MOVEMENT PRECISION MONITORING SYSTEM AND ROTATION TABLE PROVIDED WITH MOVEMENT PRECISION MONITORING FUNCTION, MACHINE TOOL AND NC APPARATUS

摘要

To provide a movement precision monitoring system capable of appropriately monitoring and diagnosing a reduction in movement precision in an actual operation in a timely manner.SOLUTION: A movement precision monitoring system 2 includes: a drive-shaft-side sensor 10 that measures a position or displacement of a drive shaft 4 which is rotated and moved; a driven-unit-side sensor 12 that measures a position or displacement of a driven unit 6 which is rotated or moved on a predetermined trajectory by drive torque from the drive shaft 4 via a drive force transmitting unit 8; a differential detecting unit 22 that forms differential data between the displacement of the drive shaft 4 and the displacement of the driven unit 6 having a transmission gear ratio of the drive force transmitting unit 8 taken into consideration on the basis of measured values of the drive-shaft-side sensor 10 and of the driven-unit-side sensor 12 at a timing defined in a predetermined manner; and a monitoring control unit 24 that forms information on a movement precision of the driven unit 6 on the basis of a change in the differential data or a change in computed value using the differential data. A rotation table provided with a movement precision monitoring function, a machine tool and an NC apparatus are also provided.SELECTED DRAWING: Figure 3