JPH11283201A - Magnetic recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To speedily detect the coercive force of a magnetic medium and to perform recording on the magnetic medium with a recording current suitable for this coercive force. SOLUTION: A magnetic sensor part 5 is constituted by winding an exciting coil 3 and a detecting coil 4 around two main magnetic poles 2 juxtaposed so as to have a gap part 1 on one side at least, the magnetic sensor part 5 is provided so as to change magnetic flux passing through one main magnetic pole 2 with a magnetic medium 6 to be recorded with respect to the other main magnetic pole 2 and to detect a change in the magnetic flux at the main magnetic pole 2 with the detecting coil 4, a comparator part is provided for comparing this detecting output with a reference level, and the recording current to the magnetic medium 6 is determined corresponding to the output of this comparator part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a magnetic recording apparatus. More specifically, the present invention relates to a magnetic recording apparatus that identifies a coercive force of a magnetic medium and performs recording with a recording current suitable for the identification.

[0002]

2. Description of the Related Art In recent years, there has been a tendency to increase the coercive force of a magnetic medium such as a magnetic card in order to improve the recording density in magnetic recording, the S / N ratio of a signal, and the reliability of a signal with respect to an external magnetic field. It is in. However, it is difficult to increase the coercive force of all the used magnetic media at once, and magnetic media having different coercive forces will be used transiently or in the future in a mixed state. Therefore, the magnetic recording device is required to be compatible so that it can handle magnetic media having different coercive forces.

To cope with such diversification of the coercive force of the magnetic medium, a magnetic recording apparatus has a magnetic head according to the coercive force of the magnetic medium in order to obtain the maximum output and the S / N ratio when recording on the magnetic medium. It is required to adjust the recording current of the data. For this reason, it is necessary for the magnetic recording apparatus to first identify the coercive force of the magnetic medium before recording on the magnetic medium.

By the way, in a cassette tape or the like,
The case or the like is provided with a coercive force identification marking (the presence or absence of a hole in the case, the position of the hole, etc.). Therefore, in a magnetic recording device that handles a cassette tape or the like,
By identifying the coercive force of the cassette tape based on the marking when the medium is inserted, an appropriate recording current can be determined. However, a marking for recognizing a coercive force of a medium is not provided for a magnetic card or the like. For this reason, in the related art, first, a recording current value at which the output is maximized by repeatedly performing recording and reproduction several times with a recording current value corresponding to a coercive force that may be used first, and thereafter, the recording current value is determined. The data is updated with the value. In other words, when handling a magnetic medium such as a magnetic card which is not provided with a coercive force identification marking, the coercive force cannot be immediately identified from the magnetic layer of the magnetic medium, and recording / reproducing is repeated several times. This is performed to determine the coercive force of the magnetic medium.

[0005]

However, in the above-described magnetic recording apparatus which handles a magnetic card, the coercive force of the magnetic medium is determined by repeating the trial several times, so that the processing time becomes longer and the card transaction becomes longer. Takes a long time. Therefore, there has been a demand for the development of a device capable of detecting the coercive force of a magnetic medium without repeating several trials.

On the other hand, even when a magnetic medium having a marking for identifying the coercive force is used, the difference may be caused by a difference in the coercive force of the medium, a difference in thickness of the protective film layer provided on the medium, and the like. The optimum recording current value is slightly different.
Therefore, when the coercive force is identified based on the marking, it is not possible to adjust the difference in the value of the delicate optimum recording current, and even in this case, the coercive force of the magnetic medium is increased by another means. It would be convenient if it could be detected quickly.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic recording apparatus for quickly detecting the coercive force of a magnetic medium and performing recording on the magnetic medium with a recording current value suitable for this.

[0008]

In order to achieve the above object, a magnetic recording apparatus according to a first aspect of the present invention comprises an exciting coil and a detecting coil on two main magnetic poles juxtaposed so as to have a gap on at least one side. The magnetic sensor unit is formed by winding the magnetic sensor unit. The magnetic sensor unit is provided so that the magnetic flux passing through one of the main magnetic poles changes with respect to the other main magnetic pole depending on the magnetic medium on which the magnetic sensor unit is to be recorded. A change in the magnetic flux of the magnetic pole is detected by a detection coil, a comparison unit for comparing the detection output with a reference level is provided, and the recording current to the magnetic medium is determined by the output of the comparison unit.

Therefore, when no magnetic medium is inserted, the magnetic flux passing through the two main magnetic poles is balanced and no output is generated in the detection coil. In this state, when the magnetic medium is inserted, the magnetic flux leaks from the main magnetic pole to the magnetic medium. Therefore, the balance of the magnetic flux passing through the two main magnetic poles is lost, and an output is generated in the detection coil. Since the magnitude of the magnetic flux leaking from one main pole side to the magnetic medium side changes in accordance with the magnetic permeability of the magnetic medium, the degree of imbalance of the magnetic flux passing through the two main poles also changes, and the permeability and the magnetic permeability are maintained. Since the magnetic force has a certain relationship, the output of the detection coil corresponding to the coercive force of the magnetic medium can be obtained. This output is compared with a reference level stored in advance to determine a coercive force, and a recording current value suitable for the coercive force is determined.

