Patent Publication Number: US-2015079826-A1

Title: Lever-type connector

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of PCT application No. PCT/JP2013/064139, which was filed on May 15, 2013 based on Japanese patent application (patent application 2012-117826) filed on May 23, 2012, whose contents are incorporated herein by reference. Also, all the references cited herein are incorporated as a whole. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to a lever-type connector. 
     2. Background Art 
       FIG. 12  shows an example of a conventional lever-type connector. 
     This lever-type connector  100  is disclosed in Japanese Patent No. 3442661, and includes a first connector housing  110 , a second connector housing  120  which is fitted and connected together with the first connector housing  110 , and a fitting control lever  130  which is mounted rotatably on the first connector housing  110 . 
     The second connector housing  120  has an outer angularly tubular wall portion (a hood portion)  121  into which the first connector housing  110  is inserted. 
     The fitting control lever  130  is mounted rotatably on boss portions  111  which are provided on outer surfaces of the first connector housing  110  so as to project therefrom as a lever member which reduces operation forces with which the first connector housing  110  and the second connector housing  120  are fitted together and are released from such a fitted state. 
     As shown in  FIG. 12 , the fitting control lever  130  includes a pair of lever main bodies  131  which are oppositely disposed so as to hold a pair of outer surfaces of the first connector housing  110  therebetween, a connecting member  132  which connects together ends of the pair of lever main bodies  131 , rotation fulcrum or pivot holes  133  which are formed individually in the lever main bodies  131  so as to be brought into rotational engagement with the boss portions  111  which are provided on the outer surfaces of the first connector housing  110 , projecting portions  134  functioning as action points which are brought into engagement with lever locking holes  122  which are formed in outer surfaces of the outer angularly tubular wall portion  121  in an initial fitting stage of the first connector housing  110  and the second connector housing  120  in which both the connector housings are registered with their fitting initiating position. 
     In the case of the depicted example, the connecting member  132  doubles as a force application point to which a force is applied when the lever main bodies  131  are rotated about the boss portions  111 . 
     In the lever-type connector  100  of Japanese Patent No. 3442661, the first connector housing  110  and the second connector housing  120  are fitted and connected together according to the following procedure. 
     Firstly, as shown in the figure, the fitting control lever  130  is mounted rotatably on the first connector housing  110 . Following this, as indicated by an arrow X1 in  FIG. 12 , a front end portion of the first connector housing  110  is inserted into an interior of the outer angularly tubular wall portion  121  of the second connector housing  120 , and the first connector housing  110  and the second connector housing  120  are registered with their fitting initiating position. Then, the projecting portions  134 , functioning as action points, of the fitting control lever  130  are brought into engagement with the lever locking holes  122  in the second connector housing  120 . 
     Following this, the connecting member  132  of the fitting control lever  130  is pressed downwards so as to rotate the fitting control lever  130  as indicated by an arrow R1 in the figure. The rotating operation of the fitting control lever  130  draws the second connector housing  120  towards the first connector housing  110 , whereby both the connector housings are fitted together completely. 
     When the connector housings which are fitted together so are released from the fitted state, the connecting member  132  is rotated in an opposite direction to the direction indicated by the arrow R1 in the figure, whereby the connector housings are separated from each other. 
     In addition, Patent Literature, JP-A-7-135046, discloses a lever-type connector having a configuration in which a first connector housing and a second connector housing which are registered with their fitting initiating position are fitted and connected together by means of a fitting control lever (which is called a slide 14 in JP-A-7-135046) which is inserted to be mounted in the first connector housing. 
     The fitting control lever of JP-A-7-135046 is inserted into the first connector housing in a direction which is at right angles to a direction in which both the connector housings are fitted together. In this fitting control lever, guide grooves are formed in an inclined fashion so that lever engagement shaft portions which are provided on outer surfaces of the second connector housing so as to project therefrom can slide therealong. Then, both the connector housings are fitted to each other by pulling in the lever engagement shaft portions along the inclined guide grooves in the direction in which the connector housings are fitted together. 
     SUMMARY 
     In the case of the lever-type connectors of Patent Literatures, Japanese Patent No. 3442661 and JP-A-7-135046, however, the fitting control lever cannot be removed from the first connector housing in such a state that both the connector housings are fitted and connected together. 
     Because of this, in the case of the lever-type connectors of Japanese Patent No. 3442661, the weight of the fitting control lever is kept additionally applied to the connector even after both the connector housings are completely fitted and connected together, resulting in a factor which calls for an increase in weight of the connector. 
     In addition, in the case of the lever-type connectors of Patent Literatures, Japanese Patent No. 3442661 and JP-A-7-135046, the connector has to be accompanied by the fitting control lever in any case, leading to a problem that the production costs are increased due to the increase in the number of constituent parts involved. 
