JP6233016B2 - Rotor and permanent magnet motor - Google Patents

Description

  The present invention relates to a rotor and a permanent magnet electric motor using the rotor.

  A conventional permanent magnet motor has an inner rotor type motor in which a rotor having a permanent magnet is rotatably arranged inside a stator that generates a rotating magnetic field. For example, a blower fan mounted on an air conditioner is provided. Used as a brushless DC motor for rotational driving.

  The rotor of such a permanent magnet motor is, for example, pressed between a cylindrical permanent magnet arranged on the outer peripheral side, a columnar holding member crimped to a shaft, and the permanent magnet and the holding member. The structure is provided with a flexible magnetic body. The holding member functions as an inner peripheral iron core, and the magnetic body functions as a buffer member because it has flexibility. Due to the structure of this rotor, it is known that the vibration caused by the rotation of the permanent magnet is absorbed by the buffer member and is not easily transmitted from the permanent magnet to the inner peripheral iron core or shaft, and the vibration isolation effect of the rotor can be obtained ( For example, see Patent Document 1).

  However, the vibration isolating structure of the rotor according to Patent Document 1 has a small thickness and a small volume of the buffer member provided between the permanent magnet and the inner peripheral iron core. There is a risk of deterioration of vibration isolation. As a countermeasure, when the volume of the buffer member is increased, more vibration energy is absorbed by the buffer member and the vibration isolation of the rotor is improved, but there is a problem that the rotor becomes large.

Japanese Patent Laid-Open No. 5-252677

  In view of the above-described problems, an object of the present invention is to provide a rotor and a permanent magnet motor that can improve the vibration isolation performance of the rotor without changing the size of the rotor.

In order to solve the above problems, the rotor of the present invention includes a shaft, an inner peripheral side iron core fixed to the shaft, a columnar buffer member covering the inner peripheral side iron core, and a cylindrical shape covering the outer peripheral side of the buffer member. The inner peripheral iron core has a plurality of inner peripheral iron core pieces perpendicular to the shaft and having a predetermined gap in the axial direction of the shaft, and the inner peripheral iron core pieces are shafts. It is arranged on the shaft with a predetermined gap in the direction, and the buffer member covers a plurality of inner peripheral core pieces so as to fill the predetermined gap. The permanent magnet motor according to the present invention includes the rotor and a stator arranged to face the outer peripheral side of the rotor at a predetermined interval.

According to the rotor and the permanent magnet motor of the present invention, the inner peripheral iron core includes a plurality of inner peripheral iron core pieces that have a predetermined gap in the axial direction of the shaft and are orthogonal to the shaft, and a plurality of inner peripheral iron core pieces. Is disposed on the shaft with a predetermined gap in the axial direction, and the buffer member covers the plurality of inner core pieces so as to fill the predetermined gap, thereby reducing the volume of the buffer member without changing the size of the rotor. Since it can be enlarged, the vibration isolation of the rotor can be improved.

It is explanatory drawing which shows the rotor by this invention, (a) is a top view, (b) is AA sectional drawing of (a). It is sectional drawing which shows the permanent magnet electric motor using the rotor by this invention. It is a top view which shows the permanent magnet electric motor using the rotor by this invention. It is explanatory drawing which shows other embodiment of the rotor by this invention, (a) is sectional drawing which shows 2nd Embodiment equivalent to the AA cross section of Fig.1 (a), (b) is FIG. It is sectional drawing which shows 3rd Embodiment corresponded to the AA cross section of a).

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 to 4 are views for explaining a rotor and a permanent magnet motor using the rotor in the present embodiment. The permanent magnet motor is an inner rotor type motor in which a rotor having a permanent magnet is rotatably arranged in a stator that generates a rotating magnetic field. For example, the permanent magnet motor is used for rotationally driving a blower fan mounted on an air conditioner. Used as a brushless DC motor.

