JP2001061243A - Structure of rotor and motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure of a rotor, capable of reducing the number of manufacturing processes and cost, and a motor. SOLUTION: A rotor 10 is provided with a rotor shaft 11, a spacer 12 and magnets 13. The spacer 12 is made of a metal, and its outward form is formed into an octagonal pillar type having outer surfaces 12b of the same number of edges as that of the product (i.e., P×m=8) of the number P(=8) of the magnetic poles of a motor and a division number m(=1) of unlike pole magnets sandwiched by the like pole magnets. Eight magnets 13 are arranged correspondingly to the respective outer surfaces 12b. Each of the magnets 13 is cut out from a cubic permanent magnet block member and is formed into a rectangular form whose long edge is in the axial direction of the rotor. Each of the magnets 13 is arranged on each of the outer surfaces 12b and stuck to the spacer 12 using adhesive agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric motor and a rotor for the electric motor, and more particularly to a structure of the rotor.

[0002]

2. Description of the Related Art In a rotating magnetic field type motor using a permanent magnet for a rotor, a permanent magnet is attached to the surface of the rotor. Many conventional rotor structures of this type have been proposed (for example, Japanese Utility Model Laid-Open No. 7-42548).

More specifically, as shown in FIG. 5, a rotor 50 has an outer shape of a spacer 51 formed in an arc shape, and an inner surface 52a of a plurality of permanent magnets 52 provided on an outer peripheral surface 51a of the spacer 51. Are also formed in an arc shape. At this time, the spacer 51 and the permanent magnet 52 are manufactured in separate manufacturing steps. For example, the permanent magnet 52 is manufactured in a manufacturing step as shown in FIG. That is, first, FIG.
A rectangular parallelepiped permanent magnet material 54 having a predetermined size as shown in FIG. 6B is cut out from the permanent magnet block 53 formed by pressing as shown in FIG. Then, the permanent magnet material 54 is processed into an arc-shaped permanent magnet 52 on both the inner and outer surfaces as shown in FIG.

[0004]

The curvature of the inner surface 52a of the permanent magnet 52 and the outer circumferential surface 5 of the spacer 51 are different.
1a do not match, the inner surface 52 of the permanent magnet 52
a and the outer peripheral surface 51 a of the spacer 51 are brought into close contact with each other by using a magnet fixing jig pin 55 to fix the magnet 52.
When the magnet 52 is held down by the spacer 51, the magnet 52 may be cracked or displaced. Therefore, the curvature of the inner surface 52 a of the permanent magnet 52 and the outer circumferential surface 51 of the spacer 51 may be reduced.
In order to make the curvature of "a" as close as possible, the inner surface 52a of the permanent magnet 52 and the outer peripheral surface of the spacer 51 need to be precisely polished in an arc shape. This not only requires time and effort, but also increases costs.

An object of the present invention is to provide a rotor structure capable of reducing the number of manufacturing steps and costs and an electric motor capable of achieving high output.

[0006]

Means for Solving the Problems To solve the above problems, the invention according to claim 1 has a rotating shaft, a spacer that rotates integrally with the rotating shaft, and an outer surface of the spacer. In the structure of the rotor including a plurality of magnets, the spacer is formed in a polygonal column shape having a plurality of outer surfaces, and each magnet attached to each outer surface has an axial square shape. The gist is that it is formed.

According to a second aspect of the present invention, in the structure of the rotor according to the first aspect, the number of sides constituting the outer shape of the spacer is the same as the number of magnetic poles of the electric motor. The gist is that it is the same as the product of the number of divisions.

[0008] The invention according to claim 3 is the invention according to claim 1 or 2.
In the structure of the rotor according to the above, the spacer,
The gist is that it is formed in a polygonal column shape having eight or more sides.

The invention described in claim 4 is the first to third aspects of the present invention.
In the electric motor having the rotor according to any one of the above, the subject matter is summarized. (Operation) According to the first and second aspects of the present invention, the magnet can be made by simply cutting the magnet from, for example, a cubic permanent magnet block directly into a rectangular parallelepiped. This eliminates the need and reduces the number of manufacturing steps and costs.

In addition, since each magnet is formed in the shape of a quadrangle in the axial direction, that is, both the spacer-side contact surface and the outer surface of each side of the spacer are formed in a plane, each magnet can be easily and reliably connected to each side of the spacer. Can be stuck to the outer surface of the magnet, and the displacement of each magnet can be prevented.

