Abstract:
An electrical outlet box having a generally rectangular box having a back wall, a perimetrical side wall surrounding the back wall defining an open front face and a box interior, the side wall comprised of a first and second set of generally parallel spaced apart wall portions, outwardly directed flanges extending from one set of parallel wall portions adjacent the open front face; and fastening structures integrally formed with and attached to the flanges for rigidly mounting the electrical outlet box to a structural member.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit of U.S. Provisional Application No. 60/416,794 filed on Oct. 8, 2002. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates generally to an electrical outlet box for housing electrical fixtures such as a switch or a receptacle. More particularly, the present invention relates to an improved electrical outlet box for use on concrete wall.  
         BACKGROUND OF THE INVENTION  
         [0003]    It has long been known to house electrical fixtures such as switches and receptacles in an electrical outlet box. The outlet box permits the insertion of electrical wires into the box which are terminated to electrical fixtures. The fixtures then may be mounted to the box which provides protection to the fixtures as well as the wires terminated therein. The outlet box is then mounted to a wall at a convenient location to provide access. Most outlet boxes accommodate one or more electrical fixtures, which terminate standard 110 volt electrical wires.  
           [0004]    Outlet boxes are available in a variety of configurations and sizes. The selection of which type of box to use is dependant upon the specifics of the application. The most commonly employed box is a single-gang outlet box, also referred to as a standard outlet box. The single-gang box is ideal for applications in which only one receptacle is required for the application. Standard outlet boxes have opening dimensions of approximately 3″×2-¼″ and are available in a variety of depths. Double-gang and triple-gang boxes are also available, and they typically have the capacity to hold two and three receptacles respectively. A four inch (4″) square box is also commonly employed for multiple receptacle applications.  
           [0005]    Typically, outlet boxes are mounted by affixing mounting ears to a wall stud or other structural member. However for some applications, such as exterior uses, the outlet box, may be mounted within a concrete structure. This is accomplished by attaching the box to a form in the desired location. The form is unusually a wooden temporary structure used to contain the poured concrete in the desired shape that is removed after the concrete has hardened. The outlet box remains in the concrete after removal of the form.  
           [0006]    It is necessary when using an outlet box in such an application to insure that it is securely affixed to the form to resist being displaced during the concrete pour. Presently, outlet boxes are affixed to the form using nails or screws. Current design boxes usually provide holes on a flange for receiving a fastener such as a nail to affix the box to a form. Upon removal of the forms, the nails (or screws) remain in the concrete, and need to be cut away in order to avoid being in the way during further work such as the installation of drywall. This requires an extra step and can leave an undesirable sharp edge or projection where the fastener was cut.  
           [0007]    Therefore it would be desirable to have an outlet box for use in concrete walls, incorporating features which make cutting of the protruding nails or screws unnecessary.  
         SUMMARY OF THE INVENTION  
         [0008]    Applicant has overcome the shortcomings of prior art outlet box with the present invention by incorporating prongs that are adapted to being hammered into a concrete form, prior to pouring concrete. Once the forms are removed, the prongs can be hammered to a position that is parallel to the wall surface.  
           [0009]    The present invention further provides for holes that are adapted to releasably retain a fastener such that the it can be removed after the concrete has hardened.  
           [0010]    Therefore there is provided an electrical outlet box having a generally rectangular box having a back wall, a perimetrical side wall surrounding the back wall defining an open front face and a box interior, the side wall comprised of a first and second set of generally parallel spaced apart wall portions, outwardly directed flanges extending from one set of parallel wall portions adjacent the open front face; and fastening structures integrally formed with and attached to the flanges for rigidly mounting the electrical outlet box to a structural member. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    [0011]FIG. 1 a - 1   d  show in side view, a typical installation of the outlet box of the current invention.  
         [0012]    [0012]FIG. 2 is a perspective view of one embodiment of the front of the outlet box of the present invention.  
         [0013]    [0013]FIG. 3 is a perspective view of the front of an alternate embodiment of the present invention.  
         [0014]    [0014]FIG. 4 a - 4   e  show a perspective view of various alternate embodiments of the present invention.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0015]    There will be detailed below the preferred embodiments of the present invention with reference to the accompanying drawings. Like members are designated by like reference characters in all figures.  
         [0016]    Referring now to the drawings, there is shown in FIG. 1 a - 1   d , a typical installation of an outlet box  100  in a concrete wall application.  
