Motor structure

• Main Authors: AKAOKA, HIROKI, FUJITANI, SAKAE, SUZUKI, YUZURU
• Format: Patent
• Language: English; French; German
• Published: 04.06.1997
• Edition: 6
• Subjects: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORSOR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; DYNAMO-ELECTRIC MACHINES; ELECTRICITY; GENERATION

This invention provides a two-phase motor which is applicable to a field where high rotation precision is required as in an FDD spindle motor, which requires a low cost, and which can maintain stable characteristics free from magnetic balance fluctuation between the two phases due to assembly. This motor has a ferromagnetic stator having N stator salient poles and a rotor magnet having M poles. N and M are selected to be both even numbers so a relation N:M = 2:2n - 1 (n is a natural number) holds. The N stator salient poles are divided into first and second salient pole groups of N/2 stator salient poles on which windings are concentratedly wound. The stator salient poles belonging to the first and second salient pole groups are alternately arranged in the circumferential direction of the stator. The phases of the windings of the stator salient poles belonging to the first and second salient pole groups are sequentially opposite to each other in the circumferential direction in units of groups. The windings of the stator salient poles belonging to the first and second salient pole groups are sequentially, electrically connected in the circumferential direction in units of groups to respectively form first and second phases, thereby providing a two-phase arrangement.