Patent Publication Number: US-9431760-B2

Title: Electrical connector capable of connecting a plurality of electric wires to a connection object

Description:
INCORPORATION BY REFERENCE 
     This application is based upon and claims the benefit of priority from Japanese patent application No. 2014-071467, filed on Mar. 31, 2014, the disclosure of which is incorporated herein in its entirety by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an electric connector, a connection object unit, and a connection object unit assembly. 
     2. Description of Related Art 
     Japanese Patent No. 5352723 discloses a plug connector  102  and a receptacle connector  103  which are used to connect a connection cable  101  to a battery  100  as shown in  FIG. 22  of this application. The plug connector  102  is attached to an end of the connection cable  101 . The receptacle connector  103  is attached to a battery post  106  with a nut  107 . The battery post  106  has an external thread shape and projects from an upper surface  105  of a battery body  104  of the battery  100 . The receptacle connector  103  includes a receptacle contact  109  and a receptacle housing  110 . The receptacle contact  109  has a bolt hole  108  formed therein for bolt-fastening. In the above structure, when the plug connector  102  is mated with the receptacle connector  103 , the connection cable  101  is connected to the battery  100 . 
     Incidentally, there is a demand for simultaneously connecting a plurality of connection cables  101  to the battery post  106  of the battery  100 . There is also a demand for further downsizing of the receptacle connector  103 . 
     It is an object of the present invention to provide a technique for downsizing an electric connector capable of connecting a plurality of electric wires to a connection object. 
     SUMMARY OF THE INVENTION 
     A first exemplary aspect of the present invention is an electric connector that is attached to a connection object, is mated with a first connector attached to a first electric wire to thereby electrically connect the first electric wire to the connection object, and is mated with a second connector attached to a second electric wire to thereby electrically connect the second electric wire to the connection object, the electric connector including: a contact; and a housing that is attached to the contact, the housing including: a first retaining portion that prevents the first connector mated with the electric connector from being disengaged from the electric connector; and a second retaining portion that prevents the second connector mated with the electric connector from being disengaged from the electric connector. The contact includes: a first contact portion having a flat plate shape and capable of being in electrical contact with the first connector; a second contact portion having a flat plate shape and capable of being in electrical contact with the second connector; and a third contact portion having a flat plate shape and capable of being in electrical contact with the connection object. A thickness direction of the first contact portion and a thickness direction of the second contact portion are substantially perpendicular to a thickness direction of the third contact portion. A direction in which the first connector is mated with the electric connector is different from a direction in which the second connector is mated with the electric connector. 
     A second exemplary aspect of the present invention is a connection object unit including a connection object and a connector assembly including: a first connector attached to a first electric wire; a second connector attached to a second electric wire; and an electric connector that is attached to the connection object, is mated with the first connector to thereby electrically connect the first electric wire to the connection object, and is mated with the second connector to thereby electrically connect the second electric wire to the connection object. The electric connector includes a contact and a housing that is attached to the contact, the housing including: a first retaining portion that prevents the first connector mated with the electric connector from being disengaged from the electric connector; and a second retaining portion that prevents the second connector mated with the electric connector from being disengaged from the electric connector. The contact includes: a first contact portion having a flat plate shape and capable of being in electrical contact with the first connector; a second contact portion having a flat plate shape and capable of being in electrical contact with the second connector; and a third contact portion having a flat plate shape and capable of being in electrical contact with the connection object. A thickness direction of the first contact portion and a thickness direction of the second contact portion are substantially perpendicular to a thickness direction of the third contact portion. A direction in which the first connector is mated with the electric connector is different from a direction in which the second connector is mated with the electric connector. 
     According to exemplary aspects of the present invention, it is possible to downsize an electric connector capable of connecting a plurality of electric wires to a connection object. 
     The above and other objects, features and advantages of the present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not to be considered as limiting the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a connector assembly (first exemplary embodiment); 
         FIG. 2  is a perspective view of a battery to which the connector assembly is attached (first exemplary embodiment); 
         FIG. 3  is a perspective view showing a state in which a plurality of batteries are connected to each other (first exemplary embodiment); 
         FIG. 4  is a perspective view of a pin connector (first exemplary embodiment); 
         FIG. 5  is a partially cutaway perspective view of the pin connector (first exemplary embodiment); 
         FIG. 6  is a partially cutaway perspective view of the pin connector (first exemplary embodiment); 
         FIG. 7  is a perspective view of the pin connector when viewed from another angle (first exemplary embodiment); 
         FIG. 8  is a perspective view of the pin connector when viewed from still another angle (first exemplary embodiment); 
         FIG. 9  is an exploded perspective view of the pin connector (first exemplary embodiment); 
         FIG. 10  is an exploded perspective view of the pin connector (first exemplary embodiment); 
         FIG. 11  is a perspective view of a pin contact (first exemplary embodiment); 
         FIG. 12  is a perspective view of the pin contact when viewed from another angle (first exemplary embodiment); 
         FIG. 13  is a perspective view of an upper housing divided body (first exemplary embodiment); 
         FIG. 14  is a partially cutaway perspective view of the upper housing divided body (first exemplary embodiment); 
         FIG. 15  is a partially cutaway perspective view of the upper housing divided body (first exemplary embodiment); 
         FIG. 16  is a plan view of the pin connector (first exemplary embodiment); 
         FIG. 17  is a partially cutaway perspective view of a socket connector attached to an end of a cable (first exemplary embodiment); 
         FIG. 18  is a partially cutaway perspective view of the socket connector attached to an end of the cable (first exemplary embodiment); 
         FIG. 19  is a perspective view of a pin contact (second exemplary embodiment); 
         FIG. 20  is a perspective view of a pin contact (third exemplary embodiment); 
         FIG. 21  is a perspective view of a pin contact (fourth exemplary embodiment); and 
         FIG. 22  is a view corresponding to FIG. 5 of Japanese Patent No. 5352723. 
