Abstract:
An apparatus for supplying an electrical charge to a vehicle having a plurality of contact members and a plurality of elastic members secured to the inner surface of the plurality of contact members at one end and a plurality of relays at the other end. The relays are suspended behind the inner surface of the plurality of contact members and the elastic members allow the plurality of relays to travel in a range defined by a first position and a second position and the relays are in a facially spaced relationship with the inner surface of the contact members when the relay is in the first position and the relays make contact with the inner surface of the contact members when the relay is the second position and a power conduit connects the plurality of relays to an electrical supply.

Description:
TECHNICAL FIELD 
     The present invention relates to hybrid and electric vehicles. In particular, an apparatus for providing a source of current for recharging is disclosed. 
     BACKGROUND OF THE INVENTION 
     Electric vehicles have been available for many years. However, and due to certain limitations, the use of electric vehicles has been mainly in special applications. Recently, due to environmental considerations, as well as technological developments and advancements in the area of batteries, electric vehicles are gaining wider acceptance. In addition, and in certain regions of poor air quality, legislation has been adopted requiring that a percentage of new vehicles in these areas be electrically powered. 
     Electric vehicles have a number of advantages, including high efficiency, zero emissions, as well as being much quieter. The biggest drawback of an electric vehicle is that ultimately it must be recharged and accordingly it has a limited range. For many drivers, the range of an electric vehicle is sufficient and the vehicle&#39;s batteries can be recharged at the driver&#39;s residence or at a service location over night before the vehicle is driven again. 
     In addition, and due to technological advances in automotive designs as well as battery powered vehicles, hybrid vehicles with much greater ranges are being introduced. A Hybrid Vehicle is a vehicle that has at least two sources of energy. A hybrid electric vehicle (HEV) is a vehicle wherein one of the sources of energy is electric and the other source of energy may be derived from a heat engine that burns diesel, gasoline or any other source of chemical energy. Accordingly, a hybrid electric vehicle may have a much greater range before its batteries need recharging. Moreover, these vehicles are also equipped with a means for charging the batteries through their onboard internal combustion engines. 
     One contemplated means for recharging an electric or hybrid vehicle is an electric vehicle charging station wherein single plug devices having a system for metering time or power for billing the customer are used. These systems are expensive to install as well as operate. Another problem with current methods of charging electrical vehicles at charging stations is that the connector cables connecting the charging device to the vehicle are often exposed and difficult to handle. 
     A further problem with charging stations is that plug-in locations are often outdoors, exposed to the elements. Weather conditions, such as rain or snow, can impede the proper and safe operation of such electrical systems, which operate at high power levels. 
     The buildings or housings associated with conventional charging stations are constructed in a manner such that they are not convenient to install and to relocate in the event a change of location becomes necessary. The cost to build these structures, which are generally permanent structures, is high and most contemporary charging stations are single function units providing only charging services. 
     Accordingly, there is a need for a quick and convenient means for providing a source of electricity to re-charge an electrically powered automobile. 
     SUMMARY OF THE INVENTION 
     In an exemplary embodiment, a charging system provides a quick and efficient means for an operator to connect their vehicle to an electrical supply source in order to recharge their electric or hybrid electric vehicle. The charging system can be utilized at home and the vehicle operator does not have to manually connect the vehicle to a source of electric power. The operator simply positions their vehicle over the charging system of the instant application. There is no requirement for special connections or adaptations. 
     In addition, the system is configured for use with a common household 120 volt AC supply. 
     The above-described and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description, drawings, and appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a top plan view of a charging mat constructed in accordance with the instant application; 
     FIG. 2 is a diagrammatic view of portions of the apparatus of the instant application; 
     FIG. 3 is a perspective view of component parts of the apparatus of the instant application; 
     FIG. 4 is a perspective view of component parts of the apparatus of the instant application; 
     FIG. 5 is a perspective view of component parts of the apparatus of the instant application; 
     FIG. 6 is a cross-section of view along lines  6 — 6  of FIG. 1; 
     FIG. 7 is a perspective view of component parts of the apparatus of the instant application; 
     FIG. 8 is a perspective view of the lower portion of a charging mat of the instant application; 
     FIG. 9 is a perspective view of component parts of the apparatus of the instant application; 
     FIG. 10 is a side elevation of view illustrating operation of the instant application; 
     FIG. 11 is a cross-sectional view illustrating operation of the instant application; and 
     FIG. 12 is a flowchart illustrating portions of a command sequence for the charging system of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, a charge mat  10  constructed in accordance with the present invention is illustrated. Charge mat  10  has a mat  12  that is constructed out of a durable rubber compound capable of withstanding the pressure on an accidental drive over by a vehicle operator. In addition, mat  12  is also nonconductive to electricity and is able to conform to slight variations in the surface over which it is placed. 
