Patent Document

BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The invention relates to click-fit connectors for securely mounting armored cables to a cable connector box. 
         [0003]    2. Related Prior Art 
         [0004]    A connector for armored cables including, but not limited to BX and MC cables, is configured to be removably mounted to a wiring box. Typically used in a space-deficient environment associated with electrical wiring, wiring boxes may not be easily or conveniently accessed. The wiring box has typically a housing provided with a bottom, a peripheral wall extending from the bottom, and a lid removably topping the peripheral wall and closing the interior of the box. The peripheral wall typically has a plurality of openings shaped and dimensioned to receive respective cable connectors. Typically, a cable connector is configured with a hollow body traversed by a cable which is secured to the connector by screws or other types of fasteners. The connector itself is, in turn, coupled to a wiring box by means of external fasteners. Hence mounting a cable connector traversed by an armored cable is usually an onerous and labor-intensive task. 
         [0005]    To minimize the above-discussed disadvantages associated with installation of armored cables, a click-fit connector has become available. The click-fit connector type is characterized by a hollow body configured with an inner spring which is operative to securely bias the installed connector against a wiring box and retain a cable within the connector. However, in practice, the engagement between a connector and box is not reliable, and the installed cable often wobbles and slips out of engagement. Furthermore, the known configuration of the click-fit connector does not provide reliable grounding of the installed cable. 
         [0006]    A need, therefore, exists for a click-fit connector for armored cables that has a configuration allowing for a reliable mounting thereof to an electrical box in a simple and time-effective manner. 
         [0007]    A further need exists for a click-fit connector for armored cables that has a configuration providing reliable grounding of an armored cable which is inserted into the connector. 
       SUMMARY OF THE INVENTION 
       [0008]    These needs are satisfied by the click-fit connection of the present disclosure. 
         [0009]    In accordance with one aspect of the present disclosure, a click-fir connector is configured with a hollow body, and first and second resilient components coupled to the hollow body and operative to bias the hollow body against a wall of a wiring box in opposite directions. Upon pulling the disclosed click-fit connector through an opening, which is formed in a wall of wiring box, the first and second resilient components press against the opposite sides of the wall and prevent the installed connector from voluntary displacement relative to the box. 
         [0010]    The first resilient component is configured as an elongated flexible body extending through the hollow interior of the connector&#39;s body between its rear and front ends. A lug provided on the front end of the first component is configured to extend transversely to the longitudinal axis of and through the front end of the hollow body and terminate at a radial distance from the hollow body of the connector. The lug has a generally V-shaped cross-section including a leaf which is biased axially rearwards from the front end of the flexible body. In the installed state of the connector, the leaf is in contact with and presses against the inner side of the box&#39;s peripheral wall which delimits the interior of the box. 
         [0011]    Advantageously, the first resilient component is configured to provide a multiplicity of contacts between the front lug or lugs and the inner side of the peripheral wall. Accordingly, due to multiple contacts between the installed connector and the inner side of the box&#39;s wall, the connector is centered about the axis of symmetry of an opening in the wall of the box, through which the connector is pulled in. 
         [0012]    The second resilient element includes at least one, but preferably multiple radially spaced prongs biased towards and pressing against the outer side of the wall of the box. In the installed state of the connector, the lugs and prongs engage the opposite sides of the wall of the box and minimize displacement of the installed connector relative thereto. 
         [0013]    In accordance with a further aspect of the disclosure, the first resilient element is provided with a pair of wings resiliently pressing against a cable upon inserting the latter into the body of the connector. The configuration of the wings helps improve engagement between the cable and connector and allows only rotational motion of these components relative to one another. The resiliency of the wings is essential to maintaining contact between the armored jacket of the inserted cable and connector which is necessary for reliable grounding of the cable. 
         [0014]    The above and other needs, objects, features, and advantages of the present invention will become apparent from the following description read in conduction with the accompanying drawings, in which like reference numerals designate the like elements. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1A  is a perspective view of a click-fit connector configured in accordance with the present disclosure. 
           [0016]      FIG. 1B  is a perspective view of the click fit connector of  FIG. 1A  provided with an anti-short isolator. 
           [0017]      FIG. 1C  is another perspective view of the click-fit connector of  FIG. 1A . 
           [0018]      FIG. 2  is a front elevational view of the click-fit connector of  FIGS. 1A and 1B . 
           [0019]      FIG. 3  is a side elevational view of the click-fit connector of  FIGS. 1A and 1B . 
           [0020]      FIG. 4  is a front elevational view of the click-fit connector of  FIG. 1B . 
           [0021]      FIG. 5  is a cross-sectional side view of the click-fit connector taken along lines A-A of  FIG. 4 . 