     
    
    
     DESCRIPTION OF THE EXEMPLARY EMBODIMENTS 
     First Exemplary Embodiment 
       FIGS. 1 to 3  each show a connector assembly  1 . In a first exemplary embodiment, the connector assembly  1  is used to electrically connect a plurality of batteries  2  (connection object), which are arranged in a predetermined direction, with a plurality of cables  3  as shown in  FIGS. 2 and 3 . 
     As shown in  FIG. 2 , each battery  2  includes a rectangular-parallelepiped-shaped battery body  4  and a pair of electrodes  5 . The battery body  4  includes a rectangular upper surface  4 A (electrode arrangement surface), a front surface  4 B, a back surface  4 C, a lower surface  4 D, and a pair of side surfaces  4 E. The pair of electrodes  5  is formed on the upper surface  4 A of the battery body  4 . The pair of electrodes  5  is disposed on both ends in the longitudinal direction of the upper surface  4 A of the battery body  4 . 
     The terms “battery vertical direction”, “battery width direction”, and “battery front-back direction” will now be defined. The term “battery vertical direction” refers to a direction orthogonal to the upper surface  4 A. The battery vertical direction includes an upward direction and a downward direction. The upward direction is a direction from the lower surface  4 D to the upper surface  4 A, and the downward direction is a direction from the upper surface  4 A to the lower surface  4 D. The term “battery width direction” refers to the longitudinal direction of the upper surface  4 A. The battery width direction includes a battery width center direction and a battery width anti-center direction. In the battery width direction, the battery width center direction is a direction approaching the center in the longitudinal direction of the upper surface  4 A, and the battery width anti-center direction is a direction away from the center in the longitudinal direction of the upper surface  4 A. The term “battery front-back direction” refers to a direction orthogonal to each of the battery vertical direction and the battery width direction. The battery front-back direction includes a battery backward direction and a battery forward direction. The battery backward direction is a direction from the front surface  4 B to the back surface  4 C, and the battery forward direction is a direction from the back surface  4 C to the front surface  4 B. 
     In the first exemplary embodiment, as shown in  FIG. 3 , the plurality of batteries  2  are arranged at a predetermined pitch in the vertical direction by using a battery storage rack or the like. 
     As shown in  FIG. 1 , the connector assembly  1  includes a pin connector  6  (electric connector) and a pair of socket connectors  7 .  FIG. 1  shows a state in which the pair of socket connectors  7  is mated with the pin connector  6 . For convenience of explanation, the socket connector  7  located on an upper side of the pin connector  6  is referred to as an upper socket connector  10  (first connector) and the socket connector  7  located on a lower side of the pin connector  6  is referred to as a lower socket connector  11  (second connector). The cable  3  located on an upper side of the connector assembly  1  is referred to as an upper cable  12  (first electric wire) and the cable  3  located on a lower side of the connector assembly  1  is referred to as a lower cable  13  (second electric wire). 
     As shown in  FIGS. 1 and 2 , the pin connector  6  is a connector attached to one of the pair of electrodes  5 . The upper socket connector  10  is a connector attached to an end of the upper cable  12 . The lower socket connector  11  is a connector attached to an end of the lower cable  13 . When the upper socket connector  10  and the lower socket connector  11  are mated with the pin connector  6 , the upper cable  12  and the lower cable  13  are electrically connected to one of the electrodes  5  of the battery  2  shown in  FIG. 2 . 
     (Pin Connector  6 ) 
     Next, the pin connector  6  will be described with reference to  FIGS. 4 to 16 . 
       FIGS. 4, 7, and 8  each show a perspective view of the pin connector  6  viewed from various directions.  FIGS. 5 and 6  each show a partially cutaway perspective view of the pin connector  6 .  FIGS. 9 and 10  each show an exploded view of the pin connector  6 . As shown in  FIGS. 4 to 10 , the pin connector  6  includes a pin contact  20  (contact), a pin housing  21  (housing), and two screws  22 . The pin housing  21  includes an upper housing divided body  23  (first housing divided body) and a lower housing divided body  24  (second housing divided body) that is located under the upper housing divided body  23 . In the state where the upper housing divided body  23  and the lower housing divided body  24  are made to cover the pin contact  20 , the upper housing divided body  23  and the lower housing divided body  24  are coupled together with the two screws  22 , thereby allowing the pin housing  21  to be attached to the pin contact  20 . 
