JP2789502B2 - Spindle motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor generally called a spindle motor used for rotating a disk (magnetic disk, optical disk) or the like.

[0002]

2. Description of the Related Art Conventionally, this type of motor (not shown) has
It has a frame attached to the disk device, and a rotor rotatably provided by a bearing on a shaft erected on the frame. A disk is mounted on the rotor. Further, the rotor is provided with a plurality of mounting holes for the disk holding cap. Since this spindle motor is used in a disk drive, it requires high performance, and strict dimensional control of each part and smooth rotation of the rotor are required.

[0003]

However, such a spindle motor has the following problems. The frame or rotor must be replaced when the frame or rotor is damaged, when distortion is discovered during the inspection, or when the dimensions are not within the specified tolerances. The rotor must be replaced as a whole, which increases the cost. When machining the mounting hole of the disk holding cap, if the thickness between the hole and the hole in which the bearing is inserted (for example, the portion indicated by reference numeral 20 in FIG. 2) is thin, the number of the mounting holes is equal to the number of the mounting holes. It may protrude into the hole into which the bearing is inserted. For this reason, the outer ring of the bearing to be inserted later may be deformed, and a protruding portion may be formed by the protruding portion in the outer ring. Therefore, if the number of the mounting holes and the number of the rotating elements of the bearing are the same or differ by one, all the rotating elements may ride on the protruding portion in the outer race at substantially the same time, and the smoothness of the rotor may occur. Rotation is prevented, and high performance cannot be obtained.

[0004]

SUMMARY OF THE INVENTION The present invention firstly comprises a frame mounted on a disk drive, and a rotor rotatably mounted on a shaft erected on the frame by bearings and having a disk mounted thereon. In a spindle motor in which a plurality of mounting holes for a disk holding cap are formed in the rotor , the rotor includes a disk mounting portion and the disk mounting portion.
It consists of a magnet mounting part directly connected to the disk mounting part,
The disk mounting part and the magnet mounting part are individually replaceable.
Or the frame comprises a shaft support and the disc
It consists of a mounting part to be mounted on the device, and
Secondly, according to the configuration in which the attachment portions are individually replaceable , the frame includes a frame attached to the disk device, and a rotor rotatably provided by a bearing on a shaft erected on the frame and bearing a disk. In a spindle motor in which a plurality of mounting holes for a disk holding cap are formed in the rotor, the mounting holes are circumferentially equally spaced.
It is disposed, and, with the configuration that number are What different two or more with respect to the number of rolling element of the bearing, has solved the above problems.

[0005]

In the rotor or frame, the disk mounting portion and the magnet mounting portion, and the shaft supporting portion and the mounting portion are separated by a circle centered on the shaft.
It can be divided, respectively. Thus, each can be partially replaced. Also, since the mounting holes for the disk holding caps are formed at equal intervals in the circumferential direction and with a difference of two or more than the number of rotating elements of the bearing , all of the mounting holes are formed in the projecting portions in the outer ring of the bearing. Of the rotating elements do not ride at the same time.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. The spindle motor 10 has a frame 11 attached to the disk device A, a shaft 12 erected on the frame 11, and a rotor 14 rotatably provided on the shaft 12 by bearings 13,13.

[0007] The frame 11 is provided with a stator 15. The frame 11 includes a shaft support portion 111 into which the shaft 12 is press-fitted or integrally formed, and a mounting portion 112 mounted to the disk device A. The mounting portion 112 has a ring shape and is press-fitted into the shaft support portion 111. The press-fit portion has a circular shape about the axis 12.
In addition, screw engagement may be used instead of press fitting.

The bearing 13 (see FIG. 2) includes the inner and outer races 1.
31 and 132 and eight balls 133 (rotating elements). The bearing 13 has a ball 133
Instead, a bearing using a roller (not shown) may be used.

A cylindrical magnet 16 is provided on the inner periphery of the rotor 14, and a plurality of disks D are mounted on the outer periphery. Therefore, the rotor 14 rotates integrally with the disk D by the magnetic action of the stator 15 and the magnet 16. The rotor 14 includes a magnet mounting portion 141 in which the magnet 16 is loaded and a disk mounting portion 142 on which the disk D is mounted. The magnet mounting portion 141 has a ring shape and is press-fitted into the disk mounting portion 142. Have been. The press-fit portion has a circular shape about the axis 12. In addition, screw engagement may be used instead of press fitting.
Further, five screw holes (mounting holes) 18 for mounting a cap 17 for holding the disk D are formed in the rotor 14 at regular intervals (see FIG. 2). In this case, the number of screw holes 18 is three less than the number of balls 133.

