Patent Publication Number: US-6910905-B2

Title: Waterproof connector

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a waterproof connector. 
   2. Description of the Related Art 
   A waterproof connector wherein the chamber containing the terminals is sealed is described in Japanese Patent Application No. 2001-267000. This waterproof connector is described below with reference to FIG.  11 . The waterproof connector has a female housing  1  provided with a plurality of the cavities  1 A for accommodating female terminals  2 . The male housing  3  is designed for a printed-circuit board and includes a hood part  3 A in which the female housing  1  can be fitted. L-type male terminals  4  project from the front end surface  3 B into the hood part  3 A. A mounting concavity  5  is formed around the projected portion of the male terminal  4  on the front end surface  3 B of the male housing  3 . A sealing member  6  is mounted in the mounting concavity  5 . 
   A press-fit groove  7  is formed around the opening  6 A on the surface of the sealing member  6 . On the front end surface  1 B of the female housing  1 , an annular rib  8  to be fitted in the press-fit groove  7  stands erect around the front opening of the cavity  1 A. 
   When the female housing  1  is connected to the male housing  3 , the rib  8  of the female housing  1  is pressed into the press-fit groove  7  of the sealing member  6 . Waterproofing of the chamber in female housing  1  can be accomplished by close contact between the peripheral surface of the rib  8  and that of the press-fit groove  7 . Waterproofing of the chamber in the male housing  3  can be accomplished by close contact between the peripheral surface of the mounting concavity  5  and that of the opening  6 A of the sealing member  6 . 
   However, in the above-described construction, the sealing member  6  is mounted on the male housing  3 . In mounting the sealing member  6  on the male housing  3 , it is necessary to insert the sealing member  6  into the hood part  3 A into which the male terminals  4  project and fit the sealing member  6  in the mounting concavity  5 . Thus, a connector with this conventional construction has a problem in that it takes much time and labor to perform the operation of mounting the sealing member  6  on the male housing  3 . 
   SUMMARY OF THE INVENTION 
   The present invention has been made in view of the above-described situation. Thus, objects of the present invention are to enable an easy mounting of a sealing member on a female housing and provide a compact connector. 
   To achieve the objects, there is preferably provided a waterproof connector comprising a female housing having a plurality of cavities accommodating a plurality of female terminals, and a male housing to be connected to the female housing and having a plurality of male terminals. The male terminals project from a front end surface of the male housing to connect to the female terminals. In this construction, a sealing member, having through-holes formed at positions to correspond to the cavities, contacts a front end surface of the female housing. Each of the through-holes is capable of contacting a peripheral surface of a projected portion of a corresponding male terminal at the front end surface of the male housing. 
   Preferably, the sealing member is held on the front end surface of the female housing by a holder mounted on the front end surface. 
   Preferably, the sealing member is formed integrally with the holder by two-color molding. 
   According to the present invention, the through-hole of the sealing member is closely fitted over the projected portion of the male terminal c when the female housing is fitted to the male housing. The sealing member is sandwiched between the front end surface of the female housing and that of the male housing. In the male housing, the inner peripheral surface of the through-hole of the sealing member closely contacts the peripheral surface of the sealing projection of the male terminal. In the female housing, the contact surface of the sealing member closely contacts (i.e., face contact) the front end surface of the female housing. In this way, waterproofing of the connector is accomplished. 
   Since the sealing member is installed on the exposed front end surface of the female housing, it is easy to install the sealing member into the connector. 
   In the sealing construction of the female housing, the sealing member makes face contact with the front end surface of the female housing. Thus, unlike the conventional case in which the inner peripheral surface of the sealing member contacts the peripheral surface of the terminal, it is unnecessary to provide the sealing member separately for each terminal or provide a space between adjacent terminals to insert a rib therebetween. Accordingly, it is possible to make the interval between the adjacent terminals short and to make the connector compact. 
   If there is a difference between the interval between the male terminals and that between the female terminals, the sealing member is capable of absorbing the difference. The sealing member slides on the front end surface of the female housing. In the male housing, the sealing member accomplishes uniform sealing by the circumferential close contact between the through-hole thereof and the sealing projection of the male terminal. In the female housing, the sealing member accomplishes uniform sealing by the close face contact between the contact surface thereof and the front end surface of the female housing. 
   By mounting the holder on the front end surface of the female housing, the sealing member is held on the front end surface with the sealing member in contact with the front end surface. 
   The sealing member is preferably formed integrally with the holder by two-color molding. In this way, the number of component parts can be reduced and the mounting operation can be performed easily. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side sectional view showing a state before a male housing and a female housing of a connector are fitted together according to an embodiment of the present invention. 
