Abstract:
A vehicle charging system includes a base plate having an inclined surface defining at least a portion of a recess, and an arm arrangement having a base end portion movably attached to the base plate, a vehicle end portion, a spring-loaded element attached to the base end portion and in contact with the base plate, and a primary charge pad attached to the vehicle end portion. The arm arrangement has a retracted position in which at least a portion of the primary charge pad is disposed within the recess and an extended position in which the primary charge pad is spaced away from the base plate. The spring-loaded element is arranged to move along the inclined surface as the arm arrangement moves between the retracted and extended positions.

Description:
TECHNICAL FIELD 
     This disclosure relates to inductive chargers for automotive vehicle batteries. 
     BACKGROUND 
     Electric vehicles are charged with charging mechanisms. Certain charging mechanisms can include a docking station which is aligned with and connected to a corresponding vehicle port to facilitate charging. Other charging mechanism can include a charge coil that is aligned with a corresponding charge coil on a vehicle. These charge coils need not be in direct contact to facilitate charging. 
     SUMMARY 
     A vehicle charging system includes a primary charge pad, a base including an inclined surface defining at least a portion of a recess, and an arm arrangement movably attached with the base and the primary charge pad. The arm arrangement includes a spring-loaded element in contact with the base. The arm arrangement has a retracted position in which at least a portion of the primary charge pad is disposed within the recess and an extended position in which the primary charge pad is spaced away from the base. The spring-loaded element is arranged to move along the inclined surface as the arm arrangement moves between the retracted and extended positions. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view, in partial cross-section, of an inductive charging system and automotive vehicle. 
         FIG. 2  is an exploded assembly view of a portion of the inductive charging system of  FIG. 1 . 
         FIGS. 3-6  are side views, in partial cross-section, of the inductive charging system of  FIG. 1  during and after a collision with the automotive vehicle. 
         FIG. 7  is a side view, in partial cross-section, of the inductive charging system of  FIG. 1 . 
         FIG. 8  is a front view, in partial cross-section, of the portion of the inductive charging system of  FIG. 7 . 
         FIG. 9  is a bottom view of an automotive vehicle equipped with an underbody inductive charger. 
         FIG. 10  is side view of the underbody inductive charger of  FIG. 9 . 
         FIG. 11  is a front view of the underbody inductive charger of  FIG. 9  and associated charging station retracted into the ground. 
         FIGS. 12 and 13  are side views of the charging station of  FIG. 11  in retracted and extended positions respectively. 
         FIGS. 14 and 15  are side views of another charging station in retracted and extended positions respectively. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the present disclosure are described herein; however, it is to be understood that the disclosed embodiments are merely examples and other embodiments can take various and alternative forms. The figures are not necessarily to scale; some features could 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. As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures can be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations. 
       FIG. 1  is a side view, in partial cross section, of a charging station  9 . The charging station  9  is connected to a ground mount  7 . The ground mount  7  can be fashioned from any suitable material. The ground mount (base plate)  7  is a fixture in a car garage or a parking area. The ground mount  7  can be permanently fixed (not shown) directly into the ground. The ground mount  7  defines a recess  8 . The charging station  9  incorporates an arm arrangement  5  affixed to the ground mount  7  with a ball-roller  11 . The arm arrangement  5  includes an alignment arm  16  and a vertical pole  20 . 
     Further referring to  FIG. 1 , a secondary charging coil  10  may be located on a front vehicle bumper  4 . The secondary charging coil  10 , however, can be placed anywhere on the vehicle. A primary charging coil  12  is located on the charging station  9 . The primary charging coil  12  is embedded in a primary-coil pad  14 , which is connected to the arm arrangement  5 . A female end of a pivot connector  13  can be located on the primary coil pad  14 , while a male connector may be attached to the alignment arm  16 . The pivot connector  13  allows the primary-coil pad  14  to actuate circumferentially, allowing for the same charging station  9  to accommodate many vehicles of different sizes and shapes. 
     The primary coil pad  14  will also allow for more efficient coupling with the secondary charging coil  10  because the angle of the primary coil pad  14  can be moved to accommodate optimal coupling between the two charging coils. After receiving current from the primary charging coil  12 , the secondary charging coil  10  charges a vehicle battery (not shown) in a plug-in hybrid electric vehicle (PHEV) or a battery electric vehicle (BEV). 
     In the past, batteries for hybrid and photo-electric vehicles were charged using a plug-in system. These plug-in systems could have contributed to “drive off” issues in which the driver drove the vehicle while the system was plugged into a wall outlet. The charging station  9 , in  FIG. 1 , automatically decouples from the secondary charging coil  10  in the event of a “drive-off”, leaving both the charging station  9  and the vehicle unaffected. 