           [0022]      FIG. 6  is a perspective view of a first resilient component mountable to the interior of the click-fit connector of  FIGS. 1-5  and operative to stabilize the connector in its installed state relative to a wiring box and to provide reliable grounding of a cable received in the in the connector. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0023]    Reference will now be made in detail to several embodiments of the invention that are illustrated in the accompanying drawings. Wherever possible, same or similar reference numerals are used in the drawings and the description to refer to the same or like parts or steps. The drawings are in simplified form and are not to precise scale. For purposes of convenience and clarity only, directional terms, such as top, bottom, up, down, over, above, and below may be used with respect to the drawings. These and similar directional terms should not be construed to limit the scope of the invention in any manner. The words “connect,” “couple,” and similar terms with their inflectional morphemes do not necessarily denote direct and immediate connections, but also include connections through mediate elements or devices. 
         [0024]    Referring now to  FIGS. 1A ,  1 C and  3 , a connector  10  is configured with a hollow body  12  traversed by an armored cable, such as XK-290 or BX which has a helical armored jacket, which is not shown but well known to those skilled in the wiring electrical art. The body  12  is, then, mounted to a wall  50  (diagrammatically shown in  FIG. 3 ) of wiring box with the inner end of the inserted cable protruding into the interior of the box. 
         [0025]    As shown in  FIGS. 1A through 1C , body  12  includes a bushing  16  and a shaft  14  ( FIG. 1B ), respectively, with the front end of bushing  16  terminating within the interior of the box in the installed state of connector  10 . The bushing  16  and shaft  14  may be manufactured as two separate components assembled together to define preferably, but not necessarily, substantially cylindrical body  12 . Alternatively, bushing  16  and shaft  14  may be manufactured as a unitary component. The bushing  16  is configured with a collar  20  ( FIG. 1B ) provided between the front and rear portions of the busing and extending radially outwards from the periphery of hollow body  12 . In the installed state of connector  10 , collar  20  is juxtaposed with the outer side of wall  50  ( FIG. 3 ) of a wiring box and configured so as to prevent uncontrollable displacement of connector  10  through wall  50  into the interior of the box. The front end of bushing  16  may be chamfered to facilitate insertion of the bushing through the opening of wall  50  of the box. 
         [0026]    The shaft  14  is configured with a flange  46  ( FIG. 1A ) surrounding the rear end of bushing  16  and, thus extending radially outwards from the peripheral of bushing  16 . Accordingly, the sides of respective collar  20  and flange  46 , which face one another, define an annular channel  48  ( FIG. 1A ) therebetween which is configured to receive a washer  22  operative to bias connector  10  away from wall  50  of the box, as discussed in detail below. 
         [0027]    The collar  20  is machined with a plurality of notches  26  ( FIG. 1A ) spaced angularly from one another around the outer periphery of collar  20  at, preferably, a uniform distance and shaped to receive respective prongs or fingers  28  of washer  22  which extend from the outer peripheral edge of washer  22  and are, cumulatively, referred to as a resilient component. The prongs or fingers  28  each are angled with a free end thereof extending beyond the front face of collar  20  and resiliently urging against the outer side of wall  50  ( FIG. 3 ) of the box in the installed state of connector  10 . As a result, body  12  of connector  10  is biased rearwards from the wall  50  in the installed state of connector  10 . The inner radial side of washer  22  has a plurality of arms  24  ( FIG. 1A ) spaced from one another at preferably a uniform distance and located so that each pair of adjacent arms  24  flank a respective one of prongs or fingers  28  in between them. The arms  24  each extend along the longitudinal axis of elongated body  12  in a rearward direction and have its free portion pressing against flange  46  and, thus, generating a frontward-directed force compensating for the force generated by prongs or fingers  28  in the installed state of connector  10 . With the configuration disclosed immediately above, washer  22  has generally a Z-shaped cross-section allowing prongs or fingers  28  to be in continuous contact with wall  50  of the wiring box in the installed state of the connector. 
         [0028]    While prongs  28  have been disclosed on washer  22 , alternatively, collar  20  may have spaced-apart prongs functionally analogous to prongs or fingers  28 , but formed integrally with the outer peripheral side of collar  20 . Such a configuration of connector  10 , although not illustrated but readily understood by one of ordinary skill, has fewer components than the embodiment of  FIGS. 1A-1C , since the connector does not need to be assembled with a separate washer. 
         [0029]    Turning to  FIGS. 1B ,  4  and  5 , connector  10  further has an anti-short bushing  18  press-fit into bushing  16 . The assembly of bushings  18  and  16  is configured to prevent chaffing of the electrical wires of the inserted cable. 
