Abstract:
An environmentally sealed electrical connector system for connector boxes used in the proximity of water includes an anchored connector which mounts into the face plate of the box from the rear, to facilitate making wiring connections in the box before installing the face plate. A mating plug-in connector forms an environmental seal around the connector contacts when mated with the anchored connector, and locking arms secure the plug-in connector to the face plate when mated. A two-piece construction allows the plug-in connector to have hard portions for locking, and soft portions for sealing.

Description:
FIELD OF THE INVENTION 
     This invention relates to environmentally sealed electrical connectors, and more particularly to improved connectors which facilitate installation of equipment boxes in spas, pools, washing machines and the like, and which are resistant to accidental disconnection. 
     BACKGROUND OF THE INVENTION 
     U.S. Pat. No. 5,401,181 to Wilson discloses an environmentally sealed electrical connector system in which mating female and male connectors are provided, respectively, with a bead and groove that cooperate, when the connectors are mated, to form a moisture-tight seal around the mating contacts. One of the uses of the connector system of U.S. Pat. No. 5,401,181 involves a connection box for spas, washers or the like, in which one of the connectors is anchored in the face plate of the box, and the other is used to plug an external cable into the anchored connector. For this purpose, the anchored connector takes the form shown in U.S. Pat. No. Des. 360,871 to Wilson. 
     In the Wilson system, the female connector of U.S. Pat. No. 5,401,181 is anchored in the face plate by threading the wires or cable attached to it from the front through precut openings in the face plate, and then pushing the connector into the opening until the wedge-shaped teeth shown in U.S. Pat. No. Des. 360,871 catch on the back side of the face plate and lock the anchored connector to the face plate. 
     It has been found in practice that although the system of U.S. Pat. No. 5,401,181 and U.S. Pat. No. Des. 360,871 performs adequately, it is not entirely satisfactory in two respects. First, because the anchored connector of U.S. Pat. No. Des. 360,871 must be inserted from the front of the face plate, the wires attached to it must be connected inside the box with the face plate present. This causes problems because work space inside the box is limited (particularly if more than one anchored connector is provided), and the handling and movement of the face plate and anchored connectors during connection work frequently causes paint scratches and dirt stains on the face plate. 
     Another problem with the prior art system is that the wires or cable attached to the plug-in (usually the male) connector are sometimes subjected, in tight places, to a bending stress that causes the male and female connectors to become misaligned, and thereby to jeopardize the moisture seal even if the connectors do not become completely disconnected. 
     SUMMARY OF THE INVENTION 
     The present invention overcomes the drawbacks of the prior art by providing a connector system in which an anchored connector can be inserted through a cutout in the face plate of a box, from the rear of the face plate, after the wiring connections have been made outside of the box. Furthermore, in accordance with the invention, the plug-in connector is equipped with one or more resilient hooked arms that lockingly engage the face place cutouts when the connectors are mated. The locking of the plug-in connector to the face plate prevents the plug-in connector from becoming misaligned or detached from the anchored connector. 
     In other aspects of the invention, the plug-in connector is formed of two different materials to provide both a firm lock to the face plate, and a soft exterior hood for an effective moisture seal. Also, provision is made for the ground contact to extend farther outward from the connectors than the hot contacts, so that the ground connection will be made first when the connectors are mated. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the connectors of this invention; 
     FIGS. 1 a  and  1   b  illustrate two versions of the environment in which the invention is useful; 
     FIGS. 2 a-c  are a side elevation, broken-away top view and front elevation, respectively, of the female connector; 
     FIGS. 3 a-c  are like views of the male connector; 
     FIGS. 4 a-c  illustrate sequential steps in the fabrication of the male connector; 
     FIGS. 5 a  and  5   b  illustrate the installation of prior art connectors in a connection box; 
     FIGS. 6 a  and  6   b  illustrate the installation of the inventive connectors in a connection box; and 
     FIG. 6 c  is a horizontal section along line  6   c — 6   c  of FIG. 6 b , but with the interior details of the connectors  10  and  12  omitted. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 shows the connectors  10 ,  12  of this invention. Although either of the connectors  10 ,  12  may be the male or female, it will be assumed in the following discussion that the plug-in connector  10  is the male, and that the anchored connector  12  is the female. The plug-in connector  10  includes, as discussed in more detail below, a pair of locking arms  14 , a contact block  16 , and a resilient hood  18  that sealingly surrounds the outer end of the anchored connector  12  when the connectors  10 ,  12  are mated. As shown in U.S. Pat. No. 5,401,181, one of the connectors  10 ,  12  includes an annular ridge  20  which cooperates with a matching groove  22  in the other connector to produce a moisture-proof seal around the contacts  24 ,  26  (the latter shown in FIGS. 2 b  and  2   c ) when the connectors  10 ,  12  are mated. 
