U.S. patent application number 12/239472 was filed with the patent office on 2010-04-01 for shielded money clip.
Invention is credited to Morgan Cox, Glenn Styron.
Application Number | 20100078101 12/239472 |
Document ID | / |
Family ID | 42056110 |
Filed Date | 2010-04-01 |
United States Patent
Application |
20100078101 |
Kind Code |
A1 |
Styron; Glenn ; et
al. |
April 1, 2010 |
Shielded Money Clip
Abstract
A money clip is disclosed with RF shielding characteristics to
prevent skimming of stored magnetic and/or digital data in credit
cards, quick pay devices, and other items that include magnetically
stored personal data. The clip is formed of multiple layers of
carbon cloth arranged to prevent transmission of radio frequencies
in the range used to acquire the data. The layers are formed using
a resin to bind the layers and the formation process resists the
introduction of air into the device. The clip is strong enough to
resiliently hold money, credit cards, and the like without losing
its shape, and the shielding properties protect the contents for
unauthorized data acquisition.
Inventors: |
Styron; Glenn; (Long Beach,
CA) ; Cox; Morgan; (Long Beach, CA) |
Correspondence
Address: |
FULWIDER PATTON LLP
HOWARD HUGHES CENTER, 6060 CENTER DRIVE, TENTH FLOOR
LOS ANGELES
CA
90045
US
|
Family ID: |
42056110 |
Appl. No.: |
12/239472 |
Filed: |
September 26, 2008 |
Current U.S.
Class: |
150/137 ;
150/131; 150/147; 24/67.3; 24/67.9 |
Current CPC
Class: |
Y10T 24/205 20150115;
A45C 2011/186 20130101; A45C 1/06 20130101; A45C 2001/062 20130101;
Y10T 24/202 20150115 |
Class at
Publication: |
150/137 ;
150/147; 150/131; 24/67.9; 24/67.3 |
International
Class: |
A45C 1/00 20060101
A45C001/00; A45C 11/18 20060101 A45C011/18; A44B 21/00 20060101
A44B021/00 |
Claims
1. A clip for retaining money, credit cards, and the like,
comprising a single plate folded into a clip structure having a
first and second ends opposed to one another, said first and second
ends resiliently biased to form a small gap therebetween for
retaining said materials with magnetically and/or digitally stored
information, said plate having: a first layer of carbon cloth
having a cross hatch pattern of carbon fibers; a second layer of
carbon tape having a unidirectional orientation of carbon fibers;
and a third layer of carbon cloth having a cross hatch pattern of
carbon fibers.
2. The clip of claim 1 further comprising a fourth layer of copper
wire mesh disposed between said first and third layers.
3. The clip of claim 1 wherein said first layer of carbon cloth and
third layer of carbon cloth have a density of 200 grams per square
meter.
4. The clip of claim 1 wherein the first layer of carbon cloth and
the third layer of carbon cloth are arranged in a twill pattern
having two weft and two warp threads.
5. The clip of claim 1 wherein the second layer of carbon fiber
tape has a density of 150 grams per meter squared to 250 grams per
meter squared.
6. The clip of claim 1 wherein a combined weight of the first,
second, and third layers combined have a density in a range of 600
grams per meter squared to 650 grams per meter squared.
7. The clip of claim 1, wherein the plate comprises no more than
four layers.
8. The clip of claim 1, wherein an orientation of carbon fibers in
said second layer is perpendicular to a longitudinal direction of
the spine.
9. The clip of claim 1, further comprising a resin layer disposed
between said first and second layers and between said second and
third layers.
10. The clip of claim 9 wherein the resin is selected from epoxy
and polyester.
11. The clip of claim 9 wherein the concentration of resin to
carbon cloth is in a range of 25 to 45 percent.
12. The clip of claim 1 further comprising an absence of trapped
air between said first and third layers.
