JP2857784B2 - Spindle motor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a spindle motor for rotating a recording member such as a magnetic disk.

(Conventional technology and its disadvantages)

Generally, a fixed shaft type spindle motor includes a mounting bracket, a shaft member fixed to the mounting bracket, and a hub member rotatably mounted on the shaft member via bearing means. A rotor magnet is fixed to the inner peripheral surface of the hub member, a stator is arranged inside the rotor magnet, and a stator and circuit means for controlling rotation of the hub member are attached to the shaft member.

However, in the conventional spindle motor, a through hole extending in the axial direction is formed in the shaft member, and a lead wire from the circuit means is led out through the through hole. Therefore, there are problems to be solved, such as difficulty in forming a through hole, and complicated work for leading out a lead wire.

[Object of the Invention] The present invention has been made in view of the above-mentioned facts, and a main object thereof is to provide an improved spindle motor capable of relatively easily and easily leading a lead means to the outside. It is.

[Summary of the Invention]

According to the present invention, a mounting bracket, a shaft member fixed to the mounting bracket, a hub member rotatably mounted on the shaft member, a rotor magnet mounted on the hub member, and a shaft member An outer peripheral surface of the shaft member from the mounting portion of the stator to an end thereof is flatly cut to generate a lead-out space extending in the axial direction, and an electric power is supplied to the stator. A spindle motor is provided, wherein lead means for electrically connecting are arranged in the lead-out space.

〔Concrete example〕

Hereinafter, a specific example of a spindle motor according to the present invention will be described with reference to the accompanying drawings.

First Specific Example In FIG. 1, the illustrated spindle motor includes a mounting bracket 2, a shaft member 4, and a hub member 6. The mounting bracket 2 has a substantially disk shape and is mounted on a frame (not shown) of the drive device as required.

The shaft member 4 is fixed to the mounting bracket 2 by means such as press fitting, and a hub member 6 is rotatably mounted on the shaft member 4 via a pair of bearing members 8 and 10. A yoke member 12 is mounted on the inner peripheral surface of the hub member 6.
An annular rotor magnet 14 is provided on the inner peripheral surface at the
Is installed. In the specific example, as shown in FIG. 1, one end of the hub member 6 is supported by the bearing member 8 via the yoke member 12, and the other end is connected to the yoke member 12 and the bush member.
It is supported by the other bearing member 10 via 16. Magnetic fluid sealing mechanisms 18 and 20 are provided outside the bearing members 8 and 10, and a preload is applied between the annular bush member 22 of one of the magnetic fluid sealing mechanisms 18 and the inner ring of the bearing member 8. A biasing means 24 such as a disc spring is interposed.

A stator 26 is provided inside the rotor magnet 14. The stator 26 is a stator core 28 attached to an intermediate portion of the shaft member 4 (a portion between the pair of bearing members 8 and 10).
And an amateur coil 30 wound on the stator core 28
have. The stator 26 and the other bearing member
A circuit means 32 for controlling the rotation of the hub member 6 is provided between the first and second hubs 10 and 10. The circuit means 32 has a circuit board 34 fixed to the shaft member 4. The circuit board 34 has a Hall element for detecting a circuit angular position of the rotor magnet 14.
Various electrical elements, including 36, are provided. Stator 26
The lead wire 33 from the armature coil 30 is electrically connected to a predetermined terminal portion (not shown) on the circuit board 34, and the lead wire 38 (acting as a lead means) from the circuit board 34 will be described later. Then, it is led out of the mounting bracket 2. In the specific example, an annular flange portion 40 is provided on the shaft member 4 to hold the circuit board 34 in a predetermined position, and a sleeve member 42 is provided between the circuit board 34 and the stator 26 to hold the stator 26 in a predetermined positional relationship. Is interposed.

In the spindle motor as described above, a recording member 43 such as a plurality of magnetic disks is mounted on the outer periphery of the hub member 6 via a spacer member 44 in a stacked state, as shown by a chain line in FIG. The recording member 43 is placed on the flange portion 46 of the hub member 6. Then, with respect to the mounting bracket 2, the shaft member 4, and the stator 26, the hub member 6 (the yoke member 12 and the rotor magnet 14 integrally therewith) and the recording member 43 are driven to rotate in a predetermined direction.

Next, the lead-out mode of the lead wire 38 will be described with reference to FIG. 2 together with FIG.

