Patent Publication Number: US-6669508-B2

Title: Connector

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a connector with a locking portion for locking a terminal fitting. 
     2. Description of the Related Art 
     Japanese Unexamined Patent Publication No. 6-325814 and FIG. 16 herein both show a known connector. With reference to FIG. 16, the connector has a housing  1  and terminal fittings  2  that are inserted into each of a plurality of cavities  3  arranged transversely at two stages in the housing  1 . Locks  4  are provided at the upper surfaces of the respective cavities  3  and are deformable to enter deformation-permitting spaces  5  above the cavities  3 . Each lock  4  is deformed resiliently and enters the deformation permitting space  5  when the corresponding terminal fitting  2  is inserted into the cavity  3 . The lock  4  is restored resiliently to its original shape when the terminal fitting  2  is inserted to a proper depth. Thus, the lock engages the terminal fitting  2  and locks the terminal fitting  2  in the cavity  3 . 
     A demand has existed in recent years to make connectors smaller. Consideration has been given to meeting this demand by reducing the thickness of the locks  4  and making the deformation permitting spaces  5  smaller in an effort to reduce the interval of the cavities  3 . However, thinner locks  4  are deformed more easily. Thus, the terminal fittings  2  are pulled out of the cavities  3  more easily. Further, a smaller degree of resilient deformation of the locks  4  reduces the engaging areas of the locks  4  with the terminal fittings  2 . This also makes the terminal fittings  2  easier to withdraw from the cavities  3 , and a sufficient locking force cannot be attained. 
     Consideration also has been given to reducing the vertical dimension of the connector by providing the locks at the side surfaces of the cavities and resiliently deforming the locks in a horizontal direction. This necessarily results in a wider connector. 
     In view of the above problems, an object of the present invention is to provide a connector that can be made smaller while ensuring a sufficient locking force of a locking portion for locking a terminal fitting. 
     SUMMARY OF THE INVENTION 
     The invention is directed to a connector with a housing that has a plurality of cavities arranged along an arranging direction. Terminal fittings are insertable into the respective cavities along an inserting direction. At least one lock is formed at the inner surfaces of each cavity and has a locking section configured for engaging the respective terminal fitting. The locks are resiliently deformable in directions oblique to the terminal inserting direction and hence oblique to a direction normal to the inserting direction of the terminal fitting. 
     Each lock extends along the inserting direction of the terminal fittings and has a substantially L-shaped cross section with a first section that extends along the arranging direction of the cavities and a second section that extends along a direction normal thereto. Thus, each L-shaped portion of each lock defines a concave right angle corner that faces into the cavity. 
     Each lock is arranged at a corner of the corresponding cavity and conforms to the shape of the corner. Thus, each lock serves also as a surrounding wall that at least partly surrounds the corresponding cavity. Consequently, the connector can be made smaller as compared to a case where the lock and the deformation permitting space are formed inside a surrounding wall of the cavity. 
     A pair of locks may be provided for each cavity and the locks in each pair may be disposed at adjacent corners of the cavity. Both locks in each pair may have an L-shaped cross-section, with concave corners facing into the corresponding cavity. First sections of the L-shaped locks may be substantially coplanar, and second sections of the L-shaped locks may be substantially parallel to one another and orthogonal to the plane of the first sections. The provision of locks at adjacent corners of each cavity achieves large contact areas and high locking forces even though each lock is small and thin. 
     Each lock may be deformed resiliently in the direction oblique to the arranging direction of the cavities. Thus, dimensions of a necessary deformation permitting space along the vertical and horizontal directions of the housing can be smaller than an amount of resilient deformation of the lock in its deforming direction. As a result, the connector can be made smaller by reducing an arrangement interval of the cavities while ensuring sufficient locking forces for locking the terminal fittings. Additionally the deformation of each lock along a diagonal direction utilizes an area of the housing that normally would be dead space. Thus, space is utilized efficiently. 
     The substantially L-shaped cross section of each lock improves rigidity upon deformation, and a sufficient locking force can be ensured even if the lock is thinned. Therefore, the connector can be made even smaller. 