     (Pin Contact  20 ) 
       FIGS. 11 and 12  each show a perspective view of the pin contact  20  viewed from different directions. As shown in  FIGS. 11 and 12 , the pin contact  20  is formed by bending a metallic plate M having a thickness of about 3 mm. Specifically, the pin contact  20  includes an electrode contact portion  30  (third contact portion), an upper contact portion  31  (first contact portion), and a lower contact portion  32  (second contact portion). 
     The electrode contact portion  30  has a flat plate shape, and the thickness direction of the electrode contact portion  30  is substantially parallel to the battery vertical direction. The electrode contact portion  30  is formed in a rectangular shape elongated in the battery width direction. The electrode contact portion  30  has a mounting hole  33  formed therein for attaching the pin contact  20  to the corresponding electrode  5  of the battery  2 . 
     The upper contact portion  31  has a flat plate shape, and the thickness direction of the upper contact portion  31  is substantially parallel to the battery width direction. In other words, the thickness direction of the upper contact portion  31  is substantially perpendicular to the thickness direction of the electrode contact portion  30 . The upper contact portion  31  is formed so as to project upward from an end of the electrode contact portion  30  on the battery width anti-center direction side. The upper contact portion  31  includes a distal end face  31 A, a pair of side end faces  31 B, and a pair of contact surfaces  31 C. The distal end face  31 A is substantially orthogonal to the battery vertical direction. The pair of side end faces  31 B is substantially orthogonal to the battery front-back direction. The pair of contact surfaces  31 C is substantially orthogonal to the battery width direction. An upper connecting portion  34  (a first connecting portion, a first fold, and a first bent portion) is formed between the upper contact portion  31  and the electrode contact portion  30 . The upper contact portion  31  and the electrode contact portion  30  are connected to each other at the upper connecting portion  34 . The upper connecting portion  34  is a portion where the upper contact portion  31  having a flat plate shape and the electrode contact portion  30  having a flat plate shape are connected to each other, and is thus inevitably formed to have a linear appearance. The upper connecting portion  34  formed to have a linear appearance extends in the battery front-back direction. The upper contact portion  31  has a central axis C 1 . The central axis C 1  is the central axis of the upper contact portion  31  in the direction parallel to the projecting direction of the upper contact portion  31 . 
     The lower contact portion  32  has a flat plate shape, and the thickness direction of the lower contact portion  32  is substantially parallel to the battery width direction. In other words, the thickness direction of the lower contact portion  32  is substantially perpendicular to the thickness direction of the electrode contact portion  30 . The lower contact portion  32  is formed so as to project downward from an end of the electrode contact portion  30  on the battery width anti-center direction side. The lower contact portion  32  includes a distal end face  32 A, a pair of side end faces  32 B, and a pair of contact surfaces  32 C. The distal end face  32 A is substantially orthogonal to the battery vertical direction. The pair of side end faces  32 B is substantially orthogonal to the battery front-back direction. The pair of contact surfaces  32 C is substantially orthogonal to the battery width direction. A lower connecting portion  35  (a second connecting portion, a second fold, and a second bent portion) is formed between the lower contact portion  32  and the electrode contact portion  30 . The lower contact portion  32  and the electrode contact portion  30  are connected to each other at the lower connecting portion  35 . The lower connecting portion  35  is a portion where the lower contact portion  32  having a flat plate shape and the electrode contact portion  30  having a flat plate shape are connected to each other, and is thus inevitably formed to have a linear appearance. The lower connecting portion  35  formed to have a linear appearance extends in the battery front-back direction. The lower contact portion  32  has a central axis C 2 . The central axis C 2  is the central axis of the lower contact portion  32  in the direction parallel to the projecting direction of the lower contact portion  32 . 
     In the first exemplary embodiment, the upper contact portion  31  and the lower contact portion  32  are disposed at different locations in the battery front-back direction. In other words, the central axis C 1  of the upper contact portion  31  does not coincide with a virtual extension Q of the central axis C 2  of the lower contact portion  32 . Specifically, the upper contact portion  31  is located on the battery backward direction side relative to the lower contact portion  32 . 
     The upper contact portion  31  and the lower contact portion  32  are disposed at the same location in the battery width direction. 
     The upper contact portion  31  and the lower contact portion  32  are disposed at different locations in the battery vertical direction. Specifically, the upper contact portion  31  is located on an upper side relative to the lower contact portion  32 . In other words, the direction in which the upper contact portion  31  projects from the electrode contact portion  30  is opposite to the direction in which the lower contact portion  32  projects from the electrode contact portion  30 . 
     The thickness direction of the upper contact portion  31  and the thickness direction of the lower contact portion  32  are substantially parallel to each other. 
     (Upper Housing Divided Body  23 ) 
     In the first exemplary embodiment, the upper housing divided body  23  and the lower housing divided body  24  have the same shape. As shown in  FIG. 4 , the lower housing divided body  24  is located in a position where the upper housing divided body  23  is rotated by 180 degrees about the axis of rotation parallel to the battery width direction. Accordingly, only the upper housing divided body  23  will be described below, and the description of the lower housing divided body  24  will be omitted.  FIGS. 13 to 15  each show a perspective view of the upper housing divided body  23 . 
