Abstract:
A joint connector has a housing ( 10 ) with insertion spaces ( 11 ) for receiving terminal fittings ( 20 ). A joint terminal ( 30 ) is mounted in the housing ( 10 ) at a first position where the joint terminal ( 30 ) is retracted from the insertion spaces ( 11 ). The terminal fittings ( 20 ) then are inserted into the insertion spaces ( 11 ) of the housing ( 10 ). The joint terminal ( 30 ) then is displaced to a full locking position for contacting and shorting the terminal fittings ( 20 ). As a result, the joint terminal ( 30 ) does not hinder insertion of the terminal fittings ( 20 ). Furthermore, the joint terminal ( 30 ) is mounted directly in the housing ( 10 ) and does not require a separate holder. Thus, the number of parts is reduced.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The invention relates to a joint connector and to a method of assembling it.  
         [0003]     2. Description of the Related Art  
         [0004]     U.S. Pat. No. 6,878,017 discloses a joint connector that has a housing and a plurality of terminal fittings mounted in the housing. A joint terminal is mounted in a holder and has a plurality of contact portions. The contact portions can be brought into contact with the terminal fittings in the housing to short the terminal fittings.  
         [0005]     The number of parts of the joint connector could be reduced by eliminating the holder and mounting the joint terminal in the housing. However, a connection resistance is produced between the joint terminal and the terminal fittings when the terminal fittings are inserted into the housing and creates a reaction force against the insertion. The terminal fittings often are inserted into the housing by gripping wires connected with the terminal fittings. However, the above-described connection resistance causes the wires to buckle, thereby making it impossible to insert the terminal fittings.  
         [0006]     The invention was developed in view of the above problem and an object thereof is to reduce the number of parts without hindering the insertion of terminal fittings into a housing.  
       SUMMARY OF THE INVENTION  
       [0007]     The invention relates to a joint connector that has a housing with insertion spaces fro receiving terminal fittings. The joint connector also has a joint terminal for contacting and shorting the terminal fittings. The joint terminal is mounted at a first position in the housing where the joint terminal is retracted from the insertion spaces for the terminal fittings. However, the joint terminal can be moved to a second position in the housing where the joint terminal enters the insertion spaces and contacts the terminal fittings.  
         [0008]     The joint terminal is held at the first position while the terminal fittings are being inserted into the housing. Thus, the joint terminal does not significantly resist insertion of the terminal fittings. The joint terminal is moved to the second position after the terminal fittings have been inserted into the housing. Thus, the joint terminal contacts and shorts the terminal fittings in the housing. The joint terminal is mounted in the housing without a separate holder. As a result, the number of parts can be reduced.  
         [0009]     Leading ends of contacts of the joint terminal may fit in the leading ends of the terminal fittings when the joint terminal is at the first position. Thus, the contacts will not collide with the terminal fittings as the joint terminal is displaced to the second position.  
         [0010]     The joint terminal may lightly touch resilient contacts of the terminal fitting when the joint terminal is at the first position. However, such contact preferably does not deform the resilient contact piece significantly.  
         [0011]     The resilient contacts of the terminal fitting preferably are deformed maximally when the joint terminal is at the second position.  
         [0012]     The joint terminal preferably has a wide rectangular main portion and long contacts that extend from an edge of the main portion. The contacts preferably are continuous and substantially flush with the main portion.  
         [0013]     Locking pieces preferably project out and forward from a plane that contains the main portion and the contacts. The locking pieces engage the housing to prevent movement of the joint terminal towards the second position. First projections preferably project out from the main portion substantially in the plane containing the main portion and the contacts. The first projections engage the housing to prevent movement of the joint terminal from the housing.  
         [0014]     The invention also relates to a method of assembling a joint connector. The method comprises providing a housing with insertion spaces for accommodating terminal fittings. The method proceeds by mounting a joint terminal at a first position in the housing so that the joint terminal does not project significantly into the insertion spaces for the terminal fittings. The method then includes mounting the terminal fittings in the insertion spaces and moving the joint terminal to a second position for shorting contact with the terminal fittings in the insertion spaces.  
         [0015]     These and other objects, features and advantages of the present invention will become more apparent upon reading of the following detailed description of preferred embodiments and accompanying drawings. It should be understood that even though embodiments are separately described, single features thereof may be combined to additional embodiments. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]      FIG. 1  is a longitudinal section of a housing of the invention with a terminal fitting in the housing and a joint terminal detached from the housing.  
