Technical Field
The invention pertains to license plate frame assemblies having modulators, transponders or radio frequency identification devices (RFIDs) incorporated therein. Further, the invention pertains to methods of attaching transponders, modulators, and RFIDs to vehicles.
Background of the Invention
Remote identification of a vehicle is a process whereby a vehicle is identified by a machine external to the vehicle. Many applications exist for remote vehicle identification. Such applications include, for example, toll collection booths and fuel stations. Toll booths capable of remotely identifying vehicles could automatically assess charges against the owners of passing vehicles, and then bill the owners digitally. This would enable persons to pay tolls without having to slow down at the toll booths to deposit currency. As cars would not have to slow at the toll booths, traffic through the toll booths would be substantially unimpeded by the presence of the toll booths; saving time for persons travelling the tolled roads.
Remote identification of vehicles by fuel stations would enable the stations to automatically reset a fuel pump and begin charging a vehicle's owner for fuel dispensed to a vehicle. This would save time at gas stations that is otherwise utilized for persons to pay their fuel filling bill. Also, it could reduce personnel required at gas stations, as many of the functions of such personnel would become automatic. Also, as vehicles would be remotely identified before they were filled with gas, there would be little opportunity for would be thieves to fill their tanks and leave without paying.
For the above-discussed reasons, it is desirable to develop methods and apparatuses for remotely identifying vehicles.
Summary of the Invention
In one aspect, the invention encompasses a method of forming a license plate frame. A license plate frame substrate is provided. The license plate frame substrate is configured to mount to a vehicle. The license plate frame substrate is further configured to receive and retain a license plate. A transponder is mounted to the license plate frame substrate.
In another aspect, the invention encompasses a method of attaching an RFID to a vehicle. A license plate frame is provided. The license plate frame is configured to mount to a vehicle. The license plate frame is further configured to receive and retain a license plate in a configuration wherein characters on the license plate are viewable to persons proximate the vehicle when the license plate frame with a license plate retained therein is mounted to the vehicle. An RFID is mounted to the license plate frame. The license plate frame is utilized to mount a license plate to the vehicle.
In another aspect, the invention encompasses a vehicle. The vehicle has an interior compartment and a body surrounding the interior compartment. The body has an exterior surface. The vehicle also has an RFID mounted to the exterior surface of the body. The RFID includes an integrated circuit.
Brief Description of the Drawings
Preferred embodiments of the invention are described below with reference to the following accompanying drawings.
FIG. 1 is a front view of a license plate holder in accordance with the present invention.
FIG. 2 is a back view of the license plate holder of FIG. 1.
FIG. 3 is an exploded side view of the license plate holder of FIG. 1.
FIG. 4 is a back cross-sectional view of an alternate embodiment of a license plate frame of the present invention.
FIG. 5 is an exploded side view of the FIG. 1 license plate holder being mounted onto a vehicle.
FIG. 6 is a zoom view of the region labelled "6" in FIG. 5.
Detailed Description of the Preferred Embodiments
This disclosure of the invention is submitted in furtherance of the constitutional purposes of the U.S. Patent Laws "to promote the progress of science and useful arts" (Article 1, Section 8).
In one aspect, the invention encompasses a method for remote identification of a vehicle wherein a modulating device is attached to an exterior of the vehicle. The modulating device can define a transponder. In a preferred aspect of the invention, the transponder is comprised by an RFID. Example RFID circuitry is disclosed in the commonly assigned U.S. patent application Ser. No. 08/705,043, filed Aug. 29, 1996, which is hereby incorporated by reference. RFID circuitry associated with vehicles is disclosed in commonly assigned U.S. patent application Ser. No. 08/759,737, filed Dec. 6, 1996, which is hereby incorporated by reference. In applications of the invention in which a modulator is incorporated in an RFID, the modulator is preferably a backscatter modulator. Backscatter modulators are preferred for RFIDs for economy of power.
A preferred method for mounting a modulator to an exterior of a vehicle is to incorporate the modulator into a license plate frame. A first embodiment license plate frame 10 of the present invention is described with reference to FIGS. 1-3. License plate frame 10 comprises a license plate frame substrate 12 configured to mount to a vehicle and configured to receive and retain a license plate. License plate frame substrate 12 comprises a plurality of holes 14 configured for receiving screws (shown in FIG. 6 as 68). Such screws can be inserted through a license plate (shown in FIG. 6 as 66) and into receptacles on a vehicle (not shown) to secure the license plate to the vehicle.