Description
BACKGROUND
[0001] The present invention is related to clips carried in pockets
or the like and used to store cash, credit cards, and other
valuables, and more particularly to a clip that uses one or more
protective carbon and RF shielding sheets to shield the data held
in the contents of the clip from unauthorized pirating while
protecting the contents with a sturdy, robust structure.
[0002] Money clips are well known in the art. Favored by men who
prefer a slim profile without the bulk of a wallet, money clips are
typically carried in a front or back pocket and used to hold cash,
credit cards, and other valuables. The clip has a resilient tongue
member that presses against a spine to capture currency. Examples
of such clips can be seen in U.S. Pat. No. D283,844, U.S. Pat. No.
4,674,953, U.S. Pat. No. D400,466, and U.S. Pat. No. 6,327,749.
[0003] Security issues have arisen in connection with the storage
of newer generation credit cards. These credit cards have personal
data magnetically and digitally stored on the card, including the
owner's name, credit card number, expiration data, and even the
address or social security number of the card holder. Because this
information is stored magnetically and digitally, the information
can be acquired or stolen by a device placed in proximity with the
credit card using radio frequency (RF) waves, called "skimming."
The RF waves can pass through clothing and even leather to skim
information from credit cards or other cards carried in a wallet or
purse without the owner's consent or even knowledge. This stolen
information can then be used to purchase items over the internet
and the like, and the card holder is unaware that his or her
information has been stolen until the bill arrives sometime
later.
[0004] Radio-Frequency Identification (RFID) is a general term for
small, wireless devices that emit unique identifiers upon
interrogation by RFID readers. One form of an RFID device that is
expected to gain popularity in the near future is known as an EPC
(Electronic Product Code) tag. They are sometimes viewed in effect
as wireless barcodes, i.e., they provide identification, but not
digital authentication. The term RFID, however, denotes not just
EPC tags, but a spectrum of wireless devices of varying
capabilities. More sophisticated and expensive RFID devices can
offer cryptographic functionality and therefore support
authentication protocols. One of the most popular of such devices
is known as a Digital Signature Transponder (DST). Manufactured by
Texas Instruments, DSTs are deployed in several applications that
are notable for wide-scale deployment and the high costs (financial
and otherwise) of a large-scale security breach. These include
electronic payment devices such as in the Exxon-Mobil SpeedPass.TM.
system, Mastercard's Paypass.TM. system, American Express'
ExpressPay.TM. system, and Visa's payWave.TM. system.
[0005] A DST consists of a small microchip and antenna coil
encapsulated in a plastic or glass capsule, or implanted into a
credit card. It is a passive device, which is to say that it does
not contain an onboard source of power, but rather receives its
power via electromagnetic inductance from the interrogation signal
transmitted by the reading device. This design choice allows for a
compact design and long transponder life. A DST contains, for
example, a secret, 40-bit cryptographic key that is
field-programmable via RF command. In its interaction with a
reader, a DST emits a factory-set (24-bit) identifier, and then
authenticates itself by engaging in a challenge-response protocol.
The reader initiates the protocol by transmitting a 40-bit
challenge. The DST encrypts this challenge under its key and,
truncating the resulting ciphertext, returns a 24-bit response. It
is thus the secrecy of the key that ultimately protects the DST
against cloning and simulation.
[0006] Recent developments in the field of cryptology have allowed
the reverse engineering of the key, enabling anyone with a scanner
to retrieve the information off the DST and use the information for
improper purposes. This can lead to identity theft, larceny, and
other assorted events that the user would like to avoid. The
present invention is directed to a device for diminishing the risk
of skimming and other forms of illicit data acquisition by blocking
the radio frequency energy that powers the DST or other data
storage device, preventing the transmission of personal data.
SUMMARY OF THE INVENTION
[0007] The present invention is a money clip that resists skimming
and other forms of data acquisition using a combination of carbon
layers with or without RF blockers such as a copper wire mesh, to
block RF transmission. A carbon fiber matrix is created in a vacuum
environment to prevent air voids from impregnating the material.
