Patent Publication Number: US-8529275-B2

Title: Assembled component having electrical connector and electrical connector cap, electrical connector cap, and method of mounting electrical connector

Description:
BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT 
     The present invention relates to an assembled component having a plurality of electrical connectors arranged on a circuit board in a specific positional relationship with each other and an electrical connector cap that is attached to the electrical connectors before disposing on the circuit board so as to join the connectors in the specific positional relationship. The present invention also relates to an electrical connector cap and a method of mounting the electrical connector. 
     When a plurality of electrical connectors (also referred to as connectors) is disposed on a circuit board in a specific positional relationship with each other, the connectors may be attached to an electrical connector cap to join the connectors before disposing the connectors on the circuit board. Then, the connectors are disposed on the circuit board while the connectors are maintained in the specific positional relationship with each other. In this case, in order to securely dispose the connectors in the specific positional relationship with each other, it is necessary to securely maintain the connectors attached to the cap so as not to be displaced from regular positions thereof. 
     As a conventional method of joining a plurality of connectors with the electrical connector cap, two joining members as the electrical connector cap may be attached to the connectors at one ends and the other ends thereof in a longitudinal direction thereof. The joining members extend in a lateral direction and have an elongated shape. Each of the connectors has a rectangular shape, and terminals are arranged in each of the connectors in a terminal arrangement direction corresponding to the longitudinal direction of the connectors, and the lateral direction corresponds to a direction perpendicular to the longitudinal direction. Accordingly, the connectors can be disposed on the circuit board with an interval in between in the lateral direction so as to be parallel to each other. 
     In the conventional method, however, the two joining members are attached to two connectors at the ends thereof so as to form a link mechanism. Accordingly, the two joining members may easily move and displace relative to each other in the longitudinal direction while the two connectors are arranged in parallel to each other. When the joining members move and displace, the two connectors may also displace, thereby making it difficult to dispose the connectors on the circuit board with the specific interval in between. 
     Patent Reference has disclosed a conventional electrical connector cap as a separate member. According to Patent Reference, the conventional electrical connector cap is attached to two connectors having an outer shape of a rectangular prism from above. Accordingly, the two connectors are joined with the conventional electrical connector cap respectively prior before the two connectors are disposed on the circuit board. 
     Patent Reference: Japanese Patent Publication No. 09-153384 
     According to Patent Reference, the conventional electrical connector cap has two cap sections. Each of the cap sections extends in a longitudinal direction thereof and covers an upper portion of the connectors. Further, a plurality of ribs extending in the lateral direction is provided for connecting the cap sections. Therefore, whereas the conventional electrical connector cap is formed as the separate member, the conventional electrical connector cap is formed in a generally flat board, extending in the longitudinal direction and the lateral direction perpendicular to the longitudinal direction. Accordingly, a relative positional relationship of the two caps is secured with the ribs so as not to change. 
     According to Patent Reference, the rib located at the two ends of the connectors in the longitudinal direction has an aligning plate. The aligning plate extends downward from the rib at a center position in the lateral direction of the connector, i.e., at a position between the two connectors. The aligning plate has a plate surface vertical to the longitudinal direction. The aligning plate further has end surfaces at both ends thereof in the width direction, i.e., the lateral direction, and the end surfaces abut sidewalls of the two connectors, so that the connectors are arranged with a specified distance from each other. 
     In addition to the aligning plate, the two cap sections has a plurality of elastic engaging pieces that extend downward from the sidewalls, which are away from each other in the lateral direction. Each of the elastic engaging pieces abuts against the sidewall of the connector in the lateral direction to press the sidewall in the direction when the conventional electrical connector cap is attached to the connector. 
     Therefore, the elastic engaging pieces restrict the connectors from moving away from the aligning plates, so that the sidewall surfaces of the connectors, which face each other, tightly abut against the side end surface of the positioning plate. In addition, the cap section has a groove section, which is opened downward and extends in the longitudinal direction (the terminal arrangement direction), so as to accommodate an upper-side portion of a housing of the connector and contact sections of the terminals protruding from a side surface of the upper-side portion. 
     According to Patent Reference, the conventional electrical connector cap is provided with the aligning plate and the elastic engaging pieces, so that the connectors are positioned in the lateral direction. The elastic engaging pieces, however, are formed to be elastically displaceable in the lateral direction. Accordingly, when the elastic engaging pieces move elastically, it is difficult to apply a sufficient restricting force to the connectors, so that the connectors may come off from the regular position in the lateral direction. 
     In addition, according to Patent Reference, the cap sections include the grooves for accommodating the upper portion of the connector and the contact sections of the terminals. However, Patent Reference does not mention whether the inner wall surfaces of the groove section restrict the connectors from moving in the lateral direction. The inner surfaces of the grooves abut against the contact sections of the terminals protruding from the side surfaces of the upper portion. Accordingly, even if the inner wall surfaces of the groove section restrict the connectors, the connector may displace in the lateral direction when the contact sections of the terminals elastically displace similar to the elastic engaging pieces. 
     Moreover, Patent Reference does not mention how the connectors are positioned in the longitudinal direction, and there is a possibility that the movement of the connectors in the direction may not be restricted. 
     Therefore, according to Patent Reference, the conventional electrical connector cap may not be capable of effectively restricting the connectors from moving in each direction. Accordingly, the connectors may be inaccurately positioned, so that the connectors are arranged away from the correct regular positions before the connectors are disposed onto the circuit board. As a result, the connectors disposed on the circuit board may become off-positioned from the regular positions, and it is difficult to dispose the connectors in the specific positional relationship to each other. 
     In view of the problems described above, an object of the present invention is to provide an assembled component having an electrical connector and an electrical connector cap. In the present invention, it is possible to effectively prevent the electrical connector from shifting away from a regular position before the electrical connector is disposed onto a circuit board. A further object of the present invention is to provide an electrical connector cap and a method of mounting the electrical connector. 
     Further objects and advantages of the invention will be apparent from the following description of the invention. 
