JPH11238203A - Magnetic recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set an optimum recording current by detecting the magnetic permeability of the recording magnetic layer formed on a record medium and setting the recording current of a magnetic head to the recording current for magnetic permeability of the detected recording magnetic layer based on the output to judge the actual value of the coercive force of the medium in a short time without necessitating a discriminating mark. SOLUTION: In the case of performing a recording to a record medium and the reproducing of the medium, when the record medium is inserted from a port 19 to a magnetic recording device 9, an inserting sensor detects it to actuate a prehead 26 and a sensing sensor 1. The head 26 reads out magnetic data of the recording magnetic layer of the medium to judge whether the medium is at a prescribed position or not and whether it is a normal medium or not and it is inserted in a correct direction or not. When the read data are normal, the medium is transported to the inner part by actuating a driving motor and an exciting current is impressed on a coil by actuating an exciting circuit. Since a magnetic flux is guided to the medium through the recording magnetic layer and it is returned to the exciting coil, the leakage of the magnetic flux generated from the coil is made to be small.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording apparatus for writing magnetic data on a magnetic stripe such as a magnetic card or a passbook. More specifically, the present invention relates to a magnetic recording apparatus that automatically determines the level of coercive force of a magnetic stripe and switches a recording current.

[0002]

2. Description of the Related Art In a magnetic card, a passbook, or the like, which is a recording medium used in a conventional magnetic recording apparatus, the coercive force of a magnetic stripe is constant. However, in recent years, there has been a tendency to increase the coercive force of the magnetic stripe. This is because the high coercive force stripe can improve the recording density and the SN ratio of the signal as compared with the low coercive force stripe. For example, there is a movement to switch a low coercive force card having a coercive force of 300 Oe to a high coercive force card having a coercive force of 2750 Oe. For this reason, in the transition period of switching, both the low coercive force card and the high coercive force card may be used simultaneously.

When writing magnetic data to magnetic cards having different coercive forces, an appropriate read output cannot be obtained unless an appropriate recording current is set in accordance with the coercive force. Therefore, in response to the diversification and diversification of such recording media, the recording current of the magnetic head is changed on the magnetic recording device side according to the coercive force of the recording medium, so that the maximum output and the maximum output of the used recording medium are obtained. It is desired that a magnetic recording apparatus be provided with a function of determining the coercive force of a recording medium so that an SN ratio can be obtained.

As one method of determining the coercive force of a recording medium by a magnetic recording apparatus, recording current values having different magnitudes corresponding to a plurality of types of coercive forces of a recording medium that can be used are output, and each recording is performed. In some cases, a current value at which proper reading is performed by sequentially performing recording and reproduction with a current is set as an optimum current value.

As another discrimination method, there is a method of detecting a discrimination mark or the like formed on a case or the like of a recording medium (for example, a magnetic card itself) by using various sensors.

[0006]

However, in the above-described method of switching the recording current value and switching the recording / reproducing to make the discrimination, the recording / reproducing is performed with a plurality of recording currents in order to set the optimum current value every time a recording medium is inserted. Since it needs to be performed, the processing takes a long time. Also, in the method of discriminating using a discrimination mark formed on a recording medium, discrimination marks cannot be formed on all commodities of a magnetic recording product without a unified standard, for example, some computer-related magnetic recording products, etc. I can't get it.

Further, in any of the above-mentioned methods, only the type of coercive force of the recording medium can be determined, and the recording current is selected from several types set in advance.
Even if the recording current is slightly different due to the difference in thickness of the magnetic material, the difference in the thickness of the base material, the difference in the thickness of the media protection material, etc. due to the difference in the maker of the recording medium, it can cope with these slight differences As a result, the recording current cannot be finely adjusted.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic recording apparatus capable of determining an actual value of coercive force of a recording medium to be used in a short time without using a distinguishing mark and setting an optimum recording current. And

[0009]

In order to achieve the above object, a first aspect of the present invention is a magnetic recording apparatus for recording magnetic data on a recording medium by using a magnetic head. A detection sensor for detecting magnetic susceptibility is provided, and the recording current of the magnetic head is set to the detected recording current for the magnetic permeability of the recording magnetic layer based on the output of the detection sensor.

Therefore, since the recording current of the magnetic head is set based on the output of the detection sensor according to the magnetic permeability of the recording magnetic layer, an optimum current is set as compared with the method of setting the optimum current by switching the recording current and recording / reproducing. The time required for setting the recording current can be reduced. Also, since the detection sensor outputs according to the magnitude of the magnetic permeability of the recording magnetic layer, the set value of the recording current can be set to an optimum value according to the actual recording magnetic layer of the recording medium. Further, since the detection sensor detects the magnetic permeability of the recording magnetic layer, there is no need to form a discrimination mark or the like on the recording medium.

