JP2001093106A - Magnetic recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep the information recorded with high density in the semi- permanently reproducible condition by recording again before the unfailing reproduction becomes difficult due to the decrease of the existing magnetization of the recording with the lapse of time. SOLUTION: The device is constituted in such a manner that the recorded information is periodically and automatically copied by adding a timer, a cache memory and a copy control circuit to a conventional magnetic disk device, or the information elapsed for specified time or longer from the final recording day is automatically copied by adding the cache memory, the copy control circuit, a retrieval control circuit, a 1st timer and a 2nd timer, or a reference signal is preliminarily recorded to periodically measure the reproduced output by adding the cache memory, copy control circuit, timer and reproduced output detecting circuit, then the recorded information is automatically copied when this output is equal to a reference value or lower, or the temperature in the device is measured by a temperature sensor 18, then the information is automatically copied with a period shorter than that at the ambient temperature when the output is equal to the reference value or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for maintaining the reliability of a magnetic recording / reproducing apparatus, and more particularly to a method capable of semi-permanently maintaining high-density recorded information. And a magnetic recording and reproducing apparatus.

[0002]

2. Description of the Related Art FIG. 5 is a schematic diagram showing a conventional example of a partial configuration of a control system of a magnetic disk drive and a control system of a host computer. In the figure, reference numeral 25 denotes a control circuit system of the magnetic disk drive, and reference numeral 21 denotes a part of the control system of the host computer.
5 is an interface unit 4, a read / write control unit 5,
The head 4 comprises a head positioning control unit 6 and a spindle motor control unit 7, and the interface unit 4 includes a read / write control unit 5, a head positioning control unit 6, a spindle motor control unit 7, and It is connected to the magnetic disk device interface section 11 in the host computer 21, the read / write control section 5 is connected to the magnetic head 8, the head positioning control section 6 is connected to the head carriage 9, and the spindle motor is connected. The motor control units 7 are connected to the spindle motor 10, respectively. An instruction from the host computer 21 is sent from the magnetic disk device interface unit 11 in the host computer 21 to the interface of the magnetic disk device control system 25.
The information is sent to the storage unit 4 to record / reproduce information. Record /
To perform reproduction, first, the magnetic disk is rotated by the spindle motor 10, then the magnetic head 8 is moved to a desired track by the head carriage 9, and then the formation and detection of recording magnetization are performed by the magnetic head 8. Do. These operations are controlled by a spindle motor control unit 7, a head positioning control unit 6, and a read / write control unit 5, respectively. As for the magnetic disk device having the above-described configuration, for example, all of the transistor technology special hard disk and the SSI application technology are described in pp. 139-214. 8 (See-K-Publisher).

In a conventional magnetic disk device, once recorded information is not copied unless a human specifies otherwise. This is because magnetic recording has been considered to be a recording method capable of semi-permanently retaining information once recorded as recording magnetization.

However, if the diameter of magnetic particles is reduced or the medium is made thinner in order to increase the areal recording density in magnetic recording, the recording magnetization of each bit may decrease over time due to the effects of thermal fluctuations. It has become clear that it is particularly remarkable at high temperatures. This is described in IEICE Technical Report M-R 94-105 pp. 25-30 (March 1995). Further, in a medium using a soft magnetic underlayer, the reproduction output may decrease with the passage of time.
995).

[0005] When the recording magnetization decreases, there is a possibility that information cannot be correctly reproduced, and thus a problem arises in that the reliability of the recording apparatus is impaired.

As a means for maintaining or improving the reliability of a magnetic disk drive, a function (smart) of predicting a failure by performing a self-diagnosis has been proposed. This is a method in which a warning is issued to the host when the number of seek errors or retries during normal use exceeds a reference value. For this, a data request alert (1) is used.
April 17, 995). However, in this method, a warning is issued after an abnormality has begun to occur during normal use, and there is a risk that it is too late to reliably recover when the recording magnetization of the medium has decreased.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art, to maintain information recorded at high density in a semi-permanently reproducible state, and to provide a magnetic recording / reproducing apparatus. The point is to maintain reliability.