     Then, the invention has been made to solve the problems inherent in the conventional lever-type connectors, and an object of the invention is to provide a lever-type connector which can realize a reduction in production cost and weight in use by reducing the number of constituent parts involved. 
     The object of the invention is attained by the following configurations. 
     (1) A lever-type connector comprising: 
     a first connector housing: 
     a second connector housing which is fitted and connected to the first connector housing; and 
     a fitting control lever which is mounted on the first connector housing as a fitting assist member; wherein 
     the first connector housing comprises: 
     a housing main body including a plurality of terminal insertion holes; and 
     a pair of first lever engagement shaft portions which are provided individually on a pair of outer side walls of the housing main body so as to project therefrom; wherein 
     the second connector housing comprises: 
     an outer angularly tubular wall portion which fits on an outer circumference of the first connector housing; 
     a pair of second lever engagement shaft portions that are provided individually on a pair of inner side surfaces of the outer angularly tubular wall portion which oppositely face the pair of outer side walls of the first connector housing so as to project therefrom and which are positioned a predetermined spacing distance opposite to the first lever engagement shaft portions in a direction in which both the connector housings are fitted together when the first connector housing and the second connector housing are registered with their fitting initiating position; and 
     guide ribs which are provided individually on the pair of inner side surfaces so as to extend at a first inclination angle which is set to a predetermined inclination angle with respect to the direction in which both the connector housings are fitted together; wherein 
     the fitting control lever comprises: 
     a pair of lever main bodies which are disposed opposite to each other so as to be inserted into gaps defined between the pair of outer side walls of the first connector housing and the pair of inner surfaces of the outer angularly tubular wall portion; 
     first boss introduction grooves that are formed individually on inner surfaces of the pair of main bodies along the direction in which both the connector housings are fitted together and which guide the first lever engagement shaft portions to a first mounting initiating position when the pair of lever main bodies are placed on the pair of outer side walls; 
     first fitting control grooves along which the first lever engagement shaft portions which are situated in the first mounting initiating position slide when the fitting control lever which is mounted on the first connector housing is pulled out of the first connector housing at the first inclination angle and which are formed so as to communicate with the first boss introduction grooves at a second inclination angle at which portions of the first fitting control grooves which are far away from the first mounting initiating position intersect extensions of the guide ribs which extend at the first inclination angle; 
     second boss introduction grooves that are formed individually on outer surfaces of the pair of lever main bodies along the direction in which both the connector housings are fitted together and which guide the second lever engagement shaft portions to a second mounting initiating position when the first connector housing on which the fitting control lever is mounted in such a state that the first lever engagement shaft portions are situated in the first mounting initiating position and the second connector housing are registered with their fitting initiating position; and 
     second fitting control grooves along which the second lever engagement shaft portions which are situated in the second mounting initiating position slide when the fitting control lever which is mounted in such a state that the second lever engagement shaft portions are situated in the second mounting initiating position is pulled out of the second connector housing at the first inclination angle and which are formed so as to communicate with the second boss introduction grooves at the first inclination angle; and wherein 
     both the connector housings are fitted and connected together, by pulling out the fitting control lever from both the connector housings in such a state that the first connector housing and the second connector housing are registered with their fitting initiating position, the first lever engagement shaft portions are situated in the first mounting initiating position, and the second lever engagement shaft portions are situated in the second mounting initiating position. 
     The fitting control lever may be adapted to reduce operation forces with which the first connector housing and the second connector housing are fitted together and are released from such a fitted state. 
     The first connector housing may further comprise a locking securing portion that is provided on a side surface of the housing main body and which is brought into engagement with the second connector housing when the first connector housing and the second connector housing are fitted and connected together completely to thereby lock both the connector housings in a connected state. 
     The second connector housing may further comprise a securement ensuring portion which is brought into engagement with the locking securing portion when the first connector housing and the second connector housings are fitted and connected together completely to thereby lock both the connector housings in a connected state 
     The fitting control lever may further comprise temporary securing pieces which are brought into engagement with the guide ribs when the second lever engagement shaft portions are situated in the second mounting initiating position to thereby restrain the fitting control lever from moving along the direction in which both the connector housings are fitted together to be disengaged from the second connector housing. 
     (2) The lever-type connector according to the above (1), wherein 
     the first lever engagement shaft portions and the second lever engagement shaft portions are disposed so as to be aligned with each other in a direction which is at right angles to the direction in which both the connector housings are fitted together. 
     (3) The lever-type connector according to the above (1), wherein 
     the first connector housing comprises temporary lever securing portions which are positions away from the first lever engagement shaft portions in the direction which is at right angles to the direction in which both the connector housings are fitted together, and wherein 
     the fitting control lever comprises positioning portions which are brought into engagement with the temporary lever securing portions when the first lever engagement shaft portions which fit in the first boss introduction grooves reach the first mounting initiating position. 
