Abstract:
The object of the invention is to provide a connector assembly having enough waterproof performance, without needing high insertion force during the assembly process. In accordance with the present invention, there is provided a connector assembly  1  comprising a plug assembly  7;  a header assembly  5  configured to be mated with the plug assembly  7  while forming an opening between the plug assembly  7  and the inside of the header assembly  5;  holder assemblies  18   d  and  18   e  configured to apply pressure on the plug assembly in the direction of insertion of the plug assembly  7  into the header assembly  5;  and a sealing member  4  configured to be pushed out toward the opening in response to the pressure applied by the holder assemblies  18   d  and  18   e  after insertion of the plug assembly  7  into the header assembly  5,  in order to plug and seal the opening.

Description:
BACKGROUND OF THE INVENTION 
   (1) Field of the Invention 
   The present invention relates to a connector assembly. In particular, the present invention relates to a connector assembly having enhanced sealing performance between a plug assembly and a header assembly. 
   (2) Description of the Related Art 
   Various electronic components are mounted on an automobile, which is provided with a wiring harness for transmitting electric power or control signals to the electronic devices. The afore-mentioned wiring harness includes one or more electrical wires and connector assemblies. Conventionally, the electrical wire comprises an electrically conductive core wire and an electrically insulating outer layer. 
   As the connector as described above, for example, a connector assembly disclosed in Japanese Published Patent Application No. 2000-294336 can be used. Such a connector assembly includes a connector housing and a sealing member. The connector housing in turn includes a tubular outer case and a plurality of plate-like housings, which are provided with a terminal receiving groove for receiving a terminal fitting attached to an electrical wire. 
   The sealing member includes a plurality of sheet-like sealing pieces, each made of resilient materials such as rubber. The sheet-like sealing piece is attached to the plate-like housing so as to provide a seal for moisture around the electrical wire which is attached to the terminal fitting received in the terminal receiving groove of the plate-like housing. 
   The connector as described above can be assembled as follows. First, the terminal fitting attached to the electrical wire is received in the terminal receiving groove of the plate-like housing, and the sheet-like sealing pieces are attached to the plate-like housing. Thereafter, the plate-like housings are engaged with each other and then the same plate-like housings are received in an outer case. Finally, the resulting connector as mentioned above is coupled to a mating connector. During the connector as mentioned above, the sheet-like sealing pieces protect the electrical wire against moisture so as to prevent moisture and the like from entering the terminal receiving groove via the electrical wire. 
   During the above referenced connector, while the sheet-like sealing pieces, each made of rubber and the like having restitution property, are used in order to ensure that moisture does not pass into both the outer case and the housing, a drawback of the connector is that more force is needed to insert the housing into the outer case. In other word, difficulty of insertion operation as mentioned above is problematic. One proposed method of overcoming the high insertion force was to control restitution property of the sealing piece. Unfortunately, in such a case, it was found to be impossible to provide a connector assembly with enough waterproof performance. 
   Thus, a need exists for an improved electrical connector assembly, which has enough waterproof performance, as well as, does not need high insertion force when the housing is mated into the outer case. 
   SUMMARY OF THE INVENTION 
   In accordance with an embodiment of the present invention, a connector assembly comprises a plug assembly; a header assembly configured to be mated with the plug assembly while forming an opening between the plug assembly and the inside of the header assembly; a holder configured to be pressed in the direction of insertion of the plug assembly into the header assembly; and a sealing member configured to be pushed out in a direction to fill the opening in response to the pressure applied by the holder after insertion of the plug assembly into the header assembly, in order to plug and seal the opening. 
   During the afore-mentioned connector assembly, the plug assembly is mated with the header assembly, while forming the opening between the plug assembly and the inside of the header assembly. Thereafter, the sealing member is pushed out in a direction to fill the opening in response to the pressure applied by the holder in the direction of insertion of the plug assembly into the header assembly. Such a configuration enables the sealing member to plug and seal the opening. 
   In accordance with another embodiment of the present invention, the afore-mentioned connector assembly can further comprise a positioning device configured to ensure proper positioning of the holder in order to enable the sealing member to plug and seal the opening. 
