Patent Publication Number: US-9431744-B2

Title: Connector with retainer having extended pushing surface and posture correcting portion

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a connector. 
     2. Description of the Related Art 
     A conventional connector uses a locking lance and a retainer for doubly locking a terminal fitting in a housing. The retainer includes a body with a terminal locking portion to be locked to the terminal fitting and a housing locking portion to be locked to the housing. In recent years, there has been a strong request to miniaturize connector housings and retainers also have been miniaturized in response to this request. As a result, a pushing surface used to push a retainer into the housing becomes smaller, thereby making a pushing operation difficult. 
     Japanese Unexamined Patent Publication No. H10-92502 addresses this difficulty by providing a connector with a pushing surface that extends forward from the upper surface of a body via a coupling in a central part. However, a pushing surface that extends toward the front in this way causes the retainer to incline so that the extended front is lowered when being pushed into the housing. This makes it difficult to mount the retainer smoothly. 
     The invention was completed based on the above situation and aims to provide a connector enabling a smooth mounting operation of a retainer even if a pushing surface is extended. 
     SUMMARY OF THE INVENTION 
     The invention is directed to a connector that includes a housing formed with cavities and terminal fittings accommodated in the cavities. The housing includes a retainer insertion hole and the connector further includes a retainer that is to be inserted into the retainer insertion hole. The retainer is configured to lock and retain the terminal fittings in a mounted state in the cavities. The retainer includes a body with a housing lock to be locked to an inner part of the housing and terminal locks to be locked to the terminal fittings. A pushing surface is formed at a rear end of retainer in an inserting direction of the retainer into the housing and an extended portion extends from the pushing surface in a connecting direction that intersects the inserting direction of the retainer. The extended portion is substantially continuous and flush with the pushing surface. A posture correcting portion restricts inclination of the retainer by contacting the housing in a direction along an extending direction of the extended portion when the retainer is mounted into the housing. 
     The pushing surface is extended by forming the extended portion from the body in the direction intersecting the inserting direction. Thus, the retainer easily can be pushed in a proper direction even if the retainer is made smaller. Further, the extended portion is extended toward one side of the body. Thus, the entire retainer may be inserted in a posture inclined with respect to an extending direction of the extended portion when the extended portion is pushed. However, the posture correcting portion contacts the extended portion in the extending direction of the extended portion when the retainer is inserted into the retainer insertion hole to restrict inclination of the retainer. Thus, the retainer can be inserted into the retainer insertion hole in a proper posture so that the retainer can be mounted smoothly. 
     Two of the housing locks preferably are formed on the body and extend along the inserting direction of the retainer. The locks preferably are deflectable in a width direction. The posture correcting portion preferably extends along the inserting direction of the retainer between the housing locks in the body and can fit into a recess formed by cutting a partition wall between the cavities that are adjacent in the width direction along the connecting direction. 
     There is concern that the laterally deflectable housing locks may permit the retainer to rattle in the width direction. However, the posture correcting portion is fit into the recess of the partition wall in the mounted state of the retainer and is sandwiched between the terminal fittings accommodated in the adjacent cavities. Thus, the posture correcting portion contacts the terminal fitting to restrict displacement of the retainer in the width direction. The posture correcting portion also contacts front and rear walls of the recess in the connecting direction to restrict rattling of the retainer in the connecting direction. 
     The posture correcting portion contacts the housing locks when the housing locks are deformed within a resiliency limit, and thereby prevents excessive deflection of the housing locks. 
     The retainer may have a protruding backlash restricting portion, and the housing may have a positioning recess that receives and tightly holds the backlash restricting portion in the connecting direction when mounting the retainer into the housing. Thus, the retainer is positioned in the connecting direction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view in section when a retainer is at a partial locking position in a male connector. 
         FIG. 2  is a side view in section when the retainer is at a full locking position. 
         FIG. 3  is a bottom view of a male connector housing. 
         FIG. 4  is a bottom view of the male connector when the retainer is at the partial locking position or at the full locking position. 
         FIG. 5  is a bottom view of the retainer. 
         FIG. 6  is a front view of the retainer. 
         FIG. 7  is a plan view of the retainer. 
         FIG. 8  is an enlarged section showing a state where a posture correcting portion of the retainer is fitted in a recess of a partition wall to hold the retainer in a proper posture. 
         FIG. 9  is a section along A-A of  FIG. 4  when the retainer is at the partial locking position. 
         FIG. 10  is a section along A-A of  FIG. 4  when the retainer is at the full locking position. 
         FIG. 11  is a side view in section showing a state where a detecting member is at an initial position in a female connector. 
         FIG. 12  is a rear view of a female connector housing. 
         FIG. 13  is a side view in section of the female connector housing. 
         FIG. 14  is a view showing a cross-section along B-B of  FIG. 12  in a vertically inverted manner. 
         FIG. 15  is a side view of the detecting member. 
         FIG. 16  is a front view of the detecting member. 
         FIG. 17  is a plan view of the detecting member. 
         FIG. 18  is a view, corresponding to  FIG. 14 , when the detecting member is at the initial position. 
         FIG. 19  is a view, corresponding to  FIG. 14 , when the detecting member is at a detecting position. 
         FIG. 20  is a side view in section showing a state where the male and female connectors are properly connected. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A specific embodiment of a connector of the invention is described with reference to the drawings. Note that, in the following description, front and rear ends in a connecting direction CD of male and female connectors are referred to as a “front”and a “rear” and a direction extending from a front to a back of the plane of  FIG. 1  is referred to as a “width direction ” WD. 
     A male connector in accordance with the invention is identified by the letter M and includes a male housing  1  made of synthetic resin. A rear end of the male housing  1  in the connecting direction CD to a female connector F defines a terminal accommodating portion  2 , and a rectangular tubular receptacle  3  is formed at a front end. As shown in  FIGS. 9 and 10 , two cavities  4  are arranged side by side in the width direction WD in the terminal accommodating portion  2 . Each cavity  4  is capable of accommodating a male terminal fitting  5 , and a locking lance  6  is provided substantially in a central part in the cavity  4  for primarily locking the male terminal fitting  5 . As shown in  FIGS. 1 and 2 , the locking lance  6  is cantilevered obliquely forward and is resiliently deformable in a vertical direction in  FIGS. 1 and 2 . 
     Tabs  5 A of the male terminal fittings  5  are arranged side by side in the width direction and project into the receptacle  3 . A lock  7  projects down at a widthwise central part of the upper side of the opening edge of the receptacle  3 . 
     A retainer insertion hole  8  is open on the lower surface of the terminal accommodating portion  2  at a position behind the locking lances  6  and communicates with the cavities  4 . As shown in  FIGS. 1 and 3 , in an area of the lower surface of the terminal accommodating portion  2  located before the retainer insertion hole  8  and extending up to the receptacle  3 , a widthwise central part is formed to be slightly higher while leaving opposite side edge parts in the width direction. Thus, two elongated projections  9  are formed on and along the opposite widthwise side edges of the lower surface of the terminal accommodating portion  2  (see  FIG. 3 ). The front ends of both elongated projections  9  are continuous and flush with the lower surface of the receptacle  3 , and the rear ends thereof are located at positions slightly before the rear opening edge of the retainer insertion hole  8  (see  FIGS. 1 and 3 ). An accommodating frame  12  for accommodating extended portions  11  of a retainer  10  to be described later projects on a side of the lower surface of the terminal accommodating portion  2  behind the retainer insertion hole  8 . 
     The accommodating frame  12  has a rear wall  12 A extending over the entire width of the terminal accommodating portion  2 , two side walls  12 B and a center wall  12 C. The side walls  12 B extend forward from the opposite widthwise ends of the rear wall  12 A and are arranged on the same straight lines as the elongated projections  9 . The center wall  12 C extends forward from a widthwise central part of the rear wall  12 A, and the heights of the walls  12 A,  12 B and  12 C are substantially flush with a part between the elongated projections  9 . Further, the front ends of the opposite side walls  12 B are slightly behind the front end of the center wall  12 C and two positioning recesses  13  are defined between the front ends of the side walls  12 B and the rear ends of the elongated projections  9 . 
     Further, a cut recess  15  is formed at a position of a partition wall  14  between the cavities  4  in an arrangement direction where the retainer insertion hole  8  is open and has a width substantially equal to the width of the retainer insertion hole  8  in a front-back direction (see  FIGS. 3 and 8 ). 
     As shown in  FIGS. 9 and 10 , partial lock receiving portions  16  and full lock receiving portions  17  are provided on widthwise outer wall surfaces of a wall of the retainer insertion hole  8  while being paired in the width direction. The partial lock receiving portions  16  are provided at shallow positions in the retainer insertion hole  8  and the full lock receiving portions  17  are provided at positions deeper than the partial lock receiving portions  16 . The partial lock receiving portions  16  are for holding the retainer  10  at a partial locking position (position shown in  FIGS. 1 and 9 ) and the full lock receiving portions  17  are for holding the retainer  10  at a full locking position (position shown in  FIGS. 2 and 10 ). 
       FIGS. 5 to 7  show the retainer  10  of the male connector M. The retainer  10  is formed unitarily of synthetic resin to define a body  18  for locking the male terminal fittings  5  and the extended portions  11  for extending a pushing surface  19  of the retainer  10 . As shown in  FIG. 4 , the entire retainer  10  can fit into the accommodating frame  12  of the male housing  1  in an inserting direction ID, and the lower surface (pushing surface  19 ) of the retainer  10  is substantially flush with the elongated projections  9  and the respective walls of the accommodating frame  12  when the retainer is at the full locking position. 
     A flat body side pushing surface  19 A is formed on the lower surface of the body  18 . Two legs  20  (housing locks) project up on opposite widthwise side parts of the upper surface of the body  18 . Locking claws  21  project on outer surfaces of the legs  20  near the tips of the legs  20 . The legs  20  can be deformed resiliently toward each other so that the locking claws  21  can be locked releasably to the partial lock receiving portions  16  and the full lock receiving portions  17  described above. 
     Sides of the legs  20  closer to the tips than the locking claws  21  define locking protrusions  22  capable of locking the male terminal fittings  5 . The locking protrusions  22  are below the corresponding cavities  4  when the retainer  10  is at the partial locking position shown in  FIGS. 1 and 9 . Thus, at the partial locking position, the male terminal fittings  5  can be inserted into and withdrawn from the cavities  4 . On the other hand, the locking protrusions  22  are in the corresponding cavities  4  when the retainer  10  is at the full locking position, as shown in  FIGS. 2 and 10 , to lock the male terminal fittings  5  and doubly retain the male terminal fittings  5  together with the locking lances  6 . 
     A posture correcting portion  23  projects up in a widthwise central part of the upper surface of the body portion  18  between the legs  20 . The posture correcting portion  23  has a width equal to the width of the body  18  in the front-back direction. As shown in  FIG. 6 , a narrow portion  23 A is formed at a tip and is narrow in the width direction. When the retainer  10  is at the full locking position, the narrow portion  23 A is fit in the recess  15  in the partition wall  14  between the cavities  4 . A width of the narrow portion  23 A in the front-back direction is slightly less than the width of the recess  15  in the front-back direction. Thus, an inclined posture of the entire retainer  10  in the front-back direction can be restricted by the contact of the front or rear surface of the narrow portion  23 A with the front or rear surfaces of the recess  15 . Further, a thickness of the narrow portion  23 A in the width direction is substantially equal to the width of the partition wall  14 . Thus, when the retainer  10  is at the full locking position, the narrow portion  23 A constitutes a part of the partition wall  14 . 
