JP2658447B2 - Slider loading method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slider loading method used in a magnetic disk drive used for information processing.

2. Description of the Related Art Conventionally, in a magnetic disk device, in particular, a hard disk drive device, at the time of startup, the disk starts to rotate with the slider in contact with the disk surface, causing the slider to fly by airflow generated on the disk surface, and immediately before stopping the disk. Most of them have a CSS (contact start / stop) type mechanism that stops while the slider and the disk surface are in contact with each other. However, when the C.S.S.S. operation is performed, the slider and the disk surface are in contact with each other, so that the slider and the disk are rubbed, and the disk, the flying surface of the slider, the disk, and the like are damaged. In recent years, for higher density,
In order to further reduce the flying height of the slider and the disk, it has been considered to smooth the disk. However, if the disk is smoothed, the slider and the disk are likely to be attracted.

Therefore, a method has been developed in which the flying slider is caused to fly without contact with the disk surface. The method will be described below. When the disk is stopped, the slider is located at a certain distance from the disk. Next, after the disk is rotated at a constant speed, the slider is moved closer to the disk surface. When the distance between the slider and the disk reaches a certain distance, dynamic pressure starts to be generated on the slider, and the slider keeps a certain distance from the disk (hereinafter, this state is abbreviated as a floating state). At this time, the slider flies at a position where the dynamic pressure and the external load are balanced.

A conventional magnetic disk drive using the above method will be described with reference to FIGS. 4 and 5. FIG. In FIG.
Reference numeral 1 denotes a flexure constituted by a leaf spring,
Is fixed to an arm 5 which is movable in a direction crossing the data track recorded in the data track. At this time, as shown in FIG. 5, the flexure 1 is attached to the arm 5 so that the longitudinal direction of the flexure 1 and the longitudinal direction of the arm 5 have a certain angle. In FIG. 4, reference numeral 2 denotes a gimbal formed by a thin plate provided at the tip of the flexure 1, which has four radially formed plates, each having a constricted portion. Reference numeral 3 denotes a floating rail having a floating surface, and a slider having a rail orthogonal to the floating rail. The slider 3 is fixed to the flexure 1 via a gimbal 2 so that the longitudinal direction of the floating rail and the flexure 1 are parallel. . The gimbal 2 twists at the constricted portion during the rolling and pitching movements of the slider, and the slider 3 flies while following the disk 6. A flexure pressing member 4 is formed by bending a wire made of a shape memory alloy into a V-shape, and is fixed to the arm 5. The shape of the flexure pressing member 4 is stored so that the flexure 1 is displaced in a direction to bring the flexure 1 closer to the disk 6 at the time of shape recovery. When a current flows through the flexure pressing member 4, the flexure pressing member 4 itself generates heat and recovers its shape. At this time, the loading operation is performed by changing the flexure 1 in a direction approaching the disk 6 and causing the slider 3 to float on the disk 6.

Next, a voice coil motor (hereinafter referred to as VCM) for moving the arm 5 across the track direction will be described with reference to FIG. In FIG. 5, reference numeral 7 denotes a shaft rotatably supporting the arm 5, and the arm 5 rotates about the shaft 7 as an axis. Reference numeral 8 denotes a bobbin integrated with the arm 5, on which a coil made of a copper wire or the like is wound. 9
Is a yoke constituting a magnetic circuit. The VCM drives the arm 5 from the outer circumference to the inner circumference of the disk 6 by moving the bobbin 8 in the yoke 9 by flowing a current through a coil wound on the bobbin 8, and flowing a current in the opposite direction. To drive from the inner circumference to the outer circumference. Here, 10 is a locus from the outer circumference to the inner circumference of the slider 3.

The reason why the flexure 1 is attached to the arm 5 so as to have a certain angle will be described. This is achieved by mounting the flexure 1 at an angle to the arm 5 as shown in FIG. 4 so that the angle between the floating rail provided on the slider 3 and the air flow entering the slider (hereinafter referred to as the yaw angle). (Abbreviation) is set to 0 degrees as much as possible, and the slider 3 is floated on the disk 6 with a constant flying height as much as possible in the inner peripheral portion and the outer peripheral portion. For example, when the flexure 1 is mounted at an angle with respect to the arm 5, the yaw angle is 0 degree at the inner periphery of the disk 6, but is around 1.5 degrees at the outer periphery. When the flexure 1 is quickly attached to the arm 5, the yaw angle is 0 degree at the inner periphery of the disk 6, and 3 to 6 degrees at the outer periphery.
Therefore, when the flexure 1 is attached to the arm 5 at an angle, the displacement of the yaw angle is small, and the flying height can be made almost the same at the inner peripheral portion and the outer peripheral portion of the disk 6.

