JP2004296058A - Magnetic recording method and device therefor, and device for discriminating coercive force of magnetic recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To write the magnetic information into a magnetic recording medium by a discriminated appropriate writing current which is discriminated for the magnetic recording medium. <P>SOLUTION: In this device, when a current value suitable for the write-in to the magnetic recording medium is obtained, the coercive force of the magnetic recording medium is obtained from a voltage at the read out time of the magnetic information written into the magnetic recording medium and the transportation amount of this magnetic recording medium, then the current value corresponded to this coercive force is obtained. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a magnetic recording method and apparatus for recording magnetic information on a magnetic recording medium such as a magnetic card, a form with a magnetic stripe, and a magnetic ticket with an appropriate current value, and a coercive force judging apparatus for the magnetic recording medium.
[0002]
[Prior art]
Normally, there are two types of magnetic cards with different types of magnetic stripes. One is a low coercive force magnetic card in which magnetic information is recorded by a magnetic head with a small write current. The other is a high coercive force magnetic card in which magnetic information is recorded by a magnetic head having a large write current.
[0003]
When a magnetic head writes magnetic information to a low coercive force magnetic card with a large write current, the magnetic information may not be sufficiently written. Therefore, when the magnetic information is read by the magnetic head, an appropriate read voltage cannot be detected, and the written information cannot be reproduced.
[0004]
A similar problem arises when a magnetic head writes magnetic information with a small write current to a high coercive force magnetic card.
[0005]
In order to determine whether the card is a high coercive force magnetic card or a low coercive force magnetic card, the following determination technology exists.
[0006]
(1) Writing is performed with a predetermined number of magnetic flux changes per predetermined length of the magnetic stripe while increasing the write current within a preset range while relatively moving the head. The written magnetic stripe is read by a read head. The voltage value and the current value from the read head are compared, and if the voltage value is within an allowable range, the current value in that case is selected. If the voltage value is not within the allowable range, the pre-selected range at the time of writing is changed, the steps of writing to the magnetic stripe again, reading it, and determining the write current value are repeated. Thereby, the coercive force of the magnetic stripe can be determined, and magnetic information can be written to the magnetic stripe with an appropriate current value (see Patent Document 1).
[0007]
(2) The coercive force of the magnetic recording medium is determined, and according to the result of the determination, the strength of the magnetic information added to the magnetic recording medium is changed while being adjusted in accordance with the coercive force of the magnetic recording medium. It is a recording device. There are two types of magnetic recording media used for this recording information: ordinary tickets and commuter passes. Information indicating whether the ticket is a high coercive force ticket or a low coercive force ticket is written in these tickets. By reading this with a read head, it is identified whether the inserted ticket is a high coercive force ticket or a low coercive force ticket. Based on this identification result, the magnetic recording is performed by setting the exciting current to a value suitable for the coercive force of the ticket (see Patent Document 2).
[0008]
The following is described as another method. Small plain tickets are high coercivity recording media. Large commuter passes are low coercivity recording media. Whether the conveyed ticket is a regular ticket or a commuter ticket is determined based on the size of the ticket. As a result of this determination, when it is determined that the ticket is a small ordinary ticket, information is written to the ticket with a high coercive force. On the other hand, if it is determined that the commuter pass is a large commuter pass, information is written to the ticket with low coercive force. Thus, magnetic recording is performed with a magnetic strength corresponding to the magnitude of the coercive force of the ticket.
[0009]
(3) The coercive force of the magnetic card used is read and determined by a magnetic card reader. In this case, in a magnetic card reader configured to reproduce or record magnetic information of a magnetic card inserted into a card insertion slot by a magnetic head, determining means for determining a coercive force of a data track for recording magnetic information. Is provided. Then, after recording test data on the data track of the captured magnetic card with a current corresponding to the low coercive force card, the test data is reproduced, and when the reproduced data matches the test data, it is determined that the card is a low coercive force card. This is a judgment (see Patent Document 3).
[0010]
(4) The coercive force of the magnetic card used is read and determined by a magnetic card reader. In this case, a magnetic card reader configured to reproduce or record magnetic information of a plurality of tracks formed on a magnetic card inserted from a card insertion slot by a plurality of magnetic heads provided corresponding to the plurality of tracks, Each of the magnetic heads records or erases data with a current having a different predetermined value, and includes a coercive force determining unit that determines three or more coercive forces of the data track by reproducing the recording or erasing result. is there. For example, reproduction is performed after erasing a first track with a current of a first value, and reproduction is performed after erasing a second track with a current of a second value. The coercive force of the magnetic card is determined based on the relationship between the resulting output level and the first and second values (see Patent Document 4).
[0011]
(5) This is a magnetic card coercive force determination method for determining the coercive force of a magnetic card to be used. In this case, the magnetic information formed on the low coercive force card or the high coercive force card inserted from the card insertion slot is reproduced or recorded by a magnetic head. After erasing the data on the inserted card with a current that can only erase the data on the magnetic force card, reproduce the data on that card and, if the data is in a destroyed state, determine the inserted card as a low coercive force card Is what you do. The destruction state of the data is determined by the number of times of magnetization reversal of the reproduced data or by not recognizing specific data (STX code) to be recorded on a predetermined card (see Patent Document 5). ).
[0012]
(6) It is possible to omit the operation of determining the magnetic coercive force, extend the life of the device, and avoid the danger of data corruption due to erroneous determination. Regardless of whether the magnetic card actually inserted is a high coercivity card or a low coercivity card, a high coercivity card is used so that desired magnetic information can be written satisfactorily without determining whether it is the coercivity card or the low coercivity card. After a recording operation using a write current, a re-recording operation using a low write current is performed to execute a recording operation on a magnetic card (see Patent Document 6).
[0013]
[Patent Document 1]
JP 2001-148101 A,
[Patent Document 2]
Japanese Patent Publication No. 4-38045,
[Patent Document 3]
JP-A-11-96506,
[Patent Document 4]
JP-A-11-328604,
[Patent Document 5]
JP 2000-155816 A,
[Patent Document 6]
JP-A-2001-118206.
[0014]
[Problems to be solved by the invention]
However, in Patent Literature 1, the magnetic card must be transported many times to determine an appropriate write current, and thus there is a problem that the determination process requires a long time.
[0015]
With respect to the other patent documents 2 to 6, it is possible to determine whether the type of the magnetic card is a high coercive force or a low coercive force. However, the variation of the coercive force of the low coercive force magnetic card is in a certain allowable range, whereas the coercive force of the high coercive force magnetic card often has a different coercive force. Therefore, an appropriate write current is often different for each high coercivity magnetic card.
[0016]
In these Patent Documents 2 to 6, even if the coercive force of the magnetic card is determined to be high coercive force or low coercive force, appropriate writing for writing to each magnetic card having a different coercive force is performed. Current cannot be measured.
[0017]
For this reason, it is desirable to find an appropriate write current according to each magnetic card. For example, it is conceivable to write magnetic information for determining coercive force on a magnetic card and read the written magnetic information to determine a write current suitable for the coercive force of the magnetic card.
[0018]
However, in this case, even if there is an abnormality in the coercive force determination magnetic information written on the magnetic card, the magnetic determination is performed as it is, and a normal coercive force cannot be obtained.
[0019]
SUMMARY OF THE INVENTION It is an object of the present invention to enable acquisition of magnetic information without any abnormality for determining coercive force from a magnetic recording medium. Then, an appropriate write current of the magnetic recording medium is obtained from the acquired magnetic information for determining coercive force without abnormality, and the magnetic information is written to the magnetic recording medium with the obtained appropriate write current. Another object of the present invention is to reduce the number of times of transport during writing to be smaller than the number of times of writing required for obtaining an appropriate writing current of the magnetic recording medium.
[0020]
[Means for Solving the Problems]
According to the present invention, while the magnetic recording medium is relatively moved in one direction with respect to the write head and the read head, the write head pre-writes the magnetic recording medium with a plurality of different current values, Is read by the read head, a proper value of a write current to the magnetic recording medium is determined based on the read result, and the write head performs a main write to the magnetic recording medium with the determined proper value. is there.
[0021]
Here, the magnetic recording medium is a medium having a magnetic recording surface such as a magnetic stripe that permits recording or reproduction of magnetic information.
[0022]
The write head generates a magnetic field by applying a current to the write head, and writes magnetic information on a magnetic recording surface of a magnetic recording medium that is in contact with the write head. When the write head moves in one direction relative to the magnetic recording medium, magnetic information is sequentially written on the magnetic recording surface of the magnetic recording medium. For example, writing is performed while moving the write head. Alternatively, writing is performed while the write head and the magnetic recording medium are relatively moved in one direction, such as writing while moving the magnetic recording medium.
[0023]
The read head generates a magnetic field when it moves on the magnetic recording surface of the magnetic recording medium, generates a voltage in the read head, and reads magnetic information from the magnetic recording surface of the magnetic recording medium based on a change in the voltage. When the write head moves relative to the magnetic recording medium in one direction, magnetic information is sequentially read from the magnetic recording surface of the magnetic recording medium. For example, reading is performed while moving the reading head. Alternatively, reading is performed while the read head and the magnetic recording medium are relatively moved in one direction, such as reading while moving the magnetic recording medium.
[0024]
These write head and read head may be provided side by side in the transport direction of the same transport path of the magnetic recording medium, or may be a single head having both functions capable of reading and writing.
[0025]
The pre-writing means writing magnetic information on the magnetic recording surface of the magnetic recording medium while changing the value of the write current of the write head.
[0026]
The main writing is to write magnetic information with a writing current suitable for the coercive force of the magnetic recording surface of the magnetic recording medium obtained from the result of the preliminary writing.
[0027]
The appropriate value is a write current value applied to a write head suitable for a coercive force that differs for each magnetic recording medium.
[0028]
According to this magnetic recording method, an appropriate value required for the actual writing is obtained from the result of the preliminary writing on the magnetic recording medium, and the actual writing is performed. The respective write operations of the preliminary write and the main write at this time are executed while the magnetic recording medium is relatively moved in one direction with respect to the write head.
[0029]
According to another aspect of the present invention, there is provided a magnetic recording apparatus including a write head for writing magnetic information on a magnetic recording medium, a read head for reading magnetic information from the magnetic recording medium, and control means for controlling these. A control unit configured to perform a preliminary write in which the write head performs preliminary write with a plurality of different current values on the magnetic recording medium while the magnetic recording medium relatively moves in one direction with respect to the write head and the read head; Processing, preliminary writing / reading processing for reading a preliminary writing result, which is the result of the preliminary writing, with the read head, and proper value obtaining processing for obtaining a proper value of a write current to the magnetic recording medium based on the preliminary writing result. And a main writing process for executing main writing on the magnetic recording medium with the write head based on the appropriate value.
[0030]
Here, the magnetic recording device can be constituted by a card reader or the like which reads magnetic information on a magnetic recording medium and writes the magnetic information on the magnetic recording medium.
[0031]
The appropriate value acquisition process calculates an appropriate value of a write current from an output value read by the read head. For example, a peak value of the amplitude of the waveform data read by the read head or a value close to the peak value is detected, and an appropriate value of the write current is acquired from the detected value.
[0032]
According to another aspect, the preliminary writing process is completed by an operation in which the magnetic recording medium passes through the write head once in one direction. The pre-reading process is also completed by the operation in which the magnetic recording medium passes through the read head once.
[0033]
If the read head and the write head are provided on the same transport path of the magnetic recording medium, the write processing and the read processing can be performed only by transporting the magnetic recording medium in one direction. Therefore, the coercive force of the magnetic recording medium can be obtained with a small number of conveyances.
[0034]
In another aspect, a transport unit that transports the magnetic recording medium, a transport amount detecting unit that detects a transport amount of the magnetic recording medium, and a transport unit that transports the magnetic recording medium in one direction while being transported by the transport unit. A write head for writing magnetic information to the magnetic recording medium at a plurality of different current values; and the magnetic recording medium, wherein the magnetic information is written on the magnetic recording medium by the write head and then conveyed by the conveying means. A magnetic recording apparatus comprising: a read head for reading magnetic information of a medium; and determination means for determining a coercive force of the magnetic recording medium based on a voltage read by the read head and a transport amount of the magnetic recording medium at the time of reading. It is a coercive force determination device for a medium.
[0035]
The transport means constitutes a transport path of the magnetic recording medium by disposing transport members such as a transport roller and a transport belt that rotate upon receiving a rotational driving force from a motor in the transport direction. Then, the magnetic recording medium guided here is moved in the loading direction or the returning direction.
[0036]
Further, a write head and a read head are arranged in this transport path, and magnetic information is written on a magnetic recording medium passing therethrough. Also, the magnetic information of the magnetic recording medium passing therethrough is read.
[0037]
The transport amount corresponds to a transport distance or a transport time when the magnetic recording medium is transported by driving the transport unit with a motor or the like.
[0038]
The transport amount detecting means detects the transport amount when the magnetic recording medium is transported. For example, there is a proportional relationship between the number of rotations of a motor serving as a driving source of the transporting means and the moving distance of the magnetic recording medium. For this reason, the number of rotations of the motor may be detected, or the moving distance of the magnetic recording medium may be detected. Further, when the magnetic recording medium is transported at a constant speed, the moving distance of the magnetic recording medium is proportional to the time required for the movement. Therefore, the moving distance of the magnetic recording medium may be detected, or the moving time thereof may be detected.
[0039]
When the magnetic information of the magnetic recording medium written with a plurality of different current values is read, the determination unit determines a transport amount of the magnetic recording medium and a change in a voltage obtained from the read head according to the transport amount. The coercive force of the magnetic recording medium is determined.
[0040]
According to another aspect, the write position and the read position of the magnetic information on the magnetic recording medium are measured from the voltage when reading the magnetic information written on the magnetic recording medium and the transport amount of the magnetic recording medium. . Then, the coercive force of the magnetic recording medium is obtained by measuring the magnetic recording position. In particular, instead of transporting the magnetic recording medium in a different manner each time the magnetic recording medium is transported in one direction when the magnetic recording medium is transported, the write head may feed the magnetic recording medium with a plurality of different current values such as a high current and a low current. Write a wide range of magnetic information. For this reason, the number of transports for writing magnetic information at the time of preliminary writing is only one.
[0041]
According to another aspect of the invention, a transport unit that transports the magnetic recording medium, a transport amount detection unit that detects a transport amount of the magnetic recording medium, and writes magnetic information on the magnetic recording medium that is being transported by the transport unit A write head, write current waveform storage means for storing a waveform that changes in accordance with the carry amount of the write current value of the write head, and the writing in accordance with the write current value stored in the write current waveform storage means. Write current changing means for changing a write current of a head, and a read head for reading magnetic information of the magnetic recording medium being conveyed by the conveying means after writing magnetic information on the magnetic recording medium by the write head And the voltage read by the read head, the transport amount of the magnetic recording medium at the time of reading, and the write current stored in the write current waveform storage means. Determining means for determining the coercive force of the magnetic recording medium according to the time change of the magnetic recording medium, wherein the write current changing means changes the same waveform by repeating the same waveform a plurality of times. It is characterized by doing.
[0042]
The waveform that changes according to the transport distance is a waveform that indicates the current value at the time of writing as the transport distance elapses. In addition to this waveform, the current value at the time of writing may be created by a function that represents the current value over time. Further, the transport time may be used instead of the transport distance.
[0043]
According to another aspect, when writing with a write head, information of a plurality of waveforms is obtained by changing the write current and repeating the same waveform a plurality of times. Therefore, by comparing a plurality of acquired waveforms, it is possible to determine the suitability of each waveform because the same waveform is written. For example, if two of the three waveforms are the same and one waveform is different, one waveform is recognized as a defective abnormal waveform. As a result, the coercive force can be determined from a plurality of waveforms excluding the abnormal waveform.
[0044]
In another aspect of the invention, the writing head does not write for the time for separating the plurality of the same waveforms during the repetition of the same waveform during the transport of the magnetic recording medium.
[0045]
A transport time may be used instead of the distance, and a plurality of waveforms may be separated by the transport time.
[0046]
In this case, since there is an unwritten portion between the waveforms to separate the two waveforms, each of the repeatedly written waveforms can be distinguished.
[0047]
In another aspect of the present invention, during the transport of the magnetic recording medium, the write current of the write head is set to a reference value for a time period during which the write current changing means creates another waveform at the reference position during the repetition of the same waveform. It is characterized by maintaining the size of the waveform to be the position.
[0048]
In this case, another waveform different from the waveform is formed between the waveforms. This serves as a mark, and by providing the mark, a plurality of waveforms can be distinguished. Further, since this mark can be set at a reference position for positioning the waveform, the transport amount of the magnetic recording medium can be obtained.
[0049]
According to another aspect of the present invention, the write current changing means alternately repeats the write current of the write head between output and stop at predetermined intervals while the magnetic recording medium is being conveyed.
[0050]
In this case, the write stop portion is a mark without a waveform, which is a reference position for measuring the position of the waveform. In particular, since the waveform and the mark can be alternately provided at short time intervals, even if any waveform disappears, it can be recognized. Therefore, the transport position of the magnetic recording medium corresponding to the write position of the medium can be specified.
[0051]
According to another aspect of the invention, the write current changing unit increases the write current of the write head in a stepwise manner while the magnetic recording medium is being conveyed, and varies the time for maintaining the current value each time the write current is changed. And
[0052]
In this case, the time for which the write current value is increased stepwisely is different. For this reason, each of the write waveforms written step by step is a mark due to the difference in the maintenance time.
[0053]
In another aspect, a transport unit that transports a magnetic recording medium, a transport amount detecting unit that detects a transport amount of the magnetic recording medium, and a write operation that writes magnetic information on the magnetic recording medium that is transported by the transport unit A head, a write current waveform storage means for storing a waveform that changes in accordance with a conveyance distance of a write current value of the write head, and a write current value stored in the write current waveform storage means. Write current changing means for changing a write current, and a read head for reading magnetic information of the magnetic recording medium carried by the magnetic recording medium after writing magnetic information on the magnetic recording medium by the write head. The voltage read by the read head, the transport amount of the magnetic recording medium at the time of reading, and the write stored in the write current waveform storage means. Determining means for determining a coercive force of the magnetic recording medium in accordance with a time change of the flow value, wherein a coercive force determining apparatus for the magnetic recording medium comprises: At both ends, the determination means determines the transport amount of the magnetic recording medium when the reading is performed by the reading head, based on a position where the read voltage value read is large.
[0054]
Both ends of the waveform reading area are from the write start position to the write end position for each waveform read by the read head.
[0055]
In this case, the position where the read voltage value is large is set as the reference position. Therefore, the waveform itself can have a reference position.
[0056]
In another aspect, a write head that writes magnetic information on a magnetic recording medium, a read head that reads magnetic information on a magnetic recording medium, a transport unit that transports the write head and the read head, Transport amount detecting means for detecting the transport amount of the read head; current changing means for changing the drive current of the write head during transport in one direction in which the write head is transported by the transport means; After writing magnetic information on a magnetic recording medium, the read head is transported by the transport means, read control means for reading the magnetic information of the magnetic recording medium, and a value read by the read head by the read control means, Determining means for determining the coercive force of the magnetic recording medium based on the transport amount of the read head at the time of reading. Characterized in that it is a coercive force determining device for a recording medium.
[0057]
In this case, the magnetic information is recorded or reproduced on the magnetic recording medium while the magnetic recording medium is stationary and the write head and the read head are transported.
[0058]
According to another aspect of the invention, a transport unit that relatively moves the magnetic recording medium with respect to the write head and the read head, a transport amount detection unit that detects an amount of movement by the transport unit, and the transport unit A write current changing means for changing a write current of the magnetic head during movement of the magnetic recording medium in one direction which is moving relative to the magnetic recording medium, after writing magnetic information on the magnetic recording medium by the write head; Reading the magnetic information of the magnetic recording medium relatively moving with respect to the read head with the read head, and detecting the magnetic information of the magnetic recording medium based on the voltage read by the read head and the amount of movement when reading. The present invention is characterized in that the device is a coercive force judging device for a magnetic recording medium, comprising a judging means for judging magnetic force.
[0059]
In this case, when recording or reproducing magnetic information on the magnetic recording medium, recording or reproducing may be performed while moving the magnetic recording medium to the position of the stationary head, and the head may be moved to the position of the stationary magnetic recording medium. Recording or reproduction may be performed while moving. Further, the magnetic processing may be performed while moving not only one of the magnetic recording medium and the head but also both of them.
[0060]
According to another aspect of the present invention, in the above-described apparatus for determining coercive force of a magnetic recording medium, the read head reads magnetic information of the magnetic recording medium in advance, and stores the magnetic information of the magnetic recording medium read in advance. Means, and after the determination by the determination means, writes the magnetic information stored in the magnetic information storage means to the magnetic recording medium with a current corresponding to the coercive force determined by the determination means. It is characterized in that
[0061]
In this case, when the magnetic recording medium is transported in one direction, the magnetic information stored in the medium is read to determine the coercive force. Then, writing is performed with a current corresponding to the coercive force.
[0062]
According to another aspect of the invention, a transport unit that relatively moves the magnetic recording medium with respect to the write head and the read head, a transport amount detection unit that detects an amount of movement by the transport unit, and the transport unit Write current changing means for changing the write current of the magnetic head during one-way conveyance of the magnetic recording medium which is relatively moving; and a write position for detecting a position where the write head has written on the magnetic recording medium. Detecting means for writing magnetic information on the magnetic recording medium by the write head, and then reading magnetic information of the magnetic recording medium moving relative to the read head with the read head; Determining means for determining the coercive force of the magnetic recording medium based on the read voltage, the amount of movement when reading, and the written position; Characterized in that the a coercive force determination device for a magnetic recording medium.
[0063]
The write position detecting means can be realized by counting the number of bits of the write information.
[0064]
In this case, when recording or reproducing the magnetic information on the magnetic recording medium, the magnetic processing may be performed while moving one or both of the magnetic recording medium and the head (write head, read head). Further, since the position where data is written on the magnetic recording medium is detected, the coercive force of the magnetic recording medium can be obtained from the written position. As a result, magnetic information can be written by finding an appropriate write current value suitable for the coercive force of the magnetic recording medium.
[0065]
【The invention's effect】
According to the present invention, an appropriate value of the write current to the magnetic recording medium can be obtained, and the number of times of conveyance is reduced.
[0066]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings.
[0067]
[First Embodiment]
The drawing shows a card reader for writing and reading magnetic information on a magnetic card.
[0068]
FIG. 1 shows a control circuit block diagram of the card reader 30. The card reader 30 includes a motor encoder 31, a CPU 32, a D / A converter 33, a current control circuit 34, a write head 35, a read head 36, an amplifier 37, an A / D converter 38, a RAM 39 , ROM 40.
[0069]
The motor encoder 31 is an encoder provided for a motor of a transport system. The motor encoder 31 detects the number of pulses when the motor rotates and outputs with a photo sensor through a slit of a disk provided on the motor shaft. Thus, the CPU 32 calculates that the motor has been driven and the number of rotations at that time.
[0070]
The CPU 32 executes a control process of a device connected to the CPU 32 according to a program stored in the ROM 40. When writing magnetic information to a magnetic card according to the program, an appropriate write current value required for the actual writing is obtained from the result of preliminary writing to the magnetic card, and the actual writing is performed.
[0071]
First, in the case of preliminary writing, the writing current is increased stepwise, and preliminary writing is performed with a plurality of different current values of a high current and a low current at that time. The plurality of different current values are stored in the ROM 40 as preliminary data. Then, when reading the preliminary data that has been preliminarily written, the CPU 32 obtains an appropriate value of a write current suitable for each coercive force of each magnetic card from the preliminary write result. The obtained proper value is set as a current value for the main writing, and this current value is stored in the ROM 40 as main data. Then, actual writing is performed using the current value of the actual data.
[0072]
The D / A converter 33 converts digital data into an analog signal. At this time, the D / A converter 33 sets a write current of magnetic information (preliminary data and main data) to be written to the magnetic card C. Specifically, a process of stepwise increasing the current supplied to the current control circuit 34 is performed based on digital data set to increase the current value stepwise.
[0073]
The current control circuit 34 outputs the write data commanded by the CPU 32 to the write head 35 with the current value supplied from the D / A converter 33.
The write head 35 writes the write data at the current value on the magnetic stripe St (see FIG. 3) of the magnetic card C by changing the magnetic flux.
[0074]
The read head 36 reads a voltage value (output value) obtained when reading data written on the magnetic stripe St of the magnetic card C.
[0075]
The amplifier 37 outputs a voltage value read by the read head 36 to an A / D converter 38.
[0076]
The A / D converter 38 converts an analog signal into digital data. The A / D converter 38 reads the voltage value as a waveform and outputs the voltage value as waveform data.
The RAM 39 temporarily stores data and the like necessary for the control processing by the CPU 32.