Further, in the magnetic recording apparatus of the present invention, the detection sensor has a rod-shaped core whose tip is arranged to face the recording medium, and the excitation coil is wound around the rod-shaped core and passes through the rod-shaped core. A magnetic flux detection unit for detecting a change in magnetic flux is provided,
The recording current is set based on the output of the magnetic flux detector. Therefore, the magnetic flux generated by the exciting coil passes through the recording medium and this magnetic flux is detected by the magnetic flux detecting section, so that the output of the magnetic flux detecting section changes depending on the difference in the magnetic permeability of the recording medium. For this reason, the recording current set by the output of the magnetic flux detector can be set to an optimum value according to the coercive force of the recording medium.

Further, in the magnetic recording apparatus according to the third aspect, the magnetic flux detecting unit is a detection coil wound around the rod-shaped core or a magnetoresistive element attached to the rod-shaped core. Therefore, the magnetic permeability of the recording medium can be detected by utilizing the effect of detecting the magnetic flux of the detection coil or the magneto-resistance effect element.

In the magnetic recording apparatus of the present invention, auxiliary cores for forming a magnetic flux path are integrally formed on both sides of the rod-shaped core with the rod-shaped core therebetween, and are separated between the rod-shaped core and the auxiliary core. Groove is formed. Therefore, since the magnetic flux emitted from the rod-shaped core by the excitation coil enters the auxiliary core, a large amount of magnetic flux can be passed through the rod-shaped core by reducing the magnetic flux leaking largely away from the rod-shaped core. Therefore, the sensitivity for detecting the magnetic permeability of the recording medium can be improved.

Further, in the magnetic recording apparatus according to the fifth aspect, the magnetic flux detecting section is a detecting coil wound around the rod-shaped core, and an auxiliary core for forming a magnetic flux path is formed on both sides of the rod-shaped core with the rod-shaped core. The detection coil is formed integrally with the rod-shaped core and the auxiliary core, and an excitation coil to which a high-frequency signal is applied is attached to the auxiliary core. Therefore, since the excitation coil and the magnetic flux detection unit can be arranged apart from each other, the sensitivity for detecting the magnetic permeability of the recording medium can be improved.

Further, the magnetic recording apparatus of the present invention has a magnetic permeability determining section for determining the magnetic permeability of the recording magnetic layer from the output of the detection sensor, and the recording current is switched by the output from the magnetic permeability determining section. I have to. Therefore, since the magnetic permeability is determined from the output of the detection sensor by the magnetic permeability determining unit, the coercive force of the captured recording medium can be determined with high accuracy. Therefore, the switching of the recording current can be performed strictly, and the accuracy of setting the recording current to the optimum value can be improved.

Further, in the magnetic recording apparatus of the present invention, the recording medium has an insertion slot for the recording medium, the recording medium is a magnetic card or a passbook, and the recording magnetic layer is a magnetic stripe formed on the magnetic card or the passbook. The detection sensor is provided to face the travel path of the recording medium.
Therefore, when recording and reproducing magnetic data on several types of magnetic cards or passbooks having different coercive forces of the magnetic stripe, it is possible to reduce the time required for setting an optimum recording current. Further, the set value of the recording current can be set to an optimum value in accordance with the actual detection result of the magnetic stripe. Further, it is not necessary to form a discrimination mark or the like on the magnetic card or passbook.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail based on an example of an embodiment shown in the drawings. As shown in FIGS. 1 to 7, a magnetic recording device 9 of the present embodiment records magnetic data on a recording medium 10 by a magnetic head 15. Here, the recording medium 10 is a magnetic card having a magnetic stripe as a recording magnetic layer. The magnetic recording device 9 is a card reader capable of recording and reproducing magnetic data on a magnetic card as shown in FIG. However, the recording medium 10 is not limited to a magnetic card, but may be a passbook or the like having a magnetic stripe.

As shown in FIGS. 1 and 2, the magnetic recording device 9 includes a detection sensor 1 for detecting the magnetic permeability of a recording magnetic layer formed on a recording medium 10 and a magnetic sensor based on the output of the detection sensor 1. The recording current of the head 15 is set to the recording current for the magnetic permeability of the detected recording magnetic layer. Magnetic recording device 9
Are a slot 19 for inserting the recording medium 10, a passage 20 for the recording medium 10 composed of a chassis or the like, a conveying roller 21 for conveying the recording medium 10 in the passage 20, and a conveying roller 21.
, A drive system 25 including a belt 23 and a pulley 24 for transmitting the power of the drive motor 22 to the drive motor 22, a magnetic head 15 for recording and reproducing magnetic data on and from the recording medium 10, The pre-head 26 disposed near the opening 19, the detection sensor 1 disposed adjacent to the pre-head 26, and the recording medium 10
An insertion sensor (not shown) for detecting that the recording medium 10 has been inserted and operating the pre-head 26 and the detection sensor 1, and a shutter 28 for preventing the recording medium 10 from entering the interior of the passage 20. Insertion port 19 of this magnetic recording device 9
The configuration of the motor 20, the path 20, the transport roller 21, the drive system 25, the drive motor 22, the magnetic head 15, and the pre-head 26 may be existing or new ones irrespective of the characteristic configuration of the invention. The detailed description of is omitted.

The pre-head 26 detects the presence or absence of a recording magnetic layer of the recording medium 10 inserted from the insertion port 19.
If it is determined that there is a recording magnetic layer, the drive motor 22 is driven and the transport roller 21 drives the recording medium 1.
Send 0 to the back. On the other hand, if the pre-head 26 determines that there is no recording magnetic layer, it is because the recording medium 10 is improper, or even if it is proper, the insertion direction is wrong, etc. Then, the shutter 28 is closed so that the recording medium 10 does not enter deeper than it.

The detection sensor 1 detects the magnetic permeability of the recording magnetic layer formed on the recording medium 10. This detection sensor 1
Are installed adjacent to the pre-head 26 along the width direction of the recording medium 10 in the transport direction. Therefore, immediately after the recording medium 10 is inserted through the insertion slot 19, the pre-head 26
And detection by the detection sensor 1 at the same time. Here, since the magnetic stripe as the recording magnetic layer is wide,
Even when the pre-head 26 and the detection sensor 1 are arranged in the width direction, the magnetic stripe can be simultaneously detected. For this reason, when the magnetic data of the recording magnetic layer of the recording medium 10 is about to disappear, the shutter 28 is closed without being detected as an appropriate recording medium 10 by the pre-head 26 alone. By the detection, it can be confirmed that the recording medium 10 is appropriate. Even if the recording medium 10 can properly record and reproduce magnetic data with the magnetic head 15,
This is because the recording magnetic layer may not be detected by the pre-head 26 because the medium insertion speed is too slow. Therefore,
The installation of the detection sensor 1 can prevent such a malfunction.

In this embodiment, the detection sensor is a pre-head 2
6, but is not limited to this, and may be installed near the magnetic head 15 as shown in FIG. That is, in this magnetic recording device 9 ′, since the detection sensor 1 is for setting the recording current of the magnetic head 15, if the magnetic permeability can be detected before the magnetic head 15 records the magnetic data on the recording medium 10, good. For this reason, the installation position of the detection sensor 1 is determined by the magnetic head 15
The position is not particularly limited as long as it is a position where magnetic permeability can be detected before magnetic data is recorded.

In the present embodiment, the pre-head 26 is provided alongside the detection sensor 1. However, the present invention is not limited to this, and the detection of the magnetic recording layer and the measurement of the magnetic permeability are performed using only the detection sensor 1 without the pre-head 26. Detection may be performed simultaneously.

As shown in FIG. 4, the detection sensor 1 has a rod-shaped core 3 whose tip is arranged to face the recording medium 10. The rod-shaped core 3 is provided with a detection coil 5 which is a magnetic flux detector for detecting a change in magnetic flux passing through the rod-shaped core 3. Auxiliary cores 7 for forming a magnetic flux path are formed integrally with the rod-shaped core 3 on both sides of the rod-shaped core 3 therebetween, thereby forming the core body 2. This detection sensor 1
Is made of a soft magnetic material such as fillite. In the present embodiment, a core having a bar shape and the leading end directed toward the recording medium 10 is arranged in a grid of 3 rows × 3 rows to form a so-called cross-girder shape.
The core of the book is an auxiliary core 7.

Further, between the rod-shaped core 3 and the auxiliary core 7, a groove 3 for separating the rod-shaped core 3 and the auxiliary core 7 is provided.
0 is formed. For this reason, the detection coil 5 is fitted in the groove 30 around the rod-shaped core 3. An exciting coil 6 is wound around the entire eight auxiliary cores 7. For this reason, since the detection coil 5 and the excitation coil 6 can be set apart from each other, the detection coil 5 and the excitation coil 6 are too close to each other, and the magnetic flux from the excitation coil 6 is
Can be prevented from being directly affected, and the sensitivity of the detection sensor 1 can be improved.

The smaller the width and the depth of the groove portion 30, the higher the sensitivity of the detection sensor 1 can be. On the other hand, if the width and the depth of the groove 30 are too small, the detection coil 5 cannot be wound. Therefore, the width and the depth of the groove 30 are preferably 2 mm or less, more preferably 0.5 mm or less, and most preferably about 0.3 mm. Further, the groove 30 may be filled with a resin or the like for preventing cracking of the core chip.

Also, the exciting coil 6
Is larger than the distance from the tip of the rod-shaped core 3 to the detection coil 5. That is, the detection coil 5 and the exciting coil 6 are arranged in a step shape. For this reason, in a portion of the detection coil 5 that does not overlap with the excitation coil 6, it is possible to suppress the direct influence of the magnetic flux from the excitation coil 6, so that the sensitivity of the detection sensor 1 can be increased.

Here, in order to make the distance from the tip of the rod-shaped core 3 to the exciting coil 6 larger than the distance from the tip of the rod-shaped core 3 to the detection coil 5, the width of each of the coils 5, 6 is made equal. A structure in which the turning position is shifted up and down, or a structure in which the widths of the coils 5 and 6 are different may be adopted.

When a current is applied to the exciting coil 6, a magnetic flux is generated from the rod-shaped core 3 and the auxiliary core 7 to form an AC magnetic field. The magnetic flux passing through the rod-shaped core 3 is detected by the detection coil 5. Then, the recording medium 1 is located at a position facing the tip of the rod-shaped core 3 and the auxiliary core 7.
When the 0 recording magnetic layer is located, the magnetic flux flows through the recording magnetic layer, and the magnetic flux detected by the detection coil 5 increases. By reading this change in magnetic flux, the transmittance of the recording magnetic layer can be detected.

In the present embodiment, the distance from the tip of the rod-shaped core 3 to the exciting coil 6 is larger than the distance from the tip of the rod-shaped core 3 to the detection coil 5. However, the present invention is not limited to this. May be made equal to each other between the coils 5 and 6. Also in this case, the magnetic flux from the excitation coil 6 can be detected by the detection coil 5, so that the transmittance of the recording magnetic layer can be detected.

Further, based on the output of the detection sensor 1,
The permeability determining unit 31 sets the value suitable for the recording magnetic layer of the recording medium 10 in which the recording current of the magnetic head 15 is taken.
The magnetic permeability determining unit 31 calculates the magnetic permeability of the recording magnetic layer from the output of the signal detection circuit 27 for extracting the output from the detection sensor 1 as shown in FIG. And a control means 32 comprising a microcomputer for setting the recording current.

The control means 32 also controls an excitation circuit 33 for applying an excitation coil 6 and a recording current circuit 34 for applying a recording current to the magnetic head 15. The control means 3
Reference numeral 2 denotes a microcomputer provided with a central processing unit, a recording device of RAM and ROM, an input / output device, and the like, but is not limited thereto, and may be a sequencer circuit that performs a predetermined operation. The control means 32 controls the signal detection circuit 27
The magnitude of the recording current of the magnetic head 15 is set to a value suitable for the recording magnetic layer of the recording medium 10 based on the magnitude of the signal from the recording medium 10.

The signal detection circuit 27 is, as shown in FIGS. 5 to 7, an amplifier 11 for amplifying a detection current from the detection coil 5.
And a detection circuit 12 for half-wave rectifying the output from the amplifier 11
And a peak hold circuit 13 for taking the peak value of the half-wave rectified signal and detecting the envelope, and an AD converter 29 for digitally converting the envelope, which is an analog signal. Note that FIG. 5 shows a block diagram of the signal detection circuit 27, and FIGS. 6 and 7 each show a part of the signal detection circuit 27 with a different circuit example. In the present embodiment, the output from the peak hold circuit is converted by the AD converter, but the present invention is not limited to this, and a comparator that performs the same operation may be used.

Further, the excitation circuit 33 includes an excitation drive circuit 35 for generating an excitation current in response to an excitation start signal 41 from the control means 32, and a high-frequency oscillation signal 14 for the excitation current.
And an oscillator 36 for providing In FIG.
Is a diode for absorbing the back electromotive force generated by the exciting coil 6, and constitutes a protection circuit.

On the other hand, the recording current circuit 34
And a switching circuit 38 for receiving a recording current switching signal 39 from the control means 32 and switching the recording current in the writing circuit 37.

The operation of the magnetic recording device 9 will be described below. When performing recording or reproduction on the recording medium 10, the recording medium 10 is inserted into the magnetic recording device 9 from the insertion slot 19 as shown in FIGS. 1 and 2. Then, the recording medium 10
Is detected by the insertion sensor, and the pre-head 26 and the detection sensor 1 are operated. The pre-head 26 is a recording medium 1
By reading the magnetic data of the recording magnetic layer of No. 0, it is determined whether or not the recording magnetic layer is present at a predetermined position of the recording medium 10, that is, whether or not the recording medium 10 is correct and inserted in the correct direction. Detect. Here, if the reading cannot be performed normally by the pre-head 26, it is determined that there is an abnormality in the recording medium 10 and the shutter 28 is closed so that the recording medium 10 does not enter deeper. If the reading can be normally performed by the pre-head 26, the normal recording medium 1
0 is determined to be inserted in a normal direction,
Is operated to convey the recording medium 10 to the back.

At the same time as reading by the pre-head 26, the detection sensor 1 is operated. The operation of the detection sensor 1 will be described with reference to the flowchart shown in FIG. First, when the insertion sensor is turned on, the excitation start signal 4
1 transmits (step 101). And the excitation circuit 3
3 operates to apply an exciting current to the exciting coil 6. A magnetic flux is generated from the exciting coil 6 and passes through the recording magnetic layer.