         [0017]      FIG. 2  is a front view of the housing.  
         [0018]      FIG. 3  is a partial enlarged horizontal section showing a state where the joint terminal is at a partial locking position.  
         [0019]      FIG. 4  is a partial enlarged longitudinal section showing a state where the terminal fittings are inserted while the joint terminal is at the partial locking position.  
         [0020]      FIG. 5  is a partial enlarged horizontal section showing the joint terminal at a full locking position.  
         [0021]      FIG. 6  is a partial enlarged longitudinal section showing the joint terminal at the full locking position.  
         [0022]      FIG. 7  is a plan view of the joint terminal.  
         [0023]      FIG. 8  is a side view of the joint terminal. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0024]     A joint connector according to the invention has a housing identified by the numeral  10  in FIGS.  1  to  6 . The housing  10  is made e.g. of a synthetic resin and is substantially in the form of a flat block with opposite front and rear ends. Long narrow cavities  11  extend through the housing  10  in forward and backward directions and are arranged substantially side by side along a transverse direction TD. A terminal insertion opening  12  extends into each cavity  11  at the rear end of the housing  10 . Locks  13  are formed unitarily with the housing  10  and are cantilevered forward along the bottom wall of the respective cavities  11 . Each lock  13  is resiliently deformable up and down towards and away from the respective cavity  11 .  
         [0025]     A wide slit-shaped guiding groove  14  is formed in the front end surface of the housing  10  and extends across a transverse area corresponding to the cavities  11 . Upper and lower surfaces of the guiding groove  14  are flat and extend substantially parallel to an inserting direction ID defined by the cavities  11 . A partition wall  15  partitions the guiding groove  14  and the cavities  11 , and guiding holes  16  penetrate the partition wall  15  in substantially forward and backward directions from the rear surface of the guiding groove  14  to the front surfaces of the cavities  11 . Upper and lower surfaces of the guiding holes  16  are substantially continuous and flush with the corresponding surfaces of the guiding groove  14 . A forwardly and upwardly slanted partial-locking surface  17  is formed at the front end of the upper surface of the guiding groove  14 . Step-shaped left and right full locks  18  are formed on the upper surface of the guiding groove  14  at positions behind the slanted partial-locking surface  17  and step-shaped partial locks  19  are formed in the left and right surfaces of the guiding groove  14 .  
         [0026]     The joint connector further includes female terminal fittings  20 . Each terminal fitting  20  is long and narrow in forward and backward directions and has opposite front and rear ends. A tubular fitting  21  is formed at the front end of each terminal fitting  20 , and the interior of the tubular fitting  21  is open at the front end. A resilient contact piece  22  is provided in the tubular fitting  21 , and a locking hole  23  is formed in the bottom wall of the tubular fitting  21  for engaging a retaining projection  13   a  of the lock  13 . A wire connecting portion  24  is formed at the rear end of the terminal fitting  20  and is configured to be crimped, bent or folded into connection with a wire  25 . The connected wire  25  extends back from the terminal fitting. The terminal fitting  20  is configured to be inserted into the cavity  11  from behind and along the inserting direction ID.  
         [0027]     The joint terminal  30  is made of a substantially flat conductive metal sheet stamped or cut out into a specified shape. More particularly, the joint terminal  30  has a substantially rectangular main portion  31  that is wide in the transverse direction TD. Long narrow contacts  32  extend back in an extending direction ED from a rear edge of the main portion  31 . The contacts  32  are continuous and substantially flush with the main portion  31 . The front edge of the main portion  31  is cut and bent to form left and right locks  33  that rise obliquely up to the front and out of the plane that contains the main portion  31  and the contacts  32 . Left and right partial locks  34  project out from the opposite left and right edges of the main portion  31  substantially in the plane of the main portion  31  and the contacts  32 .  
         [0028]     The joint terminal  30  is mounted in the housing  10  before the terminal fittings  20  are inserted into the housing  10 . More particularly, the joint terminal  30  is inserted into the guiding groove  14  from the front and along a mounting direction MD and is left at a partial locking position  1 P. The main portion  31  is at a front area in the guiding groove  14  and the rear ends of the respective contacts  32  project slightly into the cavities  11  through the guiding holes  16  when the joint terminal  30  is at the partial locking position  1 P. The guiding groove  14  prevents displacements of the main portion  31  along the vertical direction and the transverse direction TD. Additionally, guiding holes  16  prevent displacements of the contacts  32  along the vertical direction and the transverse direction TD. Further, the locking pieces  33  engage the slanted partial-locking surface  17  from the front to prevent backward displacement of the joint terminal  30  in the mounting direction MD. Still further, the partial locking projections  34  engage the partial locks  19  from behind to prevent movement of the joint terminal  30  opposite to the mounting direction MD. In this way, the joint terminal  30  is held at the partial locking position  1 P.  
