Abstract:
A connector assembly is provided with a support structure having an elongate shape and an inlet for receiving a charging cable. A fitting is disposed in mechanical interlocking engagement with a distal end of the support structure for interconnecting the support structure with a vehicle charging receptacle. The support structure and the fitting are configured for disconnecting from each other when the connector assembly is subjected to a lateral load above a predetermined threshold value.

Description:
[0001]    This application is a continuation of U.S. application Ser. No. 12/829,490 filed Jul. 2, 2010, the disclosure of which is incorporated in its entirety by reference herein. 
     
    
     TECHNICAL FIELD 
       [0002]    One or more embodiments relate to a connector assembly for facilitating the electrical charging of a vehicle. 
       BACKGROUND 
       [0003]    Electric vehicles and many hybrid vehicles include a receptacle that is electrically connected to a vehicle battery. The receptacle receives an electrical connector that is coupled to a power supply for charging the vehicle battery. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]      FIG. 1  is a schematic view of a connector assembly for electric vehicle charging according to at least one embodiment of the present invention; 
           [0005]      FIG. 2  is a side perspective view of the connector assembly of  FIG. 1 , illustrated partially disassembled; 
           [0006]      FIG. 3  is a side perspective view of the connector assembly of  FIG. 2 , illustrated further disassembled; 
           [0007]      FIG. 4  is an enlarged partial section view of the connector assembly of  FIG. 2  taken along section line  4 - 4 ; 
           [0008]      FIG. 5  is an exploded side perspective view of the connector assembly of  FIG. 2 ; 
           [0009]      FIG. 6  is a rear perspective view of a plug of the connector assembly of  FIG. 2 ; 
           [0010]      FIG. 7  is a top view of the connector assembly of  FIG. 2 , illustrated in an unloaded position; 
           [0011]      FIG. 8  is another top view of the connector assembly of  FIG. 2 , illustrated in a loaded position; and 
           [0012]      FIG. 9  is yet another top view of the connector assembly of  FIG. 2 , illustrated in another loaded position. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. 
         [0014]    With reference to  FIG. 1 , a connector assembly for facilitating the electric charging of a vehicle is illustrated in accordance with an embodiment and is generally referenced by numeral  10 . In general, a connector assembly having a break-away feature is provided for releasably coupling an electrical power supply to a “plug-in” electric or hybrid vehicle. 
         [0015]    The connector assembly  10  is coupled to a charging cable  12  and a power supply  14  for transferring electrical power. The connector assembly  10  is attached to the end of a charging cable  12 . The charging cable  12  extends from the power supply  14 . The power supply  14  represents an AC electrical power supply, such as a standard residential power circuit. 
         [0016]    A “plug-in” electric or hybrid vehicle  16  is coupled to the power supply  14  for electrical charging. The vehicle  16  includes a vehicle charging receptacle  18  and a battery  20  for receiving electrical power. The vehicle charging receptacle  18  is mounted to be externally accessible from the vehicle  16 . The vehicle charging receptacle  18  receives the connector assembly  10 . The battery  20  is electrically connected to the charging receptacle  18  for storing electrical power. The vehicle  16  or the power supply  14  may also include a converter (not shown) for converting AC to DC electrical power for storage in the battery  20 . 
         [0017]      FIG. 1  depicts the vehicle  16  driving away from the power supply  14 . Once the vehicle  16  has traveled far enough to remove any slack within the charging cable  12 , tensile forces develop within the charging cable, which result in a transverse load  22  acting upon an intermediate portion of the connector assembly  10 . This “drive away” event is provided for illustrative purposes, however other situations could result in such a transverse load  22  applied to the connector assembly  10 . For example an individual could inadvertently walk into the assembly  10 , or drop a heavy object on the assembly  10 , while it is connected. 
         [0018]      FIG. 2  illustrates the connector assembly  10  of  FIG. 1 , without an outer shell  24 . The outer shell  24  helps retain and enclose the components of the connector assembly  10 . 
