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:
Dec. 17, 2019
Filed:
Jun. 22, 2015
Dmg Mori Co., Ltd., Nara, JP;
Yoichi Okamoto, Nara, JP;
Eiichiro Gomi, Nara, JP;
DMG Mori Co. Ltd., Nara, JP;
Abstract
A machine tool for detecting a brake failure more reliably in a mechanism that stops the rotation of a vertical shaft by at least two brakes includes a ball screw extended in a vertical direction, a driving motor that rotates the ball screw, a movable part that vertically moves along the ball screw in accordance with the rotation of the ball screw driven by the driving motor, at least two brakes that prevent a fall of the movable part while power supply to the driving motor is stopped, a brake controller that releases at least one of the at least two brakes while power supply to the driving motor is stopped, and a detector that detects presence/absence of a fall of the movable part or a fall distance of the movable part resulting from the release of the at least one brake, thereby detecting a trouble of an unreleased one of the at least two brakes.