JP3834505B2 - Magnetic disk unit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mechanism for locking an actuator of a magnetic disk device, and in particular, prevents an actuator, a magnetic head, and a magnetic disk surface as a recording medium in a magnetic disk device from being damaged by an impact during non-operation or transportation. The present invention relates to an actuator lock structure.
[0002]
[Prior art]
The magnetic disk drive is a rotating disk having concentric data tracks containing information, a magnetic head that reads / writes data on each track, and a head carrier for moving and holding the head to any track. An information storage device including a coupled actuator.
[0003]
The actuator has a function of moving at high speed in the radial direction of the disk. For this reason, when transporting or not operating the magnetic disk device, the actuator moves from the retracted position to the data area due to an external impact, and the head sticks on the recording surface of the disk, or the disk is damaged and written. It will cause serious troubles such as destroying information. In order to prevent such an obstacle, the actuator is locked in place.
[0004]
Impact resistance is one of the performances required for a magnetic disk device. Particularly, a magnetic disk device mounted on a notebook computer that is portable and easy to carry has increased the demand for impact resistance. In general, the impact applied from the outside to the magnetic disk device when carrying, carrying, or dropping is short in application time and large in collision acceleration. In addition, the direction of impact is not only applied in one direction, but from all directions, so there is an increasing demand for improving impact resistance independent of direction.
[0005]
A technique related to a lock mechanism proposed as one method for preventing the above-described failure is disclosed in, for example, Japanese Patent Application Laid-Open No. 7-262716. In this conventional technology, when an external impact is applied to rotate the actuator, the lock lever is rotated by the inertia of the impact, and the lock lever engages with the actuator to lock it. The lock lever rotates the same as the actuator. It has a structure that is easy to rotate with a degree of freedom in the axial direction. This prior art has high impact resistance against an impact in the same direction as the movement direction of the actuator, that is, a rotational impact in which the actuator has an angular acceleration.
[0006]
[Problems to be solved by the invention]
However, the position of the center of gravity of the actuator (consisting of a spring member that holds the slider and a member that holds the coil) with respect to an impact from the same surface direction as the disk surface, that is, a translational impact, is applied to the entire magnetic disk device. When it is at the center of rotation, it has a relatively high impact resistance. However, if the center of gravity is away from the center of rotation, the impact resistance decreases.
[0007]
If the position of the center of gravity is far from the center of rotation, the actuator has an angular acceleration even during translational impact, so it is necessary to lock the actuator, but the lock lever has a mass balanced structure with respect to the center of rotation. There arises a problem that it is difficult to rotate against an impact and the actuator cannot be locked.
[0008]
An object of the present invention is to provide a disk device having a lock mechanism that can reliably limit the movement of an actuator against an external impact.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, the present invention mainly adopts the following configuration.
A head slider for recording or reproducing information on a magnetic disk, an actuator for holding the head slider so as to be swingable in the radial direction of the magnetic disk, and the actuator in a retreat area arranged differently from a data area for recording or reproducing information. In a magnetic disk device comprising a locking mechanism for locking,
The lock mechanism includes a displacement member that is displaced in a direction perpendicular to the swinging direction of the actuator, and a lock portion in which an incompressible fluid flows through a minute gap due to the displacement of the displacement member.
[0010]
Further, in the magnetic disk device, the displacement member has a partition plate at a tip, the lock portion has a housing, and the partition is filled with the incompressible fluid when a gap between the housing and the partition plate is filled. The actuator is moved to the data area by pushing an incompressible fluid through the plate in the housing.
[0011]
The magnetic disk device may further include a connecting member connected to the displacement member, the connecting member including a partition plate at a tip, the lock portion including a housing, and a gap between the housing and the partition plate. When the incompressible fluid is filled in, the partition plate is pushed into the incompressible fluid in the housing to move the actuator to the data area.