[0010] The magnetic recording apparatus according to the second aspect of the present invention may be configured as follows.
Auxiliary cores are formed at the ends of the two main magnetic poles to assist the formation of a magnetic path by the magnetic medium. A detection coil is wound around each of the two main magnetic poles, and a differential output is extracted from the detection coils. The differential output is configured to be compared with a reference level.

Therefore, the magnetic flux leaking from one main pole to the magnetic medium is guided to the magnetic medium by the auxiliary core. The imbalance of the magnetic flux passing through the two main magnetic poles caused by the leakage of the magnetic flux is taken out as the differential output of the two detection coils. This operation output is compared with a reference level stored in advance to determine a coercive force, and a recording current value suitable for the coercive force is determined.

According to a third aspect of the present invention, in the magnetic recording apparatus, the main pole and the auxiliary core are made of a high-permeability magnetic material, and the two main poles are connected on the other side by a connecting portion. Is formed so as to protrude in a direction opposite to the connecting portion, and a portion between the protruding auxiliary core portions is a winding portion of the excitation coil or the detection coil.

The two main magnetic poles, the connecting portion and the respective auxiliary core portions have a substantially π shape as a whole. When the magnetic flux passing through each main magnetic pole forms one closed loop as a whole, the magnetic flux is applied to one main magnetic pole → the air gap → the other main magnetic pole →
A loop is formed in the order of the connecting part → one main pole or in the reverse order. Since the main pole and the auxiliary core are made of a high-permeability magnetic material, the leakage of magnetic flux from the closed loop hardly occurs. By making the portion between each auxiliary core portion of each main pole the winding portion of the excitation coil or the detection coil, it becomes possible to symmetrically wind each coil with respect to both main poles, The passing magnetic flux can be balanced.

In this case, the magnetic medium is a magnetic stripe provided on a magnetic card, and the position at which the magnetic stripe acts on one of the two main magnetic poles is determined. The main pole may be provided substantially parallel or substantially perpendicular to the card running plane of the card insertion slot so that the card can pass through.

Further, in the magnetic recording apparatus according to the fifth aspect,
A magnetic sensor unit is constituted by an excitation core portion wound with an excitation coil and two detection core portions which are arranged side by side so as to sandwich the excitation core portion and have a gap on one side and each of which is wound with a detection coil. The magnetic sensor is provided so that the magnetic flux passing through one of the two detection cores changes depending on the magnetic medium on which the magnetic recording is to be performed, and the change in the magnetic flux is detected by the detection coil. A comparison unit for comparing with a level is provided, and a recording current to the magnetic medium is determined based on an output of the comparison unit.

Therefore, in a state where the magnetic medium is not inserted, the magnetic flux passing through the two detection cores is balanced, and no differential output is generated between the respective detection coils. In this state, when the magnetic medium is inserted, the magnetic flux leaks from the one detection core to the magnetic medium. For this reason, the balance of the magnetic flux passing through each detection core unit is lost, and a differential output is generated between the detection coils. Since the magnitude of the magnetic flux leaking from one of the detection core portions changes according to the magnetic permeability of the magnetic medium, the degree of imbalance of the magnetic flux passing through each detection core portion also changes,
Because there is a certain relationship between permeability and coercivity,
A differential output between the detection coils according to the coercive force of the magnetic medium is obtained. The coercive force is determined by comparing the differential output with a reference level, and a recording current value suitable for the coercive force is determined.

In this case, two grooves are formed from one side surface of the integral core body, and the excitation core portion is formed at the center and the detection core portions are formed on both sides of the integrated core body. The differential output may be taken out by two detection coils formed and wound around two detection cores, and the differential output may be compared with a reference level.

According to a seventh aspect of the present invention, there is provided a magnetic recording apparatus, wherein the detection coil is wound and the detection core is sandwiched between the detection core and a gap is formed on one side. A magnetic sensor section comprising the two exciting core sections described above, and a magnetic medium passing through one of the two exciting core sections depending on a magnetic medium on which the magnetic sensor section is to be recorded is provided so as to be changed. Is detected by a detection coil, and a comparison unit for comparing the detection output with a reference level is provided, and the output of the comparison unit determines the recording current to the magnetic medium.

Therefore, when no magnetic medium is inserted, the magnetic flux passing through the two excitation cores is balanced, and no output is generated in the detection coil wound around the detection core.
From this state, when the magnetic medium is inserted, the magnetic flux leaks from the one excitation core to the magnetic medium. For this reason, the balance of the magnetic flux passing through each excitation core unit is lost, and an output is generated in the detection coil. Since the magnitude of the magnetic flux leaking from one of the excitation cores changes according to the magnetic permeability of the magnetic medium, the degree of imbalance of the magnetic flux passing through each of the excitation cores also changes, and between the magnetic permeability and the coercive force. Since there is a certain relationship between the two, an output value of the detection coil corresponding to the coercive force of the magnetic medium can be obtained. This output is compared with a reference level to determine a coercive force, and a recording current value suitable for the coercive force is determined.

In this case, two grooves are formed from one side surface of the integral core body, and a detection core portion is formed at the center, and excitation core portions are formed on both sides of the core portion. An output may be taken out by a detection coil formed and wound around a detection core unit, and the output may be compared with a reference level.

Further, as in the magnetic recording apparatus according to the ninth aspect, the magnetic medium is a magnetic stripe provided on a magnetic card, and the magnetic sensor section is at or near the magnetic stripe of the magnetic card inserted from the card insertion slot. However, the data track formed on the magnetic stripe may be provided at an off-position.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail based on the best mode shown in the drawings.

