Abstract:
An electrical connector adapted for portable power distribution systems and other applications in various embodiments includes a versatile lug which may be selectively and repeatedly coupled to a stranded or other conductor and mounted and re-mounted on a bus bar or other mounting surface via a variety of attachment features on the lug. The lug offers numerous ways to attach it to a power bus and is designed for thousands of installations and re-installations each requiring the appropriate torque on the connector rather than a few such installations for which a known connector is designed and rated. The attachment features included in various embodiments of the lug connector allow for horizontal, vertical, side by side and edge clamping among other mounting configurations.

Description:
[0001]    This claims the benefit of U.S. Provisional Application Ser. No. 62/356,803, filed Jun. 30, 2016 and hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Various operating centers which employ complex electrical and/or electronics equipment have typically been constructed by first erecting a suitable structure for housing the electrical and electronics equipment at the industrial or commercial installation site. After the operating center is erected, the various cabinets, panels and other units which contain the electrical and electronics equipment are transported to the installation site and installed in the operating center. After the various cabinets, panels and other units are mounted properly, they are then inter-wired and interconnected with one another to form a complete set of control system equipment within the operating center. The control system equipment is thereafter tested to determine that all the proper interconnections have been made and that the equipment is operating as desired. Any necessary adjustments or calibrations of the equipment are made at this time. 
         [0003]    Construction and other projects require electric power to be distributed to various tools and components. Once normal electric service is provided to a building and the electric wiring for the building is completed, providing electric power for tools and components is simple. But prior to the completion of the buildings&#39; electric wiring and/or prior to the establishment of regular electric service, providing electric power to the construction site is more problematic. Several prior art devices have been developed to provide temporary power to users at a construction site or related location, some examples of which are provided by Power Temp Systems, Inc. out of Houston, Tex., www.powertemp.com. 
         [0004]    During building or repair tasks at construction sites or other workplaces, it is often necessary to provide temporary electrical power for operating many lights, tools or other devices at the same time when permanent power distribution facilities have not yet been installed or are out of service because of damage or equipment failure. In some cases, the temporary power distribution apparatus must be carried through or used in a confined space that does not afford much room for the apparatus. 
         [0005]    Systems are known for distributing AC or DC voltage and current to multiple loads from one or more sources on a power bus. The simplest form of such a system is a multiple connector box at the end of an extension power cord. A more complex system is a connector affixed to a printed circuit board via pins extending from the connector into receiving holes in the printed circuit board. Terminal blocks with isolated positive and negative rails from which voltage is carried to appliance loads via insulated multiple strand conductor wire is yet another example of a system for distributing AC or DC power. 
         [0006]    Where insulated wire pairs are used, the connections are made by affixing terminals or lugs to the ends of the wires. Some terminal blocks provide studs on which the terminals can be secured using nuts, set screws and/or lock washers. Systems such as these have little or no provision for rapid disassembly or assembly. Electrical connectors and lugs typically employed in such settings are not suited for multiple installations, removals and re-installation. 
         [0007]    In systems using terminal blocks, the task of affixing terminals to wires or terminals to the studs is time consuming and subject to defects if proper procedures such as, cleaning or clearing the contacts or studs of dirt, snow, ice, and corrosion followed by operations such as torquing nuts on studs, are not followed. If a technician is connecting a DC service from a lead acid battery or from another low impedance voltage source capable of driving multiple horsepower DC motor loads, or loads such as a heavy-duty arc welder, a mistake made by the technician in connecting the polarity of the electrical service can be catastrophic. 
         [0008]    Conventional systems for connecting one or more sources to more than one load include those that have terminal blocks with leads to service the appliance loads, clips and electrical connectors, barrier strips, connectors with pins that preclude polarity errors, terminal blocks with terminal connectors that preclude improper orientation, devices for selectively interconnecting a series of connectors, extension cords, multiple outlet boxes, and power strips. However, none of those systems, either separately or in combination, offer an integrated system and components for rapidly and reliably connecting and disassembling, disconnecting and reconfiguring power to respective loads, and for servicing the power from one or more respective voltage sources. The electrical connectors are not versatile and often require specially designed lugs for proper installation. This often increases required inventory and makes the set-up and removal procedures more difficult. 
       SUMMARY OF THE INVENTION 
       [0009]    These and other shortcomings in the prior art have been addressed by various embodiments of this invention which include an electrical connector adapted for portable power distribution systems and other applications. In various embodiments, this invention includes a versatile lug which may be selectively and repeatedly coupled to a stranded or other conductor and mounted and re-mounted on a bus bar or other mounting surface via a variety of attachment features on the lug. While known standard lugs have provision for a single mounting style, the lug of this invention in various embodiments is more versatile and accommodates a wide range of mounting schemes and configurations. This invention differs from normal connectors due to the numerous ways to attach it to a power bus and the fact that it is designed for thousands of installations and re-installations each requiring the appropriate torque on the connector rather than a few such installations for which a known connector is designed and rated. 
