Numerical control device

Abstract

This numerical control device (1) for a machine tool, which controls the positional relationship between a workpiece on a table and a tool by moving the table or the tool along a plurality of translation axes, is provided with the following: an analysis processing unit (21) that outputs a movement path and a feed speed along said movement path on the basis of a machining program that contains a plurality of command blocks; a speed-waveform calculation unit (23) that calculates a speed waveform between a stationary state and a state corresponding to the aforementioned feed speed on the basis of said feed speed and preset acceleration and jerk limits; a corner-curve calculation unit (24) that calculates curve equations for corner curves obtained by smoothing the abovementioned movement path at the boundaries between the abovementioned command blocks on the basis of a preset path-error limit, the movement path, and the aforementioned speed waveform; and a movement-command generation unit (22) that outputs a movement command for each translation axis on the basis of the movement path and the aforementioned curve equations.

Description

technical field [0001] The present invention relates to a numerical control device capable of smoothing a moving path in pre-interpolation acceleration and deceleration control. Background technique [0002] In a machine tool equipped with a numerical control device, each drive shaft is controlled so as to move to a position commanded in a machining program, and machining is performed while moving a movable part. In the numerical control device, there is pre-interpolation acceleration and deceleration as a technique for accurately moving at a commanded speed along a movement path written in a machining program. Acceleration and deceleration before interpolation is a technique of generating an acceleration and deceleration waveform in the direction along the movement path, that is, a tangential direction, and performing interpolation while matching the generated acceleration and deceleration waveform to the movement path. In general, when pre-interpolation acceleration and d...

AI Technical Summary

Problems solved by technology

In general, when pre-interpolation acceleration and deceleration is used, excessive acceleration occurs in a path that changes rapidly, such as a corner that is a junction of each movement command. Therefore, there is a problem that each Each corner decelerates until it reaches an appropriate speed, and after passing through a corner, accelerates until it reaches the commanded feed speed, so the moving time becomes longer.

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