Patent Publication Number: US-6336831-B1

Title: Combined connector

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a combined connector in which a plurality of connector housings each including a plurality of terminal storage chambers can be simply connected together in a multiple-stage manner. 
     2. Description of the Related Art 
     As a combined connector of this type, there is known a combined connector which is disclosed in Japanese Patent Unexamined Publication No. Hei. 2-223171 and shown in FIGS.  4 ( a ) to  4 ( c ). This conventional combined connector  1 , as shown in FIGS.  4 ( a ) and  4 ( c ), is composed of a connector housing  2  arranged on the lower-most stage side, connector housings  2 ′ and  2 ′ respectively arranged on the middle stage side and the upper-most stage side, and a cover  8  for covering an opening  3   a  formed in the connector housing  2 ′ arranged on the upper-most stage side. In the respective connector housings  2 ,  2 ′ and  2 ′, there are formed a plurality of terminal storage chambers  3   b  for storing therein terminals (not shown). Also, in the front and rear portions of the two side walls  3  and  3  of each of the connector housings  2 ,  2 ′ and  2 ′, there are provided a pair of triangular-prism-shaped, upwardly located, provisionally securing projection  4  and, downwardly located, finally securing projection  5  in such a manner that they are respectively formed integrally with the side walls  3  and projected therefrom; and, on the opening  3   a  sides of the two side walls  3 ,  3 , there are provided a pair of triangular-prism-shaped, right and left cover securing projections  6  and  6  formed integrally with and projectingly from the side walls  3 , with the provisionally and finally securing projections  4  and  5  located between them. 
     As shown in FIGS.  4 ( a ),  4 ( b ) and  4 ( c ), at the positions of the two side walls  3  and  3  of the connector housings  2 ′ and  2 ′ respectively arranged on the middle and upper-most stage sides, in particular that are respectively opposed to the above-mentioned respective securing projections  4  and  5 , there are provided frame-shaped engaging pieces  7  and  7  in such a manner that they are formed integrally with their respective side walls  3  and are projected therefrom. Also, at the positions of the two side portions of the cover  8  that are respectively opposed to the above-mentioned respective securing projections  6 , there are provided frame-shaped engaging pieces  9  in such a manner that they are formed integrally with their respective side portions and are projected therefrom. By pressing down the connector housing  2 ′ on the upper-most stage side, as shown in FIG.  4 ( c ), the combined connector  1  can be assembled. That is, as shown by two-dot chained lines in FIG.  4 ( b ), the engaging pieces  7  are respectively fitted with the finally securing projections  5 , and the engaging pieces  9  of the cover  8  are slidingly fitted with the cover securing projections  6 , respectively. This completes such assembly of the combined connector  1  as shown in FIG.  4 ( c ). By the way, a similar technology relating to the combined connector  1  is disclosed in FIG. 2 in Japanese Patent Unexamined Publication No. Hei. 4-39822. 
     However, in the above-mentioned conventional combined connector  1 , when the respective connector housings  2 ,  2 ′ and  2 ′ are connected together (combined together), it is difficult to position them (that is, to match the centers thereof with each other): that is, as shown in FIG. 5, when the positions of the engaging pieces  7  are shifted in the right and left directions and, as shown in FIG. 6, when the positions of the engaging pieces  7  are shifted in the back and forth directions, it is difficult to pile up the respective connector housings  2 ,  2 ′ and  2 ′ on top of another and secure them to one another. Also, the piling-up and engaging forces of the respective connector housings  2 ,  2 ′ and  2 ′ are easy to vary and, even after they are combined together, there is a fear that there can be produced a clearance between the respective connector housings  2 ,  2 ′ and  2 ′ due to the insufficient piling-up and engaging forces. 
     SUMMARY OF THE INVENTION 
     In view of the above-mentioned circumstances, the present invention aims at eliminating the above-mentioned drawbacks found in the conventional combined connectors. Accordingly, it is an object of the invention to provide a combined connector which can prevent the respective connector housings from shifting in position in the back and forth directions and in the right and left directions when they are combined together, can reduce the variations in the engaging forces necessary for fitting engagement between the respective securing projections and engaging recessed portions, and can prevent production of a clearance between the respective connector housings after they are combined together. 
