Patent Publication Number: US-7217157-B2

Title: Waterproof connector

Description:
BACKGROUND OF THE INVENTION 
   Field of the Invention 
   This invention relates to a waterproof connector designed to meet a multi-pole design (due to the use of an increased number of circuits) and the use of terminals of different sizes (for a power system and a signal system), and more particularly to a structure for enhancing the ability to fill a sealing material in a connector housing. 
   There are already known various waterproof connectors (see, for example, JP-A-11-233225 Publication). 
   In a conventional waterproof connector, many wires pass through an internal space (hereinafter referred to as “sealing material-filling space”) of an outer housing in which the sealing material is filled. Particularly, a larger number of wires, extending respectively from the signal-system small terminals disposed at one side of the internal, pass through the one-side space as compared with the other-side space through which the power-system large terminals (disposed at the other-side of the internal) pass. 
   Therefore, there has been encountered a problem that the sealing material cannot be satisfactorily filled in the space through which the wires (extending respectively from the signal-system small terminals) pass. 
   And besides, the sealing material is filled in the sealing material-filling space by inserting the filling nozzle into the less densely-occupied space through which the wires, extending respectively from the power-system large terminals, pass. 
   Therefore, the filling of the sealing material in the space through which the wires (extending respectively from the signal-system small terminals) pass is effected after the filling of the sealing material in the space through which the wires (extending respectively from the power-system large terminals) pass is effected. Therefore, the sealing material-filling ability is worsened, and this has invited a problem that unfilled portions and residual bubbles develop. 
   SUMMARY OF THE INVENTION 
   This invention has been made in view of the above circumstances, and an object of the invention is to provide a waterproof connector in which the density of wires in an internal space of an outer housing, filled with a sealing material, is prevented from becoming uneven so that a sealing material can be filled uniformly in between the wires within the space, thereby enhancing the ability to fill the sealing material in the space. 
   (1) The invention provides a waterproof connector comprising: 
   an outer housing having an internal space, a first opening on a first side thereof and a second opening on a second side thereof; 
   an inner housing having a first and second areas in which different kinds of terminals are mounted, the inner housing being fitted to the first opening of the outer housing; 
   a waterproof plug through which a plurality of wires connected to the terminals pass in a sealing manner, the waterproof plug being fitted to the second opening; 
   a sealing material filled in the internal space of the outer housing between the inner housing and the waterproof plug; 
   wherein a centerline of the first opening and a centerline of the second opening are offset a predetermined amount from each other so that a density of the wires is made generally uniform in the internal space of the outer housing. 
   (2) The first opening may have a larger area than the second opening. 
   (3) An inclined surface may be formed on a predetermined portion of an inner surface of the outer housing in the internal space so as to oppose to the inner housing. 
   (4) The inclined surface may be formed on the second side of the outer housing. 
   In this waterproof connector, the outer housing is so formed that the centerline of the first opening and the centerline of the second opening are offset a predetermined amount from each other, and with this construction, the density of the wires in the internal space of the outer housing, filled with the sealing material, is made uniform, and there can be obtained the waterproof connector in which the ability to fill the sealing material in the space, as well as the efficiency of the filling operation, is excellent. 
   (5) A communication hole communicating the first opening of the outer housing with the internal space may be formed in the first area of the inner housing in which large-size terminals are mounted, and when the sealing material is filled in the internal space, a filling nozzle for supplying the sealing material may be inserted into the internal space through the communication hole. 
   (6) An inclined surface may be formed on a predetermined portion of an inner surface of the outer housing in the internal space so as to oppose to the inner housing, and 
   when the sealing material is filled in the internal space, the inclined surface may guide the sealing material from a filling nozzle inserted into the internal space through a communication hole formed in the inner housing. 
   In this waterproof connector, the filling nozzle for supplying the sealing material is inserted from the first opening of the outer housing into the space through the communication hole formed in the area of the inner housing in which the large-size terminals are mounted. Therefore, there can be obtained the waterproof connector in which the ability to fill the sealing material in the space, as well as the efficiency of the filling operation, is further enhanced. 
