JPH0433551A - Motor using permanent magnet - Google Patents

Abstract

PURPOSE:To alleviate necessity of a yoke and to simplify a structure by alternately inverting the polarities of poles of a plurality of permanent magnets, arranging them in series, and employing the magnets as magnetic path forming parts. CONSTITUTION:A plurality of permanent magnets 1a-1d are disposed in series, and the polarities of the adjacent magnets are inverted and arranged. That is, N-pole of the magnet 1a and N-pole of the adjacent magnet 1b are opposed to form a composite N-pole, and similarly S-pole of the magnet 1b and S-pole of the magnet 1c are opposed to form a composite S-pole. Similarly, the opposed parts of the magnets 1e, 1d form an N-pole, and thus N-pole, S-pole, N-pole,..., are alternately formed. lf armature coils 15 are disposed oppositely to the plurality of the poles formed in this manner, an effective magnetic circuit can be formed, and a magnetic flux is not almost generated at the opposite side of an armature, and hence it is not always necessary to provide a yoke at the opposite side of the armature.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a motor, and particularly to a motor using permanent magnets.

[Conventional technology] There are various types of motors using permanent magnets.

A magnetic circuit containing permanent magnets is formed within the motor, and the motor is driven by interaction with a magnetic field that is generated and controlled by passing current through the coil.

As an example that does not have any limiting meaning, see Figure 2 (A
>, (B) shows an example of an outer rotor type DC motor according to the prior art.

In FIG. 2(A), the rotor 1 has a cylindrical shape and is rotatably arranged surrounding the stator 2.

The rotor 1 has a cylindrical permanent magnet yoke 13 and a plurality of permanent magnets 11a, 11b, . Each permanent magnet is radially magnetized. Adjacent permanent magnets have reversed polarities so that S and N poles are alternately exposed on the inner peripheral surface. In the illustrated configuration, eight poles are arranged in stripes along the axial direction on the inner peripheral surface. The permanent magnet yoke 13 has permanent magnets 11a, 11. This is for forming an effective magnetic path by surrounding the externally exposed magnetic poles of b, .

The stator 2 has a plurality of armatures 12a, 12b, . The armature cores 14 are internally connected to each other and fixed on the shaft.

An example of the magnetic path formed in FIG. 2(B) is shown.

The N pole is exposed on the inner surface of the permanent magnet 11a, and the armature 12a
I am competing with S& is exposed on the inner surface of the adjacent permanent magnet 1.1b. Therefore, a magnetic path is formed from the inner surface of the permanent magnet 11a, passing through the armature 12a and the armature 12b via the gap, and reaching the inner surface of the permanent magnet 11b via the gap. This magnetic path passes from the outer surface of the permanent magnet 11b, passes through the permanent magnet yoke 13, reaches the outer surface of the permanent magnet 11a, and is closed.

If the yoke 1 is not provided, the magnetic poles on the outer surfaces of the permanent magnets 11a and 11b will be exposed to air with high magnetic resistance, making it impossible to form an effective magnetic circuit. It is therefore necessary to arrange a plurality of permanent magnets in a radial direction, with one side facing the armature and the other side being supplied by the yoke.

[Problems to be Solved by the Invention] As explained above, in the conventional motor using permanent magnets, the permanent magnets are arranged in the radial direction,
It was necessary to place a yoke on the opposite side of the coil. This requires no space and no parts.

The object of the invention is to save space and parts.
An object of the present invention is to provide a motor using permanent magnets.

[Means for Solving the Problems] The motor of the present invention has a rotor and a stator, and uses a plurality of permanent magnets in the rotor and the stator, and the plurality of permanent magnets alternately reverse polarity. The permanent magnets are arranged in series, and the poles of the same polarity of adjacent permanent magnets jointly constitute one magnetic pole.

[Operation] By arranging a plurality of permanent magnets in series, the magnetic poles are opposed to each other. The magnetic poles are not exposed as widely as in the past.

Furthermore, by arranging the plurality of permanent magnets with their polarities alternately reversed, magnetic poles of the same polarity face each other, forming one composite magnetic pole at that location. In this way, a plurality of magnetic poles are arranged in a serially arranged magnet row.

By arranging the armature coil so as to oppose the plurality of magnetic poles formed in this manner, an effective magnetic circuit can be formed. Since almost no magnetic flux can be generated on the opposite side of the armature, it is no longer necessary to provide a yoke on the opposite side of the armature. Further, when providing a yoke, a simpler structure is required compared to the conventional case.

[Embodiment] FIGS. 1A and 1B show a motor according to an embodiment of the present invention.

FIG. 1(A) is a schematic sectional view showing the configuration of an outer rotor type DC motor. rotor on the outside].

A stator 2 is arranged inside to constitute a DC motor. The rotor 1 includes a plurality of permanent magnets 1a, 1b, Ic, .
...has a loop shape arranged in series, and adjacent permanent magnets are arranged with reversed polarity. For example, permanent magnets 1a and 1b are arranged with their S poles facing each other, and permanent magnet 1b and IC are Nf! are placed facing each other. Therefore, the facing portion of permanent magnets 1a and 1b is S'
If1 is formed, and the opposing portions of permanent magnets 1b and 1c are made of Ni.

