Controller for machine tool and five-axis simultaneous control machine tool controlled thereby

A five-axis simultaneous control machine tool controlled by a controller for a machine tool, comprising;

• a bed;
• a spindle housing mounted movably on said bed to support a tool;
• a table mounted movably on said bed to support a workpiece;
• said spindle housing and said table are moved relatively along three linear axes and also pivoted relatively along two pivoting axes;
• and
• said controller for said five-axis simultaneous control machine tool controlling a machining position and a machining attitude of said tool relative to said workpiece by driving any of motors for driving axes including said three linear axes and said two pivoting axes based on a control data, comprising;
• a detecting member detecting said machining position where said pivoting axis is reversed in machining by said machine tool based on said control data;
• an allowable position error setting member setting an allowable position error between a commanded machining position and an actual machining position;
• an allowable angular error calculating member calculating an allowable angular error of a difference between a commanded angle of said pivoting axis and an actual angle of said pivoting axis based on said allowable position error and said distance;
• a machine character memorizing member memorizing previously a machine character of said machine tool based on an actual position difference between said commanded machining position and said actual machining position measured in an actual operation of said machine tool;
• an allowable acceleration deciding member deciding said allowable acceleration about said pivoting axis based on said machine character and said allowable position error or based on said machine character and said allowable angular error;
• and
• a controlling member controlling a velocity about said driving axis based on said allowable acceleration.

A five-axis simultaneous control machine tool controlled by a controller for a machine tool, comprising;

• a bed;
• a spindle housing mounted movably on said bed to support a tool;
• a table mounted movably on said bed to support a workpiece;
• said spindle housing and said table are moved relatively along three linear axes and also pivoted relatively along two pivoting axes;
• and
• said controller for said five-axis simultaneous control machine tool controlling a machining position and a machining attitude of said tool relative to said workpiece by driving any of motors for driving axes including said three linear axes and said two pivoting axes based on a control data, comprising;
• a detecting member detecting said machining position where said pivoting axis is reversed in machining by said machine tool based on said control data;
• an allowable position error setting member setting an allowable position error between a commanded machining position and an actual machining position;
• an allowable angular error calculating member calculating an allowable angular error of a difference between a commanded angle of said pivoting axis and an actual angle of said pivoting axis based on said allowable position error and said distance;
• a machine character memorizing member memorizing a machine character corresponding to a machining profile at said machining position of said reversed axis;
• an allowable acceleration deciding member deciding said allowable acceleration about said pivoting axis based on said machine character and said allowable position error or based on said machine character and said allowable angular error;
• and
• a controlling member controlling a velocity about said driving axis based on said allowable acceleration.