[0008]

To achieve the above object, a magnetic recording / reproducing apparatus according to the present invention comprises at least one magnetic recording medium, a magnetic recording medium drive for driving the magnetic recording medium, and A magnetic head for recording / reproducing information on / from the magnetic recording medium, a magnetic head driving unit for driving the magnetic head, processing a recording signal to the magnetic head and a reproduction signal from the magnetic head, and driving the magnetic recording medium Unit, a clock circuit, a cache memory, and a copy control circuit are added to a magnetic recording / reproducing apparatus having a control circuit system for processing a control signal of a magnetic head driving section, and a magnetic recording / reproducing apparatus is already recorded in the magnetic recording / reproducing apparatus. It has a function to periodically and automatically copy existing information. That is, in the embodiment shown in FIG.
A face unit 4, a read / write control unit 5, a head positioning control unit 6, a spindle motor control unit 7, and a read / write control unit respectively connected to the interface unit 4. A magnetic disk drive having at least a magnetic head 8 connected to a magnetic head 5, a head carriage 9 connected to a head positioning control unit 6, and a spindle motor 10 connected to a spindle motor control unit 7, , A clock device 1, a cache memory 2, and a copy control circuit 3. The copy control circuit 3 includes a clock device 1, a cache memory 2, an interface unit 4, a read / write control unit 5, a head positioning. The timer unit 1 is connected to the control unit 6 and the spindle motor control unit 7 and periodically issues a signal for activating the copy control circuit 3 from the clock unit 1, and the signal is already recorded in the magnetic disk unit. After temporarily stored in the cache memory 2 are sequentially read data stored on the, it is characterized in that it has means for performing automatically recorded, i.e. copying back the magnetic disk.

Further, the magnetic recording / reproducing apparatus according to the present invention comprises:
At least one magnetic recording medium, a magnetic recording medium driving unit for driving the magnetic recording medium, a magnetic head for recording / reproducing information on / from the magnetic recording medium, a magnetic head driving unit for driving the magnetic head, A magnetic recording / reproducing apparatus having a control circuit system for processing a recording signal to the head and a reproduction signal from the magnetic head and for processing a control signal of the magnetic recording medium driving section and the magnetic head driving section; , A copy control circuit, and a search control circuit are added, and among the information already recorded in the magnetic recording / reproducing apparatus, information that has passed a certain time from the last recording date when any information is recorded is automatically read. It is characterized by having means for copying.

That is, in the embodiment shown in FIG.
An interface unit 4, a read / write control unit 5, a head positioning control unit 6, and a spindle motor control unit 7 connected to the interface unit 4, respectively; A magnetic head 8 connected to the control unit 5, a head carriage 9 connected to the head positioning control unit 6,
Spindle motor connected to spindle motor control unit 7
A magnetic disk drive having at least a cache memory 2, a copy control circuit 3, a search control circuit 12, a first clock device 13, and a second clock device 14, wherein the copy control circuit 3 A cache memory 2, an interface unit 4, a read / write control unit 5,
A head positioning controller 6, a spindle motor controller 7,
And the search control circuit 12. The search control circuit 12 further includes an interface unit 4, a read /
The first timer 1 is connected to the write controller 5, the head positioning controller 6, the spindle motor controller 7, the first timer 13, and the second timer 14, respectively.
3, a signal for activating the search control circuit 12 is periodically issued, and by referring to the current date output from the second time measuring device 14, of the information already recorded in the magnetic disk device, Information that has passed a predetermined time or more from the recording date is retrieved, the information name is transferred to the copy control circuit 3, the corresponding information is sequentially reproduced, temporarily stored in the cache memory 2, and then automatically recorded on the magnetic disk again. That is, it has a function of performing copying.

