Abstract:
A device for a plug in vehicle includes a cord with a ball-like covering that allows it to be dropped. The cord bounces when dropped, and no damage is caused. There is also an electrical actuator that is based on when the vehicle is in a mode that allows it to be charged. When the vehicle is in the charge mode, the actuator either magnetically attracts the cord, or tightens against the cord to hold it more tightly If the vehicle is put in reverse, for example, the actuator is deenergized, and the cord is less tightly held, facilitating its disconnection.

Description:
BACKGROUND 
     A number of different kinds of electric driven or electric assisted vehicles have been suggested. Each of these vehicles use a battery that stores some kind of charge to use as power for driving the vehicle. The battery drives one or more motors that drive the vehicle. 
     A hybrid vehicle is run based on either fuel or electricity. A hybrid vehicle can either obtain charge for the battery regeneratively, such as by recovering charge from braking or from other operations in the vehicle. The battery can also be charged from electric power. A vehicle can also be purely electric, in which case the vehicle runs purely off the battery charge. 
     Vehicles that can be charged from electric power are called plug-in hybrids. These may be any of these kinds of vehicles. Such a vehicle may run solely from battery power, or may run from battery and/or fuel. 
     Typically, a plug in hybrid must be plugged in each time that it is parked. however, this means that the plug must be disconnected before the vehicle can be moved. 
     SUMMARY 
     The present application teaches mechanical structure that facilitates disconnection of a plug-in hybrid. Specifically, the structure disclosed herein may prevent damage to either the vehicle or the charging cord in the almost inevitable event that a user forgets to unplug the charging vehicle prior to use. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other aspects will now be described in detail with reference to the accompanying drawings, wherein: 
         FIG. 1  shows a basic block diagram of an electric car, and probable plug-in locations for battery charging; 
         FIG. 2  shows a socket in an embodiment; 
         FIGS. 3A and 3B  show aspects of the charging cord; 
         FIGS. 4A and 4B  show aspects of the rotatable plug; and 
         FIG. 5  shows an embodiment with movable plug blades. 
     
    
    
     DETAILED DESCRIPTION 
     A basic block diagram of an electric vehicle is shown in  FIG. 1 . The vehicle  100  includes a battery  110  that drives a motor  115  to provide power to at least one wheel  120 . In an embodiment, the vehicle may be an automobile. 
     The battery can be charged via charging system  125  that obtains power from various functions of the automobile, such as from regenerative braking, or from other kinds of movement that is otherwise wasted. The charging system  125  may be optional. In this embodiment, however, there must be an external connection for an externally applied charge for the battery. In the  FIG. 1  embodiment, the battery  110  can be charged via a plug-in connection. 
       FIG. 1  shows the many different places where a plug-in connection might be plugged into the vehicle.  130  shows a connection at the front of the car. Different connections on the side of the car include areas  131 ,  132 ,  133  on the driver side and  134 ,  135 ,  136  on the passenger side. The battery can also be charged via port  136  on the rear of the vehicle, typically the closest location to the battery  110 . The vehicle may have one or many different ports through which the power can be applied. 
     A charging cord is shown as  140 . This charging cord may simply be an AC cord carrying AC power, or may be a DC cord that carries DC power or any other type of power. 
     Depending on the position of the vehicle relative to the charging cord, it may be difficult to predict with any kind of certainty how the vehicle will be moved after charging. For example, if  FIG. 1  illustrates a garage, the vehicle may be backed up to leave the garage. Therefore, if the charging cord is plugged into port  130 , backing up will pull in more or less the direction to simply pull the plug  140  out of its socket  130 . However, if the plug is plugged into socket  134 , pulling backwards may cause damage to either the cord, or the socket on the vehicle, or both. 
     Different embodiments disclosed herein describe different ways of avoiding damage when the user forgets that the car is plugged in, and moves the vehicle without disconnecting the cord. 
     According to a first embodiment, the car-mounted socket  200  has connective electrical jack portions  205  that can be connected to the charging cord.  FIG. 2  illustrates a standard three prong jack  205 , however it should be understood that any different kind of arrangement could be used. The socket also includes a sensor block  210 . In this embodiment, the sensor block  210  is connected to the controlling processor  150  in the automobile. The sensor block  210  detects the proximity and connection of an electric cord. When the electric cord is connected, the vehicle is prevented from either starting or moving. For example, the vehicle may be allowed to start, but prevented from being taken out of “park”. A message is displayed to the user, indicating something like “vehicle immobilized, electric charging is connected.” 