     As shown in  FIGS. 13 to 15 , the upper housing divided body  23  includes a base  40  having a flat plate shape, an inner cover portion  41  (first inner cover portion), and an outer cover portion  42  (first outer cover portion). 
     The base  40  has a flat plate shape, and the thickness direction of the base  40  is substantially parallel to the battery vertical direction. The base  40  is formed in a rectangular shape elongated in the battery front-back direction. The base  40  includes a cover support portion  43  which is located on the battery backward direction side, and a connecting portion covering portion  44  (first connecting portion covering portion) which is located on the battery forward direction side. As shown in  FIG. 15 , the cover support portion  43  has an insertion hole  45  into which the upper contact portion  31  of the pin contact  20  shown in  FIG. 11  can be inserted in the upward direction. As shown in  FIGS. 13 and 14 , the connecting portion covering portion  44  has a screw hole  46  formed therein for coupling the upper housing divided body  23  and the lower housing divided body  24  with the screw  22 . 
     As shown in  FIG. 14 , the inner cover portion  41  is formed so as to project upward from the cover support portion  43 . The inner cover portion  41  includes a distal end face covering portion  47 , a pair of side end face covering portions  48 , and a pair of reinforcement beam portions  49 . The distal end face covering portion  47  is a beam that covers the distal end face  31 A of the upper contact portion  31  of the pin contact  20  shown in  FIG. 11 . The distal end face covering portion  47  extends along the distal end face  31 A shown in  FIG. 11 . In other words, the distal end face covering portion  47  extends in the battery front-back direction. Each one of the pair of side end face covering portions  48  is a beam that covers a corresponding one of the pair of side end faces  31 B of the upper contact portion  31  of the pin contact  20  shown in  FIG. 11 . Each one of the pair of side end face covering portions  48  extends along a corresponding one of the pair of side end faces  31 B shown in  FIG. 11 . In other words, the pair of side end face covering portions  48  extends in the battery vertical direction. Specifically, the pair of side end face covering portions  48  projects upward from the cover support portion  43  of the base  40 , and extends to both ends of the distal end face covering portion  47 . Each one of the pair of reinforcement beam portions  49  is a beam for reinforcing the distal end face covering portion  47 . Each one of the pair of reinforcement beam portions  49  extends along a corresponding one of the pair of contact surfaces  31 C shown in  FIG. 11 . In other words, the pair of reinforcement beam portions  49  extends in the battery vertical direction. Specifically, the pair of reinforcement beam portions  49  projects upward from the cover support portion  43  of the base  40 , and extends to the center in the longitudinal direction of the distal end face covering portion  47 . In the above structure, a contact portion insertion space  50  in which the upper contact portion  31  of the pin contact  20  shown in  FIG. 11  is inserted is formed at the inside of the inner cover portion  41 . 
     As shown in  FIGS. 13 and 15 , the outer cover portion  42  is disposed outside the inner cover portion  41  and forms a connector insertion space  51  in which the upper socket connector  10  shown in  FIG. 1  is inserted. As shown in  FIGS. 13 and 15 , the outer cover portion  42  is formed to have a square tube shape extending in the battery vertical direction. As shown in  FIGS. 13 to 15 , the outer cover portion  42  is formed so as to project upward from the cover support portion  43 . As shown in  FIG. 13 , the outer cover portion  42  is formed in a flat shape. Specifically, the dimension of the outer cover portion  42  in the battery width direction is smaller than the dimension of the outer cover portion  42  in the battery front-back direction. The outer cover portion  42  includes a pair of large side walls  52  and a pair of small side walls  53  (side walls). The large side walls  52  are opposed to each other in the battery width direction, and the small side walls  53  are opposed to each other in the battery front-back direction. The pair of large side walls  52  defines the connector insertion space  51  in the battery width direction. The pair of small side walls  53  defines the connector insertion space  51  in the battery front-back direction. Each one of the pair of small side walls  53  is a side wall opposed to a corresponding one of the pair of side end faces  31 B shown in  FIG. 11 . In other words, the small side wall  53  located on the battery backward direction side is a side wall located on the side opposite to the side end face  31 B located on the battery forward direction side across the side end face  31 B located on the battery backward direction side. The small side wall  53  located on the battery forward direction side is a side wall located on the side opposite to the side end face  31 B located on the battery backward direction side across the side end face  31 B located on the battery forward direction side. Each one of a pair of pin-side lock portions  54  is formed on a corresponding one of the pair of small side walls  53 . Each one of the pair of pin-side lock portions  54  is a portion that prevents the upper socket connector  10  mated with the pin connector  6  from being disengaged from the pin connector  6 . Each one of the pair of pin-side lock portions  54  is formed on a corresponding one of the pair of small side walls  53 , instead of being formed on a corresponding one of the pair of large side walls  52 , thereby suppressing a dimension W in the battery width direction of the outer cover portion  42  as shown in  FIG. 16 . 
     As shown in  FIG. 13 , the upper housing divided body  23  further includes a reinforcement rib  55 . The reinforcement rib  55  is formed between the outer cover portion  42  and the connecting portion covering portion  44 . 