Here, since the magnetic flux is guided through the recording magnetic layer and returned to the exciting coil 6 again, the leakage of the magnetic flux generated from the exciting coil 6 is reduced. For this reason, the output from the detection coil 5 becomes larger as compared with the case where there is no recording magnetic layer. When the recording magnetic layer has a low coercive force, the magnetic flux easily passes therethrough, so that the output from the detection coil 5 greatly increases. On the other hand, when the recording magnetic layer has a high coercive force, the output from the detection coil 5 increases only slightly because the magnetic flux does not easily pass through. Thus, the magnetic permeability of the recording magnetic layer can be measured based on the magnitude of the output from the detection coil 5.

Then, the output from the detection coil 5 is digitally converted by the signal detection circuit 27 to obtain magnetic permeability (step 102). If the value of the magnetic permeability is obtained, the activation of the excitation sensor 41 is stopped because the operation of the detection sensor 1 is unnecessary (step 103). The value of the magnetic permeability is compared with a threshold value preset in the control circuit (step 104). If the magnetic permeability is smaller than the threshold value, it is determined that the recording magnetic layer has a high coercive force (step 105). Therefore, the recording current is set to a high value (Step 106). On the other hand, if the magnetic permeability is larger than the threshold value, it is determined that the recording magnetic layer has a low coercive force (step 107). Therefore, the recording current is set to a low value (Step 108).

In this embodiment, only one threshold value is set and two types of recording currents are set depending on whether the threshold value is larger or smaller. However, the present invention is not limited to this. For example, two threshold values may be set. Alternatively, three types of recording currents may be set by comparing the magnitude with these. If the threshold value is increased, the recording current can be further increased. For this reason,
The same number of recording currents corresponding to the types of coercive force of the recording medium 10 to be used can be set.

Further, in the present embodiment, the recording current is selectively switched depending on whether the recording current is larger or smaller than the threshold value. However, the present invention is not limited to this, and the recording current may be changed according to the magnetic permeability obtained by the detection sensor 1. The recording current may be set individually. In this case, even if the optimum recording current is slightly different due to the difference in thickness of the magnetic material due to the difference in the maker of the recording medium 10, the difference in the thickness of the base material, the difference in the thickness of the medium protection material, etc. The recording current can be finely adjusted according to the difference.

The magnitude of the set recording current is used as a recording current switching signal 39 by the control means 32 to switch the switching circuit 3.
8 and is set. When recording on the recording medium 10, the write circuit 37 applies a recording current to the magnetic head 15 based on the value of the recording current set in the switching circuit 38 (step 109). Thereby, magnetic data can be recorded with a magnitude of the recording current suitable for the coercive force of the recording magnetic layer of the recording medium 10. After recording the magnetic data, the drive motor 22 rotates in the reverse direction and the recording medium 10 is ejected from the insertion slot 19.

As described above, according to the magnetic recording device 9 of the present embodiment, the detection sensor 1 corresponding to the magnetic permeability of the recording magnetic layer
Since the recording current of the magnetic head 15 is set based on the output, the time required for setting the optimum recording current can be reduced as compared with the method of setting the optimum current by switching the recording current and performing recording and reproduction. In addition, since the detection sensor 1 outputs according to the magnitude of the magnetic permeability of the recording magnetic layer, the set value of the recording current can be set to an optimal value according to the actual recording magnetic layer of the recording medium 10. . Therefore, it is possible to improve the recording accuracy of the magnetic data. Further, since the detection sensor 1 detects the magnetic permeability of the recording magnetic layer, it is not necessary to form a discrimination mark or the like on the recording medium 10. Therefore, high-precision magnetic data can be recorded in a short time even on a recording medium 10 that does not have a unified standard.

In addition, in the detection sensor 1 of the present embodiment, the auxiliary cores 7 for forming the magnetic flux passages are formed integrally with the rod-shaped core 3 on both sides of the rod-shaped core 3 therebetween. The magnetic flux from the core 3 enters the auxiliary core 7. For this reason, a large amount of magnetic flux can be made to pass through the rod-shaped core 3 by reducing the magnetic flux leaking largely away from the rod-shaped core 3, so that the sensitivity of detecting the magnetic permeability of the recording medium 10 can be improved.

Further, in the detection sensor 1 of the present embodiment,
Since the detection coil 5 and the excitation coil 6 are disposed apart from each other, it is possible to prevent that the detection coil 5 and the excitation coil 6 are too close to each other and the magnetic flux from the excitation coil 6 directly affects the detection coil 5. As a result, the sensitivity of the detection sensor 1 can be improved.

In the detection sensor 1 of the present embodiment, the distance from the tip of the rod-shaped core 3 to the exciting coil 6 is larger than the distance from the tip of the rod-shaped core 3 to the detection coil 5. In a portion that does not overlap with the exciting coil 6, it is possible to suppress direct influence of the magnetic flux from the exciting coil 6 and increase the sensitivity of the detection sensor 1.

