JPH0226263B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a card type discrimination circuit for a magnetic card reader.

Magnetic cards are mainly known as those based on the NTT standard and those based on the ISO standard. FIG. 1 shows an NTT standard magnetic card 1, on the front side of which a magnetic stripe 2 is formed. This magnetic stripe 2 has one track, and its recording density is specified as 210 BPI (Bits Per Inch). FIG. 2 shows an ISO standard magnetic card 3, on the back of which a magnetic stripe 4 is formed. This magnetic stripe 4 is provided with three tracks 41 to 43.
Each of the 43 recording densities is different. truck 41
The recording density of the track 42 is specified to be 210 BPI, and the recording density of the track 42 is specified to be 75 BPI. As shown in FIG. 3, the track positions of both magnetic cards 1 and 3 are track 2 on magnetic card 1 and tracks 41 and 42 on magnetic card 3 when both magnetic cards 1 and 3 are overlapped.
The positional relationship is such that they almost entirely overlap.

Conventional magnetic card readers only use NTT standard magnetic cards 1 and ISO standard magnetic cards 3, and recently NTT
Development of a magnetic card reader that can use both standard magnetic cards 1 and ISO standard magnetic cards 3 is underway. Along with this, it is necessary to distinguish between both magnetic cards.

In view of these circumstances, it is an object of the present invention to provide a card type determination circuit for a magnetic card reader that can determine the type of magnetic card inserted into the magnetic card reader.

The present invention will be described in detail below with reference to the drawings.

Magnetic cards include not only the aforementioned NTT standard magnetic card 1 and ISO standard magnetic card 3, but also magnetic stripes 2 and 4 according to NTT standards and ISO standards on the front and back of one card, as shown in Figure 4. Ta
There is also an NTT/ISO standard common type magnetic card 6, and when the magnetic head reads information from the first track 41 and second track 42 of the ISO standard magnetic card 3, the read signal is transmitted to the first track 41 and the second track 42, respectively. The frequencies differ due to the different recording densities of the two tracks 42. An example of a card type discriminating circuit for a magnetic card reader to which the present invention is applied can discriminate between the magnetic cards 1, 3, and 6, and the example will be described next.

As shown in FIG. 5, a card gate section 14 is provided on the front side of a main body 13 of the magnetic card reader, and a circuit section 15 is provided on one side of the main body 13. A card insertion slot 19 is provided in the card gate section 14. As shown in detail in FIGS. 6 and 7, the card gate section 1
4, magnetic heads 16 and 17 for card detection are arranged above and below the magnetic card passage so as to face each other across the magnetic card passage. The lower magnetic head 17 is fixed to the gate part 14, whereas the upper magnetic head 16 is provided so as to be movable in the vertical direction, and is attached to a head holding member 18.
The magnetic stripe of the magnetic card inserted from the card insertion slot 19 can be pressed from above and slid into close contact with the magnetic stripe, and the pressing force of the head holding member 18 can also cause the magnetic card to slide downward. It is designed so that it can be brought into close contact with the magnetic head of the device. Card detection magnetic head 16,1
A shutter is provided between the card reader body 13 and the card reader body 13 to open and close the magnetic card passage.
Not shown. This shutter is connected to, for example, a solenoid that is a driving member, and is normally biased by a spring in a direction to shield the magnetic card passage.When the magnetic heads 16 and 17 detect a magnetic card inserted from the insertion slot 19, The solenoid operates to open the shutter, allowing the magnetic card to be inserted further inside than the shutter. When the magnetic card is further inserted in this way, the drive motor is started, and the magnetic card is fed into the inside by the feed roller like a conventional general magnetic card reader, and a predetermined operation is performed. It is assumed that the magnetic heads for reading and writing on the side of the magnetic card reader main body 13 are also arranged above and below the magnetic card passage.