         [0017]    [0017]FIG. 1 a  shows a front form  102  and rear form  104 , used to retain poured concrete to construct a vertical wall. As is well known, such forms may be constructed of wood stud, planks or sheets such as plywood. The side  106  of outlet box  100  is fastened to front form  102 . The outlet box  100  must be securely fastened to the form when the concrete  108  is poured. Typically, the outlet box  100  is nailed to the form by driving the fastener through apertures provided on exterior flanges, of outlet box into the form. It should be noted that a wire, not shown in this view, would typically be installed in the outlet box prior to the pouring of the concrete wall.  
         [0018]    [0018]FIG. 1 b  depicts the outlet box  100  positioned within the wall  116  after the concrete has been poured and hardened. Secure attachment of the box  100  to the form  106  maintains the box  100  in proper position during the concrete pour.  
         [0019]    After the concrete has hardened, the forms are removed, as shown in FIG. 1 c , thereby exposing the concrete wall front  110  and rear  112  surface. Removal of the forms also exposes the front of outlet box, as well as the fasteners  114  used to affix the outlet box to front form  102 . In a prior art outlet box, the removal of the forms would expose the shank and point of the nail, or the screw threads which would subsequently be cut away. In accordance with the present invention, as will be explained further with reference to the FIGS.  2 - 4 , the fasteners can be removed or flattened flush with the wall surface. FIG. 1 d  depicts the finished installation of outlet box  100  after removal of the fasteners, showing the concrete wall  116 , furring strips  118 , drywall  120  and outlet box coverplate  122 .  
         [0020]    Turning now to FIG. 2, there is shown an embodiment of the outlet box of the present invention. There is shown an outlet box  200  which is generally a rectangular member having a back wall  202 , a pair of spaced apart side walls  204  extending from back wall  202 , and opposed top and bottom walls  206  and  208 . Back wall  202 , side walls  204  and top and bottom walls  206  and  208  form a box interior  210  having an open front face  212  which accommodates therein an electrical fixture. Open front face  212  has a dimension substantially equivalent to the opening of a double-gang outlet box. The interior length and width of the opening will vary depending on if receptacle mounting flanges disposed on the box are interior or exterior to the box opening. However, the outlet box depicted here is illustrative and not intended to be limiting. It will be appreciated that it would be apparent to have an outlet box according to the present invention having alternate dimensions according to the application of such outlet box.  
         [0021]    As is well known in the art, outlet box  200  may include one or more access openings, typically known as knockouts  214  which permit entry of electrical wires and cables (not shown) into box interior  210 . The exterior surfaces of top  206  and bottom walls  208  include mounting flanges  216  and  218  respectively which allow the box to be secured to a concrete form or the like in conventional fashion by use of a fastener such as a nail or screw. The interior surfaces of side walls  204  include component retaining flanges  220  and  222  which include apertures  224  for receiving fasteners, usually screws, to securely mount electrical components within the outlet box and screws  226  for securely attaching a ground wire to the outlet box. Mounting flanges  216  and  218  are outwardly bent with respect to the top  206  and bottom  208  of the outlet box. Mounting flanges  216  and  218  include apertures  228  for affixing the outlet box to a concrete form in the conventional way, such as for example, by placing outlet box open face  212  against a concrete form and driving a nail (not shown) through the apertures  228  to securely mount the box to the concrete form.  
         [0022]    Alternately, the outlet box according to the present invention includes retracted prongs  230  on mounting flanges  216  and  218  for securely attaching outlet box to a concrete form. In this exemplary embodiment, the prongs are tabs, formed from the flange material, being pointed at one end and attached to the flange at the end opposite the pointed end. Each tab is folded back along its length to form a “v” such that the pointed end is positioned toward the outlet box opening and the apex of the “v” is extended toward the back wall  202 . In use outlet box open face  212  is placed against a concrete form and retracted prongs  230  are driven into the form, typically by hammering the apex of the prong to force the pointed end forward and into the form, thereby securely affixing the outlet box to the form. Upon removal of the forms, prongs  230  can be hammered flush with flanges  216  and  218 .  
         [0023]    Turning now to FIG. 3, an alternate embodiment of the present invention is shown. In the embodiment of FIG. 3, outside mounting flanges  216  and  218  extend from side walls  204 , inside component retaining flanges extend from top  206  and bottom  208  wall. In this embodiment flange  216  and  218  include slots  302  located at the uppermost side edge and bottom of flanges  216  and  218  respectively. Slots  302  permit the removal of a nail or screw, by providing a passage to slide out the nail head from behind the outlet box after the forms have been removed. In use, the open face  212  of outlet box  200  would be placed against a form and affixed by driving a nail into the form through slot  302 . After the concrete is poured and hardened the form is removed leaving the exposed fastener point and shank. The head of the fastener is retained behind the slot by the concrete. According to the present invention, the fastener can be removed by gripping the shank of the fastener, and forcibly moving it towards the open end of the slot until the fastener head is released.  