[0012]
In the magnetic disk device, the displacement member and the connecting member are coupled by a permanent magnet.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
A magnetic disk device according to an embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a diagram showing an overall configuration of a load / unload system including a lock mechanism in a magnetic disk apparatus according to an embodiment of the present invention, and FIG. 2 is a diagram showing a detailed structural example of the lock mechanism according to this embodiment. FIG. 3 is a diagram showing the operating characteristics of the locking mechanism according to this embodiment. FIG. 4 is a diagram showing another detailed structure example of the lock mechanism according to the present embodiment.
[0014]
Here, 1 is a base, 2 is a disk, 3 is an actuator, 4 is a ramp, 5 is a coil, 6 is a rotating shaft, 7 is an outer periphery stopper, 8 is an inner periphery stopper, 9 is a head arm, 10 is a load beam, 11 Is a head slider, 12 is a head tab, 20 is a locking mechanism, 21 is a housing, 22 is an incompressible fluid, 23 is a lever, 24 is a push pin, 25 is a pin, 26 is a partition plate, 27 is a spring, 28 is a permanent magnet , 29 represent axes.
[0015]
1, the load / unload type magnetic disk apparatus according to this embodiment has a disk rotation mechanism, that is, a spindle motor (not shown) fixed to a base 1, a disk 2, a rotary actuator 3, a ramp 4, and a lock mechanism. 20. In general, the rotary actuator 3 is rotated by a voice coil motor (VCM). The rotary actuator 3 is attached to the base 1 by moving the coil 5 attached to the actuator 3 through a fixed magnetic circuit of a magnetic circuit (not shown) made of a magnet attached to the base 1. It rotates around the rotation axis 6.
[0016]
The outer peripheral stopper 7 and the inner peripheral stopper 8 are attached to the base 1 or a fixed portion other than the rotary actuator 3 to limit the movement of the rotary actuator 3. Generally, an elastic body such as rubber is used for the stopper.
[0017]
The rotary actuator 3 is provided with a coil 5 for moving the actuator on one side of the rotary shaft 6 and a highly rigid arm 9 on the opposite side. The arm 9 holds one or more head sliders 11 for reading / writing information from / to the disk via the spring material 10. Further, the spring material 10 is provided with a tab 12 extending beyond the slider 11. As described above, the actuator 3 includes the spring material 10 holding the slider 11 and the arm 9 connected to the spring material and holding the coil. In addition, although there exists a thing of the structure which makes the member holding the coil 5 a coil holder and separates from the arm 9, the actuator as used in this embodiment points out the member which operates a slider.
[0018]
The load / unload lamp 4 is attached to the base 1. FIG. 1 shows an unloaded state, that is, a state where the disk device is not operating, or a state where data is not read or written, and the actuator 3 is retracted to the lamp 4. The tab 12 of the spring material 10 is supported by a lamp, and prevents the slider 11 and the disk 2 from being damaged or sticking due to impact or the like. The actuator 3 has a structure that is always pressed against the stopper 7 when using a permanent magnet or the like, and does not move due to weak impact or vibration. The force is such that when the actuator 3 moves to the data area of the disk 2 when reading / writing data, the actuator 3 can move by passing a current through the coil.
[0019]
FIG. 2 (1) shows details of the lock mechanism 20 according to the embodiment of the present invention. In the lock mechanism 20, a lever 23 and a push pin 24 are rotatably held around the pin 25, and a partition plate 26 is attached to the tip of the pin 25. The partition plate 26 is mounted in the housing 21 and is positioned at a free length position of the spring 27. The housing 21 is filled with an incompressible fluid 22 (which may be a compressible fluid, but an incompressible fluid is more effective), and passes through a gap between the partition plate 26 and the housing 21. It is possible to move left and right within. The lever 23 is held by a shaft 29 so as to be movable. Here, the movement of the fluid 22 may be a through hole provided in the partition plate 26 in addition to the gap.
[0020]
FIG. 2 (2) shows a state after the actuator has gone out to the data area. The spring 27 is compressed by the lever 23 pushed in by the actuator 3, and the actuator becomes movable. After that, the initial state of FIG. 2 (1) is restored by the spring force.