     In this way, the user is prevented from driving away while the charging cord is attached. 
     The sensor  210  may be as simple as a Hall effect sensor that detects current flow, or may be a more complicated proximity sensor that detects that the proximity of the actual electric cord  140 . 
     The sensor  210  may also carry out other functions as described herein with reference to other embodiments. 
     The socket assembly may also include an electrically actuable magnet  220  that positioned and usable to attract the plug that is close to the magnet.  FIG. 2  shows a rectangular magnet. Alternatively, the magnet  220  may be arcuate in shape. 
       FIGS. 3A-3B  illustrate an electric cord that can be plugged into the socket shown in  FIG. 2 . In an embodiment, the electric cord  300  may be a conventional AC electric cord with a first end  305  that is adapted to be plugged into a conventional wall mounted electric outlet, and a second end  310  that plugs into the Jack  205  shown in  FIG. 2 . In the embodiment, the second end  310  includes a plug portion  315  which includes electrical prongs such as  316  that connect to corresponding electric prongs  201  of the Jack  205 . The plug portion  315  also includes a metal or magnet portion  318  positioned to magnetically interact with the corresponding magnet portion  220  of the Jack  200 . The magnet portion may be substantially circular, extending circumferentially around the outside of the plug, or may be in one location only. 
     Damage might occur when the plug is pulled out of the vehicle very quickly, for example by accident when the user pulls away while the plug is plugged in. If that happens, the plug could bang against a hard garage floor or the like. This could break or otherwise damaged the plug. In this embodiment, the second end  310  is surrounded by a protective sheath  320 . The protective sheath  320  may be a section of a sphere, for example a elastomeric, e.g., rubber partial sphere that is connected by connection structures  325  to the plug portion  315 . For example, the sheath  320  may be like a cut-open tennis ball that is connected to both the cord and to the plug portion. The sphere  320  is open at section  322  so that the plug  315  can be attached to the jack  205 . However, if the plug  315  is dropped, then the sphere  320  will effectively bounce on the floor, and will not be damaged by hitting the floor even from a great height. Therefore, the cord can be pulled out of the automobile when the automobile is driven while being plugged in. The cord will fall, but bounce on the sphere portion. No damage will occur even if the automobile is driven away while plugged in. 
       FIG. 3B  illustrates a front on view of the structure, showing a cross-sectional view of the sphere  320 , the plug  315 , and also showing how the opening  322  allows access to the plug  315 . Since the ball diameter gets progressively larger,  FIG. 3B  shows the largest point  355  of the open sphere  320 . 
     An additional embodiment may include an actuator  360 . In the embodiment, the jack  205  includes blades such as  201 . The mating plug portion  315  therefore includes a female connection which fits around the blades  201 . One way of facilitating the disconnection is that the female connection tightens and loosens around the blades  201 . In the normal, unactuated condition, the female connection is loose around the blades  201 . However, this loose connection would not facilitate a good electrical connection between the female connection  315  and the male blades  201 . Therefore, an embodiment has an actuator  360  which selectively tightens the connection of the female portion  315  around the male portion  201 . For example, the female portion  315  may include electrical contacts that are spaced from one another by a distance that is larger than an outer size of the blade  201 . The actuator moves those contacts closer together, to grip the blade  201 . The actuator  360  may be controlled by a magnetically actuated switch  366 , that is closed by the actuation of the electromagnet  220 . The electromagnet  220  is actuated only when the vehicle is in a mode where it can be charged. 
     In an embodiment, it is contemplated that the female portion would be on the electric cord that connects to the automobile, and that the automobile would have the male portion. However, these may be reversed, in which case the actuator would actually be on the plug shown in  FIG. 2 . The actuator  360  may be, for example, a piezoelectric device which selectively tightens the metal contacts within the female connection against the corresponding blades in the male connection. 
     The actuator  360  requires power, and accordingly this may be powered by the actual electricity supplied over the plug  300 . In the embodiment, sensing by the sensor  210 , or other proximity sensor, may be used to actuate the actuator  360  to selectively tighten against the plug. 
     Also in an embodiment, the plug is held to the jack any time the car is properly in a condition in which it can be charged, such as when the car is in park, or the ignition key is off, or whatever other condition indicates that the vehicle can be charged by a plug in plug. This condition may be detected by any vehicle mounted device, e.g., the controlling processor  150 , or any other circuit, or a mechanical interlock. The holding can be maintained by the actuator  360  tightly held against the male blades, or the electromagnet  220  holding the corresponding metal portion  318 . 