     In an exemplary embodiment, mat  12  is rectangular shaped and has the following dimensions, 100 cm×80 cm. Of course, and as applications may require, these dimensions may vary. Charge mat  12  is also beveled along its periphery. This also prevents damage to mat  12  by accidental drive overs and, in addition, will reduce the likelihood of an individual tripping over mat  12 . 
     Mat  12  also includes a pair of relay fields  14  and  16  (illustrated by the dashed lines in FIG.  1 ). In an exemplary embodiment, fields  14  and  16  have the following dimensions, 40 cm×50 cm. Of course, and as applications may require, these dimensions may vary. In accordance with the instant application, one of the relay fields performs the function of electrical grounding while the other supplies household AC power. 
     Referring now to FIG. 2, fields  14  and  16  each have a plurality of highly magnetic permeable slugs  18  (FIG.  3 ). In an exemplary embodiment, slugs  18  are iron. Of course, other materials being magnetically permeable and having conductive qualities may be used for slugs  18 . Referring back now to FIG. 1, mat  12  has a plurality of openings  20 . Openings  20  are positioned to lie within fields  14  and  16 . A plurality of contact caps  22  (FIG. 4) are inserted into openings  20  through the underside of mat  12 . In an exemplary embodiment, contact caps  22  are constructed out of magnetic stainless steel. 
     Referring now to FIGS. 3-6, slugs  18  are configured to have a channel  24  disposed about the periphery of slugs  18 . Channel  24  is configured to receive an elastomeric spring  26  (FIG.  5 ). 
     Each opening  20  is configured to tapered wall portion  28  and a receiving area  30  (FIG.  6 ). Each cap  22  is configured to have an engagement surface  32 , an inclined portion  34 , a securement portion  36  and a receiving area  38  (FIG.  4 ). 
     Referring now to FIG. 6, contact caps  22  are inserted into openings  20 . The configuration of contact caps  22  allows engagement surface  32  and a portion of inclined surface  34  to extend out through opening  20 . Securement portion  36  is engaged and received within receiving area  30 , and the remaining portion of inclined surface  34  that does not extend through opening  20  makes contact with tapered wall portion  28  of opening  20 . In an exemplary embodiment, contact caps  22  are inserted into openings  20  and a retaining portion  39  is filled and behind contact cap  22 . Retaining portion  39  secures contact cap  22  in position. 
     As an alternative, retaining portion  39  is inserted and placed behind contact cap  22 . Retaining portion  39  can be configured to have a snap fit with mat  12 . Alternatively, retaining portion  39  may be secured to mat  12  with an adhesive. In yet another alternative, retaining portion  39  may be configured to be part of mat  12  and flexible enough to allow for the insertion of contact cap  22  within opening  20 . In addition, contact caps  22  may also be flexible enough to allow for the securement of contact caps  22  within opening  20 . 
     Each Elastomeric spring  26  has an inner opening  40  which is sufficiently large enough to allow the bottom portion of slugs  18  to pass through (FIG.  5 ). Elastomeric spring  26  is engaged within channel  24  of slugs  18 . As slugs  18  are inserted into contact caps  22 , the outer periphery of elastomeric spring  26  is engaged within receiving area  38  of contact caps  22 . 
     In this configuration, slugs  18  are suspended beneath contact caps  22  and an insulating airgap  42  is maintained between slugs  18  and contact caps  22 . Each slug is configured to have a wire  44  connected to a slug terminal  46 . Wire  44  connects slug  18  to either an AC power supply or an electrical ground depending upon which relay field slug  18  is positioned in. 
     FIGS. 7-9 illustrate the top and bottom of charge mat  12  including openings  20  and a perspective view of slug  18  inserted into opening  20 . 
     Referring now to FIG. 10, as a vehicle (not shown) drives over charge mat  12 , a pair of contact pads  48  descend downwardly from the vehicle and make contact with at least one contact cap  20  of each field. In an exemplary embodiment, contact pads  48  are configured and dimensioned to have a surface area large enough to make contact with at least one or a maximum of four contact caps of each field. This allows contact pads  48  to make contact with at least one contact cap regardless of the positioning of the contact pad with respect to charge mat  12 . In an exemplary embodiment, the dimensions of contact pads  48  are 100 mm×120 mm. Of course, and as applications may require, pads  48  can be configured to make contact with a lesser or larger amount of caps  22  as long as pads  48  still make contact with at least one contact cap. 
     Referring now to FIGS. 10 and 11, each contact pad  48  has an electromagnet  50  positioned on the lower surface of contact pads  48 . Once the electromagnets make contact with contact caps  20 , the electromagnets activate and generate a magnetic force which will draw slug relays  18  towards contact cap  20  so that a portion of relay slug  18  makes contact with contact cap  20 . In this configuration charge mat  10  is now ready to supply an electrical charge to the contact pads of a vehicle. 
