Method for eliminating follow-up delay in full-close feedback nc system

Abstract

Abstract PURPOSE:To attain control on the table position of a machine tool with high accuracy, by adding a specified quantity of correction and correcting time, when a position error in the moving direction of a servo system arrives at zero, at the time of inverting the moving direction. CONSTITUTION:A curve 11 represents a command value and the table position, and both of them nearly coincide, and the correction of a correction quantity Xc, and a correction time Tc for the command value is performed at the time of inverting the moving direction, as shown in broken line 13. A curve 12 represents the motion of a motor, and it is separated by a quantity of backlash against the curve 11, and the correction quantity Xc is the quantity of Xc=K.DELTAx, and the correction time Tc is the time of Tc=1divided by Pgdivided by K. A position gain Pg is a value in which the speed of a machine in a servo system is divided by a follow-up deviation, and it is generally around 1/30 per sec. As a correction coefficient K, an appropriate value in which the correction time Tc becomes the value of integer times the time divisional cycle (ITP) of a system, is selected. By controlling the operation of the motor rapidly by a command corrected in such way, it is possible to follow up the table position at a requested command value with high accuracy.

Inventors

• 👤 Kanemasa Okuda
• 👤 奥田　兼正

Bibliographic Details