JPH0666260U - Brushless motor stator device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a stator device of a brushless motor for disk rotation drive, which can be made thinner. A radial insertion hole 9 for inserting a coil is provided in a printed circuit board 8, and one side of a coil 7 wound around a stator core 6 is inserted into this insertion hole to insert the wound coil and the printed circuit board. The hole and the resin member 11 are integrally formed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a stator device for a brushless motor used in office automation equipment, audio equipment, and video equipment.

[0002]

[Prior art]

 Recently, there has been a demand for small and thin brushless motors used in response to the demand for small size of various devices. In particular, a disk device such as a floppy disk device is widely used as an information storage device, and there is a demand for development of a 2/3 inch and 1/2 inch heat disk device, especially for a handy type A4 size computer. In response to such demands, there has been a demand especially for a rotary drive device to be thin.

The conventional brushless motor will be described below by taking a conventional rotary drive brushless motor that rotationally drives a disk as an example.

FIG. 5 shows the structure of a conventional brushless motor for rotationally driving a disk. 21 is a shaft, 22 is a spindle hub, 23 is a rotor frame, 24 is a drive magnet, 25 is a printed circuit board, 26 is a housing, 27 is a stator core, 28 is a ball bearing, 29 is an oil-impregnated bearing, and 30 is a coil.

First, as a disk is inserted into the floppy disk device, the disk hub is magnetically attracted by the hub magnet 31, and at the same time, the shaft 21 is inserted into the motor shaft insertion hole of the disk hub. Then, the drive pin 32 is inserted into the drive pin insertion hole, and while the motor starts rotating and the rotor makes one rotation, the drive pin 32 is chucked in the drive pin insertion hole and the disc rotates integrally with the rotor. .

The rotor of the motor rotates smoothly around a shaft 21 supported by a ball bearing 28 and an oil-impregnated bearing 29, and a spindle hub 22 fixed to the shaft 21 by a method such as shrink fitting is attached to the shaft 21. The rotor frame 23 is caulked and attached via the spindle hub 22. A main magnet 24 is adhered to the inner surface of the hanging portion of the cup-shaped rotor frame 23, and a frequency generating magnet (hereinafter abbreviated as FG magnet) 33 is provided on the lower surface of the flange portion extending outward from the lower end of the hanging portion. It is mounted, magnetized for frequency power generation, and the generator line element is arranged on the ponto board 25 facing the magnetized surface. As the motor rotates, a generated voltage is generated, and the generated voltage is supplied to the motor control circuit. The motor is controlled at a constant speed by inserting it.

In the stator of the motor, a coil 30 is wound around an insulated stator core 27, the stator core 27 is attached to a housing 26 to which a ball bearing 28 and an oil-impregnated bearing 29 are fixed, and the housing 26 is crimped to a printed circuit board 25. It is fixed. A current is supplied to the coil 30 from the printed board 25, a magnetic field is generated from the salient poles of the stator core 27, and the rotor frame with the drive magnet 24 is rotated.

When the distance from the printed circuit board of the motor to the top surface of the rotor frame is taken as the motor height, the motor height shown in FIG. 5 is the thickness of the printed circuit board, the thickness of the wound coil on the printed board side, and the insulation. The thickness of the stator core including the material, the thickness of the wound coil on the hub magnet side, the thickness of the rotor frame, the gap between the rotor frame and the coil so that the rotor does not contact, and the printed circuit board and the coil. It is expressed as the sum of the gaps.

[0009]

[Problems to be solved by the device]

 However, in the above-described conventional configuration, in order to reduce the motor height, there is no choice but to reduce the number of laminated stator cores, reduce the number of coil winding layers, or reduce the plate thickness of the rotor frame or print substrate. If the number of laminated stator cores is reduced or the number of coil winding layers is reduced, a sufficient magnetic field cannot be generated, and there is a problem that the torque characteristics are deteriorated. If the thickness of the rotor frame or the printed circuit board is reduced, the strength of the motor will decrease. In order to achieve the required motor height, there are the above-mentioned restrictions, which hinders the thinning of the disk rotation drive device.

