JPS6131435Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a magnetic disk device in which the air pressure difference in the closed structure of the closed magnetic disk device can be adjusted in a completely sealed state.

A sealed magnetic disk device is a magnetic disk device that stores the magnetic disk and magnetic head inside a sealed structure, prevents the intrusion of external dust, and allows high-density information storage in a highly clean environment. Widely used as a disk device. The sealed structure used here needs to have the function of keeping the internal and external air pressures in balance, in addition to keeping dust out from the outside.

A pressure difference with the outside occurs due to the expansion and contraction of air due to the rise and fall of temperature inside the sealed structure, the internal pressure distribution caused by the rotating magnetic disk, and changes in atmospheric pressure due to weather changes. When this pressure difference becomes large, problems such as impairing the stable floating of the magnetic head and inviting lubricating oil from the magnetic disk rotation drive mechanism (spindle) occur. For this reason, this type of magnetic disk device is provided with an air pressure difference adjustment mechanism for eliminating the air pressure difference between the inside and outside of the sealed structure and maintaining equilibrium.

The above-mentioned pressure difference adjusting mechanism that has been used in the past has been such that the inside and the outside are communicated by a through passage passing through the side wall of the sealed structure, and an air filter is installed in the through passage. This type of pressure difference adjustment mechanism using an air filter allows moisture to flow in along with air from the outside through the air filter, so there is a high risk of the magnetic head falling due to an increase in humidity inside the sealed structure. Katta.

In this invention, in order to eliminate the above-mentioned drawbacks, the air pressure difference adjustment mechanism is made into a sealed structure so that the air pressure difference can be adjusted. This invention will be explained in detail below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of this invention, in which 1 is a sealed structure, 2 is a spindle, 3 is a bearing of the spindle 2 attached to the sealed structure 1, and 4 is a bearing attached to the spindle 2. a magnetic disk, 5 a magnetic head, 6 a magnetic head moving mechanism for moving the magnetic head 5 to a target track, 7
is a motor; 8 is a belt that transmits the rotation of the motor 7 to the spindle 2; 9 is a pressure difference adjustment mechanism; 10
An internal pipe connects the inside of the sealed structure 1 and the inside of the pressure difference adjustment mechanism 9, and one end thereof is opened inside the pressure difference adjustment mechanism, and the other end is opened in the vicinity of the spindle 2. Reference numeral 11 indicates an external pipe that communicates the inside of the pressure difference adjustment mechanism 9 with the outside air. Note that a part of the spindle 2, the magnetic disk 4, the magnetic head 5, the magnetic head moving mechanism 6, and the internal pipe 10
A part of it is housed inside the closed structure 1.

In the above structure, when the motor 7 rotates and the spindle 2 rotates via the belt 8, the air pressure inside the sealed structure 1 becomes uneven.
In particular, the air pressure near the spindle 2 decreases, making it easier for air containing lubricating oil to flow into the sealed structure 1 from the outside air side of the spindle 2 via the bearing 3 of the spindle 2. In order to prevent this, a pressure difference adjustment mechanism 9 is provided, and the internal pipe 10 is extended to the vicinity of the spindle 2 to make this part almost equal to the outside pressure. Outside air is introduced into the pressure difference adjustment mechanism 9 through the external pipe 1.
Do it in 1.

Next, the air pressure difference adjustment mechanism 9 will be explained in more detail.

Figures 2a and 2b are diagrams showing details of the air pressure difference adjusting mechanism 9 used in this invention, and 12 indicates a movable wall with a bellows structure that maintains a sealed state and moves based on the air pressure difference.

Figure 2a shows a state in which the spindle 2 is stopped;
In other words, the movable wall 12 is in an inactive state, and the movable wall 12 is greatly bulging. At this time, the internal air pressure of the sealed structure 1 is uniform.

Figure 2b shows a state in which the spindle 2 is rotating;
That is, it shows the operating state of the movable wall 12, and as explained in FIG. 1, the internal pressure of the sealed structure 1 becomes non-uniform, and the pressure at the tip of the internal pipe 10 decreases. Therefore, the moving wall 12 contracts as shown in the figure.
Outside air enters the inside of the pressure difference adjustment mechanism 9 from the external pipe 11, and the movement of the movable wall 12 stops when the pressure difference between the inside and outside of the movable wall 12 becomes approximately equal. At this time, the pressure at the tip of the internal pipe 10 becomes approximately equal to the external pressure, and it is possible to prevent air containing lubricating oil from entering through the bearing 3 of the spindle 2. Furthermore, since the movable wall 12 moves in a sealed state, it is also possible to prevent moisture from entering.

In addition, although the above embodiment describes the moving wall 12 having a bellows structure, this invention is not limited to this and may be in the shape of a bag, and it goes without saying that the number of bellows or bags is not limited either. .

As explained above, the magnetic disk device according to this invention is equipped with a movable wall that maintains the sealed state as a pressure difference adjustment mechanism of the sealed structure and moves so that the pressure difference inside and outside the sealed structure is equalized. By providing a pressure difference adjustment mechanism and an internal pipe that connects this mechanism to the vicinity of the spindle inside the sealed structure, it is possible to eliminate the pressure difference between the inside and outside of the sealed structure, thereby reducing the pressure inside the sealed structure. This prevents the ingress of moisture, which prevents the internal humidity of the sealed structure from rising and reduces the possibility of condensation. This reduces the risk of the magnetic head falling or damaging the magnetic head and magnetic disk, increasing the reliability of the magnetic disk drive. can improve sex. Furthermore, since an internal pipe is used, there is an advantage that areas where pressure differences are likely to occur can be quickly adjusted.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of this invention, and FIGS. 2a and 2b are schematic sectional views showing details of the air pressure difference adjustment mechanism of FIG. 1. In the figure, 1 is a sealed structure, 2 is a spindle, 3 is a bearing, 4 is a magnetic disk, 5 is a magnetic head, 6 is a magnetic head moving mechanism, 7 is a motor, 8 is a belt,
9 is a pressure difference adjustment mechanism, 10 is an internal pipe, 11 is an external pipe, and 12 is a movable wall. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A sealed magnetic disk device comprising a magnetic disk and a magnetic head that are rotated by a spindle in a sealed structure, which is operated by a pressure difference between the air pressure inside the sealed structure and the outside air to maintain a sealed state. The pressure difference adjusting mechanism includes a moving wall that moves in a direction in which the pressure difference decreases, and an internal pipe that has one end opened inside the pressure difference adjustment mechanism and the other end opened near the spindle. A magnetic disk device characterized by: