JP2695922B2 - Magnetic disk drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention] (Industrial application field) The present invention relates to a magnetic disk drive provided with a transducer loading mechanism for recording and reproducing information on and from a recording disk as a magnetic recording medium. About.

(Prior Art) As shown in FIGS. 6 and 7, a Winchester-type magnetic disk device supports suspensions 7 and 9 having a magnetic head 3 at a tip end thereof by a carriage arm 11. The recording disk is loaded on the surface of the magnetic disk 1 by rotation.

A vertically extending fixed shaft 17 is mounted between the distal ends of the connecting plates 15 and 15 fixed above and below the drive motor 13, and the carriage boss is mounted around the fixed shaft 17 via a pair of upper and lower ball bearings 19. 21 is provided rotatably and the drive motor
The configuration is such that the carriage arm 11 is rotated around the fixed shaft 17 by the lever 13.

The respective carriage arms 11 are arranged at regular intervals along the axial direction of the carriage boss 21, and a pair of upper and lower suspensions 7 and 9 are provided at the tip of the carriage arm 11 so as to face the upper and lower surfaces of each magnetic disk 1. Let it. 23 is the fixed shaft
A preload spring for pressing the outer ring of the upper bearing 19 upward on the outer periphery of 17 is a housing for covering the outer periphery of the drive motor 13, the carriage boss 21, the magnetic disk 1 and the like. .

In this winchester-type magnetic disk device, the magnetic head 3 is in contact with the surface of the magnetic disk 1 while the rotation of the magnetic disk 1 is stopped. When the magnetic head 3 starts to glide over and reaches about 1/3 of the steady rotation speed, the magnetic head 3 starts to float from the magnetic disk surface due to a hydrodynamic bearing effect (dynamic pressure effect). When the rotation of the magnetic disk 1 stops,
As the number of rotations decreases, the flying height of the magnetic head 3 decreases, and finally the magnetic head 3 lands on the surface of the magnetic disk 1. Such flying and landing of the magnetic head 3 on the magnetic disk 1 is generally called CSS (Contact Start Stop). When the magnetic head 3 slides on the surface of the magnetic disk 1, the magnetic disk 1 is slightly damaged, but the level can be set to a level that does not cause any problem by employing an appropriate protective film, and this method is generally used.

(Problems to be Solved by the Invention) In recent years, in order to increase the recording density, the flying height of a magnetic head has been further reduced, and some flying heights of less than 0.2 μm have appeared. For this reason, magnetic disks having higher surface accuracy are required. However, if the surface accuracy is too good, the magnetic head is attracted to the magnetic disk surface when the rotation of the magnetic disk is stopped, and the magnetic disk and the magnetic head are damaged when the rotation is started.

In order to solve this problem, a method has been proposed in which the magnetic head is separated from the disk surface when the rotation of the magnetic disk is stopped, and the magnetic head is loaded on the magnetic disk after the magnetic disk reaches a steady rotation. However, this method has a disadvantage that extra time is required until recording and reproduction are performed due to the two-step operation of loading the magnetic head after the magnetic disk is completely rotated. In addition, since the magnetic force is loaded on the surface of the magnetic disk rotating at a relatively high speed in a steady rotation, an unstable vibration generated in the pitching direction is generated in the magnetic head subjected to the dynamic pressure effect. The rotation speed of the magnetic disk causes a resonance phenomenon to cause serious damage to the magnetic disk surface.

On the other hand, there is a method in which the magnetic head is loaded on the magnetic disk while the rotation of the magnetic disk is stopped, and then the magnetic disk is rotated. There is also the danger of causing adsorption as soon as possible.

The present invention solves such a conventional drawback, and in a high-density, low-flying magnetic disk drive, the time from the start of rotation of the magnetic disk to the time of recording / reproduction is not excessively increased, and the magnetic disk surface An object of the present invention is to provide a magnetic disk drive provided with a loading mechanism that prevents the magnetic head from being attracted.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the problems described above, the present invention provides a magnetic disk as a recording disk, a transducer for recording and reproducing information on and from the magnetic disk, When the rotation of the magnetic disk is stopped, the transducer is supported in a state of being separated from the disk, and after the rotation of the magnetic disk is started, the support is released before the disk reaches a steady rotation, and the transducer is moved. And a mechanism for loading so as to make contact with the disk.