According to the invention described in claim 3, according to claim 1 of the present invention,
In addition to the effects of the inventions described in (2) and (3), when the mechanical gap between the rotor and the stator is fixed, the magnetic gap and the number of magnetic poles of the electric motor × the number of divisions of the different pole magnet sandwiched between the same poles Has an inversely proportional relationship. At this time, the spacer is formed in a polygonal column shape having eight or more sides. That is, since the product of the number of magnetic poles of the motor and the number of divisions of the different pole magnets interposed between the same poles is set to 8 or more, the magnetic gap can be reduced.

According to the invention described in claim 4, according to claim 1,
In addition to the effects of the inventions described in (1) to (3), it is possible to increase the output of the electric motor.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment in which the present invention is embodied in a rotating magnetic field type electric motor will be described below with reference to FIGS.

The rotor 10 of the present embodiment has a rotor shaft 11, a spacer 12, and a magnet 13. As shown in FIG. 1, the rotor shaft 11 is inserted through a through hole 12 a provided at the center of the spacer 12. That is, the rotor shaft 11 is integrated with the spacer 12.

The spacer 12 is made of metal, and its outer surface has the same number of sides as the product of the number P of magnetic poles of the motor and the number m of divisions of the different pole magnets sandwiched between the same poles (that is, P × m). 1
It is formed in an equilateral polygon having 2b. In the present embodiment, the number of magnetic poles P of the electric motor is set to 8, and the same pole (for example, N pole)
The spacer (12) is formed in an octagonal (P × m = 8) column shape with the number (division number) m of the different pole (S-pole) magnet interposed therebetween being one. The magnet 13 is arranged on the outer surface 12b of each side. 8 corresponding to the outer surface 12b of each side
The magnets 13 are provided.

Each magnet 13 is a permanent magnet, as shown in FIG.
(A) As shown in (b), it is cut out from a cubic permanent magnet block material 14 of a predetermined size,
It is made rectangular (when viewed from the 0 axis direction). That is,
The spacer-side contact surface 13a of each magnet 13 is flat. Then, each magnet 13 is arranged on each outer surface 12b, and is attached to the spacer 12 with an adhesive.

According to the rotor 10 of the present embodiment, the following features can be obtained. (1) In the present embodiment, the outer shape of the spacer 12 constituting the rotor 10 is formed in a regular polygon. Further, the magnet 13 attached to each outer surface 12b of the spacer 12
Is formed in a rectangular shape and is cut out from the cubic permanent magnet block material 14.

Accordingly, since the magnet 13 is formed by simply cutting the magnet 13 into a rectangular shape from the cubic permanent magnet block material 14, the conventional arc-shaped polishing process is not required, and the number of manufacturing steps and costs are reduced. .

The spacer-side contact surface 1 of each magnet 13
Since both the outer surface 3a and the outer surface 12b of the spacer 12 are formed in a plane, each magnet 13 can be easily and reliably attached to each outer surface 12b of the spacer 12, and the displacement of each magnet 13 is prevented. be able to.

(2) In this embodiment, the spacer 12
Is the product of the number of magnetic poles P (= 8) of the motor and the division number m (= 1) of the different-pole magnet sandwiched between the same poles (that is, P ×
m = 8)) is formed in the shape of an octagonal column having the same number of outer surfaces 12b as the sides.

Accordingly, when the mechanical gap between the rotor 10 and the stator (not shown) is fixed, the magnetic gap and the number of magnetic poles P of the electric motor × the division number m of the different-polarity magnets interposed between the same poles are expressed as follows. As a result, the magnetic gap when P × m = 8 is small, as shown in FIG.

As a result, it is possible to increase the output of the electric motor. In addition, this embodiment may be changed as follows. In the above embodiment, the number of magnetic poles P of the electric motor is set to 8, the division number m of the different-polarity magnets sandwiched between the same poles is set to 1, and the spacer 12 is formed in an octagonal (P × m = 8) column shape. As shown in FIG. 4, the number of magnetic poles P of the electric motor was set to 8,
The number of divisions m of the different pole (S pole) magnet sandwiched between the same poles (for example, the N pole) is set to 2, and the spacer 12 is hexagonal (P × m
= 16) It may be formed in a columnar shape. in this case,
In addition to the effects described in the features (1) and (2) of the above-described embodiment, as shown in FIG. 3, when P × m = 16, the magnetic gap is further reduced, and the output of the motor is increased. Can be further achieved.

If P × m is set to 8 or more, the number of magnetic poles may be set to 4 or 6, and the division number m may be set to 2 or more. Further, the number of magnetic poles P may be set to 8 and the number of divisions m may be set to 3 or more. In this case, substantially the same effects as those described in the features (1) and (2) of the above embodiment can be obtained.

In the above-described embodiment, each magnet 13 attached to each outer surface 12b is formed in an axial rectangular shape, but the magnet 13 attached to each outer surface 12b is used.
May be formed and implemented in an axial square or a parallelogram. In this case, effects similar to the effects described in the features (1) and (2) of the above embodiment can be obtained.

In the above embodiment, each magnet 13 is arranged on each outer surface 12b and is attached to the spacer 12 with an adhesive, but each magnet 13 is attached to each outer surface 12b.
And may be carried out by molding the spacer 12 with a resin mold material. In this case, effects similar to the effects described in the features (1) and (2) of the above embodiment can be obtained.

In the above embodiment, the present invention is embodied in the rotor of the rotating magnetic field type motor. However, the present invention is not limited to the rotor of the rotating magnetic field type motor, and the present invention is embodied in the rotor of another permanent magnet motor. May be implemented. In this case, effects similar to the effects described in the features (1) and (2) of the above embodiment can be obtained.

Next, technical ideas other than the inventions described in the claims that can be understood from the above embodiment and other examples will be described below together with their effects. (1) The magnet (1) closely attached to the rotor (10) of the electric motor
3) The magnet according to 3), wherein the magnet (13) is formed by cutting a cubic permanent magnet block (14) into a rectangular parallelepiped.

Therefore, according to the invention described in (1), the magnet can be easily manufactured.

[0029]

As described above in detail, according to the first and second aspects of the present invention, the number of manufacturing steps and cost can be reduced, and each magnet can be easily and reliably connected to each side of the spacer. The magnet can be attached to the outer side surface, and the displacement of each magnet can be prevented.

According to the invention described in claim 3, according to claim 1
And 2, the magnetic gap of the rotor can be reduced. According to the fourth aspect of the invention, in addition to the effects of the first to third aspects of the invention, it is possible to increase the output of the electric motor.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a rotor according to an embodiment.

FIG. 2 is a perspective view showing a method of manufacturing a rotor magnet.

FIG. 3 is an explanatory diagram showing the relationship between the magnetic gap and the number of magnetic poles P of the electric motor × the division number m of the different-polarity magnet interposed between the same poles when the mechanical gap between the rotor and the stator is fixed. .

FIG. 4 is a sectional view of a main part of another example of a rotor.

FIG. 5 is a sectional view of a main part of a conventional rotor.

FIG. 6 is a perspective view showing a method for manufacturing a conventional rotor magnet.

[Explanation of symbols]

Reference numeral 10: rotor, 11: rotor shaft as a rotating shaft, 12: spacer, 12b ... side, 13: magnet, P ...
The number of magnetic poles of the motor, m: the number of divisions of different-pole magnets sandwiched between the same poles.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Takanori Ozawa 390 Umeda, Kosai-shi, Shizuoka Prefecture Asmo Co., Ltd. (72) Inventor Mitsuhiko 390 Umeda, Kosai-shi, Shizuoka Prefecture Asmo Co., Ltd. F-term (reference) 5H622 CA02 CA05 CA14 CB06 PP03 PP19 PP20

Claims (4)

[Claims] 1. A rotating shaft (11), a spacer (12) that rotates integrally with the rotating shaft (11), and the spacer (1).
2) In a rotor structure including a plurality of magnets (13) attached to an outer surface of the rotor, the spacer (12) may have a plurality of outer surfaces (12).
b) and is formed in a polygonal column shape, and each outer surface (12
The structure of the rotor, wherein each magnet (13) affixed to b) is formed in an axial quadrangle. 2. The structure of the rotor according to claim 1, wherein the number of sides constituting the outer shape of the spacer (12) is the same as the number of magnetic poles (P) of the electric motor and is divided into different pole magnets. A rotor structure characterized by the same product as the number (m). 3. The rotor structure according to claim 1, wherein the spacer (12) is formed in a polygonal column shape having eight or more sides. 4. An electric motor having the rotor according to claim 1.