JPH03252985A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To avoid the degradation of assembling precision of members in a head disk assembly by providing a desiccating agent housing means, where the opening area of an air hole is changed in accordance with the change of the relative humidity of internal air, in a base plate. CONSTITUTION:A humidity detector 57 detects the relative humidity of internal air of a base plate and converts it to an electric signal and outputs the electric signal to a controller 58. When the relative humidity of internal air quickly rises, a disk 56 is rotated to extend the opening area of an air hole 52 and internal air is quickly dehumidified by a desiccating agent 51. When the relative humidity of internal air is reduced too much, the disk 56 is rotated to narrow the opening area of the air hole 52 or completely close the air hole 52 and the reduction of the relative humidity is prevented. Thus, the degradation of the assembling precision of members in the head disk assembly due to the overdrying of the internal air is avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention is applied to head disk assembly.
The present invention relates to a magnetic disk device having a head disk assembly that has an improved method of dehumidifying the air inside a base plate that contains a magnetic disk, a magnetic head, etc.

(Prior art) Conventionally, this type of magnetic disk device has a base play 1.
In order to dehumidify the internal air of the base plate, a desiccant storage case is provided inside the base plate for storing the desiccant and having a vent for the internal air to ventilate.

FIG. 3 shows a configuration diagram of a head disk assembly of a conventional magnetic disk device. 1 is a magnetic disk, 2 is a disk rotation for rotating the magnetic disk 1, Rtf4.3 is a magnetic head, and 4 is positioning of the magnetic head 3. 5 is a desiccant storage case, 6 is a magnetic disk 1. Disc rotation 81 horizontal 2. Magnetic head 3. A base plate 7 includes a head positioning mechanism 4 and a desiccant storage case 5, and is a breathing filter provided on the wall of the base plate 6. FIG. 3 shows the inside of the base plate 6 in cross section. Further, 51 is a desiccant for dehumidifying the internal air of the base plate 6, 52 is a vent hole for ventilation of the internal air, and 53 is a ventilation filter.

The base plate 6 has a magnetic disk 1. Disk rotation mechanism 2. Magnetic head 3. The head positioning mechanism 4 and the desiccant storage case 5 are enclosed to seal the air inside, but a breathing filter 7 is used to prevent sudden pressure changes inside.
Circulation with outside air is carried out through. The magnetic disk 1 is rotated at high speed by the disk rotation mechanism 2.
The magnetic head 3 is floated in a minute gap by the air flow generated by this high-speed rotation, and the head positioning mechanism 4 positions the magnetic head 3 to perform magnetic recording and reproduction. When the relative humidity of the air inside the base plate 6 becomes high, the magnetic disk 1 and the magnetic head 3 will attract each other, causing damage to the magnetic disk 1 and the magnetic head 3. To prevent this, the internal air is dehumidified using the desiccant 51. and keep it at low humidity.

The desiccant 51 is housed in a desiccant storage case 5, and internal air is vented to the desiccant 51 through a vent 52 and a ventilation filter 53.

By the above means, the air inside the base plate 6 is dehumidified and kept at a low humidity.

(Problem to be Solved by the Invention) However, in the conventional magnetic disk drive, if the opening area of the vent 52 of the desiccant storage case 5 is too small, it takes too long for dehumidification to reach a predetermined relative humidity. If it becomes difficult to maintain the humidity, the magnetic disk 1 and the magnetic head 3 will stick together due to high humidity, damaging the magnetic disk 1 and the magnetic head 3, and if the opening area of the vent 52 is too large, the relative humidity will be lower than the specified relative humidity. There is a disadvantage that the humidity becomes too low, causing distortion in the members inside the head disk assembly and deteriorating the assembly accuracy of the members.

In order to solve the above-mentioned problems, it is an object of the present invention to provide a magnetic disk that includes a desiccant storage means inside a base plate in which the opening area of the vent changes in response to changes in the relative humidity of the air inside the head plate. The goal is to provide equipment.

(Means for Solving the Problems) In order to achieve the above object, the present invention has the following means configuration.

That is, the magnetic disk device of the present invention has a magnetic disk drive assembly including a head disk assembly including at least a magnetic disk, a disk rotation mechanism, a magnetic head, and a head positioning mechanism, by a base plate having a breathing filter on the wall surface. The apparatus includes a desiccant for dehumidifying the internal air of the base plate, and has a vent hole for the internal air to ventilate, and the apparatus includes a desiccant for dehumidifying the internal air of the base plate, and has a vent hole for the internal air to ventilate, and is configured to act in response to a change in the relative humidity of the internal air. The magnetic disk device is characterized in that the base plate includes a desiccant storage means in which the opening area of the vent hole changes.

(Function) The function of the magnetic disk device of the present invention configured as described above will be explained.

The base plate includes at least a magnetic disk, a disk rotation mechanism, a magnetic head, a head positioning mechanism, and a desiccant storage means. The air inside the base plate is sealed, but in order to avoid sudden pressure changes inside the base plate, it is communicated with the outside air through a breathing filter provided on the wall of the base plate. A magnetic disk is rotated at high speed by a disk rotation mechanism, a magnetic head is floated in a minute gap by an air flow generated by this high speed rotation, and the magnetic head is positioned by a head positioning mechanism to perform magnetic recording and reproduction.