     The narrow portion  23 A also has an excessive deformation preventing function of preventing the leg portions  20  from being deformed excessively by contacting the widthwise inner surfaces of the legs  20  when the legs  20  are resiliently deformed inwardly (toward each other) within a resiliency limit. 
     The extended portions  11  integrally protrude back from the body  18 . Extended-portion side pushing surfaces  19 B extend continuously on the upper surfaces of the extended portions  11  and are flush with the body side pushing surface  19 A of the body  18 . As shown in  FIG. 5 , the extended portions  11  are forked in the width direction via a U-shaped groove  24  that extends in the front-back direction from the rear end edge. As shown in  FIG. 4 , the center wall  12 C of the accommodating frame  12  is fit tightly into the U-shaped groove  24  of the retainer  10  at the full locking position. As shown in  FIG. 5 , backlash filling projections  25  project in the width direction on widthwise outer side surfaces of the extended portions  11 . When the retainer  10  is at the full locking position, the extended portions  11  are fit between the center wall  12 C and the opposite side walls  12 B and the backlash filling projections  25  are squeezed by the inner surfaces of the opposite side walls  12 B. In this way, the extended portions  11  are sandwiched tightly between the center wall  12 C and the side walls  12 B and the entire retainer  10  can be held without play. 
     Two backlash restricting portions  26  project outward in the width direction on boundaries between the extended portions  11  and the body  18  on opposite side parts of the retainer  10  in the width direction. When the retainer  10  is at the full locking position, the both backlash restricting portions  26  are fit tightly fitted into the corresponding positioning recesses  13  of the male housing  1  so that the retainer  10  is held without play in the front-back direction. 
     The female connector F includes a female housing  27  made of synthetic resin and formed to fit into the receptacle  3  of the male housing  1 . As shown in  FIG. 12 , two cavities  28  are formed side by side in the width direction in the female housing  27 . As shown in  FIG. 11 , the cavities  28  penetrate in the front-back direction, and female terminal fittings  29  are insertable therein through rear ends, and tab insertion holes  30  are open on the front ends of the cavities  28  for receiving the tabs  5 A of the male terminal fittings  5 . A deflectable locking lance  6  is cantilevered obliquely forward from a lengthwise central part of each of the cavities  28  and is capable of locking the female terminal fitting  29 . 
     As shown in  FIG. 11 , a retainer insertion hole  31  is open on the lower surface of the female housing  27  behind the locking lances  6 . A peripheral structure including the retainer insertion hole  31  and a structure of a retainer  32  to be mounted into the retainer insertion hole  31  are as in the already described male connector M, and repeated description is omitted. 
     As shown in  FIG. 11 , a lock arm  33  is provided on the upper surface of the female housing  27  for locking the male and female housings  1 ,  27  in a connected state. The lock arm  33  is cantilevered back from the front end of the female housing  27  and is resiliently deformable down with a front end part as a support. A lock projection  34  projects on the upper surface of a lengthwise central part of the lock arm  33 . Two couplings  35  are connected to the lock arm  33  to extend back from opposite sides of the lock projection  34 . The rear ends of the couplings  35  are slightly elevated and coupled to form an unlocking portion  36 . The lock projection  34  is locked to the lock  7  of the receptacle  3  when the male and female housings  1 ,  27  are connected properly to lock the male and female housings  1 ,  27  in the connected state. 
     As shown in  FIG. 12 , two lock arm protection walls  37  stand on the upper surface of the female housing  27  at opposite sides of the lock arm  33  in the width direction. The lock arm protection walls  37  extend back in the front-back direction from a front end part of the upper surface of the female housing  27  and the rear ends thereof are located slightly before the rear end of the unlocking portion  36 . In a side view of the female housing  27 , the lock arm protection walls  37  have a height so that only the lock projection  34  and the unlocking portion  36  project up (see  FIG. 13 ). 