       FIG. 2  is a front view showing the male housing. 
       FIG. 3  is a side sectional view showing a state before a holder is mounted on the female housing. 
       FIG. 4  is a plan view showing the state before the holder is mounted on the female housing. 
       FIG. 5  is a front view showing a female housing. 
       FIG. 6  is a front view showing a holder. 
       FIG. 7  is a plan view showing a state in which the male housing and the female housing have been fitted together. 
       FIG. 8  is a side sectional view showing the state in which the male housing and the female housing have been fitted together. 
       FIG. 9  is a side sectional view of a concept drawing showing a state before the male housing and the female housing have been fitted together to indicate the concept of the embodiment. 
       FIG. 10A  is a side sectional view of a concept drawing showing a state in which the male housing and the female housing are fitted together. 
       FIG. 10B  is an enlarged sectional view taken along a line  10 B— 10 B of FIG.  10 A. 
       FIG. 11  is a side sectional view showing a conventional connector of the prior art. 
       FIG. 12  is a side sectional view of a concept drawing showing a state before the male housing and the female housing are fitted together to indicate the concept of the conventional connector of the prior art. 
       FIG. 13A  is a side sectional view of a concept drawing showing a state in which the male housing and the female housing of the prior art have been fitted together. 
       FIG. 13B  is an enlarged sectional view taken along a line  13 B— 13 B of FIG.  13 A. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   An embodiment of the present invention is described below with reference to  FIGS. 1 through 10 . 
   As shown in  FIG. 1 , the waterproof connector of the illustrated embodiment has a male housing  10 , a female housing  20 , and a sealing member  50  to be mounted on the female housing  20 . In the description below, the sides of the male housing  10  and of the female housing  20  that connect to the opposing housing are each considered as the front or forward side. 
   The male housing  10  is preferably of a substrate-installed type and made of a synthetic resinous material. A hood part  12  projects from a front surface of a body plate  11 . A mounting plate  13  for a printed-circuit board P is formed at a lower portion of a rear surface of the body plate  11 . The front surface of the body plate  11  serves as a front end surface  15  of the male housing  10 . 
   L-shaped male terminals  16  are mounted inside the male housing  10  by insert molding. As shown in  FIG. 2 , the male terminals  16  are preferably arranged in seven rows and three stages, with one end of each of them projecting into the hood part  12  from the front end surface  15 . A columnar sealing projection  17  extends from the front end surface about a projected portion of each of the male terminals  16 . 
   The other end of each of the male terminals  16  projects rearward from the rear surface of the body plate  11  and is bent downward. The mounting plate  13  is mounted on the printed-circuit board P. The other end of each of the male terminals  16  is soldered to a conductive path of the printed-circuit board P. A locking projection or member  19  is formed on an upper surface of the hood part  12  at a position near its front end. 
   The female housing  20  is also preferably made of a synthetic resinous material. The front side of the female housing  20  is block-shaped so that the front side thereof can be fit into the hood part  12  of the male housing  10 . The front surface of the female housing  20  serves as a front end surface  21 . 
   As also shown in  FIG. 5 , cavities  22  are formed inside the female housing  20  in a front-to-back direction thereof at positions corresponding to those of the male terminals  16  of the male housing  10 . As also shown in  FIG. 3 , a terminal insertion opening  23  is formed on the front end of each cavity  22  to receive one of the male terminals  16  therethrough for insertion into the female housing. A lance  24  is provided on the bottom wall of each cavity  22 . The lances can elastically deform in a space  25  disposed below the lances  24 . The front side of space  25  is open to form an insertion opening  26  into which an unlocking jig can be inserted. 
   As shown in  FIG. 3 , a mounting opening  28  open at the entrance of each cavity  22  is formed at the rear side of the female housing  20 . A one-piece rubber plug  29  is fit into the mounting opening  28  and held by a rubber plug-holding member  30 . 
   Female terminals  32  fixed to terminals of electric wires W penetrate through the one-piece rubber plug  29  and are inserted into the cavities  22  respectively from the rear thereof. As shown in FIG.  3 , when the female terminals  32  are inserted into the cavities  22  at a normal position, the lances  24  elastically bead and lock them into place to prevent removal of the female terminals  32 . Through-holes  29 A of the one-piece rubber plug  29  contact and closely hold the peripheral surfaces of each of the electric wires W. Accordingly, the entrance of each cavity  22  is closed. 
   A seesaw-shaped locking arm  34  that can be locked to the locking projection  19  of the male housing  10  is provided on the upper surface of the female housing  20 . 
