KR980012782A - Stacked stator yoke of flat motor with eddy current reduction - Google Patents

Abstract

The present invention relates to a flat motor, and more particularly, to a stacked type data yoke of a flat motor for achieving an eddy current reduction that improves the efficiency of a motor by reducing the eddy current by stacking a stator yoke in a flat motor. The present invention reduces the generation of eddy currents and reduces current consumption due to eddy currents by constructing a stator yoke by laminating annular thin plate cylindrical pieces in a radial direction coaxially with each other, .

Description

Stacked stator yoke of flat motor with eddy current reduction

The present invention relates to a flat motor, and more particularly, to a laminated stator yoke of a flat motor for achieving an eddy current reduction that improves the efficiency of a motor by reducing the eddy current by forming a stator yoke in a flat motor. Video cameras, camcorders, etc., information devices such as a hard disk drive and a PROFICAT DISK drive are equipped with flat motors. In a typical flat-type motor, a stator of a thin plate and a rotor are positioned so as to face each other, and the yokes support the back surface thereof. The schematic structure of such a flat motor will be described with reference to Fig. 1 is a schematic configuration diagram of a general flat-type motor. A conventional single-piece type motor includes a stator 10 fixed to a case (not shown) and a rotor 20 rotated by a striking force of the stator 10. The rotor (20) has a magnet (21) at a portion facing the stator (10). The back surface of the magnet 21 is attached to the rotor yoke 22 and is held and rotated integrally. The coil 11 faces the magnet 21 with a predetermined distance therebetween, and the stator yoke 12 sees the backside thereof. A PCB 13 is interposed between the stator yoke 12 and the coil 11 to control the rotation of the rotor 20 by applying a driving current to the coil 11. In the center portion of the stator yoke 12, a rotary shaft 30 is also penetrated and inserted into rotary material kehings 31. As a result, the rotor yoke 22 is fixed to the end of the rotating shaft 30. Therefore, the rotary shaft 30 is rotated by the rotational force of the rotor 20. FIG. 2 is a structural view showing a coil and a magnet for forming a correspondingly-generated magnetic force in FIG. 1, and FIG. 3 is a structural view of a general stator yoke. As shown in Fig. 2A, the magnets 21 are arranged in the circumferential direction with S poles and N poles alternating with each other. A coil 11 is disposed in the corresponding stator. As shown in FIG. 2B, the coil 11 is constructed by attaching coiled coils to the PCB 13 in a circumferential direction. The coils 11 are wound around the magnetic poles of the magnet 21. After passing through a magnetic flux generated from a certain magnetic pole of the corresponding magnet 21, each coil passes through a neighboring coil through a stator yoke 12 and flows to a neighboring magnetic pole of the corresponding magnet 21. At this time, when a current is applied to the magnet coil 11, a magnetic flux generated in each coil generates a magnetic flux, attracting force and repulsive force of the magnet to rotate the rotor. Therefore, the rotor composed of the magnet and the rotor yoke rotates to rotate the rotating shaft. FIG. 3A is a plan view of a stator yoke, wherein a dotted ellipse represents a path of a secondary magnetic flux. FIG. 3B is a half sectional view seen from the front of FIG. 3A. However, in such a conventional motor, an eddy current is generated when the magnetic flux passes through the stator yoke to generate a secondary magnetic flux. The stator yoke attempts to rotate along the rotor by this secondary flux.

However, if it is fixed to the case, its rotational force acts as a repulsive force, and current consumption increases. In addition, the driving efficiency is also reduced. Particularly, in the conventional motor, since the stator yoke is made of one cylindrical piece, the secondary magnetic flux draws a large elliptic path as shown in FIG. 3A, and the repulsive force generated thereby causes a decrease in current consumption and driving efficiency Big. SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a stacked-type stator yoke for a flat motor in which eddy currents generated in a stator yoke are reduced to a dim state,

1 is a schematic structural view of a general flat motor,

FIG. 2 is a structural view showing a coil and a magnet for forming a correspondingly-generated magnetic force in FIG. 1;

3 is a structural view of a general stator yoke,

4 is a structural view of a swath yoke according to the present invention;

Description of the Related Art [0002]

10: stator 11: coil

12: Data Data York 13:

20: rotor 21: magnet

22: rotor yoke 30: rotating shaft

31: bearing 40: stator yoke

41:

In order to solve such a problem, according to the present invention, there is provided a stator having a coil fixed to a case in a flat-type motor and rotatably driving the rotor by a mutual exertion force with a magnet, A coil is seated and supported, and an annular thin cylindrical body is laminated on a coaxial axis in a plurality of radial directions, thereby achieving the reduction of eddy current by a lapping type data yoke of a flat motor. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 4 is a structural view of a stator yoke according to the present invention, in which FIG. 4A is a plan view and FIG. 4B is a half sectional view viewed from the front. As shown in the figure, the present stator yoke 40 is formed by laminating annular thin plate cylindrical pieces 41 in the radial direction coaxially. Therefore, when passing through the magnetic flux, an eddy current is generated for each thin plate cylindrical piece 41, so that the generated secondary flux is also reduced. That is, as shown by an ellipse dotted line in FIG. 4A, it can be clearly seen that the secondary magnetic flux has a very small secondary magnetic flux path due to the eddy current generated in the conventional stator yoke described above, have. As a result, the magnetic flux becomes minute and the driving efficiency increases due to the reduction of the repulsive force contrary to the driving force.

As described above, according to the present invention, the redundant-type data yoke of the flat-type motor in which the eddy-current reduction according to the present invention has the coils of the annular thin plate cylinder coaxially arranged in the radial direction reduces the generation of the eddy current, And the driving efficiency is also increased due to the reduction of the repulsive force.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a flat motor in which a stator yoke is integrally formed by stacking ring-shaped thin cylindrical pieces with coaxial radius eaves to reduce eddy currents generated in a stator yoke to a dim state, Thereby providing a stacked stator yoke.

Claims (2)

A stator having a coil fixed to a case in a flat-type motor and rotatably driving the rotor by a mutual exertion force with a magnet, characterized in that the coil is seated and supported on one side of the coil opposite to the magnet, Are stacked in a plurality of radial directions on a coaxial plane, and the eddy currents are reduced. 2. The stacked type data yoke according to claim 1, wherein the stator yoke is less likely to generate an eddy current as the radius echo width of the thin web body decreases. ※ Note: It is disclosed by the contents of the first application.