JP2970764B2 - motor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a motor, and more particularly, to a motor having an exciting coil in a stator.

[Related Art] Conventionally, various motors are known, such as various motors using an electromagnet or a permanent magnet for a stator and a rotor, a stator having an exciting coil, and a hysteresis motor using a rotor having a hysteresis ring.

Motors are used in a variety of situations and require different characteristics.

[Problem to be Solved by the Invention] There is a demand for a motor having novel features that have never been seen before.

For example, there is a demand for a motor having a simple configuration suitable for miniaturization and a motor that can be reliably started in a predetermined direction.

An object of the present invention is to provide a motor having a novel configuration.

Another object of the present invention is to provide a motor having a simple configuration suitable for miniaturization.

Another object of the present invention is to provide a motor having a simple configuration that can be reliably started in a predetermined direction and is suitable for downsizing.

[Means for solving the problem]

The motor according to the present invention includes a stator having a plurality of excitation coils capable of generating a rotating magnetic field, and a rotor coaxially rotatable in the rotating magnetic field, and a ring-shaped member formed of a magnetic material. The ring-shaped member has a periodic notch, and the size of the notch changes with respect to the rotation direction of the rotor.

Another motor according to the present invention includes a stator having a plurality of exciting coils capable of generating a rotating magnetic field, and a rotor coaxially rotatable in the rotating magnetic field, wherein the ring is formed of a magnetic material. The ring-shaped member has a periodic notch, and the rotor has a different magnetic resistance between a right side portion and a left side portion of the notch when the rotating shaft of the rotor is set upright. And

[Operation] When a ring-shaped member made of a magnetic material is arranged in the rotating magnetic field formed by the exciting coil of the stator, a magnetic circuit is formed through the ring-shaped member. Since a cyclic notch is formed in the ring-shaped member, the magnetic characteristics of the ring-shaped member periodically change. Therefore, the action of the rotating magnetic field on the ring-shaped member varies in intensity locally, and rotates the ring-shaped member according to the rotating magnetic field.

Further, when the size of the notch changes with respect to the rotation direction of the rotor, when a magnetic field is formed at the time of starting, the force acting differs depending on the direction of the notch, and the ring-shaped member is started only in a predetermined direction. The same applies to the case where the right side and the left side of the notch have different magnetoresistance.

Embodiment FIGS. 1A, 1B and 1C schematically show a motor according to an embodiment of the present invention.

FIG. 1A is a schematic plan view showing the configuration of the motor. The stator 12 having the exciting coil 11 can form a rotating magnetic field in the vicinity thereof. The rotor 14 is arranged in the rotating magnetic field. Note that the rotor 14 is rotatably held around a shaft 16.

The rotor 14 has a notch 18 as shown in FIG.
Is provided. The notch 18 is provided periodically along the circumferential direction of the rotor 14. The shape of the notch can be variously changed as described later.

The interaction between the rotating magnetic field generated by the stator 12 and the rotor 14 will be described with reference to FIG. Since the rotor 14 is provided with the notch 18, a portion without the notch 18 is provided.
The magnetic properties of the notch 19 and the notched portion 18 are different. When considering a magnetic circuit, the portion of the notch 18 has a high magnetic resistance, and the portion 19 without the notch has a low magnetic resistance. As shown, when an N pole and an S pole are formed near the rotor 14, a magnetic circuit is formed via the rotor 14, but this magnetic circuit is deformed by the presence of the notch 18. The magnetic circuit is stable when its magnetic resistance is the smallest, and a force acts in the direction of decreasing the magnetic resistance. In the case shown, N
Due to the presence of the notch 18 near the pole, the magnetic circuit is formed so as to be biased toward the non-notched portion 19, and its magnetic resistance is relatively high. A force for rotating the rotor 14 in the direction of the arrow acts to lower the magnetic resistance. When the rotor 14 rotates and the notched portion 19 joins the north and south poles, the magnetic resistance decreases and attempts to stabilize. However, since the magnetic field formed by the stator 12 rotates, the rotor 14 rotates according to the rotating magnetic field.

If the shape of the notch 18 is symmetrical with respect to the axis of the shaft 16 as shown in FIG. 1 (B), the rotor may reversely rotate at startup.

2A and 2B show a structure suitable for preventing reverse rotation.

FIG. 2A shows a case where the rotor 14 has a triangular notch 18a. As described above, when the size of the notch changes with respect to the rotation direction, a difference is generated between the force acting on the right side portion and the force acting on the left side portion of the notch, which is suitable for rotating in a predetermined direction. Although the shape of the triangle is excited, any shape other than the triangle may be used as long as there is a difference between the right side and the left side.

FIG. 2 (B) shows that although the shape of the notch 18 itself is symmetrical, the rotor 14 further includes a load-
Are formed, and the magnetic characteristics are asymmetric. That is, in the illustrated configuration, the notch 18
A protrusion 20 made of a magnetic material is added to the left side of the to reduce the magnetic resistance. As a result, a difference occurs in the magnetic resistance between the left portion and the right portion of the opening 18, and rotation in a predetermined direction is guaranteed. Although the case where the projection is added is illustrated, the difference may be provided by, for example, reducing the thickness, changing the distance in the radial direction, changing the material, or the like.

Further, a ferromagnetic material having hysteresis characteristics can be used for the ring member of the rotor 14.

When a ferromagnetic material having a hysteresis characteristic as shown in FIG. 3 is used, the uncut portion 19 of the rotor 14 (see FIG. 1C) operates similarly to the rotor of the hysteresis motor. That is, the change in the rotating magnetic field H and the change in the magnetization are not proportional, and an energy corresponding to the illustrated area in the loop, that is, a force is generated. In this case, the characteristics of the hysteresis motor and the characteristics due to the above-described spatially distributed magnetic characteristics are added to form a motor having new characteristics.

Although the present invention has been described with reference to the embodiments, the present invention is not limited thereto. For example, it will be apparent to those skilled in the art that various modifications, improvements, combinations, and the like can be made.

[Effects of the Invention] As described above, according to the present invention, a motor having novel features is realized.

 Since it has a simple configuration, it is suitable for miniaturization.

Further, by adjusting the symmetry of the opening, a motor that prevents reverse rotation is provided.

[Brief description of the drawings]

1A, 1B, and 1C are views for explaining a motor according to an embodiment of the present invention. FIG. 1A is a plan view showing a schematic configuration, and FIG. 1) is a partial side view showing the configuration of the rotor, FIG. 1 (C) is a schematic diagram for explaining a magnetic circuit, and FIGS. 2 (A) and 2 (B) are perspective views showing an example of a structure for preventing reverse rotation of the rotor. FIG. 3 is a graph showing hysteresis characteristics when a hysteresis material is used. In the figure, 11 ... exciting coil 12 ... stator 14 ... rotor 16 ... shaft 18 ... notch 19 ... part without notch 20 ... projection

Claims (1)

(57) [Claims] 1. A stator having a plurality of exciting coils capable of generating a rotating magnetic field, and a rotor coaxially rotatable in the rotating magnetic field,
A ring-shaped member formed of a magnetic material, wherein the ring-shaped member has a periodic notch, and each of the notches is shaped such that its size changes with respect to the rotation direction of the rotor; A motor having a rotor and.