Patent ID: 7454256

Claim:
An NC device for numerically controlling a machine in accordance with an NC machining program, the device comprising: an accumulation portion for accumulating a report-item corresponding to a report-requiring situation that occurs in the machine, wherein the report-requiring situation is at least one of a situation in which a machining problem occurs in the machine and a situation for requiring an operator to generate an instruction for a subsequent operation for the machine; a voice generator for generating a voice; a voice generator control section for controlling the voice generator; a determination portion for determining whether or not operator-in-range information has been generated for indicating that the operator is located in an audible range of the voice generated by the voice generator when the report requiring situation occurs in the machine; and a request portion for requesting generation of the voice when the request portion is manipulated by the operator or in response to detection of the operator in the audible range; wherein the voice generator control section operates the voice generator to generate the voice for announcing the report-item accumulated by the accumulation portion if the determination portion determines that the operator-in-range information has been generated or in response to a request produced by the request portion but does not permit the voice generator to generate the voice if the determination portion determines that the operator-in-range information has not been generated; wherein the voice generator control section does not permit the voice generator to generate the voice if the accumulation portion does not accumulate the report-item.