Patent Publication Number: US-6659810-B2

Title: Method of assembling multi-pole connector and multi-pole connector

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to a multi-pole connector connected to a mating multi-pole connector by a bolt-and-nut construction to provide a connector, and more particularly to a method of assembling the multi-pole connector, formed by combining a plurality of connector housings together, and to such a multi-pole connector. 
     One known conventional multi-pole connector is disclosed in JP-A-62-145671. Referring to FIG. 9, for the purpose of enhancing the productivity, the multi-pole connector  101  is formed by combining a plurality of (for example, three) connector housings  103 A,  103 B and  103 C together. 
     A nut  105  is formed at a central portion of the connector housing  103 A, and fitting openings  107  and  109  for respectively receiving the connector housings  103 B and  103 C are formed in upper and lower portions of the connector housing  103 A, respectively. Elastic retaining arms  111  are formed respectively on side walls of each of the fitting openings  107  and  109 , and can be lockingly engaged respectively in retaining grooves  113  formed respectively in side walls of the corresponding connector housing  103 B,  103 C. 
     The connector housing  103 B and the connector housing  103 C are slidingly inserted respectively into the upper and lower portions of the connector housing  103 A, and therefore are combined with the connector housing  103 A, and then comb-like rear holders  115  and  117  are inserted through the side surfaces in order to prevent the rearward withdrawal of these connector housings  103 B and  103 C. Thus, the multi-pole connector  101  is assembled. 
     The thus assembled multi-pole connector  101  is fittingly connected to a mating multi-pole connector  123  (shown in FIG. 11) by the nut  105 , formed on the multi-pole connector  101 , and a bolt  121 , formed on the mating multi-pole connector, to form a connector. 
     In the above conventional construction, however, when determining the pitches of the connector housings  103 A,  103 B and  103 C, the nut  105  is used as a reference. Therefore, when determining the pitch, for example, of the connector housing  103 B, an error a in the pitch A of the connector housing  103 A from the nut  105  to the mounting position of the connector housing B and an error b in the pitch B of the connector housing  103 B are added together in an accumulated manner as shown in FIG. 12, and the sum of these errors become an error in the pitch of the connector housing  103 B. Therefore, there is encountered a problem that an error in the connector housing  103 B, which is the combining portion, increases. Similarly, an error in the connector housing  103 A and an error in the connector housing  103 B are added together in an accumulated manner, so that the total error for the connector housing  103 C increases. 
     SUMMARY OF THE INVENTION 
     With the above problem of the conventional construction in view, it is an object of this invention to provide a method of assembling a multi-pole connector, as well as a multi-pole connector, in which in order that an error in the multi-pole connector, formed by combining a plurality of connector housings together, can be reduced, the alignment of the connector housings can be effected easily and accurately. 
     In order to solve the aforesaid object, the invention is characterized by having the following arrangement. 
     (1) A multi-pole connector comprising: 
     a first connector housing including a bolt and a bolt receiving tube; and 
     a second connector housing including a frame portion, 
     wherein the first and second connector housings are connected together so as to coaxially superimpose the frame portion on the bolt receiving tube so that a bolt guide formed on a mating multi-pole connector for connection to the multi-pole connector can be inserted into the frame portion and the bolt receiving tube. 
     (2) The multi-pole connector according to (1), wherein the first connector housing and the second connector housing have a connecting mechanism for connecting the first connector housing to the second connector housing before the bolt guide is inserted into the frame portion and the bolt receiving tube. 
     ( 3 ) The multi-pole connector according to ( 1 ), wherein a plurality of the second connector housings are connected to the first connector housing, and each of the frame portions of the plurality of the second connector housings is coaxially superimposed on the bolt receiving tube. 
     ( 4 ) A method of assembling a multi-pole connector comprising a first connector housing including a bolt and a bolt receiving tube, and a second connector housing including a frame portion, the method comprising the steps of: 
     connecting the first connector housing to the second connector housing so as to coaxially superimpose the frame portion on the bolt receiving tube; and 
     inserting a bolt guide formed on a mating multi-pole connector for connection to the multi-pole connector into the frame portion and the bolt receiving tube. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a multi-pole connector of the present invention. 
     FIG. 2 is a front-elevational view as seen from a direction II of FIG.  1 . 
     FIG. 3 is a plan view as seen from a direction III of FIG.  1 . 
     FIG. 4 is a perspective view showing a bolt guide of a mating multi-pole connector and an important portion of the multi-pole connector. 
     FIG. 5 is a view explanatory of a pitch determined using a nut as a reference. 
     FIG. 6 is a perspective view of another embodiment of a multi-pole connector of the invention. 
     FIG. 7 is a front-elevational view as seen from a direction VII of FIG.  6 . 
     FIG. 8 is a plan view as seen from a direction VIII of FIG.  6 . 
     FIG. 9 is an exploded, perspective view of a conventional multi-pole connector. 
     FIG. 10 is a perspective view of the conventional multi-pole connector in its assembled condition. 
     FIG. 11 is a perspective view of a conventional mating multi-pole connector. 
     FIG. 12 is a front-elevational view as seen from a direction IX of FIG. 10, explaining pitches. 
     FIG. 13 is a front elevational view of a non-limiting embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     A preferred embodiment of the present invention will now be described in detail with reference to the drawings. FIGS. 1 to  3  show a multi-pole connector  1  of the present invention. The multi-pole connector  1  comprises a first connector housing  3 , and a second connector housing  5  connected to and combined with the first connector housing  3 . 
     Referring to FIG. 4, a bolt guide  9  is formed on a mating multi-pole connector  7  (details are omitted) which is to be connected to the multi-pole connector  1 , and a nut  8  is formed in the bolt guide  9 . A bolt receiving tube  11  is formed at the first connector housing  3  of the multi-pole connector  1 , and a bolt  15  is provided within the bolt receiving tube  11  at a central portion thereof, and this bolt  15  can be threaded into the nut  8  in the bolt guide  9 . The bolt receiving tube  11  has generally the same cross-sectional shape as the cross-sectional shape (for example, a square cross-sectional shape) of the bolt guide  9 . 
     Many cavities  17  are provided in those portions of the first connector housing  3  and disposed respectively above and below the bolt receiving tube  11 . Fitting recess portions  19 , serving as a connecting mechanism, are provided at upper and lower surfaces of the first connector housing  3 , respectively. An engagement projection  21  for being engaged with the second connector housing  5  at the time of the combining operation is formed at a central portion of a front portion (left-hand portion in FIG. 1) of each fitting recess portion  19 . 
     A frame portion  23  is formed on a central portion of a right side surface (see FIG. 1) of the second connector housing  5 , and projects toward the first connector housing  3 . At the time of the combining operation, the frame portion  23  is superimposed on the bolt receiving tube  11  in coaxial relation thereto. The inner surface of the frame portion  23  is generally identical in shape to the outer surface of the bolt guide  9  and the inner surface of the bolt receiving tube  11 . Mounting arms  25 , so shaped as to fit respectively in the fitting recess portions  19  formed in the first connector housing  3 , are formed respectively on the upper and lower sides of the second connector housing  5 , and project in the same direction as the direction of projecting of the frame portion  23 . Each of the mounting arms  25  has an engagement portion  27  for engagement with the engagement projection  21  provided at the corresponding fitting recess portion  19 . 
     Then, the bolt guide  9  of the mating multi-pole connector  7  is passed through the frame portion  23  (superimposed on the bolt receiving tube  11 ), and is inserted into the bolt receiving tube  11  of the multi-pole connector  1 , and the frame portion  23  and the bolt receiving tube  11  are aligned with each other (that is, positioned relative to each other) by inserting this bolt guide  9 , so that the first connector housing  3  and the second connector housing  5  are combined together. At the same time, the bolt  15  of the multi-pole connector  1  is threaded into the nut  8 , formed in the bolt guide  9  of the mating multi-pole connector  7 , so that the multi-pole connector  1  and the mating multi-pole connector  7  are connected together. 
     As described above, when connecting the multi-pole connector  1  and the mating multi-pole connector  7  together, the first connector housing  3  and the second connector housing  5  of the multi-pole connector  1  are brought into alignment with each other by the bolt guide  9  of the mating multi-pole connector  7 , and therefore dimensions A 1  and A 2  from the center CL of the nut  8  can be obtained as shown in FIG.  5 . Therefore, tolerances of the cavities  17  are equal to tolerances of the dimensions A 1  and A 2 , and an accumulated error is prevented from developing also in the second connector housing  5 . 
     The present invention is not limited to the above embodiment, and other form of the invention can be carried out by suitable modifications. More specifically, in the above embodiment of the invention, although the frame portion  23 , which is superimposed on the bolt receiving tube  11  of the first connector housing  3  in coaxial relation thereto, is formed on and projects from the second connector housing  5 , a frame portion  33  may be formed at a portion of the second connector housing  31  as in a multi-pole connector  29  shown in FIGS. 6 to  8 . 
     Guide rails  35  for connection to first connector housing  37  are formed on a side surface of the second connector housing  31  disposed above the frame portion  33 , and rail grooves  36  are formed in a side surface of the first connector housing  37  disposed above a bolt receiving chamber. The guide rails  35  are slidably connected respectively to the rail grooves  36  for upward and downward movement as indicated by an arrow, and by doing so, the first connector housing  37  and the second connector housing  31  are connected together. As a result, a bolt receiving tube  11  of the first connector housing  37  is superimposed on the frame portion  33  of the second connector housing  31  in coaxial relation thereto. In this case, also, similar effects as described above can be obtained. Those portions, corresponding respectively to those of the preceding embodiment, are designated by identical reference numerals, respectively, and repeated explanation thereof is omitted here. 
     In the above embodiments of the invention, although the second connector housing  5 ,  31  is combined with the first connector housing  3 ,  37  of the multi-pole connector  1 ,  29 , two or more other connector housings (second connector housing) can be combined with the first connector housing  3 ,  37 . In this case, a frame portion is formed on each of the two or more other connector housings, and all of these frames are superimposed on the bolt receiving tube of the first connector housing in coaxial relation thereto (as shown in FIG.  13 ). 
     As described above, in the multi-pole connector-assembling method of the invention and the multi-pole connector of the invention, the fitting of the multi-pole connector relative to the mating multi-pole connector can be effected simultaneously with the alignment of the first connector housing relative to the second connector housing. And besides, similarly with the alignment of the first connector housing, the alignment of the second connector housing can be effected through the bolt, using the nut as a reference, and therefore the accumulation of errors is prevented, and the error can be kept to a minimum.