         [0024]    Alternately, the outlet box according to the present invention includes prongs  304  on mounting flanges  216  and  218  for securely attaching outlet box to a concrete form. In this exemplary embodiment, the prongs are tabs, formed from the flange material, being pointed at one end and attached to the flange at the end opposite the pointed end. Each tab protrudes orthogonally from the outlet box flange having the pointed end extending outwardly from flange  216  and  218 . In use, outlet box open face  212  is placed against a concrete form and flange  216  and  218  are hammered towards the form whereby prongs  304  are driven into the form. Upon removal of the form, prongs  304  can be hammered flush with the surface of flange  216  and  218 .  
         [0025]    Turning now to FIG. 4, another alternate embodiment of the present invention is shown. In the embodiment of FIG. 4, outside mounting flanges  216  and  218  include apertures  402  for releasably retaining fasteners used to affix the outlet box to a concrete form. Apertures  402  can comprise either deformable or removable structures as described below.  
         [0026]    More particularly, apertures  402  comprises a generally circular opening having an upper and lower tab  404 , each having a base  406  and a tip  408  extending towards the center of the opening. Tip  408  has a semicircular profile adapted to concentrically receive the shank of a fastener such as a nail. Tabs  404  can be a plastically deformable metallic material formed integrally with flanges  216  and  218 . The metallic material should be strong enough to securely affix outlet box  100  to a concrete form while allowing a fastener to be removed by pulling the head of the fastener through the aperture. After the fastener is removed, the deformed tabs can be hammered flush with the surface of flange  216  and  218 . Alternately, tabs  404  can removable structures wherein the base  406  is scored, i.e partially cut through, such that the tab will break away when subjected to the force of the fastener head being pulled through the aperture.  
         [0027]    It will be appreciated that aperture  402  can be formed of a variety of shapes and structures as shown in FIGS. 4 a - e , wherein various alternate embodiments are depicted.  
         [0028]    [0028]FIG. 4 a  depicts aperture  410  having a generally circular shape with three slots extending radially from the center of the aperture. In the preferred embodiment of aperture  410 , the radial slots define three deformable tabs  412  that are concentric with the central circular region. Tabs  412  can be alternately removable structures as previously described with respect to apertures  402 .  
         [0029]    It should be further noted that it would be apparent to modify aperture  410  to include any number of radial slots, for example, in FIG. 4 c , there is shown an aperture having two radial slots  414  extending from the generally circular center region.  
         [0030]    Similarly, FIG. 4 d , depicts an aperture having four radial slots  416  extending from the generally circular center region.  
         [0031]    A further alternate embodiment is depicted in FIG. 4 b , wherein there is shown a generally circular aperture  418 , having a slot  420  extending radially from the outer circumference of the circular opening wherein the slot has a width less than the diameter of the center circular region. The slot  420  is adapted to receive the shank of a fastener, such as a nail. The slot  420  however, is smaller than the diameter of a nail head typically used it this type of application. Whereas the generally circular aperture  418  has a larger diameter than the head of a nail typically used for this type of application.  
         [0032]    In use, the box according to the embodiment depicted in FIG. 4 b , is affixed to a form by driving a nail into a form through the aperture provided. After the concrete is poured and hardened the form is removed leaving the exposed fastener point and shank, with the head of the fastener retained behind slot  420 . According to the present invention, the user can remove the exposed fastener by gripping the fastener shank and moving the fastener towards the circular aperture  418  until the fastener head is released and thereby can be removed.  
         [0033]    A further alternate embodiment is depicted in FIG. 4 e , wherein there is shown an aperture  422  adapted to receive the shank of a nail or other such fastener, but having a diameter smaller than the head of a fastener typically used for this type of application. There is further provided a scored region  424  eccentrically surrounding aperture  422 , defining a break away tab  426  that facilitates the removal of a portion of the flange to permit the fastener head to be removed.  
         [0034]    In use, the box according to the embodiment depicted in FIG. 4 e , is affixed to a form by driving a nail into a form through the aperture provided. After the concrete is poured and hardened the form is removed leaving the exposed fastener point and shank. The head of the fastener is retained behind scored region  424 . According to the present invention, the user can remove the exposed fastener by gripping the fastener shank and pulling the fastener away from the wall, whereby the breakaway tab  426  is removed, and the fastener released.  
         [0035]    It will be appreciated that the present invention has been described herein with reference to certain preferred or exemplary embodiments. The preferred or exemplary embodiments described herein may be modified, changed, added to or deviated from without departing from the intent, spirit and scope of the present invention. It is intended that all such additions, modifications, amendments, and/or deviations be included within the scope of the claims appended hereto.