Patent Publication Number: US-7214078-B2

Title: Connector and connector assembly

Description:
This application is a divisional of U.S. patent application Ser. No. 11/258,351, filed Oct. 24, 2005. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The invention relates to a connector with a movable member to facilitate connection with a mating connector. 
   2. Description of the Related Art 
   U.S. Pat. No. 5,611,703 discloses a connector with a lever mounted on a first housing. The lever can be held temporarily at a standby position so that cam followers of a second housing can enter cam grooves of the lever. The housings are connected by displacing the lever to a connection position. The connector includes means for temporarily holding the lever at the standby position, a return preventing means for preventing the lever from returning from the standby position to the mount position, and a locking means for locking the lever at the connection position. 
   The means for preventing the lever from returning from the standby position to the mount position and the locking means for locking the lever at the connection position are provided separately on the prior art lever-type connector. Thus, the housings and the lever have complicated shapes. 
   Lever-type connectors generally have a substantially U-shaped lever with two arms that mount to the housing and a connecting portion that extends between the arms. Operational efficiency can be improved by enlarging an operable portion of the lever taking in the thickness of the housing. However, this enlarges the entire lever-type connector. 
   Some lever-type connectors have been miniaturized by providing a substantially plate-shaped lever that extends only along an upper surface of the first housing. The plate-shaped lever then can be displaced along the upper surface of the first housing. However, the operable portion of the plate-shaped lever must be made thicker because it is difficult to manipulate an operable portion that is as thin as the remainder of the plate-shaped lever. 
   In the lever-type connector in which the plate-shaped lever is placed on the upper surface of the housing, the depth and width of the lever-type connector become smaller as the overlapping area of the lever and the housing increases. However, if the thicker operable portion is placed on the upper surface of the housing, the height of the lever-type connector increases. 
   The present invention was developed in view of the above problem and an object thereof is to simplify the shape of a connector and/or to miniaturize it. 
   SUMMARY OF THE INVENTION 
   The invention relates to a connector with a housing and a movable member mountable on the housing. The movable member is configured to display a cam action together with cam follower of a mating housing. More particularly, the cam follower can enter a cam groove of the movable member after the movable member is displaced from a mount position to a standby position. The housing then can be connected with the mating housing by displacing the movable member from the standby position to a connection position. A return preventing means is provided for preventing the movable member from returning from the standby position towards the mount position, and a locking means is provided for holding the movable member substantially at the connection position. The return preventing means is on one of the housing and the movable member is engageable with the locking means on the other of the housing and the movable member. Thus, it is not necessary to provide the one member with a locking means for exclusive use in addition to the return preventing means. Accordingly, the shape of the connector can be simplified. 
   The return preventing means preferably comprises a flexible locking piece that can be deformed resiliently to disengage from the locking means. 
   The mating housing preferably is disposed to contact the flexible locking finger or other such return preventing means when the housing is connected with the mating housing. The contact between the mating housing and flexible locking piece preferably prevents the flexible locking piece from displacing in a direction to disengage from the locking means. Thus, a reliable locking function is achieved. 
   The connector may further comprise a connection preventing means, such as a resiliently deformable resilient locking piece, to prevent a displacement of the movable member from the standby position to the connection position. 
   The resilient locking piece preferably can be deformed resiliently by a canceling portion of the mating housing to cancel the displacement prevented state of the movable member by the resilient locking piece as the cam follower enters the cam groove. 
   The movable member preferably is substantially plate-shaped. 
   The housing preferably has a terminal accommodating portion for accommodating at least one terminal fitting and a substantially tubular sealing tower for accommodating a resilient plug mounted on the rear of the terminal fitting. The sealing tower is shorter than the terminal accommodating portion. The movable member is substantially plate-shaped and extends substantially along only one surface of the housing, and has an operable portion. The sealing tower is shifted from the terminal accommodating portion so that the center of axis thereof is offset from the middle of the terminal accommodating portion. The operable portion is accommodated in an accommodation space defined substantially adjacent the sealing tower by an offset between the respective surfaces of the terminal accommodating portion and the sealing tower. 
   The operable portion preferably is thicker than other parts and shaped to be placed on the respective surface of the housing in the process of displacing the movable member. 
