Method of and apparatus for finely machining a workpiece with numerical control having a computer-aided simulated function

An apparatus for finely machining a workpiece with use of a numerical control having a computer-aided simulation function, said apparatus comprising:

• an NC machine having a machine tool for machining a workpiece;
• a drive means mounted in said NC machine for driving said machine tool;
• an NC control means for controlling said drive means;
• a control shell for collectively controlling said machine tool, said drive means, and said NC control means, and for simulating a machining status during machining to predict a result of machining, determining whether or not the result of the simulating is within a permissible range obtaining information on another machine tool from a data base if the result of the simulating is not within the permissible range preparing machining commands based on the machining program and the result of the simulating, and executing an NC control based on the machining commands to optimize a remainder of machining;
• and
• a display and instruction device for selectively displaying design data obtained by CAD, machining conditions, a machining program, machining status information obtained from a start of machining up to a present time at a machining site, the result of the simulating executed by said control shell, and instructions given to said control shell, wherein the machining status information includes at least one of sound information obtained from the machining site, information indicative of a drive current required to drive said NC machine, information indicative of a shape of the workpiece, and information indicative of a shape of said machine tool;
• wherein said control shell further controls said display and instruction device.

A method for machining a workpiece at a machining site using an NC machine and a machine tool, said method comprising:

• preparing a machining program based on CAD data and machining conditions stored in a database;
• generating numerical control data based on said machining program;
• controlling machining of the workpiece according to said numerical control data using the NC machine;
• obtaining, during said controlling of the machining, actual machining status information from the machining site;
• determining whether said actual machining status information is within a permissible range;
• continuing said controlling of the machining according to said numerical control data if said actual machining status information is determined to be within the permissible range;
• and
• performing a modification procedure if said actual machining status information is determined not to be within the permissible range;
• wherein said modification procedure includes
• generating simulated machining status information by performing a machining simulation based on said machining program and a modification of said actual machining status information,
• determining whether said simulated machining status information is within the predetermined range,
• if said simulated machining status information is determined to be within the predetermined range, generating new numerical control data based on said machining program and said simulated machining status information and continuing said controlling of the machining according to said new numerical control data, and
• if said simulated machining status information is determined not to be within the predetermined range, repeating said modification procedure based on a further modification of said actual machining status information until said simulated machining status information is within the predetermined range.