FIGS. 1 to 5 show a first embodiment of a magnetic recording apparatus to which the present invention is applied. In this magnetic recording device, an exciting coil 3 and a detecting coil 4 are wound around two main magnetic poles 2 juxtaposed so as to have a gap 1 on at least one side, and a magnetic sensor unit 5 is formed. Is provided so that the magnetic flux passing through one of the main magnetic poles 2 changes depending on the magnetic medium 6 to be recorded, and the change in the magnetic flux of one of the main magnetic poles 2 is detected by the detection coil 4. A comparison unit 21 for comparing with a reference level is provided, and a recording current to the magnetic medium 6 is determined based on an output of the comparison unit 21. In the magnetic sensor unit 5 of the present embodiment, the gap 1 is provided only on one side of each main pole 2, and the other side of each main pole 2 is connected by the connecting unit 8.

At the ends of the two main magnetic poles 2 of the magnetic sensor section 5, an auxiliary core section 7 for assisting the magnetic medium 6 in forming a magnetic path is formed. Each auxiliary core portion 7 is formed so as to protrude to the opposite side from the connecting portion 8. Each of the main magnetic poles 2 and each of the auxiliary cores 7 are integrally formed of a magnetic material having a high magnetic permeability such as ferrite, and a winding unit that winds the exciting coil 3 and the detection coil 4 between the auxiliary cores 7. Nine.

The exciting coil 3 is wound around the winding 9 of each main magnetic pole 2. The exciting coils 3 are wound in opposite directions, and the magnetic fluxes passing through the main magnetic poles 2 are opposite to each other, so that a closed-loop magnetic flux Φ1 is generated as a whole.

The leads 3a, 3a,
The reference numerals 4a are arranged so as to have the same positional relationship with respect to each main pole 2 so that the magnetic flux passing through each main pole 2 is balanced. That is, the main magnetic poles 2 are equidistant with respect to the virtual intermediate axis L so as to have a plane-symmetric positional relationship based on a virtual intermediate plane existing equidistant from each main magnetic pole 2 or as shown in FIG. When viewed from the direction of FIG. 3A (the direction of the arrow A in FIG. 3B), the coils 3 and 3 have a point-symmetrical positional relationship based on the virtual intermediate axis L.
Four lead lines 3a and 4a are arranged. By arranging the leads 3a and 4a of the coils 3 and 4 in this manner, the magnetic flux passing through the main magnetic poles 2 can be balanced. However, not necessarily in such a positional relationship,
It is not necessary to arrange the four lead wires 3a, 4a, and the magnetic flux passing through each main magnetic pole 2 may be balanced by a circuit electrically connected to each coil 3, 4. Also, the exciting coil 3 is supplied with an exciting current sufficient to detect the magnetic permeability of the magnetic medium 6 in a region where the high magnetic permeability core members of the main magnetic poles 2 and the auxiliary core portions 7 are not magnetically saturated. ing.

This magnetic recording apparatus is, for example, a magnetic card 1
4 with respect to the card running plane A of the card insertion slot 30 so that the magnetic stripe 15 as the magnetic medium 6 passes through a position acting on one of the two main magnetic poles 2. The main magnetic poles 2 are arranged so as to be substantially parallel.

The magnetic sensor unit 5 of this magnetic recording device includes:
For example, the circuit shown in FIG. 2 is connected. Excitation coil 3
Are connected to, for example, an AC power supply 10 and generate a closed-loop magnetic flux Φ1 through the two main magnetic poles 2. Magnetic medium 6 (magnetic stripe 15) around magnetic sensor unit 5
Does not exist and the magnetic flux passing through each main pole 2 is equal, the magnetic flux passing through each main pole 2 is balanced, and the output of the detection coil 4 does not change. When the magnetic medium 6 approaches the magnetic sensor unit 5 from this state, the auxiliary core unit 7
Magnetic flux Φ2 leaking toward the magnetic medium 6 through the
The balance of the magnetic flux passing through each main pole 2 is lost. Since the degree of leakage of the magnetic flux Φ2 changes depending on the magnetic permeability of the magnetic medium 6,
The output of the detection coil 4 changes according to the magnitude of the magnetic permeability. After the output of the detection coil 4 is amplified by the amplifier circuit 11, it is half-wave rectified by the detection circuit 12 and the peak hold circuit 13 and subjected to envelope detection, and becomes an output signal having a magnitude corresponding to the magnetic permeability of the magnetic medium 6. . In this case, the order of amplification and detection may be reversed. Since there is a certain relationship between the magnetic permeability of the magnetic medium 6 and the magnitude of the coercive force of the magnetic medium 6, the output of the detection coil 4 corresponding to the magnitude of the coercive force is stored in advance as a reference level, By performing comparison with the reference level, the coercive force of the magnetic medium 6 can be identified based on the output of the detection coil 4.

That is, in this magnetic recording apparatus, each excitation coil 3 is wound around a substantially π-shaped high magnetic permeability core member so that the magnetic flux Φ1 forms a closed loop, and the detection coil 4 becomes a differential type. It is wound. Therefore, when the magnetic medium 6 approaches the magnetic sensor unit 5, most of the magnetic flux Φ1 forms a closed loop, but the minimum magnetic flux Φ2 depending on the medium permeability of the magnetic medium 6 acts on the magnetic medium 6. Therefore, a magnetic flux large enough to impair the recording data does not act on the magnetic medium 6, and the magnetic sensor unit 5 can be operated even on the data storage area of the magnetic medium 6. That is, the magnetic medium 6
Is the magnetic stripe 1 of the magnetic card 14 shown in FIG.
In the case of 5, the magnetic sensor unit 5 may be opposed to a free area (guard band) 17 between the tracks 16 which are storage areas in the magnetic stripe 15, but may be opposed to the track 16. . Therefore, the degree of freedom in installing the magnetic sensor unit 5 is improved.

The magnetic sensor unit 5 of this magnetic recording apparatus is mounted at a position 19 of the card insertion slot 30 which can face the magnetic stripe 15 as shown in FIG. 4, for example.
By attaching the magnetic sensor unit 5 to the card insertion slot 30, the magnetic stripe 1 is inserted when the magnetic card 14 is inserted.
5 can be detected, and subsequent processing such as data recording can be quickly performed. The magnetic sensor unit 5 may be provided at the tip of the card insertion slot 30 as illustrated,
Alternatively, it may be provided at a position between the shutter and an internal shutter.

When the magnetic card 14 is inserted into the card insertion slot 30, an output depending on the effective magnetic permeability of the magnetic circuit composed of the magnetic stripe (magnetic layer) 15 and the magnetic sensor unit 5 is output. 5 That is, the output level from the magnetic sensor unit 5 varies depending on the magnitude of the magnetic permeability of the magnetic stripe 15 of the magnetic card 14, and since there is a certain relationship between the magnetic permeability and the coercive force, The coercive force of the magnetic stripe 15 can be detected based on this level difference.

As shown in FIG. 5, this magnetic recording apparatus
The above-described magnetic sensor unit 5, level detection unit 20, comparison unit 2
1, a reference level memory 22, a controller 23, and a magnetic head 24. An output signal from the magnetic sensor unit 5 is supplied to a level detection unit 20, and information on the level of the output signal is supplied to a comparison unit 21. The comparing section 21 compares this information with the reference level stored in the reference level memory 22. The reference level memory 22 stores the output signal level of the magnetic sensor unit 5 corresponding to the magnitude of the coercive force of the magnetic card 14 that may be used. The comparing unit 21 identifies the coercive force of the magnetic stripe 15 by comparing each level stored in the memory 22 with the level of the output signal. The recording current determination unit 23a of the controller 23 determines an optimum recording current value for the identified coercive force of the magnetic stripe 15, and the controller 23 operates the magnetic head 24 at the determined recording current value. That is, the recording current value of the magnetic head 24 when recording on the magnetic stripe 15 is determined by the output of the comparison unit 21. Thereby, recording is performed with a recording current value suitable for the coercive force of the magnetic card 14.

The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without departing from the gist of the present invention. For example, in the above description, the main magnetic poles 2 are arranged so as to be substantially parallel to the card running plane A of the card insertion slot 30, but in the second embodiment of the magnetic recording apparatus shown in FIG. Thus, the card running plane A of the card insertion slot 30
However, the main magnetic poles 2 may be arranged almost vertically. In this case, when the positional relationship between the magnetic medium 6 and each main magnetic pole 2 becomes equal, the magnetic flux passing through each main magnetic pole 2 is balanced and the output of the detection coil 4 cannot be obtained. The magnetic sensor unit 5 is provided at a position that affects only the magnetic flux of one main pole 2, that is, the magnetic sensor unit 5 is arranged so that only one main pole 2 is opposed to the path along which the magnetic medium 6 relatively moves. So that when the magnetic medium 6 approaches one of the main magnetic poles 2, the balance of the magnetic flux passing through each main magnetic pole 2 is lost. Alternatively, even when the magnetic sensor unit 5 is installed so that both the main magnetic poles 2 face the path in which the magnetic medium 6 relatively moves, the relatively moving magnetic medium 6 passes through one main magnetic pole 2. The magnetic permeability of the magnetic medium 6 is detected at a stage where only the magnetic flux is affected, that is, in a state where the magnetic fluxes of the two main magnetic poles 2 are not balanced. In this case, the magnetic medium 6 faces both main magnetic poles 2 after the detection of the magnetic permeability. At this time, most of the magnetic flux flowing through each main magnetic pole 2 passes through the magnetic medium 6. Therefore, whether to detect the magnetic permeability using a magnetic flux of a strength that does not impair the recorded data,
Alternatively, for example, the magnetic sensor unit 5 may be made to face the empty area 17 of the magnetic stripe 15 of the magnetic card 14.

In the above description, the auxiliary cores 7 are formed at both ends of each main pole 2. However, the auxiliary cores 7 need not always be formed at both ends, and one side of each main pole 2 is not necessary. The auxiliary core part 7 may be formed only in the auxiliary core part 7, or the auxiliary core part 7 may be omitted. For example, as in the third embodiment of the magnetic recording apparatus shown in FIG. 7 and the fourth embodiment of the magnetic recording apparatus shown in FIG. 8, the auxiliary core unit 7 may be omitted.

In the above description, the exciting coils 3 of the respective main magnetic poles 2 are wound in opposite directions so that the direction of the magnetic flux passing through the respective main magnetic poles 2 is reversed to generate a magnetic flux Φ1 which forms a closed loop. However, as in the fifth embodiment of the magnetic recording apparatus shown in FIG. 9, the exciting coil 3 of each main magnetic pole 2 is wound in the same direction so that the magnetic flux passing through each main magnetic pole 2 becomes a magnetic flux Φ3 going in one direction. You may make it become. In this case, when the magnetic medium 6 approaches, most of the magnetic flux passing through the one main magnetic pole 2 becomes the magnetic flux Φ2 passing through the magnetic medium 6, so that the magnetic permeability is reduced by using a magnetic flux having a strength that does not impair the recording data. The detection may be performed or, for example, the magnetic sensor unit 5 may be opposed to the empty area 17 of the magnetic stripe 15 of the magnetic card 14.

In the above description, the excitation coil 3 is wound around each of the main magnetic poles 2. However, as in the sixth embodiment of the magnetic recording apparatus shown in FIG. 10, one excitation coil 3 is provided. It may be.

In the above description, one detection coil 4 is wound around two main magnetic poles 2. However, for example, as in the seventh embodiment of the magnetic recording apparatus shown in FIG. Alternatively, the detection coil 4 may be wound around each of the detection coils 2 to extract a differential output from each detection coil 4.

Further, as in the eighth embodiment of the magnetic recording apparatus shown in FIG. 12, the detection coil 4 may be wound so as to include two main magnetic poles 2.

As in the ninth embodiment of the magnetic recording apparatus shown in FIG. 13, an exciting core 31 around which an exciting coil 3 is wound and a gap 1 sandwiching the exciting core 31 and having a gap 1 on one side. The magnetic sensor unit 5 may be configured by two detection core units 32 that are juxtaposed and each have the detection coil 4 wound therearound. Then, this magnetic sensor unit 5 is
The magnetic medium 6 is installed so that the magnetic flux passing through one of the detection core portions 32 changes, and the change in the magnetic flux is detected by the detection coil 4.
And a comparison unit 21 for comparing the detection output with a reference level may be provided, and the recording current to the magnetic medium 6 may be determined based on the output of the comparison unit 21. That is, two groove portions 3 are formed from one side surface of the integral core body 33.
4, the excitation core 31 is formed at the center, and the detection cores 32 are formed on both sides thereof. The differential output is taken out by the two detection coils 4 wound around the two detection cores 32. The differential output may be compared with a reference level.

In this case, when the magnetic medium 6 is not detected, the magnetic flux passing through the two detection cores 32 is balanced, and no differential output occurs between the respective detection coils 4.
In this state, when the magnetic medium 6 connects one of the detection core portions 32 and the excitation core portion 31 as shown in FIG.
Is generated. Therefore, the balance of the magnetic flux passing through the two detection cores 32 is lost, and each detection coil 4
A differential output occurs between them. Since the magnitude of the magnetic flux Φ2 leaking from one of the detection core portions 32 changes in accordance with the magnetic permeability of the magnetic medium 6, the degree of imbalance of the magnetic flux passing through each of the detection core portions 32 also changes. Since there is a certain relationship with the coercive force, a differential output value between the respective detection coils 4 according to the coercive force of the magnetic medium 6 can be obtained. In this embodiment, a magnetic flux Φ2 that causes each detection coil 4 to generate a differential output is generated between the detection core parts 32, and the magnetic flux Φ2 of each of the core parts 31, 32 around which the coils 3, 4 are wound. Since a certain amount of mass exists as the core body 33 in a portion opposite to the magnetic medium 6, when the magnetic sensor unit 5 is mounted at a predetermined position, the magnetic sensor unit 5 is not affected by other external magnetic fields, metal members, magnetic materials, and the like. And the magnetic sensor unit 5 can be made to react sensitively only to the magnetic medium 6.

The tenth embodiment of the magnetic recording apparatus shown in FIG.
As in the first embodiment, the detection core portion 32 around which the detection coil 4 is wound, and the excitation coil 3 around which the detection coil portion 32 is sandwiched and the excitation coil 3 is wound so as to have a gap 1 on one side. The magnetic sensor unit 5 by the two excitation core units 31
May be configured. The magnetic sensor unit 5 is installed such that the magnetic flux passing through one of the two exciting core portions 31 is changed by the magnetic medium 6, and the change in the magnetic flux due to the magnetic medium 6 is detected by the detection coil 4. And a comparison unit 21 for comparing the detection output with a reference level may be provided, and the output of the comparison unit 21 may be used to determine the recording current for the magnetic medium. That is, two groove portions 34 are formed from one side surface of the integral core body 33,
The detection core 32 may be formed at the center and the excitation cores 31 may be formed on both sides of the detection core 32. The output may be taken out by the detection coil 4 wound around the detection core 32, and the output may be compared with a reference level. .

In this case, when the magnetic medium 6 is not detected, the magnetic flux passing through the two excitation cores 31 is balanced, and no output is generated in the detection coil 4 wound around the detection core 32. From this state, when the magnetic medium 6 connects the one excitation core unit 31 and the detection core unit 32 as illustrated,
A magnetic flux Φ2 flowing from one of the excitation core portions 31 to the detection core portion 32 is generated. Therefore, the two excitation core portions 31
The balance of the magnetic flux passing through the detection coil 4 is lost, and an output is generated in the detection coil 4. One excitation core 3 according to the magnetic permeability of the magnetic medium 6
Since the magnitude of the magnetic flux Φ2 leaking from the first side changes, the degree of imbalance of the magnetic flux passing through each of the excitation core portions 31 also changes,
Further, since there is a certain relationship between the magnetic permeability and the coercive force, an output value of the detection coil 4 corresponding to the coercive force of the magnetic medium 6 can be obtained. In this embodiment, the magnetic flux Φ2 is generated between the excitation core portions 31 and the coils 3, 4
There is a certain amount of mass as the core body 33 in the portion of each of the core portions 31 and 32 on the side opposite to the magnetic medium 6 around which the magnetic sensor portion 5 is mounted. The magnetic sensor unit 5 becomes less susceptible to the influence of other external magnetic fields, metal members, magnetic materials, and the like, and can be made to react sensitively only to the magnetic medium 6.

In the above description, the magnetic sensor unit 5 is attached to the card insertion slot 30.
Is not limited to this position. For example, the magnetic sensor unit 5 may be mounted on the back side of the card insertion slot 30. Even in this case, as in the case described above,
The coercive force of the magnetic stripe 15 of the magnetic card 14 can be identified.

Further, in the above description, one main pole 2
The magnetic medium 6 acts only on the magnetic flux passing through the main magnetic pole 2, but the magnetic medium 6 may act only on the magnetic flux passing through the other main magnetic pole 2 instead of the one main magnetic pole 2. is there.

When the magnetic sensor unit 5 is manufactured, it is sufficient to insert an externally manufactured air-core coil into the main magnetic pole 2.
Its manufacture is easy.

[0046]

EXAMPLE An experiment was conducted to confirm that the level of the output signal of the magnetic sensor unit 5 changes according to the coercive force of the magnetic stripe 15 of the magnetic card 14. The magnetic sensor unit 5 shown in FIG. 1 was used. As magnetic cards, three types of cards having the same coercive force as those actually used for transactions, specifically, coercive forces of 300, 650 and 27 are used.
A 50 (Oe) magnetic card 14 was used. For reference, the output in a state where the magnetic stripe 15 of the magnetic card 14 was not detected was also confirmed. Magnetic stripe 15
FIG. 15 shows the output of the magnetic sensor unit 5 in a state where no
FIG. 16 shows the output of the magnetic sensor unit 5 when the magnetic stripe 15 having a coercive force of 300 (Oe) is detected, and the output of the magnetic sensor unit 5 when the magnetic stripe 15 having a coercive force of 650 (Oe) is detected. The output is shown in FIG.
FIG. 18 shows the output of the magnetic sensor unit 5 when the (Oe) magnetic stripe 15 is detected. Note that FIG.
17 to 50, one scale on the vertical axis is 50 mV, whereas in FIG. 18, one scale on the vertical axis is 20 mV. As is clear from these results, it was confirmed that the output level of the magnetic sensor unit 5 differs depending on the coercive force of the magnetic stripe 15 of the magnetic card 14. That is, by storing these levels in the memory 22 as reference levels, it was confirmed that the coercive force of the magnetic stripe 15 could be identified by comparison with the reference levels. Although the drive is performed using the excitation current of the sine wave, the drive may be performed using the excitation current of a rectangular wave, a triangular wave, or the like without being limited to the excitation current of the sine wave.

[0047]

As described above, in the magnetic recording apparatus according to the first aspect, the excitation coil and the detection coil are wound around the two main magnetic poles juxtaposed so as to have a gap on at least one side. The magnetic sensor unit is provided so that the magnetic flux passing through one of the main magnetic poles changes with respect to the other main magnetic pole depending on the magnetic medium on which the magnetic sensor unit is to be recorded. A detection unit is used for detection, and a comparison unit for comparing the detection output with a reference level is provided. The recording current to the magnetic medium is determined based on the output of the comparison unit, so that the coercive force of the magnetic medium can be quickly increased. Upon detection, recording on a magnetic medium can be performed with a recording current suitable for this coercive force. For example, when the present invention is applied to a magnetic recording device that handles a magnetic medium having no coercive force identification marking such as a magnetic card such as a credit card, when the magnetic medium is inserted into the magnetic recording device, the coercive force is identified at the same time. As a result, data can be recorded immediately with the optimum recording current value. For this reason, data recording or the like can be performed in one process, and the processing time can be significantly reduced. Further, even when the present invention is applied to a magnetic recording apparatus that handles a magnetic medium having an identification marking in a case or the like, a difference in media coercive force,
A subtle difference such as a difference in thickness of the protective film layer provided on the medium can be reflected on the recording current value, and the quality and reliability of data processing can be improved. further,
Since each main pole and the core member of the auxiliary core can be used in a region where magnetic saturation does not occur, coercive force can be detected without destroying data already recorded on the magnetic medium, and data can be used. Since the magnetic sensor unit may be installed so as to face the recorded area, the degree of freedom in installing the magnetic sensor unit is improved.

In this case, as in the magnetic recording device according to the second aspect, an auxiliary core portion for assisting the formation of a magnetic path by the magnetic medium is formed at the ends of the two main magnetic poles, and each of the two main magnetic poles has The detection coil may be wound, a differential output may be taken out from the detection coil, and the differential output may be compared with a reference level. Further, as in the magnetic recording device according to the third aspect, the main magnetic pole and the auxiliary core portion are made of a high magnetic permeability magnetic material, the other sides of the two main magnetic poles are connected by a connecting portion, and provided at both ends of the main magnetic pole. The provided auxiliary core portion may be formed so as to protrude in a direction opposite to the connecting portion, and a portion between the protruded auxiliary core portions may be used as a winding portion of the excitation coil or the detection coil. Further, as in the magnetic recording apparatus according to claim 4, the magnetic medium is a magnetic stripe provided on a magnetic card, and the magnetic medium passes through a position acting on one of the two main magnetic poles. The main magnetic pole may be provided substantially parallel or substantially perpendicular to the card running plane of the card insertion slot. In these cases, the same effects as those described above can be obtained.

Further, as in the magnetic recording apparatus according to the fifth aspect, the exciting coils are wound and the exciting coils are juxtaposed so as to sandwich the exciting core and have a gap on one side thereof. A magnetic sensor section is formed by the two wound detection core sections, and the magnetic sensor section is provided such that the magnetic flux passing through one of the two detection core sections varies depending on the magnetic medium on which the magnetic sensor section is to be recorded. Alternatively, a configuration may be adopted in which a change in magnetic flux is detected by a detection coil, a comparison unit for comparing the detection output with a reference level is provided, and a recording current to the magnetic medium is determined based on an output of the comparison unit. Further, as in the magnetic recording device according to the sixth aspect, two grooves are formed from one side surface of the integral core body, and the excitation core portion is formed at the center and the detection core portions are formed on both sides thereof. A differential output may be extracted by two detection coils wound around one detection core unit, and the differential output may be compared with a reference level. In these cases, a magnetic flux that generates a differential output in each detection coil is generated between the detection core portions, and a part of each core portion opposite to the magnetic medium is formed as a core body to some extent. Because there is a mass of the magnetic sensor, a stable magnetic sensor unit having directivity that is hardly affected by external magnetic fields, nearby metals, external magnetic materials, and the like can be configured, and the magnetic sensor unit can be freely installed. The degree can be further improved. Further, the same effect as the effect of the magnetic recording apparatus according to the first aspect can be obtained.

Further, as in the magnetic recording apparatus of the present invention, the exciting coils are arranged side by side so as to sandwich the detecting core portion around which the detecting coil is wound and to have a gap portion on one side while sandwiching the detecting core portion. A magnetic sensor section is constituted by the two wound excitation core sections, and the magnetic sensor section is provided so that a magnetic flux passing through one of the two excitation core sections varies depending on a magnetic medium on which the magnetic sensor section is to be recorded. Alternatively, a configuration may be adopted in which a change in magnetic flux is detected by a detection coil, a comparison unit for comparing the detection output with a reference level is provided, and a recording current to the magnetic medium is determined based on an output of the comparison unit. Further, as in the magnetic recording device according to the eighth aspect, two grooves are formed from one side surface of the integral core body, and a detection core portion is formed at the center, and excitation core portions are formed on both sides of the detection core portion. The output may be taken out by a detection coil wound around the core, and the output may be compared with a reference level. In these cases, a magnetic flux for generating an output in the detection coil is generated between the exciting core portions, and a certain amount of mass is formed as a core body in a portion of each core portion opposite to the magnetic medium. Since it is present, a stable magnetic sensor unit having directivity that is hardly affected by external magnetic fields, nearby metals, external magnetic materials, and the like can be configured, and the degree of freedom in installing the magnetic sensor unit can be increased. Can be improved. Further, the same effect as the effect of the magnetic recording device according to the first aspect can be obtained.

Further, in the magnetic recording apparatus according to the ninth aspect, the magnetic medium is a magnetic stripe provided on the magnetic card, and the magnetic sensor portion is at or near the magnetic stripe of the magnetic card inserted from the card insertion slot. Therefore, the data recorded on the data track can be prevented from being destroyed when the coercive force of the magnetic stripe is detected.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a magnetic recording apparatus according to the present invention, and is a schematic configuration diagram of a magnetic sensor unit thereof.

FIG. 2 is a circuit diagram connected to a magnetic sensor unit of the magnetic recording device of the present invention.

FIG. 3 is a plan view showing a magnetic stripe of the magnetic card.

FIG. 4 is a perspective view of the vicinity of a card insertion slot of the magnetic recording apparatus of the present invention.

FIG. 5 is a block diagram of a first embodiment of the magnetic recording device of the present invention.

FIG. 6 shows a second embodiment of the magnetic recording apparatus of the present invention, and is a schematic configuration diagram of a magnetic sensor unit thereof.

FIG. 7 shows a third embodiment of the magnetic recording apparatus according to the present invention, and is a schematic configuration diagram of a magnetic sensor unit thereof.

FIG. 8 shows a fourth embodiment of the magnetic recording apparatus of the present invention, and is a schematic configuration diagram of a magnetic sensor unit thereof.

FIG. 9 is a schematic configuration diagram of a magnetic sensor unit according to a fifth embodiment of the magnetic recording apparatus of the present invention.

FIG. 10 shows a sixth embodiment of the magnetic recording apparatus of the present invention, and is a schematic configuration diagram of a magnetic sensor unit thereof.

FIG. 11 shows a seventh embodiment of the magnetic recording apparatus of the present invention, and is a schematic configuration diagram of a magnetic sensor unit thereof.

FIG. 12 shows an eighth embodiment of the magnetic recording apparatus according to the present invention, and is a schematic configuration diagram of a magnetic sensor unit thereof.

FIG. 13 shows a ninth embodiment of the magnetic recording apparatus of the present invention, and is a schematic configuration diagram of a magnetic sensor unit thereof.

FIG. 14 shows a tenth embodiment of the magnetic recording apparatus of the present invention, and is a schematic configuration diagram of a magnetic sensor unit thereof.

FIG. 15 is a diagram showing an example of an output signal of a magnetic sensor unit of the magnetic recording apparatus according to the present invention, in a state where nothing is detected.

FIG. 16 is a diagram illustrating an example of an output signal of a magnetic sensor unit of the magnetic recording apparatus according to the present invention, in a case where a magnetic stripe having a coercive force of 300 (Oe) is detected.

FIG. 17 is a diagram illustrating an example of an output signal of a magnetic sensor unit of the magnetic recording apparatus of the present invention, in a case where a magnetic stripe having a coercive force of 650 (Oe) is detected.

FIG. 18 is a diagram illustrating an example of an output signal of a magnetic sensor unit of the magnetic recording apparatus according to the present invention, in a case where a magnetic stripe having a coercive force of 2750 (Oe) is detected.

19A and 19B show the arrangement of lead wires of an exciting coil and a detection coil, wherein FIG. 19A is a view of a main pole viewed from a direction along a virtual intermediate axis, and FIG. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air gap part 2 Main pole 3 Excitation coil 4 Detection coil 5 Magnetic sensor part 6 Magnetic medium 7 Auxiliary core part 8 Connecting part 9 Winding part 19 Magnetic detection position 31 Excitation core part 32 Detection core part 33 Core body 34 Groove part

Claims (9)

[Claims] An exciting coil and a detecting coil are wound around two main magnetic poles juxtaposed so as to have a gap on at least one side, and a magnetic sensor unit is formed, and a magnetic medium on which the magnetic sensor unit is to be recorded is provided. The magnetic flux passing through one main pole of the main magnetic poles is provided so as to be changed with respect to the other main magnetic pole, and the change in the magnetic flux of the one main magnetic pole is detected by the detection coil. A magnetic recording apparatus, comprising: a comparing section for comparing with a reference level; and determining a recording current to the magnetic medium based on an output of the comparing section. 2. An auxiliary core portion is formed at an end of the two main magnetic poles to assist in forming a magnetic path by the magnetic medium. A detection coil is wound around each of the two main magnetic poles. 2. The magnetic recording apparatus according to claim 1, wherein a differential output is taken out from a detection coil, and the differential output is compared with the reference level. 3. The main magnetic pole and the auxiliary core portion are made of a high-permeability magnetic material. The two main magnetic poles are connected on the other side by a connecting portion, and the auxiliary cores provided at both ends of the main magnetic pole are provided. 3. The magnetic recording apparatus according to claim 2, wherein the portion is formed so as to protrude in a direction opposite to the connecting portion, and a space between the protruding auxiliary core portions is a winding portion of the exciting coil or the detecting coil. apparatus. 4. The card running of the card insertion slot so that the magnetic medium is a magnetic stripe provided on a magnetic card, and passes through a position where the magnetic stripe acts on one of the two main magnetic poles. 4. The magnetic recording apparatus according to claim 1, wherein said main magnetic pole is provided substantially parallel or substantially perpendicular to a plane. 5. A magnetic sensor comprising: an excitation core portion on which an excitation coil is wound; and two detection core portions which are juxtaposed to sandwich the excitation core portion and have a gap on one side and wound around a detection coil. A magnetic flux passing through one of the two detection cores is changed by a magnetic medium on which the magnetic sensor unit is to be recorded, and the change in the magnetic flux is detected by the detection coil. A comparison unit for comparing the detection output with a reference level, wherein a recording current for the magnetic medium is determined based on an output of the comparison unit. 6. An integrated core body having two grooves formed on one side thereof, the excitation core formed at the center and the detection cores formed on both sides thereof, and wound around the two detection cores. 6. The magnetic recording apparatus according to claim 5, wherein a differential output is taken out by the two turned detection coils, and the differential output is compared with the reference level. 7. A magnetic sensor comprising: a detection core portion around which a detection coil is wound; and two excitation core portions which are juxtaposed to sandwich the detection core portion and have an air gap on one side and each of which is wound with an excitation coil. A magnetic flux passing through one of the two exciting cores, depending on the magnetic medium on which the magnetic sensor unit is to be recorded, and detecting the change in the magnetic flux with the detection coil. A comparison unit for comparing the detection output with a reference level, wherein a recording current for the magnetic medium is determined based on an output of the comparison unit. 8. A groove formed from one side surface of an integral core body, the detection core portion is formed at the center, and the excitation core portions are formed on both sides of the groove, and wound around the detection core portion. 8. The magnetic recording apparatus according to claim 7, wherein an output is taken out by the detection coil, and the output is compared with the reference level. 9. The magnetic medium is a magnetic stripe provided on a magnetic card, and the magnetic sensor portion is formed on or near the magnetic stripe of the magnetic card inserted from the card insertion slot. 9. The magnetic recording apparatus according to claim 5, wherein the magnetic recording apparatus is provided at a position outside a data track to be read.