JPH08306122A - Magnetic disk device - Google Patents

Abstract

PURPOSE: To discriminate which of write-in, read-out or dust is the cause of data destruction, and hence to ensure high reliability. CONSTITUTION: At the time of supplying a power source, a quantity of dust in a part of a dust hole 4 in a disk enclosure(DE) 1 is detected by a photoelectric transducer 5, and when the quantity of dust is large, a spindle motor 3 is not started up by a CPU 8, and this effect is written in a register 9 to make an error report. When the quantity of dust is small, the spindle motor 3 is rotated, and the dust in the DE 1 at that time is detected by a photoelectric transducer 6, and this quantity of dust is counted by a counter 7 to be reported to the CPU 8. When the quantity of dust counted at intervals of a fixed time is larger than a reference value, this effect is written in the register 9 and the spindle motor is stopped by the CPU 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device, and in particular, a disk board and a magnetic head are housed in a disk enclosure (hereinafter referred to as DE) in a hermetically sealed structure, and a magnetic head is levitated by the circulation of internal gas. The present invention relates to a magnetic disk device having a structure for performing the above.

[0002]

2. Description of the Related Art In a conventional magnetic disk device, a data abnormality is usually discriminated by a data writing / reading operation from a host device. for that reason,
When a data abnormality is detected, it is impossible to identify whether it is a write abnormality or dust-induced data corruption.

In order to prevent the data destruction due to this dust, Japanese Patent Laid-Open No. 214063/1990 and Japanese Utility Model Laid-Open No. 2-469.
No. 56, etc. detects the amount of dust in the DE, and when the amount of dust exceeds a reference value, the rotation of the spindle motor is stopped to stop the rotation of the magnetic disk, thereby preventing head crash or the like. Then, a technique for preventing the data destruction is proposed.

[0004]

In the above-described technique, the amount of dust in the DE during system operation is measured after the magnetic disk device is powered on, and the result of this measurement determines that the amount of dust is large. This is a method to control the rotation of the spindle motor when the power is turned on.If a lot of dust is already present immediately after the power is turned on, drive the spindle motor in that state to start the operation to avoid head crash. Not being done, data destruction will occur.

An object of the present invention is to provide a magnetic disk device capable of completely preventing data destruction by detecting the amount of dust in the DE not only during system operation but also at the initial stage of power-on. is there.

[0006]

A magnetic disk device according to the present invention is a disk enclosure, a first dust detecting means for detecting the amount of dust at a predetermined location in the disk enclosure, and the disk encoder when the spindle motor is rotating. Second dust detecting means for detecting the amount of dust in the rotor; first control means for performing rotation start control of the spindle motor according to the detection output of the first dust detecting means when the power is turned on; Second control means for controlling the rotation stop of the spindle motor according to the detection output of the second dust detection means when the spindle motor rotates.

[0007]

The amount of dust in the dust detecting recess provided in the DE is detected immediately after the power is turned on. If the amount of dust is large, the spindle motor is not rotated, and if it is small, the spindle motor is rotated. Then, even during operation, the amount of floating dust in the DE is detected, and if it is above a predetermined value, the power is turned off and the spindle motor is stopped.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of an embodiment of the present invention. In FIG. 1, a magnetic disk 2 and a spindle motor 3 are provided in DE1, and two photoelectric conversion elements 5 and 6 are provided to detect dust in DE1.

The photoelectric conversion element 5 is for detecting the amount of dust in a concave dust hole 4 provided in advance at a predetermined position in the DE 1, and is composed of a light emitting element and a light receiving element. The amount of dust can be measured by illuminating the concave dust hole 4 with a light emitting element and measuring the reflected light with a light receiving element. That is, as shown in FIG. 3, if dust exists in the dust hole 4, the irradiation light is diffusely reflected according to the amount of dust and the amount of light received by the light receiving element decreases in proportion to the amount of dust. The amount of dust can be detected by the photoelectric conversion output of the amount of received light.

Incidentally, FIG. 3A shows a state with dust, and FIG. 3B shows a state without dust.

The photoelectric conversion element 6 detects the amount of dust in the DE 1 when the magnetic disk 2 is rotated by the spindle motor 3, and is composed of a pair of photoelectric conversion elements facing each other. When the magnetic disk 2 rotates, the internal gas circulates, so that a magnetic head (not shown) floats and data can be written and read.