As shown in FIG. 7, the upper magnetic head 16 is formed into two channels, channel A and channel B, and the lower magnetic head 17 is formed into two channels, channel A and channel B.
It is also formed into two channels, channel C and channel D. Then, the upper magnetic head 16
The gap part of channel A is placed in the first track 2 if the NTT standard magnetic card 1 is inserted correctly, and in the first track 41 if the ISO standard magnetic card 3 is inserted upside down. If the NTT standard magnetic card 1 is inserted correctly, the gap part of the channel B of the upper magnetic head 16 will be placed in the 1st track 2 of the opposing magnetic head 16.
When the ISO standard magnetic card 3 is inserted with its front and back reversed, the second track 42 faces each other. On the other hand, the lower magnetic head 1
The gap part of channel C of No. 7 is placed in the first track 2 if the NTT standard magnetic card 1 is inserted with the front side reversed, and in the first track 41 if the ISO standard magnetic card 3 is inserted correctly. The gap part of the channel D of the lower magnetic head 17 facing each other is an NTT standard magnetic card 1.
When the magnetic card 3 is inserted with the front side reversed, it faces the first track 2, and when the ISO standard magnetic card 3 is inserted correctly, it faces the second track 42. Furthermore, if the inserted magnetic card is a type 6 compatible with the NTT standard and the ISO standard, the gap portions of the two channels A and B of the upper magnetic head 16 both face the one track 2 of the NTT standard, ISO standard track 1 41
The gap portion of the channel C of the lower magnetic head 17 is opposed to the lower magnetic head 17, and the gap portion of the channel D of the lower magnetic head 17 is opposed to the second track 42 of the ISO standard. Here, the upper magnetic head 16 is assumed to be an NTT side detection head, and the lower magnetic head 17 is assumed to be an ISO side detection head. The density of each track of an ISO standard magnetic card is different from each other, and it is possible to determine what standard the inserted magnetic card is based on the output signals of each channel of the two magnetic heads arranged as described above. It is possible to determine whether the magnetic card has been inserted correctly. FIG. 8 shows an example of a circuit section including a card type discrimination circuit that performs such discrimination.

In FIG. 8, the detection signals of the A and B2 channels of the NTT side detection head 16 and the detection signals of the C and D2 channels of the ISO side detection head 17 are amplified by amplifiers 21, 22, 23, and 24, respectively, and then waveform shaped. The signals are shaped into rectangular waves by circuits 25 to 28 and input to discrimination circuits 29 and 30. These discrimination circuits 29 and 30 are charge up circuits 3 and 30, respectively.
1, 32, voltage comparison circuits 33, 34, and magnetic stripe detection circuits 35, 36, waveform shaping circuits 25 to 28, charge up circuits 31, 32, and voltage comparison circuits 33, 34 constitute an input signal frequency discrimination circuit. ing. The magnetic stripe detection circuits 35 and 36 are composed of counters, charge up circuits, etc., and detect the presence or absence of output signals from the waveform shaping circuits 26 and 27 to detect the magnetic head 1.
6 and 17 are reading information from the magnetic stripe. The charge up circuits 31 and 32 are charged up every time the output signals of the waveform shaping circuits 26 and 28 are input, respectively.
Each time the output signals of the waveform shaping circuits 25 and 27 are input, they are discharged and the output voltage changes depending on the difference in frequency between the two input signals. The voltage comparison circuits 33 and 34 compare the output voltages of the charge up circuits 31 and 32 with the set voltage to detect whether or not there is a difference in frequency between the two input signals.
Determine whether it is an NTT standard or an ISO standard. The control circuit 37 is composed of a microcomputer, etc., and is configured to detect the magnetic cards 1, 3, and 3 as shown in FIG.
6 is performed, and the aforementioned shutter 38, erroneous insertion display circuit 39, and card reader drive circuit 40 are controlled. That is, when a magnetic card is inserted from the card insertion slot, the output signals of the voltage comparison circuits 33 and 34 and the magnetic stripe detection circuits 35 and 36 are read.
Then, it is determined whether or not there are outputs from channels A and B of the magnetic head 16 based on the output signal of the magnetic stripe detection circuit 35, and if there are outputs from channels A and B, it is determined whether these outputs are the same or not by checking the voltage. The determination is made based on the output signal of the comparison circuit 33. If the outputs of channels A and B are the same, it is determined that the magnetic card was not inserted correctly, and if the outputs of channels A and B are the same, it is determined whether there is an output of channels C and D of the magnetic head 17. It is determined based on the output signal of the magnetic stripe detection circuit 36.
If there are no outputs from channels C and D, it is determined that the inserted magnetic card is NTT standard magnetic card 1, and if there are outputs from channels C and D, the voltage comparison circuit 34 determines whether these are the same. Judging from the output signal. If the outputs of channels C and D are the same, it is determined that the magnetic card was not inserted correctly. If the outputs of channels C and D are the same, the inserted magnetic card is an NTT/ISO standard common type magnetic card. It is determined that the value is 6. On the other hand, if there is no output from channels A and B, it is determined whether or not there is an output from channels C and D based on the output signal of the magnetic stripe detection circuit 36. If there is no output from channels C and D, the magnetic card is incorrect. It is determined that it was not inserted. Channel C,
If there is an output from channel D, it is determined whether these are the same or not based on the output signal of the voltage comparison circuit 34, and if the output from channels C and D is the same, it is determined that the magnetic card was not inserted correctly. However, if the outputs of channels C and D are not the same, it is determined that the inserted magnetic card is an ISO standard magnetic card 3. If it is determined that the magnetic card has not been inserted correctly, the incorrect insertion display circuit 3
9 to display the incorrect insertion of a magnetic card, and confirm that the inserted magnetic card is NTT standard magnetic card 1, ISO standard magnetic card 3, or NTT/ISO.
If it is determined that the card is one of the standard common type magnetic cards 6, the system is notified of the determination result and the solenoid drive circuit 44 is operated to shut down the shutter 3.
8 and the card reader drive circuit 40.
is operated to operate the main body 13. At this time, the main body 13 drives the magnetic card to read and process information from the track.

FIG. 10 specifically shows the discrimination circuit 29, and the discrimination circuit 30 has the same configuration. In Figure 10, 45 and 46 are buffers, 4
7 and 48 are capacitors and resistors that constitute the charge up circuit 31; 49 and 50 are capacitors;
1 to 54 are diodes, and 55 to 62 are comparators and resistors constituting a window comparator, and this window comparator is used as the voltage comparison circuit 33. Waveform shaping circuit 2
The rectangular wave outputs 5 and 26 are applied to the terminals via buffers 45 and 46 and capacitors 49 and 50. The charge-up circuit constituted by a capacitor 47 and a resistor 48 operates with voltage _V2 as a reference, and each time a rectangular wave that is active and low level is input to the terminal, it discharges a predetermined voltage through the diode 52, and when active and high level. Every time a rectangular wave is input to the terminal, the diode 5
3, the battery is charged to the predetermined voltage. The output voltage V ₃ of this charge up circuit is a set voltage V ₄ created by dividing the DC voltage V ₁ by resistors 57 to 60,
It is compared with V ₅ by comparators 55 and 56.

Currently, NTT standard magnetic cards are installed in card slot 19.
When inserted from the terminal, a square wave of the same frequency will be input to the terminal. Therefore, the charge-up circuit _alternately repeats charging and discharging, and as shown in _FIG . The output of
By remaining at a high level, the inserted magnetic card is determined to be NTT standard. Further, when an ISO standard magnetic card is inserted from the card insertion slot 19, a rectangular wave having a higher frequency than the terminal is input to the terminal. For this reason, the charge up circuit discharges more than it charges, and the output voltage V ₃ - drops as shown in FIG. When this output voltage V ₃ - becomes lower than the set voltage V ₅ , the output of the comparator 56 is inverted to a low level, and the inserted magnetic card is determined to be of ISO standard.
If a rectangular wave with a frequency lower than that of the terminal is input to the terminal (the gap part of the A channel of the magnetic head 16 is arranged corresponding to the second track 42 of the magnetic card 3 of the ISO standard, and the gap part of the B channel is When the charge-up circuit is arranged corresponding to the first track 41, etc., the charge-up circuit performs more charging than discharging, and the output voltage V ₃ rises as shown in FIG. 11, and when this exceeds the set voltage V ₄ The output of comparator 55 is inverted to low level.

In the discrimination circuit 29, if the output terminals of the comparators 55 and 56 are commonly connected to a DC power supply via a pull-up resistor 63 as shown in FIG. It is determined whether or not.

As described above, according to the present invention, there is provided a first magnetic card in which a plurality of narrow magnetic stripes having different recording densities are provided on the same surface, and a plurality of narrow magnetic stripes in the first magnetic card. In a magnetic card reader capable of selectively inserting a second magnetic card having one wide magnetic stripe positioned so as to overlap the magnetic stripe from the card insertion portion, a two-channel magnetic head that reads information from each magnetic stripe of the inserted first magnetic card and reads information from the same magnetic stripe of the second magnetic card inserted from the card insertion section; and a first waveform shaping circuit and a second waveform shaping circuit to which signals from each channel of the two channels of magnetic heads are respectively input, and each time the output signal of this second waveform shaping circuit is input. a charge pump circuit in which the output voltage increases and the output voltage decreases each time the output signal of the first waveform shaping circuit is input; and the first waveform shaping circuit compares the output voltage of the charge pump circuit with a set voltage. The first voltage comparison circuit determines whether the frequency of the input signal of the circuit and the frequency of the input signal of the second waveform shaping circuit are the same or different, so that the magnetic card inserted into the magnetic card reader is It becomes possible to determine whether the card is the first magnetic card or the second card, and it becomes possible to realize a magnetic card reader into which a plurality of types of magnetic cards can be inserted.

[Brief explanation of drawings]

Figures 1 and 2 are NTT standard magnetic cards.
A top view and a back view of a part of an ISO standard magnetic card, Figure 3 is a diagram showing the track position relationship between an NTT standard magnetic card and an ISO standard magnetic card, and Figure 4 is a diagram of the NTT/ISO standard common type. FIG. 5 is a perspective view showing an example of a magnetic card reader to which the present invention is applied; FIG. 6 is a front view showing a card gate portion of the magnetic card reader; FIG. 7 is a front view of the card gate. 8 is a block diagram showing the circuit section of the magnetic card reader, and FIG. 9 is a magnetic card discrimination control program of the control circuit in the circuit section. 10 is a circuit diagram specifically showing a part of the circuit section, FIG. 11 is a timing chart of a part of the circuit section, and FIG. 12 is a circuit diagram showing an example of the discrimination circuit. be. 25, 26... Waveform shaping circuit, 47... Capacitor, 48... Resistor, 55, 56... Comparator.

Claims (1)

[Claims] 1. A first magnetic card in which a plurality of narrow magnetic stripes having different recording densities are provided on the same surface; In a magnetic card reader capable of selectively inserting a second magnetic card having one wide magnetic stripe on the card insertion portion, the first magnetic card inserted from the card insertion portion; A magnetic head for two channels reads information from the same magnetic stripe for a second magnetic card inserted from the card insertion portion, and a magnetic head for these two channels reads information from each magnetic stripe for the second magnetic card inserted from the card insertion portion. a first waveform shaping circuit and a second waveform shaping circuit to which signals from each channel of the head are respectively input;
a charge pump circuit whose output voltage increases each time the output signal of the first waveform shaping circuit is inputted and whose output voltage decreases each time the output signal of the first waveform shaping circuit is inputted; a first voltage comparison circuit that compares with a set voltage and determines whether the frequency of the input signal of the first waveform shaping circuit and the frequency of the input signal of the second waveform shaping circuit are the same or different. A card type discrimination circuit for a magnetic card reader, characterized in that: