JP4495802B2 - Permanent magnet rotor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a permanent magnet rotor in which permanent magnets and yokes are alternately arranged in the circumferential direction.
[0002]
[Prior art]
Examples of this type of permanent magnet type rotor in which permanent magnets and yokes are alternately arranged in the circumferential direction include, for example, Japanese Patent Laid-Open Nos. 63-23542 and 63-92246. It is done. The technology disclosed in the above-mentioned JP-A-63-23542 and JP-A-63-92246 comprises a structure by alternately arranging a plurality of permanent magnets and fan-shaped yokes in the circumferential direction, Non-magnetic end plates are arranged on both end faces of the structure, and the end plate and the structure are connected with bolts, the structure consisting of a permanent magnet and a yoke is fixed to the end plate, and the end plate is attached to the shaft. It is fixed by shrink fitting.
[0003]
Japanese Patent Laid-Open No. 7-312852 discloses a structure in which permanent magnets and yokes are alternately arranged in the circumferential direction, and a connecting portion that connects adjacent ones to the inner peripheral portion of the sector yoke is provided. A method of resin-molding a yoke and a shaft integrally is disclosed.
[0004]
[Problems to be solved by the invention]
However, the methods described in Japanese Patent Laid-Open Nos. 63-23542 and 63-92246 are difficult to assemble because of the large number of parts, and the contact area between the end plate and the shaft is large. Since it is small, there is a problem that a large torque cannot be transmitted.
[0005]
Further, since the number of parts is large and the assembly is troublesome, as described in JP-A-7-312852, the problem is solved by integrally molding the permanent magnet and the yoke.
[0006]
However, in the technique disclosed in Japanese Patent Application Laid-Open No. 7-312852, when adjacent ones are connected at the inner peripheral part of the yoke in order to reduce the number of parts, leakage magnetic flux is generated at the connecting part to reduce the effective magnetic flux. There is a problem of deteriorating motor characteristics.
[0007]
Accordingly, in view of the above problems, the present invention provides a permanent magnet type rotor that reduces the number of parts and simplifies assembly, and prevents the generation of leakage magnetic flux and prevents deterioration of motor characteristics. It is an object.
[0008]
[Means for Solving the Problems]
A permanent magnet rotor according to a first aspect of the present invention is a permanent magnet composed of a plurality of permanent magnets arranged at equal intervals in the circumferential direction, and a yoke body composed of substantially sector-shaped yoke poles arranged between the permanent magnets. In the magnet type rotor, the yoke body is provided with a connecting portion for connecting only the yoke poles constituting the N pole on the inner periphery, and the yoke pole constituting the S pole is disposed between the yoke poles of the N pole . a layer, N pole, a second layer is not both ties yoke pole S pole, provided on the inner peripheral of the connecting portion connecting only yoke pole constituting the S pole, N between the yoke pole of the S pole A permanent magnet / yoke structure comprising three types of layers, a third layer having a yoke pole constituting a pole, and a second layer interposed between the first layer and the third layer configure, the gap between the surface and the connecting portion and the magnet of the permanent magnet-yoke structure to the resin mold Together, is characterized in that integrally formed, it is inserted through the shaft hole formed in the boss to boss resin.
[00 09 ]
The permanent magnet rotor according to claim 2 is characterized in that a nonmagnetic material is used for the shaft.
[001 0 ]
In the permanent magnet type rotor according to claim 1 of the present invention, since the permanent magnet / yoke structure is formed by laminating three kinds of layers, generation of leakage magnetic flux is prevented by the second layer. It is possible to prevent the motor characteristics from deteriorating.
[001 1 ]
In addition , since the yoke body, the permanent magnet, and the boss are firmly and integrally bonded together, high accuracy and strength can be provided.
[001 2 ]
According to the permanent magnet type rotor of claim 2 , even if the yoke body is fixed to the shaft by knurling or shrink fitting by using a non-magnetic material for the shaft, the leakage magnetic flux Does not occur and the contact area is large, so that a large torque can be transmitted.
