DAMAGE DETECTING DEVICE FOR SUPPORTING STRUCTURE FOR ARMATURE SHAFT

摘要

A damage detecting device according to one aspect of the present invention comprises a first speed generator, a second speed generator, a first waveform shaping section, a second waveform shaping section, and a determining section. The determining section compares a second rectangular wave shaped by the second waveform shaping section and a first rectangular wave shaped by the first waveform shaping section and, if the first rectangular wave is not output while the second rectangular wave is output, determines that a supporting device for an armature shaft is damaged or worn.

主权项

1. A damage detecting device that detects damage to a supporting device rotatably supporting an armature shaft of an electric motor, the device comprising:
a first speed generator; and a second speed generator; wherein the first speed generator comprises: a disk-shaped first inductor attached to the armature shaft, and having recesses and projections formed at equal pitches along a circumference around a same central axis as the armature shaft; at least one pair of first magnetic pole pieces, one end of each of the first magnetic pole pieces being joined to one of poles of a first permanent magnet, and the other end of each of the first magnetic pole pieces being disposed opposite the recesses and projections of the first inductor; and a first coil that detects a change in a magnetic flux passing through the first magnetic pole pieces and generates an output voltage of a waveform corresponding to this detection; and wherein the second speed generator comprises: a disk-shaped second inductor attached to an axle of a driving wheel shaft to which power from the electric motor is transmitted via the armature shaft, and having recesses and projections formed at equal pitches along a circumference around a same central axis as the axle; at least one pair of second magnetic pole pieces, one end of each of the second magnetic pole pieces being joined to one of poles of a second permanent magnet, and the other end of each of the second magnetic pole pieces being disposed opposite the recesses and projections of the second inductor; and a second coil that detects a change in a magnetic flux passing through the second magnetic pole pieces and generates an output voltage of a waveform corresponding to this detection; the device further comprising: a first waveform shaping section that converts the output voltage, generated in the first coil, into a first rectangular wave based on a preset first threshold value; a second waveform shaping section that shapes the output voltage, generated in the second coil, into a second rectangular wave based on a preset second threshold value; and a determining section that compares the second rectangular wave and the first rectangular wave and determines, if the first rectangular wave is not output while the second rectangular wave is output, that the supporting device is damaged or worn.