JP2017085804A - Permanent magnet electric motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the coupling strength among an inner circumference side core, an anti-vibration member and an outer circumference side core in a rotation direction when the rotor is rotating.SOLUTION: The permanent magnet electric motor includes: a rotor which has a an anti-vibration member filled between an inner circumference side core and an outer circumference side core. The inner circumference side core includes a plurality of first projections each of which protrudes from an outer periphery wall toward the outer circumference side core and which extends along the outer periphery wall in an axial direction of a shaft. The outer circumference side core includes a plurality of second projections each of which protrudes from an inner periphery wall toward the inner circumference side core and which extends along inner periphery wall in the axial direction of the shaft. At least one of the side wall of the plurality of first projections or the side wall of the plurality of second projections has a groove which extends the axial direction of the shaft and which filled with anti-vibration member.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a permanent magnet electric motor including a rotor having a vibration isolation member.

  As a conventional permanent magnet motor, there is 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. As this type of electric motor, for example, there is a brushless DC motor for rotationally driving a blower fan mounted on an outdoor unit of an air conditioner.

  This brushless DC motor includes a cylindrical stator that is covered with a motor shell formed of resin, and a rotor that has a rotor core and is disposed on the inner peripheral side of the stator. The rotor includes a shaft, a cylindrical inner peripheral iron core fixed to the shaft, a cylindrical outer iron core disposed around the shaft on the outer peripheral side of the inner peripheral core, and an outer peripheral side of the outer iron core. It has a plurality of arranged permanent magnets, and an anti-vibration member that covers the upper and lower end surfaces of the inner peripheral iron core and outer peripheral iron core and is filled between the inner peripheral iron core and the outer peripheral iron core.

  The inner peripheral side iron core has a hole for mounting on the shaft at the center in the axial direction, and is fixed to the shaft by press-fitting the shaft into the hole. The inner peripheral iron core includes a plurality of first protrusions that protrude from the outer peripheral wall toward the outer peripheral iron core on the outer peripheral wall. The plurality of first protrusions extend in the axial direction of the shaft along the outer peripheral wall and are arranged at equal intervals in the circumferential direction.

  The outer peripheral side iron core is fixed with a plurality of permanent magnets extending in the axial direction of the outer peripheral wall and arranged at equal intervals in the circumferential direction. The outer peripheral side iron core is provided with a plurality of second protrusions protruding from the inner peripheral wall toward the inner peripheral side iron core on the inner peripheral wall. The plurality of second protrusions extend in the axial direction of the shaft along the inner peripheral wall and are arranged at equal intervals in the circumferential direction.

  The vibration isolating member is formed in a cylindrical shape having an upper surface and a lower surface with a material having high elasticity (such as rubber or resin), and suppresses vibrations transmitted between the inner peripheral side iron core and the outer peripheral side iron core. The vibration isolating member is filled between the inner peripheral side iron core and the outer peripheral side iron core so as to follow the plurality of first protrusions provided on the inner peripheral side iron core and the plurality of second protrusions provided on the outer peripheral side iron core. . For this reason, the rotational torque of a permanent magnet is transmitted to a shaft, without idling between an inner peripheral side iron core and an outer peripheral side iron core (for example, patent document 1).

  However, the rotor filled with the vibration isolating member between the inner peripheral iron core and the outer peripheral iron core disclosed in Patent Document 1 is transmitted between the inner peripheral iron core and the outer iron core due to the elasticity of the vibration isolating member. While vibration can be suppressed, there is a risk that the coupling strength in the rotation direction of the inner peripheral side iron core, the vibration isolating member, and the outer peripheral side iron core may be insufficient during rotation of the rotor.

Japanese Patent No. 2003-61279

  In view of the above problems, an object of the present invention is to provide a permanent magnet electric motor that can improve the coupling strength in the rotation direction of an inner peripheral side iron core, a vibration isolating member, and an outer peripheral side iron core during rotation of the rotor.

