Patent ID: 8207745

Claim:
An anomaly monitoring device for detecting anomalies in an encoder or a wiring system, in which output signals from the encoder which detects the position of a rotation member are input as analog input signals to a control device via the wiring system comprising a power supply line and a signal line, and the control device processes the analog input signals and detects anomalies in the encoder or the wiring system, the anomaly monitoring device comprising: a converting device configured to convert voltage level input signals, which are obtained from the analog input signals, into first digital signals; a voltage level based device configured to detect anomalies in the encoder or the wiring system based on the voltage level of the analog input signals measured from the first digital signals; a pulse number based device configured to detect anomalies in the encoder or the wiring system based on the number of pulses of second digital signals which are obtained by converting at least two of the analog input signals; and a pulse width based device configured to detect anomalies in the encoder or the wiring system based on the pulse widths of third digital signals which are obtained from the second digital signals.