         [0029]     The joint terminal  30  can be moved from the partial locking position  1 P to a full locking position  2 P by pushing the main portion  31  from the front and along the mounting direction MD. The contacts  32  extend farther into the cavities  11  when the joint terminal  30  is moved to the full locking position  2 P than when the joint terminal  30  is at the partial locking position  1 P. Further, backward movement of the joint terminal  30  is prevented by the contact of the rear edge of the main portion  31  with the front end surface of the partition wall  15 , and a forward returning movement of the joint terminal  30  towards the partial locking position  1  P is prevented by the engagement of the left and right locking pieces  33  with the full locking portions  18  from behind. As a result, the joint terminal  30  can be held at the full locking position  2 P.  
         [0030]     The joint terminal  30  is mounted into the housing  10  from the front and along the mounting direction MD. As a result, the joint terminal  30  is held at the partial locking position  1 P. The terminal fittings  20  then are inserted into the corresponding cavities  11  from behind and along the inserting direction ID. In the inserting process, the tubular fitting  21  contacts the retaining projection  13   a  to deform the lock  13  down and out. The lock  13  resiliently returns when the terminal fitting  20  reaches a properly inserted state so that the retaining projection  13   a  engages the locking hole  23 . As a result, the terminal fitting  20  is retained. When the terminal fitting  20  is inserted properly, the leading end of the corresponding contact  32  of the joint terminal  30  is fit lightly in the tubular fitting  21 . At this time, the contact  32  lightly touches the resilient contact piece  22  to an extent that hardly deforms the resilient contact piece  22 .  
         [0031]     The joint terminal  30  is pushed substantially in the extending direction ED from the partial locking position  1 P to the full locking position  2 P after all of the terminal fittings  20  are inserted. The contacts  32  slide in contact with the lower surfaces of the resilient contact pieces  22  during the pushing process and gradually deform the resilient contact pieces  22 . The resilient contact pieces  22  are deformed maximally when the joint terminal  30  reaches the full locking position  2 P. As a result, the contacts  32  and the resilient contact pieces  22  are connected electrically with contact pressures resulting from resilient restoring forces of the resilient contact pieces  22 . In this way, the terminal fittings  20  are shorted by the joint terminal  30 .  
         [0032]     The joint terminal  30  is mounted into the housing  10  in the embodiment described above. However, it is not necessary to provide means for holding the joint terminal  30  in addition to the housing  10 , thereby reducing the number of parts.  
         [0033]     Further, the joint terminal  30  mounted in the housing  10  is displaceable between the full locking position  2 P where the joint terminal  30  enters the cavities  11  and the partial locking position  1 P where the joint terminal  30  is retracted forwardly from the cavities  11 . Accordingly, insertion of the terminal fittings  20  into the housing  10  creates substantially no insertion resistance by the contact of the joint terminal  30  and the terminal fittings  20  when the joint terminal  30  is at the partial locking position  1 P. Therefore, there is no likelihood of hindering the insertion of the terminal fittings  20 .  
         [0034]     The leading ends of the contacts  32  of the joint terminal  30  are fit in the leading ends of the terminal fittings  20  with the joint terminal  30  held at the partial locking position  1 P. Thus, the contact portions  32  can enter the tubular fittings  21  and can be connected without colliding with the terminal fittings  20  when the joint terminal  30  is displaced to the full locking position  2 P.  
         [0035]     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.  
         [0036]     The terminal fittings are female terminal fittings in the foregoing embodiment. However, the invention is also applicable to male terminal fittings.  
         [0037]     The number of the terminal fittings (number of contacts) is four in the foregoing embodiment. However, it may be two, three, five or more.  
         [0038]     The contacts of the joint terminal contact the terminal fittings with the joint terminal held at the partial locking position in the foregoing embodiment. However, the joint terminal need not contact the terminal fittings when the joint terminal is at the partial locking position.