JP2007288826A - Rotary machine utilizing uneven magnetic flux distribution - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary machine wherein that the rotary machine cannot rotate due to friction between a stator and a rotor is eliminated, when the air gap between the stator and the rotor is narrowed, in order to enhance rotary performance, and at the same time, rotative direction is determined by utilizing uneven magnetic flux distribution. <P>SOLUTION: The rotary machine utilizing uneven magnetic flux distribution is constituted, such that a disc magnetic body stator to which an electromagnet is attached and a disc magnetic body rotor, to which a permanent magnet is attached, are arranged concentrically, and the rotative direction is determined, by varying the amount of magnetic flux from the pole face of the electromagnet by the position of the pole face. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention is directed to an electric motor that converts electric energy into kinetic energy and a generator that converts kinetic energy into electric energy, and relates to a rotating machine that uses an electromagnet and a permanent magnet.

  There are many types and types of electric motors, and they are used in a wide range of fields. Some motors can also be used as generators, such as DC motors. Electric motors and generators are handled as rotating machines, and in recent years it has become important to increase the energy conversion efficiency of rotating machines. This is from the viewpoint of protecting the global environment through energy savings. Conventionally, an induction motor and a synchronous motor using a rotating magnetic field generated by a three-phase alternating current, and an induction motor having a mechanism for generating currents having different phases by a capacitor from a single-phase alternating current have been put to practical use. In addition, there are motors with commutators. These motors are complicated in structure and have defects such as requiring a complicated power source. In terms of structure, a combination of a cylindrical rotor and a cylindrical stator having a cylindrical space for mounting the cylindrical rotor is the mainstream. This is because the energy conversion efficiency is high to some extent and reliability is established. However, the gap between the cylindrical stator and the cylindrical rotor is determined in consideration of machining accuracy, thermal deformation of the cylindrical stator and the cylindrical rotor, and wear of the bearing. Has its limits. For this reason, since the magnetic resistance related to the gap between the cylindrical stator and the cylindrical rotor does not become low, there is a limit in improving the rotational performance. Accordingly, it is a top priority to reduce the magnetic resistance by reducing the gap. For ease of explanation, referring to FIG. 4 showing a general electric motor 20, the electric motor 20 includes an N-pole permanent magnet 21, an S-pole permanent magnet 22, and a rotor 24, and the rotor 24 further includes a shaft 25. 3 is composed of three electromagnets 26 and a commutator 27. Fig. 4 shows the case where the rotor has three poles, but since the number of poles is generally large, the rotor has a cylindrical shape, and the hollow portion of the stator combined with this rotor also has a cylindrical shape. It has become. Therefore, although FIG. 4 is not cylindrical, the operation principle will be described assuming that it is cylindrical. In FIG. 4, when the magnetic pole 23-1 is designed to be the south pole, the magnetic pole 23-1 is the south pole permanent. Upon receiving a repulsive force from the magnet 22 and simultaneously receiving an attractive force from the N-pole permanent magnet 21, the rotor rotates in the clockwise direction. When the magnetic pole 23-2 passes through the N-pole permanent magnet 21 by this rotation and the magnetic pole 23-2 is magnetized to the N-pole, the magnetic pole 23-2 attracts the repulsive force from the N-pole permanent magnet 21 and the S-pole permanent magnet 22. Continue to rotate clockwise with force. When the magnetic pole 23-2 obtains the rotational force, the magnetization state of the magnetic pole 23-1 is canceled. Such an operation is repeated to cancel the magnetization state of the magnetic pole 23-2. However, when the magnetic pole 23-2 passes through the S-pole permanent magnet 22, this time the magnet is magnetized to the S-pole and the above operation continues. Done.

Next, in FIG. 4, the gap between the magnetic pole 23 and the permanent magnets 21 and 22 needs a sufficient margin for shape expansion / contraction due to temperature change, wear of the bearing, machining accuracy, and the like. The gap between the magnets 21 and 22 cannot be made sufficiently small. Further, if foreign matter is mixed between the magnetic pole 23 and the permanent magnets 21 and 22, a serious failure may be caused. This increases the burden of maintenance such as bearing wear inspection and rotor and stator dimension confirmation.

