JPH01184661A - Magnetic disk driving device - Google Patents

Abstract

PURPOSE:To prevent the destruction of recording information by the attraction phenomenon of a magnetic head and a disk by rotating a disk motor intermittently on a recording and reproducing stopping and positioning the magnetic head in the most internal circumference neighborhood to have no information recording. CONSTITUTION:On the stopping of a recording and reproducing action, a disk motor 1 is rotatingly driven intermittently, and a recording medium 2 is rotated intermittently. Besides, on a stand-by condition in which the writing and the reading of data are not executed, a magnetic head 4 is moved to the most internal circumference track neighborhood in which information is recorded with the recording medium 2 little, and the disk motor 1 is rotatingly driven intermittently every a prescribed time. By constituting like this, the same part of the magnetic head 4 and the recording medium 2 is prevented to continue to be brought into contact for a long time. Besides, even when an attraction phenomenon is generated to the magnetic head 4 and the recording medium 2 with stopping at the most internal circumference position, an information destruction can be minimized.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) This invention aims to prevent damage to magnetic disks such as floppy disks due to the attraction phenomenon of the magnetic head when recording and reproduction are stopped. The present invention relates to a magnetic disk drive device.

(Prior Art) In recent years, 70 disk drives (hereinafter referred to as FDDs) have come into wide use in backup memory devices of telephone exchanges, word processors, and the like.

Conventionally, in the initial state of this FDD, the magnetic head stops at the outermost circumference of the floppy disk (hereinafter referred to as the disk), and when the recording or playback operation stops, it stops at that position (on the track of the disk). For this reason, if left unattended for a period of time, especially in high temperature and high humidity conditions, an adhesion phenomenon occurs in which the magnetic head and disk stick together, resulting in the destruction of the information recorded on the disk.
There was a problem in that the rotary drive device that rotates the disk stopped working.

Also, for example, an FD using a disk with a diameter of 3.5 inches
In D, loading and unloading (approaching and separating) the magnetic head to and from the disk in order to downsize the FDD.
Many 3.5-inch FDDs do not have a head loading mechanism, so when a recording or playback operation is completed, the magnetic head remains stopped at the track position at that time and remains in contact with the disk. Therefore, the probability f[ of the adsorption occurring is further increased by 1°.

In particular, the above-mentioned F
P B X (privatebr
(anch exchange) or key telephone equipment, Ft)D may be used to exchange programs or customer data (
The FDD is used to store information such as speed dial numbers and ID codes that users have registered, so the FDD is driven only when it is necessary to replace customer data, and the disk is loaded into the FDD. It is common for the disc to be left in the loading state for a long time, which further increases the risk that the disc will develop a valley.

Although the mechanism of the adsorption phenomenon is not clear, when the temperature and humidity become high, the fluidity of the surfactant applied to the disk surface increases, and this surfactant becomes a hair III'r.
It is said that this phenomenon occurs when the magnetic head flows into the contact area between the magnetic head and the disk and becomes stuck.

If this adsorption force exceeds the starting torque of the disk rotation motor, the disk rotation motor may not be able to drive, or excessive force may be applied to the disk surface on which data is recorded, causing data to be destroyed. This is what happens.

(Problems to be Solved by the Invention) The present invention provides a magnetic disk drive that reliably prevents destruction of data recorded on the disk and malfunction of the disk motor by preventing the disk from adhering to the magnetic head. The purpose is to capture and provide equipment.

[1 Configuration 1 (Means and effects for solving the problem) This invention includes a disk-shaped recording medium for storing data, a magnetic head for writing and reading data on the recording medium,
a first drive means for rotationally driving the recording medium; a second drive means for moving and driving the magnetic head in the radial direction of the medium; and a standby state in which the data is not being recorded or read. At this time, the second drive means stops driving, and the first drive means is provided with a control means for intermittently rotationally driving the first drive means at predetermined time intervals.

According to such a configuration, the device stops recording and reproducing operations.
Then, the control means intermittently rotates the first drive means to intermittently rotate the recording medium.

Therefore, it is possible to prevent the magnetic head from continuing to contact the same portion of the recording medium for a long time.

Moreover, in this invention, instead of the control means having the above configuration,
When the magnetic head is in a standby state where data is not being written or read, the second driving means is controlled to move the magnetic head to a predetermined track near the innermost track of the recording medium, and after this movement, the second driving means is driven. Another control tllf stage for intermittently driving the first drive means to rotate at predetermined intervals is provided.

