JPH04289755A - Spindle motor - Google Patents

Abstract

PURPOSE:To constitute a spindle motor for driving a disc of a reduced number of components and to make thin the spindle motor. CONSTITUTION:A spindle hub 2 secured to a shaft 1 is provided with a disc supporting face 2a extending perpendicularly to the shaft. A rotor frame 6 fixed with a ring magnet 7 is also secured to the spindle hub 2. A flat coil 8 is disposed oppositely to the ring magnet 7 between the disc supporting face 2a and the ring magnet 7. When a disc 3 having a magnetic disc hub 3a is mounted in the center under that state, the disc 3 provides a rotary magnetic path yoke. Since a motor is constituted of reduced number of components, it can be made thin and since the disc serves as the rotary magnetic path yoke, vibration can be suppressed in an opposing surface type spindle motor.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spindle motor for driving a disk, which is an optical or magnetic recording medium.

0002

[Prior Art] Regarding a conventional spindle motor, Fig. 2
Explain using. In FIG. 2, a spindle hub 2 is fixed to a shaft 1, and a rotor frame 6 having a rotor magnet 7 is attached to the spindle hub 2. Further, a stator coil 8 is arranged at a position facing the rotor magnet 7, and a magnetic path yoke 9 is further aligned and fixed to the housing 4. Further, a bearing 5 is fixed to the housing 4, and the shaft 1 is rotatably attached to the bearing 5. On the other hand, a clamp magnet 10 for holding the disk 3 is fixed to the other end opening of the spindle hub 2.

0003

[Problems to be Solved by the Invention] However, in the conventional configuration as described above, two magnets of similar shapes, the rotor magnet and the clamp magnet,
They are placed in the upper and lower positions to share their respective functions, and this is an obstacle to the disk spindle motor, which is aiming to be thinner. In addition, sufficient consideration must be given to the material and thickness of the magnetic seal so that the magnets do not affect each other.

[0004]Furthermore, although a planar opposing type is effective in reducing the thickness, a fixed magnetic path yoke has large problems such as axial vibration and noise. Further, in order to eliminate the axial vibration, it is possible to solve the problem by making the magnetic path yoke a rotary type, but the current configuration has the problem of becoming more complicated and making it even more difficult to reduce the thickness.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a spindle motor that has a reduced number of parts, is thinner, and has less vibration.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the spindle motor of the present invention is a flat-faced spindle motor in which a stator coil and a magnet are arranged facing each other, and the spindle motor is fixed to a shaft and the magnet is fixed. The spindle hub to which the rotating yoke is fixed has a disk support surface to regulate the axial position of the disk.
A stator coil is disposed between a magnet and a disk support surface, and the stator coil and magnet are opposed to each other in a plane.

[0007]

[Operation] As described above, the rotor magnet and the clamp magnet are shared, and the disk itself functions as a rotating magnetic path yoke, so the number of parts is extremely small and the thickness is reduced. At the same time, a plane-opposed spindle motor with a rotary magnetic path yoke can be configured extremely easily, and can be manufactured at low cost.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, a spindle hub 2 is accurately fixed to a shaft 1 by shrink fitting, press fitting, or the like. Further, a ring-shaped magnet 7 is fixed to the rotor frame 6 and fixed to the spindle hub 2 by caulking. This frame assembly is rotatably attached to the housing 4 via bearings 5. In addition, since the flat coil 8 is located between the ring-shaped magnet 7 and the disk support surface 2a of the spindle hub 2, it must be inserted into a predetermined position before the rotor frame 6 is caulked and fixed to the spindle hub 2. Alternatively, the inner diameter may be increased or the shape may be changed by cutting out a portion, and then fixed to the housing 4 with screws or the like. Then, a disk 3 having a magnetic disk hub 3a in the center is mounted.

According to the above configuration, since a magnetic path is formed between the rotor magnet and the disk hub, by disposing the stator coil between them, the disk hub can be attracted and clamped by a single rotor magnet, and rotated. It enables two functions: giving power.

0010

[Effects of the Invention] As described above, in the present invention, a single rotor magnet provides clamping force and rotational force, and the disk serves as a rotating magnetic path yoke, so a motor can be constructed with an extremely small number of parts. This allows for a thinner design. Furthermore, since the disk is a rotating magnetic path yoke, it is possible to reduce vibration, which is a problem with the planar facing type.

[Brief explanation of the drawing]

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

[Figure 2] Cross-sectional view of a conventional spindle motor

[Explanation of symbols]

1 Shaft 2 Spindle hub 2a Disc support surface 6 Rotor frame 7 Ring-shaped magnet 8 Flat coil

Claims (1)

[Claims] Claim 1: A spindle hub fixed to a shaft,
A disk support surface extending perpendicular to the shaft is provided, a disk-shaped rotor frame to which a ring-shaped magnet is fixed is fixed, a flat coil is disposed between the ring-shaped magnet and the disk support surface, and the flat coil and the ring-shaped magnet face each other in a plane.