[0077]
The ROM 40 stores necessary programs such as an appropriate current value calculation program. The appropriate current value determination program has initial current value (lowest current value) data, predetermined maximum current value (highest current value) data, and spare data. Further, in order to calculate an appropriate write current value, preliminary data is transmitted to the current control circuit 34. Further, the current value is increased stepwise from the lowest current value data to the highest current value data, and a preliminary write process of transmitting the current value from the D / A converter 33 to the current control circuit 34 is executed. At this time, the magnetic card C is moved by a motor having the motor encoder 31, and control is performed so that the preliminary data having the different current values is sequentially written.
[0078]
When the preliminary write processing is completed, the voltage value acquired from the read head 36 via the amplifier 37 is converted into waveform data in the A / D converter 38. The peak value of the amplitude of the converted waveform data is determined, and the waveform data slightly before the peak value is set as an appropriate value as the write current value of the data.
[0079]
In this case, the reason why the appropriate write current value is set slightly before the peak value of the amplitude is that the output voltage becomes saturated after the peak value of the amplitude (see FIG. 4). Therefore, the corresponding position is set to an appropriate write current value before the output voltage is saturated.
[0080]
With the above configuration, the CPU 32 can write the spare data and the main data on the magnetic stripe of the magnetic card, read the spare data and the main data, and read the output value.
[0081]
Next, the processing operation of the card reader 30 will be described with reference to the flowchart of FIG. 2 and the illustration of the magnetic processing operation of FIG.
The CPU 32 starts an appropriate current value determining program. Then, the minimum current value is set and the transport of the magnetic card C is started (step n1).
[0082]
As shown in FIG. 3A, the CPU 32 uses the write head 35 to write the spare data on the magnetic stripe St of the magnetic card C with the current value (digital data) (step n2).
[0083]
Then, the current value is increased by a fixed amount (step n3).
[0084]
If the increased current value is less than the maximum current value, the process returns to step n2, and the writing of the preliminary data is repeated until the increased current value reaches the maximum current value (step n4).
[0085]
By repeating this, as shown in FIG. 3B, the current value is increased stepwise to write the preliminary data. In the drawing, the chart indicated by the imaginary line represents a state in which the horizontal axis is time t and the vertical axis is current intensity mA, and the writing is repeated while increasing the current.
[0086]
When the maximum current value is reached, the written preliminary data is read by the read head 36 (step n5).
[0087]
At this time, the read head 36 reads the voltage value of the preliminary data from the magnetic stripe St, and can obtain the waveform data of the voltage as shown by the imaginary line in FIG. In the chart showing the waveform data, the horizontal axis represents the current intensity mA and the vertical axis represents the voltage intensity mV, and represents a change in the voltage value output from the magnetic stripe St.
[0088]
The waveform data obtained by reading the preliminary data is converted into digital data by the A / D converter 38, and the peak value of the amplitude is detected (step n6).
[0089]
Then, a current value corresponding to a position slightly before this peak value is set as a write current value (step n7).
[0090]
The CPU 32 terminates the appropriate current value determining program, and performs the actual writing of the main data with the appropriate current value on the magnetic stripe St of the magnetic card C with the calculated (acquired) appropriate current value (step n8).
[0091]
With the above operation, as shown in the chart of FIG. 5 current values P1 to P5 can be set.
That is,
For the magnetic card of the first waveform data A1, the first current value P1 (about 215 mA),
For the magnetic card of the second waveform data A2, the second current value P2 (about 89 mA),
For the magnetic card of the third waveform data A3, the third current value P3 (about 72 mA),
For the magnetic card of the fourth waveform data A4, the fourth current value P4 (about 18 mA),
For the magnetic card of the fifth waveform data A5, the fifth current value P5 (about 17 mA),
Is set, and the actual writing can be executed with an appropriate current value.
[0092]
In this case, in the case of the first to third waveform data A1 to A3, the magnetic card C has a high coercive force indicating a high write current value when the output voltage is high. On the other hand, in the case of the fourth and fifth waveform data A4 and A5, the magnetic card C has a low coercive force indicating a low write current value when the output voltage is high.
[0093]
However, a saturation state occurs after the current values P1 to P5. Therefore, in order to obtain writing safety (stability), each current value at the time of saturation may be set as a current value suitable for writing.
[0094]
In the case of the high coercive force magnetic card shown in the first to third waveform data A1 to A3, in order to further enhance the writing safety (stability), a current value equal to or higher than the saturation value (for example, the saturation It is also possible to set the current value to twice the current value.
[0095]
In this manner, the card reader 30 can search for an appropriate current value for any magnetic card C, such as a high coercive force magnetic card or a low coercive force magnetic card, and execute the actual writing.
[0096]
In particular, the writing of the preliminary data is completed by the operation in which the magnetic card C passes through the write head 35 once in one direction. The reading of the spare data is also completed by the operation in which the magnetic card C passes through the read head 36 once.
[0097]
In the above-described embodiment, the writing and reading of the preliminary data are executed by the operation of passing the magnetic card C once, but the present invention is not limited to this. For example, in a card reader that reciprocates the magnetic card C, it is set so that the operation of passing the magnetic card C once writes the preliminary data, and the operation of passing the magnetic card C in the returning direction reads the preliminary data. May be. In this case, the spare data can be written to the entire magnetic stripe St without depending on the interval between the write head 35 and the read head 36.
[0098]
[Second embodiment]
FIG. 5 shows an outline of a cross section of a card reader 51 provided with a coercive force determination device for a magnetic card.
The card reader 51 has a card insertion port 53 for inserting or returning the magnetic card C on the front surface of the main body 52. A card transport path 54 for transporting the inserted magnetic card C in the insertion direction or in the return direction is provided inside the card insertion port 53 and connected to the inside.
[0099]
The above-described card transport path 54 is provided with a pair of upper and lower front transport rollers R1, R2, a magnetic head 55, and a pair of upper and lower rear transport rollers R3, R4 from the card insertion slot 53 to the inner back. Further, first to third detection sensors S1 to S3 are arranged at these three positions.
[0100]
Of the transport rollers R1 to R4, the rotation shaft of one of the transport rollers facing up and down is connected to receive a rotational driving force from a motor (not shown). Then, as the motor rotates, the transport roller rotates.
[0101]
As a result, the magnetic card C guided here is sandwiched between the upper and lower front transport rollers R1, R2 and the rear transport rollers R3, R4 and transported in the take-in direction or the return direction. The magnetic card C is transported at a constant speed by rotating the motor and rotating the transport roller.
[0102]
When the magnetic card C is conveyed and the magnetic card C comes into contact with the magnetic head 55, the magnetic card C is magnetically written or read. One magnetic head 55 is provided in the card transport path 54, and this one is used to write and read the magnetic card C. Further, the position of the magnetic card C on the card transport path 54 is detected by the first to third detection sensors S1 to S3.
[0103]
FIG. 6 shows a control block diagram of the card reader 51.
The card reader 51 includes a CPU 61, a memory 62, a magnetic writing control unit 63, a magnetic reading control unit 64, a magnetic head 55, a motor control unit 65, a motor M, a rotary encoder 66, a card position detection A portion 67 and first to third detection sensors S1 to S3 are provided.
[0104]
The CPU 61 controls devices connected to the CPU 61 according to a program stored in the memory 62.
[0105]
The memory 62 stores a program and data for determining an appropriate current value of a write current value suitable for a coercive force different for each magnetic card.
[0106]
The magnetic writing control section 63 includes a D / A converter. The D / A converter converts digital data of the write information received from the CPU 61 into an analog signal. Then, the magnetic write control unit 63 performs control to output a current value corresponding to the analog signal at a constant cycle.
[0107]
The magnetic read control unit 64 performs read control for each read track from the magnetic stripe. The signal received from the magnetic head 55 is amplified. Then, the analog signal is converted into digital data by the A / D converter. Then, the converted digital data is transmitted to the CPU 61.
[0108]
The magnetic head 55 generates a magnetic field when a current is applied. By changing the applied current, magnetic information is written on the magnetic card C that is in contact with the magnetic head 55. By transporting the magnetic card C to the magnetic head 55, a large amount of information is sequentially written.
[0109]
Then, the magnetic card C on which the magnetic information is written is brought into contact with the magnetic head and conveyed, thereby generating a magnetic field. A voltage is generated in the magnetic head 55 in response to a change in the magnetic field. The magnetic head 55 reads the information recorded on the magnetic card by detecting the change in the voltage.
