Patent Publication Number: US-6220897-B1

Title: Electrical outlet assembly

Description:
FIELD OF THE INVENTION 
     The present invention relates to an electrical outlet assembly for use in connecting an electrical appliance to a source of electrical power. 
     BACKGROUND TO THE INVENTION 
     Electrical outlets are common in residential and commercial establishments, and elsewhere, for connecting various electrical appliances to a source of electrical power. Commonly, electrical power is supplied to building through a central panel in which there are replaceable fuses or resettable breakers for each electrical circuit in the building. Each electrical circuit has one or more electrical outlets placed strategically in various rooms in the building. Most commonly, the electrical outlets are inset into walls. The outlets have a pair of sockets into which plugs of electrical appliances may be inserted. These electrical outlets are housed in metal boxes placed in the walls during construction where electrical power is needed. 
     As electrical appliances have become used more extensively, it has become common practice to use a device comprising a plurality of sockets connected electrically to a plug which is insertable into a wall socket. In this way, a plurality of appliances may be connected to a single wall socket. A special type of this device is a power spike and line noise protector which is useful for plugging in sensitive electronic equipment, such as computers. An example of a commercially available power spike and line noise protector is sold under the trade-mark, Power Bar. Power Bars typically have three to six sockets connected electrically to a plug at the end of an extension cord. Problems with Power Bars are that they can be tripping hazards and unsightly. A problem with conventional wall mounted electrical outlets is that, when there is a power overload and a breaker needs to be reset or a fuse needs to be replaced, one must go to the fuse box which is often inconveniently located in the basement or garage of a home. Also, many people are unfamiliar with the operation of central switch boxes and are hesitant or reluctant to attempt to reset a tripped breaker or to replace a burnt-out fuse. The present invention seeks to provide a solution to the aforementioned problems. 
     SUMMARY OF THE INVENTION 
     The present invention provides an electrical outlet assembly installable in a wall of a building for use in connecting an electrical appliance to a source of electrical power. The electrical outlet assembly includes an electrical outlet and a housing for releasably receiving the electrical outlet. The electrical outlet has at least one outlet socket for receiving an electrical connector of the appliance, an outlet connector, and means for electrically connecting the outlet socket to the outlet connector. The housing has a power terminal, the power terminal having a housing socket for releasably receiving the outlet connector, and means for electrically connecting the housing socket to a power source. The housing also has an opening sized to receive the electrical outlet therethrough and for communicating with an exterior of the wall when the housing is mounted inset in the wall. When the housing is mounted inset in the wall and the housing socket is connected to the power source, the electrical outlet may be releasably received in the housing by inserting the electrical outlet through the opening and releasably inserting the outlet connector in the housing socket. An electrical appliance may then be connected to the power source by inserting an electrical connector of the appliance in a socket of the electrical outlet. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Preferred embodiments of the invention will now be described with reference to the drawings in which 
     FIG. 1 is an isometric view of a wall-mountable electrical outlet assembly according to a first preferred embodiment of the invention, shown in an upright position; 
     FIG. 2 is an isometric view of a housing of the outlet assembly shown on its own in an upright position; 
     FIG. 3 is an isometric view of an electrical outlet of the outlet assembly shown on its own and placed horizontally; 
     FIG. 4 is another isometric view of the electrical outlet assembly shown with an optional face plate removably attached thereto; 
     FIG. 5 is a sectional view taken generally along line  5 — 5  of FIG. 4 with the housing removed for simplicity; 
     FIG. 6 is an isometric view of the electrical outlet assembly with an optional alternative face plate removably attached thereto; 
     FIG. 7 is a view similar to the view of FIG. 1 of a housing according to a second preferred embodiment of the invention shown in an upright position; and 
     FIG. 8 is a bottom view of a housing according to a third preferred embodiment of the invention. 
    
    
     Throughout the specification, directional indicators such as “top” and “bottom” are used in reference to the drawings and for convenience only. Furthermore, in this specification, the terms “comprising” and “comprises” are taken to specify the presence of the stated features, integers, steps or components but do not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. 
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring mainly to FIG. 1 but with reference also to FIGS. 2 and 3, an electrical outlet assembly designated generally by reference numeral  20  is shown. The outlet assembly  20  is installable in a cavity of a wall (not shown) of a building and is for use in connecting an electrical appliance (not shown) to a source of electrical power (also not shown). The outlet assembly  20  includes an electrical outlet  22  and a housing  24  for releasably receiving the electrical outlet  22 , as will be described further below. The electrical outlet  22  has four outlet sockets  28  for receiving an electrical connector in the form of a plug (not shown) of the appliance. Referring to FIG. 3, the electrical outlet  22  also has an outlet connector in the form of plug  30 , and means  32  (shown schematically in chain dotted outline in FIG. 3) for connecting the outlet sockets  28  to the plug  30 . Referring to FIG. 2, the housing  24  has a power terminal  34  which includes a housing socket indicated generally by reference numeral  36  for releasably receiving the plug  30  of the electrical outlet  22 . The power terminal  34  further includes means for connecting the housing socket  36  to the power source, as will be described further below. The housing  24  further has a front opening  40  sized to receive the electrical outlet  22  therethrough and for communicating with an exterior of the wall when the housing  24  is mounted inset in the wall. When the housing  24  is mounted inset in the wall and the housing socket  36  is connected to the power source, the electrical outlet  22  may be releasably received in the housing  24  (as shown in FIG. 1) by inserting the electrical outlet  22  through the opening  40  and inserting the plug  30  in the housing socket  36 . An electrical appliance may be then connected to the power source by inserting an electrical plug of the appliance in a socket  28  of the electrical outlet  24 . 
     As can be seen with reference to FIG. 2, the housing  24  is in the form of an open-fronted box having a back wall  42 , a pair of opposed side walls  44 , 46  extending forwardly from the back wall  40 , and a pair of opposed end walls  48 ,  50  extending between the side walls  44 ,  46  and forwardly of the back wall  42 . The housing socket  36  is disposed in the bottom end wall  50  which forms a top wall of a closed terminal box  52  of the terminal  34 . The housing socket  36  has a socket aperture  36   a  for receiving a ground pin  30   a  of the plug  30  of the electrical outlet  22 , and socket apertures  36   b  and  36   c  for receiving line and neutral pins  30   b ,  30   c , respectively, of the plug  30 . 
     The means for connecting the housing socket  36  to a power source includes a connector  54  for connecting wires from an electrical power cable to the housing terminal  34 . Connector  54  has connector gripper  54   a  for engaging an earth wire of the power cable, and connector grippers  54   b  and  54   c  for engaging line and neutral wires of the power cable, respectively. It will be understood that a wire from a power cable is connected to connector  54  by placing a bare end of the wire into a blind hole in which there is a gripper, e.g.  54   a , for securing the bare end. The means for connecting the housing socket  36  to a power source further includes internal wires  39  (shown schematically in chain-dotted outline) for connecting the grippers  54   a ,  54   b  and  54   c  to socket apertures  36   a ,  36   b  and  36   c , respectively. 
     Once received in the housing  24 , the electrical outlet  22  may be secured to the housing  24  by inserting a securing screw (not shown) through an aperture  57  extending through an end portion of the outlet  22  remote from the plug  30  (see FIGS.  1  and  2 ), and through a threaded mounting hole  58  (shown in FIG. 3) formed in back wall  42  of the housing  24 . 
     The electrical outlet  22  will now be described in more detail with reference to FIG.  3 . The electrical outlet  22  has a front  62 , a back  64  spaced from the front  62 , a pair of opposed sides  66 ,  68  extending between the front  62  and the back  64 , and a pair of ends  70 ,  72  extending between the front  62  and the back  64  and between the opposed sides  66 ,  68 . The sockets  28  are disposed in the front  62  and are electrically connected to plug  30  by internal wires  32 . The plug  30  consists of an earth pin  30   a , and line and neutral pins  30   b  and  30   c , which extend perpendicularly away from the end  72 . Between sockets  28  and plug  30  is a means for limiting the maximum current flowing from the plug  30  to the sockets  28  in the form of a conventional resettable breaker switch  74  (shown schematically in chain-dotted outline). The breaker switch  74  has a rocker switch  75  associated therewith. When the breaker switch  74  is tripped, rocker switch  75  can be used to reset it. It can also be used as a manual on-off switch for switching power on or off between plug  30  and sockets  28 . Also between sockets  28  and plug  30  is a conventional power spike and line noise protector  77  (also shown schematically) for filtering out power spikes and line noise reaching sockets  28 . Pins  30   a-c  of plug  30  are insertable in corresponding apertures  36   a-c  of the housing socket  36 . 
