| 摘要 |
<p>BRUSHLESS DIRECT CURRENT MOTOR WITH MAGNETICALLY OPERATED COMMUTATING SWITCH MEANS Current to the stator coils of a brushless DC motor is commutated by making transistors alternately conductive by current through magnetically actuated switches. These switches are actuated by magnetic fields from the permanently magnetized poles of a magnet attached to, but spaced from the rotor and the stator poles. Depending on the polarity of the magnetic fields, the switches permit one of the transistors to be biased by a voltage source that causes that transistor to become conductive and, simultaneously, connects the base of the other transistor to a voltage that causes that transistor to become non-conductive. Conductivity of the transistors alternates as the rotor rotates.</p> |