     (Assembly of the Pin Connector  6 ) 
     A method for assembling the pin connector  6  will be described below. As shown in  FIGS. 9 and 10 , the upper contact portion  31  of the pin contact  20  is inserted into the insertion hole  45  of the upper housing divided body  23  and the lower contact portion  32  of the pin contact  20  is inserted into the insertion hole  45  of the lower housing divided body  24 , so that the upper housing divided body  23  and the lower housing divided body  24  can be coupled together with the pair of screws  22 . After the coupling, as shown in  FIGS. 5 and 6 , the upper contact portion  31  of the pin contact  20  is partially exposed from the inner cover portion  41  of the upper housing divided body  23 . Similarly, the lower contact portion  32  of the pin contact  20  is partially exposed from the inner cover portion  41  of the lower housing divided body  24 . 
     (Upper Socket Connector  10 ) 
     In the first exemplary embodiment, the upper socket connector  10  and the lower socket connector  11  have the same shape. Accordingly, only the upper socket connector  10  will be described, and the description of the lower socket connector  11  will be omitted.  FIGS. 17 and 18  each show a partially cutaway perspective view of the upper socket connector  10 . 
     As shown in  FIGS. 17 and 18 , the upper socket connector  10  includes a socket contact  60  and a socket housing  61  that accommodates the socket contact  60 . 
     The socket contact  60  includes a crimp  62 , eight contact spring pieces  63 , and a square-tube-shaped holding portion  64 . The crimp  62  is crimped to the conductor of the upper cable  12 . The holding portion  64  holds the eight contact spring pieces  63 . Four of the contact spring pieces  63  are disposed separately from the other four of the contact spring pieces  63  in the battery width direction. 
     The socket housing  61  includes a housing body  65 , an opening limiting portion  66 , and a pair of socket-side lock portions  67 . The housing body  65  extends in a square tube shape in the battery vertical direction. The opening limiting portion  66  partially blocks an opening  65 A on a lower side of the housing body  65 . The opening limiting portion  66  partially blocks the opening  65 A of the housing body  65 , thereby minimizing the opening area of the opening  65 A of the housing body  65 . The term “minimizing” herein used means that the opening area is limited to a minimum area required to insert the upper contact portion  31  of the pin contact  20  shown in  FIG. 6  and the inner cover portion  41  of the upper housing divided body  23  into the opening  65 A of the housing body  65 . Accordingly, the opening limiting portion  66  includes spring piece opposed portions  66 A that are opposed to the eight contact spring pieces  63  of the socket contact  60  in the battery vertical direction. Each one of the pair of socket-side lock portions  67  is formed to have a claw shape and is supported by the housing body  65  so as to be elastically displaceable in the battery front-back direction. 
     (How to Use the Connector Assembly  1 ) 
     Next, an example of how to use the connector assembly  1  will be described with reference to  FIGS. 1 to 3 . 
     First, the pin connectors  6  are respectively attached to the pair of electrodes  5  of each battery  2 . Next, a plurality of batteries  2  are disposed at a predetermined pitch in the battery vertical direction by using a battery storage rack or the like. Then, the socket connectors  7  are respectively attached to both ends of each cable  3  that is cut at a predetermined length. Lastly, as shown in  FIG. 3 , the pair of socket connectors  7  attached to both ends of the cable  3  is mated with the respective pin connectors  6  of a pair of batteries  2  adjacent to each other in the battery vertical direction, while the cable  3  is slightly warped in the battery front-back direction. Specifically, the lower socket connector  11  attached to an upper end of the cable  3  is inserted upward into the connector insertion space  51  (see  FIG. 13 ) of the lower housing divided body  24  of the pin connector  6  located on an upper side of the cable  3 , and the pair of socket-side lock portions  67  (see  FIG. 17 ) of the lower socket connector  11  is hooked to the pair of pin-side lock portions  54  (see  FIG. 13 ) of the lower housing divided body  24  of the pin connector  6 , thereby mating the lower socket connector  11  with the pin connector  6 . Similarly, the upper socket connector  10  attached to a lower end of the cable  3  is inserted downward into the connector insertion space  51  (see  FIG. 13 ) of the upper housing divided body  23  of the pin connector  6  located on a lower side of the cable  3 , and the pair of socket-side lock portions  67  (see  FIG. 17 ) of the upper socket connector  10  is hooked to the pair of pin-side lock portions  54  (see  FIG. 13 ) of the upper housing divided body  23  of the pin connector  6 , thereby mating the upper socket connector  10  with the pin connector  6 . As a result, the electrodes  5  of the pair of batteries  2  adjacent to each other in the battery vertical direction are electrically connected to each other. More specifically, eight contact spring pieces  63  of the socket contact  60  of the lower socket connector  11  attached to an upper end of the cable  3  are each brought into contact with the pair of contact surfaces  32 C of the lower contact portion  32  of the pin contact  20  of the pin connector  6 . Similarly, eight contact spring pieces  63  of the socket contact  60  of the upper socket connector  10  attached to a lower end of the cable  3  are each brought into contact with the pair of contact surfaces  31 C of the upper contact portion  31  of the pin contact  20  of the pin connector  6 . 
     The connector assembly  1  of the first exemplary embodiment described above has the following features. 