At this time, if dust exists in the DE 1, the dust is also circulated together with the internal gas, and the photoelectric conversion element 6
Since the number of dusts passing through the facing gap (gap between the light emitting element and the light receiving element) also changes accordingly, a pulse corresponding to the number of passing dusts is generated at the output of this photoelectric conversion element. It

Therefore, the output pulse is counted by the counter 7 and the CPU (center processing unit) 8 is counted.
Let me report this. CPU8 is this counter 7
The processing operation as shown in FIG. 2 is performed on the basis of the count content of the above and the detection output of the photoelectric conversion element 5 described above.
Reference numeral 9 indicates a register, the contents of which are set by the CPU 8 and the set contents of the register 9 can be derived to the outside. Further, 10 is a timer.

The operation of the CPU 8 will be described in detail with reference to FIG. First, after turning on the power (step S1), DE
The amount of dust in the dust hole 4 in 1 is detected by the photoelectric conversion element 5. When there is no dust, the reflected light becomes clear as shown in FIG. 3B, and the detection output shows that there is no dust. Therefore, in step S2,
The reference value and the detected output are compared, and if OK (good), the rotation of the spindle motor 3 is started (step S).
3).

After starting the spindle motor, the timer 10 is started (step S4), and the counter 7 for counting the output of the photoelectric conversion element 6 is monitored (step S5). When a certain time has passed by the timer 10 (step S6),
The count content of the counter 7 is checked (step S
7), normality / abnormality is judged by comparing with the specified value.

If it is normal, information indicating that it is normal is written in the register 9, and if necessary, the counting result at that time is also written (step S8). Then, it is determined whether or not the power is off (step S9). If not, the timer 10 is reset and the above operation is repeated again.

If there is an abnormality in step S2, the spindle motor 3 is not started, information indicating the abnormality is written in the register 9 (step S11), and an abnormality report (error report) is made to the host device (error report). Step S1
2). Naturally, the spindle motor 3 is stopped (step S13).

If it is abnormal in step S7, the above-mentioned steps S11 to S13 are similarly executed to perform abnormality processing, and the spindle motor is stopped. If the power supply is cut off in step S9, the spindle motor is stopped (step S10).

[0020]

According to the present invention, by incorporating the dust measurement, which is conventionally performed only in a clean room, both at the time of starting and during the operation of the magnetic disk device, data destruction such as head crash caused by dust is prevented. The effect is that it can be effectively prevented.

Further, when a data error occurs, it is possible to discriminate whether the data writing / reading is defective or the dust is defective, and a highly reliable magnetic disk device can be realized.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an exemplary embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the embodiment of the present invention.

3A is a diagram showing a state with dust in a dust hole, and FIG. 3B is a diagram showing a state without dust.

[Explanation of symbols]

 1 Disk Enclosure (DE) 2 Magnetic Disk 3 Spindle Motor 4 Dust Hole 5,6 Photoelectric Conversion Element 7 Counter 8 CPU 9 Register 10 Timer

Claims (7)

[Claims] 1. A disk enclosure, a first dust detecting means for detecting a dust amount at a predetermined position in the disk enclosure, and a second dust for detecting a dust amount in the disk enclosure when a spindle motor is rotating. Detection means, first control means for performing rotation start control of the spindle motor according to the detection output of the first dust detection means when the power is turned on, and the second dust detection when the spindle motor rotates. And a second control unit for controlling the rotation stop of the spindle motor according to the detection output of the unit. 2. The first dust detecting means comprises a dust measuring recess provided at a predetermined location in the disk enclosure, and a photoelectric conversion element for detecting the amount of dust in the recess. The magnetic disk drive according to claim 1. 3. The second dust detection means includes a pair of opposed photoelectric conversion elements provided in the disk enclosure, and a pair of opposed photoelectric conversion elements opposed to each other due to dust floating when the spindle motor rotates. 3. The magnetic disk device according to claim 1, further comprising a counting unit that counts the number of the dusts passing through the gap. 4. The first control means is configured to start rotation of the spindle motor when the amount detected by the first dust detection means is less than or equal to a predetermined value. The magnetic disk device according to any one of 1 to 3. 5. The first control means comprises a reporting means for reporting to the outside as an error when the amount detected by the first dust detecting means exceeds the predetermined value. The magnetic disk device according to claim 4. 6. The second control means is configured to stop the rotation of the spindle motor when the count output of the counting means in a predetermined unit time is larger than a predetermined number. The magnetic disk device according to claim 3. 7. The second control means has a reporting means for reporting an error to the outside when the count output of the counting means exceeds a predetermined number, as an error. Magnetic disk device.