Alternating layers having strands or fibers offset from the
surrounding layers to create a barrier that resists the
transmission of radio waves. A unidirectional carbon fiber cloth is
preferably sandwiched between adjoining cover layers using a resin
such as epoxy or polyester to bind the layers. The number of layers
is preferably between three and four, where more than four layers
can detrimentally affect the tightness of the clip's "spring." An
RF blocker such as a copper screen or wire mesh may also preferably
be incorporated into the structure to further resist penetration of
RF waves. The resultant composite money clip is lightweight,
strong, and resists skimming of information on cards and other
devices held therein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1a is an elevated, perspective view of a first
preferred embodiment of the present invention;
[0009] FIG. 1b is a cross-sectional view of a first preferred
embodiment of the present invention;
[0010] FIG. 2a is a diagram of an arrangement of carbon layers in a
first preferred embodiment;
[0011] FIG. 2b is a diagram of an arrangement of a second preferred
embodiment including a copper mesh screen layer;
[0012] FIG. 3 is a chart showing various results of a load spring
test for different material compositions;
[0013] FIG. 4 is a plot of the shielding effectiveness for a sample
material and sample frequency range; and
[0014] FIG. 5 is a plot of the shielding effectiveness of a copper
wire mesh for various radio frequencies.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] The money clip 10 of the present invention is preferably
formed of a single planar member of material that is substantially
impenetrable to radio frequency waves in a specified frequency
range. The material is formed into a clip 10 having a spine 12 and
a tongue 14, as shown in FIGS. 1a and 1b. The tongue 14 is
preferably in the range of two to two and one half inches long, and
more preferably in the range of two and an eighth to two and a
quarter inches. The tongue 14 includes an upwardly turned lip 16
that facilitates the sliding of paper bills, credit cards, and the
like into the clip 10. The upwardly turned lip 16 has a distal end
18 having a of slight radial curvature of approximately one third
of an inch. The spine 12 is preferably formed of a relatively flat,
planar section in proximity with the bottom surface of the tongue
14, and curved slightly toward a juncture 13 between the spine 12
and tongue 14. The juncture 13 is preferably a smooth transition
from the respective ends of the spine 12 and tongue 14 to form a
radial curvature. The shape of the clip can be stamped from a die
out of a single sheet of carbon material, or formed through other
known shaping methods.
[0016] An exemplary clip will have a width of 11/2'' to 2'',
measured along the spine and the leading edge of the tongue. The
tongue is preferably about 21/8'' to 21/4'' in length, whereas the
upper extension is approximately 13/4'' to 2'' in length. The
upturned lip 16 has an angular extension of approximately
forty-five degrees from horizontal, and the distance from the upper
surface 20 of the spine to the bottom of the lip 16 is
approximately 1-4 mm. The radius of the juncture 13 is
approximately one sixth of an inch.
[0017] A series of carbon laminate sheets are stacked to form the
sheet that is shaped into the present invention. The carbon sheets
are held together with a resin (not shown) such as polyester or
epoxy, where epoxy has more preferable traits. The formation of the
sheet can be by a wet laminate process whereby dry carbon fiber
cloth is coated with resin that is applied to the material at the
time of formation or pre-impregnated with the resin. In a preferred
embodiment, the resin concentration is approximately 25%-45%,
maintaining the preferred fiber arrangement set forth below.
[0018] The layers of woven carbon fiber cloth have been shown to
provide sufficient shielding of radio frequency waves for
frequencies common to the application at hand. As shown in FIG. 2a,
a preferred orientation of a woven cloth 40 includes a first row of
fibers 44 arranged in a parallel configuration, adjacent a second
row of fibers 46 arranged perpendicular to the first row of fibers.