In a specific example, the following (specifically, the stator 26
(A lower part in FIG. 1 from the mounting part of FIG. 1) is partially cut in a flat shape. The cut flat surface 4a extends to one end (the lower end in FIGS. 1 and 2), and the flat surface 4a, the circuit board 34, the bearing member 10
A lead-out space extending in the axial direction is defined between the inner ring, the bush member 48 of the magnetic fluid seal mechanism 20, and the mounting bracket 2. Further, a slit 50 extending from one end to the other end is formed in the sleeve member 42 corresponding to the flat surface 4a (see FIG. 2). Then, the lead wire 38 from the circuit board 34 is led out below the mounting bracket 2 through the lead-out space defined by the slit 50 of the sleeve member 42 and the flat surface 4a as shown in FIG. In a conventional spindle motor, a through-hole extending from one end to a portion near a circuit board is formed in a shaft member, and a lead wire is led out to the outside through the through-hole. Therefore, processing for forming the through-hole is performed. It is not easy, and the operation for leading the lead wire is complicated, and the manufacturing cost is high. On the other hand, in the spindle motor of the specific example, the lead-out space can be formed by a simple processing of cutting a part of the outer peripheral surface of the shaft member 4, and the lead wire 38 is led out through the lead-out space. Is easy, and the manufacturing cost is reduced.

Second Embodiment FIG. 3 shows a part of a second embodiment of the spindle motor according to the present invention. In the second specific example, no hall element or the like is provided, and the lead wire from the amateur coil is led out of the mounting bracket via the flexible board. In FIG. 3, the same members as those shown in FIGS. 1 and 2 are denoted by the same reference numerals and described.

3, a part of the outer peripheral surface of the shaft member 4 is cut flat like the first embodiment, and the cut flat surface 4a extends from the vicinity of the mounting portion of the stator 26 to one end. The stator 26 has a stator core 28 and an armature coil 30 wound around the stator core 28 as required, and a lead-out wire 33 of the armature coil 30 is attached to a mounting bracket (not shown) via a flexible substrate 62 acting as lead means. ) Is derived outside.

In the second specific example, the flexible substrate 62 has an elongated plate shape, and a winding portion 64 is provided at one end thereof. The flexible substrate 62 is attached to the flat surface 4a of the shaft member 4 by means of an adhesive or the like, and the winding portion 64 is wound around the outer peripheral surface beyond the flat surface 4a with an adhesive or the like. A plurality of terminal portions 66 are provided on the surface of the flexible substrate 62, and lead portions 68 extend linearly in the longitudinal direction from these terminal portions 66, and these lead portions 68 are disposed outside the mounting bracket. It is electrically connected to control means (for example, a microprocessor for controlling the rotation of the motor). In addition, the lead 33 from the amateur coil 30 is electrically connected to the corresponding terminal 66 by means such as solder. The winding portion 64 wound around the shaft member 4 may be used for positioning the stator 26 in the axial direction.

Also in the second specific example, the amateur coil 30
Flexible substrate (lead means) electrically connected to
Is led out through the cut portion formed in the shaft member 4, so that the same effect as in the first specific example is achieved.

As mentioned above, although one specific example of the spindle motor according to the present invention has been described, the present invention is not limited to such specific example, and various modifications and corrections can be made without departing from the scope of the present invention.

In addition, for example, in the specific example, the cut portion extending in the axial direction is formed at one position of the shaft member 4, but the cut portion may be formed at two opposing positions of the shaft member, or at three or more positions. Good.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a specific example of a spindle motor according to the present invention. FIG. 2 is an exploded perspective view showing a shaft member and a sleeve member of the spindle motor of FIG. 1; FIG. 3 is a perspective view showing a part of a second specific example of the spindle motor according to the present invention. 2 Mounting bracket 4 Shaft member 6 Hub member 8 and 10 Bearing member 14 Rotor magnet 26 Stator 32 Circuit means 34 Circuit board 38 Lead wire

Claims (1)

(57) [Claims] 1. A mounting bracket, a shaft member fixed to the mounting bracket, a hub member rotatably mounted on the shaft member, a rotor magnet mounted on the hub member, and a mounting member mounted on the shaft member. And an outer peripheral surface from a mounting portion of the stator to an end of the shaft member is flattened to generate a lead-out space extending in the axial direction, and the stator is electrically connected to the spindle motor. A spindle motor, wherein lead means for connecting to the spindle motor are arranged in the lead-out space.