An object of the present invention is to solve the above-mentioned conventional problems and to provide a stator device for a brushless motor for rotating a disk, which is capable of maintaining performance and realizing a thin structure.

[0011]

[Means for Solving the Problems]

 In order to achieve this object, the brushless motor for rotating a disk according to the present invention is provided with a radial insertion hole for inserting a coil on a printed circuit board, and a stator having one coil wound around a stator core inserted in this insertion hole. Alternatively, one of the coils wound around the stator core is inserted into the insertion hole, and the wound coil and the coil insertion hole of the printed circuit board are integrally molded with a resin member to form a stator. .

[0012]

[Action]

 With this configuration, one of the coils wound around the core is inserted into the coil insertion hole of the printed circuit board, and the height of the coil part inserted into the printed circuit board and the gap between the printed circuit board and the coil are unnecessary. The height of the motor can be reduced only by the amount. Furthermore, the strength of the stator portion is increased by integrally molding the wound coil and the coil insertion hole portion of the printed circuit board with a resin member.

[0013]

【Example】

 Embodiment 1 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1A is a sectional view of a brushless motor for disk rotation driving in a first embodiment of the present invention, and FIG. 1B is an enlarged view of a judgment surface of the brushless motor for disk rotation driving. It is shown. FIG. 2 shows an example of a coil insertion hole provided in a printed circuit board, FIG. 3 (a) shows one salient pole portion of a stator core around which a coil is wound, and FIG. 3 (b) shows FIG. ) Shows the coil inserted into the coil insertion hole.

In FIGS. 1, 2 and 3, 1 is a shaft, 2 is a rotor frame, 3 is a flange frame which also serves as a back yoke of an FG magnet, 4 is a drive magnet, 5 is an FG magnet, 6 is a stator core, 7 Is a coil, 8 is a printed circuit board, 9 is a coil insertion hole, and 10 is a Hall element.

The structure of the brushless motor for rotating a disk according to the first embodiment of the present invention will be described with reference to FIGS. 1, 2 and 3.

The chucking principle of the disk is the same as that of the conventional example, and therefore its description is omitted. The shaft is supported by oil-impregnated bearings for radial support, the rotor frame is supported by washers by ball bearings for thrust load support, and the shaft is press-fitted into the rotor frame. Rotates smoothly around the shaft.

A drive magnet 4 is fixed to the inside of the outer peripheral portion of a cup-shaped rotor frame that constitutes a spindle hub portion of the rotor frame 2, and a flange frame 3 that also serves as a back yoke of an FG magnet is attached to the outside of the outer peripheral portion. The FG magnet 5 is fixed to the flange frame, and the power generating line element is arranged on the printed substrate 8 facing the magnetized surface that is magnetized for frequency power generation, and an FG signal is obtained by the rotation of the motor. The rotor of the motor is controlled by the FG signal and rotates at the set rotation speed.

A printed circuit board 8 is radially provided with coil insertion holes 9 as shown in FIG. 2, the coil 7 is wound around an insulated stator core 6, and one side of the coil 7 wound around the stator core 6 is coiled. The stator structure is to be inserted into the insertion hole 9. In this stator structure, since the stator core 6 approaches the printed circuit board 8 and the positional relationship with the driving magnet changes, one salient pole portion on the outer periphery of the laminated stator core 6 on the rotor frame 2 side is bent to form the plate portion. As a result, a large amount of magnetic flux of the drive magnet 4 is guided to the stator core 6 so that the torque characteristic can be improved.

As can be seen from FIG. 3, the size of the coil insertion hole 9 must be larger than the coil width in the radial direction so that the coil to be inserted comes into contact with the coil insertion hole. Therefore, the gap between the coil insertion holes on the shaft side must be at least the minimum dimension required for drilling, and the number of salient poles in the stator core of the motor is limited.