   The thickness of an upper end area of the sealing tower facing the accommodation space preferably is thinner than other areas. Thus, the position of the operable portion can be lowered to realize a further reduction in the height of the entire lever-type connector. 
   The operable portion preferably is substantially flush with or inward of the outer surface of the housing when the movable member is at the connection position. Thus, external matter is not likely to interfere with the operable portion from below and will not detach the lever from the housing. 
   The invention also relates to a connector assembly comprising the above-described connector and a mating connector connectable therewith. 
   These and other features of the invention will be more apparent upon reading the following detailed description of preferred embodiments and accompanying drawings. Even though embodiments are described separately, features thereof may be combined to additional embodiments. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a plan view of a first housing with a lever at a mount position. 
       FIG. 2  is a plan view of the first housing with the lever at a standby position. 
       FIG. 3  is a plan view of the first housing showing the lever at a connection position. 
       FIG. 4  is a plan view showing a cam follower at the entrance of a cam groove. 
       FIG. 5  is a plan view showing the two housings connected. 
       FIG. 6  is a rear view of the first housing with the lever at the mount position. 
       FIG. 7  is a rear view of the first housing showing the state where the lever is at the standby position. 
       FIG. 8  is a rear view of the first housing showing the state where the lever is at the connection position. 
       FIG. 9  is a plan view of the first housing. 
       FIG. 10  is a front view of the first housing. 
       FIG. 11  is a rear view of the first housing. 
       FIG. 12  is a section along  12 — 12  of  FIG. 9 . 
       FIG. 13  is a section along  13 — 13  of  FIG. 9 . 
       FIG. 14  is a plan view of the lever. 
       FIG. 15  is a front view of the lever. 
       FIG. 16  is a rear view of the lever. 
       FIG. 17  is a bottom view of the lever. 
       FIG. 18(   a ) is a section along  18   a — 18   a  of  FIG. 2  and  FIG. 18(   b ) is a section along  18   b — 18   b  of  FIG. 4 . 
       FIG. 19(   a ) is a section showing a state where a flexible locking piece is deformed in the process of displacing the lever from the mount position to the standby position and  FIG. 19(   b ) is a section along E—E of  FIG. 2 . 
       FIG. 20  is a section along  20 — 20  of  FIG. 5 . 
       FIG. 21  is a section along  21 — 21  of  FIG. 5 . 
       FIG. 22  is a section along  22 — 22  of  FIG. 3 . 
       FIG. 23  is a plan view of a second housing. 
       FIG. 24  is a front view of the second housing. 
       FIG. 25  is a section along  25 — 25  of  FIG. 23 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A connector according to the invention is described with reference to  FIGS. 1 to 25 . The connector has a first housing  10  and a second housing  60  that can be connected with and separated from each other by a movable member. Ends of the housings  10 / 60  to be connected with the other are referred to as the front. 
   The first housing  10  is made e.g. of a synthetic resin and is a flat generally rectangular block that is a shorter along a height direction HD than along forward and backward directions FBD and transverse direction TD. The first housing  10  has a terminal accommodating portion  11  and a seal tower  25 . 
   The terminal accommodating portion  11  has a wide rectangular main portion  12  and a tubular fitting  13  that surrounds the main portion  12 . A forwardly open fitting recess  14  is formed between the outer periphery of the main portion  12  and the inner periphery of the tubular fitting  13 . Cavities  15  are formed in a substantially transverse row in the main portion  12 . 
   An upper wall  13 W of the tubular fitting  13  has a substantially rectangular notch  16  that extends back from a middle part of the front edge. A substantially rectangular receiving portion  18  projects at the rear right corner of the notch  16  and is continuous with the right surface of the notch  16  via quarter-circular arc. A center pedestal  17 C is formed behind the notch  16  at the front end of the upper surface of the seal tower  25  at substantially the same height as and substantially flush with the upper wall  13 W of the tubular fitting  13 . Similarly, left and right pedestals  17 L and  17 R are formed at the opposite left and right sides of the center pedestal  17 C at the front end of the upper surface of the seal tower  25 . The left and right pedestals  17 L and  17 R are at substantially the same height as and substantially flush with the upper wall  13 W of the tubular fitting  13 . Rear ends of the center and left pedestals  17 C and  17 L are at substantially the same position. The rear end of the right pedestal  17 R is behind the rear ends of the center and left pedestals  17 C and  17 L, i.e. at substantially the same position as the rear end of the seal tower  25 . 
