| 摘要 |
PURPOSE:To enable the proper judgement of a tool service life by concluding that the service life has reached a limit when the frequencies of loading or the counted values of timing have reached a predetermined value on the sensing of a load working on a motor for turning a main spindle or a motor for the feeding thereof. CONSTITUTION:A main spindle load detector 4 senses a load working on a spindle motor 2 due to the cutting of a workpiece 1, and a Z-axis feed load detector 5 senses a load working on a Z-axis feed motor 3 due to the cutting of the workpiece 1. Thereafter, a monitor load selecting device 6 counts or selects one of said loads and the output of the load detector as selected is given to a load counter 8. Then, a tool service life comparator 10 compares a value counted by the load counter 8 with a service life set value determined with a tool service life setter 9. When the counted value has exceeded the set value, the tool service life detector 11 senses that the service life of the tool has reached a limit, and outputs a signal including warning. |
