JP2564901B2 - Magnetic disk drive - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device for reading data from a surface of a rotating magnetic disk and writing data on the surface of a magnetic disk.

[Prior Art] Generally, in this type of magnetic disk device, a magnetic head is mounted on a rotary type carriage, and the magnetic head is levitated at a minute gap by air pressure generated along with a magnetic disk that rotates at a high speed to read and write magnetic recording. Running. In the carriage of this magnetic disk device, a positioning pattern written in the magnetic disk is read by a servo head and a servo loop is formed for positioning.

Further, this magnetic disk device has been moving in the direction of improving the recording density. As a method of improving the recording density, there are a method of increasing the track bit density and a method of decreasing the track width to increase the track density. There is.
Recently, the track width has been reduced to about 20 μm.

In the conventional magnetic disk device, as shown in FIG. 4, the magnetic disk 1 is rotatably supported on the substrate 3 at both ends of the disk rotation shaft 2 via the spindle hub 4 and the bearings 5a and 5b. The bearing 5a is fixed to the base plate 3, while the bearing 5b is slidably fitted into the bearing support portion 3a of the base plate 3 and is mounted in a direction away from the bearing 5a by the first preload spring 6a for removing backlash. It is energized. On the other hand, the magnetic head 9a corresponding to the magnetic disk 1 is supported by the arm 12a and is rotatably supported by the head rotating shaft 13 via the carriage 15 and the bearings 14a and 14b. The bearing 14a is the bearing support portion 15a of the carriage 15.
The second preload spring 6c that is slidably inserted in the
Is separated from the bearing 14b fixed to the carriage 15, and is urged in the direction opposite to the disc rotating shaft 2. Then, the magnetic head 9a is rotationally driven by the torque generated by the magnetic circuit 17.

The magnetic head 9a is composed of a servo head 8 used for positioning and a data head 7 for reading and writing data. Correspondingly, the arm 12a has a servo arm 11 and a data arm 10.

[Problems to be Solved by the Invention] By the way, the spread of computers has widened the range of the installation environment temperature, and therefore, a large difference may occur in the environment temperature during data writing and data reading. In such a case, the data head 7 is relatively displaced from the track positioned by the servo head 8 due to the temperature expansion of each part of the apparatus, which is one of the major causes of off-track and unreadable information. There was a problem.

The reason is that, in the conventional magnetic disk device, when the environmental temperature rises, the magnetic disk 1 becomes a spindle hub.
4, Bearing 5a on the fixed side due to thermal expansion of material such as magnetic disk 1
With reference to, the first preload spring 6a moves in the direction of arrow A according to the biasing force of the spring. On the other hand, the magnetic head 9a includes an arm 12a and a carriage.
Due to thermal expansion of the material such as 15, the bearing 14b on the fixed side moves in the direction of arrow B according to the urging force of the second preload spring 6c.
That is, the relative heights of the magnetic disk 1 and the magnetic head 9a fluctuate greatly due to temperature changes. As a result, as shown in FIG. 5, the head gimbal 18a attached to the magnetic head 9a is largely tilted, and the magnetic head 9a moves to a position different from that before the temperature change.

Therefore, the technical problem of the present invention is to eliminate the change in relative height between the magnetic disk and the magnetic head even when each part is thermally expanded.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a rotation including a disk rotation shaft that supports a magnetic disk and a first preload spring that axially urges the disk rotation shaft. A magnetic disk drive having a mechanism, a head rotation shaft that supports a magnetic head that is provided corresponding to the magnetic disk, and a rotary carriage that includes a second preload spring that axially urges the head rotation shaft. In the above, the end portions on the same side of the disk rotation shaft and the head rotation shaft are fixed ends, and the first preload spring and the second preload spring are biased in the same direction with respect to the fixed end. It is configured as a spring, and the urging direction of the disk rotation shaft and the urging direction of the head rotation shaft are the same.

[Embodiment] A magnetic disk device according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings. This magnetic disk device includes a rotating mechanism and a rotary type carriage.

FIG. 1 shows a magnetic disk device according to the first embodiment. The rotating mechanism of this magnetic disk device includes a spindle hub 4 that supports the magnetic disk 1.
This spindle hub is fixed to the disc rotating shaft 2, and the disc rotating shaft 2 has bearings 5 mounted on the substrate 3 at both ends thereof.
It is rotatably supported via a and 5b. The bearing 5a is fixed to the base plate 3, while the bearing 5b is slidably fitted into the bearing support part 3a of the base plate 3 and is separated from the bearing 5a by the first preload spring 6a loaded in the bearing support part 3a. It is biased in the separating direction.

Further, the rotary type carriage is provided with a magnetic head 9a provided corresponding to the magnetic disk 1. The magnetic head 9a is supported by an arm 12a fixed to a carriage 15, and the carriage 15 has bearings 14a, 14 on a head rotation shaft 13.
It is rotatably supported via b. The bearing 14a is fixed to the carriage 15, while the bearing 14b is fixed to the carriage 15.
Is slidably inserted in the bearing support portion 15a of the disk, and is separated from the bearing 14a by a second tension preload spring 6b provided on the outside of the bearing 14b. It is energized.

Incidentally, as described above, the magnetic head 9a includes the servo head 8 and the data head 7, and correspondingly, the arm
12a includes a servo arm 11 and a data arm 10.

Therefore, according to the magnetic disk device of the first embodiment, when the temperature of the magnetic disk device rises, the magnetic disk 1 is fixed on the fixed side due to the thermal expansion of the material such as the spindle hub 4 and the magnetic disk 1 as described above. It moves in the direction of arrow A according to the urging force of the first preload spring 6a with reference to the bearing 5a. On the other hand, the magnetic head 9a also moves according to the urging force of the second preload spring 6b with the bearing 14a on the fixed side as a reference due to the remaining amount of the arm 12a, the carriage 15, and the like. In this case, the bearing 14b, which is loaded with preload, urges the head rotating shaft 13 in the same direction as the disk rotating shaft 2 of the magnetic disk rotating mechanism with respect to its axial direction, so that the magnetic head 9a moves. Moves in the same direction as arrow A. Therefore, as a result, the relative heights of the magnetic disk 1 and the magnetic head 9a hardly change even if the temperature changes, and the off-track becomes extremely small immediately, and the problem that information cannot be read is solved. It

FIGS. 2A and 2B show preload spring load positions of the bearings of the rotation mechanism portion and the carriage portion in the magnetic disk device according to the second embodiment. This is the first preload spring
6a is a compression spring and is arranged inside the bearing 5b, while the second preload spring 6b is also a compression spring and is arranged inside the bearing 14b. Therefore, as in the first embodiment, the disk rotary shaft 2 and the head rotary shaft 13 are biased in the same direction,
The same action and effect as described above are obtained.

FIGS. 3 (a) and 3 (b) show the preload spring load positions of the bearings of the rotation mechanism portion and the carriage portion in the magnetic disk device according to the third embodiment. This is bearing 5a and bearing
14a is slidable, the bearing 5a is biased by a first preload spring 6e made of a compression spring arranged inside, and the bearing 14a is biased by a second preload spring 6f made of a tension spring arranged outside. The disk rotation shaft 2 and the head rotation shaft 13 are biased in the same direction.

[Effects of the Invention] As described above, according to the present invention, the end portions on the same side of the disk rotation shaft and the head rotation shaft are fixed ends, and the first preload spring and the second preload spring are fixed. Even if the temperature of the magnetic disk device changes, the springs are biased in the same direction with respect to the end, and the biasing direction of the disk rotation shaft and the biasing direction of the head rotation shaft are in the same direction.
Since each part is displaced in the same direction, the magnetic disk and the magnetic head are also displaced in the same direction, and the relative height change between the magnetic disk and the magnetic head hardly occurs. As a result, the off-track can be made extremely small, and there is an effect that information can be surely read.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a magnetic disk device according to a first embodiment of the present invention, FIGS. 2 (a), 2 (b) and 3 (a),
(B) is a schematic view showing the preload spring load position of the bearings of the rotation mechanism part and the carriage part in the second and third embodiments of the present invention, and FIG. 4 is a longitudinal sectional view of a conventional magnetic disk device, 5
FIG. 1 is a diagram showing a relative height change between a magnetic disk and a magnetic head when there is a temperature change in a conventional magnetic disk device, and an off-track diagram of the magnetic head caused by the change. 1: Magnetic disk 2: Disk rotation axis 3: Substrate 4: Spindle hub 5a, 5b: Bearing 6a, 6b: First preload spring 6b, 6c, 6d, 6f: Second preload spring 7: Data head 8: Servo Head 9a: Magnetic head 9b: Magnetic head after temperature change 10: Data arm 11: Servo arm 12a: Arm 12b: Magnetic head after temperature change 13: Head rotation shafts 14a, 14b: Bearing 15: Carriage 16: Housing 17: Magnetic circuit 18a: Head gimbal 18b: Head gimbal after temperature change

Claims (1)

(57) [Claims] 1. A rotating mechanism comprising a disk rotating shaft for supporting a magnetic disk and a first preload spring for axially urging the disk rotating shaft, and a magnetic head provided corresponding to the magnetic disk. In a magnetic disk drive having a head rotation shaft and a rotary type carriage having a second preload spring for urging the head rotation shaft in the axial direction, the disk rotation shaft and the head rotation shaft on the same side of each other. The end portion is a fixed end, and the first preload spring and the second preload spring serve as springs for urging the first preload spring and the second preload spring in the same direction with respect to the fixed end. A magnetic disk device, wherein the urging direction of the rotating shaft is the same direction.