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:
Nov. 20, 2001
Filed:
Mar. 01, 1999
Fanuc Ltd., Yamanashi, JP;
Abstract
It is assumed that an element to be detected,in a position sensor is mounted on a rotary shaft with the center O′ of the element to be detected eccentric from a center of rotation O by a distance d. When the rotary shaft is rotated at a fixed speed, the positions at angles 0° and 180° are accurately detected by a sensor,, while the positions at angles 90° and 270°, the sensor detects the positions P,′ and P,′, instead of P,and P,which are originally to be detected, resulting in undulation of detected positions as shown in FIG. 3(,). The peak value of the unduration and an angle of rotation at which the peak value is found are determined. An amount of eccentricity d is found from the peak value, a detection error with respect to the command position (angle) is found from the amount of eccentricity d and the angle at which the peak value is found, and correction the by detection error is made with respect to the command position, providing a corrected command position to a motor.