JPH05109223A - Css system magnetic disk driving device - Google Patents

Abstract

PURPOSE:To confirm secure operation of a lock function in a landing/shipping zone. CONSTITUTION:A landing/shipping zone indicator gap is provided in the landing/ shipping zone A of a magnetic disk 6. Forward and reverse signals for driving an actuator 17 in the directions of arrows I and J at the time of locking the actuator are alternately outputted by a lock detecting means 20. Then, during outputting at least either of the signals, when the landing/shipping zone indicator gap is not periodically detected from a read signal of a magnetic head 5, an alarm signal is outputted via an interface control part 8 and an interface controller 1 to a host device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CSS type magnetic disk drive having a head lock function.

[0002]

2. Description of the Related Art Generally, a small magnetic disk drive is
It is sealed with a metal enclosure to prevent dust from entering the mechanism. In addition, the pressing load of the magnetic head (hereinafter referred to as the head) on the magnetic disk surface is reduced to keep the head in contact with the disk surface while the magnetic disk (hereinafter referred to as the disk) is stopped, and the disk rotates as the disk speed increases. A contact start stop (hereinafter referred to as CSS) method in which the head floats by the lift force due to the air flow between the head and the head is used.

In this type of magnetic disk drive, the head does not float until the rotation of the disk reaches a certain number of revolutions, but the head comes into contact with the surface of the disk and slides. If this state is repeated, the characteristics of the disk surface change due to wear of the disk surface, or the surface is scratched, and the durability and reliability of the magnetic disk drive device deteriorate. Therefore, in a CSS type magnetic disk drive, an area called a landing shipping zone is provided in addition to a data area for recording information on the disk surface, and the head is used when the disk slows down and stops. The head is slid on the landing shipping zone, and the head slides on the disk surface in this area to stop the contact.

Further, after the head is moved to the landing shipping zone and stopped, the actuator for driving the head is locked by a lock solenoid so that the head does not move to the data area due to vibration or impact.

[0005]

In the conventional CSS type magnetic disk drive, since the mechanical portion such as the lock solenoid is surrounded by the metallic enclosure, the operation after the magnetic disk drive is assembled is completed. During the test, it was not possible to visually confirm whether or not the lock function was operating reliably in the landing shipping zone.

The present invention can confirm that the lock function is operating reliably in the landing shipping zone.
It is an object to provide an S type magnetic disk drive device.

[0007]

In order to achieve the above object, in a CSS type magnetic disk drive of the present invention, a landing shipping zone indicator gap is provided in the landing shipping zone, and a forward drive for driving an actuator at the time of locking is provided. The lock detection means alternately outputs the reverse signals and periodically outputs the alarm signal when the landing shipping zone indicator gap is not detected from the read signal of the magnetic head while at least one of the signals is being output. ..

[0008]

The lock detecting means of the CSS type magnetic disk drive constructed as described above alternately outputs the forward and reverse signals for driving the actuator when locked. When the actuator is locked and the magnetic head is in the landing shipping zone, the lock detecting means can detect the landing shipping zone indicator gap periodically. On the other hand, if the actuator is not locked, the lock detection means cannot periodically detect the landing shipping zone indicator gap and therefore outputs an alarm signal.

Therefore, according to the present invention, it can be confirmed that the lock function operates reliably in the landing shipping zone.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. The elements common to the drawings are given the same reference numerals.

FIG. 1 is a block diagram of a CSS type magnetic disk drive according to an embodiment of the present invention. The interface controller 1 exchanges data with the host, decodes and executes commands, transfers data, and controls.

The data separator 2 outputs the write NRZ data sent from the interface controller 1 to 2-
The data is converted (encoded) into data such as a 7RLL code and the read data from the pulse detector 3 is returned to NRZ data.

The pulse detector 3 reads from the magnetic head 5 and converts the analog waveform amplified by the first stage amplifier 4 into a pulse signal. In addition, the servo signal for conversion positioning included in the read signal is detected. Signals are also sent to the servo timing generation circuit 10 and the servo pattern detection circuit 11.

The first-stage amplifier 4 is also known as Read / Write.
Also called an amplifier, write data is converted into a current and supplied to the magnetic head 5. Further, at the time of reading, the read analog signal is amplified and sent to the pulse detector 3.