   A substantially cylindrical support shaft  19  projects substantially in the vertical direction VD from the upper surface of the center pedestal  17 C. Retaining projections  19   a  project transversely from the upper end of the support shaft  19 . A flexible locking piece  20  is formed between the center and left pedestals  17 C and  17 L and at the left side of the support shaft  19 . The flexible locking piece  20  cantilevers back along the forward and backward directions FBD from the rear end of the upper wall  13 W of the tubular fitting  13  and is resiliently deformable to incline up and down with the front end as a support. A lock projection  20   a  is formed on the upper surface of the rear end of the flexible locking piece  20 . On the other hand, an escaping recess  21  is formed in the upper surface of the upper wall  13 W of the tubular fitting  13  between the center and right pedestals  17 C and  17 R and at the right side of the support shaft  19 . The escaping recess  21  communicates with the fitting recess  14  and with the accommodation space  26 . The escaping recess  21 , the support shaft  19  and the flexible locking piece  20  are arranged substantially transversely along a direction substantially normal to the connecting direction CD of the two housings  10 ,  60 . 
   Left and right plate-shaped pressing portions  22 R,  22 L are provided above the upper wall  13 W of the tubular fitting  13 . The pressing portions  22 R,  22 L are substantially parallel with the upper wall  13 W of the tubular fitting  13 . 
   The right pressing portion  22 R is narrow and long along forward and backward directions FBD, and extends from the right edge of the notch  16  to the right edge of the tubular fitting  13 . The right pressing portion  22 R is continuous with the upper wall  13 W of the tubular fitting  13  at its front and right edges. Additionally, the right pressing portion  22 R spans an area extending from the front end of the tubular fitting  13  to a position slightly before the rear end of the right pedestal  17 R. The left side of the right pressing portion  22 R has an arcuate edge  22 Ra and a substantially straight edge  22 Rb. The arcuate edge  22 Ra is substantially concentric with the support shaft  19 . The straight edge  22 Rb is smoothly continuous with the arcuate edge  22 Ra and extends substantially along forward and backward directions FBD to the rear end. 
   The left pressing portion  22 L is narrow and long along forward and backward directions FBD, but is slightly wider than the right pressing portion  22 R. The left pressing portion  22 L is in an area extending from the left edge of the notch  16  to the left edge of the tubular fitting  13 , and is continuous with the upper wall  13 W of the tubular fitting  13  at its front and left edges. The left pressing portion  22 L extends from the front end of the tubular fitting  13  to the rear end of the left pedestal  17 L. An arcuate edge  22 La and a substantially straight edge  22 Lb extend along the right edge of the left pressing portion  22 L. The arcuate edge  22 La is substantially concentric with the support shaft  19 . The substantially straight edge  22 Lb is smoothly continuous with the arcuate edge  22 La and extends along forward and backward directions FBD to the rear end. The arcuate edge portion  22 La is formed with two recesses  23 . 
   A right guide groove  24 R is formed between the right pressing portion  22 R and the upper wall  13 W of the tubular fitting  13 . The right guide groove  24 R is open at the left and rear sides and extends towards the support shaft  19 . On the other hand, a left guide groove  24 L is formed between the left pressing portion  22 L and the upper wall  13 W of the tubular fitting  13 . The left guide groove  24 L is open at the right and rear sides and extends towards the support shaft  19 . 
   The seal tower  25  extends back from the rear end of the terminal accommodating portion  11 , and is shorter than the terminal accommodating portion  11  and the tubular fitting  13 . The seal tower  25  has three cylinders  25   a  arranged transversely at the substantially same height as and in conformity with the respective cavities  15 . The height of the centers of the axes of the respective cylinders  25   a  along the height direction HD is lower than the center position of the terminal accommodating portion  11  and the tubular fitting  13  with respect to the height direction HD. By shifting the seal tower  25  down relative to the terminal accommodating portion  11 , the bottom end of the seal tower  25  is substantially at the same height as the bottom surface of the terminal accommodating portion  11  and the upper end of the seal tower  25  is lower than the upper surfaces of the terminal accommodating portion  11  and the tubular fitting  13 . The height difference between the terminal accommodating portion  11  and the seal tower  25  forms the accommodation space  26  that is open at the upper, left, right and rear sides above the seal tower  25 . 