As shown in FIG. 1, the rotor 1 includes a shaft 2, an inner peripheral side iron core 3 fixed to the shaft 2, a columnar buffer member 4 covering the inner peripheral side iron core 3, and an outer peripheral side of the buffer member 4. A cylindrical permanent magnet 5 is provided. The inner peripheral iron core 3 includes five inner peripheral iron core pieces 31 that are orthogonal to the shaft 2 with a predetermined gap S in the axial direction of the shaft 2. The five inner peripheral iron core pieces 31 are each formed in a disk shape. Each inner peripheral iron core piece 31 has a hole 311 for mounting to the shaft 2 at the center, and is fixed by crimping the shaft 2 and the hole 311 after passing the shaft 2 through the hole 311. In the present embodiment, five inner peripheral core pieces 31 are arranged on the shaft 2 at equal intervals in the axial direction, and four gaps S of the same height are formed in the axial direction. In addition, although the inner peripheral side iron core piece 31 is formed in disk shape, you may form not only in this but in a polygon plate shape. In addition, although the five inner peripheral core pieces 31 are crimped to the shaft 2, the present invention is not limited to this, and two or more inner peripheral cores 31 are crimped to the shaft 2 so as to form a predetermined gap S. It only has to be.

  The buffer member 4 is made of, for example, rubber or resin composed of CR (chloroprene rubber), PET (polyethylene terephthalate), PBT (polybutylene terephthalate), or the like. The buffer member 4 fills four gaps S formed between the five inner peripheral core pieces 31, and the upper end surface 312 and the lowermost portion of the uppermost inner peripheral core piece 31 excluding the periphery of the shaft 2. The lower end surface 313 of the inner peripheral side iron core piece 31 is also covered. The buffer member 4 may cover the upper end surface 312 of the uppermost inner circumferential core piece 31 and the lower end surface 313 of the lowermost inner circumferential core piece 31 up to the periphery of the shaft 2.

  The permanent magnet 5 is formed of, for example, a so-called plastic magnet in which magnet powder is hardened with a resin, is longer in the axial direction than the buffer member 4, and is disposed so as to protrude from the upper end surface 41 and the lower end surface 42 of the buffer member 4. Yes. Four protrusions 51 are formed on the inner peripheral surface of the permanent magnet 5. The rotor 1 fills the buffer member 4 between the shaft 2 and the permanent magnet 5 in a state where the inner peripheral side iron core piece 31 is crimped to the shaft 2, and the shaft 2, the buffer member 4 and the permanent magnet 5 are filled. It is formed by integral molding. The permanent magnet 5 is magnetized after the rotor 1 is formed. In addition, the rotor 1 can also integrally mold the buffer member 4 on the shaft 2 in advance. In this case, four recesses are formed on the outer peripheral surface of the shock-absorbing member 4 so that the four protrusions 51 can be accommodated during integral molding, and after the integral molding, the protrusion 51 of the permanent magnet 5 is fitted into the recess of the shock-absorbing member 4. You may let them.

  As shown in FIGS. 2 and 3, the permanent magnet motor M includes the rotor 1 and the stator 6 described above. The stator 6 includes a stator core 61, an insulator 62, and a stator winding 63. The stator core 61 is formed in a cylindrical shape by laminating a plurality of thin steel plates, and includes an annular back yoke portion 611 and a plurality of teeth portions 612 extending from the back yoke portion 611 to the inner diameter side. An insulator 62 is formed integrally with the stator core 61, and a stator winding 63 is wound around the teeth portion 612 via the insulator 62.

  The stator 6 thus configured is molded with a mold resin except for the tip surface 6121 of the teeth portion 612 (the inner peripheral surface of the stator core 61) of the stator core 61 around which the stator winding 63 is wound. The cylindrical outer shell 64 is formed by molding, and the tip surface 6121 of the tooth portion 612 is disposed so as to face the outer peripheral surface 52 of the rotor 1 with a predetermined interval (so-called air gap).

  According to the rotor 1 according to the first embodiment and the permanent magnet motor M using the rotor 1 described above, the inner peripheral side iron core 3 is provided with a predetermined gap S in the axial direction of the shaft 2. 2, and the buffer member 4 covers the inner core piece 31 so as to fill the predetermined gap S, so that the size of the rotor 1 is not changed. The volume of the member 4 can be increased. Therefore, more vibration energy is absorbed by the buffer member 4, and vibration isolation properties such as the axial direction and circumferential direction of the rotor 1 can be improved.

