JP2534006Y2 - Magnetic disk drive - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk drive having a function of loading and unloading a magnetic head.

[0002]

2. Description of the Related Art A magnetic disk drive uses a floating head slider having a magnetic head mounted on one end surface thereof.
This floating head slider flies above the disk by the dynamic effect of high-speed airflow generated by high-speed rotation of the disk, and performs recording and reproduction while maintaining a slight gap between the magnetic head and the recording medium. Gimbal springs that follow the disk surface protrusions and undulations while keeping the spacing constant while maintaining free movement in the pitch, roll, and perpendicular directions to the disk surface, as well as the flying height of the floating head slider Is added to the gimbal spring to control the magnetic head and move the magnetic head over an arbitrary recording track.

On the other hand, in the current magnetic disk drive, as a start / stop method, a floating head slider and a disk are installed in contact with each other when the disk stops rotating.
Start the rotation of the disk, levitate the floating head slider with the increase in the number of rotations, perform normal operation, and when the disk stops, let the floating head slider land on the disk again by lowering the disk rotation number, so-called, Contact start stop (CSS)
The method is the mainstream. In the CSS system, the floating head slider and the disk surface are operated through each stage of contact, low-speed sliding, separation, low-speed sliding, and contact, which may cause friction and wear problems. A head crash may occur due to the frictional hair.

[0004]

Although the CSS system has an advantage that the structure of the mechanism is simple, it has the following problems. That is, the first problem is a problem of contact sliding that inevitably occurs during CSS. When the rotation speed of the disk reaches a certain speed or more, the floating head slider generates sufficient levitation force, so that the floating head slider and the disk surface are kept in non-contact. The levitation force acting on the head slider is small,
As a result, a state in which the floating head slider and the disk slide while contacting each other occurs. Such contact sliding also occurs when the disk stops, in which case the floating head slider transitions from a fluid lubricated state to a contact sliding state.

[0005] Usually, the floating head slider is made of a very hard material such as ceramic. On the other hand, the disk has a protective film made of carbon or the like to protect the magnetic recording layer, and a lubricant on the surface to reduce the frictional resistance during contact sliding with the floating head slider and to suppress wear. However, due to the characteristics of magnetic recording, since they are formed of a thin film, their hardness is smaller than that of a floating head slider. Therefore, there is a problem of friction and wear at the time of contact sliding, and fine friction and wear powder generated at this time may hinder stable movement of the floating head slider, possibly leading to head crash.

A second problem is that the slider lubrication surface of the floating head slider, which is required to have a further lower flying height in the future, is required to have extremely smooth finishing accuracy, and at the same time, the disk surface has a lower floating height. The demand for high flatness that does not hinder the amount may cause the floating head slider and the disk to be attracted when the disk is stopped. Once suction occurs, the frictional force increases rapidly, making it difficult to start the disk.

Therefore, in order to avoid the above problems,
There is a need for a disk drive start / stop system in which the floating head slider and the disk surface always operate without contact. This involves loading the floating head slider, which is mounted on the floating head slider support, through the process of approaching the surface of the magnetic disk medium, and moving the floating head slider away from the surface of the magnetic disk medium by the force provided by some mechanism. Unloading is required.

The most common loading / unloading operation is, as is well known, provided with a floating head holding mechanism for holding a floating head slider support in the vicinity of the outermost periphery of a magnetic disk medium. By having a structure having an inclined surface inclined in the outer circumferential direction of the magnetic disk medium, the floating head slider support that slides on the inclined surface of the floating head holding mechanism is moved up and down in accordance with the movement of the floating head slider support. This is realized by the ramp load method.

However, in the ramp load method, since the floating head holding mechanism and the floating head slider support are left in contact with the apparatus in a stopped state, the static friction force at the contact point between the two at the start of the loading operation is increased. Therefore, it is necessary to supply a large electric power to the positioner actuator in order to perform the loading operation over the static friction force.

However, supplying a large current at the start of operation has two problems. The first problem is that when a large torque is generated with a large current, the moving speed of the floating head slider support after the operation starts increases, and therefore, the formation of the air lubricating film on the floating head slider during loading is not performed well. The risk of contact of the head medium is increased. The second problem is that, particularly in a small magnetic disk device, the starting torque itself is not promoted due to the limitation of the allowable current, which makes starting itself difficult.

An object of the present invention is to solve the above problems and to provide a magnetic disk drive having a load / unload mechanism that can be started with a low current.