License plates typically have a surface comprising a series of alpha-numeric characters unique to the license plate and utilized for identifying an owner of the license plate. License plate frame substrate 12 comprises a perimeter 18 around an orifice 16. The perimeter is configured to retain a license plate and overlay the surface of the license plate comprising the alpha-numeric characters. The alphanumeric characters are viewable through orifice 16 to persons proximate the license plate when the perimeter is overlaid on the license plate. In the front view of FIG. 1, license plate frame 10 resembles a conventional license plate frame. License plate frame 10 comprises a widened, or downwardly deepened, portion 20 of the perimeter 18. A front surface of widened portion 20 can be provided with symbols and logos for, for example, advertising purposes. Exemplary symbols and logos are shown in FIG. 1.
License plate frame 10 will preferably be from about 1/8 inch thick to about 1 inch thick, and will most preferably be about 1/4 inch thick.
In the back view of FIG. 2, it is shown that perimeter 18 can comprise a pair of different elevation surfaces 22 and 24, with surface 24 being recessed relative to surface 22. Perimeter 18 is preferably configured such that a license plate will fit snugly within recessed portion 24. License plate frame 10 can be dimensioned, for example, for retaining European-style license plates or U.S.-style license plates.
The back surface of widened portion 20 has an opening, or recess, 26 provided therein. Substrate 12 comprises a substantially planar outermost surface 56 proximate opening 26. An RFID 28 is mounted within opening 26. RFID 28 comprises an integrated circuit 30 and a loop antenna 32. Integrated circuit 30 and antenna 32 are bonded to a circuit card assembly 37, and comprise outermost surfaces 52 and 54, respectively. Integrated circuit 30 and antenna 32 are electrically connected by interconnects which, in the shown preferred embodiment, are beneath circuit card 37 and not viewable in the orientation of FIG. 2. Loop antenna 32 can be formed, for example, by printing a conductive material onto circuit card 37. Alternatively, loop antenna 32 can be formed by placing a conductive strip within opening 26. Antenna 32 is preferably configured (e.g. sized) to operate at microwave frequencies. If transmission using backscatter modulation is desired a dipole antenna is provided on circuit card assembly 37 in addition to loop antenna 32. The dipole antenna is used for backscatter modulation, and loop antenna 32 is used for reception.
A battery holder 34 is also provided within opening 26 and mounted to circuit card 37. Battery holder 34 comprises an outermost surface 50. A battery 36 is provided within battery holder 34 and in electrical connection with integrated circuit 30 through electrical interconnects. In the shown embodiment, the interconnects are beneath circuit card 37 and not visible in the FIG. 2 view. Battery 36 is preferably removably retained within holder 34 such that battery 36 can be easily replaced when it drains. Alternative methods for mounting battery 36 in electrical connection with integrated circuit 30 are, for example, soldering and gluing. In still other alternative embodiments, battery 36 can be provided as a component part of integrated circuit 30.
A cover 38 (shown in FIG. 3, but not shown in FIG. 2 for clarity) is provided over opening 26 to protect RFID 28 and battery 36. Cover 38 preferably overlays an entirety of opening 26 to protect the electronic components within opening 26 from dust and moisture. Openings 42 are provided within substrate 12 and configured for receiving screws 40 which secure cover 38 to substrate 12. Screws 40 preferably comprise flat heads to minimize damage that screws 40 can otherwise cause to a vehicle to which frame 10 is attached. Also, screws 40 can comprise heads configured to make the screws more difficult to remove than to insert. Such heads, which may be referred to as anti-theft heads, can impede persons from swapping RFID devices from one license plate frame with another.
A sealant layer 44 is preferably provided around a periphery of opening 26, as well as around peripheries of openings 42. Sealant layer 44 can comprise, for example, flexible rubber material. Cover 38 preferably sealingly engages sealant layer 44 to prevent moisture from entering opening 26 after cover 38 is in place. In the shown embodiment, cover 38 is removably mounted to license plate frame substrate 12. In other embodiments of the invention, cover 38 can be relatively permanently mounted to substrate 12 by, for example, soldering, welding or gluing.
In the shown embodiment, opening 26 extends only partially into substrate 12. In alternate embodiments, opening 26 can be configured to extend entirely through substrate 12. However, most preferred is that opening 26 extend only partially into substrate 12, and be deep enough such that outermost surfaces 50, 52 and 54 of battery housing 34, integrated circuit 30 and antenna 32, respectively, do not extend outwardly beyond outermost surface 56 of substrate 12 proximate opening 26. Such relative configuration of outermost surfaces 50, 52 and 54 relative to outermost surface 56 ensures that cover 38 can fit tightly over opening 26.