[0110]
By the way, at the time of the above-mentioned writing, an appropriate writing current value required for the actual writing is obtained from the result of the preliminary writing to the magnetic card C, and the actual writing is performed. First, in the case of preliminary writing, the writing current is increased stepwise, and preliminary writing is performed with a plurality of different current values of a high current and a low current at that time. The plurality of different current values are stored in the memory 62 as preliminary data. Then, when the pre-written spare data is read from the magnetic card C, the CPU 61 obtains an appropriate value of the write current suitable for each coercive force for each magnetic card from the preliminary write result. The obtained proper value is set as a current value for the main writing, and this current value is stored in the memory 62 as main data. Then, actual writing is performed using the current value of the actual data.
[0111]
The motor control unit 65 receives a drive signal or a stop signal from the CPU 61 and controls the motor M to rotate at a constant rotation speed. Further, by rotating the motor M in the normal rotation direction or the reverse rotation direction, the magnetic card C is transported in the card transport path 54 in the loading direction or the returning direction.
[0112]
The rotary encoder 66 calculates the number of rotations by detecting the number of pulses with a photosensor from a slit of a disk provided on the motor shaft of the motor M.
[0113]
The card position detection section 67 acquires each detected signal from the first to third detection sensors S1 to S3 disposed on the card transport path 54. Then, the position where the magnetic card C is present is output to the CPU 61.
[0114]
The CPU 61 executes a process of writing spare data in which the current value increases stepwise from the lowest current value to the highest current value according to the program in the memory 62. At this time, control is performed such that the spare data is sequentially written while the magnetic card C is moved in the taking-in direction by the motor M.
[0115]
After the preliminary writing, the prewritten magnetic information is read from the magnetic card C by the magnetic head 55. Then, the voltage value received by the magnetic read controller 64 from the magnetic head 55 is received as waveform data. The waveform peak of the waveform data is determined, and a current value suitable for writing the data is set with an appropriate value slightly before the waveform peak.
[0116]
In this case, the reason why the appropriate write current value is set slightly before the peak value of the amplitude is that the output voltage becomes saturated after the peak value of the amplitude (see FIG. 4). In order to prevent the output voltage from being saturated, the corresponding position is set to an appropriate write current value before the output voltage is saturated.
[0117]
Next, a case where an appropriate write current value is obtained from the result of determining the coercive force of the magnetic card will be described.
[0118]
The CPU 61 controls writing of magnetic information with a plurality of different current values via the magnetic head 55 to the magnetic card C being conveyed in one direction on the card conveyance path 54 during the conveyance in one direction. After writing the magnetic information, the magnetic head 55 reads the magnetic information of the magnetic card C being transported on the card transport path 54. The coercive force of the magnetic card C is determined based on the read voltage and the transport amount of the magnetic card C at the time of reading. Then, a current value corresponding to the coercive force is set as a current value suitable for writing.
[0119]
In particular, while transporting the magnetic card C in one direction, the magnetic head 55 writes magnetic information on the magnetic card C with a plurality of different current values that are stepwise raised. Then, preliminary data can be written only by passing once in one direction. For this reason, the number of times of conveyance when writing while changing the write current value from a certain value to another value is sufficient. Further, whether or not the information has been normally written can be confirmed by reading with the magnetic head 55 when the magnetic card C is transported in the return direction, based on the current value at the time of writing.
[0120]
In detecting the write position of the magnetic card C, the pulse command cycle from the CPU 61 to the motor M and the write command cycle from the CPU 61 to the magnetic head 55 are in a proportional relationship. Thus, by reading the write data from the magnetic card and counting the number of bits, the write position corresponding to the written magnetic information on the magnetic card can be known. Therefore, the detection of the position where the magnetic information is written on the magnetic card C can be obtained by counting the write command cycle for the motor M.
[0121]
As another means for detecting the write position of the magnetic card C, the number of bits of information to be written may be counted. Alternatively, the rotation amount of a rotary encoder that outputs the rotation amount of the motor M may be measured.
[0122]
Further, a roller connected to a rotary encoder may be brought into contact with the magnetic card C and the amount of rotation thereof may be measured. The reason why either method may be used is that these measured amounts are proportional to the carry amount when the magnetic card C is carried.
[0123]
On the other hand, when reading magnetic information from the magnetic card C, the reading position can be detected by measuring the rotation amount of a rotary encoder that outputs the rotation amount of the motor M. Alternatively, a roller of a rotary encoder may be brought into contact with the magnetic card C and the amount of rotation thereof may be measured.
[0124]
Next, the main processing operation of the card reader 51 will be described with reference to the diagram showing the position where the magnetic card C is conveyed in FIG. 7 and a flowchart. FIG. 7 shows the order of each process on the left side. The cross-sectional view of each card reader 51 on the right side shows the position of the magnetic card C when each processing is completed. The arrow near the magnetic card C indicates the direction in which the magnetic card C moves in the next process.
[0125]
The motor control unit 65 drives the motor M to take in the magnetic card C inserted into the card insertion slot 53 of the card reader 51. Then, the magnetic head 55 reads magnetic information recorded on the magnetic stripe of the magnetic card C being conveyed in the card taking-in direction. The read magnetic information is stored as initial data in the memory 62 (step n11).
[0126]
After reading, the magnetic card C is transported in the return direction. At the time of contact with the magnetic head 55, a current for data erasing is applied to the magnetic head 55 to erase the magnetic information of the magnetic card C. As a result, the magnetic card enters a standby state for preliminary writing (step n12).
[0127]
When the magnetic information of the magnetic card C is erased, the magnetic card C is transported again in the loading direction. Then, preliminary writing is performed by the magnetic head 55 during this transport. This preliminary writing is writing (step n13) in which the current value is changed stepwise from a low current value to a high current value (see FIGS. 8 and 9 described later).
[0128]
After the preliminary writing in which the current value is changed stepwise, the magnetic card C is transported in the returning direction, and the magnetic information preliminarily written on the magnetic card C is read by the magnetic head 55. At this time, the number of encoder pulses is counted simultaneously. Thereby, the rotation speed of the motor M is obtained. Since the number of rotations of the motor M and the moving distance of the magnetic card C are in a proportional relationship, the moving distance of the magnetic card C can be obtained from the number of encoder pulses. By obtaining the moving distance, the correspondence between the preliminary write position and the written data is obtained (step n14).
[0129]
After reading the preliminary write information, the magnetic card returns to the original position on the card insertion slot 53 side and waits for the next main write. Then, the CPU 61 detects an appropriate write current value from the read magnetic information (see FIG. 10 described later) (step n15).
[0130]
From this detection result, the CPU 61 sets an appropriate write current value (step n16).
[0131]
When an appropriate write current value is set, the CPU 61 proceeds to the main write and conveys the magnetic card C in the take-in direction. While being conveyed, the magnetic information is permanently written to the magnetic card C by the magnetic head 55 at a write current value suitable for writing. The magnetic information written here is the initial data read in step n11. Alternatively, predetermined information stored in the memory 62 may be written on a magnetic card. Thus, the actual writing is completed (step n17).
[0132]
When the main writing is completed, the magnetic card C on which the main writing is performed is transported in the return direction. The magnetic head 55 reads the magnetic information of the magnetic card C during the transport in the return direction. At this time, it is confirmed whether the magnetic information is normally magnetically recorded on the magnetic card C (step n18).
[0133]
When it is confirmed that the read data matches the written data, the magnetic card C is returned to the card insertion port 53 (step n19). The user can take out the magnetic card C from the insertion slot of the card reader 51. Thereby, the main processing operation of one magnetic card C in the card reader 51 ends.
[0134]
Next, an example of preliminary writing in which the current value in step n13 is changed stepwise will be described.
[0135]
The memory 62 stores a waveform that changes according to the transport distance of the write current value of the magnetic head 55. Then, the write current value applied to the magnetic head 55 is changed according to the write current value stored in the memory 62. In this case, the waveform that changes according to the transport distance is a waveform that represents the state of change in the current value at the time of writing in a stepwise manner as the transport distance changes.
[0136]
In this case, the waveform is not one for one magnetic stripe, but the same waveform repeated for one magnetic stripe a plurality of times. For example, as shown in FIG. 8, the same waveform is repeated three times on a magnetic stripe formed in the longitudinal direction of the magnetic card C. According to this waveform, the current value of the magnetic head 55 is changed, and magnetic information is written on the magnetic stripe. Thereby, first to third waveforms W1 to W3 are obtained according to the writing order. As a result, by comparing each of the three acquired waveforms W1 to W3, since the same waveform is written, even if any of the waveforms has an abnormality, it is possible to determine whether the waveform is appropriate.
