Patent Publication Number: US-9431766-B1

Title: Keyed power connector

Description:
FIELD 
     The present disclosure relates generally to electrical connectors, and more specifically to keyed electrical connectors. 
     BACKGROUND 
     Installation of electrical power feeders using standard lugs and terminal studs exposes systems to risk of damage due to misconnection of lugs to studs. Various efforts to address this challenge include labels, which tend to fall off, color-coding, which fades and/or discolors over time, and varying thread sizes of studs, which increases the number and variety of tools and hardware used in assembly and maintenance. 
     SUMMARY 
     The forgoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated herein otherwise. These features and elements as well as the operation of the disclosed embodiments will become more apparent in light of the following description and accompanying drawings. 
     A keyed power connection system is disclosed. The keyed power system may have a connector. The connector may include a connector fastening portion having a captive fastener, a connector electrical conduction portion including a connector body configured to retain the connector fastening portion in movable communication with the connector, and a connector keying portion having a keyed aperture forming an opening in and defined by the connector body and including a keyed connector diameter. 
     A keyed power connection system may have a terminal stud. The terminal stud may include a terminal stud keying portion having a post including a cylindrical boss configured to support a terminal stud fastening portion, a keyed stud diameter including a diameter of the post, and a terminal stud electrical conduction portion having a terminal stud conductive surface disposed annularly about the post. The terminal stud fastening portion may include a fastener receiving threaded bore having a cylindrical channel defined by the post and extending axially into the post. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The subject matter of the present disclosure is particularly pointed out and distinctly claimed in the concluding portion of the specification. A more complete understanding of the present disclosure, however, may best be obtained by referring to the detailed description and claims when considered in connection with the drawing figures, wherein like numerals denote like elements. 
         FIG. 1  illustrates a block diagram of a keyed power connection system, according to various embodiments; 
         FIG. 2  illustrates a side view of a keyed power connection system, according to various embodiments; and 
         FIG. 3  illustrates an isometric view of a keyed power connection system, according to various embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     The detailed description of exemplary embodiments herein refers to the accompanying drawings, which show exemplary embodiments by way of illustration. While these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice embodiments of the disclosure, it should be understood that other embodiments may be realized and that logical changes and adaptations in design and construction may be made in accordance with this invention and the teachings herein. Thus, the detailed description herein is presented for purposes of illustration only and not limitation. The scope of the disclosure is defined by the appended claims. For example, the steps recited in any of the method or process descriptions may be executed in any order and are not necessarily limited to the order presented. Furthermore, any reference to singular includes plural embodiments, and any reference to more than one component or step may include a singular embodiment or step. Also, any reference to attached, fixed, connected or the like may include permanent, removable, temporary, partial, full and/or any other possible attachment option. Additionally, any reference to without contact (or similar phrases) may also include reduced contact or minimal contact. 
     Furthermore, any reference to singular includes plural embodiments, and any reference to more than one component or step may include a singular embodiment or step. Surface shading lines may be used throughout the figures to denote different parts but not necessarily to denote the same or different materials. 
     Power distribution systems, such as on vehicles (e.g., aircraft), often involve large gauge electrical power feeders. Such large gauge feeders are often connected via lugs attached to terminal studs, and due to their large gauge are often not connected via multi-conductor connectors. 
     However, such connections may potentially be misconnected. For instance, there may be multiple of such connections in relative proximity. For instance, a power feeder and a power return, or multiple phase power feeders, and/or the like may be located in close proximity. During maintenance operations, multiple such connections may be disconnected and reconnected. Thus, it is possible that lugs may be attached to the incorrect terminal studs. Various strategies to address this challenge are presented herein. For instance, a connector may be sized to only receive studs of corresponding size and may be associated with a captive fastener. Thus, various different connectors may be differently sized to prevent misconnection. Moreover, because the fastener is captive, the fastener is less subject to being lost. Furthermore, because the connector itself provides the keying rather than, for instance, the fastener, a single tool of a single size may be used to tighten/loosen connectors of a variety of different sizes, because differently sized connectors may have similarly sized fasteners. 
