Abstract:
A lock hole ( 22 ) in the form of a window is formed to penetrate a front end portion of a lock arm ( 15 ) resiliently displaceable like a seesaw. In a state where two housings ( 10, 50 ) are not connected yet, a movement of the detector ( 30 ) to a detection position is prevented by such engagement of a latching projection ( 39 ) with the lock hole ( 22 ) as not to move any further forward. A pair of reinforcing ribs ( 23 ) extending from the front end of the lock arm ( 15 ) to a position slightly behind inclination supporting legs ( 16 ) of the lock arm ( 15 ) and arranged at the opposite widthwise sides of the lock hole ( 22 ) are formed to project from the lock arm ( 15 ). The reinforcing ribs ( 23 ) increase the rigidity of the front end portion of the lock arm ( 15 ).

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The invention relates to a connector with a connection detecting function and to a connector assembly. 
   2. Description of the Related Art 
   U.S. Pat. No. 7,252,530 discloses a connector with a first housing that is connectable with a second housing. A plate-like lock arm is provided on the first housing and is inclinable like a seesaw. A lock hole penetrates a front end portion of the lock arm. A detector is mounted movably relative to the lock arm between a standby position and a detection position. The detector has a latch with a latching projection that engages the lock hole to hold the detector at the standby position before the housings are connected and to prevent the detector from moving toward the detection position. 
   A front end portion of the lock arm moves onto a lock projection of the second housing in the process of connecting the two housings and causes the lock arm to deform resiliently. At this time, the detector inclines together with the lock arm and the latching projection remains engaged with the lock hole. Therefore the detector remains prevented from moving toward the detection position. The lock arm resiliently restores when the housings reach a properly connected state. Thus, the lock projection engages the lock hole to lock the housings together. Additionally, the latching projection moves onto the lock projection and disengages from the lock hole so that the detector can move to the detection position. Accordingly, an operator can determine whether the two housings are connected properly based on whether the detector can move to the detection position. 
   The front portion of the lock arm has a relatively low rigidity due to the penetration of the lock hole. Thus, a strong pressing force on the detector toward the detecting position could deform the front portion of the lock arm, and such a deformation could disengage the lock hole from the latching projection. As a result, the detector may be moved inadvertently from the standby position to the detection position. 
   The invention was developed in view of the above situation, and an object thereof is to reliably hold a detector at a standby position. 
   SUMMARY OF THE INVENTION 
   The invention relates to a connector with a housing that is connectable with a mating housing. A lock arm is provided on the housing and is displaceable like a seesaw. A lock hole is formed in a front end portion of the lock arm. A detector is mounted to the lock arm for movement between a standby position and a detection position. A latching projection is formed on the detector and engages the lock hole to hold the detector at the standby position and to prevent the detector from moving forward to the detection position when the housing is not connected to the mating housing yet. The lock arm moves onto a lock projection of the mating housing and inclines resiliently in the process of connecting the housing to the mating housing. The detector is inclined together with the lock arm. The lock arm restores resiliently when the housing and the mating housing reach a properly connected state so that the lock hole engages the lock projection. As a result, the housing and the mating housing are locked together. Additionally, the latching projection moves onto the lock projection and is disengaged from the lock hole to permit the detector to move toward the detection position. An operator can detect whether the housing is connected properly to the mating housing based on whether the detector is permitted to move toward the detection position. One or more reinforcing ribs project from the lock arm and increase the rigidity of the lock arm. Thus, the front end portion of the lock arm will not deform sufficiently to disengage the lock hole from the latching projection even if the latching projection of the detector exerts a strong pressing force on the hole edge of the lock hole in a direction toward the detection position. 
   The one or more reinforcing ribs preferably extend from a position at or near the front end of the lock arm to a position behind an inclination supporting point of the lock arm and are arranged adjacent to the lock hole. 
   The lock arm preferably is formed with at least one connecting portion connecting at least two of the reinforcing ribs. The connecting portion increases the rigidity of the reinforcing ribs and further prevents the deformation of the front end portion of the lock arm. 
