Patent Publication Number: US-6655999-B2

Title: Connector and a method of assembling it

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a connector with a terminal fitting that is doubly locked by a retainer and to a method of assembling or mounting it. 
     2. Description of the Related Art 
     Japanese Unexamined Patent Publication No. 64-54678 discloses a connector that has a housing and a retainer that is movable in the housing from a partial locking position to a full locking position. Terminal fittings can be inserted into the housing when the retainer is at the partial locking position. The housing is formed with locks that engage the terminal fittings when the terminal fittings reach a properly inserted position. The retainer then is pushed to the full locking position and into engagement with the terminal fittings. Thus, the terminal fittings are locked doubly by the locks and the retainer. 
     The locks are cantilevered parallel with the inserting and withdrawing directions of the terminal fittings. However, free ends of the locks are displaced as the terminal fittings are inserted and describe a substantially arcuate trace. Thus, the locks come out of the insertion paths of the terminal fittings. The locks are restored resiliently when the terminal fittings reach their proper insertion positions, and the free ends of the locks engage the terminal fittings. Clearances necessarily are formed between the free ends of the locks and the terminal fittings when the terminal fittings are inserted properly. Further, the retainer locks the terminal fittings substantially at the same positions as the free ends of the locks. Thus, the terminal fittings may shake in the inserting and withdrawing directions due to the clearances between the free ends of the locks and the terminal fittings at their proper insertion positions. 
     This invention was developed in view of the above problem, and an object thereof is to suppress shaking of terminal fittings in inserting and withdrawing directions. 
     SUMMARY OF THE INVENTION 
     The invention relates to a connector with a housing and a retainer that can be moved from a partial locking position to a full locking position in the housing. At least one terminal fitting can be inserted into the housing when the retainer is in the partial locking position. The housing is formed with at least one lock that is displaced at an incline as the terminal fitting is inserted into the housing. The lock is restored resiliently when further movement in a terminal inserting direction is prevented. The resiliently restored lock engages the terminal fitting to lock the terminal fitting in the housing. The terminal fitting is locked, but is permitted to displace between the proper insertion position and a locking position that is spaced from the proper insertion position. The retainer then is moved to the full locking position and locks the terminal fitting by facing the terminal fitting from a terminal withdrawal side. The retainer comprises at least one pusher that engages the terminal fitting when the retainer is moved to the full locking position. The pusher contacts the terminal fitting from the terminal withdrawal side to hold the terminal fitting at its proper insertion position and to prevent the terminal fitting from shaking. 
     The retainer may be displaced in forward and backward directions with respect to the housing while the retainer is at the partial locking position. Alternatively, the retainer may be prevented from displacing or shaking in forward and backward directions with respect to the housing. In the latter case, the retainer is hardly moved forward and backward when being moved from the partial locking position to the full locking position. Thus, the retainer may be moved with the terminal fitting inserted to its proper insertion position. 
     The retainer and/or the housing may comprise displacing means for displacing the retainer at an angle, and preferably substantially forward, as the retainer is moved from the partial locking position to the full locking position. 
     At least one of the retainer and the terminal fitting may comprise a contact that obliquely contacts the other of the retainer and the terminal fitting as the retainer is moved from the partial locking position to the full locking position. 
     The lock permits the properly inserted terminal fitting to shake between the proper insertion position and the locking position. However, the retainer moves forward as it is advanced from the partial locking position to the full locking position and holds the terminal fitting at the proper insertion position. The contact of the retainer pushes the terminal fitting forward even if the terminal fitting is behind its proper insertion position when the retainer is moved to the full locking position. 
     The housing may comprise a receiving projection. The receiving projection has a partial locking receiving surface and a full locking receiving surface. The retainer preferably comprises a locking projection that has a partial locking surface and a full locking surface. Loose movement of the retainer from the partial locking position toward the full locking position is prevented by contact of the partial locking surface with the partial locking receiving surface. Loose movement of the retainer from the full locking position toward the partial locking position is prevented by contact of the full locking surface with the full locking receiving surface. 