     SUMMARY OF THE INVENTION 
     In order to attain the objects described above, according to a first aspect of the present invention, an assembled component of electrical connectors and an electrical connector cap includes the plurality of electrical connectors to be disposed on a circuit board with a specific positional relationship to each other; and the electrical connector cap to join the plurality of electrical connector with the specific positional relationship to each other, and the electrical connector cap is to be attached to the plurality of connectors before disposing the connectors onto the circuit board. 
     In the assembled component of the electrical connectors and the electrical connector cap, the electrical connector cap includes a main body, which extends in two directions that are vertical to each other within one surface parallel to the circuit board upon disposing the plurality of connectors onto the circuit board, and a plurality of cap-side fitting section pairs, which fits to the respective electrical connectors at two positions in a direction vertical to the circuit board. 
     Each of the electrical connectors has a connector-side fitting pair, to which the cap-side fitting section pair fits. The plurality of cap-side fitting section pairs and the corresponding connector-side fitting section pairs have reference surfaces formed to set positions of the respective electrical connectors in concert with each other in the two directions, so that among all the connectors, the cap-side fitting section pairs and the connector-side fitting section pairs cooperate to maintain the specific positional relationship among the plurality of electrical connectors. 
     According to the present invention, the plurality of cap-side fitting sections and the connector-side fitting section pairs have the reference surfaces formed in two directions that are vertical to each other within one surface parallel to the circuit board. Once the electrical connector cap is attached to the plurality of electrical connectors, the reference surfaces of the cap-side fitting pairs and the corresponding reference surfaces of the connector-side fitting section pairs abut against each other in the two directions. 
     Therefore, in the respective electrical connectors, the cap-side fitting sections of each of the cap-side fitting pairs and the cap-side fitting sections of each of the cap-side fitting section pairs work in concert, so as to set the positions of the respective electrical connectors in the two directions. As a result, the specific positional relationship among the plurality of electrical connectors in the two directions is maintained. In addition, since the reference surfaces of the cap-side fitting section pairs and the connector-side fitting section pairs do not elastically displace, the connectors will not displace from the specific positional relationship. 
     When the electrical connectors are used, the connector-side fitting section pairs are preferably capable of fitting to the corresponding fitting section pairs of the mating connector in a direction vertical to the circuit board. More specifically, upon the use of the electrical connectors, the connector-side fitting section pairs to fit to the corresponding fitting section pairs of the mating connector are used also as fitting section pairs to fit to the cap-side fitting section pairs upon disposing the connector onto the circuit board before using the electrical connectors. Accordingly, it is not necessary to provide another fitting pairs to fit to the cap-side fitting section pairs in addition to the connector-side fitting section pairs to fit to the corresponding fitting section pairs of the mating connector, and it is possible to avoid increase of the connector size. In addition, since the electrical connectors have a simplified shape, it is possible to reduce a manufacturing cost thereof. 
     Preferably, the cap-side fitting section pairs and the connector-side fitting section pairs have one recess formed in the electrical connector housing or the cap main body, and one protrusion that is provided on the other and to be fitted to attach to the recess in a direction perpendicular to the circuit board. Moreover, it is preferred to form the reference surfaces on an inner wall surface of the recess and an outer wall surface of the protrusion. 
     The cap main body preferably has a plate surface that extends parallel to the circuit board. By forming the main body to have the plate surface as described above, the plate surface can be used as a suctioning surface to suction and transport the electrical connector to an implementation position using a suctioning member upon implementation of the electrical connector. Accordingly, it is easier to transport the assembled component of the connectors and the electrical connector cap. 
     According to the present invention, the electrical connector cap is attached to the plurality of electrical connectors, which is to be disposed on the circuit board with the specific positional relationship and joins the plurality of electrical connectors with the specific positional relationships, before the electrical connectors are arranged on the circuit board. 
     According to the present invention, the electrical connector cap includes the main body that extends in the two directions that are perpendicular to each other within one surface parallel to the circuit board upon disposing the plurality of electrical connectors to the circuit board; and the plurality of cap-side fitting section pairs to fit to the respective electrical connectors at two positions in the direction vertical to the circuit board. 
     The electrical connectors have the connector-side fitting section pairs to which the cap-side fitting section pairs fit, and the plurality of cap-side fitting section pairs and the corresponding connector-side fitting section pairs have the reference surfaces that cooperate to position the respective electrical connectors in the two directions. With the configuration of the electrical connector cap, the cap-side fitting section pairs and the connector-side fitting section pairs work in concert, and all the electrical connectors can be maintained in the specific positional relationships from each other. 
     According to the invention, a method of mounting the electrical connector includes the steps of mounting the plurality of electrical connectors on the circuit board with the specific positional relationships. According to the method, after attaching the electrical connector cap for joining the plurality of electrical connectors with the specific positional relationship to the plurality of electrical connectors, the plurality of electrical connectors are disposed and implemented thereon. 
     In the method of mounting the electrical connectors, according to the invention, the cap has the main body, which extends in two directions that are vertical to each other within the surface that is parallel to the circuit board upon disposing the plurality of electrical connectors onto the circuit board; and the plurality of cap-side fitting section pairs to fit the cap-side fitting section pairs. 
     Each of the electrical connectors has the connector-side fitting section pairs to fit to the cap-side fitting pair and the plurality of cap-side fitting pairs and the corresponding connector-side fitting section pairs cooperate to each other so as to form the reference surfaces to position the electrical connectors in the two directions. When the cap-side fitting section pairs are fitted to the corresponding connector fitting section pairs, the plurality of electrical connectors is disposed and implemented on the circuit board while maintaining the specific positional relationship among the plurality of electrical connectors by cooperation of the cap-side fitting section pairs and the connector-side fitting section pairs. 
