JP3504827B2 - Axial air fan motor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axial gap type fan motor used for information equipment or power supply devices. 2. Description of the Related Art FIG. 5 shows a configuration of a conventional fan motor. FIG. 5 is a sectional view of a main part of the axial gap type fan motor. In FIG. 5, two ball bearings 2 arranged in the axial direction with respect to the shaft 21 are shown.
2 made of a synthetic resin also serving as a bearing holder via
An air-core coil 25 is mounted on the frame 23 and forms a stator S. In addition, a disc-shaped rotor yoke 26 is provided with a burring process at the center thereof to hold one end 21a of the shaft 21, and an inner surface of the rotor yoke 26 is provided with a predetermined gap through an air-core coil 25. The field magnet 27 is attached as described above, and constitutes the rotor R. Further, in the rotor R, a plurality of impellers 28 are provided on the outer periphery of the yoke 26 at equal intervals. In order to efficiently form a magnetic circuit by the field magnet 27, a yoke 29 is mounted between the frame 23 and the air-core coil 25 together with a circuit board. Reference numeral 30 denotes an electronic component mounted on the circuit board, and the frame 23 is resin-molded so as to cover the outer periphery of the turning space of the impeller 28. [0005] However, in the above-described configuration, startability becomes a problem. That is, since the rotor cannot be started due to the positional relationship between the rotor R and the stator S and a dead point has occurred, if the rotor is stopped at this position, the rotor R is no longer started at the next power supply. I couldn't let it. Therefore, it is necessary to separately provide a part for intentionally regulating the stop position of the rotor R on the circuit board or the yoke. For example, a component having magnetic attraction / repulsion is attached, and the position of attraction with the field magnet arranged on the rotor R is intentionally shifted in a predetermined rotation direction. In this case, This leads to an increase in the number of parts, which leads to an increase in man-hours, which not only impairs productivity but also increases costs. The same can be said for a fixed shaft type fan motor. Therefore, the present invention solves the above-mentioned problem and can start the motor with a simple structure without fail, thereby reducing the cost and the cost of the fan motor without impairing the productivity. To provide. According to the present invention, there is provided a rotor having a plurality of impellers and a NS-magnetized field magnet;
An axial gap type fan motor comprising a stator having an armature coil mounted on a frame through a predetermined gap in the rotor, the stator having a yoke for receiving a magnetic field of the field magnet. In the above,
The frame is formed by pressing a metal plate into the yoke,
Bearing part, which has a shaft for rotatably supporting the rotor,
A cover for covering the outer periphery of the swirling space of the impeller is integrally formed, and a position regulating means for stopping the rotor at a predetermined position is formed on the yoke by the metal plate.
Thus be those that are made, it is possible to prevent an increase in motor parts, so need not increase even the number of assembling steps, productivity without impairing, cost inexpensive without high cost A fan motor can be realized. Moreover,
Since this position regulating means only needs to have a simple structure for pressing the yoke, it can be processed simultaneously on the mold, and the labor for the processing can be saved. DETAILED DESCRIPTION OF THE INVENTION An axial gap type fan motor according to the present invention has a rotor having a plurality of impellers and an NS-magnetized field magnet, and a rotor provided on a frame through a predetermined gap. A stator having an armature coil mounted thereon, wherein the stator is an axial air-gap type fan motor including a yoke for receiving a magnetic field of the field magnet, wherein the stator is integrally formed with the yoke. And a position restricting means for stopping the rotor at a predetermined position. The position restricting means forms at least the frame by pressing a metal plate, uses a part of the frame as the yoke, and projects a part of the yoke toward the rotor. It is preferable that the rising portion is formed by the following method. Preferably, the position regulating means forms at least the frame by pressing a metal plate, and a part of the frame also serves as the yoke, and is preferably a recess provided in a part of the yoke. is there. FIG. 1 is a longitudinal sectional view of an essential part of an axial gap type fan motor according to an embodiment of the present invention, and FIG.
FIG. 3 is a cross-sectional view of a main part of the axial gap type fan motor in FIG. FIG. 3 is a diagram showing a frame formed by press working in the present invention. That is, in FIGS. 1 and 2, a frame 3 made of a metal plate also serving as a bearing holder is disposed via two ball bearings 2 disposed in the axial direction with respect to the shaft 1. The coil 5 is mounted, and constitutes the stator S. Further, the disk-shaped rotor yoke 6 is subjected to a burring process at a central portion thereof in order to hold one end 1a of the shaft 1, and an inner surface of the rotor yoke 6 is provided with a predetermined gap with the air-core coil 5. The field magnet 7 is attached as described above, and constitutes the rotor R.