The internal air of the base plate is dehumidified by the desiccant stored in the desiccant storage means, but the opening area of the vent through which the internal air vents changes in response to changes in the relative humidity of the internal air. Maintain low humidity at a given relative humidity. In other words, as the relative humidity of the internal air increases, the opening area of the vent increases, and as the relative humidity decreases, the opening area of the vent decreases, reducing the internal air to a predetermined relative humidity. Hold.

(Embodiment) Next, an embodiment of the magnetic disk device of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a head disk assembly of a magnetic disk device according to an embodiment of the present invention. 54 is desiccant storage case 5
55 is a rotating shaft of the step motor 54 that protrudes from the inside of the desiccant storage case 5 to the outside, and 56 is attached to the rotating shaft 55 in close contact with the outer wall surface of the desiccant storage case 5. 57 is a humidity detector that detects the relative humidity of the internal air; 56 is a controller that receives an electric signal from the humidity detector 57 and controls the operation of the step motor 54;
9 is a wiring between the controller 58 and the step motor 54. Components given other numbers in the figure are similar to those given the same numbers in the conventional example of FIG. Therefore, in the following, detailed explanations regarding these components similar to those of the conventional example will be omitted. Moreover, FIG. 1 is a diagram showing the inside of the base plate 6 in cross section.

The following describes the operation of dehumidifying the air inside the base plate 6 and maintaining it at a predetermined low relative humidity with respect to the embodiment of the present invention shown in FIG.

The humidity detector 57 detects the relative humidity of the air inside the base plate 6, converts it into an electrical signal, and outputs the electrical signal to the controller 58. The controller 58 receives the electrical signal from the humidity detector 57, generates a control signal based on the electrical signal, and sends the control signal to the step motor 54 through a wiring 59 to control the operation of the step motor 54. The rotation of the rotary shaft 55 of the step motor 54 causes the disc 56 attached to the rotary shaft 55 to rotate.The zero disc 56 is in close contact with the outer wall surface of the desiccant storage case 5, and its positional relationship with the vent 52 is The fan-shaped cutout portion does not cover the ventilation port 52,
The portions other than the fan-shaped cutout portions are positioned so as to shield the ventilation port 52. As the disc 56 rotates, the relative positional relationship between the fan-shaped cutout portion of the disc 56 and the vent 52 changes, and the area that the disc 56 covers the vent 52 changes. That is, the opening area of the vent 52 changes.

FIG. 2 is a configuration diagram of the desiccant storage means according to the embodiment of the present invention, showing a case in which the disk 56 covers half of the vent 52 and the opening area of the vent 52 is half of the total opening area. There is.

When the relative humidity of the air inside the base plate 6 suddenly increases, the disc 56 is rotated so as to increase the opening area of the vent 52, and the desiccant 51 quickly dehumidifies the inside air. If the relative humidity of the air drops too much, the disk 56 is installed to reduce the opening area of the vent 52 or to completely block the vent 52.
Rotate to prevent relative humidity from dropping.

By the above-described operation, the air inside the base plate 6 is maintained at a predetermined low relative humidity.

In the embodiment of the present invention described above, the desiccant storage case 5, the desiccant 51, the ventilation port 52, the ventilation filter 53, the step motor 54. The desiccant storage means includes the rotating shaft 55, the disk 56, the humidity detector 57, the controller 5δ, and the wiring 59, but this is just one example and is not particularly limited to the above configuration. It's not something you can do.

(Effects of the Invention) As explained above, the magnetic disk device of the present invention stores a desiccant for dehumidifying the air inside the base plate and has a vent for ventilating the inside air. A desiccant storage means is provided inside the base plate, and the opening area of the vent changes in response to changes in the relative humidity of the air.

Therefore, by changing the opening area of the vent according to the relative humidity of the internal air, the amount of ventilation of the internal air can be adjusted.
Since the internal air can be maintained at a predetermined relative humidity, it has the effect of avoiding adhesion between the magnetic disk and the magnetic head due to the internal air being too humid, and also preventing head disk assembly due to the internal air being too dry. This has the effect of avoiding deterioration in the accuracy of assembling internal members.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a head disk assembly of a magnetic disk drive according to an embodiment of the present invention, FIG. 2 is a block diagram of a desiccant storage means of an embodiment of the present invention, and FIG. 3 is a block diagram of a head disk assembly of a conventional magnetic disk drive. FIG. 1... Magnetic disk, 2... Side of disk rotating machine, 3... Magnetic head, 4...
... Head positioning mechanism, 5 ... Desiccant storage case, 6 ... Base plate, 7.
... Breathing filter, 51 ... Desiccant, 52 ... Ventilation port, 53 ... Ventilation filter, 54 ... Step motor,
55... Rotating shaft 56... Disc, 57
...humidity detector, 58 ...controller,
59...Wiring.

Claims (1)

[Claims] A base plate with a breathing filter on the wall allows
In a magnetic disk drive having a head disk assembly including at least a magnetic disk, a disk rotation mechanism, a magnetic head, and a head positioning mechanism, a desiccant for dehumidifying the air inside the base plate is stored, and The desiccant storage means is provided inside the base plate, the desiccant storage means having a vent through which the internal air is ventilated, and the opening area of the vent changing in response to a change in the relative humidity of the internal air. magnetic disk device.