     (4) The lever-type connector according to the above (1), wherein 
     the first fitting control grooves and the second fitting control grooves are formed into a curvilinear configuration so that a moving locus of the fitting control lever produced when the fitting control lever is pulled out becomes curvilinear. 
     According to the configuration described under (1) above, as an operating procedure of fitting and connecting the connector housings together, firstly, the fitting control lever is mounted on the first connector housing so that the pair of first lever engagement shaft portions on the first connector housing fit in the pair of first boss introduction grooves on the fitting control lever, and the fitting control lever is fixed to the first connector housing in a temporarily secured state in which the first lever engagement shaft portions reach the first mounting initiating position. 
     Following this, the first connector housing to which the fitting control lever is temporarily secured is inserted into the outer angularly tubular wall portion of the second connector housing along the direction in which both the connector housings are fitted together, whereby the first connector housing and the second connector housing are registered with their fitting initiating position. 
     With the first connector housing and the second connector housing registered with their fitting initiating position, the pair of second lever engagement shaft portions of the second connector housing fit in the second boss introduction grooves of the fitting control lever and reach the second mounting initiating position on the second boss introduction grooves. 
     In addition, with the first connector housing and the second connector housing registered with their fitting initiating position, the temporary securing pieces provided on the fitting control lever are in engagement with the guide ribs on the second connector housing. Then, by the engagement of the temporary securing pieces with the guide ribs, the fitting control lever is restrained from moving along the direction in which both the connector housings are fitted together to be disengaged from the second connector housing, whereby the fitting control lever is temporarily secured to the first connector housing and the second connector housing. 
     Following this, the fitting control lever is pulled out of the first connector housing and the second connector housing which are registered with their fitting initiating position. When the fitting control lever is pulled out so, the first lever engagement shaft portions which are situated in the first mounting initiating position slide on the first fitting control grooves which are formed so as to communicate with the first boss introduction grooves. Additionally, the second lever engagement shaft portions which are situated in the second mounting initiating position slide on the second fitting control grooves which are formed so as to communicate with the second boss introduction grooves. 
     Then, since the inclination angles of the first and second fitting control grooves set so that the portions of the first fitting control grooves on the fitting control lever which are away from the first mounting initiating position intersect the second fitting control grooves, as the fitting control lever is pulled out progressively, the first lever engagement shaft portions on the first fitting control grooves are moved towards the second lever engagement shaft portions on the second fitting control grooves, whereby the connector housings are fitted deeply together. 
     Then, when the fitting control lever is pulled out of both the connector housings, the connector housings are fitted and connected together completely, and at the same time, the fitting control lever is disengaged from both the connector housings. Additionally, when both the connector housings are fitted and connected together completely, a locking securing portion of the first connector housing is brought into engagement with a securement ensuring portion of the second connector housing, whereby both the connector housings are locked in the connected state. 
     Namely, according to the configuration described under (1) above, the connector housings are configured so as to be fitted deeply together by pulling out the fitting control lever. When the connector housings are fitted and connected together completely, the fitting control lever has been pulled out of both the connector housings and is then disengaged therefrom. Because of this, the weight of the fitting control lever is not applied to the connector when in use, thereby making it possible to realize a reduction in weight of the connector when in use. 
     Additionally, the fitting control lever that is disengaged from the connector housings can be used to build up another lever-type connector. Because of this, the first connector housing and the second connector housing excluding the fitting control lever only have to be prepared as a set of parts for a normal lever-type connector, thereby making it possible to realize a reduction in the number of parts involved. 
     According to the configuration described under (2) above, the first boss introduction grooves and the second boss introduction grooves on the fitting control lever are formed on the front and rear sides of the lever main bodies so as to be aligned with each other in the direction which is at right angles to the direction in which both the connector housings are fitted together. Therefore, the first boss introduction grooves and the second boss introduction grooves can be designed to be disposed the same spacing distance from the same reference plane, thereby making it possible to facilitate the disposition design of the first boss introduction grooves and the second boss introduction grooves. 
     According to the configuration described under (3) above, when the fitting control lever is mounted on the first connector housing, the first lever engagement shaft portions on the first connector housing are positioned in the first mounting initiating position by the first boss introduction grooves. Further, the positioning portions on the fitting control lever are brought into abutment with the temporary lever securing portions of the first connector housing, whereby the fitting control lever is temporarily fixed to the first connector housing. 
     In other words, the fitting control lever mounted on the first connector housing is positioned at such two locations as the first boss introduction grooves and the positioning portions, and therefore, it is possible to ensure the stable positioning of the fitting control lever with respect to the first connector housing, whereby the loosening of the fitting control lever relative to the first connector housing is made difficult to occur. Because of this, the inadvertent displacement of the fitting control lever can be prevented which would otherwise occur when the first connector housing and the second connector housing are registered with their fitting initiating position, thereby making it possible to facilitate the registration of the first and second connector housings with their fitting initiating position. 
     Consequently, the fitting and connecting of the first and second connector housings can be facilitated. 
     According to the configuration described under (4) above, when the fitting control lever is pulled out of the connector housings, the displacement of the fitting control lever in a direction which is at right angles to the direction in which both the connector housings are fitted together can be reduced, compared with the case where the moving locus of the fitting control lever is rectilinear. Because of this, the working space necessary for the pulling out operation of the fitting control lever can be reduced, thereby making it possible to realize a highly compact mounting of the lever-type connector. 
     According to the lever-type connector of the invention, the fitting control lever is disengaged from the connector housings after the connector housings are fitted and connected completely, and therefore, it is possible to realize a reduction in weight of the connector when in use. 
     In addition, the fitting control lever that is disengaged from the connector housings can also be used to build up another lever-type connector. Therefore, the first connector housing and the second connector housing excluding the fitting control lever only have to be prepared as a set of parts for a normal lever-type connector, thereby making it possible to realize a reduction in the number of parts involved. 
     Thus, the invention has been described briefly. Further, the details of the invention will be made clearer by perusing the following modes for carrying out the invention (hereinafter, referred to as “embodiments”) by reference to accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of a lever-type connector according to a first embodiment of the invention. 
         FIG. 2  is a view of a second connector housing shown in  FIG. 1  as viewed in a direction indicated by an arrow A. 
         FIG. 3  is a sectional view of the second connector housing taken along a line B-B in  FIG. 2 . 
         FIG. 4  is a side view of a fitting control lever shown in  FIG. 1 . 
         FIG. 5  is a view of the fitting control lever as viewed in a direction indicated by an arrow C in  FIG. 4 . 
         FIG. 6  is a sectional view of the fitting control lever taken along a line D-D in  FIG. 5 . 
         FIG. 7  is a side view showing a state occurring before a first connector housing on which the fitting control lever is temporarily locked is inserted into the second connector housing. 
         FIG. 8  is a side view showing a state in which the first connector housing and the second connector housing are registered with their fitting initiating position. 
         FIG. 9  is a side view showing a state in which the fitting control lever is being pulled out of both the connector housings which are registered with their fitting initiating position. 
         FIG. 10  is a side view showing a state in which with the fitting control lever pulled out of both the connector housings, the connector housings are fitted and connected together completely. 
         FIG. 11  is a comparison diagram between a lever-type connector according to a second embodiment which is improved so that a space necessary for the fitting control lever to be pulled out is reduced and the lever-type connector according to the first embodiment. 
         FIG. 12  is an exploded perspective view of a conventional lever-type connector. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Hereinafter, preferred embodiments of lever-type connectors according to the invention will be described in detail by reference to the drawings. 
       FIGS. 1 to 10  show a lever-type connector according to a first embodiment of the invention.  FIG. 1  is an exploded perspective view of a lever-type connector according to a first embodiment of the invention,  FIG. 2  is a view of a second connector housing shown in  FIG. 1  as viewed in a direction indicated by an arrow A,  FIG. 3  is a sectional view of the second connector housing taken along a line B-B in  FIG. 2 ,  FIG. 4  is a side view of a fitting control lever shown in  FIG. 1 ,  FIG. 5  is a view of the fitting control lever as viewed in a direction indicated by an arrow C in  FIG. 4 ,  FIG. 6  is a sectional view of the fitting control lever taken along a line D-D in  FIG. 5 ,  FIG. 7  is a side view showing a state occurring before a first connector housing on which the fitting control lever is temporarily locked is inserted into the second connector housing,  FIG. 8  is a side view showing a state in which the first connector housing and the second connector housing are registered with their fitting initiating position,  FIG. 9  is a side view showing a state in which the fitting control lever is being pulled out of both the connector housings which are registered with their fitting initiating position, and  FIG. 10  is a side view showing a state in which with the fitting control lever pulled out of both the connector housings, the connector housings are fitted and connected together completely. 
     As shown in  FIG. 1 , the lever-type connector  1  of the first embodiment includes a first connector housing  10 , a second connector housing  20  which is fitted and connected together with the first connector housing  10 , and a fitting control lever  30 . It should be noted that an arrow Z1 shown in  FIG. 1  denotes a direction in which the fitting control lever  30  is placed on to the first connector housing  10 . Additionally, an arrow Z2 shown in the same figure denotes a direction in which the first connector housing  10  is fitted into the second connector housing  20  for installation therein. 
     As shown in  FIG. 1 , the first connector housing  10  includes a housing main body  11  which includes, in turn, a plurality of terminal insertion holes  11   a , a pair of first lever engagement shaft portions (boss portions)  12 , a locking securing portion  13 , and a pair of temporary lever securing portions  14 . 
