Patent Publication Number: US-9407025-B2

Title: Connector

Description:
BACKGROUND 
     1. Field of the Invention 
     The present invention relates to a connector. 
     2. Description of the Related Art 
     Japanese Unexamined Patent Publication No. 2013-218902 discloses a connector that has a housing with cavities, terminal fittings to be inserted into the respective cavities from behind and a retainer to be mounted into the housing from the front. A deflectable locking lance is provided at an inner wall of the cavity of the housing and a deflection space for the locking lance is open on the front surface of the housing. A guiding groove is provided on the inner surface of the lower wall of each cavity and extends in a front-back direction. Further, a forwardly open entrance groove is provided on a partition wall between the cavities and extends in the front-back direction of the housing. A lock receiving portion is provided at a position facing the entrance groove. 
     The terminal fitting includes a stabilizer projecting downwardly from the lower surface of a connecting portion. Further, the retainer includes a front wall for covering the front surface of the housing. Ribs project back from the rear surface of the front wall and retaining portions project back from the rear surface of the front wall and side by side with the ribs. 
     In the above configuration, the stabilizer enters the guiding groove to guide an inserting operation of the terminal fitting into the cavity of the housing. Further, the locking lance resiliently locks the connecting portion of the terminal fitting that has been inserted properly into the cavity and primarily prevents a movement of the terminal fitting out of the cavity. On the other hand, the retaining portions enter the deflection spaces for the locking lances when the retainer is mounted into the housing to restrict the deflection of the locking lances. In this way, the movement of the terminal fitting out of the cavity is prevented secondarily. Further, the ribs enter the entrance grooves when the retainer is mounted into the housing and locks on the ribs engage the lock receiving portions to prevent a movement of the retainer out of the housing. 
     The guiding grooves for guiding the insertion of the terminal fittings of the above-described conventional connector and the lock receiving portions for preventing the retainer from coming out are at different positions in the housing. Thus, the structure of a mold for forming the guiding grooves and the lock receiving portions may become complicated and there is difficulty molding small connectors. 
     The invention was completed based on the above situation and aims to provide a connector capable of preventing the complication of the structure of a mold and also dealing with small connectors. 
     SUMMARY OF THE INVENTION 
     The invention is directed to a connector comprising terminal fittings. Each terminal fitting has a stabilizer projecting in a direction intersecting a front-back direction. The connector also has a housing with cavities that extend in the front-back direction and into which the terminal fittings are inserted from behind. Rearwardly open guiding grooves are formed on partition walls between adjacent cavities and communicate with the cavities. The guiding grooves receive the stabilizers to guide insertion of the terminal fittings into the cavities. Communication holes are open on the front ends of the partition walls and communicate with the guiding grooves. The front ends of the guiding grooves are closed. A deflectable locking lance is provided at an inner wall of each cavity and resiliently locks the properly inserted terminal fitting for preventing the terminal fitting from coming out backward. Deflection spaces for the locking lances open forward. A retainer is mounted in the housing from the front and has retaining portions for restricting the deflection of the locking lances by entering the deflection spaces for the locking lances. Locks of the retainer enter the communication holes and lock to the closed end parts of the guiding grooves to prevent the retainer from coming out of the housing. 
     The guiding grooves of the housing guide insertion of the terminal fittings and also have the closed front ends that engage the locks of the retainer to prevent the retainer from coming out of the housing. Thus, the structure of the housing can be simplified as compared with a conventional case where a structure for guiding terminal fittings and a structure locking a retainer are at different positions in a housing. As a result, the mold can be less complex and small connectors can be dealt with. 
     A rubber plug is fit externally on an end part of a wire and is fixed to a rear part of the terminal fitting. A rear part of the cavity has a larger diameter than a front part and defines a rubber plug accommodating portion for receiving the rubber plug in a liquid-tight manner when the terminal fitting is inserted properly in the cavity. The guiding groove communicates with only the front part of the cavity and is in a range to be accommodated in the width of the rubber plug accommodating portion when viewed from behind. Accordingly, the width of the housing is not increased due to the guiding grooves and the connector can be miniaturized. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a plan view in section of a connector of an embodiment of the invention where a retainer is held at a partial locking position with respect to a housing. 