[001 3 ]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
[001 4 ]
FIG. 1 is a cross-sectional view of a rotor main body 10. The rotor main body 10 is press-fitted in the axial direction of a substantially cylindrical permanent magnet / yoke structure 14 and the central portion of the permanent magnet / yoke structure 14. It is comprised with the shaft 12 which is.
[001 5 ]
FIG. 2A shows a cross-sectional view of the permanent magnet / yoke structure 14, and the permanent magnet / yoke structure 14 includes a yoke body 18 and yoke poles positioned in the circumferential direction of the yoke body 18. 20 and a plurality of permanent magnets 16 arranged at equal intervals in the circumferential direction so as to have different polarities alternately.
[001 6 ]
The yoke body 18 is configured by laminating thin steel plates, and in the present invention, there are three types of laminated steel plate layers. That is, as shown in FIGS. 1 and 2, the layer 1 in which the N poles of the yoke pole 20 are connected, the layer 2 in which the N pole and S pole of the yoke pole 20 are not connected together, and the yoke pole 20 as shown in FIG. Three types of yoke structures of the layer 3 to which the S poles are connected are formed.
[00 17 ]
As shown in FIG. 2, the layer 1 in which the north poles of the yoke poles 20 are connected is formed by laminating the base parts of the yoke poles 20 serving as the north poles integrally with the ring-shaped connecting portions 22, and 20 is arranged between the N pole yoke poles 20 and laminated in the same manner.
[00 18 ]
Further, as shown in FIG. 3, the layer 2 having no connection between the N pole and the S pole is formed by laminating a substantially sector-shaped yoke pole 20 in the circumferential direction.
[00 19 ]
Furthermore, as shown in FIG. 4, the layer 3 of the yoke pole 20 connected to the south pole becomes a north pole by laminating the base portions of the yoke pole 20 serving as the south pole with a ring-shaped connecting portion 24. The yoke pole 20 is disposed between the S pole yoke poles 20 and laminated in the same manner. The inner diameters of the connecting portions 22 and 24 of the yoke are set such that the shaft 12 can be press-fitted.
[002 0 ]
Thus, there are three types of layers: the layer 1 in which the N pole yoke pole 20 is connected, the layer 2 in which both the N pole and S pole yoke 20 are not connected, and the layer 3 in which the S pole yoke pole 20 is connected. The yoke 1 is formed, and the poles of the permanent magnets 16 are inserted so that the poles of the yoke poles 20 are opposed to each other, and then, as shown in FIG. Between the layer 3 where the yoke pole 20 of the S pole and the pole 20 of the S pole are connected, the layer 2 where the N pole and the yoke pole 20 of the S pole which are sufficiently thick so that no leakage magnetic flux is generated is sandwiched between them. An integral permanent magnet / yoke structure 14 in which members are fixed by bonding or the like is formed.
[002 1 ]
As shown in FIG. 1, the rotor body 10 is formed by press-fitting and fixing the shaft 12 whose surface is knurled into the permanent magnet / yoke structure 14.
[002 2 ]
Here, since the connecting portions 22 and 24 of the permanent magnet / yoke structure 14 are fitted to the shaft 12, an end plate or the like is not required as in the prior art, so the number of parts is reduced and assembly is simplified. Is done. Further, the fitting portion between the outer peripheral surface of the shaft 12 and the inner peripheral surface of the permanent magnet / yoke structure 14 is formed by the layer 1 connected with the N pole yoke pole 20 and the layer 3 connected with the S pole yoke pole 20. It is a layer portion of the inner connecting portions 22 and 24. Therefore, since the length of the fitting portion with the shaft 12 can be sufficiently long in the axial direction, high accuracy and strength can be secured, and a large torque can be secured. Can be transmitted.
[002 3 ]
Further, between the layer 1 to which the N pole yoke pole 20 is connected and the layer 3 to which the S pole yoke pole 20 is connected, a layer 2 in which the N pole and S pole yoke 20 are not connected is provided. Therefore, the generation of magnetic flux leakage is prevented and the motor characteristics are not deteriorated.
[002 4 ]
By using a non-magnetic material such as stainless steel for the shaft 12, no leakage magnetic flux is generated even if the inner diameter of the yoke body 18 is fixed by a method such as knurling or shrink fitting, and the shaft 12 Since the contact area between the yoke body 18 and the yoke body 18 is large, a large torque can be transmitted.
[002 5 ]
(Second embodiment)
FIG. 5 shows a sectional view of the rotor body 10 of the second embodiment.
[002 6 ]
By the first embodiment and the resin 30 in the permanent magnet-yoke structure 14 having the same structure is obtained by molding fixed, in this case, are formed integrally with ball scan 32. Further, when the boss 32 is formed, a serration 34 for fixing the shaft 12 is integrally formed inside the boss 32. Then, the narrow-diameter portion 12a at the end of the shaft 12 is inserted into the serration 34, and the nut 36 is screwed through the washer 38, so that the shaft 12 and the resin-molded permanent magnet / yoke structure 14 are integrated. It has become.
[00 27 ]
Thereby, in addition to the effect of Example 1, the yoke main body 18, the permanent magnet 16, and the boss | hub 32 adhere more firmly, and the rotor main body 10 provided with the high precision and intensity | strength can be formed. Further, by integrally forming the shaft 12 and the boss 32, application to various types of motors becomes possible.
[00 28 ]
【The invention's effect】
As described above, the permanent magnet rotor of the present invention reduces the number of parts and simplifies the assembly, prevents the generation of leakage magnetic flux, does not deteriorate the motor characteristics, and A large torque can be transmitted. In addition, it can secure sufficient strength to withstand molding and handling, and can be applied to various types of motors by being integrally formed with the shaft and boss.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view taken along line AA in FIG. 2B of a rotor body according to an embodiment of the present invention.
2A and 2B are a cross-sectional view and an arrangement configuration diagram of layers in which N pole yoke poles are connected according to an embodiment of the present invention.
FIGS. 3A and 3B are a cross-sectional view and an arrangement configuration diagram of a layer in which N pole and S pole yoke poles are not connected to each other according to the embodiment of the present invention.
FIGS. 4A and 4B are a cross-sectional view and an arrangement configuration diagram of layers in which yokes of S poles are connected according to the embodiment of the present invention.
FIG. 5 is a cross-sectional view of a rotor body according to Example 2 of an embodiment of the invention.
[Explanation of symbols]
1 N pole connected layer (first layer)
2 Layer not connected to either N pole or S pole (second layer)
3 Layer connected with S pole (third layer)
DESCRIPTION OF SYMBOLS 10 Rotor main body 12 Shaft 14 Permanent magnet and yoke structure 16 Permanent magnet 18 Yoke main body 20 Yoke pole 22 Connecting part 24 Connecting part 30 Resin 32 Boss

Claims (2)

In the permanent magnet type rotor composed of a plurality of permanent magnets arranged at equal intervals in the circumferential direction and a yoke body composed of a substantially fan-shaped yoke pole arranged between the permanent magnets,
The yoke body
A first layer in which a connecting portion for connecting only the yoke poles constituting the N pole is provided on the inner periphery, and the yoke pole constituting the S pole is disposed between the yoke poles of the N pole ;
A second layer in which the north and south poles are not connected;
It is composed of three types of layers: a third layer in which a connecting portion for connecting only the yoke poles constituting the S pole is provided on the inner periphery, and the yoke pole constituting the N pole is disposed between the yoke poles of the S pole. ,
A permanent magnet / yoke structure is configured by interposing a second layer between the first layer and the third layer,
While resin-molding the surface of the permanent magnet / yoke structure and the gap between the connecting portion and the magnet, the boss is integrally formed of resin,
A permanent magnet type rotor having a shaft inserted through a hole formed in the boss . Claim 1 Symbol placement of the permanent magnet type rotor, characterized in that it uses a non-magnetic material to the shaft.

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