   Due to afore-mentioned configuration of the positioning device, the holder can be positioned in a desired position. Accordingly, the sealing member is securely pushed out in response to the pressure applied by the holder, leaving no opening at all between the plug assembly and the header assembly. 
   In accordance with yet another embodiment of the present invention, during the afore-mentioned connector assembly, the plug assembly can comprise the plug assembly comprises a holder base positioned at an end of the holder, and one or more holders layered upon the holder base. 
   The connector assembly comprising a plug assembly which has the holder base and the one or more holders layered thereupon, enables the sealing member to plug and seal the opening which exists between the multi-layered holders and the header assembly, more efficiently. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded perspective view of a connector assembly according to an embodiment of the present invention; 
       FIG. 2A  is a side view illustrating a behavior of a sealing member according to an embodiment of the present invention prior to mating of the connector assemblies; 
       FIG. 2B  is a side view illustrating a behavior of a sealing member according to an embodiment of the present invention after mating of the connector assemblies; 
       FIG. 3  is a cross sectional view of the connector assembly of  FIG. 1 ; 
       FIG. 4  is an exploded perspective view of a rear holder of the connector assembly of  FIG. 1 ; 
       FIG. 5  is an exploded perspective view of a sealing member of the connector assembly of  FIG. 1 ; 
       FIG. 6  is a perspective view illustrating the manner in which the holders of the rear holder of  FIG. 4  and the sealing pieces of the sealing member of  FIG. 5  are assembled to one another; 
       FIG. 7  is a perspective view illustrating an assembly of the holder and the sealing piece of  FIG. 6 ; 
       FIG. 8  is a perspective view illustrating the manner in which the assembly of the holder and the sealing piece, as shown in  FIG. 6 , and a plate-like housing are assembled to each other; 
       FIG. 9  is a partially exploded perspective view of a plug assembly during the connector assembly of  FIG. 1 ; 
       FIG. 10  is a perspective view illustrating the manner in which plate-like housings of the plug assembly of  FIG. 9  are assembled to one another. 
   

   The foregoing summary, as well as the following detailed description of certain embodiments of the present invention, will be better understood when read in conjunction with the appended  FIGS. 1-10 . For the purpose of illustrating the invention, there is shown in the drawings, certain embodiments. It should be understood, however, that the present invention is by no means limited by the appended drawings. 
   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring to  FIGS. 1-4 , a connector assembly  1  comprises a connector housing  2 , at least one pair of holder assemblies  3 , and at least one sealing member  4 . The connector housing  2  comprises a header assembly  5 , an outer case  6 , at least one plug assembly  7  as a male block, and a positioning device  60  (i.e., a positioning area) as a positioning means. 
   The header assembly  5  is formed of electrically insulating materials such as synthetic resin, and formed into a tubular shape, comprising an oppositely facing wall  9  having a plurality of holes  8  through which the male tab of the male terminal of a mating connector to be mated with the connector assembly  1  are passed, and a plurality of side walls  10 , each of which extends from each edge of the oppositely facing wall  9  in a direction perpendicular to the wall  9 . Space inside the header assembly  5  is divided into several compartments, for example, three compartments in accordance with an embodiment of the present invention. 
   The outer case  6  is formed of electrically insulating materials such as synthetic resin and formed into a tubular shape. The outer case  6  is secured to the header assembly  5  while receiving the header assembly  5  and the plug assembly  7  therein. 
   In accordance with an embodiment of the present invention, there are provided three plug assemblies  7 . As viewed in  FIGS. 1 and 3 , the plug assembly  7  comprises a plurality of plate-like housings  11  and a cover  12 . The plug assembly  7  comprises four plate-like housings  11  in  FIGS. 1 and 3 . The plate-like housing  11  is formed of electrically insulating materials such synthetic resin, and formed into a plate shape. The plate-like housing  11  comprises a plurality of terminal receiving grooves  14  for receiving terminal fittings  13  (shown in  FIG. 3 ). A plurality of terminal receiving grooves  14  are formed with recesses on the exterior surface of the plate-like housing  11 , and are arranged in parallel to one another. The plate-like housings  11  are layered upon one another. 