     As described above, according to the present invention, the reference surfaces are formed on the cap-side fitting section pairs and the connector-side fitting section pairs in the two directions that are vertical to each other. Accordingly, each of the electrical connectors is positioned in the two directions by cooperation of the cap-side fitting sections of each pair and cooperation of the connector-side fitting sections of each pair. Therefore, it is possible to maintain the specific positional relationships in the two directions among the plurality of electrical connectors. 
     In addition, since the reference surfaces of the cap-side fitting section pairs and the connector-side fitting section pairs would not be elastically displaced, the electrical connectors will not be displaced and thereby it is possible to maintain the specific positional relationship thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing an electrical connector in a state before the electrical connector is fitted to an intermediate connector and a mating connector according to a first embodiment of the present invention; 
         FIG. 2  is a perspective view showing an electrical connector cap and the electrical connectors in a state that the electrical connector cap is separated from the electrical connectors according to the first embodiment of the present invention; 
         FIG. 3  is a perspective view showing the electrical connector cap and the electrical connectors in a state that the electrical connector cap is attached to the electrical connectors according to the first embodiment of the present invention; 
         FIGS. 4(A) and 4(B)  are sectional views showing the electrical connectors and the electrical connector cap according to the first embodiment of the present invention, wherein  FIG. 4(A)  is a sectional view taken along a line IVA-IVA in  FIG. 3  and  FIG. 4(B)  is a sectional view taken along a line IVB-IVB in  FIG. 3 ; 
         FIG. 5  is a perspective view showing an electrical connector cap and electrical connectors in a state that the electrical connector cap is separated from the electrical connectors according to a second embodiment of the present invention; 
         FIG. 6  is a perspective view showing the electrical connector cap and the electrical connectors in a state that the electrical connector cap is attached to the electrical connectors according to the second embodiment of the present invention; and 
         FIG. 7  is a sectional view of the electrical connectors and the electrical connector cap taken along a line VII-VII in  FIG. 6  according to the second embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Hereunder, referring to the accompanying drawings, embodiments of the invention will be described. 
     &lt;First Embodiment&gt; 
       FIG. 1  is a total perspective view of a connector, which is to be connected to a mating connector via an intermediate connector, the intermediate connector, and the mating connector in a state before fitting to each other, according to this invention. In the embodiment, two circuit board electrical connectors  1  and  2  (hereunder, referred to as “connector  1 ” and “connector  2 ”) have an identical shape to each other and are connectors to be respectively disposed onto corresponding circuit boards (not illustrated). The connector  1  and the connector  2  connect to each other via the intermediate connector  3 . 
     More specifically, as shown in  FIG. 1 , the connector  1  is provided under the intermediate connector  3 , and is connected to a lower end-side portion of the intermediate connector  3 . On the other hand, the mating connector  2  is disposed above the intermediate connector  3 , while being inversed in the up-and-down direction in relative to the connector  1 , and fitted and connected to an upper end-side portion of the intermediate connector  3 . Fitting and connecting the connector  1  and the mating connector  2 , which are respectively disposed on the corresponding circuit boards, to the intermediate connector  3 , those circuit boards are electrically connected to each other with their board surfaces extending parallel to each other. 
     As will be described later, according to the embodiment, a plurality of the connector  1  and the same number of the mating connectors  2  are disposed on respective circuit boards with specific positional relationships, and thereby the connectors  1  and their mating connectors  2  connect to each other via the intermediate connectors  3 . Here, “the specific positional relationships” are set in advance according to requirements upon designing. 
     Before disposing the plurality of connectors  1  on a circuit board, a cap  4  is attached thereto and thereby the connectors are joined by the cap while keeping the specified intervals from each other (See  FIGS. 2 and 3 ). Then, the plurality of connectors  1  are conveyed with the caps  4  being attached thereto, and then disposed onto circuit boards while keeping the specified spacing from each other. 
     As shown in  FIG. 1 , the connector  1  has a housing  10  that has an outer shape of a generally rectangular prism and is made of synthetic resin; a plurality of metal terminals  20  that are to be arranged and held in the housing  10  along the longitudinal direction thereof, and metal fittings  30  to be held by the housing  10  at end sections of the housing  10  in the longitudinal direction. 
     The housing  10  has receiving space  11 , which is opened upward to receive the intermediate connector  3 . A circumferential wall that surrounds the receiving space  11  is formed by a pair of sidewalls  12  extending in the longitudinal direction of the housing  10 , and a pair of end walls  13  that joins the both end sections of the pair of sidewalls  12  in the longitudinal direction. 
     Moreover, at a center part of the receiving space  11 , there is provided an island-like center wall section  14  extending in the longitudinal direction of the housing  10 , i.e., in the terminal arrangement direction. The receiving space  11  is annularly formed between the center wall section  14  and the circumferential wall of the housing  10  so as to surround the center wall section  14 . On each sidewall surface of the center wall section  14 , there are formed terminal housing grooves  14 A at positions corresponding to the terminals  20  in the longitudinal direction so as to extend in the up-and-down direction (connector height direction). 
     As shown in  FIG. 1 , on the both end walls  13  of the housing  10 , there are provided fitting recesses  15  as cap-side fitting sections being opened upward so as to form a part of the receiving space  11 . Prior to disposing each connector  1  onto a circuit board, each fitting recess  15  receives a fitting protrusion  82  of the cap  4  to fit to the fitting protrusion  82 . In addition, upon connector fitting, as will be described below, each fitting recess  15  serves as a guiding section to guide therein the flat wall section  44  of the end wall  43  of the intermediate connector  3  as will be described below, and thereby receives the flat wall section  44  and a hook section  45 , which will be described below. 
     As described above, each fitting recess  15  is a part of the receiving space  11 , and is formed by a U-shaped groove-like inner wall surface of the end wall  13  at each both end positions in the longitudinal direction of the housing  10  and a flat end surface wall of the center wall section  14 . The inner wall surface of each end wall  13  is composed of two surfaces that face each other in the lateral direction of the housing  10  and a surface that faces the end wall surface of the center wall surface  14  in the longitudinal direction, and has a U-groove-like shape when viewed from thereabove. 