     Referring back now to FIGS. 1 and 2, field  14  is connected to an AC current supply through a power cord  52 . Power cord  52  has an AC supply line  54  and a ground line  56 . AC supply line  54  is connected to field  14  and ground line  56  is connected to field  16 . A relay  58  connects supply line  54  to field  14 . In addition, and as an alternative, an optional relay  60  can be positioned along ground line  56  to connect ground line  56  to field  16 . The incorporation of an optional relay will prevent field  16  from being electrically charged through the inadvertent reverse polarity connection of power cord  52  into an electrical outlet. In an exemplary embodiment, power cord  52  is configured to be plugged into a typical North American AC outlet supplying  110 - 120 . Of course, and as applications vary, power cord  52  and charge mat  10  can be configured to accept higher or even lower voltage electrical sources. Moreover, and in international applications, charge mat  10  and power cord  52  can be configured to accommodate variations in electrical supply systems. 
     A radio frequency communications module  62  is connected to supply line  54  and ground line  56 . In addition, module  62  is configured to supply relays  58  and  60  with commands which will connect their respective lines to their respective fields. 
     Accordingly, and as the charging pads descend from a vehicle, the vehicle sends out a radio frequency signal to connect relays  58  and  60  after the charging pads have descended and made contact with at least one charging cap  22  to each field. Once the signal is received by module  62 , the module instructs relays  58  and  60  to close, and thus charging commences. 
     After the vehicle charging is complete, the vehicle sends out a radio frequency signal to instruct module  62  to disconnect relays  58  and  60 . Accordingly, and through the use of module  62  and relays  58  and  60 , no electrical power is supplied to charge mat  10  until the contact pads of a vehicle are in place. In addition, the contact pads of the vehicle draw the relay slugs upwardly until a portion of the relay slug makes contact with the contact cap prior to the supply of an electrical current to the slugs. The process of drawing up the relay slugs and the contact of the contact pads to the contact cap prior to the connection of an electrical supply to charge mat  10  prevents any arcing at the point of contact. This will prevent damage to contact caps  22  and relay slugs  18 . 
     Referring now to FIG. 12, a pair of flowcharts  70  illustrates portions of a command sequence for the charge mat operation protocol. The flow charts illustrate the command sequence and operation protocol for the vehicle and the charge mat. In an exemplary embodiment, a computer algorithm resident upon a microprocessor within the vehicle will perform portions of the command sequence illustrated in FIG.  12 . Communications module  62  in response to commands from the vehicle interface system also performs portions of the command sequence illustrated in FIG.  12 . 
     As an alternative, a computer algorithm and a microprocessor may also be located within communications module  62  in order to perform portions of the command sequence illustrated in FIG.  12 . 
     Communications module  62  of charge mat  10  sends out a signal A which searches for a vehicle interface system. Signal A is preferably sent out in five second intervals. Of course, this time limit or parameter may vary. Once a vehicle operator has positioned the front end of their vehicle over charge mat  10  and the operator places the vehicle in “Park” mode, the vehicle interface system will receive signal A from charge mat  10 . This is designated by a step  72  in flowcharts  70 . 
     Once a signal has been received by the vehicle interface system, a decision node  74  evaluates the vehicle&#39;s charge condition and determines whether a charge is necessary. If so, step  76  instructs contact pads  48  to be lowered until electromagnets  50  make contact with at least one contact cap  20  of each field. Once contact has been made, a step  78  engages the electromagnets of the vehicle interface system and the magnetic field at contact pad  48  will draw local relay slugs  18  upward until a portion of slugs  18  makes contact with contact cap  22 . 
     Once this has been accomplished, a step  80  instructs the vehicle interface system to send out an enable AC signal (signal B). Signal B is received by communications module  62  of charge mat  10 , and communication module  62  instructs relay  58  and, if installed, relay  60  to close, effectively completing the circuit of charge mat  10  wherein electrical power is now supplied to the vehicle interface system. This is accomplished by a step  81 . 
     Within the vehicle interface system, a decision node  82  determines whether the charging sequence is complete. This is accomplished by accessing the current state charge of the vehicle&#39;s battery system. If the charge is complete, a step  84  sends out a charge complete signal (signal C). Signal C is received by communications module  62  of charge mat  10  and relays  58  and  60  are opened. This is illustrated by a step  85 . Once relays  58  and  60  are opened, communication module  62  sends out a retract signal D and once signal D is received by the vehicle interface system, a step  86  instructs the pads to retract. 
     As an alternative, the vehicle interface system is equipped with a charge tapering system wherein the charging current is tapered off as the completion of a charge is approached to ensure battery cell voltage uniformity. 
     The charge mat of the instant application allows a vehicle operator to recharge an electric or hybrid electric vehicle by performing no unnecessary tasks other than parking their vehicle in a garage or other place of overnight storage. The user simply locates the charge mat in an area where the vehicle is parked for extended periods such as overnight parking. The charge mat is normally kept plugged into a conventional 110-120 volt AC outlet and the user simply aligns the vehicle and its retractable charging pads (located in the front, midsection or rear portion of the vehicle) and places the automobile in park. 
     While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.