     The housing main body  11  has a rectangular parallelepiped shape as an external shape. 
     The pair of first lever engagement shaft portions  12  are cylindrical shafts which are provided individually on a pair of outer side walls  11   b  of the housing main body  11  so as to project therefrom. The pair of outer side walls  11   b  are side walls which stand opposite to each other in a direction indicated by an arrow X2 in  FIG. 1 . 
     As shown in  FIG. 1 , the locking securing portion  13  is provided on a side surface  11   c  of the housing main body  11 . The side surface  11   c  is a surface of an outer side wall which differs from the pair of outer side walls  11   b  described above. 
     As shown in  FIG. 1 , the locking securing portion  13  of this embodiment includes an elastic piece  131  which rises from a front end side of the side surface  11   c  and extends towards a rear end side of the side surface  11   c , and a securing projection  132  which is provided on the elastic piece  131  so as to project therefrom. The locking securing portion  13  is brought into engagement with the second connector housing  20  when the first connector housing  10  and the second connector housing  20  are fitted and connected together completely to thereby lock both the connector housings in a fittingly connected state. 
     The pair of temporary lever securing portions  14  are projecting portions which are provided on the pair of outer side walls  11   b . The respective temporary lever securing portion  14  are provided on the pair of outer side walls  11   b  in positions which are spaced away from the first lever engagement shaft portions  12  in a direction which is at right angles (a direction indicated by an arrow Y2 in  FIG. 1 ) to a direction in which the connector housings are fitted to each other (a direction indicated by an arrow Z2 in  FIG. 1 ). 
     As shown in  FIGS. 1 to 3 , the second connector housing  20  includes an outer angularly tubular wall portion (a hood portion)  21 , a pair of second lever engagement shaft portions (boss portions)  22 , guide ribs  23 , and a securement ensuring portion  24 . 
     The outer angularly tubular wall portion  21  is an angularly tubular portion that is formed on a front end side of the second connector housing  20  and which fits on an outer circumference of the first connector housing  10 . In this outer angularly tubular wall portion  21 , inner side surfaces  211   b , which are inner surfaces of a pair of side walls  211  which stand opposite to each other, are surfaces which stand opposite to the pair of outer side walls  11   b  of the first connector housing  10 . 
     The pair of second lever engagement shaft portions  22  are cylindrical shafts which are provided individually on the pair of inner side surfaces  211   b  of the outer angularly tubular wall portion  21 . The pair of second lever engagement shaft portions  22  are positioned a predetermined spacing distance L1 (refer to  FIG. 8 ) opposite to the first lever engagement shaft portions  12  in the direction in which both the connector housings are fitted to each other (the direction indicated by the arrow Z2 in  FIG. 8 ) when the first connector housing  10  and the second connector housing  20  are registered with their fitting initiating position as shown in  FIG. 8 . 
     In the case of this embodiment, the first lever engagement shaft portions  12  and the second lever engagement shaft portions  22  are disposed so as to be aligned with each other in a direction which is at right angles to the direction in which both the connector housings are fitted to each other. Consequently, as shown in  FIG. 8 , the first lever engagement shaft portions  12  and the second lever engagement shaft portions  22  are aligned on a single straight line m1 which extends in the direction in which both the connector housings are fitted together. 
     As shown in  FIG. 3 , the guide ribs  23  are provided individually on the pair of inner side surfaces  211   b  so as to extend at a first inclination angle θ1 with respect to the direction in which both the connector housings are fitted together (the direction indicated by the arrow Z2 in  FIG. 1 ). 
     The securement ensuring portion  24  is brought into engagement with the locking securing portion  13  of the first connector housing  10  so as to lock both the connector housings in the connected state when the first connector housing  10  and the second connector housing  20  are fitted and connected together completely as shown in  FIG. 10 . 
     The fitting control lever  30  is mounted on the first connector housing  10  as a fitting assist member which reduces operation forces with which the first connector housing  10  and the second connector housing  20  are fitted together or are released from the fitted state. 
     As shown in  FIGS. 4 to 6 , the fitting control lever  30  includes a pair of lever main bodies  31 , first boss introduction grooves  32 , first fitting control grooves  33 , second boss introduction grooves  34 , second fitting control grooves  35 , temporary securing pieces  36 , and positioning portions  37 . 
     The pair of lever main bodies  31  are thick plate-like members which are disposed opposite to each other so as to be inserted into corresponding gaps defined individually between the pair of outer side walls  11   b  of the first connector housing  10  and the pair of inner side walls  211   b  of the outer angularly tubular wall portion  21  of the second connector housing  20 . As shown in  FIGS. 4 to 6 , proximal ends of the pair of lever main bodies  31  are connected together by a handle portion  38 . The handle portion  38  is a portion to be gripped on when the fitting control lever  30  is pulled out of the connector housings. 
