Abstract:
Connector assembly ( 2, 3 ) includes internal and external connector housings ( 7, 15 ) matable with each other. The assembly includes a cam projection ( 3 A) provided to one of the internal and external connector housings. The assembly includes a lever ( 8 ) provided rotatably to another one of the internal and external connector housings. The lever defines a cam channel ( 13 ) for guiding the cam projection therein to mate the internal and external connector housings with each other. The assembly includes a false-assembly preventing structure ( 3 Ba,  3 Bb S 1 , S 2 ) operative to prevent false-assembly of the internal and external connector housings at an initial mating. The lever is rotatable to push the cam projection to space the internal and external connector housings off.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The invention relates to a connector assembly with a structure for prevention of false-assembly, and more specifically, to a lever-locking one.  
           [0002]    A conventional lever-locking connector assembly includes internal and external connectors. An internal connector includes an internal connector housing. The housing is formed longitudinally with terminal accommodation chambers. The internal housing is formed transversely with guide protrusions on the both side faces. The chambers include internal terminal fixtures to be inserted and retained.  
           [0003]    An external connector includes an angular tube shaped external connector housing to be mated with the internal connector. The external housing includes external terminal fixtures to be inserted and retained. The external housing has both front edges, which are formed with guide cut-outs rearwardly at a length. Inserted into the cut-outs are the guide protrusions, when the internal and external connectors are mated with each other. The external housing has both side walls which include protruding fulcrums. The fulcrums support rotatably the lever.  
         SUMMARY OF THE INVENTION  
         [0004]    The present invention is directed to a connector assembly with a structure for prevention of false-assembly, which allows prevention of a lever from damage, when connectors are falsely assembled in position.  
           [0005]    A first aspect of the invention provides a connector assembly. The assembly includes a first connector housing. The assembly includes a second connector housings matable with the first connector housing in first and second angular positions relative to the first connector housing. The assembly includes a locking mechanism operative to fix first and second connector housings each other in the first and second angular positions. The assembly includes a guide structure operative to guide the first and second housings in a first angular position and to allow the locking mechanism to be ineffective in a second angular position.  
           [0006]    Preferably, the locking mechanism includes a cam follower mounted to one of the first and second connector housings. The locking mechanism includes a lever member supported rotatably to another one of the first and second connector housings. The lever member defines a cam channel to guide the cam follower therein in the first angular position. The guide structure is operative to space the cam channel and the cam follower from each other in the second angular position.  
           [0007]    Preferably, the lever member is rotatable to displace the cam follower to space the first and second connector housings off.  
           [0008]    Preferably, the guide structure includes a first guide part provided to one of the first and second connector housings. The guide structure includes a second guide part provided to another one of the first and second connector housings. The second guide part is engagable with the first guide member in the first angular position. The guide structure includes a stopper part provided to one of the first and second connector housings. The stopper part is operative to abut against one of first and second guide parts in the second angular position.  
           [0009]    Preferably, one of the first and second guide parts includes a channel. Another one of the first and second guide parts includes a projection insertable into the channel.  
           [0010]    Preferably, the cam channel includes an opening with a first radius relative to a fulcrum. The cam follower and the fulcrum have a first distance therebetween greater than the first radius in the second angular position.  
           [0011]    Preferably, the lever member includes a displacing part adjacent to the cam channel. The displacing part has an outer periphery with a second radius greater than the first radius relative to the fulcrum.  
           [0012]    A second aspect of the invention provides a connector assembly. The assembly includes internal and external connector housings matable with each other. The assembly includes a cam projection provided to one of the internal and external connector housings. The assembly includes a lever provided rotatably to another one of the internal and external connector housings. The lever defines a cam channel for guiding the cam projection therein to mate the internal and external connector housings with each other. The assembly includes a false-assembly preventing structure operative to prevent false-assembly of the internal and external connector housings at an initial mating. The lever is rotatable to push the cam projection to space the internal and external connector housings off.  