As described above, according to this embodiment, by the stator structure in which one side of the coil wound around the stator core is inserted into the coil insertion hole of the printed circuit board, the height of the coil portion inserted into the printed circuit board is increased. Thus, the height of the motor can be reduced by the amount that the gap between the printed circuit board and the coil is unnecessary.

Second Embodiment Hereinafter, a second embodiment of the present invention will be described with reference to FIG.

FIG. 4A is a cross-sectional view of a brushless motor for rotating a disk according to the second embodiment, and FIG. 4B is an enlarged view of a judgment surface of the brushless motor. In FIG. 4, the symbols 1 to 10 are the same as those in FIG. The difference from the configuration of FIG. 1 is that the wound coil 7 is molded with a resin member 11.

The structure of the brushless motor for rotating a disk according to the second embodiment of the present invention configured as described above will be described below.

The printed circuit board 8 is provided with coil insertion holes 9 radially around the shaft 1, the coil 7 is wound around an insulated stator core 6, and one of the coils 7 wound around the stator core 6 is wound. The side is inserted into the coil insertion hole 9, and the wound coil 7 and the coil insertion hole of the printed circuit board 8 are integrally molded with the resin member 11 to form a stator structure.

With such a configuration, the motor height can be reduced by the height of the coil portion to be inserted into the printed circuit board and the fact that the gap between the printed circuit board and the coil is unnecessary. Furthermore, the integral molding increases the strength of the stator structure and improves the impact resistance of the disk drive device.

[0027]

[Effect of device]

 As described above, according to the present invention, a plurality of coil insertion holes are radially installed in the printed circuit board, and the coil wound in the coil insertion hole is inserted, whereby the height of the coil portion inserted in the printed circuit board is increased. In addition, the motor height can be reduced to a thinner brushless motor stator device by eliminating the gap between the printed circuit board and the coil. Further, by integrally molding the coil insertion portion and the printed circuit board with a resin material, a stator device having high impact resistance can be obtained.

[Brief description of drawings]

FIG. 1A is a sectional view of a brushless motor for rotating a disc according to a first embodiment of the present invention. FIG. 1B is a half sectional enlarged view of a brushless motor for rotating a disc according to a first embodiment of the present invention.

FIG. 2 is a plan view of a printed circuit board seen from above according to an embodiment of the present invention.

FIG. 3A is a plan view showing one salient pole portion of a stator core around which a coil is wound. FIG. 3B is a plan view seen from above when the coil is inserted into the coil insertion hole.

FIG. 4A is a cross-sectional view of a brushless motor for rotating a disk according to a second embodiment of the present invention. FIG. 4B is an enlarged half cross-sectional view of a brushless motor for driving a disk according to a second embodiment of the present invention.

FIG. 5 is a sectional view of a conventional brushless motor for rotating a disk.

[Explanation of symbols]

 1 Shaft 2 Rotor Frame 3 Flange Frame 4 Drive Magnet 5 FG Magnet 6 Stator Core 7 Coil 8 Printed Circuit Board 9 Coil Insertion Hole 10 Hall Element 11 Resin Member

Claims (2)

[Scope of utility model registration request] 1. A stator core having a plurality of salient poles, an exciting coil wound around an insulating portion of the stator core, and a printed circuit board for supplying power to the exciting coil. The printed circuit board includes the number of salient poles of the stator core. A stator device for a brushless motor, characterized in that the same number of holes are radially provided, and one winding portion of the coil portion is inserted into the hole of the printed circuit board. 2. A stator core having a plurality of salient poles, an exciting coil wound around an insulating portion of the stator core, and a printed circuit board for feeding power to the exciting coil. The printed circuit board includes the number of salient poles of the stator core. The same number of holes are provided radially, one winding portion of the coil portion is inserted into the hole of the printed circuit board, and the exciting coil wound with a resin member and the printed circuit board are integrally molded. Motor stator device.