         [0010]    The attachment features included in various embodiments of the lug connector of this invention allow for horizontal, vertical, side by side and edge clamping among other mounting configurations. The ability to provide for such versatile mounting schemes and configurations allows for reduced inventory and elimination of specialized and single use electrical connectors which is particularly advantageous when used in a temporary or portable power distribution system. Various embodiments of this invention provide for attachment features on all sides of the lug to land (mount) compression or mechanical connectors. The invention accommodates stud mounted connectors and is designed for mounting provisions for isolated applications. Simultaneous hardwire and multiple eyelet connections are possible with the lug of this invention in various embodiments. A user may tie into the lug and simultaneously bolt to a cable with eyelets. 
         [0011]    These and other features and benefits of various embodiments of this invention are realized to address and overcome the identified and other shortcomings of the prior art. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
           [0013]      FIG. 1  is a perspective view of one embodiment of an electrical connector lug adapted for various applications including portable power distribution systems according to this invention; 
           [0014]      FIGS. 1A-1D  are perspective views of alternative embodiments of the lug of  FIG. 1  according to this invention; 
           [0015]      FIG. 2  is a perspective view of a stranded conductor for coupling to the lug according to this invention; 
           [0016]      FIG. 3  is a perspective view of an exemplary portable power distribution center in which various embodiments of the lug according to this invention may be utilized; 
           [0017]      FIG. 4  is a perspective of an exemplary installation utilizing the lug according to various embodiments of this invention connected to a slotted bus bar; 
           [0018]      FIGS. 5A-5L  are top plan views of various configurations, mounting schemes and installations utilizing the lugs of various embodiments of this invention for electrical connection; and 
           [0019]      FIG. 6  is a perspective view of an installation using a number of lugs of various embodiments of this invention mounted on a bus bar. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0020]    Referring to  FIGS. 1-1D , various embodiments of a lug electrical connector  10  according to this invention are shown. The lug  10  includes a metallic terminal lug body  12  which may be copper, aluminum or another suitable material well known to those of ordinary skill in this art. The lug  10  includes a set screw  14  which is received within a threaded set screw bore  16  of the lug  10  oriented generally axially or longitudinally on the lug body  12 . The set screw  14  may be a headless set screw having a hexagon-shaped recess  18  or a set screw with a head  20  having a hexagon-shaped recess  18  and an external configuration adapted for use with a wrench or other tool for securing the set screw  14  in the lug body  12 . The set screw  14  may be of the type disclosed in U.S. patent application Ser. No. 15/139,416, filed Apr. 27, 2016 or in U.S. Pat. No. 7,699,669 issued Apr. 20, 2010, each of which is hereby incorporated by reference in its entirety. 
         [0021]    The lug body  12  of  FIGS. 1-1D  includes a laterally extending conductor bore hole  22  extending from opposite side faces  24 ,  24  of the body  12  and generally perpendicular to the set screw bore  16 . The set screw  14  is seated within the threaded bore  16  extending longitudinally from an upper face  26  of the body  12  and in communication with the conductor bore  22 . The threaded set screw bore  16  extends into the body  12  and the conductor bore  22  and terminates therein. 
         [0022]    The conductor bore hole  22  is adapted to receive the multiple strands  28  of a conductor  30  as shown in  FIG. 2 . The conductor  30  includes the multiple strands  28  covered by a sheath  32  which may be removed from the terminal end of the conductor  30  for appropriate electrical connection by the conductor strands  28  with the lug  10 . 
         [0023]    The lug  10  according to various embodiments of this invention also includes several attachment features  34  in the lug body  12  which are each adapted for connecting the lug  10  to the appropriate compatible equipment providing for electrical connection. One attachment feature  34  is shown in  FIGS. 1 and 1B  as a threaded bore hole  34   a  extending axially and longitudinally from a bottom face  36  of the lug body  12 . This attachment feature  34   a  is adapted to receive a threaded bolt, stud or other mechanical fastener therein for mounting the lug body  12  to a slotted bus bar  38  via an adapter  40  as shown particularly in  FIG. 4  or another appropriate mounting arrangement with or without the adapter  40 . The fastener  35  which may be used to mate with the attachment feature  34  may take any one of a variety of forms and is generally identified by reference numeral  35  herein. The component to which the lug  10  of various embodiments of this invention is to be mounted will generally be identified by reference numeral  38  and one of ordinary skill in the art will appreciate that such a component  38  may take a wide variety of shapes, configurations and functions and is not a restriction on this invention. One example of such a component  38  is a bus bar as disclosed in U.S. patent application Ser. No. 15/376,762 filed Dec. 13, 2016 and hereby incorporated by reference in its entirety. 
