JP2530596Y2 - Spindle bearings for disk devices - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application field] The present invention relates to a disk rotation drive device of a disk drive device.

[Conventional technology]

The bearing of the spindle of the direct drive motor of the conventional disk drive has the structure shown in FIG. 4, and FIG. 4 is a sectional view of the conventional spindle motor.

At one end of the spindle 1, a rotor magnet 2 for rotating the spindle 1 and a rotor 3 are fixed.
At the other end of the spindle 1 is a plastic jacket 4
A hub base 7 for suction-rotating and driving a chucking hub 6 provided on a disk-shaped flexible magnetic medium 5 (hereinafter, referred to as a flexible disk) accommodated in the disk base is fixed. The spindle 1 is supported by two ball bearings 8, and the radial play and the play in the thrust direction of the bearing 8 are removed by a preload spring 9. The upper end of the spindle 1 has a structure that contacts the jacket 4 and pushes up the jacket 4 to secure a rotating space for the flexible disk 5.

[Problems to be solved by the invention]

However, according to the above-described prior art, the radial runout of the spindle 1 and the play in the thrust direction can be manufactured with high accuracy, but the two ball bearings 8 and the preload springs 9 can be manufactured.
However, it is very expensive, and also requires a housing 10 for holding the ball bearing 8 with high accuracy, which causes problems such as a decrease in assemblability and a decrease in yield.

Accordingly, the present invention has been made to solve such a problem, and an object of the present invention is to reduce the protrusion to the lower surface of the disk device and reduce the thickness of the entire disk drive device.

[Means for solving the problem]

The disk rotation drive device of the present invention includes a spindle for guiding the center of a disk hub provided at the center of the disk,
A disk rotation drive device comprising: a spindle bearing that supports the spindle; and a hub base that receives the disk hub on a disk side with respect to the spindle bearing of the spindle; an end of the spindle opposite to the hub base. A female screw portion is provided in the portion, and a screw that engages with the female screw portion and regulates the amount of movement of the spindle in the thrust direction is arranged,
A recess for accommodating the screw is formed at an end of the spindle bearing opposite to the hub base.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of a spindle motor according to a first embodiment of the present invention.

As in FIG. 4, one end of the spindle 21 has a spindle
Rotor magnet 22 for rotating 21 and rotor
23 is fixed, and at the other end of the spindle 21, a hub base 24 for adsorbingly driving a chucking hub 6 provided on a disc-shaped flexible disk 5 housed in a plastic jacket 4 is fixed. is there.

The spindle 21 is supported in the radial direction by two metal bearings 25.

In this configuration, the rotor magnet 22 is moved by an arrow between
A suction force is generated in the direction of 28, that is, upward. On the other hand, the upper end of the spindle 21 comes into contact with the plastic jacket 4 and receives pressure in the direction indicated by the arrow 29 in FIG.

In the motor having the structure as shown in FIG. 1 having the air gap in the radial direction in the first embodiment of the present invention, the suction force in the thrust direction (the direction of arrow 28 in the figure) is not large.
It was about 100g in actual measurement. On the other hand, the force received by the spindle 21 from the jacket 4 (arrow 29 in the figure) has a variation of about 0 to 300 g in actual measurement.
21, the hub stand 24, the rotor 23, and the rotor magnet 22 are not fixed in the thrust direction, and the gap with the metal bearing 25 is 3
It will move by 0,30a. However, since thrust friction with the metal bearing 25 becomes a problem due to the movement in the thrust direction for the above-described reason, thrust washers 31, 31a made of plastic are inserted. In this structure, when the amount of movement in the thrust direction was set to 0.15 mm or less, good contact between the flexible disk 5 and the magnetic heads 32 and 32a could be ensured. Further, by adopting such a structure, even in a direct drive motor having an air gap in a radial direction having a weak attraction force, the bearing can be metallized, and the cost can be greatly reduced.

Since the attraction force in the thrust direction is weak, the wear of the thrust washers 31, 31a did not cause any problem, and a long life could be maintained.

FIG. 2 shows a second embodiment of the present invention, and FIG. 2 is a sectional view of a spindle motor according to a second embodiment of the present invention.

In FIG. 2, the spindle 21 is supported in the radial direction by a metal bearing 25 which also serves as a holding member for the stator 26. Also, the thrust direction receiving of the spindle 21 is
As in FIG. 1, the structure is received by thrust washers 31, 31a.