     (1) As shown in  FIGS. 1 to 12 , each pin connector  6  (electric connector) is attached to the corresponding battery  2  (connection object), is mated with the upper socket connector  10  (first connector) attached to the upper cable  12  (first electric wire) to thereby electrically connect the upper cable  12  to the battery  2 , and is mated with the lower socket connector  11  (second connector) attached to the lower cable  13  (second electric wire) to thereby electrically connect the lower cable  13  to the battery  2 . The pin connector  6  includes the pin contact  20  (contact) and the pin housing  21  (housing) attached to the pin contact  20 . The pin housing  21  includes: the pair of pin-side lock portions  54  (first retaining portion) that prevents the upper socket connector  10  mated with the pin connector  6  from being disengaged from the pin connector  6 ; and the pair of pin-side lock portions  54  (second retaining portion) that prevents the lower socket connector  11  mated with the pin connector  6  from being disengaged from the pin connector  6 . The pin contact  20  includes: the upper contact portion  31  (first contact portion) that has a flat plate shape and is capable of being in electrical contact with the upper socket connector  10 ; the lower contact portion  32  that has a flat plate shape and is capable of being in electrical contact with the lower socket connector  11 ; and the electrode contact portion  30  (third contact portion) that has a flat plate shape and is capable of being in electrical contact with the battery  2 . The thickness direction of the upper contact portion  31  and the thickness direction of the lower contact portion  32  are substantially perpendicular to the thickness direction of the electrode contact portion  30 . The direction in which the upper socket connector  10  is mated with the pin connector  6  is different from the direction in which the lower socket connector  11  is mated with the pin connector  6 . The above structure contributes to downsizing of the pin connector  6  in the battery width direction when viewed along the thickness direction of the electrode contact portion  30 , as compared with the case where the thickness direction of the upper contact portion  31  and the thickness direction of the lower contact portion  32  are parallel or oblique to the thickness direction of the electrode contact portion  30 . 
     (2) As shown in  FIG. 1 , the direction in which the upper socket connector  10  is mated with the pin connector  6  is opposite to the direction in which the lower socket connector  11  is mated with the pin connector  6 . According to the above structure, when a plurality of batteries  2  are arranged along the direction in which the upper socket connectors  10  are respectively mated with the pin connectors  6  as shown in  FIG. 3 , each pin connector  6  is suitable for use in connecting a pair of adjacent batteries  2 . 
     (3) As shown in  FIG. 1 , the direction in which the upper socket connector  10  is mated with the pin connector  6  and the direction in which the lower socket connector  11  is mated with the pin connector  6  are substantially parallel to the thickness direction of the electrode contact portion  30 . According to the above structure, when a plurality of batteries  2  are arranged along the thickness direction of the electrode contact portion  30 , each pin connector  6  is suitable for use in connecting a pair of adjacent batteries  2 . 
     (4) As shown in  FIGS. 11 and 12 , the central axis C 1  of the upper contact portion  31  does not coincide with the virtual extension Q of the central axis C 2  of the lower contact portion  32 . The central axis C 1  is parallel to the direction in which the upper socket connector  10  is mated with the pin connector  6 . The central axis C 2  is parallel to the direction in which the lower socket connector  11  is mated with the pin connector  6 . According to the above structure, when a plurality of batteries  2  are arranged along the direction in which the upper socket connector  10  is mated with the pin connector  6 , the central axis C 1  of the upper contact portion  31  of the pin connector  6  attached to one of a pair of adjacent batteries  2  does not coincide with the virtual extension Q of the central axis C 2  of the lower contact portion  32  of the pin connector  6  attached to the other one of the pair of adjacent batteries  2 . Accordingly, when a pair of adjacent batteries  2  is connected with the cable  3 , the cable  3  is inevitably warped. This results in the time and labor needed for strictly managing the length of each cable  3  being saved, unlike in the case where the central axis C 1  of the upper contact portion  31  coincides with the central axis C 2  of the lower contact portion  32 . 
     (5) As shown in  FIGS. 13 and 15 , the pin housing  21  includes a cover portion  70  (first cover portion) of the upper housing divided body  23  that covers the upper contact portion  31 , and a cover portion  70  (second cover portion) of the lower housing divided body  24  that covers the lower contact portion  32 . According to the above structure, the upper contact portion  31  is covered with the cover portion  70  of the upper housing divided body  23  and the lower contact portion  32  is covered with the cover portion  70  of the lower housing divided body  24 . Consequently, the above structure prevents direct touching of the upper contact portion  31  and the lower contact portion  32  by fingers, and contributes to prevention of electric shock. 
     The cover portion  70  includes the inner cover portion  41  and the outer cover portion  42 . 