  For this reason, it is difficult to reduce the gap between the inner cylindrical stator and the cylindrical rotor. This is because the shape expansion and contraction of the rotor directly affects the stator, and as a result, there is a risk that the rotor contacts the stator. As an improvement measure, a disk type stator and a disk type rotor are used instead of the cylindrical type rotor and the cylindrical type stator. This is because even if there is expansion and contraction in the diameter direction of the disk of the disk type rotor, the disk type rotor does not come into contact with the disk type stator to inhibit rotation. Further, since the shape expansion and contraction in the thickness direction of the disk type rotor can be absorbed by the play of the shaft, the gap between the disk type stator and the disk type rotor can be made extremely small. As a result, the resistance of the magnetic circuit is lowered, the rotational performance is improved, and there is no danger that the rotor contacts the stator, which is advantageous in terms of safety.

Further, referring to FIG. 4, since the commutator 27 is used to control the current flowing through the three electromagnets 26, the structure is complicated, and further, the reliability is lowered.

In FIG. 4, the permanent magnets 21 and 22 can be used in an alternating current by replacing them with electromagnets. However, it is difficult to solve the problem of structural complexity and reliability degradation.
Japanese Patent Laid-Open No. 11-98720

The problem to be solved is that since the gap between the cylindrical rotor and the cylindrical stator cannot be made extremely small, the resistance of the magnetic circuit is not lowered, so that the rotational performance is not improved. Therefore, the problem to be solved by the invention is to reduce the gap between the rotor and the stator and to prevent the rotation performance from being affected by the shape expansion and contraction due to the temperature change of the stator and the rotor. Realizes an electric motor that operates with AC and has a simple structure and high reliability.

In order to solve the above problems, a rotating machine according to the present invention has a disk magnetic material stator and a disk magnetic material rotor that are concentrically opposed to each other. And the gap between them is extremely small. As a result, the magnetic resistance of the magnetic circuit formed by the disk magnetic body stator and the disk magnetic body rotor is reduced, and it is avoided that the rotation becomes impossible due to the contact between the stator and the rotor.

From the viewpoint of simplifying the structure, a disk magnetic stator having a plurality of electromagnets and a disk magnetic rotor having a permanent magnet are concentrically opposed to each other, and the magnetic flux from the magnetic pole surface of the electromagnet The use of a commutator is avoided by determining the direction of rotation by changing the amount according to the position of the pole face.

The rotating machine of the present invention configured as described above can achieve high rotation performance at low power consumption due to low magnetic resistance. Furthermore, even if the shape of the stator and rotor due to temperature changes expands and contracts, the performance of the rotating machine is not affected, and since the commutator is not used, the concept is simplified and high reliability is obtained. Therefore, maintenance burdens such as bearing wear inspection and rotor and stator dimension confirmation are reduced.

By maintaining good parallelism of both disks so as not to hinder the rotation of the disk magnetic rotor even if the gap between the disk magnetic stator and the disk magnetic rotor is narrowed. is there. Under the condition that the rotational force of the disc magnetic rotor is sufficiently transmitted to the mounting shaft, a certain amount of play between the mounting shaft and the mounting shaft can alleviate the machining accuracy and bearing wear conditions. Preferred embodiment above. In order to reduce the magnetic resistance of the magnetic circuit, the gap between the disk magnetic stator and the disk magnetic rotor must be narrowed. Making it larger than the gap at the center of the plate is effective in reducing the overall magnetoresistance.

Embodiments will be described with reference to the drawings. FIG. 1 is a diagram showing a rotating machine using a disk magnetic rotor according to the present invention. A disk magnetic rotor 1 mounted on a shaft 6, a plurality of electromagnets 3, a disk magnetic stator 2, and a blanket. It is composed of four. The bearings 6 and 8 are provided at the centers of the blanket 4 and the disc magnetic stator 2, respectively. The magnetic circuit 7 will now be described. As indicated by the dotted dotted line, the magnetic flux generated by the electromagnet 3 passes through the electromagnet magnetic pole 9, the disk magnetic rotor 1, the shaft 5, and the disk magnetic stator 2 to the electromagnet 3. Return. In order to increase the magnetic flux passing through the magnetic circuit 7 and improve the rotational performance, the magnetic resistance of the magnetic circuit 7 may be lowered. For this purpose, it is effective to narrow the gap between the disk magnetic rotor 1 and the electromagnet magnetic pole 9. Further, in order to absorb the shape expansion and contraction in the thickness direction of the disk magnetic rotor 1 and the disk magnetic stator 2 due to temperature changes, a play is provided on the shaft 6.

