JP2012226808A - Spindle motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spindle motor capable of achieving thinning of the same with increased suppression of vibration transmission from the spindle motor to a disk.SOLUTION: In a spindle motor 1 which rotates a disk, a rotor frame 16 where the disk is loaded has a stepped portion, with a surface level thereof lower than other portion of the rotor frame 16, on an outer circumference of an upper surface of the rotor frame. A turntable cushion 17 for vibration control is adhered to the upper surface of the stepped portion. Thus, a thickness of the turntable cushion 17 to be adhered to the stepped portion can be increased.

Description

  The present invention relates to a spindle motor.

  2. Description of the Related Art Conventionally, a spindle motor that rotates a disk is known in a disk drive device that records and reads data on a disk that is a circular recording medium such as a CD, a DVD, or a Blu-ray.

  As the spindle motor, for example, a DC brushless motor is used, and includes a turntable for mounting a recording medium and a drive unit that rotationally drives the turntable.

  The drive unit includes a rotor frame, a rotation shaft of a rotor that rotatably supports the rotor frame, and a stator disposed around the rotation shaft of the rotor. Since the turntable needs to rotate synchronously with the rotor, the turntable is fixed to the rotation shaft at the center by press-fitting and bonding, or directly fastened and fixed to the rotor frame.

  Patent Document 1 discloses a technique for finishing not only the surface runout accuracy of the disk mounting surface anti-slip portion of the turntable but also the surface roughness and flatness with high accuracy.

  Also known is a turntable cushion (hereinafter referred to as “TT cushion”) that is used as a damping material that suppresses vibration transmission to the disk. This TT cushion serves as a damping material and also contacts the disk surface. Also plays the role of slip prevention.

JP 2007-12194 A

  By the way, as the spindle motor becomes thinner, the height of the motor and the height of the alignment ring are restricted as the drive mounted becomes thinner. Under such circumstances, there is an increasing demand for suppressing the vibration of the disk, and it is necessary to increase the thickness of the TT cushion, which is a vibration damping component.

  To increase the thickness of the TT cushion, the position of the rotor may be lowered. However, due to the characteristics, changing the configuration of the magnet and winding leads to a decrease in performance, and if these are not changed, the lower part of the rotor and the winding or bearing holder There is a risk of interference.

  In the invention described in Patent Document 1, the disk mounting surface anti-slip portion is cut and cut out, but in this case, the vibration damping performance is reduced by the cutting.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a spindle motor capable of further suppressing vibration transmission from the motor to the disk while realizing a reduction in thickness.

  In order to solve the above problems, the present invention provides a spindle motor for rotating a disk, wherein a step portion lower than the other surface of the rotor frame is provided on the outer circumference of the upper surface of the rotor frame on which the disk is placed. A turntable cushion for vibration suppression is provided on the upper surface of the stepped portion.

  Further, the present invention is characterized in that an upper surface of the turntable cushion attached to the upper surface of the stepped portion protrudes upward from a surface other than the stepped portion of the upper surface of the rotor frame.

  In the rotor frame of the spindle motor for rotating the disk, the present invention is characterized in that a step portion lower than the other surface of the rotor frame is provided on the outer circumference of the upper surface on which the disk is placed. .

  ADVANTAGE OF THE INVENTION According to this invention, the spindle motor which can suppress more the vibration transmission from a motor to a disk can be provided, implement | achieving thickness reduction.

It is a figure which shows one Embodiment of the spindle motor by this invention, Comprising: It is a sectional side view which cut | disconnects a spindle motor in the rotating shaft position, and shows the left side. FIG. 2 is an enlarged view showing a step C of the rotor frame 16 shown in FIG. 1.

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

  FIG. 1 is a diagram showing an embodiment of a spindle motor according to the present invention, and is a side sectional view showing a left side of the spindle motor cut at a rotational axis position.

  The spindle motor 1 includes a rotor 15 and a stator 11. The upper surface of the rotor 15 serves as a turntable, and the shaft 19 that is a rotating shaft is fixed to the center of the rotor frame 16 on which a disk (not shown) is mounted on the upper surface by direct press-fitting or the like. Further, on the inner periphery of the rotor frame 16, a ring-shaped rotor magnet 21 magnetized in the circumferential direction is fixed by press-fitting or bonding. The shaft 19 is supported by a bearing 20 which is an oil-impregnated bearing, for example.

  On the other hand, the stator 11 is formed by winding a stator coil 13 around an insulating member around a stator core 12 formed by laminating silicon steel plates, for example.

  The spindle motor 1 is attached to a mounting plate 10. A centering ring 18 is provided at the center of the rotor frame 16 so that the center of the disk coincides with the center of rotation.

  Further, a step 16a (see FIG. 2) lower than the other surface of the rotor frame 16 is provided on the outer circumference of the upper surface of the rotor frame 16 on which the disk is placed, and the TT cushion 17 for damping is attached to this. It is affixed on the upper surface of the step part 16a. The upper surface of the TT cushion 17 projects upward from the surface of the upper surface of the rotor frame 16 other than the stepped portion 16a.

  FIG. 2 is an enlarged view showing the step C of the rotor frame 16 shown in FIG.

  In the spindle motor 1 of the present embodiment, the thickness of the TT cushion 17 is increased in order to further suppress vibration transmission from the motor to the disk while realizing a reduction in thickness, and the rotor frame 16 is increased without increasing the overall height. The step portion 16a is provided in the TT cushion 17 so that the thickness of the TT cushion 17 can be increased.

  As a spindle motor, the size of the motor from the mounting plate 10 to the upper surface of the TT cushion 17 is limited, and the height B from the upper surface of the TT cushion 17 to the upper surface of the alignment ring 18 is also limited. is there. In the present embodiment, in order to suppress vibration transmission from the motor to the disk while receiving this restriction, attention is paid to increasing the thickness of the TT cushion, and the step 16a having a height C is provided in the motor frame. . Thereby, the thickness of the TT cushion 17 stuck on the level | step-difference part 16a can be increased.

  As described above, according to the present invention described above, the thickness of the TT cushion can be easily increased without changing the internal structure of the motor, and the effect of suppressing vibration transmitted to the disk can be enhanced.

  Further, according to the present invention, by providing the step portion on the rotor frame, the step portion is used for positioning, and the TT cushion can be easily attached.

  Further, according to the present invention, even when the TT cushion is attached, even if the attachment position is shifted, the TT cushion rides on the shoulder of the stepped portion, so that it can be easily identified as viewed from the horizontal direction. it can.

  Although the present invention has been described above, the present invention is not limited to this description, and it goes without saying that various modifications and combinations can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Spindle motor 10 Mounting plate 11 Stator 12 Stator core 13 Coil 15 Rotor 16 Rotor frame 16a Step part 17 Turntable cushion (TT cushion)
18 Alignment ring 19 Shaft 20 Bearing 21 Magnet

Claims (3)

In the spindle motor that rotates the disk,
On the outer circumference of the upper surface of the rotor frame on which the disk is placed, a step portion lower than the other surface of the rotor frame is provided, and a turntable cushion for damping is attached to the upper surface of the step portion. A spindle motor characterized by that.   2. The spindle motor according to claim 1, wherein an upper surface of the turntable cushion attached to an upper surface of the step portion protrudes upward from a surface other than the step portion of the upper surface of the rotor frame. . In the rotor frame of the spindle motor that rotates the disk,
A rotor frame of a spindle motor, wherein a step portion lower than the other surface of the rotor frame is provided on the outer circumference of the upper surface on which the disk is placed.

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