   The chamber sealing member  50  is mounted on the front end surface  21  of the female housing  20 . 
   As shown in  FIGS. 3 and 5 , low ribs  35  are formed on the front end surface  21  of the female housing  20 , in the shape of a lattice in such a way that the ribs  35  surround the terminal insertion openings  23  and the jig insertion openings  26  of the cavities  22  respectively. 
   As shown in  FIG. 1 , a holder  40  is mounted on the front end surface  21  of the female housing  20 . Similarly to the female housing  20 , the holder  40  is preferably made of a hard resin such as PBT (polybutylene terephthalate). The holder  40  is cap-shaped to cover the front end portion of the female housing  20 . 
   As shown in  FIG. 6 , circular window holes  42  are formed on a front plate  41  of the holder  40 , at positions corresponding to those of the cavities  22 . The sealing projections  17  projecting forward from the front end surface  15  of the male housing  10  can be inserted into the window holes  42  respectively. The edge of each window hole  42  at its front surface side is tapered to guide the sealing projections  17  as they are inserted into their respective window holes  42 . 
   As shown in  FIGS. 3 and 6 , an elastically deformable, rearwardly extending cantilevered locking piece  44  is formed on each of the upper, lower, right, and left surfaces of the holder  40 . The locking piece  44  formed on the upper surface of the holder  40  is longer than the other three locking pieces  44  in the rearward direction. Complementing locking structures or projections  37  for elastically locking the locking pieces  44  thereto are formed on each of the upper, lower, right, and left surfaces of the female housing  20 . 
   As shown in  FIGS. 3 and 6 , a mounting concavity  46  is formed almost entirely across a rear surface of the front plate  41  of the holder  40 . A thick plate-shaped sealing member  50  is mounted inside the mounting concavity  46 . The sealing member  50  is preferably made of a hard resin (rubber) such as silicone rubber and formed integrally with the holder  40  by two-color molding. A rib  43  erect on the rear surface of the front plate  41  projects into the sealing member  50  to form a strong connection between the front plate  41  and the sealing member  50 . 
   Through-holes  51  are formed on the sealing member  50  at positions corresponding to those of the window holes  42  of the holder  40 . One lip  52  is formed on the inner peripheral surface of each through-hole  51 . The inner diameter of the lip  52  is a little smaller than the outside dimension of the sealing projection  17  of the front end surface  15  of the male housing  10 . 
   As shown in  FIG. 3 , the lip  52  at an upper stage is shifted rearward from the lip  52  at a lower stage. 
   The operation of the embodiment will be described below. 
   As shown in  FIG. 3 , after the female terminals  32  are inserted into all the cavities  22  and locked by the lances  24 , the holder  40  is put on the front end portion of the female housing  20  in the direction of arrow B. The holder  40  is pressed rearward, with the locking pieces  44  being elastically deformed outward by the respective locking projections  37 . When the holder  40  is pressed to a position where a contact surface  54  of the sealing member  50  is pressed against the front end surface  21  of the female housing  20 , as shown in  FIG. 1 , the locking pieces  44  elastically return to their original state so as to be locked to the corresponding locking projections  37 . In this way, the holder  40  is mounted on the female housing  20 . The sealing member  50  is elastically pressed against the front end surface  21  with the ribs  35  cutting into the contact surface  54 . 
   When the holder  40  and the sealing member  50  have been mounted on the female housing  20 , the female housing  20  is fit into the hood part  12  of the male housing  10  in the direction of arrow A (FIG.  1 ). As the coupling operation proceeds, the locking arm  34  elastically deforms and rides over the locking projection  19 . The front end of each male terminal  16  penetrates into its corresponding cavity  22  from the terminal insertion opening  23  through the window hole  42  of the holder  40  and the through-hole  51  of the sealing member  50  to connect to a connection portion  33  of the female terminal  32  accommodated in the cavity  22 . At the same time, the sealing projection  17  penetrates into the through-hole  51  of the sealing member  50  through the window hole  42  of the holder  40 , with the sealing projection  17  breaking the lip  52  formed on the through-hole  51  so as to be placed in sealing contact. 
   When the front plate  41  of the holder  40  is pressed to a normal position where the front plate  41  reaches the front end surface  15  of the male housing  10 , as shown in  FIG. 8 , the locking arm  34  elastically returns to its original state and is locked to the locking projection  19 . In this way, the male housing  10  and the female housing  20  are locked to each other in a normal connected state. At this time, the male terminals  16  and their corresponding female terminals  32  are connected to each other normally. Further, the front side of the sealing projections  17  are fit into the through-holes  51  of the sealing member  50  over the whole lengths. 