Other woven patterns can include alternating fibers in
perpendicular directions, or variations thereof. The clip 10 of the
present invention preferably includes two such layers 40, 60. This
cross-hatched pattern incorporates a 200 g/M.sup.2 twill weave (two
weft, two warp threads). A preferred construction of the clip 10 of
the present invention also includes a unidirectional carbon fiber
tape 22 sandwiched between two layers of carbon cloth 24, or
"twill." The unidirectional tape 22 is preferably oriented traverse
to the longitudinal direction of the spine 12 of the clip 10, and
further serves to reinforce the shape of the clip. The
unidirectional carbon fiber cloth can be 150 g/M.sup.2 to 250
g/M.sup.2, but can be lower if the surrounding cloth is heavier to
offset the heavier twill or vice versa. The arrangement of the
outside cloth 40, 60 in a cross-hatch pattern in combination with
the unidirectional tape 22 serves to block the malicious radio
frequency waves from penetrating the clip 10.
[0019] It is preferred that no more than four layers of carbon
fiber are used to form the sheet, as the resiliency of the clip
becomes compromised as it becomes thicker with excess layers. That
is, the ability to slip money and credit cards into the clip
becomes more difficult as the number of layers exceeds four due to
the rigidity of the clip. Where four layers of material are used,
it is preferred that the cloth weight is reduced to between 600-650
g/M.sup.2 for the carbon fiber matrix weight.
[0020] An alternative embodiment of the clip is shown in FIG. 2b,
where a layer of copper wire mesh 70 is incorporated into the
composite. The copper wire mesh 70 is a further RF inhibitor, and
further restricts the intrusion of RF waves. The copper mesh can
be, for example, described as RCMS 1002 nickel metalized non woven
mesh sold by Real Carbon LLC of Hood River, Oreg. FIG. 5
illustrates a plot of shielding effectiveness for the wire mesh
versus various radio frequencies between 1 kHz and 10 GHz. The plot
reflects a greater than 100 dB reduction in transmission for three
different wire mesh configurations (16 mesh 0.011 copper, 22 mesh
0.015 copper, and 100 mesh 0.0045 copper) for frequencies less than
1 MHz. Above 1 MHz, the reduction in dB is approximately linear
between 1 MHz and 10 GHz, where a 20-30 dB reduction is measured at
10 GHz.
[0021] The carbon fiber composite matrix is preferably formed such
that no air is introduced into the layers. To ensure that the sheet
is free of air voids, the part is subject to pressure during the
molding process. Methods for applying pressure include vacuum bag,
autoclave, or compression bladder mold, and other such methods that
can suitably withstand the necessary strength requirements for
shaping the part.
[0022] FIG. 3 is a chart showing the failure analysis for several
different matrix compositions. Five different samples were tested,
including: (a) 200 gram twill/unidirectional tape 949/twill; (b)
200 gram twill/Unidirectional tape/twill; (c) twill/twill, Uni, 200
gram Twill; (d) Twill, uni, Twill Dry (spray glue); and (e) Twill,
uni, Twill (wet laminate). The materials were manufactured and
tested by Pirate Carbon, Inc. of Long Beach, Calif. Various loads
were applied to the five materials to demonstrate the strength and
flexibility of the materials, as reflecting in the cracking load
and the failure load, where failure is deemed to be permanent
deformation or breakage of the part. The twill/unidirectional
tape/twill configuration, with or without a fourth twill layer, was
shown to be the most effective at resisting cracking and failure.
The test also demonstrated that the materials tested in FIG. 3
exceeded that of present day clips by a substantial amount,
establishing the effectiveness and suitability of the materials set
forth therein for its intended purpose.
[0023] The materials tested in the failure analysis were then
tested for RF transmittance to determine their effectiveness as RF
blockers. The shielding effectiveness (SE) test is used to quantify
the shielding characteristics for each material over the frequency
range of 1 MHz to 1 GHz. The testing was performed by Stork Garwood
Labs, Inc. of Pico Rivera, Calif. 90660. During the SE test, each
material was held in place in a pre-cut precision milled aluminum
frame with the edges sealed using industrial tape to prevent RF
leakage around the edges. The aluminum frame was assembled in an
accommodating access port in the bulkhead shared by two adjoining
EMC shielded enclosures with ambient RF attenuation (shielding)
properties of 70 to 80 dB.