     Jig insertion openings may be formed at the front of the housing and may be aligned with the respective locks. A jig may be inserted into a jig insertion opening for deflecting the corresponding lock out of engagement with the terminal fitting. Thus, the terminal fitting may be removed for maintenance. Housings that have two locks for each cavity may have a jig insertion opening aligned between the locks in each pair so that a single jig can deflect both locks in the cavity to enable removal of the corresponding terminal fitting. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded section of a connector according to a first embodiment of the present invention. 
     FIG. 2 is an exploded top plan view of the connector partly in section. 
     FIG. 3 is a cross sectional view of the terminal fitting taken along a line perpendicular to the axis of the terminal fitting. 
     FIG. 4 is a front view of a connector housing. 
     FIG. 5 is a front view of a retainer. 
     FIG. 6 is a fragmentary front view of the housing showing a movement of the lock. 
     FIG. 7 is a longitudinal horizontal section showing a state where the lock is deformed resiliently. 
     FIG. 8 is a longitudinal horizontal section showing a state where the lock is engaged with a female terminal fitting. 
     FIG. 9 is a longitudinal vertical section showing a state where the retainer is mounted at a full locking position. 
     FIG. 10 is a longitudinal horizontal section showing the state of FIG.  9 . 
     FIG. 11 is a top plan view, partly in section, of a second embodiment of a connector in accordance with the subject invention. 
     FIG. 12 is a fragmentary front view of the housing of FIG. 11 showing movement of the locks. 
     FIG. 13 is a cross-sectional view of the female terminal fitting taken along a section perpendicular to the axis of the terminal fitting. 
     FIG. 14 is a top plan view, partly in section, of the connector of the second embodiment. 
     FIG. 15 is a top plan view, partly in section and similar to FIG. 14, but showing the locks engaging the terminal fittings and the retainer fully mounted. 
     FIG. 16 is a longitudinal vertical section of a prior art connector. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A connector according to a first embodiment of the invention comprises a female housing  20  with four female terminal fittings  10  and a retainer  40  for holding the female terminal fittings  10  in the female housing  20 , as shown in FIGS. 1-10. The female housing  20  is connectable with a male housing (not shown) provided with male terminal fittings. In the following description, an inserting direction of the female terminal fittings into the female connector housing is referred to as forward direction. 
     Each female terminal fitting  10  is formed by stamping an electrically conductive metallic plate into a specified shape and then bending the stamped plate. The female terminal fitting  10  has opposite front and rear ends, as shown in FIG. 1. A rectangular tube  11  is formed at the front end and is configured for connection with a male tab of the corresponding male terminal fitting. A barrel  12  is formed at the rear end of the female terminal fitting  10  and is configured for connection with an end of a wire W. The barrel  12  includes a wire barrel  13  with two crimping pieces that extend respectively from the left and right sides of a bottom plate thereof. The crimping pieces of the wire barrel  13  are crimped from above into connection with a core of the wire W. The barrel also includes an insulation barrel  14  with two crimping pieces that are crimped from above into connection with an insulated portion of the wire W and with a rubber plug  15  that has been fitted on the insulated portion. 
     The rectangular tube  11  has an open front end and a resilient contact piece inside. The male tab can be inserted through the open front end of the rectangular  11 , and into contact with the resilient contact piece to establish electrical connection. A stabilizer  16  projects from the upper surface of the rectangular tube  11  at the widthwise center of the rear end of the upper surface. Two side portions of the metallic plate are placed one over the other to define the upper wall of the rectangular tube  11 . A recessed engaging portion  17  is formed by cutting off a section of the surrounding wall of the rectangular tube  11  including an upper right corner and upper portions of the adjacent side wall near the center of the rectangular tube  11  with respect to forward and backward directions. 
     The female housing  20  is made of synthetic resin, and has a long narrow terminal-mounting portion  21 . A substantially rectangular tubular receptacle  22  surrounds a front half of the terminal-mounting portion  21 , as shown in FIGS. 1 and 2, and is configured to receive the male connector housing. Cavities  23  are formed inside the terminal mounting portion  21  and are arranged at each of two horizontal stages as shown in FIGS. 1,  2  and  4 . A terminal insertion opening  24  is formed at the rear end of each cavity  23  for receiving the respective female terminal fitting  10 . Portions of each cavity  23  adjacent the terminal insertion opening  24  define a round cross section dimensioned for hermetic sealing engagement with the rubber plug  15 . The front half of each cavity  23  has a substantially rectangular cross section corresponding to the outer shape of the rectangular tube  11 . A guide groove  28  extends in forward and backward directions in the ceiling surface of each cavity  23 . The stabilizer  16  enters the guide groove  28  during insertion of the female terminal fitting  10  to stabilize and orient the terminal fitting  10 . 
     The terminal mounting portion  21  has a rectangular portion  25  that extends between the back surface of the receptacle  22  and a substantially center position of the receptacle  22 . Long narrow projections  26  project forward from the rectangular portion  25  in correspondence with the respective cavities  23 . Each projection  26  covers substantially a bottom half of a front end of the female terminal fitting  10  inserted into each cavity  23 . A front wall  27  is formed at the front end of the projection  26  to define the front end position of the inserted female terminal fitting  10 . The front wall  27  forms a bottom half of an edge of a tab insertion opening through which the male tab of the male terminal fitting is insertable. 
     A lock  29  for locking the female terminal fitting  10  projects from the front end of the rectangular portion  25  above the projection  26  that corresponds to the respective cavity  23 . Each lock  29  projects forward by a distance that is about half the length of the respective projection  26 , and is comprised of an upper wall  29 A that extends along the horizontal direction of the female connector housing  20  and a side wall  29 B that extends along the vertical direction thereof. Thus, each lock  29  has a substantially L-shaped cross section, as shown in FIG.  3  and defines a concave corner that faces inwardly. Further, each lock  29  is arranged at the upper right corner of the corresponding cavity  23  when viewed from front and conforms to the shape of the corner. 
     A locking section  31  projects at the leading end of each lock  29  and is engageable with the engaging portion  17  of the corresponding female terminal fitting  10 . More specifically, the locking section  31  projects toward the inside of the cavity  23  from an area including a corner portion  29 C (see upper right position of FIG. 6) of the lock  29 , and is comprised integrally of a downward projection  31 A that projects down from the upper wall  29 A of the lock  29  and a lateral projection  31 B that projects leftward from the side wall  29 B, to define an L-shaped cross section. Moderately sloped surfaces are formed on rear sides of the projections  31 A,  31 B, and the front surfaces of the two projections  31 A,  31 B align with the front end surface of the lock  29 . The lock  29  is formed to be thin and resiliently deformable in an upper-right direction when viewed from front (direction indicated by an arrow of FIG.  6 ). 
     The retainer  40  is made of a synthetic resin and defines a substantially rectangular parallelepipedic shape, as shown in FIGS. 1 and 4. Through holes  41  penetrate the retainer  40  in forward and backward directions at positions corresponding to the respective cavities  23 . The retainer  40  is mountable on the front side of the rectangular portion  25  so that the projections  26  fit into the through holes  41 . A front wall  42  is formed at the upper part of the front end of each through hole  41  and forms an upper half of the edge of the tab insertion opening through which the male tab is insertable. More particularly, the front wall  42  of the retainer  40  is aligned with the front wall  27  of the corresponding projection  26  when the retainer  40  is mounted at a full locking position in the female housing  20 . A deformation preventing portion  44  is formed on the inner wall of each through hole  41  and can be disposed along the outer side surface of the side wall  29 B of the lock  29  to prevent deformation of the lock  29 . The retainer  40  can be held at two positions by an unillustrated positioning means, namely, a full locking position (see FIG. 7) where the deformation preventing portions  44  prevent the deformation of the locks  29  and a partial locking position (see FIG. 5) where the deformation preventing portions  44  are retracted forward from the full locking position to permit the deformation of the locks  29 . Jig insertion openings  45  penetrate the front surface of the retainer  40  at positions above the respective front walls  42 , and a jig (not shown) is insertable through the jig insertion openings  45  to disengage the locks  29 . 