         [0019]    The connector assembly  10  includes an elongate handle  26  and a plug  28  connected to each other for facilitating electrical charging of the vehicle  16 . The connector assembly  10  includes a break-away feature  30  whereby the handle  26  disconnects from the plug  28  when the assembly  10  is subjected to a predetermined transverse load  22 . By localizing damage to the connector assembly  10 , the break-away feature  30  also minimizes damage to the vehicle  16  and the power supply  14  during transverse loading. Typically, damage to the vehicle  16  or power supply  14  is more expensive to repair, than damage to the connector assembly  10 . 
         [0020]    The handle  26  includes an inlet  32  for receiving the charging cable  12 . The inlet  32  is formed at a proximal end of the handle  26 , away from the plug  28 . The charging cable  12  may include a flexible grommet  34  attached to an end of the cable  12  for providing strain relief and a seal between the cable  12  and the inlet  32 . 
         [0021]    The plug  28  engages the vehicle charging receptacle  18 . An interface between the plug  28  and the vehicle charging receptacle  18  may be specified in an effort to standardize the connection throughout the electric vehicle industry. For example the Society of Automotive Engineers (“SAE”) has specified such an interface in SAE-J1772, which is hereby incorporated by reference. However the connector assembly  10  is not limited by this SAE specification and may be utilized for applications specifying other interface requirements. 
         [0022]    The connector assembly  10  includes a latching mechanism  36  for attaching the connector assembly  10  to the charging receptacle  18 . The latching mechanism  36  is designed to maintain the electrical connection to the vehicle  16  while charging the battery  20 . The latching mechanism  36  also prevents the connector assembly  10  from simply disconnecting from the vehicle  16  when a load is applied to the connector assembly  10 . 
         [0023]    The latching mechanism  36  includes a lever  38 , a link  40  and a trigger  42  coupled to one another. The lever  38  is pivotally coupled to an upper portion of the handle  26 . The link  40  is pivotally coupled to an intermediate portion of the handle  26 . The link  40  is coupled to the lever  38  and pivots in an opposite direction as the lever  38 . A lip  41  extends along an upper periphery of the trigger  42  for engaging the link  40 . A compression spring  43  is provided for biasing the lever  38  in a latched position (as illustrated in  FIG. 2 ). The spring  43  is located between a distal portion of the lever  38  and an upper portion of the handle  26 . 
         [0024]    By pulling the trigger  42  toward the handle  26 , the lip  41  pivots the link  40  counter-clockwise, which in turn pivots the lever  38  clockwise and away from the plug  28 . As the lever  38  pivots clockwise, it compresses the spring  43  and unlatches the connector assembly  10  from the vehicle receptacle  18 . Once the trigger  42  is released, the spring  43  pivots the lever  38  back into the latched position. Thus the latching mechanism  36  allows a user to selectively attach the connector assembly  10  to the vehicle charging receptacle  18 . 
         [0025]    With reference to  FIG. 3 , the elongate handle  26  includes the inlet  32 , an outlet  44  and a body  46  formed between the inlet  32  and outlet  44 . 
         [0026]    The body  46  forms a longitudinal internal cavity  48  for supporting the charging cable  12 . The charging cable  12  includes a sheathing  50  formed around an electrical harness  52 . The sheathing  50  insulates and protects the harness  52  along the length of the cable  12  outside of the connector assembly  10 . The sheathing  50  ends at the inlet  32  of the handle  26  and the harness  52  extends along the internal cavity  48 . The portion of the harness  52  located within the cavity  48  is encapsulated by a molded material  54  which is formed by a low-pressure molding process. In one embodiment the molded material  54  includes Macromelt® material by Henkel Corporation of Madison Heights, Michigan. The molded material  54  helps insulate and seal the harness  52 . Additional electronic components, such as a position sensor  56  and LED  58  may also be encapsulated within the body  46  by the molded material  54 . 
