JP2000195206A - Magnetic disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a structure of a drop sensor which is effective in avoiding crush between a magnetic head and a magnetic disk by sensing the dropping state of the magnetic disk device. SOLUTION: A drop sensor furnished with a retreating mechanism for causing the magnetic head to set so at from the upper part of the magnetic disk, the drop sensor provided with a conductive flexible beam 1, a conductive weight 2 mounted at a tip of the flexible beam, and a conductive wall 3 freely detachable for the weight is arranged on the magnetic disk device, and this drop sensor is constituted so that the weight 2 separates away from the wall, when the magnetic disk is dropped to become the agravic state from the contact state, such as the flexible beam 1 being deflected by the self-gravity of the weight 2 and the weight brought into contact with the conductive wall 3, then the dropping state of the magnetic disk device is sensed by the drop sensor, thereby the above magnetic head is retreated to the retreating mechanism. It is preferable that the conductive wall of the drop sensor be formed cylindrical body in shape.

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 and, more particularly, to a technique for improving the shock resistance of a shock applied vertically to a magnetic disk surface due to a drop of the magnetic disk drive.

[0002]

2. Description of the Related Art Conventionally, a magnetic disk drive has been provided with a sensor for detecting an impact, and the operation has been stopped when an impact is applied to minimize the damage due to the impact.

[0003] However, in the prior art, there is no function of detecting the drop and retracting the magnetic head outside the magnetic disk so as to avoid contact between the magnetic disk and the magnetic head.
Also, Japanese Patent No. 2682506 (Japanese Unexamined Patent Application Publication No. 8-297817)
As described in the publication, when an impact is applied,
A structure that suppresses the force of the magnetic head hitting the magnetic disk has been adopted.

[0004]

In the prior art,
If the magnetic disk device in operation falls, the impact sensor is activated after the impact is applied after the fall. This sensor operation allows instantaneous reading and writing of signals to the magnetic disk. Avoidance of impacts such as stopping work was able to minimize damage.

However, in order to prevent the magnetic head from hitting the magnetic disk surface due to impact in the direction perpendicular to the magnetic disk surface, the magnetic head is moved out of the magnetic disk after the sensor is activated after the impact is applied. There was no time to perform the moving operation, and damage due to impact could not be avoided.

Accordingly, an object of the present invention is to propose a sensor structure for detecting a drop before an impact is applied.

[0007]

In order to solve the above problems, the present invention mainly employs the following configuration.

A magnetic disk for recording or reproducing information,
A motor for rotating the magnetic disk, a base for fixing the motor, a magnetic head for reading and writing to the magnetic disk, a carriage for supporting the magnetic head, and moving the magnetic head to an arbitrary position on the magnetic disk A magnetic disk device comprising: a coil mounted on the carriage for causing the magnetic head to form a magnetic circuit so as to sandwich the coil; and a retracting mechanism for retracting the magnetic head from above the magnetic disk. A drop detection sensor having a conductive flexible beam, a conductive weight attached to a tip of the flexible beam, and a conductive wall which can freely contact and separate from the weight. It is installed in a device, and the drop sensor detects that the magnetic disk device is falling, and the magnetic sensor is detected by this detection. Magnetic disk drive for retracting the head to retract mechanism.

Further, in the magnetic disk drive, the conductive wall of the drop sensor is a cylindrical body.

In the magnetic disk drive, two drop detection sensors are provided and attached to the base such that the directions of the flexible beams 1 of the drop detection sensors are orthogonal to each other on the same plane. Magnetic disk unit.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a diagram schematically illustrating a magnetic disk drive according to an embodiment of the present invention, and FIG. 2 is a diagram illustrating a first configuration example of a fall detection sensor. FIG. 3 is a diagram showing a second configuration example of the fall detection sensor, and FIG. 4 is a diagram schematically showing a magnetic disk drive according to another embodiment of the present invention.

Referring to FIG. 1, a magnetic disk drive according to an embodiment of the present invention has at least one magnetic disk 5 for recording information, a motor for rotating the magnetic disk 5, A base 6 for fixing a motor, a magnetic head 7 for reading and writing to the magnetic disk 5, a carriage 8 for supporting the head 7, and the head 7 at an arbitrary position on the magnetic disk 5 A coil 9 attached to the carriage 8 for movement, a voice coil motor 10 forming a magnetic circuit so as to sandwich the coil 9, and the head 7
11 for retracting the disk outside the disk 5
And a drop detection sensor 12 mounted in the base 6
And

In this embodiment, as shown in FIG. 2, a conductive weight 2 is attached to the tip of a conductive flexible beam 1, and the weight 2
The flexible beam 1 bends due to its own weight and comes into contact with the conductive wall 3, so that the contact portion is electrically connected. Then, when the magnetic disk device falls in the vertical direction of the wall 3 from the contact state, the weight becomes the zero-gravity state, the deflection of the flexible beam 1 due to its own weight is eliminated, and the weight 2 separates from the wall 3. At this time, the structure is such that the conduction between the weight 2 and the wall 3 is lost and the fall is sensed.

FIG. 3 shows another example of the structure of the fall detection sensor. The conductive flexible beam 1 in the drop sensor is formed in a cylindrical shape, and the conductive wall 3 is changed from a planar shape to a cylindrical shape. By adopting such a shape, even when the magnetic disk drive is slightly inclined from the reference plane, for example, even when the magnetic disk drive is installed slightly inclined from the horizontal plane, the contact pressure between the weight and the wall changes. Therefore, the conductivity can be maintained in a more stable state. That is, as compared with a sensor in which the cross-sectional shape of the flexible beam is rectangular or the wall has a planar shape, the contact pressure and the conductivity of the fall detection sensor of the present embodiment are stably maintained. .

FIG. 4 shows a magnetic disk drive according to another embodiment of the present invention. By using two drop detection sensors having the structure shown in FIG. 3 (the sensor shown in FIG. 2 can be applied as a matter of course), the bases are arranged such that the directions of the flexible beams 1 are orthogonal to each other on the same plane. By mounting the magnetic disk drive at any angle, stable contact can be maintained even when the magnetic disk drive is tilted at any angle (for example, stable contact can be maintained even when the magnetic disk drive is tilted around the direction of the beam of the drop detection sensor as the central axis). However, when the beam is tilted about the direction perpendicular to the direction of the beam on the same plane as the central axis, there is a slight difficulty in stable contact. Either of the fall detection sensors responds to any inclination of the angle to enable stable contact).

According to another embodiment shown in FIG.
Even if the magnetic disk device falls from any direction, the fall can be detected by one of the fall detection sensors.

As described above, the embodiments of the present invention include those having the following configurations and functions.

A conductive weight is attached to the tip of the conductive flexible beam, and the flexible beam is bent by its own weight to come into contact with the conductive wall, and the contact portion is made conductive. When it falls from the contact state, it becomes a zero-gravity state, the deflection of the flexible beam due to its own weight is lost, and the weight separates from the wall. At this time, there is a structure in which the continuity is lost and the falling is sensed.

A drop sensor having a structure in which a conductive weight is attached to the tip of a conductive flexible beam, the flexible beam flexes due to the weight of the weight and contacts a conductive wall, and the contact portion is conductive. When the magnetic disk device to which the drop sensor is attached falls, the conductive weight at the tip of the conductive flexible beam becomes weightless, causing the flexible beam to bend. Eliminate.

Then, the deflection is eliminated by the restoring force of the flexible beam, and the weight separates from the conductive wall, so that it is possible to sense that the electric conduction is lost and the object is falling (during fall). When the fall is sensed, the data recording / reading operation is interrupted, and the operation of retracting the magnetic head from above the magnetic disk can be performed. Thus, destruction due to contact between the magnetic head and the magnetic disk due to an impact at the time of falling can be avoided.

[0021]

According to the present invention, it is possible to detect a fall with a simple structure of the fall sensor.
By this sensing, the magnetic head can be evacuated from above the magnetic disk, and it is possible to prevent the magnetic head and the magnetic disk from coming into contact with each other due to impact and being destroyed.

[Brief description of the drawings]

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

FIG. 2 is a diagram illustrating a first configuration example of a fall detection sensor.

FIG. 3 is a diagram illustrating a second configuration example of the fall detection sensor.

FIG. 4 is a diagram schematically showing a magnetic disk drive according to another embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 conductive flexible beam 2 conductive weight 3 conductive wall 4 housing 5 magnetic disk 6 base 7 magnetic head 8 carriage 9 coil 10 voice coil motor 11 lamp 12 drop sensor

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Masatoshi Ishikawa 2880 Kozu, Odawara-shi, Kanagawa F-term in the Storage Systems Division, Hitachi, Ltd. (Reference) 5D076 AA01 BB01 CC05 EE01 FF03 GG01 GG20

Claims (4)

[Claims] 1. A magnetic disk for recording or reproducing information, a motor for rotating the magnetic disk, a base for fixing the motor, a magnetic head for reading and writing on the magnetic disk, and a carriage for supporting the magnetic head A coil attached to the carriage for moving the magnetic head to an arbitrary position on a magnetic disk; a voice coil motor that constitutes a magnetic circuit so as to sandwich the coil; A magnetic disk drive having a retracting mechanism for retracting from the disk, comprising: a conductive flexible beam; a conductive weight attached to a tip of the flexible beam; A drop detection sensor having a conductive wall; and installing the drop detection sensor on the magnetic disk device, wherein the magnetic disk device is falling. Sensed by the serial fall detecting sensor, a magnetic disk device characterized by retracting the magnetic head in retracting mechanism by the sensing. 2. The magnetic disk device according to claim 1, wherein the weight of the weight causes the flexible beam to bend, and the magnetic disk falls from a contact state in which the weight contacts a conductive wall to a weightless state. A magnetic disk drive, characterized in that the magnetic disk drive is a fall sensor having a configuration in which the weight separates from the wall when the weight is changed. 3. The magnetic disk drive according to claim 1, wherein the conductive wall of the drop sensor is a cylindrical body. 4. The magnetic disk drive according to claim 1, 2 or 3, wherein two said drop detection sensors are provided, and the directions of the flexible beams 1 of said drop detection sensors are mutually the same on the same plane. A magnetic disk drive mounted on the base so as to be orthogonal to the base.