[0024] The SE test effort was performed on each material sample
from 1 MHz to 1 GHz in the following stages: [0025] 1 MHz-25 MHz
[0026] 13 MHz-14 MHz (RFID scanner critical frequency range) [0027]
22 MHz-24 MHz [0028] 20 MHz-100 MHz [0029] 100 MHz-200 MHz [0030]
200 MHz-1 GHz
[0031] To determine the SE characteristics of each material sample
in numeric terms of decibels (dB) over each frequency range, a
reference was first established through the precision milled
aluminum frame with no material sample in it. For the frequency
range of 1 MHz-25 MHz, two 41'' monopole antennas with matched
architecture properties were used: a passive one as a transmitting
antenna connected to an RF power amplifier connected to a signal
generator; and an active one as a receiving antenna connected to a
spectrum analyzer, connected to an x-y plotter. Both antennas were
vertically polarized throughout the test effort.
[0032] The RF output of the signal generator was adjusted to a
fixed power output setting producing a maximum dynamic range
(signal to noise ratio) into the RF power amplifier and programmed
to sweep continuously and repetitively in 1 MHz resolution
increments from 1 MHz to 25 MHz. Each antenna was positioned with
its center beam width axis at the geometric center of the hole in
the plate accommodating each sample at a distance of approximately
one half meter from the plate, thus approximately one meter from
the leading edge of each antenna.
[0033] The settings on the spectrum analyzer were adjusted to
display a usable trace (using continuous and repetitively swept
peak maximum hold weighting) expressed in terms of dB .mu.V
represented by the dashed line in FIG. 4. Once this standard
reference was established and recorded, all signal generator, power
amplifier, spectrum analyzer and antenna settings were fixed. Then,
each material sample was secured in the aluminum frame, and the
resulting signal was displayed (represented by the solid line in
the plot of FIG. 4).
[0034] The shielding effectiveness (SE) of each material sample was
thus calculated using the form:
SE(dB)=Standard Reference Trace(dB.mu.V)-Material Sample
Trace(dB.mu.V)
The test was repeated for frequency ranges 13 MHz-14 MHz and 22
MHz-24 MHz.
[0035] The test was also repeated in the same way for the frequency
ranges of 20 MHz-100 MHz and 100 MHz-200 MHz, using two passive
biconical antennas with matched architecture properties: one as a
transmitting antenna connected to the RF power amplifier connected
to the signal generator; and the other as a receiving antenna
connected to the spectrum analyzer connected to the x-y plotter.
Both antennas were vertically polarized throughout the test effort.
The test was repeated again as above for the frequency ranges of
200 MHz-1 GHz.
[0036] The graph above shows the shielding effectiveness for the
embodiment of FIG. 2a for frequencies between 2.5 MHz and 1 GHz. It
can be seen from the graph that the shielding effectiveness ranges
from approximately 25 dB at the lower frequencies to a peak of
about 55 dB at the intermediate frequencies, and dropping to about
42 dB at the highest frequencies. The resultant shielding
effectiveness reflects a dramatic attenuation of RF frequency
intrusion into the clip of the present invention, which is further
enhanced by including the copper mesh screen as illustrated in FIG.
2b.
[0037] The foregoing descriptions of the preferred embodiments are
intended to fulfill the inventor's obligation to disclose the best
modes for carrying out the invention, but are not intended to limit
the invention to any disclosed embodiment or depictions. Rather,
the scope of the invention is properly determined by the appended
claims, using the ordinary and customary meaning of the words
therein, consistent with the foregoing disclosure. It is recognized
that those of ordinary skill in the art would readily come up with
modifications and alterations to the above-described embodiments,
and such modifications and alterations are properly deemed within
the scope of the invention.
* * * * *