With this configuration, the structural members of the bearing and the motor can be integrated, so that the bearing accuracy can be improved as compared with the case where two separate metal bearings are used, and the cost can be reduced by reducing the number of parts. Can do things.

It goes without saying that other effects are the same as those in the case of FIG.

FIG. 3 shows an embodiment of the disk rotation driving device according to the present invention, and FIG. 3 is a sectional view of the disk rotation driving device according to the present invention.

In FIG. 3, a rotor magnet 22 for rotating the spindle 21 and a rotor 23 are fixed to one end of the spindle 21 via a hub stand 24 for driving the chucking hub 6 by suction rotation. At the other end of the spindle 21, a thrust stopper 33 is provided so that the spindle 21 does not protrude from the metal bearing 25 due to impact, vibration, or the like.
Are fixed by screws 34. Stator 26 is fixed to metal bearing 25, and metal bearing 25 is fixed to motor frame 27 by caulking.

In the above configuration, the axial positional relationship between the stator 26 and the rotor magnet 23 is configured to a required positional relationship, so that the thrust suction force (in the direction of the arrow 28 in the figure) by the rotor magnet 23 and the jacket 4 spindle
The combined force of the force (arrow 29 in the figure) received by 21 can be configured to always act in the downward direction in the figure, and the gap 30 shown in FIG. 1 can be set to zero. On the other hand, in FIG. 3, the gap 30a becomes large, but the spindle 21 moves in the thrust direction even when vibration is externally applied to the disk device by configuring the thrust suction force of the rotor magnet 23 to a required suction force. No flexible disk 5
Height can be kept constant. However, when a large impact is applied from the outside, the spindle 21 moves in the thrust direction within the range of the gap 30a. However, in this case, as described in the reference example 1 of FIG.
By setting 30a to 0.15 mm or less, it is possible to provide a disk device that can perform good magnetic recording and reproduction.

According to the present embodiment, the spindle 21 does not move in the thrust direction for a slight vibration. In this respect, it is superior to the other reference examples, FIGS. 1 and 2.

[Effect of the invention]

As described above, the present invention provides a spindle for guiding the center of a disk hub provided at the center of a disk, a spindle bearing for supporting the spindle, and the disk hub on the disk side with respect to the spindle bearing of the spindle. A disk rotation drive device provided with a hub base and a rotor for receiving, wherein a female screw portion is provided at an end of the spindle opposite to the hub base, and the spindle is engaged with the female screw portion and moves in the thrust direction of the spindle. Along with placing screws to regulate the amount,
A concave portion for accommodating the screw is formed at an end of the spindle bearing opposite to the hub base. With such a configuration, the protrusion to the lower surface of the disk device is reduced. This makes it possible to reduce the thickness of the entire disk drive device.

[Brief description of the drawings]

1 and 2 are sectional views of a spindle motor according to a reference example of the present invention. FIG. 3 is a sectional view of the disk rotation driving device according to the embodiment of the present invention. FIG. 4 is a sectional view of a conventional spindle motor. 4… Jacket, 5… Flexible disk, 6…
... Chucking hub, 21 ... Spindle, 22 ... Rotor magnet, 23 ... Rotor, 24 ... Hub stand, 25 ...
Metal bearing, 26 …… Stator, 27 …… Motor frame, 31, 31a …… Thrust washer, 32,32a …… Magnetic head

 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-61-196464 (JP, A) JP-A-58-187615 (JP, A) JP-A-60-213240 (JP, A) JP-A 61-196240 34771 (JP, A) Fully open 1981-36312 (JP, U) Fully open 1986-93855 (JP, U) Fully open, 60-183961 (JP, U) Fully open, 61-98269 (JP, U) Japanese Utility Model Showa 63-29262 (JP, U) Japanese Utility Model Showa 63-74755 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] A spindle for guiding the center of a disk hub provided at the center of a disk; a spindle bearing for supporting the spindle; and a hub base for receiving the disk hub on the disk side of the spindle bearing of the spindle. In the disk rotation drive device provided with, a female screw portion is provided at an end of the spindle opposite to the hub base, and a screw that engages with the female screw portion and regulates the amount of movement of the spindle in the thrust direction is provided. A disk rotation drive device, wherein a recess for accommodating the screw is provided at an end of the spindle bearing opposite to the hub base.