   (7) A guide groove may be formed in the inner surface of the outer housing over an entire periphery of the internal space, and when the sealing material is filled in the internal space, the sealing material may flow into the guide groove via the inclined surface; and 
   a plurality of notches may be formed in the guide groove portion, and may be disposed at predetermined intervals along the periphery of the guide groove, and the sealing material may be flowed from the guide groove via the notches toward the second side of said internal space. 
   In this waterproof connector, the inclined surface, the guide groove and the notches are provided in the sealing material-filling space within the outer housing, and therefore there can be obtained the waterproof connector in which the ability to smoothly and positively fill the sealing material from the filling nozzle in the space, as well as the ability to uniformly fill the sealing material, is secured. 
   In the waterproof connector of the present invention, the density of the wires in the sealing material-filling space within the outer housing can be made more uniform, and therefore the excellent ability to fill the sealing material in the space, as well as the high efficiency of the filling operation, can be secured. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a plan view of a first embodiment of a waterproof connector of the present invention. 
       FIG. 2  is a cross-sectional view taken along the line II—II of  FIG. 1 , showing a condition before a sealing material is filled in the waterproof connector of  FIG. 1 . 
       FIG. 3  is a perspective view of the waterproof connector of  FIG. 1  cut along the line III—III of  FIG. 2 . 
       FIG. 4  is a cross-sectional view taken along the line II—II in  FIG. 1 , showing a sealing material-filling operation in which a filling nozzle is inserted into the waterproof connector of  FIG. 2 . 
       FIG. 5  is a cross-sectional view taken along the line II—II in  FIG. 1 , showing a condition after the sealing material is filled in the waterproof connector of  FIG. 4 . 
       FIG. 6  is a plan view of a related-art waterproof connector. 
       FIG. 7  is a cross-sectional view of the waterproof connector taken along the line VII—VII of  FIG. 6 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 6  is a plan view of a related art waterproof connector that is developed previously from the claimed invention, and  FIG. 7  is a cross-sectional view of the waterproof connector taken along the line VII—VII of  FIG. 6 . 
   In the waterproof connector  100 , a sealing material (not shown) is filled in an internal space of an outer housing  110  lying between an inner housing  120  and a waterproof plug  130 , as shown in  FIGS. 6 and 7 . 
   The outer housing  110  has a connector opening  111  formed in one end portion thereof (upper portion in  FIG. 7 ), and also has a waterproof plug receiving portion  112  formed in the other end portion thereof (lower portion in  FIG. 7 ). The inner housing  120  is provided in the connector opening  111  of the outer housing  110 , and a plurality of kinds of terminals  150  and  151  of different sizes are mounted in an assorted manner in different areas of the inner housing  120  according to their size. Namely, the small-size terminals  150  for a signal system are mounted in the left-side area ( FIG. 7 ) disposed generally at the left side of a centerline of the inner housing  120 , while the large-size terminals  151  for a power system are mounted in the right area ( FIG. 7 ) disposed at the right side of the centerline of the inner housing  120 . 
   The waterproof plug  130  is fitted in the waterproof plug receiving portion  112  in the outer housing  110 , and wires  152 , extending respectively from the terminals  150  and  151  (mounted in the inner housing  120 ) toward the waterproof plug receiving portion  112  within the outer housing  110 , pass through the waterproof plug  130  to the exterior of the outer housing  110 . With the use of a filling nozzle (not shown), the sealing material is filled in the internal space of the outer housing  110  which lies between the inner housing  120  and the waterproof plug  130  and through which the wires  152  pass. 
   A preferred embodiment of the present invention will now be described with reference to the drawings. 
     FIG. 1  is a plan view of the first embodiment of a waterproof connector of the invention,  FIG. 2  is a cross-sectional view taken along the line II—II of  FIG. 1 , showing a condition before a sealing material is filled in the waterproof connector of  FIG. 1 ,  FIG. 3  is a perspective view of the waterproof connector of  FIG. 1  cut along the line III—III of  FIG. 2 ,  FIG. 4  is a cross-sectional view taken along the line II—II, showing a sealing material-filling operation in which a filling nozzle is inserted into the waterproof connector of  FIG. 2 , and  FIG. 5  is a cross-sectional view taken along the line II—II, showing a condition after the sealing material is filled in the waterproof connector of  FIG. 4 . 
