Patent ID: 11886205
Assignee: FANUC CORPORATION
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G

Claim 0:
1. A servo motor controller that detects Z-phase signals of an incremental-type encoder that detects rotation of a servo motor to perform driving control of the servo motor, comprising:
a position detection unit that detects a reference position of a rotating shaft of the servo motor on the basis of the Z-phase signal of the encoder;
a signal interval detection unit that measures intervals of a plurality of detected Z-phase signals;
an abnormality determination unit that determines that the Z-phase signal is abnormal when the interval measured by the signal interval detection unit is equal to or larger than a prescribed threshold; and
a speed changing unit that changes a speed of the servo motor, wherein
the speed changing unit changes the speed of the servo motor when the abnormality determination unit determines that the Z-phase signal is abnormal.