[0137]
For example, if two waveforms are the same and one waveform is different among three waveforms, one waveform is recognized as a defective abnormal waveform. As a result, the coercive force can be determined from the waveform excluding the abnormal waveform. The cause of the waveform abnormality at this time is caused by a scratch on the magnetic stripe surface or by adhesion of dust.
[0138]
In addition to the above-described waveforms, the current value at the time of writing can be created by a function representing the change in the transport distance. Further, the transport time can be used instead of the transport distance.
[0139]
In addition, when repeatedly writing the three waveforms W1 to W3, a write stop unit 81 is formed which does not write for a short time to separate the waveforms before writing the waveforms. Thus, the write stop unit 81 is interposed between the waveforms. Therefore, since the write stop unit 81 can be set at the reference position of each of the waveforms W1 to W3, each of the repeatedly written waveforms W1 to W3 can be clearly distinguished.
[0140]
Next, the operation of pre-writing by changing the current value stepwise will be described with reference to the flowchart of FIG.
[0141]
The CPU 61 first drives the motor M to perform preliminary writing on the magnetic card C. As a result, the magnetic card is transported at a constant speed (step n21).
[0142]
During this conveyance, before writing the waveform, the CPU 61 temporarily suspends the write current of the magnetic head 55 via the magnetic write control unit 63, and waits for the write operation for the time during which the write stop unit 81 can be obtained (step n22).
[0143]
After the elapse of the standby time, the magnetic write control unit 63 first sets the writing with the lowest current value (step n23).
[0144]
With this minimum current value, one bit of information is written (step n24).
[0145]
Then, it is determined whether or not predetermined bits have been written (step n25). If it is determined that the data has not been written for the predetermined bit, the data is written again for one bit again (step n24). If it is determined that a predetermined number of bits have been written, the next current value is set in order to write the current value stepwise (step n26). Then, it is determined whether the writing of the first waveform is completed (step n27). If the writing of the first waveform is not completed, one bit is written again (step n24).
[0146]
Until the writing is completed with the current value based on the first first waveform W1 (see FIG. 8), the writing operation of increasing the current value for each bit is repeatedly performed stepwise (steps n24 to n24). n27).
[0147]
Thereafter, when it is determined that the writing based on the first first waveform W1 has been completed (step n27), the process proceeds to writing based on the next waveform. Also in this case, first, the writing operation is made to wait for the time of the writing stop unit 81. Thereafter, when the magnetic card C is conveyed by the distance of the write stop unit 81, the write from the minimum current value in step n22 and thereafter is executed. In this way, information is written bit by bit with a current value based on the next second waveform W2 (see FIG. 8). After writing based on the second waveform W2, the same procedure is repeated to write information bit by bit with a current value based on the third waveform W3 (see FIG. 8) (step n28).
[0148]
When the writing is completed, the writing current is stopped, the rotation of the motor M is stopped, the conveyance of the magnetic card C is stopped, and the preliminary writing is completed (step n29).
[0149]
In this way, information is written with current values based on all the waveforms W1 to W3. While the magnetic card C is conveyed in one direction from the starting end to the end of the card conveying path 54, all three waveforms W1 to W3 are written.
[0150]
Next, an operation of detecting an appropriate write current value required for actual writing will be described with reference to a flowchart of FIG.
[0151]
The magnetic card C, which has been moved to the end side of the card transport path 54 after the completion of the preliminary writing, is transported on the card transport path 54 in the return direction. While being conveyed in this manner, the magnetic card C contacts the magnetic head 55, and the voltage generated in the magnetic head 55 is read based on the magnetic information written on the magnetic card C. The maximum output voltage is searched for from the voltage value at the time of reading (step n31).
[0152]
Then, the card position of the magnetic card C is calculated from the motor signal (encoder pulse) when the maximum output voltage is obtained (step n32).
[0153]
At the obtained card position, a current value of information written at the time of preliminary writing is obtained. This is an appropriate current value for actual writing to the magnetic card C. (Step n33).
[0154]
Next, the case where the card position is obtained and the case where information is written with a current value based on a small mark waveform serving as a reference position will be described. FIG. 11 shows first to third waveforms W11 to W13 corresponding to the changing write current stored in the memory 62. In addition to these three waveforms, a mark waveform 111 of a high coercive force current value and a mark waveform 112 of a low coercive current value are stored in the memory 62.
[0155]
These mark waveforms 111 and 112 maintain the write current of the magnetic head 55 at the magnitude of the mark waveform for a short transport time for creating a small mark waveform (appearing as a bar graph in the figure).
[0156]
Therefore, before writing each of the waveforms W11 to W13, information is written with a current based on the mark waveforms 111 and 112 different from the waveforms W11 to W13. By providing these mark waveforms 111 and 112, all three waveforms W11 to W13 can be distinguished. In addition, since the mark waveforms 111 and 112 are set as reference positions for positioning the waveforms, the transport position of the magnetic card C can be easily obtained.
[0157]
When performing the preliminary writing in which the mark waveforms 111 and 112 are written, the same processing as the processing operation of the magnetic card C described in the flowchart of FIG. 7 is performed. Also, in step n14 of FIG. 7, when the magnetic head 55 reads the magnetic information written on the magnetic card C, the position of each of the waveforms W11 to W13 can be specified by reading each of the mark waveforms 111 and 112.
[0158]
Next, a write processing operation for writing the waveforms W11 to W13 and the mark waveforms 111 and 112 will be described with reference to the flowchart of FIG.
[0159]
The CPU 61 first drives the motor M to perform preliminary writing on the magnetic card C. As a result, the magnetic card is transported at a constant speed (step n41).
[0160]
At this time, when the magnetic card C conveyed along the card conveying path 54 comes into contact with the magnetic head 55, the CPU 61 sends the magnetic card C via the magnetic write control unit 63 prior to writing based on each of the waveforms W11 to W13. The write current of the head 55 is temporarily stopped (Step n42).
[0161]
Thereafter, when the magnetic card C reaches the position where the mark waveform is written, first, writing based on the mark waveform 111 with the high coercive force current value is started. If writing is performed for the transport distance based on the mark waveform 111, the writing of the mark waveform 111 with the high coercive force current value is completed (step n43).
[0162]
Subsequently, the writing current is stopped for a transport distance that can be distinguished from the mark waveform 112 based on the low coercive force current value (step n44).
[0163]
Thereafter, when the magnetic card C reaches the writing position of the mark waveform 112 with the low coercive force current value, the writing of the mark waveform 112 with the low coercive force current value is started (step n45).
[0164]
When writing is performed for the transport distance based on the mark waveform 112, the writing of the mark waveform 112 with the low coercive force current value is completed. In this way, information is written with the current value based on each of the mark waveforms 111 and 112 (step n46).
[0165]
Thereafter, the write current is stopped, and when a predetermined time elapses, the minimum current value is set, and the information is written by the current value based on the first waveform W11 which is written while gradually increasing the current value. Move on (step n47).
[0166]
One bit of information is written with the set minimum current value (step n48).
[0167]
It is determined whether a predetermined number of bits have been written (step n49). When it is determined that the data has not been written for the predetermined bit, the data is written again for one bit again (step n48). If it is determined that a predetermined number of bits have been written, the next current value is set in order to write the current value stepwise (step n50). Then, it is determined whether the writing of the first waveform has been completed (step n51). If the writing of the first waveform is not completed, one bit is written again (step n48).
[0168]
Until the first first waveform W11 (see FIG. 11) is obtained, the preliminary write operation of increasing the current value for each bit in accordance with the waveform is repeatedly performed stepwise (step n51).
[0169]
Thereafter, when it is determined that the writing based on the first first waveform W11 has been completed (step n51), the process proceeds to writing based on the next waveform. Also in this case, first, writing is performed based on the mark waveforms 111 and 112 in steps n42 to n46 described above. Thereafter, the procedure shifts again to the procedure (step n47 to step n52) for creating the next second waveform W12 (see FIG. 11), and information is written based on the second waveform W12. After writing the information based on the second waveform W12, the same procedure is repeated to write information based on the third waveform W13 (see FIG. 11) (steps n42 to n52).
[0170]
When the writing is completed, the writing current is stopped, the rotation of the motor M is stopped, the conveyance of the magnetic card C is stopped, and the preliminary writing is completed (step n53).