Although the above embodiment is an example of a preferred embodiment of the present invention, the present invention is not limited to this embodiment, and various modifications can be made without departing from the gist of the present invention. For example, in the present embodiment, the arrangement of the cores of the detection sensor 1 is a double girder having eight auxiliary cores 7 around the rod-shaped cores 3 as shown in FIG. 4, but is not limited thereto, as shown in FIG. Alternatively, a cylindrical auxiliary core 7 may be integrally arranged around a cylindrical rod-shaped core 3.
In this case, the detection coil 5 is wound around the rod-shaped core 3 and the excitation coil 6 is wound around the auxiliary core 7.
Also with this detection sensor 1, the magnetic flux emitted from the rod-shaped core 3 by the excitation coil 6 enters the auxiliary core 7 and reduces the magnetic flux leaking from the rod-shaped core 3, so that more magnetic flux can pass through the rod-shaped core 3. The sensitivity for detecting the magnetic permeability of the recording medium 10 can be improved. In addition, since the detection coil 5 and the excitation coil 6 are disposed apart from each other, the detection coil 5 and the excitation coil 6 are so close that the magnetic flux from the excitation coil 6 directly affects the detection coil 5. By preventing the detection, the sensitivity of the detection sensor 1 can be improved.

The detection sensor 1 according to the above-described embodiment
In the above, the auxiliary core 7 is arranged around the rod-shaped core 3,
The present invention is not limited to this, and may have a so-called E-shape in which a pair of auxiliary cores 7 are integrally arranged on both sides of the rod-shaped core 3 as shown in FIG. In this case, the detection coil 5 is wound around the rod-shaped core 3 and the excitation coil 6 is wound around the auxiliary core 7. According to this detection sensor 1 as well, the magnetic flux emitted from the rod-shaped core 3 by the excitation coil 6 enters the auxiliary core 7 and reduces the magnetic flux leaking from the rod-shaped core 3 to reduce the rod-shaped core 3
Therefore, the sensitivity of detecting the magnetic permeability of the recording medium 10 can be improved. In addition, since the detection coil 5 and the excitation coil 6 are disposed apart from each other, it is assumed that the detection coil 5 and the excitation coil 6 are too close to each other and the magnetic flux from the excitation coil 6 directly affects the detection coil 5. By preventing the detection, the sensitivity of the detection sensor 1 can be improved.

Further, a guard member 42 may be provided around the detection sensor 1 shown in FIG. 10 as shown in FIG.
The guard member 42 has a sensor hole 43 from which the ends of the cores 3 and 7 of the detection sensor 1 are exposed, and a guide surface 44 through which the recording medium 10 is guided. The tip of each of the cores 3 and 7 of the detection sensor 1 is installed at a lower position recessed from the guide surface 44. Further, it is preferable to fill the space between the guard member 42 and the core body 2 with a resin or the like to prevent the core body 2 from cracking. According to the detection sensor 1, when the recording medium 10 is guided and conveyed by the guide surface 44, the recording medium 10
Is detected by the detection sensor 1 in a non-contact manner. For this reason,
Wear due to contact between the cores 3 and 7 and the recording medium 10 can be suppressed.

Further, in the detection sensor 1 of each of the above-described embodiments, the distal end portions of the rod-shaped core 3 and the auxiliary core 7 have a planar shape parallel to the recording medium 10, but the present invention is not limited to this, and as shown in FIG. For example, the tip portions of the rod-shaped core 3 and the auxiliary core 7 of the E-shaped core can have the highest curved surface at the center along the conveying direction of the recording medium 10 (indicated by an arrow in the drawing). According to the detection sensor 1, since the contact between the rod-shaped core 3 and the recording medium 10 can be ensured, the detection accuracy of the detection sensor 1 can be improved. Moreover, when the recording medium 10 approaches the detection sensor 1, the leading edge of the recording medium 10 is guided by the leading end surfaces of the cores 3 and 7, thereby preventing the recording medium 10 from colliding with the side surface of the auxiliary core 7. Therefore, the conveyance of the recording medium 10 can be performed smoothly.

Further, the detection sensor 1 of each of the above embodiments
In this embodiment, the exciting coil 6 is directly wound around the auxiliary core 7 and fixed. However, the present invention is not limited to this, and a step 17 is formed on the side of the auxiliary core 7 as shown in FIG. May be supported. According to this, the excitation coil 6 can be easily supported.

FIG. 14 shows an outline of a manufacturing process of the detection sensor 1 shown in FIG. First, the groove 18a and the step 18b are machined into the ferrite block 18 shown in (a) to obtain the state shown in (b), and the ferrite block 18 is cut into an appropriate thickness and shown in (c). Thus, the core body 2 is manufactured. The groove 18a becomes the groove 30 for installing the detection coil 5, and the step 18b becomes the step 17 for installing the exciting coil 6. Then, as shown in FIG.
And the exciting coil 6 are installed.

As shown in FIG. 15, a return path core 8 may be provided outside the auxiliary core 7 of the E-type detection sensor 1. In this case, the magnetic flux formed outside the excitation coil 6 is guided by the return path core 8, so that the leakage of the magnetic flux can be reduced and the sensitivity of the detection sensor 1 can be further improved.