Further, a magnetic recording / reproducing apparatus according to the present invention comprises:
At least one magnetic recording medium, a magnetic recording medium driving unit for driving the magnetic recording medium, a magnetic head for recording / reproducing information on / from the magnetic recording medium, a magnetic head driving unit for driving the magnetic head, A magnetic recording / reproducing apparatus having a control circuit system for processing a recording signal to the head and a reproduction signal from the magnetic head and for processing a control signal of the magnetic recording medium driving section and the magnetic head driving section; , A copy control circuit, and a reproduction output detection circuit are added, and a predetermined signal is recorded in advance in a part of the magnetic recording / reproducing apparatus, and the reproduction output is periodically measured. If the signal is smaller than a preset reference value, the signal is recorded again, and then the information recorded in the magnetic recording / reproducing apparatus is automatically copied. It is. That is, in the embodiment shown in FIG. 3, the interface unit 4 and the read / write control unit 5 connected to the interface unit 4 respectively.
A magnetic head 8 connected to the read / write control unit 5, a head carriage 9 connected to the head positioning control unit 6, and a spindle motor. A magnetic disk drive having at least a spindle motor 10 connected to a motor controller 7, a cache memory 2, a copy control circuit 3, a timer 13, and a reproduction output detection circuit 17; 3 is a cache memory 2, an interface
It is connected to a face section 4, a read / write control section 5, a head positioning control section 6, a spindle motor control section 7, and a reproduction output detection circuit 17, and the reproduction output detection circuit 17 is Connected to the read / write control unit 5, the head positioning control unit 6, the spindle motor control unit 7, and the clock unit 13, and record a predetermined reference signal in a part of the magnetic disk drive in advance. A signal for activating the reproduction output detection circuit 17 is periodically generated from the timer 13, and the reproduction output of the reference signal is measured. When the reproduction output is smaller than a preset reference value, the reproduction output detection circuit 1 is activated.
7, a signal for activating the copy control circuit 3 is issued, and the reference signal is recorded again, and then information recorded in the magnetic disk device 23 is automatically copied.

Further, a magnetic recording / reproducing apparatus according to the present invention comprises:
If the temperature in any of the above magnetic recording and reproducing devices is higher than a preset reference value,
It has a function of automatically copying information recorded in the magnetic recording / reproducing device to the magnetic recording / reproducing device or another recording device, and is configured by adding a temperature sensor and a time measuring device. When the temperature in the magnetic recording / reproducing device is higher than a preset reference value, the information recorded in the magnetic recording / reproducing device at a shorter time interval than when using at room temperature is read by the magnetic recording / reproducing device or another recording device. It is characterized by having a function of automatically copying to an apparatus.
For example, the embodiment shown in FIG. 4 is obtained by adding this method to the embodiment shown in FIG.
And a read / write control unit 5, a head positioning control unit 6, and a spindle motor control unit 7 connected to the interface unit 4, respectively, and a read / write control unit 5 connected to the read / write control unit 5. In a magnetic disk drive having at least a magnetic head 8, a head carriage 9 connected to a head positioning control unit 6, and a spindle motor 10 connected to a spindle motor control unit 7, a first clock It has a device 1, a cache memory 2, a copy control circuit 3, a temperature sensor 18, and a second timekeeping device 19. The copy control circuit 3 comprises a first timekeeping device 1, a cache memory 2, and an interface unit 4. , A read / write control unit 5, a head positioning control unit 6, a spindle motor control unit 7, a temperature sensor 18, and a second time-measuring device 19, respectively. In addition to information copying, the temperature inside the magnetic disk device is constantly measured by the temperature sensor 18 while the magnetic disk device is running, and when the temperature is higher than a preset reference value, the temperature sensor 18 detects the temperature inside the magnetic disk device. A signal for activating the second timing device 19 is issued, and the second timing device 19 is activated.
From the copy control circuit 3 at a shorter time interval than when using at room temperature.
And a function of automatically copying information recorded in the magnetic disk device to the magnetic disk device or another recording device.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of a magnetic recording / reproducing apparatus to which the present invention is applied will be described in detail with reference to the accompanying drawings.