  In order to solve the above problems, a permanent magnet motor of the present invention includes a cylindrical stator and a rotor disposed on the inner peripheral side of the stator, and the rotor has a shaft and a columnar shape fixed to the shaft. An inner peripheral iron core, a cylindrical outer peripheral core disposed around the shaft on the outer peripheral side of the inner peripheral iron core, a plurality of permanent magnets disposed on the outer peripheral side of the outer peripheral core, an inner peripheral iron core, A vibration isolating member filled between the outer peripheral side iron core and the inner peripheral side iron core projecting from the outer peripheral wall toward the outer peripheral side iron core and extending in the axial direction of the shaft along the outer peripheral wall. The permanent magnet motor includes one protrusion, and the outer peripheral iron core includes a plurality of second protrusions that protrude from the inner peripheral wall toward the inner peripheral iron core and extend in the axial direction of the shaft along the inner peripheral wall. , Side walls of a plurality of first protrusions or a plurality of At least one side wall of the second protrusions, vibration isolating members extending in the axial direction of the shaft and having a groove filled. In addition, the sidewalls of the plurality of first protrusions and the sidewalls of the plurality of second protrusions have grooves that extend in the axial direction of the shaft and are filled with vibration-proof members.

  According to the permanent magnet motor of the present invention, it is possible to improve the coupling strength of the inner peripheral side iron core, the vibration isolating member, and the outer peripheral side iron core in the rotation direction when the rotor rotates.

It is sectional drawing which shows the permanent magnet motor of this invention. It is an external appearance perspective view which shows the rotor of the permanent magnet electric motor of this invention. It is a top view which shows the rotor of the permanent magnet electric motor of this invention. It is a longitudinal cross-sectional view equivalent to the AA cross section of FIG. 3 which shows the rotor of the permanent magnet electric motor of this invention. It is a top view which shows the other Example of the rotor of the permanent magnet electric motor of this invention. It is a top view which shows the other Example of the rotor of the permanent magnet electric motor of this invention. It is a top view which shows the other Example of the rotor of the permanent magnet electric motor of this invention. It is a top view which shows the other Example of the groove part formed in the 1st protrusion part of the inner peripheral side iron core in the rotor of this invention, and the 2nd protrusion part of an outer peripheral side iron core.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 to 8 are diagrams for explaining a permanent magnet motor M according to the present embodiment. As shown in FIGS. 1 to 4, this permanent magnet motor M is an inner rotor type motor in which a rotor 2 having a permanent magnet is rotatably arranged inside a stator 1 that generates a rotating magnetic field. The rotor type electric motor includes, for example, a brushless DC motor for rotationally driving a blower fan mounted on an outdoor unit of an air conditioner.

  As shown in FIG. 1, the stator 1 includes a stator core 11 having a cylindrical yoke portion and a plurality of tooth portions extending from the yoke portion toward the inner diameter side, and a winding 13 is wound around the tooth portion via an insulator 12. It has been turned. The stator 1 is covered with a cylindrical motor shell 3 made of resin, except for the inner peripheral surface 111 of the stator core 11 (the inner peripheral surface of the tip of the tooth portion). The rotor 2 is rotatably arranged with a predetermined gap (gap) on the inner peripheral side of the stator core 11 of the stator 1.

  As shown in FIGS. 2 to 4, the rotor 2 is disposed around the shaft on the shaft 21, the cylindrical inner peripheral iron core 22 fixed to the shaft 21, and the outer peripheral side of the inner peripheral iron core 22. A cylindrical outer peripheral core 23, a plurality (eight in this embodiment) of permanent magnets 24 a to 24 h disposed on the outer peripheral side of the outer peripheral core 23, and upper end surfaces of the inner peripheral core 22 and the outer peripheral core 23. An anti-vibration member 25 is provided which covers 22a, 23a and the lower end surfaces 22b, 23b and is filled between the inner peripheral side iron core 22 and the outer peripheral side iron core 23.

  The inner peripheral side iron core 22 has a hole 221 for mounting on the shaft 21 at the center in the axial direction, and is fixed to the shaft 21 by press-fitting the shaft 21 into the hole 221. The inner peripheral side iron core 22 includes a plurality of (four in this embodiment) first protrusions 223 a to 223 d that protrude from the outer peripheral wall 222 toward the outer peripheral side core 23 on the outer peripheral wall 222. The plurality of first protrusions 223a to 223d extend in the axial direction of the shaft 21 along the outer peripheral wall 222 and are arranged at equal intervals in the circumferential direction.

