JP2001037122A - Rotor for motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To satisfactorily support a permanent magnet by stabilizing and improving rotating characteristics, by using a simple constitution. SOLUTION: A radially protruding portion is constituted of a locking portion 175 of an end plate 174, made of a nonmagnetic material so as to support a plurality of permanent magnets 172 to sharply reduce influence to a revolving magnetic field, and a permanent magnet 172 is supported with respect to an the axial direction which has not heretofore been supported by the portion 175 of the plate 174, and the magnet is supported satisfactorily without using a separate component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor of an inner rotor type motor having a plurality of permanent magnets on an outer peripheral portion.

[0002]

2. Description of the Related Art Generally, in various motors of the inner rotor type, a rotor (rotor) having a plurality of permanent magnets on its outer periphery is rotatable in an inner space of a fixed armature arranged on the outer periphery. It is supported by. In such a rotor, for example, as shown in FIG. 8, a plurality of permanent magnets 2 are provided on an outer peripheral portion of a rotor core 1 formed of a substantially cylindrical laminated body.
Are mounted so as to be inserted in the axial direction, and the end faces of the respective permanent magnets 2 are received by a magnet supporting portion 3 provided so as to protrude from the outer peripheral surface of the rotor core 1 so as to be mechanically held. Has been done.

[0003] More specifically, the entire rotor core 1 is composed of a laminate of a plurality of magnetic core plates.
There are two types depending on the shape of the part that constitutes. One is provided with a circumferential supporting portion 3a in which a portion corresponding to the magnet supporting portion 3 has a substantially rectangular shape, and the other is a portion having a substantially T-shaped portion corresponding to the magnet supporting portion 3. And a radial support 3b. A magnetic core plate laminate having a radial support portion 3b is disposed so as to sandwich the magnetic core plate laminate having the circumferential support portion 3a from both ends in the axial direction, and a circumferential end surface of the permanent magnet 2 is provided. 2a is received in the magnetic core plate laminate having the circumferential support portion 3a and is supported in the circumferential direction;
The outer peripheral surface 2b of the permanent magnet 2 is received by the magnetic core plate laminate having the above-described radial support portion 3b and is supported in the radial direction.

[0004]

However, in such a conventional rotor, the laminated body of the radial support portions 3b projecting outward in a substantially T-shape is made of a magnetic material. Therefore, a state in which the magnetic flux of the rotating magnetic field is collected on the laminated body of the radial support portions 3b made of the magnetic material often occurs. As a result, the rotating magnetic field is disturbed, and the cogging torque increases. The problem has arisen.

[0005] In the conventional example shown in Fig. 8, the radial support portion 3b which disturbs the magnetic field is divided and arranged at two positions at both ends in the axial direction so as to minimize the radial support portion 3b as described above. However, the effects on the magnetic field still remain.

[0006] In addition, the conventional rotor core is provided only with a circumferential support portion 3a and a radial support portion 3b for holding the circumferential end surface 2a and the outer circumferential surface 2b of the permanent magnet 2, respectively. Since a member for holding the axial end surface of the permanent magnet 2 is not provided, a locking member for supporting the permanent magnet 2 in the axial direction is separately required, which increases the number of parts and increases the number of parts. There is also a tendency for the support structure of the magnet 2 to lack reliability.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a rotor for an electric motor which has a simple structure and can favorably support a permanent magnet while improving rotation characteristics.

[0008]

In order to achieve the above-mentioned object, according to the first aspect of the present invention, a substantially cylindrical rotor core made of a laminate of a plurality of magnetic core plates fixed to a shaft member is provided. And a plurality of permanent magnets fixed on the outer peripheral side of the rotor core so as to be aligned in the circumferential direction. The cylindrical outer peripheral surface of the rotor core has a peripheral surface of each of the permanent magnets. A circumferential support portion protruding radially outward to receive the axial end face is provided so as to extend along the axial direction, and at least one axial end face of the rotor core has a non- An end plate made of a magnetic material is provided,
The outer peripheral edge of the end plate is provided with a locking portion projecting in a substantially L-shape radially outward from a position corresponding to each of the permanent magnets. An axial support portion that receives the axial end surface of the permanent magnet, and a radial support portion that extends from the outer end side of the axial support portion so as to be bent in the axial direction and receives the outer peripheral surface of each of the permanent magnets are provided. ,
The permanent magnets are supported in three directions of a circumferential direction, an axial direction, and a radial direction by a circumferential support portion of the rotor core and an axial support portion and a radial support portion of the end plate. ing.