(Embodiment 1) FIG. 1 is a diagram showing the configuration of a control system of an embodiment of a magnetic disk drive according to the present invention. In the figure, reference numeral 20 denotes a magnetic disk device control circuit system. The magnetic disk device control circuit system 20 includes a clock device 1, a cache memory 2, a copy control circuit 3, an interface unit 4, and a lead. A copy control circuit 3 includes a clock unit 1, a cache memory 2, an interface unit 4, a read / write unit, and a write / write control unit 5, a head positioning control unit 6, and a spindle motor control unit 7. Control unit 5,
The interface unit 4 is connected to a head positioning control unit 6 and a spindle motor control unit 7, and a read / write control unit 5, a head positioning control unit 6, and a spindle motor control unit. The read / write control unit 5 is connected to a magnetic head 8.
In addition, the head positioning control unit 6
The spindle motor control section 7 is connected to the spindle motor 10 respectively.

Normally, the operation for recording / reproducing is the same as in the conventional example. First, the magnetic disk is rotated by the spindle motor 10, the magnetic head 8 is moved to a desired track by the head carriage 9, and then the formation and detection of recording magnetization are performed by the magnetic head 8. These operations are controlled by a spindle motor control unit 7, a head positioning control unit 6, and a read / write control unit 5, respectively.

In addition to performing the above-described normal operation, all the existing files are sequentially reproduced every year after the manufacture of the magnetic disk drive, and the information is temporarily stored in the cache memory 2 and the information is temporarily stored in the cache memory 2. In the same area on the disc. When the magnetic disk drive is manufactured, the timekeeping device 1 is started, and every time one year has passed, a signal for starting the copy control circuit 3 is issued from the timekeeping device 1, and the above operation is automatically performed.

The difference between the present embodiment and the configuration of the conventional example shown in FIG. 3 is that a clocking device 1, a cache memory 2, and a copy control circuit 3 are added to a conventional magnetic disk device control circuit system. A signal for activating the copy control circuit 3 is periodically issued from the timekeeping device 1 to sequentially reproduce information already recorded in the magnetic disk device and temporarily store the information in the cache memory 2, and then, automatically reproduce the information on the magnetic disk again. It has a function of recording, that is, copying. It is to be noted that the existing clocking device 1 and cache memory 2 are sufficient, and the copy control circuit 3 is composed of only a portion required for copy control in an existing disk controller.

Here, an example of a magnetic disk drive equipped with the control circuit system 20 of the present embodiment will be described with reference to FIG. 6A and 6B are schematic configuration diagrams of an embodiment of a magnetic disk drive according to the present invention, in which FIG. 6A is a plan view, and FIG. 6B is a cross-sectional view of a portion indicated by line AA ′ in the plan view. . In FIG. 1, reference numeral 15 indicates a magnetic recording medium.
Magnetic disk of a system-based sputter medium, 10 is a magnetic recording medium 1
A spindle motor 5 for rotating and driving 5; a magnetic head 8 for recording and reproducing signals on a magnetic recording medium; and a so-called rotary 9 for moving the magnetic head 8 in a radial direction on the magnetic recording medium. A head carriage 20 called an actuator is a magnetic disk drive control circuit system. A plurality of magnetic recording media are mounted on the spindle motor 10,
A magnetic head 8 is provided on each of the front and back surfaces of each magnetic recording medium.

In this magnetic disk drive, a PRML system is used for reproducing waveform signal processing, and a servo track positioning system is used for positioning the magnetic head 8.
The magnetic characteristics of the magnetic recording medium 15 using a system-based sputter medium are as follows.
The circumferential coercive force is 3000 Oe and the rotational speed of the spindle motor is 7200 rpm. Magnetic head 8
Used a self-induction type head for recording and a magnetoresistive head for reproduction. The track width and gap length of the recording head are 1.3 microns and 0.3 microns, respectively.
4 microns. The track width and gap length of the read head are 1.1 microns and 0.2 microns, respectively. The areal recording density is 5 gigabits per square inch.

FIG. 7 shows a characteristic diagram a of the result of measuring the dependence of the normalized reproduction output on the elapsed time at room temperature using the magnetic disk device configured as described above. This is because the reproduction output is measured immediately after the signal is recorded on the magnetic disk device of the present embodiment, then the host side is left without doing anything, the reproduction output is measured again at a later date, and the value immediately after recording is obtained. It is compared with. A characteristic diagram b of the conventional magnetic disk drive is also shown. The minimum required reproduction output value for use as a product is indicated by a broken line c.
In the conventional magnetic disk device, the reproduction output decreases with the passage of time, and after one year and a half, the reproduction output falls below the minimum value required for use as a product. On the other hand, the magnetic disk device of this embodiment has a higher value. It turns out that it maintains a high state. Therefore, it can be seen that the magnetic disk drive having the configuration of this embodiment is effective in maintaining high reliability.

In this embodiment, the period for re-recording information is set to 1
Although the year is used, the period may be set to another value according to the specifications of the recording / reproducing system and the magnetic characteristics and thermal stability of the magnetic disk. Further, in the present embodiment, at the time of copying, the information was copied to the same place as the original place where the information was recorded, but the copy was made to another place in the same magnetic disk device or to another recording device. Is also good. Also, during the above-mentioned periodical automatic copying operation, a message to the effect that "Now the periodical automatic copying is in progress" may be sent to the host.

Alternatively, the above automatic copying function may be added to the host computer.

(Embodiment 2) FIG. 2 is a schematic configuration diagram of an embodiment of a control system of a magnetic disk drive according to the present invention. In the figure, reference numeral 22 denotes a magnetic disk drive control circuit system. For the sake of convenience, the same components as those of the first embodiment shown in FIG. Omitted. That is, in the magnetic disk device control circuit system of the present embodiment, in addition to adding the cache memory 2 and the copy control circuit 3 to the conventional magnetic disk device control circuit system, the search control circuit 12 and the first timekeeping device 1
3 and a second timing device 14. The copy control circuit 3 includes a cache memory 2, an interface unit 4, a read / write
It is connected to a write control unit 5, a head positioning control unit 6, a spindle motor control unit 7, and a search control circuit 12, and the search control circuit 12 further includes an interface.
Source unit 4, read / write control unit 5, head positioning control unit 6, spindle motor control unit 7, first timing device 1.
3 and a second time measuring device 14, respectively. The first time measuring device 13 issues a signal for activating the search control circuit 12 every 30 days, and outputs the current year output from the second time measuring device 14. By referring to the date, of the information already recorded in the magnetic disk device,
Information that is older than one year is retrieved, the information name is transferred to the copy control circuit 3, the corresponding information is sequentially reproduced, temporarily stored in the cache memory 2, and the information is recorded again in the same area on the disk. The point that the operation is performed automatically is different from the configuration of the first embodiment. It should be noted that the existing cache memory 2, the first timer 13, and the second timer 14 are sufficient, and the copy control circuit 3 and the search control circuit 1 are sufficient.
Reference numeral 2 denotes only a part required for controlling each function in the existing disk controller.

The control circuit system 22 of this embodiment is similar to that of FIG.
When used as a substitute for the control circuit system 20 in the magnetic disk device shown in FIG. 7, the measurement result of the elapsed time dependence of the normalized reproduction output at room temperature was the same as that of Example 1 shown in FIG. Accordingly, it can be seen that even the magnetic disk device having the configuration of the present embodiment is effective in maintaining high reliability.

In the present embodiment, the cycle for checking the last recording date of the existing file and the elapsed time when it is determined that the information needs to be recorded again are set to 30 days and 1 year, respectively. These periods may be set to other values depending on the magnetic properties and thermal stability of the disk.
Further, in the present embodiment, at the time of copying, the information was copied to the same place as the original place where the information was recorded, but the copy was made to another place in the same magnetic disk device or to another recording device. Is also good. Also, during the above-mentioned periodical automatic copying operation, a message to the effect that "Now the periodical automatic copying is in progress" may be sent to the host.

Alternatively, the above-described automatic copying function may be added to the host computer.

(Embodiment 3) FIG. 3 is a schematic configuration diagram of an embodiment of a control system of a magnetic disk drive according to the present invention. In the figure, reference numeral 23 denotes a magnetic disk drive control circuit system. For the sake of convenience, the same components as those of the first embodiment shown in FIG. Omitted. That is, in the magnetic disk device control circuit system of the present embodiment, in addition to adding the cache memory 2 and the copy control circuit 3 to the conventional magnetic disk device control circuit system, the clock device 13 and the reproduction output detection circuit 1
The copy control circuit 3 includes a cache memory 2, an interface unit 4, a read / write control unit 5, a head positioning control unit 6, a spindle motor control unit 7, and a reproduction output detection circuit. The read output detection circuit 17 is connected to the read / write control unit 5, the head positioning control unit 6, the spindle motor control unit 7, and the timer 13, respectively. A fixed reference signal is recorded in advance in a part of the disk device, and a signal for activating the reproduction output detection circuit 17 from the timer 13 is set to 3
The first embodiment is characterized in that the reproduction output of the reference signal is emitted every 0 days and a signal for starting the copy control circuit 3 is issued from the reproduction output detection circuit 17 when the reproduction output is smaller than a preset reference value. Configuration. In this embodiment,
A value corresponding to 0.85 times the normalized reproduction output is set as a reference value. After the copy control circuit 3 is started, the reference signal is recorded again, and the information recorded in the magnetic disk device is sequentially reproduced and temporarily stored in the cache memory 2 to store the information on the disk. Re-record in the area. It is to be noted that the existing cache memory 2 and clocking device 13 are sufficient, and that the copy control circuit 3 and the reproduction output detection circuit 17 have various functions in the existing disk controller or read / write control unit. It is composed of only the parts required for the control of.

The control circuit system 23 of this embodiment is the same as that shown in FIG.
When used as a substitute for the control circuit system 20 in the magnetic disk device shown in FIG. 7, the measurement result of the elapsed time dependence of the normalized reproduction output at room temperature was the same as that of Example 1 shown in FIG. Accordingly, it can be seen that even the magnetic disk device having the configuration of the present embodiment is effective in maintaining high reliability.

In this embodiment, the period for checking the reproduction output of the reference signal and the reference value of the reproduction output are set to 30 days and a value corresponding to 0.85 times the standardized reproduction output, respectively. Other values may be set according to the magnetic characteristics and the thermal stability of the magnetic disk. Further, every time the magnetic disk drive is started, a work of checking the reproduction output of the reference signal may be performed. Further, in the present embodiment, at the time of copying, the information was copied to the same place as the original place where the information was recorded, but the copy was made to another place in the same magnetic disk device or to another recording device. Is also good. Also, during the above-mentioned periodical automatic copying operation, a message to the effect that "Now the periodical automatic copying is in progress" may be sent to the host.

Alternatively, the above-described automatic copying function may be added to the host computer.

(Embodiment 4) FIG. 4 is a schematic configuration diagram of an embodiment of a control system of a magnetic disk drive according to the present invention. In the figure, reference numeral 24 denotes a magnetic disk drive control circuit system. For the sake of convenience, the same components as those in the first embodiment shown in FIG. Omitted. That is, in the magnetic disk drive control circuit system of the present embodiment, in addition to the addition of the first clock device 1, the cache memory 2, and the copy control circuit 3 to the conventional magnetic disk drive control circuit system, 18
And a second timer 19, and the copy control circuit 3
, A cache memory 2, an interface unit 4, a read / write control unit 5, a head positioning control unit 6, a spindle motor control unit 7, and a second timing device 1.
9 and a temperature sensor 18 is connected to a second time measuring device 19. In addition to periodically and automatically copying information as shown in the first embodiment, the temperature sensor 18 is also connected to a magnetic sensor. During the start of the disk drive, the temperature inside the magnetic disk drive is constantly measured by the temperature sensor 18 and the temperature is 60 ° C.
If it is higher, the temperature sensor 18 issues a signal for activating the second timer 19, and the second timer 19 issues a signal for activating the copy control circuit 3 every six months after the activation. This embodiment differs from the first embodiment in that information recorded in the disk device is automatically copied to the magnetic disk device or another recording device. After the copy control circuit 3 is started, the information recorded in the magnetic disk device is sequentially reproduced, temporarily stored in the cache memory 2, and the information is recorded again. It should be noted that the first timer 1, the cache memory 2, the temperature sensor 18 and the second timer 19 to be added are sufficient as existing ones, and the copy control circuit 3 has a copy function in the existing disk controller. It is composed of only the parts required for the control of.