     Two detector protection walls  38  stand behind the lock arm protection walls  37  on the upper surface of the female housing  27 . A space defined by the detector protection walls  38  and the upper surface of the female housing  27  defines an accommodation space for a detector  39 . The detector protection walls  38  are located at outer sides of the lock arm protection walls  37  in the width direction, as shown in  FIG. 12 , and the rear end surfaces of the lock arm protection walls  37  are located at inner sides of the detector protection walls  38  in the width direction, as shown in  FIG. 14 . 
     As shown in  FIG. 12 , upper ends of the detector protection walls  38  are bent substantially at a right angle to extend inward. Further, upper end parts of the front ends of the both detector protection walls  38  project up and are bent in to form inversion preventing portions  4  that face each other in the width direction. Contrary to this, opposite side parts of the unlocking portion  36  of the lock arm  33  in the width direction protrude out in the width direction to respectively form jaws  41 . Thus, the jaws  41  can contact inner sides of the inversion preventing portions  40  when the lock arm  33  is deformed up so that warping deformation of the lock arm  33  beyond its resiliency limit can be prevented. 
     Lower parts of the rear ends of the detector protection walls  38  protrude out in the width direction and back to form protruding frame portions  42 . As shown in  FIG. 12 , the protruding frame portions  42  have C shapes or inverted C shapes open inward in a rear view of the female housing  27 . 
     As shown in  FIG. 13 , first and second lock receiving portions  43 ,  44  are provided on the inner surfaces of the detector protection walls  38  while being paired in the width direction for restricting backward movement of the detector  39  at an initial position and a detecting position. As shown in  FIG. 12 , the lock receiving portions  43 ,  44  are displaced in a height direction so as not to overlap each other in the height direction in the rear view. Thus, the lock receiving portions  43 ,  44  can be molded by removing a mold in the front-back direction. 
     As shown in  FIG. 14 , the lock receiving portions  43 ,  44  are located more outward in the width direction than backward extensions of the lock-arm protection walls  37 . The first lock receiving portions  43  are connected to a rear part of the upper wall of the female connector housing  27  and are at lower positions, as shown in  FIG. 13 . The first lock receiving portions  43  are designed to prevent the detector  39  from being detached backward from the initial position. As shown in  FIG. 14 , the rear surfaces of the first lock receiving portions  43  are formed into tapered surfaces  43 A, but the front surfaces thereof are formed into upright lock receiving surfaces  43 B. 
     The second lock receiving portions  44  are located before the first lock receiving portions  43  and are at higher positions to make a backward movement of the detector  39  from the detecting position difficult. As shown in  FIG. 14 , both front and rear surfaces of the second lock receiving portions  44  are formed into tapered surfaces  44 A,  44 B. However, the front and rear tapered surfaces  44 A,  44 B are inclined toward opposite sides and the front tapered surfaces  44 B are slightly steeper and closer to upright. 
       FIGS. 15 to 17  show the detector  39 . The detector  39  is mounted into the female housing  27  for movement between the initial position shown in  FIGS. 11 and 18  and the detecting position shown in  FIGS. 19 and 20 . The detector  39  can detect whether or not the male and female connectors M, F are connected properly based on whether the detector  39  can be pushed from the initial position to the detecting position. 
     The detector  39  is molded unitarily of synthetic resin to include a base  45  and a resilient arm  46  coupled to the front surface of the base  45 . The resilient arm  46  is a substantially rectangular bar that is cantilevered forward and is resiliently deformable in the height direction with a base end as a support. In a natural state, the resilient arm  46  is inclined up toward the front. 
