Patent Publication Number: US-2017373479-A1

Title: Electrical Connector

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of the filing date under 35 U.S.C. §119(a)-(d) of Japanese Patent Application No. 2016-125745, filed on Jun. 24, 2016. 
     FIELD OF THE INVENTION 
     The present invention relates to an electrical connector and, more particularly, to a partially waterproof electrical connector. 
     BACKGROUND 
     In known electrical connectors used in applications in which the connector is exposed to water, the water generally falls onto an upper part of the connector in the vertical direction. The water received in the upper part spreads in a gap between a case enclosing the connector and the connector, enters the case, and reaches a side of the case. In this side, the water spreads in a gap between the case and the connector and may reach an innermost part of the case which must be protected against water for proper electrical function. 
     In known electrical connectors, a rubber seal ring that is separate from a housing is positioned to prevent water from entering the electrical connector. In addition to the seal ring, some known housings have an inclined surface so as to discharge water that has entered the connector. Japanese Patent Application No. 2011-150895A, for example, discloses an inclined surface formed at an inner surface of a case enclosing a connector so that water that has entered a gap between the case and the connector flows toward an opening. JP 2011-150895A discloses that a groove is formed toward the opening in the inclined surface and the capillary action due to the groove enhances the drainage performance. The inclined surface disclosed in JP 2011-150895A is provided between the case and the connector so as to discharge the water entering the connector, however, the inclined surface cannot prevent the water from entering the connector. The structure disclosed in JP 2011-150895A includes a seal ring, which allows water to enter until the water reaches the area of the seal ring. 
     The seal ring, although affording waterproof protection to the connector, is nonetheless an additional member required in the assembly of the connector. Accordingly, if the electrical connector is used in an application in which water penetration is unlikely, there is no need to provide a seal ring and it is sufficient to ensure a partial or light waterproof performance. 
     SUMMARY 
     An electrical connector according to the invention comprises a housing and a contact held by the housing. The housing has a hood including a receiving space for receiving a mating connector and a pair of first inner surfaces extending along a vertical direction. The first inner surfaces face the receiving space and are disposed at a first interval in a horizontal direction. Each of the first inner surfaces includes a first inclined surface extending a predetermined distance from a front end of the hood in a mating direction toward an opposite rear end of the hood. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will now be described by way of example with reference to the accompanying Figures, of which: 
         FIG. 1  is a perspective view of an electrical connector assembly according to the invention; 
         FIG. 2  is another perspective view of the electrical connector assembly of  FIG. 1 ; 
         FIG. 3  is a sectional plan view of the electrical connector assembly taken along line III-III of  FIG. 1 ; 
         FIG. 4A  is a side view of the electrical connector assembly of  FIG. 1 ; 
         FIG. 4B  is a sectional side view of the electrical connector assembly taken along line IIb-IVb- of  FIG. 1 ; 
         FIG. 5A  is a sectional plan view of a portion of the electrical connector of  FIG. 1 ; 
         FIG. 5B  is a sectional perspective view of a portion of the electrical connector of  FIG. 1 ; 
         FIG. 6A  is a detail plan sectional view of a first housing of the electrical connector assembly of  FIG. 1 ; 
         FIG. 6B  is a detail side sectional view of the first housing; 
         FIG. 7A  is schematic front view of the first housing; 
         FIG. 7B  is another schematic front view of the first housing; and 
         FIG. 8  is a sectional view of an electrical connector according to another embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENT(S) 
     Embodiments of the present invention will be described hereinafter in detail with reference to the attached drawings, wherein like reference numerals refer to the like elements. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein; rather, these embodiments are provided so that the disclosure will be thorough and complete and will fully convey the concept of the invention to those skilled in the art. 
     An electrical connector assembly according to the invention is shown in  FIGS. 1-3 . The electrical connector assembly includes an electrical connector  10  and a mating connector  30 . The mating connector  30  is matable with the electrical connector  10 . In the shown embodiment, the electrical connector  10  is a receptacle connector that is configured to be fixed to, for example, a printed wiring board (not shown) and the mating connector  30  is a plug connector. In the shown embodiment, the electrical connector  10  has a structure in which three mating connectors  30  are aligned and mated with the electrical connector  10 ; only one mating connector  30  is shown in  FIGS. 1-3 . 
     A side at which the electrical connector  10  and the mating connector  30  are mated together is defined as a front side of each connector  10 ,  30 , and a side opposite to the front side is defined as a rear side. A side of the electrical connector assembly that is fixed to the printed wiring board and faces the printed wiring board is defined as a lower side, and a side of the electrical connector assembly that is opposite to the lower side is defined as an upper side. The major components of the invention will now be described in greater detail. 
     The electrical connector  10 , as shown in  FIGS. 1-3 , includes a first housing  11  and a plurality of first contacts  29 . The first housing  11  is integrally formed of an electrically insulative resin. The first contacts  29  are formed of a material having high conductivity, such as a copper-based material. 
     The first housing  11 , as shown in  FIG. 3 , has a holding wall  12  holding the first contacts  29 ; the first contacts  29  are disposed at intervals. On one surface of the holding wall  12 , a hood  13  configured to be mated to the mating connector  30  is formed. The hood  13  has a rectangular tubular shape defining an insertion opening  18  opposite the holding wall  12 . The hood  13  includes a plurality of receiving spaces  19  for receiving the mating connectors  30 . In the shown embodiment, the hood  13  is partitioned into three hoods  13  by partition walls  17 , and the mating connectors  30  are mated with the receiving spaces  19  respectively corresponding to the three hoods  13 . 
     As shown in  FIGS. 1-3 , one part of each of the first contacts  29  that is configured to be electrically connected to a contact of the mating connector  30  extends into the corresponding receiving space  19  and another part of each of the first contacts  29  that is configured to be connected to the printed wiring board (not shown) extends rearward from the holding wall  12 . The part of each of the first contacts  29  extending rearward, as shown in  FIGS. 2 and 3 , is bent by 90 degrees in the middle of the first contact  29 . The first contacts  29  are arranged in a plurality of rows in a width direction x and are also arranged in a plurality of columns in a height direction z. 
     The hood  13  includes an upper wall  14 , a lower wall  15 , and a pair of side walls  16  as shown in  FIGS. 1-3 . The upper wall  14  and the lower wall  15  extend in the width direction x and are opposed to each other at a predetermined distance. The pair of side walls  16  connects both ends of each of the upper wall  14  and the lower wall  15  in the height direction z. In the hood  13 , the above-mentioned partition walls  17  connect the upper wall  14  and the lower wall  15  to each other in the height direction z at positions where the hood  13  is partitioned into three hoods  13  in the width direction x. The side walls  16  and the partition walls  17  are disposed at predetermined intervals in the width direction x. A first lock projection  17 , as shown in  FIG. 4B , is formed on an inner surface of the hood  13 . 
     The hood  13 , as shown in  FIGS. 1-3 , has a first inclined surface T 1  disposed at a front end of an inner surface  21  of each of the side wall  16  and the partition wall  17  facing the receiving space  19 . The first inclined surface T 1  is inclined from the front end toward a rear end of the hood  13  such that the thickness of each of the side wall  16  and the partition wall  17  continuously increases along the first inclined surface T 1 . The first inclined surface T 1  extends a predetermined distance from the front end of the hood  13  toward the rear end thereof. The first inclined surface T 1  is disposed along an entire length of the inner surface  21  in the height direction z or vertical direction. 
     As shown in  FIGS. 1, 2, and 4B , the hood  13  also has second inclined surfaces T 2 , T 3 . The second inclined surfaces T 2 , T 3  are formed at a front end of an inner surface  23  of each of the upper wall  14  and the lower wall  15  facing the receiving space  19 . The second inclined surfaces T 2 , T 3  are inclined from the front end to the rear end of the hood  13  so that the thickness of each of the upper wall  14  and the lower wall  15  continuously increases along the second inclined surfaces T 2 , T 3 . The second inclined surfaces T 2 , T 3  extend the predetermined distance from the front end of the hood  13  toward the rear end thereof. Further, the second inclined surfaces T 2 , T 3  are disposed along an entire length of the inner surface  23  in the width direction x so that ends of each first inclined surface T 1  are connected to an end of the second inclined surfaces T 2 , T 3 . 
     The mating connector  30  is shown in  FIGS. 1-4B . The mating connector  30  includes a second housing  31  and a plurality of second contacts (not shown) held by the second housing  31 . The second housing  31  holds a number of second contacts corresponding to the number of first contacts  29 , which are held by the electrical connector  10 , at positions corresponding to those of the first contacts  29 . The materials of the second housing  31  and the second contacts are the same as those of the first housing  11  and first contacts  29  of the first connector  10 . 
     The second housing  31 , as shown in  FIGS. 1-3 , includes a housing body  33  that holds the second contacts. A rear end wall  35  of the second housing  31  is continuous with a rear end of the housing body  33 . A plurality of contact receiving holes  34  is formed along one direction of the housing body  33 . The second contacts (not shown) are inserted into the respective contact receiving holes  34 . The contact receiving holes  34  penetrate the rear end wall  35 . 
     A lock arm  40  is disposed at a central part in the width direction on an upper surface of the housing body  33  as shown in  FIGS. 1-3 . The lock arm  40  is formed integrally with the housing body  33 . A front end side of the lock arm  40  forms a support end  41  that is fixed to the housing body  33  and a rear end side of the lock arm  40  forms an operation end  42 . The lock arm  40  includes a second lock projection  43  formed between the support end  41  and the operation end  42 . The second lock projection  43  and the first lock projection  27  are locked to each other as shown in  FIG. 4B , thereby preventing the mating connector  30  from being removed from the electrical connector  10 , when the electrical connector  10  and the mating connector  30  are mated together. 
     A drainage operation of the electrical connector  10  will now be described with reference to  FIGS. 5A-7B . 
     The drainage operation of the first inclined surface T 1  is shown in  FIGS. 5A-6B . When the electrical connector  10  and the mating connector  30  are mated together, as shown in  FIGS. 5A and 5B , a gap having a triangular prism shape is formed due to the presence of the first inclined surface T 1 . As described below, this gap functions as a drainage path R. 
     A quantity of water W, shown in  FIGS. 6A and 6B , falls onto the insertion opening  18  of the electrical connector  10  from above. As shown in  FIG. 6B , the water W enters the gap between the inner surface  23  of the upper wall  14  of the first housing  11  and the outer surface  37  of the second housing  31  from the insertion opening  18 . Since the gap between the inner surface  23  and the outer surface  37  is narrow, the water W advances in the gap between the inner surface  23  and the outer surface  37  in the width direction x and a mating direction y as shown in  FIG. 6A . 
     The water W which has advanced in the width direction x reaches both ends where the first inclined surfaces T 1  are disposed; the water W which has reached the first inclined surfaces T 1 , as shown in  FIG. 6B , is classified broadly into water W that advances in the mating direction y toward the back of the side wall  16  and water W that advances in the vertical direction z toward the lower side of the side wall  16 . However, since the first inclined surface T 1  is provided on the side wall  16 , a larger quantity of water W flows downward in the vertical direction along the first inclined surface T 1  due to gravity rather than flowing toward the back of the side wall  16 . Since the first inclined surface T 1  reaches the inner surface  23  of the upper wall  14 , the water W which has reached the both ends of the outer surface  37  in the width direction x largely flows toward the first inclined surface T 1  rather than flowing toward the back of the side wall  16 . While the side wall  16  has been described, the same holds true of the partition wall  17  provided with the first inclined surface T 1 . Further, since the first inclined surface T 1  reaches the inner surface  23  of the lower wall  15 , as shown in  FIG. 6B , the water W that falls down along the inclined surface T 1  may be discharged from the insertion opening  18  to the outside of the first housing  11 . 
     In the electrical connector  10 , the first inclined surface T 1  is provided on each of the side wall  16  and the partition wall  17  along the vertical direction which allows the water W which has entered the insertion opening  18  between the first housing  11  and the second housing  31  to be largely guided toward the lower side in the vertical direction and discharged to the outside of the first housing  11 , suppressing the flow of the water W toward the back of the hood  13 . 
     As shown in  FIG. 7A , in the electrical connector  10 , the upper wall  14  is also provided with the second inclined surface T 2 . Accordingly, on the upper wall  14 , the water W flows toward both ends of the second inclined surface T 2  in the width direction x, rather than flowing to the back, and reaches the first inclined surface T 1  formed on the side wall  16  or the partition wall  17 . The drainage path R formed by the second inclined surface T 2  functions as a guide for carrying the water W toward the drainage path R formed by the first inclined surface T 1 . 
     As shown in  FIG. 7B , in the electrical connector  10 , the lower wall  15  is also provided with the second inclined surface T 3 . Accordingly, when the water W flowing to the lower end along the first inclined surface T 1  reaches the second inclined surface T 3  at both ends thereof in the width direction x, the water W may flow along the drainage path R formed by the second inclined surface T 3  toward the center in the width direction x. Since the second inclined surface T 3  is inclined downward from the back toward the front side, when the water W flows in accordance with the inclination of the second inclined surface T 3 , the water W is discharged from the insertion opening  18  to the outside of the first housing  11 . 
     In another embodiment shown in  FIG. 8 , a passageway  25  is disposed extending through the lower wall  15  adjacent to a projection  28  which is located at an end of the second inclined surface T 3  of the lower wall  15 . The passageway  25  is disposed at the back of the hood  13  relative to the second inclined surface T 3 , and the water W in contact with the projection  28  that does not flow along the second inclined surface T 3  flows through the passageway  25  and is discharged to the outside of the first housing  11 . 
     In the above embodiments, the first inclined surface T 1  is disposed along the entire height direction z and the second inclined surfaces T 2 , T 3  are disposed along the entire width direction x. In other embodiments, the first inclined surface T 1  may be disposed along only a portion of the height direction z and the second inclined surfaces T 2 , T 3  may be disposed along only a portion of the width direction x. However, in these embodiments, the first inclined surface T 1  extends along a length that is equal to or more than half the length in the height direction z and the second inclined surfaces T 2 , T 3  extend along a width that is equal to or more than half the width in the width direction x. 
     Angles formed by the inclined surfaces T 1 , T 2 , and T 3  may be determined to obtain the desired effect described above. The angles may be in a range from 5° to 25° or may be in a range from 10° to 20°. The length of each of the inclined surfaces T 1 , T 2 , and T 3  from the front end of the hood  13  toward the back thereof may determine to obtain the desired effect. The length may be in a range from 3 mm to 10 mm or may be in a range from 5 to 8 mm.