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:
Aug. 19, 2014
Filed:
Aug. 09, 2012
Hung D. VU, Pembroke, MA (US);
Hung D. Vu, Pembroke, MA (US);
Oriental Motor Boston Technology Group Incorporated, Braintree, MA (US);
Abstract
A stepper motor system and apparatus use a position-feedback device, which may have a resolution capability as low as 200 counts per motor shaft revolution, for misstep detection and motor step recovery. In use of the system, position deviation is computed periodically and cyclically, by subtracting the feedback position from the corresponding commanded position, to determine the load angle, implicitly, and the operating status of the motor. If the load angle is within an established allowable range of values, normal stepper operation along the programmed trajectory is maintained, without adjustment. A load angle that exceeds the limits of that range however indicates that a misstep has occurred, and the system controller initiates immediate action to recover lost motor steps, to reestablish synchronism, and to then continue toward the final target position, with minimal loss of time.