Patent Publication Number: US-2010116638-A1

Title: Socket assembly

Description:
CLAIM OF PRIORITY 
     This application claims the benefit of priority under 35 U.S.C. §119(e) to U.S. Provisional Application No. 61/113,832, filed Nov. 12, 2008, titled Socket Assembly, which application is also hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Various activities can be performed underground that require power. For example, a technician may enter the underground location at which work must be done via a manhole or other opening. The technician often requires power for the electric tools that are required to perform the work, such as a lamp to illuminate the area, an electric drill, a torch, etc. 
     In accordance with common practice, the technician often takes a receptacle, most likely with three #12 wires (hot, neutral and ground). The technician ties the ground and neutral wires together and attaches them to the system ground. To access power for their electric tools or other uses, the technician often drives a nail into a powered line, such as a 120v line and clips the hot wire to it. The hot wire thus becomes powered and an electric tool can be connected to the hot wire to provide power to the electric tool. Before the technician leaves the structure having the hot wire connected thereto, the technician may forget to remove the nail or he may remove the nail from the powered line and the receptacle, and seal and tape up the hot wire where the nail was removed. Such a practice can be dangerous to the technician as well as to persons subsequently coming into the location. For example, stray voltage from power sources in underground vaults can be a serious and deadly problem. Additionally, during each subsequent visit to this underground structure a new receptacle must be installed for power access. 
     Accordingly, it is desirable to provide a mechanism to provide power underground that overcomes these and other drawbacks of the current devices and methods. In particular, it is desirable to provide a permanent electrical source for use in an underground vault that can inhibit and/or eliminate stray voltage in the event water or other liquids envelope the power source and/or vault. 
     SUMMARY OF THE INVENTION 
     The present invention is directed towards a socket assembly for providing a power socket proximate a cable and/or cable joint, for example, at a location underground. The socket assembly preferably includes a hot lead connectable to the cable or cable joint to draw power therefrom, a ground lead and a neutral lead (or a single ground/neutral lead). The leads are connected to a socket to which a power plug can be connected. The socket and lead assembly is preferably potted to provide a water-tight seal. The assembly also preferably includes a cap for providing a water-tight seal over the exposed interface end of the socket. The socket assembly may also comprise an electronic shut off that turns off power to the socket after a pre-determined period of time. Another safety option would be to incorporate a GFI (Ground Fault Interrupter) to the socket assembly. The socket assembly of the present invention provides a fully submersible power source which does not have to be removed after each visit to the underground vault. 
     Other objects and features of the present invention will become apparent from the following detailed description, considered in conjunction with the accompanying drawing figure. It is to be understood, however, that the drawings are designed solely for the purpose of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The particular features and advantages of the invention as well as other objects will become apparent from the following description taken in connection with the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a socket assembly, installed on a cable joint, in accordance with an embodiment of the invention; 
         FIG. 2  is a side view of a socket assembly in accordance with an embodiment of the invention, with a removable cap shown in a closed position; 
         FIG. 3  is a perspective view of the socket assembly of  FIG. 2 , with the removable cap shown in an open position; 
         FIG. 4  is a perspective view of a socket assembly with a removable cap having an open face; 
         FIG. 5  is a cross sectional view of the socket assembly of  FIG. 2 ; 
         FIG. 6  is a perspective view of a socket and cable joint assembly in accordance with an embodiment of the invention. 
         FIG. 7  is a cross sectional view of a socket assembly with an integrally formed shut off device in accordance with an embodiment of the invention; 
         FIG. 8  is a cross sectional view of a socket assembly with a shut off device in accordance with an embodiment of the invention; and 
         FIG. 9  is a circuit schematic of the shut off device of  FIGS. 7 and 8  in accordance with an embodiment of the invention. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Certain exemplary embodiments of the present invention will now be described with reference to the drawings shown in  FIGS. 1-9 . In general, such embodiments relate to a socket assembly  100  that can be electrically and physically connected to a cable or cable joint  20 . The cable or cable joint  20  can be connected to a power source and thus provide power, such as electric power, to the socket assembly  100 . The socket assembly  100  of the present invention can be connected directly to a cable, and can also be connected to various types of cable joints. While  FIGS. 1 and 6  depict a specific cable joint  20  for use with the socket assembly  100  of the present invention, the socket assembly  100  can be used with other types of cable joints such as, for example, crab joints, insulated crab joints and other joints that are known and used in the industry. 
     As shown in  FIGS. 1-6 , the socket assembly  100  can include a socket body  112  having a socket interface  110 , the socket body  112  being connected to a hot lead  102 . The socket assembly  100  may also include a ground lead  104  and a neutral lead  106  as seen in  FIG. 1 , or may include a single ground/neutral lead  108  as seen in  FIG. 6 . In a preferred embodiment, the hot lead  102  is larger than the other leads so that the socket assembly  100  can be rigid when installed. The connection between the leads and the socket body, and in particular between the hot lead  102  and socket body  112 , is preferably potted to provide a water tight seal between the leads and in particular the hot lead  102  and the socket body  112 . The socket interface  110  is preferably constructed and arranged to accept a power plug or other interface of a device, such as an electric device, to the socket body  112 . For example, the socket interface  110  can include a plurality of apertures through which a plurality of prongs from the power plug can be inserted into the socket body  112 . Once the power plug is connected to the socket body  112 , electricity can flow between the electric device and the socket assembly  100 , and more specifically, between the power source and the electric device through the cable or cable joint  20  and the socket assembly  100 . 
     The hot lead  102  is preferably connected to the socket body  112  at a first end and can connect to the cable or cable joint  20  at a second end. The hot lead  102  can be electrically connected to the cable or cable joint in any number of ways. For example, when used with insulated crab joints, the hot lead  102  can be crimped to the cable joint and the connection can be insulated using the insulation of the crab joint. The connection could also be taped. 
     In accordance with an exemplary embodiment, by way of example as seen in  FIGS. 1 and 6 , the hot lead  102  can be connected to the cable joint  20  at a suitable connecting element, such as a leg  22  of the cable joint  20 . For example, hot lead  102  can be inserted into a copper tube or other receiving element of leg  22 , and the copper tube can be compressed onto hot lead  102 . Once connected, electricity can preferably flow between the cable or cable joint  20  and the socket body  112  via hot lead  102 . 
     The socket assembly  100  preferably includes a ground lead  104  and a neutral lead  106 . The ground lead  104  is preferably constructed and arranged to connect to a grounding element, and the neutral lead  106  is preferably constructed and arranged to connect to a neutralizing element. The grounding element and the neutralizing element are preferably located proximate the cable joint  20 . 
     The socket assembly  100  is preferably insulated, for example, by a rubber casing. Preferably, as seen in  FIGS. 1-8 , the socket assembly  100  includes a cap  114  which is constructed and arranged to cover the socket interface  110  when the cap  114  is in the closed position. The cap  114  may be removable to expose the socket interface  110  so that the plug or other device can be connected to the socket assembly  100 . In an alternative embodiment, as seen in  FIG. 4 , the cap  114  may have an open face for access to the interface  110  without having to remove the cap. In accordance with an exemplary embodiment, the cap  114  includes a cavity in which a portion of the socket body  112  including the socket interface  110  can be received. 
     The cap  114  can include a threaded inner wall and the body  112  can include a threaded outer wall such that the cap  114  can be screwed onto the body  112 . Alternatively, the cap  114  can engage the body  112  via a friction fit or other mechanism without deviating from the scope of the invention. Preferably, the cap  114  includes grooves  114   a , which may facilitate gripping the cap  114  to rotate it, slide it over the body  112 , or otherwise manipulate the cap  114 . The body  112  can also include one or more grooves  112   a , which may facilitate gripping the body  112 . 
     Preferably, when the cap  114  is in the closed position, the cap  114  creates a seal such that water and other materials cannot seep in between the body  112  and cap  114  thus protecting the socket interface  110 . Therefore, the apertures  111  of the socket interface  110  can be protected from water and other debris when the cap is installed on the body. 
     Referring to  FIGS. 3-7 , one or more sealing rings  122 ,  123 ,  124  can be provided on the outer periphery of the body  112 . Preferably, the sealing rings are O-rings that can contact the inner wall of the cap  114  to create a seal between the body  112  and the cap  114 . Preferably, the sealing rings  122 ,  123 ,  124  extend radially outward from the body  112 . More specifically, the sealing rings  122 ,  123 ,  124  can have an outer diameter greater than the outer diameter of the body  112 , to help seal the gap between the cap  114  and the body  112 . In accordance with a preferred embodiment, sealing rings  122 ,  123 ,  124  can be formed of rubber or other material that can be deformed, contracted, or otherwise adjusted to permit the cap  114  to be positioned over the sealing rings  122 ,  123 ,  124  while maintaining a sealing contact between the sealing rings  122 ,  123 ,  124  and the cap  114 . 
