JPS61124253A - Rotary machine - Google Patents

Abstract

PURPOSE:To eliminate the influence of a load variation by forming a coil stationary unit at part of a laminated sheet coil assembly, and directly securing to a stationary frame by the coil stationary unit to eliminate a coil substrate, thereby shortening an air gap length. CONSTITUTION:In a rotary machine 2 in which a laminated sheet coil assembly 22 is opposed through air gaps to a rotor magnet 12 and a rotor yoke 14, a coil stationary unit 26 is projected integrally form the assembly 22. The unit 26 may be, for example, formed by extending insulating sheet and film between coil elements. The assembly 22 is directly secured to the base 4 by the unit 26. Thus, since a coil substrate may not be used, the air gap length may be shortened that much in the thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a coil fixed magnet and yoke rotating type rotating device such as a brushless motor.

[Conventional technology]

Recently, efforts have been made to make disk recording and playback devices smaller and lighter, especially for still image recording and playback.As a result, the disk drive motors built into such devices have also become smaller and lighter. It is being

For example, rare earth magnets are used in the rotor magnets of brushless motors for disk drives in recent years for recording and reproducing still images. Furthermore, as motors become smaller, the bearings used in these motors also become smaller, and the load in the axial direction applied to the bearings also becomes smaller. The model of this) motor is also shifting from a fixed yoke type to a rotating yoke type.

FIG. 3 is a sectional view of the yoke rotation type brushless motor, which is the above-mentioned rotation device. As shown in the figure, the yoke rotation type brushless motor 2' has a shaft 6 fixed to the base 4 by press fitting or adhesive. A rotor unit 8 is provided on the shaft 6 via a bearing 10,
A rotor magnet 12 is also mounted on the upper part of the rotor unit 8. A coil board 18 having a laminated sheet coil assembly 16 between the rotor magnet 12 and the rotating yoke 14 is fixed to the base 4 by a board holder 20. The coil assembly 16 and coil board 18 and the rotor magnet 12 and rotating yoke 14 are spaced apart from each other, and by applying a current to the coil assembly 16, the rotor unit 8 to which the rotor magnet 12 and rotating yoke 14 are fixed is rotated. It rotates around the shaft 6.

In a motor having such a configuration, the distance d' between the lower surface of the rotor magnet 12 and the upper surface of the rotating yoke 14 is called a gap, and this gap d'
and generally defines the magnetic flux density passing through this gap d′
As the width becomes narrower, the starting torque of the motor increases, the sacrificial load rotation speed decreases, and the motor becomes more resistant to load fluctuations.

By the way, in the conventional yoke rotation type motor, the gear 7
Since the coil assembly 16 and the coil substrate 18 are disposed between the coil assembly 162 and the coil substrate 18, there is a problem in that the gap d' cannot be narrowed.

〔the purpose〕

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a rotating device that can narrow the gap between the rotor magnet and the rotating yoke, and is thereby resistant to load fluctuations.

〔Example〕

Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 is a sectional view of a yoke rotating brushless motor as an embodiment of a rotating device according to the present invention, and the motor 2 shown in the same figure has the same function as the conventional motor 2' shown in FIG. 3. Elements are numbered the same.

The feature of this embodiment is that instead of the conventional coil assembly 16 and coil board 18, a coil assembly 22 is directly fixed to the base 4 by a board holder 20.

FIG. 2(a) is a plan view of the coil assembly 22;
N(b) is a partially enlarged cross-sectional view of the coil assembly 22, and as shown in FIG. It has a fixed part 26. In addition, as shown in Figure @2, the coil element 24 is an insulating sheet 30.
They are formed on the top by etching or electroplating, and are divided and arranged in a number corresponding to the number of phases with respect to the number of poles of the rotor magnet 12.

In the figure, 28 is a conductor layer forming the coil element 24, 30' is an adhesive and insulating coil, and 32 is a through hole.

In the coil fixing part 26, an insulating sheet 30, an adhesive layer, and an insulating coil 30' are extended outward from the coil element 24 in the student direction, and a reinforcing agent such as an insulating resin is applied between the sheet 30 and the coil 30' to increase the thickness of the coil element 24. It is filled accordingly.

As described above, according to this embodiment, since there is no coil substrate, the gap d can be narrowed.

As mentioned above, there are two methods for forming the coil element 24: etching and plating. When etching is used, it is extremely easy to provide a conductor layer also on the coil fixing part 26 (that is, etching is not required). At this time, the thickness of the coil element 24 portion of the coil assembly 22 and the coil fixing portion 2
6 can be made equal in thickness. In addition, in the case of plating, electrolytic copper can be grown on the coil fixing part 26 in the same way as on the coil element 24 part, so the thickness can be easily controlled in this case as well.

As described above, the present invention is applicable to both the etching method and the plating method.

Furthermore, the present invention is not limited to the number of poles or phases of the motor. Furthermore, in the embodiment, the coil fixing portion 26 is provided outside the arrangement of the coil elements 24;
You can also write H inside the array of 4;=.

〔Effect of the invention〕

As described above in detail and specifically, according to the present invention,
By removing the coil substrate and forming a coil fixing part in a part of the laminated sheet coil assembly, the coil assembly is fixed directly to the fixing frame at this fixing part, thereby reducing the distance between the rotor magnet and the rotating yoke. Since the gap can be narrowed, load fluctuation and other performance characteristics of the rotating device can be improved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a rotating device according to an embodiment of the present invention, FIGS. 2(a) and 2(b) are a plan view and an enlarged sectional view of a coil assembly, respectively, and FIG. 3 is a sectional view of a conventional rotating device. It is. In the figure, 2...Rotating device 12...Rotor magnet 14...Rotating yoke 22...Coil assembly 724...Coil Element 26... is a coil fixing part. Figure 1

Claims (1)

[Claims] (1) It has a coil assembly in which a plurality of sheet-shaped coils are stacked, and a rotor magnet and a rotating yoke are arranged facing each other to sandwich the coil assembly, so that the rotor magnet and yoke rotate integrally. 1. A rotating device configured as follows: A coil fixing portion is provided on an outer circumferential portion or an inner circumferential portion of the coil assembly, and the coil assembly in the coil fixing portion is directly fixed to a fixed frame.