Patent ID: 7595602
Filing Date: 2009-09-29
Classification: G05B

Abstract:
1. A machine tool comprising: a machine base; a workpiece holder supported by the machine base; at least one spindle to which at least one cutting tool is fixedly secured; a plurality of servo motors; at least one spindle motor capable of rotating the at least one spindle; a computer numerical control (CNC) capable of directing the operation of the servo motors to control movement of the workpiece relative to the cutting tool; the CNC further capable of directing the operation of the spindle motor to control a current spindle rotational speed; and a feedrate control apparatus for controlling a feedrate of the workpiece relative to the cutting tool, the apparatus capable of receiving spindle parameter data, the spindle parameter data comprising a plurality of spindle parameter limits and a plurality of corresponding spindle rotational speeds; the apparatus further capable of receiving a current spindle value and the current spindle rotational speed; the apparatus configured to determine a respective spindle parameter limit by interpolating between the spindle parameter limits of the spindle parameter data based upon a relationship of the current spindle rotational speed to the corresponding spindle rotational speeds of the spindle parameter data, the apparatus further capable of comparing the current spindle value to the respective spindle parameter limit; and the apparatus further capable of adjusting the feedrate of the machine tool based on the comparison between the current spindle value and the respective spindle parameter limit.