     In attaining the above object, according to the invention, there is provided a combined connector comprising: a plurality of connector housings each including a plurality of terminal storage chambers therein, the connector housings being piled up on top of another and secured to one another in multiple stages in their connecting direction; a first securing projecting portion which is provided in one of mutually opposing connector housings arranged in the connecting direction; a first securing recessed portion which is provided in the other of the mutually opposing connector housings and into which the first securing projecting portion is fitted; a second securing projecting portion which is provided in the one connector housing in a direction crossing at right angles to the first securing projecting and recessed portions; a second securing recessed portion which is provided in the other connector housing and into which the second securing projecting portion is fitted; and an introducing portion which is provided in at least one of the first and second securing projecting portions. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a first embodiment of a combined connector according to the invention, showing a state thereof before it is combined; 
     FIG. 2 is an enlarged perspective view of the main portions of a connector housing arranged on the upper stage side of the combined connector, when they are viewed from the bottom surface side of the combined connector; 
     FIG. 3 is an enlarged perspective view of the main portions of a connector housing arranged on the lower stage side of the combined connector; 
     FIG.  4 ( a ) is an exploded perspective view of a conventional combined connector; 
     FIG.  4 ( b ) is an enlarged perspective view of securing means used in the conventional combined connector; 
     FIG.  4 ( c ) is a perspective view of the conventional combined connector, showing a state thereof in which it is combined; 
     FIG. 5 is a partially perspective view of the securing means used in the conventional combined connector, showing a state thereof in which the engaging piece side thereof is shifted in the right and left directions to thereby unable to pile up the connector housings one on top of another; and 
     FIG. 6 is a partially perspective view of the securing means used in the conventional combined connector, showing a state thereof in which the engaging piece side thereof is shifted in the back and forth directions to thereby unable to pile up the connector housings one on top of another. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Now, description will be given below of an embodiment of a combined connector according to the invention with reference to the accompanying drawings. 
     In particular, FIG. 1 is a perspective view of the embodiment of a combined connector according to the invention, showing a state thereof before it is combined; FIG. 2 is an enlarged perspective view of the main portions of a connector housing arranged on the upper stage side of the combined connector, when they are viewed from the bottom surface side of the combined connector; and FIG. 3 is an enlarged perspective view of the main portions of a connector housing arranged on the lower stage side of the combined connector. 
     As shown in FIG. 1, a combined connector  10  comprises an upper stage side connector housing (one connector housing)  20  including a plurality of terminal storage chambers  21 , a lower stage side connector housing (the other connector housing)  30  which includes a plurality of terminal storage chambers  31  and can be piled up onto and secured to the upper stage side connector housing  20 , and a synthetic resin cover  40  which is disposed integrally with the lower stage side connector housing  30  through a hinge portion and a band portion (neither of which are shown) and is used to close an opening  31   a  side of the terminal storage chambers  31 . 
     The upper stage side connector housing  20  is formed of synthetic resin in a substantially box-like shape and, between the front and rear end portions of the connector housing  20 , there are formed, in parallel, a plurality of terminal storage chambers  21 . The rear portion of a bottom surface  20   a  of the upper stage side connector housing  20  is formed as an opening  21   a  which is used to expose part of a terminal (not shown) stored in each of the terminal storage chambers  21  and one end side of an electric wire W connected to the present terminal. Also, as shown in FIGS. 1 and 2, in the central portion of the bottom surface  20   a  of the upper stage side connector housing  20 , as well as on the two sides of the central portion, there are formed integrally and projectingly first securing projecting portions  22  each having a substantially trapezoidal section in such a manner that they extend in the longitudinal direction of the connector housing  20  and in parallel to one another. Further, formed on bottom surface  20   a  are second securing projecting portions  23  each having a substantially L-shaped front surface section. These second securing projecting portions  23  are formed at two end portions of the bottom surface  20   a  of the upper stage side connector housing  20  and in the front side portions of the two side surfaces  20   b  and  20   b  and extend at right angles to the first securing projecting portions  22 . 