   Each female terminal fitting  30  is narrow and long in forward and backward directions FBD. A substantially rectangular tube  31  is formed at the front of each female terminal fitting  30  and a wire connecting portion  32  is formed at the rear. The wire connecting portion  32  is an open barrel configured for crimped, bent or folded connection with a wire  33  and the front end of a tubular resilient rubber plug  34  that is fit hermetically on the wire  33 . The female terminal fitting  30  is inserted into the cavity  15  from behind and is secured by a lock  15   a . A large diameter portion  34   a  of the resilient plug  34  is formed behind the wire connecting portion  32  and is held hermetically in contact with the inner peripheral surface of the seal tower  25 . A retainer  35  is mounted on the main portion  12  of the first housing  10  from the front, and a resilient rubber seal ring  36  is mounted on the rear end of the outer peripheral surface of the main portion  12 . The retainer  35  prevents the seal ring  36  from coming off forward. 
   The lever  40  is made e.g. of a synthetic resin, and is substantially plate-shaped. The forward and backward directions FBD and the transverse direction TD of the lever  40  refer to a state where the lever  40  is held on the first housing  10  at the connection position CP where the housings  10 ,  60  are substantially connected. 
   The lever  40  includes main body  41  that is substantially circular in plan view, but has a comb-shaped notch in a rear of a substantially circular peripheral area. A substantially round bearing hole  42  vertically penetrates a substantially center of the main body  41 , and left and right arcuate retaining edges  42   a  bulge in from the inner circumferential edge of the bearing hole  42 . A cam groove  43  is formed before the bearing hole  42  of the main body  41  and is aligned oblique to both the circumferential and radial directions. An entrance  43   a  of the cam groove  43  opens at the outer peripheral edge of the main body  41  at a position slightly shifted to the right from the front end. 
   An operable portion  44  is formed at the left-half area of the rear end of the main body  41 . The operable portion  44  has a support  45  that bulges down from the rear edge of the main body  41 . Left and right finger placing portions  46 L,  46 R project up from the left and right ends of the support  45  to a position above the main body  41 . The operable portion  44  also has a lock arm  47 . 
   The lock arm  47  is a plate with substantially the same thickness as the lever main body  41  and is located at substantially the substantially same height as the lever main body  41 . The lock arm  47  is substantially rectangular in plan view and is long along forward and backward directions FBD. A leg  48  supports the lock arm  47  on the upper surface of the support  45  at a position slightly before the rear end of the lock arm  47 . Thus, the lock arm  47  can undergo a seesaw-like resilient displacement to take a forward inclined posture or a backward inclined posture with the leg  48  as a support. A substantially rectangular lock hole  49  penetrates the front end of the lock arm  47 , and a finger contact  50  is at the rear end of the lock arm  47 . The lock arm  47  is above the support  45  and between the finger placing portions  46 L,  46 R. 
   Left and right bulges  51 L,  51 R bulge radially out substantially concentrically with the main body  41  from an area of the main body  41  except the rear edge. The bulges  51 L,  51 R are about half as thick as the main body  41 , and the lower surfaces of the bulges  51 L,  51 R are continuous with and substantially flush with the lower surface of the main body  41 . Accordingly, the upper surfaces of the bulges  51 L,  51 R are lower than the upper surface of the main body  41  to define steps. The left bulge  51 L extends from the left finger placing portion  46 L to the front end of the main body  41 , and the front edge of the left bulge  51 L extends substantially straight along the transverse direction TD to be substantially tangent to the outer circumference of the main body  41 . On the other hand, the right bulge  51 R extends from the rear end of the main body  41  to a position slightly before the bearing hole  42  and behind the front end of the main body  41 . A dimension of the right bulge  51 R along forward and backward directions FBD is approximately equal to the width of the notch  16  of the first housing  10 . Two guide projections  55  are formed on the outer peripheral edge of the main body  41  before the right bulge  51 R and project radially out from the opposite sides of the entrance  43   a  of the cam groove  43 . The guide projections  55  have the substantially same thickness as the bulges  51 L,  51 R and are substantially continuous with and substantially flush with the lower surface of the main body  41 . 
