PURPOSE: To detect the inversion failure in rotary direction of a completed product of a motor due to the improper connection of a stator coil by a stator only.
CONSTITUTION: Current is fed to a main coil 13 and a sub coil 14 of a stator 11 to be inspected by a 90-degree phase biphase power supply 12. The leakage magnetic flux generated by the current is detected by magnetic flux detectors 15 and 16. The detection signal has a 90-degree phase difference and the advance/delay of the phase are inverted depending on the rotary direction. Therefore, by judging the advance/delay of phase using a rotary direction (phase) detector 17 based on the detection signal, the rotary direction can be simply detected by a single stator without any drive part such as a pseudo rotor and without inserting the pseudo rotor into the stator.
MURAKAMI HIROSHI
TSUBOKAWA MASAHIRO
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