Controller for machine tool
AssigneeFanuc Corporation
InventorYasuaki KOYAMA
Life of this patent
Estimating the term…
Abstract
A thermal displacement state (target thermal displacement state) in which thermal displacement of a machine tool is saturated when the machine tool is operated based on a machining program is previously stored, and a warm-up operation pattern of a motor is determined so as to approach the target thermal displacement state. The motor is driven based on the warm-up operation pattern and the warm-up operation of the motor is stopped if the thermal displacement state of the machine tool is within a predetermined range.
Claims4
A controller for a machine tool, which drives a motor based on a machining program, thereby driving a spindle and a feed screw, the controller comprising:
- a storage unit that stores therein, as a target thermal displacement state, a thermal displacement state in which thermal displacement of the machine tool is saturated when the machine tool is operated in advance based on the machining program;
- a warm-up operation determination unit configured to determine a warm-up operation pattern of the motor so as to approach the target thermal displacement state;
- a thermal displacement state calculation unit configured to calculate the thermal displacement state of the machine tool;
- a motor drive unit configured to drive the motor according to the warm-up operation pattern determined by the warm-up operation determination unit;
- and
- a motor stop unit configured to calculate the thermal displacement state of the machine tool for each predetermined period by means of the thermal displacement state calculation unit, compare the calculated thermal displacement state with the target thermal displacement state, and stop the motor drive unit if the difference between the calculated thermal displacement state and the target thermal displacement state is within a predetermined threshold value.
Dependencies are inferred from the claim text.