     The connector is assembled by first holding the retainer  40  at the partial locking position shown in FIGS. 7 and 8. The female terminal fittings  10  then are inserted into the cavities  23  through the terminal insertion openings  24 . The leading end of each rectangular tube  11  contacts the locking section  31  of the corresponding lock  29  and the lock  29  is deformed resiliently in an oblique direction, i.e. the upper right direction in FIG.  7  and the direction indicated by the arrow in FIG.  6 . More particularly, the lock  29  is pushed up and to the right along the slanted surfaces of the downward projection  31 A and the downward projection  31 B. 
     The female terminal fitting  10  eventually reaches a proper position and contacts the front wall  27 . The lock  29  then is restored resiliently to its original shape and the locking section  31  enters the engaging portion  17 , as shown in FIG.  8 . As a result, the female terminal fitting  10  is locked partially. 
     The retainer  40  is pushed back and is held at the full locking position, as shown in FIG. 9, after the female terminal fittings are mounted in the cavities  23 . Thus, the deformation preventing portions  44  are along the outer surfaces of the side walls  29 B of the respective locks  29  to prevent deformation of the locks  29  and to lock the female terminal fittings  10  doubly. In this way, the assembling of the female connector is completed. 
     If any of the female terminal fittings  10  erroneously is inserted only partly during the above operation process, the opening edge of the through hole  41  contacts the leading end of the lock  29  to prevent movement of the retainer  40  when an attempt is made to move the retainer  40  to the full locking position. Thus, an operator can notice an insufficient insertion of the female terminal fitting  10 . 
     As described above, according to this embodiment, the lock  29  has a substantially L-shaped cross section with two sides that extend respectively along the arranging direction of the cavities  23  and a direction normal thereto, i.e. vertical and horizontal directions. Thus, the entire lock  29  has an improved rigidity, and a sufficient locking force for locking the female terminal fitting  10  can be ensured even if the lock  29  is thinned. Therefore, the connector can be made even smaller with respect to vertical and horizontal directions of the housing  20 . Further, the locking section  31  is provided in the rigid corner  29 C. Therefore, a large locking force can be attained as compared to a case where a locking section is at another part (e.g. side end of the upper wall opposite from the corner portion) of the lock, and the lock  29  can be made even thinner. 
     The locks  29  are deformed in the directions oblique to the arranging direction (vertical or horizontal direction) of the cavities  23 . Therefore, dimensions of a necessary deformation permitting space along the vertical and horizontal directions of the housing  20  can be smaller than an amount of resilient deformation of the locks  29  in their deforming direction. Thus, the connector can be made smaller by reducing the arrangement interval of the cavities  23  while ensuring sufficient locking forces for locking the female terminal fittings  10 . 
     A dead space generally exists in an area of the surrounding wall around the cavity in a direction diagonal to the cavity. In this embodiment, the lock  29  has a substantially L-shaped cross section at the corner of the cavity and conforms to the shape of this corner. Thus, the lock  29  can be deformed in the diagonal direction and, therefore, space can be used efficiently. 
     Further, the locking section  31  engages the female terminal fitting  10  in two directions normal to each other. Thus, an improved locking force can be attained as compared to the conventional locking portion that engages the terminal fitting from one side. 
     A second embodiment of the connector of the subject invention is illustrated in FIGS. 11-15. The connector of FIGS. 11-15 has several components that are structurally and functionally similar to components described and illustrated with respect to the embodiment of FIGS. 1-10. These similar components are not described again and are identified by the same reference numerals. 
     The connector of FIGS. 11-15 comprises a housing  50  with four female terminal fittings  60 . Each female terminal fitting  60  is similar to the female terminal fittings  10  of the first embodiment, and includes a rectangular tube  11 . However, a recessed engaging portion  61  is formed by cutting off sections, including the upper left and upper right corners and about half of the left and right side walls at locations about centrally along the length of the rectangular tube  11 . 
     The housing  50  of the second embodiment is similar to the housing  20  of the first embodiment. In particular, the housing  50  has a terminal mounting portion  21  and a receptacle  22  that surrounds and is spaced from a rectangular front section  25  of the terminal accommodating portion  21 . The terminal accommodating portion  21  has four cavities  23  for receiving the terminal fittings  60 . 