         FIG. 2  is a plan view in section showing the retainer at a full locking position in the housing. 
         FIG. 3  is a side view in section showing the retainer at the full locking position. 
         FIG. 4  is a rear view in section of a cavity part of the housing. 
         FIG. 5  is a front view of the housing. 
         FIG. 6  is a section along A-A of  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION 
     An embodiment of the invention is described with reference to  FIGS. 1 to 6 . A connector of this embodiment includes a housing  10  made of synthetic resin, a retainer  60  made of synthetic resin and terminal fittings  90  made of electrically conductive metal. The housing  10  is connectable to an unillustrated mating housing. In the following description, an end where the mating housing is located with respect to the housing  10  at the start of connection is referred to as a front end concerning a front-back direction and a vertical direction is based on  FIGS. 3 to 5 . Further, a width direction is synonymous with a lateral direction of  FIG. 5  in the following description. 
     As shown in  FIGS. 5 and 6 , the housing  10  includes a housing main body  11  in the form of a flat block in the width direction, a tubular fitting tube  12  surrounds the housing main body  11  and a radially extending coupling  13  connects the fitting tube  12  and the housing main body  11 . A connection space  14  is open between the housing main body  11  and the fitting tube  12  before the coupling  13  to accommodate an unillustrated receptacle of the mating housing. A front part of the housing main body  11  projects farther forward than the front end of the fitting tube  12 . 
     The housing  10  includes a lock arm  15 . As shown in  FIG. 3 , the lock arm  15  has a leg  16  that stands up from a rear part of the upper surface of the housing main body  11  and an arm main body  17  that extends both forward and backward from the upper end of the leg  16 . The arm main body  17  can make a seesaw-like resilient pivotal displacement with the leg  16  as a support. The arm main body  17  locks an unillustrated lock portion of the mating housing when the housing  10  is connected properly to the mating housing to hold the two housings in a connected state. 
     As shown in  FIG. 5 , two protection walls  18  are provided at opposite widthwise sides of the lock arm  15  on the top of the fitting tube  12  and a bridging wall  19  connects the front ends of the protection walls  18  at positions before the lock arm  15 . The upper surfaces of the lock arm  15  is exposed between the protection walls  18  and behind the bridging wall  19 . 
     Cavities  20  penetrate the housing main body  11  in the front-back direction, as shown in  FIG. 6 , and are arranged side by side in a row in the width direction. A rubber plug accommodating portion  21  is formed at a rear part of each cavity  20  and has a circular cross-section that is wider than a front part of the cavity  20 . The front part of each cavity  20  has a substantially rectangular cross-section. As shown in  FIG. 3 , a deflectable locking lance  22  is cantilevered obliquely forward from the lower surface of the inner wall of the front part of the cavity  20 . An area of the housing main body  11  before the locking lances  22  is open as a mold removal space  26 . 
     The terminal fitting  90  is inserted into the cavity  20  of the housing main body  11  from behind and is locked resiliently by the locking lance  22  to be held and retained in the cavity  20  when inserted properly. As shown in  FIGS. 1 and 3 , the terminal fitting  90  includes a rectangular tubular main body  91 , a wire barrel  92  connected to and behind the main body  91  and an insulation barrel  93  connected to and behind the wire barrel  92 . The main body  91  receives a male tab of an unillustrated mating terminal fitting mounted in the mating housing and is connected electrically conductively to the mating terminal fitting when the housing  10  is connected properly to the mating housing. 
     As shown in  FIG. 3 , a stepped lance receiving portion  94  is provided at the lower wall of the main body portion  91  and can lock the locking lance  22  when the terminal fitting  90  is inserted properly. Further, as shown in  FIG. 1 , a laterally projecting stabilizer  95  is cut and bent on one side wall of the main body portion  91 . The stabilizer  95  has a substantially rectangular cross-section when viewed from the front (see  FIG. 4 ). 