Therefore, when the frame 11 or the rotor 14 is damaged during the assembling process, when a distortion is found in the inspection stage, or when the dimensions are not within a predetermined tolerance, for example,
That part may be replaced. For example, when the mounting portion 112 of the frame 11 is distorted, the mounting portion 112 is detached from the shaft support 111, and the other mounting portion 1 without distortion is removed.
12 can be exchanged.

When the specifications of the spindle motor 10 are changed, each part may be replaced according to the change.
For example, if the number of mounted discs D is changed,
What is necessary is just to replace it with another disk mounting part 142 having a different length. Therefore, the magnet 16 and the magnet mounting portion 141 can be commonly used. The same applies to the frame 11. Further, a portion to be press-fitted into the shaft 12 may be unitized and manufactured in advance, and another portion may be incorporated into the unit according to use.

Further, the screw hole 18 has a female screw formed by tapping a lower hole formed in the rotor 14.
For this reason, at the time of machining the screw hole 18, the portion between the bearing press-fit hole 19 into which the bearing is press-fitted and the screw hole 18 (the portion indicated by reference numeral 20) protrudes into the bearing press-fit hole 19, and the protrusion 21 is formed. There are things. For this reason, a protrusion (not shown) is generated by the protrusion 21 on the inner surface of the outer ring 132 of the bearing 13 to be inserted later, so that the ball 133 rides on the protrusion during the rotation of the rotor 14 and passes therethrough. Become. However, since the number of screw holes 18 is three less than the number of balls 133, all the balls 13
3 does not ride on all protrusions 20 at the same time. Therefore, the smooth rotation of the rotor 14 is not hindered.

In FIG. 2, a gap S is provided between the outer race 132 and the bearing press-fitting hole 19, which is exaggerated for easy understanding of the description. Actually, the protrusion 21 and the outer ring 132 are deformed, and the gap S is almost eliminated.

[0014]

According to the spindle motor of the present invention, the following effects can be obtained. According to the first or second aspect of the present invention, it is possible to replace only a damaged portion of the frame or the rotor, a distorted portion, or the like. Further, when the specifications of the spindle motor are changed, only that part can be replaced, and the other parts can be used as common parts. According to the third aspect of the present invention, all the rotating elements do not simultaneously ride on the protrusions protruding into the outer ring of the bearing due to the protrusions generated when the mounting holes are formed, and the rotor can rotate smoothly. it can.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along an axis of a spindle motor of the present invention, and is also a sectional view taken along the arrow 1-1 in FIG.

FIG. 2 is a plan view of the rotor in a state where a bearing is press-fitted.

[Explanation of symbols]

 A disk device D disk 10 spindle motor 11 frame 12 shaft 13 bearing 14 rotor 17 cap (disk holding cap) 18 screw hole (mounting hole) 133 ball (rotating element)

Claims (3)

(57) [Claims] 1. A frame mounted on a disk device, and a rotor rotatably mounted on a shaft erected on the frame by bearings and having a disk mounted thereon, wherein the rotor has a mounting hole for a disk holding cap. In the spindle motor in which a plurality of pieces are formed, the rotor is directly attached to the disc mounting portion and the disc mounting portion.
It is composed of a magnet mounting part coupled to the disk mounting part.
A spindle motor, wherein the magnet mounting portions are individually replaceable . 2. A frame attached to a disk drive.
And a bearing on the shaft erected on the frame
A rotor that is rotatably mounted and has a disk mounted
And the rotor has a mounting hole for a disk holding cap.
In a plurality of spindle motors, the frame is attached to a shaft support and the disk device.
The shaft support and the mounting part are individually interchanged.
A spindle motor , which is interchangeable . 3. A frame which is mounted on a disk device, and a rotor which is rotatably provided by a bearing on a shaft erected on the frame and on which a disk is mounted, wherein the rotor has a mounting hole for a disk holding cap. In a spindle motor in which a plurality of holes are formed, the mounting holes are arranged at equal intervals in a circumferential direction, and
One, characterized in that the number is present What different two or more with respect to the number of rolling element of the bearing, spindle motor.