     Referring to  FIGS. 1-8 , a chain  120  can connect the cap  114  to the body  112 , so that when the cap  114  is removed from the body  112 , the cap  114  is not separated from the body  112  and does not get lost. Preferably, the chain  120  is connected to the body  112  via a first O-ring  124  and to the cap  114  via a second O-ring  126 . An O-ring may be more resilient, facilitate manufacture, or provide other benefits compared to attaching the chain  120  directly onto the body  112  or the cap  114 . Other means of connecting the chain  120  to the body and the cap are envisioned without departing from the scope of the invention. For example, another preferred alternative is a rigid ring that will not easily separate from the cap or the body. It is to be also understood that other mechanisms for connecting the cap  114  to the body  112 , such as a strap, elastic, etc. can be provided instead of or in combination with the chain  120  without deviating from the scope of the invention. 
     Referring to  FIG. 6 , in accordance with an embodiment, the socket assembly  100  can include a single neutral-and-ground lead  108 , instead of separate ground lead  104  and neutral lead  106 . The neutral-and-ground lead  108  can be connected to a ground element, a neutral element, or a neutral-and-ground element. 
     By way of non-limiting example, as seen in  FIGS. 1 and 6 , an embodiment of the cable joint  20  can include a U-shaped base  24  connected to the plurality of legs  22 , wherein each leg  22  is constructed to receive a cable. In the embodiment illustrated, cable joint  20  has six legs  22  on each side of base  24 . Legs  22  can be connected via compression connections to base  24 . Preferably, each side of base  24  also includes at least one non-fused connector  26  having a cable  26   a  to create a “ring” bus for the purpose of balancing the electric load on more than one crab joint of the same phase. Cable  26   a  can be connected to another cable  26   a  of a nearby cable joint of the same phase (A,B,C) thereby creating the “ring bus” (i.e., an electrical reference point). An example of a cable joint  20  is provided in copending U.S. patent application Ser. No. 12/207,267, the contents of which are incorporated in its entirety by reference herein. 
     Alternatively, hot lead  102  can be connected to a different device or mechanism, for example a cable or insulated crab joint, from which power can be provided to the device connected to the socket interface  110  without deviating from the scope of the invention. Furthermore, whereas the cable joint  20  has been described herein as being connected to one or more legs  22 , it is to be understood that other variations are contemplated as a matter of application specific design choice. By way of non-limiting example, cable or base  24  may be connected directly to hot lead  102  or via a connector or other device without deviating from the scope of the invention. 
     As seen in  FIGS. 7-9 , the socket assembly  100  may also include a shut off device  200  that can turn off power to the socket interface  110  or a GFI that can interrupt power to the receptacle if more current is sensed in the hot lead as opposed to the ground and/or neutral leads. In a preferred embodiment, the shut off device is designed to automatically turn off power to the socket interface after a predetermined period of time. The shut off device  200  (or GFI device) can be formed integrally with the socket body  112  as seen in  FIG. 7 , or may be formed as a separate element along hot lead  102  as seen in  FIG. 8 . In either embodiment, the interface between hot lead  102  and shut off device  200  is potted to provide a water tight seal. 
     In a preferred embodiment as seen in  FIG. 9 , shut off device  200  includes a power supply  202 , a processor  204 , and a contactor  206 . When the shut off device is engaged, for example by engaging a sealed pushbutton  210 , the processor  204  turns on the contactor  206  to provide power to socket body  112 . In a preferred embodiment, after a predetermined period of time the processor can turn off the contactor  206  to prevent power to socket body  112 . In a preferred embodiment, the contactor  206  includes a switch  210  controlled by an actuator  208 . In a preferred embodiment, the power supply  202  is electrically connected to the hot lead  102  and neutral lead  106 , and the hot lead  102  is also connected to one side of switch  210 . The power supply  202  powers the processor  204 , which powers the actuator  202  for actuating the switch  210  to complete or disconnect the power based on a predetermined period of time. The shut off device  200  provides an additional and important safeguard against stray voltage that can be caused by water buildup around the cable and/or joint by turning off power to the socket body after a period of time, thus ensuring a safe and properly insulated voltage source. 
     The examples provided are merely exemplary, as a matter of application specific to design choice, and should not be construed to limit the scope of the invention in any way. Thus, while there have been shown and described and pointed out novel features of the present invention as applied to preferred embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and details of the disclosed invention may be made by those skilled in the art without departing from the spirit of the invention. For example, the type of cable and/or cable joint, the number of socket interfaces provided for each socket cable, the number of socket assemblies connected to a cable joint, the number of socket cables connected to a socket interface, the type of cap for covering the socket interface, the shape of the cable joint, the number of legs or ring buses provided thereon, sides to the base, etc. can be varied without deviating from the scope of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto. 
     It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.