License plate frame substrate 12 can consist essentially of an insulative material, such as high impact plastic, or polyvinyl chloride (PVC), and can be formed by injection molding the material into the configuration shown in FIGS. 1-3. Such materials will not interfere with radio frequency communications. Opening 26 can be formed during the injection molding process. Alternatively, opening 26 can be formed after the injection molding process by, for example, cutting opening 26 into license plate frame substrate 12.
FIG. 4 shows an alternative embodiment of a license plate frame of the present invention. In referring to FIG. 4, similar numbering to that used above in describing FIGS. 1-3 will be utilized, with differences indicated by the suffix "a" or by different numerals. License plate frame 10a comprises a substrate 12a which preferably comprises an insulative material, such as PVC or plastic. Substrate 12a comprises a perimeter 18a surrounding an orifice 16a. Perimeter 18a is configured to extend around an outer surface of a license plate (not shown). Antenna 32a is a loop antenna configured to extend entirely around perimeter 18a and surround orifice 16a. Loop antenna 32a is electrically connected to integrated circuit 30a through interconnects which are not shown. Only a portion of antenna 32a is within opening 26a. Antenna 32a can be formed, for example, by providing a conductive strip within substrate 12a as the substrate is injection molded from a plastic material. The larger loop antenna 32a can provide increased range and performance relative to the smaller loop antenna 32 (shown in FIG. 2).
Opening 26a is shown smaller than opening 26 (shown in FIG. 2) because opening 26a does not encompass an entirety of an antenna as does opening 26. Opening 26a can also be the same size as opening 26, or larger than opening 26, in alternative embodiments of the invention.
Referring to FIGS. 5 and 6, license plate frame 10 of FIGS. 1-3 is shown in an exploded view being mounted to a vehicle 60. Vehicle 60 comprises an interior compartment 62 configured for retaining passengers and an exterior surface 64 surrounding interior compartment 62. Circuit card assembly 37 is mounted to license plate frame substrate 12 as described above in describing FIGS. 1-3. Also, cover 38 is adhered over circuit card assembly 37 with a screw 40 as described above. After cover 38 is adhered over circuit card assembly 37, license plate frame 10 is provided over a license plate 66 and utilized to secure license plate 66 onto exterior surface 64 of vehicle 50. Specifically, one or more screws 68 are provided through openings 14 (shown in FIGS. 1-3) and threadedly engaged with vehicle 60 to retain license plate frame 10 and license plate 66 to vehicle 60.
In the shown preferred embodiment, screws 40 are positioned between license plate frame 10 and vehicle exterior 64. Such positioning of screws 40 renders it is more difficult for would be thieves to steal RFID circuitry 28 from license plate frame 10. To further impede stealing of RFID circuitry 28, screws 68 can be configured to be more difficult to remove than to insert, or to be removable only with specialized tools. It is noted that theft of license-plate-framemounted RFID devices of the present invention can be further diminished by taking pictures of remotely identified cars. For instance, toll booths are typically equipped with cameras that read license plates of cars passing by to identify vehicles that pass through without paying. Toll booths equipped to remotely identify cars can utilize digital processing equipment associated with the toll booths, or a human operator, to rapidly associate a license plate number with an improper RFID signal (e.g. for an RFID device reported as being stolen) so that a thief of the RFID can be identified and apprehended.
Although the shown embodiment is described as having RFID 28 powered by a battery 36, alternative embodiments can be constructed wherein RFID 28 is powered by an electrical system of vehicle 60. In such alternative embodiments, power from the vehicle can be stepped down from 12 volts to a voltage more reasonable for driving RFID 28, such as about 3 volts.
The present system for mounting an RFID to an exterior of a vehicle has advantages over systems in which an RFID is merely retained within a passenger compartment of a vehicle. For instance, RFIDs sometimes will not work through the window heaters frequently found associated with vehicle windows. The present invention places the RFID externally of any vehicle windows, and thus avoids the problem of transmitting through a window heater. Also, by having a RFID device relatively permanently adhered to the vehicle in the form of a license plate frame, it is less likely that a person driving the vehicle will forget the RFID device before traveling in the vehicle, lose the RFID device, or confuse multiple RFID devices in multi-vehicle households.
In compliance with the statute, the invention has been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the invention is not limited to the specific features shown and described, since the means herein disclosed comprise preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted in accordance with the doctrine of equivalents.