| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for preventing single-phase motor reverse rotation by which a single-phase motor can be prevented from reversely rotating and running out of control when an excessive load is applied thereto. <P>SOLUTION: The method is for preventing the reverse rotation of a single-phase motor with an auxiliary winding, the single-phase motor being a split-phase-start type one having an auxiliary winding for start, or a capacitor-start-and-capacitor-induction type one having a starting capacitor for start. The method comprises the steps of: after the power-on (S1), energizing the auxiliary winding for start (in the case of the split-phase-start type) or the starting capacitor (in the case of the capacitor-start-and-capacitor-induction type) for a predetermined length of time (S5); thereafter detecting an induced voltage developing across the auxiliary winding; judging whether the detected induced voltage is below a predetermined voltage or not (S13); and if the induced voltage is judged as being below the predetermined voltage (S13), energizing the auxiliary winding for start (in the case of the split-phase-start type) or the starting capacitor (in the case of the capacitor-start-and-capacitor-induction type) for a length of time longer than that required for judgment (S19) on whether an excessive current flows in the single-phase motor or not (S17). <P>COPYRIGHT: (C)2012,JPO&INPIT |