   In the male housing  10 , the inner peripheral surfaces of the through-holes  51  of the sealing member  50  closely contact the peripheral surfaces of the sealing projections  17 , with the sealing projections  17  breaking (i.e., folding) the lips  52 . In the female housing  20 , the contact surface  54  of the sealing member  50  is pressed against the front end surface  21  of the female housing  20 , with the rib  35  of the front end surface  21  cutting into the contact surface  54 . In this way, waterproofing in the chamber of the housing is accomplished. 
   By using concept views, the effect of the embodiment is described below in comparison with the conventional connectors of the prior art. The concept of the above-described embodiment of the invention is shown in  FIGS. 9 and 10 . The concept of the conventional art is shown in  FIGS. 12 and 13 . 
   The construction of the embodiment and that of the conventional art are briefly described from a conceptual standpoint below. In a conventional construction, the annular portion  6 B of the sealing member  6  is fit onto the projected portion  3 C of the male terminal  4  on the front end surface  3 B of male housing  3 . As a result, the male housing  3  is sealed from water. On the front end surface  1 B of the female housing  1 , the rib  8  is erect around the front opening of the cavity  1 A and fit onto the peripheral surface of the annular portion  6 B of the sealing member  6 . In this way, the female housing  1  is sealed from water. 
   On the other hand, in the embodiment of the present invention, the through-hole  51  of the sealing member  50  is fit onto the projected portion (sealing projection  17 ) of the male terminal at the front end surface  15  so that the male housing  10  is sealed to prohibit the ingresswater. The contact surface  54  of the sealing member  50  contacts (face contact) the front end surface  21  (rib  35 ) of the female housing  20 . Accordingly, the female housing  20  is sealed to protect the see page of water into the housing. 
   In the conventional sealing construction of the female housing, the inner peripheral surface of the sealing member  6  (particularly, annular portion  6 B) closely contacts the peripheral surface of the projected portion  3 C of the male terminal  4 . Thus, as shown in  FIG. 13B , it is necessary to provide a sealing member  6  separately for each projected position of the male terminal  4 , and to provide a space S between the adjacent male terminals  4  for the insertion of the rib  8  therebetween. 
   On the other hand, in the sealing construction of the female housing of the preferred embodiment of the invention, the sealing member  50  makes face contact with the front end surface of the female housing. Thus, as shown in  FIG. 10B , it is unnecessary to form the rib insertion space. As a result, it is possible to make the interval between the adjacent terminal fittings  16  short, and to make the connector compact. 
   For example, let it be supposed that the intervals between the male terminals and between the female terminals are different from each other. In the conventional construction, the rib  8  fits on the peripheral surface of the annular portion  6 B of the sealing member  6 , and thus prevents radial movement of the sealing member  6 . Therefore, in this example, referring to  FIG. 13B , the annular portion  6 B is compressed to a high degree along one side (shown with reference numeral  6 R) thereof, whereas the annular portion  6 B is compressed to a low degree along the other side (shown with reference numeral  6 L) thereof. Therefore the female housing  1  and the male housing  3  are non-uniformly sealed from water. 
   On the other hand, in the preferred embodiment of the invention, the sealing member  50  contacts (i.e., with face contact) the front end surface  21  of the female housing  20 . Thus, if there is a difference in the intervals between the male terminals and between the female terminals, the sealing member  50  is capable of absorbing the difference, with the sealing member  50  sliding on the front end surface  21  of the female housing  20 . That is, in the male housing  10 , the sealing member  50  accomplishes uniform sealing by the circumferential close contact between the through-hole  51  thereof and the sealing projection  17  of the male terminal  16 . In the female housing  20 , the sealing member  50  accomplishes uniform sealing by the close face contact between the contact surface thereof and the front end surface of the female housing  20 . 
   Further, since the sealing member  50  is installed on the exposed front end surface of the female housing  20  in the preferred embodiment, it is easy to perform the sealing member-installing operation. 
   Furthermore the sealing member  50  is held securely by the holder  40  and formed integrally with the holder  40  by two-color molding. Therefore the number of component parts can be reduced and the mounting operation can be performed easily. 
   The present invention is not limited to the embodiment described with reference to the drawings, but the following embodiments are included in the technical scope of the present invention. The present invention can be embodied by making various modifications if they do not depart from the gist of the present invention. 
   (1) In the above-described embodiment, the sealing member is formed integrally with the holder. However, the sealing member may be formed separately from the holder. 
   (2) In the case where the sealing member is formed separately from the holder, the sealing member may be directly held on the front end surface of the female housing without using the holder. 
   (3) The male housing may have cavities into which male terminals are inserted.