  The outer peripheral side iron core 23 is fixed with a resin 26 (for example, polybutylene terephthalate (PBT)), which extends in the axial direction of the outer peripheral wall 231 and is arranged at equal intervals in the circumferential direction. The outer peripheral side iron core 23 includes a plurality of (four in this embodiment) second protrusions 233a to 233d that protrude from the inner peripheral wall 232 toward the inner peripheral side iron core 22 on the inner peripheral wall 232. The plurality of second protrusions 233a to 233d extend in the axial direction of the shaft 21 along the inner peripheral wall 232 and are arranged at equal intervals in the circumferential direction.

  The plurality of first protrusions 223a to 223d are recessed from the side walls 224a to 224d of the plurality of first protrusions 223a to 223d in the radial direction of the rotor 2 and extend along the side walls 224a to 224d in the axial direction of the shaft 21. ˜225d. The plurality of second protrusions 233a to 233d are recessed from the side walls 234a to 234d of the plurality of second protrusions 233a to 233d in the radial direction of the rotor 2 and extend in the axial direction of the shaft 21 along the side walls 234a to 234d. ˜235d. As shown in FIG. 3, the groove portions 225 a to 225 d and the groove portions 235 a to 235 d are rectangular cut portions and cut portions that are cut from the side walls 224 a to 224 d and the side walls 234 a to 234 d as viewed from above. It is formed in a keyhole shape consisting of a circular hole connected to the tip of the key. The plurality of first protrusions 223a to 223d and the plurality of second protrusions 233a to 233d are disposed so as to face each other with the vibration isolation member 25 interposed therebetween.

  The vibration isolation member 25 is formed in a cylindrical shape having an upper surface 25a and a lower surface 25b with a material having high elasticity (for example, rubber such as chloroprene rubber (CR) or resin such as polybutylene terephthalate (PBT)). The vibration isolation member 25 absorbs and suppresses vibrations transmitted between the inner peripheral side iron core 22 and the outer peripheral side iron core 23.

  The anti-vibration member 25 extends along the outer peripheral wall 222 and the plurality of first protrusions 223a to 223d of the inner peripheral side iron core 22 and the inner peripheral wall 232 and the plurality of second protrusions 233a to 233d of the outer peripheral side iron core 23. It is filled between the inner peripheral side iron core 22 and the outer peripheral side iron core 23. Further, the vibration isolation member 25 is arranged on the inner peripheral side along the groove portions 225a to 225d of the plurality of first protrusion portions 223a to 223d and the groove portions 235a to 235d of the plurality of second protrusion portions 233a to 233d. It is filled between the iron core 22 and the outer peripheral side iron core 23. The anti-vibration member 25 is filled so as to cover the upper surface 22a and the lower surface 22b of the inner peripheral side iron core 22 and the upper surface 23a and the lower surface 23b of the outer peripheral side iron core 23 in order to prevent the shaft 21 from coming off in the axial direction. . For this reason, by providing the rotor 2 with the vibration isolation member 25, the rotational torque of the plurality of permanent magnets 24 a to 24 h is transmitted to the shaft 21 without idling between the inner peripheral side iron core 22 and the outer peripheral side iron core 23. The

  In the rotor 2 configured in this manner, first, the plurality of permanent magnets 24 a to 24 h are arranged around the outer peripheral wall 231 of the outer peripheral side iron core 23, and the plurality of permanent magnets 24 a to 24 h are made of the outer peripheral side iron core 23 by the resin 26. The outer peripheral wall 231 is fixed. Further, the shaft 21 is press-fitted into the hole 221 of the inner peripheral iron core 22, and the shaft is fixed to the inner peripheral iron core 22. Next, the outer peripheral side iron core 23 to which the plurality of permanent magnets 24a to 24h are fixed, and the inner peripheral side iron core 22 to which the shaft 21 is fixed, the plurality of first protrusions 223a to 223d and the plurality of second protrusions. It arrange | positions in a metal mold | die so that 233a-233d may each oppose.

  Finally, the material of the vibration isolating member 25 is poured between the outer peripheral side iron core 23 and the inner peripheral side iron core 22 arranged in the mold to fill the vibration isolating member 25. At this time, the vibration isolator 25 includes the groove portions 225a to 225d of the plurality of first protrusion portions 223a to 223d, the groove portions 235a to 235d of the plurality of second protrusion portions 233a to 233d, and the upper surface 23a of the outer peripheral side iron core 23. The lower surface 23b and the upper surface 22a and the lower surface 22b of the inner peripheral iron core 22 are also filled. As a result, the rotor 2 is assembled as shown in FIG.

