JPS6420954A - Numerically controlled machine tool - Google Patents

Abstract

PURPOSE:To avoid a memory as the machining program when erroneous commands exceeding the machining region are issued by storing the coordinate values read at the time of machining only when they are in the preset region before the machining and stopping the movement of a main shaft when they are outside the region. CONSTITUTION:The machining region is set by a worker via a data input unit 25, if the input of the coordinate position is not completed, signals outputted by the operation of pulse generators 26X-26Z of an operation panel 26 for the coordinate position memory are entered to an arithmetic processing unit 21 then to an NC program arithmetic processing unit 31 by a skilled worker, and commands corresponding to the output signals from the unit 31 are sent to motor driving circuits DUX-DUZ. Pulses are distributed to motors 51-53, a main shaft 56 is axially moved, a work W on a table 54 is machined by a tool T, coordinate positions of center positions P0-Pn of the tool T with the radius R are read from position detectors 61-63, whether the coordinate values of the read present position Pn(Xn, Yn, Zn) are within the machining region or not is judged, even if one axis is outside the machining region, the moving motors of the main shaft 56 are stopped.