 . The lever member  204  is in the insertion position and has lever arms  216  that are rotatably retained within side walls  220  of the harness connector  208 . The lever arms  216  include cam arms  248  that engage racks  252  on the header connector  212  as described above. The harness connector  208  receives the header connector  212  and is fully connected to the header connector  212  when the lever member  204  is rotated in the direction of arrow A about a rotational axis  224  from the insertion position to the engaged position. 
   A lever arm  216  includes an aperture (not shown) receiving a knob-shaped PAT  232 . The PAT  232  includes a post  236  formed with a handle  240 , and the post  236  extends through the aperture. The side wall  220  of the harness connector  208  has a catch or post hole  244  situated therein. As the lever member  204  is rotated about the rotational axis  224  in the direction of arrow A from the insertion position to the final position, the handle  240  is pressed inward against the lever arm  216  such that the post  236  slides against the side wall  220  until the post  236  is positioned over the post hole  244 . The post  236  then slides into the post hole  244  and the handle  240  slides inward against the lever arm  216 . The PAT  232  is thus locked within the post hole  244  such that the lever member  204  is in the engaged position and may not be rotated about the rotational axis  224  in any direction. When the lever member  204  is in the engaged position, the harness and header connectors  208  and  212  are in the final position and the electrical contacts are fully connected. Therefore, the PAT  232  serves to lock the lever member  204  in the engaged position and provide visual assurance that the harness and header connector  208  and  212  are fully connected. 
   Alternatively, the lever member  204  may be released from the engaged position by moving the handle  240  outward away from the lever arm  216  such that the post  236  is withdrawn from the post hole  244 . When the post  236  is out of the post hole  244 , the lever member  204  may be rotated about the rotational axis  224  in the direction of arrow C to disengage the harness connector  208  from the header connector  212 . 
   The connector assembly of the various embodiments provides several benefits. First, the PATs provide visual assurance to an operator that the lever member is in an engaged position such that the harness connector and header connector are fully engaged in a final position and the electrical contacts are connected. Thus, the operator knows that the harness connector will not become disengaged from the header connector or that the electrical contacts will become disengaged. Secondly, the PATs lock the lever member in the engaged position, and the lever member may not be removed from the engaged position unless the PATs are manipulated to unlock the lever member. Thus, the lever members are not free to rotate and disengage the harness and header connectors and the electrical contacts. Also, the location of the PATs on the lever member takes up little space and does not interfere with the rotation of the lever member or the connection of the harness and header connectors. Further, the PATs are easy to manufacture and may be pre-assembled to the lever members before connecting the lever member to the harness connector such that the lever members may be shipped separately form the harness and header connectors. 
   While the invention has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.