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. 06, 1992
Filed:
Mar. 19, 1991
Toshihiro Ueta, Mishima, JP;
Ikuo Kuribayashi, Mishima, JP;
Masayuki Kato, Mishima, JP;
Jun Fujita, Numazu, JP;
Toshiba Kikai Kabushiki Kaisha, Tokyo, JP;
Abstract
In a machine tool having a table adapted to support a workpiece, a plurality of drive shafts for moving the table in three directional directions by servomotors, servo control apparatus controlling the servomotors in response to position instructions, drive shaft control apparatus including position detectors of the servomotors, each drive shaft control apparatus is made up of a servomotor rotation reversal detector for producing a movement reversal signal, a memory device for storing correction amounts necessary to compensate for a position error of the axis of the spindle of the machine tool which occurs as a result of reversal of the direction of movement of the drive shaft and other drive shafts and a transfer switches for selecting the memory device in response to the movement reversal signal and for feeding back to the servo control apparatus the correction amount read out from the memory device.