     As shown in  FIGS. 1 and 3 , the wire barrel  92  is connected by crimping to a core  112  exposed by removing a coating  111  at an end part of the wire  100 . The insulation barrel  93  is connected by crimping to a rubber plug  120  fit externally on the coating  111  at the end part of the wire  100 . 
     As shown in  FIGS. 1 and 3 , the rubber plug  120  has a cylindrical shape with an outer diameter slightly larger than the main body portion  91 . The inner peripheral surface of the rubber plug  120  is held resiliently in close contact with the outer peripheral surface of the coating  111  of the wire  100  and the rubber plug  120  is inserted into the rubber plug accommodating portion  21  so that the outer peripheral surface thereof is held resiliently in close contact with the inner peripheral surface of the rubber plug accommodating portion  21  when the terminal fitting  90  is inserted properly into the cavity  20 . In this way, the housing main body  11  and the wire  100  are sealed in a liquid-tight manner. Note that an unillustrated seal ring is fit externally on the outer peripheral surface of the housing main body  11 . When the housings are connected properly, the seal ring is sandwiched resiliently between the receptacle of the mating housing and the housing main body  11  to provide liquid tight sealing between the housings. The seal ring contacts a peripheral plate  62  of the retainer  60  to prevent the retainer  60  from coming out forward when the retainer  60  is at a full locking position. 
     As shown in  FIG. 5 , front walls  24  are provided on the front of the housing main body  11 . Each front wall  24  has a U-shaped cross-section and closes an upper part of a front opening of the corresponding cavity  20  while leaving a tab insertion path  23 , into which the male tab of the unillustrated mating terminal fitting is inserted. A tapered guiding surface  25  is provided around the tab insertion path  23  on the front surface of the front wall  24  for guiding the mating tab into the cavity  20 . A lower part of the front of each cavity  20  is open and communicates with the mold removal space  26 . 
     Partition walls  27  are provided in the housing main body  11  between adjacent cavities  20 , as shown in  FIG. 6 . The partition walls include front partition walls  28  in the front parts of the respective cavities  20  and rear partition walls  29  in rear parts of the cavities  20 . The front partition walls  28  are thicker than the rear partition walls  29  at central positions of the cavities  20  in a height direction. As shown in  FIG. 5 , a front part of the front partition wall  28  constitutes a side part of the front wall  24  and defines the upper edge of the mold removal space  26 . 
     A tapered surface  30  is formed on a rear part of each front partition wall  28  and gradually narrows the cavity  20  from the front end of the rear partition wall  29  toward the front, as shown in  FIG. 6 . A guiding groove  31  is provided on one side surface of each front partition wall  28  and communicates with a central part of the cavity  20  in the height direction. Each guiding groove  31  extends in the front-back direction and has a rear end that is open on the tapered surface  30  and a front end that is closed as a closed end part  32  at a position near the front end of the housing main body  11 . The guiding groove  31  is not formed in the rubber plug accommodating portion  21  and has a depth to be accommodated within the width of the rubber plug accommodating portion  21  when viewed from behind, as shown in  FIG. 4 . The guiding groove  31  has a substantially rectangular cross-section and the stabilizer  95  of the terminal fitting  90  can be fit and inserted therein from behind. As shown in  FIG. 6 , the closed end part  32  of the guiding groove  31  is a flat surface extending in the width direction. 
     A communication hole  33  extends in the front-back direction on each front partition wall  28  and communicates with the mold removal space  26 , as shown in  FIGS. 5 and 6 . Each communication hole  33  has an open front end on the front surface of the front wall  24 . Additionally, each communication hole  33  communicates in parallel with the guiding groove  31  from a position corresponding to the closed end  32  of the guiding groove  31  to the rear end and has a rear end closed as a stop  34 . A front surface opening of the communication hole  33  is between the guiding surfaces  25  of adjacent front walls  24 . The stop  34  of the communication hole  33  is a flat end surface extending in the width direction. As shown in  FIG. 6 , the communication hole  33  and the guiding groove  31  also are formed on one of the outer side walls  35  in the same manner as those provided on the partition walls  27 . Of course, the communication hole  33  on the outer side wall  35  is exposed on the outer surface of the housing main body  11  and a rear end thereof is arranged to face the connection space  14 . 