     The retainer can be displaced forward as it is moved from the partial locking position to the full locking position. This displacement increases an engaged area of the receiving projection and the locking projection. An engaged area of the full locking receiving surface and the full locking surface is larger than an engaged area of the partial locking surface and the partial locking receiving surface. The increased engaged area holds the retainer at the full locking position more reliably and prevents inclination of the retainer. 
     The retainer preferably can make loose movements substantially along the terminal insertion direction with respect to the housing when arranged in the partial locking position whereas it substantially is prevented from making a loose movement when arranged in the full locking position. 
     Paired partial locking means preferably are provided at the opposite ends of the retainer with respect to a direction normal to a terminal inserting direction. The partial locking means of the retainer may engage receiving portions of the housing for preventing the retainer at the partial locking position from moving loosely toward the full locking position. 
     Spaced apart paired full locking means preferably are at the opposite ends of the retainer with respect to the direction normal to the terminal inserting direction. The pair of full locking means engage the receiving portions of the housing to prevent the retainer at the full locking position from moving loosely toward the partial locking position. 
     At least the partial locking means or the full locking means are provided at two positions spaced apart in a direction substantially parallel with the terminal inserting direction. 
     The invention also relates to a method for assembling or mounting a connector. The method comprises inserting at least one terminal fitting into a housing with a retainer mounted at a partial locking position in the housing. The terminal fitting is inserted until further movement in a terminal inserting direction is prevented. The terminal fitting is locked, but may displace between the proper insertion position and a locking position. The method then comprises moving the retainer at an angle to the terminal inserting direction from the partial locking position to a full locking position to lock the terminal fitting by facing the terminal fitting from a terminal withdrawal side. At least one pusher of the retainer is before a locking section of the lock and is engageable with the terminal fitting. The method comprises moving the retainer to the full locking position so that the pusher contacts the terminal fitting from the terminal withdrawal side for holding the terminal fitting at its proper insertion position and to prevent the terminal fitting from shaking. 
     The retainer preferably is permitted to displace at an angle to the retainer moving direction with respect to the housing while being held at the partial locking position. 
     The retainer moving step may comprise displacing the retainer forward by a displacing means of the retainer and/or the housing. The retainer moving step may comprise obliquely contacting at least one of the retainer and the terminal fitting with the other of the retainer and the terminal fitting. 
     The method further comprises a loose movement preventing step of preventing a loose movement of the retainer from the partial locking position toward the full locking position by contact of the partial locking surface with the partial locking receiving surface, and/or preventing a loose movement of the retainer from the full locking position toward the partial locking position by contact of the full locking surface with the full locking receiving surface. 
     These and other objects, features and advantages of the present invention will become more apparent upon reading of the following detailed description of preferred embodiments and accompanying drawings. It should be understood that even though embodiments are separately described, single features thereof may be combined to additional embodiments. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a section showing a state where terminal fittings and a retainer are detached from a housing in one embodiment of the invention. 
     FIG. 2A is a section with the retainer held at a partial locking position, and FIG. 2B is a section with the retainer held at the partial locking position. 
     FIG. 3A is a section showing a state where the terminal fittings are locked by the retainer held at a full locking position, and FIG. 3B is a section showing a state where the retainer is held at the full locking position. 
     FIG. 4 is a rear view showing a state where the retainer is detached from the housing. 
     FIG. 5 is a fragmentary enlarged section partly cut away showing a state where the retainer is located at the partial locking position. 
     FIG. 6 is a fragmentary enlarged section partly cut away showing a state where the retainer is located at the full locking position. 
     FIG. 7 is a bottom view showing a state where the retainer is detached from and arranged beside the housing. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A connector in accordance with the invention has a housing  10  made e.g. of a synthetic resin, a front-stop  14  made e.g. of a synthetic resin, a plurality of terminal fittings  30 , and a retainer  40  e.g. of a synthetic resin. In the following description, the side of the connector that mates with a mating connector (not shown) is referred to as front side. 