  According to the permanent magnet motor M according to the present embodiment described above, the plurality of first protrusions 223a to 223d and the plurality of second protrusions 233a to 233d are the side walls 224a to 223a to 223d of the plurality of first protrusions 223a to 223d. Grooves 225a to 224d are filled with vibration isolation members 25 that are recessed from the side walls 234a to 234d of the plurality of second protrusions 233a to 233d and extend along the side walls 224a to 224d and the side walls 234a to 234d in the axial direction of the shaft 21. 225d and grooves 235a to 235d. As a result, when the vibration isolating member 25 is filled between the inner peripheral side iron core 22 and the outer peripheral side iron core 23, the vibration isolating member 25 is sufficiently spread (flowed) into the groove portions 225a to 225d and the groove portions 235a to 235d, The vibration isolation member 25 can be reliably filled.

  Further, the vibration isolation member 25 is connected to the inside of the groove portions 225a to 225d and the groove portions 235a to 235d from the upper surface 22a and the lower surface 22b side of the inner peripheral side iron core 22 and the upper surface 23a and the lower surface 23b side of the outer peripheral side iron core 23. Can do. And compared with the case where there is no groove part 225a-225d and groove part 235a-235d, the contact part of the inner peripheral side iron core 22, the vibration isolator member 25, and the outer peripheral side iron core 23, and the vibration isolator member 25 are the upper surfaces of the inner periphery side iron core 22 Since the portion connected from the side of 22a and the lower surface 22b and the side of the upper surface 23a and the lower surface 23b of the outer peripheral side core 23 can be increased, the inner peripheral side iron core 22, the vibration isolating member 25 and the outer peripheral side iron core are rotated during the rotation of the rotor 2. It is possible to improve (strengthen) the bonding strength in the rotational direction of 23.

  In the permanent magnet motor M according to the present embodiment, the plurality of first protrusions 223a to 223d have the grooves 225a to 225d, and the plurality of second protrusions 233a to 233d have the grooves 235a to 235d. However, the present invention is not limited to this, and as shown in FIG. 5, only the plurality of second protrusions 233 a to 233 d may have a groove 235 a to 235 d, and as shown in FIG. Only one protrusion 223a to 223d may have a structure having grooves 225a to 225d. In the embodiment shown in FIG. 5 and FIG. 6 as well, when the vibration isolating member 25 is filled between the inner peripheral side iron core 22 and the outer peripheral side iron core 23, the groove portions 225a to 225d or the groove portions 235a to The anti-vibration member 25 can be sufficiently spread (inflowed) to 235d, and the anti-vibration member 25 can be reliably filled.

  In addition, as illustrated in FIG. 7, the first protrusions 223a and 223c among the plurality of first protrusions 223a to 223d have grooves 225a and 225c, and the plurality of second protrusions 233a to 233d includes the first The two protrusions 233b and 233d may have a groove 235b and 235d. In this case, the grooves 225a and 225c of the first protrusions 223a and 223c and the grooves 235b and 235d of the second protrusions 233b and 233d are alternately arranged in the rotation direction. In the embodiment shown in FIG. 7 as well, the groove portions 225a and 225c and the groove portions 235b and 235d are prevented when the vibration isolating member 25 is filled between the inner periphery side iron core 22 and the outer periphery side iron core 23, as in the above-described embodiment. The vibration member 25 can be sufficiently spread (inflowed) to reliably fill the vibration isolation member 25.

  FIG. 8A to FIG. 8E show another embodiment of the groove portions 225a to 225d included in the plurality of first protrusion portions 223a to 223d and the groove portions 235a to 235d included in the plurality of second protrusion portions 233a to 233d. Show. In FIGS. 8A to 8E, only the groove 225c included in the first protrusion 223c and the groove 235c included in the second protrusion 233c are illustrated, and the other grooves are omitted.

  In the permanent magnet motor M according to the present embodiment, the plurality of first protrusions 223a to 223d and the plurality of second protrusions 233a to 233d are recessed in the radial direction of the rotor 2 from the side walls 224a to 224d and the side walls 234a to 234d. Although it has the structure which has the groove parts 225a-225d and the groove parts 235a-235d which extend along the side walls 234a-234d in the axial direction of the shaft 21, this invention is not limited to this, FIG. 8 (a) and FIG. 8 (b). As shown, the plurality of first protrusions 223a to 223d and the plurality of second protrusions 233a to 233d are grooves 225a to 225d and grooves 235a that are recessed from the side walls 224a to 224d and the side walls 234a to 234d in the rotation direction of the rotor 2. A structure having ˜235d may be used. As shown in FIG. 8 (a), the groove portions 225a to 225d and the groove portions 235a to 235d are recessed in the same rotation direction, but as shown in FIG. 8 (b), the groove portions 225a to 225d and the groove portions 235a to 235a to The 235d may be recessed in opposite rotation directions.

  Furthermore, in the permanent magnet motor M according to the present embodiment, the groove portions 225a to 225d included in the plurality of first protrusion portions 223a to 223d and the groove portions 235a to 235d included in the plurality of second protrusion portions 233a to 233d are viewed from above. However, the present invention is not limited to this, and as shown in FIGS. 8B and 8D, the grooves 225a to 225d and the grooves 235a to 235d are respectively viewed from the top. It may be formed in a square shape. Moreover, as shown in FIG.8 (c), you may make groove part 225a-225d and groove part 235a-235d into a U-shape, and as shown in FIG.8 (e), groove part 225a-225d and groove part 235a- 235d may be triangular.

M Permanent magnet motor 1 Stator 11 Stator core 12 Insulator 13 Winding 2 Rotor 21 Shaft 22 Inner peripheral iron core 22a Upper surface 22b Lower surface 221 Hole 222 Outer peripheral wall 223a to 223d First protrusion 224a to 224d Side wall 225a to 225d Groove 23 Outer peripheral core 23a upper surface 23b lower surface 231 outer peripheral wall 232 inner peripheral wall 233a to 233d second protrusion 234a to 234d side wall 235a to 235d groove 24a to 24h permanent magnet 25 vibration isolator 25a upper surface 25b lower surface 26 resin 3 motor outer shell

Claims (2)

A cylindrical stator, and a rotor disposed on the inner peripheral side of the stator,
The rotor includes a shaft, a cylindrical inner peripheral iron core fixed to the shaft, a cylindrical outer peripheral core disposed around the shaft on the outer peripheral side of the inner peripheral core, and the outer peripheral side. A plurality of permanent magnets arranged on the outer peripheral side of the iron core, and a vibration isolating member filled between the inner peripheral side iron core and the outer peripheral side iron core,
The inner peripheral iron core includes a plurality of first protrusions that protrude from the outer peripheral wall toward the outer peripheral iron core and extend in the axial direction of the shaft along the outer peripheral wall.
The outer peripheral side iron core is a permanent magnet electric motor provided with a plurality of second protrusions that protrude from the inner peripheral wall toward the inner peripheral side iron core and extend in the axial direction of the shaft along the inner peripheral wall.
At least one of the side walls of the plurality of first protrusions or the side walls of the plurality of second protrusions has a groove that extends in the axial direction of the shaft and is filled with the vibration isolation member. Electric motor. A cylindrical stator, and a rotor disposed on the inner peripheral side of the stator,
The rotor includes a shaft, a cylindrical inner peripheral iron core fixed to the shaft, a cylindrical outer peripheral core disposed around the shaft on the outer peripheral side of the inner peripheral core, and the outer peripheral side. A plurality of permanent magnets arranged on the outer peripheral side of the iron core, and a vibration isolating member filled between the inner peripheral side iron core and the outer peripheral side iron core,
The inner peripheral iron core includes a plurality of first protrusions that protrude from the outer peripheral wall toward the outer peripheral iron core and extend in the axial direction of the shaft along the outer peripheral wall.
The outer peripheral side iron core is a permanent magnet electric motor provided with a plurality of second protrusions that protrude from the inner peripheral wall toward the inner peripheral side iron core and extend in the axial direction of the shaft along the inner peripheral wall.
A permanent magnet electric motor comprising grooves on the side walls of the plurality of first protrusions and the side walls of the plurality of second protrusions that extend in the axial direction of the shaft and are filled with the vibration isolation member.

Images