JPH0443478A - Card information reader - Google Patents

Abstract

PURPOSE:To improve accuracy for reading by providing a signal generator to generate an alternating current signal or a pulse signal, exciting loop to convert the output of the signal generator to a magnetic field signal, detecting loop to convert a magnetic field, which is generated at the other end of the loop by the conductive loop current of a card, to a current, and detector to output a detection signal according to a detection loop signal. CONSTITUTION:This device is composed of a card information conductive loop circuit 2, exciting loop 18, detecting loop 19, exciting loop side magnetic circuit 16 and detecting loop side magnetic circuit 17, and the respective magnetic circuits 16 and 17 are made of the magnetic materials with high permeability, equipped with functions for collecting magnetic flux caused by the exciting loop 18 and the detecting loop 19, and composed of two upper and lower elements so as to insert the card between them. The detecting loop 19 and the exciting loop 18 are wound around one part of the magnetic material, and the card information conductive loop circuit 2 is used at the position of connecting the exciting loop side magnetic circuit 16 and the detecting loop side magnetic circuit 17. The magnetic flux on the exciting side and the magnetic flux on the detecting side mainly pass through the respective magnetic circuits 16 and 17 nd are not interferred each other. Thus, accuracy for reading can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a card reader for cards with conductive loops.

(Prior Art) Currently, magnetic cards are being widely used. For example, when purchasing or using a card that has a certain amount of money entered in advance, such as NTT's "Telephone Card" and JR companies'"OrangeCard," the card is used instead of money. There is a very convenient system that you can use. Similar cards are also in circulation at other private railway companies, bus companies, and even copiers. These cards are called prepaid cards, and have a predetermined number of cards as card information, and the number of cards used is reduced to <4iI precepts.

Figure 110 shows the configuration of the magnetic card, and Figure 11 shows the M of the card.
In the 0-Ryo drawing showing the R drawing, 51 is the card base material,
52 is a magnetic layer. The card information is stored as magnetic information in the magnetic layer 52 shown in FIG. In this example, there is one stripe in which magnetic information is stored, but depending on the type of card, there may be multiple stripes. Since the information on these prepaid cards is magnetically recorded directly on the card, there is a risk that the data can be easily copied or rewritten.

Additionally, bank cash card counterfeiting crimes have been occurring frequently in recent years. This involves creating a piece of plastic with magnetic tape attached to it, and then writing someone else's magnetic information onto the magnetic tape.

To solve this problem, the 1999 patent ml! 275492
No. card is proposed. The card and card operation method include a card in which card information is stored in a conductive circuit loop, a card counterfeit prevention method in which the card information by the conductive circuit loop is used as internal identification information of the card, and a card is identified using the conductive circuit loop. The card information LR East method is characterized in that the card information is changed by cutting the circuit of the conductive circuit loop on the card that stores the card information. This is a card fraud prevention method that carries low information and cross-checks it, and a card information detection method that scrapes off the magnetic material on a magnetic card and magnetically detects it.

FIG. 6 is a block diagram of an embodiment of the card of Patent Application No. 275492 of 1999. This embodiment includes a card base material 1, a conductive loop circuit 2 for reading card information in a card conductive layer loop. and a conductive loop circuit 3 used for positioning the detector.

Also, the conductive loop circuit 2 stores card information.

Alternating magnetic field coupling section 4, detector coupling section 13, and circuit cut section 5
Consisting of

FIG. 7 is a principle diagram of the card disclosed in Patent No. 11I No. 275492 of 1999. In FIG.
is the stray capacitance. The manner in which information is numbered and extracted by the conductive loop circuit 2 will be explained using a tI2 diagram.