     As shown in  FIGS. 1 and 3 , the retainer  60  is mounted into the housing main body  11  from the front and includes a plate-like front plate  61  extending in the width direction and a peripheral plate  62  projecting back from the outer periphery of the front plate  61 . The retainer  60  is movable in the front-back direction between a partial locking position (see  FIG. 1 ) where the front plate  61  is separated forward from the front surfaces of the front walls  24  of the housing main body  11  and the full locking position (see  FIGS. 2 and 3 ) where the front plate  61  is in contact with the front surfaces of the front walls  24  of the housing main body  11  to cover these front surfaces. 
     As shown in  FIG. 3 , fitting holes  63  penetrate through the front plate  61  and can receive the front walls  24  at the full locking position. Additionally, protecting plates  64  close the front surface openings of the mold removal space  26  and cover the locking lances  22  from front. The protecting plates  64  are arranged below the front walls  24  to face the front walls  24  and define the tab insertion paths  23  together with the front walls  24 . A tapered guiding surface  25  is continuous with the front wall  24  and is provided around the tab insertion path  23  on the front surface of the protecting plate  64 . 
     Retaining portions  65  project from the rear surfaces of the protecting plates  64  of the front plate  61  at positions corresponding to the respective cavities  20  of the housing main body  11 . Each retaining portion  65  is retracted to a position to allow the deflection of the locking lance  22  at the partial locking position and is inserted deeply into the deflection space  36  for the locking lance  22  (see  FIG. 5 ) at the full locking position as shown in  FIG. 3  to restrict deflection of the locking lance  22 . 
     Locking portions  66  project on the rear surface of the front plate  61  at positions corresponding to the respective partition walls  27  and the one outer side wall  35  of the housing main body  11 , as shown in  FIGS. 1 and 2 . Each locking portion  66  is in a plate that can fit into the communication hole  33 . The locking portion  66  corresponding to the one outer side wall  35  is coupled unitarily to the peripheral plate  62 . 
     As shown in  FIGS. 1 and 2 , the locking portions  66  include two full locking portions  67  coupled to the peripheral plate  62  and arranged on opposite widthwise ends and two partial locking portions  68  arranged in a widthwise middle part between the full locking portions  67 . Each full locking portion  67  includes a full locking projection  69  at a position near a front end on a surface facing the guiding groove  31  in a state inserted in the communication hole  33 . On the other hand, the partial locking portion  68  includes a partial locking projection  70  closer to a rear end than the full locking projection  69  on a surface facing the guiding groove  31  in a state inserted in the communication hole  33 . 
     The partial locking projections  70  are slightly longer in the front-back direction than the full locking projections  69 . Further, front and rear surfaces of both the partial locking projections  70  and the full locking projections  69  are tapered inclined surfaces. The front inclined surfaces of the full locking projections  69  have a steeper angle of inclination than the front inclined surfaces of the partial locking projections  70 , and the rear inclined surfaces of the full locking projections  69  and those of the partial locking projections  70  have substantially the same angle of inclination. 
     As shown in  FIG. 1 , the retainer  60  initially is held at the partial locking position with respect to the housing  10 . At the partial locking position, rear ends of the full locking portions  67  are inserted into the communication holes  33  on the opposite widthwise end parts of the housing main body  11  from the front and the full locking projections  69  of the full locking portions  67  are in contact with the front surfaces of the front walls  24  of the housing main body  11  to be lockable. Further, at the partial locking position, rear ends of the partial locking portions  68  are inserted into the communication holes  33  in the widthwise middle part of the housing main body  11  from the front and the partial locking projections  70  of the partial locking portions  68  enter the guiding grooves  31  after being slightly press-fit into the communication holes  33  of the front wall portions  24  and are arranged to contact the closed ends  32  of the guiding grooves  31  to be lockable. In this way, the retainer  60  is held at the partial locking position with a movement in the front-back direction restricted. 
     The terminal fittings  90  are inserted into the cavities  20  of the housing  10  from behind with the retainer  60  at the partial locking position. The stabilizer  95  enters the guiding groove  31  during the insertion and slides on a groove surface of the guiding groove  31  to guide the insertion of the terminal fitting  90 . The stabilizer  95  cannot enter the guiding groove  31  and will interfere with the tapered surface  30 , if the terminal fitting  90  is not in the proper posture, such as a vertically inverted posture, thereby preventing further insertion of the improperly oriented terminal fitting  90  into the cavity  20 . On the other hand, the properly oriented terminal fitting  90  can be inserted into the cavity  20  so that the locking lance  22  is locked resiliently to the lance receiving portion  94  of the main body  91  to hold the terminal fitting  90  in the cavity  20  of the housing  10 . 
     The retainer  60  subsequently is pushed to the full locking position. At this time, the locked state of the full locking projections  69  of the full locking portions  67  and the front surfaces of the front walls  24  is released by a pushing force for pushing the retainer  60  to the full locking position. As shown in  FIG. 2 , when the retainer  60  reaches the full locking position, the locking projections  66  are inserted deeply into the communication holes  33  and the rear ends thereof are arranged to contact the stops  34  of the communication holes  33 . Further, at the full locking position, the full locking projections  69  pass through the communication holes  33  of the front walls  24 , enter the guiding grooves  31  and contact the closed end parts  32  of the guiding grooves  31 . In this way, the retainer  60  is held at the full locking position with movement in the front-back direction restricted. Further, when the retainer  60  reaches the full locking position, as shown in  FIG. 3 , the retaining portions  65  enter the deflection spaces  36  for the locking lances  22  and contact the lower surfaces of the locking lances  22 . In this way, the locking lances  22  cannot deflect so that the terminal fittings  90  are retained secondarily in the cavities  20  of the housing  10 . 
     The communication holes  33  are formed by pin-like mold parts to be pulled out forward. On the other hand, the guiding grooves  31  are formed together with the cavities  20  and the like by pin-like mold parts to be pulled out backward. In the case of this embodiment, the closed end parts  32  of the guiding grooves  31  function as a retaining structure for preventing the retainer  60  from coming out forward from the housing main body  11  by locking the partial locking projections  70  of the partial locking portions  68  and the full locking projections  69  of the full locking portions  67 . A dedicated retaining structure for preventing the retainer  60  from coming out forward could be provided instead of the closed end parts  32  of the guiding grooves  31 . However, a mold part for forming that dedicated retaining structure would have to be provided separately from a mold part for forming the guiding grooves  31 , thereby making a mold structure complicated. In contrast, the retaining structure can be formed by the mold part for molding the guiding grooves  31  so that the mold structure is less complicated. As a result, it becomes possible to deal with the miniaturization of the connector. 
     The guiding groove  31  communicates only with the front part of the cavity  20  and is formed in such a range as to be accommodated within the width of the rubber plug accommodating portion  21  when viewed from behind, as shown in  FIG. 4 . Thus, the width of the housing  10  does not become particularly large due to the guiding grooves  31  and the connector can be miniaturized. 
     The invention is not limited to the above described embodiment. For example, the following embodiments also are included in the scope of the invention. 
     When the retainer is at one of the partial and full locking positions, either the partial locking portions or the full locking projections may lock the closed ends of the guiding grooves to prevent the retainer from coming out of the housing. 
     The invention is also applicable to non-waterproof connectors in which a terminal fitting is not fixed to a rubber plug externally fitted on an end part of a wire. 
     LIST OF REFERENCE SIGNS 
     
         
           10  . . . housing 
           20  . . . cavity 
           21  . . . rubber plug accommodating portion 
           22  . . . locking lance 
           27  . . . partition wall 
           31  . . . guiding groove 
           32  . . . closed end part 
           33  . . . communication hole 
           36  . . . deflection space 
           60  . . . retainer 
           61  . . . front plate portion 
           65  . . . retaining portion 
           66  . . . locking portion 
           67  . . . full locking portion 
           68  . . . partial locking portion 
           90  . . . terminal fitting 
           95  . . . stabilizer 
           100  . . . wire 
           120  . . . rubber plug