[0012]

According to the present invention, there is provided a gimbal spring comprising a floating head slider, a tongue-shaped leaf spring supporting the floating head slider, and a gimbal spring joined to one end of the gimbal spring. A positioner actuator, comprising: a floating head slider support made of a leaf spring-shaped load spring for applying a predetermined load; and a floating head holding mechanism that holds the floating head slider support and slides in contact with the load spring. According to the moving motion of the floating head slider support, the load spring of the floating head slider support comes into contact with the floating head holding mechanism and slides,
A magnetic disk drive comprising a floating head load / unload mechanism for loading or unloading the floating head slider onto or from a magnetic disk medium surface, wherein the floating head holding mechanism and a magnetic disk pindle are fixed to a common base. After the start of rotation of the magnetic disk spindle by turning on the power, the moving motion of the floating head slider support by the positioner actuator is synchronized with the low rotation speed state before reaching the rotation speed for performing normal magnetic recording and reproduction. An operation controller that is set to start, and a setting is made such that a basic rotation frequency of the magnetic disk spindle at the time of starting the movement and the natural frequency of the floating head holding mechanism substantially match. I do.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The magnetic disk drive according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a side view showing an embodiment of a magnetic disk drive according to the present invention, and FIG. 2 is a front view showing the relationship between mechanical elements of the embodiment.

FIGS. 1 and 2 show the structure of a magnetic disk drive having a load / unload mechanism for a floating head called a general ramp load method. A floating head slider support 1 composed of a gimbal spring, a load spring, and a floating head slider is paired and held by a carriage 6.
Rotate in a plane parallel to the surface of. When the floating head slider support is sufficiently moved to the outer peripheral track of the magnetic disk medium 3, the floating head slider support 1 is lifted while contacting and sliding with the floating head holding mechanism 2, thereby unloading the floating head slider. The operation is performed, and the loading operation is performed in the reverse process. FIG. 2 shows an unloaded state. In this case, the floating head slider support 1 and the floating head holding mechanism 2 are in contact with each other. This unloading state is a general form during stoppage of the apparatus, and the magnetic disk spindle 4 stops rotating.

As shown in FIG. 1, a magnetic disk spindle 4 on which a magnetic disk medium 3 is mounted is fixed on a base 5, and a floating head holding mechanism 2 for holding a floating head slider support 1 during unloading. Are similarly fixed on the base 5. Next, the positioner actuator 8 and the magnetic disk spindle 4 are mutually connected to the synchronous controller 10 by the electric connection means 9. This configuration is omitted in FIG. 2 for simplicity. The synchronization controller 10 has a function of reading the rotation speed of the magnetic disk spindle 4 via the electric connection means 9, and when the rotation speed of the magnetic disk spindle 4 reaches a certain value, via the electric connection means 9. Then, a movement command is given to the positioner actuator 8, thereby causing the floating head slider support 1 to perform a turning movement, that is, a function to start a so-called loading operation.

FIG. 3 is a perspective view for explaining details of the floating head holding mechanism 2 of the present embodiment.

The floating head slider support 1 is mounted on the ramp cam 15 by a loading / unloading operation.
A ramp 12 (not shown) is provided for starting or ending the contact sliding, and is provided to a floating head slider support holding surface 11 for holding the floating head slider support 1 while the magnetic disk drive is stopped. It is connected with. This lamp cam 15 has a pair of thin plate-shaped support beams 1.
4 are connected to each other, and one end thereof is further integrated with the base fixing portion 13. The base fixing portion 13 is fixed to the base 5 (not shown).

Here, by appropriately setting the rigidity of the support beam 14 and the mass of the ramp cam 15, the floating head holding mechanism 2 constitutes a vibration system for vibrating the ramp cam 15 in the X direction in the drawing. The present invention is characterized in that the fundamental vibration frequency of the floating head holding mechanism 2 is set slightly lower than the fundamental rotation frequency of the magnetic disk spindle 4 (not shown) in a steady state.

FIG. 4 is a frequency response diagram for explaining the relationship between the fundamental vibration frequency in the X direction and the rotation frequency of the magnetic disk spindle 4 of the floating head holding mechanism of this embodiment set as described above, as shown in FIG. is there.

Here, the frequency on the horizontal axis shown in FIG. 4 indicates a basic rotation frequency synchronized with the rotation speed of the magnetic disk spindle, for example, 60 Hz for a spindle having a steady rotation of 3600 rpm. Further, P1 is the fundamental frequency of the magnetic disk spindle in the steady state in this embodiment, and P0 is the rotation frequency of the magnetic disk spindle 4 at the point where the loading operation is started by the synchronization controller 10 shown in FIG. Since the magnetic disk spindle 4 is also stopped while the apparatus is stopped, the frequency increases with the start of rotation, and passes through P0 to P1. Here, assuming that the loading operation is started at the frequency P0, the resonance characteristic of the floating head holding mechanism 2 at that point resonates as shown in FIG. This is because the base 5 is forcibly excited by a slight rotational imbalance in the magnetic disk spindle, and is transmitted to the floating head holding mechanism 2 as an exciting force to resonate.

At this time, since the floating head slider support holding surface included in the floating head holding mechanism 2 also vibrates in the X direction, a slight slip occurs between the floating head slider support and the floating head slider support 1 that abuts on the surface. become. Therefore, when the loading operation is started by a command from the synchronous controller 10 in this state, only a dynamic frictional force acts between the two at the moment of the operation start, so that a large frictional force exceeding the static frictional force is applied. No torque is required of the positioner actuator 8. This means that the loading operation can be smoothly excited with a relatively small current, and therefore does not require a large current at the starting point, which is a problem in the ordinary ramp load method as described above, and therefore, In addition, it is possible to reduce the danger of contact of the head medium, which occurs during the operation, and to realize the operation of the positioner actuator 8 within the starting current limit.

The resonance characteristic of the floating head holding mechanism, as observed at P1 in FIG. 4, shows a follow-up characteristic in a steady rotation state, so that the floating head holding mechanism becomes fatigued by resonance in a normal use state of the apparatus. There is no reliability issue.

In this embodiment, for simplicity of explanation, an apparatus having a single magnetic disk medium has been described as an example. However, it is needless to say that the present invention can be realized as an apparatus having a plurality of disks.

[0025]

In the magnetic disk drive of the present invention, the floating head holding mechanism constituting the load / unload mechanism is resonated by the rotational excitation force of the magnetic disk spindle, and at the same time, the loading is synchronized by the positioner actuator and the magnetic disk spindle. By setting the start of the operation, it is possible to reduce a large current torque required at the time of starting the loading operation in the magnetic disk device having the conventional load / unload mechanism, thereby reducing the head caused by the sudden movement of the magnetic head. It has the advantage that it avoids the danger of contacting the medium and at the same time can be started with a small current that satisfies the current limit.

As a result, in combination with the load / unload mechanism, the probability of occurrence of a head crash is greatly reduced, and a highly reliable magnetic disk drive can be realized.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of a magnetic disk drive according to the present invention.

FIG. 2 is a front view illustrating the embodiment.

FIG. 3 is a perspective view illustrating details of a floating head holding mechanism constituting the embodiment.

FIG. 4 is a frequency response diagram illustrating vibration characteristics of the floating head holding mechanism of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Floating head slider support 2 Floating head holding mechanism 3 Magnetic disk medium 4 Magnetic disk spindle 5 Base 6 Carriage 7 Rotary shaft 8 Positioner actuator 9 Electrical connection means 10 Synchronization controller 11 Floating head slider support holding surface 12 Lamp 13 Base Fixing part 14 Support beam 15 Lamp cam

Claims (1)

(57) [Scope of request for utility model registration] A gimbal spring comprising a floating head slider, a tongue-shaped leaf spring supporting the floating head slider, and the gimbal spring joined to one end thereof;
A floating head slider support made of a leaf spring-shaped load spring for applying a predetermined load to the floating head slider; and a floating head holding mechanism that holds the floating head slider support and slides in contact with the load spring. Then, the load spring of the floating head slider support is brought into contact with the floating head holding mechanism and slid by the movement of the floating head slider support by the movement actuator to load the floating head slider onto the surface of the magnetic disk medium. Alternatively, a magnetic disk drive including a floating head load / unload mechanism for unloading, wherein the floating head holding mechanism and the magnetic disk pindle are fixed to a common base, wherein rotation of the magnetic disk spindle by turning on power is provided. Normal magnet after start An operation controller configured to start the movement of the floating head slider support by the positioner actuator in synchronization with a low rotation speed state before the rotation speed at which the magnetic recording and reproduction is performed, and A magnetic disk drive wherein the basic rotational frequency of the magnetic disk spindle at the start and the natural frequency of the floating head holding mechanism are set to substantially match.