   The connecting portion preferably is a plate that is substantially parallel to a moving direction of the detector and that can slide in contact with the detector. Thus, the detector is guided by the connecting portion from the standby position to the detection position. 
   If the connecting portion was formed over an area corresponding to the resiliently deformable part of the detector, the connecting portion would need to be distanced from the detector to ensure a space for deformation of the detector. Thus, the connector would be enlarged. Accordingly, the connecting portion preferably is not in an area corresponding to a part of the detector that is resiliently deformable as the latching projection moves onto the lock. Therefore, the deformation space for the detector is ensured even if the connecting portion is near the detector. As a result, the connector can be miniaturized. 
   An operable portion preferably is formed near the rear end of the detector and projects more backward than the connecting portion. The operable portion can be operated to move the detector between the standby position and the detection position and to unlock the lock arm so that the lock hole is disengaged from the lock projection. Therefore, it is not necessary to form the lock arm with an operable portion and the shape of the lock arm can be simplified. 
   The invention also relates to a connector assembly comprising the above-described connector and a mating connector connectable therewith. The mating connector comprises a mating housing with a lock projection that interacts with the lock arm in a connection process. 
   These and other features and advantages of the invention will become more apparent upon reading the following detailed description and accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a front view of a first housing showing a state where a detector is mounted at a standby position in one embodiment. 
       FIG. 2  is a side view of the first housing showing the state where the detector is mounted at the detection position. 
       FIG. 3  is a plan view of the first housing showing the state where the detector is mounted at the detection position. 
       FIG. 4  is a section showing an intermediate state where two housings are connected properly and the detector is moving from the standby position to a detection position. 
       FIG. 5  is a section along X-X of  FIG. 1  showing a state where the detector is located at the standby position. 
       FIG. 6  is a section of the first housing showing a state reached by moving the detecting member to the detection position. 
       FIG. 7  is a front view of the first housing in a state where the detector is not mounted. 
       FIG. 8  is a rear view of the first housing in the state where the detector is not mounted. 
       FIG. 9  is a plan view of the first housing in the state where the detector is not mounted. 
       FIG. 10  is a front view of the detector. 
       FIG. 11  is a rear view of the detector. 
       FIG. 12  is a side view of the detector. 
       FIG. 13  is a plan view of the detector. 
       FIG. 14  is a bottom view of the detector. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A connector in accordance with the invention is described with reference to  FIGS. 1 to 14 . The connector of this embodiment has first and second housings  10  and  50  that are connectable with one another. Connecting ends of the housings  10 ,  50  are referred to as the front ends. 
   The first housing  10  is made unitarily e.g. of synthetic resin to include a terminal accommodating portion  11  and a tubular fitting  12 . The tubular fitting  12  surrounds the terminal accommodating portion  11  and a forwardly open connection space  13  is defined between the terminal accommodating portion  11  and the tubular fitting  12 . Female terminal fittings  14  are accommodated in the terminal accommodating portion  11 . 
   A lock arm  15  is formed unitarily on the upper surface of the terminal accommodating portion  11 . The lock arm  15  is long in forward and backward directions and hence is substantially parallel to connecting and separating directions CSD of the housings  10 ,  50 . Left and right legs  16  are formed at substantially longitudinal center positions of the lock arm  15  and join the lock arm  15  to the outer surface of the terminal accommodating portion  11 . The lock arm  15  includes two laterally symmetrical beams  17  that are long and narrow in forward and backward directions. A base plate  18  connects the beams  17  from positions adjacent to or slightly before the legs  16  to the rear ends. A lock  19  connects the front ends of the beams  17 , and the legs  16  project from the lower surfaces of the beams  17 . Guide ribs  20  project sideways from upper parts of the outer side surfaces of the beams  17  and extend straight substantially parallel with a moving direction MD of the detector  30 . 
   The lock arm  15  normally is kept in a locking posture in which the two beams  17  extend forward and backward in directions substantially parallel to connecting and separating directions CSD of the housings  10 ,  50 . However, the lock arm  15  is resiliently deformable like a seesaw to an unlocking posture in which the lock  19  at the front end is displaced up and away from the outer surface of the terminal accommodating portion  11  with the legs  16  as supports. The upper wall of the tubular fitting  12  has a cutout  21  to avoid the interference with the lock arm  15  when the lock arm  15  is deformed resiliently to the unlocking posture. 
