The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 30, 2005
Filed:
Dec. 30, 2003
Sang Ho Lee, Kyongnam, KR;
Sang Ho Lee, Kyongnam, KR;
Daewoo Heavy Industries & Machinery Ltd., Incheon, KR;
Abstract
A method and apparatus is provided of detecting tool abnormality in a machine tool. Permissible minimum and maximum values of load current in a real cutting section are determined for a spindle motor and a servomotor during normal operation of the machine tool. The load current of the spindle motor and the servomotor is measured while the machine tool is operated. The load current measured in a real cutting section other than a non-cutting section is extracted by way of filtering the load current measured. A judgment is made as to whether the extracted load current is within a range between the minimum and maximum values. Occurrence of the tool abnormality is confirmed if the extracted load current falls outside the range. This enables the machine tool to detect not only overload condition due to excessive wear of a tool but also non-load condition induced by a tool breakage.