     As shown in  FIG. 6 , the first boss introduction groove  32  is formed on an inner surface of each of the pair of lever main bodies  31  so as to extend along a straight line m2. The straight line m2 shown in  FIG. 6  is a straight line which extends in the direction in which both the connector housing are fitted together. Namely, the first boss introduction groove  32  is formed along the direction in which both the connector housings are fitted together. 
     The first boss introduction grooves  32  guide the first lever engagement shafts  12  to a first mounting initiating position P1 when the pair of lever main bodies  31  are placed on the pair of outer side walls  11   b  of the first connector housing  10  as shown in  FIG. 7 . The first mounting initiating position P1 is a terminating end of the first boss introduction grooves  32  where the first lever engagement shafts  12  are stopped. 
     As shown in  FIG. 6 , the first fitting control groove  33  is formed on the inner surface of each of the pair of lever main bodies  31  so as to extend along a straight line m4. Additionally, this first fitting control groove  33  is formed so as to communicate with the terminating end of the first boss introduction groove  32 . 
     As shown in  FIG. 6 , the straight line m4 is a straight line which extends at a second inclination angle θ2 with respect to the direction in which both the connector housings are fitted together (the direction indicated by the arrow Z2 in  FIG. 1 ). The second inclination angle θ2 is set to an angle which is larger than the first inclination angle θ1. In other words, the second inclination angle θ2 is an inclination angle at which an end portion (a right end portion in  FIG. 4 ) of the straight line m4 which is spaced far away from the first mounting initiating position P1 intersects an extension of the guide rib  23  which is inclined at the first inclination angle θ1. Consequently, the straight line m4 intersects the extension of the guide rib  23  which is inclined at the first inclination angle θ1 at the end portion thereof which is spaced far away from the first mounting initiating position P1. 
     The first fitting control groove  33  is a groove along which the first lever engagement shaft portion  12  which lies in the first mounting initiating position P1 slides when the fitting control lever  30  mounted on the first connector housing  10  is pulled out of the first connector housing  10  along the first inclination angle θ1 as indicated by an arrow X3 in  FIG. 7 . 
     The second boss introduction grooves  34  are formed individually on outer surfaces of the pair of lever main bodied  31  so as to extend along a straight line m3 as shown in  FIG. 4 . The straight line m3 is a straight line which extends along the direction in which both the connector housings are fitted together (the direction indicated by the arrow Z2 in  FIG. 1 ). Additionally, the straight line m3 is a straight line which is superposed on the straight line m2 shown in  FIG. 6 . Namely, the second boss introduction grooves  34  are formed on the outer surfaces of the pair of lever main bodies  31  along the direction in which both the connector housings are fitted together (the direction indicated by the arrow Z2 in  FIG. 1 ). 
     The second boss introduction grooves  34  guide the second lever engagement shaft portions  22  to a second mounting initiating position P2 as shown in  FIG. 8  when the first connector housing  10  on which the fitting control lever  30  is mounted with the first lever engagement shaft portions  12  lying in the first mounting initiating position P1 and the second connector housing  20  are registered with their fitting initiating position. This second mounting initiating position P2 is a position which coincides with a terminating end of the second boss introduction grooves  34  and where the second lever engagement shaft portions  22  are stopped. 
     As shown in  FIG. 4 , the second fitting control grooves  35  are formed individually on the outer surfaces of the pair of lever main bodies  31  so as to extend along a straight line m5. Additionally, the second fitting control grooves  35  are formed so as to communicate with the terminating ends of the second boss introduction grooves  34 . 
     The straight line m5 is a straight line which extends at the first inclination angle θ1 (the inclination angle of the guide ribs  23 ) with respective to the direction in which both the connector housings are fitted together (the direction indicated by the arrow Z2 in  FIG. 1 ). 
     The second fitting control groove  35  is a groove along which the second lever engagement shaft portion  22  which lies in the second mounting initiating position P2 slides when the fitting control lever  30  which is mounted on the first connector housing  10  with the second lever engagement shaft portion  22  situated in the second mounting initiating position P2 is pulled out of the second connector housing  20  at the first inclination angle θ1 as indicated by an arrow X4 in  FIG. 8 . 
     As shown in  FIG. 4 , the temporary securing piece  36  includes an elastic piece  36   a  which extends from an upper edge side to a lower edge side of the lever main body  31  along the direction in which both the connector housings are fitted together and a securing elongated projection  36   b  which is formed so as to protrudes outwards from a lower edge of the elastic piece  36   a . The securing elongated projection  36   b  is a rib-like projection which extends at the first inclination angle θ1 at which the guide rib  23  on the second connector housing  20  extends. 
