Numerical controller, numerical control machine tool, machining program generation device, and machining program generation method

A numerical control machine tool that includes a drive mechanism provided for each of a plurality of axes, includes a mechanical structure to perform motion by power that is transmitted from the drive mechanism, and machines a workpiece using a tool attached to the mechanical structure, the numerical control machine tool comprising:

• model holding circuitry that holds a machine model, the machine model being a model that simulates deformation of the mechanical structure accompanying the motion of the mechanical structure in axial directions and representing an error amount as an amount of displacement of the tool in the axial directions due to the deformation of the mechanical structure, the axial directions being directions of corresponding ones of the plurality of the axes;
• machining error estimation circuitry to estimate an error direction and the error amount in the error direction on the basis of axis data that is data on drive of the drive mechanism and the machine model, and output machining error information indicating the error direction estimated and the error amount estimated, the error direction being a direction different from a direction of the motion of the mechanical structure among the axial directions and being a direction in which displacement of the tool occurs;
• and
• correction amount arithmetic circuitry to select one or more of the axes subject to correction on the basis of the machining error information, and perform arithmetic to find a correction amount that is used for correction of a command to be output to the drive mechanism for the axis selected, wherein
• the machine model is a machine model in which the error amount is not zero in any of the direction different from the direction of the motion of the mechanical structure among the axial directions.

A machining program generation device that generates a machining program of a numerical control machine tool, the numerical control machine tool including a drive mechanism provided for each of a plurality of axes, including a mechanical structure to perform motion by power that is transmitted from the drive mechanism, and machining a workpiece using a tool attached to the mechanical structure, the machining program generation device comprising:

• model holding circuitry that holds a machine model, the machine model being a model that simulates deformation of the mechanical structure accompanying the motion of the mechanical structure in axial directions and representing an error amount as an amount of displacement of the tool in the axial directions due to the deformation of the mechanical structure, the axial directions being directions of corresponding ones of the plurality of the axes;
• machining error estimation circuitry to estimate an error direction and the error amount in the error direction on the basis of axis data that is data on drive of the drive mechanism and the machine model, and output machining error information indicating the error direction estimated and the error amount estimated, the error direction being a direction different from a direction of the motion of the mechanical structure among the axial directions and being a direction in which displacement of the tool occurs;
• correction amount arithmetic circuitry to select one or more of the axes subject to correction on the basis of the machining error information, and perform arithmetic to find a correction amount for correcting the motion due to the drive mechanism for the axis selected;
• and
• machining program correction circuitry to correct the machining program in accordance with the correction amount, wherein
• the machine model is a machine model in which the error amount is not zero in any of the direction different from the direction of the motion of the mechanical structure among the axial directions.

A machining program generation method that generates a machining program of a numerical control machine tool, the numerical control machine tool including a drive mechanism provided for each of a plurality of axes, including a mechanical structure to perform motion by power that is transmitted from the drive mechanism, and machining a workpiece using a tool attached to the mechanical structure, the machining program generation method comprising:

• reading a machine model, the machine model being a model that simulates deformation of the mechanical structure accompanying the motion of the mechanical structure in axial directions and representing an error amount as an amount of displacement of the tool in the axial directions due to the deformation of the mechanical structure, the axial directions being directions of corresponding ones of the plurality of the axes;
• estimating an error direction and the error amount in the error direction on the basis of axis data that is data on drive of the drive mechanism and the machine model, and outputting machining error information indicating the error direction estimated and the error amount estimated, the error direction being a direction different from a direction of the motion of the mechanical structure among the axial directions and being a direction in which displacement of the tool occurs;
• selecting one or more of the axes subject to correction on the basis of the machining error information, and performing arithmetic to find a correction amount for correcting the motion due to the drive mechanism for the axis selected;
• and
• correcting the machining program in accordance with the correction amount, wherein
• the machine model is a machine model in which the error amount is not zero in any of the direction different from the direction of the motion of the mechanical structure among the axial directions.