In the detection sensor 1 of each of the above-described embodiments, the exciting coil 6 is wound around the outer periphery of the auxiliary core 7. However, the present invention is not limited to this, and both the detecting coil 5 and the exciting coil 6 are connected as shown in FIG. It may be wound around the rod-shaped core 3. In addition, in the detection sensor 1 of each embodiment described above, the exciting coil 6 is wound around the outer periphery of the auxiliary core 7 and the detection coil 5 is wound around the rod-shaped core 3. However, the present invention is not limited to this.
May be wound around the rod-shaped core 3 and the detection coil 5 may be wound around the outer periphery of the auxiliary core 7.

Further, in the detection sensor 1 of each of the above-described embodiments, the detection coil 5 is used as the magnetic flux detection unit. However, the present invention is not limited to this, and may be a magnetoresistance effect element.
In this case, the magnetic permeability of the recording medium 10 can be detected by detecting the magnetic flux using the magnetoresistive element.

In the magnetic recording device 9 of each of the above-described embodiments, a magnetic card is used as the recording medium 10. However, the present invention is not limited to this. For example, a passbook having a magnetic stripe may be used. Also in this case, the recording current of the magnetic head 15 is set based on the output of the detection sensor 1 according to the magnetic permeability of the recording magnetic layer. The time required for setting a proper recording current can be reduced. In addition, since the detection sensor 1 outputs according to the magnitude of the magnetic permeability of the recording magnetic layer, the set value of the recording current can be set to an optimal value according to the actual recording magnetic layer of the recording medium 10. . Therefore, it is possible to improve the recording accuracy of the magnetic data. Further, since the detection sensor 1 detects the magnetic permeability of the recording magnetic layer, it is not necessary to form a discrimination mark or the like on the recording medium 10. For this reason, it is possible to record magnetic data with high accuracy in a short time even for a passbook without a unified standard.

Further, the detection sensor 1 of each of the above-described embodiments is used.
Is provided in the ejection part of the stocker of the card issuing machine, and before the magnetic card is ejected from the stocker and conveyed to the data recording part, the magnetic permeability of the magnetic stripe of the magnetic card is detected and the data is recorded in the data recording part. The current may be set or it may be determined whether the magnetic card selected from the stocker is appropriate. With this, even if the wrong magnetic card is stocked in the stocker, it is possible to check before writing the magnetic data to obtain an appropriate recording current, or to stop issuing the card if the magnetic card is incorrect. it can. As a result, it is possible to prevent unauthorized issuance of the magnetic card.

[0057]

As is apparent from the above description, according to the magnetic recording apparatus of the first aspect, the recording current of the magnetic head is set based on the output of the detection sensor according to the magnetic permeability of the recording magnetic layer. The time required for setting the optimum recording current can be reduced as compared with the method of setting the optimum current by switching the recording current and recording / reproducing. Also, since the detection sensor outputs according to the magnitude of the magnetic permeability of the recording magnetic layer, the set value of the recording current can be set to an optimum value according to the actual recording magnetic layer of the recording medium. Therefore, it is possible to improve the recording accuracy of the magnetic data. further,
Since the detection sensor detects the magnetic permeability of the recording magnetic layer, there is no need to form a discrimination mark or the like on the recording medium. For this reason,
High-precision recording of magnetic data can be performed in a short time even on a recording medium that does not have a unified standard.

According to the magnetic recording apparatus of the second aspect,
Since the magnetic flux generated by the exciting coil passes through the recording medium and is detected by the magnetic flux detection unit, the output of the magnetic flux detection unit changes due to the difference in the magnetic permeability of the recording medium. For this reason, the recording current set by the output of the magnetic flux detector can be set to an optimum value according to the coercive force of the recording medium.

Further, in the magnetic recording apparatus according to the third aspect, the magnetic flux detector is a detection coil wound around a rod-shaped core or a magnetoresistive effect element attached to the rod-shaped core. The magnetic permeability of the recording medium can be detected using the effect of detecting the magnetic flux of the resistance element.

According to the magnetic recording apparatus of the fourth aspect,
Since the magnetic flux coming out of the rod-shaped core by the exciting coil enters the auxiliary core, it is possible to reduce the magnetic flux leaking largely away from the rod-shaped core and to pass a large amount of magnetic flux through the rod-shaped core. Therefore, the sensitivity for detecting the magnetic permeability of the recording medium can be improved.

Further, in the magnetic recording apparatus according to the fifth aspect, the magnetic flux detecting section is a detecting coil wound around a rod-shaped core, and an auxiliary core for forming a magnetic flux passage is formed on both sides of the rod-shaped core. It is formed integrally, the detection coil is arranged between the rod-shaped core and the auxiliary core, and the excitation coil to which a high-frequency signal is applied is attached to the auxiliary core. The sensitivity for detecting the magnetic permeability of the recording medium can be improved.

Further, according to the magnetic recording apparatus of claim 6,
Since the magnetic permeability is determined from the output of the detection sensor by the magnetic permeability determining unit, the coercive force of the captured recording medium can be determined with high accuracy. Therefore, the switching of the recording current can be performed strictly, and the accuracy of setting the recording current to the optimum value can be improved.

Further, in the magnetic recording apparatus of the present invention, the recording medium has an insertion slot for the recording medium, the recording medium is a magnetic card or a passbook, and the recording magnetic layer is a magnetic stripe formed on the magnetic card or the passbook. The detection sensor is provided to face the running path of the recording medium, so when recording and reproducing magnetic data on several types of magnetic cards or passbooks with different coercive forces of the magnetic stripe, it is possible to set the optimum recording current. The required time can be reduced.
Further, the set value of the recording current can be set to an optimum value in accordance with the actual detection result of the magnetic stripe. Further, it is not necessary to form a discrimination mark or the like on the magnetic card or passbook.

[Brief description of the drawings]

FIG. 1 is a side view showing an outline of a magnetic recording apparatus of the present invention.

FIG. 2 is a perspective view showing the entire magnetic recording apparatus.

FIG. 3 is a side view showing another embodiment of the magnetic recording device.

FIG. 4 is a perspective view showing a detection sensor.

FIG. 5 is a block diagram showing an outline of a circuit for operating a detection sensor and a magnetic head.

FIG. 6 is a circuit diagram showing one embodiment of a signal detection circuit.

FIG. 7 is a circuit diagram showing another embodiment of the signal detection circuit.

FIG. 8 is a flowchart showing a procedure for setting a recording current.

FIG. 9 is a perspective view showing a cylindrical embodiment of the detection sensor.

FIG. 10 is a perspective view showing an E-shaped embodiment of the detection sensor.

FIG. 11 is a perspective view showing another embodiment of the E-type detection sensor.

FIG. 12 is a perspective view showing an embodiment provided with a guard member of the detection sensor.

FIG. 13 is a perspective view showing an embodiment having a step portion of the detection sensor.

14 (a) is a perspective view of a ferrite block, FIG. 14 (b) is a perspective view of a state where grooves and steps are formed in the ferrite block, and FIG. 14 (c) is a view schematically showing a manufacturing process of the detection sensor shown in FIG. FIG. 4 is a perspective view of a core body obtained by cutting a ferrite block, and FIG. 4D is a perspective view showing a state in which a detection coil and an exciting coil are installed on the core body.

FIG. 15 is a perspective view showing an embodiment having a return path core of the detection sensor.

FIG. 16 is a perspective view showing another embodiment of the detection sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Detection sensor 3 Bar-shaped core 5 Detection coil (magnetic flux detection part) 6 Excitation coil 7 Auxiliary core 9 Magnetic recording device 10 Recording medium 15 Magnetic head 19 Insertion opening 20 Passage 30 Groove part 31 Permeability determination part

Claims (7)

[Claims] In a magnetic recording apparatus for recording magnetic data on a recording medium by a magnetic head, a detection sensor for detecting the magnetic permeability of a recording magnetic layer formed on the recording medium is provided, and based on an output of the detection sensor, A magnetic recording apparatus, wherein a recording current of a magnetic head is set to a detected recording current for the magnetic permeability of the recording magnetic layer. 2. The sensor according to claim 1, wherein the detection sensor has a rod-shaped core whose front end is arranged to face the recording medium. The rod-shaped core is wound with an exciting coil and detects a change in magnetic flux passing through the rod-shaped core. 2. A magnetic flux detector, wherein the recording current is set by an output of the magnetic flux detector.
The magnetic recording device according to the above. 3. The magnetic recording apparatus according to claim 2, wherein the magnetic flux detector is a detection coil wound around the rod-shaped core or a magnetoresistive element attached to the rod-shaped core. 4. An auxiliary core for forming a magnetic flux path is integrally formed on both sides of the rod-shaped core with the rod-shaped core therebetween, and a separation groove is formed between the rod-shaped core and the auxiliary core. Claim 2 or Claim 3 characterized by the following.
The magnetic recording device according to the above. 5. The magnetic flux detection unit is a detection coil wound around the rod-shaped core, and an auxiliary core for forming a magnetic flux path is integrally formed on both sides of the rod-shaped core with the rod-shaped core, 3. The magnetic recording apparatus according to claim 2, wherein the detection coil is arranged between the rod-shaped core and the auxiliary core, and an excitation coil to which a high-frequency signal is applied is attached to the auxiliary core. 6. A magnetic recording medium according to claim 1, further comprising a magnetic permeability determining unit for determining a magnetic permeability of said recording magnetic layer from an output of said detection sensor, wherein a recording current is switched by an output from said magnetic permeability determining unit. The magnetic recording apparatus according to any one of claims 1 to 5. 7. It has an insertion port for the recording medium,
The recording medium is a magnetic card or passbook, the recording magnetic layer is a magnetic stripe formed on the magnetic card or passbook, and the detection sensor is provided to face a traveling path of the recording medium. The magnetic recording apparatus according to claim 1, wherein