   Referring to  FIGS. 1 to 5 , in the waterproof connector  10 , the sealing material  50  (see  FIG. 5 ) is filled in an internal space of an outer housing  20  lying between an inner housing  30  and a waterproof plug  40 . 
   The outer housing  20  has a connector opening  21  (first opening of the invention) formed in one end portion thereof (upper portion in  FIG. 2 ), and also has a waterproof plug receiving portion  22  (second opening of the invention) formed in the other end portion thereof (lower portion in  FIG. 2 ). 
   The inner housing  30  is provided in the connector opening  21  of the outer housing  20 , and a plurality of kinds of terminals  1  and  2  of different sizes are mounted in an assorted manner in different areas of the inner housing  30  according to their size. Namely, the small-size terminals  1  for a signal system (hereinafter referred to as “signal-system small terminals”) are mounted in the left-side area ( FIG. 2 ) disposed generally at the left side of a centerline of the inner housing  30 , while the large-size terminals  2  for a power system (hereinafter referred to as “power-system large terminals”) are mounted in the right area ( FIG. 7 ) disposed at the right side of the centerline of the inner housing  30 . 
   The waterproof plug  40  is fitted in the waterproof plug receiving portion  22  in the outer housing  20 , and wires  3 , extending respectively from the terminals  1  and  2  (mounted in the inner housing  30 ) toward the waterproof plug receiving portion  22  (that is, downward in  FIG. 2 ) within the outer housing  20 , pass through the waterproof plug  40  to the exterior of the outer housing  20 . 
   With the use of the filling nozzle  4  ( FIG. 4 ), the sealing material  50  is filled in the internal space of the outer housing  20  which lies between the inner housing  30  and the waterproof plug  40  and through which the wires  3  pass. 
   The outer housing  20  is so formed that a centerline α 1  of the connector opening  21  and a centerline α 2  of the waterproof plug receiving portion  22  are offset a predetermined amount from each other. Because of this offset arrangement, the centerline of the inner housing  30 , provided in the connector opening  21 , and a centerline of the waterproof plug  40 , fitted in the waterproof plug receiving portion  22 , are offset from each other by an amount equal to the above offset amount in the same direction as the direction of offset of the centerlines α 1  and α 2 . With this construction, the density of the wires  3  in the space (hereinafter referred to as “sealing material-filling space  23 ”) to be filled with the sealing material  50  is made generally uniform. 
   A filling guide surface  24  (inclined surface of the invention) is formed on a predetermined portion of an inner surface of the outer housing  20  exposed to the sealing material-filling space  23 . When the sealing material  50  is poured into the sealing material-filling space  23 , the filling guide surface  24  receives the sealing material  50  from the filling nozzle  4  inserted into the sealing material-filling space  23  through a communication hole  31  (described later) formed in the inner housing  30 . 
   Further, a guide groove  25  is formed in the inner surface of the outer housing  20  over an entire periphery of the sealing material-filling space  23 . When the sealing material  50  is poured into the sealing material-filling space  23 , the sealing material  50  flows into the guide groove  25  via the filling guide surface  24 . 
   A plurality of notches  26  are formed in the guide groove portion  25 , and are disposed at predetermined intervals in the direction of the periphery of the guide groove  25 . The sealing material  50 , poured from the filling nozzle  4  into the guide groove  25  via the filling guide surface  24 , is flowed from the guide groove  25  via the notches  26  toward that portion of the sealing material-filling space  23  disposed close to the waterproof plug  40  (that is, downward in  FIG. 2 ). 
