JPH1094206A - Spindle motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify soldering work by fixing the end part of a flexible printed circuit board onto the inner periphery part of a stator end surface, and decrease the width of a spindle motor even if it is of a type which requires large driving current by bonding two flexible printed circuit boards whose shapes of a connecting part with a winding are different from each other as in an embodiment. SOLUTION: One end part where connecting lands 11a, 11b, 12a, and 12b for two flexible printed circuit boards 11, 12 are formed, is fixed to the inner periphery part of the end surface of a stator core 4 respectively. The connecting lands 11a, 11b, 12a, and 12b of the flexible printed circuit boards 11, 12 and the end part of a winding 3 applied on the stator core 4 are electrically- connected, and the flexible printed circuit boards 11, 12 are taken out to the outside through a key way 13 formed on a shaft 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator core for use in a hard disk drive (hereinafter referred to as HDD) or the like having a plurality of salient poles each wound around a fixed shaft provided on a base. The rotor in which an annular magnet is arranged on the inner surface is fixed, and the rotor is fixed via a pair of ball bearings so that the annular magnet faces the salient pole of the stator core with a predetermined gap. Spindle motor rotatably mounted on shaft (International Patent Classification H02K
3/52), and is particularly characterized by an electrical connection structure between a winding provided on a stator core and an external drive circuit.

[0002]

2. Description of the Related Art Conventionally, as a method of relaying a winding of a spindle motor to a connector for connecting to an external drive circuit, there is a method shown in FIG. FIG. 3 is a cross-sectional view of a conventional HDD spindle motor. Reference numeral 1 denotes a fixed shaft having one end fixed to a base 2.

[0003] A stator core 4 having a plurality of salient poles, each of which is provided with a winding 3, is fixed to the outer periphery of the fixed shaft 1. An annular magnet 5 is rotatably mounted on the fixed shaft 1 via a pair of ball bearings 7a and 7b so as to face the salient pole of the stator core 4 with a predetermined gap.

The wire ends of the windings 3 are respectively connected to lead wires 8, and these lead wires 8 pass through through holes 9 leading to the ends of the fixed shaft 1, and are connected to connection terminals 1 of a terminal plate 10.
The terminal plate 10 is fixed by being pressed into the opening of the through hole 9. Then, it is connected to an external drive circuit (not shown) via the connection terminal 10a.

[0005]

However, in the conventional configuration, the work of soldering the winding and the lead wire is difficult because both are not fixed, and the processing of the through hole in the fixed shaft is complicated. For this reason, there is a problem in that it takes a long time to process, and furthermore, since the lead wire is passed through the through-hole, the assembling work is also troublesome.

[0006]

In order to solve the above-mentioned problems, a spindle motor according to the present invention is characterized in that one end of a flexible circuit board on which connection lands are formed is fixed to an inner peripheral portion of an end face of a stator core. Electrically connect the connection land of the flexible circuit board and the end of the winding,
According to the present invention, it is characterized in that the winding can be energized through the flexible circuit board.
Since the connection lands of the flexible circuit board are fixed to the end surface of the stator core, the electrical connection work by soldering the connection lands and the ends of the windings is simplified.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a spindle motor according to a first aspect of the present invention, a stator shaft having a plurality of salient poles, each of which is wound on an outer periphery of a fixed shaft provided on a base, is fixed. A rotor in which an annular magnet is disposed on a side surface is rotatable on the fixed shaft via a pair of bearings such that the annular magnet faces the salient pole of the stator core with a predetermined gap. In the mounted spindle motor, one end of the flexible circuit board on which the connection land is formed is fixed to the inner peripheral portion of the end face of the stator core, and the connection land of the flexible circuit board and the end of the winding are connected to each other. The winding is electrically connected to the winding through the flexible circuit board, and the connection land of the flexible circuit board is a stator. Because it is fixed to the end face of the A,
Electrical connection work by soldering the connection lands and the ends of the windings is easy.