The control circuit system 24 of the present embodiment is the same as that shown in FIG.
When used as a substitute for the control circuit system 20 in the magnetic disk device shown in FIG. 7, the measurement result of the elapsed time dependence of the normalized reproduction output at room temperature was the same as that of Example 1 shown in FIG. Separately, the same measurement was performed in an atmosphere at a temperature of 60 ° C. FIG. 8 shows a characteristic diagram d of the measurement result. A characteristic diagram e of the conventional magnetic disk drive is also shown. The minimum required reproduction output value for use as a product is indicated by a broken line c. In the conventional magnetic disk drive, the reproduction output decreases with the passage of time, and after one year, it falls below the minimum required for use as a product. On the other hand, the magnetic disk drive of this embodiment has a higher output. It can be seen that the state is maintained.

Therefore, it can be seen that the magnetic disk drive having the configuration of this embodiment is effective in maintaining high reliability even at a high temperature of about 60 ° C.

In the present embodiment, the temperature at which the temperature sensor 18 issues a signal for activating the second timer 19 is set to 60 ° C.
Although the period at which the second timer 19 issues the signal for activating the copy control circuit 3 is set to six months, the period may be changed to another period according to the specifications of the recording / reproducing system and the magnetic characteristics and thermal stability of the magnetic disk. May be set to a value. Further, in this embodiment, the temperature sensor 18 and the second timer 19 are added to the first embodiment, but may be added to the second or third embodiment. Further, in the present embodiment, at the time of copying, the information was copied to the same place as the original place where the information was recorded, but the copy was made to another place in the same magnetic disk device or to another recording device. Is also good. Also, during the above-mentioned periodical automatic copying operation, a message to the effect that "Now the periodical automatic copying is in progress" may be sent to the host.

Alternatively, the above-described automatic copying function may be added to the host computer.

[0036]

According to the present invention, since the recording magnetization formed on the magnetic recording medium is re-recorded before decreasing to a value which is difficult to reproduce without error, high-density recording is performed. The information can be held semi-permanently in a reproducible state, and the reliability as a magnetic recording / reproducing device can be maintained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of a magnetic recording / reproducing device control circuit system according to the present invention.

FIG. 2 is a configuration diagram showing another embodiment of the magnetic recording / reproducing device control circuit system according to the present invention.

FIG. 3 is a configuration diagram showing still another embodiment of a magnetic recording / reproducing device control circuit system according to the present invention.

FIG. 4 is a configuration diagram showing still another embodiment of a magnetic recording / reproducing device control circuit system according to the present invention.

FIG. 5 is a configuration diagram showing an example of a conventional magnetic recording / reproducing device control circuit system.

FIGS. 6A and 6B are schematic configuration diagrams showing one embodiment of a magnetic disk drive provided with a magnetic recording / reproducing device control circuit system according to the present invention, wherein FIG. 6A is a plan view, and FIG. It is sectional drawing of the part shown by A 'line.