   The cover  12  is formed of electrically insulating materials such as synthetic resin, and formed into a C-shape, including a flat top wall  15 , and side walls  16  extending from each edges of the top wall  15  in a direction perpendicular to the top wall  15 . The cover  12  is layered on top of the multi-layered plate-like housings  11  such that the top wall  15  plugs the terminal receiving groove  14  of the plate-like housing  11 , is also positioned in order to accommodate a plurality of plate-like housings  11  between a pair of side walls  16 , and is secured to the plate-like housings  11 . During the plug assembly  7 , the plate-like housings  11  configured to receive the terminal fitting  13  attached to the electrical wire  17  into the terminal receiving groove  14 , are layered upon one another, are covered with the cover  12 , and are secured to the cover  12 . 
   The rear holder  3  is formed of electrically insulating materials such as hard-type synthetic resin which does not resiliently deform. Each plug assembly  7  in accordance with an embodiment of the present invention includes a pair of holder assemblies  3 . As shown in  FIG. 4 , each of holder assemblies  3  comprises a holder assembly  18  (shown as a base holder  18   a,  top holder  18   b  and intermediate holders  18   c ), an engaging section  19 , and a guiding section  20 . The holder assemblies  3 , for example, may include five holders  18   a,    18   b  and  18   c.    
   In accordance with an embodiment of the present invention, a plurality of holders are layered upon one another, and are positioned at one end of the holder assembly  3 . As shown in  FIGS. 4 and 5 , the base holder  18   a  includes a pair of rails  21  which are arranged in parallel to each other, and a bar-shaped connecting section  22  configured to connect one ends of the rails  21  to each other, and is formed into a C-shape. Each of rails  21  is extending from the respective end of the connecting section  22  in a direction toward the intermediate holders  18   c,  and is formed into a bar-shape. The rails  21  are arranged in parallel to each other, while maintaining spaced-apart relationship. 
   The other four holders (top holder  18   b  and intermediate holders  18   c ) are formed into a bar-shape extending in their horizontal direction respectively. These four holders are arranged between a pair of rails  21 , being parallel to the connecting section  22 . The four holders  18   b  and  18   c  are arranged in parallel to one another, are spaced from one another, and are layered upon the holder base. 
   Referring to  FIG. 4 , the engaging section  19  comprises an engaging protuberance  23  located at the opposite end of the rail  21  (i.e. the end situated away from the connecting section  22 ), and a engaging recess  24  formed at both ends of the top holder  18   b  in the longitudinal direction, wherein the top holder  18   b  is placed farthest away from the connecting section  22  of the base holder  18   a.  In other words, a plurality of the engaging section  19  are located at the opposite ends of the rails  21  (i.e., the ends other than the ends adjacent to the connecting section  22 ) and both ends of the top holder  18   b.  The engaging protuberance  23  is blade-like protuberance extending from the opposite end of the rail  21  in a direction toward the oppositely facing rail  21 . The top holder  18   b  has the engaging recess  24  at its both ends in the longitudinal direction. When the engaging protuberance  23  is received in engaging recess  24 , the both ends of the top holder  18   b  and the opposite ends of the rails  21  are engaged respectively in the engaging section  19 . 
   The guiding section  20  comprises a guiding protuberance  25  located at both ends of the intermediate holders  18   c  other than base holder  18   a  and top holder  18   b  in its longitudinal direction, and a guiding groove  26  located at a pair of rails  21 . In other words, the guiding section  20  is formed extending from the intermediate holders  18   c  to the rail  21 . 
   The guiding protuberance  25  is formed projecting from both ends of the intermediate holders  18   c  in its longitudinal direction. The guiding groove  26  is recessed from the oppositely facing surfaces of a pair of rails  21 . The guiding groove  26  is disposed along the longitudinal direction of the rail  21 , and limited by the whole length of the rail  21 . By the presence of the guiding groove  26 , the cross section of the rail  21  represents a C-shape. Because the guiding protuberance  26  is received in the guiding groove  26 , the guiding section  20  supports the intermediate holders  18   c  such that the holders  18   c  may move freely along the guiding groove  26  (i.e., the longitudinal direction of the rail  21 ). 