   A substantially rectangular lock hole  22  penetrates the front end portion of the lock arm  15  from the upper surface to the lower surface at a position bounded by the beams  17 , the lock  19  and the front end edge of the base plate  18 . The lock hole  22  reduces the rigidity of the front end portion of the lock arm  15 . However, long narrow reinforcing ribs  23  project from the upper surfaces of the beams  17  for increasing the rigidity of at least the front end portion of the lock arm  15 . 
   The reinforcing ribs  23  extend from the front ends to the rear ends of the beams  17 . The reinforcing ribs  23  extend parallel to the connecting direction CD of the housings  10 ,  50  at positions on opposite sides of the lock hole  22 . Upper edges of the front end portions of the reinforcing ribs  23  incline down toward the front end of the housing  10 . The inclined portions extend from the front ends of the arms  17  to a substantially center position of the lock hole  22 . Further, the guide ribs  20  project laterally out from the reinforcing ribs  23 . 
   A connecting portion  24  unitarily connects the upper edges of the reinforcing ribs  23  from the rear ends of the reinforcing ribs  23  to a position slightly before the legs  16  and slightly behind the front edge of the lock hole  22 . Three laterally spaced restricting grooves  25  are formed on the lower surface of the connecting portion  24  and extend forward and backward along connecting and separating directions CSD from the front end to the rear end. A guide space  26  is enclosed by the base plate  18 , the reinforcing ribs  23  and the connecting portion  24 . The guide space  26  has open front and rear ends. 
   The connector also has a detector  30  that is made unitarily e.g. of synthetic resin. The detector  30  has two long narrow side frames  31  that extend in forward and backward directions and a substantially flat plate  32  that connects the upper edges of the side frames  31 . An operable portion  33  is continuous with rear ends of the side frames  31  and with the rear of the flat plate  32  and an extension  34  is cantilevered forward from the operable portion  33  between the side frames  31 . Guide grooves  35  extend forward and backward along the inner surfaces of the side frames  31 . The guide grooves  35  of the detector  30  slidably engage the guide ribs  20  of the lock arm  15 . Thus, the detector  30  is movable relative to the lock arm  15  along a moving direction MD between a standby position SP and a detection position DP that is more forward than the standby position SP. Both the flat plate  32  and the extension  34  are substantially parallel to the moving direction MD of the detector  30 . 
   A thick portion  36  is formed on the lower surface of the extension  34  from a position slightly behind the front end of the extension  34  to the rear end of the extension  34  at the front of the operable portion  33 . A high rigidity portion  37  is defined on the extension  34  at the thick portion  36  and regulates vertical deformations substantially parallel to resilient deforming directions of the lock arm  15 . A plate-like resilient piece  38  is defined at the front end of the extension  34  in an area from the front end of the high-rigidity portion  37  to the front end of the extension  34 . The vertical dimension of the resilient piece  38  is less than the vertical dimension of the high-rigidity portion  37 . A latch  39  projects down from the lower surface of this resilient piece  38  at a position slightly behind the front end. Further, three restricting ribs  40  extend in forward and backward directions along the upper surface of the extension  34 . 
   The resilient piece  38  is accommodated in the guide space  26  and the restricting ribs  40  engage the restricting grooves  25  when the detector  30  is at the standby position SP shown in  FIG. 5  to prevent lateral movements of the extension  34  relative to the lock arm  15 . The reinforcing ribs  23  also hold the extension  34  from the left and right sides to prevent lateral movements of the extension  34  relative to the lock arm  15 . Furthermore, the side frames  31  contact the outer side surfaces of the reinforcing ribs  23  to prevent lateral movements of the detector  30  relative to the lock arm  15 . 
   The extension  34  is held between the base plate  18  and the connecting portion  24  to prevent vertical movements of the extension  34  relative to the lock arm  15 . The front end of the connecting portion  24  is behind the rear end of the resilient piece  38  to avoid interference with the resilient piece  38  when the resilient piece  38  is deformed out or up. The lower surface of the flat plate  32  slides in contact with the upper surface of the connecting portion  24 . Thus, the extension  34  and the flat plate  32  vertically sandwich the connecting portion  24 . 