According to a second aspect of the present invention, in the spindle motor, the flexible circuit board is formed by laminating two flexible circuit boards having connection lands formed at end portions thereof different from each other. 2. The spindle motor according to claim 1, wherein the connection lands are fixed to an inner peripheral portion of an end face of the stator core such that the connection lands are respectively exposed. Because of the superposition, even in a motor requiring a large driving current, it is not necessary to increase the width of the flexible circuit board.

Next, in a spindle motor according to a third aspect of the present invention, the flexible circuit board is led out through a key groove formed on an outer peripheral surface of the shaft. 1. The spindle motor according to 1, wherein a key groove is provided on an outer peripheral surface of a shaft for facilitating pulling out of the flexible circuit board to the outside of the motor, thereby facilitating assembly and shortening a processing time of the shaft as compared with a through hole. And can reduce costs.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS.
FIG. 1 is a sectional view of an HDD spindle motor according to an embodiment of the present invention, and the same components as those of the conventional example shown in FIG. 3 are denoted by the same reference numerals.

One of the features of this embodiment is that a flexible circuit board is used instead of the lead wire 8. In this flexible circuit board, two flexible circuit boards 11 and 12 are overlapped and joined, and the shape of the end portion on which the connection lands 11a and 11b and 12a and 12b are formed is as shown in FIG. And the connection lands 11a, 11b, 12a, 12b
Are also different from each other. The ends of the two bonded flexible circuit boards 11 and 12 are
It is fixed to the inner peripheral portion of the end face of the stator core 4 by an adhesive. At this time, the connection lands 11a, 11b, 1
The positions of the connection lands 11a, 11b, 12a, and 12b are set such that the connection lands 11a, 11b are exposed in a plane.

The fixed connection lands 11a, 11
The ends of the winding 4 are soldered to b, 12a and 12b. Also, the two bonded flexible circuit boards 1
The reference numerals 1 and 12 are guided to the end of the fixed shaft 1 in a state where the reference numerals 1 and 12 are joined and fixed to the outer periphery of the fixed shaft 1 in a key groove 13 formed in the axial direction. The reason why the two flexible circuit boards 11 and 12 are used here is to avoid that if the power consumption of the spindle motor is large, the width of the flexible circuit board is inevitably wide and the keyway 4 is also wide. .

[0013]

As described above, according to the spindle motor of the present invention, the soldering operation is simplified by fixing the end of the flexible circuit board to the inner peripheral portion of the end face of the stator. By bonding two flexible circuit boards having different shapes of connection portions to the windings, the width can be reduced even in a spindle motor of a type requiring a large drive current.

Further, by providing the key groove on the outer peripheral surface of the shaft, it is possible to easily pull out the flexible circuit board to the outside of the motor, and to provide a spindle motor which is inexpensive and requires no labor for assembly. Become.

[Brief description of the drawings]

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

FIG. 2 is a plan view of a stator core of the HDD spindle motor according to the embodiment of the present invention;

FIG. 3 is a sectional view of a conventional HDD spindle motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixed shaft 2 Base 3 Winding 4 Stator core 5 Annular magnet 6 Rotor 7a, 7b Bearing 11, 12 Flexible circuit board 11a, 11b, 12a, 12b Connection land 13 Keyway

Claims (3)

[Claims] 1. A rotor having a stator core having a plurality of salient poles, each of which is wound on the outer periphery of a fixed shaft provided on a base, and having a ring-shaped magnet disposed on an inner surface thereof.
A spindle motor rotatably mounted on the fixed shaft via a pair of bearings such that the annular magnet is opposed to the salient poles of the stator core with a predetermined gap therebetween. The one end on which the land is formed is fixed to the inner peripheral portion of the end face of the stator core, and the connection land of the flexible circuit board and the end of the winding are electrically connected to each other through the flexible circuit board. A motor capable of energizing the winding. 2. The flexible circuit board is formed by laminating two flexible circuit boards having connection lands formed at end portions thereof different from each other, and
The spindle motor according to claim 1, wherein the connection lands are fixed to an inner peripheral portion of an end face of the stator core so as to be exposed. 3. The spindle motor according to claim 1, wherein the flexible circuit board is led out through a keyway formed on an outer peripheral surface of the shaft.