   After the connecting section  22  of the base holder  18   a  and the intermediate holders  18   c  are arranged in parallel to one another, the intermediate holders  18   c  are press-fitted between a pair of rails  21 . At this point, the guiding protuberance  25  of the intermediate holders  18   c  is in turn inserted into the guiding groove  26  of the base holder  18   a.  Next, the intermediate holders  18   c  are press-fitted between a pair of rails  21 . When the guiding protuberance  25  of the intermediate holders  18   c  is received in the corresponding guiding groove  26 , the intermediate holders  18   c  can move freely along the longitudinal direction of the rail  21 . 
   Further, by press-fitting the top holder  18   b  between a pair of rails  21 , the engaging protuberance  23  can be received in the engaging recess  24 . After the connecting section  22  and the top holder  18   b  and intermediate holders  18   c  are arranged in parallel to one another while maintaining spaced-apart relationship, the rear holder  3  can be assembled thereto. Accordingly, such an assembled rear holder  3  not only can be attached to the plug assembly  7  together with the sealing member  4 , but also can be press-fitted into the outer case  6  together with the plug assembly  7 , and is finally coupled to the connector housing  2 . When the rear holder  3  is coupled to the connector housing  2 , the electrical wire  17  is positioned among the base, top and intermediate holders  18   a,    18   b  and  18   c.    
   The sealing member  4  is formed of resilient materials such as rubber. The sealing member  4  is, for example, provided within the plug assembly  7 . As shown in  FIG. 5 , the sealing member  4  includes a plurality of sealing pieces  27  (shown as base sealing piece  27   a,  top sealing piece  27   b  and intermediate sealing piece  27   c ). In accordance with an embodiment of the present invention, the sealing member  4  can include five sealing pieces  27 . 
   Each of sealing pieces  27  is formed into a bar-shape. The sealing pieces  27  are arranged in parallel to one another, having spaced-apart relationship. The base sealing piece  27   a  situated at the bottom among a plurality of sealing pieces (refer  FIG. 5 ) includes a plurality of grooves  28  formed on its surface opposed to the other sealing pieces  27   b  and  27   e.  Each of grooves  28  is recessed from the surface of the base sealing piece  27   a,  representing an arc-shape in cross section. A plurality of grooves  28  are arranged in a row along the longitudinal direction of the base sealing piece  27   a.  Each of grooves  28  extends along the width direction of the sealing piece  27   a.    
   A top sealing piece  27   b  situated at the highest point among a plurality of sealing pieces (refer  FIG. 5 ) includes a plurality of grooves  28  formed on its surface opposed to the other sealing pieces  27   a  and  27   c.  Each of the intermediate sealing pieces  27   c  includes a plurality of grooves  28  on its upper surface and under surface. In other words, each of the intermediate sealing pieces  27   c  includes a plurality of grooves  28  on its surface which is opposed to the sealing piece  27   a,    27   b  or  27   c.  The electrical wire can pass through the sealing pieces  27   a,    27   b  and  27   c  via the afore-mentioned grooves  28 . 
   By means of an adhesive and the like, two base holders  18   a  are attached to the base sealing piece  27   a,  two holders  18   b  are attached to the top sealing piece  27   b,  and two holders  18   c  are attached to each of remaining intermediate sealing pieces  27   c,  respectively. At this point, the base sealing piece  27   a  is positioned between two holders  18   a  along the longitudinal direction of the grooves  28 . Similar to the base sealing piece  27   a,  the sealing pieces  27   b  and  27   c  are also positioned between two holders  18   b  and between two holders  18   c,  respectively. In this way, the sealing pieces  27   a,    27   b  and  27   c  are attached to the respective holders  18   a,    18   b  and  18   c,  respectively. 