     Cavities  11  extend through the housing  10  from the front to the rear and are arrayed transversely at upper and lower stages. A retainer accommodating chamber  12  is open in the bottom surface of the housing  10  and communicates with the cavities  11 . Resiliently deformable locks  13  are formed at locations in each cavity  11  between the retainer accommodating chamber  12  and the front end of the housing  10 . Each lock  13  cantilevers forwardly from a bottom of the respective cavity  11  and has a front end  13 F that projects into the respective cavity  11  when the lock  13  is in an unbiased locking position shown in FIG.  1 . However, each lock  13  can be deflected resiliently about its rear end away from the respective cavity  11  and into a retracted position shown in chain line in FIG.  6 . The front end  13 F of each lock  13  moves obliquely forward and down in direction DD and traces an arc as the lock  13  is deflected into the retracted position. Thus, the front end  13 F of the lock  13  moves toward the front end of the housing  10  as the lock  13  is deflected into the retracted position. 
     The front-stop member  14  is mounted at the front end of the housing  10  and is formed with recesses  15  that communicate with the front ends of the cavities  11 . Front ends of the properly inserted terminal fittings  30  are accommodated in the recesses  15 . The front ends of the recesses  15  define front-stop surfaces  16  for positioning the terminal fittings  30  at their front-limit positions by contacting front ends  30 A of the terminal fittings  30 . 
     Two slit-shaped locking spaces  17  are open in the bottom surface of the housing  10  and are substantially continuous at the opposite transverse ends of the retainer accommodating chamber  12 . Receiving projections  18 F,  18 R are formed respectively on the front and rear walls of each locking space  17  and are at substantially the same height. Partial locking receiving surfaces  19 F,  19 R are formed on the respective receiving projections  18 F,  18 R and face obliquely forward and down. Full locking receiving surfaces  20 F,  20 R are formed on the upper surfaces of the receiving projections  18 F,  18 R and are substantially parallel to the longitudinal direction of the cavities  11 . 
     Each terminal fitting  30  is narrow and long and is formed by bending a metallic material stamped out into a specified shape. A front section of the terminal fitting  30  defines a box  31  that can be connected with an unillustrated mating terminal. A rear section of the terminal fitting  30  defines a wire connecting portion  33  that can be crimped into connection with a wire  32 , and a middle section of the terminal fitting  30  is a coupling portion  34  that couples the box  31  and the wire connecting portion  33 . An engaging edge  35  is formed by a hole in the bottom of the box  31  and is configured for engagement with the lock  13 . The rear end of the box  31  defines a pushable portion  36  for engagement with the retainer  40 , and the bottom end of the pushable portion  36  is slanted to form a contact portion  36 A. 
     The front end  30 F of the terminal fitting  30  is spaced from the engaging edge  35  along the inserting direction ID by a distance that is slightly less than the distance between the front-stop surface  16  and the front end  13 F of the lock  13  when the lock  13  is at the locking position. The lock  13  inclines to the retracted position (chain line in FIG. 6) while the terminal fitting is being inserted into the housing  10 , but restores resiliently to the locking position (FIG. 1) when the front end  30 F of the terminal fitting  30  contacts the front-stop surface  16 . The properly inserted terminal fitting  30  can make slight loose shaking movements along the inserting and withdrawing directions ID of the terminal fitting  30  between a position where the front end  30 F of the terminal fitting  30  contacts the front-stop surface  16  and position where the front end  13 F of the lock  13  engages the engaging edge  35 . However, the lock  13  prevents the terminal fitting  30  from being withdrawn from the cavity  11 . 
     The retainer  40  is adapted to hold the terminal fittings  30  securely in the housing  10 . The front surface of the retainer  40  is formed with pushers  41  that correspond to the respective cavities  11  at the upper stage. The retainer  40  also is formed with through holes  42  that correspond to the respective cavities  11  at the lower stage. The through holes  42  have bottom walls, and portions of the bottom walls at the front surface of the retainer  40  define pushers  41  that correspond to the cavities  11  at the lower stage. Slanted contacts  41 A are formed on the pushers  41  and are aligned obliquely to both moving direction MD of the retainer  40  and the inserting direction ID of the terminal fittings  30 . 
     Left and right vertical ribs  43  are formed on the rear surface of the retainer  40 , and an escaping recess  21  is formed in the rear wall of the retainer accommodating chamber  12  near the bottom opening for avoiding interference with the ribs  43  when the retainer  40  is at a partial locking position (see FIGS. 2,  5 ). The ribs  43  of the retainer  40  face the escaping recess  21  at the same height when the retainer  40  is at the partial locking position shown in FIG.  5 . An area of the rear wall of the retainer accommodating chamber  12  above the escaping recess  21  and below of the cavities  11  of the lower stage defines a rib receiving surface  22 , and the ribs  43  face the rib receiving surface  22  at the same height when the retainer  40  is at a full locking position (see FIGS. 3,  6 ). A dimension between the front wall of the retainer accommodating chamber  12  and the rib receiving surface  22  substantially equals the thickness of the retainer  40 , including the ribs  43 , along the inserting direction ID. Thus, the retainer  40  can make loose movements in forward and backward directions with respect to the housing  10  while the retainer  40  is at the partial locking position. However, the retainer  40  is prevented from making loose movements in forward and backward directions with respect to the housing  10  while at the full locking position. The ribs  43  of the retainer  40  and the rib receiving surface  22  of the housing  10  form a displacing means  45  for displacing the retainer  40  forward with respect to the housing  10  while the retainer  40  is being moved from the partial locking position to the full locking position. 
     The housing  10  and the retainer  40  both are provided with two pairs of partial locking means  50 F,  50 R and two pairs of full locking means  51 F,  51 R which are arranged at the opposite transverse ends of the retainer  40 . These partial and full locking means are described in detail below. 
     Resilient locks  52 F,  52 R are cantilevered from at each of the opposite ends of the retainer  40  and are spaced apart in forward and backward directions. A locking projection  53 F projects forward from the upper end of each front resilient lock  52 F. A partial locking surface  54 F is formed on the upper surface of each locking projection  53 F and extends oblique to the moving direction MD of the retainer  40  between the partial locking position and the full locking position. A full locking surface  55 F is formed on the bottom surface and extends substantially normal to the moving direction MD of the retainer  40 . On the other hand, a partial locking projection  56  projects back from the upper end of the rear resilient locking piece  52 R, and a locking projection  53 R projects back from a location below the partial locking projection  56 . A partial locking surface  54 R is formed on the upper surface of each locking projection  53 R and extends oblique to the moving direction of the retainer  40 . A full locking surface  55 R is formed on the bottom of each locking projection  53 R and extends substantially normal to the moving direction MD of the retainer  40 . The front locking projections  53 F and the rear locking projections  53 R are at approximately the same height along the moving direction MD. 
     The locking projections  53 F,  53 R of the retainer  40  and the receiving projections  18 F,  18 R of the housing  10  form the partial locking means  50 F,  50 R for preventing the retainer  40  at the partial locking position from moving loosely toward the full locking position, and the full locking means  51 F,  51 R for preventing the retainer  40  at the full locking position from moving loosely toward the partial locking position. 
     The retainer  40  is mounted at the partial locking position in the housing  10  (see FIGS. 2 and 5) before the terminal fittings  30  are inserted into the housing  10 . The two pairs of front and rear locking projections  53 F,  53 R and two pairs of front and rear partial locking surfaces  54 F,  54 R of the retainer  40  contact the receiving surfaces  19 F,  19 R of the receiving projections  18 F,  18 R for partial locking of the housing  10  from below in this state. Thus, the retainer  40  is prevented from moving loosely up toward the full locking position. Further, the partial locking projections  56  contact the full locking receiving surfaces  20 R of the rear receiving projections  18 R from above. Thus, the retainer  40  also is prevented from moving down and out of the housing  10 . Additionally, the pushers  41  of the retainer  40  are retracted down and away from the insertion paths of the terminal fittings  30 . 