   The latch  39  of the resilient piece  38  enters the lock hole  22  from above and the front surface of the latch  39  engages the front end edge of the lock hole  22  (rear surface of the lock  19 ) from behind so that the latch projection  39  does not move further forward. This engagement holds the detector  30  at the standby position SP and prevents forward movement of the detector  30  to the detection position DP. The operable portion  33  projects back beyond the rear end of the lock arm  15  to enable a forward pushing operation, a backward pulling operation and a downward pressing operation. 
   The second housing  50  includes a terminal holding portion  51  and a receptacle  52  projects forward from the terminal holding portion  51 , as shown in  FIG. 4 . Male terminal fittings  53  are held in the terminal holding portion  51  so that tabs  54  at the leading ends of the male terminal fittings  53  project from the front surface of the terminal holding portion  51  and into the receptacle  52 . A lock  55  projects out from upper surface of the upper wall of the receptacle  52 . A guiding slant  56  is formed at the front of the lock  55  and is inclined with respect to the connecting direction CD of the housings  10 ,  50 . A locking surface  57  is formed at the rear of the lock  55  and is substantially normal to the connecting direction of the two housings  10 ,  50 . 
   Upon connecting the two housings  10 ,  50 , the detector  30  is held at the standby position SP and, in this state, the two housings  10 ,  50  are brought closer to each other to insert the receptacle  52  into the connection space  13 . As a result, the lock  19  at the front end of the lock arm  15  contacts and slides along the guiding slant  56  of the lock  55  of the second housing  50  so that the lock arm  15  deforms resiliently into the unlocking posture. The detector  30  also inclines with the lock arm  15  to displace the resilient piece  38  at the front end of the detector  30  out and up. In this partly connected state of the housings  10 ,  50 , the latch  39  remains engaged with the lock hole  22 . Thus, the detector  30  is held at the standby position SP and cannot move toward the detection position DP. 
   The lock  19  passes the lock projection  55  if the connecting operation proceeds sufficiently for the two housings  10 ,  50  to reach a properly connected state. Therefore the lock arm  15  restores resiliently toward the locking posture. The lock  19  engages the locking surface  57  of the lock projection  55  as the lock arm  15  resiliently restores so that the two housings  10 ,  50  are locked together in the properly connected state. 
   The lock  19  passes the lock projection  55  when the housings  10 ,  50  are locked in the properly connected state. Hence, the latch  39 , which had been engaged with the lock  19  from behind, moves onto the lock  55  to prevent an inward or downward displacement. Accordingly, the resilient piece  38  displaces out and up with respect to the lock  19  at the front end of the lock arm  15  and disengages from the lock  19  as the lock arm  15  resiliently restores. In this way, the latch  39  and the lock  19  disengage and the detector  30  can move forward in the moving direction MD to the detection position DP. 
   The operable portion  33  then is pushed from behind to move the detector  30  forward from the standby position SP to the detection position DP. The latch  39  moves from the upper surface of the lock  55  and slides along the upper surface of the lock  19  in the process of moving the detector  30  to the detection position DP, as shown in  FIG. 4 . 
   The latch  39  passes the lock  19  when the detector  30  reaches the detection position DP. Thus, the resilient piece  38  restores resiliently so that the latch  39  engages the lock  19  from the front. The operable portion  33  projects back from the rear of the lock arm  15  even with the detector  30  at the detection position DP. Thus, proper connection of the housings  10 ,  50  is detected based on whether the detector  30  can be moved to the detection position DP. 
   The resilient piece  38  is below the restriction  27  at the front part of the upper wall of the tubular fitting  12  when the detector  30  is at the detection position DP, and hence the resilient piece  38  cannot be deflected up and out. Accordingly, the lock arm  15  cannot deform resiliently with the detector  30  to the unlocking posture and the two housings  10 ,  50  are locked reliably together. 