     (6) The cover portion  70  of the upper housing divided body  23  (first housing divided body) includes: the inner cover portion  41  (first inner cover portion) formed of the distal end face covering portion  47  and the side end face covering portions  48  (a plurality of beams) respectively extending along the distal end face  31 A and both of the side end faces  31 B of the upper contact portion  31 ; and the outer cover portion  42  (first outer cover portion) that is disposed outside the inner cover portion  41  and forms the connector insertion space  51  (space) into which the upper socket connector  10  is inserted. The cover portion  70  of the lower housing divided body  24  (second housing divided body) includes: the inner cover portion  41  (second inner cover portion) formed of the distal end face covering portion  47  and the side end face covering portions  48  (a plurality of beams) respectively extending along the distal end face  32 A and both of the side end faces  32 B of the lower contact portion  32 ; and the outer cover portion  42  (second outer cover portion) that is disposed outside the inner cover portion  41  and forms the connector insertion space  51  (space) into which the lower socket connector  11  is inserted. The above structure more effectively prevents the upper contact portion  31  and the lower contact portion  32  from being directly touched by fingers, and greatly contributes to prevention of electric shock. 
     (7) The pin housing  21  is formed of at least two components including the upper housing divided body  23  and the lower housing divided body  24 . That is, the pin housing  21  includes the upper housing divided body  23  and the lower housing divided body  24 . The upper housing divided body  23  includes the cover portion  70  that covers the upper contact portion  31 . The lower housing divided body  24  includes the cover portion  70  that covers the lower contact portion  32 . According to the above structure, even when the pin housing  21  is formed of at least two components, the cover portion  70  that covers the upper contact portion  31  is not divided and the cover portion  70  that covers the lower contact portion  32  is not divided. Accordingly, even when the pin housing  21  is formed of at least two components, the strength of the cover portion  70  that covers the upper contact portion  31  and the strength of the cover portion  70  that covers the lower contact portion  32  can be easily secured. 
     (8) As shown in  FIGS. 11 and 13 , the upper housing divided body  23  includes the connecting portion covering portion  44  (first connecting portion covering portion) that covers the lower connecting portion  35  (second connecting portion) serving as a connecting portion between the lower contact portion  32  and the electrode contact portion  30 . Similarly, the lower housing divided body  24  includes a connecting portion covering portion  44  (second connecting portion covering portion) that covers the upper connecting portion  34  (first connecting portion) serving as a connecting portion between the upper contact portion  31  and the electrode contact portion  30 . According to the above structure, the upper connecting portion  34  and the lower connecting portion  35  can be covered without increasing the number of components. 
     (9) As shown in  FIG. 13 , in the upper housing divided body  23 , the pair of pin-side lock portions  54  is formed on the small side walls  53  (side walls) of the outer cover portion  42  of the cover portion  70 . The small side walls  53  are respectively opposed to the side end faces  31 B of the upper contact portion  31 . Similarly, in the lower housing divided body  24 , the pair of pin-side lock portions  54  is formed on the small side walls  53  (side walls) of the outer cover portion  42  of the cover portion  70 . The small side walls  53  are respectively opposed to the side end faces  32 B of the lower contact portion  32 . The above structure contributes to downsizing of the pin connector  6  when viewed along the thickness direction of the electrode contact portion  30  as shown in  FIG. 16 , as compared with the case where in the upper housing divided body  23 , the pair of pin-side lock portions  54  is formed on the large side walls  52 , which are opposed to the upper contact portion  31  in the thickness direction of the upper contact portion  31 , of the outer cover portion  42  of the cover portion  70 , and in the lower housing divided body  24 , the pair of pin-side lock portions  54  is formed on the large side walls  52 , which are opposed to the lower contact portion  32  in the thickness direction of the lower contact portion  32 , of the outer cover portion  42  of the cover portion  70 . 
     (10) As shown in  FIG. 2 , a connection object unit  71  includes the battery  2  and the connector assembly  1 . 
     (11) As shown in  FIG. 3 , a connection object unit assembly  72  has a structure in which a plurality of connection object units  71  are disposed in the thickness direction of the electrode contact portion  30 . 
     As shown in  FIG. 11 , the thickness direction of the upper contact portion  31  and the thickness direction of the lower contact portion  32  are substantially parallel to each other. The above structure contributes to downsizing of the pin connector  6  in the battery width direction, as compared with the case where the upper contact portion  31  and the lower contact portion  32  are not parallel. 
     As shown in  FIGS. 11 and 12 , one of the pair of contact surfaces  31 C of the upper contact portion  31  which is farther from the electrode contact portion  30  than the other one is substantially flush with one of the pair of contact surfaces  32 C of the lower contact portion  32  which is farther from the electrode contact portion  30  than the other one. The above structure contributes to downsizing of the pin connector  6  in the battery width direction, as compared with the case where one of the pair of contact surfaces  31 C of the upper contact portion  31  which is farther from the electrode contact portion  30  than the other one is not flush with one of the pair of contact surfaces  32 C of the lower contact portion  32  which is farther from the electrode contact portion  30  than the other one. 
     As shown in  FIG. 1 , in the first exemplary embodiment, the direction in which the upper socket connector  10  is mated with the pin connector  6  is the downward direction. The direction in which the lower socket connector  11  is mated with the pin connector  6  is the upward direction. 
     As shown in  FIGS. 1 to 4 , in the state where the pin connector  6  is attached to the battery  2 , the lower housing divided body  24  of the pin housing  21  of the pin connector  6  is opposed to the corresponding side surface  4 E of the battery body  4  in the battery width direction. 
     The first exemplary embodiment described above can be modified as follows. 