         [0024]    In various embodiments, the cross-sectional configuration of the lug body  12  is generally square. Likewise, the top and bottom faces  26 ,  36  of the lug body  12  are generally square while each side face  24  of the lug body  12  is generally rectangular. Two additional attachment features  34  may also be provided in the bottom face  36  of the lug body  12  which comprise small threaded bore holes  34   b  each of which is adjacent a corner of the bottom face  36  of the lug body  12  and positioned proximate opposite corners of the lug body  12  as shown generally in  FIGS. 1 and 1B . These attachment features  34   b  are typically used in combination with one another and are adapted to receive smaller diameter bolts, screws or other mechanical fasteners  35  which are used to mount the lug body  12  in various mounting schemes, some of which are demonstrated in  FIGS. 4-6 . 
         [0025]    Additional attachment features  34  which are included in various embodiments of the lug  10  according to this invention are shown in  FIGS. 1A-1D  in the form of threaded (or unthreaded) bore holes  34   c  extending through the lug body  12  from opposite side faces  24  of the lug body  12 . These side face lug bore holes  34   c  intersect beneath the conductor bore hole  22  and provide for attachment of a threaded or unthreaded bolt, stud or other mechanical fastener  35  for mounting the lug body  12 . While the intersecting threaded bore holes  34   c  extending between opposite side faces  24  of the lug body  12  are shown in  FIGS. 1A-1D , one of ordinary skill in the art will appreciate that two such bore holes are not required and only one such bore hole may extend between either pair of the opposite faces  24  of the lug body  12  according to various embodiments of this invention. Moreover, if two such threaded bore holes are provided, they may or may not be of the same thread or diameter specification. For example, a side face threaded bore hole  34   d  is shown in  FIG. 1  having a smaller diameter than those of the side face threaded bore holes  34   c  of  FIGS. 1A-1D . Moreover, the bore holes  34   c  may be unthreaded and provide for insertion of a bolt or other fastener to mount multiple lugs  10  together as shown in  FIG. 6 . The lugs  10  as shown in  FIG. 6  may or may not include an extending tang  47  for mounting the lug  10  and/or attached lugs  10  to a bus bar  38  or the like. The lugs  10  of  FIG. 6  have the conductor bore hole  22  on a longitudinal end of the lug body  12  and the threaded bore hole  16  in which the set screw  14  is seated on a side face  24  of the lug body  12 . The mounting arrangement of  FIG. 6  includes four lugs  10 , two of which include the tang  47  and two of which do not and any number of lugs  10  may be utilized in a mounting arrangement. 
         [0026]    An additional attachment feature  34  which may be provided in various embodiments of the lug  10  according to this invention is a slot  34   e  extending generally perpendicular to the conductor bore hole  22  ( FIGS. 1C-1D ) or parallel (not shown) and on the bottom face  36  of the lug body  12  as shown in  FIGS. 1C-1D . The slot  34   e  bifurcates the lower portion of the lug body  12  into two posts  42  and allows for the lug body  12  to be mounted on a bar  38  as shown in  FIG. 5L . The two posts  42  formed on either side of the slot  34   e  may each have additional attachment features  34  including a pair of threaded or unthreaded slot bore holes  34   f  extending into the post  42  as shown in  FIG. 1D . 
         [0027]    These and other attachment features  34  may be provided with the lug  10  according to various embodiments of this invention in various combinations or individually as is appropriate for the particular mounting requirements. Moreover, each of the attachment features may be threaded or unthreaded as appropriate. 
         [0028]    The lug  10  according to this invention may be mounted to the slotted bus bar  38 , an example of which is shown in  FIGS. 4 and 6 , and disclosed in U.S. Pat. No. 9,698,578, issued on Jul. 4, 2017 and hereby incorporated by reference in its entirety. A slot  50  may be utilized for proper mounting of the lug  10  to the slotted bus bar  38 . 
         [0029]    One application of the lug  10  according to this invention may be for connecting conductors  30  as shown in  FIG. 2  to a portable and/or temporary power distribution center  46 , one example of which is shown in  FIG. 3 . However, those of ordinary skill in the art will appreciate that the lug  10  of this invention may be utilized in many other applications in addition to the power distribution center  46  shown in  FIG. 3 . 
         [0030]    Various installation schemes for the lug  10  according to various embodiments of this invention may utilize an adapter  40  to which the lug body  12  is connected for mounting the lug  10  and adapter  40  to a bus bar  38  or the like. The adapter  40  may take any one of a variety of shapes and configurations and may include an extension  48  which is to be seated within a slot  50  of a slotted bus bar  38  as shown, for example, in  FIG. 6 . The adapter  40  may also include any number, size, arrangement and configuration of threaded or unthreaded bore holes  52  which allow for mounting with the various components as may be required according to a particular installation. 
         [0031]    From the above disclosure of the general principles of this invention and the preceding detailed description of at least one embodiment, those skilled in the art will readily comprehend the various modifications to which this invention is susceptible. Therefore, we desire to be limited only by the scope of the following claims and equivalents thereof.