   To separate the housings  10 ,  50 , the operable portion  33  is gripped to move the detector  30  from the detection position DP to the standby position SP. During this time, the resilient piece  38  deforms resiliently out and up so that the latch  39  moves onto the lock  19  and over to the upper surface of the lock  55 . Thus, the resilient piece  38  moves to a position distanced back from the restriction  27  and can be deflected out and up. 
   The operable portion  33  then is pressed down so that the lock arm  15  is deformed to the unlocking posture together with the detector  30 . This deformation of the lock arm  15  displaces the lock  19  up sufficiently to disengage from the lock  55  and to cancel the locking between the lock hole  22  and the lock  55 . The two housings  10 ,  50  then may be pulled apart while keeping the lock arm  15  in the unlocking posture. The lock  19  is displaced up as the lock arm  15  resiliently deforms to the unlocking posture. Thus, the lock  19  engages the latch  39  from the front when the resilient piece  38  resiliently restores. This engagement action locks the detector  30  at the standby position SP. It is sufficient to resiliently restore the lock arm  15  to the locking posture after the two housings  10 ,  50  are separated. During this time, the detector  30  is kept at the standby position SP since the latch  39  remains engaged with the lock  19 . 
   As described above, the reinforcing ribs  23  project from the lock arm  15  at opposite widthwise sides of the lock hole  22  and extend substantially from the front end of the lock arm  15  to positions behind the legs  16  that support the lock arm  15 . The reinforcing ribs  23  increase rigidity of the front portion of the lock arm  15 . Therefore, the front portion of the lock arm  15  will not deform to disengage the lock hole  22  from the latch  39  of the detector  30  even if the latch  39  exerts a strong pressing force on the edge of the lock hole  22  in a direction toward the detection position DP while the housings  10 ,  50  are separated. Accordingly, the detector  30  is held reliably at the standby position SP. 
   The lock arm  15  also has the connecting portion  24  that connects the reinforcing ribs  23 . The connecting portion  24  further increases the rigidity of the reinforcing ribs  23  and makes the front portion of the lock arm  15  even less likely to deform. 
   The connecting portion  24  is a plate and is aligned parallel to the moving direction MD of the detector  30 . The upper surface of the extension  34  of the detector  30  and the lower surface of the flat plate  32  of the detector  30  are held substantially in sliding contact with the connecting portion  24  when the detector  30  moves between the standby position SP and the detection position DP. Therefore, the detector  30  is guided by the connecting portion  24 . 
   If the connecting portion  24  was formed over an area corresponding to a resiliently deformable part of the detector  30 , the connecting portion  24  would have to be spaced from the detector  30  to define a space for permitting resilient deformation of the detector  30 . Therefore, the height of the connector would have to increase. However, the connecting portion  24  is not in an area corresponding to the resilient piece  38  of the detector  30 . Thus, a deformation space for the resilient piece  38  is ensured even if the connecting portion  24  is brought closer to the detector  30 , and the connector can be miniaturized. 
   The operable portion  33  is formed at the rear end of the detector  30  and projects more backward than the connecting portion  24  at all positions in a movable range between the standby position SP and the detection position DP. Thus, an operator merely needs to operate the operable portion  33  to disengage the lock hole  22  from the lock projection  55  and to move the detector  30  between the standby position SP and the detection position DP. Accordingly, it is not necessary to form the lock arm  15  with a separate operable portion and the shape of the lock arm  15  is simplified. 
   The 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. 
   Although the connecting portion is plate-like in the above embodiment, it may be a beam crossing between the pair of reinforcing ribs. In this case, one or more connecting portions may be provided. 
   The formation area of the connecting portion may be formed over the area corresponding to the part of the detector that is resiliently deformed as the latching projection moves onto the lock projection. 
   The reinforcing ribs are connected by the connecting portion in the above embodiment. However, the reinforcing ribs may not be connected by the connecting portion. 
   The lock arm may be provided with a special operable portion in addition to the operable portion of the detector. 
   The lock hole  22  is described as being a through-hole fully penetrating the lock arm  15  in the above embodiment. However, the lock hole may be a recess that does not fully penetrate the lock arm  15 .