Industrial machine having abnormal vibration detecting function

摘要

An industrial machine in which vibration exerted on a position detector provided for an axis of the machine is detected and countermeasures against the vibration can be swiftly taken. A ball screw is driven by a servo motor MZ supplied with power from a servo amplifier via a power line so that a cutting unit is advanced and retracted. A spindle motor MS above the cutting unit rotates a cutting tool via a spindle shaft and a workpiece W on an XY table is machined. An acceleration detection element is built in a position detector attached to a motor shaft of the servo motor MZ. An angle detection signal for servo control and a vibration level signal outputted by the acceleration detection element are converted into serial signals and are transmitted to a controller (axis control circuit of Z-axis) via the common signal line. The controller takes measures of changing the machining condition (for example, change of spindle rotational speed) and stopping the machine in accordance with a rank of the vibration. A duration or total time period of the abnormal vibration may be monitored.