The stator 2 has a plurality of yokes, with slots formed between each yoke. In the illustrated configuration, 12 poles 9
The slot is shown. Note that an armature coil is wound around each yoke, but is not shown.

FIG. 1(B) is a conceptual diagram for explaining a magnetic path created by permanent magnets arranged in series with alternately reversed polarities. Permanent magnets 1a, 1b, 1c, and 1d are arranged in series, with magnetic poles facing each other. Here, N[i of the permanent magnet 1a and the N pole of the adjacent permanent magnet 1b face each other to form a composite N pole, and similarly, the S pole of the permanent magnet 1b and the S pole of the permanent magnet 1C face each other. Form a composite south pole. Similarly, the opposing parts of the permanent magnet IC and 1d form the N pole, and in this way, the N pole is alternately
i, Si, , Ni, . . . are formed. therefore,
Functionally, the Ni and S poles can be placed at positions facing the armature coil in the same way as when magnets are arranged in the radial direction. In this case, the magnetic field lines from the magnetic poles of the permanent magnet toward the armature travel from the armature to an adjacent armature, enter the adjacent magnetic pole of the permanent magnet from the adjacent armature, and then return through the permanent magnet.

Therefore, there is no need to intentionally provide a yoke on the outside of the permanent magnet. Therefore, in the configuration of FIG. 1(A), the rotor 1 made of permanent magnets is not provided with a yoke on its outer circumference.

By omitting the yoke, it is possible to form a motor with a compact configuration and a small number of parts.

Note that although a magnet with an arc-shaped cross section is illustrated, a rectangular parallelepiped-shaped magnet may also be used. Appropriate spacing may be provided between the magnets.

In addition, although a configuration with a stator on the inside and a rotor on the outside has been described, a configuration with a rotor on the inside and a stator on the outside,
It is also possible to arrange the rotor and stator at different positions on the axis so that they face each other in the axial direction. Also,
Although a configuration in which the rotor includes permanent magnets has been described, a configuration in which the stator includes permanent magnets and the rotor includes an armature may also be used. It can be widely applied to other motors using permanent magnets.

FIG. 3 shows a motor according to another embodiment. A cylindrical stator 3 is placed on the outside, and a rotor 4 is placed on the inside.
A yoke 5 is arranged on the outside.

The stator 3 includes a plurality of permanent magnets 3a, 3b, . . . arranged in a series loop. Adjacent permanent magnets have magnetic poles of the same polarity facing each other. As in the case of FIG. 1, the opposing magnetic poles form a composite magnetic pole.

The rotor 4 includes a plurality of armatures 4a, 4b, .

The armature coil is not shown. When the rotor 4 rotates, a magnetic path similar to that shown in FIG. 1(B) is formed. In the case of this embodiment, since the yoke 5 is arranged outside the permanent magnet, the magnetic flux also enters the yoke 5.

Note that the yoke 5 is connected to the permanent magnets 3a, 3b of the stator 3.
...do not necessarily have to be in close contact with each other. For example, the cases may be stacked and placed a certain distance apart.

Although the present invention has been described above along with examples, the present invention is not limited to these. Examples include various changes,
It will be obvious to those skilled in the art that improvements, combinations, etc. are possible.

[Effects of the Invention] As explained above, according to the present invention, by arranging a plurality of permanent magnets in series with their polarities alternately reversed, the permanent magnets are effectively used as magnetic path forming components, and the yoke is The need can be reduced.

Therefore, it is possible to construct a motor with a simple configuration and a simplified number of parts.

[Brief explanation of the drawing]

FIGS. 1(A) and 1(B) are diagrams for explaining a motor according to an embodiment of the present invention, FIG. 1(A) is a schematic cross-sectional view showing the configuration, and FIG. 1(B) is a magnetic FIGS. 2(A) and 2(B) are diagrams for explaining a conventional motor, and FIG. 2(A) is a schematic partial sectional view showing the configuration. FIG. 2(B) is a partial cross-sectional view showing magnetic path formation, and FIG. 3 is a schematic cross-sectional view for explaining a motor according to another embodiment of the present invention. In the figure: 1 Rotor 1a, 1b... Permanent magnet 2 Stator 2a, 2b... Yoke 3 Stator 4 Rotor 5 Yoke 11, a, 1 l b... 12 a, 1 2 b -... Permanent magnet armature Yoke armature core armature coil for permanent magnet

Claims (1)

[Claims] (1) A motor having a rotor and a stator and using a plurality of permanent magnets in the rotor or stator, the plurality of permanent magnets are arranged in series with their polarities alternately reversed, and adjacent permanent magnets are A motor using a permanent magnet, characterized in that poles of the same polarity work together to constitute one magnetic pole.