[0021]
(3) of FIG. 2 shows a state immediately after the actuator returns from the data area to the retracted position. Also in this case, the lock is released on the same principle as in the state (2) in FIG. 2, and then the state returns to the state (1) in FIG.
[0022]
The partition plate 26 is moved left and right by the actuator 3 hitting the lever 23. In this case, the relationship between the force for pushing the partition plate 26 by the gap between the partition plate 26 and the housing 21 by using the incompressible fluid 22 and the time required for the partition plate 26 to move to the state shown in FIGS. The relationship is as shown in In other words, the lock mechanism is a mechanism that requires a large amount of force when the pressing time is short, but that can be pushed in with a weak force for a long time. In other words, FIG. 3 shows the operating characteristics of the locking mechanism, which is a characteristic curve showing the relationship between the force required to operate the partition plate 26 and the time required for it, and if the time is short, the partition plate It can be seen that a large force is required to operate, and that a small force is sufficient if time is taken.
[0023]
In general, most of the impact applied to the magnetic disk device (impact when carrying or carrying, or impact when dropping) is 11 ms or less, and falls within the range of region A shown in FIG. Moreover, if the time for the actuator 3 to move to the data area is set sufficiently long with respect to the impact (impact of 11 ms or less), the necessary force is small, and it can enter and exit from the retracted position without any problem in normal use. It becomes possible. Furthermore, by adopting a structure in which a biasing pressing force (locking direction) is applied to the actuator 3 with respect to the outer peripheral stopper 7 using the leakage magnetic flux of a permanent magnet or VCM in this embodiment, the application time is long. Even for impacts with weak force (normally impacts are strong but application time is short, so the locking effect is achieved in the configuration example of FIG. Even) can exert a sufficient locking effect.
[0024]
As described above, the lock mechanism according to this embodiment (the configuration example shown in FIG. 4 to be described later in addition to the configuration example shown in FIG. 2) is not released for a normal impact, for example, an impact of 11 ms or less. The function or the action that does not enter the unlocked state unless the pressing force is continuously applied for a predetermined period of time or longer, for example, 50 ms or longer.
[0025]
The configuration example of the lock mechanism shown in FIG. 4 is a case where the lever 23 and the push pin 24 made of a magnetic material are connected using a permanent magnet 28. According to this configuration example, the end of the lever 23 and the end of the push pin 24 have abutting surfaces, and the permanent magnet 28 provided at the end of the lever 23 is the end of the push pin 24 of magnetic material. Is sucked to bring the end portions into contact with each other. When the actuator 3 moves from the retracted position to the data area, as shown in (2) of FIG. 4, the actuator 3 operates on the same principle as in (2) of FIG. 2, and depends on the flow of the incompressible fluid. A lock mechanism having a so-called time delay, which operates with a time delay, that is, operates by continuing to push for a certain period of time, is configured.
[0026]
On the other hand, when returning from the data area to the retracted position, as shown in (3) of FIG. 4, the time-delayed locking mechanism due to the flow of the incompressible fluid does not operate and the pushing by the permanent magnet 28 is performed. Only the lever 23 rotates by overcoming the attractive force with the end of the pin 24 and can move to the retracted position smoothly and in a short time (the actuator 3 is attractive with the end of the push pin due to the permanent magnet 28). Only the force overcoming this can be done, and the movement is only the time required to rotate only the lever 23). Thereafter, the unlocked lock lever 23 is attracted to the push pin 24 by the force of the permanent magnet 28 and automatically enters the initial state shown in FIG. In the above description, the push pin 24 is a magnetic body. However, the present invention is not limited to this, and a permanent magnet may be provided on the push pin. In short, the end portion of the lever 23 and the end portion of the push pin 24 are important. Any structure may be used as long as they are in contact with each other by magnetic coupling.