     The alignment arm  5  includes vertical pole  20  with a hinge connector on an elbow joint  22 . The hinge connector on the elbow joint  22  allows for the alignment arm  16  to pivot about the vertical pole  20 , adjusting for various vehicle heights and positions. 
     The vertical pole  20  is held upright by a spring mount  24  that is affixed to the ground mount  7  with spring mount pins  23 . Inside the vertical pole  20 , there is a spring rod  28  that connects to the spring mount  24 . The vertical pole  20  can be a metal rod, hollowed out on the inside. The spring rod  28 , on the top, is secured to the vertical pole  20 . 
       FIG. 2  is an exploded view of the vertical pole assembly. The vertical pole  20  is secured into the ground mount  7  with a set of round pins  26  inserted into a set of pin slots  27 . This prevents the vertical pole  20  from being removed from the ground mount  7  assembly. The ball-roller  11  rests underneath an incline slope  30 . The ball-roller  11  is attached to the spring mount  24 . The spring mount  24  secures the spring rod  28  into place. The spring rod  28  attaches to the vertical pole  20  on a spring plate  29 . The spring rod  28  attaches to the spring plate  29  with the use of the set of spring mount pins  23 . An over-center spring coil  36  is loaded onto the spring rod  28 . The spring rod  28  is also connected to the spring plate  29 . The spring plate  29  keeps the over-center spring coil  36  in a compressed state when the vertical pole  20  is in the upright position. When the over-center spring coil  36  is stretched, it is forced to compress again, and thereby the over-center spring coil  36  aids the vertical pole  20  in returning to the upright position. The ground mount  7  includes the incline slope  30  and a concavity  32 . The recess  8  is shaped to receive the vertical pole  20  and alignment arm  16 . 
       FIGS. 3-6  show the sequence as the vertical pole falls into the recess  8  after an impact with an automobile. Referring to  FIG. 3 , the ball-roller  11  is on a slider joint  34  that is located on the incline slope  30 . At the apex of the incline slope  30 , the concavity  32  is molded to hold the ball-roller  11 . The incline slope  30  is sloped for a particular tolerance. In this particular situation, it is a tolerance of 45 degrees. If a vehicle bumper  4  collides with the charging station  9 , and the collision causes the vertical pole  20  to pivot less than 45 degrees, the vertical pole  20  travels up the incline slope  30  and immediately slides down the incline slope  30 , returning to its upright position. 
     Conventional charging systems can include dock chargers. These dock chargers, however, require precise alignment for proper operation. Some drivers lack the skill required for such precise positioning. Moreover, if the driver misses the position of the charging dock and collides with the dock, the charging dock could be damaged. 
     Referring to  FIG. 6 , in an event of a collision with an automobile, the vertical pole  20  is configured to move backwards and fall into the ground mount  7  where a recess is located. During this process, the angular momentum of the vertical pole  20  can cause the alignment arm  16  to swing around and lie parallel to the vertical pole  20 . The ground mount  7  absorbs the impact of the vertical inductive charger. The automobile can then drive over of the fallen vertical pole  20  without damaging the vertical pole  20 . 
     Referring to  FIG. 4 , the vehicle bumper  4  collides with the vertical pole  20  causing the vertical pole  20  to tilt at an angle greater than 45 degrees. The ball-roller  11  travels up the incline slope  30  and falls into the concavity  32 . The ball-roller  11  does not travel back down the incline slope  30  as the concavity  32  has a hollowed shape to prevent the ball-roller  11  from rolling down the slope  30 . This also ensures that after a first collision with the charging station  9 , the vertical pole  20  does not stand back up to permit further collisions. 
     Referring to  FIG. 5 , after the vehicle bumper  4  collides with the vertical pole  20 , the alignment arm  16  pivots to a position where it is at a 180° angle with the vertical pole  20 . Furthermore, the angular momentum of the alignment arm  16  retracting towards the ground mount  7  further pushes the ball-roller  11  up the incline slope  30  and into the concavity  32 . This prevents the vertical pole  20  from sliding back down the incline slope  30 . 
     Although, a ball-roller  11  is used to move the vertical pole  20  through the incline slope  30 , the ball-roller  11  may be substituted with other mechanisms to allow for movement through the incline slope  30 . For example, a slider attached to an incline may also be used for the same function. 
     Another alternative for allowing the same functionality may be having the vertical pole  20  connected to the ground on a hinge connector which may be loaded with springs. When the springs stretch to one point, the force on the springs will push the vertical pole  20  back to the upright position. The ground behind the vertical pole could still contain the recess  8  to allow for the vertical pole to fall into it. 
     Referring to  FIG. 6 , after the ball-roller  11  is in the concavity  32 , the force on the alignment arm  16  causes the vertical pole  20  to fall into the recess  8 . The recess  8  is shaped in such a way that it absorbs the impact of the fall. If the vehicle were to drive over the vertical charger, it would be undamaged as the ground mount  7  would absorb the force. 
       FIG. 7  is a partial side view of the vertical pole  20  equipped with the spring mount  24 . The spring rod  28  is connected to the ball-roller  11  with a hinge. The over-center spring coil  36  is wrapped around the spring rod  28 . The spring rod  28  is secured in place with the spring mount pin  23 . The ball-roller  11  rests beneath the incline slope  30 . 
       FIG. 8  is a partial front view of the vertical pole  20  equipped with the spring mount  24 . The vertical pole  20  is restricted to one degree of freedom of movement with a pair of slide rails  40 . The slide rails  40  are attached to the vertical pole  20  with a hinge slot (see  FIG. 2 ). The slide rails  40  prevent the vertical pole  20  from falling in other directions. This ensures that the vertical pole  20  falls onto the recess  8 , thereby preventing the charging station  9  from being damaged in events of collisions. 
     Although in this embodiment an over-center spring coil  36  is used to keep the alignment arm  16  upright, other possible methods can be used to keep the alignment arm upright. For example, the alignment arm  16  can be connected to a slider joint using a piston. The piston can compress, sending the slider joint backwards, and may retract the height of the alignment arm. After a certain compression, the piston can also collapse allowing the alignment arm  16  to fall into the ground mount  7 . 
       FIG. 9  refers to an alternate embodiment where the system is equipped with an underbody charger. A vehicle  102  is equipped with a secondary charging coil  110 . The secondary inductive coil  110  may be located on the bottom of the vehicle  102 . 
       FIG. 10  is a side view of the car tire driving over the underbody charging station. An underbody charging station  109  (see  FIG. 11 ) is affixed to the ground. When the car tire drives over the under body charging station  109 , the under body charging station  109  retracts to be flush with the ground. The underbody charging station  109  automatically decouples from the secondary charging coil  110  in the event of a “drive-off”. 
       FIG. 11  is a front view of the underbody charging station retracted into the ground. In this particular embodiment, the vehicle  102  is currently stationed over the parking spot. The secondary inductive coil  110  may be located beneath the vehicle. When the underbody charging station  109  is in its retracted position, it is flush with the ground. The underbody charging station  109  carries a primary charging coil  112 . A primary coil pad  114  may be connected to a scissor lift  115 . The scissor lift  115  can elevate the primary charging coil  112  to many different positions. This allows for the same underbody charging station  109  to be used on many different automobiles having varying heights. The scissor lift  115  is connected to an alignment rod  116 . The alignment rod  116  has a spring coil  136  threaded on it. The spring coil  136  allows for the scissor lift  115  to move horizontally to better couple with the secondary charging coil  110 . The alignment rod  116  is connected to a ground mount  108 . The ground mount  108  secures the underbody charging station  109  into the parking spot or a car garage. 
       FIGS. 12-13  show the underbody charging station lifting up to couple with the secondary inductive coil.  FIG. 12  depicts the underbody charger in its retracted position. The scissor lift  115  is in its retracted position.  FIG. 13  depicts the under body charger  109  in its raised position. The scissor lift  115  is in its elevated position. 
       FIGS. 14-15  show an alternate embodiment for the underbody charging station.  FIG. 14  depicts an alternate embodiment of an underbody charger in its retracted position. In  FIG. 14 , a primary inductive coil  212  is located just beneath the ground on a primary coil pad  214 . The primary coil pad  214  is resting on a piston  215 . The piston  215  actuates a piston rod  216 . In this figure, the piston rod  216  is in its compressed state. The piston  215  is resting on a ground mount  208 . The ground mount  208  is secured into the ground. 
       FIG. 15  depicts another alternate underbody charger in its raised position. In  FIG. 15 , the piston rod  216  has been raised. The primary coil pad  214  contains the primary charging coil  212 . The primary inductive coil  214  has been raised to electrically couple with a secondary inductive coil  210 . 
     While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms encompassed by the claims. The words used in the specification are words of description rather than limitation, and it is understood that various changes can be made without departing from the spirit and scope of the disclosure and claims. As previously described, the features of various embodiments can be combined to form further embodiments of the invention that may not be explicitly described or illustrated. While various embodiments could have been described as providing advantages or being preferred over other embodiments or prior art implementations with respect to one or more desired characteristics, those of ordinary skill in the art recognize that one or more features or characteristics can be compromised to achieve desired overall system attributes, which depend on the specific application and implementation. These attributes can include, but are not limited to, cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. As such, embodiments described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and could be desirable for particular applications.