     With reference now to  FIG. 1 , a keyed power connection system  100  may comprise a connector  1  and a terminal stud  2 . The keyed power connection system  100  may enable the connection and disconnection of electrical power conducted between the connector  1  and the terminal stud  2  and may further prevent misconnection of connector(s)  1  to incorrect terminal stud(s)  2 . 
     The connector  1  may comprise a connector fastening portion  10 , a connector electrical conduction portion  20 , and a connector keying portion  30 . Similarly, the terminal stud  2  may comprise a terminal stud keying portion  40 , a terminal stud electrical conduction portion  45 , and a terminal stud fastening portion  50 . 
     The connector fastening portion  10  and the terminal stud fastening portion  50  may selectably interconnect and disconnect to hold the connector electrical conduction portion  20  in selectable physical contact with the terminal stud electrical conduction portion  45 . In this manner, electrical power may be conducted between the connector  1  and the terminal stud  2 . Moreover, the connector keying portion  30  and the terminal stud keying portion  40  may interact to permit the interconnection of the connector  1  to a corresponding terminal stud  2  while preventing the interconnector of the connector  1  to an incorrect terminal stud  2 . 
     With reference now to  FIGS. 1, 2 and 3 , various aspects of the connector  1  and the terminal stud  2  are discussed in further detail. 
     A connector fastening portion  10  of a connector  1  may comprise a captive fastener  11 . A captive fastener  11  may comprise a threaded bolt extending through a portion of the connector  1 , for instance, through an opening in the top of the connector  1  and extending into the connector electrical conduction portion  20 . The captive fastener  11  may be threaded to correspond to the terminal stud fastening portion  50  of a terminal stud  2 . Thus, the captive fastener  11  may be connected/disconnected from the terminal stud fastening portion  50  of the terminal stud  2 , thereby holding the connector electrical conduction portion  20  of the connector  1  in physical connection with the terminal stud electrical conduction portion  45  of the terminal stud  2 . 
     A connector electrical conduction portion  20  of a connector  1  may comprise a connector body  21 . A connector body  21  may comprise a housing configured to retain the connector fastening portion  10  (e.g., the captive fastener  11 ) in movable communication with the connector  1 . For example, the captive fastener  11  may extend through a hole in the connector body  21  so that the captive fastener  11  extends through the connector body  21  and is positioned to interface with the terminal stud  2 . The connector body  21  may be further configured to support the connector conductive surface  22  in a desired position, such as to provide rigidity to the connector conductive surface  22  when positioned in physical contact with the terminal stud conductive surface  46  of the terminal stud electrical conduction portion  45 . In various embodiments, the connector body  21  may comprise metal, although in further embodiments, it may comprise ceramic, or plastic, or may comprise coatings, such as a metal coated with a ceramic or plastic and/or the like. For instance, the connector body  21  may be conductive and may be pressed into mechanical contact with a corresponding plane of a post  41  such as may surround the base of the post  41  from which the post  41  orthogonally extends. 
     A connector electrical conduction portion  20  may comprise a connector conductive surface  22 . The connector conductive surface  22  may comprise an integral portion of the connector body  21 , for example, such as for connector body  21  made of a conductive material. The connector conductive surface  22  may comprise an annular portion of a cylindrical void defined by the connector body  21  and arranged to receive at least a portion of a terminal stud  2 . In various embodiments, the connector electrical conduction portion  20  may comprise a connector conductive surface  22  comprising an insert. For instance, the connector conductive surface  22  may comprise an annular insert disposed within an aperture defined by the connector body  21  and arranged to receive at least a portion of a terminal stud  2 . 
     A connector keying portion  30  of a connector  1  may comprise a connector keyed aperture  31 . The connector keyed aperture  31  may comprise an opening in and defined by the connector body  21 . The connector keyed aperture  31  may provide a passage for a portion of the terminal stud  2  to pass into the connector  1  so that the connector electrical conduction portion  20  and the terminal stud electrical conduction portion  45  may make physical contact with one another. The connector keyed aperture  31  may comprise a shape corresponding to the shape of the terminal stud  2 . For instance, the connector keyed aperture  31  may comprise a circular opening onto a cylindrical void defined by the connector body  21 . In various embodiments, the connector keyed aperture  31  may comprise any shape as desired. 