[0027]
In addition, since the lock lever 23 has a balanced structure around the rotation shaft 29 (the position of the center of gravity of the lever 23 coincides with the rotation center), the lever 23 can be prevented from rotating due to an impact. Further, by making the rotation direction of the lever 23 and the rotation direction of the actuator different (according to (1) in FIG. 4), the rotation direction of the lever 23 is a plane parallel to the paper surface, and the rotation direction of the actuator 3 is Even when a rotational impact (impact on a surface different from the above-mentioned translational impact) is applied, the lever and the actuator do not move simultaneously, and high reliability can be maintained.
[0028]
Moreover, in this embodiment, it may replace with the structure which consists of the incompressible fluid 22 and the spring 27 which are shown in FIG.2 and FIG.4, and the thing of the structure which has a single elastic characteristic may be sufficient. That is, a single material having the characteristics shown in FIG. 3 may be used.
[0029]
Furthermore, the locking mechanism is not only a magnetic disk device having a load / unload mechanism using a ramp 4, but also a contact start / stop system in which a retreat position is provided on the disk 2 and the head lands on the disk when stopped. The present invention can also be applied to a stop position locking mechanism in the magnetic disk apparatus.
[0030]
As described above, the main feature of the present invention is that the actuator is normally kept in a locked state, and is not unlocked by a short impact such as an impact, but the actuator is moved to the data area in order to read and write data. A lock mechanism that can be unlocked when the lock lever is pressed for a sufficiently long time (for example, 50 ms or more), as in the case of time, so that the actuator can be securely held against external shocks. It is.
[0031]
【The invention's effect】
According to the present invention, a sufficient locking function to the actuator is exhibited against the application of a short-time force such as an impact applied to the magnetic disk device, and no adverse effect is caused to the normal retracting operation of the actuator. A locking mechanism can be provided.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of a load / unload method including a lock mechanism in a magnetic disk device according to an embodiment of the present invention.
FIG. 2 is a diagram showing a detailed structural example of a lock mechanism according to the present embodiment (side view of FIG. 1).
FIG. 3 is a diagram illustrating operating characteristics of a lock mechanism according to the present embodiment.
FIG. 4 is a diagram illustrating another detailed structure example of the lock mechanism according to the present embodiment.
[Explanation of symbols]
1 Base 2 Disc 3 Actuator 4 Lamp 5 Coil 6 Rotating shaft 7 Outer stopper 8 Inner stopper 9 Head arm 10 Load beam 11 Head slider 12 Head tab 20 Lock mechanism 21 Housing 22 Incompressible fluid 23 Lever 24 Push pin 25 Pin 26 Partition Plate 27 Spring 28 Permanent magnet 29 Shaft

Claims (5)

A head slider for recording or reproducing information on a magnetic disk, an actuator for holding the head slider so as to be swingable in the radial direction of the magnetic disk, and the actuator in a retreat area arranged differently from a data area for recording or reproducing information. In a magnetic disk device comprising a locking mechanism for locking,
The lock mechanism includes a displacement member that is displaced in a direction perpendicular to a swinging direction of the actuator, and a lock portion in which an incompressible fluid flows through a minute gap due to the displacement of the displacement member. Disk unit. The magnetic disk device according to claim 1,
The displacement member has a partition plate at a tip, the lock portion has a housing, and when the incompressible fluid is filled in a gap between the housing and the partition plate, the partition plate is incompressible in the housing. A magnetic disk drive , wherein the actuator is moved to the data area by pushing a fluid . The magnetic disk device according to claim 1,
A connecting member connected to the displacement member; the connecting member having a partition plate at a tip; the lock portion having a housing; and a gap between the housing and the partition plate filling the incompressible fluid. When the partition plate is pushed into the housing with an incompressible fluid, the actuator is moved to the data area . The magnetic disk device according to claim 3,
The magnetic disk apparatus, wherein the displacement member and the connecting member are coupled by a permanent magnet . 5. The magnetic disk device according to claim 2 , wherein
The magnetic disk apparatus, wherein the housing and the partition plate are connected by a spring .

Images