  Next, the rotor 1 according to the second embodiment will be described with reference to FIG. Note that the same reference numerals are given to the same components as those in the first embodiment described above, and the description thereof is omitted. As shown in FIG. 4A, the rotor 1 is configured so that the inner peripheral core pieces 31 are axially arranged with respect to the five inner peripheral core pieces 31 provided in the inner peripheral iron core 3 described above. It further includes a connecting portion 314 formed to be connected. The connecting portion 314 is formed in a cylindrical shape and is crimped after the shaft 2 is inserted.

  According to the rotor 1 according to the second embodiment, as in the first embodiment described above, it is possible to improve the vibration isolating properties such as the axial direction and the circumferential direction of the rotor 1. Furthermore, in the first embodiment described above, it is necessary to crimp the five inner peripheral iron core pieces 31 of the inner peripheral iron core 3 to the shaft 2 respectively, but in the second embodiment, the connecting portion of the inner peripheral iron core 3 Since it is only necessary to crimp 314 to the shaft 2, it can be easily assembled.

  Next, the rotor 1 according to the third embodiment will be described with reference to FIG. Note that the same reference numerals are given to the same components as those in the first embodiment described above, and the description thereof is omitted. As shown in FIG. 4B, the rotor 1 is formed by laminating a plurality of thin steel plates, for example, instead of the five inner peripheral core pieces 31 provided in the inner peripheral iron core 3 described above. Five inner peripheral core pieces 32 are provided. The five inner peripheral side iron core pieces 32 are each formed in a disk shape. Each inner peripheral iron core piece 32 has a hole 321 for mounting on the shaft 2 at the center, and is fixed by crimping the shaft 2 and the hole 321 after passing the shaft 2 through the hole 321. The buffer member 4 also covers the upper end surface 322 of the uppermost inner peripheral side core piece 32 excluding the periphery of the shaft 2 and the lower end surface 323 of the lowermost inner peripheral side core piece 32. The buffer member 4 may cover the upper end surface 322 of the uppermost inner peripheral core piece 32 and the lower end surface 323 of the lowermost inner peripheral core piece 32 up to the periphery of the shaft 2.

  According to the rotor 1 according to the third embodiment, as in the first embodiment described above, it is possible to improve the vibration isolation properties of the rotor 1 in the axial direction and the circumferential direction. Further, in the first embodiment described above, the inner peripheral side core pieces 31 that are not stacked are pressure-bonded to the shaft 2, but in the third embodiment, a plurality of inner peripheral side core pieces 32 that are formed by being stacked are provided. Therefore, the crimping | compression-bonding state with respect to the shaft 2 of the inner peripheral side iron core piece 32 can further be strengthened.

DESCRIPTION OF SYMBOLS 1 Rotor 2 Shaft 3 Inner peripheral side core 31 Inner peripheral side core piece 311 Hole 312 Upper end surface 313 Lower end surface 314 Connection part 32 Inner peripheral side core piece 321 Hole 322 Upper end surface 323 Lower end surface 4 Buffer member 41 Upper end surface 42 Lower end surface DESCRIPTION OF SYMBOLS 5 Permanent magnet 51 Protruding part 6 Stator 61 Stator iron core 611 Back yoke part 612 Teeth part 6121 Tip surface 62 Insulator 63 Stator winding 64 Outer M Permanent magnet motor S Gap

Claims (2)

A rotor including a shaft, an inner peripheral iron core fixed to the shaft, a columnar buffer member covering the inner peripheral iron core, and a cylindrical permanent magnet covering the outer peripheral side of the buffer member. ,
The inner peripheral iron core includes a plurality of inner peripheral iron core pieces that have a predetermined gap in the axial direction of the shaft and are orthogonal to the shaft, and the inner peripheral iron core pieces have the predetermined gap in the axial direction. The rotor, wherein the rotor is disposed on the shaft, and the buffer member covers the plurality of inner peripheral iron core pieces so as to fill the predetermined gap.   A permanent magnet electric motor comprising: the rotor according to claim 1; and a stator disposed so as to face an outer peripheral side of the rotor with a predetermined interval.

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