Immediately after the slider 3 is levitated, a tensile force is applied to the slider 3 such that the slider 3 is pulled in the same direction as the rotation direction of the disk 6 by the airflow generated on the surface of the disk 6. Since the direction of the pulling force and the straight line connecting the fulcrum of the pulling force and the shaft 7 become non-parallel, a torque is generated in the arm 5 in the direction of the slider 3 toward the center of the disk 6 around the shaft 7. This causes the arm 5 to slightly move in the direction of the disk 6. Then, the floating surface of the slider 6 becomes non-parallel to the disk 6, the floating of the slider 3 becomes unstable, the slider 3 comes into contact with the disk 6, and the slider 3 and the disk 6 are also damaged. . If this phenomenon occurs many times, there is a problem that data cannot be read from or written to the disk 6. This phenomenon hardly occurs when the slider completely enters the floating state, and often occurs when the slider is lifted.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and a method of loading a slider that prevents the slider from moving toward the center of the disk when the slider floats above the disk, so that the slider does not come into contact with the disk. It is intended to provide.

Means for Solving the Problems To achieve this object, in a state where the support means is fixed so as not to move in the radial direction of the disk, the support means is moved toward the disk, and the slider is brought closer to the disk. did.

Operation With this configuration, even if an unnecessary force is applied to the slider immediately before the slider is loaded, the slider does not move in the radial direction of the disk due to the external force.

Embodiment FIG. 1 is a configuration diagram showing an embodiment of a magnetic disk drive using a slider loading method of the present invention.
In FIG. 1, those having the same numbers as those in FIGS. 4 and 5 have the same functions. In FIG. 1, reference numeral 11 denotes a spindle motor on which the magnetic disk 6 is mounted, 12 denotes a spindle motor driving circuit for driving the spindle motor 11 to rotate,
Is a central processing unit for controlling the system of the magnetic disk drive, 14 is a loading drive unit which is a drive circuit for passing a current to the flexure pressing member 4, 15 is a head amplifier, and the head amplifier 15 amplifies a signal to be recorded on the disk 6. Or amplifies the reproduction output read from the disk 6 by the head mounted on the slider 3. 16 is a servo signal detection circuit for detecting position information for positioning the slider 3 on the magnetic disk, 17 is a control circuit such as phase compensation for positioning control, 18 is a constant voltage circuit for generating a constant reference voltage, 19 and 20 are analog switches, 21 is VCM
VCM driver to drive current to the coil of bobbin 8
Reference numeral 2 denotes an interface circuit with a higher-level system.

The operation of the above configuration will be described. When the power of the magnetic disk drive is turned on or when an operation command signal is issued from a higher-level system, it is received by the interface 22 and sent to the central processing unit 13. When the central processing unit 13 detects the signal, it issues an operation command to the spindle motor driving circuit 12,
Numeral 12 sends an electric current to the spindle motor 11 to drive the spindle motor 11 to rotate the magnetic disk 6.
Then, when the rotation speed of the disk 6 becomes equal to or more than a certain rotation, the central processing unit 13 turns off the analog switch 19, turns on the analog switch 20, and supplies the output of the constant voltage circuit 18 to the VCM driver 21. When a constant voltage is applied to the VCM driver 21, a current flows through the VCM, the arm 5 mounted on the VCM moves in the outer peripheral direction of the disk 6, and the slider 3 is prevented from coming out of the disk 6. It comes into contact with a stopper (not shown) provided. At this time, the current continues to flow through the VCM, the arm 5 is pressed against the stopper, and the arm 5 is fixed. Then the central processing unit
13 issues an operation command signal to the loading drive device 14,
As a result, the loading drive circuit 14 supplies a current to the flexure pressing member 4. Then, the flexure pressing member 4 itself generates heat to cause shape recovery. The flexure pressing member 4 performs a loading operation by pressing the flexure 1 to change the magnetic disk 6 in a direction of approaching and causing the slider 3 to float on the disk 6. During the loading operation, the arm 5 is constantly pushed by the stopper and is in a fixed state, so that it is possible to prevent the arm from moving toward the disk 6 immediately after the floating state as in the related art. Slider 3
Is in a floating state, the central processing unit 13 disconnects the analog switch 20 to prevent a constant current from flowing through the VCM.
Whether the slider 3 has floated is determined by the central processing unit 13 whether the output from the head amplifier 15 has exceeded a predetermined value. At this time, the torque applied to the slider 3 is measured just before the flying state, and the constant current value is set so that the arm can be fixed to such an extent that the arm cannot be moved by the torque. After the loading operation is completed,
The servo information of the head on the slider 3, the head amplifier 15
The servo signal detection circuit 16 is detected via the
The central processing unit 13 turns off the analog switch 20
The analog switch 19 is turned on and supplied to the VCM driver 21 to perform a positioning operation according to the track information of the magnetic disk 6. In this embodiment, the central processing unit 13 determines whether or not the slider 3 has floated, based on whether or not the output from the head amplifier 15 has exceeded a predetermined value. After that, the loading time from when the slider 3 floats up may be measured, and the central processing unit 13 may count the loading time with a timer so that the constant current does not flow through the VCM.

2 and 3 show another embodiment of the present invention.
Reference numeral 23 denotes a lock portion for locking the arm 5, reference numeral 24 denotes a lock arm for locking the lock portion 23 of the arm 5, reference numeral 25 denotes a lock release constituted by, for example, a solenoid for separating the lock arm 24 from the lock portion 23. Device. That is, before the magnetic disk drive is driven, the slider 3 and the disk 6 are in a non-contact state, and the lock arm 24 restrains the lock portion 23 of the arm 5.

In FIG. 3, when the power of the magnetic disk drive is turned on or an operation command signal is issued from a higher-level system, it is received by the interface 22 and received by the central processing unit 13.
Sent to When the central processing unit 13 detects the signal,
The central processing unit 13 issues an operation command to the spindle motor drive circuit 12, and the spindle motor drive circuit sends a current to the spindle motor 11 to drive the spindle motor 11 and rotate the magnetic disk 6. When the number of rotations of the disk 6 exceeds a certain value, the central processing unit 13
Sends an operation command signal to the loading drive device 14, whereby the loading drive circuit 14 supplies a current to the flexure pressing member 4. Then, the flexure pressing member 4 itself generates heat to cause shape recovery. The flexure pressing member 4 performs a loading operation by pressing the flexure 1 to change the magnetic disk 6 in a direction approaching and to cause the slider 3 to float on the disk 6. When the slider 3 is in the floating state, the central processing unit 13 drives the lock release device 25 to displace the lock arm 24, thereby
The arm 5 is movable in the track direction by separating the lock 24 from the lock portion 23. That is, when loading the slider 3, the lock arm 24 restrains the lock portion 23 of the arm 5, thereby fixing the slider 3 in the track direction, canceling the rotational force generated in the slider 3 in the inner circumferential direction, and It is stably loaded on the disk 6 and does not come into contact with the disk surface. Whether the slider 3 has floated is determined by the central processing unit 13 whether the output from the head amplifier 15 has exceeded a predetermined value. The second
In this embodiment, the analog switches 19 and 20 and the constant voltage circuit 18 are not required. In the first embodiment, the VCM
Although the arm 5 is fixed by applying a constant voltage to the driver 21, it is needless to say that the current can be controlled.

According to the present invention, the slider is loaded by moving the support means toward the disk and moving the slider closer to the disk while the support means is fixed so as not to move in the radial direction of the disk. The slider does not move in the radial direction of the disc due to external force even if an unnecessary force is applied to the slider immediately before the recording, and the slider loses its balance and strongly contacts the disc during loading, affecting recording or playback. Such a scratch can be prevented from entering the disc or the slider.

[Brief description of the drawings]

FIG. 1 is a block diagram of a magnetic disk drive using a slider loading method according to an embodiment of the present invention;
FIG. 2 is a configuration diagram of a magnetic disk device using a slider loading method according to another embodiment of the present invention, FIG. 3 is a block diagram of the same, and FIGS. 4 and 5 are configurations of a conventional magnetic disk device. FIG. 1 Flexure 3 Slider 4 Flexure pressing member 5 Arm 6 Disk 13 Central processing unit 14 Loading drive unit 18 Constant voltage circuit 19, 20 Analog switch 24 Lock arm 25 ... Lock release device.

Claims (1)

(57) [Claims] 1. A slider loading means for loading a slider on a disk by disposing a slider in advance from a disk, moving a support means for supporting the slider in the disk direction, and loading the slider on the disk. A slider loading method comprising: moving the support means toward the disk in a state where the slider is fixed so as not to move in the radial direction to bring the slider closer to the disk.