   A return preventing portion  52  is formed on the main body  41  before the lock arm  47 . The return preventing portion  52  substantially vertically penetrates the lever main body  41  and is long and narrow substantially along a radial direction centered on the bearing hole  42 . A distance of the return preventing portion  52  from the bearing hole  42  is substantially equal to a distance from the support shaft  19  to the lock hole  49 . A substantially arcuate escaping groove  53  is formed in the lower surface of the main body  41  and extends from the return preventing portion  52  to the lock arm  47 . 
   A long narrow resilient locking piece  54  is formed at the right side of the bearing hole  42  in the main body  41 . The resilient locking piece  54  is cantilevered rearwardly on the main body  41  and a rear portion of the resilient locking piece  54  is resiliently displaceable substantially up and down with the front end as a support. A rear portion of the resilient locking piece  54  projects below the main body  41 . 
   The second housing  60  is made e.g. of a synthetic resin and is an integral or unitary assembly of a wide block-shaped main body  61  and a substantially rectangular tubular receptacle  62  that projects forward from the main body  61 . Male terminal fittings  63  are inserted into the housing main body  61  from behind to be locked by respective locking portions, and tabs  63   a  at the front ends of the male terminal fittings  63  project forward in the receptacle  62 . A cam follower  64  is formed on the outer surface of the upper wall of the receptacle  62  substantially in the widthwise center and near the front end of the receptacle  62 . The cam follower  64  is substantially round and projects out with its center axis oriented substantially in a vertical direction VD. Left and right canceling ribs  65  project up from the outer surface of the upper wall of the receptacle  62  at the opposite left and right sides of the cam follower  64 . The left and right canceling ribs  65  extend substantially straight along forward and backward directions FBD and parallel to the connecting direction CD with the first housing  10 . 
   The lever  40  is aligned to the first housing  10  so that the right bulge  51 R is at the front end. The lever  40  then is brought closer to the first housing  10  from above. Then, as shown in  FIG. 1 , the lever main body  41  is fit into a space between the left and right pressing portions  22 R,  22 L and the right bulge  51 R is fit into the notch  16 . Additionally, the guide projections  55  are fit into the recesses  23  and the bearing hole  42  is engaged with the support shaft  19  by passing the retaining projections  19   a  of the support shaft  19  through clearances between the retaining edges  42   a  of the bearing hole  42 . The resulting position is the mount position MP of the lever  40 . In this state, the flexible locking piece  20  is deformed resiliently down by the lower surface of the main body  41 , and a substantially right half of the operable portion  44  is in the accommodation space  26 , whereas a substantially left half of the operable portion  44  projects back from the rear end of the first housing  10 . The lever main body  41  is placed on the outer surfaces of the upper wall  13 W of the tubular fitting  13 , the first left pedestal  17 L, and the center pedestal  17 C, but is not placed on the upper surface of the right pedestal  17 R. 
   In this state, the left finger portion  46  of the operable portion  44  can be pushed to the left e.g. by a finger. Thus, the lever  40  is rotated clockwise by about 45° around the support shaft  19  to the standby position SP. In the process of rotation, the outer circumferential surface of the main body  41  slides substantially along the left and right arcuate edges  22 La,  22 Ra. The main body  41  is placed on the outer surfaces of the upper wall  13 W of the tubular fitting  13 , the left pedestal  17 L and the center pedestal  17 C, and also on the upper surface of the right pedestal  17 R. Additionally, the flexible locking piece  20  slides substantially in contact with the lower surface of the main body  41  while being resiliently deformed down, as shown in  FIG. 19(   a ). When the lever  40  reaches the standby position SP, the return preventing portion  52  of the lever  40  engages the lock projection  20   a  of the resiliently restored flexible locking piece  20  in the counterclockwise returning direction, as, shown in  FIGS. 2 and 19(B) , and the lever  40  at the standby position SP is prevented from returning counterclockwise toward the mount position MP relative to the first housing  10 . At the standby position SP, the extending end of the resilient locking piece  54  engages the receiving portion  18  of the first housing  10  in the clockwise direction, as shown in  FIGS. 2 and 18(   a ), to prevent the lever  40  at the standby position SP from rotating clockwise towards the connection position CP relative to the first housing  10 . In this way, the lever  40  is held at the standby position SP and is prevented from rotating in both forward and reverse directions. 
   With the lever  40  at the standby position SP, a front part of the operable portion  44  is in the accommodation space  26  and a rear part of the operable portion  44  projects back from the rear end surface of the first housing  10 , as shown in  FIG. 2 . Further, the retaining edges  42   a  of the bearing hole  42  engage the retaining projections  19   a  of the support shaft  19  from below, and the right and left bulges  51 R,  51 L fit respectively into the right and left guide grooves  24 R,  24 L. Thus, the pressing portions  22 R,  22 L engage the upper surfaces of the bulges  51 R,  51 L. Upward displacement of the lever  40  relative to the first housing  10  along the axis of rotation of the lever  40  is prevented by these engagements. Further, there comes a state where the entrance  43   a  of the cam groove  43  faces forward towards the notch  16  so that the cam follower  64  can enter the cam groove  43  from the front. 
   The second housing  60  can be connected with the first housing  1 . 0  from the front when the lever  40  is in the standby position SP. More particularly, the receptacle  62  is fit lightly into the fitting recess  14 . The cam follower  64  then passes a clearance between the guide projections  55  to enter the entrance  43   a  of the cam groove  43  as shown in  FIG. 4 , and the canceling ribs  65  having entered the notch  16  contact the lower surface of the resilient locking piece  54  to displace the resilient locking piece  54  up and out, as shown in  FIG. 18(   b ). The interlocked state of the resiliently locking piece  54  and the receiving portion  18 , i.e. the state preventing the rotation of the lever  40  from the standby position SP to the connection position CP is canceled by the displacement of the resilient locking piece  54 . 
   The left finger placing portion  46 L of the operable portion  44  can be pushed obliquely forward to the left e.g. by a finger. Thus, the lever  40  is displaced in the engagement direction to the connection position CP by rotating the operable portion  44  clockwise by about 45° about the support shaft  19 . The second housing  60  is pulled into the first housing  10  by a cam action (force multiplying action) caused by the engagement of the cam groove  43  and the cam follower  64  as the lever  40  is rotated. The housings  10 ,  60  reach a properly connected state when the lever  40  reaches the connection position and the tabs  63   a  enters the rectangular tubes  31  to connect the male terminal fittings  63  and the female terminal fittings  30  electrically. Thus, the operation of the lever  40  connects the two housings  10 ,  60 . 
   In the process of rotating the lever  40 , the resilient locking piece  54  is displaced obliquely back to the right in sliding contact with the upper surfaces of the canceling portions  65  and the receiving portion  18  while being resiliently displaced up and out. The resilient locking piece  54  is restored resiliently to enter the escaping recess  21  when the lever  40  reaches the connection position CP, as shown in  FIG. 20 . Further, the right bulge  51 R is kept in the right guide groove  24 R and the right guide projection  55  is fit in the right guide groove  24 R. The left bulge  51 L is kept in the left guide groove  24 L. In this way, the peripheral edge of the lever  40  is prevented from separating up from the first housing  10  so that the lever  40  can be operated stably. 
   In the process of rotating the lever  40  to the connection position CP, the lock projection  20   a  moves towards the lock arm  47  in the escaping groove  53  while the flexible locking piece  20  undergoes no resilient displacement. The lock projection  20   a  and the front end of the lock arm  47  interfere with each other immediately before the lever  40  reaches the connection position CP. At this time, a downward or outward resilient displacement of the flexible locking piece  20  is prevented because the front end of the upper wall of the receptacle  62  that is fit into the fitting recess  14  contacts the flexible locking piece  20  from below. Accordingly, the front end of the lock arm  47  moves over the lock projection  20   a  while the lock arm  47  is resiliently displaced up. 
   The flexible locking piece  20  and the lock arm  47  deform resiliently to engage the lock projection  20   a  with the lock hole  49  when the lever  40  reaches the connection position CP, as shown in  FIGS. 3 and 21 . At this time, the edge of the lock hole  49  contacts the lock projection  20   a  in the counterclockwise direction to prevent the lever  40  at the connection position CP from returning back to the standby position SP. At this time, the lock projection  20   a  and the lock hole  49  are not disengaged inadvertently from each other since the flexible locking piece  20  is prevented from a downward resilient displacement by the contact of the receptacle  62  from below. Further, the left finger placing portion  46 L and the corresponding left end of the support  45  engages the rear end surface of the left pedestal  17 L in the clockwise direction. In this way, the lever  40  is locked at the connection position CP and is prevented from rotating in both forward and reverse directions. Similarly, with the lever  40  at the connection position CP, substantially the entire operable portion  44  is in the accommodation space  26  and the rear end surface of the operable portion  44  (supporting portion  45  and left and right finger placing portions  46 L,  46 R) is substantially flush with the rear end surface of the sealing tower  25  of the first housing  10 . 
   To separate the two connected housings  10 ,  60 , the finger contact portion  50  of the lock arm  47  is pressed down and in by a finger from outside or above. Thus, the lock arm  47  is displaced resiliently in a seesaw manner resiliently to disengage the lock hole  49  from the lock projection  20   a , as shown in phantom in  FIG. 21 . Thus, the lever  40  is permitted to rotate in the returning direction and to the standby position SP. The cam action caused by the engagement of the cam follower  64  and the cam groove  43  pushes the second housing  60  forward relative to the first housing  10  as the lever  40  rotates. As a result, the two housings  10 ,  60  are separated. 
   As described above, since the flexible locking piece  20  on the first housing  10  is engageable with the lock arm  47  of the lever  40  to lock the lever  40  at the connection position CP. Thus, it is not necessary to provide the first housing  10  with a locking means for exclusive use in addition to the flexible locking piece  20 . Accordingly, the shape of the first housing  10  can be simplified as compared to a case where the first housing is provided with both the return preventing means for exclusive use and the locking means for exclusive use. 
   The second housing  60  contacts the flexible locking piece  20  to prevent disengagement of the flexible locking piece  20  from the lock  47  when the housings  10 ,  60  are connected. Therefore, secure locking is achieved by the engagement of the flexible locking piece  20  and the lock arm  47 . 
   The flexible locking piece  20  passes the return preventing portion  52  and deforms resiliently in the process of displacing the lever  40  from the mount position MP to the standby position SP. The flexible locking piece  20  restores resiliently and engages the return preventing portion  52  when the lever  40  reaches the standby position SP, thereby preventing the lever  40  from returning in the release direction from the standby position SP to the mount position MP. The first housing  10  and the lever  40  need not be relatively displaced to separate from each other in the process of displacing the lever  40  to the standby position SP, and hence connected portions of the first housing  10  and the lever  40  will not be wrenched due to relative displacements of the first housing  10  and the lever  40  in separating directions. 
   A U-shaped lever holds the housing between two opposed arms that are supported on the housing by shafts. The lever is mounted on the housing by widening the spacing between the arms for mounting onto the shafts. Thus, assembling operability is poor. Contrary to this, the lever  40  is substantially plate-shaped and extends along only one outer surface of the first housing. Thus, there is no need to resiliently deform the lever  40  for mounting and assembling operability is better. 
   In the process of causing the cam follower  64  to enter the cam groove  43 , the canceling portions  65  of the second housing  60  resiliently deform the resilient locking piece  54  of the connection preventing means. Thus, the lever  40  can move to the connection position CP. It is otherwise impossible to cancel the prevented state by the connection preventing means, resulting in better operability. 
   In the process of displacing the lever  40 , the bulges  51 L,  51 R fit into the guide grooves  24 L,  24 R to prevent the lever  40  from being displaced in separating direction from the first housing  10 . Thus, the displacement of the lever  40  can be stabilized. 
   The lock arm  47  and the flexible locking piece  20  are provided near the engaged portion of the left bulge  51 L and the left guide groove  24 L. Thus, relative displacements of the lever  40  and the first housing  10  in separating directions are prevented securely by the engagement of the left bulge  51 L and the left guide groove  24 L near the lock arm  47  and the flexible locking piece  20 . Therefore, the lock arm  47  and the flexible locking piece  20  are engaged stably and the lever  40  can be locked securely at the connection position CP. 
   The housing includes the terminal accommodating portion  11  and the sealing tower  25  that is shorter than the terminal accommodating portion  11 . The sealing tower  25  is shifted down towards the side opposite the side that has the lever  40  to define the accommodation space  26  above the sealing tower  25 . The thick operable portion  44  is accommodated in the accommodation space  26 . With this construction, a larger height can be ensured for the accommodation space  26  as compared to a case where the sealing tower is at the same height as the terminal accommodating portion, and the height of the entire lever-type connector can be reduced by locating the upper surface of the operable portion  44  at a lower or inward position. 