The magnetic head 5 converts the pulse train of the write signal into a magnetic signal and records it on the magnetic film on the surface of the magnetic disk 6, and at the time of reading, converts the data on the magnetic disk into an electric signal, and the first stage amplifier 4 Send to.

The magnetic disk 6 has a magnetic film formed by coating, plating, or vapor-depositing a magnetic material on the surface of a disk mainly composed of a substrate made of aluminum. Data is recorded on the magnetic disk 6 according to the rate at which the magnetic film is magnetized. A landing shipping zone A and a data area B for recording data are provided on the disk surface of the magnetic disk 6.

The buffer memory 7 is an IC memory (SRAM) for temporarily storing the data sent from the host and the data read from the magnetic disk 6.

The interface control unit 8 issues an operation command to the interface controller 1 and exchanges control signals with the mechanical control unit 9.

The mechanical control unit 9 is a central processing unit 9a (hereinafter CPU).
9a) and a memory 9b (hereinafter referred to as MEM 9b), and controls the rotation command of the spindle motor 13, controls the voice coil motor 16 (hereinafter referred to as VCM 16), and controls the mechanism of the magnetic disk device. .. or,
The CPU 9a follows the steps of the control program stored in the MEM 9b, and the lock detecting means 20 according to the present invention.
become.

The servo timing generation circuit 10 is a circuit for generating a timing for reading servo data for positioning the magnetic head 5 embedded between the sectors of the track from the pulse train of the signal read from the magnetic disk 6.

The servo pattern detection circuit 11 detects a servo pattern for positioning the magnetic head 5 from the read analog signal and sends it to the mechanical control section 9.

Based on commands from the spindle motor drive circuit 12 and the mechanical control unit 9, the spindle motor 13 is turned on and off to keep the rotation of the spindle motor 13 at a constant speed.

The spindle motor 13 is a motor for holding and rotating the magnetic disk 6 fixed to its shaft.

The D / A converter 14 converts the digital signal output from the mechanical control unit 9 into an analog voltage and converts it to V.
It is sent to the CM drive circuit 15.

The VCM drive circuit 15 is the D / A converter 1
A current is supplied to the coil of the VCM 16 that moves the actuator 17 to which the magnetic head 5 is attached based on the analog voltage value from 4. Further, the value of the flowing current is detected and fed back to the mechanical control unit 9 so as to keep the current appropriate.

The VCM 16 has a flowing current direction, and
The actuator 17 is driven according to the strength, and the magnetic head 5
Is moved to an arbitrary track on the magnetic disk 6 and positioned on the track.

The actuator 17 moves the magnetic head 5 on the magnetic disk 6 according to the driving force of the VCM 16.

The lock solenoid 18 is a coil for fixing the magnetic head 5 so that the magnetic head 5 does not move when the VCM 16 is not driven (when the magnetic disk drive is not operating), and locks (fixes) the actuator 17 when no current is applied to the coil. Then, when the VCM is driven, the coil allows current to flow to release the lock.

The lock solenoid drive circuit 19 is a drive circuit for supplying a current to the lock solenoid 18.

FIG. 2 is a front view showing the recording surface of the magnified magnetic disk, in which a pattern on a disk is developed and an arc is drawn linearly. The data area B is a portion of the data track where data is written. Since the outer guard band C and the inner guard band D detect that the magnetic head 5 has deviated from the data area B, tracks are formed by a pattern different from that of the data area B. In the landing shipping zone A, a signal pattern different from the data area B and each guard band is written.

The traveling direction of the magnetic head 5 moves from the left side to the right side. Index gap 6 shown in range E
Reference numeral a denotes an erase portion provided in each of the guard bands C and D of the magnetic disk 6 and the landing shipping zone A at one place in one round. The positioning servo pattern writing portions 6b indicated by the range F are provided in 34 places in this embodiment within one round of the disk surface. The data part 6c indicated by the range G is provided in 34 places in total between the positioning servo pattern writing parts 6b in one track, one of which corresponds to one sector, and in this embodiment, there are 34 sectors in one track. .. The landing shipping zone indicator gap 6d shown by the range H is composed of two erase parts provided for each sector, and is provided in the landing shipping zone A.

A signal pattern of the reference frequency is written in the shaded area in FIG.

FIG. 3 is a time chart of one embodiment,
(A), (B), and (C) show the outputs of the magnetic head, pulse detector, and servo timing generation circuit, respectively.

Next, the operation will be described. When the spindle motor is started, the magnetic head 5 is locked in the landing / shipping zone A, and when the magnetic disk 6 starts to rotate and reaches a steady rotation speed, the magnetic head 5 responds to the magnetic signal written on the magnetic disk surface. Figure 3 (A)
The READ waveform shown in is output. This READ waveform is converted by the pulse detector 3 into the pulse train shown in FIG. 3 (B) corresponding to the peak position of the waveform, and a continuous pulse is output at the portion where the signal pattern of the fundamental frequency is written, No pulse is output in the erase section.
This pulse train is input to the servo timing generation circuit 10. First, the index gap 6a shown in FIG. 2 is detected, and when the detection of the index gap 6a is completed, a timing count is performed in synchronization therewith, and the positioning servo pattern writing section 6b appearing next is detected. Done. Positioning servo
When the pattern writing section 6b is normally detected,
After that, the timing count is calculated from the timing count by the index gap 6a to the positioning servo.
The timing count is synchronized with the pattern writing unit 6b.

When the above operation is completed normally, the head
Move on to lock detection operation. In this step, the mechanical control unit 9 becomes the lock detecting means 20. Lock detection means 20 is VC
A forward signal and a reverse signal are alternately output to the M drive circuit 15. If the lock solenoid 18 is not energized, the actuator 17 remains locked, so that the lock detection means 20 causes the servo timing generation circuit 1 to operate.
The landing shipping zone indicator gap 6d can be regularly confirmed through 0 to detect that the magnetic head 5 is locked in the landing shipping zone A. When the lock solenoid 18 is energized, the actuator 17 moves on the magnetic disk 6 in the arrow I direction by the forward signal, and moves in the arrow J direction by the reverse signal. Therefore, the lock detecting means 20 cannot periodically confirm the landing shipping zone indicator gap 6d and outputs an alarm signal to the interface control section 8. Further, the alarm is notified to the host through the interface controller 8 and the interface controller 1.

The above is the operation of detecting the head and the lock, and this apparatus is repeatedly performed at the time of in-house inspection to confirm the stable normal operation of its function. In addition, even after shipment, the self-diagnosis at the time of startup is always performed at the time of startup.

When it is confirmed by the head lock detection operation that the magnetic head 5 is locked in the landing shipping zone A, the mechanical control unit 9 energizes the lock solenoid 18, unlocks the actuator 17, and releases the magnetic head. 5 starts moving in the direction of arrow I. Then, after the return-to-zero (zero track detection) operation is completed, the drive becomes ready and the host can access it.

[0038]

Since the present invention is configured as described above, it has the following effects.

By providing the landing shipping zone indicator gap in the landing shipping zone and outputting the alarm signal when the lock detection means cannot detect the landing shipping zone indicator gap at the time of locking the actuator, the lock function can be improved. You can confirm that it is operating reliably in the landing shipping zone.

[Brief description of drawings]

FIG. 1 is a block diagram of a CSS type magnetic disk drive according to an embodiment of the present invention.

FIG. 2 is a front view showing a recording surface of an enlarged magnetic disk.

FIG. 3 is a time chart of an example.

[Explanation of symbols]

 5 magnetic head 6 magnetic disk 17 actuator 20 lock detection means

Claims (1)

[Claims] 1. In a CSS type magnetic disk drive in which an actuator is locked when a read / write operation is not performed and a magnetic head is fixed to a landing shipping zone on a magnetic disk surface, a landing shipping zone indicator gap is set to a landing shipping zone. When the actuator is locked, the forward and reverse signals that drive the actuator are alternately output, and an alarm signal is output when the landing shipping zone indicator gap is not detected periodically from the read signal of the magnetic head while at least one of the signals is being output. A CSS type magnetic head driving device comprising lock detecting means for outputting.