AUTOMATIC CUTTING-TOOL CONDITION MONITORING ON CNC LATHES

This paper addresses the problem of automatically defining cutting-too l wear on CNC lathes. The problem is solved by analysing the axial for ce during the pressing of the cutting edge of an insert into the workp iece while the cutting process is stopped. During machining the feed m ovement is interrupted and the position of the cutting tool at this mo ment becomes a reference point. With no feed movement the rotation of the workpiece continues for a few revolutions, the cutting edge being moved off the transient surface in the axial direction, after which th e rotation stops. With slow axial movement the cutting edge is pressed into the surface of the workpiece and at the same time the pressing d epth relative to the reference point and the axial force are measured. Analysis of the results shows a close relationship between the axial force, measured ata fixed pressing depth and the flank wear of the cut ting tool. The paper also presents some results on cutting-tool condit ion monitoring using artificial neural networks. (C) 1998 Elsevier Sci ence S.A. All rights reserved.