The current generated in the alternating current signal source 6 is converted into an alternating magnetic field by the alternating magnetic field generating section 7. The magnetic field generated by the alternating magnetic field generating section 7 is magnetically coupled with the alternating magnetic field coupling section 4 and causes the alternating magnetic field coupling section 4 to generate an induced current. The induced current generated here is converted into an alternating magnetic field again in the detection amount coupling section 13, and becomes a detector current by magnetically coupling with the a-field detection section 8. The current generated by the magnetic field detection section 8 is outputted by the detection circuit 9 as a detector output. In addition, in reality, the magnetic field generator 7, the alternating magnetic field coupling section 4, and the detector coupling section 1
A stray capacitance 10 exists between the magnetic field detection section 3 and the magnetic field detection section 8, and they are also electrostatically coupled.

FIG. 8 is an actual perspective view showing how the information stored in the circuit loop 2 has been changed. It is possible to stop the current from flowing. If no current flows, no magnetic field is generated in the detector coupling section 13 and no signal appears at the output of the detection circuit.

Figure Wi9 is a perspective view of the card information reading port in Patent No. F15275492 issued in 1999.
1 is a magnetic field circuit made of magnetic material, and 1.2 is an alternating magnetic field generating section. The current generated in the alternating current signal source 6 is converted into an alternating magnetic field by an alternating magnetic field generating section 12, and the alternating magnetic field is applied to each conductive loop circuit at once. The magnetic field circuit 11 has the function of efficiently coupling magnetic fields, preventing leakage of the magnetic field to other conductive loop circuits, and preventing malfunction of the detector.

(Problem to be solved by the invention) In recent years, alteration and counterfeiting of prepaid cards has become a serious social problem, and legal and technical measures are urgently needed. The card disclosed in Patent Application No. 275492 of 1999 can provide a technical solution to this problem, but its card information reading device using conductive loops reduces the possibility of detection errors and at the same time improves accuracy in order to facilitate the detection of fraud. Improvement is essential.

The present invention was made to solve these problems, and aims to improve the reading accuracy of a card information reading device using a conductive loop.

(Means for Solving the Problems) A card information reading device according to the present invention includes a card information reading device that includes a signal generator, an excitation loop, and a detection loop detector, and a magnetic material is attached to the excitation side loop and the detection loop side. A card information reading device using a weighted balance transformer that multiplies an excitation alternating magnetic field signal and a detection signal in a detection circuit, a card information reading device consisting of an Obishiro pass filter, an amplifier, and an amplitude detector. Device,
A card information reader with an excitation signal frequency of 1 KHz to 10 GHz, a card information reader with multiple signal frequencies, and a detection output that reaches a certain level by varying the amplitude of the excitation signal. A card information reading device that measures time, a card information reading device equipped with a neutralization circuit, a card information reading device equipped with a phase shifter and a signal level converter, and a card equipped with a control unit that corrects the amount of phase and level conversion. information titg removal device,
It is a prepaid card system consisting of a conductive loop card, a card information NM reader, a card hole puncher, and a magnetic reader/writer.

(Function) In the present invention, by separating the magnetic circuit into the excitation loop side and the detection loop side using a 1gi material, leakage of dead weight is reduced, and the balance modulator, Obishiro pass filter, amplifier, and fi @ detector are By using a multi-frequency signal, it becomes resistant to external noise, and by using multiple frequencies, it is possible to balance signal leakage and coupling strength at different frequencies, and by changing the amplitude of the excitation signal, the detection output can be set at a certain level. By measuring the time it reaches, the resistance of the conductive loop can be determined. By providing a neutralization circuit and using it as a phase shifter and signal level converter, the leakage signal can be canceled out. By providing a control section, the leakage signal can be neutralized. This is done dynamically, and fraud can be prevented by incorporating a conductive loop card, a card information reader, a card hole puncher, and a magnetic reader/writer into a prepaid card system.