         [0027]    Referring to  FIGS. 3 and 4 , the outlet  44  of the handle  26  forms a generally cylindrical pocket  60  that is longitudinally recessed toward the body  46 . The pocket  60  encloses a free-length portion  62  of the electrical harness  52 . For brevity, only one free-length portion  62  is illustrated in  FIG. 4 . A female wire terminal  64  is attached or soldered to the end of each free-length portion  62 , and secured within the plug  28 . The pocket  60  does not include any molded material  54 , therefore the free-length portion  62  of the harness  52  is allowed some flexibility in movement. 
         [0028]    The outlet  44  includes a series of slots  66  for attaching the handle  26  and the plug  28  to each other. The slots  66  are formed through an external wall  68  of the pocket  60 . The illustrated embodiment includes an outlet  44  with three equally dimensioned slots  66 , such that each slot  66  has a common length and width. Additionally, each slot  66  is equally spaced about a circumference of the outlet  44  at 120 degrees intervals. However, other embodiments of the connector assembly  10  contemplate more than three slots  66 ; slots  66  having differing dimensions with respect to one another; and irregular spacing between adjacent slots  66 . 
         [0029]    With reference to  FIGS. 4-6 , the handle  26  may be formed by a clamshell structure with a front portion  70  and a rear portion  72  attached to one another by transverse fasteners. Additionally an adhesive or gasket may be applied to an outer periphery of each portion  70  and  72  to seal the internal cavity  48 . 
         [0030]    The plug  28  includes a terminal cover  74 , a wiper seal  76  and a shroud  78  coupled to one another for sealing the plug  28 . The terminal cover  74  includes a disc-shaped base  79  with a first side surface  80  and a second side surface  82 . The first side surface  80  is oriented adjacent to the outlet  44  of the handle  26  and opposite the second side surface  82 . A ring  84  is formed along a circumference of the base  79  and longitudinally extends in opposing directions. The outer diameter of the ring  84  is stepped such that the portion of the ring that extends beyond the second side surface  82  has a smaller outer diameter that the portion of the ring  84  that extends beyond the first side surface  80 . The wiper seal  76  is generally cylindrically shaped and positioned to abut the ring  84  adjacent to the second side surface  82 . 
         [0031]    The shroud  78  attaches to the terminal cover  74  to retain the seal  76 . The shroud  78  is tubular and generally cylindrically shaped. The shroud  78  includes a recess  86  for receiving the stepped outer diameter of the cover  74 . The recess  86  is formed along a proximal end of the inner diameter of the shroud  78  at a proximal end of the plug  28 . The shroud  78  also includes a groove  88  formed along an intermediate portion of the inner diameter which extends to the recess  86 . The groove  88  and the ring  84  collectively form a radial channel  90  for longitudinally retaining the seal  76  within the plug  28 . In one embodiment the terminal cover  74  and shroud  78  are attached to each other by an ultrasonic weld at the interface between the recess  86  and the ring  84 . 
         [0032]    The terminal cover  74  secures the female terminals  64 . A series of cylindrical terminal receptacles  92  extend transversely from the second side surface  82  of the plug  28 . Each terminal receptacle  92  forms a terminal cavity  94  for receiving a female terminal  64 . The connector assembly  10  may also include a back plate  96  that attaches to the first side surface  80  of the terminal cover  74  for retaining the female terminals  64 , each within a terminal cavity  94 . The illustrated embodiment of the connector assembly  10  depicts a five-terminal plug  28  that is designed according to the interface requirements of the SAE-J1772 specification. 
         [0033]    The terminal cover  74  also includes a series of tabs  98  for attaching the plug  28  to the handle  26 . The series of tabs  98  longitudinally extend from a peripheral edge of the base  79 . The tabs  98  are aligned with the slots  66  and received into the pocket  60  of the handle  26 . Each tab  98  is formed with a longitudinal length, a lateral curved width and a thickness. A transverse projection  100  is formed along the width of each tab  98 . Each projection  100  extends radially outward from an intermediate portion of the length of the tab  98 . 
         [0034]    The projections  100  are sized for engaging a corresponding slot  66  with an interference fit. An interference fit ensures line contact at opposing sides of the slot  66  to distribute applied loads. As illustrated in  FIG. 4 , the projections  100  are formed with a rounded profile. In one embodiment, the projections  100  are formed with a two millimeter radius and the slots  66  are formed with a width less than four millimeters, for providing an interference fit. 
         [0035]    Referring to  FIG. 6 , the illustrated embodiment includes three tabs  98 , where each tab  98  is equally spaced about the circumference of the base  79 . The tabs  98  may be spaced at 120 degree intervals, with one tab  98  oriented in a lower “6-o&#39;clock” position. However, other embodiments of the connector assembly  10  contemplate more than three tabs  98 ; tabs  98  having differing dimensions with respect to one another; and irregular spacing between adjacent tabs  98 . 
         [0036]      FIGS. 7-9  illustrate the break-away feature  30  of the connector assembly  10 . The tabs  98  and the slots  66  are configured to provide a structural weak point for failure when the connector assembly  10  is subjected to a predetermined transverse load  22  applied to an intermediate portion of the assembly  10 . The tabs  98  and slots  66  are designed to “fail” such that the handle  26  disconnects from the plug  28 . Such failure may be achieved by plastic or elastic deformation of at least one of the tabs  98  and or the slots  66 . In one embodiment the connector assembly  10  is configured as a frangible connector assembly  10  where the tabs  98  are configured to fracture when the assembly  10  is subjected to the predetermined load  22 . Additionally,  FIGS. 7-9 , represent loading on the connector assembly  10  when the plug  28  is constrained by the charging receptacle  18  (illustrated in phantom). 
         [0037]      FIG. 7  illustrates a top view of the connector assembly  10  in a connected and unloaded position. The handle  26  is connected to the plug  28  and each projection  100  is fully engaged with the corresponding slot  66 . Additionally, the free-length portion of the harness (not shown) is partially compressed and flexible. 
         [0038]      FIG. 8  illustrates a top view of the connector assembly  10  in a partially connected and loaded position. The transverse load  22  is applied to an intermediate portion of the handle  26 . The tabs  98  elastically deform in the direction of the load  22 , and the handle  26  pivots counterclockwise. Although the tabs  98  are deformed, the projections  100  still engage the slots  66 . 
         [0039]      FIG. 9  illustrates the connector assembly  10  in a disconnected and loaded position. As the tabs  98  deform beyond the positions illustrated in  FIG. 8 , the projections  100  disengage from the slots  66 , and the handle  26  disconnects from the plug  28 .  FIG. 9  depicts an upper tab  98  that has elastically deformed and has returned to its original position, and a lower tab that has plastically deformed and fractured. Additionally, the free-length portion  62  of the harness has extended to allow the projections  100  to fully disengage the slots  66  for facilitating disconnection of the handle  26 . 
         [0040]    The break-away feature  30  may be designed to withstand a predetermined transverse load  22  applied to the connector assembly  10  before the handle  26  disconnects. The performance of the break-away feature  30  may be adjusted to accommodate different loading requirements by adjusting dimensions and material properties of the tabs  98  and slots  66 . 
         [0041]    For example, in one embodiment the connector assembly  10  is configured to break-away or fail when a transverse load between 160-300 Newtons is applied to an intermediate portion of the connector assembly  10 . A minimum load requirement is necessary to prevent the connector assembly from failing during normal operating conditions. A maximum load requirement prevents damage being sustained by the power supply  14  or vehicle  16  during loading. To accommodate the 160-300 Newton load requirement, both the handle  26  and tabs  98  are molded from a nylon material such as Ultramid®, a Polyamide 6/6 from BASF of Wyandotte, Mich. Additionally, the tabs  98  are designed to have common dimensions with a thickness between 2-3 mm. Other embodiments of the connector assembly  10  contemplate the handle  26  and the tabs  98  being formed from other polymers such as polypropylene or acetal. 
         [0042]    While embodiments of the invention are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.