[0171]
In this way, information is written by applying a current value based on all the waveforms 111 and 112 and W11 to W13 to the magnetic head 55. Information is written based on all three waveforms W11 to W13 while the magnetic card C is conveyed in one direction from the starting end near the insertion slot of the card conveying path 54 to the rear end side.
[0172]
Next, an operation of detecting an appropriate write current value from a result of the preliminary write will be described with reference to a flowchart of FIG.
[0173]
The magnetic card C for which the preliminary writing has been completed is conveyed in a return direction to determine the suitability of the prewritten data. During this transport, the magnetic head 55 comes into contact with the magnetic card C, and the generated voltage is read based on the magnetic information written on the magnetic card C. From the voltage value at the time of reading, the reference position of the magnetic card C is detected from the mark waveforms 111 and 112 written on the magnetic card C (step n61).
[0174]
The CPU 61 searches for the maximum output voltage value from the read voltage values (step n62).
[0175]
Then, the distance from the detected reference position to the position where the searched maximum output voltage is obtained is obtained (step n63).
[0176]
At the card position corresponding to the obtained magnetic information, the current value of the information written at the time of preliminary writing is obtained. This becomes an appropriate current value for actual writing to the magnetic card C (step n64).
[0177]
In this case, since the mark waveforms 111 and 112 serve as references when positioning the waveforms W11 to W13, the recording position of the magnetic information on the magnetic card C can be accurately obtained.
[0178]
FIG. 14 shows an example of a write current value of a high coercive force magnetic card and a read result thereof. In the figure, one of the three waveforms is shown enlarged.
[0179]
Among these, the waveform data shown on the upper side in the drawing represents a waveform 141 that changes in accordance with the carry distance of the current value applied when the CPU 61 writes with the magnetic head 55 according to the program in the memory 62, and the write current (mA) ) And the transport distance (mm) are shown by waveform diagrams. The lower waveform data represents a waveform 142 that changes in accordance with the transport distance of the voltage value obtained when the voltage is read by the magnetic head 55, and shows the relationship between the output voltage (mV) and the transport distance (mm). It is represented by
[0180]
An appropriate write current value of the high coercive force magnetic card is obtained from the waveforms 141 and 142 that change in accordance with the transport distance. First, the write current value is changed with time from the lowest current value to the highest current value, and a waveform 141 that changes in accordance with the transport distance of the current value applied at the time of preliminary writing is stored in the memory 62. Let it be.
[0181]
After that, the maximum voltage value of the waveform 142 that changes in accordance with the voltage transport distance when the voltage is read by the magnetic head 55 is detected. Next, a waveform peak position 143 corresponding to the detected maximum voltage value is obtained. The write current value 144 that intersects the waveform peak position 143 and the card write position of the waveform 141 that changes in accordance with the upper transport distance stored in the memory 62 is a proper write current suitable for the high coercive force magnetic card. Value.
[0182]
FIG. 15 shows an example of a write current value of a low coercive force magnetic card and a read result thereof. In the figure, one of the three waveforms is shown enlarged.
[0183]
Similarly, in this case, the waveform data shown in the upper part of the drawing represents a waveform 151 that changes in accordance with the transport distance of the current value applied when the CPU 61 writes with the magnetic head 55 according to the program in the memory 62. (MA) and the transport distance (mm) are shown in a waveform diagram. The lower waveform data represents a waveform 152 that changes in accordance with the transport distance of a voltage value obtained when the voltage is read by the magnetic head 55, and illustrates a relationship between the output voltage (mV) and the transport distance (mm). It is represented by
[0184]
The appropriate write current value of the high coercive force magnetic card is obtained from the waveforms 151 and 152 that change in accordance with the transport distance. First, from the lowest current value to the highest current value, the write current value is changed over time and a waveform 151 that changes in accordance with the transport distance of the current value to be applied at the time of preliminary writing is stored in the memory 62. Keep it.
[0185]
After that, the maximum voltage value of the waveform 152 that changes in accordance with the voltage transport distance when the voltage is read by the magnetic head 55 is detected. Next, a waveform peak position 153 corresponding to the detected maximum voltage value is obtained. The write current value 154 that intersects the waveform peak position 153 and the card write position of the waveform 151 that changes in accordance with the upper transport distance stored in the memory 62 is a proper write current suitable for the low coercive force magnetic card. Value.
[0186]
Therefore, a write current value suitable for the coercive force of the magnetic card can be obtained regardless of whether the magnetic card has a high coercive force or a low coercive force magnetic card. Therefore, writing suitable for the coercive force of each magnetic card can be performed. In particular, in the case of a high coercive force magnetic card, the coercive force of the card often differs. Even for such high coercive force magnetic cards having different coercive forces, an appropriate write current value corresponding to each magnetic card can be obtained.
[0187]
Further, as shown in FIG. 16 and FIG. 17, the waveforms 161 and 171 which change in accordance with the voltage carrying distance shown on the lower side in the figure are unclear because the writing start positions 162 and 172 rise slowly. Hard to catch. On the other hand, the write end positions 163 and 173 of the waveforms 161 and 171 have high voltage values and are clear and easy to catch.
[0188]
For this reason, at both ends of the read regions 164 and 174 of the waveform from the write start positions 162 and 172 to the write end positions 163 and 173 for each waveform read by the magnetic head 55, the read write current value is large and clearly displayed. The write end positions 163 and 173 to be performed are set as waveform reference positions. Based on this reference position, the CPU 61 can determine the carry amount of the magnetic card C when reading by the magnetic head 55.
[0189]
In this way, even when the waveform to be written has an unclear writing start position or no mark waveform, the waveforms 161 and 171 themselves can have a writing reference position.
[0190]
FIG. 18 shows an example of a waveform that changes according to the transport distance in another embodiment in which the waveform itself has a reference position. One form of a waveform that changes in accordance with the transport distance is an intermittent waveform 181. The intermittent waveform 181 causes the output of the write current to be alternately repeated between output and stop at short time intervals when the magnetic head 55 writes while increasing the current value stepwise.
[0191]
By writing in this way, current is applied to the magnetic head 55 at short time intervals based on the intermittent waveform 181, and information is written. After the rising intermittent waveform 181, a current is applied to the magnetic head 55 based on the intermittent waveform 181 based on the short-time intermittent writing stop unit 182, and information is written. Therefore, the intermittent write stop unit 182 becomes the reference position of the waveform itself. In particular, since current is alternately applied based on the intermittent waveform 181 and the intermittent write stop unit 182 at short transport time intervals, even if a part of the intermittent waveform 181 disappears, it can be recognized.
[0192]
FIG. 19 shows an example of a waveform that changes according to the transport distance in another embodiment in which the waveform itself has a reference position. One form of the waveform that changes in accordance with the transport distance is an unaligned step-like waveform 191. This non-aligned step-like waveform 191 gradually increases the current value maintaining time T1 to T6... Every time the write current output is increased stepwise when writing with the magnetic head 55 stepwise increasing the current value. It is written differently to make it longer.
[0193]
If the writing is performed in this manner, since the sustain time for each write current value that is increased stepwise is different, the write waveform itself written stepwise is different due to the different time difference between the sustain times. Each of the different irregular staircase waveforms 191 is a reference position. Even with such output, the waveform itself can have a reference position.
[0194]
The waveforms shown in FIGS. 14 to 17 are represented by step-like waveforms like the waveforms shown in FIG. 8 and FIG. Is represented in
[0195]
The present invention is not limited to only the configuration of the above-described embodiment, and many embodiments can be obtained.
For example, in the above-described embodiment, the magnetic processing is performed while moving the magnetic card C to the positions of the stationary heads 35, 36, and 55. However, the present invention is not limited to this. The magnetic processing may be performed by moving the write head / read head or one magnetic head that combines writing and reading.
[Brief description of the drawings]
FIG. 1 is a control circuit block diagram of a card reader according to a first embodiment.
FIG. 2 is a flowchart illustrating a processing operation of the card reader according to the first embodiment;
FIG. 3 is an explanatory diagram illustrating a magnetic processing operation of the card reader according to the first embodiment.
FIG. 4 is a table showing examples of waveform data of various magnetic cards according to the first embodiment.
FIG. 5 is a schematic sectional view showing a card reader according to a second embodiment.
FIG. 6 is a control block diagram of the card reader according to the second embodiment.
FIG. 7 is a flowchart illustrating a card processing operation according to the second embodiment.