Next, the operation principle will be described with reference to FIG. 2. FIGS. 2 (a) and 2 (b) are a sectional view taken along line II and a sectional view taken along line II-II in FIG. 1, respectively. 1 and 2, the same reference numerals are used for the same parts and members. In FIG. 2A, six electromagnets 3 (n ₁ -n ₆ ) are mounted on the disk magnetic stator 2, and these electromagnets are simultaneously driven by alternating current. FIG. 2 (b) shows a disk magnetic rotor 1 with six permanent magnets 10 mounted thereon. Three permanent magnets having the same magnetization direction are alternately arranged with three permanent magnets having different magnetization directions. The FIG. 2C is a cross-sectional view taken along the line III-III and shows a case where the centers of the electromagnet n ₁ and the permanent magnet S ₁ coincide. When the magnetic pole of the electromagnet n ₁ is magnetized to the N pole, the attractive force of n ₁ and S ₁ is maximized, but no rotational force acts on S ₁ . However, if the center of the electromagnet n ₁ and the permanent magnet S ₁ as shown in FIG. 2 (c) do not coincide, because the gap between the electromagnet n ₁ and the permanent magnet S ₁ is a non-uniform, The magnetic flux density in the small gap portion is increased, and the permanent magnet S ₁ is attracted to the electromagnet n ₁ . As a result, the permanent magnetic pole S ₁ rotates clockwise in FIG. 2 (a), the electromagnets n ₁ repulsive force is generated between the n ₁ and S ₁ when changing from the N pole to the S pole, S ₁ shown in FIG. 2 (b) as a result rotates clockwise . Explaining this reason, the repulsive force acting between the electromagnet n ₁ and the permanent magnet S ₁ is reduced, that is, S ₁ rotates in the clockwise direction.

As is clear from the above description, the attractive force and repulsive force acting between n ₁ and S ₁ is the direction in which the magnetic disk rotor 1 rotates clockwise, that is, the amount of magnetic flux from the magnetic pole surface of the electromagnet increases. Rotate to. As described above, in the case of the conventional cylindrical type, it is difficult to narrow the gap between the stator and the rotor. Further, the foreign matter mixed in the gap is subjected to centrifugal force and sticks to the stator. It is difficult to drive out. On the other hand, in the disc type, the centrifugal force to the foreign substance acts to drive the foreign substance out, so the failure probability is low. Since the rotating machine according to the present invention does not require a commutator and a three-phase alternating current, a rotating machine with a simple structure and high reliability can be provided.

  Next, another embodiment will be described with reference to FIG. The same reference numerals will be used where they have the same purpose and function as in FIG. Another method for changing the amount of magnetic flux from the magnetic pole surface of the electromagnet mounted on the disc magnetic rotor 2 is to make the magnetic pole wedge-shaped as shown in FIG. The rotating machine according to this embodiment has the same advantages as the first embodiment.

It is a figure which shows the rotary machine using the disk magnetic body rotor by the Example of this invention. (a) And (b), respectively, is the II sectional view taken on the line of FIG. 1, and the II-II sectional view taken on the line. (c) And (d) is the III-III arrow directional cross-sectional view of FIG. It is a figure which shows the disk magnetic body rotor by other Example of this invention. It is a figure which shows the conventional electric motor.

Explanation of symbols

1 is a disk magnetic rotor 2 is a disk magnetic stator 3 is an electromagnet 4 is a blanket 5 is a shaft 6 and 8 is a bearing 7 is a magnetic circuit 9 is an electromagnetic pole.
10 is a permanent magnet
20 is a DC motor
21 is an N pole permanent magnet
22 is S pole permanent magnet
23 (23-1, 23-2, 23-3) are electromagnetic poles
24 is a rotor
25 is the axis
26 is an electromagnet
27 is a commutator

Claims (2)

A disk magnetic stator with a plurality of electromagnets and a disk magnetic rotor with a permanent magnet are concentrically opposed, and the amount of magnetic flux from the magnetic pole surface of the electromagnet varies depending on the position of the magnetic pole surface. A rotating machine that uses a non-uniform magnetic flux distribution to determine the direction of rotation. A cylindrical rotor with a permanent magnet is attached to a hollow cylindrical stator with a plurality of electromagnets, and the amount of magnetic flux from the magnetic pole surface of the electromagnet is changed according to the position of the magnetic pole surface to change the direction of rotation. A rotating machine that uses a non-uniform magnetic flux distribution.

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