   The communication hole  31 , communicating the connector opening  21  of the outer housing  20  with the sealing material-filling space  23 , is formed in the area of the inner housing  30  in which the power-system large terminals  2  are mounted. When the sealing material  50  is to be filled in the sealing material-filling space  23 , the filling nozzle  4  for supplying the sealing material  50  is inserted from the connector opening  21  of the outer housing  20  into the sealing material-filling space  23  through the communication hole  31  (that is, inserted downward from the upper side in  FIG. 2 ). 
   Next, the operation of this embodiment will be described. 
   In the above waterproof connector  10 , when the sealing material  50  is to be filled in the sealing material-filling space  23 , the filling nozzle  4  is inserted from the connector opening  21  of the outer housing  20  into the sealing material-filling space  23  through the communication hole  31  (that is, inserted downward from the upper side in  FIG. 4 ) in the inner housing  30 , as shown in  FIG. 4 . In this condition, the sealing material  50 , supplied from the filling nozzle  4 , is smoothly and positively filled in the sealing material-filling space  23  via the filling guide surface  24 , the guide groove  25  and the notches  26  in the guide groove portion  25 . 
   Namely, the sealing material  50  from the filling nozzle  4  flows into the guide groove  25  via the filling guide surface  24 , and is filled in this guide groove  25  over the entire periphery thereof, and thereafter the sealing material  50  drops through the notches  26  of the guide groove portion  25  into that portion (lower portion in  FIG. 2 ) of the sealing material-filling space  23  disposed close to the waterproof plug  40 . Then, the sealing material  50  is uniformly filled in the sealing material-filling space  23  in such a manner that the level of this filled sealing material  50  gradually rises from the upper surface of the waterproof plug  40 . 
   Here, the density of the wires  3  in the sealing material-filling space  23  is generally uniform since the centerline α 1  of the connector opening  21  of the outer housing  20  and the centerline α 2  of the waterproof plug receiving portion  22  are offset from each other. Therefore, in the above filling operation, the sealing material  50  is uniformly filled in between the wires  3  within the sealing material-filling space  23 . As a result, the enhanced ability to fill the sealing material  50  in the sealing material-filling space  23  is secured. 
   As described above, in the above embodiment, the density of the wires  3  in the sealing material-filling space  23  within the outer housing  20  can be prevented from becoming uneven, and the sealing material  50  can be filled uniformly in between the wires  3  within the sealing material-filling space  23 . Therefore, the ability to fill the sealing material  50  in the sealing material-filling space  23 , as well as the efficiency of the filling operation, can be enhanced, and the development of unfilled portions and residual bubbles can be suppressed. And besides, the efficiency of the operation for passing the wires through the waterproof plug  40  can be enhanced. 
   Furthermore, the communication hole  31  in the inner housing  30  is provided in the area where the power-system large terminals  2  are mounted, that is, the less densely-occupied area as compared with the area where the signal-system small terminals  1  are mounted. Therefore, the efficiency of the operation for filling the sealing material  50  in the sealing material-filling space  23  can be further enhanced, and also the sealing material  50  can be filled more uniformly in between the wires  3  within the sealing material-filling space  23 . 
   Furthermore, the filling guide surface  24 , the guide groove  25  and the notches  26  are provided in the sealing material-filling space  23  within the outer housing  20 , and therefore the sealing material  50  from the filling nozzle  4  can be positively flowed into the guide groove  25  via the filling guide surface  24 , and can be smoothly flowed via the notches  25  into that portion of the sealing material-filling space  23  disposed close to the waterproof plug  40 . Therefore, the ability to smoothly and positively fill the sealing material  50  from the filling nozzle  4  in the sealing material-filling space  23 , as well as the ability to uniformly fill the sealing material, can be secured. Therefore, the sealing material  50  can be filled more uniformly in between the wires  3  within the sealing material-filling space  23 , and also the efficiency of the operation for filling the sealing material  50  in the sealing material-filling space  23  can be further enhanced. 
   The waterproof connector of the present invention can be suitably used as a waterproof connector designed to meet a multi-pole design (due to the use of an increased number of circuits) and the use of terminals of different sizes (for a power system and a signal system), and more particularly the structure of the invention can be suitably used at those portions of such a waterproof connector requiring a waterproof ability.