     Each end wall surface of the center wall section  14  extends vertically to the longitudinal direction and serves as a reference surface  15 A to position the connector  1  in the longitudinal direction upon attaching the cap  4  to the connector  1  as will be described below (see  FIGS. 2 ,  4 (A), and  4 (B). 
     In addition, among the inner wall surfaces of the end walls  13 , two surfaces facing each other in the lateral direction extends vertically to the lateral direction and as will be described, upon attaching the cap  4  onto the connector  1 , it serves as reference surfaces  15 B and  15 C to position the connector  1  in the lateral direction (See  FIG. 4(B) ). 
     As shown in  FIG. 1 , each terminal  20  has a generally L shape formed by bending a lower end side of a metal strip piece generally vertically to the sheet thickness direction. Being bent, the lower end section of the terminal  20  that extends in the lateral direction of the housing  10  extends sideward outside the housing  10  as a connecting section  21  to connect to a corresponding circuit section formed on the circuit board. Moreover, an upper section of each terminal  20  that extends upward is bent sideward so as to be convexly curved, and its convexly curved part protrudes into the receiving space  11  and is provided as a contact section  22  to contact with an intermediate terminal  61  of the intermediate connector  3 , which will be described later. 
     Each terminal  20  is pressed from the contact section  22  side via a terminal insertion hole (not illustrated) formed on a bottom surface of the housing  10 , and held in the terminal holding groove  14 A of the central wall section  14 . As shown in  FIG. 1 , each contact section  22  is provided to protrude in the receiving space  11 , and as already described above, each connecting section  21  extends outward of the connector  1  in the lateral direction. 
     As shown in  FIG. 1 , the metal fittings  30  are provided on the both end walls  13  of the housing  10 . Each metal fitting  30  is made of sheet metal, and has a flat sheet section  31  to be held by the housing  10 , and a pair of legs  32  that extends from a lower end of the flat sheet section  31  in a direction to be away from each other in the lateral direction of the housing  10 . Each metal fitting  30  is attached to the housing  10 , by pressing side edge sections of the flat sheet section  31  in attachment section (not illustrated), which is formed on the both end walls  13  of the housing  10  and extends in the connector height direction (up-and-down direction), from therebelow. 
     One metal fitting  30  is provided for each end wall  13 , and the pair of legs  32  extends from the lower end of the attachment hole and lower edges of the pair of legs  32  are connected by soldering to the circuit board and thereby the connector  1  is secured on the circuit board. 
     Furthermore, each flat sheet section  31  is held such that its plate surface faces the end wall surface (reference surface  15 A) of the center wall section  14  of the housing  10  in the longitudinal direction. Each flat sheet section  31  has a hole formed therein, and the upper edge section that forms the hole serves as a latching section  31 A to latch to the cap  4  or the intermediate connector  3 . 
     More specifically, upon attaching the cap  4  onto the connector  1 , the latching section  31 A latches onto a latching protrusion  81 A of the cap  4  in the attachment direction (up-and-down direction) of the cap  4  (See  FIGS. 3 and 4(A) ). In addition, upon fitting the connector  1  to the intermediate connector  3 , the latching section  31 A latches to a latching claw  45 A of the intermediate connector  3  in the connector fitting section (up-and-down direction). 
     Since the mating connector  2  has the same configuration as that of the connector  1 , the explanation will be omitted. 
     As shown in  FIG. 1 , the intermediate connector  3  has a housing  40 , which is made by joining synthetic resin tubular bodies  40 A,  40 B, and  40 A in the up-and-down direction, and two flat sheet-like blade assemblies  50  that are to be held in the housing  40  facing to each other in the lateral direction of the housing  40 . The housing  40  has an outer shape of a rectangular prism, and has a holding space  41  penetrating therethrough in the up-and-down direction to hold the blade assemblies  50 . A circumferential wall that forms the holding space  41  is made by a pair of sidewalls  42  that extend in the longitudinal direction of the housing  40  and a pair of end walls  43  that join the ends of the pair of sidewalls  42  in the longitudinal direction. 
     Each end wall  43  of the housing  40  has its lower part dented in the longitudinal direction, in relative to an end surface of the intermediate portion in the up-and-down direction. Each end wall  43  has at the lower portion a flat wall section  44 , a flat surface of which is vertical to the longitudinal direction; and a hook section  45  that extends parallel to the flat wall section  44  in the longitudinal direction at a position that is outer from the connector than the flat wall section  44  and away from the flat wall section  44  in the longitudinal direction and forms a cantilever-like flat section. 
     Each flat wall section  44  has a guiding surface  44 A formed as a tapered surface on an outer surface at the lower end. Upon fitting the intermediate connector  3  to the connector  1 , the guiding surface  44 A abuts to an upper edge section of the fitting recess  15  of the connector  1 , and thereby the flat wall section  44  is smoothly guided into the fitting recess. 
     The hook section  45  can elastically flexed and displaced towards the flat wall section  44  in the sheet thickness direction (in the aforementioned longitudinal direction), and has at its tip a latching claw  45 A protruding outward of the connector  3  in the longitudinal direction. While the connector  1  and the intermediate connector  3  are being fitted to each other, the latching claw  45 A of each hook section  45  latches to the latching section  31 A of the metal fitting  30  of the connector  1  in the connector fitting direction, i.e. connector height direction (the up-and-down direction in  FIG. 1 ), so that coming off of the connectors therefrom is prevented. 
     Except for not having a part corresponding to the hook section  45 , since a shape of an upper part of the housing  40  is the same as that of a lower part of the housing  40 , which has been described above, the explanation will be omitted. 
     As shown in  FIG. 1 , the two blade assemblies  50  are held within the holding space  41  of the housing  40  such that the plate surfaces face each other in the lateral direction of the intermediate connector  3 . Each blade assembled component  50  has blades  60  that are formed by arranging on a flat circuit board surface a plurality of intermediate terminals  61  that extend parallel to each other, and has one grounding plate  70  that is attached thereto as a flat metal member and shared by the plurality of blades  60 . As shown in  FIG. 1 , in each blade assembled component  50 , the plurality of blades  60  is arranged having side edges adjacent to each other in the longitudinal direction of the intermediate connector  3  so as to be positioned on the same flat surface that extends vertically to the lateral direction, while the intermediate terminals  61  extends in the connector height direction. In other words, the plurality of intermediate terminals  61  is arranged in the longitudinal direction. 
     As shown in  FIG. 1 , while the housing  40  holds the blade assemblies  50 , the lower part of each blade assembled component  50  protrudes lower than the lower edge of the housing  40 . In a state that the connector  1  and the intermediate connector  3  are fitted to each other, the protruding lower part of each blade assembled component  50  enters the receiving space  11  of the connector  1 , and each intermediate terminal  61  contacts with a contact section  22  of the terminal  20  of the connector  1 . In addition, there is formed space between lower parts of the two blade assemblies  50  and the center wall section  14  of the connector  1  is configured to enter the space in the connector fitting state. 
     Since the form of the upper part of the intermediate connector  3  is symmetrical to the aforementioned lower part of the intermediate connector  3  in the up-and-down direction, the explanation will be omitted. 
     Next, a configuration of the cap  4  will be described.  FIG. 2  is a total perspective view of the connector  1  and the cap  4 , which are separated from each other, according to this embodiment. In the figure, two connectors  1  are shown with the cap  4 . As shown in the figure, the two connectors  1  will be disposed to be parallel to each other at specific interval therebetween in the lateral direction of the connector  1  on a circuit board (not illustrated) using the cap  4 . 
     As shown in  FIG. 2 , the cap  4  is made of synthetic resin, and has a quadrangle sheet-like main body  81 , and a plurality of fitting protrusions  82 , which extend downward from four corners of the main body  81  and serve as cap-side fitting sections. The main body  81  has a rectangular flat surface, and  FIG. 2  is provided such that the longitudinal direction and the lateral direction of the main body  81  respectively correspond to those of the connectors  1 . The main body  81  is made to have almost the same size as the connector  1  in the longitudinal direction, and is configured to cover most part of upper surfaces of the both connectors  1  in state of being attached to the two connectors  1  (see  FIG. 3 ). 
     The fitting protrusions  82  are provided at positions corresponding to those of the pair of fitting recesses  15  provided at the both ends of each connector  1  in the longitudinal direction, and the two fitting protrusions  82  that correspond to each pair of the fitting recesses  15  are paired. More specifically, the cap  4  has two pairs of fitting protrusions  82 . Each fitting protrusion  82  has a flat leg  83  that is provided on an inner side of the cap  4  in the longitudinal direction of the cap  4  than an edge sections that extend in the lateral direction of the cap  4  and has a surface vertical to the longitudinal direction; and a flat cantilever-like elastic piece  84  extending downward from the edge section and having a flat surface parallel to a plate surface of the flat leg  83 . 
     The flat legs  83  of the fitting protrusions  82  of each pair have their plate surfaces facing each other in the longitudinal direction of the cap  4  abut to the reference surfaces  15 A of the fitting recesses  15  of the connector  1  and serve as reference surfaces  83 A that position each connector  1  in the longitudinal direction (see also  FIGS. 4(A) and 4(B) ). In addition, two thick flat surfaces of each flat leg  83 , which are vertical to the lateral direction of the connector  1 , abut to the reference surfaces  15 B and  15 C of the connector  1  and serve as reference surfaces  83 B and  83 C to position each connector  1  in the lateral direction (see also  FIG. 4(B) ). 
     In each pair of fitting protrusions  82 , the distance between the reference surfaces  83 A of the pair of flat legs  83  in the longitudinal direction is almost equal to the distance between the pair of reference surfaces  15 A of the connector  1  in the longitudinal direction, i.e. the dimension of the center wall section  14  in the longitudinal direction (see  FIG. 4(B) ). In addition, in each fitting protrusion  82 , the distance between the reference surface  83 B and the reference surface  83 C in the lateral direction, i.e. the dimension of the flat leg  83  in the lateral direction is almost equal to the distance between the reference surface  15 B and the reference surface  15 C in the longitudinal direction of the connector  1  (see  FIG. 4(B) ). 
     Furthermore, as for the two pairs of fitting protrusions  82  of the cap  4 , the distance between the reference surface  83 B/ 83 C of one pair of fitting protrusions  82  and the reference surfaces  83 B/ 83 C of the other pair of fitting protrusions  82  in the lateral direction is the same as the pre-set specified spacing between the connectors  1 . 
     Each elastic piece  84  can be elastically flexed and displaced towards the flat leg  83  in its sheet thickness direction (the aforementioned longitudinal direction), and at a lower part of the plate surface provided a way from the flat leg  83 , which is one of the two plate surfaces that are vertical to the longitudinal direction, there is formed a latching protrusion  84 A that latches to the latching section  31 A of the metal fitting  30  of the connector  1  in the up-and-down direction, in a state of the cap  4  attached to the connector  1 . 
     Hereunder, referring to  FIGS. 2 through 4 , implementation of the two connectors  1  onto a circuit board will be described.  FIG. 3  is a partial cutaway perspective view of the connector  1  and the cap  4  of  FIG. 2 , in which a part of the fitting portion of the fitting protrusion  82  and the fitting recess  15  is provided in a sectional view. In addition,  FIG. 4  is a sectional view of the connector  1  and the cap  4  of  FIG. 3 , in which (A) is a IVA-IVA sectional view and  FIG. 4(B)  is a IVB-IVB sectional view.  FIG. 4(A)  is a cross-section of the connector  1  and the cap  4 , which is taken in a direction vertical to the lateral direction of the connector  1 , and  FIG. 4(B)  is a section of the connector  1  and the cap  4 , which is taken in a direction vertical to the longitudinal direction of the connector  1 . 
     First, as shown in  FIG. 2 , prior to attaching the cap  4 , the two connectors  1  are disposed on a same flat surface with pre-set specified spacing therebetween in the lateral direction of the connector  1 . Then, bringing the cap  4  over to above the two connectors  1 , the cap  4  and the connectors  1  are aligned in the longitudinal direction and the lateral direction and each pair of fitting protrusions  82  are positioned to right above the fitting recesses  15  of the connector  1 . 
     Next, moving the cap  4  downward, the pair of fitting protrusions  82  f the cap  4  is fitted in the pair of fitting recesses  15  of the corresponding one connector  1  from thereabove, and the other pair of fitting protrusions  82  of the cap  4  is fitted within the pair of fitting recesses  15  of the other connector  1  from thereabove. By the fitting between the fitting protrusions  82  and the fitting recesses  15 , as shown in  FIG. 3 , the cap  4  is attached to the two connectors  1 , and thereby the two connectors  1  are joined in the lateral direction. In the middle of fitting between the fitting protrusions  82  and the fitting recesses  15 , the elastic piece  84  of each fitting protrusion  82  is pushed by the plate surface of the flat surface  31  of the metal fitting  30  and elastically displaces, and once it reaches the position of the hole of the flat section, it returns to its free state. 
     As a result, as shown in  FIG. 4(A) , the latching protrusion  84 A of each elastic piece  84  and the latching section  31 A of the flat section  31  are in the state of being able to latch in the inserting/removing direction (up-and-down direction) of the cap  4 . By attaching the cap  4  to the connectors  1  as described above, the assembled component of the connectors  1  and the cap  4  is completed. 
     In the middle of fitting and in a state of fitting between the fitting protrusions  82  and the fitting recesses  15 , the reference surfaces  83 A of the pair of fitting protrusions  82  and the reference surfaces  15 A of the pair of fitting recesses  15  respectively abut to each other in the longitudinal directions of the connectors  1 , and each connector  1  is positioned in the longitudinal direction. More specifically, by cooperation of the pair of reference surfaces  83 A and cooperation of the pair of the reference surfaces  15 A, each connector  1  is positioned in the longitudinal direction and is brought to its regular position in the direction. 
     In addition, the reference surfaces  83 B and  83 C of the pair of fitting protrusions  82  and the reference surfaces  15 B and  15 C of the pair of fitting recesses  15  respectively abut to each other in the lateral directions of the connectors  1 , and each connector  1  is positioned in the lateral direction. More specifically, by cooperation of the pair of reference surfaces  83 B, cooperation of the reference surfaces  83 C, cooperation of the pair of reference surfaces  15 B and cooperation of the reference surfaces  15 C, each connector  1  is positioned in the lateral direction and is brought to its regular position in the direction. 
     As described above, as a result that each connector  1  is positioned in the longitudinal direction and the lateral direction by the two types of reference surfaces that are vertical to each other, the two pairs of the fitting protrusions  82  of the cap  4  cooperate, the two pairs of the fitting recesses  15  of the two connectors  1  cooperate, and thereby it is possible to keep the specific positional relationship between the two connectors  1  in the longitudinal direction and the lateral direction. 
     The assembled component of the connectors  1  and the cap  4  is conveyed, having an upper surface of the main body  81  of the cap  4  be sucked by a suctioning device (not illustrated), and then is disposed at a specified position on a circuit board. Even upon conveying the assembled component and disposing it onto a circuit board, the two connectors  1  will not be displaced from the regular positions, so that the specific positional relationship between the two connectors  1  disposed on a circuit board is maintained. 
     Next, while keeping the cap  4  attached, the contact section  21  of each terminal  20  of each connector  1  and a corresponding circuit section (not illustrated) on a circuit board are connected by soldering to each other, and thereby implementation of the connectors  1  is completed. On the corresponding circuit section, there is a plurality of pads (not illustrate) formed at specified positions, which correspond to each connecting section  21  and is respectively connected by soldering to the connecting section  21 . According to this embodiment, as described above, since the two connectors  1  are disposed keeping the specific positional relationship, it is possible to prevent displacement of the connecting sections  21  and the pads, and to secure connection by soldering at correct positions. 
     After completion of implementation of the connectors  1 , the cap  4  is removed, and the connectors  1  are in a state of being ready to fit and connect with the intermediate connectors  3 . According to this embodiment, since the specific positional relationship between the connectors  1  is maintained, it is possible to fit and connect the two mating connectors  2 , which are disposed onto another circuit board in advance with specific positional relationship, to the respective corresponding connectors  1  via the intermediate connectors  3  at once. Furthermore, according to this embodiment, since each mating connector  2  has completely identical configuration to that of the connector  1 , it is possible to position the mating connector  2  in a similar manner using the cap  4 . 
     In this embodiment, since the main body  81  of the cap  4  is formed to have a generally flat board-like shape that extends in two directions, i.e. the longitudinal direction and the lateral direction of the main body  81 , the distance between the fitting protrusions  82  in the aforementioned two directions, on which the reference surfaces  83 A,  83 B, and  83 C for positioning the connectors  1  are formed, will not be changed. Therefore, it is possible to correctly position the connectors  1  in the above-described two directions using the reference surfaces  83 A,  83 B, and  83 C of the cap  4 . Moreover, since it is possible to use an upper surface of the main body  81  as a suctioning surface, it is possible to easily convey the assembled component of the cap  4  and the two connectors  1 . 
     According to this embodiment, the fitting recesses  15  of each connector  1  are configured to be able to fit to both the flat wall sections  44  and the hook sections  45  of the end walls  43  of the intermediate connector  3  and the fitting protrusions  82  of and the cap  4 . More specifically, upon using the connectors, the fitting recesses  15  serve as fitting sections to fit to the flat wall section  44  and the hook section  45  of the intermediate connector  3 , and upon disposing the connectors onto a circuit board before using the connectors, they serve as fitting sections to fit to the fitting protrusions  82  of the cap  4 . 
     Accordingly, since it is not necessary to separately provide fitting sections to fit to the fitting protrusions  82  of the cap  4  in addition to the fitting sections to fit to the flat wall sections  44  and the hook sections  45  of the intermediate connector  3 , it is possible to prevent increase of the size of the connector  1 . Moreover, since the shape of the connectors  1  is simplified, it is possible to reduce the manufacturing cost for that amount. 
     In addition, since the fitting recesses  15  of the connectors  1  are configured to be able to fit to the both flat wall section  44  and the hook sections  45  of the intermediate connector  3  and the fitting protrusions  82  of the cap  4 , it is possible to make the space usually provided between the fitting recesses  15  and the flat wall sections  44  and the hook sections  45  for fitting therebetween and the space usually provided between the fitting recesses  15  and the fitting protrusions  82  for fitting therebetween are almost the same. Accordingly, since it is not necessary to consider the space for the intermediate connector  3  and the space for the cap  4  separately, it is easy to manage the dimension upon manufacturing and mounting the connector  1 . 
     In this embodiment, a cap is attached to two connectors, but the number of connectors to attach the cap is not limited to this and can be 3 or more. In this case, the cap is provided with the same number of pairs of fitting protrusions as the number of connectors. 
     In this embodiment, a plurality of connectors is disposed in the lateral direction, but in this invention, the disposing direction of the connectors is not limited to this, and it is possible to dispose the connectors in any directions as long as the plurality of connectors is provided with specified spacing therebetween. For example, in a case of arranging the plurality of connectors in the longitudinal direction, it is also possible to apply the invention by forming the cap to have a shape so as to be able to attach to the plurality of connectors. 
     &lt;Second Embodiment&gt; 
     Since the cap has fitting recesses and the connector has fitting protrusions, this embodiment is different from the first embodiment, in which the cap has the fitting protrusions and the connector has the fitting recesses. 
       FIG. 5  is a total perspective view of the plurality of connectors  5  and the cap  6 , which are separated from each other.  FIG. 6  is a total perspective view showing a fitting state between the connectors  5  and the cap  6  of  FIG. 5 . In  FIG. 6 , a part of the fitting protrusion  144  of the connector  5  and a part of the fitting recess  182  of the cap  6  are shown in a sectional view. In addition,  FIG. 7  is a VII-VII sectional view of the connectors  5  and the cap  6  of  FIG. 6 , and shows a lateral sectional view taken at a fitting position of the fitting protrusions  144  and the fitting recesses  182  in the up-and-down direction. 
     As shown in  FIGS. 5 and 6 , the connector  5  of this embodiment is a connector to be implemented on a circuit board like the connector  1  of the first embodiment, and holds blade assemblies as the intermediate connector  3  of the first embodiment and fit to the mating connector (not illustrated) in the up-and-down direction. Each connector  5  has a tubular housing  140  made of synthetic resin; two flat blade assemblies  150  to be held by the housing  140  while facing to each other in the lateral direction of the housing  140 ; and securing metal fittings  130  to be held in the housing  140  at the both ends of the housing  140  in the longitudinal direction of the connector  5 . 
     Each end wall  143  of the housing  140  is dented in the longitudinal direction of the connector  5  in relative to the end surface of the other part in the up-and-down direction. An upper part of each end wall  143  has a fitting protrusion  144  that has a flat surface vertical to the longitudinal direction and serves as a connector-side fitting section. 
     Each fitting protrusion  144  is configured to have a larger thickness, i.e. a larger dimension in the longitudinal direction, in part in the lateral direction of the connector  5  in comparison with other part, and the portion having larger thickness has a tapered guiding section  145  that protrudes upward than the upper end of the blade assembled component  150 . The guiding section  145  has a pair of guiding surfaces that tilt in the longitudinal direction and a pair of guiding inner surfaces that tilt in the lateral direction. By abutting the guiding surfaces to the lower edge of the fitting recess  182  of the cap  6 , which will be described later, the fitting protrusion  144  can be smoothly guided to enter the fitting recess  182 . 
     In the fitting protrusions  144  respectively provided at both ends of the connector  5  in the longitudinal direction, the flat surfaces facing in the longitudinal direction serve as reference surfaces  144 A to position the connector  5  in the longitudinal direction upon attaching the cap  6  to the connector  5 . 
     Furthermore, as will be described later, in each fitting protrusion  144 , the two thick surfaces that are vertical to the lateral direction of the connector  5  serve as reference surfaces  144 B and  144 C to position the connector  5  in the lateral direction upon attaching the cap  6  to the connector  5  (see  FIG. 7 ). The reference surfaces  144 B and  144 C are provided at the same positions as the plate surfaces of the grounding plates  170  of the blade assemblies  150  (see also  FIG. 7 ). 
     As shown in  FIGS. 5 and 6 , except that its connecting section  162  of each terminal  161  extends at a lower part outside the housing  140  in the lateral direction and can be connected by soldering to a corresponding circuit section of a circuit board, each blade assembled component  150  has the same configuration as that of the blade assembled component  50  of the first embodiment. In addition, each securing metal fitting  130  has the same configuration as the securing metal fitting  30  of the first embodiment. 
     As shown in  FIG. 5 , the cap  6  made of synthetic resin has a quadrangle flat main body and the figure is provided aligning the longitudinal direction and the lateral direction thereof to the longitudinal directions and the lateral directions of the connectors  5 , respectively. At four corner positions of the cap  6 , there are formed a plurality of fitting recesses  182 , which serve as cap-side fitting sections, as holes penetrating in the up-and-down direction. Each fitting recess  182  is provided at a position corresponding to the pair of fitting protrusions  144  positioned at the both ends of each connector  5  in the longitudinal direction, and two fitting recesses  182  corresponding to each pair of fitting protrusions  144  are respectively paired. In other words, the cap  6  has two pairs of fitting recesses  182 . 
     Each fitting recess  182  has a quadrangle cross-section that is parallel to the plate surface of the cap  6 , and an inner wall surface of the fitting recess  182  is composed of two surfaces that face each other in the longitudinal direction and two surfaces facing each other in the lateral direction. As well shown in  FIG. 6 , within each fitting recess  182 , there is formed an elastic piece  184  that is joined to an upper part of the surface provided outer side of the cap in the longitudinal direction, which is one of the two surfaces facing in the longitudinal direction, and extends downward. The elastic piece  184  is formed like a flat cantilever that has a plate surface parallel to the surface and can be elastically flexed in the sheet thickness direction. 
     As shown in  FIG. 5 , in the inner wall surfaces of the fitting recesses  182  of each pair, surfaces facing in the longitudinal direction to surfaces provided with the elastic piece  184  abut to reference surfaces  144 A of the fitting protrusions  144  of the connector  5  and serve as reference surfaces  182 A that position each connector  5  in the longitudinal direction (see also  FIG. 7 ). In addition, in the inner wall surfaces of each pair of fitting recesses  182 , two surfaces facing in the lateral direction abut to the reference surfaces  144 B and  144 C of the connector  5  and serve as reference surfaces  182 B and  182 C that position each connector  5  in the lateral direction (see also  FIG. 7 ). 
     As seen in  FIG. 7 , in each pair of fitting recesses  182 , the distance between the pair of reference surfaces  182 A in the longitudinal direction is almost the same as the distance between the pair of reference surfaces  144 A in the longitudinal direction of the connector  5 . In addition, the distance between the reference surface  182 B and the reference surface  182 C in the lateral direction in each fitting recess  182 , i.e. a dimension of the fitting recess  182  in the lateral direction, is almost the same as the distance between the reference surface  144 B and the reference surface  144 C in the lateral direction. 
     In addition, in two pairs of fitting recesses  182  of the cap  6 , the distance in the lateral direction of the cap  6  between the reference surfaces  182 B and  182 C of one pair of fitting recesses  182  and the reference surfaces  182 B and  182 C of the other pair of fitting recesses  182  is set to the same as the pre-set specified spacing between the connectors  5 . 
     As shown in  FIG. 6 , each elastic piece  184  is configured to be elastically flexed and displaced so as to be away from the reference surface  182 A in the sheet thickness direction (the longitudinal direction), and a lower part of the plate surface provided on the side of the reference surface  182 A side, which is one of the two surfaces vertical to the longitudinal direction, has a pressing protrusion  184  formed to press the fitting protrusion  144  of the connector  5  while the cap  6  is being attached to the connector  5 . 
     Hereunder, referring to  FIGS. 5 through 7 , implementation of the two connectors  5  onto a circuit board will be described. Similarly to the first embodiment, first, as shown in  FIG. 5 , before attaching the cap  6 , the cap  6  is brought over to above the two connectors  5  disposed on one flat surface with pre-set specified spacing. Then, moving the cap  6  downward, the pair of fitting protrusions  144  of each connector  5  is fitted in the corresponding pair of fitting recesses  182  of the cap  6  from therebelow. As a result, as shown in  FIG. 6 , the cap  6  is attached to the two connectors  5 , and the two connectors  5  are joined in the lateral direction. Attaching the cap  6  to the connectors  5  as described above, the assembled component of the connectors  5  and the cap  6  is completed. 
     In the middle of fitting between the fitting protrusions  144  and the fitting recesses  182 , the elastic piece  184  provided within the fitting recess  182  is pushed by the plate surface of the fitting protrusion  144  to elastically displace, and by the reaction force, the pressing protrusion  184 A presses the plate surface of the fitting protrusion  144 . As a result, by tightly pressing each fitting protrusion  144  with the reference surface  182 A of the fitting recess  182  and the elastic piece  184  of the cap  6  in the longitudinal direction of the connector  5 , it is possible to prevent unexpected coming off of the cap  6 . 
     Even in this embodiment, the form of positioning of each connector  5  in the longitudinal direction and the lateral direction of the connector in the middle of fitting between the fitting protrusions  144  and the fitting recesses  182  and in their fitting state is similar to that of the first embodiment. In other words, as shown in  FIG. 7 , by abutting the reference surfaces  144 A of the pair of fitting protrusions  144  to the reference surfaces  182 A of the pair of fitting recesses  182  in the longitudinal direction and abutting the reference surfaces  144 B and  144 C of the pair of fitting protrusions  144  to the reference surfaces  182 B and  182 C of the pair of fitting recesses  182  in the lateral direction, the connector  5  is positioned in the longitudinal direction and the lateral direction. 
     As described above, even in this embodiment, by cooperation of the pair of reference surfaces  144 A,  144 B,  144 C,  182 A,  182 B, and  182 C respectively, the connector is brought to regular position in the longitudinal direction and the lateral direction. 
     As described above, as a result of positioning each connector  5  in the longitudinal direction and the lateral direction by the two types of reference surfaces that are vertical to each other, the two pairs of the fitting recesses  182  of the cap  6  cooperate and the two pairs of the fitting protrusions  144  of the two connectors  5  cooperate, and thereby the specific positional relationship between the two connectors  5  can be maintained in the longitudinal direction and the lateral direction. 
     Similarly to the first embodiment, the connectors  5  are connected by soldering and implemented onto a corresponding circuit section on a circuit board while the cap  6  is being attached, and after completion of the implementation, the cap  6  will be removed and the connectors  5  are ready to fit to their mating connectors (not illustrated). 
     In addition, if the mating connector is provided with fitting recesses, each of which has the same shape as that of the fitting recess of the cap  6  so as to be able to fit to the fitting protrusion  144  of the connector  5 , it is possible to prevent increase of the size of the connector  5  and reduce the manufacturing cost similarly to the first embodiment. 
     The disclosure of Japanese Patent Application No. 2010-193319, filed on Aug. 31, 2010 is incorporated in the application by reference. 
     While the invention has been explained with reference to the specific embodiments of the invention, the explanation is illustrative and the invention is limited only by the appended claims.