FIG. 8 is a waveform chart showing three waveforms at the time of preliminary writing according to the second embodiment.
FIG. 9 is a flowchart illustrating a waveform writing operation according to the second embodiment.
FIG. 10 is a flowchart for obtaining an appropriate write current value according to the second embodiment.
FIG. 11 is a waveform chart showing a waveform with a mark waveform according to the second embodiment.
FIG. 12 is a flowchart illustrating a write operation of a waveform with a mark waveform according to the second embodiment;
FIG. 13 is a flowchart for obtaining an appropriate write current value from a mark waveform according to the second embodiment;
FIG. 14 is a waveform chart showing an appropriate write current value of the high coercive force magnetic card according to the second embodiment.
FIG. 15 is a waveform chart showing an appropriate write current value of the low coercive force magnetic card according to the second embodiment.
FIG. 16 is a waveform chart showing reference positions of waveforms of the high coercive force magnetic card of the second embodiment.
FIG. 17 is a waveform chart showing reference positions of waveforms of the low coercive force magnetic card of the second embodiment.
FIG. 18 is a waveform chart showing an intermittent waveform and an intermittent write stop unit according to the second embodiment;
FIG. 19 is a waveform chart showing an irregular step-shaped waveform according to the second embodiment.
[Explanation of symbols]
30, 51… Card reader
32, 61 ... CPU
35 Write head
36 ... Reading head
40 ... ROM
55 ... Magnetic head
C: Magnetic card
62 ... Memory
81, 182: Write stop unit
111, 112 ... landmark waveform
W1 to W3, W11 to W13, 141, 142, 151, 152, 161, 171, 181, 191 ... waveform
143, 153 ... waveform peak position
144, 154: proper write current value

Claims (13)

While the magnetic recording medium is relatively moved in one direction with respect to the write head and the read head, the write head pre-writes the magnetic recording medium with a plurality of different current values, and writes the pre-written information to the read head. A magnetic recording method in which an appropriate value of a write current to the magnetic recording medium is obtained based on the read result, and a main write is performed on the magnetic recording medium by the write head with the obtained appropriate value. A write head for writing magnetic information to a magnetic recording medium;
A read head for reading magnetic information from the magnetic recording medium;
A magnetic recording device comprising control means for controlling these,
In the control means,
While the magnetic recording medium relatively moves in one direction with respect to the write head and the read head, a preliminary write process in which the write head performs preliminary write on the magnetic recording medium with a plurality of different current values;
A preliminary write / read process for reading a preliminary write result, which is a result of the preliminary write, with the read head;
Proper value acquisition processing for acquiring a proper value of a write current to the magnetic recording medium based on the preliminary write result;
A main writing process of performing main writing on the magnetic recording medium with the write head based on the appropriate value;
Magnetic recording device provided with. Conveying means for conveying the magnetic recording medium;
Transport amount detecting means for detecting the transport amount of the magnetic recording medium,
A write head that writes magnetic information on the magnetic recording medium with a plurality of different current values while the magnetic recording medium being conveyed by the conveying unit in one direction;
A write head for writing magnetic information on the magnetic recording medium by the write head, and then reading magnetic information on the magnetic recording medium being conveyed by the conveying means;
Determining means for determining a coercive force of the magnetic recording medium based on a voltage read by the read head and a transport amount of the magnetic recording medium at the time of reading;
An apparatus for determining a coercive force of a magnetic recording medium comprising: Conveying means for conveying the magnetic recording medium;
Transport amount detecting means for detecting the transport amount of the magnetic recording medium,
A write head for writing magnetic information to the magnetic recording medium being conveyed by the conveying means,
Write current waveform storage means for storing a waveform that changes in accordance with the carry amount of the write current value of the write head;
Write current changing means for changing a write current of the write head according to a write current value stored in the write current waveform storage means;
A write head for writing magnetic information on the magnetic recording medium by the write head, and then reading magnetic information on the magnetic recording medium being conveyed by the conveying means;
The coercive force of the magnetic recording medium is determined in accordance with the voltage read by the read head, the amount of conveyance of the magnetic recording medium at the time of reading, and the time change of the write current value stored in the write current waveform storage means. A coercive force determination device for a magnetic recording medium, comprising:
The coercive force determination device for a magnetic recording medium, wherein the write current changing means repeatedly changes the same waveform a plurality of times. 5. The apparatus according to claim 4, wherein during the repetition of the same waveform, the write head does not write the distance for separating the plurality of same waveforms. During the repetition of the same waveform, the write current changing means maintains the write current of the write head at the size of the waveform serving as the reference position for a time period for creating another waveform serving as the reference position. The apparatus for determining a coercive force of a magnetic recording medium according to claim 4. 5. The apparatus according to claim 4, wherein the write current changing means alternately repeats the write current of the write head between output and stop at predetermined intervals. 5. The magnetic recording medium according to claim 4, wherein the write current changing unit increases the write current of the write head in a stepwise manner, and changes the time for maintaining the current value each time the write current is increased. Coercive force determination device. Conveying means for conveying the magnetic recording medium;
Transport amount detecting means for detecting the transport amount of the magnetic recording medium,
A write head for writing magnetic information to the magnetic recording medium being conveyed by the conveying means,
Write current waveform storage means for storing a waveform that changes in accordance with the carry amount of the write current value of the write head;
Write current changing means for changing a write current of the write head according to a write current value stored in the write current waveform storage means;
A write head for writing magnetic information on the magnetic recording medium by the write head, and then reading magnetic information on the magnetic recording medium being carried on the magnetic recording medium;
The coercive force of the magnetic recording medium is determined in accordance with the voltage read by the read head, the amount of conveyance of the magnetic recording medium at the time of reading, and the time change of the write current value stored in the write current waveform storage means. A coercive force determination device for a magnetic recording medium, comprising:
At both ends of the waveform read area of the magnetic recording medium by the read head, the determination unit determines a transport amount of the magnetic recording medium when read by the read head based on a position where a read voltage value is large. An apparatus for determining a coercive force of a magnetic recording medium. A write head for writing magnetic information to a magnetic recording medium;
A read head for reading magnetic information of a magnetic recording medium;
Conveying means for conveying the write head and the read head;
Transport amount detecting means for detecting the transport amount of the write head and the read head,
Current changing means for changing a drive current of the write head during conveyance in one direction for conveying the write head by the conveyance means,
After the magnetic head writes the magnetic information to the magnetic recording medium by the write head, the read head is transported by the transport unit, and the read control unit reads the magnetic information of the magnetic recording medium;
Determining means for determining a coercive force of the magnetic recording medium based on a value read by the read head by the read control means, and a transport amount of the read head at the time of reading;
An apparatus for determining a coercive force of a magnetic recording medium comprising: Conveying means for moving the magnetic recording medium relative to the write head and the read head;
Transport amount detecting means for detecting an amount of movement by the transport means,
Write current changing means for changing a write current of the magnetic head while the transport means moves in one direction of the magnetic recording medium relatively moving with respect to the write head;
After the magnetic information is written on the magnetic recording medium by the write head, the magnetic information of the magnetic recording medium moving relative to the read head is read by the read head, and the voltage read by the read head is Determining means for determining a coercive force of the magnetic recording medium based on a movement amount at the time of reading;
An apparatus for determining a coercive force of a magnetic recording medium comprising: The apparatus for determining a coercive force of a magnetic recording medium according to claim 11,
The read head is provided with magnetic information storage means for reading magnetic information of the magnetic recording medium in advance and storing the magnetic information of the magnetic recording medium read in advance,
After the determination by the determination unit, the write head writes the magnetic information stored in the magnetic information storage unit to a magnetic recording medium with a current corresponding to the coercive force determined by the determination unit. An apparatus for determining a coercive force of a magnetic recording medium. Conveying means for moving the magnetic recording medium relative to the write head and the read head;
Transport amount detecting means for detecting an amount of movement by the transport means,
Write current changing means for changing a write current of the magnetic head during conveyance in one direction of the magnetic recording medium moving relative to the write head by the transfer means;
Write position detecting means for detecting a position where the write head has written on a magnetic recording medium;
After the magnetic information is written on the magnetic recording medium by the write head, the magnetic information of the magnetic recording medium moving relative to the read head is read by the read head, and the voltage read by the read head is Determining means for determining a coercive force of the magnetic recording medium based on a movement amount when reading and the written position;
An apparatus for determining a coercive force of a magnetic recording medium comprising:

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