           [0013]    Preferably, the false-assembly preventing structure includes a projection provided to one of the internal and external connector housings. The structure includes a stopper provided to another one of the internal and external connector housings. The stopper is operative to abut against the projection at the false-assembly. Thus, the lever is rotatable to push the cam projection off. 
       
    
    
     BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS  
       [0014]    These and other features, aspects, and advantage of the present invention will become better under stood with reference to the following description, appended claims, and accompanying drawings where:  
         [0015]    [0015]FIG. 1 is an exploded perspective view of an embodiment of a connector with a structure for prevention of false-assembly according to the embodiment of the invention;  
         [0016]    [0016]FIG. 2 is an elevation view of the external connector in FIG. 1;  
         [0017]    [0017]FIG. 3 is an elevation view of an internal connector;  
         [0018]    [0018]FIG. 4 is a side view illustrating internal and external connectors in false-assembly; and  
         [0019]    [0019]FIG. 5 is a side view illustrating internal and external connectors in false-assembly.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0020]    An embodiment of the invention will be described with reference to drawings.  
         [0021]    As shown in FIG. 1, connector assembly  1  according to the invention includes the structure for prevention of false-assembly. Connector assembly  1  includes external and internal connectors  2 ,  3  to be mated and electrically joined each other. External and internal connectors  2 ,  3  have wires  4  mounted thereto. Respective wires  4  include respective terminal ends mounted to respective terminal fixtures  5 ,  6 .  
         [0022]    External connector  2 , in FIG. 2, includes external connector housing  7 . Connector  2  includes lever  8  rotatably supported on housing  7 . Housing  7  includes terminal accommodation chambers (not shown on Figs.) longitudinally therethrough. Each chamber houses fixture  5  connected to the terminal end of wire  4 . Fixtures  5  are arranged in parallel to space away at an interval each other.  
         [0023]    Housing  7  has both side walls with front edges which define guide cut-outs  9  rearwardly at a predetermined length. Cut-outs  9  have guide protrusions  3 A as a cam pin of internal connector  3  as described later, which are inserted when internal and external connectors  2 ,  3  are mated.  
         [0024]    Both side walls of housing  7  each have protruding fulcrum  10 , which rotatably supports lever  8 . Lever  8  has a pair of arm plates  11  which are disposed along the outer faces of the both side walls. Lever  8  has connection operation part  12  extending between the ends of plates  11  for connection. Plates  11  have fulcrum holes at portions, where fulcrums  10  are rotatably fitted. The fitting of fulcrums  10  into the holes allows the mounting of lever  8 . Lever  8  is normally biased by a coil spring  103 , shown on FIG. 4, in a certain rotational direction. Plates  11  are formed with cam channels  13 . Cam channels  11  lap with cut-outs  9  at the ends. When protrusions  3 A of connector  3  are inserted into cut-outs  9  of housing  7 , the rotation of lever  8  against coil spring  103  under biasing force allows the introduction of protrusions  3 A inwardly into cut-outs  9 .  
         [0025]    Specifically, according to the embodiment, housing  7  has recesses or channels  14   a ,  14   b  at both sides of the lower part on the front end, which serves as the insertion of ribs or projections  3 B ( 3 Ba and  3 Bb). Channels  14   a ,  14   b  are disposed in correspondence with projections  3 Ba,  3 Bb of connector  3  for prevention of false-assembly. Channels  14   a ,  14   b  are recessed on the inner wall of housing  7 , extending rearwardly from the front end.  
         [0026]    Connector  3 , in FIG. 1, has fixtures  6  with wires  4  each inserted into chambers  16  for retention. Fixtures  6  with wires  4  are arranged in parallel to space away at an interval each other.  
         [0027]    Housing  15  has both side walls from which guide protrusions  3 A protrude. Protrusions  3 A are inserted into cut-outs  9  and cam channels  13 . Protrusions  3 A are each disposed in a vertical central position on the side wall of housing  15 , to transmit pulling force from lever  8  uniformly to whole connector  3 .  
         [0028]    The front end of housing  15 , in FIGS.  1  to  3 , has outwardly protruding projections  3 Ba,  3 Bb, which are disposed in correspondence with channels  14   a ,  14   b  of housing  7  in angular position. When connectors  2 ,  3  are mated correctly with each other, the insertion of respective projections  3 Ba,  3 Bb into respective channels  14   a ,  14   b  allows the fitting of connector  3  into connector  2 . Connector  3  allows to be mated with connector  2  at an angular displacement of 180 degrees from a correct position. When connector  3  is inserted in a vertically reversed position, or is displaced angularly at 180 degrees from the correct position, respective projections  3 Ba,  3 Bb abut against respective regions S 1 , S 2  of both sides at the upper part of opening on the front end wall  7   a  of housing  7  (stopper region indicated by the dotted line), to prevent the assembly of connectors  2 ,  3 . Regions S 1 , S 2  each include a closed wall at angular displacement of 180 degrees from channels  14   a ,  14   b , which stops each projection  3 A,  3 B.  
         [0029]    In FIG. 4, protrusion  3 A has peripheral face  3 Aa away from the center of fulcrum  10  at a relative distance of D 1 . The openings  11 B of cut-outs  9  and channels  13  are away from the center of fulcrum  10  at a radius of R 1 . R 1  is greater than D 1 . The relative abutting distance between respective projections  3 Ba,  3   b  and respective regions S 1 , S 2  is set at D 2  identical to the number of subtracting R 1  from 2D 1  or (2D 1 -R 1 ).  
         [0030]    Inserted into housing  15  is connector  3  in a vertically reversed position. In this state, Both side projections  3 Ba,  3 Bb of housing  15  abut against stopper regions S 1 , S 2  of end wall  7   a  of housing  7 . Protrusions  3 A do not enter in the openings  11 B of cut-outs  9  and cam channels  13 , to be prevented from the insertion at the front position. When an operator rotates falsely lever  8  in the direction indicated by the arrow, lever  8  does not engage with protrusions  3 A to be easily rotated.  
         [0031]    Plates  11  of lever  8  abut against protrusions  3 A during the rotation to push protrusion  3 A away from connector  2 . In order to obtain the operation, plates  11  of lever  8  are formed with bulges  11 A to be abutted against protrusions  3 A. The plates  11  each have bulge  11 A which includes an outer periphery with a maximum radius of R 2  greater than R 1  relative to fulcrum  10 . The pushing of bulges  11 A against protrusions  3 A allows connector  3  to be pushed away from connector  2  (in the direction indicated by the arrow in FIG. 5) for discharge. The result prevents the false-assembly between connectors  2 ,  3  and the damage of lever  8  due to the exertion of forced stress on lever  8 .  
         [0032]    While the preferred embodiment of the present invention have been described using specific terms, such description is for illustrative purposes, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims. For example, connector housing  7  may be inversely formed with the projections for prevention of false-assembly, while connector housing  15  may be formed with the channels for insertion of the projections.  
         [0033]    According to the invention, the false-assembly preventing structure prevents an operator from falsely assembling of internal and external connectors in an initial assembly, previously. The false-assembly preventing structure allows rotating lever to push against a cam projection for spacing internal and external connectors off. The spacing allows the internal and external connectors to be easily identified in false-assembly.  
         [0034]    The projection of one connector housing abuts against the stopper of another connector housing in false-assembly. The abutment advantageously prevents false-assembly with a simple structure. The stopper allows the lever to push against the cam projection in an initial-assembly. This advantageously prevents the damage of the lever during the rotation.  
         [0035]    The entire contents of Japanese Patent Application P2001 -133182 (filed on Apr. 27, 2001) are incorporated herein by reference.