   In addition, when the intermediate holders  18   c  are layered upon the connecting section  22  of the base holder  18   a,  the intermediate sealing pieces  27   c  are in turn layered upon the base sealing piece  27   a.  Finally, when the top holder  18   b  is layered upon the intermediate holders  18   c,  the top sealing piece  27   b  is layered upon the intermediate sealing piece  27   c.  As the holder assembly  3  is assembled, simultaneously the sealing pieces  27   a,    27   b  and  27   c  are in turn layered, to provide the sealing member  4 . 
   At this point, as shown in  FIG. 9 , the electrical wire  17  attached to the terminal fitting  13  which is received within the terminal receiving groove  14  of the plate-like housing  11 , is positioned among the sealing pieces  27   a,    27   b  and  27   c.  Precisely, the electrical wire  17  is positioned inside afore-mentioned groove  28 . 
   The sealing pieces  27   a,    27   b  and  27   c  are clipped on the base holder  18   a.  The side  27   d  of the sealing piece  27   a,    27   b  or  27   c  represents, as shown in  FIG. 2A , an arc-shape in cross section in the direction of arrow X (i.e., insertion direction), and the corresponding circumferential plane and the holder  18   a  are substantially coplanar. In other words, even if the sealing member  4  comprising the sealing pieces  27   a,    27   b  and  27   c  is inserted into the header assembly  5 , it still comes into contact with the inner surface of the header assembly  5 , and therefore prevents the restitution force from occurring. 
   When the sealing pieces  27   a,    27   b  and  27   c  are inserted into the header assembly  5 , the holder  18   d  is pressed in a direction of X (i.e., insertion direction) and then the sealing pieces are sandwiched between the holders  18   d  and  18   e  of the plug assembly  7 . As a result, the sealing pieces  27   a,    27   b  and  27   c  are compressed, and, as viewed in  FIG. 2B , are pushed out from the surface of the base holder  18   a  in a direction toward the inside of the header assembly  5  to an extent of Au to form a protuberance portion  27   d,  which acts to plug and seal the opening  50  that exists between the header assembly  5  and the plug assembly  7  (refer  FIG. 3 ), thereby ensuring that moisture cannot pass into said opening. 
   The afore-mentioned positioning device  60  includes an engaging section  61  and an engaging recess  62 . The engaging section  61  is formed in a pair on both upper surface and under surface of the holder  18   d.  As shown in  FIG. 3 , the engaging recess  62  is formed corresponding to the shape of the engaging section  61  on the inner surface of the header assembly  5 . In cases where the sealing member  4  has a width of “Z”, as shown in  FIG. 2B , when the sealing member  4  is compressed by the holder  18   d  to an extent of ?u, the engaging recess  62  is positioned such that it may be engaged with the engaging section  61 . Because of afore-mentioned compression, the sealing member  4  are pushed out from the surface of the holder  18   a  in a direction toward the inside of the header assembly  5  to an extent of ?u, allowing the opening  50  to be securely plugged. In addition, the positioning area  60  may be designed depending on elasticity of the sealing member  4 . 
   Moreover, for example, the sealing member  4  can be embedded between the holder  18   f  and  18   e,  or between the holder  18   d  and the plug assembly  7  in the absence of holder  18   e.  The engaging recess  62  of the positioning device  60  may be formed in the outer case  6 , as the case may be. 
   The plug assembly  7  is assembled, and then the rear holder  3  and the sealing member  4  are attached to the plug assembly  7 , to provide the above mentioned connector assembly  1 . The terminal fitting  13  attached to the electrical wire  17  is press-fitted into the terminal receiving groove  14  of the plate-like housing  11 . Subsequently, the terminal fitting  13  attached to the electrical wire  17  is assembled to the plate-like housing  11 . 
   As shown in  FIGS. 6 and 7 , by means of an adhesive and the like, two base holders  18   a  are attached to the base sealing piece  27   a,  two top holders  18   b  are attached to the top sealing piece  27   b,  and two intermediate holders  18   c  are attached to the intermediate sealing piece  27   c,  respectively. Then, as shown in  FIG. 8 , the plate-like housing  11  is attached to the base sealing piece  27   a  and the base holder  18   a  in such a manner that the electrical wire  17  is put inside the groove  28  of the base sealing piece  27   a.  After the top sealing piece  27   b  is layered upon the electrical wire  17  inside the plate-like housing  11 , the electrical wire  17  of the other plate-like housing  11  is layered upon the afore-mentioned assembly. As a result, as shown in  FIG. 9 , the sealing pieces  27   a,    27   b  and  27   c,  and the plate-like housings  11  are alternately layered, thereby sandwiching the plate-like housing  11  between two sealing pieces. 