Further, the rotor R is provided with a plurality of impellers 8 at equal intervals on the outer periphery of the yoke 6. Reference numeral 9 denotes a circuit board, on which various electronic components 10 are mounted, and terminals of the air-core coil 5 are connected to a circuit pattern formed on the circuit board 9. In the present embodiment, the rotor yoke 6 is formed in a disk shape by punching out an iron plate or the like made of a magnetic material, and the impeller 8 simultaneously punched out around its outer periphery is bent and raised. And a rotor / yoke 6 and an impeller 8 integrated to form a yoke / impeller. As shown in FIG. 3, the frame 3 is also pressed by pressing a metal plate, in this case, a magnetic plate, and then a flat plate made of a magnetic material is first drawn to form a bearing on the inner peripheral surface. The bearing 3a to be formed and the cover 3c covering the outer periphery of the turning space of the impeller 8 are formed, and then punching is performed to form the yoke 3b and the mounting portion 3d for mounting to the equipment and the like. In addition, 3
Reference numeral e denotes four stay portions which are integrally formed by connecting the yoke portion 3b and the cover portion 3c. The stay portion 3e has a projection 33e formed at one of the stay portions, as shown in FIG. As described above, by passing the lead wire 11 through this portion and then bending the protrusion 33e inward, the lead wire 11 can be fixed to the stay portion 3e. As shown in FIG. 1, the stator R is composed of two air-core coils having a 60-degree open angle at 120-degree intervals, which are displaced on the circumference. Then, similarly to the above embodiment, the thickness of the motor can be reduced by placing the circuit component 10 in the space formed on the opposite side of the stator R. In this case, if the field magnet 7 arranged on the rotor R is magnetized with six poles at a magnetization opening angle of 60 °, the output of the Hall element switches every 60 ° rotation, and the single-phase operation is performed. Full-wave driving becomes possible. Here, as shown in FIG. 2 or FIG.
Reference numeral 3f denotes a rising portion integrally formed with the yoke 3b by cutting out a part of the yoke 3b and raising this portion, and is formed at two places on the circumference. The armature coil 5 sets the stop position of the rotor R by the rising portion 3f.
The stop position of the rotor R is intentionally restricted by being shifted in the rotational direction by about 10 ° with respect to the reference position (dead point). By doing so, the dead point of the rotor R can be eliminated, and the rotor R can be surely started. As shown in FIG. 4, the yoke 3b may be provided with a concave portion 3g instead of the rising portion 3f. In this case, a hole may be formed by piercing a part of the yoke 3b, or a bag may be formed by pressing. In this way, if the yoke 3b is left in a portion where the magnetic driving force of the armature coil works, and the recess 3g is formed at least in a portion other than the portion, the stop position of the rotor R is intended similarly to the above. And the dead point of the rotor R can be eliminated. The present invention is not limited to the above embodiment, but can be implemented with appropriate modifications without departing from the gist of the present invention. For example, in the above embodiment, the circuit board is mounted on the back yoke portion and the air core coil and the electronic component are mounted on the circuit board in detail. However, the present invention is not limited to this. With this configuration, the circuit board can also be used as a yoke, and a further reduction in thickness can be expected. In the above embodiment, the shaft rotary type has been described in detail. As described above, according to the present invention, the stator is provided integrally with the yoke and provided with position regulating means for stopping the rotor at a predetermined position. Since the rising portion and the concave portion are formed as the position restricting means, the stop position of the rotor can be restricted with a simple structure to eliminate the dead point of the rotor, and the rotor can be reliably started. Further, the above configuration can prevent an increase in the number of parts of the motor, and does not require an increase in the number of assembly steps. Can be realized. Moreover,
Since this position regulating means only needs to have a simple structure for pressing the yoke, it can be processed simultaneously on the mold, and the labor for the processing can be saved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a main part of an axial gap type fan motor according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a main part of the axial gap type fan motor in FIG. 1; FIG. 3 is a diagram showing an example of a frame formed by press working in the present invention. FIG. 4 is a diagram showing another example of a frame formed by press working in the present invention. FIG. 5 is a sectional view of a main part of a conventional fan motor. [Description of Signs] 1,21 {shaft 3, 23} frame 3b, 29 {yoke 3f} rising part 3g {recess R} rotor S} stator

Continuation of the front page (58) Fields investigated (Int. Cl. ⁷ , DB name) H02K 1/12 F04D 29/44 H02K 21/24 H02K 29/00 H02P 3/00

Claims (1)

(57) [Claim 1] A rotor having a plurality of impellers and a NS-magnetized field magnet, and an armature coil mounted on the frame via a predetermined gap in the rotor. A stator having a yoke for receiving the magnetic field of the field magnet, wherein the frame is formed by pressing a metal plate.
The yoke and the rotor are rotatably supported by processing
Bearing section for arranging the rotating shaft, outer periphery of the turning space of the impeller
Cover part covering is integrally formed, wherein the position regulating means for stopping said rotor at a predetermined position on the yoke
An axial gap type fan motor formed on the yoke by a metal plate .