Abstract: An encoder system includes an encoder for outputting positional data and magnetic pole data of an output axis of a motor; and a controller for communicating with the encoder. The encoder includes a positional data generation circuit; a magnetic pole data generation circuit; a first data abnormality detection circuit for detecting an abnormality based on the positional data and the magnetic pole data, and outputting a first alarm signal; and a parallel-to-serial conversion circuit for outputting the positional data, the magnetic pole data, and the first alarm signal to the controller. The controller includes a second data abnormality detection circuit for detecting an abnormality based on the positional data and the magnetic pole data, and outputting a second alarm signal; and a communication abnormality detector for detecting an abnormality in a communication path based on the first and second alarm signals.

Abstract: An encoder system includes an encoder for outputting positional data and magnetic pole data of an output axis of a motor; and a controller for communicating with the encoder. The encoder includes a positional data generation circuit; a magnetic pole data generation circuit; a first data abnormality detection circuit for detecting an abnormality based on the positional data and the magnetic pole data, and outputting a first alarm signal; and a parallel-to-serial conversion circuit for outputting the positional data, the magnetic pole data, and the first alarm signal to the controller. The controller includes a second data abnormality detection circuit for detecting an abnormality based on the positional data and the magnetic pole data, and outputting a second alarm signal; and a communication abnormality detector for detecting an abnormality in a communication path based on the first and second alarm signals.

Abstract: An encoder having a function for detecting noise which may affect an internal signal of the encoder, without using a noise detecting circuit within the encoder, whereby the cost and size thereof may be reduced. The encoder has a detecting part adapted to detect the movement of an electric motor or a driven object; a signal processing circuit adapted to process a detection signal from the detecting part and obtain positional data of the motor or the object; and a transmitting part adapted to transmit the positional data from the signal processing circuit at regular time intervals and a fluctuation component calculated on the basis of the positional data, to external equipment. The signal processing circuit has a fluctuation component detecting circuit adapted to detect a fluctuation comment included in the calculated positional data, and the detected fluctuation component is transmitted to the external controller as an amount of noise.

Abstract: An encoder having a function for detecting noise which may affect an internal signal of the encoder, without using a noise detecting circuit within the encoder, whereby the cost and size thereof may be reduced. The encoder has a detecting part adapted to detect the movement of an electric motor or a driven object; a signal processing circuit adapted to process a detection signal from the detecting part and obtain positional data of the motor or the object; and a transmitting part adapted to transmit the positional data from the signal processing circuit at regular time intervals and a fluctuation component calculated on the basis of the positional data, to external equipment. The signal processing circuit has a fluctuation component detecting circuit adapted to detect a fluctuation comment included in the calculated positional data, and the detected fluctuation component is transmitted to the external controller as an amount of noise.

Abstract: A center voltage of an analog signal from a magnetic sensor is measured to match a reference voltage with the center voltage. Then, a combination of portions to be disconnected of adjustment patterns 1 and 2 of adjustment circuits 1 and 2 is determined so that the reference voltage is adjusted to the measured center voltage, and the portions are disconnected. The adjustment circuits 1 and 2 respectively include recovery patterns 1 and 2. If an adjustment pattern 1 and 2 is erroneously disconnected, the corresponding recovery pattern 1 and 2 is short-circuited by means of soldering or the like to short-circuit the adjustment pattern 1 and 2 once again.

Abstract: After cyclic original signals generated from a sensing element of an encoder are converted into digital signals, positions P(0) to P(n) in one period are obtained for each given period by means of a digital interpolator. If position data obtained immediately after a zero cross point is detected are P(0) and P(n) and if speed is fixed, an object should move on a straight line from a position P(0) to a position P(n). An actual detected position data P(m) is deviated from this straight line by D(m). This detection error D(m) and the detected position data P(m) are combined and stored in advance as reference data, and correction is carried out using the reference data every time position data is detected by the digital interpolator.

Abstract: After cyclic original signals generated from a sensing element of an encoder are converted into digital signals, positions P(0) to P(n) in one period are obtained for each given period by means of a digital interpolator. If position data obtained immediately after a zero cross point is detected are P(0) and P(n) and if speed is fixed, an object should move on a straight line from a position P(0) to a position P(n). An actual detected position data P(m) is deviated from this straight line by D(m). This detection error D(m) and the detected position data P(m) are combined and stored in advance as reference data, and correction is carried out using the reference data every time position data is detected by the digital interpolator.

Abstract: Amplifiers connected to a CNC are provided individually with memories that are stored with ID data for discriminating the kinds and properties thereof and ID data as maintenance management data. Likewise, motors are provided with memories stored with ID data. The management of the amplifiers and the motors is facilitated by reading these ID data from the CNC and displaying them on a display unit. Based on the ID data, moreover, adaptation or nonadaptation between the motors and the amplifiers is automatically determined by means of the CNC.

Abstract: Amplifiers (41 to 44) connected to a CNC (10) are provided individually with memories (41b to 44b) that are stored with ID data for discriminating the kinds and properties thereof and ID data as maintenance management data. Likewise, motors (41c to 44c) are provided with memories (41c to 44c) stored with ID data. The management of the amplifiers and the motors is facilitated by reading these ID data from the CNC (10) and displaying them on a display unit (20). Based on the ID data, moreover, adaptation or nonadaptation between the motors and the amplifiers is automatically determined by means of the CNC (10).

Abstract: A motor controller for controlling currents flowing to a motor by the PWM system includes interruption-restart controller for interrupting supply of PWM commands for at least one phase when the actual current flowing in at least one motor phase has exceeded a specified value, and for thereafter restarting PWM command supply. When the actual current flowing to the motor has reached a previously determined anomalous level, control is performed to interrupt and restart supply of PWM commands. By interrupting the supply of the PWM commands, the current flowing to the motor is returned from an anomalous level to a normal level and the equipment protected. After the motor current is returned to a normal level by the interruption of PWM command supply, PWM command supply is resumed, normal control by PWM command is again performed, and a non-controlling state in the controller is avoided.