Panel mounted electrical connector with improved sealing system
FIELD OF THE INVENTION 
     This invention generally relates to the art of electrical connectors and, particularly, to a sealing system for sealing about an aperture in a panel which accommodates an electrical connector. 
     BACKGROUND OF THE INVENTION 
     There are a wide variety of electrical connectors which are mounted through an aperture in a panel and for coupling to a mating connector on a side of the panel opposite the direction of insertion of the connector. In some applications, it is desirable to close and seal the aperture in the panel to isolate the inner side of the panel from the outside environment, such as for moisture-proofing the arrangement. This often is accomplished simply by grommets which surround the connector and the edge of the aperture in the panel. The grommets may include body portions which surround and also provide protection for the connector itself, such as in the form of a boot. 
     Some panel mounted connectors also have latch means in the form of latch fingers for retaining the connector at a particular position relative to the aperture in the panel. Usually, the latch fingers on the connector engage the panel within the aperture therethrough. A sealing device, therefore, must accommodate these latch fingers and, consequently, a grommet extending through the aperture is impractical. In such applications, a sealing boot may surround the connector on the inside of the panel, with a peripheral sealing flange engaging the inside panel surface about the aperture in the panel and surrounding the connector and its latching fingers. The peripheral flange usually is flexible, and one of the problems in using such boots is to provide pressure which will maintain the flexible flange in sealing engagement with the panel surface. This may be accomplished by clamps, tape or the like, but such devices may become loosened and slippage occurs resulting in loss of the seal. 
     U.S. Pat. No. 5,044,986 to Baumanis, dated Sep. 3, 1991 and assigned the assignee of this invention shows a panel mounted, sealed electrical connector which is directed to solving these problems of providing an adequate seal by incorporating improved self-facilitating features in the sealing system. 
     On the other hand, attempts have been made to provide auxiliary pressure-backing means against the backside of the flexible peripheral flange of the sealing boot to maintain the flexible flange in sealing engagement with the panel surface. For instance, the connector housing may include rigid flanges which sandwich the peripheral flange of the sealing boot between the rigid flanges and the panel surface. However, such rigid backing flanges do not compensate for any irregularities in the panel surface and leakage may occur at particular points of irregularity about the periphery of the flexible flange of the boot. In fact, such rigid backing means may do more harm than good, versus a flexible peripheral flange, alone, which is allowed to flex about its entire periphery. 
     This invention is directed to solving the problems outlined above by providing further improvements in the sealing system of a panel mounted connector. 
     SUMMARY OF THE INVENTION 
     An object, therefore, of the invention is to provide a new and improved panel mounted, sealed electrical connector assembly for mounting in an aperture in a panel or the like. 
     In the exemplary embodiment of the invention, the connector assembly includes a connector housing having a front mating end adapted to be inserted through the aperture from a first surface to at least a second surface of the panel in order to mate with a complementary electrical component such as a complementary connector. Interengaging locking means are provided between the housing and the panel to mount the housing in the aperture. A sealing boot engages the housing rearwardly of the first surface and extends toward and engages the panel to surround and environmentally protect the aperture. 
     The invention contemplates the provision of resilient flange means surrounding a substantial portion of the periphery of the housing and which is adapted to be biased against the first surface of the panel. The sealing boot includes a flexible forward portion adapted to be received between the flange means of the housing and the first surface of the panel surrounding the aperture. Therefore, the flange means of the housing resiliently biases the flexible forward portion of the boot against the first surface of the panel to provide an environmental seal about the aperture in the panel. 
     As disclosed herein, the housing has a plurality of side walls, and the flange means are provided by a plurality of individual resilient flanges projecting outwardly from respective ones of the side walls. The flexible forward portion of the sealing boot is provided by a resilient lip surrounding the aperture and turned inwardly toward the housing between the first surface and the individual resilient flanges projecting outwardly from the housing side walls. The locking means are provided by a pair of locking members projecting from two side walls of the housing and extending through the resilient flanges of the housing for locking engagement with the panel at the periphery of the aperture. 
     Still further, the housing includes a rear end, and the sealing boot includes a rear portion surrounding the housing and adapted to rigidly embrace the rear end of the housing. 
     Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The features of this invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with its objects and the advantages thereof, may be best understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements in the figures and in which: 
     FIG. 1 is an exploded perspective view of a panel mounted, sealed electrical connector assembly embodying the concepts of the invention; 
     FIG. 2 is a vertical section through the panel and the sealing boot, illustrating the connector assembly mounted in an aperture in the panel; and 
     FIG. 3 is a horizontal section through the sealing boot as taken generally along line 3-3 of FIG. 2, but with a plan view of the connector housing to facilitate the illustration. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the drawings in greater detail, and first to FIG. 1, the invention is illustrated in a system which includes a sealing device or boot, generally designated 10, for closing an aperture 12 in a panel 14 which accommodates an electrical connector, generally designated 16. 
     Electrical connector assembly 16 includes a dielectric connector housing, generally designated 18, which is unitarily molded of insulating material such as plastic or the like. The housing is generally rectangular in configuration, as defined by first opposite side walls 20 and second opposite side walls 22. The housing has a front mating end 24 and a rear end 26, with a plurality of terminal-receiving through passages 28 therebetween. A plurality of terminals (not visible in the drawings) are mounted within the passages, with contact portions projecting outwardly through rear end 26. The housing is adapted to be inserted through panel aperture 12 in the direction of arrows &#34;A&#34; from a first or rear surface 32 to at least a second or front surface 34 of the panel in order to mate with a complementary electrical component or connector (not shown) which will have terminal means insertable into terminal-receiving cavities 28. In the illustrated embodiment of the invention, mating end 24 of housing 18 is inserted through aperture 12, past second surface 34 of the panel. 
     Electrical connector assembly 16 includes complementary interengaging locking means between housing 18 and panel 14 to mount the housing in aperture 12. Specifically, the locking means is provided by a pair of cantilevered locking arms 36 molded integrally with housing 18 and projecting outwardly and forwardly from side walls 20. Each locking arm includes a hook portion 36a for snapping against second or front surface 34 of panel 14 when the housing is inserted into aperture 12 in the direction of arrows &#34;A&#34;, as described in greater detail hereinafter. Housing 18 also includes a polarizing boss 38 projecting outwardly from one of the side walls 22, near mating end 24, for passing through a polarizing notch 40 at one edge of aperture 12. Boss 38 and notch 40 ensure proper orientation of the connector assembly within the aperture. 
     Still further, connector assembly 16, generally, includes resilient flange means surrounding a substantial portion of the periphery of housing 18 and which are adapted to bias a resilient lip (described hereinafter) of sealing boot 10 against rear surface 32 of the panel. More particularly, the resilient flange means are provided by four individual, elongated, resilient flanges 42 projecting outwardly from side walls 20 and 22 of the housing. The resilient flanges are unitarily molded with housing 18 by integral web portions or feet 44 with openings 45 therebetween. Therefore, the resilient flanges are flexible relative to the housing generally in the direction of doubleheaded arrow &#34;B&#34;, i.e. generally parallel to housing side walls 20 and 22 and perpendicular to rear surface 32 of panel 14. It should be noted that the one locking arm 36 visible in FIG. 1 clearly shows how the locking arm projects through the adjacent resilient flange 42 toward panel 14. Therefore, the locking arms can latch behind front surface 34 of panel 14 and resilient flanges 42 can be biased against rear surface 32 of the panel. 
     Sealing boot 10 is generally rectangular in configuration, complementary to rectangular connector assembly 16, and includes a forward portion 50 and a rear portion 52. As will be more clear with the description of FIG. 2, hereinafter, rear portion 52 rigidly embraces rear end 26 of connector housing 18, and the rear portion includes a plurality of slots or openings 54 for passage therethrough of the terminals projecting from the rear of the connector housing. Forward portion 50 is generally rectangular and is adapted for surrounding resilient flanges 42 which project outwardly from the housing. Lastly, again as described in greater detail hereinafter, forward portion 50 includes an inwardly directed, continuous, resilient sealing lip 56 which will be sandwiched between resilient flanges 42 of connector assembly 16 and rear surface 32 of panel 14 when connector assembly 16 is assembled to the panel, with mating end 24 of the housing projecting through aperture 12 and latch arms 36 locking the connector assembly mounted to the housing in the aperture. 
     Now, referring to FIGS. 2 and 3, it can be seen particularly in FIG. 2 that the mating end 24 of connector housing 18 has been inserted through aperture 12 in panel 14, past front surface 34 of the panel. The connector assembly is inserted in the direction of arrow &#34;A&#34;. When fully inserted, it can be seen that locking arms 36 project through aperture 12, and hook portions 36a are snapped behind front surface 34 of the panel to lock the connector assembly in its mounted position within the panel aperture. It also can be seen in FIG. 2 how the latch arms extend through openings 45 in resilient flanges 42 which project outwardly from housing 18. 
     Before housing 18 is inserted through panel aperture 12 as illustrated in FIG. 2, sealing boot 10 is assembled about the housing such that rear portion 52 of the boot rigidly embraces rear end 26 of the housing and forward portion 50 surrounds resilient flanges 42 of the housing. Peripheral resilient lip 56 is turned inwardly toward housing 18 and is sandwiched between rear surface 32 of panel 14 and resilient flanges 42 projecting outwardly of the housing. Therefore, the resilient flanges bias the lip portion against the rear surface of the panel and provide an environmental seal completely about aperture 12. Because of the resiliency of flanges 42, the flanges facilitate resilient lip 56 being effective to accommodate any irregularities in rear surface 32 of the panel. 
     It will be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.