   Thereafter, a plurality of plate-like housings  11  are pressed such that the plate-like housings  11  may approach one another to form the assembly of the plate-like housings  11 . In addition, the base holders  18   a  and top holders  18   b  are fixed to each other by way of the engaging section  19  in order to assemble the base, top and intermediate holders  18   a,    18   b  and  18   c  as well as to assemble the sealing pieces  27   a,    27   b  and  27   c.  As shown in  FIG. 10 , the rear holder  3  and the sealing member  4  are attached to a plurality of plate-like housings  11  which have already been assembled to one another. Thereafter, the cover  12  is attached to the afore-mentioned assembly. In this way, the plug assembly  7  is assembled, and then the rear holders  3  and the sealing member  4  are also assembled to the plug assembly  7 . In addition, a ring-like perimeter seal  30  is positioned around the plug assembly  7 , thereby providing the connector assembly  1  with enhanced sealing performance according to the present invention. 
   After the plug assembly  7  is inserted into the header assembly  5 , the plug assembly  7 , the rear holder  3  and the sealing member  4  are press-fitted to the outer case  6  in the direction of “X” (i.e., insertion direction). As this occurs, the engaging section  61  of the positioning device  60  will be inserted into the engaging recess  62 . The sealing member  4  will be compressed and then pushed out from the surface of the holder  18   a  in a direction toward the inside of the header assembly  5 , forming the protuberance portion  27   d.  Such a protuberance portion  27   d  can plug and seal the opening  50  which has been formed between the header assembly  5  and the plug assembly  7 , thereby ensuring that moisture cannot pass into the opening therebetween within the connector assembly  1 . 
   The connector assembly  1  assembled as described above can be coupled to a mating connector. Such an assembly may be used with an automobile wiring harness system. 
   In accordance with the embodiment of the present invention, since the connector assembly  1  is designed to plug and seal the opening  50  which exists between the header assembly  5  and the plug assembly  7  by means of the sealing member  4 , which is pushed out in a direction toward the opening  50  as mentioned above, in cases where the plug assembly  7  is inserted into the header assembly  5 , the restitution phenomenon of the sealing member  4  will not occur, and said opening can be securely plugged. As a result, it is possible to provide a connector having enhanced sealing performance, as well as considerably decreased insertion force during the assembly process. 
   Moreover, because the holder assembly  18   d  is positioned such that the sealing member  4 , regardless of its restitution force, may plug and seal the opening  50  which exists between the plug assembly  7  and the header assembly  5 , improved sealing performance can be achieved between the plug assembly  7  and the header assembly  5 . 
   Further, even if the plug assembly  7  includes a plurality of plate-like housings  11  (i.e., the multi-layered holders), the opening between the plug assembly  7  and the header assembly  5  can be plugged securely. Therefore, it is possible to provide a connector having enhanced sealing performance, as well as considerably decreased insertion force during the assembly process. 
   In accordance with the embodiment of the present invention, the sealing pieces ( 27   a,    27   b  and  27   c ) which constitute the sealing member  4  are attached to the base holder, top holder and intermediate holders ( 18   a,    18   b  and  18   c ) which constitute the rear holder  3 , by means of an adhesive and the like. However, the sealing pieces  27   a,    27   b  and  27   c  may also be molded integrally with the base holder, top holder and intermediate holders  18   a,    18   b  and  18   c,  for example, by insert molding. 
   While a preferred embodiment of the invention has been shown and described with particularity, it will be appreciated that various changes and modifications may suggest themselves to one having ordinary skill in the art upon being apprised of the present invention. It is intended to encompass all such changes and modifications as fall within the scope and spirit of the appended claims.