     In the first exemplary embodiment described above, the pin contact  20  is formed by bending a single metallic plate M as shown in  FIGS. 11 and 12 . Alternatively, the electrode contact portion  30 , the upper contact portion  31 , and the lower contact portion  32  may be prepared as separate components, and the upper contact portion  31  and the lower contact portion  32  may be welded to the electrode contact portion  30 . 
     Second Exemplary Embodiment 
     Next, a second exemplary embodiment will be described with reference to  FIG. 19 .  FIG. 19  shows a perspective view of the pin contact  20 . Differences between the second exemplary embodiment and the first exemplary embodiment will be mainly described, while a repeat of previous descriptions is omitted. 
     As shown in  FIG. 19 , in the second exemplary embodiment, the pin contact  20  includes the electrode contact portion  30  (third contact portion), a back contact portion  80  (first contact portion), and a front contact portion  81  (second contact portion). 
     The thickness direction of the back contact portion  80  and the thickness direction of the front contact portion  81  are substantially perpendicular to the thickness direction of the electrode contact portion  30 . This contributes to downsizing of the pin connector  6  in the battery width direction. 
     The back contact portion  80  projects in the battery backward direction from the electrode contact portion  30 . The front contact portion  81  projects in the battery forward direction from the electrode contact portion  30 . Accordingly, the direction in which a connector connected to the back contact portion  80  is mated with the pin connector  6  is opposite to the direction in which a connector connected to the front contact portion  81  is mated with the pin connector  6 . Specifically, the direction in which the connector connected to the back contact portion  80  is mated with the pin connector  6  is the battery forward direction, and the direction in which the connector connected to the front contact portion  81  is mated with the pin connector  6  is the battery backward direction. 
     A central axis C 80  of the back contact portion  80  does not coincide with the virtual extension Q of a central axis C 81  of the front contact portion  81 . In other words, the back contact portion  80  and the front contact portion  81  are disposed at different locations in the battery vertical direction. The back contact portion  80  is formed so as to be bent upward from the electrode contact portion  30 . The front contact portion  81  is formed so as to be bent downward from the electrode contact portion  30 . This results in the time and labor needed for strictly managing the length of each cable  3  being saved. 
     Third Exemplary Embodiment 
     Next, a third exemplary embodiment will be described with reference to  FIG. 20 .  FIG. 20  shows a perspective view of the pin contact  20 . Differences between the third exemplary embodiment and the first exemplary embodiment will be mainly described, while a repeat of previous descriptions is omitted. 
     As shown in  FIG. 20 , in the third exemplary embodiment, the pin contact  20  includes the electrode contact portion  30  (third contact portion), a back contact portion  82  (first contact portion), and a front contact portion  83  (second contact portion). 
     The thickness direction of the back contact portion  82  and the thickness direction of the front contact portion  83  are substantially perpendicular to the thickness direction of the electrode contact portion  30 . This contributes to downsizing of the pin connector  6  in the battery width direction. 
     The back contact portion  82  projects in the battery backward direction from the electrode contact portion  30 . The front contact portion  83  projects in the battery forward direction from the electrode contact portion  30 . Accordingly, the direction in which a connector connected to the back contact portion  82  is mated with the pin connector  6  is opposite to the direction in which a connector connected to the front contact portion  83  is mated with the pin connector  6 . Specifically, the direction in which the connector connected to the back contact portion  82  is mated with the pin connector  6  is the battery forward direction, and the direction in which the connector connected to the front contact portion  83  is mated with the pin connector  6  is the battery backward direction. 
     Fourth Exemplary Embodiment 
     Next, a fourth exemplary embodiment will be described with reference to  FIG. 21 .  FIG. 21  shows a perspective view of the pin contact  20 . Differences between the fourth exemplary embodiment and the first exemplary embodiment will be mainly described, while a repeat of previous descriptions is omitted. 
     As shown in  FIG. 21 , in the fourth exemplary embodiment, the pin contact  20  includes the electrode contact portion  30  (third contact portion), an upper contact portion  84  (first contact portion), and a front contact portion  85  (second contact portion). 
     The thickness direction of the upper contact portion  84  and the thickness direction of the front contact portion  85  are substantially perpendicular to the thickness direction of the electrode contact portion  30 . This contributes to downsizing of the pin connector  6  in the battery width direction. 
     The upper contact portion  84  projects upward from the electrode contact portion  30 . The front contact portion  85  projects in the battery forward direction from the electrode contact portion  30 . Accordingly, the direction in which a connector connected to the upper contact portion  84  is mated with the pin connector  6  is different from the direction in which a connector connected to the front contact portion  85  is mated with the pin connector  6 . Specifically, the direction in which the connector connected to the upper contact portion  84  is mated with the pin connector  6  is the downward direction, and the direction in which the connector connected to the front contact portion  85  is mated with the pin connector  6  is the battery backward direction. 
     Accordingly, in the case of arranging a plurality of batteries  2  in the battery vertical direction as shown in  FIG. 3 , work for mating the lower socket connector  11  with the pin connector  6  is facilitated by attaching the pin connector  6  of the fourth exemplary embodiment to the lowermost battery  2 . 
     From the invention thus described, it will be obvious that the embodiments of the invention may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended for inclusion within the scope of the following claims.