     The housing  50  has two locks  51  for each cavity  23 . The locks  51  project from the front end of the rectangular portion  25  above the projecting portion  26  and are configured for locking the female terminal fittings  60  in the respective cavities  23 . Each lock  51  projects forward by a distance about half the length of the projecting portions  26 , and is comprised of an upper wall  51 A that extends along the horizontal direction of the female connector housing  50  and a side wall  51 B that extends along the vertical direction thereof. Thus, each lock  51  has a substantially L-shaped cross section. Further, the locks  51  for each cavity  23  are arranged at adjacent upper corners of the cavity  23  and conform to the shapes of the corners. Locking sections  52  project from the leading ends of the locks  51  for engaging the female terminal fittings  60 . More specifically, each locking section  52  projects toward the inside of the cavity  23  from an area including a corner  51 C of the lock  51  (see upper-right position of FIG. 12) and is integrally comprised of a downward projection  52 A that projects down from the upper wall  51 A of the lock  51  and a lateral projection  52 B that projects laterally from the side wall  51 B. Thus, each locking section  52  has an L-shaped cross section that is concave towards the interior of the respective cavity  23 . Each lock  51  is thin and is resiliently deformable in an oblique upward direction to depart from each other (see arrows of FIG.  12 ). 
     The female terminal fittings  60  are mounted into the female connector housing  50  with the retainer  40  held at the partial locking position before the rectangular portion  25 , as shown in FIG.  14 . More particularly, the female terminal fitting  60  is inserted into the cavity  23  from the rear through the terminal insertion opening  24 . The locks  51  of each pair deform obliquely up and away from each other as shown in FIG.  14  and by arrows of FIG. 12 when the leading end of the rectangular tube  11  moves along the slanted surfaces of the downward projections  52 A and the lateral projections  52 B. 
     The locks  52  are restored resiliently to their original shapes when the female terminal fitting  60  reaches a proper position and contacts the front wall  27 . Thus, the locking sections  52  enter the engaging portion  61 , as shown in FIG. 15, to achieve partial locking of the female terminal fitting  60 . 
     The retainer  40  is pushed back to the full locking position after the female terminal fittings  60  are mounted into all the cavities  23 . The deformation preventing portions  44  then become located along the outer side surfaces of the side walls  51 B of the respective locks  51 , and thereby prevent the resilient deformation of the locks  51 . As a result, the female terminal fittings  60  are locked doubly. In this way, the assembling of the female connector is completed. 
     If any of the female terminal fittings  60  erroneously is left partly inserted, the opening edge of the through hole  41  of the retainer  40  contacts the leading ends of the locks  60  to prevent movement of the retainer  40  to the full locking position. Thus, an operator can notice an insufficient insertion of the female terminal fitting  60 . 
     The female terminal fitting  60  is detached by returning the retainer  40  to the partial locking position. The leading end of a disengaging jig J then is inserted through the jig insertion opening  45  of the retainer  40  and into the jig inserting space  32  between the pair of locks  51 . The locks  51  then are pushed horizontally away from each other and are deformed obliquely up to disengage the locking sections  52 . The female terminal fitting  60  then is withdrawn from the cavity  23  by pulling back on the wire W. 
     The connector of the second embodiment achieves the same advantages and effects as the first embodiment. However, more secure locking forces can be achieved because two locks  51  engage each terminal fitting  60 . Additionally engagement is achieved at opposite sides of the terminal fitting  60  and hence locking forces on each terminal fitting  60  are balance. Furthermore each terminal fitting  60  is locked from both sides and the top. Hence, locking forces are more secure. 
     Furthermore, the pair of locks  51  can be disengaged at once by inserting the disengaging jig J into the jig inserting space  32  between the locks  51  in the respective pair. Therefore, the locks  51  can be disengaged easily from the female terminal fitting  60 . 
     The present invention is not limited to the above described and illustrated embodiment. For example, following embodiments are also embraced by the technical scope of the present invention. Beside the following embodiments, various changes can be made without departing from the scope and spirit of the present invention. 
     The present invention is also applicable to male connectors provided with male terminal fittings. 
     The cross section of the lock could not be L-shaped. For example, the lock may merely define a corner portion or triangle to lock a corresponding corner of the terminal fitting an/or edge regions near the corner of the terminal fitting. 
     The lock may be formed inside the surrounding wall of the cavity.