     However, when the car is removed from park, the processor  150  operates to release the holding. At this point, the plug is loosely fitted on its corresponding portion in the actuator embodiment, and can be removed very easily. In the magnetic attraction embodiment, the magnetic connection is released. 
     In another embodiment, there may be a disconnect control shown as  370 , either on the outside of the protective sphere  320 , or located anywhere else on the cord. The disconnect control causes the actuator  360  to disconnect, thereby allowing easy removal of the plug from the corresponding jack. Either way, however, if the car is improperly moved, the actuator is disconnected, causing the blades to be removed from the plug. 
     In another embodiment, it is noted that the plug assembly  140  may actually be connected into the vehicle from an angle that prevents easy plug release when the vehicle backs up. For example, if the plug  140  is connected into section  134 , damage could occur if the vehicle goes straight backwards. The embodiment of  FIG. 4A-4B  may address this. 
     In the  FIG. 4A  embodiment, the car-mounted socket  400 , here shown as a male plug, includes a ball that is pivotable in both of pan and tilt directions. This is done by attaching the plug assembly  400  to a support section  405  that is shaped in the shape of a portion of a sphere. This arc of the sphere is mounted within, and maintained as a captive within, a second spherical supporting section  410 . The plug holding spherical section  405  is movable within the supporting section  410 . Therefore, as shown in  FIG. 4A , the plug can move in the up-and-down direction, in side to side directions, and can move to any angle in both those directions, limited only by the mechanical stops of the system. 
     In an embodiment, the plug  400  is fed by a coiled cord  420  which can be moved to a plurality of different positions. The supporting section  410  includes an opening  411  through which coiled cord  420  extends. The opening only has a certain size, and the position of the cord on the support section  405  limits the range of possible movement of the plug holding support section  405 . 
     In this way, any angle that the vehicle may assume relative to the Jack can be supported by the rotational movement of the support section. 
       FIG. 5  illustrates yet another embodiment which can be usable with any of the embodiments disclosed previously. In this embodiment, the conductive blade  500  which receives the power from the charging cord is controlled by an actuator  505 . The actuator  505  controls movement of the blade in the inward and outward directions, so that the blade can retract responsive to the control signal  510 . The control signal may be sent by a user putting the vehicle into drive from park. A signal is sent which quickly retract the cord blades, thereby quickly removing contact and connection between the supplying power cord and the jack. The cord may then fall to the floor, but preferably uses the embodiment of  FIG. 3 , so that it will not be damaged. 
     The actuator  505  may also provide some expansion of the blade, to cause it to fit more snugly into the Jack. In addition, actuator  505  can be used in conjunction with the actuator  360  shown in  FIG. 3B , so that both actuators can simultaneously engage and disengage, thereby more quickly removing the connection. 
     Although only a few embodiments have been disclosed in detail above, other embodiments are possible and the inventors intend these to be encompassed within this specification. The specification describes specific examples to accomplish a more general goal that may be accomplished in another way. This disclosure is intended to be exemplary, and the claims are intended to cover any modification or alternative which might be predictable to a person having ordinary skill in the art. For example, the “sexes” of the car mounted socket/plug and the cord may be easily reversed, and any of the structures discussed herein may be interchanged between car mounted part, and cord mounted part. 
     Also, the inventors intend that only those claims which use the words “means for” are intended to be interpreted under 35 USC 112, sixth paragraph. Moreover, no limitations from the specification are intended to be read into any claims, unless those limitations are expressly included in the claims. 
     The automobile controllers described herein may be any kind of computer, either general purpose, or some specific purpose computer such as a workstation. The processor may be a Pentium class computer, running Windows XP or Linux, or may be a Macintosh computer. The controller may also be a handheld computer, such as a PDA, cellphone, or laptop. 
     The programs may be written in C, or Java, Brew or any other programming language. The programs may be resident on a storage medium, e.g., magnetic or optical, e.g. the computer hard drive, a removable disk or media such as a memory stick or SD media, or other removable medium. The programs may also be run over a network, for example, with a server or other machine sending signals to the local machine, which allows the local machine to carry out the operations described herein. 
     Where a specific numerical value is mentioned herein, it should be considered that the value may be increased or decreased by 20%, while still staying within the teachings of the present application, unless some different range is specifically mentioned.