According to this configuration, by driving the second driving means in the standby state, the magnetic head is moved to a predetermined track near the innermost track of the recording medium, and after this movement, the driving means of the cylinder 1 is driven. The recording medium is intermittently rotated by being intermittently rotationally driven. There is little information recorded on the tracks near the innermost circumference, and since the recording medium was made to rotate intermittently on the tracks near the innermost circumference, it did not stop at this innermost circumference position for a long time. Even if an attraction phenomenon occurs between the magnetic head and the disk, the destruction of information can be minimized. In particular, destruction of important data such as the format recorded on the outer periphery can be completely prevented.

(Example) FIG. 2 shows the internal structure of the FDC 7 using a 3.5-inch disk, and FIG. 3 is a sectional view thereof.

2 and 3, the magnetic head 4 is attached to a carriage 3, and the carriage 3 is moved in the disk radial direction by a step motor 5 via a worm gear (not shown). A radial movement is performed. A disk motor 1 is provided at the center of the disk 2, and the disk 2 is rotationally driven by the disk motor 1. Each of these components is housed in the main body case 6 of the DD.

As described above, this 3-inch F''DD is not provided with a head loading mechanism for bringing the magnetic head 4 into and out of contact with the disk 2.

FIG. 1 shows the first embodiment of this invention.
) 7 and a central control unit (CCU>10) that exchanges signals with the FDC 7, and the FDC 7 is the central control unit that exchanges signals with the disk motor 1,
In addition to the step motor 5 and the magnetic head 4, these elements are controlled l'? It has a control device 20. 1lilJ
The IIl device 20 includes a rotation control section 21 that controls the rotation and stop of the disk motor 1, a rotation speed detection section 22 that detects the rotation speed of the disk rotor 1, and a forward/reverse control section 23 that controls the step motor 5 in forward and reverse directions. , and a rotation control section 24 that controls rotation and stop of the step motor 5. Note that the track indicates the position in the radial direction of the disk 2, and the outermost track is 00 track and the innermost track is 7.
There will be 6 tracks (see Figure 3).

On the other hand, the CCU10 is a floppy drive controller (FD) that sends and receives signals to and from the control device 20 of the FDC7.
C) 11. Data separator 12 for separating and modulating data signals and clock pulses, read/write (R/W)
>It has a direct memory access (DMA) 13 for transferring data to the RAM 14, a RAM 1/I, a CPU 15, a timer 30, etc.

The timer 30 measures a preset time (for example, one hour), and inputs the mJ-inclusive signal IR to the CPL 115 every time the set time elapses.

) - Although there are many types of signals exchanged between the DCII and the control device 20, only those related to the present invention will be exemplified below.

・"MOTORON" (abbreviated as MO) is a signal to rotate/stop the disk motor 1. "1" means rotation, "
0" to stop.

・"DIRECTION 5ELECT" (abbreviated as O8) This is a signal for rotating the step motor 5 forward/reversely, and the direction of movement of the magnetic head 4 in the disk radius rectangle can be determined by this signal.

"1" is the centripetal direction, and [0] is the centrifugal direction.

・"51EP" (abbreviated as SP) Movement of the magnetic head 4 in the disk radial direction l1lrl! This is a signal that determines the position of the track, and one pulse moves the track one track.

When moving three tracks, three pulses are output.

・"WRITE GATE" (abbreviated as WG) When this signal is "1", the internal circuit (not shown) in the control device ff20 is put into an operable state. Note that when this signal is "0", the drive is prohibited from entering.

・“READY” (abbreviated as RY) This is a signal input from the rotation speed detection unit 22 to the FDCl 1. When this signal is “1”, the disk 2 is inserted and the rotation speed of the disk motor 1 is constant. indicates that it has become.

The operation of the configuration shown in FIG. 1 will be explained with reference to flowchart II shown in FIG. This flowchart is
This is an addition of an adsorption prevention routine (steps 200 to 230) to the normal read/write operations (steps 100 to 180).

When performing read/write operations, ccui.

FDCl 1 first outputs a "M O" signal (step 100). After confirming that the disk 2 is loaded, the control device 20 of the FDD 7 causes the rotation control unit 21 to rotationally drive the disk motor 1 (step 120).
). The rotation speed detection unit 22 detects the rotation speed of the disk motor 1, and when this rotation speed reaches a predetermined rotation speed,
Output RY $1 signal (steps 130, 140>
.

Upon receiving this 'RY' signal, the FDCl 1 outputs a 'DS' signal and an 'SP' signal in order to move the magnetic head 4 to a desired track.In the case of a read operation,
The CPU 15 writes the read data input to the data separator 12 into the RAM 14 via the DMA 13. In addition, in the case of a write operation, the data stored in the RAM 14 is
MA13, magnetic head 4 via data separator 12
and written to disk 2 (step 160). Thereafter, the CPU 15 performs data denicking to confirm that there is no abnormality (step 170).

At this point, the magnetic head 4 is at the track position where the access (read/write) is performed and is in contact with the disk 2. In the conventional read/write operation, the CPU 15 then reads 11 M O#l
After setting the signal to "0" and stopping the disc motor 1,
The magnetic head 4 entered the standby state with the magnetic head 4 in contact with the track position at the time of access, but in this embodiment, the CP
After confirming the completion of access (read/write operation) to the FDD (step 180), U15 executes the following adsorption prevention routine.

When the timer 30 measures a predetermined time 1J (step 200), it inputs an interrupt signal IR to the CPU 15 (step 210).

The CPU 15 controls the FDD under the control of the interrupt control unit.
The pJ interrupt signal IR from the timer 30 is accepted only when no access (read/write operation) is being made to the timer 30, and when the interrupt signal IR is detected (step 220), the FDCl 1 outputs "'". M
O” signal is set to “1” for a short predetermined period of time. As a result, the rotation control unit 21 controls the disk motor 1 as 'M O'.
The disk 2 rotates for a period of time when the signal is "1", and after rotating for a predetermined period of time, the disk 2 is stopped (step 230). C.P.
By repeatedly executing such control every time an interrupt signal from the timer 30 is input, U15 controls the disk 2 intermittently as shown in FIG. rotate. That is, in a system that does not have a head loading device, when access to the FDD ends and enters a standby state, the magnetic head 4 is in contact with the disk 2 at the track position where the access ended. After the standby state, the disk motor 1 is rotated intermittently to cause the magnetic head 4 to run on the track.

According to this embodiment, since the disk 2 is intermittently driven to rotate in the initial state and in the standby state after recording and reproduction are completed, the magnetic head 4 does not continue to contact the same portion of the disk 2 for a long time. It is possible to prevent the phenomenon of adsorption of the magnetic head 4 to the disk 2 and prevent the destruction of information recorded on the disk 2.

Note that the time set in the timer 30 is not particularly limited, and can be appropriately selected depending on the conditions of the disc 2 and its surroundings.

Next, a second embodiment of the present invention will be described with reference to FIGS. 6 and 7.

The configuration shown in FIG. 6 has a head position detection section 25 added to the control device 20 of the FDD 7 having the configuration shown in FIG. The head position detecting section 25 detects position 1 of the magnetic head 4 in the disk radial direction, that is, the track position, and outputs a signal "TRACK" indicating the detected track number tfi.
No” (TN, !: approximate size) is output.

The operation of this second embodiment will be explained below with reference to the flowchart of FIG. In the flowchart of FIG. 7, a suction prevention routine A is added before the suction prevention routine B corresponding to the first embodiment.

That is, when the CPU 15 confirms that the access (read/write operation) to the FDD is completed, it first determines the current track position of the magnetic head 4 based on the output TN of the head position detection section 25. Then, based on this determination position, the number of pulses of the 'sp' signal required to move the magnetic head 4 to the innermost track (track 76, see Figure 3) is incremented by one. ``The number of signal pulses corresponds to the number of moving tracks.

Then, the CPU 15 uses it D by FDCl 1.
A signal "1" of S + is sent to the forward/reverse control section 23, and a "SP" signal consisting of the calculated number of pulses is sent to the rotation control section 24 (step 400). As a result, the forward/reverse control is performed. The section 23 and the rotation control section 24 drive the step motor 5' to move the magnetic head in the centripetal direction and position it on the innermost track (76 tracks). Confirm that the magnetic head 4 is located on the innermost track!
step 410). After this 'Ili recognition FDC1
1, the 'MO' signal is set to '0' to stop the disk motor 1 (step 420), and then the procedure shifts to the adsorption prevention routine B.

The operation of this routine B is similar to that of the first embodiment, and the CPL 115 intermittently controls the disk 2 with the magnetic head 4 positioned at the innermost track of the disk 2 based on the interrupt signal 11< from the timer 30. (steps 430-460).

According to this embodiment, when the FDD is in a standby state where information is not being recorded or reproduced on the disk 2, the magnetic head 4 is located at the innermost circumference of the disk 2 where a small proportion of information is recorded. Even if the magnetic head 4 and the disk 2 should stop at this position for a long period of time and the magnetic head 4 and the disk 2 should collide, the destruction of information can be kept to a minimum. In particular, destruction of important data such as the format recorded on the outer periphery can be completely prevented.

Furthermore, even if an adsorption phenomenon occurs between the magnetic head 4 and the disk 2, and the magnetic head 4 and the disk 2 stick together, the sticking position is the closest point to the rotation axis of the disk motor 1, so Recovery from adsorption can be expected with a small torque.

If the moment of inertia at one point on the disk 2 is J, then from the above equation it can be seen that a torque proportional to the square of the radius is required to recover from adsorption, and that the further away from the rotation axis the disadvantageous it becomes. .

In the above embodiment, the magnetic head is evacuated to the innermost track, but the present invention is not limited to this, and the magnetic head may be evacuated from any track near the innermost track.

FIG. 8 shows this l'l light applied to a digital telephone exchange, in which the FDD 7 is used as a backup memory in the event of a power outage.

This digital telephone exchange equipment is located at Ext. Highway 11-1.
a time switch 40 that performs exchange connection between the internal highway IH, the external highway OH, and the internal highway 1 to 1; and a central office line unit 4 that is an interface for external lines.
1, and a telephone unit 42 which is an extension interface.
and a terminal 43, for example a telephone, and a data highway DH, as well as the aforementioned central fl+IJ III unit (CCU>10 and FDD7).

In this device, the disk F[)D7 contains exchange programs and customer data (yrj compressed numbers, etc.)
Transferred to AM. Therefore, in this, FD
D is P? Unless it is necessary to re-transfer the recorded data due to electricity, etc., or when it is necessary to re-capture customer data due to Yuna, it is in a standby state, and the above-mentioned adsorption phenomenon occurs. Very likely.

Therefore, this intersection! j! In the device, FDD7 and CCU
Destruction of recorded data is prevented by providing the structure and function for preventing adsorption as described in the first or second embodiment above.

Note that the present invention is not limited to the above-mentioned digital telephone exchange device, but can also be applied to any other electronic equipment such as a word processor, PBX, etc.
It can be applied to

[Effects of the Invention] As described above, according to the present invention, since the disk motor is intermittently rotated when recording and reproduction of an FDD is stopped, the magnetic head does not come into contact with the same part of the disk for a long time, and the magnetic head Destruction of recorded information due to attraction between the head and the disk can be prevented.

In addition, in this invention, during special recording, the magnetic head is located near the innermost track where there is little possibility that information is recorded, and the magnetic head intermittently runs on this innermost track. , the possibility of occurrence of the adhesion phenomenon is extremely reduced, and even if the adhesion phenomenon should occur, the detachment operation can be performed with a small torque, and the destruction of information can be minimized.

Particularly in equipment such as telephone exchange equipment, which is operated for long periods of time with the disk attached to the FDD, there is a high risk of the absorption phenomenon occurring, and the effects of the present invention are significant.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a first embodiment of the present invention, Fig. 2 is a perspective view showing an example of the internal appearance configuration of an FDD, Fig. 3 is a sectional view thereof, and Fig. 4 is a block diagram of the first embodiment. FIG. 5 is a time chart showing the mode of disk rotation during standby according to the second embodiment, FIG. 6 is a block diagram showing the second embodiment of the present invention, and FIG. An example of its operation is shown in FIG. FIG. 2 is a block diagram showing a configuration example when applied to an apparatus. 1... Disc motor, 2... Disc, 3...
Carriage 7, 4...Magnetic head, 5...Step motor, 7...FDD, 10...CCLI, 15...
...CPLI, 30...Timer.

Claims (2)

[Claims] (1) A disk-shaped recording medium for storing data, a magnetic head for writing and reading data on and from the recording medium, a first driving means for rotationally driving the recording medium, and a first driving means for driving the magnetic head to rotate the recording medium. a second drive moving in the radial direction;
In the magnetic disk drive apparatus, when in a standby state in which data is not being written or read, the second driving means stops driving and the first driving means is activated at predetermined time intervals. A magnetic disk drive device characterized by comprising a control means for intermittently driving rotation. (2) a disk-shaped recording medium for storing data; a magnetic head for writing and reading data on and from the recording medium; a first driving means for rotationally driving the recording medium; a second drive moving in the radial direction;
In the magnetic disk drive device, the magnetic disk drive device is configured to move the magnetic head to a predetermined track near the innermost track of the recording medium when in a standby state in which data is not being written or read. 1. A magnetic disk drive apparatus comprising: a control means for driving and controlling said first driving means, and intermittently rotationally driving said first driving means at predetermined time intervals after said first driving means has been moved.