FIG. 7 is a characteristic diagram showing the elapsed time dependency of the normalized reproduction output at room temperature of the magnetic disk device having the magnetic recording / reproducing device control circuit system according to the present invention shown in FIG. The characteristic line a is the result when the magnetic disk device control system according to the embodiment of the present invention is implemented, the characteristic line b is the result when the conventional example is implemented, and the broken line c is the minimum required for use as the device. It shows the reproduction output value.

FIG. 8 is a graph showing the elapsed time dependence of normalized reproduction output in a 60 ° C. atmosphere of a magnetic disk device having the magnetic recording / reproducing device control circuit system according to the present invention shown in FIG. A characteristic line d is a result when the magnetic disk device control system according to the embodiment of the present invention is implemented, a characteristic line e is a result when the conventional example is implemented, and a broken line c is a minimum value for use as the device. It shows a required reproduction output value.

[Explanation of symbols]

1, 13, 14, 19: clock device, 2: cache memory, 3: copy control circuit, 4: interface unit, 5:
Read / write controller, 6 ... Head positioning controller, 7
... Spindle motor control unit, 8 ... magnetic head, 9 ... head carriage, 10 ... spindle motor, 11 ... magnetic disk device interface unit, 12 ... search control circuit,
Reference numeral 15: magnetic recording medium, 16: signal processing unit, 17: reproduction output detection circuit, 18: temperature sensor, 20, 22, 23, 2
4, 25: magnetic disk drive control circuit system; 21: part of host computer control system.

Claims (7)

[Claims] At least one magnetic recording medium, a magnetic recording medium drive unit for driving the magnetic recording medium, a magnetic head for recording / reproducing information on / from the magnetic recording medium, and a magnetic head for driving the magnetic head A magnetic recording / reproducing apparatus comprising: a driving unit; and a control circuit system for processing a recording signal to the magnetic head and a reproduction signal from the magnetic head and for processing a control signal of the magnetic recording medium driving unit and the magnetic head driving unit. A magnetic recording / reproducing apparatus comprising means for periodically copying information recorded in the magnetic recording / reproducing apparatus. 2. A magnetic recording medium, a magnetic recording medium driving section for driving the magnetic recording medium, a magnetic head for recording / reproducing information on / from the magnetic recording medium, and a magnetic head for driving the magnetic head A magnetic recording / reproducing apparatus comprising: a driving unit; and a control circuit system for processing a recording signal to the magnetic head and a reproduction signal from the magnetic head and for processing a control signal of the magnetic recording medium driving unit and the magnetic head driving unit. A magnetic recording / reproducing apparatus comprising means for copying information after a predetermined time has elapsed after recording the information. 3. The magnetic recording / reproducing apparatus according to claim 1, further comprising a clock device, a cache memory, a copy control circuit, and a search control circuit. 4. A magnetic recording medium, at least one magnetic recording medium, a magnetic recording medium driving unit for driving the magnetic recording medium, a magnetic head for recording / reproducing information on / from the magnetic recording medium, and a magnetic head for driving the magnetic head A driving unit, a control circuit system for processing a recording signal to the magnetic head and a reproduction signal from the magnetic head, and processing a control signal for the magnetic recording medium driving unit and the magnetic head driving unit, a timing device, and a copy control circuit Wherein the timing device periodically issues a signal for activating the copy control circuit. 5. The magnetic recording / reproducing apparatus according to claim 4, wherein, after a signal for activating said copy control circuit is issued from said timing device, information recorded on said magnetic recording medium is sequentially reproduced. A magnetic recording / reproducing apparatus, wherein after temporarily storing the information in an external storage means, the information is re-recorded in the original place where the information was recorded. 6. The magnetic recording / reproducing apparatus according to claim 1, wherein when the temperature in the magnetic recording / reproducing apparatus is higher than a preset reference value, the data is recorded in the magnetic recording / reproducing apparatus. A magnetic recording / reproducing apparatus having means for copying the information stored therein to the magnetic recording / reproducing apparatus or another recording apparatus. 7. The magnetic recording / reproducing apparatus according to claim 6, further comprising a clock device, a temperature sensor, a cache memory, and a copy control circuit.