(Operation) While the magnetic disk as the recording disk stops rotating, the magnetic head as the transducer is supported at a position away from the magnetic disk surface. In this state, before the magnetic disk starts rotating, and before the magnetic head is brought into a rotating state in which the magnetic head can float by a very small amount, the support of the magnetic head is released and loading is performed. As a result, the magnetic head is released and slides on the rotating magnetic disk surface. When the rotation of the magnetic disk increases and reaches a steady state circuit, the magnetic head floats by a very small amount from the surface of the magnetic disk due to the hydrodynamic bearing effect (dynamic pressure effect), thereby enabling recording and reproduction. Thus, when the magnetic head is loaded,
Since the magnetic disk slides in contact with the magnetic disk surface rotating at a low speed, the magnetic disk surface is prevented from being attracted. Also,
At the time of the contact, the magnetic disk rotates at a low speed, so that the magnetic disk does not resonate with the vibration of the magnetic head in the pitching direction and damage to the magnetic disk surface is prevented.

Embodiment An embodiment of the present invention will be described below with reference to FIGS.

FIGS. 1 to 3 show a multi-stage magnetic disk drive, and FIG. 4 shows a single unit. Suspensions 7 and 9 having the magnetic head 3 are supported by a carriage arm 11, and the carriage arm 11 is disposed at the same interval as the magnetic disk 1 along the axial direction of the carriage boss 21. The magnetic head 3 is opposed to and close to the upper and lower sides of the magnetic disk 1.

The carriage boss 21 is rotatably provided around a fixed shaft 17 by a bearing, and is rotated together with the carriage arm 11 by a drive motor 13. On the disk shaft 27 supported in parallel with the fixed shaft 17, the magnetic disks 1 are arranged in multiple stages at regular intervals in the axial direction, and are provided corresponding to the respective carriage arms 11. Each such carriage arm 11
Are integrally rotated by a drive motor 13, and the magnetic head 3 at the tip thereof is moved and positioned with respect to the magnetic disk 1 to record and reproduce information.

The magnetic head 3 is urged by the suspensions 7 and 9 toward the upper and lower surfaces of the magnetic disk 1 during recording and reproduction. Further, the magnetic head 3 is configured such that when the magnetic disk 1 rotates, a small amount of the magnetic head floats and separates from the surface of the magnetic disk 1 due to a fluid bearing effect.

Next, a description will be given of the head supporting means 5 for separating the magnetic head 3 from the magnetic disk 1 and releasing the magnetic head 3 from the magnetic disk 1. On the outer peripheral side of the magnetic disk 1 where the magnetic head 3 is located, a load arm 31 that rotates around a load shaft 29 parallel to the fixed shaft 17 is provided. At the tip of the load arm 31, tapered surfaces 33, 35 capable of lifting the suspensions 7, 9 are formed, and each load arm 31 is rotated to the suspension 7, 9 side by a stepping motor or the like, and the suspensions 7, 9 Are lifted up by the tapered surfaces 33 and 35, thereby separating the magnetic head 3 from the surface of the magnetic disk 1 (FIG. 3). Also, load arm 31
The magnetic head 3 can be loaded onto the surface of the magnetic disk 1 by rotating it outward around 29 and releasing it from the suspensions 7 and 9 (FIG. 2). 37 is a bracket for supporting the load shaft 29, and is attached to the housing.

When the rotation of the magnetic disk 1 is stopped, the head support means 5 lifts the suspensions 7 and 9 by the load arm 31 to support the magnetic head 3 away from the surface of the magnetic disk 1 as shown in FIG. It operates to be in a state. At this time, the magnetic head 3 is at the position A in FIG. 5 separated from the surface of the magnetic disk 1.

Next, before the magnetic disk 1 starts to rotate and thereafter reaches a steady rotation, that is, before the magnetic head 3 is brought into a rotating state in which the magnetic head 3 can fly a small amount above the surface of the magnetic disk 1 after the rotation is started, the suspension 7 by the load arm 31 is rotated. , 9 are released. As a result, the magnetic head 3 comes into contact with the surface of the magnetic disk 1, and the magnetic head 3 slides on the surface of the rotating magnetic disk 1. At this time, the magnetic head 3 falls on the surface of the magnetic disk 1 rotating at a low speed. However, since the magnetic head 3 is rotating at a low speed, the adsorption phenomenon does not occur, and the rotation speed of the magnetic disk 1 is not so high. Since the magnetic head 3 is not fast, unstable vibration in the pitching direction of the magnetic head 3 hardly resonates and does not damage the magnetic disk 1 or the surface of the magnetic head 3.

It should be noted that a normal magnetic disk requires about 20 seconds from the start of rotation until reaching normal rotation. Of these, 1 /
Until about 6 to 7 seconds, which is about three times, the magnetic head slides on the surface of the magnetic disk and does not float. Therefore,
In this embodiment, the magnetic head 3 may be brought into contact with the surface of the magnetic disk 1 within 6 to 7 seconds after the rotation of the magnetic disk 1 is started.

Thereafter, until the magnetic disk 1 reaches the steady rotation, the magnetic head 3 gradually floats due to the hydrodynamic bearing effect. When the steady rotation is reached, the magnetic head 3 becomes the B position where recording and reproduction can be performed by the magnetic head 3.

Next, when the rotation of the magnetic disk 1 is stopped, when the magnetic head 3 is floating at the position B from the surface of the magnetic disk 1, the load arm 31 is moved from the outside to the magnetic disk 1.
, The suspensions 7 and 9 are lifted by the tapered surfaces 33 and 35, and the magnetic head 3 is moved to the magnetic disk 1.
It is supported at the position A separated from the surface (FIG. 3). For this reason, even if the rotation of the magnetic disk 1 is stopped and the floating force of the magnetic head 3 due to the hydrodynamic bearing effect is lost, the magnetic head 1 is supported by the load arm 31 and the distance A from the surface of the magnetic disk 1 is maintained.

As described above, the magnetic head 3 is separated from the magnetic disk 1 when the magnetic disk 1 is stopped rotating, so that the magnetic head 3 does not stick to the magnetic disk 1 and the rotation start is performed without any trouble. Will be Also, when the magnetic disk 1 stops rotating, the load arm 31 supports the suspensions 7 and 9 when the magnetic head 3 is floating, so that the magnetic head 3 does not come into contact with the magnetic disk 1 and this contact state exists. Is only at the start of rotation, the sliding amount of the magnetic head 3 is reduced, and the reliability of the apparatus can be further improved.

Further, after the magnetic disk 1 rotates, the magnetic head 3 can contact and load the magnetic disk 1 at the time of low-speed rotation before reaching the steady rotation, so that the magnetic head 3 is brought into contact after reaching the steady rotation, or the rotation is started after the contact. As compared with the conventional two-stage operation, the time until recording and reproduction is reduced.

If the magnetic head 3 is moved away from the magnetic disk 1 by operating the head supporting means 5 using the back electromotive force at the time of deceleration of the drive motor 13 for rotating the magnetic disk 1, an emergency such as a power failure may occur. However, it is possible to prevent the magnetic head 3 from being damaged at the time of a power failure or the like and to reduce power consumption. Since the voltage of the back electromotive force is proportional to the number of rotations of the motor, the back electromotive force can be effectively used by using a mechanism for operating the head supporting means 5 during the floating of the magnetic head having a high number of rotations as in this embodiment. .

[Effects of the Invention] As described above, according to the present invention, while the rotation of the recording disk is stopped, the transducer is supported in a state of being separated from the recording disk surface, and after the rotation is started, the transducer is placed on the recording disk surface. Since the separation support is released before the rotation state in which the recording disk can be floated, it is possible to prevent the transducer from adsorbing to the recording disk when the recording disk rotates, and to operate the transducer at a low speed. Since the rotating disk is brought into contact with the recording disk, resonance due to vibration of the transducer in the pitching direction during loading can be effectively prevented, and damage to the recording disk can be avoided. Also, after the rotation of the recording disk,
Before reaching a steady rotation, the transducer can be quickly loaded on the recording disk surface, so that the time until recording / reproducing is reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of a magnetic disk drive showing one embodiment of the present invention, FIGS. 2 and 3 are enlarged side views showing the operation of the main part, FIG. 4 is a partial perspective view of another embodiment, FIG. 5 is an operation diagram of a magnetic head for a magnetic disk, FIG. 6 is a sectional view of a conventional magnetic disk device, and FIG. 7 is a perspective view of the conventional example. 1 magnetic disk (recording disk) 3 magnetic head (transducer) 5 head support means (mechanism for loading the transducer)

Claims (1)

(57) [Claims] 1. A magnetic disk as a recording disk, a transducer for recording and reproducing information on and from the magnetic disk, and when the rotation of the magnetic disk is stopped, the transducer is supported while being separated from the disk. A mechanism for releasing the support and loading the transducer so as to contact the disk after the magnetic disk starts rotating before the disk reaches a steady rotation.