     A connector keying portion  30  may comprise a keyed connector diameter  33 . A keyed connector diameter  33  may comprise a diameter of the connector keyed aperture  31 . The keyed connector diameter  33  may be sized to correspond to a measurement of the terminal stud  2 . For example, the keyed connector diameter  33  may comprise a dimension corresponding to a keyed stud diameter  42  of a terminal stud keying portion  40  of a terminal stud  2 . In various embodiments, the keyed connector diameter  33  comprises the same dimension as the keyed stud diameter  42  plus a tolerance. For example, by changing the keyed connector diameter  33  and the keyed stud diameter  42  by a selected increment (for instance 1 mm), the connector  1  may be configured to properly connect only to those terminal studs  2  having a corresponding keyed stud diameter  42 . In various embodiments, for example, those wherein the keyed stud diameter  42  is variable in 1 mm increments, the keyed connector diameter  33  corresponds to the same dimension plus a tolerance of, for instance, 0.1 mm or 0.01 mm. or 0.5 mm or 0.05 mm, or any tolerance as desired, allowing for the connector  1  to slip over and receive a portion of the terminal stud  2 . 
     A connector keying portion  30  may comprise a connector alignment chamfer  32 . A connector alignment chamfer  32  may comprise an annular chamfer immediately outward of the connector keyed aperture  31  and defined by the connector body  21 . The connector alignment chamfer  32  may facilitate seating of the connector  1  on to a terminal stud  2  and may facilitate guidance of a portion of the terminal stud  2  into the connector  1 . For instance, the connector alignment chamfer  32  may correspond to the same dimension as the keyed stud diameter  42 , plus a tolerance of, for instance, 0.1 mm or 0.01 mm. or 0.5 mm or 0.05 mm, plus an additional tolerance of, for instance, 0.1 mm or 0.01 mm. or 0.5 mm or 0.05 mm, or any tolerance as desired to facilitate manual alignment and guidance to the connector  1  and the terminal stud  2  together. 
     Having discussed aspects of the connector  1  in detail, focus is directed to the terminal stud  2 . Particularly, focus is given to the terminal stud keying portion  40 , the terminal stud electrical conduction portion  45 , and the terminal stud fastening portion  50 . 
     A terminal stud keying portion  40  of a terminal stud  2  may comprise a post  41  configured to support a terminal stud fastening portion  50  (e.g., the fastener receiving threaded bore  51  and/or fastener receiving counter bore  52 ) whereby a connector fastening portion  10  (e.g., captive fastener  11 ) of a connector  1  is received. A post  41  may comprise a fixture, such as a cylindrical boss, arranged to support the terminal stud electrical conduction portion  45  in a desired position, such as to provide rigidity to the terminal stud conductive surface  46  when positioned in physical contact with the connector conductive surface  22 . In various embodiments, the post  41  comprises metal, although in further embodiments, it may comprise ceramic, or plastic, or may comprise coatings, such as a metal coated with a ceramic or plastic and/or the like. 
     A terminal stud keying portion  40  may comprise a keyed stud diameter  42 . A keyed stud diameter  42  may comprise a diameter of the terminal stud  2 . The keyed stud diameter  42  may be sized to correspond to a measurement of the connector  1 . For example, the keyed stud diameter  42  may comprise a dimension corresponding to a keyed connector diameter  33  of a connector keying portion  30  of a connector  1 . In various embodiments, the keyed stud diameter  42  comprises the same dimension as the keyed connector diameter  33  minus a tolerance. For example, by changing the keyed connector diameter  33  and the keyed stud diameter  42  by a selected increment (for instance 1 mm), the terminal stud  2  may be configured to properly connect only to those connectors  1  having a corresponding diameter, allowing for the connector  1  to slip over and receive a portion of the terminal stud  2 . 