     As shown in  FIG. 8 , the temporary securing piece  36  is brought into engagement with the guide rib  23  when the second lever engagement shaft portion  22  comes to be situated in the second mounting initiating position P2 to thereby restrain the fitting control lever  30  from moving along the direction in which both the connector housings are fitted together so as to be disengaged from the second connector housing  20 . 
     As shown in  FIG. 4 , the positioning portion  37  includes a pair of projecting pieces  37   a ,  37   b  which project in a length direction of the lever main body  31  in upper and lower positions of a front end of the lever main body  31 . 
     As shown in  FIG. 7 , the positioning portion  37  is brought into abutment with the lever temporary securing portion  14  in such a way that the pair of projecting pieces  37   a ,  37   b  hold the lever temporary securing portion  14  therebetween from thereabove and therebelow so as to position the first connector housing  10  at a front end portion of the lever main body  31  when the first lever engagement shaft portion  12  which fits in the first boss introduction groove  32  reaches the first mounting initiating position P1. 
     In the lever-type connector  1  of this embodiment, by pulling out the fitting control lever  30  from both the connector housings in such a state that the first connector housing  10  and the second connector housing  20  are registered with their fitting initiating position with the first lever engagement shaft portions  12  lying in the first mounting initiating position P1 and the second lever engagement shaft portions  22  lying in the second mounting initiating position P2 as shown in  FIG. 8 , the connector housings are fitted and connected to each other. 
     Next, an operating procedure of fitting and connecting together the connector housings of the lever-type connector  1  of this embodiment and the working effect thereof will be described based on  FIGS. 7 to 10 . 
     In the case of this embodiment, firstly, the fitting control lever  30  is mounted on the first connector housing  10  so that the pair of first lever engagement shaft portions  12  of the first connector housing  10  fit in the pair of boss introduction grooves  32  on the fitting control lever  30 . Then, the fitting control lever  30  is fixed to the first connector housing  10  in a temporarily secured state in which the first lever engagement shaft portions  12  reach the first mounting initiating position P1 as shown in  FIG. 7 . 
     Following this, the first connector housing  10  to which the fitting control lever  30  is temporarily secured is inserted into the outer angularly tubular wall portion  21  of the second connector housing  20  along the direction in which both the connector housings are fitted together as indicated by an arrow Z2 in  FIG. 7 . Then, the first connector housing  10  and the second connector housing  20  are registered with their fitting initiating position as shown in  FIG. 8 . 
     With the first connector housing  10  and the second connector housing  20  registered with their fitting initiating position, as shown in  FIG. 8 , the pair of second lever engagement shaft portions  22  of the second connector housing  20  fit in the second boss introduction groves  34  on the fitting control lever  30  and reach the second mounting initiating position P2 on the second boss introduction grooves  34 . 
     Additionally, with the first connector housing  10  and the second connector housing  20  registered with their fitting initiating position, the temporary securing pieces  36  which are provided on the fitting control lever  30  are brought into engagement with the corresponding guide ribs  23  on the second connector housing  20 . Then, by engagement of the temporary securing pieces  36  with the guide ribs  23 , the fitting control lever  30  is restrained from moving along the direction in which both the connector housings are fitted together to thereby be disengaged from the second connector housing  20 . Thus, as shown in  FIG. 8 , the fitting control lever  30  and the first connector housing  10  are temporarily secured to the second housing  20 . 
     Next, the fitting control lever  30  is pulled out in a direction indicated by an arrow X4 shown in  FIG. 8  from the first connector housing  10  and the second connector housing  20  which are registered with their fitting initiating position. Then, by pulling out the fitting control lever  30  in this way, as shown in  FIG. 9 , the first lever engagement shaft portions  12  which are situated in the first mounting initiating position P1 slide over the first fitting control grooves  33  which are formed so as to communicate with the first boss introduction grooves  32 . Additionally, the second lever engagement shaft portions  22  which are situated in the second mounting initiating position P2 slide over the second fitting control grooves  35  which are formed so as to communicate with the second boss introduction grooves  34 . 
     The respective pairs of fitting control grooves are formed so as to extend while being inclined at such inclination angles that the first fitting control grooves  33  on the fitting control lever  30  intersect the second fitting control grooves  35  at the end portions which are spaced far away from the first mounting initiating position P1. Therefore, as the fitting control lever  30  is pulled out progressively, the first lever engagement shaft portions  12  on the first fitting control grooves  33  are moved towards the second lever engagement shaft portions  22  on the second fitting control grooves  35 , whereby both the connector housings are getting fitted deeply together. 
     Then, when the fitting control lever  30  is pulled out of both the connector housings as shown in  FIG. 10 , the connector housings are fitted together completely and at the same time, the fitting control lever  30  is disengaged from both the connector housings. In addition, when both the connector housings are fitted and connected together completely, the locking securing portion  13  of the first connector housing  10  is brought into engagement with the securement ensuring portion  24  of the second connector housing  20 , whereby both the connector housings are locked in the connected state. 