(Embodiment) Fig. 1 is a block diagram of a card information reading device in which a detection circuit according to the present invention is composed of a band pass filter (hereinafter referred to as BPF), an amplifier (hereinafter referred to as AMP), and an amplitude detection circuit (hereinafter referred to as AM detection). Number 2 in the 6 figures is a conductive loop circuit that stores card information. The excitation signal generated by the signal generator is converted into a magnetic field by the excitation loop and applied to the conductive loop circuit 2.

When the conductive loop circuit 1Ir2 is in a closed circuit state, a circuit current flows, and a magnetic field due to the current is detected by the detection loop. The detection signal is amplified by an AMP after external noise outside the band is removed by a BPF. A detection signal that has become sufficiently large in AMP is subjected to AM detection and output as a detection output according to the amplitude of the frequency.

FIG. 2 is a circuit diagram of a card information reading device using a multiplication circuit using a balanced modulator as a detection circuit according to the present invention. In the figure, 2 is a conductive loop circuit for storing card information, and 15 is an operational amplifier. The signal detected by the detection loop enters the input of the balanced transformer tIi as it is. Furthermore, the excitation signal of the signal generator can be balanced! By inputting it into the other input of Im, it becomes a multiplication circuit of the excitation signal and the detection signal,
This means that the detection signal is phase-detected using the excitation signal. Therefore, the phase of external noise contained in the detection signal does not match that of the excitation signal, so it does not affect the phase detection output from the balance aI device.

Therefore, this card information reading device becomes extremely resistant to external noise and the like. The operational amplifier 15 serves both as a low-pass filter that blocks leakage of the excitation signal contained in the output of the balanced modulator and as a detection output amplification circuit.

! Figure 3 is a block diagram of a card information reading device having a neutralization circuit and a control unit according to the present invention. 1 In Figure 2, 2 is a conductive loop circuit for storing card information. 0 In this embodiment, the neutralization circuit is a phase shifter. It consists of an attenuator and a mixer. The excitation signal from the signal generator is also provided to the neutralization circuit.

A portion of the excitation signal is changed in phase by a certain appropriate amount by a phase shifter.The signal level of the signal that has passed through the zero phase shifter is determined to a certain appropriate level by an attenuator serving as a signal level conversion amount. The output of the attenuator and the detection output are added together using a mixer.The amount of phase change of the 0-phase shifter and the amount of level conversion of the attenuator are set so that the level is inversely similar to the leakage of the excitation signal in the detection output. By canceling the signal and sending the detection output from which the leakage signal has been removed to the detection circuit, a highly reliable card information reader can be constructed.
In this embodiment, a part of the detection output is input to the control unit, and when no card is inserted, the phase and signal level that minimize leakage of the excitation signal to the detection signal are detected, and the phase and signal level are detected, respectively. The configuration is such that the amount of phase change and attenuation amount of the attenuator are automatically given. Therefore, it is possible to automatically correct variations in signal leakage that tend to occur when the card information reading device is commercialized, and it is possible to reduce detection errors of the card information reading device.

Figure 384 shows a card precision f using the magnetic material according to the present invention.
In Figure 0, which is an actual perspective view of the li reader, 2
is a 1 Jitt loop circuit that inputs card information.

18 is an excitation loop, 19 is a detection loop, 16 is an excitation loop side magnetic circuit made of a magnetic material, and 17 is a detection loop side a magnetic circuit made of a magnetic material. Each a low circuit is transparent a
It is made of a strong magnetic material such as I4f, has the function of collecting the magnetic flux from the excitation loop 18 and the detection loop 19, and consists of two parts between which a card can be inserted. The detection loop 19 and the excitation loop 18 are wound around a part of the magnetic material. As shown in the figure, the card information conductive loop circuit 2 is located at a position connecting the excitation loop side magnetic circuit and the detection circuit side magnetic circuit. used. The magnetic flux on the excitation side and the magnetic flux on the detection side mainly pass through their respective magnetic circuits and do not interfere with the other, so a card information reader with no signal leakage can be constructed.8 In this embodiment, the directions of the two magnetic circuits are Although the case in which the magnetic circuits are in the same direction is shown, by setting the directions of the respective magnetic circuits in different directions, leakage of the excitation signal to the detection signal due to leakage of magnetic flux can be further reduced.