     FIGS. 1 a  and  1   b  illustrate an environment in which the connector system of this invention is particularly useful. Moisture-proof connection boxes  28  are used in many environments and appliances where the presence of water presents a potential shock, corrosion and/or short circuit hazard. Typically, such boxes contain wiring interconnections, and they are closed off by a face plate  30 . The face plate  30  typically forms a seal with the box  28  to prevent moisture from entering the box  28 . The face plate  30  is also typically provided with cutouts  32  of standard dimensions. The cutouts  32  are usually rectangular in shape and have ears  34   a ,  34   b  that may be square (FIG. 1 a ) or rounded (FIG. 1 b ). 
     For use in the above-described environment, the anchored connector  12  has a body  36  (FIGS. 2 a-c ) of resilient polyvinyl chloride (PVC) material that is conventionally molded around the female contacts  26  after the wires  38  (FIG. 1) have been attached to them. At its outer or forward end, the anchored connector  12  carries a bead  20  which interacts with the groove  22  (FIG. 3 a-c ) of the plug-in connector  10  to form an annular moisture seal in the manner described in U.S. Pat. No. 5,401,181. Adjacent to its front end, the anchored connector  12  is equipped with wedge-shaped protrusions  44  which deform as the connector  12  is passed through the cutout  32  (FIGS. 1 a ,  1   b ) from the rear of the face plate  30 , and then snap back to prevent rearward movement of the connector  12 . In that condition, the connector  12  is anchored in the face plate  30  by the protrusions  44  and the wall  46  formed in the body  36 . 
     The plug-in connector  10  is fabricated, according to the invention, in a two-step process. The male contacts  24 , with the cable  46  attached (FIG. 4 a ) are placed in a jig (not shown), and a contact block  16  of nonconductive polystyrene is formed around them (FIG. 4 b ). The block  16  has a pair of arms  14  formed integrally with it. The arms  14  carry locking hooks  52  at their ends. Although the material of block  16  is quite hard, it has sufficient resiliency to allow the arms  14  to bend to a small degree. Thus, when the connectors  10 ,  12  are mated, the locking hooks  52  can pass through the ears  34   a  or  34   b  of the cutouts  32 , and then spring outwardly behind the face plate  30  to lock the connector  10  in place. Because it is desirable to fill the cutout  32  as much as possible, the arms  14  and hooks  52  preferably have a cross section corresponding to the square (FIG. 1 a ) or rounded (FIG. 1 b ) shape of the ears  34   a ,  34   b.    
     The fabrication of plug-in connector  10  continues by placing the block  16  into a mold (not shown), and forming around it a soft, resilient hood  18  of PVC, preferably the same material as the body of the anchored connector  12  (FIG. 4 c ), and softer than the material of hook  52 . The hood  18  is shaped to engage and surround the forward end of connector  12 , and to lie sealingly against the face plate  30  when the connectors  10 ,  12  are mated to the point where the annular groove  22  inside the hood  18  sealingly engages the bead  20  of the connector  12 . It is to be noted that the arms  14  are positioned laterally outwardly of the hood  18  so as to be flexible independently of the hood  18 . 
     FIGS. 5 a, b  and  6   a, b  illustrate the installation of a connector system in the face plate  30  of a connection box  28 . In the prior art (FIGS. 5 a, b ), the female connector  56  of the Wilson patents was inserted through the cutout  32  from the front of the face plate  30  prior to connection of its wires  58  (FIG. 5 a ). The connections inside the box  28  were then made with the face plate  30  present. The presence of the face plate  30  not only made connection work inside the box  28  more awkward, but it also sometimes resulted in damage to the finish of face plate  30 . When the male connector  60  of the prior Wilson patents&#39; system was plugged into the connector  56  (FIG. 5 b ), a downward stress on the cable  62  (as, for example, by other cables  63 ) easily resulted in the formation of a moisture-admitting gap  64 , or even a disconnection of the connectors  56 ,  60 . 
     By contrast, in the inventive system (FIGS. 6 a-c ), the connection of wires  38  inside the box  28  is done first, without the face plate  30  being present. When all the connections have been made, the anchored connectors  12  are inserted into the face plate  30  from the rear (FIG. 6 a ), and the face plate  30  is attached to the box  28 . The connectors  10   10  can now be plugged into the connectors  12 , and as the arms  14  engage the face plate  30  with their hooks  52  (FIG. 6 c ), the connectors  10 ,  12  cannot be separated or misaligned by a downward or sideways stress on the cable  46 . 
     One of the features of the present invention is that during the mating of the connectors  10 ,  12 , the ground connection is made before the connection of the hot contacts  24 ,  26 , and that during the disengagement of connectors  10 ,  12 , the ground connection is not broken until after the hot contacts  24 ,  26  have separated. For that purpose, at least one of the ground contacts  66 ,  68 , and preferably both, extends farther outwardly of its respective connector  10 ,  12  as best shown in FIGS. 3 b ,  4   c ,  2   a  and  2   b.    
     It is understood that the exemplary environmentally sealed connector system described herein and shown in the drawings represents only a presently preferred embodiment of the invention. Indeed, various modifications and additions may be made to such embodiment without departing from the spirit and scope of the invention. Thus, other modifications and additions may be obvious to those skilled in the art and may be implemented to adapt the present invention for use in a variety of different applications.