     A rectangular block-shaped protrusion  47  projects up on an upper part of the front end of the resilient arm  46 . A widthwise central part of the upper surface of the protrusion  47  has a raised rib that forms an auxiliary protrusion  48 . A contact portion  49  projects forward on a lower part of the front end surface of the resilient arm  46 . When the detector  39  is at the initial position as shown in  FIG. 11 , the contact portion  49  is located in an accommodation space S defined below the lock projection  34  of the lock arm  33 . Thus, when the lock arm  33  is resiliently deformed down at the time of connecting the male and female connectors M, F, the contact portion  49  is pushed down by the lower surface of the lock projection  34 . Thus, the resilient arm  46  is deformed resiliently down as the lock arm  33  is deformed resiliently down. 
     As shown in  FIG. 11 , a tapered guide surface  50  is formed on the upper surface of the protrusion  47  and is inclined up toward the back. Further, a substantially upright movement restricting surface  51  is formed on the front surface of the protrusion  47 . The movement restricting surface  51  faces the tip surface of the lock projection  34  and can come into contact therewith when the detector  39  is at the initial position. Thus, inadvertent movement of the detector  39  from the initial position to the detecting position is restricted. 
     The lock projection  34  slides in contact with the lock protrusion  7  of the receptacle  3  and the lock arm  33  is pushed down while the male and female connectors M, F are being connected. Associated with this, the resilient arm  46  also is pushed down. The lock arm  33  returns to an initial state when the male and female connectors M, F are connected properly. However, since the auxiliary protrusion  48  is pushed by the lock protrusion  7  of the receptacle  3 , the resilient arm  46  is held in a pushed-down state. As a result, a contact state of the movement restricting surface  51  and the tip surface of the lock projection  34  is released and the detector  39  can move forward toward the detecting position. 
     The rear surface of the base  45  defines a pushing wall  52 . As shown in  FIGS. 15 and 16 , opposite side parts of the pushing wall  52  in the width direction have a step shape in the height direction and lower end parts thereof define first steps  52 A that protrude most outward. The first steps  52 A can move in the protruding frames  42  while the detector  39  moves between the initial position and the detecting position. Sliding projections  53  with pointed tips project on the upper surfaces of the first steps  52 A and function to reduce sliding resistance when the detector  39  is pushed by coming into substantially point contact with ceiling surfaces in the protruding frames  42 . Further, second steps  52 B of the pushing wall  52  are higher than the upper surface of the base  45 , and two side walls  54  extend forward from the front surfaces of the second steps  52 B. The side walls  54  are formed to fit into spaces at inner sides of the detector protection walls  38  of the female housing  27 . 
     As shown in  FIG. 17 , two slits  55  are formed between front end parts of the side walls  54  and the base  45  to extend from the front end surfaces of the side walls  54 , and two deflectable locking arms  56  are formed at outer sides of the slits  55  in the width direction. 
     The locking arms  56  are formed to be deflectable inwardly in the width direction. Further, as shown in  FIG. 16 , first and second claws  57  and  58  are provided one above the other on tip parts of the locking arms  56  while projecting outward. The first claws  57  are located at lower positions and can be locked to the first lock receiving portions  43  of the female housing  27 . The rear surfaces of the first claws  57  are formed into upright locking surfaces  59 , as shown in  FIG. 15 , and are locked to the lock receiving surfaces  43 B of the first lock receiving portions  43  when the detector  39  is at the initial position. At this time, the locking surfaces  59  and the lock receiving surfaces  43 B, which are both upright surfaces, are locked to each other. Therefore a backward detachment of the detector  39  located at the initial position is restricted strongly. 
     Conversely, both front and rear surfaces of the second claws  58  are tapered surfaces. The front surfaces  58 A extend in the width direction, i.e. surfaces extending along a direction perpendicular to a pushing direction of the detector  39 . Accordingly, when the detector  39  is at the initial position, the second claws  58  are in contact with the rear surfaces of the second lock receiving portions  44 , as shown in  FIG. 18 , thereby restricting a forward movement of the detector  39  in an auxiliary manner. Further, when the detector  39  is at the detecting position, the front end surfaces  58 A face the rear end surfaces of the lock-arm protection walls  37  and can come into contact therewith while the second claws  58  are locked to the second lock receiving portions  44  as shown in  FIG. 19 , thereby preventing the detector  39  from being pushed further forward from the detecting position. 