According to the second aspect of the present invention, the locking portion of the end plate according to the first aspect has substantially the same circumferential position as facing the circumferential supporting portion of the rotor core. It is arranged so that it becomes.

Further, in the invention according to claim 3, the axial support provided on the locking portion of the end plate according to claim 2 is larger than the circumferential support provided on the rotor core. It has a circumferential width.

Further, according to a fourth aspect of the present invention, the circumferential support portion provided on the rotor core according to the first aspect has a substantially rectangular cross section in a direction orthogonal to the axial direction. Have been.

Further, in the invention according to the fifth aspect, the gap between the end plate, the rotor core and each permanent magnet according to the first aspect is filled with an adhesive.

Further, in the invention according to claim 6, an adhesive tape is wound around and fixed to the outer peripheral side of the end plate and each permanent magnet according to claim 1.

Further, in the invention according to claim 7, the adhesive tape according to claim 6 is made of a resin tape.

Further, in the invention according to claim 8, the radial support portion of the end plate provided at one axial end of the rotor core according to claim 1 is provided at the axial center of the rotor core. From the section to the other end.

According to the present invention having such a configuration,
Since the portion projecting outward in the radial direction so as to support the permanent magnet is constituted by the locking portion of the end plate made of a non-magnetic material, the influence on the rotating magnetic field is greatly reduced. Further, since the locking portion of the end plate made of the non-magnetic material is configured to support the permanent magnet in the axial direction, which has not been conventionally supported, the support of the permanent magnet can be performed without using a separate component. The nature is improved.

Further, if the end plate, the rotor core and the respective permanent magnets are connected with an adhesive or an adhesive tape as in the present invention, the supportability of the permanent magnets is further improved. Becomes

Further, as in the present invention, if the radial support portion of the end plate provided at one end of the rotor core is extended in the axial direction toward the other end, the support of the permanent magnet can be achieved. In particular, when the radial support portion of one end plate is extended to the other end, only one end plate needs to be provided, and the number of parts can be reduced by omitting the other side. Is reduced.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. First, an overall structure of an example of an inner rotor type electric motor to which the present invention is applied will be described. As shown in FIG. 2, a fixed armature 12 is attached to an inner peripheral wall of a motor case 11 formed in a substantially hollow cylindrical shape, and a rotating armature is provided inside the fixed armature 12. The child 13 is arranged. This rotor 1
The center shaft 14 is rotatably supported by a pair of bearings 15 and 16 disposed at both ends in the axial direction of the motor case 11, and has a substantially central portion in the axial direction of the center shaft 14. The rotor core 17 as also shown in FIGS. 1, 3, 4 and 5 is screwed.

The rotor core 17 is formed of a substantially cylindrical laminate in which a plurality of magnetic core plates (see reference numeral 171 in FIG. 5) made of an electromagnetic steel plate or the like are laminated in the axial direction.
A plurality of permanent magnets 1 are provided on the outer peripheral surface of the rotor core 17.
Are mounted so as to be arranged in the circumferential direction.

At this time, as shown in FIG. 5, in particular, each magnetic core plate 1 constituting the rotor core 17 is formed.
On the outer peripheral edge of the permanent magnet 71, substantially rectangular protrusions 171a, 171a,... Protruding outward in the radial direction are integrally provided at a pitch interval corresponding to the circumferential width of each permanent magnet 172. Have been. And each of these projections 171a
Are gathered in the axial direction in a laminated manner, so that the circumferential supporting portions 173, 173,... Extending in the axial direction form the circumferential width of each permanent magnet 172 on the outer circumferential surface of the rotor core 17. Are formed at a pitch interval corresponding to.

That is, each of the circumferential support portions 173 is
The permanent magnet 172 is provided so as to extend in the axial direction at a portion between the pair of circumferentially adjacent permanent magnets 172, 172. The permanent magnet 172 is supported in the circumferential direction by abutting the direction end surface 172a (see FIG. 6).

On both end faces in the axial direction of the rotor core 17, thin end plates 174, 174 made of a non-magnetic material are provided.
Are arranged respectively. At the center of each of these end plates 174 is a through hole 1 for allowing the center shaft 14 to pass therethrough.
A plurality of locking portions 175, 17 projecting radially outward from positions corresponding to the respective permanent magnets 172 are formed on the outer peripheral edge of the end plate 174.
.. Are provided.

Each of the locking portions 175 is provided with the rotor core 1.
The circumferential position of the circumferential support portion 173 on the seventh side is substantially the same as that of the circumferential support portion 173, and the protrusion is outwardly formed in a substantially L-shape. That is, the locking portion 175 is
An axial support portion 175a integrally protruding radially outward from an outer peripheral edge of the end plate 174, and bent at a substantially right angle from an outer end side of the axial support portion 175a toward an axial center side. Radial support 17 extending
5b.

Each of the locking portions 175 provided on the end plate 174 has a larger circumferential width than the circumferential supporting portion 173 on the rotor core 17 side, as shown in FIG. And a pair of circumferentially adjacent permanent magnets 17
2 and 172 are in contact with each other so as to straddle over one axial support portion 175a, whereby the pair of permanent magnets 172 and 172b are disposed.
172 are supported in the axial direction. The outer peripheral surfaces 172c (see FIG. 6) of the pair of permanent magnets 172, 172 are in contact with the one radial support portion 175b.
2,172 are supported in the radial direction.

As described above, the plurality of permanent supports are provided by the circumferential support portion 173 provided on the rotor core 17 side and the axial support portion 175a and the radial support portion 175b provided on the end plate 174 side. Magnets 172, 172, ...
Is configured to be received and held in three directions of a circumferential direction, an axial direction, and a radial direction.

In this embodiment, the end plate 1
An adhesive (not shown) is filled in a gap between the permanent magnet 74, the rotor core 17, and each of the permanent magnets 172.
An adhesive tape 176 is wound around and fixed to the outer periphery of the end plate 174 and each permanent magnet 172. As the adhesive tape 176, for example, a resin tape impregnated with an epoxy resin or the like is used.

According to the present embodiment having such a configuration, the portion projecting outward in the radial direction so as to support each permanent magnet 172, that is, the locking portion 175 of the end plate 174,
The end plate 1 is made of a non-magnetic material.
The locking portion 175 has almost no effect on the rotating magnetic field, and the state of formation of the rotating magnetic field is greatly improved.
Further, the locking portion 175 of the end plate 174 made of the non-magnetic material is used.
Is configured to support also in the axial direction, which was conventionally supported by a separate component, so that the supportability of the permanent magnet 172 is improved while realizing a simple configuration.

In the present embodiment, the end plate 174, the rotor core 17, and the permanent magnets 172 are connected by an adhesive and an adhesive tape 176 (see FIG. 1). The support of 172 is made more reliable.

On the other hand, in the embodiment shown in FIG.
A radial support portion 177b of the locking portion 177 provided on the end plate 174 extends to a central portion in the axial direction of the rotor core. With such a configuration, the supportability of the permanent magnet can be further improved.

Although not shown, a radial support portion 177b of an end plate 174 provided at one end of the rotor core is provided.
Is further extended in the axial direction from the central portion in the axial direction to reach the other axial end of the rotor core, the end plate on the other side can be omitted, and the number of parts can be reduced. .

Although the embodiments of the present invention made by the inventor have been specifically described above, the present invention is not limited to the above-described embodiments, and can be variously modified without departing from the gist thereof. Needless to say. For example, in each of the embodiments described above, the present invention is applied to a motor. However, the present invention can be similarly applied to a generator other than a motor.

[0033]

As described above, according to the present invention, the portion projecting in the radial direction so as to support each of the plurality of permanent magnets is constituted by the locking portion of the end plate made of a non-magnetic material. In addition to significantly reducing the effect on the rotating magnetic field, the permanent magnet is supported in the axial direction, which was not conventionally supported, by the locking portion of the end plate made of the non-magnetic material. Therefore, it is possible to favorably support the permanent magnets, and with a simple configuration, it is possible to stabilize and improve the rotation characteristics, and to favorably support the permanent magnets.
The reliability of the magnet support structure can be improved while improving the performance of the electric motor.

Further, according to the present invention, the end plate, the rotor core and each permanent magnet are connected to each other with an adhesive or an adhesive tape, so that the supportability of the permanent magnet is further improved. The above-described effects can be further enhanced by adopting such a configuration.

Further, the present invention further improves the supportability of the permanent magnet by forming the radial support portion provided on the end plate to extend in the axial direction, and in particular, further improves the radial support portion of the end plate. By extending to the end side, it is possible to omit the end plate on the other side and to include a configuration for reducing the number of parts. By adopting such a configuration, it is possible to further enhance the above-described effect. Can be.

[Brief description of the drawings]

FIG. 1 is an external perspective explanatory view showing only a rotor core according to an embodiment of the present invention.

FIG. 2 is an explanatory cross-sectional view illustrating an example of an inner rotor type electric motor including the rotor illustrated in FIG. 1;

FIG. 3 is an explanatory side view of a rotor in which the rotor core shown in FIG. 1 is fixed to a shaft member.

FIG. 4 is an explanatory front view of the rotor shown in FIG. 3;

FIG. 5 is an explanatory front view showing an enlarged locking portion.

FIG. 6 is a partially exploded perspective view showing an assembled state of a permanent magnet.

FIG. 7 is an explanatory external perspective view illustrating a locking portion in another embodiment of the present invention in an enlarged manner.

FIG. 8 is a partially exploded perspective view showing an assembled state of a permanent magnet in a conventional configuration.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Motor case 12 Fixed armature 13 Rotor 17 Rotor core 171 Magnetic core plate 172 Permanent magnet 173 Circumferential support part 174 End plate 175 Lock part 175a Axial support part 175b Radial support part 176 Adhesive tape 177 Lock part 177b Radial support

Claims (8)

[Claims] 1. A substantially cylindrical rotor core comprising a laminated body of a plurality of magnetic core plates fixed to a shaft member, and a plurality of rotor cores fixed to be arranged in a circumferential direction on an outer peripheral side of the rotor core. In the rotor of the electric motor having a permanent magnet of, the cylindrical outer peripheral surface of the rotor core, a circumferential supporting portion projecting radially outward to receive the circumferential end surface of each of the permanent magnets, At least one end face in the axial direction of the rotor core is provided with an end plate made of a non-magnetic material, and is provided at an outer peripheral edge of the end plate. A locking portion is provided that protrudes radially outward from a position corresponding to each of the permanent magnets in a substantially L-shape. The locking portion has a shaft that receives an axial end surface of each of the permanent magnets. Direction support part and bends in the axial direction from the outer end side of this axial support part. A radial support portion extending to receive the outer peripheral surface of each of the permanent magnets is provided, and a circumferential support portion of the rotor core, and an axial support portion and a radial support portion of the end plate, A rotor for an electric motor, wherein each permanent magnet is supported in three directions of a circumferential direction, an axial direction, and a radial direction. 2. The locking portion of the end plate is arranged so that its circumferential position is substantially the same so as to face the circumferential supporting portion of the rotor core. A rotor for an electric motor according to claim 1. 3. The axial support provided on the locking portion of the end plate has a larger circumferential width than the circumferential support provided on the rotor core. Item 3. A rotor for an electric motor according to item 2. 4. The electric motor according to claim 1, wherein the circumferential support provided on the rotor core has a substantially rectangular cross section in a direction perpendicular to the axial direction. Rotor. 5. The rotor for an electric motor according to claim 1, wherein a gap between the end plate, the rotor core, and each permanent magnet is filled with an adhesive. 6. The rotor for an electric motor according to claim 1, wherein an adhesive tape is wound around and fixed to the outer peripheral sides of the end plate and each of the permanent magnets. 7. The motor rotor according to claim 6, wherein the adhesive tape is made of a resin tape. 8. A radial support portion of an end plate provided at one axial end of the rotor core extends from a central portion in the axial direction of the rotor core to the other end. The rotor of an electric motor according to claim 1, wherein: