PERMANENT MAGNET MOTOR

• US 20110241467A1
• Filed: 03/24/2011
• Published: 10/06/2011
• Est. Priority Date: 03/31/2010
• Status: Abandoned Application

• Current Assignee: Fujitsu General Company Limited (Fujifilm Holdings Corporation)
• Original Assignee: Fujitsu General Company Limited (Fujifilm Holdings Corporation)
• Inventors: SUZUKI, Shingo, KATAGIRI, Shinichiro, TANABE, Yoichi, HAMANO, Takuya, FUJIOKA, Takushi
• Application Number:
  US13/071,297
• Publication Number:
  US 20110241467A1
• Time in Patent Office: Days
• US Class Current: 310/156.08
• CPC Class Codes: H02K 1/146 consisting of a generally annular yoke with salient poles
• CPC Class Codes: H02K 1/278 Surface mounted magnets; Inset magnets

Abstract

A permanent magnet motor is provided. The permanent magnet motor includes: a stator including a stator core, and an insulator for insulating the stator core from the wire; and a rotor in which a rotating shaft is attached to a center of the rotor and a permanent magnet is provided in an outer peripheral portion of the rotor. The stator core includes an annular yoke portion, a plurality of teeth extended radially from an inner periphery of the yoke portion, and a plurality of slots for accommodating a wire to be wound around the teeth at both ends in a circumferential direction of the teeth. A number of the slots in the stator core is set to be 18, the permanent magnet of the rotor is formed by a ferrite magnet, and a number of poles of the permanent magnet is set to be 12.

Claims

1. A permanent magnet motor comprising:

a stator including a stator core, and an insulator for insulating the stator core from the wire; and

a rotor in which a rotating shaft is attached to a center of the rotor and a permanent magnet is provided in an outer peripheral portion of the rotor,

wherein the stator core includes an annular yoke portion, a plurality of teeth extended radially from an inner periphery of the yoke portion, and a plurality of slots for accommodating a wire to be wound around the teeth at both ends in a circumferential direction of the teeth, and

wherein a number of the slots in the stator core is set to be 18, the permanent magnet of the rotor is formed by a ferrite magnet, and a number of poles of the permanent magnet is set to be 12.

2. The permanent magnet motor according to claim 1, wherein a torque of 1 Nm or less and a rotating speed of 2000 rpm or less are set into a drive enabling range,

the following expression being obtained:

T≦

7.68×

10<sup>−

6</sup>NL+2.40×

10<sup>−

3</sup>L

wherein a torque of the permanent magnet motor is represented by T, a rotating speed is represented by N, and a length in a direction of a rotating shaft of the stator core is represented by L.

3. The permanent magnet motor according to claim 1, wherein the permanent magnet is a ferrite bond magnet which is molded by mixing a ferrite magnetic substance into a resin material, and a magnetic field orientation of the ferrite bond magnet is set to be a polar anisotropic orientation.

4. The permanent magnet motor according to claim 2, wherein the permanent magnet is a ferrite bond magnet which is molded by mixing a ferrite magnetic substance into a resin material, and a magnetic field orientation of the ferrite bond magnet is set to be a polar anisotropic orientation.