     As shown in FIGS. 1 and 2, each of the pair of right and left second securing projecting portions  23  and  23  includes a substantially tongue-shaped (substantially semi-disk-shaped) introducing portion or introducing rib  23   a  which is formed integrally with and is projected downward from the lower portion of the projecting portion  23  in such a manner that it is flush with the side surface  20   b.  Introducing tapered projecting portion  23   b,  which formed integrally with and projects from the leading end side of the circular portion of the introducing rib  23   a  in such a manner that it is inclined. A flat projecting portion  23   c  having a box-like shape, projects from the introducing tapered projecting portion  23   b  to the bottom surface  20   a  of the upper stage side connector housing  20 . Also, in the respective rear portions of the two side surfaces  20   b  and  20   b  of the upper stage side connector housing  20 , are triangular-prism-shaped projections (securing portions)  24  disposed in such a manner that they are formed integrally therewith and are projected therefrom. Further, in the central portion of the upper surface  20   c  of the upper stage side connector housing  20 , there is integrally and projectingly provided a flexible lock arm  25  which can be secured to and removed from a mating connector (not shown). 
     The lower stage side connector housing  30  is formed of synthetic resin in a substantially box-like shape and, between the front and rear end portions of the connector housing  30 , there are formed, in parallel a plurality of terminal storage chambers  31 . The rear portion of a bottom surface  30   a  of the lower stage side connector housing  30  is formed as an opening  31   a  which is used to expose part of a terminal (not shown) stored in each of the terminal storage chambers  31  and one end side of an electric wire W connected to the present terminal. Also, as shown in FIGS. 1 and 2, in the central portion of an upper surface  30   c  of the lower stage side connector housing  30  as well as on the two sides of the central portion, there are formed first securing recessed portions  32  each having a substantially inverted trapezoidal section in such a manner that they extend in the longitudinal direction of the connector housing  30  and in parallel to one another, so that the first securing projecting portions  22  of the upper stage side connector housing  20  can be respectively fitted with the first securing recessed portions  32 . Further, at the positions of the connector housing  30  that not only exist in the two end portions of the upper surface  30   c  of the lower stage side connector housing  30  and in the front side portions of the two side surfaces  30   b  and  30   b  but also extend in a direction crossing at right angles to the first securing recessed portions  32 , there are formed second securing recessed portions  33  each having a substantially L-shaped front surface section. Thus, the second securing projecting portions  23  of the upper stage side connector housing  20  can be respectively fitted with the second securing recessed portions  33  of the lower stage side connector housing  30 . 
     As shown in FIGS. 1 and 3, each of the pair of right and left second securing recessed portions  33  and  33  includes a guiding tapered recessed portion  33   b  into which its associated introducing rib  23   a  and introducing tapered projecting portion  23   b  can be inserted, and a horizontal recessed portion  33   c  into which its associated flat projecting portion  23   c  can be inserted. Also, in the respective rear portions of the two side surfaces  30   b  and  30   b  of the lower stage side connector housing  30 , there are provided integrally and projectingly frame-shaped engaging pieces (engaging portions)  34  each having a rectangular-shaped engaging hole  34   a  to which its associated projection  24  of the upper stage side connector housing  20  can be secured; and, at the same time, in the respective lower portions of the engaging pieces  34 , there are provided integrally and projectingly triangular-prism-shaped projections (securing portions)  35 . Further, in the rear portion of the upper surface  30   c  of the lower stage side connector housing  30 , there is provided integrally and projectingly a wire hold portion  36  which is used to close the opening  21   a  of the upper stage side connector housing  20 . 
     As shown in FIG. 1, before the upper and lower stage side connector housings  20  and  30  are connected together (combined together), the cover  40  is disposed integrally with the bottom surface  30   a  of the lower stage side connector housing  30  through a hinge portion and a band portion (neither of which are shown) and, after combined together, the band portion is cut off and is then moved through the hinge portion to the opening  31   a  side of the terminal storage chamber  31  to thereby close the opening  31   a.  In this closing operation, frame-shaped engaging pieces (engaging portions)  44 , which are respectively provided in the rear portions of the two side portions of the cover  40  formed of synthetic resin and include rectangular-shaped engaging holes  44   a,  are secured to the triangular-prism-shaped projections  35  provided in the rear portions of the two side surfaces  30   b  and  30   b  of the lower stage side connector housing  30 . 
     According to the combined connector  10  structured in accordance with the above-mentioned embodiment, when the upper and lower stage side connector housings  20  and  30  are piled up and combined together, the first securing projecting portions  22  and second securing projecting portions  23  of the upper stage side connector housing  20  are respectively fitted into the first securing recessed portions  32  and second securing recessed portions  33  of the lower stage side connector housing  30 . In this combining operation, when the upper and lower stage side connector housings  20  and  30  are shifted in the back and forth directions from each other, the circular portions of the leading end portions of the introducing ribs  23   a  of the second securing projecting portions  23  provided on the two side portions of the upper stage side connector housing  20  are respectively inserted into the second securing recessed portions  33  of the lower stage side connector housing  30  to thereby match the centers of the upper and lower stage side connector housings  20  and  30  with each other. Also, when the upper and lower stage side connector housings  20  and  30  are shifted in the right and left directions from each other, the introducing tapered projecting portions  23   b  of the second securing projecting portions  23  provided on the two side portions of the upper stage side connector housing  20  are guided and inserted into the guiding tapered recessed portions  33   b  of the second securing recessed portions  33  formed in the lower stage side connector housing  30  to thereby match the centers of the upper and lower stage side connector housings  20  and  30  with each other. Due to this, the centers of the upper and lower stage side connector housings  20  and  30  can be matched with each other to thereby be able to correct simply the positional difference between the upper and lower stage side connector housings  20  and  30  in the back and forth directions thereof as well as in the right and left directions thereof, so that the upper and lower stage side connector housings  20  and  30  can be combined together simply and positively. 
     In this manner, since the positional difference between the upper and lower stage side connector housings  20  and  30  in the back and forth directions thereof as well as in the right and left directions thereof can be prevented when they are combined together, the respective connector housings  20  and  30  can be positioned easily and positively. Also, the variations in the engaging or fitting forces of the first and second securing projecting portions  22  and  23  as well as the first and second securing recessed portions  32  and  33  to be engaged with the first and second securing projecting portions  22  and  23  can be reduced as much as possible, which makes it possible to prevent a clearance from being produced between the respective connector housings  20  and  30  after they are combined together. Further, the fitting engagement between the respective connector housings  20  and  30  by means of the fitting engagement between the first and second securing recessed portions  32 ,  33  and the first and second securing projecting portions  22 ,  23  can be reinforced further by the fitting engagement between the projections  24  of the upper stage side connector housing  20  and the engaging holes  34   a  of the engaging pieces  34  of the lower stage side connector housing  30 , so that the variations in the engaging force between the respective connector housings  20  and  30  as well as the generation of the clearance between them can be prevented positively. 
     By the way, in the above-mentioned embodiment, description has been given of the combined connector structured such that the connector housings are piled up and secured together in two stages, that is, in the upper and lower stages. However, this is not limitative but, of course, the above-mentioned embodiment can also apply to a combined connector structured such that the connector housings are piled up and secured together in three or more stages. 
     As has been described heretofore, according to the invention, the positional difference between the upper and lower stage side connector housings in the back and forth directions thereof as well as in the right and left directions thereof can be prevented when they are combined together, so that the respective connector housings can be positioned easily and positively. Also, the variations in the engaging or fitting forces between the first and second securing projecting portions and the first and second securing recessed portions can be reduced as much as possible, which makes it possible to prevent a clearance from being produced between the respective connector housings after they are combined together.