Automatic centering controller for a machine tool

摘要

An automatic centering controller for centering the axis of a tool spindle of a numerically controlled machine tool on the axis of a reference circumferential surface of an article mounted on the machine tool. The controller comprises a touch sensing device mounted in the tool spindle for detecting the touch of a probe thereof with the reference circumferential surface, a pulse generator for applying feed pulses to servomotors through a numerical controller so as to move the tool spindle along X and Y-axes, and a pulse control device connected to the touch sensing device, the numerical controller and the pulse generator. In response to a centering instruction and the touch signal, the pulse control device applies axis designation signals to the numerical controller being under a manual mode and controls the feed pulses applied to the numerical controller so that the tool spindle is first moved along the X-axis so as to position the axis of the tool spindle at the median between two points where the probe touches with the reference circumferential surface on the X-axis and is then moved along the Y-axis so as to position the axis of the tool spindle at the median between two points where the probe touches with the reference circumferential surface on the Y-axis.