Apparatus and method for recharging a vehicle

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.

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's batteries can be recharged at the driver'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.

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.times.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.times.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.times.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'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'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.