     Namely, the lever-type connector  1  of the first embodiment which has been described heretofore has the configuration in which the connector housings are fitted together deeply in the progressive fashion as the fitting control lever  30  is pulled out. Then, when the connector housings are fitted and connected together completely, the fitting control lever  30  is pulled out of the connector housings and is disengaged from both the connector housings. Because of this, the weight of the fitting control lever  30  is not applied to the connector housings when the connector  1  is in use, thereby making it possible to realize a reduction in weight of the connector  1  when in use. 
     In addition, the fitting control lever  30  can be used to build up another lever-type connector. Because of this, the fitting control lever  30  can be excluded from a set of parts for a normal lever-type connector so that only the first connector housing  10  and the second connector housing  20  have to be prepared therefor, thereby making it possible to realize a reduction in the number of parts involved. 
     Further, in the case of the lever-type connector  1  of the first embodiment, as shown in  FIGS. 4 and 6 , the first boss introduction grooves  32  and the second boss introduction grooves  34  on the fitting control lever  30  are formed on front and rear sides of the lever main bodies  31  so as to be aligned with each other in the direction in which both the connector housings are fitted together. Therefore, the first boss introduction grooves  32  and the second boss introduction grooves  34  can be designed to be disposed the same spacing distance from the same reference plane, thereby making it possible to facilitate the disposition design of the first boss introduction grooves  32  and the second boss introduction grooves  34 . 
     In addition, in the case of the lever-type connector  1  of the first embodiment, when the fitting control lever  30  is mounted on the first connector housing  10 , the first lever engagement shaft portions  12  of the first connector housing  10  are positioned in the first mounting initiating position P1 by the first boss introduction grooves  32 . Further, the positioning portions  37  of the fitting control lever  30  are brought into abutment with the lever temporary securing portions  14  of the first connector housing  10 , whereby the fitting control lever  30  is temporarily fixed to the first connector housing  10 . 
     In other words, since the fitting control lever  30  mounted on the first connector housing  10  is positioned at two locations such as the first boss introduction grooves  32  and the positioning portions  37 , it is possible to ensure a stable positioning of the fitting control lever  30  in which the loosening of the fitting control lever  30  is made difficult to occur. Because of this, when the first connector housing  10  and the second connector housing  20  are registered with their fitting initiating position, the fitting control lever  30  can be prevented from being displaced inadvertently, thereby making it possible to facilitate the registration of the first connector housing  10  and the second connector housing  20  with their fitting initiating position. 
     Consequently, the fitting and connecting of the first connector housing  10  and the second connector housing  20  can be facilitated. 
       FIG. 11  is a side view showing a comparison between a lever-type connector  1 A according to a second embodiment of the invention and the lever-type connector  1  according to the first embodiment. 
     A fitting control lever  30 A of the lever-type connector  1 A according to the second embodiment is such that the fitting control grooves  33  and the second fitting control grooves  35  of the fitting control lever  30  of the first embodiment are changed to first fitting control grooves  33 A and second fitting control grooves  35 A, respectively. The first fitting control grooves  33 A and the second fitting control grooves  35 A of the second embodiment have such curved groove configurations that a moving locus of the fitting control lever  30 A that is formed when the fitting control lever  30 A is pulled out is made into a curve as indicated by an arrow R in  FIG. 11 . 
     In the case of the fitting control lever  30 A of the second embodiment, when the fitting control lever  30 A is pulled out from both the connector housings, a displacement of the fitting control lever  30 A in a direction in which both the connector housings are fitted together is shortened by a distance L2 shown in  FIG. 11  compared with the case of the first embodiment in which the moving locus of the fitting control lever  30  becomes rectilinear. Because of this, a working space necessary to pull out the fitting control lever  30 A can be reduced, thereby making it possible to realize a highly compact mounting of the lever-type connector. 
     It should be noted that the invention is not limited to the embodiments that have been described heretofore and hence can be modified or improved as required. Additionally, the materials, shapes, dimensions, numbers and arrangements of the constituent elements in the respective embodiments are arbitrary and are not limited thereto, provided that the invention can be attained. 
     For example, while the single locking securing portion  13  and the single securement ensuring portion  24  are provided in the embodiments described, a configuration may be adopted in which locking securing portions  13  and securement ensuring portions  24  are each provided in a plurality of locations so that both connector housings are locked in a connected state by a plurality of securing portions. 
     It is apparent that various modifications can be made in the invention within a scope not deviating from the gist of the invention. 
     The present invention is useful for providing a lever-type connector which can realize a reduction in production cost and weight in use by reducing the number of constituent parts involved.