         [0030]    Referring to  FIGS. 1B ,  3  and  6 , connector  10  further has a flexible spring  30  ( FIG. 6 ) removably mounted to the interior of body  12 . The spring  30  is operative to bias body  12  of connector  10  frontward from wall  50  of the box in the installed state of connector  10 . Configured with a flexible elongated body  34  ( FIG. 6 ), spring  30  has a front lug  32  which extends transversely to elongated body  34  through an opening in bushing  16  ( FIG. 1B ) and terminates at a radial distance from body  12  of connector  10 . 
         [0031]    Referring further to  FIGS. 5 and 3 , front lug  32  is formed by bending the front end of body  34  so that it assumes a substantially triangularly shaped cross-section having a first side  31 , which extends transversely to body  34 , and two sides  33  and  35  ( FIG. 5 ). The sides  33  and  35  extend angularly relative to one another with the free end of side  35  terminating in a close proximity to side  31 . Such a configuration allows front lug  32  to abut the inner face of wall  50  ( FIG. 3 ) by side  31  in the installed state of connector  10  and press thereagainst so as to bias connector  10  frontward from wall  50  and, thus, opposite to the rearward direction in which the connector is biased by prongs or fingers  28  of washer  22 . As a result, connector  10  is substantially displaceably fixed relative to wall  50  of the box. Furthermore, since both resilient components—prongs  28  and front lug  32 —are flexible, connector  10  can be displaceably fixed to wall  50  of the box practically regardless of the thickness of the wall, which is important because the wall thickness is not standardized. 
         [0032]    Returning to  FIGS. 6 and 1B , spring  30  further has an intermediary pair of lugs  36  and a rear pair of lugs  38  ( FIG. 6 ) configured to extend through respective holes in body  12  of connector  10 , as shown in  FIG. 1B . Once lugs  36  and  38 , respectively, protrude beyond body  12 , their respective free ends are bent to conform to the outer periphery of body  12 , thus, displaceably fixing spring  30  to body  12 . 
         [0033]    As also shown in  FIG. 6 , spring  30  further has a pair wings  40  provided on body  34  between intermediate and rear pairs of lugs  36  and  38 , respectively, and extending in a direction opposite to the direction of extension of these lugs. In other words, wings  40  extend inwards and are in contact with a helical jacket of cable when the latter is pulled through the hollow body  12  of connector  10 . Due to the flexibility of spring  30 , wings  40  resiliently press against the cable&#39;s jacket as the cable and assembled connector  10  rotate relative to one another during insertion of the cable into connector  10 . The free ends  44  of wings  40  are slanted to conform to the helical thread of the cable&#39;s jacket, and the length of one of the wings is greater than the length of the other wing. The continuous contact of wings  40  with the jacket of the cable also improves grounding characteristics of connector  10 . 
         [0034]    Preferably, two or more springs  30  are mounted to the diametrically opposite regions of the interior of connector  10  to have front lugs  32  of respective springs  30  provide multiple, spaced-apart contact points between connector  10  and wall  50  of the wiring box which improve stability and positioning of connector  10  relative to the wiring box. However, as readily understood by an artisan, single spring  30  can be provided with two front lugs  32  coupled to the front end of spring  30  and extending in opposite direction relative to one another. 
         [0035]    During an initial installation of connector  10 , body  12  is first tilted so that one of front lugs  32  of respective springs  30  is pulled through an opening in wall  50  of wiring box and engages the inner side of wall  50 . Thereafter, upon pushing connector  10  frontward, the other front lug  32  is depressed upon contact with the periphery of the opening allowing connector to snap in place so that the opposite sides of wall  50  are pressed upon by respective front lugs  32  and prongs  28  of washer  22 . In the installed state of connector  10 , its axial displacement is, thus, arrested, but its rotation relative to wiring box is possible upon applying a torque to body  12 . 
         [0036]    Subsequently, an armored cable or flexible conduit connector is pushed inside body  12  of connector  10  while, along a way, deflecting wings  40 . Due to the configuration of wings  40 , the cable can only advance frontward, but its linear displacement in a rearward direction is arrested by wings  40  pressing against the helical thread of the cable. With the cable inserted through hollow body  12 , the armored jacket of the cable presses against front lugs  32  preventing these lugs from displacing radially inwards, which, otherwise, would result in disengagement of connector  10  from the wiring box. 
         [0037]    In case of a wiring mistake or a need for retrofitting mounted connector  10 , body  12  of connector  10  rotates, for example, in a clockwise direction allowing the cable to rotate in the opposite direction out of engagement with connector  10 . Alternatively, of course, the cable may be rotated in a counterclockwise direction until it is out of engagement with connector  10 . 
         [0038]    Having described at least one of the preferred embodiments of the present invention, which was conceived in 2005 and reduced to practice in 2006, with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes, modifications, and adaptations may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims.

Technology Category: 4