     Referring now to FIGS. 4 and 5, the assembly  20  includes an optional face plate  76  having a central opening  78 . The face plate  76  is attachable to the electrical outlet  22  as can be seen in FIG. 5 as follows. The electrical outlet  22  has a pair of ridges  80 ,  82  formed one to each side  66 ,  68  thereof. The face plate  76  includes a front member  84  and a pair of lugs  86 ,  88  integrally formed with the front member  84  and extending perpendicularly from a rearward side  90  thereof. Each lug  86 ,  88  has a channel  92 ,  94  for receiving a respective ridge  80 ,  82  of the electrical outlet  22  in a snap fit. The face plate  76  can be snapped onto the electrical outlet  22  when it is received inside the housing  24  thereby covering an outer periphery of the opening  40  of the housing  24  and exposing the sockets  28  of the electrical outlet  22  through the central opening  78  of the face plate  76 . 
     Once snapped on, the face plate  76  can be more permanently secured within the assembly  20  by inserting a pair of securing screws (not shown) through two sets of aligned apertures. A first set of aligned apertures consists of holes  96  and  98  formed in the front of terminal box  52  and the bottom of face plate  76 , respectively (see FIGS.  1  and  4 ). A second set of aligned apertures consists of holes  58 ,  57 , and  100 , extending through the back wall  42  of the housing  24 , a top portion of the electrical outlet  22 , and a top portion of the face plate  76 , respectively (see FIGS. 2,  1 , and  4 ). The securing screw extending through holes  58 ,  57 , and  100  also serves to secure the electrical outlet  22  to the housing  24 . 
     The housing  24  also has small apertures  102  in sides  44 ,  46  and in back  42  for attaching the housing  24  to a wooden stud or the like, with screws or nails, as is known in the art. 
     In use, the housing  24  is installed inside a cavity in a wall so that the opening  40  of the housing  24  communicates with an exterior of the wall through an opening in the wall. The housing  24  is mounted such that it lies substantially flush with the outside of the wall. This is the most usual installation in newly constructed establishments. When retrofitting an older establishment, the housing  24  may be mounted externally to the wall, on a beam or the like, as is known in the art. Connector  54  is then connected to an electrical power cable so that electrical power can be supplied to the housing socket  36 . 
     After installing the housing  24 , the electrical outlet  22  is inserted into the housing  24  with the plug  30  of the outlet  22  inserted into the housing socket  36 . The face plate  76  is then installed over the electrical outlet  22 . 
     The housing  24 , electrical outlet  22 , and face-plate  76  may be sold separately or as a kit, with requisite additional accessories such as securing screws. 
     The assembly of the present invention is useful for providing a plurality of outlets which are protected from power spikes and line noise and which have a resettable breaker right at the outlet  22 . Furthermore, if the circuitry for the power spike and line noise protector or breaker switch become defective, the electrical outlet  22  is easily replaced without having to damage the surrounding wall. 
     The above description of the preferred embodiment is by way of example only and shall not be used to limit the scope of the invention as defined by the claims herein. For example, The housing terminal  34  may be at the top of the housing  24 . Also, the housing  24  could be used horizontally so that the housing terminal  34  would be at one side of the housing  24 . 
     As an alternative to face plate  76 , a face plate  108  according to an alternative embodiment (shown in FIG. 6) may be used. The face plate  108  has individual apertures  110  in register with each of the sockets  28  thereby providing access to the sockets  28 . 
     Although connector  54  is shown on the side of housing  24 , it may be underneath (as shown in FIG. 8) or at the back of the housing  24 . FIG. 8 also shows the connector to be screw type connectors  103   a-c  as distinguished from the grippers of the first preferred embodiment. 
     Optionally, there may be electrical wires connecting connector  54  to a further terminal  105  at the top of the housing, as shown schematically in FIG.  7 . In such case, current flowing to connector  54  will flow not only to housing socket  36  but also to the further terminal  105 . By fitting an electrical power cable to grippers  104   a-c  of connector  104  of the further terminal  105 , current reaching the further terminal  105  may then be taken to another electrical outlet connected to the power cable. It will be understood that the further terminal  105  may be disposed in any suitable position on the housing (e.g. adjacent to connector  54  the first preferred embodiment) instead of being at the top of the housing  24  as shown in FIG.  7 . 
     The housing  24  and electrical outlet  22  may be made of conventional materials, e.g. metal and plastics, while the face plate  76  is preferably made of plastic material. Suitable plastics for the face plate  76  include ABS, high density polyethylene, polypropylene, and polystyrene. 
     The housing  24  may be mounted within a wall cavity in any manner known in the art. 
     Finally, the word “socket” used throughout the specification is herein defined to include any means for connecting an electrical connector of an appliance to an electrical outlet, or for connecting an electrical connector of an electrical outlet to a housing for the outlet, and shall not be construed to be limited to the particular structure shown in the drawings.