Title:
DEVICE AND METHOD FOR DETECTING ABNORMALITY IN CUTTING TOOL
Document Type and Number:
WIPO Patent Application WO/2020/138025
Kind Code:
A1
Abstract:
Provided are an abnormality detection device and method with which it is possible to detect breakage in a blade edge and suppress extension of tool damage in an automatic production line. This abnormality detection method or device for detecting breakage in a cutting tool that comprises a plurality of blades includes: (A) receiving a measurement signal, which is a result of measurement of a current value or a voltage value of a main-shaft motor that induces rotation of a main shaft of a machine tool in which the cutting tool is installed; (B) performing a filter process on the measurement signal and storing the filtered measurement signal in time series in a storage unit; (C) performing abnormality detection; and (D) when it is assessed in the abnormality detection in (C) that that tool breakage has occurred, outputting to the machine tool a machining control command designated by a control parameter. The (C) performance of the abnormality detection includes: (C1) extracting, from the stored measurement signal, a frequency analysis data number measurement signal in a machining region for which it is predicted that the number of blades operating simultaneously is one, and calculating a frequency spectrum; and (C2) assessing that tool breakage has occurred on the basis of the amplitude of an assessment frequency (= rotational frequency × n, where 1 ≤ n < number of tool blades, and n is an integer) designated by the control parameter in the frequency spectrum, and also on the basis of a threshold value designated by the control parameter.
Inventors:
FUKUOKA NOBUHIKO (JP)
KOMIYA SEIJI (JP)
MATSUZAKI YUI (JP)
OHASHI HARUKI (JP)
KOMIYA SEIJI (JP)
MATSUZAKI YUI (JP)
OHASHI HARUKI (JP)
Application Number:
PCT/JP2019/050486
Publication Date:
July 02, 2020
Filing Date:
December 24, 2019
Export Citation:
Assignee:
HITACHI METALS LTD (JP)
International Classes:
B23Q17/09
Foreign References:
| JPH09174383A | 1997-07-08 | |||
| JPS62193749A | 1987-08-25 | |||
| JPS59175941A | 1984-10-05 | |||
| JPS59175945A | 1984-10-05 | |||
| JP2010069540A | 2010-04-02 |
Attorney, Agent or Firm:
SEIRYO I.P.C. (JP)
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