     The terminal fittings  30  then are inserted in the inserting direction ID into the corresponding cavity  11  from behind. As a result, each lock  13  is deformed resiliently in the deformation direction DD down to the retracted position by the contact with the bottom surface of the box  31  of the terminal fitting  30  during the insertion. The terminal fitting  30  reaches its proper insertion position when the front end  30 F thereof substantially contacts the front-stop surface  16 . At this point, the front end  13 F of the lock  13  disengages from the bottom surface of the box  31 . Thus, the lock  13  resiliently restores toward the locking position, and reaches a height substantially corresponding to the engaging edge  35  of the terminal fitting  30 . The front end  13 F of the lock  13  is displaced backward during the movement of the lock  13  from the retracted position to the locking position. Consequently, a clearance is formed between the front end  13 F of the lock  13  and the engaging edge  35  along the inserting direction ID (see FIG.  6 ). Therefore, the terminal fitting  30  can shake along the inserting direction ID. 
     Next, the retainer  40  is moved in the moving direction MD from the partial locking position to the full locking position (FIGS. 3,  6 ). As a result, the resilient locks  52 F,  52 R deform and the partial locking surfaces  54 F,  54 R disengage from the partial locking receiving surfaces  19 F,  19 R. The locking projections  53 F,  53 R then move beyond the receiving projections  18 F,  18 R, and the front and rear full locking surfaces  55 F,  55 R engage the full locking receiving surfaces  20 F,  20 R from above. As a result, the retainer  40  is held at the full locking position. 
     The ribs  43  align with and engage the rib receiving surface  22  as the retainer is moved to the full locking position. Thus, the retainer  40  is displaced forward. The slanted guide surfaces  43 A at the upper ends of the ribs  43  enable the ribs  43  to move smoothly into engagement with the rib receiving surface  22 . 
     The terminal fittings  30  may be at their proper insertion positions when the retainer  40  is moved to the full locking position (see FIG.  6 ). In this case, the rear surfaces of the pushable portions  36  of the terminal fittings  30  and the front surfaces of the pushers  41  are at the same position along the inserting direction ID. Thus, the pushers  41  slide in contact with the pushable portions  36  from behind without moving the terminal fittings  30  in the inserting direction ID, and the retainer  40  holds the terminal fittings  30  at their proper insertion positions. 
     On the other hand, the terminal fitting  30  may be behind the proper insertion position (see FIG.  5 ). In this case, the slanted contacts  36 A,  41 A formed at the bottom ends of the rear surfaces of the pushable portions  36  and at the upper edges of the front surfaces of the pushers  41  contact each other obliquely. Thus, the pushers  41  push the pushable portions  36  forward by the inclination of the contacts  36 A,  41 A as the retainer  40  is moved, and the terminal fitting  30  is pushed to the proper insertion position when the retainer  40  reaches the full locking position. 
     The connector of this embodiment has the following effects. 
     The front end  30 F of each properly inserted terminal fitting  30  contacts the corresponding front-stop surface  16 . However, a clearance exists between the engaging edge  35  and the front end  13 F of the lock  13 . Thus, the terminal fitting  30  is permitted to shake in forward and backward directions. The retainer  40  can be moved from the partial locking position to the full locking position while being displaced forward. Thus, the pushers  41  of the retainer  40  contact the properly inserted terminal fittings  30  and hold the terminal fittings  30  at their proper insertion positions. Thus, the terminal fittings  30  are prevented from shaking when the retainer  40  is held at the full locking position. 
     The terminal fitting  30  could be rearward of the proper insertion position as the retainer  40  is being moved to the full locking position. In this case, the slanted contacts  36 A,  41 A engage and push the retainer  40  forward and hence push the terminal fitting  30  toward the proper insertion position. Thus, movement of the retainer  40  to the full locking position is not hindered. 
     The retainer  40  is displaced forward in the inserting direction ID while being moved in the moving direction MD from the partial locking position to the full locking position. Thus, movement of the retainer  40  from the partial locking position to the full locking position allows the retainer  40  to move the terminal fitting  30  towards its proper position. The displacing direction (ID) of the retainer increases engaging areas of the front receiving projections  18 F and the locking projections  53 F. The engaging areas of the full locking receiving surfaces  20  and the full locking surfaces  55 F are larger than those of the partial locking receiving surfaces  19 F and the partial locking surfaces  54 F. Thus, the retainer  40  can be held reliably at the full locking position. 
     The retainer  40  moved to the full locking position does not shake along the inserting direction ID because the ribs  43  contact the rib receiving surfaces  22  and the pushers  41  contact the terminal fittings  30  at their front-limit positions. Therefore, there is no possibility of disengaging the full locking surfaces  55 F,  55 R from the receiving surfaces  20 F,  20 R for full locking due to shaking of the retainer  40  in forward and backward directions. 
     At least two pairs of front and rear partial locking means  50 F,  50 R are provided. Thus, a partial locking function can be effected more reliably as compared to connectors with one pair of partial locking means. Similarly, at least two pairs of front and rear full locking means  51 F,  51 R are provided, and a full locking function can be effected more reliably as compared to connectors with only one pair of full locking means. 
     The partial locking means  50 F,  50 R are at two positions spaced apart in forward and backward directions. Thus, the retainer  40  can be oriented stably at the partial locking position. Further, the two partial locking means  50 F,  50 R are at substantially the same position with respect to vertical direction, there is no possibility that the retainer  40  is inclined with respect to forward and backward directions at the partial locking position. 
     Similarly, the full locking means  51 F,  51 R are at two or more positions spaced apart in forward and backward directions. Thus, the retainer  40  can be oriented stably at the full locking position. Further, the two full locking means  51 F,  51 R are at substantially the same position with respect to the vertical direction. Thus, there is no possibility that the retainer  40  is inclined with respect to forward and backward directions at the full locking position. 
     The locking projections  53 F,  53 R on the retainer  40  function both as the partial locking portions and as the full locking portions. Thus, the retainer  40  has a simpler shape than those with partial and full locking portions are separate. Similarly, the receiving projections  18 F,  18 R in the housing  10  function both as the receiving portions for partial locking and as the receiving portions for full locking. Thus, the housing  10  has a simpler shape than those with partial and full locking portions are separate. 
     The present invention is not limited to the above described and illustrated embodiment. For example, the following embodiments are also embraced by the technical scope of the present invention as defined by the claims. Beside the following embodiments, various changes can be made without departing from the scope and spirit of the present invention as defined by the claims. 
     The locks for locking the terminal fittings are resin locks formed in the housing in the foregoing embodiment. However, the terminal fittings may be locked by metallic locks formed by bending cut portions of the terminal fittings. 
     Both the pushers and the pushable portions are provided with the slanted contacts in the foregoing embodiment. However, only either the pushers or the pushable portions may be provided with the contacts. 
     Although the terminal fittings are female terminal fittings in the foregoing embodiment, they may be male terminal fittings. 
     In the foregoing embodiment, the retainer is displaceable in forward and backward directions when at the partial locking position and is displaced forward when moved from the partial locking position to the full locking position. However, the retainer may be prevented from displacing in forward and backward directions with respect to the housing when at the partial locking position, and the pushers of the retainer may engage the terminal fittings to hold them at their proper insertion positions after the retainer is moved to the full locking position without being displaced forward. 
     Although two stages of terminal fittings are provided, one or more than two stages may be provided.