     As shown in  FIGS. 18 and 19 , both locking arms  56  are located substantially on backward extensions of the lock-arm protection walls  37  when the detector  39  is at the initial position and the detecting position. When being resiliently deformed inwardly, both locking arms  56  cross these extensions toward widthwise inner sides. In this way, dead spaces behind the lock-arm protection walls  37  can be utilized as deflection spaces for the locking arms  56 . 
     The retainer  10  is held in a partly locked state, as shown in  FIG. 9 , when mounting the male terminal fittings  5  into the male housing  1 . At this time, the locking protrusions  22  of the legs  20  are both retracted outward from the cavities  4 . Therefore the male terminal fittings  5  can be inserted into the cavities  4 . The male terminal fittings  5  inserted to proper positions are locked primarily by the locking lances  6 . 
     The pushing surface  19  of the retainer  10  then is pushed in the inserting direction ID, and the legs  20  deform resiliently inward to unlock the locking claws  21  from the partial lock receiving portions  16 . Thus, the entire retainer  10  is inserted into the retainer insertion hole  8  in the inserting direct ID. When the retainer  10  reaches the full locking position, the locking claws  21  are locked to the full lock receiving portions  17  and the locking protrusions  22  are inserted into the cavities  4  to lock the male terminal fittings  5 . Therefore the male terminal fittings  5  are retained doubly by the locking protrusions  22  together with the locking lances  6 . 
     Note that an operation of mounting the female terminal fittings  29  into the female connector housing  27  can be performed in the same manner as described above. 
     The detector  39  is held at the detecting position in the female connector F before being connected to the male connector M. When the male and female connectors M, F are connected in this state, a tip side of the female housing  27  is fit into the receptacle  3  and the lock projection  34  of the lock arm  33  contacts the front end of the lock protrusion  7  of the receptacle  3  in this connecting process. The lock arm  33  receives a downward pushing force from the lock protrusion  7  and deforms resiliently down as the connecting operation progresses. The contact portion  49  of the resilient arm  46  of the detector  39  also receives a downward pushing force as the lock arm  33  is pushed down and is deformed resiliently down. 
     The male and female terminal fittings  5 ,  29  are connected properly when the male and female connectors M, F are connected to a proper depth and the lock arm  33  returns. Thus, the lock projection  34  is locked to the inner surface of the lock protrusion  7  of the receptacle  3 . At this time, the lock protrusion  7  of the receptacle  3  is in contact with the auxiliary protrusion  48  of the resilient arm  46 . Thus, the resilient arm  46  is kept resiliently deformed down. At this time, a contact state of the movement restricting surface  51  of the resilient arm  46  and the tip surface of the lock projection  34  of the lock arm  33 , i.e. a movement restricted state of the detector  39 , already is released. Thus, the guide surface  50  of the protrusion  47  of the resilient arm  46  slides in contact with the lower edge of the tip of the lock projection  34  of the lock arm  33  when the pushing wall  52  is pushed. Thus, the detector  39  reaches the detecting position while pushing the resilient arm  46  farther down. At this position, the protrusion  47  of the resilient arm  46  is inserted between the lock projection  34  of the lock arm  33  and the upper surface of the female housing  27  to be held substantially in contact with both. Thus, the deflection of the lock arm  33  in an unlocking direction is restricted, and the male and female connectors M, F are locked reliably in the connected state. 
     Further, when being pushed before reaching the detecting position, the detector  39  is no longer held at the initial position where the first claws  57  of the locking arms  56  and the first lock receiving portions  43  are locked to each other. Then, the locking arms  56  are deflected inward and the second claws  58  move over the second lock receiving portions  44 . When the detector  39  reaches the detecting position, the second claws  58  are locked to the second lock receiving portions  44  and the front end surfaces  58 A of the second claws  58  contact the rear end surfaces of the lock-arm protection walls  37 , thereby preventing the detector  39  from moving any farther forward. 