The frequency of the excitation signal generated by the signal generator of the card information reading device using these card conductive loops is preferably an alternating current signal between IK Hz and 10 GHz, because if the frequency of the excitation signal is too high, This is because the coupling between the excitation loop and the detection loop becomes too tight, and the leakage signal becomes large. Furthermore, as the frequency of magnetic materials increases, internal loss increases, magnetic permeability decreases, and leakage magnetic flux increases. For amplifiers and balanced modulators, components that can be used at high frequencies are expensive.If the 0 frequency is too low, the coupling between the card conductive loop circuit and the excitation loop/detection loop becomes too loose, causing a problem with the detection signal. Signal level becomes too low.

As a means to avoid deterioration of characteristics due to specifying the frequency, it is also effective to set the frequency of the excitation signal to a plurality of frequencies.

FIG. 5 is a graph of the time change of the detection output corresponding to the time change of the excitation signal when the excitation signal of the card information reading device according to the present invention is amplitude-modulated. As shown in the graph, the level of the excitation signal a changes over time in an S* pattern. The detection output b (with a conductive loop) is when the card is inserted and the conductive loop is in a closed circuit state, and the detection output level corresponding to a can also be obtained at a high level.

The detection output of C (no conductive loop) is when the card is not inserted or the conductive loop of the card is cut, and the detection output level is much lower than that of B, and only the leakage of the excitation signal is output. The dotted line in the figure is the threshold level, and the portion where the detection output exceeds this level is shown as a solid line. The detection output of a with a conductive loop exceeds the threshold level for a considerable time.

d shows the detection output (resistive conductive loop), the level is smaller than the detection output (with conductive loop) in b, and the time it takes to reach the threshold is shorter.
Conductive loops are usually the least expensive to make from metal films or the like when mass-produced.

In this case, the resistance of the resistive film becomes negligible with respect to the flowing current. However, if this conductive loop is forged with a conductive material such as graphite, an invisible resistance will occur in the conductive loop. By measuring the ratio of the time during which the detection output level reaches the threshold and the time during which it falls below it, the resistance of the conductive loop can be determined, making it possible to discover counterfeiting.

Conductive loop card, card information N1ft removal device, card hole puncher and a gas - When the data writer is applied to a prepaid card system, the hole puncher is used to renew the circuit of the conductive pattern and detect it. It is possible to do so. Regarding the telephone card of this representative prepaid card,
Punch holes are actually punched depending on the frequency of the card. By bringing the conductive loop circuit and its bright part to the punched hole, it becomes possible to supplement the frequency of the a-air information with the conductive loop information. Cards made using this method are extremely difficult to alter or forge compared to cards that only contain magnetic information.

(Effects of the Invention) As described above, each of the cards and methods according to the present invention increases the reliability of the conductive loop card, thereby helping to prevent fraud such as card forgery and data S changing, and suppressing card crimes. It contributes to society.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a card information reading device in which the detection circuit according to the present invention is composed of a band pass filter, an amplifier, and an amplitude detection circuit, and FIG. 2 is a multiplication circuit using a balanced transformer in the detection circuit according to the present invention. A circuit diagram of a card information reading device using the wia diagram is a block diagram of a card information reading device having a neutralization circuit and a control section according to the present invention.
The figure is an actual perspective view of a card information reading device using a magnetic material according to the present invention, and Fig. 5 is a detection output corresponding to the time change of the excitation signal when the excitation W signal of the card information reading device according to the present invention is amplitude-modulated. Graph of time change,
Figure 6 is a configuration diagram of an embodiment of the card of Heisei I & 1 Patent No. 1111275492, and Figure 7 is 1999 Patent Application TR27.
5492 is a principle diagram of the card, Figure 118 is an actual perspective view showing how the information stored in circuit loop 2 has been changed, and Figure 9 is a diagram of the card information reader of Patent Application No. 275492 of Heisei 1 & 1. Configuration perspective view! ! Figure 10 is a configuration diagram of the magnetic card, and Figure Wi11 is a structural diagram of the card. DESCRIPTION OF SYMBOLS 1...Card base material, 2...A conductive loop circuit that stores card information in a card conductive layer loop, 3...A conductive loop circuit used for positioning the detector, 4...An alternating magnetic field coupling part, 5...-Circuit disconnection 11L6-... Alternating current signal source, 7... Alternating magnetic field generation section, 8... Magnetic field detection section, 9... Detection circuit, 10-... Stray capacitance, ll-...
Magnetic field circuit made of magnetic material, 12-... Alternating magnetic field generating section 13... Detector coupling section, 14... Perforation -15-...
- Operational amplifier, 16-... Excitation loop side magnetic circuit made of magnetic material, 17... Detection loop side magnetic circuit made of magnetic material 18... Excitation loop, 19... Detection loop, 5
DESCRIPTION OF SYMBOLS 1...Card base material, 52...Magnetic material layer Note that the same reference numerals in each figure indicate the same or corresponding parts. Patent applicant Nakano System Excitation Roof Co., Ltd. Fig. 2 Excitation base. 111Figure 3Figure 6Figure 9

Claims (11)

[Claims] (1) In a card information reading device that detects a loop of conductive patterns formed on a card, a signal generator that generates an AC signal or a pulse signal, an excitation loop that converts the signal generator output into a magnetic field signal, A card information reading device comprising a detection loop that converts a magnetic field generated at the other end of the loop by a conductive loop current into a current, and a detector that outputs a detection signal based on the detection loop signal. (2) In the card information reading device of Claim 1,
A card information reading device characterized in that a magnetic material that collects magnetic flux is arranged on an excitation side loop and a detection loop side so that their magnetic circuits are independent. (3) In the card information reading device of Claim 1,
A card information reading device characterized in that the detection circuit uses a multiplication circuit that multiplies the signal generator output and the detection signal. (4) In the card information reading device of claim 1, the detection circuit includes an Obishiro pass filter whose center frequency is the frequency of the detection signal, an intensifier that amplifies the detection signal, and an intensified detection signal. A card information reading device comprising an amplitude detector that converts into a detection output. (5) In the card information reading device of Claim 1,
The frequency of the excitation signal created by the signal generator is 1KH.
A card information reading device characterized in that the frequency range is from z to 10 GHz. (6) In the card information reading device of Claim 1,
A card information reading device characterized in that an excitation signal generated by a signal generator has a plurality of frequencies. (7) In the card information reading device of Claim 1,
A card information reading device characterized by changing the vibration of an excitation signal and measuring the time during which a detection output reaches a certain predetermined signal level. (8) In the card information reading device of Claim 1,
A card information reading device characterized by being provided with a neutralization circuit that cancels leakage of an excitation signal generated by a signal generator into a detection signal. (9) In the card information reading device of claim 8,
1. A card information reading device comprising a neutralizing circuit comprising a phase shifter that changes the phase of an excitation signal and/or a signal level converter that changes the signal level of the phase shifter output. (10) The card information reading device according to claim 9, which includes a control unit that detects leakage of the detection signal when the card is not inserted and corrects the phase amount to be applied to the phase shifter and the level conversion amount to the signal level converter, or one of them. A card information reading device characterized in that: (11) A card with a loop of magnetic information and a conductive pattern, a card information reader that detects the conductive loop of the card, a card hole puncher that cuts the conductive loop of the card and changes the card information, and a card that records the magnetic information of the card. A prepaid card system consisting of a magnetic reader/writer that reads and writes, and configured to supplement the frequency of magnetic information with conductive loop information.