Brushless motor apparatus
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorToru Kawabata
Life of this patent
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Abstract
A brushless motor apparatus includes a motor section including delta-connected three-phase coils; a switching section electrically connected to the motor section via a line; and a driving section for controlling an ON state and an OFF state of the switching section so as to drive the motor section. In the brushless motor apparatus, r1+r2<2R, where r1 is an internal resistance of the switching section in an ON state, r2 is a resistance of the line connecting the motor section and the switching section, and R is a direct current resistance of each of the three-phase coils.
Claims5
A brushless motor apparatus, comprising:
- a motor section including delta-connected three-phase coils;
- a switching section electrically connected to the motor section by a line;
- and
- a driving section for controlling an ON state and an OFF state of the switching section so as to drive the motor section with a driving current;
- wherein r1+r2<2R, where r1 is an internal resistance of the switching section in an ON state, r2 is a resistance of the line connecting the motor section and the switching section, and R is a direct current resistance of each of the three-phase coils,
- wherein the driving section comprises a read start position varying section for varying the phase of the driving current in accordance with the rotation speed of the motor.
Dependencies are inferred from the claim text.