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:
Oct. 08, 1996
Filed:
Oct. 14, 1994
Applicant:
Inventors:
Hirochika Ueyama, Hirakata, JP;
Yasuhiro Yukitake, Kashiwara, JP;
Assignee:
Koyo Seiko Co., Ltd., Osaka, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B24B / ;
U.S. Cl.
CPC ...
451 11 ; 310 905 ;
Abstract
A machine tool comprises a spindle device carrying a tool element attached to the forward end of a rotor spindle drivingly rotatable as supported by a control-type magnetic bearing device, a working force calculating unit for calculating a working force acting on the tool element upon the tool element coming into contact with a workpiece based on exciting current of a magnetic bearing of the bearing device, and a discriminating unit for discerning whether the contact of the tool element with the workpiece is normal or abnormal based on variations in the working force.