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. 31, 2000
Filed:
Jan. 13, 1999
Yasuo Yamane, Hiroshima, JP;
Masahiko Fukuta, Numazu, JP;
Takao Date, Tagata-gun, JP;
Satoshi Kumamoto, Mishima, JP;
Toshiba Kikai Kabushiki Kaisha, Tokyo, JP;
Abstract
An electric path (E) is formed by connecting a spindle (11), a tool (12), a table (4), a base (2), a column (5) and a housing (13) including a capacitor (C0) having the spindle (11) and the housing (13) as electrodes, and electric current is sent to the electric path (E) by a current generator (51). An electro-capacitance change is detected by measuring a current value in the electric path (E) by an electro-capacitance detector (52) to detect a state of a bearing gap between the spindle (11) and the housing (13). No multiple sensors are necessary and the spindle state detector (50) can be simplified.