   Further, the upper end area of the sealing tower  25  that faces the accommodation space  26  is thinner than the other areas. Thus, the position of the operable portion  44  can be lowered to realize the further reduction in the height of the entire lever-type connector. 
   With the lever  40  held at the connection position CP, the operable portion  44  is accommodated in the accommodation space  26  and the rear end surface of the operable portion  44  is substantially flush with the rear end surface of the first housing  10 . Thus, there is no likelihood that external matter will interfere with the operable portion  44  e.g. from below and interference of external matter with the operable portion  44  cannot detach the lever  40  from the first housing  10 . 
   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 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 lever is substantially plate-shaped and rotatable along one surface of the housing in the foregoing embodiment. However, the lever may be substantially U-shaped and rotatable along both surfaces of the housing. 
   The two housings are connected while the lever is rotated in the foregoing embodiment. However, the invention is also applicable to connectors in which two housings are connected while a movable member is moved linearly or along another path such as an elliptic, arcuate, polygonal path. 
   The housing has the flexible locking piece to prevent displacement of the lever from the standby position to the mount position in the foregoing embodiment. However, the lever may have the flexible locking piece. 
   The lever has the resilient locking piece to prevent displacement of the lever from the standby position to the connection position in the foregoing embodiment. However, the housing may have the resilient locking piece. 
   The locked state of the resilient locking piece for preventing displacement of the lever from the standby position to the connection position is canceled as the male housing is fit initially in the foregoing embodiment. However, the locked state of the resilient locking piece may be canceled separately from the initial fitting operation of the male housing. 
   The receptacle of the male housing prevents the flexible locking piece from displacing in a direction to disengage from the lock arm when the two housings are connected in the foregoing embodiment. However, the displacement of the flexible locking piece from the lock arm may be permitted when the two housings are connected. 
   Pressing portions of the housing press the bulges on the lever in the foregoing embodiment to prevent displacement of the lever from the housing in a separating direction. However, the lever need not have the bulges. 
   The center of axis of the sealing tower is shifted from the middle position of the housing with respect to thickness direction in the foregoing embodiment. However, it may be at the substantially same position as the middle of the housing with respect to thickness direction. 
   The means for preventing displacement of the lever from the standby position to the mount position is resiliently deformable in the foregoing embodiment. However, it may be a projection projecting from the housing or the lever that is not resiliently deformable according to the invention. 
   The means for preventing displacement of the lever from the connection position to the standby position is resiliently deformable in the foregoing embodiment. However, it may be a projection projecting from the housing or the lever that is not resiliently deformable. 
   The means for preventing the displacement of the lever from the standby position to the connection position is resiliently deformable in the foregoing embodiment. However, it may be a projection projecting from the housing or the lever that is not resiliently deformable. 
   The thickness of the wall of the sealing tower at the side where the lever is arranged is thinner than the wall at the side opposite the lever in the foregoing embodiment. However, this thickness may be substantially equal to or larger than the thickness of the wall at the side opposite the lever. 
   The rear end of the operable portion of the lever is substantially flush with the rear end of the housing when the two housings are connected in the foregoing embodiment. However, it may be before or behind the rear end surface of the housing. 
   The above-described means for preventing the lever from returning from the standby position to the mount position is the flexible locking piece, which is resiliently deformable, and the return preventing portion, which is not resiliently deformable. However, the return preventing portion may be resiliently deformable similar to the flexible locking piece. 
   Although the return preventing portion of the first housing is engaged with the locking means of the lever in the foregoing embodiment, the shape of the lever may be simplified by engaging the return preventing means of the lever with the locking means of the first housing. 
   The locking means of the first housing is the resiliently deformable lock arm in the foregoing embodiment. However, the locking means of the lever may be resiliently deformable. 
   The flexible locking piece is the means for preventing the lever from displacing from the standby position to the mount position and also serves as the means for preventing the lever from displacing from the connection position to the standby position in the foregoing embodiment. However, the means for preventing the lever from displacing from the standby position to the mount position and the means for preventing the lever from displacing from the connection position to the standby position may be separate.