     A terminal stud keying portion  40  may comprise a terminal stud alignment chamfer  43 . A terminal stud alignment chamfer  43  may comprise an annular chamfer disposed at the tip of the post  41 . The terminal stud alignment chamfer  43  may facilitate seating of the connector  1  on to a terminal stud  2  and may facilitate guidance of the connector  1  over the terminal stud  2 . For instance, the terminal stud alignment chamfer  43  may correspond to the same dimension as the keyed stud diameter  42  at one end of the annular chamfer, then comprise a reduced diameter at an outermost end of the post  41  (e.g., an axially outermost tip) to facilitate manual alignment and guidance to the connector  1  and the terminal stud  2  together. 
     A terminal stud electrical conduction portion  45  of a terminal stud  2  may comprise a terminal stud conductive surface  46 . The terminal stud conductive surface  46  may comprise an integral portion of the post  41 , for example, such as for a post  41  made of a conductive material, terminal stud conductive surface  46  may comprise an annular surface of the post  41  and arranged to rest inside the connector body  21  in contact with the connector conductive surface  22 . In various embodiments, the terminal stud electrical conduction portion  45  comprises an insert. For instance, the terminal stud conductive surface  46  may comprise an annular insert disposed over the outer circumferential surface of the post  41  and arranged to rest inside the connector body  21  in contact with the connector conductive surface  22 . 
     A terminal stud fastening portion  50  of a terminal stud  2  may comprise a fastener receiving threaded bore  51 . The fastener receiving threaded bore  51  may comprise a cylindrical channel defined by the post  41  and extending axially into the post  41 . The fastener receiving threaded bore  51  may be positioned and sized to correspond to the captive fastener  11  of the connector fastening portion  10 . The fastener receiving threaded bore  51  may be threaded to correspond to the threads of the captive fastener  11 . Thus, the fastener receiving threaded bore  51  may receive the captive fastener  11  and may be loaded in tension as the captive fastener  11  is tightened into fastener receiving threaded bore  51 , retaining the connector  1  in position relative to the stud  2 . In various embodiments, the fastener receiving threaded bore  51  is integrally formed with the stud  2 . In various embodiments, the fastener receiving threaded bore  51  comprises an insert disposed within the stud  2 . Thus, the fastener receiving threaded bore  51  may further comprise a different material than the post  41 , although in various embodiments, it is an integral feature of the post  41 . 
     A terminal stud fastening portion  50  may comprise a fastener receiving counter bore  52 . The fastener receiving counter bore  52  may comprise a bore defined by the post  41  and disposed closer to the tip than (axially outward of) the fastener receiving threaded bore  51  and co-axially aligned with the fastener receiving threaded bore  51 . The fastener receiving counter bore  52  may have a diameter greater than that of the fastener receiving threaded bore  51 . In this manner, the fastener receiving counter bore  52  may facilitate seating of the captive fastener  11  within the fastener receiving threaded bore  51  and facilitate initial threading of the captive fastener  11  into the fastener receiving threaded bore  51 . For instance, the fastener receiving counter bore  52  may facilitate guidance of a portion of the captive fastener  11  into the fastener receiving threaded bore  51 . 
     Various benefits and advantages have been described herein with regard to specific embodiments. Furthermore, the connecting lines shown in the various figures contained herein are intended to represent exemplary functional relationships and/or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in a practical system. However, the benefits, advantages, and any elements that may cause any benefit or advantage to occur or become more pronounced are not to be construed as critical, required, or essential features or elements of the disclosure. The scope of the disclosure is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” Moreover, where a phrase similar to “at least one of A, B, or C” is used in the claims, it is intended that the phrase be interpreted to mean that A alone may be present in an embodiment, B alone may be present in an embodiment, C alone may be present in an embodiment, or that any combination of the elements A, B and C may be present in a single embodiment; for example, A and B, A and C, B and C, or A and B and C. 
     The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, the following description and drawings are intended to be exemplary in nature and non-limiting. 
     Systems, methods and apparatus are provided herein. In the detailed description herein, references to “various embodiments”, “one embodiment”, “an embodiment”, “an example embodiment”, etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described. After reading the description, it will be apparent to one skilled in the relevant art(s) how to implement the disclosure in alternative embodiments. 
     Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. 112(f), unless the element is expressly recited using the phrase “means for.” As used herein, the terms “comprises”, “comprising”, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.