     The retainer  10  is configured so that the extended portions  11  are provided to extend from the body  18  and the extended portion side pushing surfaces  19 B are formed in addition to the body side pushing surface  19 . This enables the entire retainer  10  to be pushed easily even if the retainer  10  is small. Further, since the pushing surface  19  is extended toward one side (rear side) from the body  18 , an insertion posture into the retainer insertion hole  8  tends to be inclined. However, the posture correcting portion  23  is provided and the retainer  10  can be corrected to have a proper insertion posture instead of having an inclined posture by fitting the tip part of the posture correcting portion  23  into the cut recess  15  of the partition wall  14  (see  FIG. 8 ). 
     Since the posture correcting portion  23  is provided between the legs  20  in the retainer  10 , the posture correcting portion  23  can also function to prevent excessive deformation of both legs  20 . 
     The backlash filling projections  25  project on the widthwise side surfaces of both extended portions  11  of the retainer  10  and are squeezed by the inner surfaces of the opposite side walls when the retainer  10  is at the full locking position. Thus, the extended portions  11  are sandwiched tightly between the center wall and the side walls and the entire retainer  10  can be held without play in the width direction. Furthermore, the backlash restrictions  26  project out in the width direction on the retainer  10  and fit substantially tightly into the corresponding positioning recesses  13  of the male housing  1  when the retainer  10  is at the full locking position. Thus, the retainer  10  can be held without play in the front-back direction. 
     The locking arms  56  of the female connector F are located substantially on the backward extensions of the lock-arm protection walls  37  when the detector  39  is at the initial position and the detecting position. When deformed resiliently inward, both locking arms  56  cross these extensions toward the widthwise inner sides. Specifically, the locking arms  56  are arranged utilizing the dead spaces behind the lock-arm protection walls  37  and are resiliently deformed inward. Thus, the connector can be smaller in the width direction as compared with locking arms that are deformed resiliently outward. 
     In the female housing  27 , since the first and second lock receiving portions  43 ,  44  for holding the detector  39  at the initial position and the detecting position are displaced so as not to overlap in the height direction, these can be formed by a mold that is opened and closed in the front-back direction. Thus, a mold structure for the female housing  27  can be simplified. 
     When the detector  39  is at the initial position, the tip of the resilient arm  46  of the detector  39  is in contact with the lock arm  33  and the second claws  58  of the locking arms  56  are in contact with the rear surfaces of the second lock receiving portions  44 . Thus, a forward movement is restricted reliably at the initial position. Further, at the initial position, the first claws  57  are locked to the first lock receiving portions  43  and the locking surfaces and the lock receiving surfaces thereof are upright surfaces. Thus, a situation where the detector  39  is detached outwardly at the initial position can be prevented reliably. 
     When the detector  39  is at the detecting position, the front end surfaces  58 A of the second claws  58  of the detector  39  are in contact with the rear end surfaces of the lock-arm protection walls  37  so that a forward movement can be restricted. Simultaneously, the second claws  58  are locked to the front surfaces of the second lock receiving portions  44  to prevent a return to the initial position. 
     The invention is not limited to the above described and illustrated embodiment. For example, the following embodiments are also included in the technical scope of the present invention. 
     Although the extended portions of the retainer are extended toward one side (rear side) of the body in the above embodiment, they may be extended toward both front and rear sides. 
     Although the posture correcting portion of the retainer also functions to prevent excessive deformation of the both legs in the above embodiment, a posture correcting function and an excessive deformation preventing function may be set at different positions. 
     Although the posture correcting portion of the retainer is locked to the cut recess formed on the partition wall to correct the posture of the retainer in the above embodiment, it may be locked at a position other than the partition wall. 
     Although the deflection of the lock arm is restricted when the detector reaches the detecting position in the above embodiment, the deflection may not be necessarily restricted.