Control device for controlling a plurality of servo motors and servo motor controlling method

A servo motor controlling method for use in a servo motor control device for controlling a plurality of servo motors, said method comprising:

• outputting a move command signal by a commanding section to drive and control the servo motors;
• performing interpolation based on the move command signal output by said commanding section and outputting an interpolating signal based on the interpolation by an interpolating section, said interpolating section being capable of performing circular arc interpolation when said commanding section outputs a circular arc move command signal;
• outputting distributing pulses by a distributing section into each of the servo motors based on the interpolating signal output by said interpolating section and an acceleration and deceleration time period;
• and
• determining and changing the acceleration and deceleration time period by an acceleration and deceleration time period determining section at least at the start of said circular arc interpolation and at an end of said circular arc interpolation so that upon the start of said circular arc interpolation, a value of said acceleration and deceleration time period is decreased from a predetermined initial value to a predetermined minimal value during said circular arc interpolation, and said value of said acceleration and deceleration time period is returned to said predetermined initial value when said circular arc interpolation is completed and, alternatively, when a command-designated stop occurs during said circular arc interpolation.

A control device for controlling a plurality of servo motors comprising:

• commanding means for outputting a move command signal to drive and control a plurality of servo motors;
• interpolating means for performing interpolation based on the move command signal output by said commanding means, and by decreasing a value of an acceleration and deceleration time period from a predetermined initial value to a predetermined minimal value during a circular arc interpolation, and for outputting an interpolating signal based on the interpolation, said interpolating means being capable of performing circular arc interpolation when said commanding means outputs a circular arc move command signal;
• and
• distributing means for outputting distribution pulse trains into each of the servo motors based on the interpolating signal output by said interpolating means received by said distributing means, wherein said distributing means accumulates distribution pulses during circular arc interpolation, and outputs said accumulated distribution pulses when said circular arc interpolation is completed and, alternatively, when a command-designated stop occurs during said circular arc interpolation.

A servo motor controlling method for use in a servo motor control device for controlling a plurality of servo motors, said method comprising:

• outputting a move command signal by a commanding section to drive and control the servo motors;
• performing interpolation based on the move command signal output by said commanding section and by decreasing a value of an acceleration and deceleration time period from a predetermined initial value to zero during a circular arc interpolation, and outputting an interpolating signal based on the interpolation by an interpolating section, said interpolating section being capable of performing circular arc interpolation when said commanding section outputs a circular arc move command signal;
• outputting distribution pulses by a distributing section into each of the servo motors based on the interpolating signal output by said interpolating section;
• accumulating distribution pulses by said distributing section during circular arc interpolation;
• and
• outputting said accumulated distribution pulses when said circular arc interpolation is completed and, alternatively, when a command-designated stop occurs during said circular arc interpolation, wherein said servo motors are smoothly and gradually stopped when said circular arc interpolation is completed and, alternatively, when said command-designated stop occurs during said circular arc interpolation.